fs/xfs/libxfs/xfs_bmap.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (c) 2000-2006 Silicon Graphics, Inc.
   4  * All Rights Reserved.
   5  */
   6 #include "xfs.h"
   7 #include "xfs_fs.h"
   8 #include "xfs_shared.h"
   9 #include "xfs_format.h"
  10 #include "xfs_log_format.h"
  11 #include "xfs_trans_resv.h"
  12 #include "xfs_bit.h"
  13 #include "xfs_sb.h"
  14 #include "xfs_mount.h"
  15 #include "xfs_defer.h"
  16 #include "xfs_dir2.h"
  17 #include "xfs_inode.h"
  18 #include "xfs_btree.h"
  19 #include "xfs_trans.h"
  20 #include "xfs_alloc.h"
  21 #include "xfs_bmap.h"
  22 #include "xfs_bmap_util.h"
  23 #include "xfs_bmap_btree.h"
  24 #include "xfs_rtalloc.h"
  25 #include "xfs_errortag.h"
  26 #include "xfs_error.h"
  27 #include "xfs_quota.h"
  28 #include "xfs_trans_space.h"
  29 #include "xfs_buf_item.h"
  30 #include "xfs_trace.h"
  31 #include "xfs_attr_leaf.h"
  32 #include "xfs_filestream.h"
  33 #include "xfs_rmap.h"
  34 #include "xfs_ag.h"
  35 #include "xfs_ag_resv.h"
  36 #include "xfs_refcount.h"
  37 #include "xfs_icache.h"
  38 #include "xfs_iomap.h"
  39
  40 struct kmem_cache               *xfs_bmap_intent_cache;
  41
  42 /*
  43  * Miscellaneous helper functions
  44  */
  45
  46 /*
  47  * Compute and fill in the value of the maximum depth of a bmap btree
  48  * in this filesystem.  Done once, during mount.
  49  */
  50 void
  51 xfs_bmap_compute_maxlevels(
  52         xfs_mount_t     *mp,            /* file system mount structure */
  53         int             whichfork)      /* data or attr fork */
  54 {
  55         uint64_t        maxblocks;      /* max blocks at this level */
  56         xfs_extnum_t    maxleafents;    /* max leaf entries possible */
  57         int             level;          /* btree level */
  58         int             maxrootrecs;    /* max records in root block */
  59         int             minleafrecs;    /* min records in leaf block */
  60         int             minnoderecs;    /* min records in node block */
  61         int             sz;             /* root block size */
  62
  63         /*
  64          * The maximum number of extents in a fork, hence the maximum number of
  65          * leaf entries, is controlled by the size of the on-disk extent count.
  66          *
  67          * Note that we can no longer assume that if we are in ATTR1 that the
  68          * fork offset of all the inodes will be
  69          * (xfs_default_attroffset(ip) >> 3) because we could have mounted with
  70          * ATTR2 and then mounted back with ATTR1, keeping the i_forkoff's fixed
  71          * but probably at various positions. Therefore, for both ATTR1 and
  72          * ATTR2 we have to assume the worst case scenario of a minimum size
  73          * available.
  74          */
  75         maxleafents = xfs_iext_max_nextents(xfs_has_large_extent_counts(mp),
  76                                 whichfork);
  77         if (whichfork == XFS_DATA_FORK)
  78                 sz = XFS_BMDR_SPACE_CALC(MINDBTPTRS);
  79         else
  80                 sz = XFS_BMDR_SPACE_CALC(MINABTPTRS);
  81
  82         maxrootrecs = xfs_bmdr_maxrecs(sz, 0);
  83         minleafrecs = mp->m_bmap_dmnr[0];
  84         minnoderecs = mp->m_bmap_dmnr[1];
  85         maxblocks = howmany_64(maxleafents, minleafrecs);
  86         for (level = 1; maxblocks > 1; level++) {
  87                 if (maxblocks <= maxrootrecs)
  88                         maxblocks = 1;
  89                 else
  90                         maxblocks = howmany_64(maxblocks, minnoderecs);
  91         }
  92         mp->m_bm_maxlevels[whichfork] = level;
  93         ASSERT(mp->m_bm_maxlevels[whichfork] <= xfs_bmbt_maxlevels_ondisk());
  94 }
  95
  96 unsigned int
  97 xfs_bmap_compute_attr_offset(
  98         struct xfs_mount        *mp)
  99 {
 100         if (mp->m_sb.sb_inodesize == 256)
 101                 return XFS_LITINO(mp) - XFS_BMDR_SPACE_CALC(MINABTPTRS);
 102         return XFS_BMDR_SPACE_CALC(6 * MINABTPTRS);
 103 }
 104
 105 STATIC int                              /* error */
 106 xfs_bmbt_lookup_eq(
 107         struct xfs_btree_cur    *cur,
 108         struct xfs_bmbt_irec    *irec,
 109         int                     *stat)  /* success/failure */
 110 {
 111         cur->bc_rec.b = *irec;
 112         return xfs_btree_lookup(cur, XFS_LOOKUP_EQ, stat);
 113 }
 114
 115 STATIC int                              /* error */
 116 xfs_bmbt_lookup_first(
 117         struct xfs_btree_cur    *cur,
 118         int                     *stat)  /* success/failure */
 119 {
 120         cur->bc_rec.b.br_startoff = 0;
 121         cur->bc_rec.b.br_startblock = 0;
 122         cur->bc_rec.b.br_blockcount = 0;
 123         return xfs_btree_lookup(cur, XFS_LOOKUP_GE, stat);
 124 }
 125
 126 /*
 127  * Check if the inode needs to be converted to btree format.
 128  */
 129 static inline bool xfs_bmap_needs_btree(struct xfs_inode *ip, int whichfork)
 130 {
 131         struct xfs_ifork *ifp = xfs_ifork_ptr(ip, whichfork);
 132
 133         return whichfork != XFS_COW_FORK &&
 134                 ifp->if_format == XFS_DINODE_FMT_EXTENTS &&
 135                 ifp->if_nextents > XFS_IFORK_MAXEXT(ip, whichfork);
 136 }
 137
 138 /*
 139  * Check if the inode should be converted to extent format.
 140  */
 141 static inline bool xfs_bmap_wants_extents(struct xfs_inode *ip, int whichfork)
 142 {
 143         struct xfs_ifork *ifp = xfs_ifork_ptr(ip, whichfork);
 144
 145         return whichfork != XFS_COW_FORK &&
 146                 ifp->if_format == XFS_DINODE_FMT_BTREE &&
 147                 ifp->if_nextents <= XFS_IFORK_MAXEXT(ip, whichfork);
 148 }
 149
 150 /*
 151  * Update the record referred to by cur to the value given by irec
 152  * This either works (return 0) or gets an EFSCORRUPTED error.
 153  */
 154 STATIC int
 155 xfs_bmbt_update(
 156         struct xfs_btree_cur    *cur,
 157         struct xfs_bmbt_irec    *irec)
 158 {
 159         union xfs_btree_rec     rec;
 160
 161         xfs_bmbt_disk_set_all(&rec.bmbt, irec);
 162         return xfs_btree_update(cur, &rec);
 163 }
 164
 165 /*
 166  * Compute the worst-case number of indirect blocks that will be used
 167  * for ip's delayed extent of length "len".
 168  */
 169 STATIC xfs_filblks_t
 170 xfs_bmap_worst_indlen(
 171         xfs_inode_t     *ip,            /* incore inode pointer */
 172         xfs_filblks_t   len)            /* delayed extent length */
 173 {
 174         int             level;          /* btree level number */
 175         int             maxrecs;        /* maximum record count at this level */
 176         xfs_mount_t     *mp;            /* mount structure */
 177         xfs_filblks_t   rval;           /* return value */
 178
 179         mp = ip->i_mount;
 180         maxrecs = mp->m_bmap_dmxr[0];
 181         for (level = 0, rval = 0;
 182              level < XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK);
 183              level++) {
 184                 len += maxrecs - 1;
 185                 do_div(len, maxrecs);
 186                 rval += len;
 187                 if (len == 1)
 188                         return rval + XFS_BM_MAXLEVELS(mp, XFS_DATA_FORK) -
 189                                 level - 1;
 190                 if (level == 0)
 191                         maxrecs = mp->m_bmap_dmxr[1];
 192         }
 193         return rval;
 194 }
 195
 196 /*
 197  * Calculate the default attribute fork offset for newly created inodes.
 198  */
 199 uint
 200 xfs_default_attroffset(
 201         struct xfs_inode        *ip)
 202 {
 203         if (ip->i_df.if_format == XFS_DINODE_FMT_DEV)
 204                 return roundup(sizeof(xfs_dev_t), 8);
 205         return M_IGEO(ip->i_mount)->attr_fork_offset;
 206 }
 207
 208 /*
 209  * Helper routine to reset inode i_forkoff field when switching attribute fork
 210  * from local to extent format - we reset it where possible to make space
 211  * available for inline data fork extents.
 212  */
 213 STATIC void
 214 xfs_bmap_forkoff_reset(
 215         xfs_inode_t     *ip,
 216         int             whichfork)
 217 {
 218         if (whichfork == XFS_ATTR_FORK &&
 219             ip->i_df.if_format != XFS_DINODE_FMT_DEV &&
 220             ip->i_df.if_format != XFS_DINODE_FMT_BTREE) {
 221                 uint    dfl_forkoff = xfs_default_attroffset(ip) >> 3;
 222
 223                 if (dfl_forkoff > ip->i_forkoff)
 224                         ip->i_forkoff = dfl_forkoff;
 225         }
 226 }
 227
 228 #ifdef DEBUG
 229 STATIC struct xfs_buf *
 230 xfs_bmap_get_bp(
 231         struct xfs_btree_cur    *cur,
 232         xfs_fsblock_t           bno)
 233 {
 234         struct xfs_log_item     *lip;
 235         int                     i;
 236
 237         if (!cur)
 238                 return NULL;
 239
 240         for (i = 0; i < cur->bc_maxlevels; i++) {
 241                 if (!cur->bc_levels[i].bp)
 242                         break;
 243                 if (xfs_buf_daddr(cur->bc_levels[i].bp) == bno)
 244                         return cur->bc_levels[i].bp;
 245         }
 246
 247         /* Chase down all the log items to see if the bp is there */
 248         list_for_each_entry(lip, &cur->bc_tp->t_items, li_trans) {
 249                 struct xfs_buf_log_item *bip = (struct xfs_buf_log_item *)lip;
 250
 251                 if (bip->bli_item.li_type == XFS_LI_BUF &&
 252                     xfs_buf_daddr(bip->bli_buf) == bno)
 253                         return bip->bli_buf;
 254         }
 255
 256         return NULL;
 257 }
 258
 259 STATIC void
 260 xfs_check_block(
 261         struct xfs_btree_block  *block,
 262         xfs_mount_t             *mp,
 263         int                     root,
 264         short                   sz)
 265 {
 266         int                     i, j, dmxr;
 267         __be64                  *pp, *thispa;   /* pointer to block address */
 268         xfs_bmbt_key_t          *prevp, *keyp;
 269
 270         ASSERT(be16_to_cpu(block->bb_level) > 0);
 271
 272         prevp = NULL;
 273         for( i = 1; i <= xfs_btree_get_numrecs(block); i++) {
 274                 dmxr = mp->m_bmap_dmxr[0];
 275                 keyp = XFS_BMBT_KEY_ADDR(mp, block, i);
 276
 277                 if (prevp) {
 278                         ASSERT(be64_to_cpu(prevp->br_startoff) <
 279                                be64_to_cpu(keyp->br_startoff));
 280                 }
 281                 prevp = keyp;
 282
 283                 /*
 284                  * Compare the block numbers to see if there are dups.
 285                  */
 286                 if (root)
 287                         pp = XFS_BMAP_BROOT_PTR_ADDR(mp, block, i, sz);
 288                 else
 289                         pp = XFS_BMBT_PTR_ADDR(mp, block, i, dmxr);
 290
 291                 for (j = i+1; j <= be16_to_cpu(block->bb_numrecs); j++) {
 292                         if (root)
 293                                 thispa = XFS_BMAP_BROOT_PTR_ADDR(mp, block, j, sz);
 294                         else
 295                                 thispa = XFS_BMBT_PTR_ADDR(mp, block, j, dmxr);
 296                         if (*thispa == *pp) {
 297                                 xfs_warn(mp, "%s: thispa(%d) == pp(%d) %lld",
 298                                         __func__, j, i,
 299                                         (unsigned long long)be64_to_cpu(*thispa));
 300                                 xfs_err(mp, "%s: ptrs are equal in node\n",
 301                                         __func__);
 302                                 xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
 303                         }
 304                 }
 305         }
 306 }
 307
 308 /*
 309  * Check that the extents for the inode ip are in the right order in all
 310  * btree leaves. THis becomes prohibitively expensive for large extent count
 311  * files, so don't bother with inodes that have more than 10,000 extents in
 312  * them. The btree record ordering checks will still be done, so for such large
 313  * bmapbt constructs that is going to catch most corruptions.
 314  */
 315 STATIC void
 316 xfs_bmap_check_leaf_extents(
 317         struct xfs_btree_cur    *cur,   /* btree cursor or null */
 318         xfs_inode_t             *ip,            /* incore inode pointer */
 319         int                     whichfork)      /* data or attr fork */
 320 {
 321         struct xfs_mount        *mp = ip->i_mount;
 322         struct xfs_ifork        *ifp = xfs_ifork_ptr(ip, whichfork);
 323         struct xfs_btree_block  *block; /* current btree block */
 324         xfs_fsblock_t           bno;    /* block # of "block" */
 325         struct xfs_buf          *bp;    /* buffer for "block" */
 326         int                     error;  /* error return value */
 327         xfs_extnum_t            i=0, j; /* index into the extents list */
 328         int                     level;  /* btree level, for checking */
 329         __be64                  *pp;    /* pointer to block address */
 330         xfs_bmbt_rec_t          *ep;    /* pointer to current extent */
 331         xfs_bmbt_rec_t          last = {0, 0}; /* last extent in prev block */
 332         xfs_bmbt_rec_t          *nextp; /* pointer to next extent */
 333         int                     bp_release = 0;
 334
 335         if (ifp->if_format != XFS_DINODE_FMT_BTREE)
 336                 return;
 337
 338         /* skip large extent count inodes */
 339         if (ip->i_df.if_nextents > 10000)
 340                 return;
 341
 342         bno = NULLFSBLOCK;
 343         block = ifp->if_broot;
 344         /*
 345          * Root level must use BMAP_BROOT_PTR_ADDR macro to get ptr out.
 346          */
 347         level = be16_to_cpu(block->bb_level);
 348         ASSERT(level > 0);
 349         xfs_check_block(block, mp, 1, ifp->if_broot_bytes);
 350         pp = XFS_BMAP_BROOT_PTR_ADDR(mp, block, 1, ifp->if_broot_bytes);
 351         bno = be64_to_cpu(*pp);
 352
 353         ASSERT(bno != NULLFSBLOCK);
 354         ASSERT(XFS_FSB_TO_AGNO(mp, bno) < mp->m_sb.sb_agcount);
 355         ASSERT(XFS_FSB_TO_AGBNO(mp, bno) < mp->m_sb.sb_agblocks);
 356
 357         /*
 358          * Go down the tree until leaf level is reached, following the first
 359          * pointer (leftmost) at each level.
 360          */
 361         while (level-- > 0) {
 362                 /* See if buf is in cur first */
 363                 bp_release = 0;
 364                 bp = xfs_bmap_get_bp(cur, XFS_FSB_TO_DADDR(mp, bno));
 365                 if (!bp) {
 366                         bp_release = 1;
 367                         error = xfs_btree_read_bufl(mp, NULL, bno, &bp,
 368                                                 XFS_BMAP_BTREE_REF,
 369                                                 &xfs_bmbt_buf_ops);
 370                         if (error)
 371                                 goto error_norelse;
 372                 }
 373                 block = XFS_BUF_TO_BLOCK(bp);
 374                 if (level == 0)
 375                         break;
 376
 377                 /*
 378                  * Check this block for basic sanity (increasing keys and
 379                  * no duplicate blocks).
 380                  */
 381
 382                 xfs_check_block(block, mp, 0, 0);
 383                 pp = XFS_BMBT_PTR_ADDR(mp, block, 1, mp->m_bmap_dmxr[1]);
 384                 bno = be64_to_cpu(*pp);
 385                 if (XFS_IS_CORRUPT(mp, !xfs_verify_fsbno(mp, bno))) {
 386                         error = -EFSCORRUPTED;
 387                         goto error0;
 388                 }
 389                 if (bp_release) {
 390                         bp_release = 0;
 391                         xfs_trans_brelse(NULL, bp);
 392                 }
 393         }
 394
 395         /*
 396          * Here with bp and block set to the leftmost leaf node in the tree.
 397          */
 398         i = 0;
 399
 400         /*
 401          * Loop over all leaf nodes checking that all extents are in the right order.
 402          */
 403         for (;;) {
 404                 xfs_fsblock_t   nextbno;
 405                 xfs_extnum_t    num_recs;
 406
 407
 408                 num_recs = xfs_btree_get_numrecs(block);
 409
 410                 /*
 411                  * Read-ahead the next leaf block, if any.
 412                  */
 413
 414                 nextbno = be64_to_cpu(block->bb_u.l.bb_rightsib);
 415
 416                 /*
 417                  * Check all the extents to make sure they are OK.
 418                  * If we had a previous block, the last entry should
 419                  * conform with the first entry in this one.
 420                  */
 421
 422                 ep = XFS_BMBT_REC_ADDR(mp, block, 1);
 423                 if (i) {
 424                         ASSERT(xfs_bmbt_disk_get_startoff(&last) +
 425                                xfs_bmbt_disk_get_blockcount(&last) <=
 426                                xfs_bmbt_disk_get_startoff(ep));
 427                 }
 428                 for (j = 1; j < num_recs; j++) {
 429                         nextp = XFS_BMBT_REC_ADDR(mp, block, j + 1);
 430                         ASSERT(xfs_bmbt_disk_get_startoff(ep) +
 431                                xfs_bmbt_disk_get_blockcount(ep) <=
 432                                xfs_bmbt_disk_get_startoff(nextp));
 433                         ep = nextp;
 434                 }
 435
 436                 last = *ep;
 437                 i += num_recs;
 438                 if (bp_release) {
 439                         bp_release = 0;
 440                         xfs_trans_brelse(NULL, bp);
 441                 }
 442                 bno = nextbno;
 443                 /*
 444                  * If we've reached the end, stop.
 445                  */
 446                 if (bno == NULLFSBLOCK)
 447                         break;
 448
 449                 bp_release = 0;
 450                 bp = xfs_bmap_get_bp(cur, XFS_FSB_TO_DADDR(mp, bno));
 451                 if (!bp) {
 452                         bp_release = 1;
 453                         error = xfs_btree_read_bufl(mp, NULL, bno, &bp,
 454                                                 XFS_BMAP_BTREE_REF,
 455                                                 &xfs_bmbt_buf_ops);
 456                         if (error)
 457                                 goto error_norelse;
 458                 }
 459                 block = XFS_BUF_TO_BLOCK(bp);
 460         }
 461
 462         return;
 463
 464 error0:
 465         xfs_warn(mp, "%s: at error0", __func__);
 466         if (bp_release)
 467                 xfs_trans_brelse(NULL, bp);
 468 error_norelse:
 469         xfs_warn(mp, "%s: BAD after btree leaves for %llu extents",
 470                 __func__, i);
 471         xfs_err(mp, "%s: CORRUPTED BTREE OR SOMETHING", __func__);
 472         xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
 473         return;
 474 }
 475
 476 /*
 477  * Validate that the bmbt_irecs being returned from bmapi are valid
 478  * given the caller's original parameters.  Specifically check the
 479  * ranges of the returned irecs to ensure that they only extend beyond
 480  * the given parameters if the XFS_BMAPI_ENTIRE flag was set.
 481  */
 482 STATIC void
 483 xfs_bmap_validate_ret(
 484         xfs_fileoff_t           bno,
 485         xfs_filblks_t           len,
 486         uint32_t                flags,
 487         xfs_bmbt_irec_t         *mval,
 488         int                     nmap,
 489         int                     ret_nmap)
 490 {
 491         int                     i;              /* index to map values */
 492
 493         ASSERT(ret_nmap <= nmap);
 494
 495         for (i = 0; i < ret_nmap; i++) {
 496                 ASSERT(mval[i].br_blockcount > 0);
 497                 if (!(flags & XFS_BMAPI_ENTIRE)) {
 498                         ASSERT(mval[i].br_startoff >= bno);
 499                         ASSERT(mval[i].br_blockcount <= len);
 500                         ASSERT(mval[i].br_startoff + mval[i].br_blockcount <=
 501                                bno + len);
 502                 } else {
 503                         ASSERT(mval[i].br_startoff < bno + len);
 504                         ASSERT(mval[i].br_startoff + mval[i].br_blockcount >
 505                                bno);
 506                 }
 507                 ASSERT(i == 0 ||
 508                        mval[i - 1].br_startoff + mval[i - 1].br_blockcount ==
 509                        mval[i].br_startoff);
 510                 ASSERT(mval[i].br_startblock != DELAYSTARTBLOCK &&
 511                        mval[i].br_startblock != HOLESTARTBLOCK);
 512                 ASSERT(mval[i].br_state == XFS_EXT_NORM ||
 513                        mval[i].br_state == XFS_EXT_UNWRITTEN);
 514         }
 515 }
 516
 517 #else
 518 #define xfs_bmap_check_leaf_extents(cur, ip, whichfork)         do { } while (0)
 519 #define xfs_bmap_validate_ret(bno,len,flags,mval,onmap,nmap)    do { } while (0)
 520 #endif /* DEBUG */
 521
 522 /*
 523  * Inode fork format manipulation functions
 524  */
 525
 526 /*
 527  * Convert the inode format to extent format if it currently is in btree format,
 528  * but the extent list is small enough that it fits into the extent format.
 529  *
 530  * Since the extents are already in-core, all we have to do is give up the space
 531  * for the btree root and pitch the leaf block.
 532  */
 533 STATIC int                              /* error */
 534 xfs_bmap_btree_to_extents(
 535         struct xfs_trans        *tp,    /* transaction pointer */
 536         struct xfs_inode        *ip,    /* incore inode pointer */
 537         struct xfs_btree_cur    *cur,   /* btree cursor */
 538         int                     *logflagsp, /* inode logging flags */
 539         int                     whichfork)  /* data or attr fork */
 540 {
 541         struct xfs_ifork        *ifp = xfs_ifork_ptr(ip, whichfork);
 542         struct xfs_mount        *mp = ip->i_mount;
 543         struct xfs_btree_block  *rblock = ifp->if_broot;
 544         struct xfs_btree_block  *cblock;/* child btree block */
 545         xfs_fsblock_t           cbno;   /* child block number */
 546         struct xfs_buf          *cbp;   /* child block's buffer */
 547         int                     error;  /* error return value */
 548         __be64                  *pp;    /* ptr to block address */
 549         struct xfs_owner_info   oinfo;
 550
 551         /* check if we actually need the extent format first: */
 552         if (!xfs_bmap_wants_extents(ip, whichfork))
 553                 return 0;
 554
 555         ASSERT(cur);
 556         ASSERT(whichfork != XFS_COW_FORK);
 557         ASSERT(ifp->if_format == XFS_DINODE_FMT_BTREE);
 558         ASSERT(be16_to_cpu(rblock->bb_level) == 1);
 559         ASSERT(be16_to_cpu(rblock->bb_numrecs) == 1);
 560         ASSERT(xfs_bmbt_maxrecs(mp, ifp->if_broot_bytes, 0) == 1);
 561
 562         pp = XFS_BMAP_BROOT_PTR_ADDR(mp, rblock, 1, ifp->if_broot_bytes);
 563         cbno = be64_to_cpu(*pp);
 564 #ifdef DEBUG
 565         if (XFS_IS_CORRUPT(cur->bc_mp, !xfs_btree_check_lptr(cur, cbno, 1)))
 566                 return -EFSCORRUPTED;
 567 #endif
 568         error = xfs_btree_read_bufl(mp, tp, cbno, &cbp, XFS_BMAP_BTREE_REF,
 569                                 &xfs_bmbt_buf_ops);
 570         if (error)
 571                 return error;
 572         cblock = XFS_BUF_TO_BLOCK(cbp);
 573         if ((error = xfs_btree_check_block(cur, cblock, 0, cbp)))
 574                 return error;
 575
 576         xfs_rmap_ino_bmbt_owner(&oinfo, ip->i_ino, whichfork);
 577         error = xfs_free_extent_later(cur->bc_tp, cbno, 1, &oinfo,
 578                         XFS_AG_RESV_NONE);
 579         if (error)
 580                 return error;
 581
 582         ip->i_nblocks--;
 583         xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_BCOUNT, -1L);
 584         xfs_trans_binval(tp, cbp);
 585         if (cur->bc_levels[0].bp == cbp)
 586                 cur->bc_levels[0].bp = NULL;
 587         xfs_iroot_realloc(ip, -1, whichfork);
 588         ASSERT(ifp->if_broot == NULL);
 589         ifp->if_format = XFS_DINODE_FMT_EXTENTS;
 590         *logflagsp |= XFS_ILOG_CORE | xfs_ilog_fext(whichfork);
 591         return 0;
 592 }
 593
 594 /*
 595  * Convert an extents-format file into a btree-format file.
 596  * The new file will have a root block (in the inode) and a single child block.
 597  */
 598 STATIC int                                      /* error */
 599 xfs_bmap_extents_to_btree(
 600         struct xfs_trans        *tp,            /* transaction pointer */
 601         struct xfs_inode        *ip,            /* incore inode pointer */
 602         struct xfs_btree_cur    **curp,         /* cursor returned to caller */
 603         int                     wasdel,         /* converting a delayed alloc */
 604         int                     *logflagsp,     /* inode logging flags */
 605         int                     whichfork)      /* data or attr fork */
 606 {
 607         struct xfs_btree_block  *ablock;        /* allocated (child) bt block */
 608         struct xfs_buf          *abp;           /* buffer for ablock */
 609         struct xfs_alloc_arg    args;           /* allocation arguments */
 610         struct xfs_bmbt_rec     *arp;           /* child record pointer */
 611         struct xfs_btree_block  *block;         /* btree root block */
 612         struct xfs_btree_cur    *cur;           /* bmap btree cursor */
 613         int                     error;          /* error return value */
 614         struct xfs_ifork        *ifp;           /* inode fork pointer */
 615         struct xfs_bmbt_key     *kp;            /* root block key pointer */
 616         struct xfs_mount        *mp;            /* mount structure */
 617         xfs_bmbt_ptr_t          *pp;            /* root block address pointer */
 618         struct xfs_iext_cursor  icur;
 619         struct xfs_bmbt_irec    rec;
 620         xfs_extnum_t            cnt = 0;
 621
 622         mp = ip->i_mount;
 623         ASSERT(whichfork != XFS_COW_FORK);
 624         ifp = xfs_ifork_ptr(ip, whichfork);
 625         ASSERT(ifp->if_format == XFS_DINODE_FMT_EXTENTS);
 626
 627         /*
 628          * Make space in the inode incore. This needs to be undone if we fail
 629          * to expand the root.
 630          */
 631         xfs_iroot_realloc(ip, 1, whichfork);
 632
 633         /*
 634          * Fill in the root.
 635          */
 636         block = ifp->if_broot;
 637         xfs_btree_init_block_int(mp, block, XFS_BUF_DADDR_NULL,
 638                                  XFS_BTNUM_BMAP, 1, 1, ip->i_ino,
 639                                  XFS_BTREE_LONG_PTRS);
 640         /*
 641          * Need a cursor.  Can't allocate until bb_level is filled in.
 642          */
 643         cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork);
 644         cur->bc_ino.flags = wasdel ? XFS_BTCUR_BMBT_WASDEL : 0;
 645         /*
 646          * Convert to a btree with two levels, one record in root.
 647          */
 648         ifp->if_format = XFS_DINODE_FMT_BTREE;
 649         memset(&args, 0, sizeof(args));
 650         args.tp = tp;
 651         args.mp = mp;
 652         xfs_rmap_ino_bmbt_owner(&args.oinfo, ip->i_ino, whichfork);
 653
 654         args.minlen = args.maxlen = args.prod = 1;
 655         args.wasdel = wasdel;
 656         *logflagsp = 0;
 657         error = xfs_alloc_vextent_start_ag(&args,
 658                                 XFS_INO_TO_FSB(mp, ip->i_ino));
 659         if (error)
 660                 goto out_root_realloc;
 661
 662         /*
 663          * Allocation can't fail, the space was reserved.
 664          */
 665         if (WARN_ON_ONCE(args.fsbno == NULLFSBLOCK)) {
 666                 error = -ENOSPC;
 667                 goto out_root_realloc;
 668         }
 669
 670         cur->bc_ino.allocated++;
 671         ip->i_nblocks++;
 672         xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_BCOUNT, 1L);
 673         error = xfs_trans_get_buf(tp, mp->m_ddev_targp,
 674                         XFS_FSB_TO_DADDR(mp, args.fsbno),
 675                         mp->m_bsize, 0, &abp);
 676         if (error)
 677                 goto out_unreserve_dquot;
 678
 679         /*
 680          * Fill in the child block.
 681          */
 682         abp->b_ops = &xfs_bmbt_buf_ops;
 683         ablock = XFS_BUF_TO_BLOCK(abp);
 684         xfs_btree_init_block_int(mp, ablock, xfs_buf_daddr(abp),
 685                                 XFS_BTNUM_BMAP, 0, 0, ip->i_ino,
 686                                 XFS_BTREE_LONG_PTRS);
 687
 688         for_each_xfs_iext(ifp, &icur, &rec) {
 689                 if (isnullstartblock(rec.br_startblock))
 690                         continue;
 691                 arp = XFS_BMBT_REC_ADDR(mp, ablock, 1 + cnt);
 692                 xfs_bmbt_disk_set_all(arp, &rec);
 693                 cnt++;
 694         }
 695         ASSERT(cnt == ifp->if_nextents);
 696         xfs_btree_set_numrecs(ablock, cnt);
 697
 698         /*
 699          * Fill in the root key and pointer.
 700          */
 701         kp = XFS_BMBT_KEY_ADDR(mp, block, 1);
 702         arp = XFS_BMBT_REC_ADDR(mp, ablock, 1);
 703         kp->br_startoff = cpu_to_be64(xfs_bmbt_disk_get_startoff(arp));
 704         pp = XFS_BMBT_PTR_ADDR(mp, block, 1, xfs_bmbt_get_maxrecs(cur,
 705                                                 be16_to_cpu(block->bb_level)));
 706         *pp = cpu_to_be64(args.fsbno);
 707
 708         /*
 709          * Do all this logging at the end so that
 710          * the root is at the right level.
 711          */
 712         xfs_btree_log_block(cur, abp, XFS_BB_ALL_BITS);
 713         xfs_btree_log_recs(cur, abp, 1, be16_to_cpu(ablock->bb_numrecs));
 714         ASSERT(*curp == NULL);
 715         *curp = cur;
 716         *logflagsp = XFS_ILOG_CORE | xfs_ilog_fbroot(whichfork);
 717         return 0;
 718
 719 out_unreserve_dquot:
 720         xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_BCOUNT, -1L);
 721 out_root_realloc:
 722         xfs_iroot_realloc(ip, -1, whichfork);
 723         ifp->if_format = XFS_DINODE_FMT_EXTENTS;
 724         ASSERT(ifp->if_broot == NULL);
 725         xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
 726
 727         return error;
 728 }
 729
 730 /*
 731  * Convert a local file to an extents file.
 732  * This code is out of bounds for data forks of regular files,
 733  * since the file data needs to get logged so things will stay consistent.
 734  * (The bmap-level manipulations are ok, though).
 735  */
 736 void
 737 xfs_bmap_local_to_extents_empty(
 738         struct xfs_trans        *tp,
 739         struct xfs_inode        *ip,
 740         int                     whichfork)
 741 {
 742         struct xfs_ifork        *ifp = xfs_ifork_ptr(ip, whichfork);
 743
 744         ASSERT(whichfork != XFS_COW_FORK);
 745         ASSERT(ifp->if_format == XFS_DINODE_FMT_LOCAL);
 746         ASSERT(ifp->if_bytes == 0);
 747         ASSERT(ifp->if_nextents == 0);
 748
 749         xfs_bmap_forkoff_reset(ip, whichfork);
 750         ifp->if_u1.if_root = NULL;
 751         ifp->if_height = 0;
 752         ifp->if_format = XFS_DINODE_FMT_EXTENTS;
 753         xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
 754 }
 755
 756
 757 STATIC int                              /* error */
 758 xfs_bmap_local_to_extents(
 759         xfs_trans_t     *tp,            /* transaction pointer */
 760         xfs_inode_t     *ip,            /* incore inode pointer */
 761         xfs_extlen_t    total,          /* total blocks needed by transaction */
 762         int             *logflagsp,     /* inode logging flags */
 763         int             whichfork,
 764         void            (*init_fn)(struct xfs_trans *tp,
 765                                    struct xfs_buf *bp,
 766                                    struct xfs_inode *ip,
 767                                    struct xfs_ifork *ifp))
 768 {
 769         int             error = 0;
 770         int             flags;          /* logging flags returned */
 771         struct xfs_ifork *ifp;          /* inode fork pointer */
 772         xfs_alloc_arg_t args;           /* allocation arguments */
 773         struct xfs_buf  *bp;            /* buffer for extent block */
 774         struct xfs_bmbt_irec rec;
 775         struct xfs_iext_cursor icur;
 776
 777         /*
 778          * We don't want to deal with the case of keeping inode data inline yet.
 779          * So sending the data fork of a regular inode is invalid.
 780          */
 781         ASSERT(!(S_ISREG(VFS_I(ip)->i_mode) && whichfork == XFS_DATA_FORK));
 782         ifp = xfs_ifork_ptr(ip, whichfork);
 783         ASSERT(ifp->if_format == XFS_DINODE_FMT_LOCAL);
 784
 785         if (!ifp->if_bytes) {
 786                 xfs_bmap_local_to_extents_empty(tp, ip, whichfork);
 787                 flags = XFS_ILOG_CORE;
 788                 goto done;
 789         }
 790
 791         flags = 0;
 792         error = 0;
 793         memset(&args, 0, sizeof(args));
 794         args.tp = tp;
 795         args.mp = ip->i_mount;
 796         args.total = total;
 797         args.minlen = args.maxlen = args.prod = 1;
 798         xfs_rmap_ino_owner(&args.oinfo, ip->i_ino, whichfork, 0);
 799
 800         /*
 801          * Allocate a block.  We know we need only one, since the
 802          * file currently fits in an inode.
 803          */
 804         args.total = total;
 805         args.minlen = args.maxlen = args.prod = 1;
 806         error = xfs_alloc_vextent_start_ag(&args,
 807                         XFS_INO_TO_FSB(args.mp, ip->i_ino));
 808         if (error)
 809                 goto done;
 810
 811         /* Can't fail, the space was reserved. */
 812         ASSERT(args.fsbno != NULLFSBLOCK);
 813         ASSERT(args.len == 1);
 814         error = xfs_trans_get_buf(tp, args.mp->m_ddev_targp,
 815                         XFS_FSB_TO_DADDR(args.mp, args.fsbno),
 816                         args.mp->m_bsize, 0, &bp);
 817         if (error)
 818                 goto done;
 819
 820         /*
 821          * Initialize the block, copy the data and log the remote buffer.
 822          *
 823          * The callout is responsible for logging because the remote format
 824          * might differ from the local format and thus we don't know how much to
 825          * log here. Note that init_fn must also set the buffer log item type
 826          * correctly.
 827          */
 828         init_fn(tp, bp, ip, ifp);
 829
 830         /* account for the change in fork size */
 831         xfs_idata_realloc(ip, -ifp->if_bytes, whichfork);
 832         xfs_bmap_local_to_extents_empty(tp, ip, whichfork);
 833         flags |= XFS_ILOG_CORE;
 834
 835         ifp->if_u1.if_root = NULL;
 836         ifp->if_height = 0;
 837
 838         rec.br_startoff = 0;
 839         rec.br_startblock = args.fsbno;
 840         rec.br_blockcount = 1;
 841         rec.br_state = XFS_EXT_NORM;
 842         xfs_iext_first(ifp, &icur);
 843         xfs_iext_insert(ip, &icur, &rec, 0);
 844
 845         ifp->if_nextents = 1;
 846         ip->i_nblocks = 1;
 847         xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_BCOUNT, 1L);
 848         flags |= xfs_ilog_fext(whichfork);
 849
 850 done:
 851         *logflagsp = flags;
 852         return error;
 853 }
 854
 855 /*
 856  * Called from xfs_bmap_add_attrfork to handle btree format files.
 857  */
 858 STATIC int                                      /* error */
 859 xfs_bmap_add_attrfork_btree(
 860         xfs_trans_t             *tp,            /* transaction pointer */
 861         xfs_inode_t             *ip,            /* incore inode pointer */
 862         int                     *flags)         /* inode logging flags */
 863 {
 864         struct xfs_btree_block  *block = ip->i_df.if_broot;
 865         struct xfs_btree_cur    *cur;           /* btree cursor */
 866         int                     error;          /* error return value */
 867         xfs_mount_t             *mp;            /* file system mount struct */
 868         int                     stat;           /* newroot status */
 869
 870         mp = ip->i_mount;
 871
 872         if (XFS_BMAP_BMDR_SPACE(block) <= xfs_inode_data_fork_size(ip))
 873                 *flags |= XFS_ILOG_DBROOT;
 874         else {
 875                 cur = xfs_bmbt_init_cursor(mp, tp, ip, XFS_DATA_FORK);
 876                 error = xfs_bmbt_lookup_first(cur, &stat);
 877                 if (error)
 878                         goto error0;
 879                 /* must be at least one entry */
 880                 if (XFS_IS_CORRUPT(mp, stat != 1)) {
 881                         error = -EFSCORRUPTED;
 882                         goto error0;
 883                 }
 884                 if ((error = xfs_btree_new_iroot(cur, flags, &stat)))
 885                         goto error0;
 886                 if (stat == 0) {
 887                         xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
 888                         return -ENOSPC;
 889                 }
 890                 cur->bc_ino.allocated = 0;
 891                 xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
 892         }
 893         return 0;
 894 error0:
 895         xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
 896         return error;
 897 }
 898
 899 /*
 900  * Called from xfs_bmap_add_attrfork to handle extents format files.
 901  */
 902 STATIC int                                      /* error */
 903 xfs_bmap_add_attrfork_extents(
 904         struct xfs_trans        *tp,            /* transaction pointer */
 905         struct xfs_inode        *ip,            /* incore inode pointer */
 906         int                     *flags)         /* inode logging flags */
 907 {
 908         struct xfs_btree_cur    *cur;           /* bmap btree cursor */
 909         int                     error;          /* error return value */
 910
 911         if (ip->i_df.if_nextents * sizeof(struct xfs_bmbt_rec) <=
 912             xfs_inode_data_fork_size(ip))
 913                 return 0;
 914         cur = NULL;
 915         error = xfs_bmap_extents_to_btree(tp, ip, &cur, 0, flags,
 916                                           XFS_DATA_FORK);
 917         if (cur) {
 918                 cur->bc_ino.allocated = 0;
 919                 xfs_btree_del_cursor(cur, error);
 920         }
 921         return error;
 922 }
 923
 924 /*
 925  * Called from xfs_bmap_add_attrfork to handle local format files. Each
 926  * different data fork content type needs a different callout to do the
 927  * conversion. Some are basic and only require special block initialisation
 928  * callouts for the data formating, others (directories) are so specialised they
 929  * handle everything themselves.
 930  *
 931  * XXX (dgc): investigate whether directory conversion can use the generic
 932  * formatting callout. It should be possible - it's just a very complex
 933  * formatter.
 934  */
 935 STATIC int                                      /* error */
 936 xfs_bmap_add_attrfork_local(
 937         struct xfs_trans        *tp,            /* transaction pointer */
 938         struct xfs_inode        *ip,            /* incore inode pointer */
 939         int                     *flags)         /* inode logging flags */
 940 {
 941         struct xfs_da_args      dargs;          /* args for dir/attr code */
 942
 943         if (ip->i_df.if_bytes <= xfs_inode_data_fork_size(ip))
 944                 return 0;
 945
 946         if (S_ISDIR(VFS_I(ip)->i_mode)) {
 947                 memset(&dargs, 0, sizeof(dargs));
 948                 dargs.geo = ip->i_mount->m_dir_geo;
 949                 dargs.dp = ip;
 950                 dargs.total = dargs.geo->fsbcount;
 951                 dargs.whichfork = XFS_DATA_FORK;
 952                 dargs.trans = tp;
 953                 return xfs_dir2_sf_to_block(&dargs);
 954         }
 955
 956         if (S_ISLNK(VFS_I(ip)->i_mode))
 957                 return xfs_bmap_local_to_extents(tp, ip, 1, flags,
 958                                                  XFS_DATA_FORK,
 959                                                  xfs_symlink_local_to_remote);
 960
 961         /* should only be called for types that support local format data */
 962         ASSERT(0);
 963         return -EFSCORRUPTED;
 964 }
 965
 966 /*
 967  * Set an inode attr fork offset based on the format of the data fork.
 968  */
 969 static int
 970 xfs_bmap_set_attrforkoff(
 971         struct xfs_inode        *ip,
 972         int                     size,
 973         int                     *version)
 974 {
 975         int                     default_size = xfs_default_attroffset(ip) >> 3;
 976
 977         switch (ip->i_df.if_format) {
 978         case XFS_DINODE_FMT_DEV:
 979                 ip->i_forkoff = default_size;
 980                 break;
 981         case XFS_DINODE_FMT_LOCAL:
 982         case XFS_DINODE_FMT_EXTENTS:
 983         case XFS_DINODE_FMT_BTREE:
 984                 ip->i_forkoff = xfs_attr_shortform_bytesfit(ip, size);
 985                 if (!ip->i_forkoff)
 986                         ip->i_forkoff = default_size;
 987                 else if (xfs_has_attr2(ip->i_mount) && version)
 988                         *version = 2;
 989                 break;
 990         default:
 991                 ASSERT(0);
 992                 return -EINVAL;
 993         }
 994
 995         return 0;
 996 }
 997
 998 /*
 999  * Convert inode from non-attributed to attributed.
1000  * Must not be in a transaction, ip must not be locked.
1001  */
1002 int                                             /* error code */
1003 xfs_bmap_add_attrfork(
1004         xfs_inode_t             *ip,            /* incore inode pointer */
1005         int                     size,           /* space new attribute needs */
1006         int                     rsvd)           /* xact may use reserved blks */
1007 {
1008         xfs_mount_t             *mp;            /* mount structure */
1009         xfs_trans_t             *tp;            /* transaction pointer */
1010         int                     blks;           /* space reservation */
1011         int                     version = 1;    /* superblock attr version */
1012         int                     logflags;       /* logging flags */
1013         int                     error;          /* error return value */
1014
1015         ASSERT(xfs_inode_has_attr_fork(ip) == 0);
1016
1017         mp = ip->i_mount;
1018         ASSERT(!XFS_NOT_DQATTACHED(mp, ip));
1019
1020         blks = XFS_ADDAFORK_SPACE_RES(mp);
1021
1022         error = xfs_trans_alloc_inode(ip, &M_RES(mp)->tr_addafork, blks, 0,
1023                         rsvd, &tp);
1024         if (error)
1025                 return error;
1026         if (xfs_inode_has_attr_fork(ip))
1027                 goto trans_cancel;
1028
1029         xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1030         error = xfs_bmap_set_attrforkoff(ip, size, &version);
1031         if (error)
1032                 goto trans_cancel;
1033
1034         xfs_ifork_init_attr(ip, XFS_DINODE_FMT_EXTENTS, 0);
1035         logflags = 0;
1036         switch (ip->i_df.if_format) {
1037         case XFS_DINODE_FMT_LOCAL:
1038                 error = xfs_bmap_add_attrfork_local(tp, ip, &logflags);
1039                 break;
1040         case XFS_DINODE_FMT_EXTENTS:
1041                 error = xfs_bmap_add_attrfork_extents(tp, ip, &logflags);
1042                 break;
1043         case XFS_DINODE_FMT_BTREE:
1044                 error = xfs_bmap_add_attrfork_btree(tp, ip, &logflags);
1045                 break;
1046         default:
1047                 error = 0;
1048                 break;
1049         }
1050         if (logflags)
1051                 xfs_trans_log_inode(tp, ip, logflags);
1052         if (error)
1053                 goto trans_cancel;
1054         if (!xfs_has_attr(mp) ||
1055            (!xfs_has_attr2(mp) && version == 2)) {
1056                 bool log_sb = false;
1057
1058                 spin_lock(&mp->m_sb_lock);
1059                 if (!xfs_has_attr(mp)) {
1060                         xfs_add_attr(mp);
1061                         log_sb = true;
1062                 }
1063                 if (!xfs_has_attr2(mp) && version == 2) {
1064                         xfs_add_attr2(mp);
1065                         log_sb = true;
1066                 }
1067                 spin_unlock(&mp->m_sb_lock);
1068                 if (log_sb)
1069                         xfs_log_sb(tp);
1070         }
1071
1072         error = xfs_trans_commit(tp);
1073         xfs_iunlock(ip, XFS_ILOCK_EXCL);
1074         return error;
1075
1076 trans_cancel:
1077         xfs_trans_cancel(tp);
1078         xfs_iunlock(ip, XFS_ILOCK_EXCL);
1079         return error;
1080 }
1081
1082 /*
1083  * Internal and external extent tree search functions.
1084  */
1085
1086 struct xfs_iread_state {
1087         struct xfs_iext_cursor  icur;
1088         xfs_extnum_t            loaded;
1089 };
1090
1091 int
1092 xfs_bmap_complain_bad_rec(
1093         struct xfs_inode                *ip,
1094         int                             whichfork,
1095         xfs_failaddr_t                  fa,
1096         const struct xfs_bmbt_irec      *irec)
1097 {
1098         struct xfs_mount                *mp = ip->i_mount;
1099         const char                      *forkname;
1100
1101         switch (whichfork) {
1102         case XFS_DATA_FORK:     forkname = "data"; break;
1103         case XFS_ATTR_FORK:     forkname = "attr"; break;
1104         case XFS_COW_FORK:      forkname = "CoW"; break;
1105         default:                forkname = "???"; break;
1106         }
1107
1108         xfs_warn(mp,
1109  "Bmap BTree record corruption in inode 0x%llx %s fork detected at %pS!",
1110                                 ip->i_ino, forkname, fa);
1111         xfs_warn(mp,
1112                 "Offset 0x%llx, start block 0x%llx, block count 0x%llx state 0x%x",
1113                 irec->br_startoff, irec->br_startblock, irec->br_blockcount,
1114                 irec->br_state);
1115
1116         return -EFSCORRUPTED;
1117 }
1118
1119 /* Stuff every bmbt record from this block into the incore extent map. */
1120 static int
1121 xfs_iread_bmbt_block(
1122         struct xfs_btree_cur    *cur,
1123         int                     level,
1124         void                    *priv)
1125 {
1126         struct xfs_iread_state  *ir = priv;
1127         struct xfs_mount        *mp = cur->bc_mp;
1128         struct xfs_inode        *ip = cur->bc_ino.ip;
1129         struct xfs_btree_block  *block;
1130         struct xfs_buf          *bp;
1131         struct xfs_bmbt_rec     *frp;
1132         xfs_extnum_t            num_recs;
1133         xfs_extnum_t            j;
1134         int                     whichfork = cur->bc_ino.whichfork;
1135         struct xfs_ifork        *ifp = xfs_ifork_ptr(ip, whichfork);
1136
1137         block = xfs_btree_get_block(cur, level, &bp);
1138
1139         /* Abort if we find more records than nextents. */
1140         num_recs = xfs_btree_get_numrecs(block);
1141         if (unlikely(ir->loaded + num_recs > ifp->if_nextents)) {
1142                 xfs_warn(ip->i_mount, "corrupt dinode %llu, (btree extents).",
1143                                 (unsigned long long)ip->i_ino);
1144                 xfs_inode_verifier_error(ip, -EFSCORRUPTED, __func__, block,
1145                                 sizeof(*block), __this_address);
1146                 return -EFSCORRUPTED;
1147         }
1148
1149         /* Copy records into the incore cache. */
1150         frp = XFS_BMBT_REC_ADDR(mp, block, 1);
1151         for (j = 0; j < num_recs; j++, frp++, ir->loaded++) {
1152                 struct xfs_bmbt_irec    new;
1153                 xfs_failaddr_t          fa;
1154
1155                 xfs_bmbt_disk_get_all(frp, &new);
1156                 fa = xfs_bmap_validate_extent(ip, whichfork, &new);
1157                 if (fa) {
1158                         xfs_inode_verifier_error(ip, -EFSCORRUPTED,
1159                                         "xfs_iread_extents(2)", frp,
1160                                         sizeof(*frp), fa);
1161                         return xfs_bmap_complain_bad_rec(ip, whichfork, fa,
1162                                         &new);
1163                 }
1164                 xfs_iext_insert(ip, &ir->icur, &new,
1165                                 xfs_bmap_fork_to_state(whichfork));
1166                 trace_xfs_read_extent(ip, &ir->icur,
1167                                 xfs_bmap_fork_to_state(whichfork), _THIS_IP_);
1168                 xfs_iext_next(ifp, &ir->icur);
1169         }
1170
1171         return 0;
1172 }
1173
1174 /*
1175  * Read in extents from a btree-format inode.
1176  */
1177 int
1178 xfs_iread_extents(
1179         struct xfs_trans        *tp,
1180         struct xfs_inode        *ip,
1181         int                     whichfork)
1182 {
1183         struct xfs_iread_state  ir;
1184         struct xfs_ifork        *ifp = xfs_ifork_ptr(ip, whichfork);
1185         struct xfs_mount        *mp = ip->i_mount;
1186         struct xfs_btree_cur    *cur;
1187         int                     error;
1188
1189         if (!xfs_need_iread_extents(ifp))
1190                 return 0;
1191
1192         ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
1193
1194         ir.loaded = 0;
1195         xfs_iext_first(ifp, &ir.icur);
1196         cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork);
1197         error = xfs_btree_visit_blocks(cur, xfs_iread_bmbt_block,
1198                         XFS_BTREE_VISIT_RECORDS, &ir);
1199         xfs_btree_del_cursor(cur, error);
1200         if (error)
1201                 goto out;
1202
1203         if (XFS_IS_CORRUPT(mp, ir.loaded != ifp->if_nextents)) {
1204                 error = -EFSCORRUPTED;
1205                 goto out;
1206         }
1207         ASSERT(ir.loaded == xfs_iext_count(ifp));
1208         /*
1209          * Use release semantics so that we can use acquire semantics in
1210          * xfs_need_iread_extents and be guaranteed to see a valid mapping tree
1211          * after that load.
1212          */
1213         smp_store_release(&ifp->if_needextents, 0);
1214         return 0;
1215 out:
1216         xfs_iext_destroy(ifp);
1217         return error;
1218 }
1219
1220 /*
1221  * Returns the relative block number of the first unused block(s) in the given
1222  * fork with at least "len" logically contiguous blocks free.  This is the
1223  * lowest-address hole if the fork has holes, else the first block past the end
1224  * of fork.  Return 0 if the fork is currently local (in-inode).
1225  */
1226 int                                             /* error */
1227 xfs_bmap_first_unused(
1228         struct xfs_trans        *tp,            /* transaction pointer */
1229         struct xfs_inode        *ip,            /* incore inode */
1230         xfs_extlen_t            len,            /* size of hole to find */
1231         xfs_fileoff_t           *first_unused,  /* unused block */
1232         int                     whichfork)      /* data or attr fork */
1233 {
1234         struct xfs_ifork        *ifp = xfs_ifork_ptr(ip, whichfork);
1235         struct xfs_bmbt_irec    got;
1236         struct xfs_iext_cursor  icur;
1237         xfs_fileoff_t           lastaddr = 0;
1238         xfs_fileoff_t           lowest, max;
1239         int                     error;
1240
1241         if (ifp->if_format == XFS_DINODE_FMT_LOCAL) {
1242                 *first_unused = 0;
1243                 return 0;
1244         }
1245
1246         ASSERT(xfs_ifork_has_extents(ifp));
1247
1248         error = xfs_iread_extents(tp, ip, whichfork);
1249         if (error)
1250                 return error;
1251
1252         lowest = max = *first_unused;
1253         for_each_xfs_iext(ifp, &icur, &got) {
1254                 /*
1255                  * See if the hole before this extent will work.
1256                  */
1257                 if (got.br_startoff >= lowest + len &&
1258                     got.br_startoff - max >= len)
1259                         break;
1260                 lastaddr = got.br_startoff + got.br_blockcount;
1261                 max = XFS_FILEOFF_MAX(lastaddr, lowest);
1262         }
1263
1264         *first_unused = max;
1265         return 0;
1266 }
1267
1268 /*
1269  * Returns the file-relative block number of the last block - 1 before
1270  * last_block (input value) in the file.
1271  * This is not based on i_size, it is based on the extent records.
1272  * Returns 0 for local files, as they do not have extent records.
1273  */
1274 int                                             /* error */
1275 xfs_bmap_last_before(
1276         struct xfs_trans        *tp,            /* transaction pointer */
1277         struct xfs_inode        *ip,            /* incore inode */
1278         xfs_fileoff_t           *last_block,    /* last block */
1279         int                     whichfork)      /* data or attr fork */
1280 {
1281         struct xfs_ifork        *ifp = xfs_ifork_ptr(ip, whichfork);
1282         struct xfs_bmbt_irec    got;
1283         struct xfs_iext_cursor  icur;
1284         int                     error;
1285
1286         switch (ifp->if_format) {
1287         case XFS_DINODE_FMT_LOCAL:
1288                 *last_block = 0;
1289                 return 0;
1290         case XFS_DINODE_FMT_BTREE:
1291         case XFS_DINODE_FMT_EXTENTS:
1292                 break;
1293         default:
1294                 ASSERT(0);
1295                 return -EFSCORRUPTED;
1296         }
1297
1298         error = xfs_iread_extents(tp, ip, whichfork);
1299         if (error)
1300                 return error;
1301
1302         if (!xfs_iext_lookup_extent_before(ip, ifp, last_block, &icur, &got))
1303                 *last_block = 0;
1304         return 0;
1305 }
1306
1307 int
1308 xfs_bmap_last_extent(
1309         struct xfs_trans        *tp,
1310         struct xfs_inode        *ip,
1311         int                     whichfork,
1312         struct xfs_bmbt_irec    *rec,
1313         int                     *is_empty)
1314 {
1315         struct xfs_ifork        *ifp = xfs_ifork_ptr(ip, whichfork);
1316         struct xfs_iext_cursor  icur;
1317         int                     error;
1318
1319         error = xfs_iread_extents(tp, ip, whichfork);
1320         if (error)
1321                 return error;
1322
1323         xfs_iext_last(ifp, &icur);
1324         if (!xfs_iext_get_extent(ifp, &icur, rec))
1325                 *is_empty = 1;
1326         else
1327                 *is_empty = 0;
1328         return 0;
1329 }
1330
1331 /*
1332  * Check the last inode extent to determine whether this allocation will result
1333  * in blocks being allocated at the end of the file. When we allocate new data
1334  * blocks at the end of the file which do not start at the previous data block,
1335  * we will try to align the new blocks at stripe unit boundaries.
1336  *
1337  * Returns 1 in bma->aeof if the file (fork) is empty as any new write will be
1338  * at, or past the EOF.
1339  */
1340 STATIC int
1341 xfs_bmap_isaeof(
1342         struct xfs_bmalloca     *bma,
1343         int                     whichfork)
1344 {
1345         struct xfs_bmbt_irec    rec;
1346         int                     is_empty;
1347         int                     error;
1348
1349         bma->aeof = false;
1350         error = xfs_bmap_last_extent(NULL, bma->ip, whichfork, &rec,
1351                                      &is_empty);
1352         if (error)
1353                 return error;
1354
1355         if (is_empty) {
1356                 bma->aeof = true;
1357                 return 0;
1358         }
1359
1360         /*
1361          * Check if we are allocation or past the last extent, or at least into
1362          * the last delayed allocated extent.
1363          */
1364         bma->aeof = bma->offset >= rec.br_startoff + rec.br_blockcount ||
1365                 (bma->offset >= rec.br_startoff &&
1366                  isnullstartblock(rec.br_startblock));
1367         return 0;
1368 }
1369
1370 /*
1371  * Returns the file-relative block number of the first block past eof in
1372  * the file.  This is not based on i_size, it is based on the extent records.
1373  * Returns 0 for local files, as they do not have extent records.
1374  */
1375 int
1376 xfs_bmap_last_offset(
1377         struct xfs_inode        *ip,
1378         xfs_fileoff_t           *last_block,
1379         int                     whichfork)
1380 {
1381         struct xfs_ifork        *ifp = xfs_ifork_ptr(ip, whichfork);
1382         struct xfs_bmbt_irec    rec;
1383         int                     is_empty;
1384         int                     error;
1385
1386         *last_block = 0;
1387
1388         if (ifp->if_format == XFS_DINODE_FMT_LOCAL)
1389                 return 0;
1390
1391         if (XFS_IS_CORRUPT(ip->i_mount, !xfs_ifork_has_extents(ifp)))
1392                 return -EFSCORRUPTED;
1393
1394         error = xfs_bmap_last_extent(NULL, ip, whichfork, &rec, &is_empty);
1395         if (error || is_empty)
1396                 return error;
1397
1398         *last_block = rec.br_startoff + rec.br_blockcount;
1399         return 0;
1400 }
1401
1402 /*
1403  * Extent tree manipulation functions used during allocation.
1404  */
1405
1406 /*
1407  * Convert a delayed allocation to a real allocation.
1408  */
1409 STATIC int                              /* error */
1410 xfs_bmap_add_extent_delay_real(
1411         struct xfs_bmalloca     *bma,
1412         int                     whichfork)
1413 {
1414         struct xfs_mount        *mp = bma->ip->i_mount;
1415         struct xfs_ifork        *ifp = xfs_ifork_ptr(bma->ip, whichfork);
1416         struct xfs_bmbt_irec    *new = &bma->got;
1417         int                     error;  /* error return value */
1418         int                     i;      /* temp state */
1419         xfs_fileoff_t           new_endoff;     /* end offset of new entry */
1420         xfs_bmbt_irec_t         r[3];   /* neighbor extent entries */
1421                                         /* left is 0, right is 1, prev is 2 */
1422         int                     rval=0; /* return value (logging flags) */
1423         uint32_t                state = xfs_bmap_fork_to_state(whichfork);
1424         xfs_filblks_t           da_new; /* new count del alloc blocks used */
1425         xfs_filblks_t           da_old; /* old count del alloc blocks used */
1426         xfs_filblks_t           temp=0; /* value for da_new calculations */
1427         int                     tmp_rval;       /* partial logging flags */
1428         struct xfs_bmbt_irec    old;
1429
1430         ASSERT(whichfork != XFS_ATTR_FORK);
1431         ASSERT(!isnullstartblock(new->br_startblock));
1432         ASSERT(!bma->cur ||
1433                (bma->cur->bc_ino.flags & XFS_BTCUR_BMBT_WASDEL));
1434
1435         XFS_STATS_INC(mp, xs_add_exlist);
1436
1437 #define LEFT            r[0]
1438 #define RIGHT           r[1]
1439 #define PREV            r[2]
1440
1441         /*
1442          * Set up a bunch of variables to make the tests simpler.
1443          */
1444         xfs_iext_get_extent(ifp, &bma->icur, &PREV);
1445         new_endoff = new->br_startoff + new->br_blockcount;
1446         ASSERT(isnullstartblock(PREV.br_startblock));
1447         ASSERT(PREV.br_startoff <= new->br_startoff);
1448         ASSERT(PREV.br_startoff + PREV.br_blockcount >= new_endoff);
1449
1450         da_old = startblockval(PREV.br_startblock);
1451         da_new = 0;
1452
1453         /*
1454          * Set flags determining what part of the previous delayed allocation
1455          * extent is being replaced by a real allocation.
1456          */
1457         if (PREV.br_startoff == new->br_startoff)
1458                 state |= BMAP_LEFT_FILLING;
1459         if (PREV.br_startoff + PREV.br_blockcount == new_endoff)
1460                 state |= BMAP_RIGHT_FILLING;
1461
1462         /*
1463          * Check and set flags if this segment has a left neighbor.
1464          * Don't set contiguous if the combined extent would be too large.
1465          */
1466         if (xfs_iext_peek_prev_extent(ifp, &bma->icur, &LEFT)) {
1467                 state |= BMAP_LEFT_VALID;
1468                 if (isnullstartblock(LEFT.br_startblock))
1469                         state |= BMAP_LEFT_DELAY;
1470         }
1471
1472         if ((state & BMAP_LEFT_VALID) && !(state & BMAP_LEFT_DELAY) &&
1473             LEFT.br_startoff + LEFT.br_blockcount == new->br_startoff &&
1474             LEFT.br_startblock + LEFT.br_blockcount == new->br_startblock &&
1475             LEFT.br_state == new->br_state &&
1476             LEFT.br_blockcount + new->br_blockcount <= XFS_MAX_BMBT_EXTLEN)
1477                 state |= BMAP_LEFT_CONTIG;
1478
1479         /*
1480          * Check and set flags if this segment has a right neighbor.
1481          * Don't set contiguous if the combined extent would be too large.
1482          * Also check for all-three-contiguous being too large.
1483          */
1484         if (xfs_iext_peek_next_extent(ifp, &bma->icur, &RIGHT)) {
1485                 state |= BMAP_RIGHT_VALID;
1486                 if (isnullstartblock(RIGHT.br_startblock))
1487                         state |= BMAP_RIGHT_DELAY;
1488         }
1489
1490         if ((state & BMAP_RIGHT_VALID) && !(state & BMAP_RIGHT_DELAY) &&
1491             new_endoff == RIGHT.br_startoff &&
1492             new->br_startblock + new->br_blockcount == RIGHT.br_startblock &&
1493             new->br_state == RIGHT.br_state &&
1494             new->br_blockcount + RIGHT.br_blockcount <= XFS_MAX_BMBT_EXTLEN &&
1495             ((state & (BMAP_LEFT_CONTIG | BMAP_LEFT_FILLING |
1496                        BMAP_RIGHT_FILLING)) !=
1497                       (BMAP_LEFT_CONTIG | BMAP_LEFT_FILLING |
1498                        BMAP_RIGHT_FILLING) ||
1499              LEFT.br_blockcount + new->br_blockcount + RIGHT.br_blockcount
1500                         <= XFS_MAX_BMBT_EXTLEN))
1501                 state |= BMAP_RIGHT_CONTIG;
1502
1503         error = 0;
1504         /*
1505          * Switch out based on the FILLING and CONTIG state bits.
1506          */
1507         switch (state & (BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG |
1508                          BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG)) {
1509         case BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG |
1510              BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG:
1511                 /*
1512                  * Filling in all of a previously delayed allocation extent.
1513                  * The left and right neighbors are both contiguous with new.
1514                  */
1515                 LEFT.br_blockcount += PREV.br_blockcount + RIGHT.br_blockcount;
1516
1517                 xfs_iext_remove(bma->ip, &bma->icur, state);
1518                 xfs_iext_remove(bma->ip, &bma->icur, state);
1519                 xfs_iext_prev(ifp, &bma->icur);
1520                 xfs_iext_update_extent(bma->ip, state, &bma->icur, &LEFT);
1521                 ifp->if_nextents--;
1522
1523                 if (bma->cur == NULL)
1524                         rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
1525                 else {
1526                         rval = XFS_ILOG_CORE;
1527                         error = xfs_bmbt_lookup_eq(bma->cur, &RIGHT, &i);
1528                         if (error)
1529                                 goto done;
1530                         if (XFS_IS_CORRUPT(mp, i != 1)) {
1531                                 error = -EFSCORRUPTED;
1532                                 goto done;
1533                         }
1534                         error = xfs_btree_delete(bma->cur, &i);
1535                         if (error)
1536                                 goto done;
1537                         if (XFS_IS_CORRUPT(mp, i != 1)) {
1538                                 error = -EFSCORRUPTED;
1539                                 goto done;
1540                         }
1541                         error = xfs_btree_decrement(bma->cur, 0, &i);
1542                         if (error)
1543                                 goto done;
1544                         if (XFS_IS_CORRUPT(mp, i != 1)) {
1545                                 error = -EFSCORRUPTED;
1546                                 goto done;
1547                         }
1548                         error = xfs_bmbt_update(bma->cur, &LEFT);
1549                         if (error)
1550                                 goto done;
1551                 }
1552                 break;
1553
1554         case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING | BMAP_LEFT_CONTIG:
1555                 /*
1556                  * Filling in all of a previously delayed allocation extent.
1557                  * The left neighbor is contiguous, the right is not.
1558                  */
1559                 old = LEFT;
1560                 LEFT.br_blockcount += PREV.br_blockcount;
1561
1562                 xfs_iext_remove(bma->ip, &bma->icur, state);
1563                 xfs_iext_prev(ifp, &bma->icur);
1564                 xfs_iext_update_extent(bma->ip, state, &bma->icur, &LEFT);
1565
1566                 if (bma->cur == NULL)
1567                         rval = XFS_ILOG_DEXT;
1568                 else {
1569                         rval = 0;
1570                         error = xfs_bmbt_lookup_eq(bma->cur, &old, &i);
1571                         if (error)
1572                                 goto done;
1573                         if (XFS_IS_CORRUPT(mp, i != 1)) {
1574                                 error = -EFSCORRUPTED;
1575                                 goto done;
1576                         }
1577                         error = xfs_bmbt_update(bma->cur, &LEFT);
1578                         if (error)
1579                                 goto done;
1580                 }
1581                 break;
1582
1583         case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG:
1584                 /*
1585                  * Filling in all of a previously delayed allocation extent.
1586                  * The right neighbor is contiguous, the left is not. Take care
1587                  * with delay -> unwritten extent allocation here because the
1588                  * delalloc record we are overwriting is always written.
1589                  */
1590                 PREV.br_startblock = new->br_startblock;
1591                 PREV.br_blockcount += RIGHT.br_blockcount;
1592                 PREV.br_state = new->br_state;
1593
1594                 xfs_iext_next(ifp, &bma->icur);
1595                 xfs_iext_remove(bma->ip, &bma->icur, state);
1596                 xfs_iext_prev(ifp, &bma->icur);
1597                 xfs_iext_update_extent(bma->ip, state, &bma->icur, &PREV);
1598
1599                 if (bma->cur == NULL)
1600                         rval = XFS_ILOG_DEXT;
1601                 else {
1602                         rval = 0;
1603                         error = xfs_bmbt_lookup_eq(bma->cur, &RIGHT, &i);
1604                         if (error)
1605                                 goto done;
1606                         if (XFS_IS_CORRUPT(mp, i != 1)) {
1607                                 error = -EFSCORRUPTED;
1608                                 goto done;
1609                         }
1610                         error = xfs_bmbt_update(bma->cur, &PREV);
1611                         if (error)
1612                                 goto done;
1613                 }
1614                 break;
1615
1616         case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING:
1617                 /*
1618                  * Filling in all of a previously delayed allocation extent.
1619                  * Neither the left nor right neighbors are contiguous with
1620                  * the new one.
1621                  */
1622                 PREV.br_startblock = new->br_startblock;
1623                 PREV.br_state = new->br_state;
1624                 xfs_iext_update_extent(bma->ip, state, &bma->icur, &PREV);
1625                 ifp->if_nextents++;
1626
1627                 if (bma->cur == NULL)
1628                         rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
1629                 else {
1630                         rval = XFS_ILOG_CORE;
1631                         error = xfs_bmbt_lookup_eq(bma->cur, new, &i);
1632                         if (error)
1633                                 goto done;
1634                         if (XFS_IS_CORRUPT(mp, i != 0)) {
1635                                 error = -EFSCORRUPTED;
1636                                 goto done;
1637                         }
1638                         error = xfs_btree_insert(bma->cur, &i);
1639                         if (error)
1640                                 goto done;
1641                         if (XFS_IS_CORRUPT(mp, i != 1)) {
1642                                 error = -EFSCORRUPTED;
1643                                 goto done;
1644                         }
1645                 }
1646                 break;
1647
1648         case BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG:
1649                 /*
1650                  * Filling in the first part of a previous delayed allocation.
1651                  * The left neighbor is contiguous.
1652                  */
1653                 old = LEFT;
1654                 temp = PREV.br_blockcount - new->br_blockcount;
1655                 da_new = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(bma->ip, temp),
1656                                 startblockval(PREV.br_startblock));
1657
1658                 LEFT.br_blockcount += new->br_blockcount;
1659
1660                 PREV.br_blockcount = temp;
1661                 PREV.br_startoff += new->br_blockcount;
1662                 PREV.br_startblock = nullstartblock(da_new);
1663
1664                 xfs_iext_update_extent(bma->ip, state, &bma->icur, &PREV);
1665                 xfs_iext_prev(ifp, &bma->icur);
1666                 xfs_iext_update_extent(bma->ip, state, &bma->icur, &LEFT);
1667
1668                 if (bma->cur == NULL)
1669                         rval = XFS_ILOG_DEXT;
1670                 else {
1671                         rval = 0;
1672                         error = xfs_bmbt_lookup_eq(bma->cur, &old, &i);
1673                         if (error)
1674                                 goto done;
1675                         if (XFS_IS_CORRUPT(mp, i != 1)) {
1676                                 error = -EFSCORRUPTED;
1677                                 goto done;
1678                         }
1679                         error = xfs_bmbt_update(bma->cur, &LEFT);
1680                         if (error)
1681                                 goto done;
1682                 }
1683                 break;
1684
1685         case BMAP_LEFT_FILLING:
1686                 /*
1687                  * Filling in the first part of a previous delayed allocation.
1688                  * The left neighbor is not contiguous.
1689                  */
1690                 xfs_iext_update_extent(bma->ip, state, &bma->icur, new);
1691                 ifp->if_nextents++;
1692
1693                 if (bma->cur == NULL)
1694                         rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
1695                 else {
1696                         rval = XFS_ILOG_CORE;
1697                         error = xfs_bmbt_lookup_eq(bma->cur, new, &i);
1698                         if (error)
1699                                 goto done;
1700                         if (XFS_IS_CORRUPT(mp, i != 0)) {
1701                                 error = -EFSCORRUPTED;
1702                                 goto done;
1703                         }
1704                         error = xfs_btree_insert(bma->cur, &i);
1705                         if (error)
1706                                 goto done;
1707                         if (XFS_IS_CORRUPT(mp, i != 1)) {
1708                                 error = -EFSCORRUPTED;
1709                                 goto done;
1710                         }
1711                 }
1712
1713                 if (xfs_bmap_needs_btree(bma->ip, whichfork)) {
1714                         error = xfs_bmap_extents_to_btree(bma->tp, bma->ip,
1715                                         &bma->cur, 1, &tmp_rval, whichfork);
1716                         rval |= tmp_rval;
1717                         if (error)
1718                                 goto done;
1719                 }
1720
1721                 temp = PREV.br_blockcount - new->br_blockcount;
1722                 da_new = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(bma->ip, temp),
1723                         startblockval(PREV.br_startblock) -
1724                         (bma->cur ? bma->cur->bc_ino.allocated : 0));
1725
1726                 PREV.br_startoff = new_endoff;
1727                 PREV.br_blockcount = temp;
1728                 PREV.br_startblock = nullstartblock(da_new);
1729                 xfs_iext_next(ifp, &bma->icur);
1730                 xfs_iext_insert(bma->ip, &bma->icur, &PREV, state);
1731                 xfs_iext_prev(ifp, &bma->icur);
1732                 break;
1733
1734         case BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG:
1735                 /*
1736                  * Filling in the last part of a previous delayed allocation.
1737                  * The right neighbor is contiguous with the new allocation.
1738                  */
1739                 old = RIGHT;
1740                 RIGHT.br_startoff = new->br_startoff;
1741                 RIGHT.br_startblock = new->br_startblock;
1742                 RIGHT.br_blockcount += new->br_blockcount;
1743
1744                 if (bma->cur == NULL)
1745                         rval = XFS_ILOG_DEXT;
1746                 else {
1747                         rval = 0;
1748                         error = xfs_bmbt_lookup_eq(bma->cur, &old, &i);
1749                         if (error)
1750                                 goto done;
1751                         if (XFS_IS_CORRUPT(mp, i != 1)) {
1752                                 error = -EFSCORRUPTED;
1753                                 goto done;
1754                         }
1755                         error = xfs_bmbt_update(bma->cur, &RIGHT);
1756                         if (error)
1757                                 goto done;
1758                 }
1759
1760                 temp = PREV.br_blockcount - new->br_blockcount;
1761                 da_new = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(bma->ip, temp),
1762                         startblockval(PREV.br_startblock));
1763
1764                 PREV.br_blockcount = temp;
1765                 PREV.br_startblock = nullstartblock(da_new);
1766
1767                 xfs_iext_update_extent(bma->ip, state, &bma->icur, &PREV);
1768                 xfs_iext_next(ifp, &bma->icur);
1769                 xfs_iext_update_extent(bma->ip, state, &bma->icur, &RIGHT);
1770                 break;
1771
1772         case BMAP_RIGHT_FILLING:
1773                 /*
1774                  * Filling in the last part of a previous delayed allocation.
1775                  * The right neighbor is not contiguous.
1776                  */
1777                 xfs_iext_update_extent(bma->ip, state, &bma->icur, new);
1778                 ifp->if_nextents++;
1779
1780                 if (bma->cur == NULL)
1781                         rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
1782                 else {
1783                         rval = XFS_ILOG_CORE;
1784                         error = xfs_bmbt_lookup_eq(bma->cur, new, &i);
1785                         if (error)
1786                                 goto done;
1787                         if (XFS_IS_CORRUPT(mp, i != 0)) {
1788                                 error = -EFSCORRUPTED;
1789                                 goto done;
1790                         }
1791                         error = xfs_btree_insert(bma->cur, &i);
1792                         if (error)
1793                                 goto done;
1794                         if (XFS_IS_CORRUPT(mp, i != 1)) {
1795                                 error = -EFSCORRUPTED;
1796                                 goto done;
1797                         }
1798                 }
1799
1800                 if (xfs_bmap_needs_btree(bma->ip, whichfork)) {
1801                         error = xfs_bmap_extents_to_btree(bma->tp, bma->ip,
1802                                 &bma->cur, 1, &tmp_rval, whichfork);
1803                         rval |= tmp_rval;
1804                         if (error)
1805                                 goto done;
1806                 }
1807
1808                 temp = PREV.br_blockcount - new->br_blockcount;
1809                 da_new = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(bma->ip, temp),
1810                         startblockval(PREV.br_startblock) -
1811                         (bma->cur ? bma->cur->bc_ino.allocated : 0));
1812
1813                 PREV.br_startblock = nullstartblock(da_new);
1814                 PREV.br_blockcount = temp;
1815                 xfs_iext_insert(bma->ip, &bma->icur, &PREV, state);
1816                 xfs_iext_next(ifp, &bma->icur);
1817                 break;
1818
1819         case 0:
1820                 /*
1821                  * Filling in the middle part of a previous delayed allocation.
1822                  * Contiguity is impossible here.
1823                  * This case is avoided almost all the time.
1824                  *
1825                  * We start with a delayed allocation:
1826                  *
1827                  * +ddddddddddddddddddddddddddddddddddddddddddddddddddddddd+
1828                  *  PREV @ idx
1829                  *
1830                  * and we are allocating:
1831                  *                     +rrrrrrrrrrrrrrrrr+
1832                  *                            new
1833                  *
1834                  * and we set it up for insertion as:
1835                  * +ddddddddddddddddddd+rrrrrrrrrrrrrrrrr+ddddddddddddddddd+
1836                  *                            new
1837                  *  PREV @ idx          LEFT              RIGHT
1838                  *                      inserted at idx + 1
1839                  */
1840                 old = PREV;
1841
1842                 /* LEFT is the new middle */
1843                 LEFT = *new;
1844
1845                 /* RIGHT is the new right */
1846                 RIGHT.br_state = PREV.br_state;
1847                 RIGHT.br_startoff = new_endoff;
1848                 RIGHT.br_blockcount =
1849                         PREV.br_startoff + PREV.br_blockcount - new_endoff;
1850                 RIGHT.br_startblock =
1851                         nullstartblock(xfs_bmap_worst_indlen(bma->ip,
1852                                         RIGHT.br_blockcount));
1853
1854                 /* truncate PREV */
1855                 PREV.br_blockcount = new->br_startoff - PREV.br_startoff;
1856                 PREV.br_startblock =
1857                         nullstartblock(xfs_bmap_worst_indlen(bma->ip,
1858                                         PREV.br_blockcount));
1859                 xfs_iext_update_extent(bma->ip, state, &bma->icur, &PREV);
1860
1861                 xfs_iext_next(ifp, &bma->icur);
1862                 xfs_iext_insert(bma->ip, &bma->icur, &RIGHT, state);
1863                 xfs_iext_insert(bma->ip, &bma->icur, &LEFT, state);
1864                 ifp->if_nextents++;
1865
1866                 if (bma->cur == NULL)
1867                         rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
1868                 else {
1869                         rval = XFS_ILOG_CORE;
1870                         error = xfs_bmbt_lookup_eq(bma->cur, new, &i);
1871                         if (error)
1872                                 goto done;
1873                         if (XFS_IS_CORRUPT(mp, i != 0)) {
1874                                 error = -EFSCORRUPTED;
1875                                 goto done;
1876                         }
1877                         error = xfs_btree_insert(bma->cur, &i);
1878                         if (error)
1879                                 goto done;
1880                         if (XFS_IS_CORRUPT(mp, i != 1)) {
1881                                 error = -EFSCORRUPTED;
1882                                 goto done;
1883                         }
1884                 }
1885
1886                 if (xfs_bmap_needs_btree(bma->ip, whichfork)) {
1887                         error = xfs_bmap_extents_to_btree(bma->tp, bma->ip,
1888                                         &bma->cur, 1, &tmp_rval, whichfork);
1889                         rval |= tmp_rval;
1890                         if (error)
1891                                 goto done;
1892                 }
1893
1894                 da_new = startblockval(PREV.br_startblock) +
1895                          startblockval(RIGHT.br_startblock);
1896                 break;
1897
1898         case BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
1899         case BMAP_RIGHT_FILLING | BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
1900         case BMAP_LEFT_FILLING | BMAP_RIGHT_CONTIG:
1901         case BMAP_RIGHT_FILLING | BMAP_LEFT_CONTIG:
1902         case BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
1903         case BMAP_LEFT_CONTIG:
1904         case BMAP_RIGHT_CONTIG:
1905                 /*
1906                  * These cases are all impossible.
1907                  */
1908                 ASSERT(0);
1909         }
1910
1911         /* add reverse mapping unless caller opted out */
1912         if (!(bma->flags & XFS_BMAPI_NORMAP))
1913                 xfs_rmap_map_extent(bma->tp, bma->ip, whichfork, new);
1914
1915         /* convert to a btree if necessary */
1916         if (xfs_bmap_needs_btree(bma->ip, whichfork)) {
1917                 int     tmp_logflags;   /* partial log flag return val */
1918
1919                 ASSERT(bma->cur == NULL);
1920                 error = xfs_bmap_extents_to_btree(bma->tp, bma->ip,
1921                                 &bma->cur, da_old > 0, &tmp_logflags,
1922                                 whichfork);
1923                 bma->logflags |= tmp_logflags;
1924                 if (error)
1925                         goto done;
1926         }
1927
1928         if (da_new != da_old)
1929                 xfs_mod_delalloc(mp, (int64_t)da_new - da_old);
1930
1931         if (bma->cur) {
1932                 da_new += bma->cur->bc_ino.allocated;
1933                 bma->cur->bc_ino.allocated = 0;
1934         }
1935
1936         /* adjust for changes in reserved delayed indirect blocks */
1937         if (da_new != da_old) {
1938                 ASSERT(state == 0 || da_new < da_old);
1939                 error = xfs_mod_fdblocks(mp, (int64_t)(da_old - da_new),
1940                                 false);
1941         }
1942
1943         xfs_bmap_check_leaf_extents(bma->cur, bma->ip, whichfork);
1944 done:
1945         if (whichfork != XFS_COW_FORK)
1946                 bma->logflags |= rval;
1947         return error;
1948 #undef  LEFT
1949 #undef  RIGHT
1950 #undef  PREV
1951 }
1952
1953 /*
1954  * Convert an unwritten allocation to a real allocation or vice versa.
1955  */
1956 int                                     /* error */
1957 xfs_bmap_add_extent_unwritten_real(
1958         struct xfs_trans        *tp,
1959         xfs_inode_t             *ip,    /* incore inode pointer */
1960         int                     whichfork,
1961         struct xfs_iext_cursor  *icur,
1962         struct xfs_btree_cur    **curp, /* if *curp is null, not a btree */
1963         xfs_bmbt_irec_t         *new,   /* new data to add to file extents */
1964         int                     *logflagsp) /* inode logging flags */
1965 {
1966         struct xfs_btree_cur    *cur;   /* btree cursor */
1967         int                     error;  /* error return value */
1968         int                     i;      /* temp state */
1969         struct xfs_ifork        *ifp;   /* inode fork pointer */
1970         xfs_fileoff_t           new_endoff;     /* end offset of new entry */
1971         xfs_bmbt_irec_t         r[3];   /* neighbor extent entries */
1972                                         /* left is 0, right is 1, prev is 2 */
1973         int                     rval=0; /* return value (logging flags) */
1974         uint32_t                state = xfs_bmap_fork_to_state(whichfork);
1975         struct xfs_mount        *mp = ip->i_mount;
1976         struct xfs_bmbt_irec    old;
1977
1978         *logflagsp = 0;
1979
1980         cur = *curp;
1981         ifp = xfs_ifork_ptr(ip, whichfork);
1982
1983         ASSERT(!isnullstartblock(new->br_startblock));
1984
1985         XFS_STATS_INC(mp, xs_add_exlist);
1986
1987 #define LEFT            r[0]
1988 #define RIGHT           r[1]
1989 #define PREV            r[2]
1990
1991         /*
1992          * Set up a bunch of variables to make the tests simpler.
1993          */
1994         error = 0;
1995         xfs_iext_get_extent(ifp, icur, &PREV);
1996         ASSERT(new->br_state != PREV.br_state);
1997         new_endoff = new->br_startoff + new->br_blockcount;
1998         ASSERT(PREV.br_startoff <= new->br_startoff);
1999         ASSERT(PREV.br_startoff + PREV.br_blockcount >= new_endoff);
2000
2001         /*
2002          * Set flags determining what part of the previous oldext allocation
2003          * extent is being replaced by a newext allocation.
2004          */
2005         if (PREV.br_startoff == new->br_startoff)
2006                 state |= BMAP_LEFT_FILLING;
2007         if (PREV.br_startoff + PREV.br_blockcount == new_endoff)
2008                 state |= BMAP_RIGHT_FILLING;
2009
2010         /*
2011          * Check and set flags if this segment has a left neighbor.
2012          * Don't set contiguous if the combined extent would be too large.
2013          */
2014         if (xfs_iext_peek_prev_extent(ifp, icur, &LEFT)) {
2015                 state |= BMAP_LEFT_VALID;
2016                 if (isnullstartblock(LEFT.br_startblock))
2017                         state |= BMAP_LEFT_DELAY;
2018         }
2019
2020         if ((state & BMAP_LEFT_VALID) && !(state & BMAP_LEFT_DELAY) &&
2021             LEFT.br_startoff + LEFT.br_blockcount == new->br_startoff &&
2022             LEFT.br_startblock + LEFT.br_blockcount == new->br_startblock &&
2023             LEFT.br_state == new->br_state &&
2024             LEFT.br_blockcount + new->br_blockcount <= XFS_MAX_BMBT_EXTLEN)
2025                 state |= BMAP_LEFT_CONTIG;
2026
2027         /*
2028          * Check and set flags if this segment has a right neighbor.
2029          * Don't set contiguous if the combined extent would be too large.
2030          * Also check for all-three-contiguous being too large.
2031          */
2032         if (xfs_iext_peek_next_extent(ifp, icur, &RIGHT)) {
2033                 state |= BMAP_RIGHT_VALID;
2034                 if (isnullstartblock(RIGHT.br_startblock))
2035                         state |= BMAP_RIGHT_DELAY;
2036         }
2037
2038         if ((state & BMAP_RIGHT_VALID) && !(state & BMAP_RIGHT_DELAY) &&
2039             new_endoff == RIGHT.br_startoff &&
2040             new->br_startblock + new->br_blockcount == RIGHT.br_startblock &&
2041             new->br_state == RIGHT.br_state &&
2042             new->br_blockcount + RIGHT.br_blockcount <= XFS_MAX_BMBT_EXTLEN &&
2043             ((state & (BMAP_LEFT_CONTIG | BMAP_LEFT_FILLING |
2044                        BMAP_RIGHT_FILLING)) !=
2045                       (BMAP_LEFT_CONTIG | BMAP_LEFT_FILLING |
2046                        BMAP_RIGHT_FILLING) ||
2047              LEFT.br_blockcount + new->br_blockcount + RIGHT.br_blockcount
2048                         <= XFS_MAX_BMBT_EXTLEN))
2049                 state |= BMAP_RIGHT_CONTIG;
2050
2051         /*
2052          * Switch out based on the FILLING and CONTIG state bits.
2053          */
2054         switch (state & (BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG |
2055                          BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG)) {
2056         case BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG |
2057              BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG:
2058                 /*
2059                  * Setting all of a previous oldext extent to newext.
2060                  * The left and right neighbors are both contiguous with new.
2061                  */
2062                 LEFT.br_blockcount += PREV.br_blockcount + RIGHT.br_blockcount;
2063
2064                 xfs_iext_remove(ip, icur, state);
2065                 xfs_iext_remove(ip, icur, state);
2066                 xfs_iext_prev(ifp, icur);
2067                 xfs_iext_update_extent(ip, state, icur, &LEFT);
2068                 ifp->if_nextents -= 2;
2069                 if (cur == NULL)
2070                         rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
2071                 else {
2072                         rval = XFS_ILOG_CORE;
2073                         error = xfs_bmbt_lookup_eq(cur, &RIGHT, &i);
2074                         if (error)
2075                                 goto done;
2076                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2077                                 error = -EFSCORRUPTED;
2078                                 goto done;
2079                         }
2080                         if ((error = xfs_btree_delete(cur, &i)))
2081                                 goto done;
2082                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2083                                 error = -EFSCORRUPTED;
2084                                 goto done;
2085                         }
2086                         if ((error = xfs_btree_decrement(cur, 0, &i)))
2087                                 goto done;
2088                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2089                                 error = -EFSCORRUPTED;
2090                                 goto done;
2091                         }
2092                         if ((error = xfs_btree_delete(cur, &i)))
2093                                 goto done;
2094                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2095                                 error = -EFSCORRUPTED;
2096                                 goto done;
2097                         }
2098                         if ((error = xfs_btree_decrement(cur, 0, &i)))
2099                                 goto done;
2100                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2101                                 error = -EFSCORRUPTED;
2102                                 goto done;
2103                         }
2104                         error = xfs_bmbt_update(cur, &LEFT);
2105                         if (error)
2106                                 goto done;
2107                 }
2108                 break;
2109
2110         case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING | BMAP_LEFT_CONTIG:
2111                 /*
2112                  * Setting all of a previous oldext extent to newext.
2113                  * The left neighbor is contiguous, the right is not.
2114                  */
2115                 LEFT.br_blockcount += PREV.br_blockcount;
2116
2117                 xfs_iext_remove(ip, icur, state);
2118                 xfs_iext_prev(ifp, icur);
2119                 xfs_iext_update_extent(ip, state, icur, &LEFT);
2120                 ifp->if_nextents--;
2121                 if (cur == NULL)
2122                         rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
2123                 else {
2124                         rval = XFS_ILOG_CORE;
2125                         error = xfs_bmbt_lookup_eq(cur, &PREV, &i);
2126                         if (error)
2127                                 goto done;
2128                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2129                                 error = -EFSCORRUPTED;
2130                                 goto done;
2131                         }
2132                         if ((error = xfs_btree_delete(cur, &i)))
2133                                 goto done;
2134                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2135                                 error = -EFSCORRUPTED;
2136                                 goto done;
2137                         }
2138                         if ((error = xfs_btree_decrement(cur, 0, &i)))
2139                                 goto done;
2140                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2141                                 error = -EFSCORRUPTED;
2142                                 goto done;
2143                         }
2144                         error = xfs_bmbt_update(cur, &LEFT);
2145                         if (error)
2146                                 goto done;
2147                 }
2148                 break;
2149
2150         case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG:
2151                 /*
2152                  * Setting all of a previous oldext extent to newext.
2153                  * The right neighbor is contiguous, the left is not.
2154                  */
2155                 PREV.br_blockcount += RIGHT.br_blockcount;
2156                 PREV.br_state = new->br_state;
2157
2158                 xfs_iext_next(ifp, icur);
2159                 xfs_iext_remove(ip, icur, state);
2160                 xfs_iext_prev(ifp, icur);
2161                 xfs_iext_update_extent(ip, state, icur, &PREV);
2162                 ifp->if_nextents--;
2163
2164                 if (cur == NULL)
2165                         rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
2166                 else {
2167                         rval = XFS_ILOG_CORE;
2168                         error = xfs_bmbt_lookup_eq(cur, &RIGHT, &i);
2169                         if (error)
2170                                 goto done;
2171                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2172                                 error = -EFSCORRUPTED;
2173                                 goto done;
2174                         }
2175                         if ((error = xfs_btree_delete(cur, &i)))
2176                                 goto done;
2177                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2178                                 error = -EFSCORRUPTED;
2179                                 goto done;
2180                         }
2181                         if ((error = xfs_btree_decrement(cur, 0, &i)))
2182                                 goto done;
2183                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2184                                 error = -EFSCORRUPTED;
2185                                 goto done;
2186                         }
2187                         error = xfs_bmbt_update(cur, &PREV);
2188                         if (error)
2189                                 goto done;
2190                 }
2191                 break;
2192
2193         case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING:
2194                 /*
2195                  * Setting all of a previous oldext extent to newext.
2196                  * Neither the left nor right neighbors are contiguous with
2197                  * the new one.
2198                  */
2199                 PREV.br_state = new->br_state;
2200                 xfs_iext_update_extent(ip, state, icur, &PREV);
2201
2202                 if (cur == NULL)
2203                         rval = XFS_ILOG_DEXT;
2204                 else {
2205                         rval = 0;
2206                         error = xfs_bmbt_lookup_eq(cur, new, &i);
2207                         if (error)
2208                                 goto done;
2209                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2210                                 error = -EFSCORRUPTED;
2211                                 goto done;
2212                         }
2213                         error = xfs_bmbt_update(cur, &PREV);
2214                         if (error)
2215                                 goto done;
2216                 }
2217                 break;
2218
2219         case BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG:
2220                 /*
2221                  * Setting the first part of a previous oldext extent to newext.
2222                  * The left neighbor is contiguous.
2223                  */
2224                 LEFT.br_blockcount += new->br_blockcount;
2225
2226                 old = PREV;
2227                 PREV.br_startoff += new->br_blockcount;
2228                 PREV.br_startblock += new->br_blockcount;
2229                 PREV.br_blockcount -= new->br_blockcount;
2230
2231                 xfs_iext_update_extent(ip, state, icur, &PREV);
2232                 xfs_iext_prev(ifp, icur);
2233                 xfs_iext_update_extent(ip, state, icur, &LEFT);
2234
2235                 if (cur == NULL)
2236                         rval = XFS_ILOG_DEXT;
2237                 else {
2238                         rval = 0;
2239                         error = xfs_bmbt_lookup_eq(cur, &old, &i);
2240                         if (error)
2241                                 goto done;
2242                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2243                                 error = -EFSCORRUPTED;
2244                                 goto done;
2245                         }
2246                         error = xfs_bmbt_update(cur, &PREV);
2247                         if (error)
2248                                 goto done;
2249                         error = xfs_btree_decrement(cur, 0, &i);
2250                         if (error)
2251                                 goto done;
2252                         error = xfs_bmbt_update(cur, &LEFT);
2253                         if (error)
2254                                 goto done;
2255                 }
2256                 break;
2257
2258         case BMAP_LEFT_FILLING:
2259                 /*
2260                  * Setting the first part of a previous oldext extent to newext.
2261                  * The left neighbor is not contiguous.
2262                  */
2263                 old = PREV;
2264                 PREV.br_startoff += new->br_blockcount;
2265                 PREV.br_startblock += new->br_blockcount;
2266                 PREV.br_blockcount -= new->br_blockcount;
2267
2268                 xfs_iext_update_extent(ip, state, icur, &PREV);
2269                 xfs_iext_insert(ip, icur, new, state);
2270                 ifp->if_nextents++;
2271
2272                 if (cur == NULL)
2273                         rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
2274                 else {
2275                         rval = XFS_ILOG_CORE;
2276                         error = xfs_bmbt_lookup_eq(cur, &old, &i);
2277                         if (error)
2278                                 goto done;
2279                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2280                                 error = -EFSCORRUPTED;
2281                                 goto done;
2282                         }
2283                         error = xfs_bmbt_update(cur, &PREV);
2284                         if (error)
2285                                 goto done;
2286                         cur->bc_rec.b = *new;
2287                         if ((error = xfs_btree_insert(cur, &i)))
2288                                 goto done;
2289                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2290                                 error = -EFSCORRUPTED;
2291                                 goto done;
2292                         }
2293                 }
2294                 break;
2295
2296         case BMAP_RIGHT_FILLING | BMAP_RIGHT_CONTIG:
2297                 /*
2298                  * Setting the last part of a previous oldext extent to newext.
2299                  * The right neighbor is contiguous with the new allocation.
2300                  */
2301                 old = PREV;
2302                 PREV.br_blockcount -= new->br_blockcount;
2303
2304                 RIGHT.br_startoff = new->br_startoff;
2305                 RIGHT.br_startblock = new->br_startblock;
2306                 RIGHT.br_blockcount += new->br_blockcount;
2307
2308                 xfs_iext_update_extent(ip, state, icur, &PREV);
2309                 xfs_iext_next(ifp, icur);
2310                 xfs_iext_update_extent(ip, state, icur, &RIGHT);
2311
2312                 if (cur == NULL)
2313                         rval = XFS_ILOG_DEXT;
2314                 else {
2315                         rval = 0;
2316                         error = xfs_bmbt_lookup_eq(cur, &old, &i);
2317                         if (error)
2318                                 goto done;
2319                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2320                                 error = -EFSCORRUPTED;
2321                                 goto done;
2322                         }
2323                         error = xfs_bmbt_update(cur, &PREV);
2324                         if (error)
2325                                 goto done;
2326                         error = xfs_btree_increment(cur, 0, &i);
2327                         if (error)
2328                                 goto done;
2329                         error = xfs_bmbt_update(cur, &RIGHT);
2330                         if (error)
2331                                 goto done;
2332                 }
2333                 break;
2334
2335         case BMAP_RIGHT_FILLING:
2336                 /*
2337                  * Setting the last part of a previous oldext extent to newext.
2338                  * The right neighbor is not contiguous.
2339                  */
2340                 old = PREV;
2341                 PREV.br_blockcount -= new->br_blockcount;
2342
2343                 xfs_iext_update_extent(ip, state, icur, &PREV);
2344                 xfs_iext_next(ifp, icur);
2345                 xfs_iext_insert(ip, icur, new, state);
2346                 ifp->if_nextents++;
2347
2348                 if (cur == NULL)
2349                         rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
2350                 else {
2351                         rval = XFS_ILOG_CORE;
2352                         error = xfs_bmbt_lookup_eq(cur, &old, &i);
2353                         if (error)
2354                                 goto done;
2355                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2356                                 error = -EFSCORRUPTED;
2357                                 goto done;
2358                         }
2359                         error = xfs_bmbt_update(cur, &PREV);
2360                         if (error)
2361                                 goto done;
2362                         error = xfs_bmbt_lookup_eq(cur, new, &i);
2363                         if (error)
2364                                 goto done;
2365                         if (XFS_IS_CORRUPT(mp, i != 0)) {
2366                                 error = -EFSCORRUPTED;
2367                                 goto done;
2368                         }
2369                         if ((error = xfs_btree_insert(cur, &i)))
2370                                 goto done;
2371                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2372                                 error = -EFSCORRUPTED;
2373                                 goto done;
2374                         }
2375                 }
2376                 break;
2377
2378         case 0:
2379                 /*
2380                  * Setting the middle part of a previous oldext extent to
2381                  * newext.  Contiguity is impossible here.
2382                  * One extent becomes three extents.
2383                  */
2384                 old = PREV;
2385                 PREV.br_blockcount = new->br_startoff - PREV.br_startoff;
2386
2387                 r[0] = *new;
2388                 r[1].br_startoff = new_endoff;
2389                 r[1].br_blockcount =
2390                         old.br_startoff + old.br_blockcount - new_endoff;
2391                 r[1].br_startblock = new->br_startblock + new->br_blockcount;
2392                 r[1].br_state = PREV.br_state;
2393
2394                 xfs_iext_update_extent(ip, state, icur, &PREV);
2395                 xfs_iext_next(ifp, icur);
2396                 xfs_iext_insert(ip, icur, &r[1], state);
2397                 xfs_iext_insert(ip, icur, &r[0], state);
2398                 ifp->if_nextents += 2;
2399
2400                 if (cur == NULL)
2401                         rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
2402                 else {
2403                         rval = XFS_ILOG_CORE;
2404                         error = xfs_bmbt_lookup_eq(cur, &old, &i);
2405                         if (error)
2406                                 goto done;
2407                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2408                                 error = -EFSCORRUPTED;
2409                                 goto done;
2410                         }
2411                         /* new right extent - oldext */
2412                         error = xfs_bmbt_update(cur, &r[1]);
2413                         if (error)
2414                                 goto done;
2415                         /* new left extent - oldext */
2416                         cur->bc_rec.b = PREV;
2417                         if ((error = xfs_btree_insert(cur, &i)))
2418                                 goto done;
2419                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2420                                 error = -EFSCORRUPTED;
2421                                 goto done;
2422                         }
2423                         /*
2424                          * Reset the cursor to the position of the new extent
2425                          * we are about to insert as we can't trust it after
2426                          * the previous insert.
2427                          */
2428                         error = xfs_bmbt_lookup_eq(cur, new, &i);
2429                         if (error)
2430                                 goto done;
2431                         if (XFS_IS_CORRUPT(mp, i != 0)) {
2432                                 error = -EFSCORRUPTED;
2433                                 goto done;
2434                         }
2435                         /* new middle extent - newext */
2436                         if ((error = xfs_btree_insert(cur, &i)))
2437                                 goto done;
2438                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2439                                 error = -EFSCORRUPTED;
2440                                 goto done;
2441                         }
2442                 }
2443                 break;
2444
2445         case BMAP_LEFT_FILLING | BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
2446         case BMAP_RIGHT_FILLING | BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
2447         case BMAP_LEFT_FILLING | BMAP_RIGHT_CONTIG:
2448         case BMAP_RIGHT_FILLING | BMAP_LEFT_CONTIG:
2449         case BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
2450         case BMAP_LEFT_CONTIG:
2451         case BMAP_RIGHT_CONTIG:
2452                 /*
2453                  * These cases are all impossible.
2454                  */
2455                 ASSERT(0);
2456         }
2457
2458         /* update reverse mappings */
2459         xfs_rmap_convert_extent(mp, tp, ip, whichfork, new);
2460
2461         /* convert to a btree if necessary */
2462         if (xfs_bmap_needs_btree(ip, whichfork)) {
2463                 int     tmp_logflags;   /* partial log flag return val */
2464
2465                 ASSERT(cur == NULL);
2466                 error = xfs_bmap_extents_to_btree(tp, ip, &cur, 0,
2467                                 &tmp_logflags, whichfork);
2468                 *logflagsp |= tmp_logflags;
2469                 if (error)
2470                         goto done;
2471         }
2472
2473         /* clear out the allocated field, done with it now in any case. */
2474         if (cur) {
2475                 cur->bc_ino.allocated = 0;
2476                 *curp = cur;
2477         }
2478
2479         xfs_bmap_check_leaf_extents(*curp, ip, whichfork);
2480 done:
2481         *logflagsp |= rval;
2482         return error;
2483 #undef  LEFT
2484 #undef  RIGHT
2485 #undef  PREV
2486 }
2487
2488 /*
2489  * Convert a hole to a delayed allocation.
2490  */
2491 STATIC void
2492 xfs_bmap_add_extent_hole_delay(
2493         xfs_inode_t             *ip,    /* incore inode pointer */
2494         int                     whichfork,
2495         struct xfs_iext_cursor  *icur,
2496         xfs_bmbt_irec_t         *new)   /* new data to add to file extents */
2497 {
2498         struct xfs_ifork        *ifp;   /* inode fork pointer */
2499         xfs_bmbt_irec_t         left;   /* left neighbor extent entry */
2500         xfs_filblks_t           newlen=0;       /* new indirect size */
2501         xfs_filblks_t           oldlen=0;       /* old indirect size */
2502         xfs_bmbt_irec_t         right;  /* right neighbor extent entry */
2503         uint32_t                state = xfs_bmap_fork_to_state(whichfork);
2504         xfs_filblks_t           temp;    /* temp for indirect calculations */
2505
2506         ifp = xfs_ifork_ptr(ip, whichfork);
2507         ASSERT(isnullstartblock(new->br_startblock));
2508
2509         /*
2510          * Check and set flags if this segment has a left neighbor
2511          */
2512         if (xfs_iext_peek_prev_extent(ifp, icur, &left)) {
2513                 state |= BMAP_LEFT_VALID;
2514                 if (isnullstartblock(left.br_startblock))
2515                         state |= BMAP_LEFT_DELAY;
2516         }
2517
2518         /*
2519          * Check and set flags if the current (right) segment exists.
2520          * If it doesn't exist, we're converting the hole at end-of-file.
2521          */
2522         if (xfs_iext_get_extent(ifp, icur, &right)) {
2523                 state |= BMAP_RIGHT_VALID;
2524                 if (isnullstartblock(right.br_startblock))
2525                         state |= BMAP_RIGHT_DELAY;
2526         }
2527
2528         /*
2529          * Set contiguity flags on the left and right neighbors.
2530          * Don't let extents get too large, even if the pieces are contiguous.
2531          */
2532         if ((state & BMAP_LEFT_VALID) && (state & BMAP_LEFT_DELAY) &&
2533             left.br_startoff + left.br_blockcount == new->br_startoff &&
2534             left.br_blockcount + new->br_blockcount <= XFS_MAX_BMBT_EXTLEN)
2535                 state |= BMAP_LEFT_CONTIG;
2536
2537         if ((state & BMAP_RIGHT_VALID) && (state & BMAP_RIGHT_DELAY) &&
2538             new->br_startoff + new->br_blockcount == right.br_startoff &&
2539             new->br_blockcount + right.br_blockcount <= XFS_MAX_BMBT_EXTLEN &&
2540             (!(state & BMAP_LEFT_CONTIG) ||
2541              (left.br_blockcount + new->br_blockcount +
2542               right.br_blockcount <= XFS_MAX_BMBT_EXTLEN)))
2543                 state |= BMAP_RIGHT_CONTIG;
2544
2545         /*
2546          * Switch out based on the contiguity flags.
2547          */
2548         switch (state & (BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG)) {
2549         case BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
2550                 /*
2551                  * New allocation is contiguous with delayed allocations
2552                  * on the left and on the right.
2553                  * Merge all three into a single extent record.
2554                  */
2555                 temp = left.br_blockcount + new->br_blockcount +
2556                         right.br_blockcount;
2557
2558                 oldlen = startblockval(left.br_startblock) +
2559                         startblockval(new->br_startblock) +
2560                         startblockval(right.br_startblock);
2561                 newlen = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip, temp),
2562                                          oldlen);
2563                 left.br_startblock = nullstartblock(newlen);
2564                 left.br_blockcount = temp;
2565
2566                 xfs_iext_remove(ip, icur, state);
2567                 xfs_iext_prev(ifp, icur);
2568                 xfs_iext_update_extent(ip, state, icur, &left);
2569                 break;
2570
2571         case BMAP_LEFT_CONTIG:
2572                 /*
2573                  * New allocation is contiguous with a delayed allocation
2574                  * on the left.
2575                  * Merge the new allocation with the left neighbor.
2576                  */
2577                 temp = left.br_blockcount + new->br_blockcount;
2578
2579                 oldlen = startblockval(left.br_startblock) +
2580                         startblockval(new->br_startblock);
2581                 newlen = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip, temp),
2582                                          oldlen);
2583                 left.br_blockcount = temp;
2584                 left.br_startblock = nullstartblock(newlen);
2585
2586                 xfs_iext_prev(ifp, icur);
2587                 xfs_iext_update_extent(ip, state, icur, &left);
2588                 break;
2589
2590         case BMAP_RIGHT_CONTIG:
2591                 /*
2592                  * New allocation is contiguous with a delayed allocation
2593                  * on the right.
2594                  * Merge the new allocation with the right neighbor.
2595                  */
2596                 temp = new->br_blockcount + right.br_blockcount;
2597                 oldlen = startblockval(new->br_startblock) +
2598                         startblockval(right.br_startblock);
2599                 newlen = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip, temp),
2600                                          oldlen);
2601                 right.br_startoff = new->br_startoff;
2602                 right.br_startblock = nullstartblock(newlen);
2603                 right.br_blockcount = temp;
2604                 xfs_iext_update_extent(ip, state, icur, &right);
2605                 break;
2606
2607         case 0:
2608                 /*
2609                  * New allocation is not contiguous with another
2610                  * delayed allocation.
2611                  * Insert a new entry.
2612                  */
2613                 oldlen = newlen = 0;
2614                 xfs_iext_insert(ip, icur, new, state);
2615                 break;
2616         }
2617         if (oldlen != newlen) {
2618                 ASSERT(oldlen > newlen);
2619                 xfs_mod_fdblocks(ip->i_mount, (int64_t)(oldlen - newlen),
2620                                  false);
2621                 /*
2622                  * Nothing to do for disk quota accounting here.
2623                  */
2624                 xfs_mod_delalloc(ip->i_mount, (int64_t)newlen - oldlen);
2625         }
2626 }
2627
2628 /*
2629  * Convert a hole to a real allocation.
2630  */
2631 STATIC int                              /* error */
2632 xfs_bmap_add_extent_hole_real(
2633         struct xfs_trans        *tp,
2634         struct xfs_inode        *ip,
2635         int                     whichfork,
2636         struct xfs_iext_cursor  *icur,
2637         struct xfs_btree_cur    **curp,
2638         struct xfs_bmbt_irec    *new,
2639         int                     *logflagsp,
2640         uint32_t                flags)
2641 {
2642         struct xfs_ifork        *ifp = xfs_ifork_ptr(ip, whichfork);
2643         struct xfs_mount        *mp = ip->i_mount;
2644         struct xfs_btree_cur    *cur = *curp;
2645         int                     error;  /* error return value */
2646         int                     i;      /* temp state */
2647         xfs_bmbt_irec_t         left;   /* left neighbor extent entry */
2648         xfs_bmbt_irec_t         right;  /* right neighbor extent entry */
2649         int                     rval=0; /* return value (logging flags) */
2650         uint32_t                state = xfs_bmap_fork_to_state(whichfork);
2651         struct xfs_bmbt_irec    old;
2652
2653         ASSERT(!isnullstartblock(new->br_startblock));
2654         ASSERT(!cur || !(cur->bc_ino.flags & XFS_BTCUR_BMBT_WASDEL));
2655
2656         XFS_STATS_INC(mp, xs_add_exlist);
2657
2658         /*
2659          * Check and set flags if this segment has a left neighbor.
2660          */
2661         if (xfs_iext_peek_prev_extent(ifp, icur, &left)) {
2662                 state |= BMAP_LEFT_VALID;
2663                 if (isnullstartblock(left.br_startblock))
2664                         state |= BMAP_LEFT_DELAY;
2665         }
2666
2667         /*
2668          * Check and set flags if this segment has a current value.
2669          * Not true if we're inserting into the "hole" at eof.
2670          */
2671         if (xfs_iext_get_extent(ifp, icur, &right)) {
2672                 state |= BMAP_RIGHT_VALID;
2673                 if (isnullstartblock(right.br_startblock))
2674                         state |= BMAP_RIGHT_DELAY;
2675         }
2676
2677         /*
2678          * We're inserting a real allocation between "left" and "right".
2679          * Set the contiguity flags.  Don't let extents get too large.
2680          */
2681         if ((state & BMAP_LEFT_VALID) && !(state & BMAP_LEFT_DELAY) &&
2682             left.br_startoff + left.br_blockcount == new->br_startoff &&
2683             left.br_startblock + left.br_blockcount == new->br_startblock &&
2684             left.br_state == new->br_state &&
2685             left.br_blockcount + new->br_blockcount <= XFS_MAX_BMBT_EXTLEN)
2686                 state |= BMAP_LEFT_CONTIG;
2687
2688         if ((state & BMAP_RIGHT_VALID) && !(state & BMAP_RIGHT_DELAY) &&
2689             new->br_startoff + new->br_blockcount == right.br_startoff &&
2690             new->br_startblock + new->br_blockcount == right.br_startblock &&
2691             new->br_state == right.br_state &&
2692             new->br_blockcount + right.br_blockcount <= XFS_MAX_BMBT_EXTLEN &&
2693             (!(state & BMAP_LEFT_CONTIG) ||
2694              left.br_blockcount + new->br_blockcount +
2695              right.br_blockcount <= XFS_MAX_BMBT_EXTLEN))
2696                 state |= BMAP_RIGHT_CONTIG;
2697
2698         error = 0;
2699         /*
2700          * Select which case we're in here, and implement it.
2701          */
2702         switch (state & (BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG)) {
2703         case BMAP_LEFT_CONTIG | BMAP_RIGHT_CONTIG:
2704                 /*
2705                  * New allocation is contiguous with real allocations on the
2706                  * left and on the right.
2707                  * Merge all three into a single extent record.
2708                  */
2709                 left.br_blockcount += new->br_blockcount + right.br_blockcount;
2710
2711                 xfs_iext_remove(ip, icur, state);
2712                 xfs_iext_prev(ifp, icur);
2713                 xfs_iext_update_extent(ip, state, icur, &left);
2714                 ifp->if_nextents--;
2715
2716                 if (cur == NULL) {
2717                         rval = XFS_ILOG_CORE | xfs_ilog_fext(whichfork);
2718                 } else {
2719                         rval = XFS_ILOG_CORE;
2720                         error = xfs_bmbt_lookup_eq(cur, &right, &i);
2721                         if (error)
2722                                 goto done;
2723                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2724                                 error = -EFSCORRUPTED;
2725                                 goto done;
2726                         }
2727                         error = xfs_btree_delete(cur, &i);
2728                         if (error)
2729                                 goto done;
2730                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2731                                 error = -EFSCORRUPTED;
2732                                 goto done;
2733                         }
2734                         error = xfs_btree_decrement(cur, 0, &i);
2735                         if (error)
2736                                 goto done;
2737                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2738                                 error = -EFSCORRUPTED;
2739                                 goto done;
2740                         }
2741                         error = xfs_bmbt_update(cur, &left);
2742                         if (error)
2743                                 goto done;
2744                 }
2745                 break;
2746
2747         case BMAP_LEFT_CONTIG:
2748                 /*
2749                  * New allocation is contiguous with a real allocation
2750                  * on the left.
2751                  * Merge the new allocation with the left neighbor.
2752                  */
2753                 old = left;
2754                 left.br_blockcount += new->br_blockcount;
2755
2756                 xfs_iext_prev(ifp, icur);
2757                 xfs_iext_update_extent(ip, state, icur, &left);
2758
2759                 if (cur == NULL) {
2760                         rval = xfs_ilog_fext(whichfork);
2761                 } else {
2762                         rval = 0;
2763                         error = xfs_bmbt_lookup_eq(cur, &old, &i);
2764                         if (error)
2765                                 goto done;
2766                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2767                                 error = -EFSCORRUPTED;
2768                                 goto done;
2769                         }
2770                         error = xfs_bmbt_update(cur, &left);
2771                         if (error)
2772                                 goto done;
2773                 }
2774                 break;
2775
2776         case BMAP_RIGHT_CONTIG:
2777                 /*
2778                  * New allocation is contiguous with a real allocation
2779                  * on the right.
2780                  * Merge the new allocation with the right neighbor.
2781                  */
2782                 old = right;
2783
2784                 right.br_startoff = new->br_startoff;
2785                 right.br_startblock = new->br_startblock;
2786                 right.br_blockcount += new->br_blockcount;
2787                 xfs_iext_update_extent(ip, state, icur, &right);
2788
2789                 if (cur == NULL) {
2790                         rval = xfs_ilog_fext(whichfork);
2791                 } else {
2792                         rval = 0;
2793                         error = xfs_bmbt_lookup_eq(cur, &old, &i);
2794                         if (error)
2795                                 goto done;
2796                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2797                                 error = -EFSCORRUPTED;
2798                                 goto done;
2799                         }
2800                         error = xfs_bmbt_update(cur, &right);
2801                         if (error)
2802                                 goto done;
2803                 }
2804                 break;
2805
2806         case 0:
2807                 /*
2808                  * New allocation is not contiguous with another
2809                  * real allocation.
2810                  * Insert a new entry.
2811                  */
2812                 xfs_iext_insert(ip, icur, new, state);
2813                 ifp->if_nextents++;
2814
2815                 if (cur == NULL) {
2816                         rval = XFS_ILOG_CORE | xfs_ilog_fext(whichfork);
2817                 } else {
2818                         rval = XFS_ILOG_CORE;
2819                         error = xfs_bmbt_lookup_eq(cur, new, &i);
2820                         if (error)
2821                                 goto done;
2822                         if (XFS_IS_CORRUPT(mp, i != 0)) {
2823                                 error = -EFSCORRUPTED;
2824                                 goto done;
2825                         }
2826                         error = xfs_btree_insert(cur, &i);
2827                         if (error)
2828                                 goto done;
2829                         if (XFS_IS_CORRUPT(mp, i != 1)) {
2830                                 error = -EFSCORRUPTED;
2831                                 goto done;
2832                         }
2833                 }
2834                 break;
2835         }
2836
2837         /* add reverse mapping unless caller opted out */
2838         if (!(flags & XFS_BMAPI_NORMAP))
2839                 xfs_rmap_map_extent(tp, ip, whichfork, new);
2840
2841         /* convert to a btree if necessary */
2842         if (xfs_bmap_needs_btree(ip, whichfork)) {
2843                 int     tmp_logflags;   /* partial log flag return val */
2844
2845                 ASSERT(cur == NULL);
2846                 error = xfs_bmap_extents_to_btree(tp, ip, curp, 0,
2847                                 &tmp_logflags, whichfork);
2848                 *logflagsp |= tmp_logflags;
2849                 cur = *curp;
2850                 if (error)
2851                         goto done;
2852         }
2853
2854         /* clear out the allocated field, done with it now in any case. */
2855         if (cur)
2856                 cur->bc_ino.allocated = 0;
2857
2858         xfs_bmap_check_leaf_extents(cur, ip, whichfork);
2859 done:
2860         *logflagsp |= rval;
2861         return error;
2862 }
2863
2864 /*
2865  * Functions used in the extent read, allocate and remove paths
2866  */
2867
2868 /*
2869  * Adjust the size of the new extent based on i_extsize and rt extsize.
2870  */
2871 int
2872 xfs_bmap_extsize_align(
2873         xfs_mount_t     *mp,
2874         xfs_bmbt_irec_t *gotp,          /* next extent pointer */
2875         xfs_bmbt_irec_t *prevp,         /* previous extent pointer */
2876         xfs_extlen_t    extsz,          /* align to this extent size */
2877         int             rt,             /* is this a realtime inode? */
2878         int             eof,            /* is extent at end-of-file? */
2879         int             delay,          /* creating delalloc extent? */
2880         int             convert,        /* overwriting unwritten extent? */
2881         xfs_fileoff_t   *offp,          /* in/out: aligned offset */
2882         xfs_extlen_t    *lenp)          /* in/out: aligned length */
2883 {
2884         xfs_fileoff_t   orig_off;       /* original offset */
2885         xfs_extlen_t    orig_alen;      /* original length */
2886         xfs_fileoff_t   orig_end;       /* original off+len */
2887         xfs_fileoff_t   nexto;          /* next file offset */
2888         xfs_fileoff_t   prevo;          /* previous file offset */
2889         xfs_fileoff_t   align_off;      /* temp for offset */
2890         xfs_extlen_t    align_alen;     /* temp for length */
2891         xfs_extlen_t    temp;           /* temp for calculations */
2892
2893         if (convert)
2894                 return 0;
2895
2896         orig_off = align_off = *offp;
2897         orig_alen = align_alen = *lenp;
2898         orig_end = orig_off + orig_alen;
2899
2900         /*
2901          * If this request overlaps an existing extent, then don't
2902          * attempt to perform any additional alignment.
2903          */
2904         if (!delay && !eof &&
2905             (orig_off >= gotp->br_startoff) &&
2906             (orig_end <= gotp->br_startoff + gotp->br_blockcount)) {
2907                 return 0;
2908         }
2909
2910         /*
2911          * If the file offset is unaligned vs. the extent size
2912          * we need to align it.  This will be possible unless
2913          * the file was previously written with a kernel that didn't
2914          * perform this alignment, or if a truncate shot us in the
2915          * foot.
2916          */
2917         div_u64_rem(orig_off, extsz, &temp);
2918         if (temp) {
2919                 align_alen += temp;
2920                 align_off -= temp;
2921         }
2922
2923         /* Same adjustment for the end of the requested area. */
2924         temp = (align_alen % extsz);
2925         if (temp)
2926                 align_alen += extsz - temp;
2927
2928         /*
2929          * For large extent hint sizes, the aligned extent might be larger than
2930          * XFS_BMBT_MAX_EXTLEN. In that case, reduce the size by an extsz so
2931          * that it pulls the length back under XFS_BMBT_MAX_EXTLEN. The outer
2932          * allocation loops handle short allocation just fine, so it is safe to
2933          * do this. We only want to do it when we are forced to, though, because
2934          * it means more allocation operations are required.
2935          */
2936         while (align_alen > XFS_MAX_BMBT_EXTLEN)
2937                 align_alen -= extsz;
2938         ASSERT(align_alen <= XFS_MAX_BMBT_EXTLEN);
2939
2940         /*
2941          * If the previous block overlaps with this proposed allocation
2942          * then move the start forward without adjusting the length.
2943          */
2944         if (prevp->br_startoff != NULLFILEOFF) {
2945                 if (prevp->br_startblock == HOLESTARTBLOCK)
2946                         prevo = prevp->br_startoff;
2947                 else
2948                         prevo = prevp->br_startoff + prevp->br_blockcount;
2949         } else
2950                 prevo = 0;
2951         if (align_off != orig_off && align_off < prevo)
2952                 align_off = prevo;
2953         /*
2954          * If the next block overlaps with this proposed allocation
2955          * then move the start back without adjusting the length,
2956          * but not before offset 0.
2957          * This may of course make the start overlap previous block,
2958          * and if we hit the offset 0 limit then the next block
2959          * can still overlap too.
2960          */
2961         if (!eof && gotp->br_startoff != NULLFILEOFF) {
2962                 if ((delay && gotp->br_startblock == HOLESTARTBLOCK) ||
2963                     (!delay && gotp->br_startblock == DELAYSTARTBLOCK))
2964                         nexto = gotp->br_startoff + gotp->br_blockcount;
2965                 else
2966                         nexto = gotp->br_startoff;
2967         } else
2968                 nexto = NULLFILEOFF;
2969         if (!eof &&
2970             align_off + align_alen != orig_end &&
2971             align_off + align_alen > nexto)
2972                 align_off = nexto > align_alen ? nexto - align_alen : 0;
2973         /*
2974          * If we're now overlapping the next or previous extent that
2975          * means we can't fit an extsz piece in this hole.  Just move
2976          * the start forward to the first valid spot and set
2977          * the length so we hit the end.
2978          */
2979         if (align_off != orig_off && align_off < prevo)
2980                 align_off = prevo;
2981         if (align_off + align_alen != orig_end &&
2982             align_off + align_alen > nexto &&
2983             nexto != NULLFILEOFF) {
2984                 ASSERT(nexto > prevo);
2985                 align_alen = nexto - align_off;
2986         }
2987
2988         /*
2989          * If realtime, and the result isn't a multiple of the realtime
2990          * extent size we need to remove blocks until it is.
2991          */
2992         if (rt && (temp = (align_alen % mp->m_sb.sb_rextsize))) {
2993                 /*
2994                  * We're not covering the original request, or
2995                  * we won't be able to once we fix the length.
2996                  */
2997                 if (orig_off < align_off ||
2998                     orig_end > align_off + align_alen ||
2999                     align_alen - temp < orig_alen)
3000                         return -EINVAL;
3001                 /*
3002                  * Try to fix it by moving the start up.
3003                  */
3004                 if (align_off + temp <= orig_off) {
3005                         align_alen -= temp;
3006                         align_off += temp;
3007                 }
3008                 /*
3009                  * Try to fix it by moving the end in.
3010                  */
3011                 else if (align_off + align_alen - temp >= orig_end)
3012                         align_alen -= temp;
3013                 /*
3014                  * Set the start to the minimum then trim the length.
3015                  */
3016                 else {
3017                         align_alen -= orig_off - align_off;
3018                         align_off = orig_off;
3019                         align_alen -= align_alen % mp->m_sb.sb_rextsize;
3020                 }
3021                 /*
3022                  * Result doesn't cover the request, fail it.
3023                  */
3024                 if (orig_off < align_off || orig_end > align_off + align_alen)
3025                         return -EINVAL;
3026         } else {
3027                 ASSERT(orig_off >= align_off);
3028                 /* see XFS_BMBT_MAX_EXTLEN handling above */
3029                 ASSERT(orig_end <= align_off + align_alen ||
3030                        align_alen + extsz > XFS_MAX_BMBT_EXTLEN);
3031         }
3032
3033 #ifdef DEBUG
3034         if (!eof && gotp->br_startoff != NULLFILEOFF)
3035                 ASSERT(align_off + align_alen <= gotp->br_startoff);
3036         if (prevp->br_startoff != NULLFILEOFF)
3037                 ASSERT(align_off >= prevp->br_startoff + prevp->br_blockcount);
3038 #endif
3039
3040         *lenp = align_alen;
3041         *offp = align_off;
3042         return 0;
3043 }
3044
3045 #define XFS_ALLOC_GAP_UNITS     4
3046
3047 void
3048 xfs_bmap_adjacent(
3049         struct xfs_bmalloca     *ap)    /* bmap alloc argument struct */
3050 {
3051         xfs_fsblock_t   adjust;         /* adjustment to block numbers */
3052         xfs_mount_t     *mp;            /* mount point structure */
3053         int             rt;             /* true if inode is realtime */
3054
3055 #define ISVALID(x,y)    \
3056         (rt ? \
3057                 (x) < mp->m_sb.sb_rblocks : \
3058                 XFS_FSB_TO_AGNO(mp, x) == XFS_FSB_TO_AGNO(mp, y) && \
3059                 XFS_FSB_TO_AGNO(mp, x) < mp->m_sb.sb_agcount && \
3060                 XFS_FSB_TO_AGBNO(mp, x) < mp->m_sb.sb_agblocks)
3061
3062         mp = ap->ip->i_mount;
3063         rt = XFS_IS_REALTIME_INODE(ap->ip) &&
3064                 (ap->datatype & XFS_ALLOC_USERDATA);
3065         /*
3066          * If allocating at eof, and there's a previous real block,
3067          * try to use its last block as our starting point.
3068          */
3069         if (ap->eof && ap->prev.br_startoff != NULLFILEOFF &&
3070             !isnullstartblock(ap->prev.br_startblock) &&
3071             ISVALID(ap->prev.br_startblock + ap->prev.br_blockcount,
3072                     ap->prev.br_startblock)) {
3073                 ap->blkno = ap->prev.br_startblock + ap->prev.br_blockcount;
3074                 /*
3075                  * Adjust for the gap between prevp and us.
3076                  */
3077                 adjust = ap->offset -
3078                         (ap->prev.br_startoff + ap->prev.br_blockcount);
3079                 if (adjust &&
3080                     ISVALID(ap->blkno + adjust, ap->prev.br_startblock))
3081                         ap->blkno += adjust;
3082         }
3083         /*
3084          * If not at eof, then compare the two neighbor blocks.
3085          * Figure out whether either one gives us a good starting point,
3086          * and pick the better one.
3087          */
3088         else if (!ap->eof) {
3089                 xfs_fsblock_t   gotbno;         /* right side block number */
3090                 xfs_fsblock_t   gotdiff=0;      /* right side difference */
3091                 xfs_fsblock_t   prevbno;        /* left side block number */
3092                 xfs_fsblock_t   prevdiff=0;     /* left side difference */
3093
3094                 /*
3095                  * If there's a previous (left) block, select a requested
3096                  * start block based on it.
3097                  */
3098                 if (ap->prev.br_startoff != NULLFILEOFF &&
3099                     !isnullstartblock(ap->prev.br_startblock) &&
3100                     (prevbno = ap->prev.br_startblock +
3101                                ap->prev.br_blockcount) &&
3102                     ISVALID(prevbno, ap->prev.br_startblock)) {
3103                         /*
3104                          * Calculate gap to end of previous block.
3105                          */
3106                         adjust = prevdiff = ap->offset -
3107                                 (ap->prev.br_startoff +
3108                                  ap->prev.br_blockcount);
3109                         /*
3110                          * Figure the startblock based on the previous block's
3111                          * end and the gap size.
3112                          * Heuristic!
3113                          * If the gap is large relative to the piece we're
3114                          * allocating, or using it gives us an invalid block
3115                          * number, then just use the end of the previous block.
3116                          */
3117                         if (prevdiff <= XFS_ALLOC_GAP_UNITS * ap->length &&
3118                             ISVALID(prevbno + prevdiff,
3119                                     ap->prev.br_startblock))
3120                                 prevbno += adjust;
3121                         else
3122                                 prevdiff += adjust;
3123                 }
3124                 /*
3125                  * No previous block or can't follow it, just default.
3126                  */
3127                 else
3128                         prevbno = NULLFSBLOCK;
3129                 /*
3130                  * If there's a following (right) block, select a requested
3131                  * start block based on it.
3132                  */
3133                 if (!isnullstartblock(ap->got.br_startblock)) {
3134                         /*
3135                          * Calculate gap to start of next block.
3136                          */
3137                         adjust = gotdiff = ap->got.br_startoff - ap->offset;
3138                         /*
3139                          * Figure the startblock based on the next block's
3140                          * start and the gap size.
3141                          */
3142                         gotbno = ap->got.br_startblock;
3143                         /*
3144                          * Heuristic!
3145                          * If the gap is large relative to the piece we're
3146                          * allocating, or using it gives us an invalid block
3147                          * number, then just use the start of the next block
3148                          * offset by our length.
3149                          */
3150                         if (gotdiff <= XFS_ALLOC_GAP_UNITS * ap->length &&
3151                             ISVALID(gotbno - gotdiff, gotbno))
3152                                 gotbno -= adjust;
3153                         else if (ISVALID(gotbno - ap->length, gotbno)) {
3154                                 gotbno -= ap->length;
3155                                 gotdiff += adjust - ap->length;
3156                         } else
3157                                 gotdiff += adjust;
3158                 }
3159                 /*
3160                  * No next block, just default.
3161                  */
3162                 else
3163                         gotbno = NULLFSBLOCK;
3164                 /*
3165                  * If both valid, pick the better one, else the only good
3166                  * one, else ap->blkno is already set (to 0 or the inode block).
3167                  */
3168                 if (prevbno != NULLFSBLOCK && gotbno != NULLFSBLOCK)
3169                         ap->blkno = prevdiff <= gotdiff ? prevbno : gotbno;
3170                 else if (prevbno != NULLFSBLOCK)
3171                         ap->blkno = prevbno;
3172                 else if (gotbno != NULLFSBLOCK)
3173                         ap->blkno = gotbno;
3174         }
3175 #undef ISVALID
3176 }
3177
3178 int
3179 xfs_bmap_longest_free_extent(
3180         struct xfs_perag        *pag,
3181         struct xfs_trans        *tp,
3182         xfs_extlen_t            *blen)
3183 {
3184         xfs_extlen_t            longest;
3185         int                     error = 0;
3186
3187         if (!xfs_perag_initialised_agf(pag)) {
3188                 error = xfs_alloc_read_agf(pag, tp, XFS_ALLOC_FLAG_TRYLOCK,
3189                                 NULL);
3190                 if (error)
3191                         return error;
3192         }
3193
3194         longest = xfs_alloc_longest_free_extent(pag,
3195                                 xfs_alloc_min_freelist(pag->pag_mount, pag),
3196                                 xfs_ag_resv_needed(pag, XFS_AG_RESV_NONE));
3197         if (*blen < longest)
3198                 *blen = longest;
3199
3200         return 0;
3201 }
3202
3203 static xfs_extlen_t
3204 xfs_bmap_select_minlen(
3205         struct xfs_bmalloca     *ap,
3206         struct xfs_alloc_arg    *args,
3207         xfs_extlen_t            blen)
3208 {
3209
3210         /*
3211          * Since we used XFS_ALLOC_FLAG_TRYLOCK in _longest_free_extent(), it is
3212          * possible that there is enough contiguous free space for this request.
3213          */
3214         if (blen < ap->minlen)
3215                 return ap->minlen;
3216
3217         /*
3218          * If the best seen length is less than the request length,
3219          * use the best as the minimum, otherwise we've got the maxlen we
3220          * were asked for.
3221          */
3222         if (blen < args->maxlen)
3223                 return blen;
3224         return args->maxlen;
3225 }
3226
3227 static int
3228 xfs_bmap_btalloc_select_lengths(
3229         struct xfs_bmalloca     *ap,
3230         struct xfs_alloc_arg    *args,
3231         xfs_extlen_t            *blen)
3232 {
3233         struct xfs_mount        *mp = args->mp;
3234         struct xfs_perag        *pag;
3235         xfs_agnumber_t          agno, startag;
3236         int                     error = 0;
3237
3238         if (ap->tp->t_flags & XFS_TRANS_LOWMODE) {
3239                 args->total = ap->minlen;
3240                 args->minlen = ap->minlen;
3241                 return 0;
3242         }
3243
3244         args->total = ap->total;
3245         startag = XFS_FSB_TO_AGNO(mp, ap->blkno);
3246         if (startag == NULLAGNUMBER)
3247                 startag = 0;
3248
3249         *blen = 0;
3250         for_each_perag_wrap(mp, startag, agno, pag) {
3251                 error = xfs_bmap_longest_free_extent(pag, args->tp, blen);
3252                 if (error && error != -EAGAIN)
3253                         break;
3254                 error = 0;
3255                 if (*blen >= args->maxlen)
3256                         break;
3257         }
3258         if (pag)
3259                 xfs_perag_rele(pag);
3260
3261         args->minlen = xfs_bmap_select_minlen(ap, args, *blen);
3262         return error;
3263 }
3264
3265 /* Update all inode and quota accounting for the allocation we just did. */
3266 static void
3267 xfs_bmap_btalloc_accounting(
3268         struct xfs_bmalloca     *ap,
3269         struct xfs_alloc_arg    *args)
3270 {
3271         if (ap->flags & XFS_BMAPI_COWFORK) {
3272                 /*
3273                  * COW fork blocks are in-core only and thus are treated as
3274                  * in-core quota reservation (like delalloc blocks) even when
3275                  * converted to real blocks. The quota reservation is not
3276                  * accounted to disk until blocks are remapped to the data
3277                  * fork. So if these blocks were previously delalloc, we
3278                  * already have quota reservation and there's nothing to do
3279                  * yet.
3280                  */
3281                 if (ap->wasdel) {
3282                         xfs_mod_delalloc(ap->ip->i_mount, -(int64_t)args->len);
3283                         return;
3284                 }
3285
3286                 /*
3287                  * Otherwise, we've allocated blocks in a hole. The transaction
3288                  * has acquired in-core quota reservation for this extent.
3289                  * Rather than account these as real blocks, however, we reduce
3290                  * the transaction quota reservation based on the allocation.
3291                  * This essentially transfers the transaction quota reservation
3292                  * to that of a delalloc extent.
3293                  */
3294                 ap->ip->i_delayed_blks += args->len;
3295                 xfs_trans_mod_dquot_byino(ap->tp, ap->ip, XFS_TRANS_DQ_RES_BLKS,
3296                                 -(long)args->len);
3297                 return;
3298         }
3299
3300         /* data/attr fork only */
3301         ap->ip->i_nblocks += args->len;
3302         xfs_trans_log_inode(ap->tp, ap->ip, XFS_ILOG_CORE);
3303         if (ap->wasdel) {
3304                 ap->ip->i_delayed_blks -= args->len;
3305                 xfs_mod_delalloc(ap->ip->i_mount, -(int64_t)args->len);
3306         }
3307         xfs_trans_mod_dquot_byino(ap->tp, ap->ip,
3308                 ap->wasdel ? XFS_TRANS_DQ_DELBCOUNT : XFS_TRANS_DQ_BCOUNT,
3309                 args->len);
3310 }
3311
3312 static int
3313 xfs_bmap_compute_alignments(
3314         struct xfs_bmalloca     *ap,
3315         struct xfs_alloc_arg    *args)
3316 {
3317         struct xfs_mount        *mp = args->mp;
3318         xfs_extlen_t            align = 0; /* minimum allocation alignment */
3319         int                     stripe_align = 0;
3320
3321         /* stripe alignment for allocation is determined by mount parameters */
3322         if (mp->m_swidth && xfs_has_swalloc(mp))
3323                 stripe_align = mp->m_swidth;
3324         else if (mp->m_dalign)
3325                 stripe_align = mp->m_dalign;
3326
3327         if (ap->flags & XFS_BMAPI_COWFORK)
3328                 align = xfs_get_cowextsz_hint(ap->ip);
3329         else if (ap->datatype & XFS_ALLOC_USERDATA)
3330                 align = xfs_get_extsz_hint(ap->ip);
3331         if (align) {
3332                 if (xfs_bmap_extsize_align(mp, &ap->got, &ap->prev, align, 0,
3333                                         ap->eof, 0, ap->conv, &ap->offset,
3334                                         &ap->length))
3335                         ASSERT(0);
3336                 ASSERT(ap->length);
3337         }
3338
3339         /* apply extent size hints if obtained earlier */
3340         if (align) {
3341                 args->prod = align;
3342                 div_u64_rem(ap->offset, args->prod, &args->mod);
3343                 if (args->mod)
3344                         args->mod = args->prod - args->mod;
3345         } else if (mp->m_sb.sb_blocksize >= PAGE_SIZE) {
3346                 args->prod = 1;
3347                 args->mod = 0;
3348         } else {
3349                 args->prod = PAGE_SIZE >> mp->m_sb.sb_blocklog;
3350                 div_u64_rem(ap->offset, args->prod, &args->mod);
3351                 if (args->mod)
3352                         args->mod = args->prod - args->mod;
3353         }
3354
3355         return stripe_align;
3356 }
3357
3358 static void
3359 xfs_bmap_process_allocated_extent(
3360         struct xfs_bmalloca     *ap,
3361         struct xfs_alloc_arg    *args,
3362         xfs_fileoff_t           orig_offset,
3363         xfs_extlen_t            orig_length)
3364 {
3365         ap->blkno = args->fsbno;
3366         ap->length = args->len;
3367         /*
3368          * If the extent size hint is active, we tried to round the
3369          * caller's allocation request offset down to extsz and the
3370          * length up to another extsz boundary.  If we found a free
3371          * extent we mapped it in starting at this new offset.  If the
3372          * newly mapped space isn't long enough to cover any of the
3373          * range of offsets that was originally requested, move the
3374          * mapping up so that we can fill as much of the caller's
3375          * original request as possible.  Free space is apparently
3376          * very fragmented so we're unlikely to be able to satisfy the
3377          * hints anyway.
3378          */
3379         if (ap->length <= orig_length)
3380                 ap->offset = orig_offset;
3381         else if (ap->offset + ap->length < orig_offset + orig_length)
3382                 ap->offset = orig_offset + orig_length - ap->length;
3383         xfs_bmap_btalloc_accounting(ap, args);
3384 }
3385
3386 #ifdef DEBUG
3387 static int
3388 xfs_bmap_exact_minlen_extent_alloc(
3389         struct xfs_bmalloca     *ap)
3390 {
3391         struct xfs_mount        *mp = ap->ip->i_mount;
3392         struct xfs_alloc_arg    args = { .tp = ap->tp, .mp = mp };
3393         xfs_fileoff_t           orig_offset;
3394         xfs_extlen_t            orig_length;
3395         int                     error;
3396
3397         ASSERT(ap->length);
3398
3399         if (ap->minlen != 1) {
3400                 ap->blkno = NULLFSBLOCK;
3401                 ap->length = 0;
3402                 return 0;
3403         }
3404
3405         orig_offset = ap->offset;
3406         orig_length = ap->length;
3407
3408         args.alloc_minlen_only = 1;
3409
3410         xfs_bmap_compute_alignments(ap, &args);
3411
3412         /*
3413          * Unlike the longest extent available in an AG, we don't track
3414          * the length of an AG's shortest extent.
3415          * XFS_ERRTAG_BMAP_ALLOC_MINLEN_EXTENT is a debug only knob and
3416          * hence we can afford to start traversing from the 0th AG since
3417          * we need not be concerned about a drop in performance in
3418          * "debug only" code paths.
3419          */
3420         ap->blkno = XFS_AGB_TO_FSB(mp, 0, 0);
3421
3422         args.oinfo = XFS_RMAP_OINFO_SKIP_UPDATE;
3423         args.minlen = args.maxlen = ap->minlen;
3424         args.total = ap->total;
3425
3426         args.alignment = 1;
3427         args.minalignslop = 0;
3428
3429         args.minleft = ap->minleft;
3430         args.wasdel = ap->wasdel;
3431         args.resv = XFS_AG_RESV_NONE;
3432         args.datatype = ap->datatype;
3433
3434         error = xfs_alloc_vextent_first_ag(&args, ap->blkno);
3435         if (error)
3436                 return error;
3437
3438         if (args.fsbno != NULLFSBLOCK) {
3439                 xfs_bmap_process_allocated_extent(ap, &args, orig_offset,
3440                         orig_length);
3441         } else {
3442                 ap->blkno = NULLFSBLOCK;
3443                 ap->length = 0;
3444         }
3445
3446         return 0;
3447 }
3448 #else
3449
3450 #define xfs_bmap_exact_minlen_extent_alloc(bma) (-EFSCORRUPTED)
3451
3452 #endif
3453
3454 /*
3455  * If we are not low on available data blocks and we are allocating at
3456  * EOF, optimise allocation for contiguous file extension and/or stripe
3457  * alignment of the new extent.
3458  *
3459  * NOTE: ap->aeof is only set if the allocation length is >= the
3460  * stripe unit and the allocation offset is at the end of file.
3461  */
3462 static int
3463 xfs_bmap_btalloc_at_eof(
3464         struct xfs_bmalloca     *ap,
3465         struct xfs_alloc_arg    *args,
3466         xfs_extlen_t            blen,
3467         int                     stripe_align,
3468         bool                    ag_only)
3469 {
3470         struct xfs_mount        *mp = args->mp;
3471         struct xfs_perag        *caller_pag = args->pag;
3472         int                     error;
3473
3474         /*
3475          * If there are already extents in the file, try an exact EOF block
3476          * allocation to extend the file as a contiguous extent. If that fails,
3477          * or it's the first allocation in a file, just try for a stripe aligned
3478          * allocation.
3479          */
3480         if (ap->offset) {
3481                 xfs_extlen_t    nextminlen = 0;
3482
3483                 /*
3484                  * Compute the minlen+alignment for the next case.  Set slop so
3485                  * that the value of minlen+alignment+slop doesn't go up between
3486                  * the calls.
3487                  */
3488                 args->alignment = 1;
3489                 if (blen > stripe_align && blen <= args->maxlen)
3490                         nextminlen = blen - stripe_align;
3491                 else
3492                         nextminlen = args->minlen;
3493                 if (nextminlen + stripe_align > args->minlen + 1)
3494                         args->minalignslop = nextminlen + stripe_align -
3495                                         args->minlen - 1;
3496                 else
3497                         args->minalignslop = 0;
3498
3499                 if (!caller_pag)
3500                         args->pag = xfs_perag_get(mp, XFS_FSB_TO_AGNO(mp, ap->blkno));
3501                 error = xfs_alloc_vextent_exact_bno(args, ap->blkno);
3502                 if (!caller_pag) {
3503                         xfs_perag_put(args->pag);
3504                         args->pag = NULL;
3505                 }
3506                 if (error)
3507                         return error;
3508
3509                 if (args->fsbno != NULLFSBLOCK)
3510                         return 0;
3511                 /*
3512                  * Exact allocation failed. Reset to try an aligned allocation
3513                  * according to the original allocation specification.
3514                  */
3515                 args->alignment = stripe_align;
3516                 args->minlen = nextminlen;
3517                 args->minalignslop = 0;
3518         } else {
3519                 /*
3520                  * Adjust minlen to try and preserve alignment if we
3521                  * can't guarantee an aligned maxlen extent.
3522                  */
3523                 args->alignment = stripe_align;
3524                 if (blen > args->alignment &&
3525                     blen <= args->maxlen + args->alignment)
3526                         args->minlen = blen - args->alignment;
3527                 args->minalignslop = 0;
3528         }
3529
3530         if (ag_only) {
3531                 error = xfs_alloc_vextent_near_bno(args, ap->blkno);
3532         } else {
3533                 args->pag = NULL;
3534                 error = xfs_alloc_vextent_start_ag(args, ap->blkno);
3535                 ASSERT(args->pag == NULL);
3536                 args->pag = caller_pag;
3537         }
3538         if (error)
3539                 return error;
3540
3541         if (args->fsbno != NULLFSBLOCK)
3542                 return 0;
3543
3544         /*
3545          * Allocation failed, so turn return the allocation args to their
3546          * original non-aligned state so the caller can proceed on allocation
3547          * failure as if this function was never called.
3548          */
3549         args->alignment = 1;
3550         return 0;
3551 }
3552
3553 /*
3554  * We have failed multiple allocation attempts so now are in a low space
3555  * allocation situation. Try a locality first full filesystem minimum length
3556  * allocation whilst still maintaining necessary total block reservation
3557  * requirements.
3558  *
3559  * If that fails, we are now critically low on space, so perform a last resort
3560  * allocation attempt: no reserve, no locality, blocking, minimum length, full
3561  * filesystem free space scan. We also indicate to future allocations in this
3562  * transaction that we are critically low on space so they don't waste time on
3563  * allocation modes that are unlikely to succeed.
3564  */
3565 int
3566 xfs_bmap_btalloc_low_space(
3567         struct xfs_bmalloca     *ap,
3568         struct xfs_alloc_arg    *args)
3569 {
3570         int                     error;
3571
3572         if (args->minlen > ap->minlen) {
3573                 args->minlen = ap->minlen;
3574                 error = xfs_alloc_vextent_start_ag(args, ap->blkno);
3575                 if (error || args->fsbno != NULLFSBLOCK)
3576                         return error;
3577         }
3578
3579         /* Last ditch attempt before failure is declared. */
3580         args->total = ap->minlen;
3581         error = xfs_alloc_vextent_first_ag(args, 0);
3582         if (error)
3583                 return error;
3584         ap->tp->t_flags |= XFS_TRANS_LOWMODE;
3585         return 0;
3586 }
3587
3588 static int
3589 xfs_bmap_btalloc_filestreams(
3590         struct xfs_bmalloca     *ap,
3591         struct xfs_alloc_arg    *args,
3592         int                     stripe_align)
3593 {
3594         xfs_extlen_t            blen = 0;
3595         int                     error = 0;
3596
3597
3598         error = xfs_filestream_select_ag(ap, args, &blen);
3599         if (error)
3600                 return error;
3601         ASSERT(args->pag);
3602
3603         /*
3604          * If we are in low space mode, then optimal allocation will fail so
3605          * prepare for minimal allocation and jump to the low space algorithm
3606          * immediately.
3607          */
3608         if (ap->tp->t_flags & XFS_TRANS_LOWMODE) {
3609                 args->minlen = ap->minlen;
3610                 ASSERT(args->fsbno == NULLFSBLOCK);
3611                 goto out_low_space;
3612         }
3613
3614         args->minlen = xfs_bmap_select_minlen(ap, args, blen);
3615         if (ap->aeof)
3616                 error = xfs_bmap_btalloc_at_eof(ap, args, blen, stripe_align,
3617                                 true);
3618
3619         if (!error && args->fsbno == NULLFSBLOCK)
3620                 error = xfs_alloc_vextent_near_bno(args, ap->blkno);
3621
3622 out_low_space:
3623         /*
3624          * We are now done with the perag reference for the filestreams
3625          * association provided by xfs_filestream_select_ag(). Release it now as
3626          * we've either succeeded, had a fatal error or we are out of space and
3627          * need to do a full filesystem scan for free space which will take it's
3628          * own references.
3629          */
3630         xfs_perag_rele(args->pag);
3631         args->pag = NULL;
3632         if (error || args->fsbno != NULLFSBLOCK)
3633                 return error;
3634
3635         return xfs_bmap_btalloc_low_space(ap, args);
3636 }
3637
3638 static int
3639 xfs_bmap_btalloc_best_length(
3640         struct xfs_bmalloca     *ap,
3641         struct xfs_alloc_arg    *args,
3642         int                     stripe_align)
3643 {
3644         xfs_extlen_t            blen = 0;
3645         int                     error;
3646
3647         ap->blkno = XFS_INO_TO_FSB(args->mp, ap->ip->i_ino);
3648         xfs_bmap_adjacent(ap);
3649
3650         /*
3651          * Search for an allocation group with a single extent large enough for
3652          * the request.  If one isn't found, then adjust the minimum allocation
3653          * size to the largest space found.
3654          */
3655         error = xfs_bmap_btalloc_select_lengths(ap, args, &blen);
3656         if (error)
3657                 return error;
3658
3659         /*
3660          * Don't attempt optimal EOF allocation if previous allocations barely
3661          * succeeded due to being near ENOSPC. It is highly unlikely we'll get
3662          * optimal or even aligned allocations in this case, so don't waste time
3663          * trying.
3664          */
3665         if (ap->aeof && !(ap->tp->t_flags & XFS_TRANS_LOWMODE)) {
3666                 error = xfs_bmap_btalloc_at_eof(ap, args, blen, stripe_align,
3667                                 false);
3668                 if (error || args->fsbno != NULLFSBLOCK)
3669                         return error;
3670         }
3671
3672         error = xfs_alloc_vextent_start_ag(args, ap->blkno);
3673         if (error || args->fsbno != NULLFSBLOCK)
3674                 return error;
3675
3676         return xfs_bmap_btalloc_low_space(ap, args);
3677 }
3678
3679 static int
3680 xfs_bmap_btalloc(
3681         struct xfs_bmalloca     *ap)
3682 {
3683         struct xfs_mount        *mp = ap->ip->i_mount;
3684         struct xfs_alloc_arg    args = {
3685                 .tp             = ap->tp,
3686                 .mp             = mp,
3687                 .fsbno          = NULLFSBLOCK,
3688                 .oinfo          = XFS_RMAP_OINFO_SKIP_UPDATE,
3689                 .minleft        = ap->minleft,
3690                 .wasdel         = ap->wasdel,
3691                 .resv           = XFS_AG_RESV_NONE,
3692                 .datatype       = ap->datatype,
3693                 .alignment      = 1,
3694                 .minalignslop   = 0,
3695         };
3696         xfs_fileoff_t           orig_offset;
3697         xfs_extlen_t            orig_length;
3698         int                     error;
3699         int                     stripe_align;
3700
3701         ASSERT(ap->length);
3702         orig_offset = ap->offset;
3703         orig_length = ap->length;
3704
3705         stripe_align = xfs_bmap_compute_alignments(ap, &args);
3706
3707         /* Trim the allocation back to the maximum an AG can fit. */
3708         args.maxlen = min(ap->length, mp->m_ag_max_usable);
3709
3710         if ((ap->datatype & XFS_ALLOC_USERDATA) &&
3711             xfs_inode_is_filestream(ap->ip))
3712                 error = xfs_bmap_btalloc_filestreams(ap, &args, stripe_align);
3713         else
3714                 error = xfs_bmap_btalloc_best_length(ap, &args, stripe_align);
3715         if (error)
3716                 return error;
3717
3718         if (args.fsbno != NULLFSBLOCK) {
3719                 xfs_bmap_process_allocated_extent(ap, &args, orig_offset,
3720                         orig_length);
3721         } else {
3722                 ap->blkno = NULLFSBLOCK;
3723                 ap->length = 0;
3724         }
3725         return 0;
3726 }
3727
3728 /* Trim extent to fit a logical block range. */
3729 void
3730 xfs_trim_extent(
3731         struct xfs_bmbt_irec    *irec,
3732         xfs_fileoff_t           bno,
3733         xfs_filblks_t           len)
3734 {
3735         xfs_fileoff_t           distance;
3736         xfs_fileoff_t           end = bno + len;
3737
3738         if (irec->br_startoff + irec->br_blockcount <= bno ||
3739             irec->br_startoff >= end) {
3740                 irec->br_blockcount = 0;
3741                 return;
3742         }
3743
3744         if (irec->br_startoff < bno) {
3745                 distance = bno - irec->br_startoff;
3746                 if (isnullstartblock(irec->br_startblock))
3747                         irec->br_startblock = DELAYSTARTBLOCK;
3748                 if (irec->br_startblock != DELAYSTARTBLOCK &&
3749                     irec->br_startblock != HOLESTARTBLOCK)
3750                         irec->br_startblock += distance;
3751                 irec->br_startoff += distance;
3752                 irec->br_blockcount -= distance;
3753         }
3754
3755         if (end < irec->br_startoff + irec->br_blockcount) {
3756                 distance = irec->br_startoff + irec->br_blockcount - end;
3757                 irec->br_blockcount -= distance;
3758         }
3759 }
3760
3761 /*
3762  * Trim the returned map to the required bounds
3763  */
3764 STATIC void
3765 xfs_bmapi_trim_map(
3766         struct xfs_bmbt_irec    *mval,
3767         struct xfs_bmbt_irec    *got,
3768         xfs_fileoff_t           *bno,
3769         xfs_filblks_t           len,
3770         xfs_fileoff_t           obno,
3771         xfs_fileoff_t           end,
3772         int                     n,
3773         uint32_t                flags)
3774 {
3775         if ((flags & XFS_BMAPI_ENTIRE) ||
3776             got->br_startoff + got->br_blockcount <= obno) {
3777                 *mval = *got;
3778                 if (isnullstartblock(got->br_startblock))
3779                         mval->br_startblock = DELAYSTARTBLOCK;
3780                 return;
3781         }
3782
3783         if (obno > *bno)
3784                 *bno = obno;
3785         ASSERT((*bno >= obno) || (n == 0));
3786         ASSERT(*bno < end);
3787         mval->br_startoff = *bno;
3788         if (isnullstartblock(got->br_startblock))
3789                 mval->br_startblock = DELAYSTARTBLOCK;
3790         else
3791                 mval->br_startblock = got->br_startblock +
3792                                         (*bno - got->br_startoff);
3793         /*
3794          * Return the minimum of what we got and what we asked for for
3795          * the length.  We can use the len variable here because it is
3796          * modified below and we could have been there before coming
3797          * here if the first part of the allocation didn't overlap what
3798          * was asked for.
3799          */
3800         mval->br_blockcount = XFS_FILBLKS_MIN(end - *bno,
3801                         got->br_blockcount - (*bno - got->br_startoff));
3802         mval->br_state = got->br_state;
3803         ASSERT(mval->br_blockcount <= len);
3804         return;
3805 }
3806
3807 /*
3808  * Update and validate the extent map to return
3809  */
3810 STATIC void
3811 xfs_bmapi_update_map(
3812         struct xfs_bmbt_irec    **map,
3813         xfs_fileoff_t           *bno,
3814         xfs_filblks_t           *len,
3815         xfs_fileoff_t           obno,
3816         xfs_fileoff_t           end,
3817         int                     *n,
3818         uint32_t                flags)
3819 {
3820         xfs_bmbt_irec_t *mval = *map;
3821
3822         ASSERT((flags & XFS_BMAPI_ENTIRE) ||
3823                ((mval->br_startoff + mval->br_blockcount) <= end));
3824         ASSERT((flags & XFS_BMAPI_ENTIRE) || (mval->br_blockcount <= *len) ||
3825                (mval->br_startoff < obno));
3826
3827         *bno = mval->br_startoff + mval->br_blockcount;
3828         *len = end - *bno;
3829         if (*n > 0 && mval->br_startoff == mval[-1].br_startoff) {
3830                 /* update previous map with new information */
3831                 ASSERT(mval->br_startblock == mval[-1].br_startblock);
3832                 ASSERT(mval->br_blockcount > mval[-1].br_blockcount);
3833                 ASSERT(mval->br_state == mval[-1].br_state);
3834                 mval[-1].br_blockcount = mval->br_blockcount;
3835                 mval[-1].br_state = mval->br_state;
3836         } else if (*n > 0 && mval->br_startblock != DELAYSTARTBLOCK &&
3837                    mval[-1].br_startblock != DELAYSTARTBLOCK &&
3838                    mval[-1].br_startblock != HOLESTARTBLOCK &&
3839                    mval->br_startblock == mval[-1].br_startblock +
3840                                           mval[-1].br_blockcount &&
3841                    mval[-1].br_state == mval->br_state) {
3842                 ASSERT(mval->br_startoff ==
3843                        mval[-1].br_startoff + mval[-1].br_blockcount);
3844                 mval[-1].br_blockcount += mval->br_blockcount;
3845         } else if (*n > 0 &&
3846                    mval->br_startblock == DELAYSTARTBLOCK &&
3847                    mval[-1].br_startblock == DELAYSTARTBLOCK &&
3848                    mval->br_startoff ==
3849                    mval[-1].br_startoff + mval[-1].br_blockcount) {
3850                 mval[-1].br_blockcount += mval->br_blockcount;
3851                 mval[-1].br_state = mval->br_state;
3852         } else if (!((*n == 0) &&
3853                      ((mval->br_startoff + mval->br_blockcount) <=
3854                       obno))) {
3855                 mval++;
3856                 (*n)++;
3857         }
3858         *map = mval;
3859 }
3860
3861 /*
3862  * Map file blocks to filesystem blocks without allocation.
3863  */
3864 int
3865 xfs_bmapi_read(
3866         struct xfs_inode        *ip,
3867         xfs_fileoff_t           bno,
3868         xfs_filblks_t           len,
3869         struct xfs_bmbt_irec    *mval,
3870         int                     *nmap,
3871         uint32_t                flags)
3872 {
3873         struct xfs_mount        *mp = ip->i_mount;
3874         int                     whichfork = xfs_bmapi_whichfork(flags);
3875         struct xfs_ifork        *ifp = xfs_ifork_ptr(ip, whichfork);
3876         struct xfs_bmbt_irec    got;
3877         xfs_fileoff_t           obno;
3878         xfs_fileoff_t           end;
3879         struct xfs_iext_cursor  icur;
3880         int                     error;
3881         bool                    eof = false;
3882         int                     n = 0;
3883
3884         ASSERT(*nmap >= 1);
3885         ASSERT(!(flags & ~(XFS_BMAPI_ATTRFORK | XFS_BMAPI_ENTIRE)));
3886         ASSERT(xfs_isilocked(ip, XFS_ILOCK_SHARED|XFS_ILOCK_EXCL));
3887
3888         if (WARN_ON_ONCE(!ifp))
3889                 return -EFSCORRUPTED;
3890
3891         if (XFS_IS_CORRUPT(mp, !xfs_ifork_has_extents(ifp)) ||
3892             XFS_TEST_ERROR(false, mp, XFS_ERRTAG_BMAPIFORMAT))
3893                 return -EFSCORRUPTED;
3894
3895         if (xfs_is_shutdown(mp))
3896                 return -EIO;
3897
3898         XFS_STATS_INC(mp, xs_blk_mapr);
3899
3900         error = xfs_iread_extents(NULL, ip, whichfork);
3901         if (error)
3902                 return error;
3903
3904         if (!xfs_iext_lookup_extent(ip, ifp, bno, &icur, &got))
3905                 eof = true;
3906         end = bno + len;
3907         obno = bno;
3908
3909         while (bno < end && n < *nmap) {
3910                 /* Reading past eof, act as though there's a hole up to end. */
3911                 if (eof)
3912                         got.br_startoff = end;
3913                 if (got.br_startoff > bno) {
3914                         /* Reading in a hole.  */
3915                         mval->br_startoff = bno;
3916                         mval->br_startblock = HOLESTARTBLOCK;
3917                         mval->br_blockcount =
3918                                 XFS_FILBLKS_MIN(len, got.br_startoff - bno);
3919                         mval->br_state = XFS_EXT_NORM;
3920                         bno += mval->br_blockcount;
3921                         len -= mval->br_blockcount;
3922                         mval++;
3923                         n++;
3924                         continue;
3925                 }
3926
3927                 /* set up the extent map to return. */
3928                 xfs_bmapi_trim_map(mval, &got, &bno, len, obno, end, n, flags);
3929                 xfs_bmapi_update_map(&mval, &bno, &len, obno, end, &n, flags);
3930
3931                 /* If we're done, stop now. */
3932                 if (bno >= end || n >= *nmap)
3933                         break;
3934
3935                 /* Else go on to the next record. */
3936                 if (!xfs_iext_next_extent(ifp, &icur, &got))
3937                         eof = true;
3938         }
3939         *nmap = n;
3940         return 0;
3941 }
3942
3943 /*
3944  * Add a delayed allocation extent to an inode. Blocks are reserved from the
3945  * global pool and the extent inserted into the inode in-core extent tree.
3946  *
3947  * On entry, got refers to the first extent beyond the offset of the extent to
3948  * allocate or eof is specified if no such extent exists. On return, got refers
3949  * to the extent record that was inserted to the inode fork.
3950  *
3951  * Note that the allocated extent may have been merged with contiguous extents
3952  * during insertion into the inode fork. Thus, got does not reflect the current
3953  * state of the inode fork on return. If necessary, the caller can use lastx to
3954  * look up the updated record in the inode fork.
3955  */
3956 int
3957 xfs_bmapi_reserve_delalloc(
3958         struct xfs_inode        *ip,
3959         int                     whichfork,
3960         xfs_fileoff_t           off,
3961         xfs_filblks_t           len,
3962         xfs_filblks_t           prealloc,
3963         struct xfs_bmbt_irec    *got,
3964         struct xfs_iext_cursor  *icur,
3965         int                     eof)
3966 {
3967         struct xfs_mount        *mp = ip->i_mount;
3968         struct xfs_ifork        *ifp = xfs_ifork_ptr(ip, whichfork);
3969         xfs_extlen_t            alen;
3970         xfs_extlen_t            indlen;
3971         int                     error;
3972         xfs_fileoff_t           aoff = off;
3973
3974         /*
3975          * Cap the alloc length. Keep track of prealloc so we know whether to
3976          * tag the inode before we return.
3977          */
3978         alen = XFS_FILBLKS_MIN(len + prealloc, XFS_MAX_BMBT_EXTLEN);
3979         if (!eof)
3980                 alen = XFS_FILBLKS_MIN(alen, got->br_startoff - aoff);
3981         if (prealloc && alen >= len)
3982                 prealloc = alen - len;
3983
3984         /* Figure out the extent size, adjust alen */
3985         if (whichfork == XFS_COW_FORK) {
3986                 struct xfs_bmbt_irec    prev;
3987                 xfs_extlen_t            extsz = xfs_get_cowextsz_hint(ip);
3988
3989                 if (!xfs_iext_peek_prev_extent(ifp, icur, &prev))
3990                         prev.br_startoff = NULLFILEOFF;
3991
3992                 error = xfs_bmap_extsize_align(mp, got, &prev, extsz, 0, eof,
3993                                                1, 0, &aoff, &alen);
3994                 ASSERT(!error);
3995         }
3996
3997         /*
3998          * Make a transaction-less quota reservation for delayed allocation
3999          * blocks.  This number gets adjusted later.  We return if we haven't
4000          * allocated blocks already inside this loop.
4001          */
4002         error = xfs_quota_reserve_blkres(ip, alen);
4003         if (error)
4004                 return error;
4005
4006         /*
4007          * Split changing sb for alen and indlen since they could be coming
4008          * from different places.
4009          */
4010         indlen = (xfs_extlen_t)xfs_bmap_worst_indlen(ip, alen);
4011         ASSERT(indlen > 0);
4012
4013         error = xfs_mod_fdblocks(mp, -((int64_t)alen), false);
4014         if (error)
4015                 goto out_unreserve_quota;
4016
4017         error = xfs_mod_fdblocks(mp, -((int64_t)indlen), false);
4018         if (error)
4019                 goto out_unreserve_blocks;
4020
4021
4022         ip->i_delayed_blks += alen;
4023         xfs_mod_delalloc(ip->i_mount, alen + indlen);
4024
4025         got->br_startoff = aoff;
4026         got->br_startblock = nullstartblock(indlen);
4027         got->br_blockcount = alen;
4028         got->br_state = XFS_EXT_NORM;
4029
4030         xfs_bmap_add_extent_hole_delay(ip, whichfork, icur, got);
4031
4032         /*
4033          * Tag the inode if blocks were preallocated. Note that COW fork
4034          * preallocation can occur at the start or end of the extent, even when
4035          * prealloc == 0, so we must also check the aligned offset and length.
4036          */
4037         if (whichfork == XFS_DATA_FORK && prealloc)
4038                 xfs_inode_set_eofblocks_tag(ip);
4039         if (whichfork == XFS_COW_FORK && (prealloc || aoff < off || alen > len))
4040                 xfs_inode_set_cowblocks_tag(ip);
4041
4042         return 0;
4043
4044 out_unreserve_blocks:
4045         xfs_mod_fdblocks(mp, alen, false);
4046 out_unreserve_quota:
4047         if (XFS_IS_QUOTA_ON(mp))
4048                 xfs_quota_unreserve_blkres(ip, alen);
4049         return error;
4050 }
4051
4052 static int
4053 xfs_bmap_alloc_userdata(
4054         struct xfs_bmalloca     *bma)
4055 {
4056         struct xfs_mount        *mp = bma->ip->i_mount;
4057         int                     whichfork = xfs_bmapi_whichfork(bma->flags);
4058         int                     error;
4059
4060         /*
4061          * Set the data type being allocated. For the data fork, the first data
4062          * in the file is treated differently to all other allocations. For the
4063          * attribute fork, we only need to ensure the allocated range is not on
4064          * the busy list.
4065          */
4066         bma->datatype = XFS_ALLOC_NOBUSY;
4067         if (whichfork == XFS_DATA_FORK || whichfork == XFS_COW_FORK) {
4068                 bma->datatype |= XFS_ALLOC_USERDATA;
4069                 if (bma->offset == 0)
4070                         bma->datatype |= XFS_ALLOC_INITIAL_USER_DATA;
4071
4072                 if (mp->m_dalign && bma->length >= mp->m_dalign) {
4073                         error = xfs_bmap_isaeof(bma, whichfork);
4074                         if (error)
4075                                 return error;
4076                 }
4077
4078                 if (XFS_IS_REALTIME_INODE(bma->ip))
4079                         return xfs_bmap_rtalloc(bma);
4080         }
4081
4082         if (unlikely(XFS_TEST_ERROR(false, mp,
4083                         XFS_ERRTAG_BMAP_ALLOC_MINLEN_EXTENT)))
4084                 return xfs_bmap_exact_minlen_extent_alloc(bma);
4085
4086         return xfs_bmap_btalloc(bma);
4087 }
4088
4089 static int
4090 xfs_bmapi_allocate(
4091         struct xfs_bmalloca     *bma)
4092 {
4093         struct xfs_mount        *mp = bma->ip->i_mount;
4094         int                     whichfork = xfs_bmapi_whichfork(bma->flags);
4095         struct xfs_ifork        *ifp = xfs_ifork_ptr(bma->ip, whichfork);
4096         int                     tmp_logflags = 0;
4097         int                     error;
4098
4099         ASSERT(bma->length > 0);
4100
4101         /*
4102          * For the wasdelay case, we could also just allocate the stuff asked
4103          * for in this bmap call but that wouldn't be as good.
4104          */
4105         if (bma->wasdel) {
4106                 bma->length = (xfs_extlen_t)bma->got.br_blockcount;
4107                 bma->offset = bma->got.br_startoff;
4108                 if (!xfs_iext_peek_prev_extent(ifp, &bma->icur, &bma->prev))
4109                         bma->prev.br_startoff = NULLFILEOFF;
4110         } else {
4111                 bma->length = XFS_FILBLKS_MIN(bma->length, XFS_MAX_BMBT_EXTLEN);
4112                 if (!bma->eof)
4113                         bma->length = XFS_FILBLKS_MIN(bma->length,
4114                                         bma->got.br_startoff - bma->offset);
4115         }
4116
4117         if (bma->flags & XFS_BMAPI_CONTIG)
4118                 bma->minlen = bma->length;
4119         else
4120                 bma->minlen = 1;
4121
4122         if (bma->flags & XFS_BMAPI_METADATA) {
4123                 if (unlikely(XFS_TEST_ERROR(false, mp,
4124                                 XFS_ERRTAG_BMAP_ALLOC_MINLEN_EXTENT)))
4125                         error = xfs_bmap_exact_minlen_extent_alloc(bma);
4126                 else
4127                         error = xfs_bmap_btalloc(bma);
4128         } else {
4129                 error = xfs_bmap_alloc_userdata(bma);
4130         }
4131         if (error || bma->blkno == NULLFSBLOCK)
4132                 return error;
4133
4134         if (bma->flags & XFS_BMAPI_ZERO) {
4135                 error = xfs_zero_extent(bma->ip, bma->blkno, bma->length);
4136                 if (error)
4137                         return error;
4138         }
4139
4140         if (ifp->if_format == XFS_DINODE_FMT_BTREE && !bma->cur)
4141                 bma->cur = xfs_bmbt_init_cursor(mp, bma->tp, bma->ip, whichfork);
4142         /*
4143          * Bump the number of extents we've allocated
4144          * in this call.
4145          */
4146         bma->nallocs++;
4147
4148         if (bma->cur)
4149                 bma->cur->bc_ino.flags =
4150                         bma->wasdel ? XFS_BTCUR_BMBT_WASDEL : 0;
4151
4152         bma->got.br_startoff = bma->offset;
4153         bma->got.br_startblock = bma->blkno;
4154         bma->got.br_blockcount = bma->length;
4155         bma->got.br_state = XFS_EXT_NORM;
4156
4157         if (bma->flags & XFS_BMAPI_PREALLOC)
4158                 bma->got.br_state = XFS_EXT_UNWRITTEN;
4159
4160         if (bma->wasdel)
4161                 error = xfs_bmap_add_extent_delay_real(bma, whichfork);
4162         else
4163                 error = xfs_bmap_add_extent_hole_real(bma->tp, bma->ip,
4164                                 whichfork, &bma->icur, &bma->cur, &bma->got,
4165                                 &bma->logflags, bma->flags);
4166
4167         bma->logflags |= tmp_logflags;
4168         if (error)
4169                 return error;
4170
4171         /*
4172          * Update our extent pointer, given that xfs_bmap_add_extent_delay_real
4173          * or xfs_bmap_add_extent_hole_real might have merged it into one of
4174          * the neighbouring ones.
4175          */
4176         xfs_iext_get_extent(ifp, &bma->icur, &bma->got);
4177
4178         ASSERT(bma->got.br_startoff <= bma->offset);
4179         ASSERT(bma->got.br_startoff + bma->got.br_blockcount >=
4180                bma->offset + bma->length);
4181         ASSERT(bma->got.br_state == XFS_EXT_NORM ||
4182                bma->got.br_state == XFS_EXT_UNWRITTEN);
4183         return 0;
4184 }
4185
4186 STATIC int
4187 xfs_bmapi_convert_unwritten(
4188         struct xfs_bmalloca     *bma,
4189         struct xfs_bmbt_irec    *mval,
4190         xfs_filblks_t           len,
4191         uint32_t                flags)
4192 {
4193         int                     whichfork = xfs_bmapi_whichfork(flags);
4194         struct xfs_ifork        *ifp = xfs_ifork_ptr(bma->ip, whichfork);
4195         int                     tmp_logflags = 0;
4196         int                     error;
4197
4198         /* check if we need to do unwritten->real conversion */
4199         if (mval->br_state == XFS_EXT_UNWRITTEN &&
4200             (flags & XFS_BMAPI_PREALLOC))
4201                 return 0;
4202
4203         /* check if we need to do real->unwritten conversion */
4204         if (mval->br_state == XFS_EXT_NORM &&
4205             (flags & (XFS_BMAPI_PREALLOC | XFS_BMAPI_CONVERT)) !=
4206                         (XFS_BMAPI_PREALLOC | XFS_BMAPI_CONVERT))
4207                 return 0;
4208
4209         /*
4210          * Modify (by adding) the state flag, if writing.
4211          */
4212         ASSERT(mval->br_blockcount <= len);
4213         if (ifp->if_format == XFS_DINODE_FMT_BTREE && !bma->cur) {
4214                 bma->cur = xfs_bmbt_init_cursor(bma->ip->i_mount, bma->tp,
4215                                         bma->ip, whichfork);
4216         }
4217         mval->br_state = (mval->br_state == XFS_EXT_UNWRITTEN)
4218                                 ? XFS_EXT_NORM : XFS_EXT_UNWRITTEN;
4219
4220         /*
4221          * Before insertion into the bmbt, zero the range being converted
4222          * if required.
4223          */
4224         if (flags & XFS_BMAPI_ZERO) {
4225                 error = xfs_zero_extent(bma->ip, mval->br_startblock,
4226                                         mval->br_blockcount);
4227                 if (error)
4228                         return error;
4229         }
4230
4231         error = xfs_bmap_add_extent_unwritten_real(bma->tp, bma->ip, whichfork,
4232                         &bma->icur, &bma->cur, mval, &tmp_logflags);
4233         /*
4234          * Log the inode core unconditionally in the unwritten extent conversion
4235          * path because the conversion might not have done so (e.g., if the
4236          * extent count hasn't changed). We need to make sure the inode is dirty
4237          * in the transaction for the sake of fsync(), even if nothing has
4238          * changed, because fsync() will not force the log for this transaction
4239          * unless it sees the inode pinned.
4240          *
4241          * Note: If we're only converting cow fork extents, there aren't
4242          * any on-disk updates to make, so we don't need to log anything.
4243          */
4244         if (whichfork != XFS_COW_FORK)
4245                 bma->logflags |= tmp_logflags | XFS_ILOG_CORE;
4246         if (error)
4247                 return error;
4248
4249         /*
4250          * Update our extent pointer, given that
4251          * xfs_bmap_add_extent_unwritten_real might have merged it into one
4252          * of the neighbouring ones.
4253          */
4254         xfs_iext_get_extent(ifp, &bma->icur, &bma->got);
4255
4256         /*
4257          * We may have combined previously unwritten space with written space,
4258          * so generate another request.
4259          */
4260         if (mval->br_blockcount < len)
4261                 return -EAGAIN;
4262         return 0;
4263 }
4264
4265 xfs_extlen_t
4266 xfs_bmapi_minleft(
4267         struct xfs_trans        *tp,
4268         struct xfs_inode        *ip,
4269         int                     fork)
4270 {
4271         struct xfs_ifork        *ifp = xfs_ifork_ptr(ip, fork);
4272
4273         if (tp && tp->t_highest_agno != NULLAGNUMBER)
4274                 return 0;
4275         if (ifp->if_format != XFS_DINODE_FMT_BTREE)
4276                 return 1;
4277         return be16_to_cpu(ifp->if_broot->bb_level) + 1;
4278 }
4279
4280 /*
4281  * Log whatever the flags say, even if error.  Otherwise we might miss detecting
4282  * a case where the data is changed, there's an error, and it's not logged so we
4283  * don't shutdown when we should.  Don't bother logging extents/btree changes if
4284  * we converted to the other format.
4285  */
4286 static void
4287 xfs_bmapi_finish(
4288         struct xfs_bmalloca     *bma,
4289         int                     whichfork,
4290         int                     error)
4291 {
4292         struct xfs_ifork        *ifp = xfs_ifork_ptr(bma->ip, whichfork);
4293
4294         if ((bma->logflags & xfs_ilog_fext(whichfork)) &&
4295             ifp->if_format != XFS_DINODE_FMT_EXTENTS)
4296                 bma->logflags &= ~xfs_ilog_fext(whichfork);
4297         else if ((bma->logflags & xfs_ilog_fbroot(whichfork)) &&
4298                  ifp->if_format != XFS_DINODE_FMT_BTREE)
4299                 bma->logflags &= ~xfs_ilog_fbroot(whichfork);
4300
4301         if (bma->logflags)
4302                 xfs_trans_log_inode(bma->tp, bma->ip, bma->logflags);
4303         if (bma->cur)
4304                 xfs_btree_del_cursor(bma->cur, error);
4305 }
4306
4307 /*
4308  * Map file blocks to filesystem blocks, and allocate blocks or convert the
4309  * extent state if necessary.  Details behaviour is controlled by the flags
4310  * parameter.  Only allocates blocks from a single allocation group, to avoid
4311  * locking problems.
4312  */
4313 int
4314 xfs_bmapi_write(
4315         struct xfs_trans        *tp,            /* transaction pointer */
4316         struct xfs_inode        *ip,            /* incore inode */
4317         xfs_fileoff_t           bno,            /* starting file offs. mapped */
4318         xfs_filblks_t           len,            /* length to map in file */
4319         uint32_t                flags,          /* XFS_BMAPI_... */
4320         xfs_extlen_t            total,          /* total blocks needed */
4321         struct xfs_bmbt_irec    *mval,          /* output: map values */
4322         int                     *nmap)          /* i/o: mval size/count */
4323 {
4324         struct xfs_bmalloca     bma = {
4325                 .tp             = tp,
4326                 .ip             = ip,
4327                 .total          = total,
4328         };
4329         struct xfs_mount        *mp = ip->i_mount;
4330         int                     whichfork = xfs_bmapi_whichfork(flags);
4331         struct xfs_ifork        *ifp = xfs_ifork_ptr(ip, whichfork);
4332         xfs_fileoff_t           end;            /* end of mapped file region */
4333         bool                    eof = false;    /* after the end of extents */
4334         int                     error;          /* error return */
4335         int                     n;              /* current extent index */
4336         xfs_fileoff_t           obno;           /* old block number (offset) */
4337
4338 #ifdef DEBUG
4339         xfs_fileoff_t           orig_bno;       /* original block number value */
4340         int                     orig_flags;     /* original flags arg value */
4341         xfs_filblks_t           orig_len;       /* original value of len arg */
4342         struct xfs_bmbt_irec    *orig_mval;     /* original value of mval */
4343         int                     orig_nmap;      /* original value of *nmap */
4344
4345         orig_bno = bno;
4346         orig_len = len;
4347         orig_flags = flags;
4348         orig_mval = mval;
4349         orig_nmap = *nmap;
4350 #endif
4351
4352         ASSERT(*nmap >= 1);
4353         ASSERT(*nmap <= XFS_BMAP_MAX_NMAP);
4354         ASSERT(tp != NULL);
4355         ASSERT(len > 0);
4356         ASSERT(ifp->if_format != XFS_DINODE_FMT_LOCAL);
4357         ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
4358         ASSERT(!(flags & XFS_BMAPI_REMAP));
4359
4360         /* zeroing is for currently only for data extents, not metadata */
4361         ASSERT((flags & (XFS_BMAPI_METADATA | XFS_BMAPI_ZERO)) !=
4362                         (XFS_BMAPI_METADATA | XFS_BMAPI_ZERO));
4363         /*
4364          * we can allocate unwritten extents or pre-zero allocated blocks,
4365          * but it makes no sense to do both at once. This would result in
4366          * zeroing the unwritten extent twice, but it still being an
4367          * unwritten extent....
4368          */
4369         ASSERT((flags & (XFS_BMAPI_PREALLOC | XFS_BMAPI_ZERO)) !=
4370                         (XFS_BMAPI_PREALLOC | XFS_BMAPI_ZERO));
4371
4372         if (XFS_IS_CORRUPT(mp, !xfs_ifork_has_extents(ifp)) ||
4373             XFS_TEST_ERROR(false, mp, XFS_ERRTAG_BMAPIFORMAT)) {
4374                 return -EFSCORRUPTED;
4375         }
4376
4377         if (xfs_is_shutdown(mp))
4378                 return -EIO;
4379
4380         XFS_STATS_INC(mp, xs_blk_mapw);
4381
4382         error = xfs_iread_extents(tp, ip, whichfork);
4383         if (error)
4384                 goto error0;
4385
4386         if (!xfs_iext_lookup_extent(ip, ifp, bno, &bma.icur, &bma.got))
4387                 eof = true;
4388         if (!xfs_iext_peek_prev_extent(ifp, &bma.icur, &bma.prev))
4389                 bma.prev.br_startoff = NULLFILEOFF;
4390         bma.minleft = xfs_bmapi_minleft(tp, ip, whichfork);
4391
4392         n = 0;
4393         end = bno + len;
4394         obno = bno;
4395         while (bno < end && n < *nmap) {
4396                 bool                    need_alloc = false, wasdelay = false;
4397
4398                 /* in hole or beyond EOF? */
4399                 if (eof || bma.got.br_startoff > bno) {
4400                         /*
4401                          * CoW fork conversions should /never/ hit EOF or
4402                          * holes.  There should always be something for us
4403                          * to work on.
4404                          */
4405                         ASSERT(!((flags & XFS_BMAPI_CONVERT) &&
4406                                  (flags & XFS_BMAPI_COWFORK)));
4407
4408                         need_alloc = true;
4409                 } else if (isnullstartblock(bma.got.br_startblock)) {
4410                         wasdelay = true;
4411                 }
4412
4413                 /*
4414                  * First, deal with the hole before the allocated space
4415                  * that we found, if any.
4416                  */
4417                 if (need_alloc || wasdelay) {
4418                         bma.eof = eof;
4419                         bma.conv = !!(flags & XFS_BMAPI_CONVERT);
4420                         bma.wasdel = wasdelay;
4421                         bma.offset = bno;
4422                         bma.flags = flags;
4423
4424                         /*
4425                          * There's a 32/64 bit type mismatch between the
4426                          * allocation length request (which can be 64 bits in
4427                          * length) and the bma length request, which is
4428                          * xfs_extlen_t and therefore 32 bits. Hence we have to
4429                          * check for 32-bit overflows and handle them here.
4430                          */
4431                         if (len > (xfs_filblks_t)XFS_MAX_BMBT_EXTLEN)
4432                                 bma.length = XFS_MAX_BMBT_EXTLEN;
4433                         else
4434                                 bma.length = len;
4435
4436                         ASSERT(len > 0);
4437                         ASSERT(bma.length > 0);
4438                         error = xfs_bmapi_allocate(&bma);
4439                         if (error)
4440                                 goto error0;
4441                         if (bma.blkno == NULLFSBLOCK)
4442                                 break;
4443
4444                         /*
4445                          * If this is a CoW allocation, record the data in
4446                          * the refcount btree for orphan recovery.
4447                          */
4448                         if (whichfork == XFS_COW_FORK)
4449                                 xfs_refcount_alloc_cow_extent(tp, bma.blkno,
4450                                                 bma.length);
4451                 }
4452
4453                 /* Deal with the allocated space we found.  */
4454                 xfs_bmapi_trim_map(mval, &bma.got, &bno, len, obno,
4455                                                         end, n, flags);
4456
4457                 /* Execute unwritten extent conversion if necessary */
4458                 error = xfs_bmapi_convert_unwritten(&bma, mval, len, flags);
4459                 if (error == -EAGAIN)
4460                         continue;
4461                 if (error)
4462                         goto error0;
4463
4464                 /* update the extent map to return */
4465                 xfs_bmapi_update_map(&mval, &bno, &len, obno, end, &n, flags);
4466
4467                 /*
4468                  * If we're done, stop now.  Stop when we've allocated
4469                  * XFS_BMAP_MAX_NMAP extents no matter what.  Otherwise
4470                  * the transaction may get too big.
4471                  */
4472                 if (bno >= end || n >= *nmap || bma.nallocs >= *nmap)
4473                         break;
4474
4475                 /* Else go on to the next record. */
4476                 bma.prev = bma.got;
4477                 if (!xfs_iext_next_extent(ifp, &bma.icur, &bma.got))
4478                         eof = true;
4479         }
4480         *nmap = n;
4481
4482         error = xfs_bmap_btree_to_extents(tp, ip, bma.cur, &bma.logflags,
4483                         whichfork);
4484         if (error)
4485                 goto error0;
4486
4487         ASSERT(ifp->if_format != XFS_DINODE_FMT_BTREE ||
4488                ifp->if_nextents > XFS_IFORK_MAXEXT(ip, whichfork));
4489         xfs_bmapi_finish(&bma, whichfork, 0);
4490         xfs_bmap_validate_ret(orig_bno, orig_len, orig_flags, orig_mval,
4491                 orig_nmap, *nmap);
4492         return 0;
4493 error0:
4494         xfs_bmapi_finish(&bma, whichfork, error);
4495         return error;
4496 }
4497
4498 /*
4499  * Convert an existing delalloc extent to real blocks based on file offset. This
4500  * attempts to allocate the entire delalloc extent and may require multiple
4501  * invocations to allocate the target offset if a large enough physical extent
4502  * is not available.
4503  */
4504 int
4505 xfs_bmapi_convert_delalloc(
4506         struct xfs_inode        *ip,
4507         int                     whichfork,
4508         xfs_off_t               offset,
4509         struct iomap            *iomap,
4510         unsigned int            *seq)
4511 {
4512         struct xfs_ifork        *ifp = xfs_ifork_ptr(ip, whichfork);
4513         struct xfs_mount        *mp = ip->i_mount;
4514         xfs_fileoff_t           offset_fsb = XFS_B_TO_FSBT(mp, offset);
4515         struct xfs_bmalloca     bma = { NULL };
4516         uint16_t                flags = 0;
4517         struct xfs_trans        *tp;
4518         int                     error;
4519
4520         if (whichfork == XFS_COW_FORK)
4521                 flags |= IOMAP_F_SHARED;
4522
4523         /*
4524          * Space for the extent and indirect blocks was reserved when the
4525          * delalloc extent was created so there's no need to do so here.
4526          */
4527         error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, 0, 0,
4528                                 XFS_TRANS_RESERVE, &tp);
4529         if (error)
4530                 return error;
4531
4532         xfs_ilock(ip, XFS_ILOCK_EXCL);
4533         xfs_trans_ijoin(tp, ip, 0);
4534
4535         error = xfs_iext_count_may_overflow(ip, whichfork,
4536                         XFS_IEXT_ADD_NOSPLIT_CNT);
4537         if (error == -EFBIG)
4538                 error = xfs_iext_count_upgrade(tp, ip,
4539                                 XFS_IEXT_ADD_NOSPLIT_CNT);
4540         if (error)
4541                 goto out_trans_cancel;
4542
4543         if (!xfs_iext_lookup_extent(ip, ifp, offset_fsb, &bma.icur, &bma.got) ||
4544             bma.got.br_startoff > offset_fsb) {
4545                 /*
4546                  * No extent found in the range we are trying to convert.  This
4547                  * should only happen for the COW fork, where another thread
4548                  * might have moved the extent to the data fork in the meantime.
4549                  */
4550                 WARN_ON_ONCE(whichfork != XFS_COW_FORK);
4551                 error = -EAGAIN;
4552                 goto out_trans_cancel;
4553         }
4554
4555         /*
4556          * If we find a real extent here we raced with another thread converting
4557          * the extent.  Just return the real extent at this offset.
4558          */
4559         if (!isnullstartblock(bma.got.br_startblock)) {
4560                 xfs_bmbt_to_iomap(ip, iomap, &bma.got, 0, flags,
4561                                 xfs_iomap_inode_sequence(ip, flags));
4562                 *seq = READ_ONCE(ifp->if_seq);
4563                 goto out_trans_cancel;
4564         }
4565
4566         bma.tp = tp;
4567         bma.ip = ip;
4568         bma.wasdel = true;
4569         bma.offset = bma.got.br_startoff;
4570         bma.length = max_t(xfs_filblks_t, bma.got.br_blockcount,
4571                         XFS_MAX_BMBT_EXTLEN);
4572         bma.minleft = xfs_bmapi_minleft(tp, ip, whichfork);
4573
4574         /*
4575          * When we're converting the delalloc reservations backing dirty pages
4576          * in the page cache, we must be careful about how we create the new
4577          * extents:
4578          *
4579          * New CoW fork extents are created unwritten, turned into real extents
4580          * when we're about to write the data to disk, and mapped into the data
4581          * fork after the write finishes.  End of story.
4582          *
4583          * New data fork extents must be mapped in as unwritten and converted
4584          * to real extents after the write succeeds to avoid exposing stale
4585          * disk contents if we crash.
4586          */
4587         bma.flags = XFS_BMAPI_PREALLOC;
4588         if (whichfork == XFS_COW_FORK)
4589                 bma.flags |= XFS_BMAPI_COWFORK;
4590
4591         if (!xfs_iext_peek_prev_extent(ifp, &bma.icur, &bma.prev))
4592                 bma.prev.br_startoff = NULLFILEOFF;
4593
4594         error = xfs_bmapi_allocate(&bma);
4595         if (error)
4596                 goto out_finish;
4597
4598         error = -ENOSPC;
4599         if (WARN_ON_ONCE(bma.blkno == NULLFSBLOCK))
4600                 goto out_finish;
4601         error = -EFSCORRUPTED;
4602         if (WARN_ON_ONCE(!xfs_valid_startblock(ip, bma.got.br_startblock)))
4603                 goto out_finish;
4604
4605         XFS_STATS_ADD(mp, xs_xstrat_bytes, XFS_FSB_TO_B(mp, bma.length));
4606         XFS_STATS_INC(mp, xs_xstrat_quick);
4607
4608         ASSERT(!isnullstartblock(bma.got.br_startblock));
4609         xfs_bmbt_to_iomap(ip, iomap, &bma.got, 0, flags,
4610                                 xfs_iomap_inode_sequence(ip, flags));
4611         *seq = READ_ONCE(ifp->if_seq);
4612
4613         if (whichfork == XFS_COW_FORK)
4614                 xfs_refcount_alloc_cow_extent(tp, bma.blkno, bma.length);
4615
4616         error = xfs_bmap_btree_to_extents(tp, ip, bma.cur, &bma.logflags,
4617                         whichfork);
4618         if (error)
4619                 goto out_finish;
4620
4621         xfs_bmapi_finish(&bma, whichfork, 0);
4622         error = xfs_trans_commit(tp);
4623         xfs_iunlock(ip, XFS_ILOCK_EXCL);
4624         return error;
4625
4626 out_finish:
4627         xfs_bmapi_finish(&bma, whichfork, error);
4628 out_trans_cancel:
4629         xfs_trans_cancel(tp);
4630         xfs_iunlock(ip, XFS_ILOCK_EXCL);
4631         return error;
4632 }
4633
4634 int
4635 xfs_bmapi_remap(
4636         struct xfs_trans        *tp,
4637         struct xfs_inode        *ip,
4638         xfs_fileoff_t           bno,
4639         xfs_filblks_t           len,
4640         xfs_fsblock_t           startblock,
4641         uint32_t                flags)
4642 {
4643         struct xfs_mount        *mp = ip->i_mount;
4644         struct xfs_ifork        *ifp;
4645         struct xfs_btree_cur    *cur = NULL;
4646         struct xfs_bmbt_irec    got;
4647         struct xfs_iext_cursor  icur;
4648         int                     whichfork = xfs_bmapi_whichfork(flags);
4649         int                     logflags = 0, error;
4650
4651         ifp = xfs_ifork_ptr(ip, whichfork);
4652         ASSERT(len > 0);
4653         ASSERT(len <= (xfs_filblks_t)XFS_MAX_BMBT_EXTLEN);
4654         ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
4655         ASSERT(!(flags & ~(XFS_BMAPI_ATTRFORK | XFS_BMAPI_PREALLOC |
4656                            XFS_BMAPI_NORMAP)));
4657         ASSERT((flags & (XFS_BMAPI_ATTRFORK | XFS_BMAPI_PREALLOC)) !=
4658                         (XFS_BMAPI_ATTRFORK | XFS_BMAPI_PREALLOC));
4659
4660         if (XFS_IS_CORRUPT(mp, !xfs_ifork_has_extents(ifp)) ||
4661             XFS_TEST_ERROR(false, mp, XFS_ERRTAG_BMAPIFORMAT)) {
4662                 return -EFSCORRUPTED;
4663         }
4664
4665         if (xfs_is_shutdown(mp))
4666                 return -EIO;
4667
4668         error = xfs_iread_extents(tp, ip, whichfork);
4669         if (error)
4670                 return error;
4671
4672         if (xfs_iext_lookup_extent(ip, ifp, bno, &icur, &got)) {
4673                 /* make sure we only reflink into a hole. */
4674                 ASSERT(got.br_startoff > bno);
4675                 ASSERT(got.br_startoff - bno >= len);
4676         }
4677
4678         ip->i_nblocks += len;
4679         xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
4680
4681         if (ifp->if_format == XFS_DINODE_FMT_BTREE) {
4682                 cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork);
4683                 cur->bc_ino.flags = 0;
4684         }
4685
4686         got.br_startoff = bno;
4687         got.br_startblock = startblock;
4688         got.br_blockcount = len;
4689         if (flags & XFS_BMAPI_PREALLOC)
4690                 got.br_state = XFS_EXT_UNWRITTEN;
4691         else
4692                 got.br_state = XFS_EXT_NORM;
4693
4694         error = xfs_bmap_add_extent_hole_real(tp, ip, whichfork, &icur,
4695                         &cur, &got, &logflags, flags);
4696         if (error)
4697                 goto error0;
4698
4699         error = xfs_bmap_btree_to_extents(tp, ip, cur, &logflags, whichfork);
4700
4701 error0:
4702         if (ip->i_df.if_format != XFS_DINODE_FMT_EXTENTS)
4703                 logflags &= ~XFS_ILOG_DEXT;
4704         else if (ip->i_df.if_format != XFS_DINODE_FMT_BTREE)
4705                 logflags &= ~XFS_ILOG_DBROOT;
4706
4707         if (logflags)
4708                 xfs_trans_log_inode(tp, ip, logflags);
4709         if (cur)
4710                 xfs_btree_del_cursor(cur, error);
4711         return error;
4712 }
4713
4714 /*
4715  * When a delalloc extent is split (e.g., due to a hole punch), the original
4716  * indlen reservation must be shared across the two new extents that are left
4717  * behind.
4718  *
4719  * Given the original reservation and the worst case indlen for the two new
4720  * extents (as calculated by xfs_bmap_worst_indlen()), split the original
4721  * reservation fairly across the two new extents. If necessary, steal available
4722  * blocks from a deleted extent to make up a reservation deficiency (e.g., if
4723  * ores == 1). The number of stolen blocks is returned. The availability and
4724  * subsequent accounting of stolen blocks is the responsibility of the caller.
4725  */
4726 static xfs_filblks_t
4727 xfs_bmap_split_indlen(
4728         xfs_filblks_t                   ores,           /* original res. */
4729         xfs_filblks_t                   *indlen1,       /* ext1 worst indlen */
4730         xfs_filblks_t                   *indlen2,       /* ext2 worst indlen */
4731         xfs_filblks_t                   avail)          /* stealable blocks */
4732 {
4733         xfs_filblks_t                   len1 = *indlen1;
4734         xfs_filblks_t                   len2 = *indlen2;
4735         xfs_filblks_t                   nres = len1 + len2; /* new total res. */
4736         xfs_filblks_t                   stolen = 0;
4737         xfs_filblks_t                   resfactor;
4738
4739         /*
4740          * Steal as many blocks as we can to try and satisfy the worst case
4741          * indlen for both new extents.
4742          */
4743         if (ores < nres && avail)
4744                 stolen = XFS_FILBLKS_MIN(nres - ores, avail);
4745         ores += stolen;
4746
4747          /* nothing else to do if we've satisfied the new reservation */
4748         if (ores >= nres)
4749                 return stolen;
4750
4751         /*
4752          * We can't meet the total required reservation for the two extents.
4753          * Calculate the percent of the overall shortage between both extents
4754          * and apply this percentage to each of the requested indlen values.
4755          * This distributes the shortage fairly and reduces the chances that one
4756          * of the two extents is left with nothing when extents are repeatedly
4757          * split.
4758          */
4759         resfactor = (ores * 100);
4760         do_div(resfactor, nres);
4761         len1 *= resfactor;
4762         do_div(len1, 100);
4763         len2 *= resfactor;
4764         do_div(len2, 100);
4765         ASSERT(len1 + len2 <= ores);
4766         ASSERT(len1 < *indlen1 && len2 < *indlen2);
4767
4768         /*
4769          * Hand out the remainder to each extent. If one of the two reservations
4770          * is zero, we want to make sure that one gets a block first. The loop
4771          * below starts with len1, so hand len2 a block right off the bat if it
4772          * is zero.
4773          */
4774         ores -= (len1 + len2);
4775         ASSERT((*indlen1 - len1) + (*indlen2 - len2) >= ores);
4776         if (ores && !len2 && *indlen2) {
4777                 len2++;
4778                 ores--;
4779         }
4780         while (ores) {
4781                 if (len1 < *indlen1) {
4782                         len1++;
4783                         ores--;
4784                 }
4785                 if (!ores)
4786                         break;
4787                 if (len2 < *indlen2) {
4788                         len2++;
4789                         ores--;
4790                 }
4791         }
4792
4793         *indlen1 = len1;
4794         *indlen2 = len2;
4795
4796         return stolen;
4797 }
4798
4799 int
4800 xfs_bmap_del_extent_delay(
4801         struct xfs_inode        *ip,
4802         int                     whichfork,
4803         struct xfs_iext_cursor  *icur,
4804         struct xfs_bmbt_irec    *got,
4805         struct xfs_bmbt_irec    *del)
4806 {
4807         struct xfs_mount        *mp = ip->i_mount;
4808         struct xfs_ifork        *ifp = xfs_ifork_ptr(ip, whichfork);
4809         struct xfs_bmbt_irec    new;
4810         int64_t                 da_old, da_new, da_diff = 0;
4811         xfs_fileoff_t           del_endoff, got_endoff;
4812         xfs_filblks_t           got_indlen, new_indlen, stolen;
4813         uint32_t                state = xfs_bmap_fork_to_state(whichfork);
4814         int                     error = 0;
4815         bool                    isrt;
4816
4817         XFS_STATS_INC(mp, xs_del_exlist);
4818
4819         isrt = (whichfork == XFS_DATA_FORK) && XFS_IS_REALTIME_INODE(ip);
4820         del_endoff = del->br_startoff + del->br_blockcount;
4821         got_endoff = got->br_startoff + got->br_blockcount;
4822         da_old = startblockval(got->br_startblock);
4823         da_new = 0;
4824
4825         ASSERT(del->br_blockcount > 0);
4826         ASSERT(got->br_startoff <= del->br_startoff);
4827         ASSERT(got_endoff >= del_endoff);
4828
4829         if (isrt) {
4830                 uint64_t rtexts = XFS_FSB_TO_B(mp, del->br_blockcount);
4831
4832                 do_div(rtexts, mp->m_sb.sb_rextsize);
4833                 xfs_mod_frextents(mp, rtexts);
4834         }
4835
4836         /*
4837          * Update the inode delalloc counter now and wait to update the
4838          * sb counters as we might have to borrow some blocks for the
4839          * indirect block accounting.
4840          */
4841         ASSERT(!isrt);
4842         error = xfs_quota_unreserve_blkres(ip, del->br_blockcount);
4843         if (error)
4844                 return error;
4845         ip->i_delayed_blks -= del->br_blockcount;
4846
4847         if (got->br_startoff == del->br_startoff)
4848                 state |= BMAP_LEFT_FILLING;
4849         if (got_endoff == del_endoff)
4850                 state |= BMAP_RIGHT_FILLING;
4851
4852         switch (state & (BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING)) {
4853         case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING:
4854                 /*
4855                  * Matches the whole extent.  Delete the entry.
4856                  */
4857                 xfs_iext_remove(ip, icur, state);
4858                 xfs_iext_prev(ifp, icur);
4859                 break;
4860         case BMAP_LEFT_FILLING:
4861                 /*
4862                  * Deleting the first part of the extent.
4863                  */
4864                 got->br_startoff = del_endoff;
4865                 got->br_blockcount -= del->br_blockcount;
4866                 da_new = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip,
4867                                 got->br_blockcount), da_old);
4868                 got->br_startblock = nullstartblock((int)da_new);
4869                 xfs_iext_update_extent(ip, state, icur, got);
4870                 break;
4871         case BMAP_RIGHT_FILLING:
4872                 /*
4873                  * Deleting the last part of the extent.
4874                  */
4875                 got->br_blockcount = got->br_blockcount - del->br_blockcount;
4876                 da_new = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip,
4877                                 got->br_blockcount), da_old);
4878                 got->br_startblock = nullstartblock((int)da_new);
4879                 xfs_iext_update_extent(ip, state, icur, got);
4880                 break;
4881         case 0:
4882                 /*
4883                  * Deleting the middle of the extent.
4884                  *
4885                  * Distribute the original indlen reservation across the two new
4886                  * extents.  Steal blocks from the deleted extent if necessary.
4887                  * Stealing blocks simply fudges the fdblocks accounting below.
4888                  * Warn if either of the new indlen reservations is zero as this
4889                  * can lead to delalloc problems.
4890                  */
4891                 got->br_blockcount = del->br_startoff - got->br_startoff;
4892                 got_indlen = xfs_bmap_worst_indlen(ip, got->br_blockcount);
4893
4894                 new.br_blockcount = got_endoff - del_endoff;
4895                 new_indlen = xfs_bmap_worst_indlen(ip, new.br_blockcount);
4896
4897                 WARN_ON_ONCE(!got_indlen || !new_indlen);
4898                 stolen = xfs_bmap_split_indlen(da_old, &got_indlen, &new_indlen,
4899                                                        del->br_blockcount);
4900
4901                 got->br_startblock = nullstartblock((int)got_indlen);
4902
4903                 new.br_startoff = del_endoff;
4904                 new.br_state = got->br_state;
4905                 new.br_startblock = nullstartblock((int)new_indlen);
4906
4907                 xfs_iext_update_extent(ip, state, icur, got);
4908                 xfs_iext_next(ifp, icur);
4909                 xfs_iext_insert(ip, icur, &new, state);
4910
4911                 da_new = got_indlen + new_indlen - stolen;
4912                 del->br_blockcount -= stolen;
4913                 break;
4914         }
4915
4916         ASSERT(da_old >= da_new);
4917         da_diff = da_old - da_new;
4918         if (!isrt)
4919                 da_diff += del->br_blockcount;
4920         if (da_diff) {
4921                 xfs_mod_fdblocks(mp, da_diff, false);
4922                 xfs_mod_delalloc(mp, -da_diff);
4923         }
4924         return error;
4925 }
4926
4927 void
4928 xfs_bmap_del_extent_cow(
4929         struct xfs_inode        *ip,
4930         struct xfs_iext_cursor  *icur,
4931         struct xfs_bmbt_irec    *got,
4932         struct xfs_bmbt_irec    *del)
4933 {
4934         struct xfs_mount        *mp = ip->i_mount;
4935         struct xfs_ifork        *ifp = xfs_ifork_ptr(ip, XFS_COW_FORK);
4936         struct xfs_bmbt_irec    new;
4937         xfs_fileoff_t           del_endoff, got_endoff;
4938         uint32_t                state = BMAP_COWFORK;
4939
4940         XFS_STATS_INC(mp, xs_del_exlist);
4941
4942         del_endoff = del->br_startoff + del->br_blockcount;
4943         got_endoff = got->br_startoff + got->br_blockcount;
4944
4945         ASSERT(del->br_blockcount > 0);
4946         ASSERT(got->br_startoff <= del->br_startoff);
4947         ASSERT(got_endoff >= del_endoff);
4948         ASSERT(!isnullstartblock(got->br_startblock));
4949
4950         if (got->br_startoff == del->br_startoff)
4951                 state |= BMAP_LEFT_FILLING;
4952         if (got_endoff == del_endoff)
4953                 state |= BMAP_RIGHT_FILLING;
4954
4955         switch (state & (BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING)) {
4956         case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING:
4957                 /*
4958                  * Matches the whole extent.  Delete the entry.
4959                  */
4960                 xfs_iext_remove(ip, icur, state);
4961                 xfs_iext_prev(ifp, icur);
4962                 break;
4963         case BMAP_LEFT_FILLING:
4964                 /*
4965                  * Deleting the first part of the extent.
4966                  */
4967                 got->br_startoff = del_endoff;
4968                 got->br_blockcount -= del->br_blockcount;
4969                 got->br_startblock = del->br_startblock + del->br_blockcount;
4970                 xfs_iext_update_extent(ip, state, icur, got);
4971                 break;
4972         case BMAP_RIGHT_FILLING:
4973                 /*
4974                  * Deleting the last part of the extent.
4975                  */
4976                 got->br_blockcount -= del->br_blockcount;
4977                 xfs_iext_update_extent(ip, state, icur, got);
4978                 break;
4979         case 0:
4980                 /*
4981                  * Deleting the middle of the extent.
4982                  */
4983                 got->br_blockcount = del->br_startoff - got->br_startoff;
4984
4985                 new.br_startoff = del_endoff;
4986                 new.br_blockcount = got_endoff - del_endoff;
4987                 new.br_state = got->br_state;
4988                 new.br_startblock = del->br_startblock + del->br_blockcount;
4989
4990                 xfs_iext_update_extent(ip, state, icur, got);
4991                 xfs_iext_next(ifp, icur);
4992                 xfs_iext_insert(ip, icur, &new, state);
4993                 break;
4994         }
4995         ip->i_delayed_blks -= del->br_blockcount;
4996 }
4997
4998 /*
4999  * Called by xfs_bmapi to update file extent records and the btree
5000  * after removing space.
5001  */
5002 STATIC int                              /* error */
5003 xfs_bmap_del_extent_real(
5004         xfs_inode_t             *ip,    /* incore inode pointer */
5005         xfs_trans_t             *tp,    /* current transaction pointer */
5006         struct xfs_iext_cursor  *icur,
5007         struct xfs_btree_cur    *cur,   /* if null, not a btree */
5008         xfs_bmbt_irec_t         *del,   /* data to remove from extents */
5009         int                     *logflagsp, /* inode logging flags */
5010         int                     whichfork, /* data or attr fork */
5011         uint32_t                bflags) /* bmapi flags */
5012 {
5013         xfs_fsblock_t           del_endblock=0; /* first block past del */
5014         xfs_fileoff_t           del_endoff;     /* first offset past del */
5015         int                     do_fx;  /* free extent at end of routine */
5016         int                     error;  /* error return value */
5017         int                     flags = 0;/* inode logging flags */
5018         struct xfs_bmbt_irec    got;    /* current extent entry */
5019         xfs_fileoff_t           got_endoff;     /* first offset past got */
5020         int                     i;      /* temp state */
5021         struct xfs_ifork        *ifp;   /* inode fork pointer */
5022         xfs_mount_t             *mp;    /* mount structure */
5023         xfs_filblks_t           nblks;  /* quota/sb block count */
5024         xfs_bmbt_irec_t         new;    /* new record to be inserted */
5025         /* REFERENCED */
5026         uint                    qfield; /* quota field to update */
5027         uint32_t                state = xfs_bmap_fork_to_state(whichfork);
5028         struct xfs_bmbt_irec    old;
5029
5030         mp = ip->i_mount;
5031         XFS_STATS_INC(mp, xs_del_exlist);
5032
5033         ifp = xfs_ifork_ptr(ip, whichfork);
5034         ASSERT(del->br_blockcount > 0);
5035         xfs_iext_get_extent(ifp, icur, &got);
5036         ASSERT(got.br_startoff <= del->br_startoff);
5037         del_endoff = del->br_startoff + del->br_blockcount;
5038         got_endoff = got.br_startoff + got.br_blockcount;
5039         ASSERT(got_endoff >= del_endoff);
5040         ASSERT(!isnullstartblock(got.br_startblock));
5041         qfield = 0;
5042         error = 0;
5043
5044         /*
5045          * If it's the case where the directory code is running with no block
5046          * reservation, and the deleted block is in the middle of its extent,
5047          * and the resulting insert of an extent would cause transformation to
5048          * btree format, then reject it.  The calling code will then swap blocks
5049          * around instead.  We have to do this now, rather than waiting for the
5050          * conversion to btree format, since the transaction will be dirty then.
5051          */
5052         if (tp->t_blk_res == 0 &&
5053             ifp->if_format == XFS_DINODE_FMT_EXTENTS &&
5054             ifp->if_nextents >= XFS_IFORK_MAXEXT(ip, whichfork) &&
5055             del->br_startoff > got.br_startoff && del_endoff < got_endoff)
5056                 return -ENOSPC;
5057
5058         flags = XFS_ILOG_CORE;
5059         if (whichfork == XFS_DATA_FORK && XFS_IS_REALTIME_INODE(ip)) {
5060                 xfs_filblks_t   len;
5061                 xfs_extlen_t    mod;
5062
5063                 len = div_u64_rem(del->br_blockcount, mp->m_sb.sb_rextsize,
5064                                   &mod);
5065                 ASSERT(mod == 0);
5066
5067                 if (!(bflags & XFS_BMAPI_REMAP)) {
5068                         xfs_fsblock_t   bno;
5069
5070                         bno = div_u64_rem(del->br_startblock,
5071                                         mp->m_sb.sb_rextsize, &mod);
5072                         ASSERT(mod == 0);
5073
5074                         error = xfs_rtfree_extent(tp, bno, (xfs_extlen_t)len);
5075                         if (error)
5076                                 goto done;
5077                 }
5078
5079                 do_fx = 0;
5080                 nblks = len * mp->m_sb.sb_rextsize;
5081                 qfield = XFS_TRANS_DQ_RTBCOUNT;
5082         } else {
5083                 do_fx = 1;
5084                 nblks = del->br_blockcount;
5085                 qfield = XFS_TRANS_DQ_BCOUNT;
5086         }
5087
5088         del_endblock = del->br_startblock + del->br_blockcount;
5089         if (cur) {
5090                 error = xfs_bmbt_lookup_eq(cur, &got, &i);
5091                 if (error)
5092                         goto done;
5093                 if (XFS_IS_CORRUPT(mp, i != 1)) {
5094                         error = -EFSCORRUPTED;
5095                         goto done;
5096                 }
5097         }
5098
5099         if (got.br_startoff == del->br_startoff)
5100                 state |= BMAP_LEFT_FILLING;
5101         if (got_endoff == del_endoff)
5102                 state |= BMAP_RIGHT_FILLING;
5103
5104         switch (state & (BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING)) {
5105         case BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING:
5106                 /*
5107                  * Matches the whole extent.  Delete the entry.
5108                  */
5109                 xfs_iext_remove(ip, icur, state);
5110                 xfs_iext_prev(ifp, icur);
5111                 ifp->if_nextents--;
5112
5113                 flags |= XFS_ILOG_CORE;
5114                 if (!cur) {
5115                         flags |= xfs_ilog_fext(whichfork);
5116                         break;
5117                 }
5118                 if ((error = xfs_btree_delete(cur, &i)))
5119                         goto done;
5120                 if (XFS_IS_CORRUPT(mp, i != 1)) {
5121                         error = -EFSCORRUPTED;
5122                         goto done;
5123                 }
5124                 break;
5125         case BMAP_LEFT_FILLING:
5126                 /*
5127                  * Deleting the first part of the extent.
5128                  */
5129                 got.br_startoff = del_endoff;
5130                 got.br_startblock = del_endblock;
5131                 got.br_blockcount -= del->br_blockcount;
5132                 xfs_iext_update_extent(ip, state, icur, &got);
5133                 if (!cur) {
5134                         flags |= xfs_ilog_fext(whichfork);
5135                         break;
5136                 }
5137                 error = xfs_bmbt_update(cur, &got);
5138                 if (error)
5139                         goto done;
5140                 break;
5141         case BMAP_RIGHT_FILLING:
5142                 /*
5143                  * Deleting the last part of the extent.
5144                  */
5145                 got.br_blockcount -= del->br_blockcount;
5146                 xfs_iext_update_extent(ip, state, icur, &got);
5147                 if (!cur) {
5148                         flags |= xfs_ilog_fext(whichfork);
5149                         break;
5150                 }
5151                 error = xfs_bmbt_update(cur, &got);
5152                 if (error)
5153                         goto done;
5154                 break;
5155         case 0:
5156                 /*
5157                  * Deleting the middle of the extent.
5158                  */
5159
5160                 old = got;
5161
5162                 got.br_blockcount = del->br_startoff - got.br_startoff;
5163                 xfs_iext_update_extent(ip, state, icur, &got);
5164
5165                 new.br_startoff = del_endoff;
5166                 new.br_blockcount = got_endoff - del_endoff;
5167                 new.br_state = got.br_state;
5168                 new.br_startblock = del_endblock;
5169
5170                 flags |= XFS_ILOG_CORE;
5171                 if (cur) {
5172                         error = xfs_bmbt_update(cur, &got);
5173                         if (error)
5174                                 goto done;
5175                         error = xfs_btree_increment(cur, 0, &i);
5176                         if (error)
5177                                 goto done;
5178                         cur->bc_rec.b = new;
5179                         error = xfs_btree_insert(cur, &i);
5180                         if (error && error != -ENOSPC)
5181                                 goto done;
5182                         /*
5183                          * If get no-space back from btree insert, it tried a
5184                          * split, and we have a zero block reservation.  Fix up
5185                          * our state and return the error.
5186                          */
5187                         if (error == -ENOSPC) {
5188                                 /*
5189                                  * Reset the cursor, don't trust it after any
5190                                  * insert operation.
5191                                  */
5192                                 error = xfs_bmbt_lookup_eq(cur, &got, &i);
5193                                 if (error)
5194                                         goto done;
5195                                 if (XFS_IS_CORRUPT(mp, i != 1)) {
5196                                         error = -EFSCORRUPTED;
5197                                         goto done;
5198                                 }
5199                                 /*
5200                                  * Update the btree record back
5201                                  * to the original value.
5202                                  */
5203                                 error = xfs_bmbt_update(cur, &old);
5204                                 if (error)
5205                                         goto done;
5206                                 /*
5207                                  * Reset the extent record back
5208                                  * to the original value.
5209                                  */
5210                                 xfs_iext_update_extent(ip, state, icur, &old);
5211                                 flags = 0;
5212                                 error = -ENOSPC;
5213                                 goto done;
5214                         }
5215                         if (XFS_IS_CORRUPT(mp, i != 1)) {
5216                                 error = -EFSCORRUPTED;
5217                                 goto done;
5218                         }
5219                 } else
5220                         flags |= xfs_ilog_fext(whichfork);
5221
5222                 ifp->if_nextents++;
5223                 xfs_iext_next(ifp, icur);
5224                 xfs_iext_insert(ip, icur, &new, state);
5225                 break;
5226         }
5227
5228         /* remove reverse mapping */
5229         xfs_rmap_unmap_extent(tp, ip, whichfork, del);
5230
5231         /*
5232          * If we need to, add to list of extents to delete.
5233          */
5234         if (do_fx && !(bflags & XFS_BMAPI_REMAP)) {
5235                 if (xfs_is_reflink_inode(ip) && whichfork == XFS_DATA_FORK) {
5236                         xfs_refcount_decrease_extent(tp, del);
5237                 } else {
5238                         error = __xfs_free_extent_later(tp, del->br_startblock,
5239                                         del->br_blockcount, NULL,
5240                                         XFS_AG_RESV_NONE,
5241                                         ((bflags & XFS_BMAPI_NODISCARD) ||
5242                                         del->br_state == XFS_EXT_UNWRITTEN));
5243                         if (error)
5244                                 goto done;
5245                 }
5246         }
5247
5248         /*
5249          * Adjust inode # blocks in the file.
5250          */
5251         if (nblks)
5252                 ip->i_nblocks -= nblks;
5253         /*
5254          * Adjust quota data.
5255          */
5256         if (qfield && !(bflags & XFS_BMAPI_REMAP))
5257                 xfs_trans_mod_dquot_byino(tp, ip, qfield, (long)-nblks);
5258
5259 done:
5260         *logflagsp = flags;
5261         return error;
5262 }
5263
5264 /*
5265  * Unmap (remove) blocks from a file.
5266  * If nexts is nonzero then the number of extents to remove is limited to
5267  * that value.  If not all extents in the block range can be removed then
5268  * *done is set.
5269  */
5270 int                                             /* error */
5271 __xfs_bunmapi(
5272         struct xfs_trans        *tp,            /* transaction pointer */
5273         struct xfs_inode        *ip,            /* incore inode */
5274         xfs_fileoff_t           start,          /* first file offset deleted */
5275         xfs_filblks_t           *rlen,          /* i/o: amount remaining */
5276         uint32_t                flags,          /* misc flags */
5277         xfs_extnum_t            nexts)          /* number of extents max */
5278 {
5279         struct xfs_btree_cur    *cur;           /* bmap btree cursor */
5280         struct xfs_bmbt_irec    del;            /* extent being deleted */
5281         int                     error;          /* error return value */
5282         xfs_extnum_t            extno;          /* extent number in list */
5283         struct xfs_bmbt_irec    got;            /* current extent record */
5284         struct xfs_ifork        *ifp;           /* inode fork pointer */
5285         int                     isrt;           /* freeing in rt area */
5286         int                     logflags;       /* transaction logging flags */
5287         xfs_extlen_t            mod;            /* rt extent offset */
5288         struct xfs_mount        *mp = ip->i_mount;
5289         int                     tmp_logflags;   /* partial logging flags */
5290         int                     wasdel;         /* was a delayed alloc extent */
5291         int                     whichfork;      /* data or attribute fork */
5292         xfs_fsblock_t           sum;
5293         xfs_filblks_t           len = *rlen;    /* length to unmap in file */
5294         xfs_fileoff_t           end;
5295         struct xfs_iext_cursor  icur;
5296         bool                    done = false;
5297
5298         trace_xfs_bunmap(ip, start, len, flags, _RET_IP_);
5299
5300         whichfork = xfs_bmapi_whichfork(flags);
5301         ASSERT(whichfork != XFS_COW_FORK);
5302         ifp = xfs_ifork_ptr(ip, whichfork);
5303         if (XFS_IS_CORRUPT(mp, !xfs_ifork_has_extents(ifp)))
5304                 return -EFSCORRUPTED;
5305         if (xfs_is_shutdown(mp))
5306                 return -EIO;
5307
5308         ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
5309         ASSERT(len > 0);
5310         ASSERT(nexts >= 0);
5311
5312         error = xfs_iread_extents(tp, ip, whichfork);
5313         if (error)
5314                 return error;
5315
5316         if (xfs_iext_count(ifp) == 0) {
5317                 *rlen = 0;
5318                 return 0;
5319         }
5320         XFS_STATS_INC(mp, xs_blk_unmap);
5321         isrt = (whichfork == XFS_DATA_FORK) && XFS_IS_REALTIME_INODE(ip);
5322         end = start + len;
5323
5324         if (!xfs_iext_lookup_extent_before(ip, ifp, &end, &icur, &got)) {
5325                 *rlen = 0;
5326                 return 0;
5327         }
5328         end--;
5329
5330         logflags = 0;
5331         if (ifp->if_format == XFS_DINODE_FMT_BTREE) {
5332                 ASSERT(ifp->if_format == XFS_DINODE_FMT_BTREE);
5333                 cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork);
5334                 cur->bc_ino.flags = 0;
5335         } else
5336                 cur = NULL;
5337
5338         if (isrt) {
5339                 /*
5340                  * Synchronize by locking the bitmap inode.
5341                  */
5342                 xfs_ilock(mp->m_rbmip, XFS_ILOCK_EXCL|XFS_ILOCK_RTBITMAP);
5343                 xfs_trans_ijoin(tp, mp->m_rbmip, XFS_ILOCK_EXCL);
5344                 xfs_ilock(mp->m_rsumip, XFS_ILOCK_EXCL|XFS_ILOCK_RTSUM);
5345                 xfs_trans_ijoin(tp, mp->m_rsumip, XFS_ILOCK_EXCL);
5346         }
5347
5348         extno = 0;
5349         while (end != (xfs_fileoff_t)-1 && end >= start &&
5350                (nexts == 0 || extno < nexts)) {
5351                 /*
5352                  * Is the found extent after a hole in which end lives?
5353                  * Just back up to the previous extent, if so.
5354                  */
5355                 if (got.br_startoff > end &&
5356                     !xfs_iext_prev_extent(ifp, &icur, &got)) {
5357                         done = true;
5358                         break;
5359                 }
5360                 /*
5361                  * Is the last block of this extent before the range
5362                  * we're supposed to delete?  If so, we're done.
5363                  */
5364                 end = XFS_FILEOFF_MIN(end,
5365                         got.br_startoff + got.br_blockcount - 1);
5366                 if (end < start)
5367                         break;
5368                 /*
5369                  * Then deal with the (possibly delayed) allocated space
5370                  * we found.
5371                  */
5372                 del = got;
5373                 wasdel = isnullstartblock(del.br_startblock);
5374
5375                 if (got.br_startoff < start) {
5376                         del.br_startoff = start;
5377                         del.br_blockcount -= start - got.br_startoff;
5378                         if (!wasdel)
5379                                 del.br_startblock += start - got.br_startoff;
5380                 }
5381                 if (del.br_startoff + del.br_blockcount > end + 1)
5382                         del.br_blockcount = end + 1 - del.br_startoff;
5383
5384                 if (!isrt)
5385                         goto delete;
5386
5387                 sum = del.br_startblock + del.br_blockcount;
5388                 div_u64_rem(sum, mp->m_sb.sb_rextsize, &mod);
5389                 if (mod) {
5390                         /*
5391                          * Realtime extent not lined up at the end.
5392                          * The extent could have been split into written
5393                          * and unwritten pieces, or we could just be
5394                          * unmapping part of it.  But we can't really
5395                          * get rid of part of a realtime extent.
5396                          */
5397                         if (del.br_state == XFS_EXT_UNWRITTEN) {
5398                                 /*
5399                                  * This piece is unwritten, or we're not
5400                                  * using unwritten extents.  Skip over it.
5401                                  */
5402                                 ASSERT(end >= mod);
5403                                 end -= mod > del.br_blockcount ?
5404                                         del.br_blockcount : mod;
5405                                 if (end < got.br_startoff &&
5406                                     !xfs_iext_prev_extent(ifp, &icur, &got)) {
5407                                         done = true;
5408                                         break;
5409                                 }
5410                                 continue;
5411                         }
5412                         /*
5413                          * It's written, turn it unwritten.
5414                          * This is better than zeroing it.
5415                          */
5416                         ASSERT(del.br_state == XFS_EXT_NORM);
5417                         ASSERT(tp->t_blk_res > 0);
5418                         /*
5419                          * If this spans a realtime extent boundary,
5420                          * chop it back to the start of the one we end at.
5421                          */
5422                         if (del.br_blockcount > mod) {
5423                                 del.br_startoff += del.br_blockcount - mod;
5424                                 del.br_startblock += del.br_blockcount - mod;
5425                                 del.br_blockcount = mod;
5426                         }
5427                         del.br_state = XFS_EXT_UNWRITTEN;
5428                         error = xfs_bmap_add_extent_unwritten_real(tp, ip,
5429                                         whichfork, &icur, &cur, &del,
5430                                         &logflags);
5431                         if (error)
5432                                 goto error0;
5433                         goto nodelete;
5434                 }
5435                 div_u64_rem(del.br_startblock, mp->m_sb.sb_rextsize, &mod);
5436                 if (mod) {
5437                         xfs_extlen_t off = mp->m_sb.sb_rextsize - mod;
5438
5439                         /*
5440                          * Realtime extent is lined up at the end but not
5441                          * at the front.  We'll get rid of full extents if
5442                          * we can.
5443                          */
5444                         if (del.br_blockcount > off) {
5445                                 del.br_blockcount -= off;
5446                                 del.br_startoff += off;
5447                                 del.br_startblock += off;
5448                         } else if (del.br_startoff == start &&
5449                                    (del.br_state == XFS_EXT_UNWRITTEN ||
5450                                     tp->t_blk_res == 0)) {
5451                                 /*
5452                                  * Can't make it unwritten.  There isn't
5453                                  * a full extent here so just skip it.
5454                                  */
5455                                 ASSERT(end >= del.br_blockcount);
5456                                 end -= del.br_blockcount;
5457                                 if (got.br_startoff > end &&
5458                                     !xfs_iext_prev_extent(ifp, &icur, &got)) {
5459                                         done = true;
5460                                         break;
5461                                 }
5462                                 continue;
5463                         } else if (del.br_state == XFS_EXT_UNWRITTEN) {
5464                                 struct xfs_bmbt_irec    prev;
5465                                 xfs_fileoff_t           unwrite_start;
5466
5467                                 /*
5468                                  * This one is already unwritten.
5469                                  * It must have a written left neighbor.
5470                                  * Unwrite the killed part of that one and
5471                                  * try again.
5472                                  */
5473                                 if (!xfs_iext_prev_extent(ifp, &icur, &prev))
5474                                         ASSERT(0);
5475                                 ASSERT(prev.br_state == XFS_EXT_NORM);
5476                                 ASSERT(!isnullstartblock(prev.br_startblock));
5477                                 ASSERT(del.br_startblock ==
5478                                        prev.br_startblock + prev.br_blockcount);
5479                                 unwrite_start = max3(start,
5480                                                      del.br_startoff - mod,
5481                                                      prev.br_startoff);
5482                                 mod = unwrite_start - prev.br_startoff;
5483                                 prev.br_startoff = unwrite_start;
5484                                 prev.br_startblock += mod;
5485                                 prev.br_blockcount -= mod;
5486                                 prev.br_state = XFS_EXT_UNWRITTEN;
5487                                 error = xfs_bmap_add_extent_unwritten_real(tp,
5488                                                 ip, whichfork, &icur, &cur,
5489                                                 &prev, &logflags);
5490                                 if (error)
5491                                         goto error0;
5492                                 goto nodelete;
5493                         } else {
5494                                 ASSERT(del.br_state == XFS_EXT_NORM);
5495                                 del.br_state = XFS_EXT_UNWRITTEN;
5496                                 error = xfs_bmap_add_extent_unwritten_real(tp,
5497                                                 ip, whichfork, &icur, &cur,
5498                                                 &del, &logflags);
5499                                 if (error)
5500                                         goto error0;
5501                                 goto nodelete;
5502                         }
5503                 }
5504
5505 delete:
5506                 if (wasdel) {
5507                         error = xfs_bmap_del_extent_delay(ip, whichfork, &icur,
5508                                         &got, &del);
5509                 } else {
5510                         error = xfs_bmap_del_extent_real(ip, tp, &icur, cur,
5511                                         &del, &tmp_logflags, whichfork,
5512                                         flags);
5513                         logflags |= tmp_logflags;
5514                 }
5515
5516                 if (error)
5517                         goto error0;
5518
5519                 end = del.br_startoff - 1;
5520 nodelete:
5521                 /*
5522                  * If not done go on to the next (previous) record.
5523                  */
5524                 if (end != (xfs_fileoff_t)-1 && end >= start) {
5525                         if (!xfs_iext_get_extent(ifp, &icur, &got) ||
5526                             (got.br_startoff > end &&
5527                              !xfs_iext_prev_extent(ifp, &icur, &got))) {
5528                                 done = true;
5529                                 break;
5530                         }
5531                         extno++;
5532                 }
5533         }
5534         if (done || end == (xfs_fileoff_t)-1 || end < start)
5535                 *rlen = 0;
5536         else
5537                 *rlen = end - start + 1;
5538
5539         /*
5540          * Convert to a btree if necessary.
5541          */
5542         if (xfs_bmap_needs_btree(ip, whichfork)) {
5543                 ASSERT(cur == NULL);
5544                 error = xfs_bmap_extents_to_btree(tp, ip, &cur, 0,
5545                                 &tmp_logflags, whichfork);
5546                 logflags |= tmp_logflags;
5547         } else {
5548                 error = xfs_bmap_btree_to_extents(tp, ip, cur, &logflags,
5549                         whichfork);
5550         }
5551
5552 error0:
5553         /*
5554          * Log everything.  Do this after conversion, there's no point in
5555          * logging the extent records if we've converted to btree format.
5556          */
5557         if ((logflags & xfs_ilog_fext(whichfork)) &&
5558             ifp->if_format != XFS_DINODE_FMT_EXTENTS)
5559                 logflags &= ~xfs_ilog_fext(whichfork);
5560         else if ((logflags & xfs_ilog_fbroot(whichfork)) &&
5561                  ifp->if_format != XFS_DINODE_FMT_BTREE)
5562                 logflags &= ~xfs_ilog_fbroot(whichfork);
5563         /*
5564          * Log inode even in the error case, if the transaction
5565          * is dirty we'll need to shut down the filesystem.
5566          */
5567         if (logflags)
5568                 xfs_trans_log_inode(tp, ip, logflags);
5569         if (cur) {
5570                 if (!error)
5571                         cur->bc_ino.allocated = 0;
5572                 xfs_btree_del_cursor(cur, error);
5573         }
5574         return error;
5575 }
5576
5577 /* Unmap a range of a file. */
5578 int
5579 xfs_bunmapi(
5580         xfs_trans_t             *tp,
5581         struct xfs_inode        *ip,
5582         xfs_fileoff_t           bno,
5583         xfs_filblks_t           len,
5584         uint32_t                flags,
5585         xfs_extnum_t            nexts,
5586         int                     *done)
5587 {
5588         int                     error;
5589
5590         error = __xfs_bunmapi(tp, ip, bno, &len, flags, nexts);
5591         *done = (len == 0);
5592         return error;
5593 }
5594
5595 /*
5596  * Determine whether an extent shift can be accomplished by a merge with the
5597  * extent that precedes the target hole of the shift.
5598  */
5599 STATIC bool
5600 xfs_bmse_can_merge(
5601         struct xfs_bmbt_irec    *left,  /* preceding extent */
5602         struct xfs_bmbt_irec    *got,   /* current extent to shift */
5603         xfs_fileoff_t           shift)  /* shift fsb */
5604 {
5605         xfs_fileoff_t           startoff;
5606
5607         startoff = got->br_startoff - shift;
5608
5609         /*
5610          * The extent, once shifted, must be adjacent in-file and on-disk with
5611          * the preceding extent.
5612          */
5613         if ((left->br_startoff + left->br_blockcount != startoff) ||
5614             (left->br_startblock + left->br_blockcount != got->br_startblock) ||
5615             (left->br_state != got->br_state) ||
5616             (left->br_blockcount + got->br_blockcount > XFS_MAX_BMBT_EXTLEN))
5617                 return false;
5618
5619         return true;
5620 }
5621
5622 /*
5623  * A bmap extent shift adjusts the file offset of an extent to fill a preceding
5624  * hole in the file. If an extent shift would result in the extent being fully
5625  * adjacent to the extent that currently precedes the hole, we can merge with
5626  * the preceding extent rather than do the shift.
5627  *
5628  * This function assumes the caller has verified a shift-by-merge is possible
5629  * with the provided extents via xfs_bmse_can_merge().
5630  */
5631 STATIC int
5632 xfs_bmse_merge(
5633         struct xfs_trans                *tp,
5634         struct xfs_inode                *ip,
5635         int                             whichfork,
5636         xfs_fileoff_t                   shift,          /* shift fsb */
5637         struct xfs_iext_cursor          *icur,
5638         struct xfs_bmbt_irec            *got,           /* extent to shift */
5639         struct xfs_bmbt_irec            *left,          /* preceding extent */
5640         struct xfs_btree_cur            *cur,
5641         int                             *logflags)      /* output */
5642 {
5643         struct xfs_ifork                *ifp = xfs_ifork_ptr(ip, whichfork);
5644         struct xfs_bmbt_irec            new;
5645         xfs_filblks_t                   blockcount;
5646         int                             error, i;
5647         struct xfs_mount                *mp = ip->i_mount;
5648
5649         blockcount = left->br_blockcount + got->br_blockcount;
5650
5651         ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
5652         ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
5653         ASSERT(xfs_bmse_can_merge(left, got, shift));
5654
5655         new = *left;
5656         new.br_blockcount = blockcount;
5657
5658         /*
5659          * Update the on-disk extent count, the btree if necessary and log the
5660          * inode.
5661          */
5662         ifp->if_nextents--;
5663         *logflags |= XFS_ILOG_CORE;
5664         if (!cur) {
5665                 *logflags |= XFS_ILOG_DEXT;
5666                 goto done;
5667         }
5668
5669         /* lookup and remove the extent to merge */
5670         error = xfs_bmbt_lookup_eq(cur, got, &i);
5671         if (error)
5672                 return error;
5673         if (XFS_IS_CORRUPT(mp, i != 1))
5674                 return -EFSCORRUPTED;
5675
5676         error = xfs_btree_delete(cur, &i);
5677         if (error)
5678                 return error;
5679         if (XFS_IS_CORRUPT(mp, i != 1))
5680                 return -EFSCORRUPTED;
5681
5682         /* lookup and update size of the previous extent */
5683         error = xfs_bmbt_lookup_eq(cur, left, &i);
5684         if (error)
5685                 return error;
5686         if (XFS_IS_CORRUPT(mp, i != 1))
5687                 return -EFSCORRUPTED;
5688
5689         error = xfs_bmbt_update(cur, &new);
5690         if (error)
5691                 return error;
5692
5693         /* change to extent format if required after extent removal */
5694         error = xfs_bmap_btree_to_extents(tp, ip, cur, logflags, whichfork);
5695         if (error)
5696                 return error;
5697
5698 done:
5699         xfs_iext_remove(ip, icur, 0);
5700         xfs_iext_prev(ifp, icur);
5701         xfs_iext_update_extent(ip, xfs_bmap_fork_to_state(whichfork), icur,
5702                         &new);
5703
5704         /* update reverse mapping. rmap functions merge the rmaps for us */
5705         xfs_rmap_unmap_extent(tp, ip, whichfork, got);
5706         memcpy(&new, got, sizeof(new));
5707         new.br_startoff = left->br_startoff + left->br_blockcount;
5708         xfs_rmap_map_extent(tp, ip, whichfork, &new);
5709         return 0;
5710 }
5711
5712 static int
5713 xfs_bmap_shift_update_extent(
5714         struct xfs_trans        *tp,
5715         struct xfs_inode        *ip,
5716         int                     whichfork,
5717         struct xfs_iext_cursor  *icur,
5718         struct xfs_bmbt_irec    *got,
5719         struct xfs_btree_cur    *cur,
5720         int                     *logflags,
5721         xfs_fileoff_t           startoff)
5722 {
5723         struct xfs_mount        *mp = ip->i_mount;
5724         struct xfs_bmbt_irec    prev = *got;
5725         int                     error, i;
5726
5727         *logflags |= XFS_ILOG_CORE;
5728
5729         got->br_startoff = startoff;
5730
5731         if (cur) {
5732                 error = xfs_bmbt_lookup_eq(cur, &prev, &i);
5733                 if (error)
5734                         return error;
5735                 if (XFS_IS_CORRUPT(mp, i != 1))
5736                         return -EFSCORRUPTED;
5737
5738                 error = xfs_bmbt_update(cur, got);
5739                 if (error)
5740                         return error;
5741         } else {
5742                 *logflags |= XFS_ILOG_DEXT;
5743         }
5744
5745         xfs_iext_update_extent(ip, xfs_bmap_fork_to_state(whichfork), icur,
5746                         got);
5747
5748         /* update reverse mapping */
5749         xfs_rmap_unmap_extent(tp, ip, whichfork, &prev);
5750         xfs_rmap_map_extent(tp, ip, whichfork, got);
5751         return 0;
5752 }
5753
5754 int
5755 xfs_bmap_collapse_extents(
5756         struct xfs_trans        *tp,
5757         struct xfs_inode        *ip,
5758         xfs_fileoff_t           *next_fsb,
5759         xfs_fileoff_t           offset_shift_fsb,
5760         bool                    *done)
5761 {
5762         int                     whichfork = XFS_DATA_FORK;
5763         struct xfs_mount        *mp = ip->i_mount;
5764         struct xfs_ifork        *ifp = xfs_ifork_ptr(ip, whichfork);
5765         struct xfs_btree_cur    *cur = NULL;
5766         struct xfs_bmbt_irec    got, prev;
5767         struct xfs_iext_cursor  icur;
5768         xfs_fileoff_t           new_startoff;
5769         int                     error = 0;
5770         int                     logflags = 0;
5771
5772         if (XFS_IS_CORRUPT(mp, !xfs_ifork_has_extents(ifp)) ||
5773             XFS_TEST_ERROR(false, mp, XFS_ERRTAG_BMAPIFORMAT)) {
5774                 return -EFSCORRUPTED;
5775         }
5776
5777         if (xfs_is_shutdown(mp))
5778                 return -EIO;
5779
5780         ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL));
5781
5782         error = xfs_iread_extents(tp, ip, whichfork);
5783         if (error)
5784                 return error;
5785
5786         if (ifp->if_format == XFS_DINODE_FMT_BTREE) {
5787                 cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork);
5788                 cur->bc_ino.flags = 0;
5789         }
5790
5791         if (!xfs_iext_lookup_extent(ip, ifp, *next_fsb, &icur, &got)) {
5792                 *done = true;
5793                 goto del_cursor;
5794         }
5795         if (XFS_IS_CORRUPT(mp, isnullstartblock(got.br_startblock))) {
5796                 error = -EFSCORRUPTED;
5797                 goto del_cursor;
5798         }
5799
5800         new_startoff = got.br_startoff - offset_shift_fsb;
5801         if (xfs_iext_peek_prev_extent(ifp, &icur, &prev)) {
5802                 if (new_startoff < prev.br_startoff + prev.br_blockcount) {
5803                         error = -EINVAL;
5804                         goto del_cursor;
5805                 }
5806
5807                 if (xfs_bmse_can_merge(&prev, &got, offset_shift_fsb)) {
5808                         error = xfs_bmse_merge(tp, ip, whichfork,
5809                                         offset_shift_fsb, &icur, &got, &prev,
5810                                         cur, &logflags);
5811                         if (error)
5812                                 goto del_cursor;
5813                         goto done;
5814                 }
5815         } else {
5816                 if (got.br_startoff < offset_shift_fsb) {
5817                         error = -EINVAL;
5818                         goto del_cursor;
5819                 }
5820         }
5821
5822         error = xfs_bmap_shift_update_extent(tp, ip, whichfork, &icur, &got,
5823                         cur, &logflags, new_startoff);
5824         if (error)
5825                 goto del_cursor;
5826
5827 done:
5828         if (!xfs_iext_next_extent(ifp, &icur, &got)) {
5829                 *done = true;
5830                 goto del_cursor;
5831         }
5832
5833         *next_fsb = got.br_startoff;
5834 del_cursor:
5835         if (cur)
5836                 xfs_btree_del_cursor(cur, error);
5837         if (logflags)
5838                 xfs_trans_log_inode(tp, ip, logflags);
5839         return error;
5840 }
5841
5842 /* Make sure we won't be right-shifting an extent past the maximum bound. */
5843 int
5844 xfs_bmap_can_insert_extents(
5845         struct xfs_inode        *ip,
5846         xfs_fileoff_t           off,
5847         xfs_fileoff_t           shift)
5848 {
5849         struct xfs_bmbt_irec    got;
5850         int                     is_empty;
5851         int                     error = 0;
5852
5853         ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
5854
5855         if (xfs_is_shutdown(ip->i_mount))
5856                 return -EIO;
5857
5858         xfs_ilock(ip, XFS_ILOCK_EXCL);
5859         error = xfs_bmap_last_extent(NULL, ip, XFS_DATA_FORK, &got, &is_empty);
5860         if (!error && !is_empty && got.br_startoff >= off &&
5861             ((got.br_startoff + shift) & BMBT_STARTOFF_MASK) < got.br_startoff)
5862                 error = -EINVAL;
5863         xfs_iunlock(ip, XFS_ILOCK_EXCL);
5864
5865         return error;
5866 }
5867
5868 int
5869 xfs_bmap_insert_extents(
5870         struct xfs_trans        *tp,
5871         struct xfs_inode        *ip,
5872         xfs_fileoff_t           *next_fsb,
5873         xfs_fileoff_t           offset_shift_fsb,
5874         bool                    *done,
5875         xfs_fileoff_t           stop_fsb)
5876 {
5877         int                     whichfork = XFS_DATA_FORK;
5878         struct xfs_mount        *mp = ip->i_mount;
5879         struct xfs_ifork        *ifp = xfs_ifork_ptr(ip, whichfork);
5880         struct xfs_btree_cur    *cur = NULL;
5881         struct xfs_bmbt_irec    got, next;
5882         struct xfs_iext_cursor  icur;
5883         xfs_fileoff_t           new_startoff;
5884         int                     error = 0;
5885         int                     logflags = 0;
5886
5887         if (XFS_IS_CORRUPT(mp, !xfs_ifork_has_extents(ifp)) ||
5888             XFS_TEST_ERROR(false, mp, XFS_ERRTAG_BMAPIFORMAT)) {
5889                 return -EFSCORRUPTED;
5890         }
5891
5892         if (xfs_is_shutdown(mp))
5893                 return -EIO;
5894
5895         ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL));
5896
5897         error = xfs_iread_extents(tp, ip, whichfork);
5898         if (error)
5899                 return error;
5900
5901         if (ifp->if_format == XFS_DINODE_FMT_BTREE) {
5902                 cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork);
5903                 cur->bc_ino.flags = 0;
5904         }
5905
5906         if (*next_fsb == NULLFSBLOCK) {
5907                 xfs_iext_last(ifp, &icur);
5908                 if (!xfs_iext_get_extent(ifp, &icur, &got) ||
5909                     stop_fsb > got.br_startoff) {
5910                         *done = true;
5911                         goto del_cursor;
5912                 }
5913         } else {
5914                 if (!xfs_iext_lookup_extent(ip, ifp, *next_fsb, &icur, &got)) {
5915                         *done = true;
5916                         goto del_cursor;
5917                 }
5918         }
5919         if (XFS_IS_CORRUPT(mp, isnullstartblock(got.br_startblock))) {
5920                 error = -EFSCORRUPTED;
5921                 goto del_cursor;
5922         }
5923
5924         if (XFS_IS_CORRUPT(mp, stop_fsb > got.br_startoff)) {
5925                 error = -EFSCORRUPTED;
5926                 goto del_cursor;
5927         }
5928
5929         new_startoff = got.br_startoff + offset_shift_fsb;
5930         if (xfs_iext_peek_next_extent(ifp, &icur, &next)) {
5931                 if (new_startoff + got.br_blockcount > next.br_startoff) {
5932                         error = -EINVAL;
5933                         goto del_cursor;
5934                 }
5935
5936                 /*
5937                  * Unlike a left shift (which involves a hole punch), a right
5938                  * shift does not modify extent neighbors in any way.  We should
5939                  * never find mergeable extents in this scenario.  Check anyways
5940                  * and warn if we encounter two extents that could be one.
5941                  */
5942                 if (xfs_bmse_can_merge(&got, &next, offset_shift_fsb))
5943                         WARN_ON_ONCE(1);
5944         }
5945
5946         error = xfs_bmap_shift_update_extent(tp, ip, whichfork, &icur, &got,
5947                         cur, &logflags, new_startoff);
5948         if (error)
5949                 goto del_cursor;
5950
5951         if (!xfs_iext_prev_extent(ifp, &icur, &got) ||
5952             stop_fsb >= got.br_startoff + got.br_blockcount) {
5953                 *done = true;
5954                 goto del_cursor;
5955         }
5956
5957         *next_fsb = got.br_startoff;
5958 del_cursor:
5959         if (cur)
5960                 xfs_btree_del_cursor(cur, error);
5961         if (logflags)
5962                 xfs_trans_log_inode(tp, ip, logflags);
5963         return error;
5964 }
5965
5966 /*
5967  * Splits an extent into two extents at split_fsb block such that it is the
5968  * first block of the current_ext. @ext is a target extent to be split.
5969  * @split_fsb is a block where the extents is split.  If split_fsb lies in a
5970  * hole or the first block of extents, just return 0.
5971  */
5972 int
5973 xfs_bmap_split_extent(
5974         struct xfs_trans        *tp,
5975         struct xfs_inode        *ip,
5976         xfs_fileoff_t           split_fsb)
5977 {
5978         int                             whichfork = XFS_DATA_FORK;
5979         struct xfs_ifork                *ifp = xfs_ifork_ptr(ip, whichfork);
5980         struct xfs_btree_cur            *cur = NULL;
5981         struct xfs_bmbt_irec            got;
5982         struct xfs_bmbt_irec            new; /* split extent */
5983         struct xfs_mount                *mp = ip->i_mount;
5984         xfs_fsblock_t                   gotblkcnt; /* new block count for got */
5985         struct xfs_iext_cursor          icur;
5986         int                             error = 0;
5987         int                             logflags = 0;
5988         int                             i = 0;
5989
5990         if (XFS_IS_CORRUPT(mp, !xfs_ifork_has_extents(ifp)) ||
5991             XFS_TEST_ERROR(false, mp, XFS_ERRTAG_BMAPIFORMAT)) {
5992                 return -EFSCORRUPTED;
5993         }
5994
5995         if (xfs_is_shutdown(mp))
5996                 return -EIO;
5997
5998         /* Read in all the extents */
5999         error = xfs_iread_extents(tp, ip, whichfork);
6000         if (error)
6001                 return error;
6002
6003         /*
6004          * If there are not extents, or split_fsb lies in a hole we are done.
6005          */
6006         if (!xfs_iext_lookup_extent(ip, ifp, split_fsb, &icur, &got) ||
6007             got.br_startoff >= split_fsb)
6008                 return 0;
6009
6010         gotblkcnt = split_fsb - got.br_startoff;
6011         new.br_startoff = split_fsb;
6012         new.br_startblock = got.br_startblock + gotblkcnt;
6013         new.br_blockcount = got.br_blockcount - gotblkcnt;
6014         new.br_state = got.br_state;
6015
6016         if (ifp->if_format == XFS_DINODE_FMT_BTREE) {
6017                 cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork);
6018                 cur->bc_ino.flags = 0;
6019                 error = xfs_bmbt_lookup_eq(cur, &got, &i);
6020                 if (error)
6021                         goto del_cursor;
6022                 if (XFS_IS_CORRUPT(mp, i != 1)) {
6023                         error = -EFSCORRUPTED;
6024                         goto del_cursor;
6025                 }
6026         }
6027
6028         got.br_blockcount = gotblkcnt;
6029         xfs_iext_update_extent(ip, xfs_bmap_fork_to_state(whichfork), &icur,
6030                         &got);
6031
6032         logflags = XFS_ILOG_CORE;
6033         if (cur) {
6034                 error = xfs_bmbt_update(cur, &got);
6035                 if (error)
6036                         goto del_cursor;
6037         } else
6038                 logflags |= XFS_ILOG_DEXT;
6039
6040         /* Add new extent */
6041         xfs_iext_next(ifp, &icur);
6042         xfs_iext_insert(ip, &icur, &new, 0);
6043         ifp->if_nextents++;
6044
6045         if (cur) {
6046                 error = xfs_bmbt_lookup_eq(cur, &new, &i);
6047                 if (error)
6048                         goto del_cursor;
6049                 if (XFS_IS_CORRUPT(mp, i != 0)) {
6050                         error = -EFSCORRUPTED;
6051                         goto del_cursor;
6052                 }
6053                 error = xfs_btree_insert(cur, &i);
6054                 if (error)
6055                         goto del_cursor;
6056                 if (XFS_IS_CORRUPT(mp, i != 1)) {
6057                         error = -EFSCORRUPTED;
6058                         goto del_cursor;
6059                 }
6060         }
6061
6062         /*
6063          * Convert to a btree if necessary.
6064          */
6065         if (xfs_bmap_needs_btree(ip, whichfork)) {
6066                 int tmp_logflags; /* partial log flag return val */
6067
6068                 ASSERT(cur == NULL);
6069                 error = xfs_bmap_extents_to_btree(tp, ip, &cur, 0,
6070                                 &tmp_logflags, whichfork);
6071                 logflags |= tmp_logflags;
6072         }
6073
6074 del_cursor:
6075         if (cur) {
6076                 cur->bc_ino.allocated = 0;
6077                 xfs_btree_del_cursor(cur, error);
6078         }
6079
6080         if (logflags)
6081                 xfs_trans_log_inode(tp, ip, logflags);
6082         return error;
6083 }
6084
6085 /* Deferred mapping is only for real extents in the data fork. */
6086 static bool
6087 xfs_bmap_is_update_needed(
6088         struct xfs_bmbt_irec    *bmap)
6089 {
6090         return  bmap->br_startblock != HOLESTARTBLOCK &&
6091                 bmap->br_startblock != DELAYSTARTBLOCK;
6092 }
6093
6094 /* Record a bmap intent. */
6095 static int
6096 __xfs_bmap_add(
6097         struct xfs_trans                *tp,
6098         enum xfs_bmap_intent_type       type,
6099         struct xfs_inode                *ip,
6100         int                             whichfork,
6101         struct xfs_bmbt_irec            *bmap)
6102 {
6103         struct xfs_bmap_intent          *bi;
6104
6105         trace_xfs_bmap_defer(tp->t_mountp,
6106                         XFS_FSB_TO_AGNO(tp->t_mountp, bmap->br_startblock),
6107                         type,
6108                         XFS_FSB_TO_AGBNO(tp->t_mountp, bmap->br_startblock),
6109                         ip->i_ino, whichfork,
6110                         bmap->br_startoff,
6111                         bmap->br_blockcount,
6112                         bmap->br_state);
6113
6114         bi = kmem_cache_alloc(xfs_bmap_intent_cache, GFP_NOFS | __GFP_NOFAIL);
6115         INIT_LIST_HEAD(&bi->bi_list);
6116         bi->bi_type = type;
6117         bi->bi_owner = ip;
6118         bi->bi_whichfork = whichfork;
6119         bi->bi_bmap = *bmap;
6120
6121         xfs_bmap_update_get_group(tp->t_mountp, bi);
6122         xfs_defer_add(tp, XFS_DEFER_OPS_TYPE_BMAP, &bi->bi_list);
6123         return 0;
6124 }
6125
6126 /* Map an extent into a file. */
6127 void
6128 xfs_bmap_map_extent(
6129         struct xfs_trans        *tp,
6130         struct xfs_inode        *ip,
6131         struct xfs_bmbt_irec    *PREV)
6132 {
6133         if (!xfs_bmap_is_update_needed(PREV))
6134                 return;
6135
6136         __xfs_bmap_add(tp, XFS_BMAP_MAP, ip, XFS_DATA_FORK, PREV);
6137 }
6138
6139 /* Unmap an extent out of a file. */
6140 void
6141 xfs_bmap_unmap_extent(
6142         struct xfs_trans        *tp,
6143         struct xfs_inode        *ip,
6144         struct xfs_bmbt_irec    *PREV)
6145 {
6146         if (!xfs_bmap_is_update_needed(PREV))
6147                 return;
6148
6149         __xfs_bmap_add(tp, XFS_BMAP_UNMAP, ip, XFS_DATA_FORK, PREV);
6150 }
6151
6152 /*
6153  * Process one of the deferred bmap operations.  We pass back the
6154  * btree cursor to maintain our lock on the bmapbt between calls.
6155  */
6156 int
6157 xfs_bmap_finish_one(
6158         struct xfs_trans                *tp,
6159         struct xfs_bmap_intent          *bi)
6160 {
6161         struct xfs_bmbt_irec            *bmap = &bi->bi_bmap;
6162         int                             error = 0;
6163
6164         ASSERT(tp->t_highest_agno == NULLAGNUMBER);
6165
6166         trace_xfs_bmap_deferred(tp->t_mountp,
6167                         XFS_FSB_TO_AGNO(tp->t_mountp, bmap->br_startblock),
6168                         bi->bi_type,
6169                         XFS_FSB_TO_AGBNO(tp->t_mountp, bmap->br_startblock),
6170                         bi->bi_owner->i_ino, bi->bi_whichfork,
6171                         bmap->br_startoff, bmap->br_blockcount,
6172                         bmap->br_state);
6173
6174         if (WARN_ON_ONCE(bi->bi_whichfork != XFS_DATA_FORK))
6175                 return -EFSCORRUPTED;
6176
6177         if (XFS_TEST_ERROR(false, tp->t_mountp,
6178                         XFS_ERRTAG_BMAP_FINISH_ONE))
6179                 return -EIO;
6180
6181         switch (bi->bi_type) {
6182         case XFS_BMAP_MAP:
6183                 error = xfs_bmapi_remap(tp, bi->bi_owner, bmap->br_startoff,
6184                                 bmap->br_blockcount, bmap->br_startblock, 0);
6185                 bmap->br_blockcount = 0;
6186                 break;
6187         case XFS_BMAP_UNMAP:
6188                 error = __xfs_bunmapi(tp, bi->bi_owner, bmap->br_startoff,
6189                                 &bmap->br_blockcount, XFS_BMAPI_REMAP, 1);
6190                 break;
6191         default:
6192                 ASSERT(0);
6193                 error = -EFSCORRUPTED;
6194         }
6195
6196         return error;
6197 }
6198
6199 /* Check that an inode's extent does not have invalid flags or bad ranges. */
6200 xfs_failaddr_t
6201 xfs_bmap_validate_extent(
6202         struct xfs_inode        *ip,
6203         int                     whichfork,
6204         struct xfs_bmbt_irec    *irec)
6205 {
6206         struct xfs_mount        *mp = ip->i_mount;
6207
6208         if (!xfs_verify_fileext(mp, irec->br_startoff, irec->br_blockcount))
6209                 return __this_address;
6210
6211         if (XFS_IS_REALTIME_INODE(ip) && whichfork == XFS_DATA_FORK) {
6212                 if (!xfs_verify_rtext(mp, irec->br_startblock,
6213                                           irec->br_blockcount))
6214                         return __this_address;
6215         } else {
6216                 if (!xfs_verify_fsbext(mp, irec->br_startblock,
6217                                            irec->br_blockcount))
6218                         return __this_address;
6219         }
6220         if (irec->br_state != XFS_EXT_NORM && whichfork != XFS_DATA_FORK)
6221                 return __this_address;
6222         return NULL;
6223 }
6224
6225 int __init
6226 xfs_bmap_intent_init_cache(void)
6227 {
6228         xfs_bmap_intent_cache = kmem_cache_create("xfs_bmap_intent",
6229                         sizeof(struct xfs_bmap_intent),
6230                         0, 0, NULL);
6231
6232         return xfs_bmap_intent_cache != NULL ? 0 : -ENOMEM;
6233 }
6234
6235 void
6236 xfs_bmap_intent_destroy_cache(void)
6237 {
6238         kmem_cache_destroy(xfs_bmap_intent_cache);
6239         xfs_bmap_intent_cache = NULL;
6240 }