| 1 | /* |
| 2 | * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc. |
| 3 | * All Rights Reserved. |
| 4 | * |
| 5 | * This program is free software; you can redistribute it and/or |
| 6 | * modify it under the terms of the GNU General Public License as |
| 7 | * published by the Free Software Foundation. |
| 8 | * |
| 9 | * This program is distributed in the hope that it would be useful, |
| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 12 | * GNU General Public License for more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU General Public License |
| 15 | * along with this program; if not, write the Free Software Foundation, |
| 16 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
| 17 | */ |
| 18 | #include "xfs.h" |
| 19 | #include "xfs_fs.h" |
| 20 | #include "xfs_types.h" |
| 21 | #include "xfs_log.h" |
| 22 | #include "xfs_trans.h" |
| 23 | #include "xfs_sb.h" |
| 24 | #include "xfs_ag.h" |
| 25 | #include "xfs_mount.h" |
| 26 | #include "xfs_da_btree.h" |
| 27 | #include "xfs_bmap_btree.h" |
| 28 | #include "xfs_dinode.h" |
| 29 | #include "xfs_inode.h" |
| 30 | #include "xfs_dir2_format.h" |
| 31 | #include "xfs_dir2_priv.h" |
| 32 | #include "xfs_error.h" |
| 33 | |
| 34 | STATIC xfs_dir2_data_free_t * |
| 35 | xfs_dir2_data_freefind(xfs_dir2_data_hdr_t *hdr, xfs_dir2_data_unused_t *dup); |
| 36 | |
| 37 | #ifdef DEBUG |
| 38 | /* |
| 39 | * Check the consistency of the data block. |
| 40 | * The input can also be a block-format directory. |
| 41 | * Pop an assert if we find anything bad. |
| 42 | */ |
| 43 | void |
| 44 | xfs_dir2_data_check( |
| 45 | xfs_inode_t *dp, /* incore inode pointer */ |
| 46 | xfs_dabuf_t *bp) /* data block's buffer */ |
| 47 | { |
| 48 | xfs_dir2_dataptr_t addr; /* addr for leaf lookup */ |
| 49 | xfs_dir2_data_free_t *bf; /* bestfree table */ |
| 50 | xfs_dir2_block_tail_t *btp=NULL; /* block tail */ |
| 51 | int count; /* count of entries found */ |
| 52 | xfs_dir2_data_hdr_t *hdr; /* data block header */ |
| 53 | xfs_dir2_data_entry_t *dep; /* data entry */ |
| 54 | xfs_dir2_data_free_t *dfp; /* bestfree entry */ |
| 55 | xfs_dir2_data_unused_t *dup; /* unused entry */ |
| 56 | char *endp; /* end of useful data */ |
| 57 | int freeseen; /* mask of bestfrees seen */ |
| 58 | xfs_dahash_t hash; /* hash of current name */ |
| 59 | int i; /* leaf index */ |
| 60 | int lastfree; /* last entry was unused */ |
| 61 | xfs_dir2_leaf_entry_t *lep=NULL; /* block leaf entries */ |
| 62 | xfs_mount_t *mp; /* filesystem mount point */ |
| 63 | char *p; /* current data position */ |
| 64 | int stale; /* count of stale leaves */ |
| 65 | struct xfs_name name; |
| 66 | |
| 67 | mp = dp->i_mount; |
| 68 | hdr = bp->data; |
| 69 | bf = hdr->bestfree; |
| 70 | p = (char *)(hdr + 1); |
| 71 | |
| 72 | if (hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC)) { |
| 73 | btp = xfs_dir2_block_tail_p(mp, hdr); |
| 74 | lep = xfs_dir2_block_leaf_p(btp); |
| 75 | endp = (char *)lep; |
| 76 | } else { |
| 77 | ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC)); |
| 78 | endp = (char *)hdr + mp->m_dirblksize; |
| 79 | } |
| 80 | |
| 81 | count = lastfree = freeseen = 0; |
| 82 | /* |
| 83 | * Account for zero bestfree entries. |
| 84 | */ |
| 85 | if (!bf[0].length) { |
| 86 | ASSERT(!bf[0].offset); |
| 87 | freeseen |= 1 << 0; |
| 88 | } |
| 89 | if (!bf[1].length) { |
| 90 | ASSERT(!bf[1].offset); |
| 91 | freeseen |= 1 << 1; |
| 92 | } |
| 93 | if (!bf[2].length) { |
| 94 | ASSERT(!bf[2].offset); |
| 95 | freeseen |= 1 << 2; |
| 96 | } |
| 97 | ASSERT(be16_to_cpu(bf[0].length) >= be16_to_cpu(bf[1].length)); |
| 98 | ASSERT(be16_to_cpu(bf[1].length) >= be16_to_cpu(bf[2].length)); |
| 99 | /* |
| 100 | * Loop over the data/unused entries. |
| 101 | */ |
| 102 | while (p < endp) { |
| 103 | dup = (xfs_dir2_data_unused_t *)p; |
| 104 | /* |
| 105 | * If it's unused, look for the space in the bestfree table. |
| 106 | * If we find it, account for that, else make sure it |
| 107 | * doesn't need to be there. |
| 108 | */ |
| 109 | if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) { |
| 110 | ASSERT(lastfree == 0); |
| 111 | ASSERT(be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup)) == |
| 112 | (char *)dup - (char *)hdr); |
| 113 | dfp = xfs_dir2_data_freefind(hdr, dup); |
| 114 | if (dfp) { |
| 115 | i = (int)(dfp - bf); |
| 116 | ASSERT((freeseen & (1 << i)) == 0); |
| 117 | freeseen |= 1 << i; |
| 118 | } else { |
| 119 | ASSERT(be16_to_cpu(dup->length) <= |
| 120 | be16_to_cpu(bf[2].length)); |
| 121 | } |
| 122 | p += be16_to_cpu(dup->length); |
| 123 | lastfree = 1; |
| 124 | continue; |
| 125 | } |
| 126 | /* |
| 127 | * It's a real entry. Validate the fields. |
| 128 | * If this is a block directory then make sure it's |
| 129 | * in the leaf section of the block. |
| 130 | * The linear search is crude but this is DEBUG code. |
| 131 | */ |
| 132 | dep = (xfs_dir2_data_entry_t *)p; |
| 133 | ASSERT(dep->namelen != 0); |
| 134 | ASSERT(xfs_dir_ino_validate(mp, be64_to_cpu(dep->inumber)) == 0); |
| 135 | ASSERT(be16_to_cpu(*xfs_dir2_data_entry_tag_p(dep)) == |
| 136 | (char *)dep - (char *)hdr); |
| 137 | count++; |
| 138 | lastfree = 0; |
| 139 | if (hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC)) { |
| 140 | addr = xfs_dir2_db_off_to_dataptr(mp, mp->m_dirdatablk, |
| 141 | (xfs_dir2_data_aoff_t) |
| 142 | ((char *)dep - (char *)hdr)); |
| 143 | name.name = dep->name; |
| 144 | name.len = dep->namelen; |
| 145 | hash = mp->m_dirnameops->hashname(&name); |
| 146 | for (i = 0; i < be32_to_cpu(btp->count); i++) { |
| 147 | if (be32_to_cpu(lep[i].address) == addr && |
| 148 | be32_to_cpu(lep[i].hashval) == hash) |
| 149 | break; |
| 150 | } |
| 151 | ASSERT(i < be32_to_cpu(btp->count)); |
| 152 | } |
| 153 | p += xfs_dir2_data_entsize(dep->namelen); |
| 154 | } |
| 155 | /* |
| 156 | * Need to have seen all the entries and all the bestfree slots. |
| 157 | */ |
| 158 | ASSERT(freeseen == 7); |
| 159 | if (hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC)) { |
| 160 | for (i = stale = 0; i < be32_to_cpu(btp->count); i++) { |
| 161 | if (lep[i].address == |
| 162 | cpu_to_be32(XFS_DIR2_NULL_DATAPTR)) |
| 163 | stale++; |
| 164 | if (i > 0) |
| 165 | ASSERT(be32_to_cpu(lep[i].hashval) >= be32_to_cpu(lep[i - 1].hashval)); |
| 166 | } |
| 167 | ASSERT(count == be32_to_cpu(btp->count) - be32_to_cpu(btp->stale)); |
| 168 | ASSERT(stale == be32_to_cpu(btp->stale)); |
| 169 | } |
| 170 | } |
| 171 | #endif |
| 172 | |
| 173 | /* |
| 174 | * Given a data block and an unused entry from that block, |
| 175 | * return the bestfree entry if any that corresponds to it. |
| 176 | */ |
| 177 | STATIC xfs_dir2_data_free_t * |
| 178 | xfs_dir2_data_freefind( |
| 179 | xfs_dir2_data_hdr_t *hdr, /* data block */ |
| 180 | xfs_dir2_data_unused_t *dup) /* data unused entry */ |
| 181 | { |
| 182 | xfs_dir2_data_free_t *dfp; /* bestfree entry */ |
| 183 | xfs_dir2_data_aoff_t off; /* offset value needed */ |
| 184 | #if defined(DEBUG) && defined(__KERNEL__) |
| 185 | int matched; /* matched the value */ |
| 186 | int seenzero; /* saw a 0 bestfree entry */ |
| 187 | #endif |
| 188 | |
| 189 | off = (xfs_dir2_data_aoff_t)((char *)dup - (char *)hdr); |
| 190 | #if defined(DEBUG) && defined(__KERNEL__) |
| 191 | /* |
| 192 | * Validate some consistency in the bestfree table. |
| 193 | * Check order, non-overlapping entries, and if we find the |
| 194 | * one we're looking for it has to be exact. |
| 195 | */ |
| 196 | ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) || |
| 197 | hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC)); |
| 198 | for (dfp = &hdr->bestfree[0], seenzero = matched = 0; |
| 199 | dfp < &hdr->bestfree[XFS_DIR2_DATA_FD_COUNT]; |
| 200 | dfp++) { |
| 201 | if (!dfp->offset) { |
| 202 | ASSERT(!dfp->length); |
| 203 | seenzero = 1; |
| 204 | continue; |
| 205 | } |
| 206 | ASSERT(seenzero == 0); |
| 207 | if (be16_to_cpu(dfp->offset) == off) { |
| 208 | matched = 1; |
| 209 | ASSERT(dfp->length == dup->length); |
| 210 | } else if (off < be16_to_cpu(dfp->offset)) |
| 211 | ASSERT(off + be16_to_cpu(dup->length) <= be16_to_cpu(dfp->offset)); |
| 212 | else |
| 213 | ASSERT(be16_to_cpu(dfp->offset) + be16_to_cpu(dfp->length) <= off); |
| 214 | ASSERT(matched || be16_to_cpu(dfp->length) >= be16_to_cpu(dup->length)); |
| 215 | if (dfp > &hdr->bestfree[0]) |
| 216 | ASSERT(be16_to_cpu(dfp[-1].length) >= be16_to_cpu(dfp[0].length)); |
| 217 | } |
| 218 | #endif |
| 219 | /* |
| 220 | * If this is smaller than the smallest bestfree entry, |
| 221 | * it can't be there since they're sorted. |
| 222 | */ |
| 223 | if (be16_to_cpu(dup->length) < |
| 224 | be16_to_cpu(hdr->bestfree[XFS_DIR2_DATA_FD_COUNT - 1].length)) |
| 225 | return NULL; |
| 226 | /* |
| 227 | * Look at the three bestfree entries for our guy. |
| 228 | */ |
| 229 | for (dfp = &hdr->bestfree[0]; |
| 230 | dfp < &hdr->bestfree[XFS_DIR2_DATA_FD_COUNT]; |
| 231 | dfp++) { |
| 232 | if (!dfp->offset) |
| 233 | return NULL; |
| 234 | if (be16_to_cpu(dfp->offset) == off) |
| 235 | return dfp; |
| 236 | } |
| 237 | /* |
| 238 | * Didn't find it. This only happens if there are duplicate lengths. |
| 239 | */ |
| 240 | return NULL; |
| 241 | } |
| 242 | |
| 243 | /* |
| 244 | * Insert an unused-space entry into the bestfree table. |
| 245 | */ |
| 246 | xfs_dir2_data_free_t * /* entry inserted */ |
| 247 | xfs_dir2_data_freeinsert( |
| 248 | xfs_dir2_data_hdr_t *hdr, /* data block pointer */ |
| 249 | xfs_dir2_data_unused_t *dup, /* unused space */ |
| 250 | int *loghead) /* log the data header (out) */ |
| 251 | { |
| 252 | xfs_dir2_data_free_t *dfp; /* bestfree table pointer */ |
| 253 | xfs_dir2_data_free_t new; /* new bestfree entry */ |
| 254 | |
| 255 | #ifdef __KERNEL__ |
| 256 | ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) || |
| 257 | hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC)); |
| 258 | #endif |
| 259 | dfp = hdr->bestfree; |
| 260 | new.length = dup->length; |
| 261 | new.offset = cpu_to_be16((char *)dup - (char *)hdr); |
| 262 | |
| 263 | /* |
| 264 | * Insert at position 0, 1, or 2; or not at all. |
| 265 | */ |
| 266 | if (be16_to_cpu(new.length) > be16_to_cpu(dfp[0].length)) { |
| 267 | dfp[2] = dfp[1]; |
| 268 | dfp[1] = dfp[0]; |
| 269 | dfp[0] = new; |
| 270 | *loghead = 1; |
| 271 | return &dfp[0]; |
| 272 | } |
| 273 | if (be16_to_cpu(new.length) > be16_to_cpu(dfp[1].length)) { |
| 274 | dfp[2] = dfp[1]; |
| 275 | dfp[1] = new; |
| 276 | *loghead = 1; |
| 277 | return &dfp[1]; |
| 278 | } |
| 279 | if (be16_to_cpu(new.length) > be16_to_cpu(dfp[2].length)) { |
| 280 | dfp[2] = new; |
| 281 | *loghead = 1; |
| 282 | return &dfp[2]; |
| 283 | } |
| 284 | return NULL; |
| 285 | } |
| 286 | |
| 287 | /* |
| 288 | * Remove a bestfree entry from the table. |
| 289 | */ |
| 290 | STATIC void |
| 291 | xfs_dir2_data_freeremove( |
| 292 | xfs_dir2_data_hdr_t *hdr, /* data block header */ |
| 293 | xfs_dir2_data_free_t *dfp, /* bestfree entry pointer */ |
| 294 | int *loghead) /* out: log data header */ |
| 295 | { |
| 296 | #ifdef __KERNEL__ |
| 297 | ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) || |
| 298 | hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC)); |
| 299 | #endif |
| 300 | /* |
| 301 | * It's the first entry, slide the next 2 up. |
| 302 | */ |
| 303 | if (dfp == &hdr->bestfree[0]) { |
| 304 | hdr->bestfree[0] = hdr->bestfree[1]; |
| 305 | hdr->bestfree[1] = hdr->bestfree[2]; |
| 306 | } |
| 307 | /* |
| 308 | * It's the second entry, slide the 3rd entry up. |
| 309 | */ |
| 310 | else if (dfp == &hdr->bestfree[1]) |
| 311 | hdr->bestfree[1] = hdr->bestfree[2]; |
| 312 | /* |
| 313 | * Must be the last entry. |
| 314 | */ |
| 315 | else |
| 316 | ASSERT(dfp == &hdr->bestfree[2]); |
| 317 | /* |
| 318 | * Clear the 3rd entry, must be zero now. |
| 319 | */ |
| 320 | hdr->bestfree[2].length = 0; |
| 321 | hdr->bestfree[2].offset = 0; |
| 322 | *loghead = 1; |
| 323 | } |
| 324 | |
| 325 | /* |
| 326 | * Given a data block, reconstruct its bestfree map. |
| 327 | */ |
| 328 | void |
| 329 | xfs_dir2_data_freescan( |
| 330 | xfs_mount_t *mp, /* filesystem mount point */ |
| 331 | xfs_dir2_data_hdr_t *hdr, /* data block header */ |
| 332 | int *loghead) /* out: log data header */ |
| 333 | { |
| 334 | xfs_dir2_block_tail_t *btp; /* block tail */ |
| 335 | xfs_dir2_data_entry_t *dep; /* active data entry */ |
| 336 | xfs_dir2_data_unused_t *dup; /* unused data entry */ |
| 337 | char *endp; /* end of block's data */ |
| 338 | char *p; /* current entry pointer */ |
| 339 | |
| 340 | #ifdef __KERNEL__ |
| 341 | ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) || |
| 342 | hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC)); |
| 343 | #endif |
| 344 | /* |
| 345 | * Start by clearing the table. |
| 346 | */ |
| 347 | memset(hdr->bestfree, 0, sizeof(hdr->bestfree)); |
| 348 | *loghead = 1; |
| 349 | /* |
| 350 | * Set up pointers. |
| 351 | */ |
| 352 | p = (char *)(hdr + 1); |
| 353 | if (hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC)) { |
| 354 | btp = xfs_dir2_block_tail_p(mp, hdr); |
| 355 | endp = (char *)xfs_dir2_block_leaf_p(btp); |
| 356 | } else |
| 357 | endp = (char *)hdr + mp->m_dirblksize; |
| 358 | /* |
| 359 | * Loop over the block's entries. |
| 360 | */ |
| 361 | while (p < endp) { |
| 362 | dup = (xfs_dir2_data_unused_t *)p; |
| 363 | /* |
| 364 | * If it's a free entry, insert it. |
| 365 | */ |
| 366 | if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) { |
| 367 | ASSERT((char *)dup - (char *)hdr == |
| 368 | be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup))); |
| 369 | xfs_dir2_data_freeinsert(hdr, dup, loghead); |
| 370 | p += be16_to_cpu(dup->length); |
| 371 | } |
| 372 | /* |
| 373 | * For active entries, check their tags and skip them. |
| 374 | */ |
| 375 | else { |
| 376 | dep = (xfs_dir2_data_entry_t *)p; |
| 377 | ASSERT((char *)dep - (char *)hdr == |
| 378 | be16_to_cpu(*xfs_dir2_data_entry_tag_p(dep))); |
| 379 | p += xfs_dir2_data_entsize(dep->namelen); |
| 380 | } |
| 381 | } |
| 382 | } |
| 383 | |
| 384 | /* |
| 385 | * Initialize a data block at the given block number in the directory. |
| 386 | * Give back the buffer for the created block. |
| 387 | */ |
| 388 | int /* error */ |
| 389 | xfs_dir2_data_init( |
| 390 | xfs_da_args_t *args, /* directory operation args */ |
| 391 | xfs_dir2_db_t blkno, /* logical dir block number */ |
| 392 | xfs_dabuf_t **bpp) /* output block buffer */ |
| 393 | { |
| 394 | xfs_dabuf_t *bp; /* block buffer */ |
| 395 | xfs_dir2_data_hdr_t *hdr; /* data block header */ |
| 396 | xfs_inode_t *dp; /* incore directory inode */ |
| 397 | xfs_dir2_data_unused_t *dup; /* unused entry pointer */ |
| 398 | int error; /* error return value */ |
| 399 | int i; /* bestfree index */ |
| 400 | xfs_mount_t *mp; /* filesystem mount point */ |
| 401 | xfs_trans_t *tp; /* transaction pointer */ |
| 402 | int t; /* temp */ |
| 403 | |
| 404 | dp = args->dp; |
| 405 | mp = dp->i_mount; |
| 406 | tp = args->trans; |
| 407 | /* |
| 408 | * Get the buffer set up for the block. |
| 409 | */ |
| 410 | error = xfs_da_get_buf(tp, dp, xfs_dir2_db_to_da(mp, blkno), -1, &bp, |
| 411 | XFS_DATA_FORK); |
| 412 | if (error) { |
| 413 | return error; |
| 414 | } |
| 415 | ASSERT(bp != NULL); |
| 416 | |
| 417 | /* |
| 418 | * Initialize the header. |
| 419 | */ |
| 420 | hdr = bp->data; |
| 421 | hdr->magic = cpu_to_be32(XFS_DIR2_DATA_MAGIC); |
| 422 | hdr->bestfree[0].offset = cpu_to_be16(sizeof(*hdr)); |
| 423 | for (i = 1; i < XFS_DIR2_DATA_FD_COUNT; i++) { |
| 424 | hdr->bestfree[i].length = 0; |
| 425 | hdr->bestfree[i].offset = 0; |
| 426 | } |
| 427 | |
| 428 | /* |
| 429 | * Set up an unused entry for the block's body. |
| 430 | */ |
| 431 | dup = (xfs_dir2_data_unused_t *)(hdr + 1); |
| 432 | dup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG); |
| 433 | |
| 434 | t = mp->m_dirblksize - (uint)sizeof(*hdr); |
| 435 | hdr->bestfree[0].length = cpu_to_be16(t); |
| 436 | dup->length = cpu_to_be16(t); |
| 437 | *xfs_dir2_data_unused_tag_p(dup) = cpu_to_be16((char *)dup - (char *)hdr); |
| 438 | /* |
| 439 | * Log it and return it. |
| 440 | */ |
| 441 | xfs_dir2_data_log_header(tp, bp); |
| 442 | xfs_dir2_data_log_unused(tp, bp, dup); |
| 443 | *bpp = bp; |
| 444 | return 0; |
| 445 | } |
| 446 | |
| 447 | /* |
| 448 | * Log an active data entry from the block. |
| 449 | */ |
| 450 | void |
| 451 | xfs_dir2_data_log_entry( |
| 452 | xfs_trans_t *tp, /* transaction pointer */ |
| 453 | xfs_dabuf_t *bp, /* block buffer */ |
| 454 | xfs_dir2_data_entry_t *dep) /* data entry pointer */ |
| 455 | { |
| 456 | xfs_dir2_data_hdr_t *hdr = bp->data; |
| 457 | |
| 458 | ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) || |
| 459 | hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC)); |
| 460 | |
| 461 | xfs_da_log_buf(tp, bp, (uint)((char *)dep - (char *)hdr), |
| 462 | (uint)((char *)(xfs_dir2_data_entry_tag_p(dep) + 1) - |
| 463 | (char *)hdr - 1)); |
| 464 | } |
| 465 | |
| 466 | /* |
| 467 | * Log a data block header. |
| 468 | */ |
| 469 | void |
| 470 | xfs_dir2_data_log_header( |
| 471 | xfs_trans_t *tp, /* transaction pointer */ |
| 472 | xfs_dabuf_t *bp) /* block buffer */ |
| 473 | { |
| 474 | xfs_dir2_data_hdr_t *hdr = bp->data; |
| 475 | |
| 476 | ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) || |
| 477 | hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC)); |
| 478 | |
| 479 | xfs_da_log_buf(tp, bp, 0, sizeof(*hdr) - 1); |
| 480 | } |
| 481 | |
| 482 | /* |
| 483 | * Log a data unused entry. |
| 484 | */ |
| 485 | void |
| 486 | xfs_dir2_data_log_unused( |
| 487 | xfs_trans_t *tp, /* transaction pointer */ |
| 488 | xfs_dabuf_t *bp, /* block buffer */ |
| 489 | xfs_dir2_data_unused_t *dup) /* data unused pointer */ |
| 490 | { |
| 491 | xfs_dir2_data_hdr_t *hdr = bp->data; |
| 492 | |
| 493 | ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) || |
| 494 | hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC)); |
| 495 | |
| 496 | /* |
| 497 | * Log the first part of the unused entry. |
| 498 | */ |
| 499 | xfs_da_log_buf(tp, bp, (uint)((char *)dup - (char *)hdr), |
| 500 | (uint)((char *)&dup->length + sizeof(dup->length) - |
| 501 | 1 - (char *)hdr)); |
| 502 | /* |
| 503 | * Log the end (tag) of the unused entry. |
| 504 | */ |
| 505 | xfs_da_log_buf(tp, bp, |
| 506 | (uint)((char *)xfs_dir2_data_unused_tag_p(dup) - (char *)hdr), |
| 507 | (uint)((char *)xfs_dir2_data_unused_tag_p(dup) - (char *)hdr + |
| 508 | sizeof(xfs_dir2_data_off_t) - 1)); |
| 509 | } |
| 510 | |
| 511 | /* |
| 512 | * Make a byte range in the data block unused. |
| 513 | * Its current contents are unimportant. |
| 514 | */ |
| 515 | void |
| 516 | xfs_dir2_data_make_free( |
| 517 | xfs_trans_t *tp, /* transaction pointer */ |
| 518 | xfs_dabuf_t *bp, /* block buffer */ |
| 519 | xfs_dir2_data_aoff_t offset, /* starting byte offset */ |
| 520 | xfs_dir2_data_aoff_t len, /* length in bytes */ |
| 521 | int *needlogp, /* out: log header */ |
| 522 | int *needscanp) /* out: regen bestfree */ |
| 523 | { |
| 524 | xfs_dir2_data_hdr_t *hdr; /* data block pointer */ |
| 525 | xfs_dir2_data_free_t *dfp; /* bestfree pointer */ |
| 526 | char *endptr; /* end of data area */ |
| 527 | xfs_mount_t *mp; /* filesystem mount point */ |
| 528 | int needscan; /* need to regen bestfree */ |
| 529 | xfs_dir2_data_unused_t *newdup; /* new unused entry */ |
| 530 | xfs_dir2_data_unused_t *postdup; /* unused entry after us */ |
| 531 | xfs_dir2_data_unused_t *prevdup; /* unused entry before us */ |
| 532 | |
| 533 | mp = tp->t_mountp; |
| 534 | hdr = bp->data; |
| 535 | |
| 536 | /* |
| 537 | * Figure out where the end of the data area is. |
| 538 | */ |
| 539 | if (hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC)) |
| 540 | endptr = (char *)hdr + mp->m_dirblksize; |
| 541 | else { |
| 542 | xfs_dir2_block_tail_t *btp; /* block tail */ |
| 543 | |
| 544 | ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC)); |
| 545 | btp = xfs_dir2_block_tail_p(mp, hdr); |
| 546 | endptr = (char *)xfs_dir2_block_leaf_p(btp); |
| 547 | } |
| 548 | /* |
| 549 | * If this isn't the start of the block, then back up to |
| 550 | * the previous entry and see if it's free. |
| 551 | */ |
| 552 | if (offset > sizeof(*hdr)) { |
| 553 | __be16 *tagp; /* tag just before us */ |
| 554 | |
| 555 | tagp = (__be16 *)((char *)hdr + offset) - 1; |
| 556 | prevdup = (xfs_dir2_data_unused_t *)((char *)hdr + be16_to_cpu(*tagp)); |
| 557 | if (be16_to_cpu(prevdup->freetag) != XFS_DIR2_DATA_FREE_TAG) |
| 558 | prevdup = NULL; |
| 559 | } else |
| 560 | prevdup = NULL; |
| 561 | /* |
| 562 | * If this isn't the end of the block, see if the entry after |
| 563 | * us is free. |
| 564 | */ |
| 565 | if ((char *)hdr + offset + len < endptr) { |
| 566 | postdup = |
| 567 | (xfs_dir2_data_unused_t *)((char *)hdr + offset + len); |
| 568 | if (be16_to_cpu(postdup->freetag) != XFS_DIR2_DATA_FREE_TAG) |
| 569 | postdup = NULL; |
| 570 | } else |
| 571 | postdup = NULL; |
| 572 | ASSERT(*needscanp == 0); |
| 573 | needscan = 0; |
| 574 | /* |
| 575 | * Previous and following entries are both free, |
| 576 | * merge everything into a single free entry. |
| 577 | */ |
| 578 | if (prevdup && postdup) { |
| 579 | xfs_dir2_data_free_t *dfp2; /* another bestfree pointer */ |
| 580 | |
| 581 | /* |
| 582 | * See if prevdup and/or postdup are in bestfree table. |
| 583 | */ |
| 584 | dfp = xfs_dir2_data_freefind(hdr, prevdup); |
| 585 | dfp2 = xfs_dir2_data_freefind(hdr, postdup); |
| 586 | /* |
| 587 | * We need a rescan unless there are exactly 2 free entries |
| 588 | * namely our two. Then we know what's happening, otherwise |
| 589 | * since the third bestfree is there, there might be more |
| 590 | * entries. |
| 591 | */ |
| 592 | needscan = (hdr->bestfree[2].length != 0); |
| 593 | /* |
| 594 | * Fix up the new big freespace. |
| 595 | */ |
| 596 | be16_add_cpu(&prevdup->length, len + be16_to_cpu(postdup->length)); |
| 597 | *xfs_dir2_data_unused_tag_p(prevdup) = |
| 598 | cpu_to_be16((char *)prevdup - (char *)hdr); |
| 599 | xfs_dir2_data_log_unused(tp, bp, prevdup); |
| 600 | if (!needscan) { |
| 601 | /* |
| 602 | * Has to be the case that entries 0 and 1 are |
| 603 | * dfp and dfp2 (don't know which is which), and |
| 604 | * entry 2 is empty. |
| 605 | * Remove entry 1 first then entry 0. |
| 606 | */ |
| 607 | ASSERT(dfp && dfp2); |
| 608 | if (dfp == &hdr->bestfree[1]) { |
| 609 | dfp = &hdr->bestfree[0]; |
| 610 | ASSERT(dfp2 == dfp); |
| 611 | dfp2 = &hdr->bestfree[1]; |
| 612 | } |
| 613 | xfs_dir2_data_freeremove(hdr, dfp2, needlogp); |
| 614 | xfs_dir2_data_freeremove(hdr, dfp, needlogp); |
| 615 | /* |
| 616 | * Now insert the new entry. |
| 617 | */ |
| 618 | dfp = xfs_dir2_data_freeinsert(hdr, prevdup, needlogp); |
| 619 | ASSERT(dfp == &hdr->bestfree[0]); |
| 620 | ASSERT(dfp->length == prevdup->length); |
| 621 | ASSERT(!dfp[1].length); |
| 622 | ASSERT(!dfp[2].length); |
| 623 | } |
| 624 | } |
| 625 | /* |
| 626 | * The entry before us is free, merge with it. |
| 627 | */ |
| 628 | else if (prevdup) { |
| 629 | dfp = xfs_dir2_data_freefind(hdr, prevdup); |
| 630 | be16_add_cpu(&prevdup->length, len); |
| 631 | *xfs_dir2_data_unused_tag_p(prevdup) = |
| 632 | cpu_to_be16((char *)prevdup - (char *)hdr); |
| 633 | xfs_dir2_data_log_unused(tp, bp, prevdup); |
| 634 | /* |
| 635 | * If the previous entry was in the table, the new entry |
| 636 | * is longer, so it will be in the table too. Remove |
| 637 | * the old one and add the new one. |
| 638 | */ |
| 639 | if (dfp) { |
| 640 | xfs_dir2_data_freeremove(hdr, dfp, needlogp); |
| 641 | xfs_dir2_data_freeinsert(hdr, prevdup, needlogp); |
| 642 | } |
| 643 | /* |
| 644 | * Otherwise we need a scan if the new entry is big enough. |
| 645 | */ |
| 646 | else { |
| 647 | needscan = be16_to_cpu(prevdup->length) > |
| 648 | be16_to_cpu(hdr->bestfree[2].length); |
| 649 | } |
| 650 | } |
| 651 | /* |
| 652 | * The following entry is free, merge with it. |
| 653 | */ |
| 654 | else if (postdup) { |
| 655 | dfp = xfs_dir2_data_freefind(hdr, postdup); |
| 656 | newdup = (xfs_dir2_data_unused_t *)((char *)hdr + offset); |
| 657 | newdup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG); |
| 658 | newdup->length = cpu_to_be16(len + be16_to_cpu(postdup->length)); |
| 659 | *xfs_dir2_data_unused_tag_p(newdup) = |
| 660 | cpu_to_be16((char *)newdup - (char *)hdr); |
| 661 | xfs_dir2_data_log_unused(tp, bp, newdup); |
| 662 | /* |
| 663 | * If the following entry was in the table, the new entry |
| 664 | * is longer, so it will be in the table too. Remove |
| 665 | * the old one and add the new one. |
| 666 | */ |
| 667 | if (dfp) { |
| 668 | xfs_dir2_data_freeremove(hdr, dfp, needlogp); |
| 669 | xfs_dir2_data_freeinsert(hdr, newdup, needlogp); |
| 670 | } |
| 671 | /* |
| 672 | * Otherwise we need a scan if the new entry is big enough. |
| 673 | */ |
| 674 | else { |
| 675 | needscan = be16_to_cpu(newdup->length) > |
| 676 | be16_to_cpu(hdr->bestfree[2].length); |
| 677 | } |
| 678 | } |
| 679 | /* |
| 680 | * Neither neighbor is free. Make a new entry. |
| 681 | */ |
| 682 | else { |
| 683 | newdup = (xfs_dir2_data_unused_t *)((char *)hdr + offset); |
| 684 | newdup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG); |
| 685 | newdup->length = cpu_to_be16(len); |
| 686 | *xfs_dir2_data_unused_tag_p(newdup) = |
| 687 | cpu_to_be16((char *)newdup - (char *)hdr); |
| 688 | xfs_dir2_data_log_unused(tp, bp, newdup); |
| 689 | xfs_dir2_data_freeinsert(hdr, newdup, needlogp); |
| 690 | } |
| 691 | *needscanp = needscan; |
| 692 | } |
| 693 | |
| 694 | /* |
| 695 | * Take a byte range out of an existing unused space and make it un-free. |
| 696 | */ |
| 697 | void |
| 698 | xfs_dir2_data_use_free( |
| 699 | xfs_trans_t *tp, /* transaction pointer */ |
| 700 | xfs_dabuf_t *bp, /* data block buffer */ |
| 701 | xfs_dir2_data_unused_t *dup, /* unused entry */ |
| 702 | xfs_dir2_data_aoff_t offset, /* starting offset to use */ |
| 703 | xfs_dir2_data_aoff_t len, /* length to use */ |
| 704 | int *needlogp, /* out: need to log header */ |
| 705 | int *needscanp) /* out: need regen bestfree */ |
| 706 | { |
| 707 | xfs_dir2_data_hdr_t *hdr; /* data block header */ |
| 708 | xfs_dir2_data_free_t *dfp; /* bestfree pointer */ |
| 709 | int matchback; /* matches end of freespace */ |
| 710 | int matchfront; /* matches start of freespace */ |
| 711 | int needscan; /* need to regen bestfree */ |
| 712 | xfs_dir2_data_unused_t *newdup; /* new unused entry */ |
| 713 | xfs_dir2_data_unused_t *newdup2; /* another new unused entry */ |
| 714 | int oldlen; /* old unused entry's length */ |
| 715 | |
| 716 | hdr = bp->data; |
| 717 | ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) || |
| 718 | hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC)); |
| 719 | ASSERT(be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG); |
| 720 | ASSERT(offset >= (char *)dup - (char *)hdr); |
| 721 | ASSERT(offset + len <= (char *)dup + be16_to_cpu(dup->length) - (char *)hdr); |
| 722 | ASSERT((char *)dup - (char *)hdr == be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup))); |
| 723 | /* |
| 724 | * Look up the entry in the bestfree table. |
| 725 | */ |
| 726 | dfp = xfs_dir2_data_freefind(hdr, dup); |
| 727 | oldlen = be16_to_cpu(dup->length); |
| 728 | ASSERT(dfp || oldlen <= be16_to_cpu(hdr->bestfree[2].length)); |
| 729 | /* |
| 730 | * Check for alignment with front and back of the entry. |
| 731 | */ |
| 732 | matchfront = (char *)dup - (char *)hdr == offset; |
| 733 | matchback = (char *)dup + oldlen - (char *)hdr == offset + len; |
| 734 | ASSERT(*needscanp == 0); |
| 735 | needscan = 0; |
| 736 | /* |
| 737 | * If we matched it exactly we just need to get rid of it from |
| 738 | * the bestfree table. |
| 739 | */ |
| 740 | if (matchfront && matchback) { |
| 741 | if (dfp) { |
| 742 | needscan = (hdr->bestfree[2].offset != 0); |
| 743 | if (!needscan) |
| 744 | xfs_dir2_data_freeremove(hdr, dfp, needlogp); |
| 745 | } |
| 746 | } |
| 747 | /* |
| 748 | * We match the first part of the entry. |
| 749 | * Make a new entry with the remaining freespace. |
| 750 | */ |
| 751 | else if (matchfront) { |
| 752 | newdup = (xfs_dir2_data_unused_t *)((char *)hdr + offset + len); |
| 753 | newdup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG); |
| 754 | newdup->length = cpu_to_be16(oldlen - len); |
| 755 | *xfs_dir2_data_unused_tag_p(newdup) = |
| 756 | cpu_to_be16((char *)newdup - (char *)hdr); |
| 757 | xfs_dir2_data_log_unused(tp, bp, newdup); |
| 758 | /* |
| 759 | * If it was in the table, remove it and add the new one. |
| 760 | */ |
| 761 | if (dfp) { |
| 762 | xfs_dir2_data_freeremove(hdr, dfp, needlogp); |
| 763 | dfp = xfs_dir2_data_freeinsert(hdr, newdup, needlogp); |
| 764 | ASSERT(dfp != NULL); |
| 765 | ASSERT(dfp->length == newdup->length); |
| 766 | ASSERT(be16_to_cpu(dfp->offset) == (char *)newdup - (char *)hdr); |
| 767 | /* |
| 768 | * If we got inserted at the last slot, |
| 769 | * that means we don't know if there was a better |
| 770 | * choice for the last slot, or not. Rescan. |
| 771 | */ |
| 772 | needscan = dfp == &hdr->bestfree[2]; |
| 773 | } |
| 774 | } |
| 775 | /* |
| 776 | * We match the last part of the entry. |
| 777 | * Trim the allocated space off the tail of the entry. |
| 778 | */ |
| 779 | else if (matchback) { |
| 780 | newdup = dup; |
| 781 | newdup->length = cpu_to_be16(((char *)hdr + offset) - (char *)newdup); |
| 782 | *xfs_dir2_data_unused_tag_p(newdup) = |
| 783 | cpu_to_be16((char *)newdup - (char *)hdr); |
| 784 | xfs_dir2_data_log_unused(tp, bp, newdup); |
| 785 | /* |
| 786 | * If it was in the table, remove it and add the new one. |
| 787 | */ |
| 788 | if (dfp) { |
| 789 | xfs_dir2_data_freeremove(hdr, dfp, needlogp); |
| 790 | dfp = xfs_dir2_data_freeinsert(hdr, newdup, needlogp); |
| 791 | ASSERT(dfp != NULL); |
| 792 | ASSERT(dfp->length == newdup->length); |
| 793 | ASSERT(be16_to_cpu(dfp->offset) == (char *)newdup - (char *)hdr); |
| 794 | /* |
| 795 | * If we got inserted at the last slot, |
| 796 | * that means we don't know if there was a better |
| 797 | * choice for the last slot, or not. Rescan. |
| 798 | */ |
| 799 | needscan = dfp == &hdr->bestfree[2]; |
| 800 | } |
| 801 | } |
| 802 | /* |
| 803 | * Poking out the middle of an entry. |
| 804 | * Make two new entries. |
| 805 | */ |
| 806 | else { |
| 807 | newdup = dup; |
| 808 | newdup->length = cpu_to_be16(((char *)hdr + offset) - (char *)newdup); |
| 809 | *xfs_dir2_data_unused_tag_p(newdup) = |
| 810 | cpu_to_be16((char *)newdup - (char *)hdr); |
| 811 | xfs_dir2_data_log_unused(tp, bp, newdup); |
| 812 | newdup2 = (xfs_dir2_data_unused_t *)((char *)hdr + offset + len); |
| 813 | newdup2->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG); |
| 814 | newdup2->length = cpu_to_be16(oldlen - len - be16_to_cpu(newdup->length)); |
| 815 | *xfs_dir2_data_unused_tag_p(newdup2) = |
| 816 | cpu_to_be16((char *)newdup2 - (char *)hdr); |
| 817 | xfs_dir2_data_log_unused(tp, bp, newdup2); |
| 818 | /* |
| 819 | * If the old entry was in the table, we need to scan |
| 820 | * if the 3rd entry was valid, since these entries |
| 821 | * are smaller than the old one. |
| 822 | * If we don't need to scan that means there were 1 or 2 |
| 823 | * entries in the table, and removing the old and adding |
| 824 | * the 2 new will work. |
| 825 | */ |
| 826 | if (dfp) { |
| 827 | needscan = (hdr->bestfree[2].length != 0); |
| 828 | if (!needscan) { |
| 829 | xfs_dir2_data_freeremove(hdr, dfp, needlogp); |
| 830 | xfs_dir2_data_freeinsert(hdr, newdup, needlogp); |
| 831 | xfs_dir2_data_freeinsert(hdr, newdup2, |
| 832 | needlogp); |
| 833 | } |
| 834 | } |
| 835 | } |
| 836 | *needscanp = needscan; |
| 837 | } |