Commit | Line | Data |
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4a8af273 DC |
1 | /* |
2 | * Copyright (c) 2000-2005 Silicon Graphics, Inc. | |
3 | * Copyright (c) 2013 Red Hat, Inc. | |
4 | * All Rights Reserved. | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or | |
7 | * modify it under the terms of the GNU General Public License as | |
8 | * published by the Free Software Foundation. | |
9 | * | |
10 | * This program is distributed in the hope that it would be useful, | |
11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
13 | * GNU General Public License for more details. | |
14 | * | |
15 | * You should have received a copy of the GNU General Public License | |
16 | * along with this program; if not, write the Free Software Foundation, | |
17 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA | |
18 | */ | |
19 | #include "xfs.h" | |
20 | #include "xfs_fs.h" | |
a4fbe6ab | 21 | #include "xfs_format.h" |
239880ef DC |
22 | #include "xfs_log_format.h" |
23 | #include "xfs_trans_resv.h" | |
4a8af273 | 24 | #include "xfs_bit.h" |
4a8af273 | 25 | #include "xfs_mount.h" |
57062787 | 26 | #include "xfs_da_format.h" |
4a8af273 | 27 | #include "xfs_da_btree.h" |
4a8af273 | 28 | #include "xfs_inode.h" |
2b9ab5ab | 29 | #include "xfs_dir2.h" |
4a8af273 DC |
30 | #include "xfs_dir2_priv.h" |
31 | #include "xfs_error.h" | |
32 | #include "xfs_trace.h" | |
33 | #include "xfs_bmap.h" | |
239880ef | 34 | #include "xfs_trans.h" |
4a8af273 | 35 | |
0cb97766 DC |
36 | /* |
37 | * Directory file type support functions | |
38 | */ | |
39 | static unsigned char xfs_dir3_filetype_table[] = { | |
40 | DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, | |
41 | DT_FIFO, DT_SOCK, DT_LNK, DT_WHT, | |
42 | }; | |
43 | ||
1b767ee3 | 44 | static unsigned char |
0cb97766 DC |
45 | xfs_dir3_get_dtype( |
46 | struct xfs_mount *mp, | |
47 | __uint8_t filetype) | |
48 | { | |
49 | if (!xfs_sb_version_hasftype(&mp->m_sb)) | |
50 | return DT_UNKNOWN; | |
51 | ||
52 | if (filetype >= XFS_DIR3_FT_MAX) | |
53 | return DT_UNKNOWN; | |
54 | ||
55 | return xfs_dir3_filetype_table[filetype]; | |
56 | } | |
0cb97766 | 57 | |
4a8af273 DC |
58 | STATIC int |
59 | xfs_dir2_sf_getdents( | |
53f82db0 | 60 | struct xfs_da_args *args, |
4a8af273 DC |
61 | struct dir_context *ctx) |
62 | { | |
63 | int i; /* shortform entry number */ | |
53f82db0 | 64 | struct xfs_inode *dp = args->dp; /* incore directory inode */ |
4a8af273 DC |
65 | xfs_dir2_dataptr_t off; /* current entry's offset */ |
66 | xfs_dir2_sf_entry_t *sfep; /* shortform directory entry */ | |
67 | xfs_dir2_sf_hdr_t *sfp; /* shortform structure */ | |
68 | xfs_dir2_dataptr_t dot_offset; | |
69 | xfs_dir2_dataptr_t dotdot_offset; | |
70 | xfs_ino_t ino; | |
53f82db0 | 71 | struct xfs_da_geometry *geo = args->geo; |
4a8af273 DC |
72 | |
73 | ASSERT(dp->i_df.if_flags & XFS_IFINLINE); | |
74 | /* | |
75 | * Give up if the directory is way too short. | |
76 | */ | |
77 | if (dp->i_d.di_size < offsetof(xfs_dir2_sf_hdr_t, parent)) { | |
53f82db0 | 78 | ASSERT(XFS_FORCED_SHUTDOWN(dp->i_mount)); |
2451337d | 79 | return -EIO; |
4a8af273 DC |
80 | } |
81 | ||
82 | ASSERT(dp->i_df.if_bytes == dp->i_d.di_size); | |
83 | ASSERT(dp->i_df.if_u1.if_data != NULL); | |
84 | ||
85 | sfp = (xfs_dir2_sf_hdr_t *)dp->i_df.if_u1.if_data; | |
86 | ||
87 | ASSERT(dp->i_d.di_size >= xfs_dir2_sf_hdr_size(sfp->i8count)); | |
88 | ||
89 | /* | |
90 | * If the block number in the offset is out of range, we're done. | |
91 | */ | |
7dda6e86 | 92 | if (xfs_dir2_dataptr_to_db(geo, ctx->pos) > geo->datablk) |
4a8af273 DC |
93 | return 0; |
94 | ||
95 | /* | |
96 | * Precalculate offsets for . and .. as we will always need them. | |
97 | * | |
98 | * XXX(hch): the second argument is sometimes 0 and sometimes | |
7dda6e86 | 99 | * geo->datablk |
4a8af273 | 100 | */ |
7dda6e86 | 101 | dot_offset = xfs_dir2_db_off_to_dataptr(geo, geo->datablk, |
1c9a5b2e | 102 | dp->d_ops->data_dot_offset); |
7dda6e86 | 103 | dotdot_offset = xfs_dir2_db_off_to_dataptr(geo, geo->datablk, |
1c9a5b2e | 104 | dp->d_ops->data_dotdot_offset); |
4a8af273 DC |
105 | |
106 | /* | |
107 | * Put . entry unless we're starting past it. | |
108 | */ | |
109 | if (ctx->pos <= dot_offset) { | |
110 | ctx->pos = dot_offset & 0x7fffffff; | |
111 | if (!dir_emit(ctx, ".", 1, dp->i_ino, DT_DIR)) | |
112 | return 0; | |
113 | } | |
114 | ||
115 | /* | |
116 | * Put .. entry unless we're starting past it. | |
117 | */ | |
118 | if (ctx->pos <= dotdot_offset) { | |
4740175e | 119 | ino = dp->d_ops->sf_get_parent_ino(sfp); |
4a8af273 DC |
120 | ctx->pos = dotdot_offset & 0x7fffffff; |
121 | if (!dir_emit(ctx, "..", 2, ino, DT_DIR)) | |
122 | return 0; | |
123 | } | |
124 | ||
125 | /* | |
126 | * Loop while there are more entries and put'ing works. | |
127 | */ | |
128 | sfep = xfs_dir2_sf_firstentry(sfp); | |
129 | for (i = 0; i < sfp->count; i++) { | |
0cb97766 DC |
130 | __uint8_t filetype; |
131 | ||
7dda6e86 | 132 | off = xfs_dir2_db_off_to_dataptr(geo, geo->datablk, |
4a8af273 DC |
133 | xfs_dir2_sf_get_offset(sfep)); |
134 | ||
135 | if (ctx->pos > off) { | |
32c5483a | 136 | sfep = dp->d_ops->sf_nextentry(sfp, sfep); |
4a8af273 DC |
137 | continue; |
138 | } | |
139 | ||
4740175e DC |
140 | ino = dp->d_ops->sf_get_ino(sfp, sfep); |
141 | filetype = dp->d_ops->sf_get_ftype(sfep); | |
4a8af273 | 142 | ctx->pos = off & 0x7fffffff; |
0cb97766 | 143 | if (!dir_emit(ctx, (char *)sfep->name, sfep->namelen, ino, |
53f82db0 | 144 | xfs_dir3_get_dtype(dp->i_mount, filetype))) |
4a8af273 | 145 | return 0; |
32c5483a | 146 | sfep = dp->d_ops->sf_nextentry(sfp, sfep); |
4a8af273 DC |
147 | } |
148 | ||
7dda6e86 | 149 | ctx->pos = xfs_dir2_db_off_to_dataptr(geo, geo->datablk + 1, 0) & |
53f82db0 | 150 | 0x7fffffff; |
4a8af273 DC |
151 | return 0; |
152 | } | |
153 | ||
154 | /* | |
155 | * Readdir for block directories. | |
156 | */ | |
157 | STATIC int | |
158 | xfs_dir2_block_getdents( | |
53f82db0 | 159 | struct xfs_da_args *args, |
4a8af273 DC |
160 | struct dir_context *ctx) |
161 | { | |
53f82db0 | 162 | struct xfs_inode *dp = args->dp; /* incore directory inode */ |
4a8af273 DC |
163 | xfs_dir2_data_hdr_t *hdr; /* block header */ |
164 | struct xfs_buf *bp; /* buffer for block */ | |
165 | xfs_dir2_block_tail_t *btp; /* block tail */ | |
166 | xfs_dir2_data_entry_t *dep; /* block data entry */ | |
167 | xfs_dir2_data_unused_t *dup; /* block unused entry */ | |
168 | char *endptr; /* end of the data entries */ | |
169 | int error; /* error return value */ | |
4a8af273 DC |
170 | char *ptr; /* current data entry */ |
171 | int wantoff; /* starting block offset */ | |
172 | xfs_off_t cook; | |
53f82db0 | 173 | struct xfs_da_geometry *geo = args->geo; |
dbad7c99 | 174 | int lock_mode; |
4a8af273 | 175 | |
4a8af273 DC |
176 | /* |
177 | * If the block number in the offset is out of range, we're done. | |
178 | */ | |
7dda6e86 | 179 | if (xfs_dir2_dataptr_to_db(geo, ctx->pos) > geo->datablk) |
4a8af273 DC |
180 | return 0; |
181 | ||
dbad7c99 | 182 | lock_mode = xfs_ilock_data_map_shared(dp); |
4a8af273 | 183 | error = xfs_dir3_block_read(NULL, dp, &bp); |
dbad7c99 | 184 | xfs_iunlock(dp, lock_mode); |
4a8af273 DC |
185 | if (error) |
186 | return error; | |
187 | ||
188 | /* | |
189 | * Extract the byte offset we start at from the seek pointer. | |
190 | * We'll skip entries before this. | |
191 | */ | |
30028030 | 192 | wantoff = xfs_dir2_dataptr_to_off(geo, ctx->pos); |
4a8af273 DC |
193 | hdr = bp->b_addr; |
194 | xfs_dir3_data_check(dp, bp); | |
195 | /* | |
196 | * Set up values for the loop. | |
197 | */ | |
8f66193c | 198 | btp = xfs_dir2_block_tail_p(geo, hdr); |
2ca98774 | 199 | ptr = (char *)dp->d_ops->data_entry_p(hdr); |
4a8af273 DC |
200 | endptr = (char *)xfs_dir2_block_leaf_p(btp); |
201 | ||
202 | /* | |
203 | * Loop over the data portion of the block. | |
204 | * Each object is a real entry (dep) or an unused one (dup). | |
205 | */ | |
206 | while (ptr < endptr) { | |
0cb97766 DC |
207 | __uint8_t filetype; |
208 | ||
4a8af273 DC |
209 | dup = (xfs_dir2_data_unused_t *)ptr; |
210 | /* | |
211 | * Unused, skip it. | |
212 | */ | |
213 | if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) { | |
214 | ptr += be16_to_cpu(dup->length); | |
215 | continue; | |
216 | } | |
217 | ||
218 | dep = (xfs_dir2_data_entry_t *)ptr; | |
219 | ||
220 | /* | |
221 | * Bump pointer for the next iteration. | |
222 | */ | |
9d23fc85 | 223 | ptr += dp->d_ops->data_entsize(dep->namelen); |
4a8af273 DC |
224 | /* |
225 | * The entry is before the desired starting point, skip it. | |
226 | */ | |
227 | if ((char *)dep - (char *)hdr < wantoff) | |
228 | continue; | |
229 | ||
7dda6e86 | 230 | cook = xfs_dir2_db_off_to_dataptr(geo, geo->datablk, |
4a8af273 DC |
231 | (char *)dep - (char *)hdr); |
232 | ||
233 | ctx->pos = cook & 0x7fffffff; | |
9d23fc85 | 234 | filetype = dp->d_ops->data_get_ftype(dep); |
4a8af273 DC |
235 | /* |
236 | * If it didn't fit, set the final offset to here & return. | |
237 | */ | |
238 | if (!dir_emit(ctx, (char *)dep->name, dep->namelen, | |
0cb97766 | 239 | be64_to_cpu(dep->inumber), |
53f82db0 | 240 | xfs_dir3_get_dtype(dp->i_mount, filetype))) { |
4a8af273 DC |
241 | xfs_trans_brelse(NULL, bp); |
242 | return 0; | |
243 | } | |
244 | } | |
245 | ||
246 | /* | |
247 | * Reached the end of the block. | |
248 | * Set the offset to a non-existent block 1 and return. | |
249 | */ | |
7dda6e86 | 250 | ctx->pos = xfs_dir2_db_off_to_dataptr(geo, geo->datablk + 1, 0) & |
53f82db0 | 251 | 0x7fffffff; |
4a8af273 DC |
252 | xfs_trans_brelse(NULL, bp); |
253 | return 0; | |
254 | } | |
255 | ||
256 | struct xfs_dir2_leaf_map_info { | |
257 | xfs_extlen_t map_blocks; /* number of fsbs in map */ | |
258 | xfs_dablk_t map_off; /* last mapped file offset */ | |
259 | int map_size; /* total entries in *map */ | |
260 | int map_valid; /* valid entries in *map */ | |
261 | int nmap; /* mappings to ask xfs_bmapi */ | |
262 | xfs_dir2_db_t curdb; /* db for current block */ | |
263 | int ra_current; /* number of read-ahead blks */ | |
264 | int ra_index; /* *map index for read-ahead */ | |
265 | int ra_offset; /* map entry offset for ra */ | |
266 | int ra_want; /* readahead count wanted */ | |
267 | struct xfs_bmbt_irec map[]; /* map vector for blocks */ | |
268 | }; | |
269 | ||
270 | STATIC int | |
271 | xfs_dir2_leaf_readbuf( | |
53f82db0 | 272 | struct xfs_da_args *args, |
4a8af273 DC |
273 | size_t bufsize, |
274 | struct xfs_dir2_leaf_map_info *mip, | |
275 | xfs_dir2_off_t *curoff, | |
9f541801 DC |
276 | struct xfs_buf **bpp, |
277 | bool trim_map) | |
4a8af273 | 278 | { |
53f82db0 | 279 | struct xfs_inode *dp = args->dp; |
9f541801 | 280 | struct xfs_buf *bp = NULL; |
4a8af273 DC |
281 | struct xfs_bmbt_irec *map = mip->map; |
282 | struct blk_plug plug; | |
283 | int error = 0; | |
284 | int length; | |
285 | int i; | |
286 | int j; | |
53f82db0 | 287 | struct xfs_da_geometry *geo = args->geo; |
4a8af273 DC |
288 | |
289 | /* | |
9f541801 DC |
290 | * If the caller just finished processing a buffer, it will tell us |
291 | * we need to trim that block out of the mapping now it is done. | |
4a8af273 | 292 | */ |
9f541801 | 293 | if (trim_map) { |
d6cf1305 | 294 | mip->map_blocks -= geo->fsbcount; |
4a8af273 DC |
295 | /* |
296 | * Loop to get rid of the extents for the | |
297 | * directory block. | |
298 | */ | |
d6cf1305 | 299 | for (i = geo->fsbcount; i > 0; ) { |
4a8af273 DC |
300 | j = min_t(int, map->br_blockcount, i); |
301 | map->br_blockcount -= j; | |
302 | map->br_startblock += j; | |
303 | map->br_startoff += j; | |
304 | /* | |
305 | * If mapping is done, pitch it from | |
306 | * the table. | |
307 | */ | |
308 | if (!map->br_blockcount && --mip->map_valid) | |
309 | memmove(&map[0], &map[1], | |
310 | sizeof(map[0]) * mip->map_valid); | |
311 | i -= j; | |
312 | } | |
313 | } | |
314 | ||
315 | /* | |
316 | * Recalculate the readahead blocks wanted. | |
317 | */ | |
53f82db0 | 318 | mip->ra_want = howmany(bufsize + geo->blksize, (1 << geo->fsblog)) - 1; |
4a8af273 DC |
319 | ASSERT(mip->ra_want >= 0); |
320 | ||
321 | /* | |
322 | * If we don't have as many as we want, and we haven't | |
323 | * run out of data blocks, get some more mappings. | |
324 | */ | |
325 | if (1 + mip->ra_want > mip->map_blocks && | |
30028030 | 326 | mip->map_off < xfs_dir2_byte_to_da(geo, XFS_DIR2_LEAF_OFFSET)) { |
4a8af273 DC |
327 | /* |
328 | * Get more bmaps, fill in after the ones | |
329 | * we already have in the table. | |
330 | */ | |
331 | mip->nmap = mip->map_size - mip->map_valid; | |
332 | error = xfs_bmapi_read(dp, mip->map_off, | |
30028030 | 333 | xfs_dir2_byte_to_da(geo, XFS_DIR2_LEAF_OFFSET) - |
4a8af273 DC |
334 | mip->map_off, |
335 | &map[mip->map_valid], &mip->nmap, 0); | |
336 | ||
337 | /* | |
338 | * Don't know if we should ignore this or try to return an | |
339 | * error. The trouble with returning errors is that readdir | |
340 | * will just stop without actually passing the error through. | |
341 | */ | |
342 | if (error) | |
343 | goto out; /* XXX */ | |
344 | ||
345 | /* | |
346 | * If we got all the mappings we asked for, set the final map | |
347 | * offset based on the last bmap value received. Otherwise, | |
348 | * we've reached the end. | |
349 | */ | |
350 | if (mip->nmap == mip->map_size - mip->map_valid) { | |
351 | i = mip->map_valid + mip->nmap - 1; | |
352 | mip->map_off = map[i].br_startoff + map[i].br_blockcount; | |
353 | } else | |
30028030 | 354 | mip->map_off = xfs_dir2_byte_to_da(geo, |
4a8af273 DC |
355 | XFS_DIR2_LEAF_OFFSET); |
356 | ||
357 | /* | |
358 | * Look for holes in the mapping, and eliminate them. Count up | |
359 | * the valid blocks. | |
360 | */ | |
361 | for (i = mip->map_valid; i < mip->map_valid + mip->nmap; ) { | |
362 | if (map[i].br_startblock == HOLESTARTBLOCK) { | |
363 | mip->nmap--; | |
364 | length = mip->map_valid + mip->nmap - i; | |
365 | if (length) | |
366 | memmove(&map[i], &map[i + 1], | |
367 | sizeof(map[i]) * length); | |
368 | } else { | |
369 | mip->map_blocks += map[i].br_blockcount; | |
370 | i++; | |
371 | } | |
372 | } | |
373 | mip->map_valid += mip->nmap; | |
374 | } | |
375 | ||
376 | /* | |
377 | * No valid mappings, so no more data blocks. | |
378 | */ | |
379 | if (!mip->map_valid) { | |
30028030 | 380 | *curoff = xfs_dir2_da_to_byte(geo, mip->map_off); |
4a8af273 DC |
381 | goto out; |
382 | } | |
383 | ||
384 | /* | |
385 | * Read the directory block starting at the first mapping. | |
386 | */ | |
30028030 | 387 | mip->curdb = xfs_dir2_da_to_db(geo, map->br_startoff); |
4a8af273 | 388 | error = xfs_dir3_data_read(NULL, dp, map->br_startoff, |
d6cf1305 | 389 | map->br_blockcount >= geo->fsbcount ? |
53f82db0 DC |
390 | XFS_FSB_TO_DADDR(dp->i_mount, map->br_startblock) : |
391 | -1, &bp); | |
4a8af273 DC |
392 | /* |
393 | * Should just skip over the data block instead of giving up. | |
394 | */ | |
395 | if (error) | |
396 | goto out; /* XXX */ | |
397 | ||
398 | /* | |
399 | * Adjust the current amount of read-ahead: we just read a block that | |
400 | * was previously ra. | |
401 | */ | |
402 | if (mip->ra_current) | |
d6cf1305 | 403 | mip->ra_current -= geo->fsbcount; |
4a8af273 DC |
404 | |
405 | /* | |
406 | * Do we need more readahead? | |
407 | */ | |
408 | blk_start_plug(&plug); | |
409 | for (mip->ra_index = mip->ra_offset = i = 0; | |
410 | mip->ra_want > mip->ra_current && i < mip->map_blocks; | |
d6cf1305 | 411 | i += geo->fsbcount) { |
4a8af273 DC |
412 | ASSERT(mip->ra_index < mip->map_valid); |
413 | /* | |
414 | * Read-ahead a contiguous directory block. | |
415 | */ | |
416 | if (i > mip->ra_current && | |
d6cf1305 | 417 | map[mip->ra_index].br_blockcount >= geo->fsbcount) { |
9df2dd0b | 418 | xfs_dir3_data_readahead(dp, |
4a8af273 | 419 | map[mip->ra_index].br_startoff + mip->ra_offset, |
53f82db0 | 420 | XFS_FSB_TO_DADDR(dp->i_mount, |
4a8af273 DC |
421 | map[mip->ra_index].br_startblock + |
422 | mip->ra_offset)); | |
423 | mip->ra_current = i; | |
424 | } | |
425 | ||
426 | /* | |
427 | * Read-ahead a non-contiguous directory block. This doesn't | |
428 | * use our mapping, but this is a very rare case. | |
429 | */ | |
430 | else if (i > mip->ra_current) { | |
9df2dd0b | 431 | xfs_dir3_data_readahead(dp, |
4a8af273 DC |
432 | map[mip->ra_index].br_startoff + |
433 | mip->ra_offset, -1); | |
434 | mip->ra_current = i; | |
435 | } | |
436 | ||
437 | /* | |
438 | * Advance offset through the mapping table. | |
439 | */ | |
d6cf1305 | 440 | for (j = 0; j < geo->fsbcount; j += length ) { |
4a8af273 DC |
441 | /* |
442 | * The rest of this extent but not more than a dir | |
443 | * block. | |
444 | */ | |
d6cf1305 | 445 | length = min_t(int, geo->fsbcount, |
4a8af273 DC |
446 | map[mip->ra_index].br_blockcount - |
447 | mip->ra_offset); | |
4a8af273 DC |
448 | mip->ra_offset += length; |
449 | ||
450 | /* | |
451 | * Advance to the next mapping if this one is used up. | |
452 | */ | |
453 | if (mip->ra_offset == map[mip->ra_index].br_blockcount) { | |
454 | mip->ra_offset = 0; | |
455 | mip->ra_index++; | |
456 | } | |
457 | } | |
458 | } | |
459 | blk_finish_plug(&plug); | |
460 | ||
461 | out: | |
462 | *bpp = bp; | |
463 | return error; | |
464 | } | |
465 | ||
466 | /* | |
467 | * Getdents (readdir) for leaf and node directories. | |
468 | * This reads the data blocks only, so is the same for both forms. | |
469 | */ | |
470 | STATIC int | |
471 | xfs_dir2_leaf_getdents( | |
53f82db0 | 472 | struct xfs_da_args *args, |
4a8af273 DC |
473 | struct dir_context *ctx, |
474 | size_t bufsize) | |
475 | { | |
53f82db0 | 476 | struct xfs_inode *dp = args->dp; |
4a8af273 DC |
477 | struct xfs_buf *bp = NULL; /* data block buffer */ |
478 | xfs_dir2_data_hdr_t *hdr; /* data block header */ | |
479 | xfs_dir2_data_entry_t *dep; /* data entry */ | |
480 | xfs_dir2_data_unused_t *dup; /* unused entry */ | |
481 | int error = 0; /* error return value */ | |
482 | int length; /* temporary length value */ | |
4a8af273 DC |
483 | int byteoff; /* offset in current block */ |
484 | xfs_dir2_off_t curoff; /* current overall offset */ | |
485 | xfs_dir2_off_t newoff; /* new curoff after new blk */ | |
486 | char *ptr = NULL; /* pointer to current data */ | |
487 | struct xfs_dir2_leaf_map_info *map_info; | |
53f82db0 | 488 | struct xfs_da_geometry *geo = args->geo; |
4a8af273 DC |
489 | |
490 | /* | |
491 | * If the offset is at or past the largest allowed value, | |
492 | * give up right away. | |
493 | */ | |
494 | if (ctx->pos >= XFS_DIR2_MAX_DATAPTR) | |
495 | return 0; | |
496 | ||
4a8af273 DC |
497 | /* |
498 | * Set up to bmap a number of blocks based on the caller's | |
499 | * buffer size, the directory block size, and the filesystem | |
500 | * block size. | |
501 | */ | |
53f82db0 | 502 | length = howmany(bufsize + geo->blksize, (1 << geo->fsblog)); |
4a8af273 DC |
503 | map_info = kmem_zalloc(offsetof(struct xfs_dir2_leaf_map_info, map) + |
504 | (length * sizeof(struct xfs_bmbt_irec)), | |
505 | KM_SLEEP | KM_NOFS); | |
506 | map_info->map_size = length; | |
507 | ||
508 | /* | |
509 | * Inside the loop we keep the main offset value as a byte offset | |
510 | * in the directory file. | |
511 | */ | |
25994053 | 512 | curoff = xfs_dir2_dataptr_to_byte(ctx->pos); |
4a8af273 DC |
513 | |
514 | /* | |
515 | * Force this conversion through db so we truncate the offset | |
516 | * down to get the start of the data block. | |
517 | */ | |
30028030 DC |
518 | map_info->map_off = xfs_dir2_db_to_da(geo, |
519 | xfs_dir2_byte_to_db(geo, curoff)); | |
4a8af273 DC |
520 | |
521 | /* | |
522 | * Loop over directory entries until we reach the end offset. | |
523 | * Get more blocks and readahead as necessary. | |
524 | */ | |
525 | while (curoff < XFS_DIR2_LEAF_OFFSET) { | |
0cb97766 DC |
526 | __uint8_t filetype; |
527 | ||
4a8af273 DC |
528 | /* |
529 | * If we have no buffer, or we're off the end of the | |
530 | * current buffer, need to get another one. | |
531 | */ | |
8f66193c | 532 | if (!bp || ptr >= (char *)bp->b_addr + geo->blksize) { |
dbad7c99 | 533 | int lock_mode; |
9f541801 DC |
534 | bool trim_map = false; |
535 | ||
536 | if (bp) { | |
537 | xfs_trans_brelse(NULL, bp); | |
538 | bp = NULL; | |
539 | trim_map = true; | |
540 | } | |
4a8af273 | 541 | |
dbad7c99 | 542 | lock_mode = xfs_ilock_data_map_shared(dp); |
53f82db0 | 543 | error = xfs_dir2_leaf_readbuf(args, bufsize, map_info, |
9f541801 | 544 | &curoff, &bp, trim_map); |
dbad7c99 | 545 | xfs_iunlock(dp, lock_mode); |
4a8af273 DC |
546 | if (error || !map_info->map_valid) |
547 | break; | |
548 | ||
549 | /* | |
550 | * Having done a read, we need to set a new offset. | |
551 | */ | |
53f82db0 | 552 | newoff = xfs_dir2_db_off_to_byte(geo, |
9b3b5522 | 553 | map_info->curdb, 0); |
4a8af273 DC |
554 | /* |
555 | * Start of the current block. | |
556 | */ | |
557 | if (curoff < newoff) | |
558 | curoff = newoff; | |
559 | /* | |
560 | * Make sure we're in the right block. | |
561 | */ | |
562 | else if (curoff > newoff) | |
30028030 | 563 | ASSERT(xfs_dir2_byte_to_db(geo, curoff) == |
4a8af273 DC |
564 | map_info->curdb); |
565 | hdr = bp->b_addr; | |
566 | xfs_dir3_data_check(dp, bp); | |
567 | /* | |
568 | * Find our position in the block. | |
569 | */ | |
2ca98774 | 570 | ptr = (char *)dp->d_ops->data_entry_p(hdr); |
53f82db0 | 571 | byteoff = xfs_dir2_byte_to_off(geo, curoff); |
4a8af273 DC |
572 | /* |
573 | * Skip past the header. | |
574 | */ | |
575 | if (byteoff == 0) | |
1c9a5b2e | 576 | curoff += dp->d_ops->data_entry_offset; |
4a8af273 DC |
577 | /* |
578 | * Skip past entries until we reach our offset. | |
579 | */ | |
580 | else { | |
581 | while ((char *)ptr - (char *)hdr < byteoff) { | |
582 | dup = (xfs_dir2_data_unused_t *)ptr; | |
583 | ||
584 | if (be16_to_cpu(dup->freetag) | |
585 | == XFS_DIR2_DATA_FREE_TAG) { | |
586 | ||
587 | length = be16_to_cpu(dup->length); | |
588 | ptr += length; | |
589 | continue; | |
590 | } | |
591 | dep = (xfs_dir2_data_entry_t *)ptr; | |
592 | length = | |
9d23fc85 | 593 | dp->d_ops->data_entsize(dep->namelen); |
4a8af273 DC |
594 | ptr += length; |
595 | } | |
596 | /* | |
597 | * Now set our real offset. | |
598 | */ | |
599 | curoff = | |
30028030 DC |
600 | xfs_dir2_db_off_to_byte(geo, |
601 | xfs_dir2_byte_to_db(geo, curoff), | |
4a8af273 | 602 | (char *)ptr - (char *)hdr); |
8f66193c | 603 | if (ptr >= (char *)hdr + geo->blksize) { |
4a8af273 DC |
604 | continue; |
605 | } | |
606 | } | |
607 | } | |
608 | /* | |
609 | * We have a pointer to an entry. | |
610 | * Is it a live one? | |
611 | */ | |
612 | dup = (xfs_dir2_data_unused_t *)ptr; | |
613 | /* | |
614 | * No, it's unused, skip over it. | |
615 | */ | |
616 | if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) { | |
617 | length = be16_to_cpu(dup->length); | |
618 | ptr += length; | |
619 | curoff += length; | |
620 | continue; | |
621 | } | |
622 | ||
623 | dep = (xfs_dir2_data_entry_t *)ptr; | |
9d23fc85 DC |
624 | length = dp->d_ops->data_entsize(dep->namelen); |
625 | filetype = dp->d_ops->data_get_ftype(dep); | |
4a8af273 | 626 | |
25994053 | 627 | ctx->pos = xfs_dir2_byte_to_dataptr(curoff) & 0x7fffffff; |
4a8af273 | 628 | if (!dir_emit(ctx, (char *)dep->name, dep->namelen, |
0cb97766 | 629 | be64_to_cpu(dep->inumber), |
53f82db0 | 630 | xfs_dir3_get_dtype(dp->i_mount, filetype))) |
4a8af273 DC |
631 | break; |
632 | ||
633 | /* | |
634 | * Advance to next entry in the block. | |
635 | */ | |
636 | ptr += length; | |
637 | curoff += length; | |
638 | /* bufsize may have just been a guess; don't go negative */ | |
639 | bufsize = bufsize > length ? bufsize - length : 0; | |
640 | } | |
641 | ||
642 | /* | |
643 | * All done. Set output offset value to current offset. | |
644 | */ | |
25994053 | 645 | if (curoff > xfs_dir2_dataptr_to_byte(XFS_DIR2_MAX_DATAPTR)) |
4a8af273 DC |
646 | ctx->pos = XFS_DIR2_MAX_DATAPTR & 0x7fffffff; |
647 | else | |
25994053 | 648 | ctx->pos = xfs_dir2_byte_to_dataptr(curoff) & 0x7fffffff; |
4a8af273 DC |
649 | kmem_free(map_info); |
650 | if (bp) | |
651 | xfs_trans_brelse(NULL, bp); | |
652 | return error; | |
653 | } | |
654 | ||
655 | /* | |
656 | * Read a directory. | |
657 | */ | |
658 | int | |
659 | xfs_readdir( | |
53f82db0 DC |
660 | struct xfs_inode *dp, |
661 | struct dir_context *ctx, | |
662 | size_t bufsize) | |
4a8af273 | 663 | { |
35f46c5f | 664 | struct xfs_da_args args = { NULL }; |
53f82db0 DC |
665 | int rval; |
666 | int v; | |
4a8af273 DC |
667 | |
668 | trace_xfs_readdir(dp); | |
669 | ||
670 | if (XFS_FORCED_SHUTDOWN(dp->i_mount)) | |
2451337d | 671 | return -EIO; |
4a8af273 | 672 | |
c19b3b05 | 673 | ASSERT(S_ISDIR(VFS_I(dp)->i_mode)); |
ff6d6af2 | 674 | XFS_STATS_INC(dp->i_mount, xs_dir_getdents); |
4a8af273 | 675 | |
53f82db0 DC |
676 | args.dp = dp; |
677 | args.geo = dp->i_mount->m_dir_geo; | |
678 | ||
dbad7c99 | 679 | xfs_ilock(dp, XFS_IOLOCK_SHARED); |
4a8af273 | 680 | if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL) |
53f82db0 DC |
681 | rval = xfs_dir2_sf_getdents(&args, ctx); |
682 | else if ((rval = xfs_dir2_isblock(&args, &v))) | |
4a8af273 DC |
683 | ; |
684 | else if (v) | |
53f82db0 | 685 | rval = xfs_dir2_block_getdents(&args, ctx); |
4a8af273 | 686 | else |
53f82db0 | 687 | rval = xfs_dir2_leaf_getdents(&args, ctx, bufsize); |
dbad7c99 | 688 | xfs_iunlock(dp, XFS_IOLOCK_SHARED); |
40194ecc | 689 | |
4a8af273 DC |
690 | return rval; |
691 | } |