fs/hpfs/anode.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  linux/fs/hpfs/anode.c
   4  *
   5  *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
   6  *
   7  *  handling HPFS anode tree that contains file allocation info
   8  */
   9
  10 #include "hpfs_fn.h"
  11
  12 /* Find a sector in allocation tree */
  13
  14 secno hpfs_bplus_lookup(struct super_block *s, struct inode *inode,
  15                    struct bplus_header *btree, unsigned sec,
  16                    struct buffer_head *bh)
  17 {
  18         anode_secno a = -1;
  19         struct anode *anode;
  20         int i;
  21         int c1, c2 = 0;
  22         go_down:
  23         if (hpfs_sb(s)->sb_chk) if (hpfs_stop_cycles(s, a, &c1, &c2, "hpfs_bplus_lookup")) return -1;
  24         if (bp_internal(btree)) {
  25                 for (i = 0; i < btree->n_used_nodes; i++)
  26                         if (le32_to_cpu(btree->u.internal[i].file_secno) > sec) {
  27                                 a = le32_to_cpu(btree->u.internal[i].down);
  28                                 brelse(bh);
  29                                 if (!(anode = hpfs_map_anode(s, a, &bh))) return -1;
  30                                 btree = &anode->btree;
  31                                 goto go_down;
  32                         }
  33                 hpfs_error(s, "sector %08x not found in internal anode %08x", sec, a);
  34                 brelse(bh);
  35                 return -1;
  36         }
  37         for (i = 0; i < btree->n_used_nodes; i++)
  38                 if (le32_to_cpu(btree->u.external[i].file_secno) <= sec &&
  39                     le32_to_cpu(btree->u.external[i].file_secno) + le32_to_cpu(btree->u.external[i].length) > sec) {
  40                         a = le32_to_cpu(btree->u.external[i].disk_secno) + sec - le32_to_cpu(btree->u.external[i].file_secno);
  41                         if (hpfs_sb(s)->sb_chk) if (hpfs_chk_sectors(s, a, 1, "data")) {
  42                                 brelse(bh);
  43                                 return -1;
  44                         }
  45                         if (inode) {
  46                                 struct hpfs_inode_info *hpfs_inode = hpfs_i(inode);
  47                                 hpfs_inode->i_file_sec = le32_to_cpu(btree->u.external[i].file_secno);
  48                                 hpfs_inode->i_disk_sec = le32_to_cpu(btree->u.external[i].disk_secno);
  49                                 hpfs_inode->i_n_secs = le32_to_cpu(btree->u.external[i].length);
  50                         }
  51                         brelse(bh);
  52                         return a;
  53                 }
  54         hpfs_error(s, "sector %08x not found in external anode %08x", sec, a);
  55         brelse(bh);
  56         return -1;
  57 }
  58
  59 /* Add a sector to tree */
  60
  61 secno hpfs_add_sector_to_btree(struct super_block *s, secno node, int fnod, unsigned fsecno)
  62 {
  63         struct bplus_header *btree;
  64         struct anode *anode = NULL, *ranode = NULL;
  65         struct fnode *fnode;
  66         anode_secno a, na = -1, ra, up = -1;
  67         secno se;
  68         struct buffer_head *bh, *bh1, *bh2;
  69         int n;
  70         unsigned fs;
  71         int c1, c2 = 0;
  72         if (fnod) {
  73                 if (!(fnode = hpfs_map_fnode(s, node, &bh))) return -1;
  74                 btree = &fnode->btree;
  75         } else {
  76                 if (!(anode = hpfs_map_anode(s, node, &bh))) return -1;
  77                 btree = &anode->btree;
  78         }
  79         a = node;
  80         go_down:
  81         if ((n = btree->n_used_nodes - 1) < -!!fnod) {
  82                 hpfs_error(s, "anode %08x has no entries", a);
  83                 brelse(bh);
  84                 return -1;
  85         }
  86         if (bp_internal(btree)) {
  87                 a = le32_to_cpu(btree->u.internal[n].down);
  88                 btree->u.internal[n].file_secno = cpu_to_le32(-1);
  89                 mark_buffer_dirty(bh);
  90                 brelse(bh);
  91                 if (hpfs_sb(s)->sb_chk)
  92                         if (hpfs_stop_cycles(s, a, &c1, &c2, "hpfs_add_sector_to_btree #1")) return -1;
  93                 if (!(anode = hpfs_map_anode(s, a, &bh))) return -1;
  94                 btree = &anode->btree;
  95                 goto go_down;
  96         }
  97         if (n >= 0) {
  98                 if (le32_to_cpu(btree->u.external[n].file_secno) + le32_to_cpu(btree->u.external[n].length) != fsecno) {
  99                         hpfs_error(s, "allocated size %08x, trying to add sector %08x, %cnode %08x",
 100                                 le32_to_cpu(btree->u.external[n].file_secno) + le32_to_cpu(btree->u.external[n].length), fsecno,
 101                                 fnod?'f':'a', node);
 102                         brelse(bh);
 103                         return -1;
 104                 }
 105                 if (hpfs_alloc_if_possible(s, se = le32_to_cpu(btree->u.external[n].disk_secno) + le32_to_cpu(btree->u.external[n].length))) {
 106                         le32_add_cpu(&btree->u.external[n].length, 1);
 107                         mark_buffer_dirty(bh);
 108                         brelse(bh);
 109                         return se;
 110                 }
 111         } else {
 112                 if (fsecno) {
 113                         hpfs_error(s, "empty file %08x, trying to add sector %08x", node, fsecno);
 114                         brelse(bh);
 115                         return -1;
 116                 }
 117                 se = !fnod ? node : (node + 16384) & ~16383;
 118         }
 119         if (!(se = hpfs_alloc_sector(s, se, 1, fsecno*ALLOC_M>ALLOC_FWD_MAX ? ALLOC_FWD_MAX : fsecno*ALLOC_M<ALLOC_FWD_MIN ? ALLOC_FWD_MIN : fsecno*ALLOC_M))) {
 120                 brelse(bh);
 121                 return -1;
 122         }
 123         fs = n < 0 ? 0 : le32_to_cpu(btree->u.external[n].file_secno) + le32_to_cpu(btree->u.external[n].length);
 124         if (!btree->n_free_nodes) {
 125                 up = a != node ? le32_to_cpu(anode->up) : -1;
 126                 if (!(anode = hpfs_alloc_anode(s, a, &na, &bh1))) {
 127                         brelse(bh);
 128                         hpfs_free_sectors(s, se, 1);
 129                         return -1;
 130                 }
 131                 if (a == node && fnod) {
 132                         anode->up = cpu_to_le32(node);
 133                         anode->btree.flags |= BP_fnode_parent;
 134                         anode->btree.n_used_nodes = btree->n_used_nodes;
 135                         anode->btree.first_free = btree->first_free;
 136                         anode->btree.n_free_nodes = 40 - anode->btree.n_used_nodes;
 137                         memcpy(&anode->u, &btree->u, btree->n_used_nodes * 12);
 138                         btree->flags |= BP_internal;
 139                         btree->n_free_nodes = 11;
 140                         btree->n_used_nodes = 1;
 141                         btree->first_free = cpu_to_le16((char *)&(btree->u.internal[1]) - (char *)btree);
 142                         btree->u.internal[0].file_secno = cpu_to_le32(-1);
 143                         btree->u.internal[0].down = cpu_to_le32(na);
 144                         mark_buffer_dirty(bh);
 145                 } else if (!(ranode = hpfs_alloc_anode(s, /*a*/0, &ra, &bh2))) {
 146                         brelse(bh);
 147                         brelse(bh1);
 148                         hpfs_free_sectors(s, se, 1);
 149                         hpfs_free_sectors(s, na, 1);
 150                         return -1;
 151                 }
 152                 brelse(bh);
 153                 bh = bh1;
 154                 btree = &anode->btree;
 155         }
 156         btree->n_free_nodes--; n = btree->n_used_nodes++;
 157         le16_add_cpu(&btree->first_free, 12);
 158         btree->u.external[n].disk_secno = cpu_to_le32(se);
 159         btree->u.external[n].file_secno = cpu_to_le32(fs);
 160         btree->u.external[n].length = cpu_to_le32(1);
 161         mark_buffer_dirty(bh);
 162         brelse(bh);
 163         if ((a == node && fnod) || na == -1) return se;
 164         c2 = 0;
 165         while (up != (anode_secno)-1) {
 166                 struct anode *new_anode;
 167                 if (hpfs_sb(s)->sb_chk)
 168                         if (hpfs_stop_cycles(s, up, &c1, &c2, "hpfs_add_sector_to_btree #2")) return -1;
 169                 if (up != node || !fnod) {
 170                         if (!(anode = hpfs_map_anode(s, up, &bh))) return -1;
 171                         btree = &anode->btree;
 172                 } else {
 173                         if (!(fnode = hpfs_map_fnode(s, up, &bh))) return -1;
 174                         btree = &fnode->btree;
 175                 }
 176                 if (btree->n_free_nodes) {
 177                         btree->n_free_nodes--; n = btree->n_used_nodes++;
 178                         le16_add_cpu(&btree->first_free, 8);
 179                         btree->u.internal[n].file_secno = cpu_to_le32(-1);
 180                         btree->u.internal[n].down = cpu_to_le32(na);
 181                         btree->u.internal[n-1].file_secno = cpu_to_le32(fs);
 182                         mark_buffer_dirty(bh);
 183                         brelse(bh);
 184                         brelse(bh2);
 185                         hpfs_free_sectors(s, ra, 1);
 186                         if ((anode = hpfs_map_anode(s, na, &bh))) {
 187                                 anode->up = cpu_to_le32(up);
 188                                 if (up == node && fnod)
 189                                         anode->btree.flags |= BP_fnode_parent;
 190                                 else
 191                                         anode->btree.flags &= ~BP_fnode_parent;
 192                                 mark_buffer_dirty(bh);
 193                                 brelse(bh);
 194                         }
 195                         return se;
 196                 }
 197                 up = up != node ? le32_to_cpu(anode->up) : -1;
 198                 btree->u.internal[btree->n_used_nodes - 1].file_secno = cpu_to_le32(/*fs*/-1);
 199                 mark_buffer_dirty(bh);
 200                 brelse(bh);
 201                 a = na;
 202                 if ((new_anode = hpfs_alloc_anode(s, a, &na, &bh))) {
 203                         anode = new_anode;
 204                         /*anode->up = cpu_to_le32(up != -1 ? up : ra);*/
 205                         anode->btree.flags |= BP_internal;
 206                         anode->btree.n_used_nodes = 1;
 207                         anode->btree.n_free_nodes = 59;
 208                         anode->btree.first_free = cpu_to_le16(16);
 209                         anode->btree.u.internal[0].down = cpu_to_le32(a);
 210                         anode->btree.u.internal[0].file_secno = cpu_to_le32(-1);
 211                         mark_buffer_dirty(bh);
 212                         brelse(bh);
 213                         if ((anode = hpfs_map_anode(s, a, &bh))) {
 214                                 anode->up = cpu_to_le32(na);
 215                                 mark_buffer_dirty(bh);
 216                                 brelse(bh);
 217                         }
 218                 } else na = a;
 219         }
 220         if ((anode = hpfs_map_anode(s, na, &bh))) {
 221                 anode->up = cpu_to_le32(node);
 222                 if (fnod)
 223                         anode->btree.flags |= BP_fnode_parent;
 224                 mark_buffer_dirty(bh);
 225                 brelse(bh);
 226         }
 227         if (!fnod) {
 228                 if (!(anode = hpfs_map_anode(s, node, &bh))) {
 229                         brelse(bh2);
 230                         return -1;
 231                 }
 232                 btree = &anode->btree;
 233         } else {
 234                 if (!(fnode = hpfs_map_fnode(s, node, &bh))) {
 235                         brelse(bh2);
 236                         return -1;
 237                 }
 238                 btree = &fnode->btree;
 239         }
 240         ranode->up = cpu_to_le32(node);
 241         memcpy(&ranode->btree, btree, le16_to_cpu(btree->first_free));
 242         if (fnod)
 243                 ranode->btree.flags |= BP_fnode_parent;
 244         ranode->btree.n_free_nodes = (bp_internal(&ranode->btree) ? 60 : 40) - ranode->btree.n_used_nodes;
 245         if (bp_internal(&ranode->btree)) for (n = 0; n < ranode->btree.n_used_nodes; n++) {
 246                 struct anode *unode;
 247                 if ((unode = hpfs_map_anode(s, le32_to_cpu(ranode->u.internal[n].down), &bh1))) {
 248                         unode->up = cpu_to_le32(ra);
 249                         unode->btree.flags &= ~BP_fnode_parent;
 250                         mark_buffer_dirty(bh1);
 251                         brelse(bh1);
 252                 }
 253         }
 254         btree->flags |= BP_internal;
 255         btree->n_free_nodes = fnod ? 10 : 58;
 256         btree->n_used_nodes = 2;
 257         btree->first_free = cpu_to_le16((char *)&btree->u.internal[2] - (char *)btree);
 258         btree->u.internal[0].file_secno = cpu_to_le32(fs);
 259         btree->u.internal[0].down = cpu_to_le32(ra);
 260         btree->u.internal[1].file_secno = cpu_to_le32(-1);
 261         btree->u.internal[1].down = cpu_to_le32(na);
 262         mark_buffer_dirty(bh);
 263         brelse(bh);
 264         mark_buffer_dirty(bh2);
 265         brelse(bh2);
 266         return se;
 267 }
 268
 269 /*
 270  * Remove allocation tree. Recursion would look much nicer but
 271  * I want to avoid it because it can cause stack overflow.
 272  */
 273
 274 void hpfs_remove_btree(struct super_block *s, struct bplus_header *btree)
 275 {
 276         struct bplus_header *btree1 = btree;
 277         struct anode *anode = NULL;
 278         anode_secno ano = 0, oano;
 279         struct buffer_head *bh;
 280         int level = 0;
 281         int pos = 0;
 282         int i;
 283         int c1, c2 = 0;
 284         int d1, d2;
 285         go_down:
 286         d2 = 0;
 287         while (bp_internal(btree1)) {
 288                 ano = le32_to_cpu(btree1->u.internal[pos].down);
 289                 if (level) brelse(bh);
 290                 if (hpfs_sb(s)->sb_chk)
 291                         if (hpfs_stop_cycles(s, ano, &d1, &d2, "hpfs_remove_btree #1"))
 292                                 return;
 293                 if (!(anode = hpfs_map_anode(s, ano, &bh))) return;
 294                 btree1 = &anode->btree;
 295                 level++;
 296                 pos = 0;
 297         }
 298         for (i = 0; i < btree1->n_used_nodes; i++)
 299                 hpfs_free_sectors(s, le32_to_cpu(btree1->u.external[i].disk_secno), le32_to_cpu(btree1->u.external[i].length));
 300         go_up:
 301         if (!level) return;
 302         brelse(bh);
 303         if (hpfs_sb(s)->sb_chk)
 304                 if (hpfs_stop_cycles(s, ano, &c1, &c2, "hpfs_remove_btree #2")) return;
 305         hpfs_free_sectors(s, ano, 1);
 306         oano = ano;
 307         ano = le32_to_cpu(anode->up);
 308         if (--level) {
 309                 if (!(anode = hpfs_map_anode(s, ano, &bh))) return;
 310                 btree1 = &anode->btree;
 311         } else btree1 = btree;
 312         for (i = 0; i < btree1->n_used_nodes; i++) {
 313                 if (le32_to_cpu(btree1->u.internal[i].down) == oano) {
 314                         if ((pos = i + 1) < btree1->n_used_nodes)
 315                                 goto go_down;
 316                         else
 317                                 goto go_up;
 318                 }
 319         }
 320         hpfs_error(s,
 321                    "reference to anode %08x not found in anode %08x "
 322                    "(probably bad up pointer)",
 323                    oano, level ? ano : -1);
 324         if (level)
 325                 brelse(bh);
 326 }
 327
 328 /* Just a wrapper around hpfs_bplus_lookup .. used for reading eas */
 329
 330 static secno anode_lookup(struct super_block *s, anode_secno a, unsigned sec)
 331 {
 332         struct anode *anode;
 333         struct buffer_head *bh;
 334         if (!(anode = hpfs_map_anode(s, a, &bh))) return -1;
 335         return hpfs_bplus_lookup(s, NULL, &anode->btree, sec, bh);
 336 }
 337
 338 int hpfs_ea_read(struct super_block *s, secno a, int ano, unsigned pos,
 339             unsigned len, char *buf)
 340 {
 341         struct buffer_head *bh;
 342         char *data;
 343         secno sec;
 344         unsigned l;
 345         while (len) {
 346                 if (ano) {
 347                         if ((sec = anode_lookup(s, a, pos >> 9)) == -1)
 348                                 return -1;
 349                 } else sec = a + (pos >> 9);
 350                 if (hpfs_sb(s)->sb_chk) if (hpfs_chk_sectors(s, sec, 1, "ea #1")) return -1;
 351                 if (!(data = hpfs_map_sector(s, sec, &bh, (len - 1) >> 9)))
 352                         return -1;
 353                 l = 0x200 - (pos & 0x1ff); if (l > len) l = len;
 354                 memcpy(buf, data + (pos & 0x1ff), l);
 355                 brelse(bh);
 356                 buf += l; pos += l; len -= l;
 357         }
 358         return 0;
 359 }
 360
 361 int hpfs_ea_write(struct super_block *s, secno a, int ano, unsigned pos,
 362              unsigned len, const char *buf)
 363 {
 364         struct buffer_head *bh;
 365         char *data;
 366         secno sec;
 367         unsigned l;
 368         while (len) {
 369                 if (ano) {
 370                         if ((sec = anode_lookup(s, a, pos >> 9)) == -1)
 371                                 return -1;
 372                 } else sec = a + (pos >> 9);
 373                 if (hpfs_sb(s)->sb_chk) if (hpfs_chk_sectors(s, sec, 1, "ea #2")) return -1;
 374                 if (!(data = hpfs_map_sector(s, sec, &bh, (len - 1) >> 9)))
 375                         return -1;
 376                 l = 0x200 - (pos & 0x1ff); if (l > len) l = len;
 377                 memcpy(data + (pos & 0x1ff), buf, l);
 378                 mark_buffer_dirty(bh);
 379                 brelse(bh);
 380                 buf += l; pos += l; len -= l;
 381         }
 382         return 0;
 383 }
 384
 385 void hpfs_ea_remove(struct super_block *s, secno a, int ano, unsigned len)
 386 {
 387         struct anode *anode;
 388         struct buffer_head *bh;
 389         if (ano) {
 390                 if (!(anode = hpfs_map_anode(s, a, &bh))) return;
 391                 hpfs_remove_btree(s, &anode->btree);
 392                 brelse(bh);
 393                 hpfs_free_sectors(s, a, 1);
 394         } else hpfs_free_sectors(s, a, (len + 511) >> 9);
 395 }
 396
 397 /* Truncate allocation tree. Doesn't join anodes - I hope it doesn't matter */
 398
 399 void hpfs_truncate_btree(struct super_block *s, secno f, int fno, unsigned secs)
 400 {
 401         struct fnode *fnode;
 402         struct anode *anode;
 403         struct buffer_head *bh;
 404         struct bplus_header *btree;
 405         anode_secno node = f;
 406         int i, j, nodes;
 407         int c1, c2 = 0;
 408         if (fno) {
 409                 if (!(fnode = hpfs_map_fnode(s, f, &bh))) return;
 410                 btree = &fnode->btree;
 411         } else {
 412                 if (!(anode = hpfs_map_anode(s, f, &bh))) return;
 413                 btree = &anode->btree;
 414         }
 415         if (!secs) {
 416                 hpfs_remove_btree(s, btree);
 417                 if (fno) {
 418                         btree->n_free_nodes = 8;
 419                         btree->n_used_nodes = 0;
 420                         btree->first_free = cpu_to_le16(8);
 421                         btree->flags &= ~BP_internal;
 422                         mark_buffer_dirty(bh);
 423                 } else hpfs_free_sectors(s, f, 1);
 424                 brelse(bh);
 425                 return;
 426         }
 427         while (bp_internal(btree)) {
 428                 nodes = btree->n_used_nodes + btree->n_free_nodes;
 429                 for (i = 0; i < btree->n_used_nodes; i++)
 430                         if (le32_to_cpu(btree->u.internal[i].file_secno) >= secs) goto f;
 431                 brelse(bh);
 432                 hpfs_error(s, "internal btree %08x doesn't end with -1", node);
 433                 return;
 434                 f:
 435                 for (j = i + 1; j < btree->n_used_nodes; j++)
 436                         hpfs_ea_remove(s, le32_to_cpu(btree->u.internal[j].down), 1, 0);
 437                 btree->n_used_nodes = i + 1;
 438                 btree->n_free_nodes = nodes - btree->n_used_nodes;
 439                 btree->first_free = cpu_to_le16(8 + 8 * btree->n_used_nodes);
 440                 mark_buffer_dirty(bh);
 441                 if (btree->u.internal[i].file_secno == cpu_to_le32(secs)) {
 442                         brelse(bh);
 443                         return;
 444                 }
 445                 node = le32_to_cpu(btree->u.internal[i].down);
 446                 brelse(bh);
 447                 if (hpfs_sb(s)->sb_chk)
 448                         if (hpfs_stop_cycles(s, node, &c1, &c2, "hpfs_truncate_btree"))
 449                                 return;
 450                 if (!(anode = hpfs_map_anode(s, node, &bh))) return;
 451                 btree = &anode->btree;
 452         }
 453         nodes = btree->n_used_nodes + btree->n_free_nodes;
 454         for (i = 0; i < btree->n_used_nodes; i++)
 455                 if (le32_to_cpu(btree->u.external[i].file_secno) + le32_to_cpu(btree->u.external[i].length) >= secs) goto ff;
 456         brelse(bh);
 457         return;
 458         ff:
 459         if (secs <= le32_to_cpu(btree->u.external[i].file_secno)) {
 460                 hpfs_error(s, "there is an allocation error in file %08x, sector %08x", f, secs);
 461                 if (i) i--;
 462         }
 463         else if (le32_to_cpu(btree->u.external[i].file_secno) + le32_to_cpu(btree->u.external[i].length) > secs) {
 464                 hpfs_free_sectors(s, le32_to_cpu(btree->u.external[i].disk_secno) + secs -
 465                         le32_to_cpu(btree->u.external[i].file_secno), le32_to_cpu(btree->u.external[i].length)
 466                         - secs + le32_to_cpu(btree->u.external[i].file_secno)); /* I hope gcc optimizes this :-) */
 467                 btree->u.external[i].length = cpu_to_le32(secs - le32_to_cpu(btree->u.external[i].file_secno));
 468         }
 469         for (j = i + 1; j < btree->n_used_nodes; j++)
 470                 hpfs_free_sectors(s, le32_to_cpu(btree->u.external[j].disk_secno), le32_to_cpu(btree->u.external[j].length));
 471         btree->n_used_nodes = i + 1;
 472         btree->n_free_nodes = nodes - btree->n_used_nodes;
 473         btree->first_free = cpu_to_le16(8 + 12 * btree->n_used_nodes);
 474         mark_buffer_dirty(bh);
 475         brelse(bh);
 476 }
 477
 478 /* Remove file or directory and it's eas - note that directory must
 479    be empty when this is called. */
 480
 481 void hpfs_remove_fnode(struct super_block *s, fnode_secno fno)
 482 {
 483         struct buffer_head *bh;
 484         struct fnode *fnode;
 485         struct extended_attribute *ea;
 486         struct extended_attribute *ea_end;
 487         if (!(fnode = hpfs_map_fnode(s, fno, &bh))) return;
 488         if (!fnode_is_dir(fnode)) hpfs_remove_btree(s, &fnode->btree);
 489         else hpfs_remove_dtree(s, le32_to_cpu(fnode->u.external[0].disk_secno));
 490         ea_end = fnode_end_ea(fnode);
 491         for (ea = fnode_ea(fnode); ea < ea_end; ea = next_ea(ea))
 492                 if (ea_indirect(ea))
 493                         hpfs_ea_remove(s, ea_sec(ea), ea_in_anode(ea), ea_len(ea));
 494         hpfs_ea_ext_remove(s, le32_to_cpu(fnode->ea_secno), fnode_in_anode(fnode), le32_to_cpu(fnode->ea_size_l));
 495         brelse(bh);
 496         hpfs_free_sectors(s, fno, 1);
 497 }