/fs/xfs/xfs_vnodeops.c
C | 2348 lines | 1519 code | 282 blank | 547 comment | 338 complexity | 94f8a60308c5d2a920684c3c4903862e MD5 | raw file
Possible License(s): AGPL-1.0, GPL-2.0, LGPL-2.0
1/*
2 * Copyright (c) 2000-2006 Silicon Graphics, Inc.
3 * All Rights Reserved.
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it would be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
17 */
18
19#include "xfs.h"
20#include "xfs_fs.h"
21#include "xfs_types.h"
22#include "xfs_bit.h"
23#include "xfs_log.h"
24#include "xfs_trans.h"
25#include "xfs_sb.h"
26#include "xfs_ag.h"
27#include "xfs_dir2.h"
28#include "xfs_mount.h"
29#include "xfs_da_btree.h"
30#include "xfs_bmap_btree.h"
31#include "xfs_ialloc_btree.h"
32#include "xfs_dinode.h"
33#include "xfs_inode.h"
34#include "xfs_inode_item.h"
35#include "xfs_itable.h"
36#include "xfs_ialloc.h"
37#include "xfs_alloc.h"
38#include "xfs_bmap.h"
39#include "xfs_acl.h"
40#include "xfs_attr.h"
41#include "xfs_error.h"
42#include "xfs_quota.h"
43#include "xfs_utils.h"
44#include "xfs_rtalloc.h"
45#include "xfs_trans_space.h"
46#include "xfs_log_priv.h"
47#include "xfs_filestream.h"
48#include "xfs_vnodeops.h"
49#include "xfs_trace.h"
50#include "xfs_icache.h"
51
52/*
53 * The maximum pathlen is 1024 bytes. Since the minimum file system
54 * blocksize is 512 bytes, we can get a max of 2 extents back from
55 * bmapi.
56 */
57#define SYMLINK_MAPS 2
58
59STATIC int
60xfs_readlink_bmap(
61 xfs_inode_t *ip,
62 char *link)
63{
64 xfs_mount_t *mp = ip->i_mount;
65 int pathlen = ip->i_d.di_size;
66 int nmaps = SYMLINK_MAPS;
67 xfs_bmbt_irec_t mval[SYMLINK_MAPS];
68 xfs_daddr_t d;
69 int byte_cnt;
70 int n;
71 xfs_buf_t *bp;
72 int error = 0;
73
74 error = xfs_bmapi_read(ip, 0, XFS_B_TO_FSB(mp, pathlen), mval, &nmaps,
75 0);
76 if (error)
77 goto out;
78
79 for (n = 0; n < nmaps; n++) {
80 d = XFS_FSB_TO_DADDR(mp, mval[n].br_startblock);
81 byte_cnt = XFS_FSB_TO_B(mp, mval[n].br_blockcount);
82
83 bp = xfs_buf_read(mp->m_ddev_targp, d, BTOBB(byte_cnt), 0, NULL);
84 if (!bp)
85 return XFS_ERROR(ENOMEM);
86 error = bp->b_error;
87 if (error) {
88 xfs_buf_ioerror_alert(bp, __func__);
89 xfs_buf_relse(bp);
90 goto out;
91 }
92 if (pathlen < byte_cnt)
93 byte_cnt = pathlen;
94 pathlen -= byte_cnt;
95
96 memcpy(link, bp->b_addr, byte_cnt);
97 xfs_buf_relse(bp);
98 }
99
100 link[ip->i_d.di_size] = '\0';
101 error = 0;
102
103 out:
104 return error;
105}
106
107int
108xfs_readlink(
109 xfs_inode_t *ip,
110 char *link)
111{
112 xfs_mount_t *mp = ip->i_mount;
113 xfs_fsize_t pathlen;
114 int error = 0;
115
116 trace_xfs_readlink(ip);
117
118 if (XFS_FORCED_SHUTDOWN(mp))
119 return XFS_ERROR(EIO);
120
121 xfs_ilock(ip, XFS_ILOCK_SHARED);
122
123 pathlen = ip->i_d.di_size;
124 if (!pathlen)
125 goto out;
126
127 if (pathlen < 0 || pathlen > MAXPATHLEN) {
128 xfs_alert(mp, "%s: inode (%llu) bad symlink length (%lld)",
129 __func__, (unsigned long long) ip->i_ino,
130 (long long) pathlen);
131 ASSERT(0);
132 error = XFS_ERROR(EFSCORRUPTED);
133 goto out;
134 }
135
136
137 if (ip->i_df.if_flags & XFS_IFINLINE) {
138 memcpy(link, ip->i_df.if_u1.if_data, pathlen);
139 link[pathlen] = '\0';
140 } else {
141 error = xfs_readlink_bmap(ip, link);
142 }
143
144 out:
145 xfs_iunlock(ip, XFS_ILOCK_SHARED);
146 return error;
147}
148
149/*
150 * This is called by xfs_inactive to free any blocks beyond eof
151 * when the link count isn't zero and by xfs_dm_punch_hole() when
152 * punching a hole to EOF.
153 */
154int
155xfs_free_eofblocks(
156 xfs_mount_t *mp,
157 xfs_inode_t *ip,
158 bool need_iolock)
159{
160 xfs_trans_t *tp;
161 int error;
162 xfs_fileoff_t end_fsb;
163 xfs_fileoff_t last_fsb;
164 xfs_filblks_t map_len;
165 int nimaps;
166 xfs_bmbt_irec_t imap;
167
168 /*
169 * Figure out if there are any blocks beyond the end
170 * of the file. If not, then there is nothing to do.
171 */
172 end_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)XFS_ISIZE(ip));
173 last_fsb = XFS_B_TO_FSB(mp, mp->m_super->s_maxbytes);
174 if (last_fsb <= end_fsb)
175 return 0;
176 map_len = last_fsb - end_fsb;
177
178 nimaps = 1;
179 xfs_ilock(ip, XFS_ILOCK_SHARED);
180 error = xfs_bmapi_read(ip, end_fsb, map_len, &imap, &nimaps, 0);
181 xfs_iunlock(ip, XFS_ILOCK_SHARED);
182
183 if (!error && (nimaps != 0) &&
184 (imap.br_startblock != HOLESTARTBLOCK ||
185 ip->i_delayed_blks)) {
186 /*
187 * Attach the dquots to the inode up front.
188 */
189 error = xfs_qm_dqattach(ip, 0);
190 if (error)
191 return error;
192
193 /*
194 * There are blocks after the end of file.
195 * Free them up now by truncating the file to
196 * its current size.
197 */
198 tp = xfs_trans_alloc(mp, XFS_TRANS_INACTIVE);
199
200 if (need_iolock) {
201 if (!xfs_ilock_nowait(ip, XFS_IOLOCK_EXCL)) {
202 xfs_trans_cancel(tp, 0);
203 return EAGAIN;
204 }
205 }
206
207 error = xfs_trans_reserve(tp, 0,
208 XFS_ITRUNCATE_LOG_RES(mp),
209 0, XFS_TRANS_PERM_LOG_RES,
210 XFS_ITRUNCATE_LOG_COUNT);
211 if (error) {
212 ASSERT(XFS_FORCED_SHUTDOWN(mp));
213 xfs_trans_cancel(tp, 0);
214 if (need_iolock)
215 xfs_iunlock(ip, XFS_IOLOCK_EXCL);
216 return error;
217 }
218
219 xfs_ilock(ip, XFS_ILOCK_EXCL);
220 xfs_trans_ijoin(tp, ip, 0);
221
222 /*
223 * Do not update the on-disk file size. If we update the
224 * on-disk file size and then the system crashes before the
225 * contents of the file are flushed to disk then the files
226 * may be full of holes (ie NULL files bug).
227 */
228 error = xfs_itruncate_extents(&tp, ip, XFS_DATA_FORK,
229 XFS_ISIZE(ip));
230 if (error) {
231 /*
232 * If we get an error at this point we simply don't
233 * bother truncating the file.
234 */
235 xfs_trans_cancel(tp,
236 (XFS_TRANS_RELEASE_LOG_RES |
237 XFS_TRANS_ABORT));
238 } else {
239 error = xfs_trans_commit(tp,
240 XFS_TRANS_RELEASE_LOG_RES);
241 if (!error)
242 xfs_inode_clear_eofblocks_tag(ip);
243 }
244
245 xfs_iunlock(ip, XFS_ILOCK_EXCL);
246 if (need_iolock)
247 xfs_iunlock(ip, XFS_IOLOCK_EXCL);
248 }
249 return error;
250}
251
252/*
253 * Free a symlink that has blocks associated with it.
254 */
255STATIC int
256xfs_inactive_symlink_rmt(
257 xfs_inode_t *ip,
258 xfs_trans_t **tpp)
259{
260 xfs_buf_t *bp;
261 int committed;
262 int done;
263 int error;
264 xfs_fsblock_t first_block;
265 xfs_bmap_free_t free_list;
266 int i;
267 xfs_mount_t *mp;
268 xfs_bmbt_irec_t mval[SYMLINK_MAPS];
269 int nmaps;
270 xfs_trans_t *ntp;
271 int size;
272 xfs_trans_t *tp;
273
274 tp = *tpp;
275 mp = ip->i_mount;
276 ASSERT(ip->i_d.di_size > XFS_IFORK_DSIZE(ip));
277 /*
278 * We're freeing a symlink that has some
279 * blocks allocated to it. Free the
280 * blocks here. We know that we've got
281 * either 1 or 2 extents and that we can
282 * free them all in one bunmapi call.
283 */
284 ASSERT(ip->i_d.di_nextents > 0 && ip->i_d.di_nextents <= 2);
285
286 /*
287 * Lock the inode, fix the size, and join it to the transaction.
288 * Hold it so in the normal path, we still have it locked for
289 * the second transaction. In the error paths we need it
290 * held so the cancel won't rele it, see below.
291 */
292 size = (int)ip->i_d.di_size;
293 ip->i_d.di_size = 0;
294 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
295 /*
296 * Find the block(s) so we can inval and unmap them.
297 */
298 done = 0;
299 xfs_bmap_init(&free_list, &first_block);
300 nmaps = ARRAY_SIZE(mval);
301 error = xfs_bmapi_read(ip, 0, XFS_B_TO_FSB(mp, size),
302 mval, &nmaps, 0);
303 if (error)
304 goto error0;
305 /*
306 * Invalidate the block(s).
307 */
308 for (i = 0; i < nmaps; i++) {
309 bp = xfs_trans_get_buf(tp, mp->m_ddev_targp,
310 XFS_FSB_TO_DADDR(mp, mval[i].br_startblock),
311 XFS_FSB_TO_BB(mp, mval[i].br_blockcount), 0);
312 if (!bp) {
313 error = ENOMEM;
314 goto error1;
315 }
316 xfs_trans_binval(tp, bp);
317 }
318 /*
319 * Unmap the dead block(s) to the free_list.
320 */
321 if ((error = xfs_bunmapi(tp, ip, 0, size, XFS_BMAPI_METADATA, nmaps,
322 &first_block, &free_list, &done)))
323 goto error1;
324 ASSERT(done);
325 /*
326 * Commit the first transaction. This logs the EFI and the inode.
327 */
328 if ((error = xfs_bmap_finish(&tp, &free_list, &committed)))
329 goto error1;
330 /*
331 * The transaction must have been committed, since there were
332 * actually extents freed by xfs_bunmapi. See xfs_bmap_finish.
333 * The new tp has the extent freeing and EFDs.
334 */
335 ASSERT(committed);
336 /*
337 * The first xact was committed, so add the inode to the new one.
338 * Mark it dirty so it will be logged and moved forward in the log as
339 * part of every commit.
340 */
341 xfs_trans_ijoin(tp, ip, 0);
342 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
343 /*
344 * Get a new, empty transaction to return to our caller.
345 */
346 ntp = xfs_trans_dup(tp);
347 /*
348 * Commit the transaction containing extent freeing and EFDs.
349 * If we get an error on the commit here or on the reserve below,
350 * we need to unlock the inode since the new transaction doesn't
351 * have the inode attached.
352 */
353 error = xfs_trans_commit(tp, 0);
354 tp = ntp;
355 if (error) {
356 ASSERT(XFS_FORCED_SHUTDOWN(mp));
357 goto error0;
358 }
359 /*
360 * transaction commit worked ok so we can drop the extra ticket
361 * reference that we gained in xfs_trans_dup()
362 */
363 xfs_log_ticket_put(tp->t_ticket);
364
365 /*
366 * Remove the memory for extent descriptions (just bookkeeping).
367 */
368 if (ip->i_df.if_bytes)
369 xfs_idata_realloc(ip, -ip->i_df.if_bytes, XFS_DATA_FORK);
370 ASSERT(ip->i_df.if_bytes == 0);
371 /*
372 * Put an itruncate log reservation in the new transaction
373 * for our caller.
374 */
375 if ((error = xfs_trans_reserve(tp, 0, XFS_ITRUNCATE_LOG_RES(mp), 0,
376 XFS_TRANS_PERM_LOG_RES, XFS_ITRUNCATE_LOG_COUNT))) {
377 ASSERT(XFS_FORCED_SHUTDOWN(mp));
378 goto error0;
379 }
380
381 xfs_trans_ijoin(tp, ip, 0);
382 *tpp = tp;
383 return 0;
384
385 error1:
386 xfs_bmap_cancel(&free_list);
387 error0:
388 return error;
389}
390
391int
392xfs_release(
393 xfs_inode_t *ip)
394{
395 xfs_mount_t *mp = ip->i_mount;
396 int error;
397
398 if (!S_ISREG(ip->i_d.di_mode) || (ip->i_d.di_mode == 0))
399 return 0;
400
401 /* If this is a read-only mount, don't do this (would generate I/O) */
402 if (mp->m_flags & XFS_MOUNT_RDONLY)
403 return 0;
404
405 if (!XFS_FORCED_SHUTDOWN(mp)) {
406 int truncated;
407
408 /*
409 * If we are using filestreams, and we have an unlinked
410 * file that we are processing the last close on, then nothing
411 * will be able to reopen and write to this file. Purge this
412 * inode from the filestreams cache so that it doesn't delay
413 * teardown of the inode.
414 */
415 if ((ip->i_d.di_nlink == 0) && xfs_inode_is_filestream(ip))
416 xfs_filestream_deassociate(ip);
417
418 /*
419 * If we previously truncated this file and removed old data
420 * in the process, we want to initiate "early" writeout on
421 * the last close. This is an attempt to combat the notorious
422 * NULL files problem which is particularly noticeable from a
423 * truncate down, buffered (re-)write (delalloc), followed by
424 * a crash. What we are effectively doing here is
425 * significantly reducing the time window where we'd otherwise
426 * be exposed to that problem.
427 */
428 truncated = xfs_iflags_test_and_clear(ip, XFS_ITRUNCATED);
429 if (truncated) {
430 xfs_iflags_clear(ip, XFS_IDIRTY_RELEASE);
431 if (VN_DIRTY(VFS_I(ip)) && ip->i_delayed_blks > 0) {
432 error = -filemap_flush(VFS_I(ip)->i_mapping);
433 if (error)
434 return error;
435 }
436 }
437 }
438
439 if (ip->i_d.di_nlink == 0)
440 return 0;
441
442 if (xfs_can_free_eofblocks(ip, false)) {
443
444 /*
445 * If we can't get the iolock just skip truncating the blocks
446 * past EOF because we could deadlock with the mmap_sem
447 * otherwise. We'll get another chance to drop them once the
448 * last reference to the inode is dropped, so we'll never leak
449 * blocks permanently.
450 *
451 * Further, check if the inode is being opened, written and
452 * closed frequently and we have delayed allocation blocks
453 * outstanding (e.g. streaming writes from the NFS server),
454 * truncating the blocks past EOF will cause fragmentation to
455 * occur.
456 *
457 * In this case don't do the truncation, either, but we have to
458 * be careful how we detect this case. Blocks beyond EOF show
459 * up as i_delayed_blks even when the inode is clean, so we
460 * need to truncate them away first before checking for a dirty
461 * release. Hence on the first dirty close we will still remove
462 * the speculative allocation, but after that we will leave it
463 * in place.
464 */
465 if (xfs_iflags_test(ip, XFS_IDIRTY_RELEASE))
466 return 0;
467
468 error = xfs_free_eofblocks(mp, ip, true);
469 if (error && error != EAGAIN)
470 return error;
471
472 /* delalloc blocks after truncation means it really is dirty */
473 if (ip->i_delayed_blks)
474 xfs_iflags_set(ip, XFS_IDIRTY_RELEASE);
475 }
476 return 0;
477}
478
479/*
480 * xfs_inactive
481 *
482 * This is called when the vnode reference count for the vnode
483 * goes to zero. If the file has been unlinked, then it must
484 * now be truncated. Also, we clear all of the read-ahead state
485 * kept for the inode here since the file is now closed.
486 */
487int
488xfs_inactive(
489 xfs_inode_t *ip)
490{
491 xfs_bmap_free_t free_list;
492 xfs_fsblock_t first_block;
493 int committed;
494 xfs_trans_t *tp;
495 xfs_mount_t *mp;
496 int error;
497 int truncate = 0;
498
499 /*
500 * If the inode is already free, then there can be nothing
501 * to clean up here.
502 */
503 if (ip->i_d.di_mode == 0 || is_bad_inode(VFS_I(ip))) {
504 ASSERT(ip->i_df.if_real_bytes == 0);
505 ASSERT(ip->i_df.if_broot_bytes == 0);
506 return VN_INACTIVE_CACHE;
507 }
508
509 mp = ip->i_mount;
510
511 error = 0;
512
513 /* If this is a read-only mount, don't do this (would generate I/O) */
514 if (mp->m_flags & XFS_MOUNT_RDONLY)
515 goto out;
516
517 if (ip->i_d.di_nlink != 0) {
518 /*
519 * force is true because we are evicting an inode from the
520 * cache. Post-eof blocks must be freed, lest we end up with
521 * broken free space accounting.
522 */
523 if (xfs_can_free_eofblocks(ip, true)) {
524 error = xfs_free_eofblocks(mp, ip, false);
525 if (error)
526 return VN_INACTIVE_CACHE;
527 }
528 goto out;
529 }
530
531 if (S_ISREG(ip->i_d.di_mode) &&
532 (ip->i_d.di_size != 0 || XFS_ISIZE(ip) != 0 ||
533 ip->i_d.di_nextents > 0 || ip->i_delayed_blks > 0))
534 truncate = 1;
535
536 error = xfs_qm_dqattach(ip, 0);
537 if (error)
538 return VN_INACTIVE_CACHE;
539
540 tp = xfs_trans_alloc(mp, XFS_TRANS_INACTIVE);
541 error = xfs_trans_reserve(tp, 0,
542 (truncate || S_ISLNK(ip->i_d.di_mode)) ?
543 XFS_ITRUNCATE_LOG_RES(mp) :
544 XFS_IFREE_LOG_RES(mp),
545 0,
546 XFS_TRANS_PERM_LOG_RES,
547 XFS_ITRUNCATE_LOG_COUNT);
548 if (error) {
549 ASSERT(XFS_FORCED_SHUTDOWN(mp));
550 xfs_trans_cancel(tp, 0);
551 return VN_INACTIVE_CACHE;
552 }
553
554 xfs_ilock(ip, XFS_ILOCK_EXCL);
555 xfs_trans_ijoin(tp, ip, 0);
556
557 if (S_ISLNK(ip->i_d.di_mode)) {
558 /*
559 * Zero length symlinks _can_ exist.
560 */
561 if (ip->i_d.di_size > XFS_IFORK_DSIZE(ip)) {
562 error = xfs_inactive_symlink_rmt(ip, &tp);
563 if (error)
564 goto out_cancel;
565 } else if (ip->i_df.if_bytes > 0) {
566 xfs_idata_realloc(ip, -(ip->i_df.if_bytes),
567 XFS_DATA_FORK);
568 ASSERT(ip->i_df.if_bytes == 0);
569 }
570 } else if (truncate) {
571 ip->i_d.di_size = 0;
572 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
573
574 error = xfs_itruncate_extents(&tp, ip, XFS_DATA_FORK, 0);
575 if (error)
576 goto out_cancel;
577
578 ASSERT(ip->i_d.di_nextents == 0);
579 }
580
581 /*
582 * If there are attributes associated with the file then blow them away
583 * now. The code calls a routine that recursively deconstructs the
584 * attribute fork. We need to just commit the current transaction
585 * because we can't use it for xfs_attr_inactive().
586 */
587 if (ip->i_d.di_anextents > 0) {
588 ASSERT(ip->i_d.di_forkoff != 0);
589
590 error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
591 if (error)
592 goto out_unlock;
593
594 xfs_iunlock(ip, XFS_ILOCK_EXCL);
595
596 error = xfs_attr_inactive(ip);
597 if (error)
598 goto out;
599
600 tp = xfs_trans_alloc(mp, XFS_TRANS_INACTIVE);
601 error = xfs_trans_reserve(tp, 0,
602 XFS_IFREE_LOG_RES(mp),
603 0, XFS_TRANS_PERM_LOG_RES,
604 XFS_INACTIVE_LOG_COUNT);
605 if (error) {
606 xfs_trans_cancel(tp, 0);
607 goto out;
608 }
609
610 xfs_ilock(ip, XFS_ILOCK_EXCL);
611 xfs_trans_ijoin(tp, ip, 0);
612 }
613
614 if (ip->i_afp)
615 xfs_idestroy_fork(ip, XFS_ATTR_FORK);
616
617 ASSERT(ip->i_d.di_anextents == 0);
618
619 /*
620 * Free the inode.
621 */
622 xfs_bmap_init(&free_list, &first_block);
623 error = xfs_ifree(tp, ip, &free_list);
624 if (error) {
625 /*
626 * If we fail to free the inode, shut down. The cancel
627 * might do that, we need to make sure. Otherwise the
628 * inode might be lost for a long time or forever.
629 */
630 if (!XFS_FORCED_SHUTDOWN(mp)) {
631 xfs_notice(mp, "%s: xfs_ifree returned error %d",
632 __func__, error);
633 xfs_force_shutdown(mp, SHUTDOWN_META_IO_ERROR);
634 }
635 xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES|XFS_TRANS_ABORT);
636 } else {
637 /*
638 * Credit the quota account(s). The inode is gone.
639 */
640 xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_ICOUNT, -1);
641
642 /*
643 * Just ignore errors at this point. There is nothing we can
644 * do except to try to keep going. Make sure it's not a silent
645 * error.
646 */
647 error = xfs_bmap_finish(&tp, &free_list, &committed);
648 if (error)
649 xfs_notice(mp, "%s: xfs_bmap_finish returned error %d",
650 __func__, error);
651 error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
652 if (error)
653 xfs_notice(mp, "%s: xfs_trans_commit returned error %d",
654 __func__, error);
655 }
656
657 /*
658 * Release the dquots held by inode, if any.
659 */
660 xfs_qm_dqdetach(ip);
661out_unlock:
662 xfs_iunlock(ip, XFS_ILOCK_EXCL);
663out:
664 return VN_INACTIVE_CACHE;
665out_cancel:
666 xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
667 goto out_unlock;
668}
669
670/*
671 * Lookups up an inode from "name". If ci_name is not NULL, then a CI match
672 * is allowed, otherwise it has to be an exact match. If a CI match is found,
673 * ci_name->name will point to a the actual name (caller must free) or
674 * will be set to NULL if an exact match is found.
675 */
676int
677xfs_lookup(
678 xfs_inode_t *dp,
679 struct xfs_name *name,
680 xfs_inode_t **ipp,
681 struct xfs_name *ci_name)
682{
683 xfs_ino_t inum;
684 int error;
685 uint lock_mode;
686
687 trace_xfs_lookup(dp, name);
688
689 if (XFS_FORCED_SHUTDOWN(dp->i_mount))
690 return XFS_ERROR(EIO);
691
692 lock_mode = xfs_ilock_map_shared(dp);
693 error = xfs_dir_lookup(NULL, dp, name, &inum, ci_name);
694 xfs_iunlock_map_shared(dp, lock_mode);
695
696 if (error)
697 goto out;
698
699 error = xfs_iget(dp->i_mount, NULL, inum, 0, 0, ipp);
700 if (error)
701 goto out_free_name;
702
703 return 0;
704
705out_free_name:
706 if (ci_name)
707 kmem_free(ci_name->name);
708out:
709 *ipp = NULL;
710 return error;
711}
712
713int
714xfs_create(
715 xfs_inode_t *dp,
716 struct xfs_name *name,
717 umode_t mode,
718 xfs_dev_t rdev,
719 xfs_inode_t **ipp)
720{
721 int is_dir = S_ISDIR(mode);
722 struct xfs_mount *mp = dp->i_mount;
723 struct xfs_inode *ip = NULL;
724 struct xfs_trans *tp = NULL;
725 int error;
726 xfs_bmap_free_t free_list;
727 xfs_fsblock_t first_block;
728 boolean_t unlock_dp_on_error = B_FALSE;
729 uint cancel_flags;
730 int committed;
731 prid_t prid;
732 struct xfs_dquot *udqp = NULL;
733 struct xfs_dquot *gdqp = NULL;
734 uint resblks;
735 uint log_res;
736 uint log_count;
737
738 trace_xfs_create(dp, name);
739
740 if (XFS_FORCED_SHUTDOWN(mp))
741 return XFS_ERROR(EIO);
742
743 if (dp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT)
744 prid = xfs_get_projid(dp);
745 else
746 prid = XFS_PROJID_DEFAULT;
747
748 /*
749 * Make sure that we have allocated dquot(s) on disk.
750 */
751 error = xfs_qm_vop_dqalloc(dp, current_fsuid(), current_fsgid(), prid,
752 XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT, &udqp, &gdqp);
753 if (error)
754 return error;
755
756 if (is_dir) {
757 rdev = 0;
758 resblks = XFS_MKDIR_SPACE_RES(mp, name->len);
759 log_res = XFS_MKDIR_LOG_RES(mp);
760 log_count = XFS_MKDIR_LOG_COUNT;
761 tp = xfs_trans_alloc(mp, XFS_TRANS_MKDIR);
762 } else {
763 resblks = XFS_CREATE_SPACE_RES(mp, name->len);
764 log_res = XFS_CREATE_LOG_RES(mp);
765 log_count = XFS_CREATE_LOG_COUNT;
766 tp = xfs_trans_alloc(mp, XFS_TRANS_CREATE);
767 }
768
769 cancel_flags = XFS_TRANS_RELEASE_LOG_RES;
770
771 /*
772 * Initially assume that the file does not exist and
773 * reserve the resources for that case. If that is not
774 * the case we'll drop the one we have and get a more
775 * appropriate transaction later.
776 */
777 error = xfs_trans_reserve(tp, resblks, log_res, 0,
778 XFS_TRANS_PERM_LOG_RES, log_count);
779 if (error == ENOSPC) {
780 /* flush outstanding delalloc blocks and retry */
781 xfs_flush_inodes(mp);
782 error = xfs_trans_reserve(tp, resblks, log_res, 0,
783 XFS_TRANS_PERM_LOG_RES, log_count);
784 }
785 if (error == ENOSPC) {
786 /* No space at all so try a "no-allocation" reservation */
787 resblks = 0;
788 error = xfs_trans_reserve(tp, 0, log_res, 0,
789 XFS_TRANS_PERM_LOG_RES, log_count);
790 }
791 if (error) {
792 cancel_flags = 0;
793 goto out_trans_cancel;
794 }
795
796 xfs_ilock(dp, XFS_ILOCK_EXCL | XFS_ILOCK_PARENT);
797 unlock_dp_on_error = B_TRUE;
798
799 xfs_bmap_init(&free_list, &first_block);
800
801 /*
802 * Reserve disk quota and the inode.
803 */
804 error = xfs_trans_reserve_quota(tp, mp, udqp, gdqp, resblks, 1, 0);
805 if (error)
806 goto out_trans_cancel;
807
808 error = xfs_dir_canenter(tp, dp, name, resblks);
809 if (error)
810 goto out_trans_cancel;
811
812 /*
813 * A newly created regular or special file just has one directory
814 * entry pointing to them, but a directory also the "." entry
815 * pointing to itself.
816 */
817 error = xfs_dir_ialloc(&tp, dp, mode, is_dir ? 2 : 1, rdev,
818 prid, resblks > 0, &ip, &committed);
819 if (error) {
820 if (error == ENOSPC)
821 goto out_trans_cancel;
822 goto out_trans_abort;
823 }
824
825 /*
826 * Now we join the directory inode to the transaction. We do not do it
827 * earlier because xfs_dir_ialloc might commit the previous transaction
828 * (and release all the locks). An error from here on will result in
829 * the transaction cancel unlocking dp so don't do it explicitly in the
830 * error path.
831 */
832 xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
833 unlock_dp_on_error = B_FALSE;
834
835 error = xfs_dir_createname(tp, dp, name, ip->i_ino,
836 &first_block, &free_list, resblks ?
837 resblks - XFS_IALLOC_SPACE_RES(mp) : 0);
838 if (error) {
839 ASSERT(error != ENOSPC);
840 goto out_trans_abort;
841 }
842 xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
843 xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
844
845 if (is_dir) {
846 error = xfs_dir_init(tp, ip, dp);
847 if (error)
848 goto out_bmap_cancel;
849
850 error = xfs_bumplink(tp, dp);
851 if (error)
852 goto out_bmap_cancel;
853 }
854
855 /*
856 * If this is a synchronous mount, make sure that the
857 * create transaction goes to disk before returning to
858 * the user.
859 */
860 if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
861 xfs_trans_set_sync(tp);
862
863 /*
864 * Attach the dquot(s) to the inodes and modify them incore.
865 * These ids of the inode couldn't have changed since the new
866 * inode has been locked ever since it was created.
867 */
868 xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp);
869
870 error = xfs_bmap_finish(&tp, &free_list, &committed);
871 if (error)
872 goto out_bmap_cancel;
873
874 error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
875 if (error)
876 goto out_release_inode;
877
878 xfs_qm_dqrele(udqp);
879 xfs_qm_dqrele(gdqp);
880
881 *ipp = ip;
882 return 0;
883
884 out_bmap_cancel:
885 xfs_bmap_cancel(&free_list);
886 out_trans_abort:
887 cancel_flags |= XFS_TRANS_ABORT;
888 out_trans_cancel:
889 xfs_trans_cancel(tp, cancel_flags);
890 out_release_inode:
891 /*
892 * Wait until after the current transaction is aborted to
893 * release the inode. This prevents recursive transactions
894 * and deadlocks from xfs_inactive.
895 */
896 if (ip)
897 IRELE(ip);
898
899 xfs_qm_dqrele(udqp);
900 xfs_qm_dqrele(gdqp);
901
902 if (unlock_dp_on_error)
903 xfs_iunlock(dp, XFS_ILOCK_EXCL);
904 return error;
905}
906
907#ifdef DEBUG
908int xfs_locked_n;
909int xfs_small_retries;
910int xfs_middle_retries;
911int xfs_lots_retries;
912int xfs_lock_delays;
913#endif
914
915/*
916 * Bump the subclass so xfs_lock_inodes() acquires each lock with
917 * a different value
918 */
919static inline int
920xfs_lock_inumorder(int lock_mode, int subclass)
921{
922 if (lock_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL))
923 lock_mode |= (subclass + XFS_LOCK_INUMORDER) << XFS_IOLOCK_SHIFT;
924 if (lock_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL))
925 lock_mode |= (subclass + XFS_LOCK_INUMORDER) << XFS_ILOCK_SHIFT;
926
927 return lock_mode;
928}
929
930/*
931 * The following routine will lock n inodes in exclusive mode.
932 * We assume the caller calls us with the inodes in i_ino order.
933 *
934 * We need to detect deadlock where an inode that we lock
935 * is in the AIL and we start waiting for another inode that is locked
936 * by a thread in a long running transaction (such as truncate). This can
937 * result in deadlock since the long running trans might need to wait
938 * for the inode we just locked in order to push the tail and free space
939 * in the log.
940 */
941void
942xfs_lock_inodes(
943 xfs_inode_t **ips,
944 int inodes,
945 uint lock_mode)
946{
947 int attempts = 0, i, j, try_lock;
948 xfs_log_item_t *lp;
949
950 ASSERT(ips && (inodes >= 2)); /* we need at least two */
951
952 try_lock = 0;
953 i = 0;
954
955again:
956 for (; i < inodes; i++) {
957 ASSERT(ips[i]);
958
959 if (i && (ips[i] == ips[i-1])) /* Already locked */
960 continue;
961
962 /*
963 * If try_lock is not set yet, make sure all locked inodes
964 * are not in the AIL.
965 * If any are, set try_lock to be used later.
966 */
967
968 if (!try_lock) {
969 for (j = (i - 1); j >= 0 && !try_lock; j--) {
970 lp = (xfs_log_item_t *)ips[j]->i_itemp;
971 if (lp && (lp->li_flags & XFS_LI_IN_AIL)) {
972 try_lock++;
973 }
974 }
975 }
976
977 /*
978 * If any of the previous locks we have locked is in the AIL,
979 * we must TRY to get the second and subsequent locks. If
980 * we can't get any, we must release all we have
981 * and try again.
982 */
983
984 if (try_lock) {
985 /* try_lock must be 0 if i is 0. */
986 /*
987 * try_lock means we have an inode locked
988 * that is in the AIL.
989 */
990 ASSERT(i != 0);
991 if (!xfs_ilock_nowait(ips[i], xfs_lock_inumorder(lock_mode, i))) {
992 attempts++;
993
994 /*
995 * Unlock all previous guys and try again.
996 * xfs_iunlock will try to push the tail
997 * if the inode is in the AIL.
998 */
999
1000 for(j = i - 1; j >= 0; j--) {
1001
1002 /*
1003 * Check to see if we've already
1004 * unlocked this one.
1005 * Not the first one going back,
1006 * and the inode ptr is the same.
1007 */
1008 if ((j != (i - 1)) && ips[j] ==
1009 ips[j+1])
1010 continue;
1011
1012 xfs_iunlock(ips[j], lock_mode);
1013 }
1014
1015 if ((attempts % 5) == 0) {
1016 delay(1); /* Don't just spin the CPU */
1017#ifdef DEBUG
1018 xfs_lock_delays++;
1019#endif
1020 }
1021 i = 0;
1022 try_lock = 0;
1023 goto again;
1024 }
1025 } else {
1026 xfs_ilock(ips[i], xfs_lock_inumorder(lock_mode, i));
1027 }
1028 }
1029
1030#ifdef DEBUG
1031 if (attempts) {
1032 if (attempts < 5) xfs_small_retries++;
1033 else if (attempts < 100) xfs_middle_retries++;
1034 else xfs_lots_retries++;
1035 } else {
1036 xfs_locked_n++;
1037 }
1038#endif
1039}
1040
1041/*
1042 * xfs_lock_two_inodes() can only be used to lock one type of lock
1043 * at a time - the iolock or the ilock, but not both at once. If
1044 * we lock both at once, lockdep will report false positives saying
1045 * we have violated locking orders.
1046 */
1047void
1048xfs_lock_two_inodes(
1049 xfs_inode_t *ip0,
1050 xfs_inode_t *ip1,
1051 uint lock_mode)
1052{
1053 xfs_inode_t *temp;
1054 int attempts = 0;
1055 xfs_log_item_t *lp;
1056
1057 if (lock_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL))
1058 ASSERT((lock_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)) == 0);
1059 ASSERT(ip0->i_ino != ip1->i_ino);
1060
1061 if (ip0->i_ino > ip1->i_ino) {
1062 temp = ip0;
1063 ip0 = ip1;
1064 ip1 = temp;
1065 }
1066
1067 again:
1068 xfs_ilock(ip0, xfs_lock_inumorder(lock_mode, 0));
1069
1070 /*
1071 * If the first lock we have locked is in the AIL, we must TRY to get
1072 * the second lock. If we can't get it, we must release the first one
1073 * and try again.
1074 */
1075 lp = (xfs_log_item_t *)ip0->i_itemp;
1076 if (lp && (lp->li_flags & XFS_LI_IN_AIL)) {
1077 if (!xfs_ilock_nowait(ip1, xfs_lock_inumorder(lock_mode, 1))) {
1078 xfs_iunlock(ip0, lock_mode);
1079 if ((++attempts % 5) == 0)
1080 delay(1); /* Don't just spin the CPU */
1081 goto again;
1082 }
1083 } else {
1084 xfs_ilock(ip1, xfs_lock_inumorder(lock_mode, 1));
1085 }
1086}
1087
1088int
1089xfs_remove(
1090 xfs_inode_t *dp,
1091 struct xfs_name *name,
1092 xfs_inode_t *ip)
1093{
1094 xfs_mount_t *mp = dp->i_mount;
1095 xfs_trans_t *tp = NULL;
1096 int is_dir = S_ISDIR(ip->i_d.di_mode);
1097 int error = 0;
1098 xfs_bmap_free_t free_list;
1099 xfs_fsblock_t first_block;
1100 int cancel_flags;
1101 int committed;
1102 int link_zero;
1103 uint resblks;
1104 uint log_count;
1105
1106 trace_xfs_remove(dp, name);
1107
1108 if (XFS_FORCED_SHUTDOWN(mp))
1109 return XFS_ERROR(EIO);
1110
1111 error = xfs_qm_dqattach(dp, 0);
1112 if (error)
1113 goto std_return;
1114
1115 error = xfs_qm_dqattach(ip, 0);
1116 if (error)
1117 goto std_return;
1118
1119 if (is_dir) {
1120 tp = xfs_trans_alloc(mp, XFS_TRANS_RMDIR);
1121 log_count = XFS_DEFAULT_LOG_COUNT;
1122 } else {
1123 tp = xfs_trans_alloc(mp, XFS_TRANS_REMOVE);
1124 log_count = XFS_REMOVE_LOG_COUNT;
1125 }
1126 cancel_flags = XFS_TRANS_RELEASE_LOG_RES;
1127
1128 /*
1129 * We try to get the real space reservation first,
1130 * allowing for directory btree deletion(s) implying
1131 * possible bmap insert(s). If we can't get the space
1132 * reservation then we use 0 instead, and avoid the bmap
1133 * btree insert(s) in the directory code by, if the bmap
1134 * insert tries to happen, instead trimming the LAST
1135 * block from the directory.
1136 */
1137 resblks = XFS_REMOVE_SPACE_RES(mp);
1138 error = xfs_trans_reserve(tp, resblks, XFS_REMOVE_LOG_RES(mp), 0,
1139 XFS_TRANS_PERM_LOG_RES, log_count);
1140 if (error == ENOSPC) {
1141 resblks = 0;
1142 error = xfs_trans_reserve(tp, 0, XFS_REMOVE_LOG_RES(mp), 0,
1143 XFS_TRANS_PERM_LOG_RES, log_count);
1144 }
1145 if (error) {
1146 ASSERT(error != ENOSPC);
1147 cancel_flags = 0;
1148 goto out_trans_cancel;
1149 }
1150
1151 xfs_lock_two_inodes(dp, ip, XFS_ILOCK_EXCL);
1152
1153 xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
1154 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
1155
1156 /*
1157 * If we're removing a directory perform some additional validation.
1158 */
1159 if (is_dir) {
1160 ASSERT(ip->i_d.di_nlink >= 2);
1161 if (ip->i_d.di_nlink != 2) {
1162 error = XFS_ERROR(ENOTEMPTY);
1163 goto out_trans_cancel;
1164 }
1165 if (!xfs_dir_isempty(ip)) {
1166 error = XFS_ERROR(ENOTEMPTY);
1167 goto out_trans_cancel;
1168 }
1169 }
1170
1171 xfs_bmap_init(&free_list, &first_block);
1172 error = xfs_dir_removename(tp, dp, name, ip->i_ino,
1173 &first_block, &free_list, resblks);
1174 if (error) {
1175 ASSERT(error != ENOENT);
1176 goto out_bmap_cancel;
1177 }
1178 xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1179
1180 if (is_dir) {
1181 /*
1182 * Drop the link from ip's "..".
1183 */
1184 error = xfs_droplink(tp, dp);
1185 if (error)
1186 goto out_bmap_cancel;
1187
1188 /*
1189 * Drop the "." link from ip to self.
1190 */
1191 error = xfs_droplink(tp, ip);
1192 if (error)
1193 goto out_bmap_cancel;
1194 } else {
1195 /*
1196 * When removing a non-directory we need to log the parent
1197 * inode here. For a directory this is done implicitly
1198 * by the xfs_droplink call for the ".." entry.
1199 */
1200 xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
1201 }
1202
1203 /*
1204 * Drop the link from dp to ip.
1205 */
1206 error = xfs_droplink(tp, ip);
1207 if (error)
1208 goto out_bmap_cancel;
1209
1210 /*
1211 * Determine if this is the last link while
1212 * we are in the transaction.
1213 */
1214 link_zero = (ip->i_d.di_nlink == 0);
1215
1216 /*
1217 * If this is a synchronous mount, make sure that the
1218 * remove transaction goes to disk before returning to
1219 * the user.
1220 */
1221 if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
1222 xfs_trans_set_sync(tp);
1223
1224 error = xfs_bmap_finish(&tp, &free_list, &committed);
1225 if (error)
1226 goto out_bmap_cancel;
1227
1228 error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
1229 if (error)
1230 goto std_return;
1231
1232 /*
1233 * If we are using filestreams, kill the stream association.
1234 * If the file is still open it may get a new one but that
1235 * will get killed on last close in xfs_close() so we don't
1236 * have to worry about that.
1237 */
1238 if (!is_dir && link_zero && xfs_inode_is_filestream(ip))
1239 xfs_filestream_deassociate(ip);
1240
1241 return 0;
1242
1243 out_bmap_cancel:
1244 xfs_bmap_cancel(&free_list);
1245 cancel_flags |= XFS_TRANS_ABORT;
1246 out_trans_cancel:
1247 xfs_trans_cancel(tp, cancel_flags);
1248 std_return:
1249 return error;
1250}
1251
1252int
1253xfs_link(
1254 xfs_inode_t *tdp,
1255 xfs_inode_t *sip,
1256 struct xfs_name *target_name)
1257{
1258 xfs_mount_t *mp = tdp->i_mount;
1259 xfs_trans_t *tp;
1260 int error;
1261 xfs_bmap_free_t free_list;
1262 xfs_fsblock_t first_block;
1263 int cancel_flags;
1264 int committed;
1265 int resblks;
1266
1267 trace_xfs_link(tdp, target_name);
1268
1269 ASSERT(!S_ISDIR(sip->i_d.di_mode));
1270
1271 if (XFS_FORCED_SHUTDOWN(mp))
1272 return XFS_ERROR(EIO);
1273
1274 error = xfs_qm_dqattach(sip, 0);
1275 if (error)
1276 goto std_return;
1277
1278 error = xfs_qm_dqattach(tdp, 0);
1279 if (error)
1280 goto std_return;
1281
1282 tp = xfs_trans_alloc(mp, XFS_TRANS_LINK);
1283 cancel_flags = XFS_TRANS_RELEASE_LOG_RES;
1284 resblks = XFS_LINK_SPACE_RES(mp, target_name->len);
1285 error = xfs_trans_reserve(tp, resblks, XFS_LINK_LOG_RES(mp), 0,
1286 XFS_TRANS_PERM_LOG_RES, XFS_LINK_LOG_COUNT);
1287 if (error == ENOSPC) {
1288 resblks = 0;
1289 error = xfs_trans_reserve(tp, 0, XFS_LINK_LOG_RES(mp), 0,
1290 XFS_TRANS_PERM_LOG_RES, XFS_LINK_LOG_COUNT);
1291 }
1292 if (error) {
1293 cancel_flags = 0;
1294 goto error_return;
1295 }
1296
1297 xfs_lock_two_inodes(sip, tdp, XFS_ILOCK_EXCL);
1298
1299 xfs_trans_ijoin(tp, sip, XFS_ILOCK_EXCL);
1300 xfs_trans_ijoin(tp, tdp, XFS_ILOCK_EXCL);
1301
1302 /*
1303 * If we are using project inheritance, we only allow hard link
1304 * creation in our tree when the project IDs are the same; else
1305 * the tree quota mechanism could be circumvented.
1306 */
1307 if (unlikely((tdp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) &&
1308 (xfs_get_projid(tdp) != xfs_get_projid(sip)))) {
1309 error = XFS_ERROR(EXDEV);
1310 goto error_return;
1311 }
1312
1313 error = xfs_dir_canenter(tp, tdp, target_name, resblks);
1314 if (error)
1315 goto error_return;
1316
1317 xfs_bmap_init(&free_list, &first_block);
1318
1319 error = xfs_dir_createname(tp, tdp, target_name, sip->i_ino,
1320 &first_block, &free_list, resblks);
1321 if (error)
1322 goto abort_return;
1323 xfs_trans_ichgtime(tp, tdp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1324 xfs_trans_log_inode(tp, tdp, XFS_ILOG_CORE);
1325
1326 error = xfs_bumplink(tp, sip);
1327 if (error)
1328 goto abort_return;
1329
1330 /*
1331 * If this is a synchronous mount, make sure that the
1332 * link transaction goes to disk before returning to
1333 * the user.
1334 */
1335 if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC)) {
1336 xfs_trans_set_sync(tp);
1337 }
1338
1339 error = xfs_bmap_finish (&tp, &free_list, &committed);
1340 if (error) {
1341 xfs_bmap_cancel(&free_list);
1342 goto abort_return;
1343 }
1344
1345 return xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
1346
1347 abort_return:
1348 cancel_flags |= XFS_TRANS_ABORT;
1349 error_return:
1350 xfs_trans_cancel(tp, cancel_flags);
1351 std_return:
1352 return error;
1353}
1354
1355int
1356xfs_symlink(
1357 xfs_inode_t *dp,
1358 struct xfs_name *link_name,
1359 const char *target_path,
1360 umode_t mode,
1361 xfs_inode_t **ipp)
1362{
1363 xfs_mount_t *mp = dp->i_mount;
1364 xfs_trans_t *tp;
1365 xfs_inode_t *ip;
1366 int error;
1367 int pathlen;
1368 xfs_bmap_free_t free_list;
1369 xfs_fsblock_t first_block;
1370 boolean_t unlock_dp_on_error = B_FALSE;
1371 uint cancel_flags;
1372 int committed;
1373 xfs_fileoff_t first_fsb;
1374 xfs_filblks_t fs_blocks;
1375 int nmaps;
1376 xfs_bmbt_irec_t mval[SYMLINK_MAPS];
1377 xfs_daddr_t d;
1378 const char *cur_chunk;
1379 int byte_cnt;
1380 int n;
1381 xfs_buf_t *bp;
1382 prid_t prid;
1383 struct xfs_dquot *udqp, *gdqp;
1384 uint resblks;
1385
1386 *ipp = NULL;
1387 error = 0;
1388 ip = NULL;
1389 tp = NULL;
1390
1391 trace_xfs_symlink(dp, link_name);
1392
1393 if (XFS_FORCED_SHUTDOWN(mp))
1394 return XFS_ERROR(EIO);
1395
1396 /*
1397 * Check component lengths of the target path name.
1398 */
1399 pathlen = strlen(target_path);
1400 if (pathlen >= MAXPATHLEN) /* total string too long */
1401 return XFS_ERROR(ENAMETOOLONG);
1402
1403 udqp = gdqp = NULL;
1404 if (dp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT)
1405 prid = xfs_get_projid(dp);
1406 else
1407 prid = XFS_PROJID_DEFAULT;
1408
1409 /*
1410 * Make sure that we have allocated dquot(s) on disk.
1411 */
1412 error = xfs_qm_vop_dqalloc(dp, current_fsuid(), current_fsgid(), prid,
1413 XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT, &udqp, &gdqp);
1414 if (error)
1415 goto std_return;
1416
1417 tp = xfs_trans_alloc(mp, XFS_TRANS_SYMLINK);
1418 cancel_flags = XFS_TRANS_RELEASE_LOG_RES;
1419 /*
1420 * The symlink will fit into the inode data fork?
1421 * There can't be any attributes so we get the whole variable part.
1422 */
1423 if (pathlen <= XFS_LITINO(mp))
1424 fs_blocks = 0;
1425 else
1426 fs_blocks = XFS_B_TO_FSB(mp, pathlen);
1427 resblks = XFS_SYMLINK_SPACE_RES(mp, link_name->len, fs_blocks);
1428 error = xfs_trans_reserve(tp, resblks, XFS_SYMLINK_LOG_RES(mp), 0,
1429 XFS_TRANS_PERM_LOG_RES, XFS_SYMLINK_LOG_COUNT);
1430 if (error == ENOSPC && fs_blocks == 0) {
1431 resblks = 0;
1432 error = xfs_trans_reserve(tp, 0, XFS_SYMLINK_LOG_RES(mp), 0,
1433 XFS_TRANS_PERM_LOG_RES, XFS_SYMLINK_LOG_COUNT);
1434 }
1435 if (error) {
1436 cancel_flags = 0;
1437 goto error_return;
1438 }
1439
1440 xfs_ilock(dp, XFS_ILOCK_EXCL | XFS_ILOCK_PARENT);
1441 unlock_dp_on_error = B_TRUE;
1442
1443 /*
1444 * Check whether the directory allows new symlinks or not.
1445 */
1446 if (dp->i_d.di_flags & XFS_DIFLAG_NOSYMLINKS) {
1447 error = XFS_ERROR(EPERM);
1448 goto error_return;
1449 }
1450
1451 /*
1452 * Reserve disk quota : blocks and inode.
1453 */
1454 error = xfs_trans_reserve_quota(tp, mp, udqp, gdqp, resblks, 1, 0);
1455 if (error)
1456 goto error_return;
1457
1458 /*
1459 * Check for ability to enter directory entry, if no space reserved.
1460 */
1461 error = xfs_dir_canenter(tp, dp, link_name, resblks);
1462 if (error)
1463 goto error_return;
1464 /*
1465 * Initialize the bmap freelist prior to calling either
1466 * bmapi or the directory create code.
1467 */
1468 xfs_bmap_init(&free_list, &first_block);
1469
1470 /*
1471 * Allocate an inode for the symlink.
1472 */
1473 error = xfs_dir_ialloc(&tp, dp, S_IFLNK | (mode & ~S_IFMT), 1, 0,
1474 prid, resblks > 0, &ip, NULL);
1475 if (error) {
1476 if (error == ENOSPC)
1477 goto error_return;
1478 goto error1;
1479 }
1480
1481 /*
1482 * An error after we've joined dp to the transaction will result in the
1483 * transaction cancel unlocking dp so don't do it explicitly in the
1484 * error path.
1485 */
1486 xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
1487 unlock_dp_on_error = B_FALSE;
1488
1489 /*
1490 * Also attach the dquot(s) to it, if applicable.
1491 */
1492 xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp);
1493
1494 if (resblks)
1495 resblks -= XFS_IALLOC_SPACE_RES(mp);
1496 /*
1497 * If the symlink will fit into the inode, write it inline.
1498 */
1499 if (pathlen <= XFS_IFORK_DSIZE(ip)) {
1500 xfs_idata_realloc(ip, pathlen, XFS_DATA_FORK);
1501 memcpy(ip->i_df.if_u1.if_data, target_path, pathlen);
1502 ip->i_d.di_size = pathlen;
1503
1504 /*
1505 * The inode was initially created in extent format.
1506 */
1507 ip->i_df.if_flags &= ~(XFS_IFEXTENTS | XFS_IFBROOT);
1508 ip->i_df.if_flags |= XFS_IFINLINE;
1509
1510 ip->i_d.di_format = XFS_DINODE_FMT_LOCAL;
1511 xfs_trans_log_inode(tp, ip, XFS_ILOG_DDATA | XFS_ILOG_CORE);
1512
1513 } else {
1514 first_fsb = 0;
1515 nmaps = SYMLINK_MAPS;
1516
1517 error = xfs_bmapi_write(tp, ip, first_fsb, fs_blocks,
1518 XFS_BMAPI_METADATA, &first_block, resblks,
1519 mval, &nmaps, &free_list);
1520 if (error)
1521 goto error2;
1522
1523 if (resblks)
1524 resblks -= fs_blocks;
1525 ip->i_d.di_size = pathlen;
1526 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1527
1528 cur_chunk = target_path;
1529 for (n = 0; n < nmaps; n++) {
1530 d = XFS_FSB_TO_DADDR(mp, mval[n].br_startblock);
1531 byte_cnt = XFS_FSB_TO_B(mp, mval[n].br_blockcount);
1532 bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, d,
1533 BTOBB(byte_cnt), 0);
1534 if (!bp) {
1535 error = ENOMEM;
1536 goto error2;
1537 }
1538 if (pathlen < byte_cnt) {
1539 byte_cnt = pathlen;
1540 }
1541 pathlen -= byte_cnt;
1542
1543 memcpy(bp->b_addr, cur_chunk, byte_cnt);
1544 cur_chunk += byte_cnt;
1545
1546 xfs_trans_log_buf(tp, bp, 0, byte_cnt - 1);
1547 }
1548 }
1549
1550 /*
1551 * Create the directory entry for the symlink.
1552 */
1553 error = xfs_dir_createname(tp, dp, link_name, ip->i_ino,
1554 &first_block, &free_list, resblks);
1555 if (error)
1556 goto error2;
1557 xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1558 xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
1559
1560 /*
1561 * If this is a synchronous mount, make sure that the
1562 * symlink transaction goes to disk before returning to
1563 * the user.
1564 */
1565 if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC)) {
1566 xfs_trans_set_sync(tp);
1567 }
1568
1569 error = xfs_bmap_finish(&tp, &free_list, &committed);
1570 if (error) {
1571 goto error2;
1572 }
1573 error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
1574 xfs_qm_dqrele(udqp);
1575 xfs_qm_dqrele(gdqp);
1576
1577 *ipp = ip;
1578 return 0;
1579
1580 error2:
1581 IRELE(ip);
1582 error1:
1583 xfs_bmap_cancel(&free_list);
1584 cancel_flags |= XFS_TRANS_ABORT;
1585 error_return:
1586 xfs_trans_cancel(tp, cancel_flags);
1587 xfs_qm_dqrele(udqp);
1588 xfs_qm_dqrele(gdqp);
1589
1590 if (unlock_dp_on_error)
1591 xfs_iunlock(dp, XFS_ILOCK_EXCL);
1592 std_return:
1593 return error;
1594}
1595
1596int
1597xfs_set_dmattrs(
1598 xfs_inode_t *ip,
1599 u_int evmask,
1600 u_int16_t state)
1601{
1602 xfs_mount_t *mp = ip->i_mount;
1603 xfs_trans_t *tp;
1604 int error;
1605
1606 if (!capable(CAP_SYS_ADMIN))
1607 return XFS_ERROR(EPERM);
1608
1609 if (XFS_FORCED_SHUTDOWN(mp))
1610 return XFS_ERROR(EIO);
1611
1612 tp = xfs_trans_alloc(mp, XFS_TRANS_SET_DMATTRS);
1613 error = xfs_trans_reserve(tp, 0, XFS_ICHANGE_LOG_RES (mp), 0, 0, 0);
1614 if (error) {
1615 xfs_trans_cancel(tp, 0);
1616 return error;
1617 }
1618 xfs_ilock(ip, XFS_ILOCK_EXCL);
1619 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
1620
1621 ip->i_d.di_dmevmask = evmask;
1622 ip->i_d.di_dmstate = state;
1623
1624 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1625 error = xfs_trans_commit(tp, 0);
1626
1627 return error;
1628}
1629
1630/*
1631 * xfs_alloc_file_space()
1632 * This routine allocates disk space for the given file.
1633 *
1634 * If alloc_type == 0, this request is for an ALLOCSP type
1635 * request which will change the file size. In this case, no
1636 * DMAPI event will be generated by the call. A TRUNCATE event
1637 * will be generated later by xfs_setattr.
1638 *
1639 * If alloc_type != 0, this request is for a RESVSP type
1640 * request, and a DMAPI DM_EVENT_WRITE will be generated if the
1641 * lower block boundary byte address is less than the file's
1642 * length.
1643 *
1644 * RETURNS:
1645 * 0 on success
1646 * errno on error
1647 *
1648 */
1649STATIC int
1650xfs_alloc_file_space(
1651 xfs_inode_t *ip,
1652 xfs_off_t offset,
1653 xfs_off_t len,
1654 int alloc_type,
1655 int attr_flags)
1656{
1657 xfs_mount_t *mp = ip->i_mount;
1658 xfs_off_t count;
1659 xfs_filblks_t allocated_fsb;
1660 xfs_filblks_t allocatesize_fsb;
1661 xfs_extlen_t extsz, temp;
1662 xfs_fileoff_t startoffset_fsb;
1663 xfs_fsblock_t firstfsb;
1664 int nimaps;
1665 int quota_flag;
1666 int rt;
1667 xfs_trans_t *tp;
1668 xfs_bmbt_irec_t imaps[1], *imapp;
1669 xfs_bmap_free_t free_list;
1670 uint qblocks, resblks, resrtextents;
1671 int committed;
1672 int error;
1673
1674 trace_xfs_alloc_file_space(ip);
1675
1676 if (XFS_FORCED_SHUTDOWN(mp))
1677 return XFS_ERROR(EIO);
1678
1679 error = xfs_qm_dqattach(ip, 0);
1680 if (error)
1681 return error;
1682
1683 if (len <= 0)
1684 return XFS_ERROR(EINVAL);
1685
1686 rt = XFS_IS_REALTIME_INODE(ip);
1687 extsz = xfs_get_extsz_hint(ip);
1688
1689 count = len;
1690 imapp = &imaps[0];
1691 nimaps = 1;
1692 startoffset_fsb = XFS_B_TO_FSBT(mp, offset);
1693 allocatesize_fsb = XFS_B_TO_FSB(mp, count);
1694
1695 /*
1696 * Allocate file space until done or until there is an error
1697 */
1698 while (allocatesize_fsb && !error) {
1699 xfs_fileoff_t s, e;
1700
1701 /*
1702 * Determine space reservations for data/realtime.
1703 */
1704 if (unlikely(extsz)) {
1705 s = startoffset_fsb;
1706 do_div(s, extsz);
1707 s *= extsz;
1708 e = startoffset_fsb + allocatesize_fsb;
1709 if ((temp = do_mod(startoffset_fsb, extsz)))
1710 e += temp;
1711 if ((temp = do_mod(e, extsz)))
1712 e += extsz - temp;
1713 } else {
1714 s = 0;
1715 e = allocatesize_fsb;
1716 }
1717
1718 /*
1719 * The transaction reservation is limited to a 32-bit block
1720 * count, hence we need to limit the number of blocks we are
1721 * trying to reserve to avoid an overflow. We can't allocate
1722 * more than @nimaps extents, and an extent is limited on disk
1723 * to MAXEXTLEN (21 bits), so use that to enforce the limit.
1724 */
1725 resblks = min_t(xfs_fileoff_t, (e - s), (MAXEXTLEN * nimaps));
1726 if (unlikely(rt)) {
1727 resrtextents = qblocks = resblks;
1728 resrtextents /= mp->m_sb.sb_rextsize;
1729 resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0);
1730 quota_flag = XFS_QMOPT_RES_RTBLKS;
1731 } else {
1732 resrtextents = 0;
1733 resblks = qblocks = XFS_DIOSTRAT_SPACE_RES(mp, resblks);
1734 quota_flag = XFS_QMOPT_RES_REGBLKS;
1735 }
1736
1737 /*
1738 * Allocate and setup the transaction.
1739 */
1740 tp = xfs_trans_alloc(mp, XFS_TRANS_DIOSTRAT);
1741 error = xfs_trans_reserve(tp, resblks,
1742 XFS_WRITE_LOG_RES(mp), resrtextents,
1743 XFS_TRANS_PERM_LOG_RES,
1744 XFS_WRITE_LOG_COUNT);
1745 /*
1746 * Check for running out of space
1747 */
1748 if (error) {
1749 /*
1750 * Free the transaction structure.
1751 */
1752 ASSERT(error == ENOSPC || XFS_FORCED_SHUTDOWN(mp));
1753 xfs_trans_cancel(tp, 0);
1754 break;
1755 }
1756 xfs_ilock(ip, XFS_ILOCK_EXCL);
1757 error = xfs_trans_reserve_quota_nblks(tp, ip, qblocks,
1758 0, quota_flag);
1759 if (error)
1760 goto error1;
1761
1762 xfs_trans_ijoin(tp, ip, 0);
1763
1764 xfs_bmap_init(&free_list, &firstfsb);
1765 error = xfs_bmapi_write(tp, ip, startoffset_fsb,
1766 allocatesize_fsb, alloc_type, &firstfsb,
1767 0, imapp, &nimaps, &free_list);
1768 if (error) {
1769 goto error0;
1770 }
1771
1772 /*
1773 * Complete the transaction
1774 */
1775 error = xfs_bmap_finish(&tp, &free_list, &committed);
1776 if (error) {
1777 goto error0;
1778 }
1779
1780 error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
1781 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1782 if (error) {
1783 break;
1784 }
1785
1786 allocated_fsb = imapp->br_blockcount;
1787
1788 if (nimaps == 0) {
1789 error = XFS_ERROR(ENOSPC);
1790 break;
1791 }
1792
1793 startoffset_fsb += allocated_fsb;
1794 allocatesize_fsb -= allocated_fsb;
1795 }
1796
1797 return error;
1798
1799error0: /* Cancel bmap, unlock inode, unreserve quota blocks, cancel trans */
1800 xfs_bmap_cancel(&free_list);
1801 xfs_trans_unreserve_quota_nblks(tp, ip, (long)qblocks, 0, quota_flag);
1802
1803error1: /* Just cancel transaction */
1804 xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
1805 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1806 return error;
1807}
1808
1809/*
1810 * Zero file bytes between startoff and endoff inclusive.
1811 * The iolock is held exclusive and no blocks are buffered.
1812 *
1813 * This function is used by xfs_free_file_space() to zero
1814 * partial blocks when the range to free is not block aligned.
1815 * When unreserving space with boundaries that are not block
1816 * aligned we round up the start and round down the end
1817 * boundaries and then use this function to zero the parts of
1818 * the blocks that got dropped during the rounding.
1819 */
1820STATIC int
1821xfs_zero_remaining_bytes(
1822 xfs_inode_t *ip,
1823 xfs_off_t startoff,
1824 xfs_off_t endoff)
1825{
1826 xfs_bmbt_irec_t imap;
1827 xfs_fileoff_t offset_fsb;
1828 xfs_off_t lastoffset;
1829 xfs_off_t offset;
1830 xfs_buf_t *bp;
1831 xfs_mount_t *mp = ip->i_mount;
1832 int nimap;
1833 int error = 0;
1834
1835 /*
1836 * Avoid doing I/O beyond eof - it's not necessary
1837 * since nothing can read beyond eof. The space will
1838 * be zeroed when the file is extended anyway.
1839 */
1840 if (startoff >= XFS_ISIZE(ip))
1841 return 0;
1842
1843 if (endoff > XFS_ISIZE(ip))
1844 endoff = XFS_ISIZE(ip);
1845
1846 bp = xfs_buf_get_uncached(XFS_IS_REALTIME_INODE(ip) ?
1847 mp->m_rtdev_targp : mp->m_ddev_targp,
1848 BTOBB(mp->m_sb.sb_blocksize), 0);
1849 if (!bp)
1850 return XFS_ERROR(ENOMEM);
1851
1852 xfs_buf_unlock(bp);
1853
1854 for (offset = startoff; offset <= endoff; offset = lastoffset + 1) {
1855 offset_fsb = XFS_B_TO_FSBT(mp, offset);
1856 nimap = 1;
1857 error = xfs_bmapi_read(ip, offset_fsb, 1, &imap, &nimap, 0);
1858 if (error || nimap < 1)
1859 break;
1860 ASSERT(imap.br_blockcount >= 1);
1861 ASSERT(imap.br_startoff == offset_fsb);
1862 lastoffset = XFS_FSB_TO_B(mp, imap.br_startoff + 1) - 1;
1863 if (lastoffset > endoff)
1864 lastoffset = endoff;
1865 if (imap.br_startblock == HOLESTARTBLOCK)
1866 continue;
1867 ASSERT(imap.br_startblock != DELAYSTARTBLOCK);
1868 if (imap.br_state == XFS_EXT_UNWRITTEN)
1869 continue;
1870 XFS_BUF_UNDONE(bp);
1871 XFS_BUF_UNWRITE(bp);
1872 XFS_BUF_READ(bp);
1873 XFS_BUF_SET_ADDR(bp, xfs_fsb_to_db(ip, imap.br_startblock));
1874 xfsbdstrat(mp, bp);
1875 error = xfs_buf_iowait(bp);
1876 if (error) {
1877 xfs_buf_ioerror_alert(bp,
1878 "xfs_zero_remaining_bytes(read)");
1879 break;
1880 }
1881 memset(bp->b_addr +
1882 (offset - XFS_FSB_TO_B(mp, imap.br_startoff)),
1883 0, lastoffset - offset + 1);
1884 XFS_BUF_UNDONE(bp);
1885 XFS_BUF_UNREAD(bp);
1886 XFS_BUF_WRITE(bp);
1887 xfsbdstrat(mp, bp);
1888 error = xfs_buf_iowait(bp);
1889 if (error) {
1890 xfs_buf_ioerror_alert(bp,
1891 "xfs_zero_remaining_bytes(write)");
1892 break;
1893 }
1894 }
1895 xfs_buf_free(bp);
1896 return error;
1897}
1898
1899/*
1900 * xfs_free_file_space()
1901 * This routine frees disk space for the given file.
1902 *
1903 * This routine is only called by xfs_change_file_space
1904 * for an UNRESVSP type call.
1905 *
1906 * RETURNS:
1907 * 0 on success
1908 * errno on error
1909 *
1910 */
1911STATIC int
1912xfs_free_file_space(
1913 xfs_inode_t *ip,
1914 xfs_off_t offset,
1915 xfs_off_t len,
1916 int attr_flags)
1917{
1918 int committed;
1919 int done;
1920 xfs_fileoff_t endoffset_fsb;
1921 int error;
1922 xfs_fsblock_t firstfsb;
1923 xfs_bmap_free_t free_list;
1924 xfs_bmbt_irec_t imap;
1925 xfs_off_t ioffset;
1926 xfs_extlen_t mod=0;
1927 xfs_mount_t *mp;
1928 int nimap;
1929 uint resblks;
1930 uint rounding;
1931 int rt;
1932 xfs_fileoff_t startoffset_fsb;
1933 xfs_trans_t *tp;
1934 int need_iolock = 1;
1935
1936 mp = ip->i_mount;
1937
1938 trace_xfs_free_file_space(ip);
1939
1940 error = xfs_qm_dqattach(ip, 0);
1941 if (error)
1942 return error;
1943
1944 error = 0;
1945 if (len <= 0) /* if nothing being freed */
1946 return error;
1947 rt = XFS_IS_REALTIME_INODE(ip);
1948 startoffset_fsb = XFS_B_TO_FSB(mp, offset);
1949 endoffset_fsb = XFS_B_TO_FSBT(mp, offset + len);
1950
1951 if (attr_flags & XFS_ATTR_NOLOCK)
1952 need_iolock = 0;
1953 if (need_iolock) {
1954 xfs_ilock(ip, XFS_IOLOCK_EXCL);
1955 /* wait for the completion of any pending DIOs */
1956 inode_dio_wait(VFS_I(ip));
1957 }
1958
1959 rounding = max_t(uint, 1 << mp->m_sb.sb_blocklog, PAGE_CACHE_SIZE);
1960 ioffset = offset & ~(rounding - 1);
1961 error = -filemap_write_and_wait_range(VFS_I(ip)->i_mapping,
1962 ioffset, -1);
1963 if (error)
1964 goto out_unlock_iolock;
1965 truncate_pagecache_range(VFS_I(ip), ioffset, -1);
1966
1967 /*
1968 * Need to zero the stuff we're not freeing, on disk.
1969 * If it's a realtime file & can't use unwritten extents then we
1970 * actually need to zero the extent edges. Otherwise xfs_bunmapi
1971 * will take care of it for us.
1972 */
1973 if (rt && !xfs_sb_version_hasextflgbit(&mp->m_sb)) {
1974 nimap = 1;
1975 error = xfs_bmapi_read(ip, startoffset_fsb, 1,
1976 &imap, &nimap, 0);
1977 if (error)
1978 goto out_unlock_iolock;
1979 ASSERT(nimap == 0 || nimap == 1);
1980 if (nimap && imap.br_startblock != HOLESTARTBLOCK) {
1981 xfs_daddr_t block;
1982
1983 ASSERT(imap.br_startblock != DELAYSTARTBLOCK);
1984 block = imap.br_startblock;
1985 mod = do_div(block, mp->m_sb.sb_rextsize);
1986 if (mod)
1987 startoffset_fsb += mp->m_sb.sb_rextsize - mod;
1988 }
1989 nimap = 1;
1990 error = xfs_bmapi_read(ip, endoffset_fsb - 1, 1,
1991 &imap, &nimap, 0);
1992 if (error)
1993 goto out_unlock_iolock;
1994 ASSERT(nimap == 0 || nimap == 1);
1995 if (nimap && imap.br_startblock != HOLESTARTBLOCK) {
1996 ASSERT(imap.br_startblock != DELAYSTARTBLOCK);
1997 mod++;
1998 if (mod && (mod != mp->m_sb.sb_rextsize))
1999 endoffset_fsb -= mod;
2000 }
2001 }
2002 if ((done = (endoffset_fsb <= startoffset_fsb)))
2003 /*
2004 * One contiguous piece to clear
2005 */
2006 error = xfs_zero_remaining_bytes(ip, offset, offset + len - 1);
2007 else {
2008 /*
2009 * Some full blocks, possibly two pieces to clear
2010 */
2011 if (offset < XFS_FSB_TO_B(mp, startoffset_fsb))
2012 error = xfs_zero_remaining_bytes(ip, offset,
2013 XFS_FSB_TO_B(mp, startoffset_fsb) - 1);
2014 if (!error &&
2015 XFS_FSB_TO_B(mp, endoffset_fsb) < offset + len)
2016 error = xfs_zero_remaining_bytes(ip,
2017 XFS_FSB_TO_B(mp, endoffset_fsb),
2018 offset + len - 1);
2019 }
2020
2021 /*
2022 * free file space until done or until there is an error
2023 */
2024 resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0);
2025 while (!error && !done) {
2026
2027 /*
2028 * allocate and setup the transaction. Allow this
2029 * transaction to dip into the reserve blocks to ensure
2030 * the freeing of the space succeeds at ENOSPC.
2031 */
2032 tp = xfs_trans_alloc(mp, XFS_TRANS_DIOSTRAT);
2033 tp->t_flags |= XFS_TRANS_RESERVE;
2034 error = xfs_trans_reserve(tp,
2035 resblks,
2036 XFS_WRITE_LOG_RES(mp),
2037 0,
2038 XFS_TRANS_PERM_LOG_RES,
2039 XFS_WRITE_LOG_COUNT);
2040
2041 /*
2042 * check for running out of space
2043 */
2044 if (error) {
2045 /*
2046 * Free the transaction structure.
2047 */
2048 ASSERT(error == ENOSPC || XFS_FORCED_SHUTDOWN(mp));
2049 xfs_trans_cancel(tp, 0);
2050 break;
2051 }
2052 xfs_ilock(ip, XFS_ILOCK_EXCL);
2053 error = xfs_trans_reserve_quota(tp, mp,
2054 ip->i_udquot, ip->i_gdquot,
2055 resblks, 0, XFS_QMOPT_RES_REGBLKS);
2056 if (error)
2057 goto error1;
2058
2059 xfs_trans_ijoin(tp, ip, 0);
2060
2061 /*
2062 * issue the bunmapi() call to free the blocks
2063 */
2064 xfs_bmap_init(&free_list, &firstfsb);
2065 error = xfs_bunmapi(tp, ip, startoffset_fsb,
2066 endoffset_fsb - startoffset_fsb,
2067 0, 2, &firstfsb, &free_list, &done);
2068 if (error) {
2069 goto error0;
2070 }
2071
2072 /*
2073 * complete the transaction
2074 */
2075 error = xfs_bmap_finish(&tp, &free_list, &committed);
2076 if (error) {
2077 goto error0;
2078 }
2079
2080 error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
2081 xfs_iunlock(ip, XFS_ILOCK_EXCL);
2082 }
2083
2084 out_unlock_iolock:
2085 if (need_iolock)
2086 xfs_iunlock(ip, XFS_IOLOCK_EXCL);
2087 return error;
2088
2089 error0:
2090 xfs_bmap_cancel(&free_list);
2091 error1:
2092 xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
2093 xfs_iunlock(ip, need_iolock ? (XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL) :
2094 XFS_ILOCK_EXCL);
2095 return error;
2096}
2097
2098
2099STATIC int
2100xfs_zero_file_space(
2101 struct xfs_inode *ip,
2102 xfs_off_t offset,
2103 xfs_off_t len,
2104 int attr_flags)
2105{
2106 struct xfs_mount *mp = ip->i_mount;
2107 uint granularity;
2108 xfs_off_t start_boundary;
2109 xfs_off_t end_boundary;
2110 int error;
2111
2112 granularity = max_t(uint, 1 << mp->m_sb.sb_blocklog, PAGE_CACHE_SIZE);
2113
2114 /*
2115 * Round the range of extents we are going to convert inwards. If the
2116 * offset is aligned, then it doesn't get changed so we zero from the
2117 * start of the block offset points to.
2118 */
2119 start_boundary = round_up(offset, granularity);
2120 end_boundary = round_down(offset + len, granularity);
2121
2122 ASSERT(start_boundary >= offset);
2123 ASSERT(end_boundary <= offset + len);
2124
2125 if (!(attr_flags & XFS_ATTR_NOLOCK))
2126 xfs_ilock(ip, XFS_IOLOCK_EXCL);
2127
2128 if (start_boundary < end_boundary - 1) {
2129 /* punch out the page cache over the conversion range */
2130 truncate_pagecache_range(VFS_I(ip), start_boundary,
2131 end_boundary - 1);
2132 /* convert the blocks */
2133 error = xfs_alloc_file_space(ip, start_boundary,
2134 end_boundary - start_boundary - 1,
2135 XFS_BMAPI_PREALLOC | XFS_BMAPI_CONVERT,
2136 attr_flags);
2137 if (error)
2138 goto out_unlock;
2139
2140 /* We've handled the interior of the range, now for the edges */
2141 if (start_boundary != offset)
2142 error = xfs_iozero(ip, offset, start_boundary - offset);
2143 if (error)
2144 goto out_unlock;
2145
2146 if (end_boundary != offset + len)
2147 error = xfs_iozero(ip, end_boundary,
2148 offset + len - end_boundary);
2149
2150 } else {
2151 /*
2152 * It's either a sub-granularity range or the range spanned lies
2153 * partially across two adjacent blocks.
2154 */
2155 error = xfs_iozero(ip, offset, len);
2156 }
2157
2158out_unlock:
2159 if (!(attr_flags & XFS_ATTR_NOLOCK))
2160 xfs_iunlock(ip, XFS_IOLOCK_EXCL);
2161 return error;
2162
2163}
2164
2165/*
2166 * xfs_change_file_space()
2167 * This routine allocates or frees disk space for the given file.
2168 * The user specified parameters are checked for alignment and size
2169 * limitations.
2170 *
2171 * RETURNS:
2172 * 0 on success
2173 * errno on error
2174 *
2175 */
2176int
2177xfs_change_file_space(
2178 xfs_inode_t *ip,
2179 int cmd,
2180 xfs_flock64_t *bf,
2181 xfs_off_t offset,
2182 int attr_flags)
2183{
2184 xfs_mount_t *mp = ip->i_mount;
2185 int clrprealloc;
2186 int error;
2187 xfs_fsize_t fsize;
2188 int setprealloc;
2189 xfs_off_t startoffset;
2190 xfs_trans_t *tp;
2191 struct iattr iattr;
2192
2193 if (!S_ISREG(ip->i_d.di_mode))
2194 return XFS_ERROR(EINVAL);
2195
2196 switch (bf->l_whence) {
2197 case 0: /*SEEK_SET*/
2198 break;
2199 case 1: /*SEEK_CUR*/
2200 bf->l_start += offset;
2201 break;
2202 case 2: /*SEEK_END*/
2203 bf->l_start += XFS_ISIZE(ip);
2204 break;
2205 default:
2206 return XFS_ERROR(EINVAL);
2207 }
2208
2209 /*
2210 * length of <= 0 for resv/unresv/zero is invalid. length for
2211 * alloc/free is ignored completely and we have no idea what userspace
2212 * might have set it to, so set it to zero to allow range
2213 * checks to pass.
2214 */
2215 switch (cmd) {
2216 case XFS_IOC_ZERO_RANGE:
2217 case XFS_IOC_RESVSP:
2218 case XFS_IOC_RESVSP64:
2219 case XFS_IOC_UNRESVSP:
2220 case XFS_IOC_UNRESVSP64:
2221 if (bf->l_len <= 0)
2222 return XFS_ERROR(EINVAL);
2223 break;
2224 default:
2225 bf->l_len = 0;
2226 break;
2227 }
2228
2229 if (bf->l_start < 0 ||
2230 bf->l_start > mp->m_super->s_maxbytes ||
2231 bf->l_start + bf->l_len < 0 ||
2232 bf->l_start + bf->l_len >= mp->m_super->s_maxbytes)
2233 return XFS_ERROR(EINVAL);
2234
2235 bf->l_whence = 0;
2236
2237 startoffset = bf->l_start;
2238 fsize = XFS_ISIZE(ip);
2239
2240 setprealloc = clrprealloc = 0;
2241 switch (cmd) {
2242 case XFS_IOC_ZERO_RANGE:
2243 error = xfs_zero_file_space(ip, startoffset, bf->l_len,
2244 attr_flags);
2245 if (error)
2246 return error;
2247 setprealloc = 1;
2248 break;
2249
2250 case XFS_IOC_RESVSP:
2251 case XFS_IOC_RESVSP64:
2252 error = xfs_alloc_file_space(ip, startoffset, bf->l_len,
2253 XFS_BMAPI_PREALLOC, attr_flags);
2254 if (error)
2255 return error;
2256 setprealloc = 1;
2257 break;
2258
2259 case XFS_IOC_UNRESVSP:
2260 case XFS_IOC_UNRESVSP64:
2261 if ((error = xfs_free_file_space(ip, startoffset, bf->l_len,
2262 attr_flags)))
2263 return error;
2264 break;
2265
2266 case XFS_IOC_ALLOCSP:
2267 case XFS_IOC_ALLOCSP64:
2268 case XFS_IOC_FREESP:
2269 case XFS_IOC_FREESP64:
2270 /*
2271 * These operations actually do IO when extending the file, but
2272 * the allocation is done seperately to the zeroing that is
2273 * done. This set of operations need to be serialised against
2274 * other IO operations, such as truncate and buffered IO. We
2275 * need to take the IOLOCK here to serialise the allocation and
2276 * zeroing IO to prevent other IOLOCK holders (e.g. getbmap,
2277 * truncate, direct IO) from racing against the transient
2278 * allocated but not written state we can have here.
2279 */
2280 xfs_ilock(ip, XFS_IOLOCK_EXCL);
2281 if (startoffset > fsize) {
2282 error = xfs_alloc_file_space(ip, fsize,
2283 startoffset - fsize, 0,
2284 attr_flags | XFS_ATTR_NOLOCK);
2285 if (error) {
2286 xfs_iunlock(ip, XFS_IOLOCK_EXCL);
2287 break;
2288 }
2289 }
2290
2291 iattr.ia_valid = ATTR_SIZE;
2292 iattr.ia_size = startoffset;
2293
2294 error = xfs_setattr_size(ip, &iattr,
2295 attr_flags | XFS_ATTR_NOLOCK);
2296 xfs_iunlock(ip, XFS_IOLOCK_EXCL);
2297
2298 if (error)
2299 return error;
2300
2301 clrprealloc = 1;
2302 break;
2303
2304 default:
2305 ASSERT(0);
2306 return XFS_ERROR(EINVAL);
2307 }
2308
2309 /*
2310 * update the inode timestamp, mode, and prealloc flag bits
2311 */
2312 tp = xfs_trans_alloc(mp, XFS_TRANS_WRITEID);
2313
2314 if ((error = xfs_trans_reserve(tp, 0, XFS_WRITEID_LOG_RES(mp),
2315 0, 0, 0))) {
2316 /* ASSERT(0); */
2317 xfs_trans_cancel(tp, 0);
2318 return error;
2319 }
2320
2321 xfs_ilock(ip, XFS_ILOCK_EXCL);
2322 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
2323
2324 if ((attr_flags & XFS_ATTR_DMI) == 0) {
2325 ip->i_d.di_mode &= ~S_ISUID;
2326
2327 /*
2328 * Note that we don't have to worry about mandatory
2329 * file locking being disabled here because we only
2330 * clear the S_ISGID bit if the Group execute bit is
2331 * on, but if it was on then mandatory locking wouldn't
2332 * have been enabled.
2333 */
2334 if (ip->i_d.di_mode & S_IXGRP)
2335 ip->i_d.di_mode &= ~S_ISGID;
2336
2337 xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2338 }
2339 if (setprealloc)
2340 ip->i_d.di_flags |= XFS_DIFLAG_PREALLOC;
2341 else if (clrprealloc)
2342 ip->i_d.di_flags &= ~XFS_DIFLAG_PREALLOC;
2343
2344 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
2345 if (attr_flags & XFS_ATTR_SYNC)
2346 xfs_trans_set_sync(tp);
2347 return xfs_trans_commit(tp, 0);
2348}