fs/hpfs/anode.c

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