blob: f1b69edcdf310fc0342c0aff40bacfa2682f13c2 [file] [log] [blame]
Dave Chinner4a8af272013-08-12 20:49:36 +10001/*
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"
Dave Chinnera4fbe6a2013-10-23 10:51:50 +110021#include "xfs_format.h"
Dave Chinner239880e2013-10-23 10:50:10 +110022#include "xfs_log_format.h"
23#include "xfs_trans_resv.h"
Dave Chinner4a8af272013-08-12 20:49:36 +100024#include "xfs_bit.h"
Dave Chinner4a8af272013-08-12 20:49:36 +100025#include "xfs_sb.h"
26#include "xfs_ag.h"
27#include "xfs_mount.h"
Dave Chinner57062782013-10-15 09:17:51 +110028#include "xfs_da_format.h"
Dave Chinner4a8af272013-08-12 20:49:36 +100029#include "xfs_da_btree.h"
Dave Chinner4a8af272013-08-12 20:49:36 +100030#include "xfs_inode.h"
Dave Chinner2b9ab5a2013-08-12 20:49:37 +100031#include "xfs_dir2.h"
Dave Chinner4a8af272013-08-12 20:49:36 +100032#include "xfs_dir2_priv.h"
33#include "xfs_error.h"
34#include "xfs_trace.h"
35#include "xfs_bmap.h"
Dave Chinner239880e2013-10-23 10:50:10 +110036#include "xfs_trans.h"
Dave Chinnera4fbe6a2013-10-23 10:51:50 +110037#include "xfs_dinode.h"
Dave Chinner4a8af272013-08-12 20:49:36 +100038
Dave Chinner0cb97762013-08-12 20:50:09 +100039/*
40 * Directory file type support functions
41 */
42static 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
47unsigned char
48xfs_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 */
66const 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
Dave Chinner4a8af272013-08-12 20:49:36 +100077STATIC int
78xfs_dir2_sf_getdents(
Dave Chinner53f82db2014-06-06 15:20:32 +100079 struct xfs_da_args *args,
Dave Chinner4a8af272013-08-12 20:49:36 +100080 struct dir_context *ctx)
81{
82 int i; /* shortform entry number */
Dave Chinner53f82db2014-06-06 15:20:32 +100083 struct xfs_inode *dp = args->dp; /* incore directory inode */
Dave Chinner4a8af272013-08-12 20:49:36 +100084 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;
Dave Chinner53f82db2014-06-06 15:20:32 +100090 struct xfs_da_geometry *geo = args->geo;
Dave Chinner4a8af272013-08-12 20:49:36 +100091
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)) {
Dave Chinner53f82db2014-06-06 15:20:32 +100097 ASSERT(XFS_FORCED_SHUTDOWN(dp->i_mount));
Dave Chinner24513372014-06-25 14:58:08 +100098 return -EIO;
Dave Chinner4a8af272013-08-12 20:49:36 +100099 }
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 */
Dave Chinner7dda6e82014-06-06 15:11:18 +1000111 if (xfs_dir2_dataptr_to_db(geo, ctx->pos) > geo->datablk)
Dave Chinner4a8af272013-08-12 20:49:36 +1000112 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
Dave Chinner7dda6e82014-06-06 15:11:18 +1000118 * geo->datablk
Dave Chinner4a8af272013-08-12 20:49:36 +1000119 */
Dave Chinner7dda6e82014-06-06 15:11:18 +1000120 dot_offset = xfs_dir2_db_off_to_dataptr(geo, geo->datablk,
Dave Chinner1c9a5b22013-10-30 09:15:02 +1100121 dp->d_ops->data_dot_offset);
Dave Chinner7dda6e82014-06-06 15:11:18 +1000122 dotdot_offset = xfs_dir2_db_off_to_dataptr(geo, geo->datablk,
Dave Chinner1c9a5b22013-10-30 09:15:02 +1100123 dp->d_ops->data_dotdot_offset);
Dave Chinner4a8af272013-08-12 20:49:36 +1000124
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) {
Dave Chinner47401752013-10-29 22:11:47 +1100138 ino = dp->d_ops->sf_get_parent_ino(sfp);
Dave Chinner4a8af272013-08-12 20:49:36 +1000139 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++) {
Dave Chinner0cb97762013-08-12 20:50:09 +1000149 __uint8_t filetype;
150
Dave Chinner7dda6e82014-06-06 15:11:18 +1000151 off = xfs_dir2_db_off_to_dataptr(geo, geo->datablk,
Dave Chinner4a8af272013-08-12 20:49:36 +1000152 xfs_dir2_sf_get_offset(sfep));
153
154 if (ctx->pos > off) {
Dave Chinner32c54832013-10-29 22:11:46 +1100155 sfep = dp->d_ops->sf_nextentry(sfp, sfep);
Dave Chinner4a8af272013-08-12 20:49:36 +1000156 continue;
157 }
158
Dave Chinner47401752013-10-29 22:11:47 +1100159 ino = dp->d_ops->sf_get_ino(sfp, sfep);
160 filetype = dp->d_ops->sf_get_ftype(sfep);
Dave Chinner4a8af272013-08-12 20:49:36 +1000161 ctx->pos = off & 0x7fffffff;
Dave Chinner0cb97762013-08-12 20:50:09 +1000162 if (!dir_emit(ctx, (char *)sfep->name, sfep->namelen, ino,
Dave Chinner53f82db2014-06-06 15:20:32 +1000163 xfs_dir3_get_dtype(dp->i_mount, filetype)))
Dave Chinner4a8af272013-08-12 20:49:36 +1000164 return 0;
Dave Chinner32c54832013-10-29 22:11:46 +1100165 sfep = dp->d_ops->sf_nextentry(sfp, sfep);
Dave Chinner4a8af272013-08-12 20:49:36 +1000166 }
167
Dave Chinner7dda6e82014-06-06 15:11:18 +1000168 ctx->pos = xfs_dir2_db_off_to_dataptr(geo, geo->datablk + 1, 0) &
Dave Chinner53f82db2014-06-06 15:20:32 +1000169 0x7fffffff;
Dave Chinner4a8af272013-08-12 20:49:36 +1000170 return 0;
171}
172
173/*
174 * Readdir for block directories.
175 */
176STATIC int
177xfs_dir2_block_getdents(
Dave Chinner53f82db2014-06-06 15:20:32 +1000178 struct xfs_da_args *args,
Dave Chinner4a8af272013-08-12 20:49:36 +1000179 struct dir_context *ctx)
180{
Dave Chinner53f82db2014-06-06 15:20:32 +1000181 struct xfs_inode *dp = args->dp; /* incore directory inode */
Dave Chinner4a8af272013-08-12 20:49:36 +1000182 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 */
Dave Chinner4a8af272013-08-12 20:49:36 +1000189 char *ptr; /* current data entry */
190 int wantoff; /* starting block offset */
191 xfs_off_t cook;
Dave Chinner53f82db2014-06-06 15:20:32 +1000192 struct xfs_da_geometry *geo = args->geo;
Dave Chinner4a8af272013-08-12 20:49:36 +1000193
Dave Chinner4a8af272013-08-12 20:49:36 +1000194 /*
195 * If the block number in the offset is out of range, we're done.
196 */
Dave Chinner7dda6e82014-06-06 15:11:18 +1000197 if (xfs_dir2_dataptr_to_db(geo, ctx->pos) > geo->datablk)
Dave Chinner4a8af272013-08-12 20:49:36 +1000198 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 */
Dave Chinner30028032014-06-06 15:08:18 +1000208 wantoff = xfs_dir2_dataptr_to_off(geo, ctx->pos);
Dave Chinner4a8af272013-08-12 20:49:36 +1000209 hdr = bp->b_addr;
210 xfs_dir3_data_check(dp, bp);
211 /*
212 * Set up values for the loop.
213 */
Dave Chinner8f661932014-06-06 15:15:59 +1000214 btp = xfs_dir2_block_tail_p(geo, hdr);
Dave Chinner2ca98772013-10-29 22:11:49 +1100215 ptr = (char *)dp->d_ops->data_entry_p(hdr);
Dave Chinner4a8af272013-08-12 20:49:36 +1000216 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) {
Dave Chinner0cb97762013-08-12 20:50:09 +1000223 __uint8_t filetype;
224
Dave Chinner4a8af272013-08-12 20:49:36 +1000225 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 */
Dave Chinner9d23fc82013-10-29 22:11:48 +1100239 ptr += dp->d_ops->data_entsize(dep->namelen);
Dave Chinner4a8af272013-08-12 20:49:36 +1000240 /*
241 * The entry is before the desired starting point, skip it.
242 */
243 if ((char *)dep - (char *)hdr < wantoff)
244 continue;
245
Dave Chinner7dda6e82014-06-06 15:11:18 +1000246 cook = xfs_dir2_db_off_to_dataptr(geo, geo->datablk,
Dave Chinner4a8af272013-08-12 20:49:36 +1000247 (char *)dep - (char *)hdr);
248
249 ctx->pos = cook & 0x7fffffff;
Dave Chinner9d23fc82013-10-29 22:11:48 +1100250 filetype = dp->d_ops->data_get_ftype(dep);
Dave Chinner4a8af272013-08-12 20:49:36 +1000251 /*
252 * If it didn't fit, set the final offset to here & return.
253 */
254 if (!dir_emit(ctx, (char *)dep->name, dep->namelen,
Dave Chinner0cb97762013-08-12 20:50:09 +1000255 be64_to_cpu(dep->inumber),
Dave Chinner53f82db2014-06-06 15:20:32 +1000256 xfs_dir3_get_dtype(dp->i_mount, filetype))) {
Dave Chinner4a8af272013-08-12 20:49:36 +1000257 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 */
Dave Chinner7dda6e82014-06-06 15:11:18 +1000266 ctx->pos = xfs_dir2_db_off_to_dataptr(geo, geo->datablk + 1, 0) &
Dave Chinner53f82db2014-06-06 15:20:32 +1000267 0x7fffffff;
Dave Chinner4a8af272013-08-12 20:49:36 +1000268 xfs_trans_brelse(NULL, bp);
269 return 0;
270}
271
272struct 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
286STATIC int
287xfs_dir2_leaf_readbuf(
Dave Chinner53f82db2014-06-06 15:20:32 +1000288 struct xfs_da_args *args,
Dave Chinner4a8af272013-08-12 20:49:36 +1000289 size_t bufsize,
290 struct xfs_dir2_leaf_map_info *mip,
291 xfs_dir2_off_t *curoff,
292 struct xfs_buf **bpp)
293{
Dave Chinner53f82db2014-06-06 15:20:32 +1000294 struct xfs_inode *dp = args->dp;
Dave Chinner4a8af272013-08-12 20:49:36 +1000295 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;
Dave Chinner53f82db2014-06-06 15:20:32 +1000302 struct xfs_da_geometry *geo = args->geo;
Dave Chinner4a8af272013-08-12 20:49:36 +1000303
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;
Dave Chinnerd6cf1302014-06-06 15:14:11 +1000312 mip->map_blocks -= geo->fsbcount;
Dave Chinner4a8af272013-08-12 20:49:36 +1000313 /*
314 * Loop to get rid of the extents for the
315 * directory block.
316 */
Dave Chinnerd6cf1302014-06-06 15:14:11 +1000317 for (i = geo->fsbcount; i > 0; ) {
Dave Chinner4a8af272013-08-12 20:49:36 +1000318 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 */
Dave Chinner53f82db2014-06-06 15:20:32 +1000336 mip->ra_want = howmany(bufsize + geo->blksize, (1 << geo->fsblog)) - 1;
Dave Chinner4a8af272013-08-12 20:49:36 +1000337 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 &&
Dave Chinner30028032014-06-06 15:08:18 +1000344 mip->map_off < xfs_dir2_byte_to_da(geo, XFS_DIR2_LEAF_OFFSET)) {
Dave Chinner4a8af272013-08-12 20:49:36 +1000345 /*
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,
Dave Chinner30028032014-06-06 15:08:18 +1000351 xfs_dir2_byte_to_da(geo, XFS_DIR2_LEAF_OFFSET) -
Dave Chinner4a8af272013-08-12 20:49:36 +1000352 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
Dave Chinner30028032014-06-06 15:08:18 +1000372 mip->map_off = xfs_dir2_byte_to_da(geo,
Dave Chinner4a8af272013-08-12 20:49:36 +1000373 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) {
Dave Chinner30028032014-06-06 15:08:18 +1000398 *curoff = xfs_dir2_da_to_byte(geo, mip->map_off);
Dave Chinner4a8af272013-08-12 20:49:36 +1000399 goto out;
400 }
401
402 /*
403 * Read the directory block starting at the first mapping.
404 */
Dave Chinner30028032014-06-06 15:08:18 +1000405 mip->curdb = xfs_dir2_da_to_db(geo, map->br_startoff);
Dave Chinner4a8af272013-08-12 20:49:36 +1000406 error = xfs_dir3_data_read(NULL, dp, map->br_startoff,
Dave Chinnerd6cf1302014-06-06 15:14:11 +1000407 map->br_blockcount >= geo->fsbcount ?
Dave Chinner53f82db2014-06-06 15:20:32 +1000408 XFS_FSB_TO_DADDR(dp->i_mount, map->br_startblock) :
409 -1, &bp);
Dave Chinner4a8af272013-08-12 20:49:36 +1000410 /*
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)
Dave Chinnerd6cf1302014-06-06 15:14:11 +1000421 mip->ra_current -= geo->fsbcount;
Dave Chinner4a8af272013-08-12 20:49:36 +1000422
423 /*
424 * Do we need more readahead?
425 */
426 blk_start_plug(&plug);
427 for (mip->ra_index = mip->ra_offset = i = 0;
428 mip->ra_want > mip->ra_current && i < mip->map_blocks;
Dave Chinnerd6cf1302014-06-06 15:14:11 +1000429 i += geo->fsbcount) {
Dave Chinner4a8af272013-08-12 20:49:36 +1000430 ASSERT(mip->ra_index < mip->map_valid);
431 /*
432 * Read-ahead a contiguous directory block.
433 */
434 if (i > mip->ra_current &&
Dave Chinnerd6cf1302014-06-06 15:14:11 +1000435 map[mip->ra_index].br_blockcount >= geo->fsbcount) {
Eric Sandeen9df2dd02014-04-14 19:01:59 +1000436 xfs_dir3_data_readahead(dp,
Dave Chinner4a8af272013-08-12 20:49:36 +1000437 map[mip->ra_index].br_startoff + mip->ra_offset,
Dave Chinner53f82db2014-06-06 15:20:32 +1000438 XFS_FSB_TO_DADDR(dp->i_mount,
Dave Chinner4a8af272013-08-12 20:49:36 +1000439 map[mip->ra_index].br_startblock +
440 mip->ra_offset));
441 mip->ra_current = i;
442 }
443
444 /*
445 * Read-ahead a non-contiguous directory block. This doesn't
446 * use our mapping, but this is a very rare case.
447 */
448 else if (i > mip->ra_current) {
Eric Sandeen9df2dd02014-04-14 19:01:59 +1000449 xfs_dir3_data_readahead(dp,
Dave Chinner4a8af272013-08-12 20:49:36 +1000450 map[mip->ra_index].br_startoff +
451 mip->ra_offset, -1);
452 mip->ra_current = i;
453 }
454
455 /*
456 * Advance offset through the mapping table.
457 */
Dave Chinnerd6cf1302014-06-06 15:14:11 +1000458 for (j = 0; j < geo->fsbcount; j += length ) {
Dave Chinner4a8af272013-08-12 20:49:36 +1000459 /*
460 * The rest of this extent but not more than a dir
461 * block.
462 */
Dave Chinnerd6cf1302014-06-06 15:14:11 +1000463 length = min_t(int, geo->fsbcount,
Dave Chinner4a8af272013-08-12 20:49:36 +1000464 map[mip->ra_index].br_blockcount -
465 mip->ra_offset);
Dave Chinner4a8af272013-08-12 20:49:36 +1000466 mip->ra_offset += length;
467
468 /*
469 * Advance to the next mapping if this one is used up.
470 */
471 if (mip->ra_offset == map[mip->ra_index].br_blockcount) {
472 mip->ra_offset = 0;
473 mip->ra_index++;
474 }
475 }
476 }
477 blk_finish_plug(&plug);
478
479out:
480 *bpp = bp;
481 return error;
482}
483
484/*
485 * Getdents (readdir) for leaf and node directories.
486 * This reads the data blocks only, so is the same for both forms.
487 */
488STATIC int
489xfs_dir2_leaf_getdents(
Dave Chinner53f82db2014-06-06 15:20:32 +1000490 struct xfs_da_args *args,
Dave Chinner4a8af272013-08-12 20:49:36 +1000491 struct dir_context *ctx,
492 size_t bufsize)
493{
Dave Chinner53f82db2014-06-06 15:20:32 +1000494 struct xfs_inode *dp = args->dp;
Dave Chinner4a8af272013-08-12 20:49:36 +1000495 struct xfs_buf *bp = NULL; /* data block buffer */
496 xfs_dir2_data_hdr_t *hdr; /* data block header */
497 xfs_dir2_data_entry_t *dep; /* data entry */
498 xfs_dir2_data_unused_t *dup; /* unused entry */
499 int error = 0; /* error return value */
500 int length; /* temporary length value */
Dave Chinner4a8af272013-08-12 20:49:36 +1000501 int byteoff; /* offset in current block */
502 xfs_dir2_off_t curoff; /* current overall offset */
503 xfs_dir2_off_t newoff; /* new curoff after new blk */
504 char *ptr = NULL; /* pointer to current data */
505 struct xfs_dir2_leaf_map_info *map_info;
Dave Chinner53f82db2014-06-06 15:20:32 +1000506 struct xfs_da_geometry *geo = args->geo;
Dave Chinner4a8af272013-08-12 20:49:36 +1000507
508 /*
509 * If the offset is at or past the largest allowed value,
510 * give up right away.
511 */
512 if (ctx->pos >= XFS_DIR2_MAX_DATAPTR)
513 return 0;
514
Dave Chinner4a8af272013-08-12 20:49:36 +1000515 /*
516 * Set up to bmap a number of blocks based on the caller's
517 * buffer size, the directory block size, and the filesystem
518 * block size.
519 */
Dave Chinner53f82db2014-06-06 15:20:32 +1000520 length = howmany(bufsize + geo->blksize, (1 << geo->fsblog));
Dave Chinner4a8af272013-08-12 20:49:36 +1000521 map_info = kmem_zalloc(offsetof(struct xfs_dir2_leaf_map_info, map) +
522 (length * sizeof(struct xfs_bmbt_irec)),
523 KM_SLEEP | KM_NOFS);
524 map_info->map_size = length;
525
526 /*
527 * Inside the loop we keep the main offset value as a byte offset
528 * in the directory file.
529 */
Eric Sandeen25994052014-04-14 19:02:30 +1000530 curoff = xfs_dir2_dataptr_to_byte(ctx->pos);
Dave Chinner4a8af272013-08-12 20:49:36 +1000531
532 /*
533 * Force this conversion through db so we truncate the offset
534 * down to get the start of the data block.
535 */
Dave Chinner30028032014-06-06 15:08:18 +1000536 map_info->map_off = xfs_dir2_db_to_da(geo,
537 xfs_dir2_byte_to_db(geo, curoff));
Dave Chinner4a8af272013-08-12 20:49:36 +1000538
539 /*
540 * Loop over directory entries until we reach the end offset.
541 * Get more blocks and readahead as necessary.
542 */
543 while (curoff < XFS_DIR2_LEAF_OFFSET) {
Dave Chinner0cb97762013-08-12 20:50:09 +1000544 __uint8_t filetype;
545
Dave Chinner4a8af272013-08-12 20:49:36 +1000546 /*
547 * If we have no buffer, or we're off the end of the
548 * current buffer, need to get another one.
549 */
Dave Chinner8f661932014-06-06 15:15:59 +1000550 if (!bp || ptr >= (char *)bp->b_addr + geo->blksize) {
Dave Chinner4a8af272013-08-12 20:49:36 +1000551
Dave Chinner53f82db2014-06-06 15:20:32 +1000552 error = xfs_dir2_leaf_readbuf(args, bufsize, map_info,
Dave Chinner4a8af272013-08-12 20:49:36 +1000553 &curoff, &bp);
554 if (error || !map_info->map_valid)
555 break;
556
557 /*
558 * Having done a read, we need to set a new offset.
559 */
Dave Chinner53f82db2014-06-06 15:20:32 +1000560 newoff = xfs_dir2_db_off_to_byte(geo,
Dave Chinner9b3b5522014-06-06 15:06:53 +1000561 map_info->curdb, 0);
Dave Chinner4a8af272013-08-12 20:49:36 +1000562 /*
563 * Start of the current block.
564 */
565 if (curoff < newoff)
566 curoff = newoff;
567 /*
568 * Make sure we're in the right block.
569 */
570 else if (curoff > newoff)
Dave Chinner30028032014-06-06 15:08:18 +1000571 ASSERT(xfs_dir2_byte_to_db(geo, curoff) ==
Dave Chinner4a8af272013-08-12 20:49:36 +1000572 map_info->curdb);
573 hdr = bp->b_addr;
574 xfs_dir3_data_check(dp, bp);
575 /*
576 * Find our position in the block.
577 */
Dave Chinner2ca98772013-10-29 22:11:49 +1100578 ptr = (char *)dp->d_ops->data_entry_p(hdr);
Dave Chinner53f82db2014-06-06 15:20:32 +1000579 byteoff = xfs_dir2_byte_to_off(geo, curoff);
Dave Chinner4a8af272013-08-12 20:49:36 +1000580 /*
581 * Skip past the header.
582 */
583 if (byteoff == 0)
Dave Chinner1c9a5b22013-10-30 09:15:02 +1100584 curoff += dp->d_ops->data_entry_offset;
Dave Chinner4a8af272013-08-12 20:49:36 +1000585 /*
586 * Skip past entries until we reach our offset.
587 */
588 else {
589 while ((char *)ptr - (char *)hdr < byteoff) {
590 dup = (xfs_dir2_data_unused_t *)ptr;
591
592 if (be16_to_cpu(dup->freetag)
593 == XFS_DIR2_DATA_FREE_TAG) {
594
595 length = be16_to_cpu(dup->length);
596 ptr += length;
597 continue;
598 }
599 dep = (xfs_dir2_data_entry_t *)ptr;
600 length =
Dave Chinner9d23fc82013-10-29 22:11:48 +1100601 dp->d_ops->data_entsize(dep->namelen);
Dave Chinner4a8af272013-08-12 20:49:36 +1000602 ptr += length;
603 }
604 /*
605 * Now set our real offset.
606 */
607 curoff =
Dave Chinner30028032014-06-06 15:08:18 +1000608 xfs_dir2_db_off_to_byte(geo,
609 xfs_dir2_byte_to_db(geo, curoff),
Dave Chinner4a8af272013-08-12 20:49:36 +1000610 (char *)ptr - (char *)hdr);
Dave Chinner8f661932014-06-06 15:15:59 +1000611 if (ptr >= (char *)hdr + geo->blksize) {
Dave Chinner4a8af272013-08-12 20:49:36 +1000612 continue;
613 }
614 }
615 }
616 /*
617 * We have a pointer to an entry.
618 * Is it a live one?
619 */
620 dup = (xfs_dir2_data_unused_t *)ptr;
621 /*
622 * No, it's unused, skip over it.
623 */
624 if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
625 length = be16_to_cpu(dup->length);
626 ptr += length;
627 curoff += length;
628 continue;
629 }
630
631 dep = (xfs_dir2_data_entry_t *)ptr;
Dave Chinner9d23fc82013-10-29 22:11:48 +1100632 length = dp->d_ops->data_entsize(dep->namelen);
633 filetype = dp->d_ops->data_get_ftype(dep);
Dave Chinner4a8af272013-08-12 20:49:36 +1000634
Eric Sandeen25994052014-04-14 19:02:30 +1000635 ctx->pos = xfs_dir2_byte_to_dataptr(curoff) & 0x7fffffff;
Dave Chinner4a8af272013-08-12 20:49:36 +1000636 if (!dir_emit(ctx, (char *)dep->name, dep->namelen,
Dave Chinner0cb97762013-08-12 20:50:09 +1000637 be64_to_cpu(dep->inumber),
Dave Chinner53f82db2014-06-06 15:20:32 +1000638 xfs_dir3_get_dtype(dp->i_mount, filetype)))
Dave Chinner4a8af272013-08-12 20:49:36 +1000639 break;
640
641 /*
642 * Advance to next entry in the block.
643 */
644 ptr += length;
645 curoff += length;
646 /* bufsize may have just been a guess; don't go negative */
647 bufsize = bufsize > length ? bufsize - length : 0;
648 }
649
650 /*
651 * All done. Set output offset value to current offset.
652 */
Eric Sandeen25994052014-04-14 19:02:30 +1000653 if (curoff > xfs_dir2_dataptr_to_byte(XFS_DIR2_MAX_DATAPTR))
Dave Chinner4a8af272013-08-12 20:49:36 +1000654 ctx->pos = XFS_DIR2_MAX_DATAPTR & 0x7fffffff;
655 else
Eric Sandeen25994052014-04-14 19:02:30 +1000656 ctx->pos = xfs_dir2_byte_to_dataptr(curoff) & 0x7fffffff;
Dave Chinner4a8af272013-08-12 20:49:36 +1000657 kmem_free(map_info);
658 if (bp)
659 xfs_trans_brelse(NULL, bp);
660 return error;
661}
662
663/*
664 * Read a directory.
665 */
666int
667xfs_readdir(
Dave Chinner53f82db2014-06-06 15:20:32 +1000668 struct xfs_inode *dp,
669 struct dir_context *ctx,
670 size_t bufsize)
Dave Chinner4a8af272013-08-12 20:49:36 +1000671{
Dave Chinner35f46c52014-06-10 07:30:36 +1000672 struct xfs_da_args args = { NULL };
Dave Chinner53f82db2014-06-06 15:20:32 +1000673 int rval;
674 int v;
675 uint lock_mode;
Dave Chinner4a8af272013-08-12 20:49:36 +1000676
677 trace_xfs_readdir(dp);
678
679 if (XFS_FORCED_SHUTDOWN(dp->i_mount))
Dave Chinner24513372014-06-25 14:58:08 +1000680 return -EIO;
Dave Chinner4a8af272013-08-12 20:49:36 +1000681
682 ASSERT(S_ISDIR(dp->i_d.di_mode));
683 XFS_STATS_INC(xs_dir_getdents);
684
Dave Chinner53f82db2014-06-06 15:20:32 +1000685 args.dp = dp;
686 args.geo = dp->i_mount->m_dir_geo;
687
Ben Myers40194ec2013-12-06 12:30:11 -0800688 lock_mode = xfs_ilock_data_map_shared(dp);
Dave Chinner4a8af272013-08-12 20:49:36 +1000689 if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL)
Dave Chinner53f82db2014-06-06 15:20:32 +1000690 rval = xfs_dir2_sf_getdents(&args, ctx);
691 else if ((rval = xfs_dir2_isblock(&args, &v)))
Dave Chinner4a8af272013-08-12 20:49:36 +1000692 ;
693 else if (v)
Dave Chinner53f82db2014-06-06 15:20:32 +1000694 rval = xfs_dir2_block_getdents(&args, ctx);
Dave Chinner4a8af272013-08-12 20:49:36 +1000695 else
Dave Chinner53f82db2014-06-06 15:20:32 +1000696 rval = xfs_dir2_leaf_getdents(&args, ctx, bufsize);
Ben Myers40194ec2013-12-06 12:30:11 -0800697 xfs_iunlock(dp, lock_mode);
698
Dave Chinner4a8af272013-08-12 20:49:36 +1000699 return rval;
700}