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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (c) 2000-2006 Silicon Graphics, Inc.
4 * All Rights Reserved.
5 */
6#include <linux/iversion.h>
7
8#include "xfs.h"
9#include "xfs_fs.h"
10#include "xfs_shared.h"
11#include "xfs_format.h"
12#include "xfs_log_format.h"
13#include "xfs_trans_resv.h"
14#include "xfs_mount.h"
15#include "xfs_defer.h"
16#include "xfs_inode.h"
17#include "xfs_dir2.h"
18#include "xfs_attr.h"
19#include "xfs_trans_space.h"
20#include "xfs_trans.h"
21#include "xfs_buf_item.h"
22#include "xfs_inode_item.h"
23#include "xfs_iunlink_item.h"
24#include "xfs_ialloc.h"
25#include "xfs_bmap.h"
26#include "xfs_bmap_util.h"
27#include "xfs_errortag.h"
28#include "xfs_error.h"
29#include "xfs_quota.h"
30#include "xfs_filestream.h"
31#include "xfs_trace.h"
32#include "xfs_icache.h"
33#include "xfs_symlink.h"
34#include "xfs_trans_priv.h"
35#include "xfs_log.h"
36#include "xfs_bmap_btree.h"
37#include "xfs_reflink.h"
38#include "xfs_ag.h"
39#include "xfs_log_priv.h"
40#include "xfs_health.h"
41
42struct kmem_cache *xfs_inode_cache;
43
44STATIC int xfs_iunlink(struct xfs_trans *, struct xfs_inode *);
45STATIC int xfs_iunlink_remove(struct xfs_trans *tp, struct xfs_perag *pag,
46 struct xfs_inode *);
47
48/*
49 * helper function to extract extent size hint from inode
50 */
51xfs_extlen_t
52xfs_get_extsz_hint(
53 struct xfs_inode *ip)
54{
55 /*
56 * No point in aligning allocations if we need to COW to actually
57 * write to them.
58 */
59 if (xfs_is_always_cow_inode(ip))
60 return 0;
61 if ((ip->i_diflags & XFS_DIFLAG_EXTSIZE) && ip->i_extsize)
62 return ip->i_extsize;
63 if (XFS_IS_REALTIME_INODE(ip))
64 return ip->i_mount->m_sb.sb_rextsize;
65 return 0;
66}
67
68/*
69 * Helper function to extract CoW extent size hint from inode.
70 * Between the extent size hint and the CoW extent size hint, we
71 * return the greater of the two. If the value is zero (automatic),
72 * use the default size.
73 */
74xfs_extlen_t
75xfs_get_cowextsz_hint(
76 struct xfs_inode *ip)
77{
78 xfs_extlen_t a, b;
79
80 a = 0;
81 if (ip->i_diflags2 & XFS_DIFLAG2_COWEXTSIZE)
82 a = ip->i_cowextsize;
83 b = xfs_get_extsz_hint(ip);
84
85 a = max(a, b);
86 if (a == 0)
87 return XFS_DEFAULT_COWEXTSZ_HINT;
88 return a;
89}
90
91/*
92 * These two are wrapper routines around the xfs_ilock() routine used to
93 * centralize some grungy code. They are used in places that wish to lock the
94 * inode solely for reading the extents. The reason these places can't just
95 * call xfs_ilock(ip, XFS_ILOCK_SHARED) is that the inode lock also guards to
96 * bringing in of the extents from disk for a file in b-tree format. If the
97 * inode is in b-tree format, then we need to lock the inode exclusively until
98 * the extents are read in. Locking it exclusively all the time would limit
99 * our parallelism unnecessarily, though. What we do instead is check to see
100 * if the extents have been read in yet, and only lock the inode exclusively
101 * if they have not.
102 *
103 * The functions return a value which should be given to the corresponding
104 * xfs_iunlock() call.
105 */
106uint
107xfs_ilock_data_map_shared(
108 struct xfs_inode *ip)
109{
110 uint lock_mode = XFS_ILOCK_SHARED;
111
112 if (xfs_need_iread_extents(&ip->i_df))
113 lock_mode = XFS_ILOCK_EXCL;
114 xfs_ilock(ip, lock_mode);
115 return lock_mode;
116}
117
118uint
119xfs_ilock_attr_map_shared(
120 struct xfs_inode *ip)
121{
122 uint lock_mode = XFS_ILOCK_SHARED;
123
124 if (xfs_inode_has_attr_fork(ip) && xfs_need_iread_extents(&ip->i_af))
125 lock_mode = XFS_ILOCK_EXCL;
126 xfs_ilock(ip, lock_mode);
127 return lock_mode;
128}
129
130/*
131 * You can't set both SHARED and EXCL for the same lock,
132 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_MMAPLOCK_SHARED,
133 * XFS_MMAPLOCK_EXCL, XFS_ILOCK_SHARED, XFS_ILOCK_EXCL are valid values
134 * to set in lock_flags.
135 */
136static inline void
137xfs_lock_flags_assert(
138 uint lock_flags)
139{
140 ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
141 (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
142 ASSERT((lock_flags & (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)) !=
143 (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL));
144 ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
145 (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
146 ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0);
147 ASSERT(lock_flags != 0);
148}
149
150/*
151 * In addition to i_rwsem in the VFS inode, the xfs inode contains 2
152 * multi-reader locks: invalidate_lock and the i_lock. This routine allows
153 * various combinations of the locks to be obtained.
154 *
155 * The 3 locks should always be ordered so that the IO lock is obtained first,
156 * the mmap lock second and the ilock last in order to prevent deadlock.
157 *
158 * Basic locking order:
159 *
160 * i_rwsem -> invalidate_lock -> page_lock -> i_ilock
161 *
162 * mmap_lock locking order:
163 *
164 * i_rwsem -> page lock -> mmap_lock
165 * mmap_lock -> invalidate_lock -> page_lock
166 *
167 * The difference in mmap_lock locking order mean that we cannot hold the
168 * invalidate_lock over syscall based read(2)/write(2) based IO. These IO paths
169 * can fault in pages during copy in/out (for buffered IO) or require the
170 * mmap_lock in get_user_pages() to map the user pages into the kernel address
171 * space for direct IO. Similarly the i_rwsem cannot be taken inside a page
172 * fault because page faults already hold the mmap_lock.
173 *
174 * Hence to serialise fully against both syscall and mmap based IO, we need to
175 * take both the i_rwsem and the invalidate_lock. These locks should *only* be
176 * both taken in places where we need to invalidate the page cache in a race
177 * free manner (e.g. truncate, hole punch and other extent manipulation
178 * functions).
179 */
180void
181xfs_ilock(
182 xfs_inode_t *ip,
183 uint lock_flags)
184{
185 trace_xfs_ilock(ip, lock_flags, _RET_IP_);
186
187 xfs_lock_flags_assert(lock_flags);
188
189 if (lock_flags & XFS_IOLOCK_EXCL) {
190 down_write_nested(&VFS_I(ip)->i_rwsem,
191 XFS_IOLOCK_DEP(lock_flags));
192 } else if (lock_flags & XFS_IOLOCK_SHARED) {
193 down_read_nested(&VFS_I(ip)->i_rwsem,
194 XFS_IOLOCK_DEP(lock_flags));
195 }
196
197 if (lock_flags & XFS_MMAPLOCK_EXCL) {
198 down_write_nested(&VFS_I(ip)->i_mapping->invalidate_lock,
199 XFS_MMAPLOCK_DEP(lock_flags));
200 } else if (lock_flags & XFS_MMAPLOCK_SHARED) {
201 down_read_nested(&VFS_I(ip)->i_mapping->invalidate_lock,
202 XFS_MMAPLOCK_DEP(lock_flags));
203 }
204
205 if (lock_flags & XFS_ILOCK_EXCL)
206 down_write_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
207 else if (lock_flags & XFS_ILOCK_SHARED)
208 down_read_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
209}
210
211/*
212 * This is just like xfs_ilock(), except that the caller
213 * is guaranteed not to sleep. It returns 1 if it gets
214 * the requested locks and 0 otherwise. If the IO lock is
215 * obtained but the inode lock cannot be, then the IO lock
216 * is dropped before returning.
217 *
218 * ip -- the inode being locked
219 * lock_flags -- this parameter indicates the inode's locks to be
220 * to be locked. See the comment for xfs_ilock() for a list
221 * of valid values.
222 */
223int
224xfs_ilock_nowait(
225 xfs_inode_t *ip,
226 uint lock_flags)
227{
228 trace_xfs_ilock_nowait(ip, lock_flags, _RET_IP_);
229
230 xfs_lock_flags_assert(lock_flags);
231
232 if (lock_flags & XFS_IOLOCK_EXCL) {
233 if (!down_write_trylock(&VFS_I(ip)->i_rwsem))
234 goto out;
235 } else if (lock_flags & XFS_IOLOCK_SHARED) {
236 if (!down_read_trylock(&VFS_I(ip)->i_rwsem))
237 goto out;
238 }
239
240 if (lock_flags & XFS_MMAPLOCK_EXCL) {
241 if (!down_write_trylock(&VFS_I(ip)->i_mapping->invalidate_lock))
242 goto out_undo_iolock;
243 } else if (lock_flags & XFS_MMAPLOCK_SHARED) {
244 if (!down_read_trylock(&VFS_I(ip)->i_mapping->invalidate_lock))
245 goto out_undo_iolock;
246 }
247
248 if (lock_flags & XFS_ILOCK_EXCL) {
249 if (!down_write_trylock(&ip->i_lock))
250 goto out_undo_mmaplock;
251 } else if (lock_flags & XFS_ILOCK_SHARED) {
252 if (!down_read_trylock(&ip->i_lock))
253 goto out_undo_mmaplock;
254 }
255 return 1;
256
257out_undo_mmaplock:
258 if (lock_flags & XFS_MMAPLOCK_EXCL)
259 up_write(&VFS_I(ip)->i_mapping->invalidate_lock);
260 else if (lock_flags & XFS_MMAPLOCK_SHARED)
261 up_read(&VFS_I(ip)->i_mapping->invalidate_lock);
262out_undo_iolock:
263 if (lock_flags & XFS_IOLOCK_EXCL)
264 up_write(&VFS_I(ip)->i_rwsem);
265 else if (lock_flags & XFS_IOLOCK_SHARED)
266 up_read(&VFS_I(ip)->i_rwsem);
267out:
268 return 0;
269}
270
271/*
272 * xfs_iunlock() is used to drop the inode locks acquired with
273 * xfs_ilock() and xfs_ilock_nowait(). The caller must pass
274 * in the flags given to xfs_ilock() or xfs_ilock_nowait() so
275 * that we know which locks to drop.
276 *
277 * ip -- the inode being unlocked
278 * lock_flags -- this parameter indicates the inode's locks to be
279 * to be unlocked. See the comment for xfs_ilock() for a list
280 * of valid values for this parameter.
281 *
282 */
283void
284xfs_iunlock(
285 xfs_inode_t *ip,
286 uint lock_flags)
287{
288 xfs_lock_flags_assert(lock_flags);
289
290 if (lock_flags & XFS_IOLOCK_EXCL)
291 up_write(&VFS_I(ip)->i_rwsem);
292 else if (lock_flags & XFS_IOLOCK_SHARED)
293 up_read(&VFS_I(ip)->i_rwsem);
294
295 if (lock_flags & XFS_MMAPLOCK_EXCL)
296 up_write(&VFS_I(ip)->i_mapping->invalidate_lock);
297 else if (lock_flags & XFS_MMAPLOCK_SHARED)
298 up_read(&VFS_I(ip)->i_mapping->invalidate_lock);
299
300 if (lock_flags & XFS_ILOCK_EXCL)
301 up_write(&ip->i_lock);
302 else if (lock_flags & XFS_ILOCK_SHARED)
303 up_read(&ip->i_lock);
304
305 trace_xfs_iunlock(ip, lock_flags, _RET_IP_);
306}
307
308/*
309 * give up write locks. the i/o lock cannot be held nested
310 * if it is being demoted.
311 */
312void
313xfs_ilock_demote(
314 xfs_inode_t *ip,
315 uint lock_flags)
316{
317 ASSERT(lock_flags & (XFS_IOLOCK_EXCL|XFS_MMAPLOCK_EXCL|XFS_ILOCK_EXCL));
318 ASSERT((lock_flags &
319 ~(XFS_IOLOCK_EXCL|XFS_MMAPLOCK_EXCL|XFS_ILOCK_EXCL)) == 0);
320
321 if (lock_flags & XFS_ILOCK_EXCL)
322 downgrade_write(&ip->i_lock);
323 if (lock_flags & XFS_MMAPLOCK_EXCL)
324 downgrade_write(&VFS_I(ip)->i_mapping->invalidate_lock);
325 if (lock_flags & XFS_IOLOCK_EXCL)
326 downgrade_write(&VFS_I(ip)->i_rwsem);
327
328 trace_xfs_ilock_demote(ip, lock_flags, _RET_IP_);
329}
330
331void
332xfs_assert_ilocked(
333 struct xfs_inode *ip,
334 uint lock_flags)
335{
336 /*
337 * Sometimes we assert the ILOCK is held exclusively, but we're in
338 * a workqueue, so lockdep doesn't know we're the owner.
339 */
340 if (lock_flags & XFS_ILOCK_SHARED)
341 rwsem_assert_held(&ip->i_lock);
342 else if (lock_flags & XFS_ILOCK_EXCL)
343 rwsem_assert_held_write_nolockdep(&ip->i_lock);
344
345 if (lock_flags & XFS_MMAPLOCK_SHARED)
346 rwsem_assert_held(&VFS_I(ip)->i_mapping->invalidate_lock);
347 else if (lock_flags & XFS_MMAPLOCK_EXCL)
348 rwsem_assert_held_write(&VFS_I(ip)->i_mapping->invalidate_lock);
349
350 if (lock_flags & XFS_IOLOCK_SHARED)
351 rwsem_assert_held(&VFS_I(ip)->i_rwsem);
352 else if (lock_flags & XFS_IOLOCK_EXCL)
353 rwsem_assert_held_write(&VFS_I(ip)->i_rwsem);
354}
355
356/*
357 * xfs_lockdep_subclass_ok() is only used in an ASSERT, so is only called when
358 * DEBUG or XFS_WARN is set. And MAX_LOCKDEP_SUBCLASSES is then only defined
359 * when CONFIG_LOCKDEP is set. Hence the complex define below to avoid build
360 * errors and warnings.
361 */
362#if (defined(DEBUG) || defined(XFS_WARN)) && defined(CONFIG_LOCKDEP)
363static bool
364xfs_lockdep_subclass_ok(
365 int subclass)
366{
367 return subclass < MAX_LOCKDEP_SUBCLASSES;
368}
369#else
370#define xfs_lockdep_subclass_ok(subclass) (true)
371#endif
372
373/*
374 * Bump the subclass so xfs_lock_inodes() acquires each lock with a different
375 * value. This can be called for any type of inode lock combination, including
376 * parent locking. Care must be taken to ensure we don't overrun the subclass
377 * storage fields in the class mask we build.
378 */
379static inline uint
380xfs_lock_inumorder(
381 uint lock_mode,
382 uint subclass)
383{
384 uint class = 0;
385
386 ASSERT(!(lock_mode & (XFS_ILOCK_PARENT | XFS_ILOCK_RTBITMAP |
387 XFS_ILOCK_RTSUM)));
388 ASSERT(xfs_lockdep_subclass_ok(subclass));
389
390 if (lock_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)) {
391 ASSERT(subclass <= XFS_IOLOCK_MAX_SUBCLASS);
392 class += subclass << XFS_IOLOCK_SHIFT;
393 }
394
395 if (lock_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) {
396 ASSERT(subclass <= XFS_MMAPLOCK_MAX_SUBCLASS);
397 class += subclass << XFS_MMAPLOCK_SHIFT;
398 }
399
400 if (lock_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)) {
401 ASSERT(subclass <= XFS_ILOCK_MAX_SUBCLASS);
402 class += subclass << XFS_ILOCK_SHIFT;
403 }
404
405 return (lock_mode & ~XFS_LOCK_SUBCLASS_MASK) | class;
406}
407
408/*
409 * The following routine will lock n inodes in exclusive mode. We assume the
410 * caller calls us with the inodes in i_ino order.
411 *
412 * We need to detect deadlock where an inode that we lock is in the AIL and we
413 * start waiting for another inode that is locked by a thread in a long running
414 * transaction (such as truncate). This can result in deadlock since the long
415 * running trans might need to wait for the inode we just locked in order to
416 * push the tail and free space in the log.
417 *
418 * xfs_lock_inodes() can only be used to lock one type of lock at a time -
419 * the iolock, the mmaplock or the ilock, but not more than one at a time. If we
420 * lock more than one at a time, lockdep will report false positives saying we
421 * have violated locking orders.
422 */
423static void
424xfs_lock_inodes(
425 struct xfs_inode **ips,
426 int inodes,
427 uint lock_mode)
428{
429 int attempts = 0;
430 uint i;
431 int j;
432 bool try_lock;
433 struct xfs_log_item *lp;
434
435 /*
436 * Currently supports between 2 and 5 inodes with exclusive locking. We
437 * support an arbitrary depth of locking here, but absolute limits on
438 * inodes depend on the type of locking and the limits placed by
439 * lockdep annotations in xfs_lock_inumorder. These are all checked by
440 * the asserts.
441 */
442 ASSERT(ips && inodes >= 2 && inodes <= 5);
443 ASSERT(lock_mode & (XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL |
444 XFS_ILOCK_EXCL));
445 ASSERT(!(lock_mode & (XFS_IOLOCK_SHARED | XFS_MMAPLOCK_SHARED |
446 XFS_ILOCK_SHARED)));
447 ASSERT(!(lock_mode & XFS_MMAPLOCK_EXCL) ||
448 inodes <= XFS_MMAPLOCK_MAX_SUBCLASS + 1);
449 ASSERT(!(lock_mode & XFS_ILOCK_EXCL) ||
450 inodes <= XFS_ILOCK_MAX_SUBCLASS + 1);
451
452 if (lock_mode & XFS_IOLOCK_EXCL) {
453 ASSERT(!(lock_mode & (XFS_MMAPLOCK_EXCL | XFS_ILOCK_EXCL)));
454 } else if (lock_mode & XFS_MMAPLOCK_EXCL)
455 ASSERT(!(lock_mode & XFS_ILOCK_EXCL));
456
457again:
458 try_lock = false;
459 i = 0;
460 for (; i < inodes; i++) {
461 ASSERT(ips[i]);
462
463 if (i && (ips[i] == ips[i - 1])) /* Already locked */
464 continue;
465
466 /*
467 * If try_lock is not set yet, make sure all locked inodes are
468 * not in the AIL. If any are, set try_lock to be used later.
469 */
470 if (!try_lock) {
471 for (j = (i - 1); j >= 0 && !try_lock; j--) {
472 lp = &ips[j]->i_itemp->ili_item;
473 if (lp && test_bit(XFS_LI_IN_AIL, &lp->li_flags))
474 try_lock = true;
475 }
476 }
477
478 /*
479 * If any of the previous locks we have locked is in the AIL,
480 * we must TRY to get the second and subsequent locks. If
481 * we can't get any, we must release all we have
482 * and try again.
483 */
484 if (!try_lock) {
485 xfs_ilock(ips[i], xfs_lock_inumorder(lock_mode, i));
486 continue;
487 }
488
489 /* try_lock means we have an inode locked that is in the AIL. */
490 ASSERT(i != 0);
491 if (xfs_ilock_nowait(ips[i], xfs_lock_inumorder(lock_mode, i)))
492 continue;
493
494 /*
495 * Unlock all previous guys and try again. xfs_iunlock will try
496 * to push the tail if the inode is in the AIL.
497 */
498 attempts++;
499 for (j = i - 1; j >= 0; j--) {
500 /*
501 * Check to see if we've already unlocked this one. Not
502 * the first one going back, and the inode ptr is the
503 * same.
504 */
505 if (j != (i - 1) && ips[j] == ips[j + 1])
506 continue;
507
508 xfs_iunlock(ips[j], lock_mode);
509 }
510
511 if ((attempts % 5) == 0) {
512 delay(1); /* Don't just spin the CPU */
513 }
514 goto again;
515 }
516}
517
518/*
519 * xfs_lock_two_inodes() can only be used to lock ilock. The iolock and
520 * mmaplock must be double-locked separately since we use i_rwsem and
521 * invalidate_lock for that. We now support taking one lock EXCL and the
522 * other SHARED.
523 */
524void
525xfs_lock_two_inodes(
526 struct xfs_inode *ip0,
527 uint ip0_mode,
528 struct xfs_inode *ip1,
529 uint ip1_mode)
530{
531 int attempts = 0;
532 struct xfs_log_item *lp;
533
534 ASSERT(hweight32(ip0_mode) == 1);
535 ASSERT(hweight32(ip1_mode) == 1);
536 ASSERT(!(ip0_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)));
537 ASSERT(!(ip1_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)));
538 ASSERT(!(ip0_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)));
539 ASSERT(!(ip1_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)));
540 ASSERT(ip0->i_ino != ip1->i_ino);
541
542 if (ip0->i_ino > ip1->i_ino) {
543 swap(ip0, ip1);
544 swap(ip0_mode, ip1_mode);
545 }
546
547 again:
548 xfs_ilock(ip0, xfs_lock_inumorder(ip0_mode, 0));
549
550 /*
551 * If the first lock we have locked is in the AIL, we must TRY to get
552 * the second lock. If we can't get it, we must release the first one
553 * and try again.
554 */
555 lp = &ip0->i_itemp->ili_item;
556 if (lp && test_bit(XFS_LI_IN_AIL, &lp->li_flags)) {
557 if (!xfs_ilock_nowait(ip1, xfs_lock_inumorder(ip1_mode, 1))) {
558 xfs_iunlock(ip0, ip0_mode);
559 if ((++attempts % 5) == 0)
560 delay(1); /* Don't just spin the CPU */
561 goto again;
562 }
563 } else {
564 xfs_ilock(ip1, xfs_lock_inumorder(ip1_mode, 1));
565 }
566}
567
568uint
569xfs_ip2xflags(
570 struct xfs_inode *ip)
571{
572 uint flags = 0;
573
574 if (ip->i_diflags & XFS_DIFLAG_ANY) {
575 if (ip->i_diflags & XFS_DIFLAG_REALTIME)
576 flags |= FS_XFLAG_REALTIME;
577 if (ip->i_diflags & XFS_DIFLAG_PREALLOC)
578 flags |= FS_XFLAG_PREALLOC;
579 if (ip->i_diflags & XFS_DIFLAG_IMMUTABLE)
580 flags |= FS_XFLAG_IMMUTABLE;
581 if (ip->i_diflags & XFS_DIFLAG_APPEND)
582 flags |= FS_XFLAG_APPEND;
583 if (ip->i_diflags & XFS_DIFLAG_SYNC)
584 flags |= FS_XFLAG_SYNC;
585 if (ip->i_diflags & XFS_DIFLAG_NOATIME)
586 flags |= FS_XFLAG_NOATIME;
587 if (ip->i_diflags & XFS_DIFLAG_NODUMP)
588 flags |= FS_XFLAG_NODUMP;
589 if (ip->i_diflags & XFS_DIFLAG_RTINHERIT)
590 flags |= FS_XFLAG_RTINHERIT;
591 if (ip->i_diflags & XFS_DIFLAG_PROJINHERIT)
592 flags |= FS_XFLAG_PROJINHERIT;
593 if (ip->i_diflags & XFS_DIFLAG_NOSYMLINKS)
594 flags |= FS_XFLAG_NOSYMLINKS;
595 if (ip->i_diflags & XFS_DIFLAG_EXTSIZE)
596 flags |= FS_XFLAG_EXTSIZE;
597 if (ip->i_diflags & XFS_DIFLAG_EXTSZINHERIT)
598 flags |= FS_XFLAG_EXTSZINHERIT;
599 if (ip->i_diflags & XFS_DIFLAG_NODEFRAG)
600 flags |= FS_XFLAG_NODEFRAG;
601 if (ip->i_diflags & XFS_DIFLAG_FILESTREAM)
602 flags |= FS_XFLAG_FILESTREAM;
603 }
604
605 if (ip->i_diflags2 & XFS_DIFLAG2_ANY) {
606 if (ip->i_diflags2 & XFS_DIFLAG2_DAX)
607 flags |= FS_XFLAG_DAX;
608 if (ip->i_diflags2 & XFS_DIFLAG2_COWEXTSIZE)
609 flags |= FS_XFLAG_COWEXTSIZE;
610 }
611
612 if (xfs_inode_has_attr_fork(ip))
613 flags |= FS_XFLAG_HASATTR;
614 return flags;
615}
616
617/*
618 * Lookups up an inode from "name". If ci_name is not NULL, then a CI match
619 * is allowed, otherwise it has to be an exact match. If a CI match is found,
620 * ci_name->name will point to a the actual name (caller must free) or
621 * will be set to NULL if an exact match is found.
622 */
623int
624xfs_lookup(
625 struct xfs_inode *dp,
626 const struct xfs_name *name,
627 struct xfs_inode **ipp,
628 struct xfs_name *ci_name)
629{
630 xfs_ino_t inum;
631 int error;
632
633 trace_xfs_lookup(dp, name);
634
635 if (xfs_is_shutdown(dp->i_mount))
636 return -EIO;
637 if (xfs_ifork_zapped(dp, XFS_DATA_FORK))
638 return -EIO;
639
640 error = xfs_dir_lookup(NULL, dp, name, &inum, ci_name);
641 if (error)
642 goto out_unlock;
643
644 error = xfs_iget(dp->i_mount, NULL, inum, 0, 0, ipp);
645 if (error)
646 goto out_free_name;
647
648 return 0;
649
650out_free_name:
651 if (ci_name)
652 kfree(ci_name->name);
653out_unlock:
654 *ipp = NULL;
655 return error;
656}
657
658/* Propagate di_flags from a parent inode to a child inode. */
659static void
660xfs_inode_inherit_flags(
661 struct xfs_inode *ip,
662 const struct xfs_inode *pip)
663{
664 unsigned int di_flags = 0;
665 xfs_failaddr_t failaddr;
666 umode_t mode = VFS_I(ip)->i_mode;
667
668 if (S_ISDIR(mode)) {
669 if (pip->i_diflags & XFS_DIFLAG_RTINHERIT)
670 di_flags |= XFS_DIFLAG_RTINHERIT;
671 if (pip->i_diflags & XFS_DIFLAG_EXTSZINHERIT) {
672 di_flags |= XFS_DIFLAG_EXTSZINHERIT;
673 ip->i_extsize = pip->i_extsize;
674 }
675 if (pip->i_diflags & XFS_DIFLAG_PROJINHERIT)
676 di_flags |= XFS_DIFLAG_PROJINHERIT;
677 } else if (S_ISREG(mode)) {
678 if ((pip->i_diflags & XFS_DIFLAG_RTINHERIT) &&
679 xfs_has_realtime(ip->i_mount))
680 di_flags |= XFS_DIFLAG_REALTIME;
681 if (pip->i_diflags & XFS_DIFLAG_EXTSZINHERIT) {
682 di_flags |= XFS_DIFLAG_EXTSIZE;
683 ip->i_extsize = pip->i_extsize;
684 }
685 }
686 if ((pip->i_diflags & XFS_DIFLAG_NOATIME) &&
687 xfs_inherit_noatime)
688 di_flags |= XFS_DIFLAG_NOATIME;
689 if ((pip->i_diflags & XFS_DIFLAG_NODUMP) &&
690 xfs_inherit_nodump)
691 di_flags |= XFS_DIFLAG_NODUMP;
692 if ((pip->i_diflags & XFS_DIFLAG_SYNC) &&
693 xfs_inherit_sync)
694 di_flags |= XFS_DIFLAG_SYNC;
695 if ((pip->i_diflags & XFS_DIFLAG_NOSYMLINKS) &&
696 xfs_inherit_nosymlinks)
697 di_flags |= XFS_DIFLAG_NOSYMLINKS;
698 if ((pip->i_diflags & XFS_DIFLAG_NODEFRAG) &&
699 xfs_inherit_nodefrag)
700 di_flags |= XFS_DIFLAG_NODEFRAG;
701 if (pip->i_diflags & XFS_DIFLAG_FILESTREAM)
702 di_flags |= XFS_DIFLAG_FILESTREAM;
703
704 ip->i_diflags |= di_flags;
705
706 /*
707 * Inode verifiers on older kernels only check that the extent size
708 * hint is an integer multiple of the rt extent size on realtime files.
709 * They did not check the hint alignment on a directory with both
710 * rtinherit and extszinherit flags set. If the misaligned hint is
711 * propagated from a directory into a new realtime file, new file
712 * allocations will fail due to math errors in the rt allocator and/or
713 * trip the verifiers. Validate the hint settings in the new file so
714 * that we don't let broken hints propagate.
715 */
716 failaddr = xfs_inode_validate_extsize(ip->i_mount, ip->i_extsize,
717 VFS_I(ip)->i_mode, ip->i_diflags);
718 if (failaddr) {
719 ip->i_diflags &= ~(XFS_DIFLAG_EXTSIZE |
720 XFS_DIFLAG_EXTSZINHERIT);
721 ip->i_extsize = 0;
722 }
723}
724
725/* Propagate di_flags2 from a parent inode to a child inode. */
726static void
727xfs_inode_inherit_flags2(
728 struct xfs_inode *ip,
729 const struct xfs_inode *pip)
730{
731 xfs_failaddr_t failaddr;
732
733 if (pip->i_diflags2 & XFS_DIFLAG2_COWEXTSIZE) {
734 ip->i_diflags2 |= XFS_DIFLAG2_COWEXTSIZE;
735 ip->i_cowextsize = pip->i_cowextsize;
736 }
737 if (pip->i_diflags2 & XFS_DIFLAG2_DAX)
738 ip->i_diflags2 |= XFS_DIFLAG2_DAX;
739
740 /* Don't let invalid cowextsize hints propagate. */
741 failaddr = xfs_inode_validate_cowextsize(ip->i_mount, ip->i_cowextsize,
742 VFS_I(ip)->i_mode, ip->i_diflags, ip->i_diflags2);
743 if (failaddr) {
744 ip->i_diflags2 &= ~XFS_DIFLAG2_COWEXTSIZE;
745 ip->i_cowextsize = 0;
746 }
747}
748
749/*
750 * Initialise a newly allocated inode and return the in-core inode to the
751 * caller locked exclusively.
752 */
753int
754xfs_init_new_inode(
755 struct mnt_idmap *idmap,
756 struct xfs_trans *tp,
757 struct xfs_inode *pip,
758 xfs_ino_t ino,
759 umode_t mode,
760 xfs_nlink_t nlink,
761 dev_t rdev,
762 prid_t prid,
763 bool init_xattrs,
764 struct xfs_inode **ipp)
765{
766 struct inode *dir = pip ? VFS_I(pip) : NULL;
767 struct xfs_mount *mp = tp->t_mountp;
768 struct xfs_inode *ip;
769 unsigned int flags;
770 int error;
771 struct timespec64 tv;
772 struct inode *inode;
773
774 /*
775 * Protect against obviously corrupt allocation btree records. Later
776 * xfs_iget checks will catch re-allocation of other active in-memory
777 * and on-disk inodes. If we don't catch reallocating the parent inode
778 * here we will deadlock in xfs_iget() so we have to do these checks
779 * first.
780 */
781 if ((pip && ino == pip->i_ino) || !xfs_verify_dir_ino(mp, ino)) {
782 xfs_alert(mp, "Allocated a known in-use inode 0x%llx!", ino);
783 xfs_agno_mark_sick(mp, XFS_INO_TO_AGNO(mp, ino),
784 XFS_SICK_AG_INOBT);
785 return -EFSCORRUPTED;
786 }
787
788 /*
789 * Get the in-core inode with the lock held exclusively to prevent
790 * others from looking at until we're done.
791 */
792 error = xfs_iget(mp, tp, ino, XFS_IGET_CREATE, XFS_ILOCK_EXCL, &ip);
793 if (error)
794 return error;
795
796 ASSERT(ip != NULL);
797 inode = VFS_I(ip);
798 set_nlink(inode, nlink);
799 inode->i_rdev = rdev;
800 ip->i_projid = prid;
801
802 if (dir && !(dir->i_mode & S_ISGID) && xfs_has_grpid(mp)) {
803 inode_fsuid_set(inode, idmap);
804 inode->i_gid = dir->i_gid;
805 inode->i_mode = mode;
806 } else {
807 inode_init_owner(idmap, inode, dir, mode);
808 }
809
810 /*
811 * If the group ID of the new file does not match the effective group
812 * ID or one of the supplementary group IDs, the S_ISGID bit is cleared
813 * (and only if the irix_sgid_inherit compatibility variable is set).
814 */
815 if (irix_sgid_inherit && (inode->i_mode & S_ISGID) &&
816 !vfsgid_in_group_p(i_gid_into_vfsgid(idmap, inode)))
817 inode->i_mode &= ~S_ISGID;
818
819 ip->i_disk_size = 0;
820 ip->i_df.if_nextents = 0;
821 ASSERT(ip->i_nblocks == 0);
822
823 tv = inode_set_ctime_current(inode);
824 inode_set_mtime_to_ts(inode, tv);
825 inode_set_atime_to_ts(inode, tv);
826
827 ip->i_extsize = 0;
828 ip->i_diflags = 0;
829
830 if (xfs_has_v3inodes(mp)) {
831 inode_set_iversion(inode, 1);
832 ip->i_cowextsize = 0;
833 ip->i_crtime = tv;
834 }
835
836 flags = XFS_ILOG_CORE;
837 switch (mode & S_IFMT) {
838 case S_IFIFO:
839 case S_IFCHR:
840 case S_IFBLK:
841 case S_IFSOCK:
842 ip->i_df.if_format = XFS_DINODE_FMT_DEV;
843 flags |= XFS_ILOG_DEV;
844 break;
845 case S_IFREG:
846 case S_IFDIR:
847 if (pip && (pip->i_diflags & XFS_DIFLAG_ANY))
848 xfs_inode_inherit_flags(ip, pip);
849 if (pip && (pip->i_diflags2 & XFS_DIFLAG2_ANY))
850 xfs_inode_inherit_flags2(ip, pip);
851 fallthrough;
852 case S_IFLNK:
853 ip->i_df.if_format = XFS_DINODE_FMT_EXTENTS;
854 ip->i_df.if_bytes = 0;
855 ip->i_df.if_data = NULL;
856 break;
857 default:
858 ASSERT(0);
859 }
860
861 /*
862 * If we need to create attributes immediately after allocating the
863 * inode, initialise an empty attribute fork right now. We use the
864 * default fork offset for attributes here as we don't know exactly what
865 * size or how many attributes we might be adding. We can do this
866 * safely here because we know the data fork is completely empty and
867 * this saves us from needing to run a separate transaction to set the
868 * fork offset in the immediate future.
869 */
870 if (init_xattrs && xfs_has_attr(mp)) {
871 ip->i_forkoff = xfs_default_attroffset(ip) >> 3;
872 xfs_ifork_init_attr(ip, XFS_DINODE_FMT_EXTENTS, 0);
873 }
874
875 /*
876 * Log the new values stuffed into the inode.
877 */
878 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
879 xfs_trans_log_inode(tp, ip, flags);
880
881 /* now that we have an i_mode we can setup the inode structure */
882 xfs_setup_inode(ip);
883
884 *ipp = ip;
885 return 0;
886}
887
888/*
889 * Decrement the link count on an inode & log the change. If this causes the
890 * link count to go to zero, move the inode to AGI unlinked list so that it can
891 * be freed when the last active reference goes away via xfs_inactive().
892 */
893static int /* error */
894xfs_droplink(
895 xfs_trans_t *tp,
896 xfs_inode_t *ip)
897{
898 if (VFS_I(ip)->i_nlink == 0) {
899 xfs_alert(ip->i_mount,
900 "%s: Attempt to drop inode (%llu) with nlink zero.",
901 __func__, ip->i_ino);
902 return -EFSCORRUPTED;
903 }
904
905 xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
906
907 drop_nlink(VFS_I(ip));
908 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
909
910 if (VFS_I(ip)->i_nlink)
911 return 0;
912
913 return xfs_iunlink(tp, ip);
914}
915
916/*
917 * Increment the link count on an inode & log the change.
918 */
919static void
920xfs_bumplink(
921 xfs_trans_t *tp,
922 xfs_inode_t *ip)
923{
924 xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
925
926 inc_nlink(VFS_I(ip));
927 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
928}
929
930#ifdef CONFIG_XFS_LIVE_HOOKS
931/*
932 * Use a static key here to reduce the overhead of directory live update hooks.
933 * If the compiler supports jump labels, the static branch will be replaced by
934 * a nop sled when there are no hook users. Online fsck is currently the only
935 * caller, so this is a reasonable tradeoff.
936 *
937 * Note: Patching the kernel code requires taking the cpu hotplug lock. Other
938 * parts of the kernel allocate memory with that lock held, which means that
939 * XFS callers cannot hold any locks that might be used by memory reclaim or
940 * writeback when calling the static_branch_{inc,dec} functions.
941 */
942DEFINE_STATIC_XFS_HOOK_SWITCH(xfs_dir_hooks_switch);
943
944void
945xfs_dir_hook_disable(void)
946{
947 xfs_hooks_switch_off(&xfs_dir_hooks_switch);
948}
949
950void
951xfs_dir_hook_enable(void)
952{
953 xfs_hooks_switch_on(&xfs_dir_hooks_switch);
954}
955
956/* Call hooks for a directory update relating to a child dirent update. */
957inline void
958xfs_dir_update_hook(
959 struct xfs_inode *dp,
960 struct xfs_inode *ip,
961 int delta,
962 const struct xfs_name *name)
963{
964 if (xfs_hooks_switched_on(&xfs_dir_hooks_switch)) {
965 struct xfs_dir_update_params p = {
966 .dp = dp,
967 .ip = ip,
968 .delta = delta,
969 .name = name,
970 };
971 struct xfs_mount *mp = ip->i_mount;
972
973 xfs_hooks_call(&mp->m_dir_update_hooks, 0, &p);
974 }
975}
976
977/* Call the specified function during a directory update. */
978int
979xfs_dir_hook_add(
980 struct xfs_mount *mp,
981 struct xfs_dir_hook *hook)
982{
983 return xfs_hooks_add(&mp->m_dir_update_hooks, &hook->dirent_hook);
984}
985
986/* Stop calling the specified function during a directory update. */
987void
988xfs_dir_hook_del(
989 struct xfs_mount *mp,
990 struct xfs_dir_hook *hook)
991{
992 xfs_hooks_del(&mp->m_dir_update_hooks, &hook->dirent_hook);
993}
994
995/* Configure directory update hook functions. */
996void
997xfs_dir_hook_setup(
998 struct xfs_dir_hook *hook,
999 notifier_fn_t mod_fn)
1000{
1001 xfs_hook_setup(&hook->dirent_hook, mod_fn);
1002}
1003#endif /* CONFIG_XFS_LIVE_HOOKS */
1004
1005int
1006xfs_create(
1007 struct mnt_idmap *idmap,
1008 xfs_inode_t *dp,
1009 struct xfs_name *name,
1010 umode_t mode,
1011 dev_t rdev,
1012 bool init_xattrs,
1013 xfs_inode_t **ipp)
1014{
1015 int is_dir = S_ISDIR(mode);
1016 struct xfs_mount *mp = dp->i_mount;
1017 struct xfs_inode *ip = NULL;
1018 struct xfs_trans *tp = NULL;
1019 int error;
1020 bool unlock_dp_on_error = false;
1021 prid_t prid;
1022 struct xfs_dquot *udqp = NULL;
1023 struct xfs_dquot *gdqp = NULL;
1024 struct xfs_dquot *pdqp = NULL;
1025 struct xfs_trans_res *tres;
1026 uint resblks;
1027 xfs_ino_t ino;
1028
1029 trace_xfs_create(dp, name);
1030
1031 if (xfs_is_shutdown(mp))
1032 return -EIO;
1033 if (xfs_ifork_zapped(dp, XFS_DATA_FORK))
1034 return -EIO;
1035
1036 prid = xfs_get_initial_prid(dp);
1037
1038 /*
1039 * Make sure that we have allocated dquot(s) on disk.
1040 */
1041 error = xfs_qm_vop_dqalloc(dp, mapped_fsuid(idmap, &init_user_ns),
1042 mapped_fsgid(idmap, &init_user_ns), prid,
1043 XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
1044 &udqp, &gdqp, &pdqp);
1045 if (error)
1046 return error;
1047
1048 if (is_dir) {
1049 resblks = XFS_MKDIR_SPACE_RES(mp, name->len);
1050 tres = &M_RES(mp)->tr_mkdir;
1051 } else {
1052 resblks = XFS_CREATE_SPACE_RES(mp, name->len);
1053 tres = &M_RES(mp)->tr_create;
1054 }
1055
1056 /*
1057 * Initially assume that the file does not exist and
1058 * reserve the resources for that case. If that is not
1059 * the case we'll drop the one we have and get a more
1060 * appropriate transaction later.
1061 */
1062 error = xfs_trans_alloc_icreate(mp, tres, udqp, gdqp, pdqp, resblks,
1063 &tp);
1064 if (error == -ENOSPC) {
1065 /* flush outstanding delalloc blocks and retry */
1066 xfs_flush_inodes(mp);
1067 error = xfs_trans_alloc_icreate(mp, tres, udqp, gdqp, pdqp,
1068 resblks, &tp);
1069 }
1070 if (error)
1071 goto out_release_dquots;
1072
1073 xfs_ilock(dp, XFS_ILOCK_EXCL | XFS_ILOCK_PARENT);
1074 unlock_dp_on_error = true;
1075
1076 /*
1077 * A newly created regular or special file just has one directory
1078 * entry pointing to them, but a directory also the "." entry
1079 * pointing to itself.
1080 */
1081 error = xfs_dialloc(&tp, dp->i_ino, mode, &ino);
1082 if (!error)
1083 error = xfs_init_new_inode(idmap, tp, dp, ino, mode,
1084 is_dir ? 2 : 1, rdev, prid, init_xattrs, &ip);
1085 if (error)
1086 goto out_trans_cancel;
1087
1088 /*
1089 * Now we join the directory inode to the transaction. We do not do it
1090 * earlier because xfs_dialloc might commit the previous transaction
1091 * (and release all the locks). An error from here on will result in
1092 * the transaction cancel unlocking dp so don't do it explicitly in the
1093 * error path.
1094 */
1095 xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
1096 unlock_dp_on_error = false;
1097
1098 error = xfs_dir_createname(tp, dp, name, ip->i_ino,
1099 resblks - XFS_IALLOC_SPACE_RES(mp));
1100 if (error) {
1101 ASSERT(error != -ENOSPC);
1102 goto out_trans_cancel;
1103 }
1104 xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1105 xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
1106
1107 if (is_dir) {
1108 error = xfs_dir_init(tp, ip, dp);
1109 if (error)
1110 goto out_trans_cancel;
1111
1112 xfs_bumplink(tp, dp);
1113 }
1114
1115 /*
1116 * Create ip with a reference from dp, and add '.' and '..' references
1117 * if it's a directory.
1118 */
1119 xfs_dir_update_hook(dp, ip, 1, name);
1120
1121 /*
1122 * If this is a synchronous mount, make sure that the
1123 * create transaction goes to disk before returning to
1124 * the user.
1125 */
1126 if (xfs_has_wsync(mp) || xfs_has_dirsync(mp))
1127 xfs_trans_set_sync(tp);
1128
1129 /*
1130 * Attach the dquot(s) to the inodes and modify them incore.
1131 * These ids of the inode couldn't have changed since the new
1132 * inode has been locked ever since it was created.
1133 */
1134 xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp, pdqp);
1135
1136 error = xfs_trans_commit(tp);
1137 if (error)
1138 goto out_release_inode;
1139
1140 xfs_qm_dqrele(udqp);
1141 xfs_qm_dqrele(gdqp);
1142 xfs_qm_dqrele(pdqp);
1143
1144 *ipp = ip;
1145 return 0;
1146
1147 out_trans_cancel:
1148 xfs_trans_cancel(tp);
1149 out_release_inode:
1150 /*
1151 * Wait until after the current transaction is aborted to finish the
1152 * setup of the inode and release the inode. This prevents recursive
1153 * transactions and deadlocks from xfs_inactive.
1154 */
1155 if (ip) {
1156 xfs_finish_inode_setup(ip);
1157 xfs_irele(ip);
1158 }
1159 out_release_dquots:
1160 xfs_qm_dqrele(udqp);
1161 xfs_qm_dqrele(gdqp);
1162 xfs_qm_dqrele(pdqp);
1163
1164 if (unlock_dp_on_error)
1165 xfs_iunlock(dp, XFS_ILOCK_EXCL);
1166 return error;
1167}
1168
1169int
1170xfs_create_tmpfile(
1171 struct mnt_idmap *idmap,
1172 struct xfs_inode *dp,
1173 umode_t mode,
1174 struct xfs_inode **ipp)
1175{
1176 struct xfs_mount *mp = dp->i_mount;
1177 struct xfs_inode *ip = NULL;
1178 struct xfs_trans *tp = NULL;
1179 int error;
1180 prid_t prid;
1181 struct xfs_dquot *udqp = NULL;
1182 struct xfs_dquot *gdqp = NULL;
1183 struct xfs_dquot *pdqp = NULL;
1184 struct xfs_trans_res *tres;
1185 uint resblks;
1186 xfs_ino_t ino;
1187
1188 if (xfs_is_shutdown(mp))
1189 return -EIO;
1190
1191 prid = xfs_get_initial_prid(dp);
1192
1193 /*
1194 * Make sure that we have allocated dquot(s) on disk.
1195 */
1196 error = xfs_qm_vop_dqalloc(dp, mapped_fsuid(idmap, &init_user_ns),
1197 mapped_fsgid(idmap, &init_user_ns), prid,
1198 XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
1199 &udqp, &gdqp, &pdqp);
1200 if (error)
1201 return error;
1202
1203 resblks = XFS_IALLOC_SPACE_RES(mp);
1204 tres = &M_RES(mp)->tr_create_tmpfile;
1205
1206 error = xfs_trans_alloc_icreate(mp, tres, udqp, gdqp, pdqp, resblks,
1207 &tp);
1208 if (error)
1209 goto out_release_dquots;
1210
1211 error = xfs_dialloc(&tp, dp->i_ino, mode, &ino);
1212 if (!error)
1213 error = xfs_init_new_inode(idmap, tp, dp, ino, mode,
1214 0, 0, prid, false, &ip);
1215 if (error)
1216 goto out_trans_cancel;
1217
1218 if (xfs_has_wsync(mp))
1219 xfs_trans_set_sync(tp);
1220
1221 /*
1222 * Attach the dquot(s) to the inodes and modify them incore.
1223 * These ids of the inode couldn't have changed since the new
1224 * inode has been locked ever since it was created.
1225 */
1226 xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp, pdqp);
1227
1228 error = xfs_iunlink(tp, ip);
1229 if (error)
1230 goto out_trans_cancel;
1231
1232 error = xfs_trans_commit(tp);
1233 if (error)
1234 goto out_release_inode;
1235
1236 xfs_qm_dqrele(udqp);
1237 xfs_qm_dqrele(gdqp);
1238 xfs_qm_dqrele(pdqp);
1239
1240 *ipp = ip;
1241 return 0;
1242
1243 out_trans_cancel:
1244 xfs_trans_cancel(tp);
1245 out_release_inode:
1246 /*
1247 * Wait until after the current transaction is aborted to finish the
1248 * setup of the inode and release the inode. This prevents recursive
1249 * transactions and deadlocks from xfs_inactive.
1250 */
1251 if (ip) {
1252 xfs_finish_inode_setup(ip);
1253 xfs_irele(ip);
1254 }
1255 out_release_dquots:
1256 xfs_qm_dqrele(udqp);
1257 xfs_qm_dqrele(gdqp);
1258 xfs_qm_dqrele(pdqp);
1259
1260 return error;
1261}
1262
1263int
1264xfs_link(
1265 xfs_inode_t *tdp,
1266 xfs_inode_t *sip,
1267 struct xfs_name *target_name)
1268{
1269 xfs_mount_t *mp = tdp->i_mount;
1270 xfs_trans_t *tp;
1271 int error, nospace_error = 0;
1272 int resblks;
1273
1274 trace_xfs_link(tdp, target_name);
1275
1276 ASSERT(!S_ISDIR(VFS_I(sip)->i_mode));
1277
1278 if (xfs_is_shutdown(mp))
1279 return -EIO;
1280 if (xfs_ifork_zapped(tdp, XFS_DATA_FORK))
1281 return -EIO;
1282
1283 error = xfs_qm_dqattach(sip);
1284 if (error)
1285 goto std_return;
1286
1287 error = xfs_qm_dqattach(tdp);
1288 if (error)
1289 goto std_return;
1290
1291 resblks = XFS_LINK_SPACE_RES(mp, target_name->len);
1292 error = xfs_trans_alloc_dir(tdp, &M_RES(mp)->tr_link, sip, &resblks,
1293 &tp, &nospace_error);
1294 if (error)
1295 goto std_return;
1296
1297 /*
1298 * If we are using project inheritance, we only allow hard link
1299 * creation in our tree when the project IDs are the same; else
1300 * the tree quota mechanism could be circumvented.
1301 */
1302 if (unlikely((tdp->i_diflags & XFS_DIFLAG_PROJINHERIT) &&
1303 tdp->i_projid != sip->i_projid)) {
1304 /*
1305 * Project quota setup skips special files which can
1306 * leave inodes in a PROJINHERIT directory without a
1307 * project ID set. We need to allow links to be made
1308 * to these "project-less" inodes because userspace
1309 * expects them to succeed after project ID setup,
1310 * but everything else should be rejected.
1311 */
1312 if (!special_file(VFS_I(sip)->i_mode) ||
1313 sip->i_projid != 0) {
1314 error = -EXDEV;
1315 goto error_return;
1316 }
1317 }
1318
1319 if (!resblks) {
1320 error = xfs_dir_canenter(tp, tdp, target_name);
1321 if (error)
1322 goto error_return;
1323 }
1324
1325 /*
1326 * Handle initial link state of O_TMPFILE inode
1327 */
1328 if (VFS_I(sip)->i_nlink == 0) {
1329 struct xfs_perag *pag;
1330
1331 pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, sip->i_ino));
1332 error = xfs_iunlink_remove(tp, pag, sip);
1333 xfs_perag_put(pag);
1334 if (error)
1335 goto error_return;
1336 }
1337
1338 error = xfs_dir_createname(tp, tdp, target_name, sip->i_ino,
1339 resblks);
1340 if (error)
1341 goto error_return;
1342 xfs_trans_ichgtime(tp, tdp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1343 xfs_trans_log_inode(tp, tdp, XFS_ILOG_CORE);
1344
1345 xfs_bumplink(tp, sip);
1346 xfs_dir_update_hook(tdp, sip, 1, target_name);
1347
1348 /*
1349 * If this is a synchronous mount, make sure that the
1350 * link transaction goes to disk before returning to
1351 * the user.
1352 */
1353 if (xfs_has_wsync(mp) || xfs_has_dirsync(mp))
1354 xfs_trans_set_sync(tp);
1355
1356 return xfs_trans_commit(tp);
1357
1358 error_return:
1359 xfs_trans_cancel(tp);
1360 std_return:
1361 if (error == -ENOSPC && nospace_error)
1362 error = nospace_error;
1363 return error;
1364}
1365
1366/* Clear the reflink flag and the cowblocks tag if possible. */
1367static void
1368xfs_itruncate_clear_reflink_flags(
1369 struct xfs_inode *ip)
1370{
1371 struct xfs_ifork *dfork;
1372 struct xfs_ifork *cfork;
1373
1374 if (!xfs_is_reflink_inode(ip))
1375 return;
1376 dfork = xfs_ifork_ptr(ip, XFS_DATA_FORK);
1377 cfork = xfs_ifork_ptr(ip, XFS_COW_FORK);
1378 if (dfork->if_bytes == 0 && cfork->if_bytes == 0)
1379 ip->i_diflags2 &= ~XFS_DIFLAG2_REFLINK;
1380 if (cfork->if_bytes == 0)
1381 xfs_inode_clear_cowblocks_tag(ip);
1382}
1383
1384/*
1385 * Free up the underlying blocks past new_size. The new size must be smaller
1386 * than the current size. This routine can be used both for the attribute and
1387 * data fork, and does not modify the inode size, which is left to the caller.
1388 *
1389 * The transaction passed to this routine must have made a permanent log
1390 * reservation of at least XFS_ITRUNCATE_LOG_RES. This routine may commit the
1391 * given transaction and start new ones, so make sure everything involved in
1392 * the transaction is tidy before calling here. Some transaction will be
1393 * returned to the caller to be committed. The incoming transaction must
1394 * already include the inode, and both inode locks must be held exclusively.
1395 * The inode must also be "held" within the transaction. On return the inode
1396 * will be "held" within the returned transaction. This routine does NOT
1397 * require any disk space to be reserved for it within the transaction.
1398 *
1399 * If we get an error, we must return with the inode locked and linked into the
1400 * current transaction. This keeps things simple for the higher level code,
1401 * because it always knows that the inode is locked and held in the transaction
1402 * that returns to it whether errors occur or not. We don't mark the inode
1403 * dirty on error so that transactions can be easily aborted if possible.
1404 */
1405int
1406xfs_itruncate_extents_flags(
1407 struct xfs_trans **tpp,
1408 struct xfs_inode *ip,
1409 int whichfork,
1410 xfs_fsize_t new_size,
1411 int flags)
1412{
1413 struct xfs_mount *mp = ip->i_mount;
1414 struct xfs_trans *tp = *tpp;
1415 xfs_fileoff_t first_unmap_block;
1416 int error = 0;
1417
1418 xfs_assert_ilocked(ip, XFS_ILOCK_EXCL);
1419 if (atomic_read(&VFS_I(ip)->i_count))
1420 xfs_assert_ilocked(ip, XFS_IOLOCK_EXCL);
1421 ASSERT(new_size <= XFS_ISIZE(ip));
1422 ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
1423 ASSERT(ip->i_itemp != NULL);
1424 ASSERT(ip->i_itemp->ili_lock_flags == 0);
1425 ASSERT(!XFS_NOT_DQATTACHED(mp, ip));
1426
1427 trace_xfs_itruncate_extents_start(ip, new_size);
1428
1429 flags |= xfs_bmapi_aflag(whichfork);
1430
1431 /*
1432 * Since it is possible for space to become allocated beyond
1433 * the end of the file (in a crash where the space is allocated
1434 * but the inode size is not yet updated), simply remove any
1435 * blocks which show up between the new EOF and the maximum
1436 * possible file size.
1437 *
1438 * We have to free all the blocks to the bmbt maximum offset, even if
1439 * the page cache can't scale that far.
1440 */
1441 first_unmap_block = XFS_B_TO_FSB(mp, (xfs_ufsize_t)new_size);
1442 if (!xfs_verify_fileoff(mp, first_unmap_block)) {
1443 WARN_ON_ONCE(first_unmap_block > XFS_MAX_FILEOFF);
1444 return 0;
1445 }
1446
1447 error = xfs_bunmapi_range(&tp, ip, flags, first_unmap_block,
1448 XFS_MAX_FILEOFF);
1449 if (error)
1450 goto out;
1451
1452 if (whichfork == XFS_DATA_FORK) {
1453 /* Remove all pending CoW reservations. */
1454 error = xfs_reflink_cancel_cow_blocks(ip, &tp,
1455 first_unmap_block, XFS_MAX_FILEOFF, true);
1456 if (error)
1457 goto out;
1458
1459 xfs_itruncate_clear_reflink_flags(ip);
1460 }
1461
1462 /*
1463 * Always re-log the inode so that our permanent transaction can keep
1464 * on rolling it forward in the log.
1465 */
1466 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1467
1468 trace_xfs_itruncate_extents_end(ip, new_size);
1469
1470out:
1471 *tpp = tp;
1472 return error;
1473}
1474
1475int
1476xfs_release(
1477 xfs_inode_t *ip)
1478{
1479 xfs_mount_t *mp = ip->i_mount;
1480 int error = 0;
1481
1482 if (!S_ISREG(VFS_I(ip)->i_mode) || (VFS_I(ip)->i_mode == 0))
1483 return 0;
1484
1485 /* If this is a read-only mount, don't do this (would generate I/O) */
1486 if (xfs_is_readonly(mp))
1487 return 0;
1488
1489 if (!xfs_is_shutdown(mp)) {
1490 int truncated;
1491
1492 /*
1493 * If we previously truncated this file and removed old data
1494 * in the process, we want to initiate "early" writeout on
1495 * the last close. This is an attempt to combat the notorious
1496 * NULL files problem which is particularly noticeable from a
1497 * truncate down, buffered (re-)write (delalloc), followed by
1498 * a crash. What we are effectively doing here is
1499 * significantly reducing the time window where we'd otherwise
1500 * be exposed to that problem.
1501 */
1502 truncated = xfs_iflags_test_and_clear(ip, XFS_ITRUNCATED);
1503 if (truncated) {
1504 xfs_iflags_clear(ip, XFS_IDIRTY_RELEASE);
1505 if (ip->i_delayed_blks > 0) {
1506 error = filemap_flush(VFS_I(ip)->i_mapping);
1507 if (error)
1508 return error;
1509 }
1510 }
1511 }
1512
1513 if (VFS_I(ip)->i_nlink == 0)
1514 return 0;
1515
1516 /*
1517 * If we can't get the iolock just skip truncating the blocks past EOF
1518 * because we could deadlock with the mmap_lock otherwise. We'll get
1519 * another chance to drop them once the last reference to the inode is
1520 * dropped, so we'll never leak blocks permanently.
1521 */
1522 if (!xfs_ilock_nowait(ip, XFS_IOLOCK_EXCL))
1523 return 0;
1524
1525 if (xfs_can_free_eofblocks(ip, false)) {
1526 /*
1527 * Check if the inode is being opened, written and closed
1528 * frequently and we have delayed allocation blocks outstanding
1529 * (e.g. streaming writes from the NFS server), truncating the
1530 * blocks past EOF will cause fragmentation to occur.
1531 *
1532 * In this case don't do the truncation, but we have to be
1533 * careful how we detect this case. Blocks beyond EOF show up as
1534 * i_delayed_blks even when the inode is clean, so we need to
1535 * truncate them away first before checking for a dirty release.
1536 * Hence on the first dirty close we will still remove the
1537 * speculative allocation, but after that we will leave it in
1538 * place.
1539 */
1540 if (xfs_iflags_test(ip, XFS_IDIRTY_RELEASE))
1541 goto out_unlock;
1542
1543 error = xfs_free_eofblocks(ip);
1544 if (error)
1545 goto out_unlock;
1546
1547 /* delalloc blocks after truncation means it really is dirty */
1548 if (ip->i_delayed_blks)
1549 xfs_iflags_set(ip, XFS_IDIRTY_RELEASE);
1550 }
1551
1552out_unlock:
1553 xfs_iunlock(ip, XFS_IOLOCK_EXCL);
1554 return error;
1555}
1556
1557/*
1558 * xfs_inactive_truncate
1559 *
1560 * Called to perform a truncate when an inode becomes unlinked.
1561 */
1562STATIC int
1563xfs_inactive_truncate(
1564 struct xfs_inode *ip)
1565{
1566 struct xfs_mount *mp = ip->i_mount;
1567 struct xfs_trans *tp;
1568 int error;
1569
1570 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, 0, 0, 0, &tp);
1571 if (error) {
1572 ASSERT(xfs_is_shutdown(mp));
1573 return error;
1574 }
1575 xfs_ilock(ip, XFS_ILOCK_EXCL);
1576 xfs_trans_ijoin(tp, ip, 0);
1577
1578 /*
1579 * Log the inode size first to prevent stale data exposure in the event
1580 * of a system crash before the truncate completes. See the related
1581 * comment in xfs_vn_setattr_size() for details.
1582 */
1583 ip->i_disk_size = 0;
1584 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1585
1586 error = xfs_itruncate_extents(&tp, ip, XFS_DATA_FORK, 0);
1587 if (error)
1588 goto error_trans_cancel;
1589
1590 ASSERT(ip->i_df.if_nextents == 0);
1591
1592 error = xfs_trans_commit(tp);
1593 if (error)
1594 goto error_unlock;
1595
1596 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1597 return 0;
1598
1599error_trans_cancel:
1600 xfs_trans_cancel(tp);
1601error_unlock:
1602 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1603 return error;
1604}
1605
1606/*
1607 * xfs_inactive_ifree()
1608 *
1609 * Perform the inode free when an inode is unlinked.
1610 */
1611STATIC int
1612xfs_inactive_ifree(
1613 struct xfs_inode *ip)
1614{
1615 struct xfs_mount *mp = ip->i_mount;
1616 struct xfs_trans *tp;
1617 int error;
1618
1619 /*
1620 * We try to use a per-AG reservation for any block needed by the finobt
1621 * tree, but as the finobt feature predates the per-AG reservation
1622 * support a degraded file system might not have enough space for the
1623 * reservation at mount time. In that case try to dip into the reserved
1624 * pool and pray.
1625 *
1626 * Send a warning if the reservation does happen to fail, as the inode
1627 * now remains allocated and sits on the unlinked list until the fs is
1628 * repaired.
1629 */
1630 if (unlikely(mp->m_finobt_nores)) {
1631 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ifree,
1632 XFS_IFREE_SPACE_RES(mp), 0, XFS_TRANS_RESERVE,
1633 &tp);
1634 } else {
1635 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ifree, 0, 0, 0, &tp);
1636 }
1637 if (error) {
1638 if (error == -ENOSPC) {
1639 xfs_warn_ratelimited(mp,
1640 "Failed to remove inode(s) from unlinked list. "
1641 "Please free space, unmount and run xfs_repair.");
1642 } else {
1643 ASSERT(xfs_is_shutdown(mp));
1644 }
1645 return error;
1646 }
1647
1648 /*
1649 * We do not hold the inode locked across the entire rolling transaction
1650 * here. We only need to hold it for the first transaction that
1651 * xfs_ifree() builds, which may mark the inode XFS_ISTALE if the
1652 * underlying cluster buffer is freed. Relogging an XFS_ISTALE inode
1653 * here breaks the relationship between cluster buffer invalidation and
1654 * stale inode invalidation on cluster buffer item journal commit
1655 * completion, and can result in leaving dirty stale inodes hanging
1656 * around in memory.
1657 *
1658 * We have no need for serialising this inode operation against other
1659 * operations - we freed the inode and hence reallocation is required
1660 * and that will serialise on reallocating the space the deferops need
1661 * to free. Hence we can unlock the inode on the first commit of
1662 * the transaction rather than roll it right through the deferops. This
1663 * avoids relogging the XFS_ISTALE inode.
1664 *
1665 * We check that xfs_ifree() hasn't grown an internal transaction roll
1666 * by asserting that the inode is still locked when it returns.
1667 */
1668 xfs_ilock(ip, XFS_ILOCK_EXCL);
1669 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
1670
1671 error = xfs_ifree(tp, ip);
1672 xfs_assert_ilocked(ip, XFS_ILOCK_EXCL);
1673 if (error) {
1674 /*
1675 * If we fail to free the inode, shut down. The cancel
1676 * might do that, we need to make sure. Otherwise the
1677 * inode might be lost for a long time or forever.
1678 */
1679 if (!xfs_is_shutdown(mp)) {
1680 xfs_notice(mp, "%s: xfs_ifree returned error %d",
1681 __func__, error);
1682 xfs_force_shutdown(mp, SHUTDOWN_META_IO_ERROR);
1683 }
1684 xfs_trans_cancel(tp);
1685 return error;
1686 }
1687
1688 /*
1689 * Credit the quota account(s). The inode is gone.
1690 */
1691 xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_ICOUNT, -1);
1692
1693 return xfs_trans_commit(tp);
1694}
1695
1696/*
1697 * Returns true if we need to update the on-disk metadata before we can free
1698 * the memory used by this inode. Updates include freeing post-eof
1699 * preallocations; freeing COW staging extents; and marking the inode free in
1700 * the inobt if it is on the unlinked list.
1701 */
1702bool
1703xfs_inode_needs_inactive(
1704 struct xfs_inode *ip)
1705{
1706 struct xfs_mount *mp = ip->i_mount;
1707 struct xfs_ifork *cow_ifp = xfs_ifork_ptr(ip, XFS_COW_FORK);
1708
1709 /*
1710 * If the inode is already free, then there can be nothing
1711 * to clean up here.
1712 */
1713 if (VFS_I(ip)->i_mode == 0)
1714 return false;
1715
1716 /*
1717 * If this is a read-only mount, don't do this (would generate I/O)
1718 * unless we're in log recovery and cleaning the iunlinked list.
1719 */
1720 if (xfs_is_readonly(mp) && !xlog_recovery_needed(mp->m_log))
1721 return false;
1722
1723 /* If the log isn't running, push inodes straight to reclaim. */
1724 if (xfs_is_shutdown(mp) || xfs_has_norecovery(mp))
1725 return false;
1726
1727 /* Metadata inodes require explicit resource cleanup. */
1728 if (xfs_is_metadata_inode(ip))
1729 return false;
1730
1731 /* Want to clean out the cow blocks if there are any. */
1732 if (cow_ifp && cow_ifp->if_bytes > 0)
1733 return true;
1734
1735 /* Unlinked files must be freed. */
1736 if (VFS_I(ip)->i_nlink == 0)
1737 return true;
1738
1739 /*
1740 * This file isn't being freed, so check if there are post-eof blocks
1741 * to free. @force is true because we are evicting an inode from the
1742 * cache. Post-eof blocks must be freed, lest we end up with broken
1743 * free space accounting.
1744 *
1745 * Note: don't bother with iolock here since lockdep complains about
1746 * acquiring it in reclaim context. We have the only reference to the
1747 * inode at this point anyways.
1748 */
1749 return xfs_can_free_eofblocks(ip, true);
1750}
1751
1752/*
1753 * Save health status somewhere, if we're dumping an inode with uncorrected
1754 * errors and online repair isn't running.
1755 */
1756static inline void
1757xfs_inactive_health(
1758 struct xfs_inode *ip)
1759{
1760 struct xfs_mount *mp = ip->i_mount;
1761 struct xfs_perag *pag;
1762 unsigned int sick;
1763 unsigned int checked;
1764
1765 xfs_inode_measure_sickness(ip, &sick, &checked);
1766 if (!sick)
1767 return;
1768
1769 trace_xfs_inode_unfixed_corruption(ip, sick);
1770
1771 if (sick & XFS_SICK_INO_FORGET)
1772 return;
1773
1774 pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));
1775 if (!pag) {
1776 /* There had better still be a perag structure! */
1777 ASSERT(0);
1778 return;
1779 }
1780
1781 xfs_ag_mark_sick(pag, XFS_SICK_AG_INODES);
1782 xfs_perag_put(pag);
1783}
1784
1785/*
1786 * xfs_inactive
1787 *
1788 * This is called when the vnode reference count for the vnode
1789 * goes to zero. If the file has been unlinked, then it must
1790 * now be truncated. Also, we clear all of the read-ahead state
1791 * kept for the inode here since the file is now closed.
1792 */
1793int
1794xfs_inactive(
1795 xfs_inode_t *ip)
1796{
1797 struct xfs_mount *mp;
1798 int error = 0;
1799 int truncate = 0;
1800
1801 /*
1802 * If the inode is already free, then there can be nothing
1803 * to clean up here.
1804 */
1805 if (VFS_I(ip)->i_mode == 0) {
1806 ASSERT(ip->i_df.if_broot_bytes == 0);
1807 goto out;
1808 }
1809
1810 mp = ip->i_mount;
1811 ASSERT(!xfs_iflags_test(ip, XFS_IRECOVERY));
1812
1813 xfs_inactive_health(ip);
1814
1815 /*
1816 * If this is a read-only mount, don't do this (would generate I/O)
1817 * unless we're in log recovery and cleaning the iunlinked list.
1818 */
1819 if (xfs_is_readonly(mp) && !xlog_recovery_needed(mp->m_log))
1820 goto out;
1821
1822 /* Metadata inodes require explicit resource cleanup. */
1823 if (xfs_is_metadata_inode(ip))
1824 goto out;
1825
1826 /* Try to clean out the cow blocks if there are any. */
1827 if (xfs_inode_has_cow_data(ip))
1828 xfs_reflink_cancel_cow_range(ip, 0, NULLFILEOFF, true);
1829
1830 if (VFS_I(ip)->i_nlink != 0) {
1831 /*
1832 * force is true because we are evicting an inode from the
1833 * cache. Post-eof blocks must be freed, lest we end up with
1834 * broken free space accounting.
1835 *
1836 * Note: don't bother with iolock here since lockdep complains
1837 * about acquiring it in reclaim context. We have the only
1838 * reference to the inode at this point anyways.
1839 */
1840 if (xfs_can_free_eofblocks(ip, true))
1841 error = xfs_free_eofblocks(ip);
1842
1843 goto out;
1844 }
1845
1846 if (S_ISREG(VFS_I(ip)->i_mode) &&
1847 (ip->i_disk_size != 0 || XFS_ISIZE(ip) != 0 ||
1848 ip->i_df.if_nextents > 0 || ip->i_delayed_blks > 0))
1849 truncate = 1;
1850
1851 if (xfs_iflags_test(ip, XFS_IQUOTAUNCHECKED)) {
1852 /*
1853 * If this inode is being inactivated during a quotacheck and
1854 * has not yet been scanned by quotacheck, we /must/ remove
1855 * the dquots from the inode before inactivation changes the
1856 * block and inode counts. Most probably this is a result of
1857 * reloading the incore iunlinked list to purge unrecovered
1858 * unlinked inodes.
1859 */
1860 xfs_qm_dqdetach(ip);
1861 } else {
1862 error = xfs_qm_dqattach(ip);
1863 if (error)
1864 goto out;
1865 }
1866
1867 if (S_ISLNK(VFS_I(ip)->i_mode))
1868 error = xfs_inactive_symlink(ip);
1869 else if (truncate)
1870 error = xfs_inactive_truncate(ip);
1871 if (error)
1872 goto out;
1873
1874 /*
1875 * If there are attributes associated with the file then blow them away
1876 * now. The code calls a routine that recursively deconstructs the
1877 * attribute fork. If also blows away the in-core attribute fork.
1878 */
1879 if (xfs_inode_has_attr_fork(ip)) {
1880 error = xfs_attr_inactive(ip);
1881 if (error)
1882 goto out;
1883 }
1884
1885 ASSERT(ip->i_forkoff == 0);
1886
1887 /*
1888 * Free the inode.
1889 */
1890 error = xfs_inactive_ifree(ip);
1891
1892out:
1893 /*
1894 * We're done making metadata updates for this inode, so we can release
1895 * the attached dquots.
1896 */
1897 xfs_qm_dqdetach(ip);
1898 return error;
1899}
1900
1901/*
1902 * In-Core Unlinked List Lookups
1903 * =============================
1904 *
1905 * Every inode is supposed to be reachable from some other piece of metadata
1906 * with the exception of the root directory. Inodes with a connection to a
1907 * file descriptor but not linked from anywhere in the on-disk directory tree
1908 * are collectively known as unlinked inodes, though the filesystem itself
1909 * maintains links to these inodes so that on-disk metadata are consistent.
1910 *
1911 * XFS implements a per-AG on-disk hash table of unlinked inodes. The AGI
1912 * header contains a number of buckets that point to an inode, and each inode
1913 * record has a pointer to the next inode in the hash chain. This
1914 * singly-linked list causes scaling problems in the iunlink remove function
1915 * because we must walk that list to find the inode that points to the inode
1916 * being removed from the unlinked hash bucket list.
1917 *
1918 * Hence we keep an in-memory double linked list to link each inode on an
1919 * unlinked list. Because there are 64 unlinked lists per AGI, keeping pointer
1920 * based lists would require having 64 list heads in the perag, one for each
1921 * list. This is expensive in terms of memory (think millions of AGs) and cache
1922 * misses on lookups. Instead, use the fact that inodes on the unlinked list
1923 * must be referenced at the VFS level to keep them on the list and hence we
1924 * have an existence guarantee for inodes on the unlinked list.
1925 *
1926 * Given we have an existence guarantee, we can use lockless inode cache lookups
1927 * to resolve aginos to xfs inodes. This means we only need 8 bytes per inode
1928 * for the double linked unlinked list, and we don't need any extra locking to
1929 * keep the list safe as all manipulations are done under the AGI buffer lock.
1930 * Keeping the list up to date does not require memory allocation, just finding
1931 * the XFS inode and updating the next/prev unlinked list aginos.
1932 */
1933
1934/*
1935 * Find an inode on the unlinked list. This does not take references to the
1936 * inode as we have existence guarantees by holding the AGI buffer lock and that
1937 * only unlinked, referenced inodes can be on the unlinked inode list. If we
1938 * don't find the inode in cache, then let the caller handle the situation.
1939 */
1940static struct xfs_inode *
1941xfs_iunlink_lookup(
1942 struct xfs_perag *pag,
1943 xfs_agino_t agino)
1944{
1945 struct xfs_inode *ip;
1946
1947 rcu_read_lock();
1948 ip = radix_tree_lookup(&pag->pag_ici_root, agino);
1949 if (!ip) {
1950 /* Caller can handle inode not being in memory. */
1951 rcu_read_unlock();
1952 return NULL;
1953 }
1954
1955 /*
1956 * Inode in RCU freeing limbo should not happen. Warn about this and
1957 * let the caller handle the failure.
1958 */
1959 if (WARN_ON_ONCE(!ip->i_ino)) {
1960 rcu_read_unlock();
1961 return NULL;
1962 }
1963 ASSERT(!xfs_iflags_test(ip, XFS_IRECLAIMABLE | XFS_IRECLAIM));
1964 rcu_read_unlock();
1965 return ip;
1966}
1967
1968/*
1969 * Update the prev pointer of the next agino. Returns -ENOLINK if the inode
1970 * is not in cache.
1971 */
1972static int
1973xfs_iunlink_update_backref(
1974 struct xfs_perag *pag,
1975 xfs_agino_t prev_agino,
1976 xfs_agino_t next_agino)
1977{
1978 struct xfs_inode *ip;
1979
1980 /* No update necessary if we are at the end of the list. */
1981 if (next_agino == NULLAGINO)
1982 return 0;
1983
1984 ip = xfs_iunlink_lookup(pag, next_agino);
1985 if (!ip)
1986 return -ENOLINK;
1987
1988 ip->i_prev_unlinked = prev_agino;
1989 return 0;
1990}
1991
1992/*
1993 * Point the AGI unlinked bucket at an inode and log the results. The caller
1994 * is responsible for validating the old value.
1995 */
1996STATIC int
1997xfs_iunlink_update_bucket(
1998 struct xfs_trans *tp,
1999 struct xfs_perag *pag,
2000 struct xfs_buf *agibp,
2001 unsigned int bucket_index,
2002 xfs_agino_t new_agino)
2003{
2004 struct xfs_agi *agi = agibp->b_addr;
2005 xfs_agino_t old_value;
2006 int offset;
2007
2008 ASSERT(xfs_verify_agino_or_null(pag, new_agino));
2009
2010 old_value = be32_to_cpu(agi->agi_unlinked[bucket_index]);
2011 trace_xfs_iunlink_update_bucket(tp->t_mountp, pag->pag_agno, bucket_index,
2012 old_value, new_agino);
2013
2014 /*
2015 * We should never find the head of the list already set to the value
2016 * passed in because either we're adding or removing ourselves from the
2017 * head of the list.
2018 */
2019 if (old_value == new_agino) {
2020 xfs_buf_mark_corrupt(agibp);
2021 xfs_ag_mark_sick(pag, XFS_SICK_AG_AGI);
2022 return -EFSCORRUPTED;
2023 }
2024
2025 agi->agi_unlinked[bucket_index] = cpu_to_be32(new_agino);
2026 offset = offsetof(struct xfs_agi, agi_unlinked) +
2027 (sizeof(xfs_agino_t) * bucket_index);
2028 xfs_trans_log_buf(tp, agibp, offset, offset + sizeof(xfs_agino_t) - 1);
2029 return 0;
2030}
2031
2032/*
2033 * Load the inode @next_agino into the cache and set its prev_unlinked pointer
2034 * to @prev_agino. Caller must hold the AGI to synchronize with other changes
2035 * to the unlinked list.
2036 */
2037STATIC int
2038xfs_iunlink_reload_next(
2039 struct xfs_trans *tp,
2040 struct xfs_buf *agibp,
2041 xfs_agino_t prev_agino,
2042 xfs_agino_t next_agino)
2043{
2044 struct xfs_perag *pag = agibp->b_pag;
2045 struct xfs_mount *mp = pag->pag_mount;
2046 struct xfs_inode *next_ip = NULL;
2047 xfs_ino_t ino;
2048 int error;
2049
2050 ASSERT(next_agino != NULLAGINO);
2051
2052#ifdef DEBUG
2053 rcu_read_lock();
2054 next_ip = radix_tree_lookup(&pag->pag_ici_root, next_agino);
2055 ASSERT(next_ip == NULL);
2056 rcu_read_unlock();
2057#endif
2058
2059 xfs_info_ratelimited(mp,
2060 "Found unrecovered unlinked inode 0x%x in AG 0x%x. Initiating recovery.",
2061 next_agino, pag->pag_agno);
2062
2063 /*
2064 * Use an untrusted lookup just to be cautious in case the AGI has been
2065 * corrupted and now points at a free inode. That shouldn't happen,
2066 * but we'd rather shut down now since we're already running in a weird
2067 * situation.
2068 */
2069 ino = XFS_AGINO_TO_INO(mp, pag->pag_agno, next_agino);
2070 error = xfs_iget(mp, tp, ino, XFS_IGET_UNTRUSTED, 0, &next_ip);
2071 if (error) {
2072 xfs_ag_mark_sick(pag, XFS_SICK_AG_AGI);
2073 return error;
2074 }
2075
2076 /* If this is not an unlinked inode, something is very wrong. */
2077 if (VFS_I(next_ip)->i_nlink != 0) {
2078 xfs_ag_mark_sick(pag, XFS_SICK_AG_AGI);
2079 error = -EFSCORRUPTED;
2080 goto rele;
2081 }
2082
2083 next_ip->i_prev_unlinked = prev_agino;
2084 trace_xfs_iunlink_reload_next(next_ip);
2085rele:
2086 ASSERT(!(VFS_I(next_ip)->i_state & I_DONTCACHE));
2087 if (xfs_is_quotacheck_running(mp) && next_ip)
2088 xfs_iflags_set(next_ip, XFS_IQUOTAUNCHECKED);
2089 xfs_irele(next_ip);
2090 return error;
2091}
2092
2093static int
2094xfs_iunlink_insert_inode(
2095 struct xfs_trans *tp,
2096 struct xfs_perag *pag,
2097 struct xfs_buf *agibp,
2098 struct xfs_inode *ip)
2099{
2100 struct xfs_mount *mp = tp->t_mountp;
2101 struct xfs_agi *agi = agibp->b_addr;
2102 xfs_agino_t next_agino;
2103 xfs_agino_t agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
2104 short bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
2105 int error;
2106
2107 /*
2108 * Get the index into the agi hash table for the list this inode will
2109 * go on. Make sure the pointer isn't garbage and that this inode
2110 * isn't already on the list.
2111 */
2112 next_agino = be32_to_cpu(agi->agi_unlinked[bucket_index]);
2113 if (next_agino == agino ||
2114 !xfs_verify_agino_or_null(pag, next_agino)) {
2115 xfs_buf_mark_corrupt(agibp);
2116 xfs_ag_mark_sick(pag, XFS_SICK_AG_AGI);
2117 return -EFSCORRUPTED;
2118 }
2119
2120 /*
2121 * Update the prev pointer in the next inode to point back to this
2122 * inode.
2123 */
2124 error = xfs_iunlink_update_backref(pag, agino, next_agino);
2125 if (error == -ENOLINK)
2126 error = xfs_iunlink_reload_next(tp, agibp, agino, next_agino);
2127 if (error)
2128 return error;
2129
2130 if (next_agino != NULLAGINO) {
2131 /*
2132 * There is already another inode in the bucket, so point this
2133 * inode to the current head of the list.
2134 */
2135 error = xfs_iunlink_log_inode(tp, ip, pag, next_agino);
2136 if (error)
2137 return error;
2138 ip->i_next_unlinked = next_agino;
2139 }
2140
2141 /* Point the head of the list to point to this inode. */
2142 ip->i_prev_unlinked = NULLAGINO;
2143 return xfs_iunlink_update_bucket(tp, pag, agibp, bucket_index, agino);
2144}
2145
2146/*
2147 * This is called when the inode's link count has gone to 0 or we are creating
2148 * a tmpfile via O_TMPFILE. The inode @ip must have nlink == 0.
2149 *
2150 * We place the on-disk inode on a list in the AGI. It will be pulled from this
2151 * list when the inode is freed.
2152 */
2153STATIC int
2154xfs_iunlink(
2155 struct xfs_trans *tp,
2156 struct xfs_inode *ip)
2157{
2158 struct xfs_mount *mp = tp->t_mountp;
2159 struct xfs_perag *pag;
2160 struct xfs_buf *agibp;
2161 int error;
2162
2163 ASSERT(VFS_I(ip)->i_nlink == 0);
2164 ASSERT(VFS_I(ip)->i_mode != 0);
2165 trace_xfs_iunlink(ip);
2166
2167 pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));
2168
2169 /* Get the agi buffer first. It ensures lock ordering on the list. */
2170 error = xfs_read_agi(pag, tp, &agibp);
2171 if (error)
2172 goto out;
2173
2174 error = xfs_iunlink_insert_inode(tp, pag, agibp, ip);
2175out:
2176 xfs_perag_put(pag);
2177 return error;
2178}
2179
2180static int
2181xfs_iunlink_remove_inode(
2182 struct xfs_trans *tp,
2183 struct xfs_perag *pag,
2184 struct xfs_buf *agibp,
2185 struct xfs_inode *ip)
2186{
2187 struct xfs_mount *mp = tp->t_mountp;
2188 struct xfs_agi *agi = agibp->b_addr;
2189 xfs_agino_t agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
2190 xfs_agino_t head_agino;
2191 short bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
2192 int error;
2193
2194 trace_xfs_iunlink_remove(ip);
2195
2196 /*
2197 * Get the index into the agi hash table for the list this inode will
2198 * go on. Make sure the head pointer isn't garbage.
2199 */
2200 head_agino = be32_to_cpu(agi->agi_unlinked[bucket_index]);
2201 if (!xfs_verify_agino(pag, head_agino)) {
2202 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
2203 agi, sizeof(*agi));
2204 xfs_ag_mark_sick(pag, XFS_SICK_AG_AGI);
2205 return -EFSCORRUPTED;
2206 }
2207
2208 /*
2209 * Set our inode's next_unlinked pointer to NULL and then return
2210 * the old pointer value so that we can update whatever was previous
2211 * to us in the list to point to whatever was next in the list.
2212 */
2213 error = xfs_iunlink_log_inode(tp, ip, pag, NULLAGINO);
2214 if (error)
2215 return error;
2216
2217 /*
2218 * Update the prev pointer in the next inode to point back to previous
2219 * inode in the chain.
2220 */
2221 error = xfs_iunlink_update_backref(pag, ip->i_prev_unlinked,
2222 ip->i_next_unlinked);
2223 if (error == -ENOLINK)
2224 error = xfs_iunlink_reload_next(tp, agibp, ip->i_prev_unlinked,
2225 ip->i_next_unlinked);
2226 if (error)
2227 return error;
2228
2229 if (head_agino != agino) {
2230 struct xfs_inode *prev_ip;
2231
2232 prev_ip = xfs_iunlink_lookup(pag, ip->i_prev_unlinked);
2233 if (!prev_ip) {
2234 xfs_inode_mark_sick(ip, XFS_SICK_INO_CORE);
2235 return -EFSCORRUPTED;
2236 }
2237
2238 error = xfs_iunlink_log_inode(tp, prev_ip, pag,
2239 ip->i_next_unlinked);
2240 prev_ip->i_next_unlinked = ip->i_next_unlinked;
2241 } else {
2242 /* Point the head of the list to the next unlinked inode. */
2243 error = xfs_iunlink_update_bucket(tp, pag, agibp, bucket_index,
2244 ip->i_next_unlinked);
2245 }
2246
2247 ip->i_next_unlinked = NULLAGINO;
2248 ip->i_prev_unlinked = 0;
2249 return error;
2250}
2251
2252/*
2253 * Pull the on-disk inode from the AGI unlinked list.
2254 */
2255STATIC int
2256xfs_iunlink_remove(
2257 struct xfs_trans *tp,
2258 struct xfs_perag *pag,
2259 struct xfs_inode *ip)
2260{
2261 struct xfs_buf *agibp;
2262 int error;
2263
2264 trace_xfs_iunlink_remove(ip);
2265
2266 /* Get the agi buffer first. It ensures lock ordering on the list. */
2267 error = xfs_read_agi(pag, tp, &agibp);
2268 if (error)
2269 return error;
2270
2271 return xfs_iunlink_remove_inode(tp, pag, agibp, ip);
2272}
2273
2274/*
2275 * Look up the inode number specified and if it is not already marked XFS_ISTALE
2276 * mark it stale. We should only find clean inodes in this lookup that aren't
2277 * already stale.
2278 */
2279static void
2280xfs_ifree_mark_inode_stale(
2281 struct xfs_perag *pag,
2282 struct xfs_inode *free_ip,
2283 xfs_ino_t inum)
2284{
2285 struct xfs_mount *mp = pag->pag_mount;
2286 struct xfs_inode_log_item *iip;
2287 struct xfs_inode *ip;
2288
2289retry:
2290 rcu_read_lock();
2291 ip = radix_tree_lookup(&pag->pag_ici_root, XFS_INO_TO_AGINO(mp, inum));
2292
2293 /* Inode not in memory, nothing to do */
2294 if (!ip) {
2295 rcu_read_unlock();
2296 return;
2297 }
2298
2299 /*
2300 * because this is an RCU protected lookup, we could find a recently
2301 * freed or even reallocated inode during the lookup. We need to check
2302 * under the i_flags_lock for a valid inode here. Skip it if it is not
2303 * valid, the wrong inode or stale.
2304 */
2305 spin_lock(&ip->i_flags_lock);
2306 if (ip->i_ino != inum || __xfs_iflags_test(ip, XFS_ISTALE))
2307 goto out_iflags_unlock;
2308
2309 /*
2310 * Don't try to lock/unlock the current inode, but we _cannot_ skip the
2311 * other inodes that we did not find in the list attached to the buffer
2312 * and are not already marked stale. If we can't lock it, back off and
2313 * retry.
2314 */
2315 if (ip != free_ip) {
2316 if (!xfs_ilock_nowait(ip, XFS_ILOCK_EXCL)) {
2317 spin_unlock(&ip->i_flags_lock);
2318 rcu_read_unlock();
2319 delay(1);
2320 goto retry;
2321 }
2322 }
2323 ip->i_flags |= XFS_ISTALE;
2324
2325 /*
2326 * If the inode is flushing, it is already attached to the buffer. All
2327 * we needed to do here is mark the inode stale so buffer IO completion
2328 * will remove it from the AIL.
2329 */
2330 iip = ip->i_itemp;
2331 if (__xfs_iflags_test(ip, XFS_IFLUSHING)) {
2332 ASSERT(!list_empty(&iip->ili_item.li_bio_list));
2333 ASSERT(iip->ili_last_fields);
2334 goto out_iunlock;
2335 }
2336
2337 /*
2338 * Inodes not attached to the buffer can be released immediately.
2339 * Everything else has to go through xfs_iflush_abort() on journal
2340 * commit as the flock synchronises removal of the inode from the
2341 * cluster buffer against inode reclaim.
2342 */
2343 if (!iip || list_empty(&iip->ili_item.li_bio_list))
2344 goto out_iunlock;
2345
2346 __xfs_iflags_set(ip, XFS_IFLUSHING);
2347 spin_unlock(&ip->i_flags_lock);
2348 rcu_read_unlock();
2349
2350 /* we have a dirty inode in memory that has not yet been flushed. */
2351 spin_lock(&iip->ili_lock);
2352 iip->ili_last_fields = iip->ili_fields;
2353 iip->ili_fields = 0;
2354 iip->ili_fsync_fields = 0;
2355 spin_unlock(&iip->ili_lock);
2356 ASSERT(iip->ili_last_fields);
2357
2358 if (ip != free_ip)
2359 xfs_iunlock(ip, XFS_ILOCK_EXCL);
2360 return;
2361
2362out_iunlock:
2363 if (ip != free_ip)
2364 xfs_iunlock(ip, XFS_ILOCK_EXCL);
2365out_iflags_unlock:
2366 spin_unlock(&ip->i_flags_lock);
2367 rcu_read_unlock();
2368}
2369
2370/*
2371 * A big issue when freeing the inode cluster is that we _cannot_ skip any
2372 * inodes that are in memory - they all must be marked stale and attached to
2373 * the cluster buffer.
2374 */
2375static int
2376xfs_ifree_cluster(
2377 struct xfs_trans *tp,
2378 struct xfs_perag *pag,
2379 struct xfs_inode *free_ip,
2380 struct xfs_icluster *xic)
2381{
2382 struct xfs_mount *mp = free_ip->i_mount;
2383 struct xfs_ino_geometry *igeo = M_IGEO(mp);
2384 struct xfs_buf *bp;
2385 xfs_daddr_t blkno;
2386 xfs_ino_t inum = xic->first_ino;
2387 int nbufs;
2388 int i, j;
2389 int ioffset;
2390 int error;
2391
2392 nbufs = igeo->ialloc_blks / igeo->blocks_per_cluster;
2393
2394 for (j = 0; j < nbufs; j++, inum += igeo->inodes_per_cluster) {
2395 /*
2396 * The allocation bitmap tells us which inodes of the chunk were
2397 * physically allocated. Skip the cluster if an inode falls into
2398 * a sparse region.
2399 */
2400 ioffset = inum - xic->first_ino;
2401 if ((xic->alloc & XFS_INOBT_MASK(ioffset)) == 0) {
2402 ASSERT(ioffset % igeo->inodes_per_cluster == 0);
2403 continue;
2404 }
2405
2406 blkno = XFS_AGB_TO_DADDR(mp, XFS_INO_TO_AGNO(mp, inum),
2407 XFS_INO_TO_AGBNO(mp, inum));
2408
2409 /*
2410 * We obtain and lock the backing buffer first in the process
2411 * here to ensure dirty inodes attached to the buffer remain in
2412 * the flushing state while we mark them stale.
2413 *
2414 * If we scan the in-memory inodes first, then buffer IO can
2415 * complete before we get a lock on it, and hence we may fail
2416 * to mark all the active inodes on the buffer stale.
2417 */
2418 error = xfs_trans_get_buf(tp, mp->m_ddev_targp, blkno,
2419 mp->m_bsize * igeo->blocks_per_cluster,
2420 XBF_UNMAPPED, &bp);
2421 if (error)
2422 return error;
2423
2424 /*
2425 * This buffer may not have been correctly initialised as we
2426 * didn't read it from disk. That's not important because we are
2427 * only using to mark the buffer as stale in the log, and to
2428 * attach stale cached inodes on it. That means it will never be
2429 * dispatched for IO. If it is, we want to know about it, and we
2430 * want it to fail. We can acheive this by adding a write
2431 * verifier to the buffer.
2432 */
2433 bp->b_ops = &xfs_inode_buf_ops;
2434
2435 /*
2436 * Now we need to set all the cached clean inodes as XFS_ISTALE,
2437 * too. This requires lookups, and will skip inodes that we've
2438 * already marked XFS_ISTALE.
2439 */
2440 for (i = 0; i < igeo->inodes_per_cluster; i++)
2441 xfs_ifree_mark_inode_stale(pag, free_ip, inum + i);
2442
2443 xfs_trans_stale_inode_buf(tp, bp);
2444 xfs_trans_binval(tp, bp);
2445 }
2446 return 0;
2447}
2448
2449/*
2450 * This is called to return an inode to the inode free list. The inode should
2451 * already be truncated to 0 length and have no pages associated with it. This
2452 * routine also assumes that the inode is already a part of the transaction.
2453 *
2454 * The on-disk copy of the inode will have been added to the list of unlinked
2455 * inodes in the AGI. We need to remove the inode from that list atomically with
2456 * respect to freeing it here.
2457 */
2458int
2459xfs_ifree(
2460 struct xfs_trans *tp,
2461 struct xfs_inode *ip)
2462{
2463 struct xfs_mount *mp = ip->i_mount;
2464 struct xfs_perag *pag;
2465 struct xfs_icluster xic = { 0 };
2466 struct xfs_inode_log_item *iip = ip->i_itemp;
2467 int error;
2468
2469 xfs_assert_ilocked(ip, XFS_ILOCK_EXCL);
2470 ASSERT(VFS_I(ip)->i_nlink == 0);
2471 ASSERT(ip->i_df.if_nextents == 0);
2472 ASSERT(ip->i_disk_size == 0 || !S_ISREG(VFS_I(ip)->i_mode));
2473 ASSERT(ip->i_nblocks == 0);
2474
2475 pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));
2476
2477 /*
2478 * Free the inode first so that we guarantee that the AGI lock is going
2479 * to be taken before we remove the inode from the unlinked list. This
2480 * makes the AGI lock -> unlinked list modification order the same as
2481 * used in O_TMPFILE creation.
2482 */
2483 error = xfs_difree(tp, pag, ip->i_ino, &xic);
2484 if (error)
2485 goto out;
2486
2487 error = xfs_iunlink_remove(tp, pag, ip);
2488 if (error)
2489 goto out;
2490
2491 /*
2492 * Free any local-format data sitting around before we reset the
2493 * data fork to extents format. Note that the attr fork data has
2494 * already been freed by xfs_attr_inactive.
2495 */
2496 if (ip->i_df.if_format == XFS_DINODE_FMT_LOCAL) {
2497 kfree(ip->i_df.if_data);
2498 ip->i_df.if_data = NULL;
2499 ip->i_df.if_bytes = 0;
2500 }
2501
2502 VFS_I(ip)->i_mode = 0; /* mark incore inode as free */
2503 ip->i_diflags = 0;
2504 ip->i_diflags2 = mp->m_ino_geo.new_diflags2;
2505 ip->i_forkoff = 0; /* mark the attr fork not in use */
2506 ip->i_df.if_format = XFS_DINODE_FMT_EXTENTS;
2507 if (xfs_iflags_test(ip, XFS_IPRESERVE_DM_FIELDS))
2508 xfs_iflags_clear(ip, XFS_IPRESERVE_DM_FIELDS);
2509
2510 /* Don't attempt to replay owner changes for a deleted inode */
2511 spin_lock(&iip->ili_lock);
2512 iip->ili_fields &= ~(XFS_ILOG_AOWNER | XFS_ILOG_DOWNER);
2513 spin_unlock(&iip->ili_lock);
2514
2515 /*
2516 * Bump the generation count so no one will be confused
2517 * by reincarnations of this inode.
2518 */
2519 VFS_I(ip)->i_generation++;
2520 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
2521
2522 if (xic.deleted)
2523 error = xfs_ifree_cluster(tp, pag, ip, &xic);
2524out:
2525 xfs_perag_put(pag);
2526 return error;
2527}
2528
2529/*
2530 * This is called to unpin an inode. The caller must have the inode locked
2531 * in at least shared mode so that the buffer cannot be subsequently pinned
2532 * once someone is waiting for it to be unpinned.
2533 */
2534static void
2535xfs_iunpin(
2536 struct xfs_inode *ip)
2537{
2538 xfs_assert_ilocked(ip, XFS_ILOCK_EXCL | XFS_ILOCK_SHARED);
2539
2540 trace_xfs_inode_unpin_nowait(ip, _RET_IP_);
2541
2542 /* Give the log a push to start the unpinning I/O */
2543 xfs_log_force_seq(ip->i_mount, ip->i_itemp->ili_commit_seq, 0, NULL);
2544
2545}
2546
2547static void
2548__xfs_iunpin_wait(
2549 struct xfs_inode *ip)
2550{
2551 wait_queue_head_t *wq = bit_waitqueue(&ip->i_flags, __XFS_IPINNED_BIT);
2552 DEFINE_WAIT_BIT(wait, &ip->i_flags, __XFS_IPINNED_BIT);
2553
2554 xfs_iunpin(ip);
2555
2556 do {
2557 prepare_to_wait(wq, &wait.wq_entry, TASK_UNINTERRUPTIBLE);
2558 if (xfs_ipincount(ip))
2559 io_schedule();
2560 } while (xfs_ipincount(ip));
2561 finish_wait(wq, &wait.wq_entry);
2562}
2563
2564void
2565xfs_iunpin_wait(
2566 struct xfs_inode *ip)
2567{
2568 if (xfs_ipincount(ip))
2569 __xfs_iunpin_wait(ip);
2570}
2571
2572/*
2573 * Removing an inode from the namespace involves removing the directory entry
2574 * and dropping the link count on the inode. Removing the directory entry can
2575 * result in locking an AGF (directory blocks were freed) and removing a link
2576 * count can result in placing the inode on an unlinked list which results in
2577 * locking an AGI.
2578 *
2579 * The big problem here is that we have an ordering constraint on AGF and AGI
2580 * locking - inode allocation locks the AGI, then can allocate a new extent for
2581 * new inodes, locking the AGF after the AGI. Similarly, freeing the inode
2582 * removes the inode from the unlinked list, requiring that we lock the AGI
2583 * first, and then freeing the inode can result in an inode chunk being freed
2584 * and hence freeing disk space requiring that we lock an AGF.
2585 *
2586 * Hence the ordering that is imposed by other parts of the code is AGI before
2587 * AGF. This means we cannot remove the directory entry before we drop the inode
2588 * reference count and put it on the unlinked list as this results in a lock
2589 * order of AGF then AGI, and this can deadlock against inode allocation and
2590 * freeing. Therefore we must drop the link counts before we remove the
2591 * directory entry.
2592 *
2593 * This is still safe from a transactional point of view - it is not until we
2594 * get to xfs_defer_finish() that we have the possibility of multiple
2595 * transactions in this operation. Hence as long as we remove the directory
2596 * entry and drop the link count in the first transaction of the remove
2597 * operation, there are no transactional constraints on the ordering here.
2598 */
2599int
2600xfs_remove(
2601 xfs_inode_t *dp,
2602 struct xfs_name *name,
2603 xfs_inode_t *ip)
2604{
2605 xfs_mount_t *mp = dp->i_mount;
2606 xfs_trans_t *tp = NULL;
2607 int is_dir = S_ISDIR(VFS_I(ip)->i_mode);
2608 int dontcare;
2609 int error = 0;
2610 uint resblks;
2611
2612 trace_xfs_remove(dp, name);
2613
2614 if (xfs_is_shutdown(mp))
2615 return -EIO;
2616 if (xfs_ifork_zapped(dp, XFS_DATA_FORK))
2617 return -EIO;
2618
2619 error = xfs_qm_dqattach(dp);
2620 if (error)
2621 goto std_return;
2622
2623 error = xfs_qm_dqattach(ip);
2624 if (error)
2625 goto std_return;
2626
2627 /*
2628 * We try to get the real space reservation first, allowing for
2629 * directory btree deletion(s) implying possible bmap insert(s). If we
2630 * can't get the space reservation then we use 0 instead, and avoid the
2631 * bmap btree insert(s) in the directory code by, if the bmap insert
2632 * tries to happen, instead trimming the LAST block from the directory.
2633 *
2634 * Ignore EDQUOT and ENOSPC being returned via nospace_error because
2635 * the directory code can handle a reservationless update and we don't
2636 * want to prevent a user from trying to free space by deleting things.
2637 */
2638 resblks = XFS_REMOVE_SPACE_RES(mp);
2639 error = xfs_trans_alloc_dir(dp, &M_RES(mp)->tr_remove, ip, &resblks,
2640 &tp, &dontcare);
2641 if (error) {
2642 ASSERT(error != -ENOSPC);
2643 goto std_return;
2644 }
2645
2646 /*
2647 * If we're removing a directory perform some additional validation.
2648 */
2649 if (is_dir) {
2650 ASSERT(VFS_I(ip)->i_nlink >= 2);
2651 if (VFS_I(ip)->i_nlink != 2) {
2652 error = -ENOTEMPTY;
2653 goto out_trans_cancel;
2654 }
2655 if (!xfs_dir_isempty(ip)) {
2656 error = -ENOTEMPTY;
2657 goto out_trans_cancel;
2658 }
2659
2660 /* Drop the link from ip's "..". */
2661 error = xfs_droplink(tp, dp);
2662 if (error)
2663 goto out_trans_cancel;
2664
2665 /* Drop the "." link from ip to self. */
2666 error = xfs_droplink(tp, ip);
2667 if (error)
2668 goto out_trans_cancel;
2669
2670 /*
2671 * Point the unlinked child directory's ".." entry to the root
2672 * directory to eliminate back-references to inodes that may
2673 * get freed before the child directory is closed. If the fs
2674 * gets shrunk, this can lead to dirent inode validation errors.
2675 */
2676 if (dp->i_ino != tp->t_mountp->m_sb.sb_rootino) {
2677 error = xfs_dir_replace(tp, ip, &xfs_name_dotdot,
2678 tp->t_mountp->m_sb.sb_rootino, 0);
2679 if (error)
2680 goto out_trans_cancel;
2681 }
2682 } else {
2683 /*
2684 * When removing a non-directory we need to log the parent
2685 * inode here. For a directory this is done implicitly
2686 * by the xfs_droplink call for the ".." entry.
2687 */
2688 xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
2689 }
2690 xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2691
2692 /* Drop the link from dp to ip. */
2693 error = xfs_droplink(tp, ip);
2694 if (error)
2695 goto out_trans_cancel;
2696
2697 error = xfs_dir_removename(tp, dp, name, ip->i_ino, resblks);
2698 if (error) {
2699 ASSERT(error != -ENOENT);
2700 goto out_trans_cancel;
2701 }
2702
2703 /*
2704 * Drop the link from dp to ip, and if ip was a directory, remove the
2705 * '.' and '..' references since we freed the directory.
2706 */
2707 xfs_dir_update_hook(dp, ip, -1, name);
2708
2709 /*
2710 * If this is a synchronous mount, make sure that the
2711 * remove transaction goes to disk before returning to
2712 * the user.
2713 */
2714 if (xfs_has_wsync(mp) || xfs_has_dirsync(mp))
2715 xfs_trans_set_sync(tp);
2716
2717 error = xfs_trans_commit(tp);
2718 if (error)
2719 goto std_return;
2720
2721 if (is_dir && xfs_inode_is_filestream(ip))
2722 xfs_filestream_deassociate(ip);
2723
2724 return 0;
2725
2726 out_trans_cancel:
2727 xfs_trans_cancel(tp);
2728 std_return:
2729 return error;
2730}
2731
2732/*
2733 * Enter all inodes for a rename transaction into a sorted array.
2734 */
2735#define __XFS_SORT_INODES 5
2736STATIC void
2737xfs_sort_for_rename(
2738 struct xfs_inode *dp1, /* in: old (source) directory inode */
2739 struct xfs_inode *dp2, /* in: new (target) directory inode */
2740 struct xfs_inode *ip1, /* in: inode of old entry */
2741 struct xfs_inode *ip2, /* in: inode of new entry */
2742 struct xfs_inode *wip, /* in: whiteout inode */
2743 struct xfs_inode **i_tab,/* out: sorted array of inodes */
2744 int *num_inodes) /* in/out: inodes in array */
2745{
2746 int i, j;
2747
2748 ASSERT(*num_inodes == __XFS_SORT_INODES);
2749 memset(i_tab, 0, *num_inodes * sizeof(struct xfs_inode *));
2750
2751 /*
2752 * i_tab contains a list of pointers to inodes. We initialize
2753 * the table here & we'll sort it. We will then use it to
2754 * order the acquisition of the inode locks.
2755 *
2756 * Note that the table may contain duplicates. e.g., dp1 == dp2.
2757 */
2758 i = 0;
2759 i_tab[i++] = dp1;
2760 i_tab[i++] = dp2;
2761 i_tab[i++] = ip1;
2762 if (ip2)
2763 i_tab[i++] = ip2;
2764 if (wip)
2765 i_tab[i++] = wip;
2766 *num_inodes = i;
2767
2768 /*
2769 * Sort the elements via bubble sort. (Remember, there are at
2770 * most 5 elements to sort, so this is adequate.)
2771 */
2772 for (i = 0; i < *num_inodes; i++) {
2773 for (j = 1; j < *num_inodes; j++) {
2774 if (i_tab[j]->i_ino < i_tab[j-1]->i_ino) {
2775 struct xfs_inode *temp = i_tab[j];
2776 i_tab[j] = i_tab[j-1];
2777 i_tab[j-1] = temp;
2778 }
2779 }
2780 }
2781}
2782
2783static int
2784xfs_finish_rename(
2785 struct xfs_trans *tp)
2786{
2787 /*
2788 * If this is a synchronous mount, make sure that the rename transaction
2789 * goes to disk before returning to the user.
2790 */
2791 if (xfs_has_wsync(tp->t_mountp) || xfs_has_dirsync(tp->t_mountp))
2792 xfs_trans_set_sync(tp);
2793
2794 return xfs_trans_commit(tp);
2795}
2796
2797/*
2798 * xfs_cross_rename()
2799 *
2800 * responsible for handling RENAME_EXCHANGE flag in renameat2() syscall
2801 */
2802STATIC int
2803xfs_cross_rename(
2804 struct xfs_trans *tp,
2805 struct xfs_inode *dp1,
2806 struct xfs_name *name1,
2807 struct xfs_inode *ip1,
2808 struct xfs_inode *dp2,
2809 struct xfs_name *name2,
2810 struct xfs_inode *ip2,
2811 int spaceres)
2812{
2813 int error = 0;
2814 int ip1_flags = 0;
2815 int ip2_flags = 0;
2816 int dp2_flags = 0;
2817
2818 /* Swap inode number for dirent in first parent */
2819 error = xfs_dir_replace(tp, dp1, name1, ip2->i_ino, spaceres);
2820 if (error)
2821 goto out_trans_abort;
2822
2823 /* Swap inode number for dirent in second parent */
2824 error = xfs_dir_replace(tp, dp2, name2, ip1->i_ino, spaceres);
2825 if (error)
2826 goto out_trans_abort;
2827
2828 /*
2829 * If we're renaming one or more directories across different parents,
2830 * update the respective ".." entries (and link counts) to match the new
2831 * parents.
2832 */
2833 if (dp1 != dp2) {
2834 dp2_flags = XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
2835
2836 if (S_ISDIR(VFS_I(ip2)->i_mode)) {
2837 error = xfs_dir_replace(tp, ip2, &xfs_name_dotdot,
2838 dp1->i_ino, spaceres);
2839 if (error)
2840 goto out_trans_abort;
2841
2842 /* transfer ip2 ".." reference to dp1 */
2843 if (!S_ISDIR(VFS_I(ip1)->i_mode)) {
2844 error = xfs_droplink(tp, dp2);
2845 if (error)
2846 goto out_trans_abort;
2847 xfs_bumplink(tp, dp1);
2848 }
2849
2850 /*
2851 * Although ip1 isn't changed here, userspace needs
2852 * to be warned about the change, so that applications
2853 * relying on it (like backup ones), will properly
2854 * notify the change
2855 */
2856 ip1_flags |= XFS_ICHGTIME_CHG;
2857 ip2_flags |= XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
2858 }
2859
2860 if (S_ISDIR(VFS_I(ip1)->i_mode)) {
2861 error = xfs_dir_replace(tp, ip1, &xfs_name_dotdot,
2862 dp2->i_ino, spaceres);
2863 if (error)
2864 goto out_trans_abort;
2865
2866 /* transfer ip1 ".." reference to dp2 */
2867 if (!S_ISDIR(VFS_I(ip2)->i_mode)) {
2868 error = xfs_droplink(tp, dp1);
2869 if (error)
2870 goto out_trans_abort;
2871 xfs_bumplink(tp, dp2);
2872 }
2873
2874 /*
2875 * Although ip2 isn't changed here, userspace needs
2876 * to be warned about the change, so that applications
2877 * relying on it (like backup ones), will properly
2878 * notify the change
2879 */
2880 ip1_flags |= XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
2881 ip2_flags |= XFS_ICHGTIME_CHG;
2882 }
2883 }
2884
2885 if (ip1_flags) {
2886 xfs_trans_ichgtime(tp, ip1, ip1_flags);
2887 xfs_trans_log_inode(tp, ip1, XFS_ILOG_CORE);
2888 }
2889 if (ip2_flags) {
2890 xfs_trans_ichgtime(tp, ip2, ip2_flags);
2891 xfs_trans_log_inode(tp, ip2, XFS_ILOG_CORE);
2892 }
2893 if (dp2_flags) {
2894 xfs_trans_ichgtime(tp, dp2, dp2_flags);
2895 xfs_trans_log_inode(tp, dp2, XFS_ILOG_CORE);
2896 }
2897 xfs_trans_ichgtime(tp, dp1, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2898 xfs_trans_log_inode(tp, dp1, XFS_ILOG_CORE);
2899
2900 /*
2901 * Inform our hook clients that we've finished an exchange operation as
2902 * follows: removed the source and target files from their directories;
2903 * added the target to the source directory; and added the source to
2904 * the target directory. All inodes are locked, so it's ok to model a
2905 * rename this way so long as we say we deleted entries before we add
2906 * new ones.
2907 */
2908 xfs_dir_update_hook(dp1, ip1, -1, name1);
2909 xfs_dir_update_hook(dp2, ip2, -1, name2);
2910 xfs_dir_update_hook(dp1, ip2, 1, name1);
2911 xfs_dir_update_hook(dp2, ip1, 1, name2);
2912
2913 return xfs_finish_rename(tp);
2914
2915out_trans_abort:
2916 xfs_trans_cancel(tp);
2917 return error;
2918}
2919
2920/*
2921 * xfs_rename_alloc_whiteout()
2922 *
2923 * Return a referenced, unlinked, unlocked inode that can be used as a
2924 * whiteout in a rename transaction. We use a tmpfile inode here so that if we
2925 * crash between allocating the inode and linking it into the rename transaction
2926 * recovery will free the inode and we won't leak it.
2927 */
2928static int
2929xfs_rename_alloc_whiteout(
2930 struct mnt_idmap *idmap,
2931 struct xfs_name *src_name,
2932 struct xfs_inode *dp,
2933 struct xfs_inode **wip)
2934{
2935 struct xfs_inode *tmpfile;
2936 struct qstr name;
2937 int error;
2938
2939 error = xfs_create_tmpfile(idmap, dp, S_IFCHR | WHITEOUT_MODE,
2940 &tmpfile);
2941 if (error)
2942 return error;
2943
2944 name.name = src_name->name;
2945 name.len = src_name->len;
2946 error = xfs_inode_init_security(VFS_I(tmpfile), VFS_I(dp), &name);
2947 if (error) {
2948 xfs_finish_inode_setup(tmpfile);
2949 xfs_irele(tmpfile);
2950 return error;
2951 }
2952
2953 /*
2954 * Prepare the tmpfile inode as if it were created through the VFS.
2955 * Complete the inode setup and flag it as linkable. nlink is already
2956 * zero, so we can skip the drop_nlink.
2957 */
2958 xfs_setup_iops(tmpfile);
2959 xfs_finish_inode_setup(tmpfile);
2960 VFS_I(tmpfile)->i_state |= I_LINKABLE;
2961
2962 *wip = tmpfile;
2963 return 0;
2964}
2965
2966/*
2967 * xfs_rename
2968 */
2969int
2970xfs_rename(
2971 struct mnt_idmap *idmap,
2972 struct xfs_inode *src_dp,
2973 struct xfs_name *src_name,
2974 struct xfs_inode *src_ip,
2975 struct xfs_inode *target_dp,
2976 struct xfs_name *target_name,
2977 struct xfs_inode *target_ip,
2978 unsigned int flags)
2979{
2980 struct xfs_mount *mp = src_dp->i_mount;
2981 struct xfs_trans *tp;
2982 struct xfs_inode *wip = NULL; /* whiteout inode */
2983 struct xfs_inode *inodes[__XFS_SORT_INODES];
2984 int i;
2985 int num_inodes = __XFS_SORT_INODES;
2986 bool new_parent = (src_dp != target_dp);
2987 bool src_is_directory = S_ISDIR(VFS_I(src_ip)->i_mode);
2988 int spaceres;
2989 bool retried = false;
2990 int error, nospace_error = 0;
2991
2992 trace_xfs_rename(src_dp, target_dp, src_name, target_name);
2993
2994 if ((flags & RENAME_EXCHANGE) && !target_ip)
2995 return -EINVAL;
2996
2997 /*
2998 * If we are doing a whiteout operation, allocate the whiteout inode
2999 * we will be placing at the target and ensure the type is set
3000 * appropriately.
3001 */
3002 if (flags & RENAME_WHITEOUT) {
3003 error = xfs_rename_alloc_whiteout(idmap, src_name,
3004 target_dp, &wip);
3005 if (error)
3006 return error;
3007
3008 /* setup target dirent info as whiteout */
3009 src_name->type = XFS_DIR3_FT_CHRDEV;
3010 }
3011
3012 xfs_sort_for_rename(src_dp, target_dp, src_ip, target_ip, wip,
3013 inodes, &num_inodes);
3014
3015retry:
3016 nospace_error = 0;
3017 spaceres = XFS_RENAME_SPACE_RES(mp, target_name->len);
3018 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_rename, spaceres, 0, 0, &tp);
3019 if (error == -ENOSPC) {
3020 nospace_error = error;
3021 spaceres = 0;
3022 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_rename, 0, 0, 0,
3023 &tp);
3024 }
3025 if (error)
3026 goto out_release_wip;
3027
3028 /*
3029 * Attach the dquots to the inodes
3030 */
3031 error = xfs_qm_vop_rename_dqattach(inodes);
3032 if (error)
3033 goto out_trans_cancel;
3034
3035 /*
3036 * Lock all the participating inodes. Depending upon whether
3037 * the target_name exists in the target directory, and
3038 * whether the target directory is the same as the source
3039 * directory, we can lock from 2 to 5 inodes.
3040 */
3041 xfs_lock_inodes(inodes, num_inodes, XFS_ILOCK_EXCL);
3042
3043 /*
3044 * Join all the inodes to the transaction. From this point on,
3045 * we can rely on either trans_commit or trans_cancel to unlock
3046 * them.
3047 */
3048 xfs_trans_ijoin(tp, src_dp, XFS_ILOCK_EXCL);
3049 if (new_parent)
3050 xfs_trans_ijoin(tp, target_dp, XFS_ILOCK_EXCL);
3051 xfs_trans_ijoin(tp, src_ip, XFS_ILOCK_EXCL);
3052 if (target_ip)
3053 xfs_trans_ijoin(tp, target_ip, XFS_ILOCK_EXCL);
3054 if (wip)
3055 xfs_trans_ijoin(tp, wip, XFS_ILOCK_EXCL);
3056
3057 /*
3058 * If we are using project inheritance, we only allow renames
3059 * into our tree when the project IDs are the same; else the
3060 * tree quota mechanism would be circumvented.
3061 */
3062 if (unlikely((target_dp->i_diflags & XFS_DIFLAG_PROJINHERIT) &&
3063 target_dp->i_projid != src_ip->i_projid)) {
3064 error = -EXDEV;
3065 goto out_trans_cancel;
3066 }
3067
3068 /* RENAME_EXCHANGE is unique from here on. */
3069 if (flags & RENAME_EXCHANGE)
3070 return xfs_cross_rename(tp, src_dp, src_name, src_ip,
3071 target_dp, target_name, target_ip,
3072 spaceres);
3073
3074 /*
3075 * Try to reserve quota to handle an expansion of the target directory.
3076 * We'll allow the rename to continue in reservationless mode if we hit
3077 * a space usage constraint. If we trigger reservationless mode, save
3078 * the errno if there isn't any free space in the target directory.
3079 */
3080 if (spaceres != 0) {
3081 error = xfs_trans_reserve_quota_nblks(tp, target_dp, spaceres,
3082 0, false);
3083 if (error == -EDQUOT || error == -ENOSPC) {
3084 if (!retried) {
3085 xfs_trans_cancel(tp);
3086 xfs_blockgc_free_quota(target_dp, 0);
3087 retried = true;
3088 goto retry;
3089 }
3090
3091 nospace_error = error;
3092 spaceres = 0;
3093 error = 0;
3094 }
3095 if (error)
3096 goto out_trans_cancel;
3097 }
3098
3099 /*
3100 * Check for expected errors before we dirty the transaction
3101 * so we can return an error without a transaction abort.
3102 */
3103 if (target_ip == NULL) {
3104 /*
3105 * If there's no space reservation, check the entry will
3106 * fit before actually inserting it.
3107 */
3108 if (!spaceres) {
3109 error = xfs_dir_canenter(tp, target_dp, target_name);
3110 if (error)
3111 goto out_trans_cancel;
3112 }
3113 } else {
3114 /*
3115 * If target exists and it's a directory, check that whether
3116 * it can be destroyed.
3117 */
3118 if (S_ISDIR(VFS_I(target_ip)->i_mode) &&
3119 (!xfs_dir_isempty(target_ip) ||
3120 (VFS_I(target_ip)->i_nlink > 2))) {
3121 error = -EEXIST;
3122 goto out_trans_cancel;
3123 }
3124 }
3125
3126 /*
3127 * Lock the AGI buffers we need to handle bumping the nlink of the
3128 * whiteout inode off the unlinked list and to handle dropping the
3129 * nlink of the target inode. Per locking order rules, do this in
3130 * increasing AG order and before directory block allocation tries to
3131 * grab AGFs because we grab AGIs before AGFs.
3132 *
3133 * The (vfs) caller must ensure that if src is a directory then
3134 * target_ip is either null or an empty directory.
3135 */
3136 for (i = 0; i < num_inodes && inodes[i] != NULL; i++) {
3137 if (inodes[i] == wip ||
3138 (inodes[i] == target_ip &&
3139 (VFS_I(target_ip)->i_nlink == 1 || src_is_directory))) {
3140 struct xfs_perag *pag;
3141 struct xfs_buf *bp;
3142
3143 pag = xfs_perag_get(mp,
3144 XFS_INO_TO_AGNO(mp, inodes[i]->i_ino));
3145 error = xfs_read_agi(pag, tp, &bp);
3146 xfs_perag_put(pag);
3147 if (error)
3148 goto out_trans_cancel;
3149 }
3150 }
3151
3152 /*
3153 * Directory entry creation below may acquire the AGF. Remove
3154 * the whiteout from the unlinked list first to preserve correct
3155 * AGI/AGF locking order. This dirties the transaction so failures
3156 * after this point will abort and log recovery will clean up the
3157 * mess.
3158 *
3159 * For whiteouts, we need to bump the link count on the whiteout
3160 * inode. After this point, we have a real link, clear the tmpfile
3161 * state flag from the inode so it doesn't accidentally get misused
3162 * in future.
3163 */
3164 if (wip) {
3165 struct xfs_perag *pag;
3166
3167 ASSERT(VFS_I(wip)->i_nlink == 0);
3168
3169 pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, wip->i_ino));
3170 error = xfs_iunlink_remove(tp, pag, wip);
3171 xfs_perag_put(pag);
3172 if (error)
3173 goto out_trans_cancel;
3174
3175 xfs_bumplink(tp, wip);
3176 VFS_I(wip)->i_state &= ~I_LINKABLE;
3177 }
3178
3179 /*
3180 * Set up the target.
3181 */
3182 if (target_ip == NULL) {
3183 /*
3184 * If target does not exist and the rename crosses
3185 * directories, adjust the target directory link count
3186 * to account for the ".." reference from the new entry.
3187 */
3188 error = xfs_dir_createname(tp, target_dp, target_name,
3189 src_ip->i_ino, spaceres);
3190 if (error)
3191 goto out_trans_cancel;
3192
3193 xfs_trans_ichgtime(tp, target_dp,
3194 XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
3195
3196 if (new_parent && src_is_directory) {
3197 xfs_bumplink(tp, target_dp);
3198 }
3199 } else { /* target_ip != NULL */
3200 /*
3201 * Link the source inode under the target name.
3202 * If the source inode is a directory and we are moving
3203 * it across directories, its ".." entry will be
3204 * inconsistent until we replace that down below.
3205 *
3206 * In case there is already an entry with the same
3207 * name at the destination directory, remove it first.
3208 */
3209 error = xfs_dir_replace(tp, target_dp, target_name,
3210 src_ip->i_ino, spaceres);
3211 if (error)
3212 goto out_trans_cancel;
3213
3214 xfs_trans_ichgtime(tp, target_dp,
3215 XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
3216
3217 /*
3218 * Decrement the link count on the target since the target
3219 * dir no longer points to it.
3220 */
3221 error = xfs_droplink(tp, target_ip);
3222 if (error)
3223 goto out_trans_cancel;
3224
3225 if (src_is_directory) {
3226 /*
3227 * Drop the link from the old "." entry.
3228 */
3229 error = xfs_droplink(tp, target_ip);
3230 if (error)
3231 goto out_trans_cancel;
3232 }
3233 } /* target_ip != NULL */
3234
3235 /*
3236 * Remove the source.
3237 */
3238 if (new_parent && src_is_directory) {
3239 /*
3240 * Rewrite the ".." entry to point to the new
3241 * directory.
3242 */
3243 error = xfs_dir_replace(tp, src_ip, &xfs_name_dotdot,
3244 target_dp->i_ino, spaceres);
3245 ASSERT(error != -EEXIST);
3246 if (error)
3247 goto out_trans_cancel;
3248 }
3249
3250 /*
3251 * We always want to hit the ctime on the source inode.
3252 *
3253 * This isn't strictly required by the standards since the source
3254 * inode isn't really being changed, but old unix file systems did
3255 * it and some incremental backup programs won't work without it.
3256 */
3257 xfs_trans_ichgtime(tp, src_ip, XFS_ICHGTIME_CHG);
3258 xfs_trans_log_inode(tp, src_ip, XFS_ILOG_CORE);
3259
3260 /*
3261 * Adjust the link count on src_dp. This is necessary when
3262 * renaming a directory, either within one parent when
3263 * the target existed, or across two parent directories.
3264 */
3265 if (src_is_directory && (new_parent || target_ip != NULL)) {
3266
3267 /*
3268 * Decrement link count on src_directory since the
3269 * entry that's moved no longer points to it.
3270 */
3271 error = xfs_droplink(tp, src_dp);
3272 if (error)
3273 goto out_trans_cancel;
3274 }
3275
3276 /*
3277 * For whiteouts, we only need to update the source dirent with the
3278 * inode number of the whiteout inode rather than removing it
3279 * altogether.
3280 */
3281 if (wip)
3282 error = xfs_dir_replace(tp, src_dp, src_name, wip->i_ino,
3283 spaceres);
3284 else
3285 error = xfs_dir_removename(tp, src_dp, src_name, src_ip->i_ino,
3286 spaceres);
3287
3288 if (error)
3289 goto out_trans_cancel;
3290
3291 xfs_trans_ichgtime(tp, src_dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
3292 xfs_trans_log_inode(tp, src_dp, XFS_ILOG_CORE);
3293 if (new_parent)
3294 xfs_trans_log_inode(tp, target_dp, XFS_ILOG_CORE);
3295
3296 /*
3297 * Inform our hook clients that we've finished a rename operation as
3298 * follows: removed the source and target files from their directories;
3299 * that we've added the source to the target directory; and finally
3300 * that we've added the whiteout, if there was one. All inodes are
3301 * locked, so it's ok to model a rename this way so long as we say we
3302 * deleted entries before we add new ones.
3303 */
3304 if (target_ip)
3305 xfs_dir_update_hook(target_dp, target_ip, -1, target_name);
3306 xfs_dir_update_hook(src_dp, src_ip, -1, src_name);
3307 xfs_dir_update_hook(target_dp, src_ip, 1, target_name);
3308 if (wip)
3309 xfs_dir_update_hook(src_dp, wip, 1, src_name);
3310
3311 error = xfs_finish_rename(tp);
3312 if (wip)
3313 xfs_irele(wip);
3314 return error;
3315
3316out_trans_cancel:
3317 xfs_trans_cancel(tp);
3318out_release_wip:
3319 if (wip)
3320 xfs_irele(wip);
3321 if (error == -ENOSPC && nospace_error)
3322 error = nospace_error;
3323 return error;
3324}
3325
3326static int
3327xfs_iflush(
3328 struct xfs_inode *ip,
3329 struct xfs_buf *bp)
3330{
3331 struct xfs_inode_log_item *iip = ip->i_itemp;
3332 struct xfs_dinode *dip;
3333 struct xfs_mount *mp = ip->i_mount;
3334 int error;
3335
3336 xfs_assert_ilocked(ip, XFS_ILOCK_EXCL | XFS_ILOCK_SHARED);
3337 ASSERT(xfs_iflags_test(ip, XFS_IFLUSHING));
3338 ASSERT(ip->i_df.if_format != XFS_DINODE_FMT_BTREE ||
3339 ip->i_df.if_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK));
3340 ASSERT(iip->ili_item.li_buf == bp);
3341
3342 dip = xfs_buf_offset(bp, ip->i_imap.im_boffset);
3343
3344 /*
3345 * We don't flush the inode if any of the following checks fail, but we
3346 * do still update the log item and attach to the backing buffer as if
3347 * the flush happened. This is a formality to facilitate predictable
3348 * error handling as the caller will shutdown and fail the buffer.
3349 */
3350 error = -EFSCORRUPTED;
3351 if (XFS_TEST_ERROR(dip->di_magic != cpu_to_be16(XFS_DINODE_MAGIC),
3352 mp, XFS_ERRTAG_IFLUSH_1)) {
3353 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3354 "%s: Bad inode %llu magic number 0x%x, ptr "PTR_FMT,
3355 __func__, ip->i_ino, be16_to_cpu(dip->di_magic), dip);
3356 goto flush_out;
3357 }
3358 if (S_ISREG(VFS_I(ip)->i_mode)) {
3359 if (XFS_TEST_ERROR(
3360 ip->i_df.if_format != XFS_DINODE_FMT_EXTENTS &&
3361 ip->i_df.if_format != XFS_DINODE_FMT_BTREE,
3362 mp, XFS_ERRTAG_IFLUSH_3)) {
3363 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3364 "%s: Bad regular inode %llu, ptr "PTR_FMT,
3365 __func__, ip->i_ino, ip);
3366 goto flush_out;
3367 }
3368 } else if (S_ISDIR(VFS_I(ip)->i_mode)) {
3369 if (XFS_TEST_ERROR(
3370 ip->i_df.if_format != XFS_DINODE_FMT_EXTENTS &&
3371 ip->i_df.if_format != XFS_DINODE_FMT_BTREE &&
3372 ip->i_df.if_format != XFS_DINODE_FMT_LOCAL,
3373 mp, XFS_ERRTAG_IFLUSH_4)) {
3374 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3375 "%s: Bad directory inode %llu, ptr "PTR_FMT,
3376 __func__, ip->i_ino, ip);
3377 goto flush_out;
3378 }
3379 }
3380 if (XFS_TEST_ERROR(ip->i_df.if_nextents + xfs_ifork_nextents(&ip->i_af) >
3381 ip->i_nblocks, mp, XFS_ERRTAG_IFLUSH_5)) {
3382 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3383 "%s: detected corrupt incore inode %llu, "
3384 "total extents = %llu nblocks = %lld, ptr "PTR_FMT,
3385 __func__, ip->i_ino,
3386 ip->i_df.if_nextents + xfs_ifork_nextents(&ip->i_af),
3387 ip->i_nblocks, ip);
3388 goto flush_out;
3389 }
3390 if (XFS_TEST_ERROR(ip->i_forkoff > mp->m_sb.sb_inodesize,
3391 mp, XFS_ERRTAG_IFLUSH_6)) {
3392 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3393 "%s: bad inode %llu, forkoff 0x%x, ptr "PTR_FMT,
3394 __func__, ip->i_ino, ip->i_forkoff, ip);
3395 goto flush_out;
3396 }
3397
3398 /*
3399 * Inode item log recovery for v2 inodes are dependent on the flushiter
3400 * count for correct sequencing. We bump the flush iteration count so
3401 * we can detect flushes which postdate a log record during recovery.
3402 * This is redundant as we now log every change and hence this can't
3403 * happen but we need to still do it to ensure backwards compatibility
3404 * with old kernels that predate logging all inode changes.
3405 */
3406 if (!xfs_has_v3inodes(mp))
3407 ip->i_flushiter++;
3408
3409 /*
3410 * If there are inline format data / attr forks attached to this inode,
3411 * make sure they are not corrupt.
3412 */
3413 if (ip->i_df.if_format == XFS_DINODE_FMT_LOCAL &&
3414 xfs_ifork_verify_local_data(ip))
3415 goto flush_out;
3416 if (xfs_inode_has_attr_fork(ip) &&
3417 ip->i_af.if_format == XFS_DINODE_FMT_LOCAL &&
3418 xfs_ifork_verify_local_attr(ip))
3419 goto flush_out;
3420
3421 /*
3422 * Copy the dirty parts of the inode into the on-disk inode. We always
3423 * copy out the core of the inode, because if the inode is dirty at all
3424 * the core must be.
3425 */
3426 xfs_inode_to_disk(ip, dip, iip->ili_item.li_lsn);
3427
3428 /* Wrap, we never let the log put out DI_MAX_FLUSH */
3429 if (!xfs_has_v3inodes(mp)) {
3430 if (ip->i_flushiter == DI_MAX_FLUSH)
3431 ip->i_flushiter = 0;
3432 }
3433
3434 xfs_iflush_fork(ip, dip, iip, XFS_DATA_FORK);
3435 if (xfs_inode_has_attr_fork(ip))
3436 xfs_iflush_fork(ip, dip, iip, XFS_ATTR_FORK);
3437
3438 /*
3439 * We've recorded everything logged in the inode, so we'd like to clear
3440 * the ili_fields bits so we don't log and flush things unnecessarily.
3441 * However, we can't stop logging all this information until the data
3442 * we've copied into the disk buffer is written to disk. If we did we
3443 * might overwrite the copy of the inode in the log with all the data
3444 * after re-logging only part of it, and in the face of a crash we
3445 * wouldn't have all the data we need to recover.
3446 *
3447 * What we do is move the bits to the ili_last_fields field. When
3448 * logging the inode, these bits are moved back to the ili_fields field.
3449 * In the xfs_buf_inode_iodone() routine we clear ili_last_fields, since
3450 * we know that the information those bits represent is permanently on
3451 * disk. As long as the flush completes before the inode is logged
3452 * again, then both ili_fields and ili_last_fields will be cleared.
3453 */
3454 error = 0;
3455flush_out:
3456 spin_lock(&iip->ili_lock);
3457 iip->ili_last_fields = iip->ili_fields;
3458 iip->ili_fields = 0;
3459 iip->ili_fsync_fields = 0;
3460 spin_unlock(&iip->ili_lock);
3461
3462 /*
3463 * Store the current LSN of the inode so that we can tell whether the
3464 * item has moved in the AIL from xfs_buf_inode_iodone().
3465 */
3466 xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn,
3467 &iip->ili_item.li_lsn);
3468
3469 /* generate the checksum. */
3470 xfs_dinode_calc_crc(mp, dip);
3471 if (error)
3472 xfs_inode_mark_sick(ip, XFS_SICK_INO_CORE);
3473 return error;
3474}
3475
3476/*
3477 * Non-blocking flush of dirty inode metadata into the backing buffer.
3478 *
3479 * The caller must have a reference to the inode and hold the cluster buffer
3480 * locked. The function will walk across all the inodes on the cluster buffer it
3481 * can find and lock without blocking, and flush them to the cluster buffer.
3482 *
3483 * On successful flushing of at least one inode, the caller must write out the
3484 * buffer and release it. If no inodes are flushed, -EAGAIN will be returned and
3485 * the caller needs to release the buffer. On failure, the filesystem will be
3486 * shut down, the buffer will have been unlocked and released, and EFSCORRUPTED
3487 * will be returned.
3488 */
3489int
3490xfs_iflush_cluster(
3491 struct xfs_buf *bp)
3492{
3493 struct xfs_mount *mp = bp->b_mount;
3494 struct xfs_log_item *lip, *n;
3495 struct xfs_inode *ip;
3496 struct xfs_inode_log_item *iip;
3497 int clcount = 0;
3498 int error = 0;
3499
3500 /*
3501 * We must use the safe variant here as on shutdown xfs_iflush_abort()
3502 * will remove itself from the list.
3503 */
3504 list_for_each_entry_safe(lip, n, &bp->b_li_list, li_bio_list) {
3505 iip = (struct xfs_inode_log_item *)lip;
3506 ip = iip->ili_inode;
3507
3508 /*
3509 * Quick and dirty check to avoid locks if possible.
3510 */
3511 if (__xfs_iflags_test(ip, XFS_IRECLAIM | XFS_IFLUSHING))
3512 continue;
3513 if (xfs_ipincount(ip))
3514 continue;
3515
3516 /*
3517 * The inode is still attached to the buffer, which means it is
3518 * dirty but reclaim might try to grab it. Check carefully for
3519 * that, and grab the ilock while still holding the i_flags_lock
3520 * to guarantee reclaim will not be able to reclaim this inode
3521 * once we drop the i_flags_lock.
3522 */
3523 spin_lock(&ip->i_flags_lock);
3524 ASSERT(!__xfs_iflags_test(ip, XFS_ISTALE));
3525 if (__xfs_iflags_test(ip, XFS_IRECLAIM | XFS_IFLUSHING)) {
3526 spin_unlock(&ip->i_flags_lock);
3527 continue;
3528 }
3529
3530 /*
3531 * ILOCK will pin the inode against reclaim and prevent
3532 * concurrent transactions modifying the inode while we are
3533 * flushing the inode. If we get the lock, set the flushing
3534 * state before we drop the i_flags_lock.
3535 */
3536 if (!xfs_ilock_nowait(ip, XFS_ILOCK_SHARED)) {
3537 spin_unlock(&ip->i_flags_lock);
3538 continue;
3539 }
3540 __xfs_iflags_set(ip, XFS_IFLUSHING);
3541 spin_unlock(&ip->i_flags_lock);
3542
3543 /*
3544 * Abort flushing this inode if we are shut down because the
3545 * inode may not currently be in the AIL. This can occur when
3546 * log I/O failure unpins the inode without inserting into the
3547 * AIL, leaving a dirty/unpinned inode attached to the buffer
3548 * that otherwise looks like it should be flushed.
3549 */
3550 if (xlog_is_shutdown(mp->m_log)) {
3551 xfs_iunpin_wait(ip);
3552 xfs_iflush_abort(ip);
3553 xfs_iunlock(ip, XFS_ILOCK_SHARED);
3554 error = -EIO;
3555 continue;
3556 }
3557
3558 /* don't block waiting on a log force to unpin dirty inodes */
3559 if (xfs_ipincount(ip)) {
3560 xfs_iflags_clear(ip, XFS_IFLUSHING);
3561 xfs_iunlock(ip, XFS_ILOCK_SHARED);
3562 continue;
3563 }
3564
3565 if (!xfs_inode_clean(ip))
3566 error = xfs_iflush(ip, bp);
3567 else
3568 xfs_iflags_clear(ip, XFS_IFLUSHING);
3569 xfs_iunlock(ip, XFS_ILOCK_SHARED);
3570 if (error)
3571 break;
3572 clcount++;
3573 }
3574
3575 if (error) {
3576 /*
3577 * Shutdown first so we kill the log before we release this
3578 * buffer. If it is an INODE_ALLOC buffer and pins the tail
3579 * of the log, failing it before the _log_ is shut down can
3580 * result in the log tail being moved forward in the journal
3581 * on disk because log writes can still be taking place. Hence
3582 * unpinning the tail will allow the ICREATE intent to be
3583 * removed from the log an recovery will fail with uninitialised
3584 * inode cluster buffers.
3585 */
3586 xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
3587 bp->b_flags |= XBF_ASYNC;
3588 xfs_buf_ioend_fail(bp);
3589 return error;
3590 }
3591
3592 if (!clcount)
3593 return -EAGAIN;
3594
3595 XFS_STATS_INC(mp, xs_icluster_flushcnt);
3596 XFS_STATS_ADD(mp, xs_icluster_flushinode, clcount);
3597 return 0;
3598
3599}
3600
3601/* Release an inode. */
3602void
3603xfs_irele(
3604 struct xfs_inode *ip)
3605{
3606 trace_xfs_irele(ip, _RET_IP_);
3607 iput(VFS_I(ip));
3608}
3609
3610/*
3611 * Ensure all commited transactions touching the inode are written to the log.
3612 */
3613int
3614xfs_log_force_inode(
3615 struct xfs_inode *ip)
3616{
3617 xfs_csn_t seq = 0;
3618
3619 xfs_ilock(ip, XFS_ILOCK_SHARED);
3620 if (xfs_ipincount(ip))
3621 seq = ip->i_itemp->ili_commit_seq;
3622 xfs_iunlock(ip, XFS_ILOCK_SHARED);
3623
3624 if (!seq)
3625 return 0;
3626 return xfs_log_force_seq(ip->i_mount, seq, XFS_LOG_SYNC, NULL);
3627}
3628
3629/*
3630 * Grab the exclusive iolock for a data copy from src to dest, making sure to
3631 * abide vfs locking order (lowest pointer value goes first) and breaking the
3632 * layout leases before proceeding. The loop is needed because we cannot call
3633 * the blocking break_layout() with the iolocks held, and therefore have to
3634 * back out both locks.
3635 */
3636static int
3637xfs_iolock_two_inodes_and_break_layout(
3638 struct inode *src,
3639 struct inode *dest)
3640{
3641 int error;
3642
3643 if (src > dest)
3644 swap(src, dest);
3645
3646retry:
3647 /* Wait to break both inodes' layouts before we start locking. */
3648 error = break_layout(src, true);
3649 if (error)
3650 return error;
3651 if (src != dest) {
3652 error = break_layout(dest, true);
3653 if (error)
3654 return error;
3655 }
3656
3657 /* Lock one inode and make sure nobody got in and leased it. */
3658 inode_lock(src);
3659 error = break_layout(src, false);
3660 if (error) {
3661 inode_unlock(src);
3662 if (error == -EWOULDBLOCK)
3663 goto retry;
3664 return error;
3665 }
3666
3667 if (src == dest)
3668 return 0;
3669
3670 /* Lock the other inode and make sure nobody got in and leased it. */
3671 inode_lock_nested(dest, I_MUTEX_NONDIR2);
3672 error = break_layout(dest, false);
3673 if (error) {
3674 inode_unlock(src);
3675 inode_unlock(dest);
3676 if (error == -EWOULDBLOCK)
3677 goto retry;
3678 return error;
3679 }
3680
3681 return 0;
3682}
3683
3684static int
3685xfs_mmaplock_two_inodes_and_break_dax_layout(
3686 struct xfs_inode *ip1,
3687 struct xfs_inode *ip2)
3688{
3689 int error;
3690 bool retry;
3691 struct page *page;
3692
3693 if (ip1->i_ino > ip2->i_ino)
3694 swap(ip1, ip2);
3695
3696again:
3697 retry = false;
3698 /* Lock the first inode */
3699 xfs_ilock(ip1, XFS_MMAPLOCK_EXCL);
3700 error = xfs_break_dax_layouts(VFS_I(ip1), &retry);
3701 if (error || retry) {
3702 xfs_iunlock(ip1, XFS_MMAPLOCK_EXCL);
3703 if (error == 0 && retry)
3704 goto again;
3705 return error;
3706 }
3707
3708 if (ip1 == ip2)
3709 return 0;
3710
3711 /* Nested lock the second inode */
3712 xfs_ilock(ip2, xfs_lock_inumorder(XFS_MMAPLOCK_EXCL, 1));
3713 /*
3714 * We cannot use xfs_break_dax_layouts() directly here because it may
3715 * need to unlock & lock the XFS_MMAPLOCK_EXCL which is not suitable
3716 * for this nested lock case.
3717 */
3718 page = dax_layout_busy_page(VFS_I(ip2)->i_mapping);
3719 if (page && page_ref_count(page) != 1) {
3720 xfs_iunlock(ip2, XFS_MMAPLOCK_EXCL);
3721 xfs_iunlock(ip1, XFS_MMAPLOCK_EXCL);
3722 goto again;
3723 }
3724
3725 return 0;
3726}
3727
3728/*
3729 * Lock two inodes so that userspace cannot initiate I/O via file syscalls or
3730 * mmap activity.
3731 */
3732int
3733xfs_ilock2_io_mmap(
3734 struct xfs_inode *ip1,
3735 struct xfs_inode *ip2)
3736{
3737 int ret;
3738
3739 ret = xfs_iolock_two_inodes_and_break_layout(VFS_I(ip1), VFS_I(ip2));
3740 if (ret)
3741 return ret;
3742
3743 if (IS_DAX(VFS_I(ip1)) && IS_DAX(VFS_I(ip2))) {
3744 ret = xfs_mmaplock_two_inodes_and_break_dax_layout(ip1, ip2);
3745 if (ret) {
3746 inode_unlock(VFS_I(ip2));
3747 if (ip1 != ip2)
3748 inode_unlock(VFS_I(ip1));
3749 return ret;
3750 }
3751 } else
3752 filemap_invalidate_lock_two(VFS_I(ip1)->i_mapping,
3753 VFS_I(ip2)->i_mapping);
3754
3755 return 0;
3756}
3757
3758/* Unlock both inodes to allow IO and mmap activity. */
3759void
3760xfs_iunlock2_io_mmap(
3761 struct xfs_inode *ip1,
3762 struct xfs_inode *ip2)
3763{
3764 if (IS_DAX(VFS_I(ip1)) && IS_DAX(VFS_I(ip2))) {
3765 xfs_iunlock(ip2, XFS_MMAPLOCK_EXCL);
3766 if (ip1 != ip2)
3767 xfs_iunlock(ip1, XFS_MMAPLOCK_EXCL);
3768 } else
3769 filemap_invalidate_unlock_two(VFS_I(ip1)->i_mapping,
3770 VFS_I(ip2)->i_mapping);
3771
3772 inode_unlock(VFS_I(ip2));
3773 if (ip1 != ip2)
3774 inode_unlock(VFS_I(ip1));
3775}
3776
3777/* Drop the MMAPLOCK and the IOLOCK after a remap completes. */
3778void
3779xfs_iunlock2_remapping(
3780 struct xfs_inode *ip1,
3781 struct xfs_inode *ip2)
3782{
3783 xfs_iflags_clear(ip1, XFS_IREMAPPING);
3784
3785 if (ip1 != ip2)
3786 xfs_iunlock(ip1, XFS_MMAPLOCK_SHARED);
3787 xfs_iunlock(ip2, XFS_MMAPLOCK_EXCL);
3788
3789 if (ip1 != ip2)
3790 inode_unlock_shared(VFS_I(ip1));
3791 inode_unlock(VFS_I(ip2));
3792}
3793
3794/*
3795 * Reload the incore inode list for this inode. Caller should ensure that
3796 * the link count cannot change, either by taking ILOCK_SHARED or otherwise
3797 * preventing other threads from executing.
3798 */
3799int
3800xfs_inode_reload_unlinked_bucket(
3801 struct xfs_trans *tp,
3802 struct xfs_inode *ip)
3803{
3804 struct xfs_mount *mp = tp->t_mountp;
3805 struct xfs_buf *agibp;
3806 struct xfs_agi *agi;
3807 struct xfs_perag *pag;
3808 xfs_agnumber_t agno = XFS_INO_TO_AGNO(mp, ip->i_ino);
3809 xfs_agino_t agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
3810 xfs_agino_t prev_agino, next_agino;
3811 unsigned int bucket;
3812 bool foundit = false;
3813 int error;
3814
3815 /* Grab the first inode in the list */
3816 pag = xfs_perag_get(mp, agno);
3817 error = xfs_ialloc_read_agi(pag, tp, &agibp);
3818 xfs_perag_put(pag);
3819 if (error)
3820 return error;
3821
3822 /*
3823 * We've taken ILOCK_SHARED and the AGI buffer lock to stabilize the
3824 * incore unlinked list pointers for this inode. Check once more to
3825 * see if we raced with anyone else to reload the unlinked list.
3826 */
3827 if (!xfs_inode_unlinked_incomplete(ip)) {
3828 foundit = true;
3829 goto out_agibp;
3830 }
3831
3832 bucket = agino % XFS_AGI_UNLINKED_BUCKETS;
3833 agi = agibp->b_addr;
3834
3835 trace_xfs_inode_reload_unlinked_bucket(ip);
3836
3837 xfs_info_ratelimited(mp,
3838 "Found unrecovered unlinked inode 0x%x in AG 0x%x. Initiating list recovery.",
3839 agino, agno);
3840
3841 prev_agino = NULLAGINO;
3842 next_agino = be32_to_cpu(agi->agi_unlinked[bucket]);
3843 while (next_agino != NULLAGINO) {
3844 struct xfs_inode *next_ip = NULL;
3845
3846 /* Found this caller's inode, set its backlink. */
3847 if (next_agino == agino) {
3848 next_ip = ip;
3849 next_ip->i_prev_unlinked = prev_agino;
3850 foundit = true;
3851 goto next_inode;
3852 }
3853
3854 /* Try in-memory lookup first. */
3855 next_ip = xfs_iunlink_lookup(pag, next_agino);
3856 if (next_ip)
3857 goto next_inode;
3858
3859 /* Inode not in memory, try reloading it. */
3860 error = xfs_iunlink_reload_next(tp, agibp, prev_agino,
3861 next_agino);
3862 if (error)
3863 break;
3864
3865 /* Grab the reloaded inode. */
3866 next_ip = xfs_iunlink_lookup(pag, next_agino);
3867 if (!next_ip) {
3868 /* No incore inode at all? We reloaded it... */
3869 ASSERT(next_ip != NULL);
3870 error = -EFSCORRUPTED;
3871 break;
3872 }
3873
3874next_inode:
3875 prev_agino = next_agino;
3876 next_agino = next_ip->i_next_unlinked;
3877 }
3878
3879out_agibp:
3880 xfs_trans_brelse(tp, agibp);
3881 /* Should have found this inode somewhere in the iunlinked bucket. */
3882 if (!error && !foundit)
3883 error = -EFSCORRUPTED;
3884 return error;
3885}
3886
3887/* Decide if this inode is missing its unlinked list and reload it. */
3888int
3889xfs_inode_reload_unlinked(
3890 struct xfs_inode *ip)
3891{
3892 struct xfs_trans *tp;
3893 int error;
3894
3895 error = xfs_trans_alloc_empty(ip->i_mount, &tp);
3896 if (error)
3897 return error;
3898
3899 xfs_ilock(ip, XFS_ILOCK_SHARED);
3900 if (xfs_inode_unlinked_incomplete(ip))
3901 error = xfs_inode_reload_unlinked_bucket(tp, ip);
3902 xfs_iunlock(ip, XFS_ILOCK_SHARED);
3903 xfs_trans_cancel(tp);
3904
3905 return error;
3906}
3907
3908/* Has this inode fork been zapped by repair? */
3909bool
3910xfs_ifork_zapped(
3911 const struct xfs_inode *ip,
3912 int whichfork)
3913{
3914 unsigned int datamask = 0;
3915
3916 switch (whichfork) {
3917 case XFS_DATA_FORK:
3918 switch (ip->i_vnode.i_mode & S_IFMT) {
3919 case S_IFDIR:
3920 datamask = XFS_SICK_INO_DIR_ZAPPED;
3921 break;
3922 case S_IFLNK:
3923 datamask = XFS_SICK_INO_SYMLINK_ZAPPED;
3924 break;
3925 }
3926 return ip->i_sick & (XFS_SICK_INO_BMBTD_ZAPPED | datamask);
3927 case XFS_ATTR_FORK:
3928 return ip->i_sick & XFS_SICK_INO_BMBTA_ZAPPED;
3929 default:
3930 return false;
3931 }
3932}
3933
3934/* Compute the number of data and realtime blocks used by a file. */
3935void
3936xfs_inode_count_blocks(
3937 struct xfs_trans *tp,
3938 struct xfs_inode *ip,
3939 xfs_filblks_t *dblocks,
3940 xfs_filblks_t *rblocks)
3941{
3942 struct xfs_ifork *ifp = xfs_ifork_ptr(ip, XFS_DATA_FORK);
3943
3944 *rblocks = 0;
3945 if (XFS_IS_REALTIME_INODE(ip))
3946 xfs_bmap_count_leaves(ifp, rblocks);
3947 *dblocks = ip->i_nblocks - *rblocks;
3948}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (c) 2000-2006 Silicon Graphics, Inc.
4 * All Rights Reserved.
5 */
6#include <linux/iversion.h>
7
8#include "xfs.h"
9#include "xfs_fs.h"
10#include "xfs_shared.h"
11#include "xfs_format.h"
12#include "xfs_log_format.h"
13#include "xfs_trans_resv.h"
14#include "xfs_mount.h"
15#include "xfs_defer.h"
16#include "xfs_inode.h"
17#include "xfs_dir2.h"
18#include "xfs_attr.h"
19#include "xfs_trans_space.h"
20#include "xfs_trans.h"
21#include "xfs_buf_item.h"
22#include "xfs_inode_item.h"
23#include "xfs_ialloc.h"
24#include "xfs_bmap.h"
25#include "xfs_bmap_util.h"
26#include "xfs_errortag.h"
27#include "xfs_error.h"
28#include "xfs_quota.h"
29#include "xfs_filestream.h"
30#include "xfs_trace.h"
31#include "xfs_icache.h"
32#include "xfs_symlink.h"
33#include "xfs_trans_priv.h"
34#include "xfs_log.h"
35#include "xfs_bmap_btree.h"
36#include "xfs_reflink.h"
37#include "xfs_ag.h"
38
39kmem_zone_t *xfs_inode_zone;
40
41/*
42 * Used in xfs_itruncate_extents(). This is the maximum number of extents
43 * freed from a file in a single transaction.
44 */
45#define XFS_ITRUNC_MAX_EXTENTS 2
46
47STATIC int xfs_iunlink(struct xfs_trans *, struct xfs_inode *);
48STATIC int xfs_iunlink_remove(struct xfs_trans *tp, struct xfs_perag *pag,
49 struct xfs_inode *);
50
51/*
52 * helper function to extract extent size hint from inode
53 */
54xfs_extlen_t
55xfs_get_extsz_hint(
56 struct xfs_inode *ip)
57{
58 /*
59 * No point in aligning allocations if we need to COW to actually
60 * write to them.
61 */
62 if (xfs_is_always_cow_inode(ip))
63 return 0;
64 if ((ip->i_diflags & XFS_DIFLAG_EXTSIZE) && ip->i_extsize)
65 return ip->i_extsize;
66 if (XFS_IS_REALTIME_INODE(ip))
67 return ip->i_mount->m_sb.sb_rextsize;
68 return 0;
69}
70
71/*
72 * Helper function to extract CoW extent size hint from inode.
73 * Between the extent size hint and the CoW extent size hint, we
74 * return the greater of the two. If the value is zero (automatic),
75 * use the default size.
76 */
77xfs_extlen_t
78xfs_get_cowextsz_hint(
79 struct xfs_inode *ip)
80{
81 xfs_extlen_t a, b;
82
83 a = 0;
84 if (ip->i_diflags2 & XFS_DIFLAG2_COWEXTSIZE)
85 a = ip->i_cowextsize;
86 b = xfs_get_extsz_hint(ip);
87
88 a = max(a, b);
89 if (a == 0)
90 return XFS_DEFAULT_COWEXTSZ_HINT;
91 return a;
92}
93
94/*
95 * These two are wrapper routines around the xfs_ilock() routine used to
96 * centralize some grungy code. They are used in places that wish to lock the
97 * inode solely for reading the extents. The reason these places can't just
98 * call xfs_ilock(ip, XFS_ILOCK_SHARED) is that the inode lock also guards to
99 * bringing in of the extents from disk for a file in b-tree format. If the
100 * inode is in b-tree format, then we need to lock the inode exclusively until
101 * the extents are read in. Locking it exclusively all the time would limit
102 * our parallelism unnecessarily, though. What we do instead is check to see
103 * if the extents have been read in yet, and only lock the inode exclusively
104 * if they have not.
105 *
106 * The functions return a value which should be given to the corresponding
107 * xfs_iunlock() call.
108 */
109uint
110xfs_ilock_data_map_shared(
111 struct xfs_inode *ip)
112{
113 uint lock_mode = XFS_ILOCK_SHARED;
114
115 if (xfs_need_iread_extents(&ip->i_df))
116 lock_mode = XFS_ILOCK_EXCL;
117 xfs_ilock(ip, lock_mode);
118 return lock_mode;
119}
120
121uint
122xfs_ilock_attr_map_shared(
123 struct xfs_inode *ip)
124{
125 uint lock_mode = XFS_ILOCK_SHARED;
126
127 if (ip->i_afp && xfs_need_iread_extents(ip->i_afp))
128 lock_mode = XFS_ILOCK_EXCL;
129 xfs_ilock(ip, lock_mode);
130 return lock_mode;
131}
132
133/*
134 * In addition to i_rwsem in the VFS inode, the xfs inode contains 2
135 * multi-reader locks: i_mmap_lock and the i_lock. This routine allows
136 * various combinations of the locks to be obtained.
137 *
138 * The 3 locks should always be ordered so that the IO lock is obtained first,
139 * the mmap lock second and the ilock last in order to prevent deadlock.
140 *
141 * Basic locking order:
142 *
143 * i_rwsem -> i_mmap_lock -> page_lock -> i_ilock
144 *
145 * mmap_lock locking order:
146 *
147 * i_rwsem -> page lock -> mmap_lock
148 * mmap_lock -> i_mmap_lock -> page_lock
149 *
150 * The difference in mmap_lock locking order mean that we cannot hold the
151 * i_mmap_lock over syscall based read(2)/write(2) based IO. These IO paths can
152 * fault in pages during copy in/out (for buffered IO) or require the mmap_lock
153 * in get_user_pages() to map the user pages into the kernel address space for
154 * direct IO. Similarly the i_rwsem cannot be taken inside a page fault because
155 * page faults already hold the mmap_lock.
156 *
157 * Hence to serialise fully against both syscall and mmap based IO, we need to
158 * take both the i_rwsem and the i_mmap_lock. These locks should *only* be both
159 * taken in places where we need to invalidate the page cache in a race
160 * free manner (e.g. truncate, hole punch and other extent manipulation
161 * functions).
162 */
163void
164xfs_ilock(
165 xfs_inode_t *ip,
166 uint lock_flags)
167{
168 trace_xfs_ilock(ip, lock_flags, _RET_IP_);
169
170 /*
171 * You can't set both SHARED and EXCL for the same lock,
172 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
173 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
174 */
175 ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
176 (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
177 ASSERT((lock_flags & (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)) !=
178 (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL));
179 ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
180 (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
181 ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0);
182
183 if (lock_flags & XFS_IOLOCK_EXCL) {
184 down_write_nested(&VFS_I(ip)->i_rwsem,
185 XFS_IOLOCK_DEP(lock_flags));
186 } else if (lock_flags & XFS_IOLOCK_SHARED) {
187 down_read_nested(&VFS_I(ip)->i_rwsem,
188 XFS_IOLOCK_DEP(lock_flags));
189 }
190
191 if (lock_flags & XFS_MMAPLOCK_EXCL)
192 mrupdate_nested(&ip->i_mmaplock, XFS_MMAPLOCK_DEP(lock_flags));
193 else if (lock_flags & XFS_MMAPLOCK_SHARED)
194 mraccess_nested(&ip->i_mmaplock, XFS_MMAPLOCK_DEP(lock_flags));
195
196 if (lock_flags & XFS_ILOCK_EXCL)
197 mrupdate_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
198 else if (lock_flags & XFS_ILOCK_SHARED)
199 mraccess_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
200}
201
202/*
203 * This is just like xfs_ilock(), except that the caller
204 * is guaranteed not to sleep. It returns 1 if it gets
205 * the requested locks and 0 otherwise. If the IO lock is
206 * obtained but the inode lock cannot be, then the IO lock
207 * is dropped before returning.
208 *
209 * ip -- the inode being locked
210 * lock_flags -- this parameter indicates the inode's locks to be
211 * to be locked. See the comment for xfs_ilock() for a list
212 * of valid values.
213 */
214int
215xfs_ilock_nowait(
216 xfs_inode_t *ip,
217 uint lock_flags)
218{
219 trace_xfs_ilock_nowait(ip, lock_flags, _RET_IP_);
220
221 /*
222 * You can't set both SHARED and EXCL for the same lock,
223 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
224 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
225 */
226 ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
227 (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
228 ASSERT((lock_flags & (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)) !=
229 (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL));
230 ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
231 (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
232 ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0);
233
234 if (lock_flags & XFS_IOLOCK_EXCL) {
235 if (!down_write_trylock(&VFS_I(ip)->i_rwsem))
236 goto out;
237 } else if (lock_flags & XFS_IOLOCK_SHARED) {
238 if (!down_read_trylock(&VFS_I(ip)->i_rwsem))
239 goto out;
240 }
241
242 if (lock_flags & XFS_MMAPLOCK_EXCL) {
243 if (!mrtryupdate(&ip->i_mmaplock))
244 goto out_undo_iolock;
245 } else if (lock_flags & XFS_MMAPLOCK_SHARED) {
246 if (!mrtryaccess(&ip->i_mmaplock))
247 goto out_undo_iolock;
248 }
249
250 if (lock_flags & XFS_ILOCK_EXCL) {
251 if (!mrtryupdate(&ip->i_lock))
252 goto out_undo_mmaplock;
253 } else if (lock_flags & XFS_ILOCK_SHARED) {
254 if (!mrtryaccess(&ip->i_lock))
255 goto out_undo_mmaplock;
256 }
257 return 1;
258
259out_undo_mmaplock:
260 if (lock_flags & XFS_MMAPLOCK_EXCL)
261 mrunlock_excl(&ip->i_mmaplock);
262 else if (lock_flags & XFS_MMAPLOCK_SHARED)
263 mrunlock_shared(&ip->i_mmaplock);
264out_undo_iolock:
265 if (lock_flags & XFS_IOLOCK_EXCL)
266 up_write(&VFS_I(ip)->i_rwsem);
267 else if (lock_flags & XFS_IOLOCK_SHARED)
268 up_read(&VFS_I(ip)->i_rwsem);
269out:
270 return 0;
271}
272
273/*
274 * xfs_iunlock() is used to drop the inode locks acquired with
275 * xfs_ilock() and xfs_ilock_nowait(). The caller must pass
276 * in the flags given to xfs_ilock() or xfs_ilock_nowait() so
277 * that we know which locks to drop.
278 *
279 * ip -- the inode being unlocked
280 * lock_flags -- this parameter indicates the inode's locks to be
281 * to be unlocked. See the comment for xfs_ilock() for a list
282 * of valid values for this parameter.
283 *
284 */
285void
286xfs_iunlock(
287 xfs_inode_t *ip,
288 uint lock_flags)
289{
290 /*
291 * You can't set both SHARED and EXCL for the same lock,
292 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
293 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
294 */
295 ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
296 (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
297 ASSERT((lock_flags & (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)) !=
298 (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL));
299 ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
300 (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
301 ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0);
302 ASSERT(lock_flags != 0);
303
304 if (lock_flags & XFS_IOLOCK_EXCL)
305 up_write(&VFS_I(ip)->i_rwsem);
306 else if (lock_flags & XFS_IOLOCK_SHARED)
307 up_read(&VFS_I(ip)->i_rwsem);
308
309 if (lock_flags & XFS_MMAPLOCK_EXCL)
310 mrunlock_excl(&ip->i_mmaplock);
311 else if (lock_flags & XFS_MMAPLOCK_SHARED)
312 mrunlock_shared(&ip->i_mmaplock);
313
314 if (lock_flags & XFS_ILOCK_EXCL)
315 mrunlock_excl(&ip->i_lock);
316 else if (lock_flags & XFS_ILOCK_SHARED)
317 mrunlock_shared(&ip->i_lock);
318
319 trace_xfs_iunlock(ip, lock_flags, _RET_IP_);
320}
321
322/*
323 * give up write locks. the i/o lock cannot be held nested
324 * if it is being demoted.
325 */
326void
327xfs_ilock_demote(
328 xfs_inode_t *ip,
329 uint lock_flags)
330{
331 ASSERT(lock_flags & (XFS_IOLOCK_EXCL|XFS_MMAPLOCK_EXCL|XFS_ILOCK_EXCL));
332 ASSERT((lock_flags &
333 ~(XFS_IOLOCK_EXCL|XFS_MMAPLOCK_EXCL|XFS_ILOCK_EXCL)) == 0);
334
335 if (lock_flags & XFS_ILOCK_EXCL)
336 mrdemote(&ip->i_lock);
337 if (lock_flags & XFS_MMAPLOCK_EXCL)
338 mrdemote(&ip->i_mmaplock);
339 if (lock_flags & XFS_IOLOCK_EXCL)
340 downgrade_write(&VFS_I(ip)->i_rwsem);
341
342 trace_xfs_ilock_demote(ip, lock_flags, _RET_IP_);
343}
344
345#if defined(DEBUG) || defined(XFS_WARN)
346int
347xfs_isilocked(
348 xfs_inode_t *ip,
349 uint lock_flags)
350{
351 if (lock_flags & (XFS_ILOCK_EXCL|XFS_ILOCK_SHARED)) {
352 if (!(lock_flags & XFS_ILOCK_SHARED))
353 return !!ip->i_lock.mr_writer;
354 return rwsem_is_locked(&ip->i_lock.mr_lock);
355 }
356
357 if (lock_flags & (XFS_MMAPLOCK_EXCL|XFS_MMAPLOCK_SHARED)) {
358 if (!(lock_flags & XFS_MMAPLOCK_SHARED))
359 return !!ip->i_mmaplock.mr_writer;
360 return rwsem_is_locked(&ip->i_mmaplock.mr_lock);
361 }
362
363 if (lock_flags & (XFS_IOLOCK_EXCL|XFS_IOLOCK_SHARED)) {
364 if (!(lock_flags & XFS_IOLOCK_SHARED))
365 return !debug_locks ||
366 lockdep_is_held_type(&VFS_I(ip)->i_rwsem, 0);
367 return rwsem_is_locked(&VFS_I(ip)->i_rwsem);
368 }
369
370 ASSERT(0);
371 return 0;
372}
373#endif
374
375/*
376 * xfs_lockdep_subclass_ok() is only used in an ASSERT, so is only called when
377 * DEBUG or XFS_WARN is set. And MAX_LOCKDEP_SUBCLASSES is then only defined
378 * when CONFIG_LOCKDEP is set. Hence the complex define below to avoid build
379 * errors and warnings.
380 */
381#if (defined(DEBUG) || defined(XFS_WARN)) && defined(CONFIG_LOCKDEP)
382static bool
383xfs_lockdep_subclass_ok(
384 int subclass)
385{
386 return subclass < MAX_LOCKDEP_SUBCLASSES;
387}
388#else
389#define xfs_lockdep_subclass_ok(subclass) (true)
390#endif
391
392/*
393 * Bump the subclass so xfs_lock_inodes() acquires each lock with a different
394 * value. This can be called for any type of inode lock combination, including
395 * parent locking. Care must be taken to ensure we don't overrun the subclass
396 * storage fields in the class mask we build.
397 */
398static inline int
399xfs_lock_inumorder(int lock_mode, int subclass)
400{
401 int class = 0;
402
403 ASSERT(!(lock_mode & (XFS_ILOCK_PARENT | XFS_ILOCK_RTBITMAP |
404 XFS_ILOCK_RTSUM)));
405 ASSERT(xfs_lockdep_subclass_ok(subclass));
406
407 if (lock_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)) {
408 ASSERT(subclass <= XFS_IOLOCK_MAX_SUBCLASS);
409 class += subclass << XFS_IOLOCK_SHIFT;
410 }
411
412 if (lock_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) {
413 ASSERT(subclass <= XFS_MMAPLOCK_MAX_SUBCLASS);
414 class += subclass << XFS_MMAPLOCK_SHIFT;
415 }
416
417 if (lock_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)) {
418 ASSERT(subclass <= XFS_ILOCK_MAX_SUBCLASS);
419 class += subclass << XFS_ILOCK_SHIFT;
420 }
421
422 return (lock_mode & ~XFS_LOCK_SUBCLASS_MASK) | class;
423}
424
425/*
426 * The following routine will lock n inodes in exclusive mode. We assume the
427 * caller calls us with the inodes in i_ino order.
428 *
429 * We need to detect deadlock where an inode that we lock is in the AIL and we
430 * start waiting for another inode that is locked by a thread in a long running
431 * transaction (such as truncate). This can result in deadlock since the long
432 * running trans might need to wait for the inode we just locked in order to
433 * push the tail and free space in the log.
434 *
435 * xfs_lock_inodes() can only be used to lock one type of lock at a time -
436 * the iolock, the mmaplock or the ilock, but not more than one at a time. If we
437 * lock more than one at a time, lockdep will report false positives saying we
438 * have violated locking orders.
439 */
440static void
441xfs_lock_inodes(
442 struct xfs_inode **ips,
443 int inodes,
444 uint lock_mode)
445{
446 int attempts = 0, i, j, try_lock;
447 struct xfs_log_item *lp;
448
449 /*
450 * Currently supports between 2 and 5 inodes with exclusive locking. We
451 * support an arbitrary depth of locking here, but absolute limits on
452 * inodes depend on the type of locking and the limits placed by
453 * lockdep annotations in xfs_lock_inumorder. These are all checked by
454 * the asserts.
455 */
456 ASSERT(ips && inodes >= 2 && inodes <= 5);
457 ASSERT(lock_mode & (XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL |
458 XFS_ILOCK_EXCL));
459 ASSERT(!(lock_mode & (XFS_IOLOCK_SHARED | XFS_MMAPLOCK_SHARED |
460 XFS_ILOCK_SHARED)));
461 ASSERT(!(lock_mode & XFS_MMAPLOCK_EXCL) ||
462 inodes <= XFS_MMAPLOCK_MAX_SUBCLASS + 1);
463 ASSERT(!(lock_mode & XFS_ILOCK_EXCL) ||
464 inodes <= XFS_ILOCK_MAX_SUBCLASS + 1);
465
466 if (lock_mode & XFS_IOLOCK_EXCL) {
467 ASSERT(!(lock_mode & (XFS_MMAPLOCK_EXCL | XFS_ILOCK_EXCL)));
468 } else if (lock_mode & XFS_MMAPLOCK_EXCL)
469 ASSERT(!(lock_mode & XFS_ILOCK_EXCL));
470
471 try_lock = 0;
472 i = 0;
473again:
474 for (; i < inodes; i++) {
475 ASSERT(ips[i]);
476
477 if (i && (ips[i] == ips[i - 1])) /* Already locked */
478 continue;
479
480 /*
481 * If try_lock is not set yet, make sure all locked inodes are
482 * not in the AIL. If any are, set try_lock to be used later.
483 */
484 if (!try_lock) {
485 for (j = (i - 1); j >= 0 && !try_lock; j--) {
486 lp = &ips[j]->i_itemp->ili_item;
487 if (lp && test_bit(XFS_LI_IN_AIL, &lp->li_flags))
488 try_lock++;
489 }
490 }
491
492 /*
493 * If any of the previous locks we have locked is in the AIL,
494 * we must TRY to get the second and subsequent locks. If
495 * we can't get any, we must release all we have
496 * and try again.
497 */
498 if (!try_lock) {
499 xfs_ilock(ips[i], xfs_lock_inumorder(lock_mode, i));
500 continue;
501 }
502
503 /* try_lock means we have an inode locked that is in the AIL. */
504 ASSERT(i != 0);
505 if (xfs_ilock_nowait(ips[i], xfs_lock_inumorder(lock_mode, i)))
506 continue;
507
508 /*
509 * Unlock all previous guys and try again. xfs_iunlock will try
510 * to push the tail if the inode is in the AIL.
511 */
512 attempts++;
513 for (j = i - 1; j >= 0; j--) {
514 /*
515 * Check to see if we've already unlocked this one. Not
516 * the first one going back, and the inode ptr is the
517 * same.
518 */
519 if (j != (i - 1) && ips[j] == ips[j + 1])
520 continue;
521
522 xfs_iunlock(ips[j], lock_mode);
523 }
524
525 if ((attempts % 5) == 0) {
526 delay(1); /* Don't just spin the CPU */
527 }
528 i = 0;
529 try_lock = 0;
530 goto again;
531 }
532}
533
534/*
535 * xfs_lock_two_inodes() can only be used to lock one type of lock at a time -
536 * the mmaplock or the ilock, but not more than one type at a time. If we lock
537 * more than one at a time, lockdep will report false positives saying we have
538 * violated locking orders. The iolock must be double-locked separately since
539 * we use i_rwsem for that. We now support taking one lock EXCL and the other
540 * SHARED.
541 */
542void
543xfs_lock_two_inodes(
544 struct xfs_inode *ip0,
545 uint ip0_mode,
546 struct xfs_inode *ip1,
547 uint ip1_mode)
548{
549 struct xfs_inode *temp;
550 uint mode_temp;
551 int attempts = 0;
552 struct xfs_log_item *lp;
553
554 ASSERT(hweight32(ip0_mode) == 1);
555 ASSERT(hweight32(ip1_mode) == 1);
556 ASSERT(!(ip0_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)));
557 ASSERT(!(ip1_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)));
558 ASSERT(!(ip0_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) ||
559 !(ip0_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)));
560 ASSERT(!(ip1_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) ||
561 !(ip1_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)));
562 ASSERT(!(ip1_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) ||
563 !(ip0_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)));
564 ASSERT(!(ip0_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) ||
565 !(ip1_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)));
566
567 ASSERT(ip0->i_ino != ip1->i_ino);
568
569 if (ip0->i_ino > ip1->i_ino) {
570 temp = ip0;
571 ip0 = ip1;
572 ip1 = temp;
573 mode_temp = ip0_mode;
574 ip0_mode = ip1_mode;
575 ip1_mode = mode_temp;
576 }
577
578 again:
579 xfs_ilock(ip0, xfs_lock_inumorder(ip0_mode, 0));
580
581 /*
582 * If the first lock we have locked is in the AIL, we must TRY to get
583 * the second lock. If we can't get it, we must release the first one
584 * and try again.
585 */
586 lp = &ip0->i_itemp->ili_item;
587 if (lp && test_bit(XFS_LI_IN_AIL, &lp->li_flags)) {
588 if (!xfs_ilock_nowait(ip1, xfs_lock_inumorder(ip1_mode, 1))) {
589 xfs_iunlock(ip0, ip0_mode);
590 if ((++attempts % 5) == 0)
591 delay(1); /* Don't just spin the CPU */
592 goto again;
593 }
594 } else {
595 xfs_ilock(ip1, xfs_lock_inumorder(ip1_mode, 1));
596 }
597}
598
599uint
600xfs_ip2xflags(
601 struct xfs_inode *ip)
602{
603 uint flags = 0;
604
605 if (ip->i_diflags & XFS_DIFLAG_ANY) {
606 if (ip->i_diflags & XFS_DIFLAG_REALTIME)
607 flags |= FS_XFLAG_REALTIME;
608 if (ip->i_diflags & XFS_DIFLAG_PREALLOC)
609 flags |= FS_XFLAG_PREALLOC;
610 if (ip->i_diflags & XFS_DIFLAG_IMMUTABLE)
611 flags |= FS_XFLAG_IMMUTABLE;
612 if (ip->i_diflags & XFS_DIFLAG_APPEND)
613 flags |= FS_XFLAG_APPEND;
614 if (ip->i_diflags & XFS_DIFLAG_SYNC)
615 flags |= FS_XFLAG_SYNC;
616 if (ip->i_diflags & XFS_DIFLAG_NOATIME)
617 flags |= FS_XFLAG_NOATIME;
618 if (ip->i_diflags & XFS_DIFLAG_NODUMP)
619 flags |= FS_XFLAG_NODUMP;
620 if (ip->i_diflags & XFS_DIFLAG_RTINHERIT)
621 flags |= FS_XFLAG_RTINHERIT;
622 if (ip->i_diflags & XFS_DIFLAG_PROJINHERIT)
623 flags |= FS_XFLAG_PROJINHERIT;
624 if (ip->i_diflags & XFS_DIFLAG_NOSYMLINKS)
625 flags |= FS_XFLAG_NOSYMLINKS;
626 if (ip->i_diflags & XFS_DIFLAG_EXTSIZE)
627 flags |= FS_XFLAG_EXTSIZE;
628 if (ip->i_diflags & XFS_DIFLAG_EXTSZINHERIT)
629 flags |= FS_XFLAG_EXTSZINHERIT;
630 if (ip->i_diflags & XFS_DIFLAG_NODEFRAG)
631 flags |= FS_XFLAG_NODEFRAG;
632 if (ip->i_diflags & XFS_DIFLAG_FILESTREAM)
633 flags |= FS_XFLAG_FILESTREAM;
634 }
635
636 if (ip->i_diflags2 & XFS_DIFLAG2_ANY) {
637 if (ip->i_diflags2 & XFS_DIFLAG2_DAX)
638 flags |= FS_XFLAG_DAX;
639 if (ip->i_diflags2 & XFS_DIFLAG2_COWEXTSIZE)
640 flags |= FS_XFLAG_COWEXTSIZE;
641 }
642
643 if (XFS_IFORK_Q(ip))
644 flags |= FS_XFLAG_HASATTR;
645 return flags;
646}
647
648/*
649 * Lookups up an inode from "name". If ci_name is not NULL, then a CI match
650 * is allowed, otherwise it has to be an exact match. If a CI match is found,
651 * ci_name->name will point to a the actual name (caller must free) or
652 * will be set to NULL if an exact match is found.
653 */
654int
655xfs_lookup(
656 xfs_inode_t *dp,
657 struct xfs_name *name,
658 xfs_inode_t **ipp,
659 struct xfs_name *ci_name)
660{
661 xfs_ino_t inum;
662 int error;
663
664 trace_xfs_lookup(dp, name);
665
666 if (XFS_FORCED_SHUTDOWN(dp->i_mount))
667 return -EIO;
668
669 error = xfs_dir_lookup(NULL, dp, name, &inum, ci_name);
670 if (error)
671 goto out_unlock;
672
673 error = xfs_iget(dp->i_mount, NULL, inum, 0, 0, ipp);
674 if (error)
675 goto out_free_name;
676
677 return 0;
678
679out_free_name:
680 if (ci_name)
681 kmem_free(ci_name->name);
682out_unlock:
683 *ipp = NULL;
684 return error;
685}
686
687/* Propagate di_flags from a parent inode to a child inode. */
688static void
689xfs_inode_inherit_flags(
690 struct xfs_inode *ip,
691 const struct xfs_inode *pip)
692{
693 unsigned int di_flags = 0;
694 xfs_failaddr_t failaddr;
695 umode_t mode = VFS_I(ip)->i_mode;
696
697 if (S_ISDIR(mode)) {
698 if (pip->i_diflags & XFS_DIFLAG_RTINHERIT)
699 di_flags |= XFS_DIFLAG_RTINHERIT;
700 if (pip->i_diflags & XFS_DIFLAG_EXTSZINHERIT) {
701 di_flags |= XFS_DIFLAG_EXTSZINHERIT;
702 ip->i_extsize = pip->i_extsize;
703 }
704 if (pip->i_diflags & XFS_DIFLAG_PROJINHERIT)
705 di_flags |= XFS_DIFLAG_PROJINHERIT;
706 } else if (S_ISREG(mode)) {
707 if ((pip->i_diflags & XFS_DIFLAG_RTINHERIT) &&
708 xfs_sb_version_hasrealtime(&ip->i_mount->m_sb))
709 di_flags |= XFS_DIFLAG_REALTIME;
710 if (pip->i_diflags & XFS_DIFLAG_EXTSZINHERIT) {
711 di_flags |= XFS_DIFLAG_EXTSIZE;
712 ip->i_extsize = pip->i_extsize;
713 }
714 }
715 if ((pip->i_diflags & XFS_DIFLAG_NOATIME) &&
716 xfs_inherit_noatime)
717 di_flags |= XFS_DIFLAG_NOATIME;
718 if ((pip->i_diflags & XFS_DIFLAG_NODUMP) &&
719 xfs_inherit_nodump)
720 di_flags |= XFS_DIFLAG_NODUMP;
721 if ((pip->i_diflags & XFS_DIFLAG_SYNC) &&
722 xfs_inherit_sync)
723 di_flags |= XFS_DIFLAG_SYNC;
724 if ((pip->i_diflags & XFS_DIFLAG_NOSYMLINKS) &&
725 xfs_inherit_nosymlinks)
726 di_flags |= XFS_DIFLAG_NOSYMLINKS;
727 if ((pip->i_diflags & XFS_DIFLAG_NODEFRAG) &&
728 xfs_inherit_nodefrag)
729 di_flags |= XFS_DIFLAG_NODEFRAG;
730 if (pip->i_diflags & XFS_DIFLAG_FILESTREAM)
731 di_flags |= XFS_DIFLAG_FILESTREAM;
732
733 ip->i_diflags |= di_flags;
734
735 /*
736 * Inode verifiers on older kernels only check that the extent size
737 * hint is an integer multiple of the rt extent size on realtime files.
738 * They did not check the hint alignment on a directory with both
739 * rtinherit and extszinherit flags set. If the misaligned hint is
740 * propagated from a directory into a new realtime file, new file
741 * allocations will fail due to math errors in the rt allocator and/or
742 * trip the verifiers. Validate the hint settings in the new file so
743 * that we don't let broken hints propagate.
744 */
745 failaddr = xfs_inode_validate_extsize(ip->i_mount, ip->i_extsize,
746 VFS_I(ip)->i_mode, ip->i_diflags);
747 if (failaddr) {
748 ip->i_diflags &= ~(XFS_DIFLAG_EXTSIZE |
749 XFS_DIFLAG_EXTSZINHERIT);
750 ip->i_extsize = 0;
751 }
752}
753
754/* Propagate di_flags2 from a parent inode to a child inode. */
755static void
756xfs_inode_inherit_flags2(
757 struct xfs_inode *ip,
758 const struct xfs_inode *pip)
759{
760 xfs_failaddr_t failaddr;
761
762 if (pip->i_diflags2 & XFS_DIFLAG2_COWEXTSIZE) {
763 ip->i_diflags2 |= XFS_DIFLAG2_COWEXTSIZE;
764 ip->i_cowextsize = pip->i_cowextsize;
765 }
766 if (pip->i_diflags2 & XFS_DIFLAG2_DAX)
767 ip->i_diflags2 |= XFS_DIFLAG2_DAX;
768
769 /* Don't let invalid cowextsize hints propagate. */
770 failaddr = xfs_inode_validate_cowextsize(ip->i_mount, ip->i_cowextsize,
771 VFS_I(ip)->i_mode, ip->i_diflags, ip->i_diflags2);
772 if (failaddr) {
773 ip->i_diflags2 &= ~XFS_DIFLAG2_COWEXTSIZE;
774 ip->i_cowextsize = 0;
775 }
776}
777
778/*
779 * Initialise a newly allocated inode and return the in-core inode to the
780 * caller locked exclusively.
781 */
782int
783xfs_init_new_inode(
784 struct user_namespace *mnt_userns,
785 struct xfs_trans *tp,
786 struct xfs_inode *pip,
787 xfs_ino_t ino,
788 umode_t mode,
789 xfs_nlink_t nlink,
790 dev_t rdev,
791 prid_t prid,
792 bool init_xattrs,
793 struct xfs_inode **ipp)
794{
795 struct inode *dir = pip ? VFS_I(pip) : NULL;
796 struct xfs_mount *mp = tp->t_mountp;
797 struct xfs_inode *ip;
798 unsigned int flags;
799 int error;
800 struct timespec64 tv;
801 struct inode *inode;
802
803 /*
804 * Protect against obviously corrupt allocation btree records. Later
805 * xfs_iget checks will catch re-allocation of other active in-memory
806 * and on-disk inodes. If we don't catch reallocating the parent inode
807 * here we will deadlock in xfs_iget() so we have to do these checks
808 * first.
809 */
810 if ((pip && ino == pip->i_ino) || !xfs_verify_dir_ino(mp, ino)) {
811 xfs_alert(mp, "Allocated a known in-use inode 0x%llx!", ino);
812 return -EFSCORRUPTED;
813 }
814
815 /*
816 * Get the in-core inode with the lock held exclusively to prevent
817 * others from looking at until we're done.
818 */
819 error = xfs_iget(mp, tp, ino, XFS_IGET_CREATE, XFS_ILOCK_EXCL, &ip);
820 if (error)
821 return error;
822
823 ASSERT(ip != NULL);
824 inode = VFS_I(ip);
825 set_nlink(inode, nlink);
826 inode->i_rdev = rdev;
827 ip->i_projid = prid;
828
829 if (dir && !(dir->i_mode & S_ISGID) &&
830 (mp->m_flags & XFS_MOUNT_GRPID)) {
831 inode_fsuid_set(inode, mnt_userns);
832 inode->i_gid = dir->i_gid;
833 inode->i_mode = mode;
834 } else {
835 inode_init_owner(mnt_userns, inode, dir, mode);
836 }
837
838 /*
839 * If the group ID of the new file does not match the effective group
840 * ID or one of the supplementary group IDs, the S_ISGID bit is cleared
841 * (and only if the irix_sgid_inherit compatibility variable is set).
842 */
843 if (irix_sgid_inherit &&
844 (inode->i_mode & S_ISGID) &&
845 !in_group_p(i_gid_into_mnt(mnt_userns, inode)))
846 inode->i_mode &= ~S_ISGID;
847
848 ip->i_disk_size = 0;
849 ip->i_df.if_nextents = 0;
850 ASSERT(ip->i_nblocks == 0);
851
852 tv = current_time(inode);
853 inode->i_mtime = tv;
854 inode->i_atime = tv;
855 inode->i_ctime = tv;
856
857 ip->i_extsize = 0;
858 ip->i_diflags = 0;
859
860 if (xfs_sb_version_has_v3inode(&mp->m_sb)) {
861 inode_set_iversion(inode, 1);
862 ip->i_cowextsize = 0;
863 ip->i_crtime = tv;
864 }
865
866 flags = XFS_ILOG_CORE;
867 switch (mode & S_IFMT) {
868 case S_IFIFO:
869 case S_IFCHR:
870 case S_IFBLK:
871 case S_IFSOCK:
872 ip->i_df.if_format = XFS_DINODE_FMT_DEV;
873 flags |= XFS_ILOG_DEV;
874 break;
875 case S_IFREG:
876 case S_IFDIR:
877 if (pip && (pip->i_diflags & XFS_DIFLAG_ANY))
878 xfs_inode_inherit_flags(ip, pip);
879 if (pip && (pip->i_diflags2 & XFS_DIFLAG2_ANY))
880 xfs_inode_inherit_flags2(ip, pip);
881 fallthrough;
882 case S_IFLNK:
883 ip->i_df.if_format = XFS_DINODE_FMT_EXTENTS;
884 ip->i_df.if_bytes = 0;
885 ip->i_df.if_u1.if_root = NULL;
886 break;
887 default:
888 ASSERT(0);
889 }
890
891 /*
892 * If we need to create attributes immediately after allocating the
893 * inode, initialise an empty attribute fork right now. We use the
894 * default fork offset for attributes here as we don't know exactly what
895 * size or how many attributes we might be adding. We can do this
896 * safely here because we know the data fork is completely empty and
897 * this saves us from needing to run a separate transaction to set the
898 * fork offset in the immediate future.
899 */
900 if (init_xattrs && xfs_sb_version_hasattr(&mp->m_sb)) {
901 ip->i_forkoff = xfs_default_attroffset(ip) >> 3;
902 ip->i_afp = xfs_ifork_alloc(XFS_DINODE_FMT_EXTENTS, 0);
903 }
904
905 /*
906 * Log the new values stuffed into the inode.
907 */
908 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
909 xfs_trans_log_inode(tp, ip, flags);
910
911 /* now that we have an i_mode we can setup the inode structure */
912 xfs_setup_inode(ip);
913
914 *ipp = ip;
915 return 0;
916}
917
918/*
919 * Decrement the link count on an inode & log the change. If this causes the
920 * link count to go to zero, move the inode to AGI unlinked list so that it can
921 * be freed when the last active reference goes away via xfs_inactive().
922 */
923static int /* error */
924xfs_droplink(
925 xfs_trans_t *tp,
926 xfs_inode_t *ip)
927{
928 xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
929
930 drop_nlink(VFS_I(ip));
931 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
932
933 if (VFS_I(ip)->i_nlink)
934 return 0;
935
936 return xfs_iunlink(tp, ip);
937}
938
939/*
940 * Increment the link count on an inode & log the change.
941 */
942static void
943xfs_bumplink(
944 xfs_trans_t *tp,
945 xfs_inode_t *ip)
946{
947 xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
948
949 inc_nlink(VFS_I(ip));
950 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
951}
952
953int
954xfs_create(
955 struct user_namespace *mnt_userns,
956 xfs_inode_t *dp,
957 struct xfs_name *name,
958 umode_t mode,
959 dev_t rdev,
960 bool init_xattrs,
961 xfs_inode_t **ipp)
962{
963 int is_dir = S_ISDIR(mode);
964 struct xfs_mount *mp = dp->i_mount;
965 struct xfs_inode *ip = NULL;
966 struct xfs_trans *tp = NULL;
967 int error;
968 bool unlock_dp_on_error = false;
969 prid_t prid;
970 struct xfs_dquot *udqp = NULL;
971 struct xfs_dquot *gdqp = NULL;
972 struct xfs_dquot *pdqp = NULL;
973 struct xfs_trans_res *tres;
974 uint resblks;
975 xfs_ino_t ino;
976
977 trace_xfs_create(dp, name);
978
979 if (XFS_FORCED_SHUTDOWN(mp))
980 return -EIO;
981
982 prid = xfs_get_initial_prid(dp);
983
984 /*
985 * Make sure that we have allocated dquot(s) on disk.
986 */
987 error = xfs_qm_vop_dqalloc(dp, mapped_fsuid(mnt_userns),
988 mapped_fsgid(mnt_userns), prid,
989 XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
990 &udqp, &gdqp, &pdqp);
991 if (error)
992 return error;
993
994 if (is_dir) {
995 resblks = XFS_MKDIR_SPACE_RES(mp, name->len);
996 tres = &M_RES(mp)->tr_mkdir;
997 } else {
998 resblks = XFS_CREATE_SPACE_RES(mp, name->len);
999 tres = &M_RES(mp)->tr_create;
1000 }
1001
1002 /*
1003 * Initially assume that the file does not exist and
1004 * reserve the resources for that case. If that is not
1005 * the case we'll drop the one we have and get a more
1006 * appropriate transaction later.
1007 */
1008 error = xfs_trans_alloc_icreate(mp, tres, udqp, gdqp, pdqp, resblks,
1009 &tp);
1010 if (error == -ENOSPC) {
1011 /* flush outstanding delalloc blocks and retry */
1012 xfs_flush_inodes(mp);
1013 error = xfs_trans_alloc_icreate(mp, tres, udqp, gdqp, pdqp,
1014 resblks, &tp);
1015 }
1016 if (error)
1017 goto out_release_dquots;
1018
1019 xfs_ilock(dp, XFS_ILOCK_EXCL | XFS_ILOCK_PARENT);
1020 unlock_dp_on_error = true;
1021
1022 error = xfs_iext_count_may_overflow(dp, XFS_DATA_FORK,
1023 XFS_IEXT_DIR_MANIP_CNT(mp));
1024 if (error)
1025 goto out_trans_cancel;
1026
1027 /*
1028 * A newly created regular or special file just has one directory
1029 * entry pointing to them, but a directory also the "." entry
1030 * pointing to itself.
1031 */
1032 error = xfs_dialloc(&tp, dp->i_ino, mode, &ino);
1033 if (!error)
1034 error = xfs_init_new_inode(mnt_userns, tp, dp, ino, mode,
1035 is_dir ? 2 : 1, rdev, prid, init_xattrs, &ip);
1036 if (error)
1037 goto out_trans_cancel;
1038
1039 /*
1040 * Now we join the directory inode to the transaction. We do not do it
1041 * earlier because xfs_dialloc might commit the previous transaction
1042 * (and release all the locks). An error from here on will result in
1043 * the transaction cancel unlocking dp so don't do it explicitly in the
1044 * error path.
1045 */
1046 xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
1047 unlock_dp_on_error = false;
1048
1049 error = xfs_dir_createname(tp, dp, name, ip->i_ino,
1050 resblks - XFS_IALLOC_SPACE_RES(mp));
1051 if (error) {
1052 ASSERT(error != -ENOSPC);
1053 goto out_trans_cancel;
1054 }
1055 xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1056 xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
1057
1058 if (is_dir) {
1059 error = xfs_dir_init(tp, ip, dp);
1060 if (error)
1061 goto out_trans_cancel;
1062
1063 xfs_bumplink(tp, dp);
1064 }
1065
1066 /*
1067 * If this is a synchronous mount, make sure that the
1068 * create transaction goes to disk before returning to
1069 * the user.
1070 */
1071 if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
1072 xfs_trans_set_sync(tp);
1073
1074 /*
1075 * Attach the dquot(s) to the inodes and modify them incore.
1076 * These ids of the inode couldn't have changed since the new
1077 * inode has been locked ever since it was created.
1078 */
1079 xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp, pdqp);
1080
1081 error = xfs_trans_commit(tp);
1082 if (error)
1083 goto out_release_inode;
1084
1085 xfs_qm_dqrele(udqp);
1086 xfs_qm_dqrele(gdqp);
1087 xfs_qm_dqrele(pdqp);
1088
1089 *ipp = ip;
1090 return 0;
1091
1092 out_trans_cancel:
1093 xfs_trans_cancel(tp);
1094 out_release_inode:
1095 /*
1096 * Wait until after the current transaction is aborted to finish the
1097 * setup of the inode and release the inode. This prevents recursive
1098 * transactions and deadlocks from xfs_inactive.
1099 */
1100 if (ip) {
1101 xfs_finish_inode_setup(ip);
1102 xfs_irele(ip);
1103 }
1104 out_release_dquots:
1105 xfs_qm_dqrele(udqp);
1106 xfs_qm_dqrele(gdqp);
1107 xfs_qm_dqrele(pdqp);
1108
1109 if (unlock_dp_on_error)
1110 xfs_iunlock(dp, XFS_ILOCK_EXCL);
1111 return error;
1112}
1113
1114int
1115xfs_create_tmpfile(
1116 struct user_namespace *mnt_userns,
1117 struct xfs_inode *dp,
1118 umode_t mode,
1119 struct xfs_inode **ipp)
1120{
1121 struct xfs_mount *mp = dp->i_mount;
1122 struct xfs_inode *ip = NULL;
1123 struct xfs_trans *tp = NULL;
1124 int error;
1125 prid_t prid;
1126 struct xfs_dquot *udqp = NULL;
1127 struct xfs_dquot *gdqp = NULL;
1128 struct xfs_dquot *pdqp = NULL;
1129 struct xfs_trans_res *tres;
1130 uint resblks;
1131 xfs_ino_t ino;
1132
1133 if (XFS_FORCED_SHUTDOWN(mp))
1134 return -EIO;
1135
1136 prid = xfs_get_initial_prid(dp);
1137
1138 /*
1139 * Make sure that we have allocated dquot(s) on disk.
1140 */
1141 error = xfs_qm_vop_dqalloc(dp, mapped_fsuid(mnt_userns),
1142 mapped_fsgid(mnt_userns), prid,
1143 XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
1144 &udqp, &gdqp, &pdqp);
1145 if (error)
1146 return error;
1147
1148 resblks = XFS_IALLOC_SPACE_RES(mp);
1149 tres = &M_RES(mp)->tr_create_tmpfile;
1150
1151 error = xfs_trans_alloc_icreate(mp, tres, udqp, gdqp, pdqp, resblks,
1152 &tp);
1153 if (error)
1154 goto out_release_dquots;
1155
1156 error = xfs_dialloc(&tp, dp->i_ino, mode, &ino);
1157 if (!error)
1158 error = xfs_init_new_inode(mnt_userns, tp, dp, ino, mode,
1159 0, 0, prid, false, &ip);
1160 if (error)
1161 goto out_trans_cancel;
1162
1163 if (mp->m_flags & XFS_MOUNT_WSYNC)
1164 xfs_trans_set_sync(tp);
1165
1166 /*
1167 * Attach the dquot(s) to the inodes and modify them incore.
1168 * These ids of the inode couldn't have changed since the new
1169 * inode has been locked ever since it was created.
1170 */
1171 xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp, pdqp);
1172
1173 error = xfs_iunlink(tp, ip);
1174 if (error)
1175 goto out_trans_cancel;
1176
1177 error = xfs_trans_commit(tp);
1178 if (error)
1179 goto out_release_inode;
1180
1181 xfs_qm_dqrele(udqp);
1182 xfs_qm_dqrele(gdqp);
1183 xfs_qm_dqrele(pdqp);
1184
1185 *ipp = ip;
1186 return 0;
1187
1188 out_trans_cancel:
1189 xfs_trans_cancel(tp);
1190 out_release_inode:
1191 /*
1192 * Wait until after the current transaction is aborted to finish the
1193 * setup of the inode and release the inode. This prevents recursive
1194 * transactions and deadlocks from xfs_inactive.
1195 */
1196 if (ip) {
1197 xfs_finish_inode_setup(ip);
1198 xfs_irele(ip);
1199 }
1200 out_release_dquots:
1201 xfs_qm_dqrele(udqp);
1202 xfs_qm_dqrele(gdqp);
1203 xfs_qm_dqrele(pdqp);
1204
1205 return error;
1206}
1207
1208int
1209xfs_link(
1210 xfs_inode_t *tdp,
1211 xfs_inode_t *sip,
1212 struct xfs_name *target_name)
1213{
1214 xfs_mount_t *mp = tdp->i_mount;
1215 xfs_trans_t *tp;
1216 int error;
1217 int resblks;
1218
1219 trace_xfs_link(tdp, target_name);
1220
1221 ASSERT(!S_ISDIR(VFS_I(sip)->i_mode));
1222
1223 if (XFS_FORCED_SHUTDOWN(mp))
1224 return -EIO;
1225
1226 error = xfs_qm_dqattach(sip);
1227 if (error)
1228 goto std_return;
1229
1230 error = xfs_qm_dqattach(tdp);
1231 if (error)
1232 goto std_return;
1233
1234 resblks = XFS_LINK_SPACE_RES(mp, target_name->len);
1235 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_link, resblks, 0, 0, &tp);
1236 if (error == -ENOSPC) {
1237 resblks = 0;
1238 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_link, 0, 0, 0, &tp);
1239 }
1240 if (error)
1241 goto std_return;
1242
1243 xfs_lock_two_inodes(sip, XFS_ILOCK_EXCL, tdp, XFS_ILOCK_EXCL);
1244
1245 xfs_trans_ijoin(tp, sip, XFS_ILOCK_EXCL);
1246 xfs_trans_ijoin(tp, tdp, XFS_ILOCK_EXCL);
1247
1248 error = xfs_iext_count_may_overflow(tdp, XFS_DATA_FORK,
1249 XFS_IEXT_DIR_MANIP_CNT(mp));
1250 if (error)
1251 goto error_return;
1252
1253 /*
1254 * If we are using project inheritance, we only allow hard link
1255 * creation in our tree when the project IDs are the same; else
1256 * the tree quota mechanism could be circumvented.
1257 */
1258 if (unlikely((tdp->i_diflags & XFS_DIFLAG_PROJINHERIT) &&
1259 tdp->i_projid != sip->i_projid)) {
1260 error = -EXDEV;
1261 goto error_return;
1262 }
1263
1264 if (!resblks) {
1265 error = xfs_dir_canenter(tp, tdp, target_name);
1266 if (error)
1267 goto error_return;
1268 }
1269
1270 /*
1271 * Handle initial link state of O_TMPFILE inode
1272 */
1273 if (VFS_I(sip)->i_nlink == 0) {
1274 struct xfs_perag *pag;
1275
1276 pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, sip->i_ino));
1277 error = xfs_iunlink_remove(tp, pag, sip);
1278 xfs_perag_put(pag);
1279 if (error)
1280 goto error_return;
1281 }
1282
1283 error = xfs_dir_createname(tp, tdp, target_name, sip->i_ino,
1284 resblks);
1285 if (error)
1286 goto error_return;
1287 xfs_trans_ichgtime(tp, tdp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1288 xfs_trans_log_inode(tp, tdp, XFS_ILOG_CORE);
1289
1290 xfs_bumplink(tp, sip);
1291
1292 /*
1293 * If this is a synchronous mount, make sure that the
1294 * link transaction goes to disk before returning to
1295 * the user.
1296 */
1297 if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
1298 xfs_trans_set_sync(tp);
1299
1300 return xfs_trans_commit(tp);
1301
1302 error_return:
1303 xfs_trans_cancel(tp);
1304 std_return:
1305 return error;
1306}
1307
1308/* Clear the reflink flag and the cowblocks tag if possible. */
1309static void
1310xfs_itruncate_clear_reflink_flags(
1311 struct xfs_inode *ip)
1312{
1313 struct xfs_ifork *dfork;
1314 struct xfs_ifork *cfork;
1315
1316 if (!xfs_is_reflink_inode(ip))
1317 return;
1318 dfork = XFS_IFORK_PTR(ip, XFS_DATA_FORK);
1319 cfork = XFS_IFORK_PTR(ip, XFS_COW_FORK);
1320 if (dfork->if_bytes == 0 && cfork->if_bytes == 0)
1321 ip->i_diflags2 &= ~XFS_DIFLAG2_REFLINK;
1322 if (cfork->if_bytes == 0)
1323 xfs_inode_clear_cowblocks_tag(ip);
1324}
1325
1326/*
1327 * Free up the underlying blocks past new_size. The new size must be smaller
1328 * than the current size. This routine can be used both for the attribute and
1329 * data fork, and does not modify the inode size, which is left to the caller.
1330 *
1331 * The transaction passed to this routine must have made a permanent log
1332 * reservation of at least XFS_ITRUNCATE_LOG_RES. This routine may commit the
1333 * given transaction and start new ones, so make sure everything involved in
1334 * the transaction is tidy before calling here. Some transaction will be
1335 * returned to the caller to be committed. The incoming transaction must
1336 * already include the inode, and both inode locks must be held exclusively.
1337 * The inode must also be "held" within the transaction. On return the inode
1338 * will be "held" within the returned transaction. This routine does NOT
1339 * require any disk space to be reserved for it within the transaction.
1340 *
1341 * If we get an error, we must return with the inode locked and linked into the
1342 * current transaction. This keeps things simple for the higher level code,
1343 * because it always knows that the inode is locked and held in the transaction
1344 * that returns to it whether errors occur or not. We don't mark the inode
1345 * dirty on error so that transactions can be easily aborted if possible.
1346 */
1347int
1348xfs_itruncate_extents_flags(
1349 struct xfs_trans **tpp,
1350 struct xfs_inode *ip,
1351 int whichfork,
1352 xfs_fsize_t new_size,
1353 int flags)
1354{
1355 struct xfs_mount *mp = ip->i_mount;
1356 struct xfs_trans *tp = *tpp;
1357 xfs_fileoff_t first_unmap_block;
1358 xfs_filblks_t unmap_len;
1359 int error = 0;
1360
1361 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
1362 ASSERT(!atomic_read(&VFS_I(ip)->i_count) ||
1363 xfs_isilocked(ip, XFS_IOLOCK_EXCL));
1364 ASSERT(new_size <= XFS_ISIZE(ip));
1365 ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
1366 ASSERT(ip->i_itemp != NULL);
1367 ASSERT(ip->i_itemp->ili_lock_flags == 0);
1368 ASSERT(!XFS_NOT_DQATTACHED(mp, ip));
1369
1370 trace_xfs_itruncate_extents_start(ip, new_size);
1371
1372 flags |= xfs_bmapi_aflag(whichfork);
1373
1374 /*
1375 * Since it is possible for space to become allocated beyond
1376 * the end of the file (in a crash where the space is allocated
1377 * but the inode size is not yet updated), simply remove any
1378 * blocks which show up between the new EOF and the maximum
1379 * possible file size.
1380 *
1381 * We have to free all the blocks to the bmbt maximum offset, even if
1382 * the page cache can't scale that far.
1383 */
1384 first_unmap_block = XFS_B_TO_FSB(mp, (xfs_ufsize_t)new_size);
1385 if (!xfs_verify_fileoff(mp, first_unmap_block)) {
1386 WARN_ON_ONCE(first_unmap_block > XFS_MAX_FILEOFF);
1387 return 0;
1388 }
1389
1390 unmap_len = XFS_MAX_FILEOFF - first_unmap_block + 1;
1391 while (unmap_len > 0) {
1392 ASSERT(tp->t_firstblock == NULLFSBLOCK);
1393 error = __xfs_bunmapi(tp, ip, first_unmap_block, &unmap_len,
1394 flags, XFS_ITRUNC_MAX_EXTENTS);
1395 if (error)
1396 goto out;
1397
1398 /* free the just unmapped extents */
1399 error = xfs_defer_finish(&tp);
1400 if (error)
1401 goto out;
1402 }
1403
1404 if (whichfork == XFS_DATA_FORK) {
1405 /* Remove all pending CoW reservations. */
1406 error = xfs_reflink_cancel_cow_blocks(ip, &tp,
1407 first_unmap_block, XFS_MAX_FILEOFF, true);
1408 if (error)
1409 goto out;
1410
1411 xfs_itruncate_clear_reflink_flags(ip);
1412 }
1413
1414 /*
1415 * Always re-log the inode so that our permanent transaction can keep
1416 * on rolling it forward in the log.
1417 */
1418 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1419
1420 trace_xfs_itruncate_extents_end(ip, new_size);
1421
1422out:
1423 *tpp = tp;
1424 return error;
1425}
1426
1427int
1428xfs_release(
1429 xfs_inode_t *ip)
1430{
1431 xfs_mount_t *mp = ip->i_mount;
1432 int error = 0;
1433
1434 if (!S_ISREG(VFS_I(ip)->i_mode) || (VFS_I(ip)->i_mode == 0))
1435 return 0;
1436
1437 /* If this is a read-only mount, don't do this (would generate I/O) */
1438 if (mp->m_flags & XFS_MOUNT_RDONLY)
1439 return 0;
1440
1441 if (!XFS_FORCED_SHUTDOWN(mp)) {
1442 int truncated;
1443
1444 /*
1445 * If we previously truncated this file and removed old data
1446 * in the process, we want to initiate "early" writeout on
1447 * the last close. This is an attempt to combat the notorious
1448 * NULL files problem which is particularly noticeable from a
1449 * truncate down, buffered (re-)write (delalloc), followed by
1450 * a crash. What we are effectively doing here is
1451 * significantly reducing the time window where we'd otherwise
1452 * be exposed to that problem.
1453 */
1454 truncated = xfs_iflags_test_and_clear(ip, XFS_ITRUNCATED);
1455 if (truncated) {
1456 xfs_iflags_clear(ip, XFS_IDIRTY_RELEASE);
1457 if (ip->i_delayed_blks > 0) {
1458 error = filemap_flush(VFS_I(ip)->i_mapping);
1459 if (error)
1460 return error;
1461 }
1462 }
1463 }
1464
1465 if (VFS_I(ip)->i_nlink == 0)
1466 return 0;
1467
1468 /*
1469 * If we can't get the iolock just skip truncating the blocks past EOF
1470 * because we could deadlock with the mmap_lock otherwise. We'll get
1471 * another chance to drop them once the last reference to the inode is
1472 * dropped, so we'll never leak blocks permanently.
1473 */
1474 if (!xfs_ilock_nowait(ip, XFS_IOLOCK_EXCL))
1475 return 0;
1476
1477 if (xfs_can_free_eofblocks(ip, false)) {
1478 /*
1479 * Check if the inode is being opened, written and closed
1480 * frequently and we have delayed allocation blocks outstanding
1481 * (e.g. streaming writes from the NFS server), truncating the
1482 * blocks past EOF will cause fragmentation to occur.
1483 *
1484 * In this case don't do the truncation, but we have to be
1485 * careful how we detect this case. Blocks beyond EOF show up as
1486 * i_delayed_blks even when the inode is clean, so we need to
1487 * truncate them away first before checking for a dirty release.
1488 * Hence on the first dirty close we will still remove the
1489 * speculative allocation, but after that we will leave it in
1490 * place.
1491 */
1492 if (xfs_iflags_test(ip, XFS_IDIRTY_RELEASE))
1493 goto out_unlock;
1494
1495 error = xfs_free_eofblocks(ip);
1496 if (error)
1497 goto out_unlock;
1498
1499 /* delalloc blocks after truncation means it really is dirty */
1500 if (ip->i_delayed_blks)
1501 xfs_iflags_set(ip, XFS_IDIRTY_RELEASE);
1502 }
1503
1504out_unlock:
1505 xfs_iunlock(ip, XFS_IOLOCK_EXCL);
1506 return error;
1507}
1508
1509/*
1510 * xfs_inactive_truncate
1511 *
1512 * Called to perform a truncate when an inode becomes unlinked.
1513 */
1514STATIC int
1515xfs_inactive_truncate(
1516 struct xfs_inode *ip)
1517{
1518 struct xfs_mount *mp = ip->i_mount;
1519 struct xfs_trans *tp;
1520 int error;
1521
1522 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, 0, 0, 0, &tp);
1523 if (error) {
1524 ASSERT(XFS_FORCED_SHUTDOWN(mp));
1525 return error;
1526 }
1527 xfs_ilock(ip, XFS_ILOCK_EXCL);
1528 xfs_trans_ijoin(tp, ip, 0);
1529
1530 /*
1531 * Log the inode size first to prevent stale data exposure in the event
1532 * of a system crash before the truncate completes. See the related
1533 * comment in xfs_vn_setattr_size() for details.
1534 */
1535 ip->i_disk_size = 0;
1536 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1537
1538 error = xfs_itruncate_extents(&tp, ip, XFS_DATA_FORK, 0);
1539 if (error)
1540 goto error_trans_cancel;
1541
1542 ASSERT(ip->i_df.if_nextents == 0);
1543
1544 error = xfs_trans_commit(tp);
1545 if (error)
1546 goto error_unlock;
1547
1548 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1549 return 0;
1550
1551error_trans_cancel:
1552 xfs_trans_cancel(tp);
1553error_unlock:
1554 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1555 return error;
1556}
1557
1558/*
1559 * xfs_inactive_ifree()
1560 *
1561 * Perform the inode free when an inode is unlinked.
1562 */
1563STATIC int
1564xfs_inactive_ifree(
1565 struct xfs_inode *ip)
1566{
1567 struct xfs_mount *mp = ip->i_mount;
1568 struct xfs_trans *tp;
1569 int error;
1570
1571 /*
1572 * We try to use a per-AG reservation for any block needed by the finobt
1573 * tree, but as the finobt feature predates the per-AG reservation
1574 * support a degraded file system might not have enough space for the
1575 * reservation at mount time. In that case try to dip into the reserved
1576 * pool and pray.
1577 *
1578 * Send a warning if the reservation does happen to fail, as the inode
1579 * now remains allocated and sits on the unlinked list until the fs is
1580 * repaired.
1581 */
1582 if (unlikely(mp->m_finobt_nores)) {
1583 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ifree,
1584 XFS_IFREE_SPACE_RES(mp), 0, XFS_TRANS_RESERVE,
1585 &tp);
1586 } else {
1587 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ifree, 0, 0, 0, &tp);
1588 }
1589 if (error) {
1590 if (error == -ENOSPC) {
1591 xfs_warn_ratelimited(mp,
1592 "Failed to remove inode(s) from unlinked list. "
1593 "Please free space, unmount and run xfs_repair.");
1594 } else {
1595 ASSERT(XFS_FORCED_SHUTDOWN(mp));
1596 }
1597 return error;
1598 }
1599
1600 /*
1601 * We do not hold the inode locked across the entire rolling transaction
1602 * here. We only need to hold it for the first transaction that
1603 * xfs_ifree() builds, which may mark the inode XFS_ISTALE if the
1604 * underlying cluster buffer is freed. Relogging an XFS_ISTALE inode
1605 * here breaks the relationship between cluster buffer invalidation and
1606 * stale inode invalidation on cluster buffer item journal commit
1607 * completion, and can result in leaving dirty stale inodes hanging
1608 * around in memory.
1609 *
1610 * We have no need for serialising this inode operation against other
1611 * operations - we freed the inode and hence reallocation is required
1612 * and that will serialise on reallocating the space the deferops need
1613 * to free. Hence we can unlock the inode on the first commit of
1614 * the transaction rather than roll it right through the deferops. This
1615 * avoids relogging the XFS_ISTALE inode.
1616 *
1617 * We check that xfs_ifree() hasn't grown an internal transaction roll
1618 * by asserting that the inode is still locked when it returns.
1619 */
1620 xfs_ilock(ip, XFS_ILOCK_EXCL);
1621 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
1622
1623 error = xfs_ifree(tp, ip);
1624 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
1625 if (error) {
1626 /*
1627 * If we fail to free the inode, shut down. The cancel
1628 * might do that, we need to make sure. Otherwise the
1629 * inode might be lost for a long time or forever.
1630 */
1631 if (!XFS_FORCED_SHUTDOWN(mp)) {
1632 xfs_notice(mp, "%s: xfs_ifree returned error %d",
1633 __func__, error);
1634 xfs_force_shutdown(mp, SHUTDOWN_META_IO_ERROR);
1635 }
1636 xfs_trans_cancel(tp);
1637 return error;
1638 }
1639
1640 /*
1641 * Credit the quota account(s). The inode is gone.
1642 */
1643 xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_ICOUNT, -1);
1644
1645 /*
1646 * Just ignore errors at this point. There is nothing we can do except
1647 * to try to keep going. Make sure it's not a silent error.
1648 */
1649 error = xfs_trans_commit(tp);
1650 if (error)
1651 xfs_notice(mp, "%s: xfs_trans_commit returned error %d",
1652 __func__, error);
1653
1654 return 0;
1655}
1656
1657/*
1658 * xfs_inactive
1659 *
1660 * This is called when the vnode reference count for the vnode
1661 * goes to zero. If the file has been unlinked, then it must
1662 * now be truncated. Also, we clear all of the read-ahead state
1663 * kept for the inode here since the file is now closed.
1664 */
1665void
1666xfs_inactive(
1667 xfs_inode_t *ip)
1668{
1669 struct xfs_mount *mp;
1670 int error;
1671 int truncate = 0;
1672
1673 /*
1674 * If the inode is already free, then there can be nothing
1675 * to clean up here.
1676 */
1677 if (VFS_I(ip)->i_mode == 0) {
1678 ASSERT(ip->i_df.if_broot_bytes == 0);
1679 goto out;
1680 }
1681
1682 mp = ip->i_mount;
1683 ASSERT(!xfs_iflags_test(ip, XFS_IRECOVERY));
1684
1685 /* If this is a read-only mount, don't do this (would generate I/O) */
1686 if (mp->m_flags & XFS_MOUNT_RDONLY)
1687 goto out;
1688
1689 /* Metadata inodes require explicit resource cleanup. */
1690 if (xfs_is_metadata_inode(ip))
1691 goto out;
1692
1693 /* Try to clean out the cow blocks if there are any. */
1694 if (xfs_inode_has_cow_data(ip))
1695 xfs_reflink_cancel_cow_range(ip, 0, NULLFILEOFF, true);
1696
1697 if (VFS_I(ip)->i_nlink != 0) {
1698 /*
1699 * force is true because we are evicting an inode from the
1700 * cache. Post-eof blocks must be freed, lest we end up with
1701 * broken free space accounting.
1702 *
1703 * Note: don't bother with iolock here since lockdep complains
1704 * about acquiring it in reclaim context. We have the only
1705 * reference to the inode at this point anyways.
1706 */
1707 if (xfs_can_free_eofblocks(ip, true))
1708 xfs_free_eofblocks(ip);
1709
1710 goto out;
1711 }
1712
1713 if (S_ISREG(VFS_I(ip)->i_mode) &&
1714 (ip->i_disk_size != 0 || XFS_ISIZE(ip) != 0 ||
1715 ip->i_df.if_nextents > 0 || ip->i_delayed_blks > 0))
1716 truncate = 1;
1717
1718 error = xfs_qm_dqattach(ip);
1719 if (error)
1720 goto out;
1721
1722 if (S_ISLNK(VFS_I(ip)->i_mode))
1723 error = xfs_inactive_symlink(ip);
1724 else if (truncate)
1725 error = xfs_inactive_truncate(ip);
1726 if (error)
1727 goto out;
1728
1729 /*
1730 * If there are attributes associated with the file then blow them away
1731 * now. The code calls a routine that recursively deconstructs the
1732 * attribute fork. If also blows away the in-core attribute fork.
1733 */
1734 if (XFS_IFORK_Q(ip)) {
1735 error = xfs_attr_inactive(ip);
1736 if (error)
1737 goto out;
1738 }
1739
1740 ASSERT(!ip->i_afp);
1741 ASSERT(ip->i_forkoff == 0);
1742
1743 /*
1744 * Free the inode.
1745 */
1746 xfs_inactive_ifree(ip);
1747
1748out:
1749 /*
1750 * We're done making metadata updates for this inode, so we can release
1751 * the attached dquots.
1752 */
1753 xfs_qm_dqdetach(ip);
1754}
1755
1756/*
1757 * In-Core Unlinked List Lookups
1758 * =============================
1759 *
1760 * Every inode is supposed to be reachable from some other piece of metadata
1761 * with the exception of the root directory. Inodes with a connection to a
1762 * file descriptor but not linked from anywhere in the on-disk directory tree
1763 * are collectively known as unlinked inodes, though the filesystem itself
1764 * maintains links to these inodes so that on-disk metadata are consistent.
1765 *
1766 * XFS implements a per-AG on-disk hash table of unlinked inodes. The AGI
1767 * header contains a number of buckets that point to an inode, and each inode
1768 * record has a pointer to the next inode in the hash chain. This
1769 * singly-linked list causes scaling problems in the iunlink remove function
1770 * because we must walk that list to find the inode that points to the inode
1771 * being removed from the unlinked hash bucket list.
1772 *
1773 * What if we modelled the unlinked list as a collection of records capturing
1774 * "X.next_unlinked = Y" relations? If we indexed those records on Y, we'd
1775 * have a fast way to look up unlinked list predecessors, which avoids the
1776 * slow list walk. That's exactly what we do here (in-core) with a per-AG
1777 * rhashtable.
1778 *
1779 * Because this is a backref cache, we ignore operational failures since the
1780 * iunlink code can fall back to the slow bucket walk. The only errors that
1781 * should bubble out are for obviously incorrect situations.
1782 *
1783 * All users of the backref cache MUST hold the AGI buffer lock to serialize
1784 * access or have otherwise provided for concurrency control.
1785 */
1786
1787/* Capture a "X.next_unlinked = Y" relationship. */
1788struct xfs_iunlink {
1789 struct rhash_head iu_rhash_head;
1790 xfs_agino_t iu_agino; /* X */
1791 xfs_agino_t iu_next_unlinked; /* Y */
1792};
1793
1794/* Unlinked list predecessor lookup hashtable construction */
1795static int
1796xfs_iunlink_obj_cmpfn(
1797 struct rhashtable_compare_arg *arg,
1798 const void *obj)
1799{
1800 const xfs_agino_t *key = arg->key;
1801 const struct xfs_iunlink *iu = obj;
1802
1803 if (iu->iu_next_unlinked != *key)
1804 return 1;
1805 return 0;
1806}
1807
1808static const struct rhashtable_params xfs_iunlink_hash_params = {
1809 .min_size = XFS_AGI_UNLINKED_BUCKETS,
1810 .key_len = sizeof(xfs_agino_t),
1811 .key_offset = offsetof(struct xfs_iunlink,
1812 iu_next_unlinked),
1813 .head_offset = offsetof(struct xfs_iunlink, iu_rhash_head),
1814 .automatic_shrinking = true,
1815 .obj_cmpfn = xfs_iunlink_obj_cmpfn,
1816};
1817
1818/*
1819 * Return X, where X.next_unlinked == @agino. Returns NULLAGINO if no such
1820 * relation is found.
1821 */
1822static xfs_agino_t
1823xfs_iunlink_lookup_backref(
1824 struct xfs_perag *pag,
1825 xfs_agino_t agino)
1826{
1827 struct xfs_iunlink *iu;
1828
1829 iu = rhashtable_lookup_fast(&pag->pagi_unlinked_hash, &agino,
1830 xfs_iunlink_hash_params);
1831 return iu ? iu->iu_agino : NULLAGINO;
1832}
1833
1834/*
1835 * Take ownership of an iunlink cache entry and insert it into the hash table.
1836 * If successful, the entry will be owned by the cache; if not, it is freed.
1837 * Either way, the caller does not own @iu after this call.
1838 */
1839static int
1840xfs_iunlink_insert_backref(
1841 struct xfs_perag *pag,
1842 struct xfs_iunlink *iu)
1843{
1844 int error;
1845
1846 error = rhashtable_insert_fast(&pag->pagi_unlinked_hash,
1847 &iu->iu_rhash_head, xfs_iunlink_hash_params);
1848 /*
1849 * Fail loudly if there already was an entry because that's a sign of
1850 * corruption of in-memory data. Also fail loudly if we see an error
1851 * code we didn't anticipate from the rhashtable code. Currently we
1852 * only anticipate ENOMEM.
1853 */
1854 if (error) {
1855 WARN(error != -ENOMEM, "iunlink cache insert error %d", error);
1856 kmem_free(iu);
1857 }
1858 /*
1859 * Absorb any runtime errors that aren't a result of corruption because
1860 * this is a cache and we can always fall back to bucket list scanning.
1861 */
1862 if (error != 0 && error != -EEXIST)
1863 error = 0;
1864 return error;
1865}
1866
1867/* Remember that @prev_agino.next_unlinked = @this_agino. */
1868static int
1869xfs_iunlink_add_backref(
1870 struct xfs_perag *pag,
1871 xfs_agino_t prev_agino,
1872 xfs_agino_t this_agino)
1873{
1874 struct xfs_iunlink *iu;
1875
1876 if (XFS_TEST_ERROR(false, pag->pag_mount, XFS_ERRTAG_IUNLINK_FALLBACK))
1877 return 0;
1878
1879 iu = kmem_zalloc(sizeof(*iu), KM_NOFS);
1880 iu->iu_agino = prev_agino;
1881 iu->iu_next_unlinked = this_agino;
1882
1883 return xfs_iunlink_insert_backref(pag, iu);
1884}
1885
1886/*
1887 * Replace X.next_unlinked = @agino with X.next_unlinked = @next_unlinked.
1888 * If @next_unlinked is NULLAGINO, we drop the backref and exit. If there
1889 * wasn't any such entry then we don't bother.
1890 */
1891static int
1892xfs_iunlink_change_backref(
1893 struct xfs_perag *pag,
1894 xfs_agino_t agino,
1895 xfs_agino_t next_unlinked)
1896{
1897 struct xfs_iunlink *iu;
1898 int error;
1899
1900 /* Look up the old entry; if there wasn't one then exit. */
1901 iu = rhashtable_lookup_fast(&pag->pagi_unlinked_hash, &agino,
1902 xfs_iunlink_hash_params);
1903 if (!iu)
1904 return 0;
1905
1906 /*
1907 * Remove the entry. This shouldn't ever return an error, but if we
1908 * couldn't remove the old entry we don't want to add it again to the
1909 * hash table, and if the entry disappeared on us then someone's
1910 * violated the locking rules and we need to fail loudly. Either way
1911 * we cannot remove the inode because internal state is or would have
1912 * been corrupt.
1913 */
1914 error = rhashtable_remove_fast(&pag->pagi_unlinked_hash,
1915 &iu->iu_rhash_head, xfs_iunlink_hash_params);
1916 if (error)
1917 return error;
1918
1919 /* If there is no new next entry just free our item and return. */
1920 if (next_unlinked == NULLAGINO) {
1921 kmem_free(iu);
1922 return 0;
1923 }
1924
1925 /* Update the entry and re-add it to the hash table. */
1926 iu->iu_next_unlinked = next_unlinked;
1927 return xfs_iunlink_insert_backref(pag, iu);
1928}
1929
1930/* Set up the in-core predecessor structures. */
1931int
1932xfs_iunlink_init(
1933 struct xfs_perag *pag)
1934{
1935 return rhashtable_init(&pag->pagi_unlinked_hash,
1936 &xfs_iunlink_hash_params);
1937}
1938
1939/* Free the in-core predecessor structures. */
1940static void
1941xfs_iunlink_free_item(
1942 void *ptr,
1943 void *arg)
1944{
1945 struct xfs_iunlink *iu = ptr;
1946 bool *freed_anything = arg;
1947
1948 *freed_anything = true;
1949 kmem_free(iu);
1950}
1951
1952void
1953xfs_iunlink_destroy(
1954 struct xfs_perag *pag)
1955{
1956 bool freed_anything = false;
1957
1958 rhashtable_free_and_destroy(&pag->pagi_unlinked_hash,
1959 xfs_iunlink_free_item, &freed_anything);
1960
1961 ASSERT(freed_anything == false || XFS_FORCED_SHUTDOWN(pag->pag_mount));
1962}
1963
1964/*
1965 * Point the AGI unlinked bucket at an inode and log the results. The caller
1966 * is responsible for validating the old value.
1967 */
1968STATIC int
1969xfs_iunlink_update_bucket(
1970 struct xfs_trans *tp,
1971 struct xfs_perag *pag,
1972 struct xfs_buf *agibp,
1973 unsigned int bucket_index,
1974 xfs_agino_t new_agino)
1975{
1976 struct xfs_agi *agi = agibp->b_addr;
1977 xfs_agino_t old_value;
1978 int offset;
1979
1980 ASSERT(xfs_verify_agino_or_null(tp->t_mountp, pag->pag_agno, new_agino));
1981
1982 old_value = be32_to_cpu(agi->agi_unlinked[bucket_index]);
1983 trace_xfs_iunlink_update_bucket(tp->t_mountp, pag->pag_agno, bucket_index,
1984 old_value, new_agino);
1985
1986 /*
1987 * We should never find the head of the list already set to the value
1988 * passed in because either we're adding or removing ourselves from the
1989 * head of the list.
1990 */
1991 if (old_value == new_agino) {
1992 xfs_buf_mark_corrupt(agibp);
1993 return -EFSCORRUPTED;
1994 }
1995
1996 agi->agi_unlinked[bucket_index] = cpu_to_be32(new_agino);
1997 offset = offsetof(struct xfs_agi, agi_unlinked) +
1998 (sizeof(xfs_agino_t) * bucket_index);
1999 xfs_trans_log_buf(tp, agibp, offset, offset + sizeof(xfs_agino_t) - 1);
2000 return 0;
2001}
2002
2003/* Set an on-disk inode's next_unlinked pointer. */
2004STATIC void
2005xfs_iunlink_update_dinode(
2006 struct xfs_trans *tp,
2007 struct xfs_perag *pag,
2008 xfs_agino_t agino,
2009 struct xfs_buf *ibp,
2010 struct xfs_dinode *dip,
2011 struct xfs_imap *imap,
2012 xfs_agino_t next_agino)
2013{
2014 struct xfs_mount *mp = tp->t_mountp;
2015 int offset;
2016
2017 ASSERT(xfs_verify_agino_or_null(mp, pag->pag_agno, next_agino));
2018
2019 trace_xfs_iunlink_update_dinode(mp, pag->pag_agno, agino,
2020 be32_to_cpu(dip->di_next_unlinked), next_agino);
2021
2022 dip->di_next_unlinked = cpu_to_be32(next_agino);
2023 offset = imap->im_boffset +
2024 offsetof(struct xfs_dinode, di_next_unlinked);
2025
2026 /* need to recalc the inode CRC if appropriate */
2027 xfs_dinode_calc_crc(mp, dip);
2028 xfs_trans_inode_buf(tp, ibp);
2029 xfs_trans_log_buf(tp, ibp, offset, offset + sizeof(xfs_agino_t) - 1);
2030}
2031
2032/* Set an in-core inode's unlinked pointer and return the old value. */
2033STATIC int
2034xfs_iunlink_update_inode(
2035 struct xfs_trans *tp,
2036 struct xfs_inode *ip,
2037 struct xfs_perag *pag,
2038 xfs_agino_t next_agino,
2039 xfs_agino_t *old_next_agino)
2040{
2041 struct xfs_mount *mp = tp->t_mountp;
2042 struct xfs_dinode *dip;
2043 struct xfs_buf *ibp;
2044 xfs_agino_t old_value;
2045 int error;
2046
2047 ASSERT(xfs_verify_agino_or_null(mp, pag->pag_agno, next_agino));
2048
2049 error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &ibp);
2050 if (error)
2051 return error;
2052 dip = xfs_buf_offset(ibp, ip->i_imap.im_boffset);
2053
2054 /* Make sure the old pointer isn't garbage. */
2055 old_value = be32_to_cpu(dip->di_next_unlinked);
2056 if (!xfs_verify_agino_or_null(mp, pag->pag_agno, old_value)) {
2057 xfs_inode_verifier_error(ip, -EFSCORRUPTED, __func__, dip,
2058 sizeof(*dip), __this_address);
2059 error = -EFSCORRUPTED;
2060 goto out;
2061 }
2062
2063 /*
2064 * Since we're updating a linked list, we should never find that the
2065 * current pointer is the same as the new value, unless we're
2066 * terminating the list.
2067 */
2068 *old_next_agino = old_value;
2069 if (old_value == next_agino) {
2070 if (next_agino != NULLAGINO) {
2071 xfs_inode_verifier_error(ip, -EFSCORRUPTED, __func__,
2072 dip, sizeof(*dip), __this_address);
2073 error = -EFSCORRUPTED;
2074 }
2075 goto out;
2076 }
2077
2078 /* Ok, update the new pointer. */
2079 xfs_iunlink_update_dinode(tp, pag, XFS_INO_TO_AGINO(mp, ip->i_ino),
2080 ibp, dip, &ip->i_imap, next_agino);
2081 return 0;
2082out:
2083 xfs_trans_brelse(tp, ibp);
2084 return error;
2085}
2086
2087/*
2088 * This is called when the inode's link count has gone to 0 or we are creating
2089 * a tmpfile via O_TMPFILE. The inode @ip must have nlink == 0.
2090 *
2091 * We place the on-disk inode on a list in the AGI. It will be pulled from this
2092 * list when the inode is freed.
2093 */
2094STATIC int
2095xfs_iunlink(
2096 struct xfs_trans *tp,
2097 struct xfs_inode *ip)
2098{
2099 struct xfs_mount *mp = tp->t_mountp;
2100 struct xfs_perag *pag;
2101 struct xfs_agi *agi;
2102 struct xfs_buf *agibp;
2103 xfs_agino_t next_agino;
2104 xfs_agino_t agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
2105 short bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
2106 int error;
2107
2108 ASSERT(VFS_I(ip)->i_nlink == 0);
2109 ASSERT(VFS_I(ip)->i_mode != 0);
2110 trace_xfs_iunlink(ip);
2111
2112 pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));
2113
2114 /* Get the agi buffer first. It ensures lock ordering on the list. */
2115 error = xfs_read_agi(mp, tp, pag->pag_agno, &agibp);
2116 if (error)
2117 goto out;
2118 agi = agibp->b_addr;
2119
2120 /*
2121 * Get the index into the agi hash table for the list this inode will
2122 * go on. Make sure the pointer isn't garbage and that this inode
2123 * isn't already on the list.
2124 */
2125 next_agino = be32_to_cpu(agi->agi_unlinked[bucket_index]);
2126 if (next_agino == agino ||
2127 !xfs_verify_agino_or_null(mp, pag->pag_agno, next_agino)) {
2128 xfs_buf_mark_corrupt(agibp);
2129 error = -EFSCORRUPTED;
2130 goto out;
2131 }
2132
2133 if (next_agino != NULLAGINO) {
2134 xfs_agino_t old_agino;
2135
2136 /*
2137 * There is already another inode in the bucket, so point this
2138 * inode to the current head of the list.
2139 */
2140 error = xfs_iunlink_update_inode(tp, ip, pag, next_agino,
2141 &old_agino);
2142 if (error)
2143 goto out;
2144 ASSERT(old_agino == NULLAGINO);
2145
2146 /*
2147 * agino has been unlinked, add a backref from the next inode
2148 * back to agino.
2149 */
2150 error = xfs_iunlink_add_backref(pag, agino, next_agino);
2151 if (error)
2152 goto out;
2153 }
2154
2155 /* Point the head of the list to point to this inode. */
2156 error = xfs_iunlink_update_bucket(tp, pag, agibp, bucket_index, agino);
2157out:
2158 xfs_perag_put(pag);
2159 return error;
2160}
2161
2162/* Return the imap, dinode pointer, and buffer for an inode. */
2163STATIC int
2164xfs_iunlink_map_ino(
2165 struct xfs_trans *tp,
2166 xfs_agnumber_t agno,
2167 xfs_agino_t agino,
2168 struct xfs_imap *imap,
2169 struct xfs_dinode **dipp,
2170 struct xfs_buf **bpp)
2171{
2172 struct xfs_mount *mp = tp->t_mountp;
2173 int error;
2174
2175 imap->im_blkno = 0;
2176 error = xfs_imap(mp, tp, XFS_AGINO_TO_INO(mp, agno, agino), imap, 0);
2177 if (error) {
2178 xfs_warn(mp, "%s: xfs_imap returned error %d.",
2179 __func__, error);
2180 return error;
2181 }
2182
2183 error = xfs_imap_to_bp(mp, tp, imap, bpp);
2184 if (error) {
2185 xfs_warn(mp, "%s: xfs_imap_to_bp returned error %d.",
2186 __func__, error);
2187 return error;
2188 }
2189
2190 *dipp = xfs_buf_offset(*bpp, imap->im_boffset);
2191 return 0;
2192}
2193
2194/*
2195 * Walk the unlinked chain from @head_agino until we find the inode that
2196 * points to @target_agino. Return the inode number, map, dinode pointer,
2197 * and inode cluster buffer of that inode as @agino, @imap, @dipp, and @bpp.
2198 *
2199 * @tp, @pag, @head_agino, and @target_agino are input parameters.
2200 * @agino, @imap, @dipp, and @bpp are all output parameters.
2201 *
2202 * Do not call this function if @target_agino is the head of the list.
2203 */
2204STATIC int
2205xfs_iunlink_map_prev(
2206 struct xfs_trans *tp,
2207 struct xfs_perag *pag,
2208 xfs_agino_t head_agino,
2209 xfs_agino_t target_agino,
2210 xfs_agino_t *agino,
2211 struct xfs_imap *imap,
2212 struct xfs_dinode **dipp,
2213 struct xfs_buf **bpp)
2214{
2215 struct xfs_mount *mp = tp->t_mountp;
2216 xfs_agino_t next_agino;
2217 int error;
2218
2219 ASSERT(head_agino != target_agino);
2220 *bpp = NULL;
2221
2222 /* See if our backref cache can find it faster. */
2223 *agino = xfs_iunlink_lookup_backref(pag, target_agino);
2224 if (*agino != NULLAGINO) {
2225 error = xfs_iunlink_map_ino(tp, pag->pag_agno, *agino, imap,
2226 dipp, bpp);
2227 if (error)
2228 return error;
2229
2230 if (be32_to_cpu((*dipp)->di_next_unlinked) == target_agino)
2231 return 0;
2232
2233 /*
2234 * If we get here the cache contents were corrupt, so drop the
2235 * buffer and fall back to walking the bucket list.
2236 */
2237 xfs_trans_brelse(tp, *bpp);
2238 *bpp = NULL;
2239 WARN_ON_ONCE(1);
2240 }
2241
2242 trace_xfs_iunlink_map_prev_fallback(mp, pag->pag_agno);
2243
2244 /* Otherwise, walk the entire bucket until we find it. */
2245 next_agino = head_agino;
2246 while (next_agino != target_agino) {
2247 xfs_agino_t unlinked_agino;
2248
2249 if (*bpp)
2250 xfs_trans_brelse(tp, *bpp);
2251
2252 *agino = next_agino;
2253 error = xfs_iunlink_map_ino(tp, pag->pag_agno, next_agino, imap,
2254 dipp, bpp);
2255 if (error)
2256 return error;
2257
2258 unlinked_agino = be32_to_cpu((*dipp)->di_next_unlinked);
2259 /*
2260 * Make sure this pointer is valid and isn't an obvious
2261 * infinite loop.
2262 */
2263 if (!xfs_verify_agino(mp, pag->pag_agno, unlinked_agino) ||
2264 next_agino == unlinked_agino) {
2265 XFS_CORRUPTION_ERROR(__func__,
2266 XFS_ERRLEVEL_LOW, mp,
2267 *dipp, sizeof(**dipp));
2268 error = -EFSCORRUPTED;
2269 return error;
2270 }
2271 next_agino = unlinked_agino;
2272 }
2273
2274 return 0;
2275}
2276
2277/*
2278 * Pull the on-disk inode from the AGI unlinked list.
2279 */
2280STATIC int
2281xfs_iunlink_remove(
2282 struct xfs_trans *tp,
2283 struct xfs_perag *pag,
2284 struct xfs_inode *ip)
2285{
2286 struct xfs_mount *mp = tp->t_mountp;
2287 struct xfs_agi *agi;
2288 struct xfs_buf *agibp;
2289 struct xfs_buf *last_ibp;
2290 struct xfs_dinode *last_dip = NULL;
2291 xfs_agino_t agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
2292 xfs_agino_t next_agino;
2293 xfs_agino_t head_agino;
2294 short bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
2295 int error;
2296
2297 trace_xfs_iunlink_remove(ip);
2298
2299 /* Get the agi buffer first. It ensures lock ordering on the list. */
2300 error = xfs_read_agi(mp, tp, pag->pag_agno, &agibp);
2301 if (error)
2302 return error;
2303 agi = agibp->b_addr;
2304
2305 /*
2306 * Get the index into the agi hash table for the list this inode will
2307 * go on. Make sure the head pointer isn't garbage.
2308 */
2309 head_agino = be32_to_cpu(agi->agi_unlinked[bucket_index]);
2310 if (!xfs_verify_agino(mp, pag->pag_agno, head_agino)) {
2311 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
2312 agi, sizeof(*agi));
2313 return -EFSCORRUPTED;
2314 }
2315
2316 /*
2317 * Set our inode's next_unlinked pointer to NULL and then return
2318 * the old pointer value so that we can update whatever was previous
2319 * to us in the list to point to whatever was next in the list.
2320 */
2321 error = xfs_iunlink_update_inode(tp, ip, pag, NULLAGINO, &next_agino);
2322 if (error)
2323 return error;
2324
2325 /*
2326 * If there was a backref pointing from the next inode back to this
2327 * one, remove it because we've removed this inode from the list.
2328 *
2329 * Later, if this inode was in the middle of the list we'll update
2330 * this inode's backref to point from the next inode.
2331 */
2332 if (next_agino != NULLAGINO) {
2333 error = xfs_iunlink_change_backref(pag, next_agino, NULLAGINO);
2334 if (error)
2335 return error;
2336 }
2337
2338 if (head_agino != agino) {
2339 struct xfs_imap imap;
2340 xfs_agino_t prev_agino;
2341
2342 /* We need to search the list for the inode being freed. */
2343 error = xfs_iunlink_map_prev(tp, pag, head_agino, agino,
2344 &prev_agino, &imap, &last_dip, &last_ibp);
2345 if (error)
2346 return error;
2347
2348 /* Point the previous inode on the list to the next inode. */
2349 xfs_iunlink_update_dinode(tp, pag, prev_agino, last_ibp,
2350 last_dip, &imap, next_agino);
2351
2352 /*
2353 * Now we deal with the backref for this inode. If this inode
2354 * pointed at a real inode, change the backref that pointed to
2355 * us to point to our old next. If this inode was the end of
2356 * the list, delete the backref that pointed to us. Note that
2357 * change_backref takes care of deleting the backref if
2358 * next_agino is NULLAGINO.
2359 */
2360 return xfs_iunlink_change_backref(agibp->b_pag, agino,
2361 next_agino);
2362 }
2363
2364 /* Point the head of the list to the next unlinked inode. */
2365 return xfs_iunlink_update_bucket(tp, pag, agibp, bucket_index,
2366 next_agino);
2367}
2368
2369/*
2370 * Look up the inode number specified and if it is not already marked XFS_ISTALE
2371 * mark it stale. We should only find clean inodes in this lookup that aren't
2372 * already stale.
2373 */
2374static void
2375xfs_ifree_mark_inode_stale(
2376 struct xfs_perag *pag,
2377 struct xfs_inode *free_ip,
2378 xfs_ino_t inum)
2379{
2380 struct xfs_mount *mp = pag->pag_mount;
2381 struct xfs_inode_log_item *iip;
2382 struct xfs_inode *ip;
2383
2384retry:
2385 rcu_read_lock();
2386 ip = radix_tree_lookup(&pag->pag_ici_root, XFS_INO_TO_AGINO(mp, inum));
2387
2388 /* Inode not in memory, nothing to do */
2389 if (!ip) {
2390 rcu_read_unlock();
2391 return;
2392 }
2393
2394 /*
2395 * because this is an RCU protected lookup, we could find a recently
2396 * freed or even reallocated inode during the lookup. We need to check
2397 * under the i_flags_lock for a valid inode here. Skip it if it is not
2398 * valid, the wrong inode or stale.
2399 */
2400 spin_lock(&ip->i_flags_lock);
2401 if (ip->i_ino != inum || __xfs_iflags_test(ip, XFS_ISTALE))
2402 goto out_iflags_unlock;
2403
2404 /*
2405 * Don't try to lock/unlock the current inode, but we _cannot_ skip the
2406 * other inodes that we did not find in the list attached to the buffer
2407 * and are not already marked stale. If we can't lock it, back off and
2408 * retry.
2409 */
2410 if (ip != free_ip) {
2411 if (!xfs_ilock_nowait(ip, XFS_ILOCK_EXCL)) {
2412 spin_unlock(&ip->i_flags_lock);
2413 rcu_read_unlock();
2414 delay(1);
2415 goto retry;
2416 }
2417 }
2418 ip->i_flags |= XFS_ISTALE;
2419
2420 /*
2421 * If the inode is flushing, it is already attached to the buffer. All
2422 * we needed to do here is mark the inode stale so buffer IO completion
2423 * will remove it from the AIL.
2424 */
2425 iip = ip->i_itemp;
2426 if (__xfs_iflags_test(ip, XFS_IFLUSHING)) {
2427 ASSERT(!list_empty(&iip->ili_item.li_bio_list));
2428 ASSERT(iip->ili_last_fields);
2429 goto out_iunlock;
2430 }
2431
2432 /*
2433 * Inodes not attached to the buffer can be released immediately.
2434 * Everything else has to go through xfs_iflush_abort() on journal
2435 * commit as the flock synchronises removal of the inode from the
2436 * cluster buffer against inode reclaim.
2437 */
2438 if (!iip || list_empty(&iip->ili_item.li_bio_list))
2439 goto out_iunlock;
2440
2441 __xfs_iflags_set(ip, XFS_IFLUSHING);
2442 spin_unlock(&ip->i_flags_lock);
2443 rcu_read_unlock();
2444
2445 /* we have a dirty inode in memory that has not yet been flushed. */
2446 spin_lock(&iip->ili_lock);
2447 iip->ili_last_fields = iip->ili_fields;
2448 iip->ili_fields = 0;
2449 iip->ili_fsync_fields = 0;
2450 spin_unlock(&iip->ili_lock);
2451 ASSERT(iip->ili_last_fields);
2452
2453 if (ip != free_ip)
2454 xfs_iunlock(ip, XFS_ILOCK_EXCL);
2455 return;
2456
2457out_iunlock:
2458 if (ip != free_ip)
2459 xfs_iunlock(ip, XFS_ILOCK_EXCL);
2460out_iflags_unlock:
2461 spin_unlock(&ip->i_flags_lock);
2462 rcu_read_unlock();
2463}
2464
2465/*
2466 * A big issue when freeing the inode cluster is that we _cannot_ skip any
2467 * inodes that are in memory - they all must be marked stale and attached to
2468 * the cluster buffer.
2469 */
2470static int
2471xfs_ifree_cluster(
2472 struct xfs_trans *tp,
2473 struct xfs_perag *pag,
2474 struct xfs_inode *free_ip,
2475 struct xfs_icluster *xic)
2476{
2477 struct xfs_mount *mp = free_ip->i_mount;
2478 struct xfs_ino_geometry *igeo = M_IGEO(mp);
2479 struct xfs_buf *bp;
2480 xfs_daddr_t blkno;
2481 xfs_ino_t inum = xic->first_ino;
2482 int nbufs;
2483 int i, j;
2484 int ioffset;
2485 int error;
2486
2487 nbufs = igeo->ialloc_blks / igeo->blocks_per_cluster;
2488
2489 for (j = 0; j < nbufs; j++, inum += igeo->inodes_per_cluster) {
2490 /*
2491 * The allocation bitmap tells us which inodes of the chunk were
2492 * physically allocated. Skip the cluster if an inode falls into
2493 * a sparse region.
2494 */
2495 ioffset = inum - xic->first_ino;
2496 if ((xic->alloc & XFS_INOBT_MASK(ioffset)) == 0) {
2497 ASSERT(ioffset % igeo->inodes_per_cluster == 0);
2498 continue;
2499 }
2500
2501 blkno = XFS_AGB_TO_DADDR(mp, XFS_INO_TO_AGNO(mp, inum),
2502 XFS_INO_TO_AGBNO(mp, inum));
2503
2504 /*
2505 * We obtain and lock the backing buffer first in the process
2506 * here to ensure dirty inodes attached to the buffer remain in
2507 * the flushing state while we mark them stale.
2508 *
2509 * If we scan the in-memory inodes first, then buffer IO can
2510 * complete before we get a lock on it, and hence we may fail
2511 * to mark all the active inodes on the buffer stale.
2512 */
2513 error = xfs_trans_get_buf(tp, mp->m_ddev_targp, blkno,
2514 mp->m_bsize * igeo->blocks_per_cluster,
2515 XBF_UNMAPPED, &bp);
2516 if (error)
2517 return error;
2518
2519 /*
2520 * This buffer may not have been correctly initialised as we
2521 * didn't read it from disk. That's not important because we are
2522 * only using to mark the buffer as stale in the log, and to
2523 * attach stale cached inodes on it. That means it will never be
2524 * dispatched for IO. If it is, we want to know about it, and we
2525 * want it to fail. We can acheive this by adding a write
2526 * verifier to the buffer.
2527 */
2528 bp->b_ops = &xfs_inode_buf_ops;
2529
2530 /*
2531 * Now we need to set all the cached clean inodes as XFS_ISTALE,
2532 * too. This requires lookups, and will skip inodes that we've
2533 * already marked XFS_ISTALE.
2534 */
2535 for (i = 0; i < igeo->inodes_per_cluster; i++)
2536 xfs_ifree_mark_inode_stale(pag, free_ip, inum + i);
2537
2538 xfs_trans_stale_inode_buf(tp, bp);
2539 xfs_trans_binval(tp, bp);
2540 }
2541 return 0;
2542}
2543
2544/*
2545 * This is called to return an inode to the inode free list.
2546 * The inode should already be truncated to 0 length and have
2547 * no pages associated with it. This routine also assumes that
2548 * the inode is already a part of the transaction.
2549 *
2550 * The on-disk copy of the inode will have been added to the list
2551 * of unlinked inodes in the AGI. We need to remove the inode from
2552 * that list atomically with respect to freeing it here.
2553 */
2554int
2555xfs_ifree(
2556 struct xfs_trans *tp,
2557 struct xfs_inode *ip)
2558{
2559 struct xfs_mount *mp = ip->i_mount;
2560 struct xfs_perag *pag;
2561 struct xfs_icluster xic = { 0 };
2562 struct xfs_inode_log_item *iip = ip->i_itemp;
2563 int error;
2564
2565 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
2566 ASSERT(VFS_I(ip)->i_nlink == 0);
2567 ASSERT(ip->i_df.if_nextents == 0);
2568 ASSERT(ip->i_disk_size == 0 || !S_ISREG(VFS_I(ip)->i_mode));
2569 ASSERT(ip->i_nblocks == 0);
2570
2571 pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));
2572
2573 /*
2574 * Pull the on-disk inode from the AGI unlinked list.
2575 */
2576 error = xfs_iunlink_remove(tp, pag, ip);
2577 if (error)
2578 goto out;
2579
2580 error = xfs_difree(tp, pag, ip->i_ino, &xic);
2581 if (error)
2582 goto out;
2583
2584 /*
2585 * Free any local-format data sitting around before we reset the
2586 * data fork to extents format. Note that the attr fork data has
2587 * already been freed by xfs_attr_inactive.
2588 */
2589 if (ip->i_df.if_format == XFS_DINODE_FMT_LOCAL) {
2590 kmem_free(ip->i_df.if_u1.if_data);
2591 ip->i_df.if_u1.if_data = NULL;
2592 ip->i_df.if_bytes = 0;
2593 }
2594
2595 VFS_I(ip)->i_mode = 0; /* mark incore inode as free */
2596 ip->i_diflags = 0;
2597 ip->i_diflags2 = mp->m_ino_geo.new_diflags2;
2598 ip->i_forkoff = 0; /* mark the attr fork not in use */
2599 ip->i_df.if_format = XFS_DINODE_FMT_EXTENTS;
2600 if (xfs_iflags_test(ip, XFS_IPRESERVE_DM_FIELDS))
2601 xfs_iflags_clear(ip, XFS_IPRESERVE_DM_FIELDS);
2602
2603 /* Don't attempt to replay owner changes for a deleted inode */
2604 spin_lock(&iip->ili_lock);
2605 iip->ili_fields &= ~(XFS_ILOG_AOWNER | XFS_ILOG_DOWNER);
2606 spin_unlock(&iip->ili_lock);
2607
2608 /*
2609 * Bump the generation count so no one will be confused
2610 * by reincarnations of this inode.
2611 */
2612 VFS_I(ip)->i_generation++;
2613 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
2614
2615 if (xic.deleted)
2616 error = xfs_ifree_cluster(tp, pag, ip, &xic);
2617out:
2618 xfs_perag_put(pag);
2619 return error;
2620}
2621
2622/*
2623 * This is called to unpin an inode. The caller must have the inode locked
2624 * in at least shared mode so that the buffer cannot be subsequently pinned
2625 * once someone is waiting for it to be unpinned.
2626 */
2627static void
2628xfs_iunpin(
2629 struct xfs_inode *ip)
2630{
2631 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
2632
2633 trace_xfs_inode_unpin_nowait(ip, _RET_IP_);
2634
2635 /* Give the log a push to start the unpinning I/O */
2636 xfs_log_force_seq(ip->i_mount, ip->i_itemp->ili_commit_seq, 0, NULL);
2637
2638}
2639
2640static void
2641__xfs_iunpin_wait(
2642 struct xfs_inode *ip)
2643{
2644 wait_queue_head_t *wq = bit_waitqueue(&ip->i_flags, __XFS_IPINNED_BIT);
2645 DEFINE_WAIT_BIT(wait, &ip->i_flags, __XFS_IPINNED_BIT);
2646
2647 xfs_iunpin(ip);
2648
2649 do {
2650 prepare_to_wait(wq, &wait.wq_entry, TASK_UNINTERRUPTIBLE);
2651 if (xfs_ipincount(ip))
2652 io_schedule();
2653 } while (xfs_ipincount(ip));
2654 finish_wait(wq, &wait.wq_entry);
2655}
2656
2657void
2658xfs_iunpin_wait(
2659 struct xfs_inode *ip)
2660{
2661 if (xfs_ipincount(ip))
2662 __xfs_iunpin_wait(ip);
2663}
2664
2665/*
2666 * Removing an inode from the namespace involves removing the directory entry
2667 * and dropping the link count on the inode. Removing the directory entry can
2668 * result in locking an AGF (directory blocks were freed) and removing a link
2669 * count can result in placing the inode on an unlinked list which results in
2670 * locking an AGI.
2671 *
2672 * The big problem here is that we have an ordering constraint on AGF and AGI
2673 * locking - inode allocation locks the AGI, then can allocate a new extent for
2674 * new inodes, locking the AGF after the AGI. Similarly, freeing the inode
2675 * removes the inode from the unlinked list, requiring that we lock the AGI
2676 * first, and then freeing the inode can result in an inode chunk being freed
2677 * and hence freeing disk space requiring that we lock an AGF.
2678 *
2679 * Hence the ordering that is imposed by other parts of the code is AGI before
2680 * AGF. This means we cannot remove the directory entry before we drop the inode
2681 * reference count and put it on the unlinked list as this results in a lock
2682 * order of AGF then AGI, and this can deadlock against inode allocation and
2683 * freeing. Therefore we must drop the link counts before we remove the
2684 * directory entry.
2685 *
2686 * This is still safe from a transactional point of view - it is not until we
2687 * get to xfs_defer_finish() that we have the possibility of multiple
2688 * transactions in this operation. Hence as long as we remove the directory
2689 * entry and drop the link count in the first transaction of the remove
2690 * operation, there are no transactional constraints on the ordering here.
2691 */
2692int
2693xfs_remove(
2694 xfs_inode_t *dp,
2695 struct xfs_name *name,
2696 xfs_inode_t *ip)
2697{
2698 xfs_mount_t *mp = dp->i_mount;
2699 xfs_trans_t *tp = NULL;
2700 int is_dir = S_ISDIR(VFS_I(ip)->i_mode);
2701 int error = 0;
2702 uint resblks;
2703
2704 trace_xfs_remove(dp, name);
2705
2706 if (XFS_FORCED_SHUTDOWN(mp))
2707 return -EIO;
2708
2709 error = xfs_qm_dqattach(dp);
2710 if (error)
2711 goto std_return;
2712
2713 error = xfs_qm_dqattach(ip);
2714 if (error)
2715 goto std_return;
2716
2717 /*
2718 * We try to get the real space reservation first,
2719 * allowing for directory btree deletion(s) implying
2720 * possible bmap insert(s). If we can't get the space
2721 * reservation then we use 0 instead, and avoid the bmap
2722 * btree insert(s) in the directory code by, if the bmap
2723 * insert tries to happen, instead trimming the LAST
2724 * block from the directory.
2725 */
2726 resblks = XFS_REMOVE_SPACE_RES(mp);
2727 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_remove, resblks, 0, 0, &tp);
2728 if (error == -ENOSPC) {
2729 resblks = 0;
2730 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_remove, 0, 0, 0,
2731 &tp);
2732 }
2733 if (error) {
2734 ASSERT(error != -ENOSPC);
2735 goto std_return;
2736 }
2737
2738 xfs_lock_two_inodes(dp, XFS_ILOCK_EXCL, ip, XFS_ILOCK_EXCL);
2739
2740 xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
2741 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
2742
2743 /*
2744 * If we're removing a directory perform some additional validation.
2745 */
2746 if (is_dir) {
2747 ASSERT(VFS_I(ip)->i_nlink >= 2);
2748 if (VFS_I(ip)->i_nlink != 2) {
2749 error = -ENOTEMPTY;
2750 goto out_trans_cancel;
2751 }
2752 if (!xfs_dir_isempty(ip)) {
2753 error = -ENOTEMPTY;
2754 goto out_trans_cancel;
2755 }
2756
2757 /* Drop the link from ip's "..". */
2758 error = xfs_droplink(tp, dp);
2759 if (error)
2760 goto out_trans_cancel;
2761
2762 /* Drop the "." link from ip to self. */
2763 error = xfs_droplink(tp, ip);
2764 if (error)
2765 goto out_trans_cancel;
2766
2767 /*
2768 * Point the unlinked child directory's ".." entry to the root
2769 * directory to eliminate back-references to inodes that may
2770 * get freed before the child directory is closed. If the fs
2771 * gets shrunk, this can lead to dirent inode validation errors.
2772 */
2773 if (dp->i_ino != tp->t_mountp->m_sb.sb_rootino) {
2774 error = xfs_dir_replace(tp, ip, &xfs_name_dotdot,
2775 tp->t_mountp->m_sb.sb_rootino, 0);
2776 if (error)
2777 return error;
2778 }
2779 } else {
2780 /*
2781 * When removing a non-directory we need to log the parent
2782 * inode here. For a directory this is done implicitly
2783 * by the xfs_droplink call for the ".." entry.
2784 */
2785 xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
2786 }
2787 xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2788
2789 /* Drop the link from dp to ip. */
2790 error = xfs_droplink(tp, ip);
2791 if (error)
2792 goto out_trans_cancel;
2793
2794 error = xfs_dir_removename(tp, dp, name, ip->i_ino, resblks);
2795 if (error) {
2796 ASSERT(error != -ENOENT);
2797 goto out_trans_cancel;
2798 }
2799
2800 /*
2801 * If this is a synchronous mount, make sure that the
2802 * remove transaction goes to disk before returning to
2803 * the user.
2804 */
2805 if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
2806 xfs_trans_set_sync(tp);
2807
2808 error = xfs_trans_commit(tp);
2809 if (error)
2810 goto std_return;
2811
2812 if (is_dir && xfs_inode_is_filestream(ip))
2813 xfs_filestream_deassociate(ip);
2814
2815 return 0;
2816
2817 out_trans_cancel:
2818 xfs_trans_cancel(tp);
2819 std_return:
2820 return error;
2821}
2822
2823/*
2824 * Enter all inodes for a rename transaction into a sorted array.
2825 */
2826#define __XFS_SORT_INODES 5
2827STATIC void
2828xfs_sort_for_rename(
2829 struct xfs_inode *dp1, /* in: old (source) directory inode */
2830 struct xfs_inode *dp2, /* in: new (target) directory inode */
2831 struct xfs_inode *ip1, /* in: inode of old entry */
2832 struct xfs_inode *ip2, /* in: inode of new entry */
2833 struct xfs_inode *wip, /* in: whiteout inode */
2834 struct xfs_inode **i_tab,/* out: sorted array of inodes */
2835 int *num_inodes) /* in/out: inodes in array */
2836{
2837 int i, j;
2838
2839 ASSERT(*num_inodes == __XFS_SORT_INODES);
2840 memset(i_tab, 0, *num_inodes * sizeof(struct xfs_inode *));
2841
2842 /*
2843 * i_tab contains a list of pointers to inodes. We initialize
2844 * the table here & we'll sort it. We will then use it to
2845 * order the acquisition of the inode locks.
2846 *
2847 * Note that the table may contain duplicates. e.g., dp1 == dp2.
2848 */
2849 i = 0;
2850 i_tab[i++] = dp1;
2851 i_tab[i++] = dp2;
2852 i_tab[i++] = ip1;
2853 if (ip2)
2854 i_tab[i++] = ip2;
2855 if (wip)
2856 i_tab[i++] = wip;
2857 *num_inodes = i;
2858
2859 /*
2860 * Sort the elements via bubble sort. (Remember, there are at
2861 * most 5 elements to sort, so this is adequate.)
2862 */
2863 for (i = 0; i < *num_inodes; i++) {
2864 for (j = 1; j < *num_inodes; j++) {
2865 if (i_tab[j]->i_ino < i_tab[j-1]->i_ino) {
2866 struct xfs_inode *temp = i_tab[j];
2867 i_tab[j] = i_tab[j-1];
2868 i_tab[j-1] = temp;
2869 }
2870 }
2871 }
2872}
2873
2874static int
2875xfs_finish_rename(
2876 struct xfs_trans *tp)
2877{
2878 /*
2879 * If this is a synchronous mount, make sure that the rename transaction
2880 * goes to disk before returning to the user.
2881 */
2882 if (tp->t_mountp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
2883 xfs_trans_set_sync(tp);
2884
2885 return xfs_trans_commit(tp);
2886}
2887
2888/*
2889 * xfs_cross_rename()
2890 *
2891 * responsible for handling RENAME_EXCHANGE flag in renameat2() syscall
2892 */
2893STATIC int
2894xfs_cross_rename(
2895 struct xfs_trans *tp,
2896 struct xfs_inode *dp1,
2897 struct xfs_name *name1,
2898 struct xfs_inode *ip1,
2899 struct xfs_inode *dp2,
2900 struct xfs_name *name2,
2901 struct xfs_inode *ip2,
2902 int spaceres)
2903{
2904 int error = 0;
2905 int ip1_flags = 0;
2906 int ip2_flags = 0;
2907 int dp2_flags = 0;
2908
2909 /* Swap inode number for dirent in first parent */
2910 error = xfs_dir_replace(tp, dp1, name1, ip2->i_ino, spaceres);
2911 if (error)
2912 goto out_trans_abort;
2913
2914 /* Swap inode number for dirent in second parent */
2915 error = xfs_dir_replace(tp, dp2, name2, ip1->i_ino, spaceres);
2916 if (error)
2917 goto out_trans_abort;
2918
2919 /*
2920 * If we're renaming one or more directories across different parents,
2921 * update the respective ".." entries (and link counts) to match the new
2922 * parents.
2923 */
2924 if (dp1 != dp2) {
2925 dp2_flags = XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
2926
2927 if (S_ISDIR(VFS_I(ip2)->i_mode)) {
2928 error = xfs_dir_replace(tp, ip2, &xfs_name_dotdot,
2929 dp1->i_ino, spaceres);
2930 if (error)
2931 goto out_trans_abort;
2932
2933 /* transfer ip2 ".." reference to dp1 */
2934 if (!S_ISDIR(VFS_I(ip1)->i_mode)) {
2935 error = xfs_droplink(tp, dp2);
2936 if (error)
2937 goto out_trans_abort;
2938 xfs_bumplink(tp, dp1);
2939 }
2940
2941 /*
2942 * Although ip1 isn't changed here, userspace needs
2943 * to be warned about the change, so that applications
2944 * relying on it (like backup ones), will properly
2945 * notify the change
2946 */
2947 ip1_flags |= XFS_ICHGTIME_CHG;
2948 ip2_flags |= XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
2949 }
2950
2951 if (S_ISDIR(VFS_I(ip1)->i_mode)) {
2952 error = xfs_dir_replace(tp, ip1, &xfs_name_dotdot,
2953 dp2->i_ino, spaceres);
2954 if (error)
2955 goto out_trans_abort;
2956
2957 /* transfer ip1 ".." reference to dp2 */
2958 if (!S_ISDIR(VFS_I(ip2)->i_mode)) {
2959 error = xfs_droplink(tp, dp1);
2960 if (error)
2961 goto out_trans_abort;
2962 xfs_bumplink(tp, dp2);
2963 }
2964
2965 /*
2966 * Although ip2 isn't changed here, userspace needs
2967 * to be warned about the change, so that applications
2968 * relying on it (like backup ones), will properly
2969 * notify the change
2970 */
2971 ip1_flags |= XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
2972 ip2_flags |= XFS_ICHGTIME_CHG;
2973 }
2974 }
2975
2976 if (ip1_flags) {
2977 xfs_trans_ichgtime(tp, ip1, ip1_flags);
2978 xfs_trans_log_inode(tp, ip1, XFS_ILOG_CORE);
2979 }
2980 if (ip2_flags) {
2981 xfs_trans_ichgtime(tp, ip2, ip2_flags);
2982 xfs_trans_log_inode(tp, ip2, XFS_ILOG_CORE);
2983 }
2984 if (dp2_flags) {
2985 xfs_trans_ichgtime(tp, dp2, dp2_flags);
2986 xfs_trans_log_inode(tp, dp2, XFS_ILOG_CORE);
2987 }
2988 xfs_trans_ichgtime(tp, dp1, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2989 xfs_trans_log_inode(tp, dp1, XFS_ILOG_CORE);
2990 return xfs_finish_rename(tp);
2991
2992out_trans_abort:
2993 xfs_trans_cancel(tp);
2994 return error;
2995}
2996
2997/*
2998 * xfs_rename_alloc_whiteout()
2999 *
3000 * Return a referenced, unlinked, unlocked inode that can be used as a
3001 * whiteout in a rename transaction. We use a tmpfile inode here so that if we
3002 * crash between allocating the inode and linking it into the rename transaction
3003 * recovery will free the inode and we won't leak it.
3004 */
3005static int
3006xfs_rename_alloc_whiteout(
3007 struct user_namespace *mnt_userns,
3008 struct xfs_inode *dp,
3009 struct xfs_inode **wip)
3010{
3011 struct xfs_inode *tmpfile;
3012 int error;
3013
3014 error = xfs_create_tmpfile(mnt_userns, dp, S_IFCHR | WHITEOUT_MODE,
3015 &tmpfile);
3016 if (error)
3017 return error;
3018
3019 /*
3020 * Prepare the tmpfile inode as if it were created through the VFS.
3021 * Complete the inode setup and flag it as linkable. nlink is already
3022 * zero, so we can skip the drop_nlink.
3023 */
3024 xfs_setup_iops(tmpfile);
3025 xfs_finish_inode_setup(tmpfile);
3026 VFS_I(tmpfile)->i_state |= I_LINKABLE;
3027
3028 *wip = tmpfile;
3029 return 0;
3030}
3031
3032/*
3033 * xfs_rename
3034 */
3035int
3036xfs_rename(
3037 struct user_namespace *mnt_userns,
3038 struct xfs_inode *src_dp,
3039 struct xfs_name *src_name,
3040 struct xfs_inode *src_ip,
3041 struct xfs_inode *target_dp,
3042 struct xfs_name *target_name,
3043 struct xfs_inode *target_ip,
3044 unsigned int flags)
3045{
3046 struct xfs_mount *mp = src_dp->i_mount;
3047 struct xfs_trans *tp;
3048 struct xfs_inode *wip = NULL; /* whiteout inode */
3049 struct xfs_inode *inodes[__XFS_SORT_INODES];
3050 int i;
3051 int num_inodes = __XFS_SORT_INODES;
3052 bool new_parent = (src_dp != target_dp);
3053 bool src_is_directory = S_ISDIR(VFS_I(src_ip)->i_mode);
3054 int spaceres;
3055 int error;
3056
3057 trace_xfs_rename(src_dp, target_dp, src_name, target_name);
3058
3059 if ((flags & RENAME_EXCHANGE) && !target_ip)
3060 return -EINVAL;
3061
3062 /*
3063 * If we are doing a whiteout operation, allocate the whiteout inode
3064 * we will be placing at the target and ensure the type is set
3065 * appropriately.
3066 */
3067 if (flags & RENAME_WHITEOUT) {
3068 ASSERT(!(flags & (RENAME_NOREPLACE | RENAME_EXCHANGE)));
3069 error = xfs_rename_alloc_whiteout(mnt_userns, target_dp, &wip);
3070 if (error)
3071 return error;
3072
3073 /* setup target dirent info as whiteout */
3074 src_name->type = XFS_DIR3_FT_CHRDEV;
3075 }
3076
3077 xfs_sort_for_rename(src_dp, target_dp, src_ip, target_ip, wip,
3078 inodes, &num_inodes);
3079
3080 spaceres = XFS_RENAME_SPACE_RES(mp, target_name->len);
3081 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_rename, spaceres, 0, 0, &tp);
3082 if (error == -ENOSPC) {
3083 spaceres = 0;
3084 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_rename, 0, 0, 0,
3085 &tp);
3086 }
3087 if (error)
3088 goto out_release_wip;
3089
3090 /*
3091 * Attach the dquots to the inodes
3092 */
3093 error = xfs_qm_vop_rename_dqattach(inodes);
3094 if (error)
3095 goto out_trans_cancel;
3096
3097 /*
3098 * Lock all the participating inodes. Depending upon whether
3099 * the target_name exists in the target directory, and
3100 * whether the target directory is the same as the source
3101 * directory, we can lock from 2 to 4 inodes.
3102 */
3103 xfs_lock_inodes(inodes, num_inodes, XFS_ILOCK_EXCL);
3104
3105 /*
3106 * Join all the inodes to the transaction. From this point on,
3107 * we can rely on either trans_commit or trans_cancel to unlock
3108 * them.
3109 */
3110 xfs_trans_ijoin(tp, src_dp, XFS_ILOCK_EXCL);
3111 if (new_parent)
3112 xfs_trans_ijoin(tp, target_dp, XFS_ILOCK_EXCL);
3113 xfs_trans_ijoin(tp, src_ip, XFS_ILOCK_EXCL);
3114 if (target_ip)
3115 xfs_trans_ijoin(tp, target_ip, XFS_ILOCK_EXCL);
3116 if (wip)
3117 xfs_trans_ijoin(tp, wip, XFS_ILOCK_EXCL);
3118
3119 /*
3120 * If we are using project inheritance, we only allow renames
3121 * into our tree when the project IDs are the same; else the
3122 * tree quota mechanism would be circumvented.
3123 */
3124 if (unlikely((target_dp->i_diflags & XFS_DIFLAG_PROJINHERIT) &&
3125 target_dp->i_projid != src_ip->i_projid)) {
3126 error = -EXDEV;
3127 goto out_trans_cancel;
3128 }
3129
3130 /* RENAME_EXCHANGE is unique from here on. */
3131 if (flags & RENAME_EXCHANGE)
3132 return xfs_cross_rename(tp, src_dp, src_name, src_ip,
3133 target_dp, target_name, target_ip,
3134 spaceres);
3135
3136 /*
3137 * Check for expected errors before we dirty the transaction
3138 * so we can return an error without a transaction abort.
3139 *
3140 * Extent count overflow check:
3141 *
3142 * From the perspective of src_dp, a rename operation is essentially a
3143 * directory entry remove operation. Hence the only place where we check
3144 * for extent count overflow for src_dp is in
3145 * xfs_bmap_del_extent_real(). xfs_bmap_del_extent_real() returns
3146 * -ENOSPC when it detects a possible extent count overflow and in
3147 * response, the higher layers of directory handling code do the
3148 * following:
3149 * 1. Data/Free blocks: XFS lets these blocks linger until a
3150 * future remove operation removes them.
3151 * 2. Dabtree blocks: XFS swaps the blocks with the last block in the
3152 * Leaf space and unmaps the last block.
3153 *
3154 * For target_dp, there are two cases depending on whether the
3155 * destination directory entry exists or not.
3156 *
3157 * When destination directory entry does not exist (i.e. target_ip ==
3158 * NULL), extent count overflow check is performed only when transaction
3159 * has a non-zero sized space reservation associated with it. With a
3160 * zero-sized space reservation, XFS allows a rename operation to
3161 * continue only when the directory has sufficient free space in its
3162 * data/leaf/free space blocks to hold the new entry.
3163 *
3164 * When destination directory entry exists (i.e. target_ip != NULL), all
3165 * we need to do is change the inode number associated with the already
3166 * existing entry. Hence there is no need to perform an extent count
3167 * overflow check.
3168 */
3169 if (target_ip == NULL) {
3170 /*
3171 * If there's no space reservation, check the entry will
3172 * fit before actually inserting it.
3173 */
3174 if (!spaceres) {
3175 error = xfs_dir_canenter(tp, target_dp, target_name);
3176 if (error)
3177 goto out_trans_cancel;
3178 } else {
3179 error = xfs_iext_count_may_overflow(target_dp,
3180 XFS_DATA_FORK,
3181 XFS_IEXT_DIR_MANIP_CNT(mp));
3182 if (error)
3183 goto out_trans_cancel;
3184 }
3185 } else {
3186 /*
3187 * If target exists and it's a directory, check that whether
3188 * it can be destroyed.
3189 */
3190 if (S_ISDIR(VFS_I(target_ip)->i_mode) &&
3191 (!xfs_dir_isempty(target_ip) ||
3192 (VFS_I(target_ip)->i_nlink > 2))) {
3193 error = -EEXIST;
3194 goto out_trans_cancel;
3195 }
3196 }
3197
3198 /*
3199 * Lock the AGI buffers we need to handle bumping the nlink of the
3200 * whiteout inode off the unlinked list and to handle dropping the
3201 * nlink of the target inode. Per locking order rules, do this in
3202 * increasing AG order and before directory block allocation tries to
3203 * grab AGFs because we grab AGIs before AGFs.
3204 *
3205 * The (vfs) caller must ensure that if src is a directory then
3206 * target_ip is either null or an empty directory.
3207 */
3208 for (i = 0; i < num_inodes && inodes[i] != NULL; i++) {
3209 if (inodes[i] == wip ||
3210 (inodes[i] == target_ip &&
3211 (VFS_I(target_ip)->i_nlink == 1 || src_is_directory))) {
3212 struct xfs_buf *bp;
3213 xfs_agnumber_t agno;
3214
3215 agno = XFS_INO_TO_AGNO(mp, inodes[i]->i_ino);
3216 error = xfs_read_agi(mp, tp, agno, &bp);
3217 if (error)
3218 goto out_trans_cancel;
3219 }
3220 }
3221
3222 /*
3223 * Directory entry creation below may acquire the AGF. Remove
3224 * the whiteout from the unlinked list first to preserve correct
3225 * AGI/AGF locking order. This dirties the transaction so failures
3226 * after this point will abort and log recovery will clean up the
3227 * mess.
3228 *
3229 * For whiteouts, we need to bump the link count on the whiteout
3230 * inode. After this point, we have a real link, clear the tmpfile
3231 * state flag from the inode so it doesn't accidentally get misused
3232 * in future.
3233 */
3234 if (wip) {
3235 struct xfs_perag *pag;
3236
3237 ASSERT(VFS_I(wip)->i_nlink == 0);
3238
3239 pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, wip->i_ino));
3240 error = xfs_iunlink_remove(tp, pag, wip);
3241 xfs_perag_put(pag);
3242 if (error)
3243 goto out_trans_cancel;
3244
3245 xfs_bumplink(tp, wip);
3246 VFS_I(wip)->i_state &= ~I_LINKABLE;
3247 }
3248
3249 /*
3250 * Set up the target.
3251 */
3252 if (target_ip == NULL) {
3253 /*
3254 * If target does not exist and the rename crosses
3255 * directories, adjust the target directory link count
3256 * to account for the ".." reference from the new entry.
3257 */
3258 error = xfs_dir_createname(tp, target_dp, target_name,
3259 src_ip->i_ino, spaceres);
3260 if (error)
3261 goto out_trans_cancel;
3262
3263 xfs_trans_ichgtime(tp, target_dp,
3264 XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
3265
3266 if (new_parent && src_is_directory) {
3267 xfs_bumplink(tp, target_dp);
3268 }
3269 } else { /* target_ip != NULL */
3270 /*
3271 * Link the source inode under the target name.
3272 * If the source inode is a directory and we are moving
3273 * it across directories, its ".." entry will be
3274 * inconsistent until we replace that down below.
3275 *
3276 * In case there is already an entry with the same
3277 * name at the destination directory, remove it first.
3278 */
3279 error = xfs_dir_replace(tp, target_dp, target_name,
3280 src_ip->i_ino, spaceres);
3281 if (error)
3282 goto out_trans_cancel;
3283
3284 xfs_trans_ichgtime(tp, target_dp,
3285 XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
3286
3287 /*
3288 * Decrement the link count on the target since the target
3289 * dir no longer points to it.
3290 */
3291 error = xfs_droplink(tp, target_ip);
3292 if (error)
3293 goto out_trans_cancel;
3294
3295 if (src_is_directory) {
3296 /*
3297 * Drop the link from the old "." entry.
3298 */
3299 error = xfs_droplink(tp, target_ip);
3300 if (error)
3301 goto out_trans_cancel;
3302 }
3303 } /* target_ip != NULL */
3304
3305 /*
3306 * Remove the source.
3307 */
3308 if (new_parent && src_is_directory) {
3309 /*
3310 * Rewrite the ".." entry to point to the new
3311 * directory.
3312 */
3313 error = xfs_dir_replace(tp, src_ip, &xfs_name_dotdot,
3314 target_dp->i_ino, spaceres);
3315 ASSERT(error != -EEXIST);
3316 if (error)
3317 goto out_trans_cancel;
3318 }
3319
3320 /*
3321 * We always want to hit the ctime on the source inode.
3322 *
3323 * This isn't strictly required by the standards since the source
3324 * inode isn't really being changed, but old unix file systems did
3325 * it and some incremental backup programs won't work without it.
3326 */
3327 xfs_trans_ichgtime(tp, src_ip, XFS_ICHGTIME_CHG);
3328 xfs_trans_log_inode(tp, src_ip, XFS_ILOG_CORE);
3329
3330 /*
3331 * Adjust the link count on src_dp. This is necessary when
3332 * renaming a directory, either within one parent when
3333 * the target existed, or across two parent directories.
3334 */
3335 if (src_is_directory && (new_parent || target_ip != NULL)) {
3336
3337 /*
3338 * Decrement link count on src_directory since the
3339 * entry that's moved no longer points to it.
3340 */
3341 error = xfs_droplink(tp, src_dp);
3342 if (error)
3343 goto out_trans_cancel;
3344 }
3345
3346 /*
3347 * For whiteouts, we only need to update the source dirent with the
3348 * inode number of the whiteout inode rather than removing it
3349 * altogether.
3350 */
3351 if (wip) {
3352 error = xfs_dir_replace(tp, src_dp, src_name, wip->i_ino,
3353 spaceres);
3354 } else {
3355 /*
3356 * NOTE: We don't need to check for extent count overflow here
3357 * because the dir remove name code will leave the dir block in
3358 * place if the extent count would overflow.
3359 */
3360 error = xfs_dir_removename(tp, src_dp, src_name, src_ip->i_ino,
3361 spaceres);
3362 }
3363
3364 if (error)
3365 goto out_trans_cancel;
3366
3367 xfs_trans_ichgtime(tp, src_dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
3368 xfs_trans_log_inode(tp, src_dp, XFS_ILOG_CORE);
3369 if (new_parent)
3370 xfs_trans_log_inode(tp, target_dp, XFS_ILOG_CORE);
3371
3372 error = xfs_finish_rename(tp);
3373 if (wip)
3374 xfs_irele(wip);
3375 return error;
3376
3377out_trans_cancel:
3378 xfs_trans_cancel(tp);
3379out_release_wip:
3380 if (wip)
3381 xfs_irele(wip);
3382 return error;
3383}
3384
3385static int
3386xfs_iflush(
3387 struct xfs_inode *ip,
3388 struct xfs_buf *bp)
3389{
3390 struct xfs_inode_log_item *iip = ip->i_itemp;
3391 struct xfs_dinode *dip;
3392 struct xfs_mount *mp = ip->i_mount;
3393 int error;
3394
3395 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
3396 ASSERT(xfs_iflags_test(ip, XFS_IFLUSHING));
3397 ASSERT(ip->i_df.if_format != XFS_DINODE_FMT_BTREE ||
3398 ip->i_df.if_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK));
3399 ASSERT(iip->ili_item.li_buf == bp);
3400
3401 dip = xfs_buf_offset(bp, ip->i_imap.im_boffset);
3402
3403 /*
3404 * We don't flush the inode if any of the following checks fail, but we
3405 * do still update the log item and attach to the backing buffer as if
3406 * the flush happened. This is a formality to facilitate predictable
3407 * error handling as the caller will shutdown and fail the buffer.
3408 */
3409 error = -EFSCORRUPTED;
3410 if (XFS_TEST_ERROR(dip->di_magic != cpu_to_be16(XFS_DINODE_MAGIC),
3411 mp, XFS_ERRTAG_IFLUSH_1)) {
3412 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3413 "%s: Bad inode %Lu magic number 0x%x, ptr "PTR_FMT,
3414 __func__, ip->i_ino, be16_to_cpu(dip->di_magic), dip);
3415 goto flush_out;
3416 }
3417 if (S_ISREG(VFS_I(ip)->i_mode)) {
3418 if (XFS_TEST_ERROR(
3419 ip->i_df.if_format != XFS_DINODE_FMT_EXTENTS &&
3420 ip->i_df.if_format != XFS_DINODE_FMT_BTREE,
3421 mp, XFS_ERRTAG_IFLUSH_3)) {
3422 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3423 "%s: Bad regular inode %Lu, ptr "PTR_FMT,
3424 __func__, ip->i_ino, ip);
3425 goto flush_out;
3426 }
3427 } else if (S_ISDIR(VFS_I(ip)->i_mode)) {
3428 if (XFS_TEST_ERROR(
3429 ip->i_df.if_format != XFS_DINODE_FMT_EXTENTS &&
3430 ip->i_df.if_format != XFS_DINODE_FMT_BTREE &&
3431 ip->i_df.if_format != XFS_DINODE_FMT_LOCAL,
3432 mp, XFS_ERRTAG_IFLUSH_4)) {
3433 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3434 "%s: Bad directory inode %Lu, ptr "PTR_FMT,
3435 __func__, ip->i_ino, ip);
3436 goto flush_out;
3437 }
3438 }
3439 if (XFS_TEST_ERROR(ip->i_df.if_nextents + xfs_ifork_nextents(ip->i_afp) >
3440 ip->i_nblocks, mp, XFS_ERRTAG_IFLUSH_5)) {
3441 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3442 "%s: detected corrupt incore inode %Lu, "
3443 "total extents = %d, nblocks = %Ld, ptr "PTR_FMT,
3444 __func__, ip->i_ino,
3445 ip->i_df.if_nextents + xfs_ifork_nextents(ip->i_afp),
3446 ip->i_nblocks, ip);
3447 goto flush_out;
3448 }
3449 if (XFS_TEST_ERROR(ip->i_forkoff > mp->m_sb.sb_inodesize,
3450 mp, XFS_ERRTAG_IFLUSH_6)) {
3451 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3452 "%s: bad inode %Lu, forkoff 0x%x, ptr "PTR_FMT,
3453 __func__, ip->i_ino, ip->i_forkoff, ip);
3454 goto flush_out;
3455 }
3456
3457 /*
3458 * Inode item log recovery for v2 inodes are dependent on the flushiter
3459 * count for correct sequencing. We bump the flush iteration count so
3460 * we can detect flushes which postdate a log record during recovery.
3461 * This is redundant as we now log every change and hence this can't
3462 * happen but we need to still do it to ensure backwards compatibility
3463 * with old kernels that predate logging all inode changes.
3464 */
3465 if (!xfs_sb_version_has_v3inode(&mp->m_sb))
3466 ip->i_flushiter++;
3467
3468 /*
3469 * If there are inline format data / attr forks attached to this inode,
3470 * make sure they are not corrupt.
3471 */
3472 if (ip->i_df.if_format == XFS_DINODE_FMT_LOCAL &&
3473 xfs_ifork_verify_local_data(ip))
3474 goto flush_out;
3475 if (ip->i_afp && ip->i_afp->if_format == XFS_DINODE_FMT_LOCAL &&
3476 xfs_ifork_verify_local_attr(ip))
3477 goto flush_out;
3478
3479 /*
3480 * Copy the dirty parts of the inode into the on-disk inode. We always
3481 * copy out the core of the inode, because if the inode is dirty at all
3482 * the core must be.
3483 */
3484 xfs_inode_to_disk(ip, dip, iip->ili_item.li_lsn);
3485
3486 /* Wrap, we never let the log put out DI_MAX_FLUSH */
3487 if (!xfs_sb_version_has_v3inode(&mp->m_sb)) {
3488 if (ip->i_flushiter == DI_MAX_FLUSH)
3489 ip->i_flushiter = 0;
3490 }
3491
3492 xfs_iflush_fork(ip, dip, iip, XFS_DATA_FORK);
3493 if (XFS_IFORK_Q(ip))
3494 xfs_iflush_fork(ip, dip, iip, XFS_ATTR_FORK);
3495
3496 /*
3497 * We've recorded everything logged in the inode, so we'd like to clear
3498 * the ili_fields bits so we don't log and flush things unnecessarily.
3499 * However, we can't stop logging all this information until the data
3500 * we've copied into the disk buffer is written to disk. If we did we
3501 * might overwrite the copy of the inode in the log with all the data
3502 * after re-logging only part of it, and in the face of a crash we
3503 * wouldn't have all the data we need to recover.
3504 *
3505 * What we do is move the bits to the ili_last_fields field. When
3506 * logging the inode, these bits are moved back to the ili_fields field.
3507 * In the xfs_buf_inode_iodone() routine we clear ili_last_fields, since
3508 * we know that the information those bits represent is permanently on
3509 * disk. As long as the flush completes before the inode is logged
3510 * again, then both ili_fields and ili_last_fields will be cleared.
3511 */
3512 error = 0;
3513flush_out:
3514 spin_lock(&iip->ili_lock);
3515 iip->ili_last_fields = iip->ili_fields;
3516 iip->ili_fields = 0;
3517 iip->ili_fsync_fields = 0;
3518 spin_unlock(&iip->ili_lock);
3519
3520 /*
3521 * Store the current LSN of the inode so that we can tell whether the
3522 * item has moved in the AIL from xfs_buf_inode_iodone().
3523 */
3524 xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn,
3525 &iip->ili_item.li_lsn);
3526
3527 /* generate the checksum. */
3528 xfs_dinode_calc_crc(mp, dip);
3529 return error;
3530}
3531
3532/*
3533 * Non-blocking flush of dirty inode metadata into the backing buffer.
3534 *
3535 * The caller must have a reference to the inode and hold the cluster buffer
3536 * locked. The function will walk across all the inodes on the cluster buffer it
3537 * can find and lock without blocking, and flush them to the cluster buffer.
3538 *
3539 * On successful flushing of at least one inode, the caller must write out the
3540 * buffer and release it. If no inodes are flushed, -EAGAIN will be returned and
3541 * the caller needs to release the buffer. On failure, the filesystem will be
3542 * shut down, the buffer will have been unlocked and released, and EFSCORRUPTED
3543 * will be returned.
3544 */
3545int
3546xfs_iflush_cluster(
3547 struct xfs_buf *bp)
3548{
3549 struct xfs_mount *mp = bp->b_mount;
3550 struct xfs_log_item *lip, *n;
3551 struct xfs_inode *ip;
3552 struct xfs_inode_log_item *iip;
3553 int clcount = 0;
3554 int error = 0;
3555
3556 /*
3557 * We must use the safe variant here as on shutdown xfs_iflush_abort()
3558 * can remove itself from the list.
3559 */
3560 list_for_each_entry_safe(lip, n, &bp->b_li_list, li_bio_list) {
3561 iip = (struct xfs_inode_log_item *)lip;
3562 ip = iip->ili_inode;
3563
3564 /*
3565 * Quick and dirty check to avoid locks if possible.
3566 */
3567 if (__xfs_iflags_test(ip, XFS_IRECLAIM | XFS_IFLUSHING))
3568 continue;
3569 if (xfs_ipincount(ip))
3570 continue;
3571
3572 /*
3573 * The inode is still attached to the buffer, which means it is
3574 * dirty but reclaim might try to grab it. Check carefully for
3575 * that, and grab the ilock while still holding the i_flags_lock
3576 * to guarantee reclaim will not be able to reclaim this inode
3577 * once we drop the i_flags_lock.
3578 */
3579 spin_lock(&ip->i_flags_lock);
3580 ASSERT(!__xfs_iflags_test(ip, XFS_ISTALE));
3581 if (__xfs_iflags_test(ip, XFS_IRECLAIM | XFS_IFLUSHING)) {
3582 spin_unlock(&ip->i_flags_lock);
3583 continue;
3584 }
3585
3586 /*
3587 * ILOCK will pin the inode against reclaim and prevent
3588 * concurrent transactions modifying the inode while we are
3589 * flushing the inode. If we get the lock, set the flushing
3590 * state before we drop the i_flags_lock.
3591 */
3592 if (!xfs_ilock_nowait(ip, XFS_ILOCK_SHARED)) {
3593 spin_unlock(&ip->i_flags_lock);
3594 continue;
3595 }
3596 __xfs_iflags_set(ip, XFS_IFLUSHING);
3597 spin_unlock(&ip->i_flags_lock);
3598
3599 /*
3600 * Abort flushing this inode if we are shut down because the
3601 * inode may not currently be in the AIL. This can occur when
3602 * log I/O failure unpins the inode without inserting into the
3603 * AIL, leaving a dirty/unpinned inode attached to the buffer
3604 * that otherwise looks like it should be flushed.
3605 */
3606 if (XFS_FORCED_SHUTDOWN(mp)) {
3607 xfs_iunpin_wait(ip);
3608 xfs_iflush_abort(ip);
3609 xfs_iunlock(ip, XFS_ILOCK_SHARED);
3610 error = -EIO;
3611 continue;
3612 }
3613
3614 /* don't block waiting on a log force to unpin dirty inodes */
3615 if (xfs_ipincount(ip)) {
3616 xfs_iflags_clear(ip, XFS_IFLUSHING);
3617 xfs_iunlock(ip, XFS_ILOCK_SHARED);
3618 continue;
3619 }
3620
3621 if (!xfs_inode_clean(ip))
3622 error = xfs_iflush(ip, bp);
3623 else
3624 xfs_iflags_clear(ip, XFS_IFLUSHING);
3625 xfs_iunlock(ip, XFS_ILOCK_SHARED);
3626 if (error)
3627 break;
3628 clcount++;
3629 }
3630
3631 if (error) {
3632 bp->b_flags |= XBF_ASYNC;
3633 xfs_buf_ioend_fail(bp);
3634 xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
3635 return error;
3636 }
3637
3638 if (!clcount)
3639 return -EAGAIN;
3640
3641 XFS_STATS_INC(mp, xs_icluster_flushcnt);
3642 XFS_STATS_ADD(mp, xs_icluster_flushinode, clcount);
3643 return 0;
3644
3645}
3646
3647/* Release an inode. */
3648void
3649xfs_irele(
3650 struct xfs_inode *ip)
3651{
3652 trace_xfs_irele(ip, _RET_IP_);
3653 iput(VFS_I(ip));
3654}
3655
3656/*
3657 * Ensure all commited transactions touching the inode are written to the log.
3658 */
3659int
3660xfs_log_force_inode(
3661 struct xfs_inode *ip)
3662{
3663 xfs_csn_t seq = 0;
3664
3665 xfs_ilock(ip, XFS_ILOCK_SHARED);
3666 if (xfs_ipincount(ip))
3667 seq = ip->i_itemp->ili_commit_seq;
3668 xfs_iunlock(ip, XFS_ILOCK_SHARED);
3669
3670 if (!seq)
3671 return 0;
3672 return xfs_log_force_seq(ip->i_mount, seq, XFS_LOG_SYNC, NULL);
3673}
3674
3675/*
3676 * Grab the exclusive iolock for a data copy from src to dest, making sure to
3677 * abide vfs locking order (lowest pointer value goes first) and breaking the
3678 * layout leases before proceeding. The loop is needed because we cannot call
3679 * the blocking break_layout() with the iolocks held, and therefore have to
3680 * back out both locks.
3681 */
3682static int
3683xfs_iolock_two_inodes_and_break_layout(
3684 struct inode *src,
3685 struct inode *dest)
3686{
3687 int error;
3688
3689 if (src > dest)
3690 swap(src, dest);
3691
3692retry:
3693 /* Wait to break both inodes' layouts before we start locking. */
3694 error = break_layout(src, true);
3695 if (error)
3696 return error;
3697 if (src != dest) {
3698 error = break_layout(dest, true);
3699 if (error)
3700 return error;
3701 }
3702
3703 /* Lock one inode and make sure nobody got in and leased it. */
3704 inode_lock(src);
3705 error = break_layout(src, false);
3706 if (error) {
3707 inode_unlock(src);
3708 if (error == -EWOULDBLOCK)
3709 goto retry;
3710 return error;
3711 }
3712
3713 if (src == dest)
3714 return 0;
3715
3716 /* Lock the other inode and make sure nobody got in and leased it. */
3717 inode_lock_nested(dest, I_MUTEX_NONDIR2);
3718 error = break_layout(dest, false);
3719 if (error) {
3720 inode_unlock(src);
3721 inode_unlock(dest);
3722 if (error == -EWOULDBLOCK)
3723 goto retry;
3724 return error;
3725 }
3726
3727 return 0;
3728}
3729
3730/*
3731 * Lock two inodes so that userspace cannot initiate I/O via file syscalls or
3732 * mmap activity.
3733 */
3734int
3735xfs_ilock2_io_mmap(
3736 struct xfs_inode *ip1,
3737 struct xfs_inode *ip2)
3738{
3739 int ret;
3740
3741 ret = xfs_iolock_two_inodes_and_break_layout(VFS_I(ip1), VFS_I(ip2));
3742 if (ret)
3743 return ret;
3744 if (ip1 == ip2)
3745 xfs_ilock(ip1, XFS_MMAPLOCK_EXCL);
3746 else
3747 xfs_lock_two_inodes(ip1, XFS_MMAPLOCK_EXCL,
3748 ip2, XFS_MMAPLOCK_EXCL);
3749 return 0;
3750}
3751
3752/* Unlock both inodes to allow IO and mmap activity. */
3753void
3754xfs_iunlock2_io_mmap(
3755 struct xfs_inode *ip1,
3756 struct xfs_inode *ip2)
3757{
3758 bool same_inode = (ip1 == ip2);
3759
3760 xfs_iunlock(ip2, XFS_MMAPLOCK_EXCL);
3761 if (!same_inode)
3762 xfs_iunlock(ip1, XFS_MMAPLOCK_EXCL);
3763 inode_unlock(VFS_I(ip2));
3764 if (!same_inode)
3765 inode_unlock(VFS_I(ip1));
3766}