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