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_sb.h" |
4a8af273 | 26 | #include "xfs_mount.h" |
57062787 | 27 | #include "xfs_da_format.h" |
4a8af273 | 28 | #include "xfs_da_btree.h" |
4a8af273 | 29 | #include "xfs_inode.h" |
2b9ab5ab | 30 | #include "xfs_dir2.h" |
4a8af273 DC |
31 | #include "xfs_dir2_priv.h" |
32 | #include "xfs_error.h" | |
33 | #include "xfs_trace.h" | |
34 | #include "xfs_bmap.h" | |
239880ef | 35 | #include "xfs_trans.h" |
4a8af273 | 36 | |
0cb97766 DC |
37 | /* |
38 | * Directory file type support functions | |
39 | */ | |
40 | static unsigned char xfs_dir3_filetype_table[] = { | |
41 | DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, | |
42 | DT_FIFO, DT_SOCK, DT_LNK, DT_WHT, | |
43 | }; | |
44 | ||
45 | unsigned char | |
46 | xfs_dir3_get_dtype( | |
47 | struct xfs_mount *mp, | |
48 | __uint8_t filetype) | |
49 | { | |
50 | if (!xfs_sb_version_hasftype(&mp->m_sb)) | |
51 | return DT_UNKNOWN; | |
52 | ||
53 | if (filetype >= XFS_DIR3_FT_MAX) | |
54 | return DT_UNKNOWN; | |
55 | ||
56 | return xfs_dir3_filetype_table[filetype]; | |
57 | } | |
58 | /* | |
59 | * @mode, if set, indicates that the type field needs to be set up. | |
60 | * This uses the transformation from file mode to DT_* as defined in linux/fs.h | |
61 | * for file type specification. This will be propagated into the directory | |
62 | * structure if appropriate for the given operation and filesystem config. | |
63 | */ | |
64 | const unsigned char xfs_mode_to_ftype[S_IFMT >> S_SHIFT] = { | |
65 | [0] = XFS_DIR3_FT_UNKNOWN, | |
66 | [S_IFREG >> S_SHIFT] = XFS_DIR3_FT_REG_FILE, | |
67 | [S_IFDIR >> S_SHIFT] = XFS_DIR3_FT_DIR, | |
68 | [S_IFCHR >> S_SHIFT] = XFS_DIR3_FT_CHRDEV, | |
69 | [S_IFBLK >> S_SHIFT] = XFS_DIR3_FT_BLKDEV, | |
70 | [S_IFIFO >> S_SHIFT] = XFS_DIR3_FT_FIFO, | |
71 | [S_IFSOCK >> S_SHIFT] = XFS_DIR3_FT_SOCK, | |
72 | [S_IFLNK >> S_SHIFT] = XFS_DIR3_FT_SYMLINK, | |
73 | }; | |
74 | ||
4a8af273 DC |
75 | STATIC int |
76 | xfs_dir2_sf_getdents( | |
53f82db0 | 77 | struct xfs_da_args *args, |
4a8af273 DC |
78 | struct dir_context *ctx) |
79 | { | |
80 | int i; /* shortform entry number */ | |
53f82db0 | 81 | struct xfs_inode *dp = args->dp; /* incore directory inode */ |
4a8af273 DC |
82 | xfs_dir2_dataptr_t off; /* current entry's offset */ |
83 | xfs_dir2_sf_entry_t *sfep; /* shortform directory entry */ | |
84 | xfs_dir2_sf_hdr_t *sfp; /* shortform structure */ | |
85 | xfs_dir2_dataptr_t dot_offset; | |
86 | xfs_dir2_dataptr_t dotdot_offset; | |
87 | xfs_ino_t ino; | |
53f82db0 | 88 | struct xfs_da_geometry *geo = args->geo; |
4a8af273 DC |
89 | |
90 | ASSERT(dp->i_df.if_flags & XFS_IFINLINE); | |
91 | /* | |
92 | * Give up if the directory is way too short. | |
93 | */ | |
94 | if (dp->i_d.di_size < offsetof(xfs_dir2_sf_hdr_t, parent)) { | |
53f82db0 | 95 | ASSERT(XFS_FORCED_SHUTDOWN(dp->i_mount)); |
2451337d | 96 | return -EIO; |
4a8af273 DC |
97 | } |
98 | ||
99 | ASSERT(dp->i_df.if_bytes == dp->i_d.di_size); | |
100 | ASSERT(dp->i_df.if_u1.if_data != NULL); | |
101 | ||
102 | sfp = (xfs_dir2_sf_hdr_t *)dp->i_df.if_u1.if_data; | |
103 | ||
104 | ASSERT(dp->i_d.di_size >= xfs_dir2_sf_hdr_size(sfp->i8count)); | |
105 | ||
106 | /* | |
107 | * If the block number in the offset is out of range, we're done. | |
108 | */ | |
7dda6e86 | 109 | if (xfs_dir2_dataptr_to_db(geo, ctx->pos) > geo->datablk) |
4a8af273 DC |
110 | return 0; |
111 | ||
112 | /* | |
113 | * Precalculate offsets for . and .. as we will always need them. | |
114 | * | |
115 | * XXX(hch): the second argument is sometimes 0 and sometimes | |
7dda6e86 | 116 | * geo->datablk |
4a8af273 | 117 | */ |
7dda6e86 | 118 | dot_offset = xfs_dir2_db_off_to_dataptr(geo, geo->datablk, |
1c9a5b2e | 119 | dp->d_ops->data_dot_offset); |
7dda6e86 | 120 | dotdot_offset = xfs_dir2_db_off_to_dataptr(geo, geo->datablk, |
1c9a5b2e | 121 | dp->d_ops->data_dotdot_offset); |
4a8af273 DC |
122 | |
123 | /* | |
124 | * Put . entry unless we're starting past it. | |
125 | */ | |
126 | if (ctx->pos <= dot_offset) { | |
127 | ctx->pos = dot_offset & 0x7fffffff; | |
128 | if (!dir_emit(ctx, ".", 1, dp->i_ino, DT_DIR)) | |
129 | return 0; | |
130 | } | |
131 | ||
132 | /* | |
133 | * Put .. entry unless we're starting past it. | |
134 | */ | |
135 | if (ctx->pos <= dotdot_offset) { | |
4740175e | 136 | ino = dp->d_ops->sf_get_parent_ino(sfp); |
4a8af273 DC |
137 | ctx->pos = dotdot_offset & 0x7fffffff; |
138 | if (!dir_emit(ctx, "..", 2, ino, DT_DIR)) | |
139 | return 0; | |
140 | } | |
141 | ||
142 | /* | |
143 | * Loop while there are more entries and put'ing works. | |
144 | */ | |
145 | sfep = xfs_dir2_sf_firstentry(sfp); | |
146 | for (i = 0; i < sfp->count; i++) { | |
0cb97766 DC |
147 | __uint8_t filetype; |
148 | ||
7dda6e86 | 149 | off = xfs_dir2_db_off_to_dataptr(geo, geo->datablk, |
4a8af273 DC |
150 | xfs_dir2_sf_get_offset(sfep)); |
151 | ||
152 | if (ctx->pos > off) { | |
32c5483a | 153 | sfep = dp->d_ops->sf_nextentry(sfp, sfep); |
4a8af273 DC |
154 | continue; |
155 | } | |
156 | ||
4740175e DC |
157 | ino = dp->d_ops->sf_get_ino(sfp, sfep); |
158 | filetype = dp->d_ops->sf_get_ftype(sfep); | |
4a8af273 | 159 | ctx->pos = off & 0x7fffffff; |
0cb97766 | 160 | if (!dir_emit(ctx, (char *)sfep->name, sfep->namelen, ino, |
53f82db0 | 161 | xfs_dir3_get_dtype(dp->i_mount, filetype))) |
4a8af273 | 162 | return 0; |
32c5483a | 163 | sfep = dp->d_ops->sf_nextentry(sfp, sfep); |
4a8af273 DC |
164 | } |
165 | ||
7dda6e86 | 166 | ctx->pos = xfs_dir2_db_off_to_dataptr(geo, geo->datablk + 1, 0) & |
53f82db0 | 167 | 0x7fffffff; |
4a8af273 DC |
168 | return 0; |
169 | } | |
170 | ||
171 | /* | |
172 | * Readdir for block directories. | |
173 | */ | |
174 | STATIC int | |
175 | xfs_dir2_block_getdents( | |
53f82db0 | 176 | struct xfs_da_args *args, |
4a8af273 DC |
177 | struct dir_context *ctx) |
178 | { | |
53f82db0 | 179 | struct xfs_inode *dp = args->dp; /* incore directory inode */ |
4a8af273 DC |
180 | xfs_dir2_data_hdr_t *hdr; /* block header */ |
181 | struct xfs_buf *bp; /* buffer for block */ | |
182 | xfs_dir2_block_tail_t *btp; /* block tail */ | |
183 | xfs_dir2_data_entry_t *dep; /* block data entry */ | |
184 | xfs_dir2_data_unused_t *dup; /* block unused entry */ | |
185 | char *endptr; /* end of the data entries */ | |
186 | int error; /* error return value */ | |
4a8af273 DC |
187 | char *ptr; /* current data entry */ |
188 | int wantoff; /* starting block offset */ | |
189 | xfs_off_t cook; | |
53f82db0 | 190 | struct xfs_da_geometry *geo = args->geo; |
4a8af273 | 191 | |
4a8af273 DC |
192 | /* |
193 | * If the block number in the offset is out of range, we're done. | |
194 | */ | |
7dda6e86 | 195 | if (xfs_dir2_dataptr_to_db(geo, ctx->pos) > geo->datablk) |
4a8af273 DC |
196 | return 0; |
197 | ||
198 | error = xfs_dir3_block_read(NULL, dp, &bp); | |
199 | if (error) | |
200 | return error; | |
201 | ||
202 | /* | |
203 | * Extract the byte offset we start at from the seek pointer. | |
204 | * We'll skip entries before this. | |
205 | */ | |
30028030 | 206 | wantoff = xfs_dir2_dataptr_to_off(geo, ctx->pos); |
4a8af273 DC |
207 | hdr = bp->b_addr; |
208 | xfs_dir3_data_check(dp, bp); | |
209 | /* | |
210 | * Set up values for the loop. | |
211 | */ | |
8f66193c | 212 | btp = xfs_dir2_block_tail_p(geo, hdr); |
2ca98774 | 213 | ptr = (char *)dp->d_ops->data_entry_p(hdr); |
4a8af273 DC |
214 | endptr = (char *)xfs_dir2_block_leaf_p(btp); |
215 | ||
216 | /* | |
217 | * Loop over the data portion of the block. | |
218 | * Each object is a real entry (dep) or an unused one (dup). | |
219 | */ | |
220 | while (ptr < endptr) { | |
0cb97766 DC |
221 | __uint8_t filetype; |
222 | ||
4a8af273 DC |
223 | dup = (xfs_dir2_data_unused_t *)ptr; |
224 | /* | |
225 | * Unused, skip it. | |
226 | */ | |
227 | if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) { | |
228 | ptr += be16_to_cpu(dup->length); | |
229 | continue; | |
230 | } | |
231 | ||
232 | dep = (xfs_dir2_data_entry_t *)ptr; | |
233 | ||
234 | /* | |
235 | * Bump pointer for the next iteration. | |
236 | */ | |
9d23fc85 | 237 | ptr += dp->d_ops->data_entsize(dep->namelen); |
4a8af273 DC |
238 | /* |
239 | * The entry is before the desired starting point, skip it. | |
240 | */ | |
241 | if ((char *)dep - (char *)hdr < wantoff) | |
242 | continue; | |
243 | ||
7dda6e86 | 244 | cook = xfs_dir2_db_off_to_dataptr(geo, geo->datablk, |
4a8af273 DC |
245 | (char *)dep - (char *)hdr); |
246 | ||
247 | ctx->pos = cook & 0x7fffffff; | |
9d23fc85 | 248 | filetype = dp->d_ops->data_get_ftype(dep); |
4a8af273 DC |
249 | /* |
250 | * If it didn't fit, set the final offset to here & return. | |
251 | */ | |
252 | if (!dir_emit(ctx, (char *)dep->name, dep->namelen, | |
0cb97766 | 253 | be64_to_cpu(dep->inumber), |
53f82db0 | 254 | xfs_dir3_get_dtype(dp->i_mount, filetype))) { |
4a8af273 DC |
255 | xfs_trans_brelse(NULL, bp); |
256 | return 0; | |
257 | } | |
258 | } | |
259 | ||
260 | /* | |
261 | * Reached the end of the block. | |
262 | * Set the offset to a non-existent block 1 and return. | |
263 | */ | |
7dda6e86 | 264 | ctx->pos = xfs_dir2_db_off_to_dataptr(geo, geo->datablk + 1, 0) & |
53f82db0 | 265 | 0x7fffffff; |
4a8af273 DC |
266 | xfs_trans_brelse(NULL, bp); |
267 | return 0; | |
268 | } | |
269 | ||
270 | struct xfs_dir2_leaf_map_info { | |
271 | xfs_extlen_t map_blocks; /* number of fsbs in map */ | |
272 | xfs_dablk_t map_off; /* last mapped file offset */ | |
273 | int map_size; /* total entries in *map */ | |
274 | int map_valid; /* valid entries in *map */ | |
275 | int nmap; /* mappings to ask xfs_bmapi */ | |
276 | xfs_dir2_db_t curdb; /* db for current block */ | |
277 | int ra_current; /* number of read-ahead blks */ | |
278 | int ra_index; /* *map index for read-ahead */ | |
279 | int ra_offset; /* map entry offset for ra */ | |
280 | int ra_want; /* readahead count wanted */ | |
281 | struct xfs_bmbt_irec map[]; /* map vector for blocks */ | |
282 | }; | |
283 | ||
284 | STATIC int | |
285 | xfs_dir2_leaf_readbuf( | |
53f82db0 | 286 | struct xfs_da_args *args, |
4a8af273 DC |
287 | size_t bufsize, |
288 | struct xfs_dir2_leaf_map_info *mip, | |
289 | xfs_dir2_off_t *curoff, | |
290 | struct xfs_buf **bpp) | |
291 | { | |
53f82db0 | 292 | struct xfs_inode *dp = args->dp; |
4a8af273 DC |
293 | struct xfs_buf *bp = *bpp; |
294 | struct xfs_bmbt_irec *map = mip->map; | |
295 | struct blk_plug plug; | |
296 | int error = 0; | |
297 | int length; | |
298 | int i; | |
299 | int j; | |
53f82db0 | 300 | struct xfs_da_geometry *geo = args->geo; |
4a8af273 DC |
301 | |
302 | /* | |
303 | * If we have a buffer, we need to release it and | |
304 | * take it out of the mapping. | |
305 | */ | |
306 | ||
307 | if (bp) { | |
308 | xfs_trans_brelse(NULL, bp); | |
309 | bp = NULL; | |
d6cf1305 | 310 | mip->map_blocks -= geo->fsbcount; |
4a8af273 DC |
311 | /* |
312 | * Loop to get rid of the extents for the | |
313 | * directory block. | |
314 | */ | |
d6cf1305 | 315 | for (i = geo->fsbcount; i > 0; ) { |
4a8af273 DC |
316 | j = min_t(int, map->br_blockcount, i); |
317 | map->br_blockcount -= j; | |
318 | map->br_startblock += j; | |
319 | map->br_startoff += j; | |
320 | /* | |
321 | * If mapping is done, pitch it from | |
322 | * the table. | |
323 | */ | |
324 | if (!map->br_blockcount && --mip->map_valid) | |
325 | memmove(&map[0], &map[1], | |
326 | sizeof(map[0]) * mip->map_valid); | |
327 | i -= j; | |
328 | } | |
329 | } | |
330 | ||
331 | /* | |
332 | * Recalculate the readahead blocks wanted. | |
333 | */ | |
53f82db0 | 334 | mip->ra_want = howmany(bufsize + geo->blksize, (1 << geo->fsblog)) - 1; |
4a8af273 DC |
335 | ASSERT(mip->ra_want >= 0); |
336 | ||
337 | /* | |
338 | * If we don't have as many as we want, and we haven't | |
339 | * run out of data blocks, get some more mappings. | |
340 | */ | |
341 | if (1 + mip->ra_want > mip->map_blocks && | |
30028030 | 342 | mip->map_off < xfs_dir2_byte_to_da(geo, XFS_DIR2_LEAF_OFFSET)) { |
4a8af273 DC |
343 | /* |
344 | * Get more bmaps, fill in after the ones | |
345 | * we already have in the table. | |
346 | */ | |
347 | mip->nmap = mip->map_size - mip->map_valid; | |
348 | error = xfs_bmapi_read(dp, mip->map_off, | |
30028030 | 349 | xfs_dir2_byte_to_da(geo, XFS_DIR2_LEAF_OFFSET) - |
4a8af273 DC |
350 | mip->map_off, |
351 | &map[mip->map_valid], &mip->nmap, 0); | |
352 | ||
353 | /* | |
354 | * Don't know if we should ignore this or try to return an | |
355 | * error. The trouble with returning errors is that readdir | |
356 | * will just stop without actually passing the error through. | |
357 | */ | |
358 | if (error) | |
359 | goto out; /* XXX */ | |
360 | ||
361 | /* | |
362 | * If we got all the mappings we asked for, set the final map | |
363 | * offset based on the last bmap value received. Otherwise, | |
364 | * we've reached the end. | |
365 | */ | |
366 | if (mip->nmap == mip->map_size - mip->map_valid) { | |
367 | i = mip->map_valid + mip->nmap - 1; | |
368 | mip->map_off = map[i].br_startoff + map[i].br_blockcount; | |
369 | } else | |
30028030 | 370 | mip->map_off = xfs_dir2_byte_to_da(geo, |
4a8af273 DC |
371 | XFS_DIR2_LEAF_OFFSET); |
372 | ||
373 | /* | |
374 | * Look for holes in the mapping, and eliminate them. Count up | |
375 | * the valid blocks. | |
376 | */ | |
377 | for (i = mip->map_valid; i < mip->map_valid + mip->nmap; ) { | |
378 | if (map[i].br_startblock == HOLESTARTBLOCK) { | |
379 | mip->nmap--; | |
380 | length = mip->map_valid + mip->nmap - i; | |
381 | if (length) | |
382 | memmove(&map[i], &map[i + 1], | |
383 | sizeof(map[i]) * length); | |
384 | } else { | |
385 | mip->map_blocks += map[i].br_blockcount; | |
386 | i++; | |
387 | } | |
388 | } | |
389 | mip->map_valid += mip->nmap; | |
390 | } | |
391 | ||
392 | /* | |
393 | * No valid mappings, so no more data blocks. | |
394 | */ | |
395 | if (!mip->map_valid) { | |
30028030 | 396 | *curoff = xfs_dir2_da_to_byte(geo, mip->map_off); |
4a8af273 DC |
397 | goto out; |
398 | } | |
399 | ||
400 | /* | |
401 | * Read the directory block starting at the first mapping. | |
402 | */ | |
30028030 | 403 | mip->curdb = xfs_dir2_da_to_db(geo, map->br_startoff); |
4a8af273 | 404 | error = xfs_dir3_data_read(NULL, dp, map->br_startoff, |
d6cf1305 | 405 | map->br_blockcount >= geo->fsbcount ? |
53f82db0 DC |
406 | XFS_FSB_TO_DADDR(dp->i_mount, map->br_startblock) : |
407 | -1, &bp); | |
4a8af273 DC |
408 | /* |
409 | * Should just skip over the data block instead of giving up. | |
410 | */ | |
411 | if (error) | |
412 | goto out; /* XXX */ | |
413 | ||
414 | /* | |
415 | * Adjust the current amount of read-ahead: we just read a block that | |
416 | * was previously ra. | |
417 | */ | |
418 | if (mip->ra_current) | |
d6cf1305 | 419 | mip->ra_current -= geo->fsbcount; |
4a8af273 DC |
420 | |
421 | /* | |
422 | * Do we need more readahead? | |
423 | */ | |
424 | blk_start_plug(&plug); | |
425 | for (mip->ra_index = mip->ra_offset = i = 0; | |
426 | mip->ra_want > mip->ra_current && i < mip->map_blocks; | |
d6cf1305 | 427 | i += geo->fsbcount) { |
4a8af273 DC |
428 | ASSERT(mip->ra_index < mip->map_valid); |
429 | /* | |
430 | * Read-ahead a contiguous directory block. | |
431 | */ | |
432 | if (i > mip->ra_current && | |
d6cf1305 | 433 | map[mip->ra_index].br_blockcount >= geo->fsbcount) { |
9df2dd0b | 434 | xfs_dir3_data_readahead(dp, |
4a8af273 | 435 | map[mip->ra_index].br_startoff + mip->ra_offset, |
53f82db0 | 436 | XFS_FSB_TO_DADDR(dp->i_mount, |
4a8af273 DC |
437 | map[mip->ra_index].br_startblock + |
438 | mip->ra_offset)); | |
439 | mip->ra_current = i; | |
440 | } | |
441 | ||
442 | /* | |
443 | * Read-ahead a non-contiguous directory block. This doesn't | |
444 | * use our mapping, but this is a very rare case. | |
445 | */ | |
446 | else if (i > mip->ra_current) { | |
9df2dd0b | 447 | xfs_dir3_data_readahead(dp, |
4a8af273 DC |
448 | map[mip->ra_index].br_startoff + |
449 | mip->ra_offset, -1); | |
450 | mip->ra_current = i; | |
451 | } | |
452 | ||
453 | /* | |
454 | * Advance offset through the mapping table. | |
455 | */ | |
d6cf1305 | 456 | for (j = 0; j < geo->fsbcount; j += length ) { |
4a8af273 DC |
457 | /* |
458 | * The rest of this extent but not more than a dir | |
459 | * block. | |
460 | */ | |
d6cf1305 | 461 | length = min_t(int, geo->fsbcount, |
4a8af273 DC |
462 | map[mip->ra_index].br_blockcount - |
463 | mip->ra_offset); | |
4a8af273 DC |
464 | mip->ra_offset += length; |
465 | ||
466 | /* | |
467 | * Advance to the next mapping if this one is used up. | |
468 | */ | |
469 | if (mip->ra_offset == map[mip->ra_index].br_blockcount) { | |
470 | mip->ra_offset = 0; | |
471 | mip->ra_index++; | |
472 | } | |
473 | } | |
474 | } | |
475 | blk_finish_plug(&plug); | |
476 | ||
477 | out: | |
478 | *bpp = bp; | |
479 | return error; | |
480 | } | |
481 | ||
482 | /* | |
483 | * Getdents (readdir) for leaf and node directories. | |
484 | * This reads the data blocks only, so is the same for both forms. | |
485 | */ | |
486 | STATIC int | |
487 | xfs_dir2_leaf_getdents( | |
53f82db0 | 488 | struct xfs_da_args *args, |
4a8af273 DC |
489 | struct dir_context *ctx, |
490 | size_t bufsize) | |
491 | { | |
53f82db0 | 492 | struct xfs_inode *dp = args->dp; |
4a8af273 DC |
493 | struct xfs_buf *bp = NULL; /* data block buffer */ |
494 | xfs_dir2_data_hdr_t *hdr; /* data block header */ | |
495 | xfs_dir2_data_entry_t *dep; /* data entry */ | |
496 | xfs_dir2_data_unused_t *dup; /* unused entry */ | |
497 | int error = 0; /* error return value */ | |
498 | int length; /* temporary length value */ | |
4a8af273 DC |
499 | int byteoff; /* offset in current block */ |
500 | xfs_dir2_off_t curoff; /* current overall offset */ | |
501 | xfs_dir2_off_t newoff; /* new curoff after new blk */ | |
502 | char *ptr = NULL; /* pointer to current data */ | |
503 | struct xfs_dir2_leaf_map_info *map_info; | |
53f82db0 | 504 | struct xfs_da_geometry *geo = args->geo; |
4a8af273 DC |
505 | |
506 | /* | |
507 | * If the offset is at or past the largest allowed value, | |
508 | * give up right away. | |
509 | */ | |
510 | if (ctx->pos >= XFS_DIR2_MAX_DATAPTR) | |
511 | return 0; | |
512 | ||
4a8af273 DC |
513 | /* |
514 | * Set up to bmap a number of blocks based on the caller's | |
515 | * buffer size, the directory block size, and the filesystem | |
516 | * block size. | |
517 | */ | |
53f82db0 | 518 | length = howmany(bufsize + geo->blksize, (1 << geo->fsblog)); |
4a8af273 DC |
519 | map_info = kmem_zalloc(offsetof(struct xfs_dir2_leaf_map_info, map) + |
520 | (length * sizeof(struct xfs_bmbt_irec)), | |
521 | KM_SLEEP | KM_NOFS); | |
522 | map_info->map_size = length; | |
523 | ||
524 | /* | |
525 | * Inside the loop we keep the main offset value as a byte offset | |
526 | * in the directory file. | |
527 | */ | |
25994053 | 528 | curoff = xfs_dir2_dataptr_to_byte(ctx->pos); |
4a8af273 DC |
529 | |
530 | /* | |
531 | * Force this conversion through db so we truncate the offset | |
532 | * down to get the start of the data block. | |
533 | */ | |
30028030 DC |
534 | map_info->map_off = xfs_dir2_db_to_da(geo, |
535 | xfs_dir2_byte_to_db(geo, curoff)); | |
4a8af273 DC |
536 | |
537 | /* | |
538 | * Loop over directory entries until we reach the end offset. | |
539 | * Get more blocks and readahead as necessary. | |
540 | */ | |
541 | while (curoff < XFS_DIR2_LEAF_OFFSET) { | |
0cb97766 DC |
542 | __uint8_t filetype; |
543 | ||
4a8af273 DC |
544 | /* |
545 | * If we have no buffer, or we're off the end of the | |
546 | * current buffer, need to get another one. | |
547 | */ | |
8f66193c | 548 | if (!bp || ptr >= (char *)bp->b_addr + geo->blksize) { |
4a8af273 | 549 | |
53f82db0 | 550 | error = xfs_dir2_leaf_readbuf(args, bufsize, map_info, |
4a8af273 DC |
551 | &curoff, &bp); |
552 | if (error || !map_info->map_valid) | |
553 | break; | |
554 | ||
555 | /* | |
556 | * Having done a read, we need to set a new offset. | |
557 | */ | |
53f82db0 | 558 | newoff = xfs_dir2_db_off_to_byte(geo, |
9b3b5522 | 559 | map_info->curdb, 0); |
4a8af273 DC |
560 | /* |
561 | * Start of the current block. | |
562 | */ | |
563 | if (curoff < newoff) | |
564 | curoff = newoff; | |
565 | /* | |
566 | * Make sure we're in the right block. | |
567 | */ | |
568 | else if (curoff > newoff) | |
30028030 | 569 | ASSERT(xfs_dir2_byte_to_db(geo, curoff) == |
4a8af273 DC |
570 | map_info->curdb); |
571 | hdr = bp->b_addr; | |
572 | xfs_dir3_data_check(dp, bp); | |
573 | /* | |
574 | * Find our position in the block. | |
575 | */ | |
2ca98774 | 576 | ptr = (char *)dp->d_ops->data_entry_p(hdr); |
53f82db0 | 577 | byteoff = xfs_dir2_byte_to_off(geo, curoff); |
4a8af273 DC |
578 | /* |
579 | * Skip past the header. | |
580 | */ | |
581 | if (byteoff == 0) | |
1c9a5b2e | 582 | curoff += dp->d_ops->data_entry_offset; |
4a8af273 DC |
583 | /* |
584 | * Skip past entries until we reach our offset. | |
585 | */ | |
586 | else { | |
587 | while ((char *)ptr - (char *)hdr < byteoff) { | |
588 | dup = (xfs_dir2_data_unused_t *)ptr; | |
589 | ||
590 | if (be16_to_cpu(dup->freetag) | |
591 | == XFS_DIR2_DATA_FREE_TAG) { | |
592 | ||
593 | length = be16_to_cpu(dup->length); | |
594 | ptr += length; | |
595 | continue; | |
596 | } | |
597 | dep = (xfs_dir2_data_entry_t *)ptr; | |
598 | length = | |
9d23fc85 | 599 | dp->d_ops->data_entsize(dep->namelen); |
4a8af273 DC |
600 | ptr += length; |
601 | } | |
602 | /* | |
603 | * Now set our real offset. | |
604 | */ | |
605 | curoff = | |
30028030 DC |
606 | xfs_dir2_db_off_to_byte(geo, |
607 | xfs_dir2_byte_to_db(geo, curoff), | |
4a8af273 | 608 | (char *)ptr - (char *)hdr); |
8f66193c | 609 | if (ptr >= (char *)hdr + geo->blksize) { |
4a8af273 DC |
610 | continue; |
611 | } | |
612 | } | |
613 | } | |
614 | /* | |
615 | * We have a pointer to an entry. | |
616 | * Is it a live one? | |
617 | */ | |
618 | dup = (xfs_dir2_data_unused_t *)ptr; | |
619 | /* | |
620 | * No, it's unused, skip over it. | |
621 | */ | |
622 | if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) { | |
623 | length = be16_to_cpu(dup->length); | |
624 | ptr += length; | |
625 | curoff += length; | |
626 | continue; | |
627 | } | |
628 | ||
629 | dep = (xfs_dir2_data_entry_t *)ptr; | |
9d23fc85 DC |
630 | length = dp->d_ops->data_entsize(dep->namelen); |
631 | filetype = dp->d_ops->data_get_ftype(dep); | |
4a8af273 | 632 | |
25994053 | 633 | ctx->pos = xfs_dir2_byte_to_dataptr(curoff) & 0x7fffffff; |
4a8af273 | 634 | if (!dir_emit(ctx, (char *)dep->name, dep->namelen, |
0cb97766 | 635 | be64_to_cpu(dep->inumber), |
53f82db0 | 636 | xfs_dir3_get_dtype(dp->i_mount, filetype))) |
4a8af273 DC |
637 | break; |
638 | ||
639 | /* | |
640 | * Advance to next entry in the block. | |
641 | */ | |
642 | ptr += length; | |
643 | curoff += length; | |
644 | /* bufsize may have just been a guess; don't go negative */ | |
645 | bufsize = bufsize > length ? bufsize - length : 0; | |
646 | } | |
647 | ||
648 | /* | |
649 | * All done. Set output offset value to current offset. | |
650 | */ | |
25994053 | 651 | if (curoff > xfs_dir2_dataptr_to_byte(XFS_DIR2_MAX_DATAPTR)) |
4a8af273 DC |
652 | ctx->pos = XFS_DIR2_MAX_DATAPTR & 0x7fffffff; |
653 | else | |
25994053 | 654 | ctx->pos = xfs_dir2_byte_to_dataptr(curoff) & 0x7fffffff; |
4a8af273 DC |
655 | kmem_free(map_info); |
656 | if (bp) | |
657 | xfs_trans_brelse(NULL, bp); | |
658 | return error; | |
659 | } | |
660 | ||
661 | /* | |
662 | * Read a directory. | |
663 | */ | |
664 | int | |
665 | xfs_readdir( | |
53f82db0 DC |
666 | struct xfs_inode *dp, |
667 | struct dir_context *ctx, | |
668 | size_t bufsize) | |
4a8af273 | 669 | { |
35f46c5f | 670 | struct xfs_da_args args = { NULL }; |
53f82db0 DC |
671 | int rval; |
672 | int v; | |
673 | uint lock_mode; | |
4a8af273 DC |
674 | |
675 | trace_xfs_readdir(dp); | |
676 | ||
677 | if (XFS_FORCED_SHUTDOWN(dp->i_mount)) | |
2451337d | 678 | return -EIO; |
4a8af273 DC |
679 | |
680 | ASSERT(S_ISDIR(dp->i_d.di_mode)); | |
681 | XFS_STATS_INC(xs_dir_getdents); | |
682 | ||
53f82db0 DC |
683 | args.dp = dp; |
684 | args.geo = dp->i_mount->m_dir_geo; | |
685 | ||
40194ecc | 686 | lock_mode = xfs_ilock_data_map_shared(dp); |
4a8af273 | 687 | if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL) |
53f82db0 DC |
688 | rval = xfs_dir2_sf_getdents(&args, ctx); |
689 | else if ((rval = xfs_dir2_isblock(&args, &v))) | |
4a8af273 DC |
690 | ; |
691 | else if (v) | |
53f82db0 | 692 | rval = xfs_dir2_block_getdents(&args, ctx); |
4a8af273 | 693 | else |
53f82db0 | 694 | rval = xfs_dir2_leaf_getdents(&args, ctx, bufsize); |
40194ecc BM |
695 | xfs_iunlock(dp, lock_mode); |
696 | ||
4a8af273 DC |
697 | return rval; |
698 | } |