fs/ocfs2/suballoc.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * suballoc.c
   4  *
   5  * metadata alloc and free
   6  * Inspired by ext3 block groups.
   7  *
   8  * Copyright (C) 2002, 2004 Oracle.  All rights reserved.
   9  */
  10
  11 #include <linux/fs.h>
  12 #include <linux/types.h>
  13 #include <linux/slab.h>
  14 #include <linux/highmem.h>
  15
  16 #include <cluster/masklog.h>
  17
  18 #include "ocfs2.h"
  19
  20 #include "alloc.h"
  21 #include "blockcheck.h"
  22 #include "dlmglue.h"
  23 #include "inode.h"
  24 #include "journal.h"
  25 #include "localalloc.h"
  26 #include "suballoc.h"
  27 #include "super.h"
  28 #include "sysfile.h"
  29 #include "uptodate.h"
  30 #include "ocfs2_trace.h"
  31
  32 #include "buffer_head_io.h"
  33
  34 #define NOT_ALLOC_NEW_GROUP             0
  35 #define ALLOC_NEW_GROUP                 0x1
  36 #define ALLOC_GROUPS_FROM_GLOBAL        0x2
  37
  38 #define OCFS2_MAX_TO_STEAL              1024
  39
  40 struct ocfs2_suballoc_result {
  41         u64             sr_bg_blkno;    /* The bg we allocated from.  Set
  42                                            to 0 when a block group is
  43                                            contiguous. */
  44         u64             sr_bg_stable_blkno; /*
  45                                              * Doesn't change, always
  46                                              * set to target block
  47                                              * group descriptor
  48                                              * block.
  49                                              */
  50         u64             sr_blkno;       /* The first allocated block */
  51         unsigned int    sr_bit_offset;  /* The bit in the bg */
  52         unsigned int    sr_bits;        /* How many bits we claimed */
  53 };
  54
  55 static u64 ocfs2_group_from_res(struct ocfs2_suballoc_result *res)
  56 {
  57         if (res->sr_blkno == 0)
  58                 return 0;
  59
  60         if (res->sr_bg_blkno)
  61                 return res->sr_bg_blkno;
  62
  63         return ocfs2_which_suballoc_group(res->sr_blkno, res->sr_bit_offset);
  64 }
  65
  66 static inline u16 ocfs2_find_victim_chain(struct ocfs2_chain_list *cl);
  67 static int ocfs2_block_group_fill(handle_t *handle,
  68                                   struct inode *alloc_inode,
  69                                   struct buffer_head *bg_bh,
  70                                   u64 group_blkno,
  71                                   unsigned int group_clusters,
  72                                   u16 my_chain,
  73                                   struct ocfs2_chain_list *cl);
  74 static int ocfs2_block_group_alloc(struct ocfs2_super *osb,
  75                                    struct inode *alloc_inode,
  76                                    struct buffer_head *bh,
  77                                    u64 max_block,
  78                                    u64 *last_alloc_group,
  79                                    int flags);
  80
  81 static int ocfs2_cluster_group_search(struct inode *inode,
  82                                       struct buffer_head *group_bh,
  83                                       u32 bits_wanted, u32 min_bits,
  84                                       u64 max_block,
  85                                       struct ocfs2_suballoc_result *res);
  86 static int ocfs2_block_group_search(struct inode *inode,
  87                                     struct buffer_head *group_bh,
  88                                     u32 bits_wanted, u32 min_bits,
  89                                     u64 max_block,
  90                                     struct ocfs2_suballoc_result *res);
  91 static int ocfs2_claim_suballoc_bits(struct ocfs2_alloc_context *ac,
  92                                      handle_t *handle,
  93                                      u32 bits_wanted,
  94                                      u32 min_bits,
  95                                      struct ocfs2_suballoc_result *res);
  96 static int ocfs2_test_bg_bit_allocatable(struct buffer_head *bg_bh,
  97                                          int nr);
  98 static int ocfs2_relink_block_group(handle_t *handle,
  99                                     struct inode *alloc_inode,
 100                                     struct buffer_head *fe_bh,
 101                                     struct buffer_head *bg_bh,
 102                                     struct buffer_head *prev_bg_bh,
 103                                     u16 chain);
 104 static inline int ocfs2_block_group_reasonably_empty(struct ocfs2_group_desc *bg,
 105                                                      u32 wanted);
 106 static inline u32 ocfs2_desc_bitmap_to_cluster_off(struct inode *inode,
 107                                                    u64 bg_blkno,
 108                                                    u16 bg_bit_off);
 109 static inline void ocfs2_block_to_cluster_group(struct inode *inode,
 110                                                 u64 data_blkno,
 111                                                 u64 *bg_blkno,
 112                                                 u16 *bg_bit_off);
 113 static int ocfs2_reserve_clusters_with_limit(struct ocfs2_super *osb,
 114                                              u32 bits_wanted, u64 max_block,
 115                                              int flags,
 116                                              struct ocfs2_alloc_context **ac);
 117
 118 void ocfs2_free_ac_resource(struct ocfs2_alloc_context *ac)
 119 {
 120         struct inode *inode = ac->ac_inode;
 121
 122         if (inode) {
 123                 if (ac->ac_which != OCFS2_AC_USE_LOCAL)
 124                         ocfs2_inode_unlock(inode, 1);
 125
 126                 inode_unlock(inode);
 127
 128                 iput(inode);
 129                 ac->ac_inode = NULL;
 130         }
 131         brelse(ac->ac_bh);
 132         ac->ac_bh = NULL;
 133         ac->ac_resv = NULL;
 134         kfree(ac->ac_find_loc_priv);
 135         ac->ac_find_loc_priv = NULL;
 136 }
 137
 138 void ocfs2_free_alloc_context(struct ocfs2_alloc_context *ac)
 139 {
 140         ocfs2_free_ac_resource(ac);
 141         kfree(ac);
 142 }
 143
 144 static u32 ocfs2_bits_per_group(struct ocfs2_chain_list *cl)
 145 {
 146         return (u32)le16_to_cpu(cl->cl_cpg) * (u32)le16_to_cpu(cl->cl_bpc);
 147 }
 148
 149 #define do_error(fmt, ...)                                              \
 150 do {                                                                    \
 151         if (resize)                                                     \
 152                 mlog(ML_ERROR, fmt, ##__VA_ARGS__);                     \
 153         else                                                            \
 154                 return ocfs2_error(sb, fmt, ##__VA_ARGS__);             \
 155 } while (0)
 156
 157 static int ocfs2_validate_gd_self(struct super_block *sb,
 158                                   struct buffer_head *bh,
 159                                   int resize)
 160 {
 161         struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
 162
 163         if (!OCFS2_IS_VALID_GROUP_DESC(gd)) {
 164                 do_error("Group descriptor #%llu has bad signature %.*s\n",
 165                          (unsigned long long)bh->b_blocknr, 7,
 166                          gd->bg_signature);
 167         }
 168
 169         if (le64_to_cpu(gd->bg_blkno) != bh->b_blocknr) {
 170                 do_error("Group descriptor #%llu has an invalid bg_blkno of %llu\n",
 171                          (unsigned long long)bh->b_blocknr,
 172                          (unsigned long long)le64_to_cpu(gd->bg_blkno));
 173         }
 174
 175         if (le32_to_cpu(gd->bg_generation) != OCFS2_SB(sb)->fs_generation) {
 176                 do_error("Group descriptor #%llu has an invalid fs_generation of #%u\n",
 177                          (unsigned long long)bh->b_blocknr,
 178                          le32_to_cpu(gd->bg_generation));
 179         }
 180
 181         if (le16_to_cpu(gd->bg_free_bits_count) > le16_to_cpu(gd->bg_bits)) {
 182                 do_error("Group descriptor #%llu has bit count %u but claims that %u are free\n",
 183                          (unsigned long long)bh->b_blocknr,
 184                          le16_to_cpu(gd->bg_bits),
 185                          le16_to_cpu(gd->bg_free_bits_count));
 186         }
 187
 188         if (le16_to_cpu(gd->bg_bits) > (8 * le16_to_cpu(gd->bg_size))) {
 189                 do_error("Group descriptor #%llu has bit count %u but max bitmap bits of %u\n",
 190                          (unsigned long long)bh->b_blocknr,
 191                          le16_to_cpu(gd->bg_bits),
 192                          8 * le16_to_cpu(gd->bg_size));
 193         }
 194
 195         return 0;
 196 }
 197
 198 static int ocfs2_validate_gd_parent(struct super_block *sb,
 199                                     struct ocfs2_dinode *di,
 200                                     struct buffer_head *bh,
 201                                     int resize)
 202 {
 203         unsigned int max_bits;
 204         struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
 205
 206         if (di->i_blkno != gd->bg_parent_dinode) {
 207                 do_error("Group descriptor #%llu has bad parent pointer (%llu, expected %llu)\n",
 208                          (unsigned long long)bh->b_blocknr,
 209                          (unsigned long long)le64_to_cpu(gd->bg_parent_dinode),
 210                          (unsigned long long)le64_to_cpu(di->i_blkno));
 211         }
 212
 213         max_bits = le16_to_cpu(di->id2.i_chain.cl_cpg) * le16_to_cpu(di->id2.i_chain.cl_bpc);
 214         if (le16_to_cpu(gd->bg_bits) > max_bits) {
 215                 do_error("Group descriptor #%llu has bit count of %u\n",
 216                          (unsigned long long)bh->b_blocknr,
 217                          le16_to_cpu(gd->bg_bits));
 218         }
 219
 220         /* In resize, we may meet the case bg_chain == cl_next_free_rec. */
 221         if ((le16_to_cpu(gd->bg_chain) >
 222              le16_to_cpu(di->id2.i_chain.cl_next_free_rec)) ||
 223             ((le16_to_cpu(gd->bg_chain) ==
 224              le16_to_cpu(di->id2.i_chain.cl_next_free_rec)) && !resize)) {
 225                 do_error("Group descriptor #%llu has bad chain %u\n",
 226                          (unsigned long long)bh->b_blocknr,
 227                          le16_to_cpu(gd->bg_chain));
 228         }
 229
 230         return 0;
 231 }
 232
 233 #undef do_error
 234
 235 /*
 236  * This version only prints errors.  It does not fail the filesystem, and
 237  * exists only for resize.
 238  */
 239 int ocfs2_check_group_descriptor(struct super_block *sb,
 240                                  struct ocfs2_dinode *di,
 241                                  struct buffer_head *bh)
 242 {
 243         int rc;
 244         struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
 245
 246         BUG_ON(!buffer_uptodate(bh));
 247
 248         /*
 249          * If the ecc fails, we return the error but otherwise
 250          * leave the filesystem running.  We know any error is
 251          * local to this block.
 252          */
 253         rc = ocfs2_validate_meta_ecc(sb, bh->b_data, &gd->bg_check);
 254         if (rc) {
 255                 mlog(ML_ERROR,
 256                      "Checksum failed for group descriptor %llu\n",
 257                      (unsigned long long)bh->b_blocknr);
 258         } else
 259                 rc = ocfs2_validate_gd_self(sb, bh, 1);
 260         if (!rc)
 261                 rc = ocfs2_validate_gd_parent(sb, di, bh, 1);
 262
 263         return rc;
 264 }
 265
 266 static int ocfs2_validate_group_descriptor(struct super_block *sb,
 267                                            struct buffer_head *bh)
 268 {
 269         int rc;
 270         struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
 271
 272         trace_ocfs2_validate_group_descriptor(
 273                                         (unsigned long long)bh->b_blocknr);
 274
 275         BUG_ON(!buffer_uptodate(bh));
 276
 277         /*
 278          * If the ecc fails, we return the error but otherwise
 279          * leave the filesystem running.  We know any error is
 280          * local to this block.
 281          */
 282         rc = ocfs2_validate_meta_ecc(sb, bh->b_data, &gd->bg_check);
 283         if (rc)
 284                 return rc;
 285
 286         /*
 287          * Errors after here are fatal.
 288          */
 289
 290         return ocfs2_validate_gd_self(sb, bh, 0);
 291 }
 292
 293 int ocfs2_read_group_descriptor(struct inode *inode, struct ocfs2_dinode *di,
 294                                 u64 gd_blkno, struct buffer_head **bh)
 295 {
 296         int rc;
 297         struct buffer_head *tmp = *bh;
 298
 299         rc = ocfs2_read_block(INODE_CACHE(inode), gd_blkno, &tmp,
 300                               ocfs2_validate_group_descriptor);
 301         if (rc)
 302                 goto out;
 303
 304         rc = ocfs2_validate_gd_parent(inode->i_sb, di, tmp, 0);
 305         if (rc) {
 306                 brelse(tmp);
 307                 goto out;
 308         }
 309
 310         /* If ocfs2_read_block() got us a new bh, pass it up. */
 311         if (!*bh)
 312                 *bh = tmp;
 313
 314 out:
 315         return rc;
 316 }
 317
 318 static void ocfs2_bg_discontig_add_extent(struct ocfs2_super *osb,
 319                                           struct ocfs2_group_desc *bg,
 320                                           struct ocfs2_chain_list *cl,
 321                                           u64 p_blkno, unsigned int clusters)
 322 {
 323         struct ocfs2_extent_list *el = &bg->bg_list;
 324         struct ocfs2_extent_rec *rec;
 325
 326         BUG_ON(!ocfs2_supports_discontig_bg(osb));
 327         if (!el->l_next_free_rec)
 328                 el->l_count = cpu_to_le16(ocfs2_extent_recs_per_gd(osb->sb));
 329         rec = &el->l_recs[le16_to_cpu(el->l_next_free_rec)];
 330         rec->e_blkno = cpu_to_le64(p_blkno);
 331         rec->e_cpos = cpu_to_le32(le16_to_cpu(bg->bg_bits) /
 332                                   le16_to_cpu(cl->cl_bpc));
 333         rec->e_leaf_clusters = cpu_to_le16(clusters);
 334         le16_add_cpu(&bg->bg_bits, clusters * le16_to_cpu(cl->cl_bpc));
 335         le16_add_cpu(&bg->bg_free_bits_count,
 336                      clusters * le16_to_cpu(cl->cl_bpc));
 337         le16_add_cpu(&el->l_next_free_rec, 1);
 338 }
 339
 340 static int ocfs2_block_group_fill(handle_t *handle,
 341                                   struct inode *alloc_inode,
 342                                   struct buffer_head *bg_bh,
 343                                   u64 group_blkno,
 344                                   unsigned int group_clusters,
 345                                   u16 my_chain,
 346                                   struct ocfs2_chain_list *cl)
 347 {
 348         int status = 0;
 349         struct ocfs2_super *osb = OCFS2_SB(alloc_inode->i_sb);
 350         struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
 351         struct super_block * sb = alloc_inode->i_sb;
 352
 353         if (((unsigned long long) bg_bh->b_blocknr) != group_blkno) {
 354                 status = ocfs2_error(alloc_inode->i_sb,
 355                                      "group block (%llu) != b_blocknr (%llu)\n",
 356                                      (unsigned long long)group_blkno,
 357                                      (unsigned long long) bg_bh->b_blocknr);
 358                 goto bail;
 359         }
 360
 361         status = ocfs2_journal_access_gd(handle,
 362                                          INODE_CACHE(alloc_inode),
 363                                          bg_bh,
 364                                          OCFS2_JOURNAL_ACCESS_CREATE);
 365         if (status < 0) {
 366                 mlog_errno(status);
 367                 goto bail;
 368         }
 369
 370         memset(bg, 0, sb->s_blocksize);
 371         strcpy(bg->bg_signature, OCFS2_GROUP_DESC_SIGNATURE);
 372         bg->bg_generation = cpu_to_le32(osb->fs_generation);
 373         bg->bg_size = cpu_to_le16(ocfs2_group_bitmap_size(sb, 1,
 374                                                 osb->s_feature_incompat));
 375         bg->bg_chain = cpu_to_le16(my_chain);
 376         bg->bg_next_group = cl->cl_recs[my_chain].c_blkno;
 377         bg->bg_parent_dinode = cpu_to_le64(OCFS2_I(alloc_inode)->ip_blkno);
 378         bg->bg_blkno = cpu_to_le64(group_blkno);
 379         if (group_clusters == le16_to_cpu(cl->cl_cpg))
 380                 bg->bg_bits = cpu_to_le16(ocfs2_bits_per_group(cl));
 381         else
 382                 ocfs2_bg_discontig_add_extent(osb, bg, cl, group_blkno,
 383                                               group_clusters);
 384
 385         /* set the 1st bit in the bitmap to account for the descriptor block */
 386         ocfs2_set_bit(0, (unsigned long *)bg->bg_bitmap);
 387         bg->bg_free_bits_count = cpu_to_le16(le16_to_cpu(bg->bg_bits) - 1);
 388
 389         ocfs2_journal_dirty(handle, bg_bh);
 390
 391         /* There is no need to zero out or otherwise initialize the
 392          * other blocks in a group - All valid FS metadata in a block
 393          * group stores the superblock fs_generation value at
 394          * allocation time. */
 395
 396 bail:
 397         if (status)
 398                 mlog_errno(status);
 399         return status;
 400 }
 401
 402 static inline u16 ocfs2_find_smallest_chain(struct ocfs2_chain_list *cl)
 403 {
 404         u16 curr, best;
 405
 406         best = curr = 0;
 407         while (curr < le16_to_cpu(cl->cl_count)) {
 408                 if (le32_to_cpu(cl->cl_recs[best].c_total) >
 409                     le32_to_cpu(cl->cl_recs[curr].c_total))
 410                         best = curr;
 411                 curr++;
 412         }
 413         return best;
 414 }
 415
 416 static struct buffer_head *
 417 ocfs2_block_group_alloc_contig(struct ocfs2_super *osb, handle_t *handle,
 418                                struct inode *alloc_inode,
 419                                struct ocfs2_alloc_context *ac,
 420                                struct ocfs2_chain_list *cl)
 421 {
 422         int status;
 423         u32 bit_off, num_bits;
 424         u64 bg_blkno;
 425         struct buffer_head *bg_bh;
 426         unsigned int alloc_rec = ocfs2_find_smallest_chain(cl);
 427
 428         status = ocfs2_claim_clusters(handle, ac,
 429                                       le16_to_cpu(cl->cl_cpg), &bit_off,
 430                                       &num_bits);
 431         if (status < 0) {
 432                 if (status != -ENOSPC)
 433                         mlog_errno(status);
 434                 goto bail;
 435         }
 436
 437         /* setup the group */
 438         bg_blkno = ocfs2_clusters_to_blocks(osb->sb, bit_off);
 439         trace_ocfs2_block_group_alloc_contig(
 440              (unsigned long long)bg_blkno, alloc_rec);
 441
 442         bg_bh = sb_getblk(osb->sb, bg_blkno);
 443         if (!bg_bh) {
 444                 status = -ENOMEM;
 445                 mlog_errno(status);
 446                 goto bail;
 447         }
 448         ocfs2_set_new_buffer_uptodate(INODE_CACHE(alloc_inode), bg_bh);
 449
 450         status = ocfs2_block_group_fill(handle, alloc_inode, bg_bh,
 451                                         bg_blkno, num_bits, alloc_rec, cl);
 452         if (status < 0) {
 453                 brelse(bg_bh);
 454                 mlog_errno(status);
 455         }
 456
 457 bail:
 458         return status ? ERR_PTR(status) : bg_bh;
 459 }
 460
 461 static int ocfs2_block_group_claim_bits(struct ocfs2_super *osb,
 462                                         handle_t *handle,
 463                                         struct ocfs2_alloc_context *ac,
 464                                         unsigned int min_bits,
 465                                         u32 *bit_off, u32 *num_bits)
 466 {
 467         int status = 0;
 468
 469         while (min_bits) {
 470                 status = ocfs2_claim_clusters(handle, ac, min_bits,
 471                                               bit_off, num_bits);
 472                 if (status != -ENOSPC)
 473                         break;
 474
 475                 min_bits >>= 1;
 476         }
 477
 478         return status;
 479 }
 480
 481 static int ocfs2_block_group_grow_discontig(handle_t *handle,
 482                                             struct inode *alloc_inode,
 483                                             struct buffer_head *bg_bh,
 484                                             struct ocfs2_alloc_context *ac,
 485                                             struct ocfs2_chain_list *cl,
 486                                             unsigned int min_bits)
 487 {
 488         int status;
 489         struct ocfs2_super *osb = OCFS2_SB(alloc_inode->i_sb);
 490         struct ocfs2_group_desc *bg =
 491                 (struct ocfs2_group_desc *)bg_bh->b_data;
 492         unsigned int needed = le16_to_cpu(cl->cl_cpg) -
 493                          le16_to_cpu(bg->bg_bits) / le16_to_cpu(cl->cl_bpc);
 494         u32 p_cpos, clusters;
 495         u64 p_blkno;
 496         struct ocfs2_extent_list *el = &bg->bg_list;
 497
 498         status = ocfs2_journal_access_gd(handle,
 499                                          INODE_CACHE(alloc_inode),
 500                                          bg_bh,
 501                                          OCFS2_JOURNAL_ACCESS_CREATE);
 502         if (status < 0) {
 503                 mlog_errno(status);
 504                 goto bail;
 505         }
 506
 507         while ((needed > 0) && (le16_to_cpu(el->l_next_free_rec) <
 508                                 le16_to_cpu(el->l_count))) {
 509                 if (min_bits > needed)
 510                         min_bits = needed;
 511                 status = ocfs2_block_group_claim_bits(osb, handle, ac,
 512                                                       min_bits, &p_cpos,
 513                                                       &clusters);
 514                 if (status < 0) {
 515                         if (status != -ENOSPC)
 516                                 mlog_errno(status);
 517                         goto bail;
 518                 }
 519                 p_blkno = ocfs2_clusters_to_blocks(osb->sb, p_cpos);
 520                 ocfs2_bg_discontig_add_extent(osb, bg, cl, p_blkno,
 521                                               clusters);
 522
 523                 min_bits = clusters;
 524                 needed = le16_to_cpu(cl->cl_cpg) -
 525                          le16_to_cpu(bg->bg_bits) / le16_to_cpu(cl->cl_bpc);
 526         }
 527
 528         if (needed > 0) {
 529                 /*
 530                  * We have used up all the extent rec but can't fill up
 531                  * the cpg. So bail out.
 532                  */
 533                 status = -ENOSPC;
 534                 goto bail;
 535         }
 536
 537         ocfs2_journal_dirty(handle, bg_bh);
 538
 539 bail:
 540         return status;
 541 }
 542
 543 static void ocfs2_bg_alloc_cleanup(handle_t *handle,
 544                                    struct ocfs2_alloc_context *cluster_ac,
 545                                    struct inode *alloc_inode,
 546                                    struct buffer_head *bg_bh)
 547 {
 548         int i, ret;
 549         struct ocfs2_group_desc *bg;
 550         struct ocfs2_extent_list *el;
 551         struct ocfs2_extent_rec *rec;
 552
 553         if (!bg_bh)
 554                 return;
 555
 556         bg = (struct ocfs2_group_desc *)bg_bh->b_data;
 557         el = &bg->bg_list;
 558         for (i = 0; i < le16_to_cpu(el->l_next_free_rec); i++) {
 559                 rec = &el->l_recs[i];
 560                 ret = ocfs2_free_clusters(handle, cluster_ac->ac_inode,
 561                                           cluster_ac->ac_bh,
 562                                           le64_to_cpu(rec->e_blkno),
 563                                           le16_to_cpu(rec->e_leaf_clusters));
 564                 if (ret)
 565                         mlog_errno(ret);
 566                 /* Try all the clusters to free */
 567         }
 568
 569         ocfs2_remove_from_cache(INODE_CACHE(alloc_inode), bg_bh);
 570         brelse(bg_bh);
 571 }
 572
 573 static struct buffer_head *
 574 ocfs2_block_group_alloc_discontig(handle_t *handle,
 575                                   struct inode *alloc_inode,
 576                                   struct ocfs2_alloc_context *ac,
 577                                   struct ocfs2_chain_list *cl)
 578 {
 579         int status;
 580         u32 bit_off, num_bits;
 581         u64 bg_blkno;
 582         unsigned int min_bits = le16_to_cpu(cl->cl_cpg) >> 1;
 583         struct buffer_head *bg_bh = NULL;
 584         unsigned int alloc_rec = ocfs2_find_smallest_chain(cl);
 585         struct ocfs2_super *osb = OCFS2_SB(alloc_inode->i_sb);
 586
 587         if (!ocfs2_supports_discontig_bg(osb)) {
 588                 status = -ENOSPC;
 589                 goto bail;
 590         }
 591
 592         status = ocfs2_extend_trans(handle,
 593                                     ocfs2_calc_bg_discontig_credits(osb->sb));
 594         if (status) {
 595                 mlog_errno(status);
 596                 goto bail;
 597         }
 598
 599         /*
 600          * We're going to be grabbing from multiple cluster groups.
 601          * We don't have enough credits to relink them all, and the
 602          * cluster groups will be staying in cache for the duration of
 603          * this operation.
 604          */
 605         ac->ac_disable_chain_relink = 1;
 606
 607         /* Claim the first region */
 608         status = ocfs2_block_group_claim_bits(osb, handle, ac, min_bits,
 609                                               &bit_off, &num_bits);
 610         if (status < 0) {
 611                 if (status != -ENOSPC)
 612                         mlog_errno(status);
 613                 goto bail;
 614         }
 615         min_bits = num_bits;
 616
 617         /* setup the group */
 618         bg_blkno = ocfs2_clusters_to_blocks(osb->sb, bit_off);
 619         trace_ocfs2_block_group_alloc_discontig(
 620                                 (unsigned long long)bg_blkno, alloc_rec);
 621
 622         bg_bh = sb_getblk(osb->sb, bg_blkno);
 623         if (!bg_bh) {
 624                 status = -ENOMEM;
 625                 mlog_errno(status);
 626                 goto bail;
 627         }
 628         ocfs2_set_new_buffer_uptodate(INODE_CACHE(alloc_inode), bg_bh);
 629
 630         status = ocfs2_block_group_fill(handle, alloc_inode, bg_bh,
 631                                         bg_blkno, num_bits, alloc_rec, cl);
 632         if (status < 0) {
 633                 mlog_errno(status);
 634                 goto bail;
 635         }
 636
 637         status = ocfs2_block_group_grow_discontig(handle, alloc_inode,
 638                                                   bg_bh, ac, cl, min_bits);
 639         if (status)
 640                 mlog_errno(status);
 641
 642 bail:
 643         if (status)
 644                 ocfs2_bg_alloc_cleanup(handle, ac, alloc_inode, bg_bh);
 645         return status ? ERR_PTR(status) : bg_bh;
 646 }
 647
 648 /*
 649  * We expect the block group allocator to already be locked.
 650  */
 651 static int ocfs2_block_group_alloc(struct ocfs2_super *osb,
 652                                    struct inode *alloc_inode,
 653                                    struct buffer_head *bh,
 654                                    u64 max_block,
 655                                    u64 *last_alloc_group,
 656                                    int flags)
 657 {
 658         int status, credits;
 659         struct ocfs2_dinode *fe = (struct ocfs2_dinode *) bh->b_data;
 660         struct ocfs2_chain_list *cl;
 661         struct ocfs2_alloc_context *ac = NULL;
 662         handle_t *handle = NULL;
 663         u16 alloc_rec;
 664         struct buffer_head *bg_bh = NULL;
 665         struct ocfs2_group_desc *bg;
 666
 667         BUG_ON(ocfs2_is_cluster_bitmap(alloc_inode));
 668
 669         cl = &fe->id2.i_chain;
 670         status = ocfs2_reserve_clusters_with_limit(osb,
 671                                                    le16_to_cpu(cl->cl_cpg),
 672                                                    max_block, flags, &ac);
 673         if (status < 0) {
 674                 if (status != -ENOSPC)
 675                         mlog_errno(status);
 676                 goto bail;
 677         }
 678
 679         credits = ocfs2_calc_group_alloc_credits(osb->sb,
 680                                                  le16_to_cpu(cl->cl_cpg));
 681         handle = ocfs2_start_trans(osb, credits);
 682         if (IS_ERR(handle)) {
 683                 status = PTR_ERR(handle);
 684                 handle = NULL;
 685                 mlog_errno(status);
 686                 goto bail;
 687         }
 688
 689         if (last_alloc_group && *last_alloc_group != 0) {
 690                 trace_ocfs2_block_group_alloc(
 691                                 (unsigned long long)*last_alloc_group);
 692                 ac->ac_last_group = *last_alloc_group;
 693         }
 694
 695         bg_bh = ocfs2_block_group_alloc_contig(osb, handle, alloc_inode,
 696                                                ac, cl);
 697         if (PTR_ERR(bg_bh) == -ENOSPC)
 698                 bg_bh = ocfs2_block_group_alloc_discontig(handle,
 699                                                           alloc_inode,
 700                                                           ac, cl);
 701         if (IS_ERR(bg_bh)) {
 702                 status = PTR_ERR(bg_bh);
 703                 bg_bh = NULL;
 704                 if (status != -ENOSPC)
 705                         mlog_errno(status);
 706                 goto bail;
 707         }
 708         bg = (struct ocfs2_group_desc *) bg_bh->b_data;
 709
 710         status = ocfs2_journal_access_di(handle, INODE_CACHE(alloc_inode),
 711                                          bh, OCFS2_JOURNAL_ACCESS_WRITE);
 712         if (status < 0) {
 713                 mlog_errno(status);
 714                 goto bail;
 715         }
 716
 717         alloc_rec = le16_to_cpu(bg->bg_chain);
 718         le32_add_cpu(&cl->cl_recs[alloc_rec].c_free,
 719                      le16_to_cpu(bg->bg_free_bits_count));
 720         le32_add_cpu(&cl->cl_recs[alloc_rec].c_total,
 721                      le16_to_cpu(bg->bg_bits));
 722         cl->cl_recs[alloc_rec].c_blkno = bg->bg_blkno;
 723         if (le16_to_cpu(cl->cl_next_free_rec) < le16_to_cpu(cl->cl_count))
 724                 le16_add_cpu(&cl->cl_next_free_rec, 1);
 725
 726         le32_add_cpu(&fe->id1.bitmap1.i_used, le16_to_cpu(bg->bg_bits) -
 727                                         le16_to_cpu(bg->bg_free_bits_count));
 728         le32_add_cpu(&fe->id1.bitmap1.i_total, le16_to_cpu(bg->bg_bits));
 729         le32_add_cpu(&fe->i_clusters, le16_to_cpu(cl->cl_cpg));
 730
 731         ocfs2_journal_dirty(handle, bh);
 732
 733         spin_lock(&OCFS2_I(alloc_inode)->ip_lock);
 734         OCFS2_I(alloc_inode)->ip_clusters = le32_to_cpu(fe->i_clusters);
 735         fe->i_size = cpu_to_le64(ocfs2_clusters_to_bytes(alloc_inode->i_sb,
 736                                              le32_to_cpu(fe->i_clusters)));
 737         spin_unlock(&OCFS2_I(alloc_inode)->ip_lock);
 738         i_size_write(alloc_inode, le64_to_cpu(fe->i_size));
 739         alloc_inode->i_blocks = ocfs2_inode_sector_count(alloc_inode);
 740         ocfs2_update_inode_fsync_trans(handle, alloc_inode, 0);
 741
 742         status = 0;
 743
 744         /* save the new last alloc group so that the caller can cache it. */
 745         if (last_alloc_group)
 746                 *last_alloc_group = ac->ac_last_group;
 747
 748 bail:
 749         if (handle)
 750                 ocfs2_commit_trans(osb, handle);
 751
 752         if (ac)
 753                 ocfs2_free_alloc_context(ac);
 754
 755         brelse(bg_bh);
 756
 757         if (status)
 758                 mlog_errno(status);
 759         return status;
 760 }
 761
 762 static int ocfs2_reserve_suballoc_bits(struct ocfs2_super *osb,
 763                                        struct ocfs2_alloc_context *ac,
 764                                        int type,
 765                                        u32 slot,
 766                                        u64 *last_alloc_group,
 767                                        int flags)
 768 {
 769         int status;
 770         u32 bits_wanted = ac->ac_bits_wanted;
 771         struct inode *alloc_inode;
 772         struct buffer_head *bh = NULL;
 773         struct ocfs2_dinode *fe;
 774         u32 free_bits;
 775
 776         alloc_inode = ocfs2_get_system_file_inode(osb, type, slot);
 777         if (!alloc_inode) {
 778                 mlog_errno(-EINVAL);
 779                 return -EINVAL;
 780         }
 781
 782         inode_lock(alloc_inode);
 783
 784         status = ocfs2_inode_lock(alloc_inode, &bh, 1);
 785         if (status < 0) {
 786                 inode_unlock(alloc_inode);
 787                 iput(alloc_inode);
 788
 789                 mlog_errno(status);
 790                 return status;
 791         }
 792
 793         ac->ac_inode = alloc_inode;
 794         ac->ac_alloc_slot = slot;
 795
 796         fe = (struct ocfs2_dinode *) bh->b_data;
 797
 798         /* The bh was validated by the inode read inside
 799          * ocfs2_inode_lock().  Any corruption is a code bug. */
 800         BUG_ON(!OCFS2_IS_VALID_DINODE(fe));
 801
 802         if (!(fe->i_flags & cpu_to_le32(OCFS2_CHAIN_FL))) {
 803                 status = ocfs2_error(alloc_inode->i_sb,
 804                                      "Invalid chain allocator %llu\n",
 805                                      (unsigned long long)le64_to_cpu(fe->i_blkno));
 806                 goto bail;
 807         }
 808
 809         free_bits = le32_to_cpu(fe->id1.bitmap1.i_total) -
 810                 le32_to_cpu(fe->id1.bitmap1.i_used);
 811
 812         if (bits_wanted > free_bits) {
 813                 /* cluster bitmap never grows */
 814                 if (ocfs2_is_cluster_bitmap(alloc_inode)) {
 815                         trace_ocfs2_reserve_suballoc_bits_nospc(bits_wanted,
 816                                                                 free_bits);
 817                         status = -ENOSPC;
 818                         goto bail;
 819                 }
 820
 821                 if (!(flags & ALLOC_NEW_GROUP)) {
 822                         trace_ocfs2_reserve_suballoc_bits_no_new_group(
 823                                                 slot, bits_wanted, free_bits);
 824                         status = -ENOSPC;
 825                         goto bail;
 826                 }
 827
 828                 status = ocfs2_block_group_alloc(osb, alloc_inode, bh,
 829                                                  ac->ac_max_block,
 830                                                  last_alloc_group, flags);
 831                 if (status < 0) {
 832                         if (status != -ENOSPC)
 833                                 mlog_errno(status);
 834                         goto bail;
 835                 }
 836                 atomic_inc(&osb->alloc_stats.bg_extends);
 837
 838                 /* You should never ask for this much metadata */
 839                 BUG_ON(bits_wanted >
 840                        (le32_to_cpu(fe->id1.bitmap1.i_total)
 841                         - le32_to_cpu(fe->id1.bitmap1.i_used)));
 842         }
 843
 844         get_bh(bh);
 845         ac->ac_bh = bh;
 846 bail:
 847         brelse(bh);
 848
 849         if (status)
 850                 mlog_errno(status);
 851         return status;
 852 }
 853
 854 static void ocfs2_init_inode_steal_slot(struct ocfs2_super *osb)
 855 {
 856         spin_lock(&osb->osb_lock);
 857         osb->s_inode_steal_slot = OCFS2_INVALID_SLOT;
 858         spin_unlock(&osb->osb_lock);
 859         atomic_set(&osb->s_num_inodes_stolen, 0);
 860 }
 861
 862 static void ocfs2_init_meta_steal_slot(struct ocfs2_super *osb)
 863 {
 864         spin_lock(&osb->osb_lock);
 865         osb->s_meta_steal_slot = OCFS2_INVALID_SLOT;
 866         spin_unlock(&osb->osb_lock);
 867         atomic_set(&osb->s_num_meta_stolen, 0);
 868 }
 869
 870 void ocfs2_init_steal_slots(struct ocfs2_super *osb)
 871 {
 872         ocfs2_init_inode_steal_slot(osb);
 873         ocfs2_init_meta_steal_slot(osb);
 874 }
 875
 876 static void __ocfs2_set_steal_slot(struct ocfs2_super *osb, int slot, int type)
 877 {
 878         spin_lock(&osb->osb_lock);
 879         if (type == INODE_ALLOC_SYSTEM_INODE)
 880                 osb->s_inode_steal_slot = (u16)slot;
 881         else if (type == EXTENT_ALLOC_SYSTEM_INODE)
 882                 osb->s_meta_steal_slot = (u16)slot;
 883         spin_unlock(&osb->osb_lock);
 884 }
 885
 886 static int __ocfs2_get_steal_slot(struct ocfs2_super *osb, int type)
 887 {
 888         int slot = OCFS2_INVALID_SLOT;
 889
 890         spin_lock(&osb->osb_lock);
 891         if (type == INODE_ALLOC_SYSTEM_INODE)
 892                 slot = osb->s_inode_steal_slot;
 893         else if (type == EXTENT_ALLOC_SYSTEM_INODE)
 894                 slot = osb->s_meta_steal_slot;
 895         spin_unlock(&osb->osb_lock);
 896
 897         return slot;
 898 }
 899
 900 static int ocfs2_get_inode_steal_slot(struct ocfs2_super *osb)
 901 {
 902         return __ocfs2_get_steal_slot(osb, INODE_ALLOC_SYSTEM_INODE);
 903 }
 904
 905 static int ocfs2_get_meta_steal_slot(struct ocfs2_super *osb)
 906 {
 907         return __ocfs2_get_steal_slot(osb, EXTENT_ALLOC_SYSTEM_INODE);
 908 }
 909
 910 static int ocfs2_steal_resource(struct ocfs2_super *osb,
 911                                 struct ocfs2_alloc_context *ac,
 912                                 int type)
 913 {
 914         int i, status = -ENOSPC;
 915         int slot = __ocfs2_get_steal_slot(osb, type);
 916
 917         /* Start to steal resource from the first slot after ours. */
 918         if (slot == OCFS2_INVALID_SLOT)
 919                 slot = osb->slot_num + 1;
 920
 921         for (i = 0; i < osb->max_slots; i++, slot++) {
 922                 if (slot == osb->max_slots)
 923                         slot = 0;
 924
 925                 if (slot == osb->slot_num)
 926                         continue;
 927
 928                 status = ocfs2_reserve_suballoc_bits(osb, ac,
 929                                                      type,
 930                                                      (u32)slot, NULL,
 931                                                      NOT_ALLOC_NEW_GROUP);
 932                 if (status >= 0) {
 933                         __ocfs2_set_steal_slot(osb, slot, type);
 934                         break;
 935                 }
 936
 937                 ocfs2_free_ac_resource(ac);
 938         }
 939
 940         return status;
 941 }
 942
 943 static int ocfs2_steal_inode(struct ocfs2_super *osb,
 944                              struct ocfs2_alloc_context *ac)
 945 {
 946         return ocfs2_steal_resource(osb, ac, INODE_ALLOC_SYSTEM_INODE);
 947 }
 948
 949 static int ocfs2_steal_meta(struct ocfs2_super *osb,
 950                             struct ocfs2_alloc_context *ac)
 951 {
 952         return ocfs2_steal_resource(osb, ac, EXTENT_ALLOC_SYSTEM_INODE);
 953 }
 954
 955 int ocfs2_reserve_new_metadata_blocks(struct ocfs2_super *osb,
 956                                       int blocks,
 957                                       struct ocfs2_alloc_context **ac)
 958 {
 959         int status;
 960         int slot = ocfs2_get_meta_steal_slot(osb);
 961
 962         *ac = kzalloc(sizeof(struct ocfs2_alloc_context), GFP_KERNEL);
 963         if (!(*ac)) {
 964                 status = -ENOMEM;
 965                 mlog_errno(status);
 966                 goto bail;
 967         }
 968
 969         (*ac)->ac_bits_wanted = blocks;
 970         (*ac)->ac_which = OCFS2_AC_USE_META;
 971         (*ac)->ac_group_search = ocfs2_block_group_search;
 972
 973         if (slot != OCFS2_INVALID_SLOT &&
 974                 atomic_read(&osb->s_num_meta_stolen) < OCFS2_MAX_TO_STEAL)
 975                 goto extent_steal;
 976
 977         atomic_set(&osb->s_num_meta_stolen, 0);
 978         status = ocfs2_reserve_suballoc_bits(osb, (*ac),
 979                                              EXTENT_ALLOC_SYSTEM_INODE,
 980                                              (u32)osb->slot_num, NULL,
 981                                              ALLOC_GROUPS_FROM_GLOBAL|ALLOC_NEW_GROUP);
 982
 983
 984         if (status >= 0) {
 985                 status = 0;
 986                 if (slot != OCFS2_INVALID_SLOT)
 987                         ocfs2_init_meta_steal_slot(osb);
 988                 goto bail;
 989         } else if (status < 0 && status != -ENOSPC) {
 990                 mlog_errno(status);
 991                 goto bail;
 992         }
 993
 994         ocfs2_free_ac_resource(*ac);
 995
 996 extent_steal:
 997         status = ocfs2_steal_meta(osb, *ac);
 998         atomic_inc(&osb->s_num_meta_stolen);
 999         if (status < 0) {
1000                 if (status != -ENOSPC)
1001                         mlog_errno(status);
1002                 goto bail;
1003         }
1004
1005         status = 0;
1006 bail:
1007         if ((status < 0) && *ac) {
1008                 ocfs2_free_alloc_context(*ac);
1009                 *ac = NULL;
1010         }
1011
1012         if (status)
1013                 mlog_errno(status);
1014         return status;
1015 }
1016
1017 int ocfs2_reserve_new_metadata(struct ocfs2_super *osb,
1018                                struct ocfs2_extent_list *root_el,
1019                                struct ocfs2_alloc_context **ac)
1020 {
1021         return ocfs2_reserve_new_metadata_blocks(osb,
1022                                         ocfs2_extend_meta_needed(root_el),
1023                                         ac);
1024 }
1025
1026 int ocfs2_reserve_new_inode(struct ocfs2_super *osb,
1027                             struct ocfs2_alloc_context **ac)
1028 {
1029         int status;
1030         int slot = ocfs2_get_inode_steal_slot(osb);
1031         u64 alloc_group;
1032
1033         *ac = kzalloc(sizeof(struct ocfs2_alloc_context), GFP_KERNEL);
1034         if (!(*ac)) {
1035                 status = -ENOMEM;
1036                 mlog_errno(status);
1037                 goto bail;
1038         }
1039
1040         (*ac)->ac_bits_wanted = 1;
1041         (*ac)->ac_which = OCFS2_AC_USE_INODE;
1042
1043         (*ac)->ac_group_search = ocfs2_block_group_search;
1044
1045         /*
1046          * stat(2) can't handle i_ino > 32bits, so we tell the
1047          * lower levels not to allocate us a block group past that
1048          * limit.  The 'inode64' mount option avoids this behavior.
1049          */
1050         if (!(osb->s_mount_opt & OCFS2_MOUNT_INODE64))
1051                 (*ac)->ac_max_block = (u32)~0U;
1052
1053         /*
1054          * slot is set when we successfully steal inode from other nodes.
1055          * It is reset in 3 places:
1056          * 1. when we flush the truncate log
1057          * 2. when we complete local alloc recovery.
1058          * 3. when we successfully allocate from our own slot.
1059          * After it is set, we will go on stealing inodes until we find the
1060          * need to check our slots to see whether there is some space for us.
1061          */
1062         if (slot != OCFS2_INVALID_SLOT &&
1063             atomic_read(&osb->s_num_inodes_stolen) < OCFS2_MAX_TO_STEAL)
1064                 goto inode_steal;
1065
1066         atomic_set(&osb->s_num_inodes_stolen, 0);
1067         alloc_group = osb->osb_inode_alloc_group;
1068         status = ocfs2_reserve_suballoc_bits(osb, *ac,
1069                                              INODE_ALLOC_SYSTEM_INODE,
1070                                              (u32)osb->slot_num,
1071                                              &alloc_group,
1072                                              ALLOC_NEW_GROUP |
1073                                              ALLOC_GROUPS_FROM_GLOBAL);
1074         if (status >= 0) {
1075                 status = 0;
1076
1077                 spin_lock(&osb->osb_lock);
1078                 osb->osb_inode_alloc_group = alloc_group;
1079                 spin_unlock(&osb->osb_lock);
1080                 trace_ocfs2_reserve_new_inode_new_group(
1081                         (unsigned long long)alloc_group);
1082
1083                 /*
1084                  * Some inodes must be freed by us, so try to allocate
1085                  * from our own next time.
1086                  */
1087                 if (slot != OCFS2_INVALID_SLOT)
1088                         ocfs2_init_inode_steal_slot(osb);
1089                 goto bail;
1090         } else if (status < 0 && status != -ENOSPC) {
1091                 mlog_errno(status);
1092                 goto bail;
1093         }
1094
1095         ocfs2_free_ac_resource(*ac);
1096
1097 inode_steal:
1098         status = ocfs2_steal_inode(osb, *ac);
1099         atomic_inc(&osb->s_num_inodes_stolen);
1100         if (status < 0) {
1101                 if (status != -ENOSPC)
1102                         mlog_errno(status);
1103                 goto bail;
1104         }
1105
1106         status = 0;
1107 bail:
1108         if ((status < 0) && *ac) {
1109                 ocfs2_free_alloc_context(*ac);
1110                 *ac = NULL;
1111         }
1112
1113         if (status)
1114                 mlog_errno(status);
1115         return status;
1116 }
1117
1118 /* local alloc code has to do the same thing, so rather than do this
1119  * twice.. */
1120 int ocfs2_reserve_cluster_bitmap_bits(struct ocfs2_super *osb,
1121                                       struct ocfs2_alloc_context *ac)
1122 {
1123         int status;
1124
1125         ac->ac_which = OCFS2_AC_USE_MAIN;
1126         ac->ac_group_search = ocfs2_cluster_group_search;
1127
1128         status = ocfs2_reserve_suballoc_bits(osb, ac,
1129                                              GLOBAL_BITMAP_SYSTEM_INODE,
1130                                              OCFS2_INVALID_SLOT, NULL,
1131                                              ALLOC_NEW_GROUP);
1132         if (status < 0 && status != -ENOSPC)
1133                 mlog_errno(status);
1134
1135         return status;
1136 }
1137
1138 /* Callers don't need to care which bitmap (local alloc or main) to
1139  * use so we figure it out for them, but unfortunately this clutters
1140  * things a bit. */
1141 static int ocfs2_reserve_clusters_with_limit(struct ocfs2_super *osb,
1142                                              u32 bits_wanted, u64 max_block,
1143                                              int flags,
1144                                              struct ocfs2_alloc_context **ac)
1145 {
1146         int status, ret = 0;
1147         int retried = 0;
1148
1149         *ac = kzalloc(sizeof(struct ocfs2_alloc_context), GFP_KERNEL);
1150         if (!(*ac)) {
1151                 status = -ENOMEM;
1152                 mlog_errno(status);
1153                 goto bail;
1154         }
1155
1156         (*ac)->ac_bits_wanted = bits_wanted;
1157         (*ac)->ac_max_block = max_block;
1158
1159         status = -ENOSPC;
1160         if (!(flags & ALLOC_GROUPS_FROM_GLOBAL) &&
1161             ocfs2_alloc_should_use_local(osb, bits_wanted)) {
1162                 status = ocfs2_reserve_local_alloc_bits(osb,
1163                                                         bits_wanted,
1164                                                         *ac);
1165                 if ((status < 0) && (status != -ENOSPC)) {
1166                         mlog_errno(status);
1167                         goto bail;
1168                 }
1169         }
1170
1171         if (status == -ENOSPC) {
1172 retry:
1173                 status = ocfs2_reserve_cluster_bitmap_bits(osb, *ac);
1174                 /* Retry if there is sufficient space cached in truncate log */
1175                 if (status == -ENOSPC && !retried) {
1176                         retried = 1;
1177                         ocfs2_inode_unlock((*ac)->ac_inode, 1);
1178                         inode_unlock((*ac)->ac_inode);
1179
1180                         ret = ocfs2_try_to_free_truncate_log(osb, bits_wanted);
1181                         if (ret == 1) {
1182                                 iput((*ac)->ac_inode);
1183                                 (*ac)->ac_inode = NULL;
1184                                 goto retry;
1185                         }
1186
1187                         if (ret < 0)
1188                                 mlog_errno(ret);
1189
1190                         inode_lock((*ac)->ac_inode);
1191                         ret = ocfs2_inode_lock((*ac)->ac_inode, NULL, 1);
1192                         if (ret < 0) {
1193                                 mlog_errno(ret);
1194                                 inode_unlock((*ac)->ac_inode);
1195                                 iput((*ac)->ac_inode);
1196                                 (*ac)->ac_inode = NULL;
1197                                 goto bail;
1198                         }
1199                 }
1200                 if (status < 0) {
1201                         if (status != -ENOSPC)
1202                                 mlog_errno(status);
1203                         goto bail;
1204                 }
1205         }
1206
1207         status = 0;
1208 bail:
1209         if ((status < 0) && *ac) {
1210                 ocfs2_free_alloc_context(*ac);
1211                 *ac = NULL;
1212         }
1213
1214         if (status)
1215                 mlog_errno(status);
1216         return status;
1217 }
1218
1219 int ocfs2_reserve_clusters(struct ocfs2_super *osb,
1220                            u32 bits_wanted,
1221                            struct ocfs2_alloc_context **ac)
1222 {
1223         return ocfs2_reserve_clusters_with_limit(osb, bits_wanted, 0,
1224                                                  ALLOC_NEW_GROUP, ac);
1225 }
1226
1227 /*
1228  * More or less lifted from ext3. I'll leave their description below:
1229  *
1230  * "For ext3 allocations, we must not reuse any blocks which are
1231  * allocated in the bitmap buffer's "last committed data" copy.  This
1232  * prevents deletes from freeing up the page for reuse until we have
1233  * committed the delete transaction.
1234  *
1235  * If we didn't do this, then deleting something and reallocating it as
1236  * data would allow the old block to be overwritten before the
1237  * transaction committed (because we force data to disk before commit).
1238  * This would lead to corruption if we crashed between overwriting the
1239  * data and committing the delete.
1240  *
1241  * @@@ We may want to make this allocation behaviour conditional on
1242  * data-writes at some point, and disable it for metadata allocations or
1243  * sync-data inodes."
1244  *
1245  * Note: OCFS2 already does this differently for metadata vs data
1246  * allocations, as those bitmaps are separate and undo access is never
1247  * called on a metadata group descriptor.
1248  */
1249 static int ocfs2_test_bg_bit_allocatable(struct buffer_head *bg_bh,
1250                                          int nr)
1251 {
1252         struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
1253         struct journal_head *jh;
1254         int ret;
1255
1256         if (ocfs2_test_bit(nr, (unsigned long *)bg->bg_bitmap))
1257                 return 0;
1258
1259         jh = jbd2_journal_grab_journal_head(bg_bh);
1260         if (!jh)
1261                 return 1;
1262
1263         spin_lock(&jh->b_state_lock);
1264         bg = (struct ocfs2_group_desc *) jh->b_committed_data;
1265         if (bg)
1266                 ret = !ocfs2_test_bit(nr, (unsigned long *)bg->bg_bitmap);
1267         else
1268                 ret = 1;
1269         spin_unlock(&jh->b_state_lock);
1270         jbd2_journal_put_journal_head(jh);
1271
1272         return ret;
1273 }
1274
1275 static int ocfs2_block_group_find_clear_bits(struct ocfs2_super *osb,
1276                                              struct buffer_head *bg_bh,
1277                                              unsigned int bits_wanted,
1278                                              unsigned int total_bits,
1279                                              struct ocfs2_suballoc_result *res)
1280 {
1281         void *bitmap;
1282         u16 best_offset, best_size;
1283         int offset, start, found, status = 0;
1284         struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
1285
1286         /* Callers got this descriptor from
1287          * ocfs2_read_group_descriptor().  Any corruption is a code bug. */
1288         BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
1289
1290         found = start = best_offset = best_size = 0;
1291         bitmap = bg->bg_bitmap;
1292
1293         while((offset = ocfs2_find_next_zero_bit(bitmap, total_bits, start)) != -1) {
1294                 if (offset == total_bits)
1295                         break;
1296
1297                 if (!ocfs2_test_bg_bit_allocatable(bg_bh, offset)) {
1298                         /* We found a zero, but we can't use it as it
1299                          * hasn't been put to disk yet! */
1300                         found = 0;
1301                         start = offset + 1;
1302                 } else if (offset == start) {
1303                         /* we found a zero */
1304                         found++;
1305                         /* move start to the next bit to test */
1306                         start++;
1307                 } else {
1308                         /* got a zero after some ones */
1309                         found = 1;
1310                         start = offset + 1;
1311                 }
1312                 if (found > best_size) {
1313                         best_size = found;
1314                         best_offset = start - found;
1315                 }
1316                 /* we got everything we needed */
1317                 if (found == bits_wanted) {
1318                         /* mlog(0, "Found it all!\n"); */
1319                         break;
1320                 }
1321         }
1322
1323         if (best_size) {
1324                 res->sr_bit_offset = best_offset;
1325                 res->sr_bits = best_size;
1326         } else {
1327                 status = -ENOSPC;
1328                 /* No error log here -- see the comment above
1329                  * ocfs2_test_bg_bit_allocatable */
1330         }
1331
1332         return status;
1333 }
1334
1335 int ocfs2_block_group_set_bits(handle_t *handle,
1336                                              struct inode *alloc_inode,
1337                                              struct ocfs2_group_desc *bg,
1338                                              struct buffer_head *group_bh,
1339                                              unsigned int bit_off,
1340                                              unsigned int num_bits)
1341 {
1342         int status;
1343         void *bitmap = bg->bg_bitmap;
1344         int journal_type = OCFS2_JOURNAL_ACCESS_WRITE;
1345
1346         /* All callers get the descriptor via
1347          * ocfs2_read_group_descriptor().  Any corruption is a code bug. */
1348         BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
1349         BUG_ON(le16_to_cpu(bg->bg_free_bits_count) < num_bits);
1350
1351         trace_ocfs2_block_group_set_bits(bit_off, num_bits);
1352
1353         if (ocfs2_is_cluster_bitmap(alloc_inode))
1354                 journal_type = OCFS2_JOURNAL_ACCESS_UNDO;
1355
1356         status = ocfs2_journal_access_gd(handle,
1357                                          INODE_CACHE(alloc_inode),
1358                                          group_bh,
1359                                          journal_type);
1360         if (status < 0) {
1361                 mlog_errno(status);
1362                 goto bail;
1363         }
1364
1365         le16_add_cpu(&bg->bg_free_bits_count, -num_bits);
1366         if (le16_to_cpu(bg->bg_free_bits_count) > le16_to_cpu(bg->bg_bits)) {
1367                 return ocfs2_error(alloc_inode->i_sb, "Group descriptor # %llu has bit count %u but claims %u are freed. num_bits %d\n",
1368                                    (unsigned long long)le64_to_cpu(bg->bg_blkno),
1369                                    le16_to_cpu(bg->bg_bits),
1370                                    le16_to_cpu(bg->bg_free_bits_count),
1371                                    num_bits);
1372         }
1373         while(num_bits--)
1374                 ocfs2_set_bit(bit_off++, bitmap);
1375
1376         ocfs2_journal_dirty(handle, group_bh);
1377
1378 bail:
1379         return status;
1380 }
1381
1382 /* find the one with the most empty bits */
1383 static inline u16 ocfs2_find_victim_chain(struct ocfs2_chain_list *cl)
1384 {
1385         u16 curr, best;
1386
1387         BUG_ON(!cl->cl_next_free_rec);
1388
1389         best = curr = 0;
1390         while (curr < le16_to_cpu(cl->cl_next_free_rec)) {
1391                 if (le32_to_cpu(cl->cl_recs[curr].c_free) >
1392                     le32_to_cpu(cl->cl_recs[best].c_free))
1393                         best = curr;
1394                 curr++;
1395         }
1396
1397         BUG_ON(best >= le16_to_cpu(cl->cl_next_free_rec));
1398         return best;
1399 }
1400
1401 static int ocfs2_relink_block_group(handle_t *handle,
1402                                     struct inode *alloc_inode,
1403                                     struct buffer_head *fe_bh,
1404                                     struct buffer_head *bg_bh,
1405                                     struct buffer_head *prev_bg_bh,
1406                                     u16 chain)
1407 {
1408         int status;
1409         /* there is a really tiny chance the journal calls could fail,
1410          * but we wouldn't want inconsistent blocks in *any* case. */
1411         u64 bg_ptr, prev_bg_ptr;
1412         struct ocfs2_dinode *fe = (struct ocfs2_dinode *) fe_bh->b_data;
1413         struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
1414         struct ocfs2_group_desc *prev_bg = (struct ocfs2_group_desc *) prev_bg_bh->b_data;
1415
1416         /* The caller got these descriptors from
1417          * ocfs2_read_group_descriptor().  Any corruption is a code bug. */
1418         BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
1419         BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(prev_bg));
1420
1421         trace_ocfs2_relink_block_group(
1422                 (unsigned long long)le64_to_cpu(fe->i_blkno), chain,
1423                 (unsigned long long)le64_to_cpu(bg->bg_blkno),
1424                 (unsigned long long)le64_to_cpu(prev_bg->bg_blkno));
1425
1426         bg_ptr = le64_to_cpu(bg->bg_next_group);
1427         prev_bg_ptr = le64_to_cpu(prev_bg->bg_next_group);
1428
1429         status = ocfs2_journal_access_gd(handle, INODE_CACHE(alloc_inode),
1430                                          prev_bg_bh,
1431                                          OCFS2_JOURNAL_ACCESS_WRITE);
1432         if (status < 0)
1433                 goto out;
1434
1435         prev_bg->bg_next_group = bg->bg_next_group;
1436         ocfs2_journal_dirty(handle, prev_bg_bh);
1437
1438         status = ocfs2_journal_access_gd(handle, INODE_CACHE(alloc_inode),
1439                                          bg_bh, OCFS2_JOURNAL_ACCESS_WRITE);
1440         if (status < 0)
1441                 goto out_rollback_prev_bg;
1442
1443         bg->bg_next_group = fe->id2.i_chain.cl_recs[chain].c_blkno;
1444         ocfs2_journal_dirty(handle, bg_bh);
1445
1446         status = ocfs2_journal_access_di(handle, INODE_CACHE(alloc_inode),
1447                                          fe_bh, OCFS2_JOURNAL_ACCESS_WRITE);
1448         if (status < 0)
1449                 goto out_rollback_bg;
1450
1451         fe->id2.i_chain.cl_recs[chain].c_blkno = bg->bg_blkno;
1452         ocfs2_journal_dirty(handle, fe_bh);
1453
1454 out:
1455         if (status < 0)
1456                 mlog_errno(status);
1457         return status;
1458
1459 out_rollback_bg:
1460         bg->bg_next_group = cpu_to_le64(bg_ptr);
1461 out_rollback_prev_bg:
1462         prev_bg->bg_next_group = cpu_to_le64(prev_bg_ptr);
1463         goto out;
1464 }
1465
1466 static inline int ocfs2_block_group_reasonably_empty(struct ocfs2_group_desc *bg,
1467                                                      u32 wanted)
1468 {
1469         return le16_to_cpu(bg->bg_free_bits_count) > wanted;
1470 }
1471
1472 /* return 0 on success, -ENOSPC to keep searching and any other < 0
1473  * value on error. */
1474 static int ocfs2_cluster_group_search(struct inode *inode,
1475                                       struct buffer_head *group_bh,
1476                                       u32 bits_wanted, u32 min_bits,
1477                                       u64 max_block,
1478                                       struct ocfs2_suballoc_result *res)
1479 {
1480         int search = -ENOSPC;
1481         int ret;
1482         u64 blkoff;
1483         struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *) group_bh->b_data;
1484         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1485         unsigned int max_bits, gd_cluster_off;
1486
1487         BUG_ON(!ocfs2_is_cluster_bitmap(inode));
1488
1489         if (gd->bg_free_bits_count) {
1490                 max_bits = le16_to_cpu(gd->bg_bits);
1491
1492                 /* Tail groups in cluster bitmaps which aren't cpg
1493                  * aligned are prone to partial extension by a failed
1494                  * fs resize. If the file system resize never got to
1495                  * update the dinode cluster count, then we don't want
1496                  * to trust any clusters past it, regardless of what
1497                  * the group descriptor says. */
1498                 gd_cluster_off = ocfs2_blocks_to_clusters(inode->i_sb,
1499                                                           le64_to_cpu(gd->bg_blkno));
1500                 if ((gd_cluster_off + max_bits) >
1501                     OCFS2_I(inode)->ip_clusters) {
1502                         max_bits = OCFS2_I(inode)->ip_clusters - gd_cluster_off;
1503                         trace_ocfs2_cluster_group_search_wrong_max_bits(
1504                                 (unsigned long long)le64_to_cpu(gd->bg_blkno),
1505                                 le16_to_cpu(gd->bg_bits),
1506                                 OCFS2_I(inode)->ip_clusters, max_bits);
1507                 }
1508
1509                 ret = ocfs2_block_group_find_clear_bits(osb,
1510                                                         group_bh, bits_wanted,
1511                                                         max_bits, res);
1512                 if (ret)
1513                         return ret;
1514
1515                 if (max_block) {
1516                         blkoff = ocfs2_clusters_to_blocks(inode->i_sb,
1517                                                           gd_cluster_off +
1518                                                           res->sr_bit_offset +
1519                                                           res->sr_bits);
1520                         trace_ocfs2_cluster_group_search_max_block(
1521                                 (unsigned long long)blkoff,
1522                                 (unsigned long long)max_block);
1523                         if (blkoff > max_block)
1524                                 return -ENOSPC;
1525                 }
1526
1527                 /* ocfs2_block_group_find_clear_bits() might
1528                  * return success, but we still want to return
1529                  * -ENOSPC unless it found the minimum number
1530                  * of bits. */
1531                 if (min_bits <= res->sr_bits)
1532                         search = 0; /* success */
1533                 else if (res->sr_bits) {
1534                         /*
1535                          * Don't show bits which we'll be returning
1536                          * for allocation to the local alloc bitmap.
1537                          */
1538                         ocfs2_local_alloc_seen_free_bits(osb, res->sr_bits);
1539                 }
1540         }
1541
1542         return search;
1543 }
1544
1545 static int ocfs2_block_group_search(struct inode *inode,
1546                                     struct buffer_head *group_bh,
1547                                     u32 bits_wanted, u32 min_bits,
1548                                     u64 max_block,
1549                                     struct ocfs2_suballoc_result *res)
1550 {
1551         int ret = -ENOSPC;
1552         u64 blkoff;
1553         struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) group_bh->b_data;
1554
1555         BUG_ON(min_bits != 1);
1556         BUG_ON(ocfs2_is_cluster_bitmap(inode));
1557
1558         if (bg->bg_free_bits_count) {
1559                 ret = ocfs2_block_group_find_clear_bits(OCFS2_SB(inode->i_sb),
1560                                                         group_bh, bits_wanted,
1561                                                         le16_to_cpu(bg->bg_bits),
1562                                                         res);
1563                 if (!ret && max_block) {
1564                         blkoff = le64_to_cpu(bg->bg_blkno) +
1565                                 res->sr_bit_offset + res->sr_bits;
1566                         trace_ocfs2_block_group_search_max_block(
1567                                 (unsigned long long)blkoff,
1568                                 (unsigned long long)max_block);
1569                         if (blkoff > max_block)
1570                                 ret = -ENOSPC;
1571                 }
1572         }
1573
1574         return ret;
1575 }
1576
1577 int ocfs2_alloc_dinode_update_counts(struct inode *inode,
1578                                        handle_t *handle,
1579                                        struct buffer_head *di_bh,
1580                                        u32 num_bits,
1581                                        u16 chain)
1582 {
1583         int ret;
1584         u32 tmp_used;
1585         struct ocfs2_dinode *di = (struct ocfs2_dinode *) di_bh->b_data;
1586         struct ocfs2_chain_list *cl = (struct ocfs2_chain_list *) &di->id2.i_chain;
1587
1588         ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
1589                                       OCFS2_JOURNAL_ACCESS_WRITE);
1590         if (ret < 0) {
1591                 mlog_errno(ret);
1592                 goto out;
1593         }
1594
1595         tmp_used = le32_to_cpu(di->id1.bitmap1.i_used);
1596         di->id1.bitmap1.i_used = cpu_to_le32(num_bits + tmp_used);
1597         le32_add_cpu(&cl->cl_recs[chain].c_free, -num_bits);
1598         ocfs2_journal_dirty(handle, di_bh);
1599
1600 out:
1601         return ret;
1602 }
1603
1604 void ocfs2_rollback_alloc_dinode_counts(struct inode *inode,
1605                                        struct buffer_head *di_bh,
1606                                        u32 num_bits,
1607                                        u16 chain)
1608 {
1609         u32 tmp_used;
1610         struct ocfs2_dinode *di = (struct ocfs2_dinode *) di_bh->b_data;
1611         struct ocfs2_chain_list *cl;
1612
1613         cl = (struct ocfs2_chain_list *)&di->id2.i_chain;
1614         tmp_used = le32_to_cpu(di->id1.bitmap1.i_used);
1615         di->id1.bitmap1.i_used = cpu_to_le32(tmp_used - num_bits);
1616         le32_add_cpu(&cl->cl_recs[chain].c_free, num_bits);
1617 }
1618
1619 static int ocfs2_bg_discontig_fix_by_rec(struct ocfs2_suballoc_result *res,
1620                                          struct ocfs2_extent_rec *rec,
1621                                          struct ocfs2_chain_list *cl)
1622 {
1623         unsigned int bpc = le16_to_cpu(cl->cl_bpc);
1624         unsigned int bitoff = le32_to_cpu(rec->e_cpos) * bpc;
1625         unsigned int bitcount = le16_to_cpu(rec->e_leaf_clusters) * bpc;
1626
1627         if (res->sr_bit_offset < bitoff)
1628                 return 0;
1629         if (res->sr_bit_offset >= (bitoff + bitcount))
1630                 return 0;
1631         res->sr_blkno = le64_to_cpu(rec->e_blkno) +
1632                 (res->sr_bit_offset - bitoff);
1633         if ((res->sr_bit_offset + res->sr_bits) > (bitoff + bitcount))
1634                 res->sr_bits = (bitoff + bitcount) - res->sr_bit_offset;
1635         return 1;
1636 }
1637
1638 static void ocfs2_bg_discontig_fix_result(struct ocfs2_alloc_context *ac,
1639                                           struct ocfs2_group_desc *bg,
1640                                           struct ocfs2_suballoc_result *res)
1641 {
1642         int i;
1643         u64 bg_blkno = res->sr_bg_blkno;  /* Save off */
1644         struct ocfs2_extent_rec *rec;
1645         struct ocfs2_dinode *di = (struct ocfs2_dinode *)ac->ac_bh->b_data;
1646         struct ocfs2_chain_list *cl = &di->id2.i_chain;
1647
1648         if (ocfs2_is_cluster_bitmap(ac->ac_inode)) {
1649                 res->sr_blkno = 0;
1650                 return;
1651         }
1652
1653         res->sr_blkno = res->sr_bg_blkno + res->sr_bit_offset;
1654         res->sr_bg_blkno = 0;  /* Clear it for contig block groups */
1655         if (!ocfs2_supports_discontig_bg(OCFS2_SB(ac->ac_inode->i_sb)) ||
1656             !bg->bg_list.l_next_free_rec)
1657                 return;
1658
1659         for (i = 0; i < le16_to_cpu(bg->bg_list.l_next_free_rec); i++) {
1660                 rec = &bg->bg_list.l_recs[i];
1661                 if (ocfs2_bg_discontig_fix_by_rec(res, rec, cl)) {
1662                         res->sr_bg_blkno = bg_blkno;  /* Restore */
1663                         break;
1664                 }
1665         }
1666 }
1667
1668 static int ocfs2_search_one_group(struct ocfs2_alloc_context *ac,
1669                                   handle_t *handle,
1670                                   u32 bits_wanted,
1671                                   u32 min_bits,
1672                                   struct ocfs2_suballoc_result *res,
1673                                   u16 *bits_left)
1674 {
1675         int ret;
1676         struct buffer_head *group_bh = NULL;
1677         struct ocfs2_group_desc *gd;
1678         struct ocfs2_dinode *di = (struct ocfs2_dinode *)ac->ac_bh->b_data;
1679         struct inode *alloc_inode = ac->ac_inode;
1680
1681         ret = ocfs2_read_group_descriptor(alloc_inode, di,
1682                                           res->sr_bg_blkno, &group_bh);
1683         if (ret < 0) {
1684                 mlog_errno(ret);
1685                 return ret;
1686         }
1687
1688         gd = (struct ocfs2_group_desc *) group_bh->b_data;
1689         ret = ac->ac_group_search(alloc_inode, group_bh, bits_wanted, min_bits,
1690                                   ac->ac_max_block, res);
1691         if (ret < 0) {
1692                 if (ret != -ENOSPC)
1693                         mlog_errno(ret);
1694                 goto out;
1695         }
1696
1697         if (!ret)
1698                 ocfs2_bg_discontig_fix_result(ac, gd, res);
1699
1700         /*
1701          * sr_bg_blkno might have been changed by
1702          * ocfs2_bg_discontig_fix_result
1703          */
1704         res->sr_bg_stable_blkno = group_bh->b_blocknr;
1705
1706         if (ac->ac_find_loc_only)
1707                 goto out_loc_only;
1708
1709         ret = ocfs2_alloc_dinode_update_counts(alloc_inode, handle, ac->ac_bh,
1710                                                res->sr_bits,
1711                                                le16_to_cpu(gd->bg_chain));
1712         if (ret < 0) {
1713                 mlog_errno(ret);
1714                 goto out;
1715         }
1716
1717         ret = ocfs2_block_group_set_bits(handle, alloc_inode, gd, group_bh,
1718                                          res->sr_bit_offset, res->sr_bits);
1719         if (ret < 0) {
1720                 ocfs2_rollback_alloc_dinode_counts(alloc_inode, ac->ac_bh,
1721                                                res->sr_bits,
1722                                                le16_to_cpu(gd->bg_chain));
1723                 mlog_errno(ret);
1724         }
1725
1726 out_loc_only:
1727         *bits_left = le16_to_cpu(gd->bg_free_bits_count);
1728
1729 out:
1730         brelse(group_bh);
1731
1732         return ret;
1733 }
1734
1735 static int ocfs2_search_chain(struct ocfs2_alloc_context *ac,
1736                               handle_t *handle,
1737                               u32 bits_wanted,
1738                               u32 min_bits,
1739                               struct ocfs2_suballoc_result *res,
1740                               u16 *bits_left)
1741 {
1742         int status;
1743         u16 chain;
1744         u64 next_group;
1745         struct inode *alloc_inode = ac->ac_inode;
1746         struct buffer_head *group_bh = NULL;
1747         struct buffer_head *prev_group_bh = NULL;
1748         struct ocfs2_dinode *fe = (struct ocfs2_dinode *) ac->ac_bh->b_data;
1749         struct ocfs2_chain_list *cl = (struct ocfs2_chain_list *) &fe->id2.i_chain;
1750         struct ocfs2_group_desc *bg;
1751
1752         chain = ac->ac_chain;
1753         trace_ocfs2_search_chain_begin(
1754                 (unsigned long long)OCFS2_I(alloc_inode)->ip_blkno,
1755                 bits_wanted, chain);
1756
1757         status = ocfs2_read_group_descriptor(alloc_inode, fe,
1758                                              le64_to_cpu(cl->cl_recs[chain].c_blkno),
1759                                              &group_bh);
1760         if (status < 0) {
1761                 mlog_errno(status);
1762                 goto bail;
1763         }
1764         bg = (struct ocfs2_group_desc *) group_bh->b_data;
1765
1766         status = -ENOSPC;
1767         /* for now, the chain search is a bit simplistic. We just use
1768          * the 1st group with any empty bits. */
1769         while ((status = ac->ac_group_search(alloc_inode, group_bh,
1770                                              bits_wanted, min_bits,
1771                                              ac->ac_max_block,
1772                                              res)) == -ENOSPC) {
1773                 if (!bg->bg_next_group)
1774                         break;
1775
1776                 brelse(prev_group_bh);
1777                 prev_group_bh = NULL;
1778
1779                 next_group = le64_to_cpu(bg->bg_next_group);
1780                 prev_group_bh = group_bh;
1781                 group_bh = NULL;
1782                 status = ocfs2_read_group_descriptor(alloc_inode, fe,
1783                                                      next_group, &group_bh);
1784                 if (status < 0) {
1785                         mlog_errno(status);
1786                         goto bail;
1787                 }
1788                 bg = (struct ocfs2_group_desc *) group_bh->b_data;
1789         }
1790         if (status < 0) {
1791                 if (status != -ENOSPC)
1792                         mlog_errno(status);
1793                 goto bail;
1794         }
1795
1796         trace_ocfs2_search_chain_succ(
1797                 (unsigned long long)le64_to_cpu(bg->bg_blkno), res->sr_bits);
1798
1799         res->sr_bg_blkno = le64_to_cpu(bg->bg_blkno);
1800
1801         BUG_ON(res->sr_bits == 0);
1802         if (!status)
1803                 ocfs2_bg_discontig_fix_result(ac, bg, res);
1804
1805         /*
1806          * sr_bg_blkno might have been changed by
1807          * ocfs2_bg_discontig_fix_result
1808          */
1809         res->sr_bg_stable_blkno = group_bh->b_blocknr;
1810
1811         /*
1812          * Keep track of previous block descriptor read. When
1813          * we find a target, if we have read more than X
1814          * number of descriptors, and the target is reasonably
1815          * empty, relink him to top of his chain.
1816          *
1817          * We've read 0 extra blocks and only send one more to
1818          * the transaction, yet the next guy to search has a
1819          * much easier time.
1820          *
1821          * Do this *after* figuring out how many bits we're taking out
1822          * of our target group.
1823          */
1824         if (!ac->ac_disable_chain_relink &&
1825             (prev_group_bh) &&
1826             (ocfs2_block_group_reasonably_empty(bg, res->sr_bits))) {
1827                 status = ocfs2_relink_block_group(handle, alloc_inode,
1828                                                   ac->ac_bh, group_bh,
1829                                                   prev_group_bh, chain);
1830                 if (status < 0) {
1831                         mlog_errno(status);
1832                         goto bail;
1833                 }
1834         }
1835
1836         if (ac->ac_find_loc_only)
1837                 goto out_loc_only;
1838
1839         status = ocfs2_alloc_dinode_update_counts(alloc_inode, handle,
1840                                                   ac->ac_bh, res->sr_bits,
1841                                                   chain);
1842         if (status) {
1843                 mlog_errno(status);
1844                 goto bail;
1845         }
1846
1847         status = ocfs2_block_group_set_bits(handle,
1848                                             alloc_inode,
1849                                             bg,
1850                                             group_bh,
1851                                             res->sr_bit_offset,
1852                                             res->sr_bits);
1853         if (status < 0) {
1854                 ocfs2_rollback_alloc_dinode_counts(alloc_inode,
1855                                         ac->ac_bh, res->sr_bits, chain);
1856                 mlog_errno(status);
1857                 goto bail;
1858         }
1859
1860         trace_ocfs2_search_chain_end(
1861                         (unsigned long long)le64_to_cpu(fe->i_blkno),
1862                         res->sr_bits);
1863
1864 out_loc_only:
1865         *bits_left = le16_to_cpu(bg->bg_free_bits_count);
1866 bail:
1867         brelse(group_bh);
1868         brelse(prev_group_bh);
1869
1870         if (status)
1871                 mlog_errno(status);
1872         return status;
1873 }
1874
1875 /* will give out up to bits_wanted contiguous bits. */
1876 static int ocfs2_claim_suballoc_bits(struct ocfs2_alloc_context *ac,
1877                                      handle_t *handle,
1878                                      u32 bits_wanted,
1879                                      u32 min_bits,
1880                                      struct ocfs2_suballoc_result *res)
1881 {
1882         int status;
1883         u16 victim, i;
1884         u16 bits_left = 0;
1885         u64 hint = ac->ac_last_group;
1886         struct ocfs2_chain_list *cl;
1887         struct ocfs2_dinode *fe;
1888
1889         BUG_ON(ac->ac_bits_given >= ac->ac_bits_wanted);
1890         BUG_ON(bits_wanted > (ac->ac_bits_wanted - ac->ac_bits_given));
1891         BUG_ON(!ac->ac_bh);
1892
1893         fe = (struct ocfs2_dinode *) ac->ac_bh->b_data;
1894
1895         /* The bh was validated by the inode read during
1896          * ocfs2_reserve_suballoc_bits().  Any corruption is a code bug. */
1897         BUG_ON(!OCFS2_IS_VALID_DINODE(fe));
1898
1899         if (le32_to_cpu(fe->id1.bitmap1.i_used) >=
1900             le32_to_cpu(fe->id1.bitmap1.i_total)) {
1901                 status = ocfs2_error(ac->ac_inode->i_sb,
1902                                      "Chain allocator dinode %llu has %u used bits but only %u total\n",
1903                                      (unsigned long long)le64_to_cpu(fe->i_blkno),
1904                                      le32_to_cpu(fe->id1.bitmap1.i_used),
1905                                      le32_to_cpu(fe->id1.bitmap1.i_total));
1906                 goto bail;
1907         }
1908
1909         res->sr_bg_blkno = hint;
1910         if (res->sr_bg_blkno) {
1911                 /* Attempt to short-circuit the usual search mechanism
1912                  * by jumping straight to the most recently used
1913                  * allocation group. This helps us maintain some
1914                  * contiguousness across allocations. */
1915                 status = ocfs2_search_one_group(ac, handle, bits_wanted,
1916                                                 min_bits, res, &bits_left);
1917                 if (!status)
1918                         goto set_hint;
1919                 if (status < 0 && status != -ENOSPC) {
1920                         mlog_errno(status);
1921                         goto bail;
1922                 }
1923         }
1924
1925         cl = (struct ocfs2_chain_list *) &fe->id2.i_chain;
1926
1927         victim = ocfs2_find_victim_chain(cl);
1928         ac->ac_chain = victim;
1929
1930         status = ocfs2_search_chain(ac, handle, bits_wanted, min_bits,
1931                                     res, &bits_left);
1932         if (!status) {
1933                 if (ocfs2_is_cluster_bitmap(ac->ac_inode))
1934                         hint = res->sr_bg_blkno;
1935                 else
1936                         hint = ocfs2_group_from_res(res);
1937                 goto set_hint;
1938         }
1939         if (status < 0 && status != -ENOSPC) {
1940                 mlog_errno(status);
1941                 goto bail;
1942         }
1943
1944         trace_ocfs2_claim_suballoc_bits(victim);
1945
1946         /* If we didn't pick a good victim, then just default to
1947          * searching each chain in order. Don't allow chain relinking
1948          * because we only calculate enough journal credits for one
1949          * relink per alloc. */
1950         ac->ac_disable_chain_relink = 1;
1951         for (i = 0; i < le16_to_cpu(cl->cl_next_free_rec); i ++) {
1952                 if (i == victim)
1953                         continue;
1954                 if (!cl->cl_recs[i].c_free)
1955                         continue;
1956
1957                 ac->ac_chain = i;
1958                 status = ocfs2_search_chain(ac, handle, bits_wanted, min_bits,
1959                                             res, &bits_left);
1960                 if (!status) {
1961                         hint = ocfs2_group_from_res(res);
1962                         break;
1963                 }
1964                 if (status < 0 && status != -ENOSPC) {
1965                         mlog_errno(status);
1966                         goto bail;
1967                 }
1968         }
1969
1970 set_hint:
1971         if (status != -ENOSPC) {
1972                 /* If the next search of this group is not likely to
1973                  * yield a suitable extent, then we reset the last
1974                  * group hint so as to not waste a disk read */
1975                 if (bits_left < min_bits)
1976                         ac->ac_last_group = 0;
1977                 else
1978                         ac->ac_last_group = hint;
1979         }
1980
1981 bail:
1982         if (status)
1983                 mlog_errno(status);
1984         return status;
1985 }
1986
1987 int ocfs2_claim_metadata(handle_t *handle,
1988                          struct ocfs2_alloc_context *ac,
1989                          u32 bits_wanted,
1990                          u64 *suballoc_loc,
1991                          u16 *suballoc_bit_start,
1992                          unsigned int *num_bits,
1993                          u64 *blkno_start)
1994 {
1995         int status;
1996         struct ocfs2_suballoc_result res = { .sr_blkno = 0, };
1997
1998         BUG_ON(!ac);
1999         BUG_ON(ac->ac_bits_wanted < (ac->ac_bits_given + bits_wanted));
2000         BUG_ON(ac->ac_which != OCFS2_AC_USE_META);
2001
2002         status = ocfs2_claim_suballoc_bits(ac,
2003                                            handle,
2004                                            bits_wanted,
2005                                            1,
2006                                            &res);
2007         if (status < 0) {
2008                 mlog_errno(status);
2009                 goto bail;
2010         }
2011         atomic_inc(&OCFS2_SB(ac->ac_inode->i_sb)->alloc_stats.bg_allocs);
2012
2013         *suballoc_loc = res.sr_bg_blkno;
2014         *suballoc_bit_start = res.sr_bit_offset;
2015         *blkno_start = res.sr_blkno;
2016         ac->ac_bits_given += res.sr_bits;
2017         *num_bits = res.sr_bits;
2018         status = 0;
2019 bail:
2020         if (status)
2021                 mlog_errno(status);
2022         return status;
2023 }
2024
2025 static void ocfs2_init_inode_ac_group(struct inode *dir,
2026                                       struct buffer_head *parent_di_bh,
2027                                       struct ocfs2_alloc_context *ac)
2028 {
2029         struct ocfs2_dinode *di = (struct ocfs2_dinode *)parent_di_bh->b_data;
2030         /*
2031          * Try to allocate inodes from some specific group.
2032          *
2033          * If the parent dir has recorded the last group used in allocation,
2034          * cool, use it. Otherwise if we try to allocate new inode from the
2035          * same slot the parent dir belongs to, use the same chunk.
2036          *
2037          * We are very careful here to avoid the mistake of setting
2038          * ac_last_group to a group descriptor from a different (unlocked) slot.
2039          */
2040         if (OCFS2_I(dir)->ip_last_used_group &&
2041             OCFS2_I(dir)->ip_last_used_slot == ac->ac_alloc_slot)
2042                 ac->ac_last_group = OCFS2_I(dir)->ip_last_used_group;
2043         else if (le16_to_cpu(di->i_suballoc_slot) == ac->ac_alloc_slot) {
2044                 if (di->i_suballoc_loc)
2045                         ac->ac_last_group = le64_to_cpu(di->i_suballoc_loc);
2046                 else
2047                         ac->ac_last_group = ocfs2_which_suballoc_group(
2048                                         le64_to_cpu(di->i_blkno),
2049                                         le16_to_cpu(di->i_suballoc_bit));
2050         }
2051 }
2052
2053 static inline void ocfs2_save_inode_ac_group(struct inode *dir,
2054                                              struct ocfs2_alloc_context *ac)
2055 {
2056         OCFS2_I(dir)->ip_last_used_group = ac->ac_last_group;
2057         OCFS2_I(dir)->ip_last_used_slot = ac->ac_alloc_slot;
2058 }
2059
2060 int ocfs2_find_new_inode_loc(struct inode *dir,
2061                              struct buffer_head *parent_fe_bh,
2062                              struct ocfs2_alloc_context *ac,
2063                              u64 *fe_blkno)
2064 {
2065         int ret;
2066         handle_t *handle = NULL;
2067         struct ocfs2_suballoc_result *res;
2068
2069         BUG_ON(!ac);
2070         BUG_ON(ac->ac_bits_given != 0);
2071         BUG_ON(ac->ac_bits_wanted != 1);
2072         BUG_ON(ac->ac_which != OCFS2_AC_USE_INODE);
2073
2074         res = kzalloc(sizeof(*res), GFP_NOFS);
2075         if (res == NULL) {
2076                 ret = -ENOMEM;
2077                 mlog_errno(ret);
2078                 goto out;
2079         }
2080
2081         ocfs2_init_inode_ac_group(dir, parent_fe_bh, ac);
2082
2083         /*
2084          * The handle started here is for chain relink. Alternatively,
2085          * we could just disable relink for these calls.
2086          */
2087         handle = ocfs2_start_trans(OCFS2_SB(dir->i_sb), OCFS2_SUBALLOC_ALLOC);
2088         if (IS_ERR(handle)) {
2089                 ret = PTR_ERR(handle);
2090                 handle = NULL;
2091                 mlog_errno(ret);
2092                 goto out;
2093         }
2094
2095         /*
2096          * This will instruct ocfs2_claim_suballoc_bits and
2097          * ocfs2_search_one_group to search but save actual allocation
2098          * for later.
2099          */
2100         ac->ac_find_loc_only = 1;
2101
2102         ret = ocfs2_claim_suballoc_bits(ac, handle, 1, 1, res);
2103         if (ret < 0) {
2104                 mlog_errno(ret);
2105                 goto out;
2106         }
2107
2108         ac->ac_find_loc_priv = res;
2109         *fe_blkno = res->sr_blkno;
2110         ocfs2_update_inode_fsync_trans(handle, dir, 0);
2111 out:
2112         if (handle)
2113                 ocfs2_commit_trans(OCFS2_SB(dir->i_sb), handle);
2114
2115         if (ret)
2116                 kfree(res);
2117
2118         return ret;
2119 }
2120
2121 int ocfs2_claim_new_inode_at_loc(handle_t *handle,
2122                                  struct inode *dir,
2123                                  struct ocfs2_alloc_context *ac,
2124                                  u64 *suballoc_loc,
2125                                  u16 *suballoc_bit,
2126                                  u64 di_blkno)
2127 {
2128         int ret;
2129         u16 chain;
2130         struct ocfs2_suballoc_result *res = ac->ac_find_loc_priv;
2131         struct buffer_head *bg_bh = NULL;
2132         struct ocfs2_group_desc *bg;
2133         struct ocfs2_dinode *di = (struct ocfs2_dinode *) ac->ac_bh->b_data;
2134
2135         /*
2136          * Since di_blkno is being passed back in, we check for any
2137          * inconsistencies which may have happened between
2138          * calls. These are code bugs as di_blkno is not expected to
2139          * change once returned from ocfs2_find_new_inode_loc()
2140          */
2141         BUG_ON(res->sr_blkno != di_blkno);
2142
2143         ret = ocfs2_read_group_descriptor(ac->ac_inode, di,
2144                                           res->sr_bg_stable_blkno, &bg_bh);
2145         if (ret) {
2146                 mlog_errno(ret);
2147                 goto out;
2148         }
2149
2150         bg = (struct ocfs2_group_desc *) bg_bh->b_data;
2151         chain = le16_to_cpu(bg->bg_chain);
2152
2153         ret = ocfs2_alloc_dinode_update_counts(ac->ac_inode, handle,
2154                                                ac->ac_bh, res->sr_bits,
2155                                                chain);
2156         if (ret) {
2157                 mlog_errno(ret);
2158                 goto out;
2159         }
2160
2161         ret = ocfs2_block_group_set_bits(handle,
2162                                          ac->ac_inode,
2163                                          bg,
2164                                          bg_bh,
2165                                          res->sr_bit_offset,
2166                                          res->sr_bits);
2167         if (ret < 0) {
2168                 ocfs2_rollback_alloc_dinode_counts(ac->ac_inode,
2169                                                ac->ac_bh, res->sr_bits, chain);
2170                 mlog_errno(ret);
2171                 goto out;
2172         }
2173
2174         trace_ocfs2_claim_new_inode_at_loc((unsigned long long)di_blkno,
2175                                            res->sr_bits);
2176
2177         atomic_inc(&OCFS2_SB(ac->ac_inode->i_sb)->alloc_stats.bg_allocs);
2178
2179         BUG_ON(res->sr_bits != 1);
2180
2181         *suballoc_loc = res->sr_bg_blkno;
2182         *suballoc_bit = res->sr_bit_offset;
2183         ac->ac_bits_given++;
2184         ocfs2_save_inode_ac_group(dir, ac);
2185
2186 out:
2187         brelse(bg_bh);
2188
2189         return ret;
2190 }
2191
2192 int ocfs2_claim_new_inode(handle_t *handle,
2193                           struct inode *dir,
2194                           struct buffer_head *parent_fe_bh,
2195                           struct ocfs2_alloc_context *ac,
2196                           u64 *suballoc_loc,
2197                           u16 *suballoc_bit,
2198                           u64 *fe_blkno)
2199 {
2200         int status;
2201         struct ocfs2_suballoc_result res;
2202
2203         BUG_ON(!ac);
2204         BUG_ON(ac->ac_bits_given != 0);
2205         BUG_ON(ac->ac_bits_wanted != 1);
2206         BUG_ON(ac->ac_which != OCFS2_AC_USE_INODE);
2207
2208         ocfs2_init_inode_ac_group(dir, parent_fe_bh, ac);
2209
2210         status = ocfs2_claim_suballoc_bits(ac,
2211                                            handle,
2212                                            1,
2213                                            1,
2214                                            &res);
2215         if (status < 0) {
2216                 mlog_errno(status);
2217                 goto bail;
2218         }
2219         atomic_inc(&OCFS2_SB(ac->ac_inode->i_sb)->alloc_stats.bg_allocs);
2220
2221         BUG_ON(res.sr_bits != 1);
2222
2223         *suballoc_loc = res.sr_bg_blkno;
2224         *suballoc_bit = res.sr_bit_offset;
2225         *fe_blkno = res.sr_blkno;
2226         ac->ac_bits_given++;
2227         ocfs2_save_inode_ac_group(dir, ac);
2228         status = 0;
2229 bail:
2230         if (status)
2231                 mlog_errno(status);
2232         return status;
2233 }
2234
2235 /* translate a group desc. blkno and it's bitmap offset into
2236  * disk cluster offset. */
2237 static inline u32 ocfs2_desc_bitmap_to_cluster_off(struct inode *inode,
2238                                                    u64 bg_blkno,
2239                                                    u16 bg_bit_off)
2240 {
2241         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
2242         u32 cluster = 0;
2243
2244         BUG_ON(!ocfs2_is_cluster_bitmap(inode));
2245
2246         if (bg_blkno != osb->first_cluster_group_blkno)
2247                 cluster = ocfs2_blocks_to_clusters(inode->i_sb, bg_blkno);
2248         cluster += (u32) bg_bit_off;
2249         return cluster;
2250 }
2251
2252 /* given a cluster offset, calculate which block group it belongs to
2253  * and return that block offset. */
2254 u64 ocfs2_which_cluster_group(struct inode *inode, u32 cluster)
2255 {
2256         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
2257         u32 group_no;
2258
2259         BUG_ON(!ocfs2_is_cluster_bitmap(inode));
2260
2261         group_no = cluster / osb->bitmap_cpg;
2262         if (!group_no)
2263                 return osb->first_cluster_group_blkno;
2264         return ocfs2_clusters_to_blocks(inode->i_sb,
2265                                         group_no * osb->bitmap_cpg);
2266 }
2267
2268 /* given the block number of a cluster start, calculate which cluster
2269  * group and descriptor bitmap offset that corresponds to. */
2270 static inline void ocfs2_block_to_cluster_group(struct inode *inode,
2271                                                 u64 data_blkno,
2272                                                 u64 *bg_blkno,
2273                                                 u16 *bg_bit_off)
2274 {
2275         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
2276         u32 data_cluster = ocfs2_blocks_to_clusters(osb->sb, data_blkno);
2277
2278         BUG_ON(!ocfs2_is_cluster_bitmap(inode));
2279
2280         *bg_blkno = ocfs2_which_cluster_group(inode,
2281                                               data_cluster);
2282
2283         if (*bg_blkno == osb->first_cluster_group_blkno)
2284                 *bg_bit_off = (u16) data_cluster;
2285         else
2286                 *bg_bit_off = (u16) ocfs2_blocks_to_clusters(osb->sb,
2287                                                              data_blkno - *bg_blkno);
2288 }
2289
2290 /*
2291  * min_bits - minimum contiguous chunk from this total allocation we
2292  * can handle. set to what we asked for originally for a full
2293  * contig. allocation, set to '1' to indicate we can deal with extents
2294  * of any size.
2295  */
2296 int __ocfs2_claim_clusters(handle_t *handle,
2297                            struct ocfs2_alloc_context *ac,
2298                            u32 min_clusters,
2299                            u32 max_clusters,
2300                            u32 *cluster_start,
2301                            u32 *num_clusters)
2302 {
2303         int status;
2304         unsigned int bits_wanted = max_clusters;
2305         struct ocfs2_suballoc_result res = { .sr_blkno = 0, };
2306         struct ocfs2_super *osb = OCFS2_SB(ac->ac_inode->i_sb);
2307
2308         BUG_ON(ac->ac_bits_given >= ac->ac_bits_wanted);
2309
2310         BUG_ON(ac->ac_which != OCFS2_AC_USE_LOCAL
2311                && ac->ac_which != OCFS2_AC_USE_MAIN);
2312
2313         if (ac->ac_which == OCFS2_AC_USE_LOCAL) {
2314                 WARN_ON(min_clusters > 1);
2315
2316                 status = ocfs2_claim_local_alloc_bits(osb,
2317                                                       handle,
2318                                                       ac,
2319                                                       bits_wanted,
2320                                                       cluster_start,
2321                                                       num_clusters);
2322                 if (!status)
2323                         atomic_inc(&osb->alloc_stats.local_data);
2324         } else {
2325                 if (min_clusters > (osb->bitmap_cpg - 1)) {
2326                         /* The only paths asking for contiguousness
2327                          * should know about this already. */
2328                         mlog(ML_ERROR, "minimum allocation requested %u exceeds "
2329                              "group bitmap size %u!\n", min_clusters,
2330                              osb->bitmap_cpg);
2331                         status = -ENOSPC;
2332                         goto bail;
2333                 }
2334                 /* clamp the current request down to a realistic size. */
2335                 if (bits_wanted > (osb->bitmap_cpg - 1))
2336                         bits_wanted = osb->bitmap_cpg - 1;
2337
2338                 status = ocfs2_claim_suballoc_bits(ac,
2339                                                    handle,
2340                                                    bits_wanted,
2341                                                    min_clusters,
2342                                                    &res);
2343                 if (!status) {
2344                         BUG_ON(res.sr_blkno); /* cluster alloc can't set */
2345                         *cluster_start =
2346                                 ocfs2_desc_bitmap_to_cluster_off(ac->ac_inode,
2347                                                                  res.sr_bg_blkno,
2348                                                                  res.sr_bit_offset);
2349                         atomic_inc(&osb->alloc_stats.bitmap_data);
2350                         *num_clusters = res.sr_bits;
2351                 }
2352         }
2353         if (status < 0) {
2354                 if (status != -ENOSPC)
2355                         mlog_errno(status);
2356                 goto bail;
2357         }
2358
2359         ac->ac_bits_given += *num_clusters;
2360
2361 bail:
2362         if (status)
2363                 mlog_errno(status);
2364         return status;
2365 }
2366
2367 int ocfs2_claim_clusters(handle_t *handle,
2368                          struct ocfs2_alloc_context *ac,
2369                          u32 min_clusters,
2370                          u32 *cluster_start,
2371                          u32 *num_clusters)
2372 {
2373         unsigned int bits_wanted = ac->ac_bits_wanted - ac->ac_bits_given;
2374
2375         return __ocfs2_claim_clusters(handle, ac, min_clusters,
2376                                       bits_wanted, cluster_start, num_clusters);
2377 }
2378
2379 static int ocfs2_block_group_clear_bits(handle_t *handle,
2380                                         struct inode *alloc_inode,
2381                                         struct ocfs2_group_desc *bg,
2382                                         struct buffer_head *group_bh,
2383                                         unsigned int bit_off,
2384                                         unsigned int num_bits,
2385                                         void (*undo_fn)(unsigned int bit,
2386                                                         unsigned long *bmap))
2387 {
2388         int status;
2389         unsigned int tmp;
2390         struct ocfs2_group_desc *undo_bg = NULL;
2391         struct journal_head *jh;
2392
2393         /* The caller got this descriptor from
2394          * ocfs2_read_group_descriptor().  Any corruption is a code bug. */
2395         BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
2396
2397         trace_ocfs2_block_group_clear_bits(bit_off, num_bits);
2398
2399         BUG_ON(undo_fn && !ocfs2_is_cluster_bitmap(alloc_inode));
2400         status = ocfs2_journal_access_gd(handle, INODE_CACHE(alloc_inode),
2401                                          group_bh,
2402                                          undo_fn ?
2403                                          OCFS2_JOURNAL_ACCESS_UNDO :
2404                                          OCFS2_JOURNAL_ACCESS_WRITE);
2405         if (status < 0) {
2406                 mlog_errno(status);
2407                 goto bail;
2408         }
2409
2410         jh = bh2jh(group_bh);
2411         if (undo_fn) {
2412                 spin_lock(&jh->b_state_lock);
2413                 undo_bg = (struct ocfs2_group_desc *) jh->b_committed_data;
2414                 BUG_ON(!undo_bg);
2415         }
2416
2417         tmp = num_bits;
2418         while(tmp--) {
2419                 ocfs2_clear_bit((bit_off + tmp),
2420                                 (unsigned long *) bg->bg_bitmap);
2421                 if (undo_fn)
2422                         undo_fn(bit_off + tmp,
2423                                 (unsigned long *) undo_bg->bg_bitmap);
2424         }
2425         le16_add_cpu(&bg->bg_free_bits_count, num_bits);
2426         if (le16_to_cpu(bg->bg_free_bits_count) > le16_to_cpu(bg->bg_bits)) {
2427                 if (undo_fn)
2428                         spin_unlock(&jh->b_state_lock);
2429                 return ocfs2_error(alloc_inode->i_sb, "Group descriptor # %llu has bit count %u but claims %u are freed. num_bits %d\n",
2430                                    (unsigned long long)le64_to_cpu(bg->bg_blkno),
2431                                    le16_to_cpu(bg->bg_bits),
2432                                    le16_to_cpu(bg->bg_free_bits_count),
2433                                    num_bits);
2434         }
2435
2436         if (undo_fn)
2437                 spin_unlock(&jh->b_state_lock);
2438
2439         ocfs2_journal_dirty(handle, group_bh);
2440 bail:
2441         return status;
2442 }
2443
2444 /*
2445  * expects the suballoc inode to already be locked.
2446  */
2447 static int _ocfs2_free_suballoc_bits(handle_t *handle,
2448                                      struct inode *alloc_inode,
2449                                      struct buffer_head *alloc_bh,
2450                                      unsigned int start_bit,
2451                                      u64 bg_blkno,
2452                                      unsigned int count,
2453                                      void (*undo_fn)(unsigned int bit,
2454                                                      unsigned long *bitmap))
2455 {
2456         int status = 0;
2457         u32 tmp_used;
2458         struct ocfs2_dinode *fe = (struct ocfs2_dinode *) alloc_bh->b_data;
2459         struct ocfs2_chain_list *cl = &fe->id2.i_chain;
2460         struct buffer_head *group_bh = NULL;
2461         struct ocfs2_group_desc *group;
2462
2463         /* The alloc_bh comes from ocfs2_free_dinode() or
2464          * ocfs2_free_clusters().  The callers have all locked the
2465          * allocator and gotten alloc_bh from the lock call.  This
2466          * validates the dinode buffer.  Any corruption that has happened
2467          * is a code bug. */
2468         BUG_ON(!OCFS2_IS_VALID_DINODE(fe));
2469         BUG_ON((count + start_bit) > ocfs2_bits_per_group(cl));
2470
2471         trace_ocfs2_free_suballoc_bits(
2472                 (unsigned long long)OCFS2_I(alloc_inode)->ip_blkno,
2473                 (unsigned long long)bg_blkno,
2474                 start_bit, count);
2475
2476         status = ocfs2_read_group_descriptor(alloc_inode, fe, bg_blkno,
2477                                              &group_bh);
2478         if (status < 0) {
2479                 mlog_errno(status);
2480                 goto bail;
2481         }
2482         group = (struct ocfs2_group_desc *) group_bh->b_data;
2483
2484         BUG_ON((count + start_bit) > le16_to_cpu(group->bg_bits));
2485
2486         status = ocfs2_block_group_clear_bits(handle, alloc_inode,
2487                                               group, group_bh,
2488                                               start_bit, count, undo_fn);
2489         if (status < 0) {
2490                 mlog_errno(status);
2491                 goto bail;
2492         }
2493
2494         status = ocfs2_journal_access_di(handle, INODE_CACHE(alloc_inode),
2495                                          alloc_bh, OCFS2_JOURNAL_ACCESS_WRITE);
2496         if (status < 0) {
2497                 mlog_errno(status);
2498                 ocfs2_block_group_set_bits(handle, alloc_inode, group, group_bh,
2499                                 start_bit, count);
2500                 goto bail;
2501         }
2502
2503         le32_add_cpu(&cl->cl_recs[le16_to_cpu(group->bg_chain)].c_free,
2504                      count);
2505         tmp_used = le32_to_cpu(fe->id1.bitmap1.i_used);
2506         fe->id1.bitmap1.i_used = cpu_to_le32(tmp_used - count);
2507         ocfs2_journal_dirty(handle, alloc_bh);
2508
2509 bail:
2510         brelse(group_bh);
2511         return status;
2512 }
2513
2514 int ocfs2_free_suballoc_bits(handle_t *handle,
2515                              struct inode *alloc_inode,
2516                              struct buffer_head *alloc_bh,
2517                              unsigned int start_bit,
2518                              u64 bg_blkno,
2519                              unsigned int count)
2520 {
2521         return _ocfs2_free_suballoc_bits(handle, alloc_inode, alloc_bh,
2522                                          start_bit, bg_blkno, count, NULL);
2523 }
2524
2525 int ocfs2_free_dinode(handle_t *handle,
2526                       struct inode *inode_alloc_inode,
2527                       struct buffer_head *inode_alloc_bh,
2528                       struct ocfs2_dinode *di)
2529 {
2530         u64 blk = le64_to_cpu(di->i_blkno);
2531         u16 bit = le16_to_cpu(di->i_suballoc_bit);
2532         u64 bg_blkno = ocfs2_which_suballoc_group(blk, bit);
2533
2534         if (di->i_suballoc_loc)
2535                 bg_blkno = le64_to_cpu(di->i_suballoc_loc);
2536         return ocfs2_free_suballoc_bits(handle, inode_alloc_inode,
2537                                         inode_alloc_bh, bit, bg_blkno, 1);
2538 }
2539
2540 static int _ocfs2_free_clusters(handle_t *handle,
2541                                 struct inode *bitmap_inode,
2542                                 struct buffer_head *bitmap_bh,
2543                                 u64 start_blk,
2544                                 unsigned int num_clusters,
2545                                 void (*undo_fn)(unsigned int bit,
2546                                                 unsigned long *bitmap))
2547 {
2548         int status;
2549         u16 bg_start_bit;
2550         u64 bg_blkno;
2551
2552         /* You can't ever have a contiguous set of clusters
2553          * bigger than a block group bitmap so we never have to worry
2554          * about looping on them.
2555          * This is expensive. We can safely remove once this stuff has
2556          * gotten tested really well. */
2557         BUG_ON(start_blk != ocfs2_clusters_to_blocks(bitmap_inode->i_sb,
2558                                 ocfs2_blocks_to_clusters(bitmap_inode->i_sb,
2559                                                          start_blk)));
2560
2561
2562         ocfs2_block_to_cluster_group(bitmap_inode, start_blk, &bg_blkno,
2563                                      &bg_start_bit);
2564
2565         trace_ocfs2_free_clusters((unsigned long long)bg_blkno,
2566                         (unsigned long long)start_blk,
2567                         bg_start_bit, num_clusters);
2568
2569         status = _ocfs2_free_suballoc_bits(handle, bitmap_inode, bitmap_bh,
2570                                            bg_start_bit, bg_blkno,
2571                                            num_clusters, undo_fn);
2572         if (status < 0) {
2573                 mlog_errno(status);
2574                 goto out;
2575         }
2576
2577         ocfs2_local_alloc_seen_free_bits(OCFS2_SB(bitmap_inode->i_sb),
2578                                          num_clusters);
2579
2580 out:
2581         return status;
2582 }
2583
2584 int ocfs2_free_clusters(handle_t *handle,
2585                         struct inode *bitmap_inode,
2586                         struct buffer_head *bitmap_bh,
2587                         u64 start_blk,
2588                         unsigned int num_clusters)
2589 {
2590         return _ocfs2_free_clusters(handle, bitmap_inode, bitmap_bh,
2591                                     start_blk, num_clusters,
2592                                     _ocfs2_set_bit);
2593 }
2594
2595 /*
2596  * Give never-used clusters back to the global bitmap.  We don't need
2597  * to protect these bits in the undo buffer.
2598  */
2599 int ocfs2_release_clusters(handle_t *handle,
2600                            struct inode *bitmap_inode,
2601                            struct buffer_head *bitmap_bh,
2602                            u64 start_blk,
2603                            unsigned int num_clusters)
2604 {
2605         return _ocfs2_free_clusters(handle, bitmap_inode, bitmap_bh,
2606                                     start_blk, num_clusters,
2607                                     _ocfs2_clear_bit);
2608 }
2609
2610 /*
2611  * For a given allocation, determine which allocators will need to be
2612  * accessed, and lock them, reserving the appropriate number of bits.
2613  *
2614  * Sparse file systems call this from ocfs2_write_begin_nolock()
2615  * and ocfs2_allocate_unwritten_extents().
2616  *
2617  * File systems which don't support holes call this from
2618  * ocfs2_extend_allocation().
2619  */
2620 int ocfs2_lock_allocators(struct inode *inode,
2621                           struct ocfs2_extent_tree *et,
2622                           u32 clusters_to_add, u32 extents_to_split,
2623                           struct ocfs2_alloc_context **data_ac,
2624                           struct ocfs2_alloc_context **meta_ac)
2625 {
2626         int ret = 0, num_free_extents;
2627         unsigned int max_recs_needed = clusters_to_add + 2 * extents_to_split;
2628         struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
2629
2630         *meta_ac = NULL;
2631         if (data_ac)
2632                 *data_ac = NULL;
2633
2634         BUG_ON(clusters_to_add != 0 && data_ac == NULL);
2635
2636         num_free_extents = ocfs2_num_free_extents(et);
2637         if (num_free_extents < 0) {
2638                 ret = num_free_extents;
2639                 mlog_errno(ret);
2640                 goto out;
2641         }
2642
2643         /*
2644          * Sparse allocation file systems need to be more conservative
2645          * with reserving room for expansion - the actual allocation
2646          * happens while we've got a journal handle open so re-taking
2647          * a cluster lock (because we ran out of room for another
2648          * extent) will violate ordering rules.
2649          *
2650          * Most of the time we'll only be seeing this 1 cluster at a time
2651          * anyway.
2652          *
2653          * Always lock for any unwritten extents - we might want to
2654          * add blocks during a split.
2655          */
2656         if (!num_free_extents ||
2657             (ocfs2_sparse_alloc(osb) && num_free_extents < max_recs_needed)) {
2658                 ret = ocfs2_reserve_new_metadata(osb, et->et_root_el, meta_ac);
2659                 if (ret < 0) {
2660                         if (ret != -ENOSPC)
2661                                 mlog_errno(ret);
2662                         goto out;
2663                 }
2664         }
2665
2666         if (clusters_to_add == 0)
2667                 goto out;
2668
2669         ret = ocfs2_reserve_clusters(osb, clusters_to_add, data_ac);
2670         if (ret < 0) {
2671                 if (ret != -ENOSPC)
2672                         mlog_errno(ret);
2673                 goto out;
2674         }
2675
2676 out:
2677         if (ret) {
2678                 if (*meta_ac) {
2679                         ocfs2_free_alloc_context(*meta_ac);
2680                         *meta_ac = NULL;
2681                 }
2682
2683                 /*
2684                  * We cannot have an error and a non null *data_ac.
2685                  */
2686         }
2687
2688         return ret;
2689 }
2690
2691 /*
2692  * Read the inode specified by blkno to get suballoc_slot and
2693  * suballoc_bit.
2694  */
2695 static int ocfs2_get_suballoc_slot_bit(struct ocfs2_super *osb, u64 blkno,
2696                                        u16 *suballoc_slot, u64 *group_blkno,
2697                                        u16 *suballoc_bit)
2698 {
2699         int status;
2700         struct buffer_head *inode_bh = NULL;
2701         struct ocfs2_dinode *inode_fe;
2702
2703         trace_ocfs2_get_suballoc_slot_bit((unsigned long long)blkno);
2704
2705         /* dirty read disk */
2706         status = ocfs2_read_blocks_sync(osb, blkno, 1, &inode_bh);
2707         if (status < 0) {
2708                 mlog(ML_ERROR, "read block %llu failed %d\n",
2709                      (unsigned long long)blkno, status);
2710                 goto bail;
2711         }
2712
2713         inode_fe = (struct ocfs2_dinode *) inode_bh->b_data;
2714         if (!OCFS2_IS_VALID_DINODE(inode_fe)) {
2715                 mlog(ML_ERROR, "invalid inode %llu requested\n",
2716                      (unsigned long long)blkno);
2717                 status = -EINVAL;
2718                 goto bail;
2719         }
2720
2721         if (le16_to_cpu(inode_fe->i_suballoc_slot) != (u16)OCFS2_INVALID_SLOT &&
2722             (u32)le16_to_cpu(inode_fe->i_suballoc_slot) > osb->max_slots - 1) {
2723                 mlog(ML_ERROR, "inode %llu has invalid suballoc slot %u\n",
2724                      (unsigned long long)blkno,
2725                      (u32)le16_to_cpu(inode_fe->i_suballoc_slot));
2726                 status = -EINVAL;
2727                 goto bail;
2728         }
2729
2730         if (suballoc_slot)
2731                 *suballoc_slot = le16_to_cpu(inode_fe->i_suballoc_slot);
2732         if (suballoc_bit)
2733                 *suballoc_bit = le16_to_cpu(inode_fe->i_suballoc_bit);
2734         if (group_blkno)
2735                 *group_blkno = le64_to_cpu(inode_fe->i_suballoc_loc);
2736
2737 bail:
2738         brelse(inode_bh);
2739
2740         if (status)
2741                 mlog_errno(status);
2742         return status;
2743 }
2744
2745 /*
2746  * test whether bit is SET in allocator bitmap or not.  on success, 0
2747  * is returned and *res is 1 for SET; 0 otherwise.  when fails, errno
2748  * is returned and *res is meaningless.  Call this after you have
2749  * cluster locked against suballoc, or you may get a result based on
2750  * non-up2date contents
2751  */
2752 static int ocfs2_test_suballoc_bit(struct ocfs2_super *osb,
2753                                    struct inode *suballoc,
2754                                    struct buffer_head *alloc_bh,
2755                                    u64 group_blkno, u64 blkno,
2756                                    u16 bit, int *res)
2757 {
2758         struct ocfs2_dinode *alloc_di;
2759         struct ocfs2_group_desc *group;
2760         struct buffer_head *group_bh = NULL;
2761         u64 bg_blkno;
2762         int status;
2763
2764         trace_ocfs2_test_suballoc_bit((unsigned long long)blkno,
2765                                       (unsigned int)bit);
2766
2767         alloc_di = (struct ocfs2_dinode *)alloc_bh->b_data;
2768         if ((bit + 1) > ocfs2_bits_per_group(&alloc_di->id2.i_chain)) {
2769                 mlog(ML_ERROR, "suballoc bit %u out of range of %u\n",
2770                      (unsigned int)bit,
2771                      ocfs2_bits_per_group(&alloc_di->id2.i_chain));
2772                 status = -EINVAL;
2773                 goto bail;
2774         }
2775
2776         bg_blkno = group_blkno ? group_blkno :
2777                    ocfs2_which_suballoc_group(blkno, bit);
2778         status = ocfs2_read_group_descriptor(suballoc, alloc_di, bg_blkno,
2779                                              &group_bh);
2780         if (status < 0) {
2781                 mlog(ML_ERROR, "read group %llu failed %d\n",
2782                      (unsigned long long)bg_blkno, status);
2783                 goto bail;
2784         }
2785
2786         group = (struct ocfs2_group_desc *) group_bh->b_data;
2787         *res = ocfs2_test_bit(bit, (unsigned long *)group->bg_bitmap);
2788
2789 bail:
2790         brelse(group_bh);
2791
2792         if (status)
2793                 mlog_errno(status);
2794         return status;
2795 }
2796
2797 /*
2798  * Test if the bit representing this inode (blkno) is set in the
2799  * suballocator.
2800  *
2801  * On success, 0 is returned and *res is 1 for SET; 0 otherwise.
2802  *
2803  * In the event of failure, a negative value is returned and *res is
2804  * meaningless.
2805  *
2806  * Callers must make sure to hold nfs_sync_lock to prevent
2807  * ocfs2_delete_inode() on another node from accessing the same
2808  * suballocator concurrently.
2809  */
2810 int ocfs2_test_inode_bit(struct ocfs2_super *osb, u64 blkno, int *res)
2811 {
2812         int status;
2813         u64 group_blkno = 0;
2814         u16 suballoc_bit = 0, suballoc_slot = 0;
2815         struct inode *inode_alloc_inode;
2816         struct buffer_head *alloc_bh = NULL;
2817
2818         trace_ocfs2_test_inode_bit((unsigned long long)blkno);
2819
2820         status = ocfs2_get_suballoc_slot_bit(osb, blkno, &suballoc_slot,
2821                                              &group_blkno, &suballoc_bit);
2822         if (status < 0) {
2823                 mlog(ML_ERROR, "get alloc slot and bit failed %d\n", status);
2824                 goto bail;
2825         }
2826
2827         if (suballoc_slot == (u16)OCFS2_INVALID_SLOT)
2828                 inode_alloc_inode = ocfs2_get_system_file_inode(osb,
2829                         GLOBAL_INODE_ALLOC_SYSTEM_INODE, suballoc_slot);
2830         else
2831                 inode_alloc_inode = ocfs2_get_system_file_inode(osb,
2832                         INODE_ALLOC_SYSTEM_INODE, suballoc_slot);
2833         if (!inode_alloc_inode) {
2834                 /* the error code could be inaccurate, but we are not able to
2835                  * get the correct one. */
2836                 status = -EINVAL;
2837                 mlog(ML_ERROR, "unable to get alloc inode in slot %u\n",
2838                      (u32)suballoc_slot);
2839                 goto bail;
2840         }
2841
2842         inode_lock(inode_alloc_inode);
2843         status = ocfs2_inode_lock(inode_alloc_inode, &alloc_bh, 0);
2844         if (status < 0) {
2845                 inode_unlock(inode_alloc_inode);
2846                 iput(inode_alloc_inode);
2847                 mlog(ML_ERROR, "lock on alloc inode on slot %u failed %d\n",
2848                      (u32)suballoc_slot, status);
2849                 goto bail;
2850         }
2851
2852         status = ocfs2_test_suballoc_bit(osb, inode_alloc_inode, alloc_bh,
2853                                          group_blkno, blkno, suballoc_bit, res);
2854         if (status < 0)
2855                 mlog(ML_ERROR, "test suballoc bit failed %d\n", status);
2856
2857         ocfs2_inode_unlock(inode_alloc_inode, 0);
2858         inode_unlock(inode_alloc_inode);
2859
2860         iput(inode_alloc_inode);
2861         brelse(alloc_bh);
2862 bail:
2863         if (status)
2864                 mlog_errno(status);
2865         return status;
2866 }