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"
21 #include "xfs_format.h"
22 #include "xfs_log_format.h"
23 #include "xfs_trans_resv.h"
24 #include "xfs_bit.h"
25 #include "xfs_sb.h"
26 #include "xfs_ag.h"
27 #include "xfs_mount.h"
28 #include "xfs_da_format.h"
29 #include "xfs_da_btree.h"
30 #include "xfs_inode.h"
31 #include "xfs_dir2.h"
32 #include "xfs_dir2_priv.h"
33 #include "xfs_error.h"
34 #include "xfs_trace.h"
35 #include "xfs_bmap.h"
36 #include "xfs_trans.h"
37 #include "xfs_dinode.h"
38
39 /*
40 * Directory file type support functions
41 */
42 static unsigned char xfs_dir3_filetype_table[] = {
43 DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK,
44 DT_FIFO, DT_SOCK, DT_LNK, DT_WHT,
45 };
46
47 unsigned char
xfs_dir3_get_dtype(struct xfs_mount * mp,__uint8_t filetype)48 xfs_dir3_get_dtype(
49 struct xfs_mount *mp,
50 __uint8_t filetype)
51 {
52 if (!xfs_sb_version_hasftype(&mp->m_sb))
53 return DT_UNKNOWN;
54
55 if (filetype >= XFS_DIR3_FT_MAX)
56 return DT_UNKNOWN;
57
58 return xfs_dir3_filetype_table[filetype];
59 }
60 /*
61 * @mode, if set, indicates that the type field needs to be set up.
62 * This uses the transformation from file mode to DT_* as defined in linux/fs.h
63 * for file type specification. This will be propagated into the directory
64 * structure if appropriate for the given operation and filesystem config.
65 */
66 const unsigned char xfs_mode_to_ftype[S_IFMT >> S_SHIFT] = {
67 [0] = XFS_DIR3_FT_UNKNOWN,
68 [S_IFREG >> S_SHIFT] = XFS_DIR3_FT_REG_FILE,
69 [S_IFDIR >> S_SHIFT] = XFS_DIR3_FT_DIR,
70 [S_IFCHR >> S_SHIFT] = XFS_DIR3_FT_CHRDEV,
71 [S_IFBLK >> S_SHIFT] = XFS_DIR3_FT_BLKDEV,
72 [S_IFIFO >> S_SHIFT] = XFS_DIR3_FT_FIFO,
73 [S_IFSOCK >> S_SHIFT] = XFS_DIR3_FT_SOCK,
74 [S_IFLNK >> S_SHIFT] = XFS_DIR3_FT_SYMLINK,
75 };
76
77 STATIC int
xfs_dir2_sf_getdents(struct xfs_da_args * args,struct dir_context * ctx)78 xfs_dir2_sf_getdents(
79 struct xfs_da_args *args,
80 struct dir_context *ctx)
81 {
82 int i; /* shortform entry number */
83 struct xfs_inode *dp = args->dp; /* incore directory inode */
84 xfs_dir2_dataptr_t off; /* current entry's offset */
85 xfs_dir2_sf_entry_t *sfep; /* shortform directory entry */
86 xfs_dir2_sf_hdr_t *sfp; /* shortform structure */
87 xfs_dir2_dataptr_t dot_offset;
88 xfs_dir2_dataptr_t dotdot_offset;
89 xfs_ino_t ino;
90 struct xfs_da_geometry *geo = args->geo;
91
92 ASSERT(dp->i_df.if_flags & XFS_IFINLINE);
93 /*
94 * Give up if the directory is way too short.
95 */
96 if (dp->i_d.di_size < offsetof(xfs_dir2_sf_hdr_t, parent)) {
97 ASSERT(XFS_FORCED_SHUTDOWN(dp->i_mount));
98 return -EIO;
99 }
100
101 ASSERT(dp->i_df.if_bytes == dp->i_d.di_size);
102 ASSERT(dp->i_df.if_u1.if_data != NULL);
103
104 sfp = (xfs_dir2_sf_hdr_t *)dp->i_df.if_u1.if_data;
105
106 ASSERT(dp->i_d.di_size >= xfs_dir2_sf_hdr_size(sfp->i8count));
107
108 /*
109 * If the block number in the offset is out of range, we're done.
110 */
111 if (xfs_dir2_dataptr_to_db(geo, ctx->pos) > geo->datablk)
112 return 0;
113
114 /*
115 * Precalculate offsets for . and .. as we will always need them.
116 *
117 * XXX(hch): the second argument is sometimes 0 and sometimes
118 * geo->datablk
119 */
120 dot_offset = xfs_dir2_db_off_to_dataptr(geo, geo->datablk,
121 dp->d_ops->data_dot_offset);
122 dotdot_offset = xfs_dir2_db_off_to_dataptr(geo, geo->datablk,
123 dp->d_ops->data_dotdot_offset);
124
125 /*
126 * Put . entry unless we're starting past it.
127 */
128 if (ctx->pos <= dot_offset) {
129 ctx->pos = dot_offset & 0x7fffffff;
130 if (!dir_emit(ctx, ".", 1, dp->i_ino, DT_DIR))
131 return 0;
132 }
133
134 /*
135 * Put .. entry unless we're starting past it.
136 */
137 if (ctx->pos <= dotdot_offset) {
138 ino = dp->d_ops->sf_get_parent_ino(sfp);
139 ctx->pos = dotdot_offset & 0x7fffffff;
140 if (!dir_emit(ctx, "..", 2, ino, DT_DIR))
141 return 0;
142 }
143
144 /*
145 * Loop while there are more entries and put'ing works.
146 */
147 sfep = xfs_dir2_sf_firstentry(sfp);
148 for (i = 0; i < sfp->count; i++) {
149 __uint8_t filetype;
150
151 off = xfs_dir2_db_off_to_dataptr(geo, geo->datablk,
152 xfs_dir2_sf_get_offset(sfep));
153
154 if (ctx->pos > off) {
155 sfep = dp->d_ops->sf_nextentry(sfp, sfep);
156 continue;
157 }
158
159 ino = dp->d_ops->sf_get_ino(sfp, sfep);
160 filetype = dp->d_ops->sf_get_ftype(sfep);
161 ctx->pos = off & 0x7fffffff;
162 if (!dir_emit(ctx, (char *)sfep->name, sfep->namelen, ino,
163 xfs_dir3_get_dtype(dp->i_mount, filetype)))
164 return 0;
165 sfep = dp->d_ops->sf_nextentry(sfp, sfep);
166 }
167
168 ctx->pos = xfs_dir2_db_off_to_dataptr(geo, geo->datablk + 1, 0) &
169 0x7fffffff;
170 return 0;
171 }
172
173 /*
174 * Readdir for block directories.
175 */
176 STATIC int
xfs_dir2_block_getdents(struct xfs_da_args * args,struct dir_context * ctx)177 xfs_dir2_block_getdents(
178 struct xfs_da_args *args,
179 struct dir_context *ctx)
180 {
181 struct xfs_inode *dp = args->dp; /* incore directory inode */
182 xfs_dir2_data_hdr_t *hdr; /* block header */
183 struct xfs_buf *bp; /* buffer for block */
184 xfs_dir2_block_tail_t *btp; /* block tail */
185 xfs_dir2_data_entry_t *dep; /* block data entry */
186 xfs_dir2_data_unused_t *dup; /* block unused entry */
187 char *endptr; /* end of the data entries */
188 int error; /* error return value */
189 char *ptr; /* current data entry */
190 int wantoff; /* starting block offset */
191 xfs_off_t cook;
192 struct xfs_da_geometry *geo = args->geo;
193
194 /*
195 * If the block number in the offset is out of range, we're done.
196 */
197 if (xfs_dir2_dataptr_to_db(geo, ctx->pos) > geo->datablk)
198 return 0;
199
200 error = xfs_dir3_block_read(NULL, dp, &bp);
201 if (error)
202 return error;
203
204 /*
205 * Extract the byte offset we start at from the seek pointer.
206 * We'll skip entries before this.
207 */
208 wantoff = xfs_dir2_dataptr_to_off(geo, ctx->pos);
209 hdr = bp->b_addr;
210 xfs_dir3_data_check(dp, bp);
211 /*
212 * Set up values for the loop.
213 */
214 btp = xfs_dir2_block_tail_p(geo, hdr);
215 ptr = (char *)dp->d_ops->data_entry_p(hdr);
216 endptr = (char *)xfs_dir2_block_leaf_p(btp);
217
218 /*
219 * Loop over the data portion of the block.
220 * Each object is a real entry (dep) or an unused one (dup).
221 */
222 while (ptr < endptr) {
223 __uint8_t filetype;
224
225 dup = (xfs_dir2_data_unused_t *)ptr;
226 /*
227 * Unused, skip it.
228 */
229 if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
230 ptr += be16_to_cpu(dup->length);
231 continue;
232 }
233
234 dep = (xfs_dir2_data_entry_t *)ptr;
235
236 /*
237 * Bump pointer for the next iteration.
238 */
239 ptr += dp->d_ops->data_entsize(dep->namelen);
240 /*
241 * The entry is before the desired starting point, skip it.
242 */
243 if ((char *)dep - (char *)hdr < wantoff)
244 continue;
245
246 cook = xfs_dir2_db_off_to_dataptr(geo, geo->datablk,
247 (char *)dep - (char *)hdr);
248
249 ctx->pos = cook & 0x7fffffff;
250 filetype = dp->d_ops->data_get_ftype(dep);
251 /*
252 * If it didn't fit, set the final offset to here & return.
253 */
254 if (!dir_emit(ctx, (char *)dep->name, dep->namelen,
255 be64_to_cpu(dep->inumber),
256 xfs_dir3_get_dtype(dp->i_mount, filetype))) {
257 xfs_trans_brelse(NULL, bp);
258 return 0;
259 }
260 }
261
262 /*
263 * Reached the end of the block.
264 * Set the offset to a non-existent block 1 and return.
265 */
266 ctx->pos = xfs_dir2_db_off_to_dataptr(geo, geo->datablk + 1, 0) &
267 0x7fffffff;
268 xfs_trans_brelse(NULL, bp);
269 return 0;
270 }
271
272 struct xfs_dir2_leaf_map_info {
273 xfs_extlen_t map_blocks; /* number of fsbs in map */
274 xfs_dablk_t map_off; /* last mapped file offset */
275 int map_size; /* total entries in *map */
276 int map_valid; /* valid entries in *map */
277 int nmap; /* mappings to ask xfs_bmapi */
278 xfs_dir2_db_t curdb; /* db for current block */
279 int ra_current; /* number of read-ahead blks */
280 int ra_index; /* *map index for read-ahead */
281 int ra_offset; /* map entry offset for ra */
282 int ra_want; /* readahead count wanted */
283 struct xfs_bmbt_irec map[]; /* map vector for blocks */
284 };
285
286 STATIC int
xfs_dir2_leaf_readbuf(struct xfs_da_args * args,size_t bufsize,struct xfs_dir2_leaf_map_info * mip,xfs_dir2_off_t * curoff,struct xfs_buf ** bpp)287 xfs_dir2_leaf_readbuf(
288 struct xfs_da_args *args,
289 size_t bufsize,
290 struct xfs_dir2_leaf_map_info *mip,
291 xfs_dir2_off_t *curoff,
292 struct xfs_buf **bpp)
293 {
294 struct xfs_inode *dp = args->dp;
295 struct xfs_buf *bp = *bpp;
296 struct xfs_bmbt_irec *map = mip->map;
297 struct blk_plug plug;
298 int error = 0;
299 int length;
300 int i;
301 int j;
302 struct xfs_da_geometry *geo = args->geo;
303
304 /*
305 * If we have a buffer, we need to release it and
306 * take it out of the mapping.
307 */
308
309 if (bp) {
310 xfs_trans_brelse(NULL, bp);
311 bp = NULL;
312 mip->map_blocks -= geo->fsbcount;
313 /*
314 * Loop to get rid of the extents for the
315 * directory block.
316 */
317 for (i = geo->fsbcount; i > 0; ) {
318 j = min_t(int, map->br_blockcount, i);
319 map->br_blockcount -= j;
320 map->br_startblock += j;
321 map->br_startoff += j;
322 /*
323 * If mapping is done, pitch it from
324 * the table.
325 */
326 if (!map->br_blockcount && --mip->map_valid)
327 memmove(&map[0], &map[1],
328 sizeof(map[0]) * mip->map_valid);
329 i -= j;
330 }
331 }
332
333 /*
334 * Recalculate the readahead blocks wanted.
335 */
336 mip->ra_want = howmany(bufsize + geo->blksize, (1 << geo->fsblog)) - 1;
337 ASSERT(mip->ra_want >= 0);
338
339 /*
340 * If we don't have as many as we want, and we haven't
341 * run out of data blocks, get some more mappings.
342 */
343 if (1 + mip->ra_want > mip->map_blocks &&
344 mip->map_off < xfs_dir2_byte_to_da(geo, XFS_DIR2_LEAF_OFFSET)) {
345 /*
346 * Get more bmaps, fill in after the ones
347 * we already have in the table.
348 */
349 mip->nmap = mip->map_size - mip->map_valid;
350 error = xfs_bmapi_read(dp, mip->map_off,
351 xfs_dir2_byte_to_da(geo, XFS_DIR2_LEAF_OFFSET) -
352 mip->map_off,
353 &map[mip->map_valid], &mip->nmap, 0);
354
355 /*
356 * Don't know if we should ignore this or try to return an
357 * error. The trouble with returning errors is that readdir
358 * will just stop without actually passing the error through.
359 */
360 if (error)
361 goto out; /* XXX */
362
363 /*
364 * If we got all the mappings we asked for, set the final map
365 * offset based on the last bmap value received. Otherwise,
366 * we've reached the end.
367 */
368 if (mip->nmap == mip->map_size - mip->map_valid) {
369 i = mip->map_valid + mip->nmap - 1;
370 mip->map_off = map[i].br_startoff + map[i].br_blockcount;
371 } else
372 mip->map_off = xfs_dir2_byte_to_da(geo,
373 XFS_DIR2_LEAF_OFFSET);
374
375 /*
376 * Look for holes in the mapping, and eliminate them. Count up
377 * the valid blocks.
378 */
379 for (i = mip->map_valid; i < mip->map_valid + mip->nmap; ) {
380 if (map[i].br_startblock == HOLESTARTBLOCK) {
381 mip->nmap--;
382 length = mip->map_valid + mip->nmap - i;
383 if (length)
384 memmove(&map[i], &map[i + 1],
385 sizeof(map[i]) * length);
386 } else {
387 mip->map_blocks += map[i].br_blockcount;
388 i++;
389 }
390 }
391 mip->map_valid += mip->nmap;
392 }
393
394 /*
395 * No valid mappings, so no more data blocks.
396 */
397 if (!mip->map_valid) {
398 *curoff = xfs_dir2_da_to_byte(geo, mip->map_off);
399 goto out;
400 }
401
402 /*
403 * Read the directory block starting at the first mapping.
404 */
405 mip->curdb = xfs_dir2_da_to_db(geo, map->br_startoff);
406 error = xfs_dir3_data_read(NULL, dp, map->br_startoff,
407 map->br_blockcount >= geo->fsbcount ?
408 XFS_FSB_TO_DADDR(dp->i_mount, map->br_startblock) :
409 -1, &bp);
410 /*
411 * Should just skip over the data block instead of giving up.
412 */
413 if (error)
414 goto out; /* XXX */
415
416 /*
417 * Adjust the current amount of read-ahead: we just read a block that
418 * was previously ra.
419 */
420 if (mip->ra_current)
421 mip->ra_current -= geo->fsbcount;
422
423 /*
424 * Do we need more readahead?
425 * Each loop tries to process 1 full dir blk; last may be partial.
426 */
427 blk_start_plug(&plug);
428 for (mip->ra_index = mip->ra_offset = i = 0;
429 mip->ra_want > mip->ra_current && i < mip->map_blocks;
430 i += geo->fsbcount) {
431 ASSERT(mip->ra_index < mip->map_valid);
432 /*
433 * Read-ahead a contiguous directory block.
434 */
435 if (i > mip->ra_current &&
436 (map[mip->ra_index].br_blockcount - mip->ra_offset) >=
437 geo->fsbcount) {
438 xfs_dir3_data_readahead(dp,
439 map[mip->ra_index].br_startoff + mip->ra_offset,
440 XFS_FSB_TO_DADDR(dp->i_mount,
441 map[mip->ra_index].br_startblock +
442 mip->ra_offset));
443 mip->ra_current = i;
444 }
445
446 /*
447 * Read-ahead a non-contiguous directory block. This doesn't
448 * use our mapping, but this is a very rare case.
449 */
450 else if (i > mip->ra_current) {
451 xfs_dir3_data_readahead(dp,
452 map[mip->ra_index].br_startoff +
453 mip->ra_offset, -1);
454 mip->ra_current = i;
455 }
456
457 /*
458 * Advance offset through the mapping table, processing a full
459 * dir block even if it is fragmented into several extents.
460 * But stop if we have consumed all valid mappings, even if
461 * it's not yet a full directory block.
462 */
463 for (j = 0;
464 j < geo->fsbcount && mip->ra_index < mip->map_valid;
465 j += length ) {
466 /*
467 * The rest of this extent but not more than a dir
468 * block.
469 */
470 length = min_t(int, geo->fsbcount - j,
471 map[mip->ra_index].br_blockcount -
472 mip->ra_offset);
473 mip->ra_offset += length;
474
475 /*
476 * Advance to the next mapping if this one is used up.
477 */
478 if (mip->ra_offset == map[mip->ra_index].br_blockcount) {
479 mip->ra_offset = 0;
480 mip->ra_index++;
481 }
482 }
483 }
484 blk_finish_plug(&plug);
485
486 out:
487 *bpp = bp;
488 return error;
489 }
490
491 /*
492 * Getdents (readdir) for leaf and node directories.
493 * This reads the data blocks only, so is the same for both forms.
494 */
495 STATIC int
xfs_dir2_leaf_getdents(struct xfs_da_args * args,struct dir_context * ctx,size_t bufsize)496 xfs_dir2_leaf_getdents(
497 struct xfs_da_args *args,
498 struct dir_context *ctx,
499 size_t bufsize)
500 {
501 struct xfs_inode *dp = args->dp;
502 struct xfs_buf *bp = NULL; /* data block buffer */
503 xfs_dir2_data_hdr_t *hdr; /* data block header */
504 xfs_dir2_data_entry_t *dep; /* data entry */
505 xfs_dir2_data_unused_t *dup; /* unused entry */
506 int error = 0; /* error return value */
507 int length; /* temporary length value */
508 int byteoff; /* offset in current block */
509 xfs_dir2_off_t curoff; /* current overall offset */
510 xfs_dir2_off_t newoff; /* new curoff after new blk */
511 char *ptr = NULL; /* pointer to current data */
512 struct xfs_dir2_leaf_map_info *map_info;
513 struct xfs_da_geometry *geo = args->geo;
514
515 /*
516 * If the offset is at or past the largest allowed value,
517 * give up right away.
518 */
519 if (ctx->pos >= XFS_DIR2_MAX_DATAPTR)
520 return 0;
521
522 /*
523 * Set up to bmap a number of blocks based on the caller's
524 * buffer size, the directory block size, and the filesystem
525 * block size.
526 */
527 length = howmany(bufsize + geo->blksize, (1 << geo->fsblog));
528 map_info = kmem_zalloc(offsetof(struct xfs_dir2_leaf_map_info, map) +
529 (length * sizeof(struct xfs_bmbt_irec)),
530 KM_SLEEP | KM_NOFS);
531 map_info->map_size = length;
532
533 /*
534 * Inside the loop we keep the main offset value as a byte offset
535 * in the directory file.
536 */
537 curoff = xfs_dir2_dataptr_to_byte(ctx->pos);
538
539 /*
540 * Force this conversion through db so we truncate the offset
541 * down to get the start of the data block.
542 */
543 map_info->map_off = xfs_dir2_db_to_da(geo,
544 xfs_dir2_byte_to_db(geo, curoff));
545
546 /*
547 * Loop over directory entries until we reach the end offset.
548 * Get more blocks and readahead as necessary.
549 */
550 while (curoff < XFS_DIR2_LEAF_OFFSET) {
551 __uint8_t filetype;
552
553 /*
554 * If we have no buffer, or we're off the end of the
555 * current buffer, need to get another one.
556 */
557 if (!bp || ptr >= (char *)bp->b_addr + geo->blksize) {
558
559 error = xfs_dir2_leaf_readbuf(args, bufsize, map_info,
560 &curoff, &bp);
561 if (error || !map_info->map_valid)
562 break;
563
564 /*
565 * Having done a read, we need to set a new offset.
566 */
567 newoff = xfs_dir2_db_off_to_byte(geo,
568 map_info->curdb, 0);
569 /*
570 * Start of the current block.
571 */
572 if (curoff < newoff)
573 curoff = newoff;
574 /*
575 * Make sure we're in the right block.
576 */
577 else if (curoff > newoff)
578 ASSERT(xfs_dir2_byte_to_db(geo, curoff) ==
579 map_info->curdb);
580 hdr = bp->b_addr;
581 xfs_dir3_data_check(dp, bp);
582 /*
583 * Find our position in the block.
584 */
585 ptr = (char *)dp->d_ops->data_entry_p(hdr);
586 byteoff = xfs_dir2_byte_to_off(geo, curoff);
587 /*
588 * Skip past the header.
589 */
590 if (byteoff == 0)
591 curoff += dp->d_ops->data_entry_offset;
592 /*
593 * Skip past entries until we reach our offset.
594 */
595 else {
596 while ((char *)ptr - (char *)hdr < byteoff) {
597 dup = (xfs_dir2_data_unused_t *)ptr;
598
599 if (be16_to_cpu(dup->freetag)
600 == XFS_DIR2_DATA_FREE_TAG) {
601
602 length = be16_to_cpu(dup->length);
603 ptr += length;
604 continue;
605 }
606 dep = (xfs_dir2_data_entry_t *)ptr;
607 length =
608 dp->d_ops->data_entsize(dep->namelen);
609 ptr += length;
610 }
611 /*
612 * Now set our real offset.
613 */
614 curoff =
615 xfs_dir2_db_off_to_byte(geo,
616 xfs_dir2_byte_to_db(geo, curoff),
617 (char *)ptr - (char *)hdr);
618 if (ptr >= (char *)hdr + geo->blksize) {
619 continue;
620 }
621 }
622 }
623 /*
624 * We have a pointer to an entry.
625 * Is it a live one?
626 */
627 dup = (xfs_dir2_data_unused_t *)ptr;
628 /*
629 * No, it's unused, skip over it.
630 */
631 if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
632 length = be16_to_cpu(dup->length);
633 ptr += length;
634 curoff += length;
635 continue;
636 }
637
638 dep = (xfs_dir2_data_entry_t *)ptr;
639 length = dp->d_ops->data_entsize(dep->namelen);
640 filetype = dp->d_ops->data_get_ftype(dep);
641
642 ctx->pos = xfs_dir2_byte_to_dataptr(curoff) & 0x7fffffff;
643 if (!dir_emit(ctx, (char *)dep->name, dep->namelen,
644 be64_to_cpu(dep->inumber),
645 xfs_dir3_get_dtype(dp->i_mount, filetype)))
646 break;
647
648 /*
649 * Advance to next entry in the block.
650 */
651 ptr += length;
652 curoff += length;
653 /* bufsize may have just been a guess; don't go negative */
654 bufsize = bufsize > length ? bufsize - length : 0;
655 }
656
657 /*
658 * All done. Set output offset value to current offset.
659 */
660 if (curoff > xfs_dir2_dataptr_to_byte(XFS_DIR2_MAX_DATAPTR))
661 ctx->pos = XFS_DIR2_MAX_DATAPTR & 0x7fffffff;
662 else
663 ctx->pos = xfs_dir2_byte_to_dataptr(curoff) & 0x7fffffff;
664 kmem_free(map_info);
665 if (bp)
666 xfs_trans_brelse(NULL, bp);
667 return error;
668 }
669
670 /*
671 * Read a directory.
672 */
673 int
xfs_readdir(struct xfs_inode * dp,struct dir_context * ctx,size_t bufsize)674 xfs_readdir(
675 struct xfs_inode *dp,
676 struct dir_context *ctx,
677 size_t bufsize)
678 {
679 struct xfs_da_args args = { NULL };
680 int rval;
681 int v;
682 uint lock_mode;
683
684 trace_xfs_readdir(dp);
685
686 if (XFS_FORCED_SHUTDOWN(dp->i_mount))
687 return -EIO;
688
689 ASSERT(S_ISDIR(dp->i_d.di_mode));
690 XFS_STATS_INC(xs_dir_getdents);
691
692 args.dp = dp;
693 args.geo = dp->i_mount->m_dir_geo;
694
695 lock_mode = xfs_ilock_data_map_shared(dp);
696 if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL)
697 rval = xfs_dir2_sf_getdents(&args, ctx);
698 else if ((rval = xfs_dir2_isblock(&args, &v)))
699 ;
700 else if (v)
701 rval = xfs_dir2_block_getdents(&args, ctx);
702 else
703 rval = xfs_dir2_leaf_getdents(&args, ctx, bufsize);
704 xfs_iunlock(dp, lock_mode);
705
706 return rval;
707 }
708