blob: f44f7999697860ace70a6de316f81e76dee5bc08 [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_mount.h"
Dave Chinner57062782013-10-15 09:17:51 +110026#include "xfs_da_format.h"
Dave Chinner4a8af272013-08-12 20:49:36 +100027#include "xfs_da_btree.h"
Dave Chinner4a8af272013-08-12 20:49:36 +100028#include "xfs_inode.h"
Dave Chinner2b9ab5a2013-08-12 20:49:37 +100029#include "xfs_dir2.h"
Dave Chinner4a8af272013-08-12 20:49:36 +100030#include "xfs_dir2_priv.h"
31#include "xfs_error.h"
32#include "xfs_trace.h"
33#include "xfs_bmap.h"
Dave Chinner239880e2013-10-23 10:50:10 +110034#include "xfs_trans.h"
Dave Chinner4a8af272013-08-12 20:49:36 +100035
Dave Chinner0cb97762013-08-12 20:50:09 +100036/*
37 * Directory file type support functions
38 */
39static 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
Dave Chinner1b767ee2014-12-04 09:43:17 +110044static unsigned char
Dave Chinner0cb97762013-08-12 20:50:09 +100045xfs_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}
Dave Chinner0cb97762013-08-12 20:50:09 +100057
Dave Chinner4a8af272013-08-12 20:49:36 +100058STATIC int
59xfs_dir2_sf_getdents(
Dave Chinner53f82db2014-06-06 15:20:32 +100060 struct xfs_da_args *args,
Dave Chinner4a8af272013-08-12 20:49:36 +100061 struct dir_context *ctx)
62{
63 int i; /* shortform entry number */
Dave Chinner53f82db2014-06-06 15:20:32 +100064 struct xfs_inode *dp = args->dp; /* incore directory inode */
Dave Chinner4a8af272013-08-12 20:49:36 +100065 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;
Dave Chinner53f82db2014-06-06 15:20:32 +100071 struct xfs_da_geometry *geo = args->geo;
Dave Chinner4a8af272013-08-12 20:49:36 +100072
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)) {
Dave Chinner53f82db2014-06-06 15:20:32 +100078 ASSERT(XFS_FORCED_SHUTDOWN(dp->i_mount));
Dave Chinner24513372014-06-25 14:58:08 +100079 return -EIO;
Dave Chinner4a8af272013-08-12 20:49:36 +100080 }
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 */
Dave Chinner7dda6e82014-06-06 15:11:18 +100092 if (xfs_dir2_dataptr_to_db(geo, ctx->pos) > geo->datablk)
Dave Chinner4a8af272013-08-12 20:49:36 +100093 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
Dave Chinner7dda6e82014-06-06 15:11:18 +100099 * geo->datablk
Dave Chinner4a8af272013-08-12 20:49:36 +1000100 */
Dave Chinner7dda6e82014-06-06 15:11:18 +1000101 dot_offset = xfs_dir2_db_off_to_dataptr(geo, geo->datablk,
Dave Chinner1c9a5b22013-10-30 09:15:02 +1100102 dp->d_ops->data_dot_offset);
Dave Chinner7dda6e82014-06-06 15:11:18 +1000103 dotdot_offset = xfs_dir2_db_off_to_dataptr(geo, geo->datablk,
Dave Chinner1c9a5b22013-10-30 09:15:02 +1100104 dp->d_ops->data_dotdot_offset);
Dave Chinner4a8af272013-08-12 20:49:36 +1000105
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) {
Dave Chinner47401752013-10-29 22:11:47 +1100119 ino = dp->d_ops->sf_get_parent_ino(sfp);
Dave Chinner4a8af272013-08-12 20:49:36 +1000120 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++) {
Dave Chinner0cb97762013-08-12 20:50:09 +1000130 __uint8_t filetype;
131
Dave Chinner7dda6e82014-06-06 15:11:18 +1000132 off = xfs_dir2_db_off_to_dataptr(geo, geo->datablk,
Dave Chinner4a8af272013-08-12 20:49:36 +1000133 xfs_dir2_sf_get_offset(sfep));
134
135 if (ctx->pos > off) {
Dave Chinner32c54832013-10-29 22:11:46 +1100136 sfep = dp->d_ops->sf_nextentry(sfp, sfep);
Dave Chinner4a8af272013-08-12 20:49:36 +1000137 continue;
138 }
139
Dave Chinner47401752013-10-29 22:11:47 +1100140 ino = dp->d_ops->sf_get_ino(sfp, sfep);
141 filetype = dp->d_ops->sf_get_ftype(sfep);
Dave Chinner4a8af272013-08-12 20:49:36 +1000142 ctx->pos = off & 0x7fffffff;
Dave Chinner0cb97762013-08-12 20:50:09 +1000143 if (!dir_emit(ctx, (char *)sfep->name, sfep->namelen, ino,
Dave Chinner53f82db2014-06-06 15:20:32 +1000144 xfs_dir3_get_dtype(dp->i_mount, filetype)))
Dave Chinner4a8af272013-08-12 20:49:36 +1000145 return 0;
Dave Chinner32c54832013-10-29 22:11:46 +1100146 sfep = dp->d_ops->sf_nextentry(sfp, sfep);
Dave Chinner4a8af272013-08-12 20:49:36 +1000147 }
148
Dave Chinner7dda6e82014-06-06 15:11:18 +1000149 ctx->pos = xfs_dir2_db_off_to_dataptr(geo, geo->datablk + 1, 0) &
Dave Chinner53f82db2014-06-06 15:20:32 +1000150 0x7fffffff;
Dave Chinner4a8af272013-08-12 20:49:36 +1000151 return 0;
152}
153
154/*
155 * Readdir for block directories.
156 */
157STATIC int
158xfs_dir2_block_getdents(
Dave Chinner53f82db2014-06-06 15:20:32 +1000159 struct xfs_da_args *args,
Dave Chinner4a8af272013-08-12 20:49:36 +1000160 struct dir_context *ctx)
161{
Dave Chinner53f82db2014-06-06 15:20:32 +1000162 struct xfs_inode *dp = args->dp; /* incore directory inode */
Dave Chinner4a8af272013-08-12 20:49:36 +1000163 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 */
Dave Chinner4a8af272013-08-12 20:49:36 +1000170 char *ptr; /* current data entry */
171 int wantoff; /* starting block offset */
172 xfs_off_t cook;
Dave Chinner53f82db2014-06-06 15:20:32 +1000173 struct xfs_da_geometry *geo = args->geo;
Dave Chinnerdbad7c92015-08-19 10:33:00 +1000174 int lock_mode;
Dave Chinner4a8af272013-08-12 20:49:36 +1000175
Dave Chinner4a8af272013-08-12 20:49:36 +1000176 /*
177 * If the block number in the offset is out of range, we're done.
178 */
Dave Chinner7dda6e82014-06-06 15:11:18 +1000179 if (xfs_dir2_dataptr_to_db(geo, ctx->pos) > geo->datablk)
Dave Chinner4a8af272013-08-12 20:49:36 +1000180 return 0;
181
Dave Chinnerdbad7c92015-08-19 10:33:00 +1000182 lock_mode = xfs_ilock_data_map_shared(dp);
Dave Chinner4a8af272013-08-12 20:49:36 +1000183 error = xfs_dir3_block_read(NULL, dp, &bp);
Dave Chinnerdbad7c92015-08-19 10:33:00 +1000184 xfs_iunlock(dp, lock_mode);
Dave Chinner4a8af272013-08-12 20:49:36 +1000185 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 */
Dave Chinner30028032014-06-06 15:08:18 +1000192 wantoff = xfs_dir2_dataptr_to_off(geo, ctx->pos);
Dave Chinner4a8af272013-08-12 20:49:36 +1000193 hdr = bp->b_addr;
194 xfs_dir3_data_check(dp, bp);
195 /*
196 * Set up values for the loop.
197 */
Dave Chinner8f661932014-06-06 15:15:59 +1000198 btp = xfs_dir2_block_tail_p(geo, hdr);
Dave Chinner2ca98772013-10-29 22:11:49 +1100199 ptr = (char *)dp->d_ops->data_entry_p(hdr);
Dave Chinner4a8af272013-08-12 20:49:36 +1000200 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) {
Dave Chinner0cb97762013-08-12 20:50:09 +1000207 __uint8_t filetype;
208
Dave Chinner4a8af272013-08-12 20:49:36 +1000209 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 */
Dave Chinner9d23fc82013-10-29 22:11:48 +1100223 ptr += dp->d_ops->data_entsize(dep->namelen);
Dave Chinner4a8af272013-08-12 20:49:36 +1000224 /*
225 * The entry is before the desired starting point, skip it.
226 */
227 if ((char *)dep - (char *)hdr < wantoff)
228 continue;
229
Dave Chinner7dda6e82014-06-06 15:11:18 +1000230 cook = xfs_dir2_db_off_to_dataptr(geo, geo->datablk,
Dave Chinner4a8af272013-08-12 20:49:36 +1000231 (char *)dep - (char *)hdr);
232
233 ctx->pos = cook & 0x7fffffff;
Dave Chinner9d23fc82013-10-29 22:11:48 +1100234 filetype = dp->d_ops->data_get_ftype(dep);
Dave Chinner4a8af272013-08-12 20:49:36 +1000235 /*
236 * If it didn't fit, set the final offset to here & return.
237 */
238 if (!dir_emit(ctx, (char *)dep->name, dep->namelen,
Dave Chinner0cb97762013-08-12 20:50:09 +1000239 be64_to_cpu(dep->inumber),
Dave Chinner53f82db2014-06-06 15:20:32 +1000240 xfs_dir3_get_dtype(dp->i_mount, filetype))) {
Dave Chinner4a8af272013-08-12 20:49:36 +1000241 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 */
Dave Chinner7dda6e82014-06-06 15:11:18 +1000250 ctx->pos = xfs_dir2_db_off_to_dataptr(geo, geo->datablk + 1, 0) &
Dave Chinner53f82db2014-06-06 15:20:32 +1000251 0x7fffffff;
Dave Chinner4a8af272013-08-12 20:49:36 +1000252 xfs_trans_brelse(NULL, bp);
253 return 0;
254}
255
256struct 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
270STATIC int
271xfs_dir2_leaf_readbuf(
Dave Chinner53f82db2014-06-06 15:20:32 +1000272 struct xfs_da_args *args,
Dave Chinner4a8af272013-08-12 20:49:36 +1000273 size_t bufsize,
274 struct xfs_dir2_leaf_map_info *mip,
275 xfs_dir2_off_t *curoff,
Dave Chinner9f541802016-05-19 00:17:26 +1000276 struct xfs_buf **bpp,
277 bool trim_map)
Dave Chinner4a8af272013-08-12 20:49:36 +1000278{
Dave Chinner53f82db2014-06-06 15:20:32 +1000279 struct xfs_inode *dp = args->dp;
Dave Chinner9f541802016-05-19 00:17:26 +1000280 struct xfs_buf *bp = NULL;
Dave Chinner4a8af272013-08-12 20:49:36 +1000281 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;
Dave Chinner53f82db2014-06-06 15:20:32 +1000287 struct xfs_da_geometry *geo = args->geo;
Dave Chinner4a8af272013-08-12 20:49:36 +1000288
289 /*
Dave Chinner9f541802016-05-19 00:17:26 +1000290 * 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.
Dave Chinner4a8af272013-08-12 20:49:36 +1000292 */
Dave Chinner9f541802016-05-19 00:17:26 +1000293 if (trim_map) {
Dave Chinnerd6cf1302014-06-06 15:14:11 +1000294 mip->map_blocks -= geo->fsbcount;
Dave Chinner4a8af272013-08-12 20:49:36 +1000295 /*
296 * Loop to get rid of the extents for the
297 * directory block.
298 */
Dave Chinnerd6cf1302014-06-06 15:14:11 +1000299 for (i = geo->fsbcount; i > 0; ) {
Dave Chinner4a8af272013-08-12 20:49:36 +1000300 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 */
Dave Chinner53f82db2014-06-06 15:20:32 +1000318 mip->ra_want = howmany(bufsize + geo->blksize, (1 << geo->fsblog)) - 1;
Dave Chinner4a8af272013-08-12 20:49:36 +1000319 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 &&
Dave Chinner30028032014-06-06 15:08:18 +1000326 mip->map_off < xfs_dir2_byte_to_da(geo, XFS_DIR2_LEAF_OFFSET)) {
Dave Chinner4a8af272013-08-12 20:49:36 +1000327 /*
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,
Dave Chinner30028032014-06-06 15:08:18 +1000333 xfs_dir2_byte_to_da(geo, XFS_DIR2_LEAF_OFFSET) -
Dave Chinner4a8af272013-08-12 20:49:36 +1000334 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
Dave Chinner30028032014-06-06 15:08:18 +1000354 mip->map_off = xfs_dir2_byte_to_da(geo,
Dave Chinner4a8af272013-08-12 20:49:36 +1000355 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) {
Dave Chinner30028032014-06-06 15:08:18 +1000380 *curoff = xfs_dir2_da_to_byte(geo, mip->map_off);
Dave Chinner4a8af272013-08-12 20:49:36 +1000381 goto out;
382 }
383
384 /*
385 * Read the directory block starting at the first mapping.
386 */
Dave Chinner30028032014-06-06 15:08:18 +1000387 mip->curdb = xfs_dir2_da_to_db(geo, map->br_startoff);
Dave Chinner4a8af272013-08-12 20:49:36 +1000388 error = xfs_dir3_data_read(NULL, dp, map->br_startoff,
Dave Chinnerd6cf1302014-06-06 15:14:11 +1000389 map->br_blockcount >= geo->fsbcount ?
Dave Chinner53f82db2014-06-06 15:20:32 +1000390 XFS_FSB_TO_DADDR(dp->i_mount, map->br_startblock) :
391 -1, &bp);
Dave Chinner4a8af272013-08-12 20:49:36 +1000392 /*
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)
Dave Chinnerd6cf1302014-06-06 15:14:11 +1000403 mip->ra_current -= geo->fsbcount;
Dave Chinner4a8af272013-08-12 20:49:36 +1000404
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;
Dave Chinnerd6cf1302014-06-06 15:14:11 +1000411 i += geo->fsbcount) {
Dave Chinner4a8af272013-08-12 20:49:36 +1000412 ASSERT(mip->ra_index < mip->map_valid);
413 /*
414 * Read-ahead a contiguous directory block.
415 */
416 if (i > mip->ra_current &&
Dave Chinnerd6cf1302014-06-06 15:14:11 +1000417 map[mip->ra_index].br_blockcount >= geo->fsbcount) {
Eric Sandeen9df2dd02014-04-14 19:01:59 +1000418 xfs_dir3_data_readahead(dp,
Dave Chinner4a8af272013-08-12 20:49:36 +1000419 map[mip->ra_index].br_startoff + mip->ra_offset,
Dave Chinner53f82db2014-06-06 15:20:32 +1000420 XFS_FSB_TO_DADDR(dp->i_mount,
Dave Chinner4a8af272013-08-12 20:49:36 +1000421 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) {
Eric Sandeen9df2dd02014-04-14 19:01:59 +1000431 xfs_dir3_data_readahead(dp,
Dave Chinner4a8af272013-08-12 20:49:36 +1000432 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 */
Dave Chinnerd6cf1302014-06-06 15:14:11 +1000440 for (j = 0; j < geo->fsbcount; j += length ) {
Dave Chinner4a8af272013-08-12 20:49:36 +1000441 /*
442 * The rest of this extent but not more than a dir
443 * block.
444 */
Dave Chinnerd6cf1302014-06-06 15:14:11 +1000445 length = min_t(int, geo->fsbcount,
Dave Chinner4a8af272013-08-12 20:49:36 +1000446 map[mip->ra_index].br_blockcount -
447 mip->ra_offset);
Dave Chinner4a8af272013-08-12 20:49:36 +1000448 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
461out:
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 */
470STATIC int
471xfs_dir2_leaf_getdents(
Dave Chinner53f82db2014-06-06 15:20:32 +1000472 struct xfs_da_args *args,
Dave Chinner4a8af272013-08-12 20:49:36 +1000473 struct dir_context *ctx,
474 size_t bufsize)
475{
Dave Chinner53f82db2014-06-06 15:20:32 +1000476 struct xfs_inode *dp = args->dp;
Dave Chinner4a8af272013-08-12 20:49:36 +1000477 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 */
Dave Chinner4a8af272013-08-12 20:49:36 +1000483 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;
Dave Chinner53f82db2014-06-06 15:20:32 +1000488 struct xfs_da_geometry *geo = args->geo;
Dave Chinner4a8af272013-08-12 20:49:36 +1000489
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
Dave Chinner4a8af272013-08-12 20:49:36 +1000497 /*
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 */
Dave Chinner53f82db2014-06-06 15:20:32 +1000502 length = howmany(bufsize + geo->blksize, (1 << geo->fsblog));
Dave Chinner4a8af272013-08-12 20:49:36 +1000503 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 */
Eric Sandeen25994052014-04-14 19:02:30 +1000512 curoff = xfs_dir2_dataptr_to_byte(ctx->pos);
Dave Chinner4a8af272013-08-12 20:49:36 +1000513
514 /*
515 * Force this conversion through db so we truncate the offset
516 * down to get the start of the data block.
517 */
Dave Chinner30028032014-06-06 15:08:18 +1000518 map_info->map_off = xfs_dir2_db_to_da(geo,
519 xfs_dir2_byte_to_db(geo, curoff));
Dave Chinner4a8af272013-08-12 20:49:36 +1000520
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) {
Dave Chinner0cb97762013-08-12 20:50:09 +1000526 __uint8_t filetype;
527
Dave Chinner4a8af272013-08-12 20:49:36 +1000528 /*
529 * If we have no buffer, or we're off the end of the
530 * current buffer, need to get another one.
531 */
Dave Chinner8f661932014-06-06 15:15:59 +1000532 if (!bp || ptr >= (char *)bp->b_addr + geo->blksize) {
Dave Chinnerdbad7c92015-08-19 10:33:00 +1000533 int lock_mode;
Dave Chinner9f541802016-05-19 00:17:26 +1000534 bool trim_map = false;
535
536 if (bp) {
537 xfs_trans_brelse(NULL, bp);
538 bp = NULL;
539 trim_map = true;
540 }
Dave Chinner4a8af272013-08-12 20:49:36 +1000541
Dave Chinnerdbad7c92015-08-19 10:33:00 +1000542 lock_mode = xfs_ilock_data_map_shared(dp);
Dave Chinner53f82db2014-06-06 15:20:32 +1000543 error = xfs_dir2_leaf_readbuf(args, bufsize, map_info,
Dave Chinner9f541802016-05-19 00:17:26 +1000544 &curoff, &bp, trim_map);
Dave Chinnerdbad7c92015-08-19 10:33:00 +1000545 xfs_iunlock(dp, lock_mode);
Dave Chinner4a8af272013-08-12 20:49:36 +1000546 if (error || !map_info->map_valid)
547 break;
548
549 /*
550 * Having done a read, we need to set a new offset.
551 */
Dave Chinner53f82db2014-06-06 15:20:32 +1000552 newoff = xfs_dir2_db_off_to_byte(geo,
Dave Chinner9b3b5522014-06-06 15:06:53 +1000553 map_info->curdb, 0);
Dave Chinner4a8af272013-08-12 20:49:36 +1000554 /*
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)
Dave Chinner30028032014-06-06 15:08:18 +1000563 ASSERT(xfs_dir2_byte_to_db(geo, curoff) ==
Dave Chinner4a8af272013-08-12 20:49:36 +1000564 map_info->curdb);
565 hdr = bp->b_addr;
566 xfs_dir3_data_check(dp, bp);
567 /*
568 * Find our position in the block.
569 */
Dave Chinner2ca98772013-10-29 22:11:49 +1100570 ptr = (char *)dp->d_ops->data_entry_p(hdr);
Dave Chinner53f82db2014-06-06 15:20:32 +1000571 byteoff = xfs_dir2_byte_to_off(geo, curoff);
Dave Chinner4a8af272013-08-12 20:49:36 +1000572 /*
573 * Skip past the header.
574 */
575 if (byteoff == 0)
Dave Chinner1c9a5b22013-10-30 09:15:02 +1100576 curoff += dp->d_ops->data_entry_offset;
Dave Chinner4a8af272013-08-12 20:49:36 +1000577 /*
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 =
Dave Chinner9d23fc82013-10-29 22:11:48 +1100593 dp->d_ops->data_entsize(dep->namelen);
Dave Chinner4a8af272013-08-12 20:49:36 +1000594 ptr += length;
595 }
596 /*
597 * Now set our real offset.
598 */
599 curoff =
Dave Chinner30028032014-06-06 15:08:18 +1000600 xfs_dir2_db_off_to_byte(geo,
601 xfs_dir2_byte_to_db(geo, curoff),
Dave Chinner4a8af272013-08-12 20:49:36 +1000602 (char *)ptr - (char *)hdr);
Dave Chinner8f661932014-06-06 15:15:59 +1000603 if (ptr >= (char *)hdr + geo->blksize) {
Dave Chinner4a8af272013-08-12 20:49:36 +1000604 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;
Dave Chinner9d23fc82013-10-29 22:11:48 +1100624 length = dp->d_ops->data_entsize(dep->namelen);
625 filetype = dp->d_ops->data_get_ftype(dep);
Dave Chinner4a8af272013-08-12 20:49:36 +1000626
Eric Sandeen25994052014-04-14 19:02:30 +1000627 ctx->pos = xfs_dir2_byte_to_dataptr(curoff) & 0x7fffffff;
Dave Chinner4a8af272013-08-12 20:49:36 +1000628 if (!dir_emit(ctx, (char *)dep->name, dep->namelen,
Dave Chinner0cb97762013-08-12 20:50:09 +1000629 be64_to_cpu(dep->inumber),
Dave Chinner53f82db2014-06-06 15:20:32 +1000630 xfs_dir3_get_dtype(dp->i_mount, filetype)))
Dave Chinner4a8af272013-08-12 20:49:36 +1000631 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 */
Eric Sandeen25994052014-04-14 19:02:30 +1000645 if (curoff > xfs_dir2_dataptr_to_byte(XFS_DIR2_MAX_DATAPTR))
Dave Chinner4a8af272013-08-12 20:49:36 +1000646 ctx->pos = XFS_DIR2_MAX_DATAPTR & 0x7fffffff;
647 else
Eric Sandeen25994052014-04-14 19:02:30 +1000648 ctx->pos = xfs_dir2_byte_to_dataptr(curoff) & 0x7fffffff;
Dave Chinner4a8af272013-08-12 20:49:36 +1000649 kmem_free(map_info);
650 if (bp)
651 xfs_trans_brelse(NULL, bp);
652 return error;
653}
654
655/*
656 * Read a directory.
657 */
658int
659xfs_readdir(
Dave Chinner53f82db2014-06-06 15:20:32 +1000660 struct xfs_inode *dp,
661 struct dir_context *ctx,
662 size_t bufsize)
Dave Chinner4a8af272013-08-12 20:49:36 +1000663{
Dave Chinner35f46c52014-06-10 07:30:36 +1000664 struct xfs_da_args args = { NULL };
Dave Chinner53f82db2014-06-06 15:20:32 +1000665 int rval;
666 int v;
Dave Chinner4a8af272013-08-12 20:49:36 +1000667
668 trace_xfs_readdir(dp);
669
670 if (XFS_FORCED_SHUTDOWN(dp->i_mount))
Dave Chinner24513372014-06-25 14:58:08 +1000671 return -EIO;
Dave Chinner4a8af272013-08-12 20:49:36 +1000672
Dave Chinnerc19b3b052016-02-09 16:54:58 +1100673 ASSERT(S_ISDIR(VFS_I(dp)->i_mode));
Bill O'Donnellff6d6af2015-10-12 18:21:22 +1100674 XFS_STATS_INC(dp->i_mount, xs_dir_getdents);
Dave Chinner4a8af272013-08-12 20:49:36 +1000675
Dave Chinner53f82db2014-06-06 15:20:32 +1000676 args.dp = dp;
677 args.geo = dp->i_mount->m_dir_geo;
678
Dave Chinnerdbad7c92015-08-19 10:33:00 +1000679 xfs_ilock(dp, XFS_IOLOCK_SHARED);
Dave Chinner4a8af272013-08-12 20:49:36 +1000680 if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL)
Dave Chinner53f82db2014-06-06 15:20:32 +1000681 rval = xfs_dir2_sf_getdents(&args, ctx);
682 else if ((rval = xfs_dir2_isblock(&args, &v)))
Dave Chinner4a8af272013-08-12 20:49:36 +1000683 ;
684 else if (v)
Dave Chinner53f82db2014-06-06 15:20:32 +1000685 rval = xfs_dir2_block_getdents(&args, ctx);
Dave Chinner4a8af272013-08-12 20:49:36 +1000686 else
Dave Chinner53f82db2014-06-06 15:20:32 +1000687 rval = xfs_dir2_leaf_getdents(&args, ctx, bufsize);
Dave Chinnerdbad7c92015-08-19 10:33:00 +1000688 xfs_iunlock(dp, XFS_IOLOCK_SHARED);
Ben Myers40194ec2013-12-06 12:30:11 -0800689
Dave Chinner4a8af272013-08-12 20:49:36 +1000690 return rval;
691}