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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
41struct kmem_cache *xfs_inode_cache;
42
43/*
44 * Used in xfs_itruncate_extents(). This is the maximum number of extents
45 * freed from a file in a single transaction.
46 */
47#define XFS_ITRUNC_MAX_EXTENTS 2
48
49STATIC int xfs_iunlink(struct xfs_trans *, struct xfs_inode *);
50STATIC int xfs_iunlink_remove(struct xfs_trans *tp, struct xfs_perag *pag,
51 struct xfs_inode *);
52
53/*
54 * helper function to extract extent size hint from inode
55 */
56xfs_extlen_t
57xfs_get_extsz_hint(
58 struct xfs_inode *ip)
59{
60 /*
61 * No point in aligning allocations if we need to COW to actually
62 * write to them.
63 */
64 if (xfs_is_always_cow_inode(ip))
65 return 0;
66 if ((ip->i_diflags & XFS_DIFLAG_EXTSIZE) && ip->i_extsize)
67 return ip->i_extsize;
68 if (XFS_IS_REALTIME_INODE(ip))
69 return ip->i_mount->m_sb.sb_rextsize;
70 return 0;
71}
72
73/*
74 * Helper function to extract CoW extent size hint from inode.
75 * Between the extent size hint and the CoW extent size hint, we
76 * return the greater of the two. If the value is zero (automatic),
77 * use the default size.
78 */
79xfs_extlen_t
80xfs_get_cowextsz_hint(
81 struct xfs_inode *ip)
82{
83 xfs_extlen_t a, b;
84
85 a = 0;
86 if (ip->i_diflags2 & XFS_DIFLAG2_COWEXTSIZE)
87 a = ip->i_cowextsize;
88 b = xfs_get_extsz_hint(ip);
89
90 a = max(a, b);
91 if (a == 0)
92 return XFS_DEFAULT_COWEXTSZ_HINT;
93 return a;
94}
95
96/*
97 * These two are wrapper routines around the xfs_ilock() routine used to
98 * centralize some grungy code. They are used in places that wish to lock the
99 * inode solely for reading the extents. The reason these places can't just
100 * call xfs_ilock(ip, XFS_ILOCK_SHARED) is that the inode lock also guards to
101 * bringing in of the extents from disk for a file in b-tree format. If the
102 * inode is in b-tree format, then we need to lock the inode exclusively until
103 * the extents are read in. Locking it exclusively all the time would limit
104 * our parallelism unnecessarily, though. What we do instead is check to see
105 * if the extents have been read in yet, and only lock the inode exclusively
106 * if they have not.
107 *
108 * The functions return a value which should be given to the corresponding
109 * xfs_iunlock() call.
110 */
111uint
112xfs_ilock_data_map_shared(
113 struct xfs_inode *ip)
114{
115 uint lock_mode = XFS_ILOCK_SHARED;
116
117 if (xfs_need_iread_extents(&ip->i_df))
118 lock_mode = XFS_ILOCK_EXCL;
119 xfs_ilock(ip, lock_mode);
120 return lock_mode;
121}
122
123uint
124xfs_ilock_attr_map_shared(
125 struct xfs_inode *ip)
126{
127 uint lock_mode = XFS_ILOCK_SHARED;
128
129 if (xfs_inode_has_attr_fork(ip) && xfs_need_iread_extents(&ip->i_af))
130 lock_mode = XFS_ILOCK_EXCL;
131 xfs_ilock(ip, lock_mode);
132 return lock_mode;
133}
134
135/*
136 * You can't set both SHARED and EXCL for the same lock,
137 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_MMAPLOCK_SHARED,
138 * XFS_MMAPLOCK_EXCL, XFS_ILOCK_SHARED, XFS_ILOCK_EXCL are valid values
139 * to set in lock_flags.
140 */
141static inline void
142xfs_lock_flags_assert(
143 uint lock_flags)
144{
145 ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
146 (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
147 ASSERT((lock_flags & (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)) !=
148 (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL));
149 ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
150 (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
151 ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0);
152 ASSERT(lock_flags != 0);
153}
154
155/*
156 * In addition to i_rwsem in the VFS inode, the xfs inode contains 2
157 * multi-reader locks: invalidate_lock and the i_lock. This routine allows
158 * various combinations of the locks to be obtained.
159 *
160 * The 3 locks should always be ordered so that the IO lock is obtained first,
161 * the mmap lock second and the ilock last in order to prevent deadlock.
162 *
163 * Basic locking order:
164 *
165 * i_rwsem -> invalidate_lock -> page_lock -> i_ilock
166 *
167 * mmap_lock locking order:
168 *
169 * i_rwsem -> page lock -> mmap_lock
170 * mmap_lock -> invalidate_lock -> page_lock
171 *
172 * The difference in mmap_lock locking order mean that we cannot hold the
173 * invalidate_lock over syscall based read(2)/write(2) based IO. These IO paths
174 * can fault in pages during copy in/out (for buffered IO) or require the
175 * mmap_lock in get_user_pages() to map the user pages into the kernel address
176 * space for direct IO. Similarly the i_rwsem cannot be taken inside a page
177 * fault because page faults already hold the mmap_lock.
178 *
179 * Hence to serialise fully against both syscall and mmap based IO, we need to
180 * take both the i_rwsem and the invalidate_lock. These locks should *only* be
181 * both taken in places where we need to invalidate the page cache in a race
182 * free manner (e.g. truncate, hole punch and other extent manipulation
183 * functions).
184 */
185void
186xfs_ilock(
187 xfs_inode_t *ip,
188 uint lock_flags)
189{
190 trace_xfs_ilock(ip, lock_flags, _RET_IP_);
191
192 xfs_lock_flags_assert(lock_flags);
193
194 if (lock_flags & XFS_IOLOCK_EXCL) {
195 down_write_nested(&VFS_I(ip)->i_rwsem,
196 XFS_IOLOCK_DEP(lock_flags));
197 } else if (lock_flags & XFS_IOLOCK_SHARED) {
198 down_read_nested(&VFS_I(ip)->i_rwsem,
199 XFS_IOLOCK_DEP(lock_flags));
200 }
201
202 if (lock_flags & XFS_MMAPLOCK_EXCL) {
203 down_write_nested(&VFS_I(ip)->i_mapping->invalidate_lock,
204 XFS_MMAPLOCK_DEP(lock_flags));
205 } else if (lock_flags & XFS_MMAPLOCK_SHARED) {
206 down_read_nested(&VFS_I(ip)->i_mapping->invalidate_lock,
207 XFS_MMAPLOCK_DEP(lock_flags));
208 }
209
210 if (lock_flags & XFS_ILOCK_EXCL)
211 mrupdate_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
212 else if (lock_flags & XFS_ILOCK_SHARED)
213 mraccess_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
214}
215
216/*
217 * This is just like xfs_ilock(), except that the caller
218 * is guaranteed not to sleep. It returns 1 if it gets
219 * the requested locks and 0 otherwise. If the IO lock is
220 * obtained but the inode lock cannot be, then the IO lock
221 * is dropped before returning.
222 *
223 * ip -- the inode being locked
224 * lock_flags -- this parameter indicates the inode's locks to be
225 * to be locked. See the comment for xfs_ilock() for a list
226 * of valid values.
227 */
228int
229xfs_ilock_nowait(
230 xfs_inode_t *ip,
231 uint lock_flags)
232{
233 trace_xfs_ilock_nowait(ip, lock_flags, _RET_IP_);
234
235 xfs_lock_flags_assert(lock_flags);
236
237 if (lock_flags & XFS_IOLOCK_EXCL) {
238 if (!down_write_trylock(&VFS_I(ip)->i_rwsem))
239 goto out;
240 } else if (lock_flags & XFS_IOLOCK_SHARED) {
241 if (!down_read_trylock(&VFS_I(ip)->i_rwsem))
242 goto out;
243 }
244
245 if (lock_flags & XFS_MMAPLOCK_EXCL) {
246 if (!down_write_trylock(&VFS_I(ip)->i_mapping->invalidate_lock))
247 goto out_undo_iolock;
248 } else if (lock_flags & XFS_MMAPLOCK_SHARED) {
249 if (!down_read_trylock(&VFS_I(ip)->i_mapping->invalidate_lock))
250 goto out_undo_iolock;
251 }
252
253 if (lock_flags & XFS_ILOCK_EXCL) {
254 if (!mrtryupdate(&ip->i_lock))
255 goto out_undo_mmaplock;
256 } else if (lock_flags & XFS_ILOCK_SHARED) {
257 if (!mrtryaccess(&ip->i_lock))
258 goto out_undo_mmaplock;
259 }
260 return 1;
261
262out_undo_mmaplock:
263 if (lock_flags & XFS_MMAPLOCK_EXCL)
264 up_write(&VFS_I(ip)->i_mapping->invalidate_lock);
265 else if (lock_flags & XFS_MMAPLOCK_SHARED)
266 up_read(&VFS_I(ip)->i_mapping->invalidate_lock);
267out_undo_iolock:
268 if (lock_flags & XFS_IOLOCK_EXCL)
269 up_write(&VFS_I(ip)->i_rwsem);
270 else if (lock_flags & XFS_IOLOCK_SHARED)
271 up_read(&VFS_I(ip)->i_rwsem);
272out:
273 return 0;
274}
275
276/*
277 * xfs_iunlock() is used to drop the inode locks acquired with
278 * xfs_ilock() and xfs_ilock_nowait(). The caller must pass
279 * in the flags given to xfs_ilock() or xfs_ilock_nowait() so
280 * that we know which locks to drop.
281 *
282 * ip -- the inode being unlocked
283 * lock_flags -- this parameter indicates the inode's locks to be
284 * to be unlocked. See the comment for xfs_ilock() for a list
285 * of valid values for this parameter.
286 *
287 */
288void
289xfs_iunlock(
290 xfs_inode_t *ip,
291 uint lock_flags)
292{
293 xfs_lock_flags_assert(lock_flags);
294
295 if (lock_flags & XFS_IOLOCK_EXCL)
296 up_write(&VFS_I(ip)->i_rwsem);
297 else if (lock_flags & XFS_IOLOCK_SHARED)
298 up_read(&VFS_I(ip)->i_rwsem);
299
300 if (lock_flags & XFS_MMAPLOCK_EXCL)
301 up_write(&VFS_I(ip)->i_mapping->invalidate_lock);
302 else if (lock_flags & XFS_MMAPLOCK_SHARED)
303 up_read(&VFS_I(ip)->i_mapping->invalidate_lock);
304
305 if (lock_flags & XFS_ILOCK_EXCL)
306 mrunlock_excl(&ip->i_lock);
307 else if (lock_flags & XFS_ILOCK_SHARED)
308 mrunlock_shared(&ip->i_lock);
309
310 trace_xfs_iunlock(ip, lock_flags, _RET_IP_);
311}
312
313/*
314 * give up write locks. the i/o lock cannot be held nested
315 * if it is being demoted.
316 */
317void
318xfs_ilock_demote(
319 xfs_inode_t *ip,
320 uint lock_flags)
321{
322 ASSERT(lock_flags & (XFS_IOLOCK_EXCL|XFS_MMAPLOCK_EXCL|XFS_ILOCK_EXCL));
323 ASSERT((lock_flags &
324 ~(XFS_IOLOCK_EXCL|XFS_MMAPLOCK_EXCL|XFS_ILOCK_EXCL)) == 0);
325
326 if (lock_flags & XFS_ILOCK_EXCL)
327 mrdemote(&ip->i_lock);
328 if (lock_flags & XFS_MMAPLOCK_EXCL)
329 downgrade_write(&VFS_I(ip)->i_mapping->invalidate_lock);
330 if (lock_flags & XFS_IOLOCK_EXCL)
331 downgrade_write(&VFS_I(ip)->i_rwsem);
332
333 trace_xfs_ilock_demote(ip, lock_flags, _RET_IP_);
334}
335
336#if defined(DEBUG) || defined(XFS_WARN)
337static inline bool
338__xfs_rwsem_islocked(
339 struct rw_semaphore *rwsem,
340 bool shared)
341{
342 if (!debug_locks)
343 return rwsem_is_locked(rwsem);
344
345 if (!shared)
346 return lockdep_is_held_type(rwsem, 0);
347
348 /*
349 * We are checking that the lock is held at least in shared
350 * mode but don't care that it might be held exclusively
351 * (i.e. shared | excl). Hence we check if the lock is held
352 * in any mode rather than an explicit shared mode.
353 */
354 return lockdep_is_held_type(rwsem, -1);
355}
356
357bool
358xfs_isilocked(
359 struct xfs_inode *ip,
360 uint lock_flags)
361{
362 if (lock_flags & (XFS_ILOCK_EXCL|XFS_ILOCK_SHARED)) {
363 if (!(lock_flags & XFS_ILOCK_SHARED))
364 return !!ip->i_lock.mr_writer;
365 return rwsem_is_locked(&ip->i_lock.mr_lock);
366 }
367
368 if (lock_flags & (XFS_MMAPLOCK_EXCL|XFS_MMAPLOCK_SHARED)) {
369 return __xfs_rwsem_islocked(&VFS_I(ip)->i_mapping->invalidate_lock,
370 (lock_flags & XFS_MMAPLOCK_SHARED));
371 }
372
373 if (lock_flags & (XFS_IOLOCK_EXCL | XFS_IOLOCK_SHARED)) {
374 return __xfs_rwsem_islocked(&VFS_I(ip)->i_rwsem,
375 (lock_flags & XFS_IOLOCK_SHARED));
376 }
377
378 ASSERT(0);
379 return false;
380}
381#endif
382
383/*
384 * xfs_lockdep_subclass_ok() is only used in an ASSERT, so is only called when
385 * DEBUG or XFS_WARN is set. And MAX_LOCKDEP_SUBCLASSES is then only defined
386 * when CONFIG_LOCKDEP is set. Hence the complex define below to avoid build
387 * errors and warnings.
388 */
389#if (defined(DEBUG) || defined(XFS_WARN)) && defined(CONFIG_LOCKDEP)
390static bool
391xfs_lockdep_subclass_ok(
392 int subclass)
393{
394 return subclass < MAX_LOCKDEP_SUBCLASSES;
395}
396#else
397#define xfs_lockdep_subclass_ok(subclass) (true)
398#endif
399
400/*
401 * Bump the subclass so xfs_lock_inodes() acquires each lock with a different
402 * value. This can be called for any type of inode lock combination, including
403 * parent locking. Care must be taken to ensure we don't overrun the subclass
404 * storage fields in the class mask we build.
405 */
406static inline uint
407xfs_lock_inumorder(
408 uint lock_mode,
409 uint subclass)
410{
411 uint class = 0;
412
413 ASSERT(!(lock_mode & (XFS_ILOCK_PARENT | XFS_ILOCK_RTBITMAP |
414 XFS_ILOCK_RTSUM)));
415 ASSERT(xfs_lockdep_subclass_ok(subclass));
416
417 if (lock_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)) {
418 ASSERT(subclass <= XFS_IOLOCK_MAX_SUBCLASS);
419 class += subclass << XFS_IOLOCK_SHIFT;
420 }
421
422 if (lock_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) {
423 ASSERT(subclass <= XFS_MMAPLOCK_MAX_SUBCLASS);
424 class += subclass << XFS_MMAPLOCK_SHIFT;
425 }
426
427 if (lock_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)) {
428 ASSERT(subclass <= XFS_ILOCK_MAX_SUBCLASS);
429 class += subclass << XFS_ILOCK_SHIFT;
430 }
431
432 return (lock_mode & ~XFS_LOCK_SUBCLASS_MASK) | class;
433}
434
435/*
436 * The following routine will lock n inodes in exclusive mode. We assume the
437 * caller calls us with the inodes in i_ino order.
438 *
439 * We need to detect deadlock where an inode that we lock is in the AIL and we
440 * start waiting for another inode that is locked by a thread in a long running
441 * transaction (such as truncate). This can result in deadlock since the long
442 * running trans might need to wait for the inode we just locked in order to
443 * push the tail and free space in the log.
444 *
445 * xfs_lock_inodes() can only be used to lock one type of lock at a time -
446 * the iolock, the mmaplock or the ilock, but not more than one at a time. If we
447 * lock more than one at a time, lockdep will report false positives saying we
448 * have violated locking orders.
449 */
450static void
451xfs_lock_inodes(
452 struct xfs_inode **ips,
453 int inodes,
454 uint lock_mode)
455{
456 int attempts = 0;
457 uint i;
458 int j;
459 bool try_lock;
460 struct xfs_log_item *lp;
461
462 /*
463 * Currently supports between 2 and 5 inodes with exclusive locking. We
464 * support an arbitrary depth of locking here, but absolute limits on
465 * inodes depend on the type of locking and the limits placed by
466 * lockdep annotations in xfs_lock_inumorder. These are all checked by
467 * the asserts.
468 */
469 ASSERT(ips && inodes >= 2 && inodes <= 5);
470 ASSERT(lock_mode & (XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL |
471 XFS_ILOCK_EXCL));
472 ASSERT(!(lock_mode & (XFS_IOLOCK_SHARED | XFS_MMAPLOCK_SHARED |
473 XFS_ILOCK_SHARED)));
474 ASSERT(!(lock_mode & XFS_MMAPLOCK_EXCL) ||
475 inodes <= XFS_MMAPLOCK_MAX_SUBCLASS + 1);
476 ASSERT(!(lock_mode & XFS_ILOCK_EXCL) ||
477 inodes <= XFS_ILOCK_MAX_SUBCLASS + 1);
478
479 if (lock_mode & XFS_IOLOCK_EXCL) {
480 ASSERT(!(lock_mode & (XFS_MMAPLOCK_EXCL | XFS_ILOCK_EXCL)));
481 } else if (lock_mode & XFS_MMAPLOCK_EXCL)
482 ASSERT(!(lock_mode & XFS_ILOCK_EXCL));
483
484again:
485 try_lock = false;
486 i = 0;
487 for (; i < inodes; i++) {
488 ASSERT(ips[i]);
489
490 if (i && (ips[i] == ips[i - 1])) /* Already locked */
491 continue;
492
493 /*
494 * If try_lock is not set yet, make sure all locked inodes are
495 * not in the AIL. If any are, set try_lock to be used later.
496 */
497 if (!try_lock) {
498 for (j = (i - 1); j >= 0 && !try_lock; j--) {
499 lp = &ips[j]->i_itemp->ili_item;
500 if (lp && test_bit(XFS_LI_IN_AIL, &lp->li_flags))
501 try_lock = true;
502 }
503 }
504
505 /*
506 * If any of the previous locks we have locked is in the AIL,
507 * we must TRY to get the second and subsequent locks. If
508 * we can't get any, we must release all we have
509 * and try again.
510 */
511 if (!try_lock) {
512 xfs_ilock(ips[i], xfs_lock_inumorder(lock_mode, i));
513 continue;
514 }
515
516 /* try_lock means we have an inode locked that is in the AIL. */
517 ASSERT(i != 0);
518 if (xfs_ilock_nowait(ips[i], xfs_lock_inumorder(lock_mode, i)))
519 continue;
520
521 /*
522 * Unlock all previous guys and try again. xfs_iunlock will try
523 * to push the tail if the inode is in the AIL.
524 */
525 attempts++;
526 for (j = i - 1; j >= 0; j--) {
527 /*
528 * Check to see if we've already unlocked this one. Not
529 * the first one going back, and the inode ptr is the
530 * same.
531 */
532 if (j != (i - 1) && ips[j] == ips[j + 1])
533 continue;
534
535 xfs_iunlock(ips[j], lock_mode);
536 }
537
538 if ((attempts % 5) == 0) {
539 delay(1); /* Don't just spin the CPU */
540 }
541 goto again;
542 }
543}
544
545/*
546 * xfs_lock_two_inodes() can only be used to lock ilock. The iolock and
547 * mmaplock must be double-locked separately since we use i_rwsem and
548 * invalidate_lock for that. We now support taking one lock EXCL and the
549 * other SHARED.
550 */
551void
552xfs_lock_two_inodes(
553 struct xfs_inode *ip0,
554 uint ip0_mode,
555 struct xfs_inode *ip1,
556 uint ip1_mode)
557{
558 int attempts = 0;
559 struct xfs_log_item *lp;
560
561 ASSERT(hweight32(ip0_mode) == 1);
562 ASSERT(hweight32(ip1_mode) == 1);
563 ASSERT(!(ip0_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)));
564 ASSERT(!(ip1_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)));
565 ASSERT(!(ip0_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)));
566 ASSERT(!(ip1_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)));
567 ASSERT(ip0->i_ino != ip1->i_ino);
568
569 if (ip0->i_ino > ip1->i_ino) {
570 swap(ip0, ip1);
571 swap(ip0_mode, ip1_mode);
572 }
573
574 again:
575 xfs_ilock(ip0, xfs_lock_inumorder(ip0_mode, 0));
576
577 /*
578 * If the first lock we have locked is in the AIL, we must TRY to get
579 * the second lock. If we can't get it, we must release the first one
580 * and try again.
581 */
582 lp = &ip0->i_itemp->ili_item;
583 if (lp && test_bit(XFS_LI_IN_AIL, &lp->li_flags)) {
584 if (!xfs_ilock_nowait(ip1, xfs_lock_inumorder(ip1_mode, 1))) {
585 xfs_iunlock(ip0, ip0_mode);
586 if ((++attempts % 5) == 0)
587 delay(1); /* Don't just spin the CPU */
588 goto again;
589 }
590 } else {
591 xfs_ilock(ip1, xfs_lock_inumorder(ip1_mode, 1));
592 }
593}
594
595uint
596xfs_ip2xflags(
597 struct xfs_inode *ip)
598{
599 uint flags = 0;
600
601 if (ip->i_diflags & XFS_DIFLAG_ANY) {
602 if (ip->i_diflags & XFS_DIFLAG_REALTIME)
603 flags |= FS_XFLAG_REALTIME;
604 if (ip->i_diflags & XFS_DIFLAG_PREALLOC)
605 flags |= FS_XFLAG_PREALLOC;
606 if (ip->i_diflags & XFS_DIFLAG_IMMUTABLE)
607 flags |= FS_XFLAG_IMMUTABLE;
608 if (ip->i_diflags & XFS_DIFLAG_APPEND)
609 flags |= FS_XFLAG_APPEND;
610 if (ip->i_diflags & XFS_DIFLAG_SYNC)
611 flags |= FS_XFLAG_SYNC;
612 if (ip->i_diflags & XFS_DIFLAG_NOATIME)
613 flags |= FS_XFLAG_NOATIME;
614 if (ip->i_diflags & XFS_DIFLAG_NODUMP)
615 flags |= FS_XFLAG_NODUMP;
616 if (ip->i_diflags & XFS_DIFLAG_RTINHERIT)
617 flags |= FS_XFLAG_RTINHERIT;
618 if (ip->i_diflags & XFS_DIFLAG_PROJINHERIT)
619 flags |= FS_XFLAG_PROJINHERIT;
620 if (ip->i_diflags & XFS_DIFLAG_NOSYMLINKS)
621 flags |= FS_XFLAG_NOSYMLINKS;
622 if (ip->i_diflags & XFS_DIFLAG_EXTSIZE)
623 flags |= FS_XFLAG_EXTSIZE;
624 if (ip->i_diflags & XFS_DIFLAG_EXTSZINHERIT)
625 flags |= FS_XFLAG_EXTSZINHERIT;
626 if (ip->i_diflags & XFS_DIFLAG_NODEFRAG)
627 flags |= FS_XFLAG_NODEFRAG;
628 if (ip->i_diflags & XFS_DIFLAG_FILESTREAM)
629 flags |= FS_XFLAG_FILESTREAM;
630 }
631
632 if (ip->i_diflags2 & XFS_DIFLAG2_ANY) {
633 if (ip->i_diflags2 & XFS_DIFLAG2_DAX)
634 flags |= FS_XFLAG_DAX;
635 if (ip->i_diflags2 & XFS_DIFLAG2_COWEXTSIZE)
636 flags |= FS_XFLAG_COWEXTSIZE;
637 }
638
639 if (xfs_inode_has_attr_fork(ip))
640 flags |= FS_XFLAG_HASATTR;
641 return flags;
642}
643
644/*
645 * Lookups up an inode from "name". If ci_name is not NULL, then a CI match
646 * is allowed, otherwise it has to be an exact match. If a CI match is found,
647 * ci_name->name will point to a the actual name (caller must free) or
648 * will be set to NULL if an exact match is found.
649 */
650int
651xfs_lookup(
652 struct xfs_inode *dp,
653 const struct xfs_name *name,
654 struct xfs_inode **ipp,
655 struct xfs_name *ci_name)
656{
657 xfs_ino_t inum;
658 int error;
659
660 trace_xfs_lookup(dp, name);
661
662 if (xfs_is_shutdown(dp->i_mount))
663 return -EIO;
664
665 error = xfs_dir_lookup(NULL, dp, name, &inum, ci_name);
666 if (error)
667 goto out_unlock;
668
669 error = xfs_iget(dp->i_mount, NULL, inum, 0, 0, ipp);
670 if (error)
671 goto out_free_name;
672
673 return 0;
674
675out_free_name:
676 if (ci_name)
677 kmem_free(ci_name->name);
678out_unlock:
679 *ipp = NULL;
680 return error;
681}
682
683/* Propagate di_flags from a parent inode to a child inode. */
684static void
685xfs_inode_inherit_flags(
686 struct xfs_inode *ip,
687 const struct xfs_inode *pip)
688{
689 unsigned int di_flags = 0;
690 xfs_failaddr_t failaddr;
691 umode_t mode = VFS_I(ip)->i_mode;
692
693 if (S_ISDIR(mode)) {
694 if (pip->i_diflags & XFS_DIFLAG_RTINHERIT)
695 di_flags |= XFS_DIFLAG_RTINHERIT;
696 if (pip->i_diflags & XFS_DIFLAG_EXTSZINHERIT) {
697 di_flags |= XFS_DIFLAG_EXTSZINHERIT;
698 ip->i_extsize = pip->i_extsize;
699 }
700 if (pip->i_diflags & XFS_DIFLAG_PROJINHERIT)
701 di_flags |= XFS_DIFLAG_PROJINHERIT;
702 } else if (S_ISREG(mode)) {
703 if ((pip->i_diflags & XFS_DIFLAG_RTINHERIT) &&
704 xfs_has_realtime(ip->i_mount))
705 di_flags |= XFS_DIFLAG_REALTIME;
706 if (pip->i_diflags & XFS_DIFLAG_EXTSZINHERIT) {
707 di_flags |= XFS_DIFLAG_EXTSIZE;
708 ip->i_extsize = pip->i_extsize;
709 }
710 }
711 if ((pip->i_diflags & XFS_DIFLAG_NOATIME) &&
712 xfs_inherit_noatime)
713 di_flags |= XFS_DIFLAG_NOATIME;
714 if ((pip->i_diflags & XFS_DIFLAG_NODUMP) &&
715 xfs_inherit_nodump)
716 di_flags |= XFS_DIFLAG_NODUMP;
717 if ((pip->i_diflags & XFS_DIFLAG_SYNC) &&
718 xfs_inherit_sync)
719 di_flags |= XFS_DIFLAG_SYNC;
720 if ((pip->i_diflags & XFS_DIFLAG_NOSYMLINKS) &&
721 xfs_inherit_nosymlinks)
722 di_flags |= XFS_DIFLAG_NOSYMLINKS;
723 if ((pip->i_diflags & XFS_DIFLAG_NODEFRAG) &&
724 xfs_inherit_nodefrag)
725 di_flags |= XFS_DIFLAG_NODEFRAG;
726 if (pip->i_diflags & XFS_DIFLAG_FILESTREAM)
727 di_flags |= XFS_DIFLAG_FILESTREAM;
728
729 ip->i_diflags |= di_flags;
730
731 /*
732 * Inode verifiers on older kernels only check that the extent size
733 * hint is an integer multiple of the rt extent size on realtime files.
734 * They did not check the hint alignment on a directory with both
735 * rtinherit and extszinherit flags set. If the misaligned hint is
736 * propagated from a directory into a new realtime file, new file
737 * allocations will fail due to math errors in the rt allocator and/or
738 * trip the verifiers. Validate the hint settings in the new file so
739 * that we don't let broken hints propagate.
740 */
741 failaddr = xfs_inode_validate_extsize(ip->i_mount, ip->i_extsize,
742 VFS_I(ip)->i_mode, ip->i_diflags);
743 if (failaddr) {
744 ip->i_diflags &= ~(XFS_DIFLAG_EXTSIZE |
745 XFS_DIFLAG_EXTSZINHERIT);
746 ip->i_extsize = 0;
747 }
748}
749
750/* Propagate di_flags2 from a parent inode to a child inode. */
751static void
752xfs_inode_inherit_flags2(
753 struct xfs_inode *ip,
754 const struct xfs_inode *pip)
755{
756 xfs_failaddr_t failaddr;
757
758 if (pip->i_diflags2 & XFS_DIFLAG2_COWEXTSIZE) {
759 ip->i_diflags2 |= XFS_DIFLAG2_COWEXTSIZE;
760 ip->i_cowextsize = pip->i_cowextsize;
761 }
762 if (pip->i_diflags2 & XFS_DIFLAG2_DAX)
763 ip->i_diflags2 |= XFS_DIFLAG2_DAX;
764
765 /* Don't let invalid cowextsize hints propagate. */
766 failaddr = xfs_inode_validate_cowextsize(ip->i_mount, ip->i_cowextsize,
767 VFS_I(ip)->i_mode, ip->i_diflags, ip->i_diflags2);
768 if (failaddr) {
769 ip->i_diflags2 &= ~XFS_DIFLAG2_COWEXTSIZE;
770 ip->i_cowextsize = 0;
771 }
772}
773
774/*
775 * Initialise a newly allocated inode and return the in-core inode to the
776 * caller locked exclusively.
777 */
778int
779xfs_init_new_inode(
780 struct user_namespace *mnt_userns,
781 struct xfs_trans *tp,
782 struct xfs_inode *pip,
783 xfs_ino_t ino,
784 umode_t mode,
785 xfs_nlink_t nlink,
786 dev_t rdev,
787 prid_t prid,
788 bool init_xattrs,
789 struct xfs_inode **ipp)
790{
791 struct inode *dir = pip ? VFS_I(pip) : NULL;
792 struct xfs_mount *mp = tp->t_mountp;
793 struct xfs_inode *ip;
794 unsigned int flags;
795 int error;
796 struct timespec64 tv;
797 struct inode *inode;
798
799 /*
800 * Protect against obviously corrupt allocation btree records. Later
801 * xfs_iget checks will catch re-allocation of other active in-memory
802 * and on-disk inodes. If we don't catch reallocating the parent inode
803 * here we will deadlock in xfs_iget() so we have to do these checks
804 * first.
805 */
806 if ((pip && ino == pip->i_ino) || !xfs_verify_dir_ino(mp, ino)) {
807 xfs_alert(mp, "Allocated a known in-use inode 0x%llx!", ino);
808 return -EFSCORRUPTED;
809 }
810
811 /*
812 * Get the in-core inode with the lock held exclusively to prevent
813 * others from looking at until we're done.
814 */
815 error = xfs_iget(mp, tp, ino, XFS_IGET_CREATE, XFS_ILOCK_EXCL, &ip);
816 if (error)
817 return error;
818
819 ASSERT(ip != NULL);
820 inode = VFS_I(ip);
821 set_nlink(inode, nlink);
822 inode->i_rdev = rdev;
823 ip->i_projid = prid;
824
825 if (dir && !(dir->i_mode & S_ISGID) && xfs_has_grpid(mp)) {
826 inode_fsuid_set(inode, mnt_userns);
827 inode->i_gid = dir->i_gid;
828 inode->i_mode = mode;
829 } else {
830 inode_init_owner(mnt_userns, inode, dir, mode);
831 }
832
833 /*
834 * If the group ID of the new file does not match the effective group
835 * ID or one of the supplementary group IDs, the S_ISGID bit is cleared
836 * (and only if the irix_sgid_inherit compatibility variable is set).
837 */
838 if (irix_sgid_inherit && (inode->i_mode & S_ISGID) &&
839 !vfsgid_in_group_p(i_gid_into_vfsgid(mnt_userns, inode)))
840 inode->i_mode &= ~S_ISGID;
841
842 ip->i_disk_size = 0;
843 ip->i_df.if_nextents = 0;
844 ASSERT(ip->i_nblocks == 0);
845
846 tv = current_time(inode);
847 inode->i_mtime = tv;
848 inode->i_atime = tv;
849 inode->i_ctime = tv;
850
851 ip->i_extsize = 0;
852 ip->i_diflags = 0;
853
854 if (xfs_has_v3inodes(mp)) {
855 inode_set_iversion(inode, 1);
856 ip->i_cowextsize = 0;
857 ip->i_crtime = tv;
858 }
859
860 flags = XFS_ILOG_CORE;
861 switch (mode & S_IFMT) {
862 case S_IFIFO:
863 case S_IFCHR:
864 case S_IFBLK:
865 case S_IFSOCK:
866 ip->i_df.if_format = XFS_DINODE_FMT_DEV;
867 flags |= XFS_ILOG_DEV;
868 break;
869 case S_IFREG:
870 case S_IFDIR:
871 if (pip && (pip->i_diflags & XFS_DIFLAG_ANY))
872 xfs_inode_inherit_flags(ip, pip);
873 if (pip && (pip->i_diflags2 & XFS_DIFLAG2_ANY))
874 xfs_inode_inherit_flags2(ip, pip);
875 fallthrough;
876 case S_IFLNK:
877 ip->i_df.if_format = XFS_DINODE_FMT_EXTENTS;
878 ip->i_df.if_bytes = 0;
879 ip->i_df.if_u1.if_root = NULL;
880 break;
881 default:
882 ASSERT(0);
883 }
884
885 /*
886 * If we need to create attributes immediately after allocating the
887 * inode, initialise an empty attribute fork right now. We use the
888 * default fork offset for attributes here as we don't know exactly what
889 * size or how many attributes we might be adding. We can do this
890 * safely here because we know the data fork is completely empty and
891 * this saves us from needing to run a separate transaction to set the
892 * fork offset in the immediate future.
893 */
894 if (init_xattrs && xfs_has_attr(mp)) {
895 ip->i_forkoff = xfs_default_attroffset(ip) >> 3;
896 xfs_ifork_init_attr(ip, XFS_DINODE_FMT_EXTENTS, 0);
897 }
898
899 /*
900 * Log the new values stuffed into the inode.
901 */
902 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
903 xfs_trans_log_inode(tp, ip, flags);
904
905 /* now that we have an i_mode we can setup the inode structure */
906 xfs_setup_inode(ip);
907
908 *ipp = ip;
909 return 0;
910}
911
912/*
913 * Decrement the link count on an inode & log the change. If this causes the
914 * link count to go to zero, move the inode to AGI unlinked list so that it can
915 * be freed when the last active reference goes away via xfs_inactive().
916 */
917static int /* error */
918xfs_droplink(
919 xfs_trans_t *tp,
920 xfs_inode_t *ip)
921{
922 xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
923
924 drop_nlink(VFS_I(ip));
925 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
926
927 if (VFS_I(ip)->i_nlink)
928 return 0;
929
930 return xfs_iunlink(tp, ip);
931}
932
933/*
934 * Increment the link count on an inode & log the change.
935 */
936static void
937xfs_bumplink(
938 xfs_trans_t *tp,
939 xfs_inode_t *ip)
940{
941 xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
942
943 inc_nlink(VFS_I(ip));
944 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
945}
946
947int
948xfs_create(
949 struct user_namespace *mnt_userns,
950 xfs_inode_t *dp,
951 struct xfs_name *name,
952 umode_t mode,
953 dev_t rdev,
954 bool init_xattrs,
955 xfs_inode_t **ipp)
956{
957 int is_dir = S_ISDIR(mode);
958 struct xfs_mount *mp = dp->i_mount;
959 struct xfs_inode *ip = NULL;
960 struct xfs_trans *tp = NULL;
961 int error;
962 bool unlock_dp_on_error = false;
963 prid_t prid;
964 struct xfs_dquot *udqp = NULL;
965 struct xfs_dquot *gdqp = NULL;
966 struct xfs_dquot *pdqp = NULL;
967 struct xfs_trans_res *tres;
968 uint resblks;
969 xfs_ino_t ino;
970
971 trace_xfs_create(dp, name);
972
973 if (xfs_is_shutdown(mp))
974 return -EIO;
975
976 prid = xfs_get_initial_prid(dp);
977
978 /*
979 * Make sure that we have allocated dquot(s) on disk.
980 */
981 error = xfs_qm_vop_dqalloc(dp, mapped_fsuid(mnt_userns, &init_user_ns),
982 mapped_fsgid(mnt_userns, &init_user_ns), prid,
983 XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
984 &udqp, &gdqp, &pdqp);
985 if (error)
986 return error;
987
988 if (is_dir) {
989 resblks = XFS_MKDIR_SPACE_RES(mp, name->len);
990 tres = &M_RES(mp)->tr_mkdir;
991 } else {
992 resblks = XFS_CREATE_SPACE_RES(mp, name->len);
993 tres = &M_RES(mp)->tr_create;
994 }
995
996 /*
997 * Initially assume that the file does not exist and
998 * reserve the resources for that case. If that is not
999 * the case we'll drop the one we have and get a more
1000 * appropriate transaction later.
1001 */
1002 error = xfs_trans_alloc_icreate(mp, tres, udqp, gdqp, pdqp, resblks,
1003 &tp);
1004 if (error == -ENOSPC) {
1005 /* flush outstanding delalloc blocks and retry */
1006 xfs_flush_inodes(mp);
1007 error = xfs_trans_alloc_icreate(mp, tres, udqp, gdqp, pdqp,
1008 resblks, &tp);
1009 }
1010 if (error)
1011 goto out_release_dquots;
1012
1013 xfs_ilock(dp, XFS_ILOCK_EXCL | XFS_ILOCK_PARENT);
1014 unlock_dp_on_error = true;
1015
1016 /*
1017 * A newly created regular or special file just has one directory
1018 * entry pointing to them, but a directory also the "." entry
1019 * pointing to itself.
1020 */
1021 error = xfs_dialloc(&tp, dp->i_ino, mode, &ino);
1022 if (!error)
1023 error = xfs_init_new_inode(mnt_userns, tp, dp, ino, mode,
1024 is_dir ? 2 : 1, rdev, prid, init_xattrs, &ip);
1025 if (error)
1026 goto out_trans_cancel;
1027
1028 /*
1029 * Now we join the directory inode to the transaction. We do not do it
1030 * earlier because xfs_dialloc might commit the previous transaction
1031 * (and release all the locks). An error from here on will result in
1032 * the transaction cancel unlocking dp so don't do it explicitly in the
1033 * error path.
1034 */
1035 xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
1036 unlock_dp_on_error = false;
1037
1038 error = xfs_dir_createname(tp, dp, name, ip->i_ino,
1039 resblks - XFS_IALLOC_SPACE_RES(mp));
1040 if (error) {
1041 ASSERT(error != -ENOSPC);
1042 goto out_trans_cancel;
1043 }
1044 xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1045 xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
1046
1047 if (is_dir) {
1048 error = xfs_dir_init(tp, ip, dp);
1049 if (error)
1050 goto out_trans_cancel;
1051
1052 xfs_bumplink(tp, dp);
1053 }
1054
1055 /*
1056 * If this is a synchronous mount, make sure that the
1057 * create transaction goes to disk before returning to
1058 * the user.
1059 */
1060 if (xfs_has_wsync(mp) || xfs_has_dirsync(mp))
1061 xfs_trans_set_sync(tp);
1062
1063 /*
1064 * Attach the dquot(s) to the inodes and modify them incore.
1065 * These ids of the inode couldn't have changed since the new
1066 * inode has been locked ever since it was created.
1067 */
1068 xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp, pdqp);
1069
1070 error = xfs_trans_commit(tp);
1071 if (error)
1072 goto out_release_inode;
1073
1074 xfs_qm_dqrele(udqp);
1075 xfs_qm_dqrele(gdqp);
1076 xfs_qm_dqrele(pdqp);
1077
1078 *ipp = ip;
1079 return 0;
1080
1081 out_trans_cancel:
1082 xfs_trans_cancel(tp);
1083 out_release_inode:
1084 /*
1085 * Wait until after the current transaction is aborted to finish the
1086 * setup of the inode and release the inode. This prevents recursive
1087 * transactions and deadlocks from xfs_inactive.
1088 */
1089 if (ip) {
1090 xfs_finish_inode_setup(ip);
1091 xfs_irele(ip);
1092 }
1093 out_release_dquots:
1094 xfs_qm_dqrele(udqp);
1095 xfs_qm_dqrele(gdqp);
1096 xfs_qm_dqrele(pdqp);
1097
1098 if (unlock_dp_on_error)
1099 xfs_iunlock(dp, XFS_ILOCK_EXCL);
1100 return error;
1101}
1102
1103int
1104xfs_create_tmpfile(
1105 struct user_namespace *mnt_userns,
1106 struct xfs_inode *dp,
1107 umode_t mode,
1108 struct xfs_inode **ipp)
1109{
1110 struct xfs_mount *mp = dp->i_mount;
1111 struct xfs_inode *ip = NULL;
1112 struct xfs_trans *tp = NULL;
1113 int error;
1114 prid_t prid;
1115 struct xfs_dquot *udqp = NULL;
1116 struct xfs_dquot *gdqp = NULL;
1117 struct xfs_dquot *pdqp = NULL;
1118 struct xfs_trans_res *tres;
1119 uint resblks;
1120 xfs_ino_t ino;
1121
1122 if (xfs_is_shutdown(mp))
1123 return -EIO;
1124
1125 prid = xfs_get_initial_prid(dp);
1126
1127 /*
1128 * Make sure that we have allocated dquot(s) on disk.
1129 */
1130 error = xfs_qm_vop_dqalloc(dp, mapped_fsuid(mnt_userns, &init_user_ns),
1131 mapped_fsgid(mnt_userns, &init_user_ns), prid,
1132 XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
1133 &udqp, &gdqp, &pdqp);
1134 if (error)
1135 return error;
1136
1137 resblks = XFS_IALLOC_SPACE_RES(mp);
1138 tres = &M_RES(mp)->tr_create_tmpfile;
1139
1140 error = xfs_trans_alloc_icreate(mp, tres, udqp, gdqp, pdqp, resblks,
1141 &tp);
1142 if (error)
1143 goto out_release_dquots;
1144
1145 error = xfs_dialloc(&tp, dp->i_ino, mode, &ino);
1146 if (!error)
1147 error = xfs_init_new_inode(mnt_userns, tp, dp, ino, mode,
1148 0, 0, prid, false, &ip);
1149 if (error)
1150 goto out_trans_cancel;
1151
1152 if (xfs_has_wsync(mp))
1153 xfs_trans_set_sync(tp);
1154
1155 /*
1156 * Attach the dquot(s) to the inodes and modify them incore.
1157 * These ids of the inode couldn't have changed since the new
1158 * inode has been locked ever since it was created.
1159 */
1160 xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp, pdqp);
1161
1162 error = xfs_iunlink(tp, ip);
1163 if (error)
1164 goto out_trans_cancel;
1165
1166 error = xfs_trans_commit(tp);
1167 if (error)
1168 goto out_release_inode;
1169
1170 xfs_qm_dqrele(udqp);
1171 xfs_qm_dqrele(gdqp);
1172 xfs_qm_dqrele(pdqp);
1173
1174 *ipp = ip;
1175 return 0;
1176
1177 out_trans_cancel:
1178 xfs_trans_cancel(tp);
1179 out_release_inode:
1180 /*
1181 * Wait until after the current transaction is aborted to finish the
1182 * setup of the inode and release the inode. This prevents recursive
1183 * transactions and deadlocks from xfs_inactive.
1184 */
1185 if (ip) {
1186 xfs_finish_inode_setup(ip);
1187 xfs_irele(ip);
1188 }
1189 out_release_dquots:
1190 xfs_qm_dqrele(udqp);
1191 xfs_qm_dqrele(gdqp);
1192 xfs_qm_dqrele(pdqp);
1193
1194 return error;
1195}
1196
1197int
1198xfs_link(
1199 xfs_inode_t *tdp,
1200 xfs_inode_t *sip,
1201 struct xfs_name *target_name)
1202{
1203 xfs_mount_t *mp = tdp->i_mount;
1204 xfs_trans_t *tp;
1205 int error, nospace_error = 0;
1206 int resblks;
1207
1208 trace_xfs_link(tdp, target_name);
1209
1210 ASSERT(!S_ISDIR(VFS_I(sip)->i_mode));
1211
1212 if (xfs_is_shutdown(mp))
1213 return -EIO;
1214
1215 error = xfs_qm_dqattach(sip);
1216 if (error)
1217 goto std_return;
1218
1219 error = xfs_qm_dqattach(tdp);
1220 if (error)
1221 goto std_return;
1222
1223 resblks = XFS_LINK_SPACE_RES(mp, target_name->len);
1224 error = xfs_trans_alloc_dir(tdp, &M_RES(mp)->tr_link, sip, &resblks,
1225 &tp, &nospace_error);
1226 if (error)
1227 goto std_return;
1228
1229 /*
1230 * If we are using project inheritance, we only allow hard link
1231 * creation in our tree when the project IDs are the same; else
1232 * the tree quota mechanism could be circumvented.
1233 */
1234 if (unlikely((tdp->i_diflags & XFS_DIFLAG_PROJINHERIT) &&
1235 tdp->i_projid != sip->i_projid)) {
1236 error = -EXDEV;
1237 goto error_return;
1238 }
1239
1240 if (!resblks) {
1241 error = xfs_dir_canenter(tp, tdp, target_name);
1242 if (error)
1243 goto error_return;
1244 }
1245
1246 /*
1247 * Handle initial link state of O_TMPFILE inode
1248 */
1249 if (VFS_I(sip)->i_nlink == 0) {
1250 struct xfs_perag *pag;
1251
1252 pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, sip->i_ino));
1253 error = xfs_iunlink_remove(tp, pag, sip);
1254 xfs_perag_put(pag);
1255 if (error)
1256 goto error_return;
1257 }
1258
1259 error = xfs_dir_createname(tp, tdp, target_name, sip->i_ino,
1260 resblks);
1261 if (error)
1262 goto error_return;
1263 xfs_trans_ichgtime(tp, tdp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1264 xfs_trans_log_inode(tp, tdp, XFS_ILOG_CORE);
1265
1266 xfs_bumplink(tp, sip);
1267
1268 /*
1269 * If this is a synchronous mount, make sure that the
1270 * link transaction goes to disk before returning to
1271 * the user.
1272 */
1273 if (xfs_has_wsync(mp) || xfs_has_dirsync(mp))
1274 xfs_trans_set_sync(tp);
1275
1276 return xfs_trans_commit(tp);
1277
1278 error_return:
1279 xfs_trans_cancel(tp);
1280 std_return:
1281 if (error == -ENOSPC && nospace_error)
1282 error = nospace_error;
1283 return error;
1284}
1285
1286/* Clear the reflink flag and the cowblocks tag if possible. */
1287static void
1288xfs_itruncate_clear_reflink_flags(
1289 struct xfs_inode *ip)
1290{
1291 struct xfs_ifork *dfork;
1292 struct xfs_ifork *cfork;
1293
1294 if (!xfs_is_reflink_inode(ip))
1295 return;
1296 dfork = xfs_ifork_ptr(ip, XFS_DATA_FORK);
1297 cfork = xfs_ifork_ptr(ip, XFS_COW_FORK);
1298 if (dfork->if_bytes == 0 && cfork->if_bytes == 0)
1299 ip->i_diflags2 &= ~XFS_DIFLAG2_REFLINK;
1300 if (cfork->if_bytes == 0)
1301 xfs_inode_clear_cowblocks_tag(ip);
1302}
1303
1304/*
1305 * Free up the underlying blocks past new_size. The new size must be smaller
1306 * than the current size. This routine can be used both for the attribute and
1307 * data fork, and does not modify the inode size, which is left to the caller.
1308 *
1309 * The transaction passed to this routine must have made a permanent log
1310 * reservation of at least XFS_ITRUNCATE_LOG_RES. This routine may commit the
1311 * given transaction and start new ones, so make sure everything involved in
1312 * the transaction is tidy before calling here. Some transaction will be
1313 * returned to the caller to be committed. The incoming transaction must
1314 * already include the inode, and both inode locks must be held exclusively.
1315 * The inode must also be "held" within the transaction. On return the inode
1316 * will be "held" within the returned transaction. This routine does NOT
1317 * require any disk space to be reserved for it within the transaction.
1318 *
1319 * If we get an error, we must return with the inode locked and linked into the
1320 * current transaction. This keeps things simple for the higher level code,
1321 * because it always knows that the inode is locked and held in the transaction
1322 * that returns to it whether errors occur or not. We don't mark the inode
1323 * dirty on error so that transactions can be easily aborted if possible.
1324 */
1325int
1326xfs_itruncate_extents_flags(
1327 struct xfs_trans **tpp,
1328 struct xfs_inode *ip,
1329 int whichfork,
1330 xfs_fsize_t new_size,
1331 int flags)
1332{
1333 struct xfs_mount *mp = ip->i_mount;
1334 struct xfs_trans *tp = *tpp;
1335 xfs_fileoff_t first_unmap_block;
1336 xfs_filblks_t unmap_len;
1337 int error = 0;
1338
1339 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
1340 ASSERT(!atomic_read(&VFS_I(ip)->i_count) ||
1341 xfs_isilocked(ip, XFS_IOLOCK_EXCL));
1342 ASSERT(new_size <= XFS_ISIZE(ip));
1343 ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
1344 ASSERT(ip->i_itemp != NULL);
1345 ASSERT(ip->i_itemp->ili_lock_flags == 0);
1346 ASSERT(!XFS_NOT_DQATTACHED(mp, ip));
1347
1348 trace_xfs_itruncate_extents_start(ip, new_size);
1349
1350 flags |= xfs_bmapi_aflag(whichfork);
1351
1352 /*
1353 * Since it is possible for space to become allocated beyond
1354 * the end of the file (in a crash where the space is allocated
1355 * but the inode size is not yet updated), simply remove any
1356 * blocks which show up between the new EOF and the maximum
1357 * possible file size.
1358 *
1359 * We have to free all the blocks to the bmbt maximum offset, even if
1360 * the page cache can't scale that far.
1361 */
1362 first_unmap_block = XFS_B_TO_FSB(mp, (xfs_ufsize_t)new_size);
1363 if (!xfs_verify_fileoff(mp, first_unmap_block)) {
1364 WARN_ON_ONCE(first_unmap_block > XFS_MAX_FILEOFF);
1365 return 0;
1366 }
1367
1368 unmap_len = XFS_MAX_FILEOFF - first_unmap_block + 1;
1369 while (unmap_len > 0) {
1370 ASSERT(tp->t_firstblock == NULLFSBLOCK);
1371 error = __xfs_bunmapi(tp, ip, first_unmap_block, &unmap_len,
1372 flags, XFS_ITRUNC_MAX_EXTENTS);
1373 if (error)
1374 goto out;
1375
1376 /* free the just unmapped extents */
1377 error = xfs_defer_finish(&tp);
1378 if (error)
1379 goto out;
1380 }
1381
1382 if (whichfork == XFS_DATA_FORK) {
1383 /* Remove all pending CoW reservations. */
1384 error = xfs_reflink_cancel_cow_blocks(ip, &tp,
1385 first_unmap_block, XFS_MAX_FILEOFF, true);
1386 if (error)
1387 goto out;
1388
1389 xfs_itruncate_clear_reflink_flags(ip);
1390 }
1391
1392 /*
1393 * Always re-log the inode so that our permanent transaction can keep
1394 * on rolling it forward in the log.
1395 */
1396 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1397
1398 trace_xfs_itruncate_extents_end(ip, new_size);
1399
1400out:
1401 *tpp = tp;
1402 return error;
1403}
1404
1405int
1406xfs_release(
1407 xfs_inode_t *ip)
1408{
1409 xfs_mount_t *mp = ip->i_mount;
1410 int error = 0;
1411
1412 if (!S_ISREG(VFS_I(ip)->i_mode) || (VFS_I(ip)->i_mode == 0))
1413 return 0;
1414
1415 /* If this is a read-only mount, don't do this (would generate I/O) */
1416 if (xfs_is_readonly(mp))
1417 return 0;
1418
1419 if (!xfs_is_shutdown(mp)) {
1420 int truncated;
1421
1422 /*
1423 * If we previously truncated this file and removed old data
1424 * in the process, we want to initiate "early" writeout on
1425 * the last close. This is an attempt to combat the notorious
1426 * NULL files problem which is particularly noticeable from a
1427 * truncate down, buffered (re-)write (delalloc), followed by
1428 * a crash. What we are effectively doing here is
1429 * significantly reducing the time window where we'd otherwise
1430 * be exposed to that problem.
1431 */
1432 truncated = xfs_iflags_test_and_clear(ip, XFS_ITRUNCATED);
1433 if (truncated) {
1434 xfs_iflags_clear(ip, XFS_IDIRTY_RELEASE);
1435 if (ip->i_delayed_blks > 0) {
1436 error = filemap_flush(VFS_I(ip)->i_mapping);
1437 if (error)
1438 return error;
1439 }
1440 }
1441 }
1442
1443 if (VFS_I(ip)->i_nlink == 0)
1444 return 0;
1445
1446 /*
1447 * If we can't get the iolock just skip truncating the blocks past EOF
1448 * because we could deadlock with the mmap_lock otherwise. We'll get
1449 * another chance to drop them once the last reference to the inode is
1450 * dropped, so we'll never leak blocks permanently.
1451 */
1452 if (!xfs_ilock_nowait(ip, XFS_IOLOCK_EXCL))
1453 return 0;
1454
1455 if (xfs_can_free_eofblocks(ip, false)) {
1456 /*
1457 * Check if the inode is being opened, written and closed
1458 * frequently and we have delayed allocation blocks outstanding
1459 * (e.g. streaming writes from the NFS server), truncating the
1460 * blocks past EOF will cause fragmentation to occur.
1461 *
1462 * In this case don't do the truncation, but we have to be
1463 * careful how we detect this case. Blocks beyond EOF show up as
1464 * i_delayed_blks even when the inode is clean, so we need to
1465 * truncate them away first before checking for a dirty release.
1466 * Hence on the first dirty close we will still remove the
1467 * speculative allocation, but after that we will leave it in
1468 * place.
1469 */
1470 if (xfs_iflags_test(ip, XFS_IDIRTY_RELEASE))
1471 goto out_unlock;
1472
1473 error = xfs_free_eofblocks(ip);
1474 if (error)
1475 goto out_unlock;
1476
1477 /* delalloc blocks after truncation means it really is dirty */
1478 if (ip->i_delayed_blks)
1479 xfs_iflags_set(ip, XFS_IDIRTY_RELEASE);
1480 }
1481
1482out_unlock:
1483 xfs_iunlock(ip, XFS_IOLOCK_EXCL);
1484 return error;
1485}
1486
1487/*
1488 * xfs_inactive_truncate
1489 *
1490 * Called to perform a truncate when an inode becomes unlinked.
1491 */
1492STATIC int
1493xfs_inactive_truncate(
1494 struct xfs_inode *ip)
1495{
1496 struct xfs_mount *mp = ip->i_mount;
1497 struct xfs_trans *tp;
1498 int error;
1499
1500 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, 0, 0, 0, &tp);
1501 if (error) {
1502 ASSERT(xfs_is_shutdown(mp));
1503 return error;
1504 }
1505 xfs_ilock(ip, XFS_ILOCK_EXCL);
1506 xfs_trans_ijoin(tp, ip, 0);
1507
1508 /*
1509 * Log the inode size first to prevent stale data exposure in the event
1510 * of a system crash before the truncate completes. See the related
1511 * comment in xfs_vn_setattr_size() for details.
1512 */
1513 ip->i_disk_size = 0;
1514 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1515
1516 error = xfs_itruncate_extents(&tp, ip, XFS_DATA_FORK, 0);
1517 if (error)
1518 goto error_trans_cancel;
1519
1520 ASSERT(ip->i_df.if_nextents == 0);
1521
1522 error = xfs_trans_commit(tp);
1523 if (error)
1524 goto error_unlock;
1525
1526 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1527 return 0;
1528
1529error_trans_cancel:
1530 xfs_trans_cancel(tp);
1531error_unlock:
1532 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1533 return error;
1534}
1535
1536/*
1537 * xfs_inactive_ifree()
1538 *
1539 * Perform the inode free when an inode is unlinked.
1540 */
1541STATIC int
1542xfs_inactive_ifree(
1543 struct xfs_inode *ip)
1544{
1545 struct xfs_mount *mp = ip->i_mount;
1546 struct xfs_trans *tp;
1547 int error;
1548
1549 /*
1550 * We try to use a per-AG reservation for any block needed by the finobt
1551 * tree, but as the finobt feature predates the per-AG reservation
1552 * support a degraded file system might not have enough space for the
1553 * reservation at mount time. In that case try to dip into the reserved
1554 * pool and pray.
1555 *
1556 * Send a warning if the reservation does happen to fail, as the inode
1557 * now remains allocated and sits on the unlinked list until the fs is
1558 * repaired.
1559 */
1560 if (unlikely(mp->m_finobt_nores)) {
1561 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ifree,
1562 XFS_IFREE_SPACE_RES(mp), 0, XFS_TRANS_RESERVE,
1563 &tp);
1564 } else {
1565 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ifree, 0, 0, 0, &tp);
1566 }
1567 if (error) {
1568 if (error == -ENOSPC) {
1569 xfs_warn_ratelimited(mp,
1570 "Failed to remove inode(s) from unlinked list. "
1571 "Please free space, unmount and run xfs_repair.");
1572 } else {
1573 ASSERT(xfs_is_shutdown(mp));
1574 }
1575 return error;
1576 }
1577
1578 /*
1579 * We do not hold the inode locked across the entire rolling transaction
1580 * here. We only need to hold it for the first transaction that
1581 * xfs_ifree() builds, which may mark the inode XFS_ISTALE if the
1582 * underlying cluster buffer is freed. Relogging an XFS_ISTALE inode
1583 * here breaks the relationship between cluster buffer invalidation and
1584 * stale inode invalidation on cluster buffer item journal commit
1585 * completion, and can result in leaving dirty stale inodes hanging
1586 * around in memory.
1587 *
1588 * We have no need for serialising this inode operation against other
1589 * operations - we freed the inode and hence reallocation is required
1590 * and that will serialise on reallocating the space the deferops need
1591 * to free. Hence we can unlock the inode on the first commit of
1592 * the transaction rather than roll it right through the deferops. This
1593 * avoids relogging the XFS_ISTALE inode.
1594 *
1595 * We check that xfs_ifree() hasn't grown an internal transaction roll
1596 * by asserting that the inode is still locked when it returns.
1597 */
1598 xfs_ilock(ip, XFS_ILOCK_EXCL);
1599 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
1600
1601 error = xfs_ifree(tp, ip);
1602 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
1603 if (error) {
1604 /*
1605 * If we fail to free the inode, shut down. The cancel
1606 * might do that, we need to make sure. Otherwise the
1607 * inode might be lost for a long time or forever.
1608 */
1609 if (!xfs_is_shutdown(mp)) {
1610 xfs_notice(mp, "%s: xfs_ifree returned error %d",
1611 __func__, error);
1612 xfs_force_shutdown(mp, SHUTDOWN_META_IO_ERROR);
1613 }
1614 xfs_trans_cancel(tp);
1615 return error;
1616 }
1617
1618 /*
1619 * Credit the quota account(s). The inode is gone.
1620 */
1621 xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_ICOUNT, -1);
1622
1623 /*
1624 * Just ignore errors at this point. There is nothing we can do except
1625 * to try to keep going. Make sure it's not a silent error.
1626 */
1627 error = xfs_trans_commit(tp);
1628 if (error)
1629 xfs_notice(mp, "%s: xfs_trans_commit returned error %d",
1630 __func__, error);
1631
1632 return 0;
1633}
1634
1635/*
1636 * Returns true if we need to update the on-disk metadata before we can free
1637 * the memory used by this inode. Updates include freeing post-eof
1638 * preallocations; freeing COW staging extents; and marking the inode free in
1639 * the inobt if it is on the unlinked list.
1640 */
1641bool
1642xfs_inode_needs_inactive(
1643 struct xfs_inode *ip)
1644{
1645 struct xfs_mount *mp = ip->i_mount;
1646 struct xfs_ifork *cow_ifp = xfs_ifork_ptr(ip, XFS_COW_FORK);
1647
1648 /*
1649 * If the inode is already free, then there can be nothing
1650 * to clean up here.
1651 */
1652 if (VFS_I(ip)->i_mode == 0)
1653 return false;
1654
1655 /* If this is a read-only mount, don't do this (would generate I/O) */
1656 if (xfs_is_readonly(mp))
1657 return false;
1658
1659 /* If the log isn't running, push inodes straight to reclaim. */
1660 if (xfs_is_shutdown(mp) || xfs_has_norecovery(mp))
1661 return false;
1662
1663 /* Metadata inodes require explicit resource cleanup. */
1664 if (xfs_is_metadata_inode(ip))
1665 return false;
1666
1667 /* Want to clean out the cow blocks if there are any. */
1668 if (cow_ifp && cow_ifp->if_bytes > 0)
1669 return true;
1670
1671 /* Unlinked files must be freed. */
1672 if (VFS_I(ip)->i_nlink == 0)
1673 return true;
1674
1675 /*
1676 * This file isn't being freed, so check if there are post-eof blocks
1677 * to free. @force is true because we are evicting an inode from the
1678 * cache. Post-eof blocks must be freed, lest we end up with broken
1679 * free space accounting.
1680 *
1681 * Note: don't bother with iolock here since lockdep complains about
1682 * acquiring it in reclaim context. We have the only reference to the
1683 * inode at this point anyways.
1684 */
1685 return xfs_can_free_eofblocks(ip, true);
1686}
1687
1688/*
1689 * xfs_inactive
1690 *
1691 * This is called when the vnode reference count for the vnode
1692 * goes to zero. If the file has been unlinked, then it must
1693 * now be truncated. Also, we clear all of the read-ahead state
1694 * kept for the inode here since the file is now closed.
1695 */
1696void
1697xfs_inactive(
1698 xfs_inode_t *ip)
1699{
1700 struct xfs_mount *mp;
1701 int error;
1702 int truncate = 0;
1703
1704 /*
1705 * If the inode is already free, then there can be nothing
1706 * to clean up here.
1707 */
1708 if (VFS_I(ip)->i_mode == 0) {
1709 ASSERT(ip->i_df.if_broot_bytes == 0);
1710 goto out;
1711 }
1712
1713 mp = ip->i_mount;
1714 ASSERT(!xfs_iflags_test(ip, XFS_IRECOVERY));
1715
1716 /* If this is a read-only mount, don't do this (would generate I/O) */
1717 if (xfs_is_readonly(mp))
1718 goto out;
1719
1720 /* Metadata inodes require explicit resource cleanup. */
1721 if (xfs_is_metadata_inode(ip))
1722 goto out;
1723
1724 /* Try to clean out the cow blocks if there are any. */
1725 if (xfs_inode_has_cow_data(ip))
1726 xfs_reflink_cancel_cow_range(ip, 0, NULLFILEOFF, true);
1727
1728 if (VFS_I(ip)->i_nlink != 0) {
1729 /*
1730 * force is true because we are evicting an inode from the
1731 * cache. Post-eof blocks must be freed, lest we end up with
1732 * broken free space accounting.
1733 *
1734 * Note: don't bother with iolock here since lockdep complains
1735 * about acquiring it in reclaim context. We have the only
1736 * reference to the inode at this point anyways.
1737 */
1738 if (xfs_can_free_eofblocks(ip, true))
1739 xfs_free_eofblocks(ip);
1740
1741 goto out;
1742 }
1743
1744 if (S_ISREG(VFS_I(ip)->i_mode) &&
1745 (ip->i_disk_size != 0 || XFS_ISIZE(ip) != 0 ||
1746 ip->i_df.if_nextents > 0 || ip->i_delayed_blks > 0))
1747 truncate = 1;
1748
1749 error = xfs_qm_dqattach(ip);
1750 if (error)
1751 goto out;
1752
1753 if (S_ISLNK(VFS_I(ip)->i_mode))
1754 error = xfs_inactive_symlink(ip);
1755 else if (truncate)
1756 error = xfs_inactive_truncate(ip);
1757 if (error)
1758 goto out;
1759
1760 /*
1761 * If there are attributes associated with the file then blow them away
1762 * now. The code calls a routine that recursively deconstructs the
1763 * attribute fork. If also blows away the in-core attribute fork.
1764 */
1765 if (xfs_inode_has_attr_fork(ip)) {
1766 error = xfs_attr_inactive(ip);
1767 if (error)
1768 goto out;
1769 }
1770
1771 ASSERT(ip->i_forkoff == 0);
1772
1773 /*
1774 * Free the inode.
1775 */
1776 xfs_inactive_ifree(ip);
1777
1778out:
1779 /*
1780 * We're done making metadata updates for this inode, so we can release
1781 * the attached dquots.
1782 */
1783 xfs_qm_dqdetach(ip);
1784}
1785
1786/*
1787 * In-Core Unlinked List Lookups
1788 * =============================
1789 *
1790 * Every inode is supposed to be reachable from some other piece of metadata
1791 * with the exception of the root directory. Inodes with a connection to a
1792 * file descriptor but not linked from anywhere in the on-disk directory tree
1793 * are collectively known as unlinked inodes, though the filesystem itself
1794 * maintains links to these inodes so that on-disk metadata are consistent.
1795 *
1796 * XFS implements a per-AG on-disk hash table of unlinked inodes. The AGI
1797 * header contains a number of buckets that point to an inode, and each inode
1798 * record has a pointer to the next inode in the hash chain. This
1799 * singly-linked list causes scaling problems in the iunlink remove function
1800 * because we must walk that list to find the inode that points to the inode
1801 * being removed from the unlinked hash bucket list.
1802 *
1803 * Hence we keep an in-memory double linked list to link each inode on an
1804 * unlinked list. Because there are 64 unlinked lists per AGI, keeping pointer
1805 * based lists would require having 64 list heads in the perag, one for each
1806 * list. This is expensive in terms of memory (think millions of AGs) and cache
1807 * misses on lookups. Instead, use the fact that inodes on the unlinked list
1808 * must be referenced at the VFS level to keep them on the list and hence we
1809 * have an existence guarantee for inodes on the unlinked list.
1810 *
1811 * Given we have an existence guarantee, we can use lockless inode cache lookups
1812 * to resolve aginos to xfs inodes. This means we only need 8 bytes per inode
1813 * for the double linked unlinked list, and we don't need any extra locking to
1814 * keep the list safe as all manipulations are done under the AGI buffer lock.
1815 * Keeping the list up to date does not require memory allocation, just finding
1816 * the XFS inode and updating the next/prev unlinked list aginos.
1817 */
1818
1819/*
1820 * Find an inode on the unlinked list. This does not take references to the
1821 * inode as we have existence guarantees by holding the AGI buffer lock and that
1822 * only unlinked, referenced inodes can be on the unlinked inode list. If we
1823 * don't find the inode in cache, then let the caller handle the situation.
1824 */
1825static struct xfs_inode *
1826xfs_iunlink_lookup(
1827 struct xfs_perag *pag,
1828 xfs_agino_t agino)
1829{
1830 struct xfs_inode *ip;
1831
1832 rcu_read_lock();
1833 ip = radix_tree_lookup(&pag->pag_ici_root, agino);
1834
1835 /*
1836 * Inode not in memory or in RCU freeing limbo should not happen.
1837 * Warn about this and let the caller handle the failure.
1838 */
1839 if (WARN_ON_ONCE(!ip || !ip->i_ino)) {
1840 rcu_read_unlock();
1841 return NULL;
1842 }
1843 ASSERT(!xfs_iflags_test(ip, XFS_IRECLAIMABLE | XFS_IRECLAIM));
1844 rcu_read_unlock();
1845 return ip;
1846}
1847
1848/* Update the prev pointer of the next agino. */
1849static int
1850xfs_iunlink_update_backref(
1851 struct xfs_perag *pag,
1852 xfs_agino_t prev_agino,
1853 xfs_agino_t next_agino)
1854{
1855 struct xfs_inode *ip;
1856
1857 /* No update necessary if we are at the end of the list. */
1858 if (next_agino == NULLAGINO)
1859 return 0;
1860
1861 ip = xfs_iunlink_lookup(pag, next_agino);
1862 if (!ip)
1863 return -EFSCORRUPTED;
1864 ip->i_prev_unlinked = prev_agino;
1865 return 0;
1866}
1867
1868/*
1869 * Point the AGI unlinked bucket at an inode and log the results. The caller
1870 * is responsible for validating the old value.
1871 */
1872STATIC int
1873xfs_iunlink_update_bucket(
1874 struct xfs_trans *tp,
1875 struct xfs_perag *pag,
1876 struct xfs_buf *agibp,
1877 unsigned int bucket_index,
1878 xfs_agino_t new_agino)
1879{
1880 struct xfs_agi *agi = agibp->b_addr;
1881 xfs_agino_t old_value;
1882 int offset;
1883
1884 ASSERT(xfs_verify_agino_or_null(pag, new_agino));
1885
1886 old_value = be32_to_cpu(agi->agi_unlinked[bucket_index]);
1887 trace_xfs_iunlink_update_bucket(tp->t_mountp, pag->pag_agno, bucket_index,
1888 old_value, new_agino);
1889
1890 /*
1891 * We should never find the head of the list already set to the value
1892 * passed in because either we're adding or removing ourselves from the
1893 * head of the list.
1894 */
1895 if (old_value == new_agino) {
1896 xfs_buf_mark_corrupt(agibp);
1897 return -EFSCORRUPTED;
1898 }
1899
1900 agi->agi_unlinked[bucket_index] = cpu_to_be32(new_agino);
1901 offset = offsetof(struct xfs_agi, agi_unlinked) +
1902 (sizeof(xfs_agino_t) * bucket_index);
1903 xfs_trans_log_buf(tp, agibp, offset, offset + sizeof(xfs_agino_t) - 1);
1904 return 0;
1905}
1906
1907static int
1908xfs_iunlink_insert_inode(
1909 struct xfs_trans *tp,
1910 struct xfs_perag *pag,
1911 struct xfs_buf *agibp,
1912 struct xfs_inode *ip)
1913{
1914 struct xfs_mount *mp = tp->t_mountp;
1915 struct xfs_agi *agi = agibp->b_addr;
1916 xfs_agino_t next_agino;
1917 xfs_agino_t agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
1918 short bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
1919 int error;
1920
1921 /*
1922 * Get the index into the agi hash table for the list this inode will
1923 * go on. Make sure the pointer isn't garbage and that this inode
1924 * isn't already on the list.
1925 */
1926 next_agino = be32_to_cpu(agi->agi_unlinked[bucket_index]);
1927 if (next_agino == agino ||
1928 !xfs_verify_agino_or_null(pag, next_agino)) {
1929 xfs_buf_mark_corrupt(agibp);
1930 return -EFSCORRUPTED;
1931 }
1932
1933 /*
1934 * Update the prev pointer in the next inode to point back to this
1935 * inode.
1936 */
1937 error = xfs_iunlink_update_backref(pag, agino, next_agino);
1938 if (error)
1939 return error;
1940
1941 if (next_agino != NULLAGINO) {
1942 /*
1943 * There is already another inode in the bucket, so point this
1944 * inode to the current head of the list.
1945 */
1946 error = xfs_iunlink_log_inode(tp, ip, pag, next_agino);
1947 if (error)
1948 return error;
1949 ip->i_next_unlinked = next_agino;
1950 }
1951
1952 /* Point the head of the list to point to this inode. */
1953 return xfs_iunlink_update_bucket(tp, pag, agibp, bucket_index, agino);
1954}
1955
1956/*
1957 * This is called when the inode's link count has gone to 0 or we are creating
1958 * a tmpfile via O_TMPFILE. The inode @ip must have nlink == 0.
1959 *
1960 * We place the on-disk inode on a list in the AGI. It will be pulled from this
1961 * list when the inode is freed.
1962 */
1963STATIC int
1964xfs_iunlink(
1965 struct xfs_trans *tp,
1966 struct xfs_inode *ip)
1967{
1968 struct xfs_mount *mp = tp->t_mountp;
1969 struct xfs_perag *pag;
1970 struct xfs_buf *agibp;
1971 int error;
1972
1973 ASSERT(VFS_I(ip)->i_nlink == 0);
1974 ASSERT(VFS_I(ip)->i_mode != 0);
1975 trace_xfs_iunlink(ip);
1976
1977 pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));
1978
1979 /* Get the agi buffer first. It ensures lock ordering on the list. */
1980 error = xfs_read_agi(pag, tp, &agibp);
1981 if (error)
1982 goto out;
1983
1984 error = xfs_iunlink_insert_inode(tp, pag, agibp, ip);
1985out:
1986 xfs_perag_put(pag);
1987 return error;
1988}
1989
1990static int
1991xfs_iunlink_remove_inode(
1992 struct xfs_trans *tp,
1993 struct xfs_perag *pag,
1994 struct xfs_buf *agibp,
1995 struct xfs_inode *ip)
1996{
1997 struct xfs_mount *mp = tp->t_mountp;
1998 struct xfs_agi *agi = agibp->b_addr;
1999 xfs_agino_t agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
2000 xfs_agino_t head_agino;
2001 short bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
2002 int error;
2003
2004 trace_xfs_iunlink_remove(ip);
2005
2006 /*
2007 * Get the index into the agi hash table for the list this inode will
2008 * go on. Make sure the head pointer isn't garbage.
2009 */
2010 head_agino = be32_to_cpu(agi->agi_unlinked[bucket_index]);
2011 if (!xfs_verify_agino(pag, head_agino)) {
2012 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
2013 agi, sizeof(*agi));
2014 return -EFSCORRUPTED;
2015 }
2016
2017 /*
2018 * Set our inode's next_unlinked pointer to NULL and then return
2019 * the old pointer value so that we can update whatever was previous
2020 * to us in the list to point to whatever was next in the list.
2021 */
2022 error = xfs_iunlink_log_inode(tp, ip, pag, NULLAGINO);
2023 if (error)
2024 return error;
2025
2026 /*
2027 * Update the prev pointer in the next inode to point back to previous
2028 * inode in the chain.
2029 */
2030 error = xfs_iunlink_update_backref(pag, ip->i_prev_unlinked,
2031 ip->i_next_unlinked);
2032 if (error)
2033 return error;
2034
2035 if (head_agino != agino) {
2036 struct xfs_inode *prev_ip;
2037
2038 prev_ip = xfs_iunlink_lookup(pag, ip->i_prev_unlinked);
2039 if (!prev_ip)
2040 return -EFSCORRUPTED;
2041
2042 error = xfs_iunlink_log_inode(tp, prev_ip, pag,
2043 ip->i_next_unlinked);
2044 prev_ip->i_next_unlinked = ip->i_next_unlinked;
2045 } else {
2046 /* Point the head of the list to the next unlinked inode. */
2047 error = xfs_iunlink_update_bucket(tp, pag, agibp, bucket_index,
2048 ip->i_next_unlinked);
2049 }
2050
2051 ip->i_next_unlinked = NULLAGINO;
2052 ip->i_prev_unlinked = NULLAGINO;
2053 return error;
2054}
2055
2056/*
2057 * Pull the on-disk inode from the AGI unlinked list.
2058 */
2059STATIC int
2060xfs_iunlink_remove(
2061 struct xfs_trans *tp,
2062 struct xfs_perag *pag,
2063 struct xfs_inode *ip)
2064{
2065 struct xfs_buf *agibp;
2066 int error;
2067
2068 trace_xfs_iunlink_remove(ip);
2069
2070 /* Get the agi buffer first. It ensures lock ordering on the list. */
2071 error = xfs_read_agi(pag, tp, &agibp);
2072 if (error)
2073 return error;
2074
2075 return xfs_iunlink_remove_inode(tp, pag, agibp, ip);
2076}
2077
2078/*
2079 * Look up the inode number specified and if it is not already marked XFS_ISTALE
2080 * mark it stale. We should only find clean inodes in this lookup that aren't
2081 * already stale.
2082 */
2083static void
2084xfs_ifree_mark_inode_stale(
2085 struct xfs_perag *pag,
2086 struct xfs_inode *free_ip,
2087 xfs_ino_t inum)
2088{
2089 struct xfs_mount *mp = pag->pag_mount;
2090 struct xfs_inode_log_item *iip;
2091 struct xfs_inode *ip;
2092
2093retry:
2094 rcu_read_lock();
2095 ip = radix_tree_lookup(&pag->pag_ici_root, XFS_INO_TO_AGINO(mp, inum));
2096
2097 /* Inode not in memory, nothing to do */
2098 if (!ip) {
2099 rcu_read_unlock();
2100 return;
2101 }
2102
2103 /*
2104 * because this is an RCU protected lookup, we could find a recently
2105 * freed or even reallocated inode during the lookup. We need to check
2106 * under the i_flags_lock for a valid inode here. Skip it if it is not
2107 * valid, the wrong inode or stale.
2108 */
2109 spin_lock(&ip->i_flags_lock);
2110 if (ip->i_ino != inum || __xfs_iflags_test(ip, XFS_ISTALE))
2111 goto out_iflags_unlock;
2112
2113 /*
2114 * Don't try to lock/unlock the current inode, but we _cannot_ skip the
2115 * other inodes that we did not find in the list attached to the buffer
2116 * and are not already marked stale. If we can't lock it, back off and
2117 * retry.
2118 */
2119 if (ip != free_ip) {
2120 if (!xfs_ilock_nowait(ip, XFS_ILOCK_EXCL)) {
2121 spin_unlock(&ip->i_flags_lock);
2122 rcu_read_unlock();
2123 delay(1);
2124 goto retry;
2125 }
2126 }
2127 ip->i_flags |= XFS_ISTALE;
2128
2129 /*
2130 * If the inode is flushing, it is already attached to the buffer. All
2131 * we needed to do here is mark the inode stale so buffer IO completion
2132 * will remove it from the AIL.
2133 */
2134 iip = ip->i_itemp;
2135 if (__xfs_iflags_test(ip, XFS_IFLUSHING)) {
2136 ASSERT(!list_empty(&iip->ili_item.li_bio_list));
2137 ASSERT(iip->ili_last_fields);
2138 goto out_iunlock;
2139 }
2140
2141 /*
2142 * Inodes not attached to the buffer can be released immediately.
2143 * Everything else has to go through xfs_iflush_abort() on journal
2144 * commit as the flock synchronises removal of the inode from the
2145 * cluster buffer against inode reclaim.
2146 */
2147 if (!iip || list_empty(&iip->ili_item.li_bio_list))
2148 goto out_iunlock;
2149
2150 __xfs_iflags_set(ip, XFS_IFLUSHING);
2151 spin_unlock(&ip->i_flags_lock);
2152 rcu_read_unlock();
2153
2154 /* we have a dirty inode in memory that has not yet been flushed. */
2155 spin_lock(&iip->ili_lock);
2156 iip->ili_last_fields = iip->ili_fields;
2157 iip->ili_fields = 0;
2158 iip->ili_fsync_fields = 0;
2159 spin_unlock(&iip->ili_lock);
2160 ASSERT(iip->ili_last_fields);
2161
2162 if (ip != free_ip)
2163 xfs_iunlock(ip, XFS_ILOCK_EXCL);
2164 return;
2165
2166out_iunlock:
2167 if (ip != free_ip)
2168 xfs_iunlock(ip, XFS_ILOCK_EXCL);
2169out_iflags_unlock:
2170 spin_unlock(&ip->i_flags_lock);
2171 rcu_read_unlock();
2172}
2173
2174/*
2175 * A big issue when freeing the inode cluster is that we _cannot_ skip any
2176 * inodes that are in memory - they all must be marked stale and attached to
2177 * the cluster buffer.
2178 */
2179static int
2180xfs_ifree_cluster(
2181 struct xfs_trans *tp,
2182 struct xfs_perag *pag,
2183 struct xfs_inode *free_ip,
2184 struct xfs_icluster *xic)
2185{
2186 struct xfs_mount *mp = free_ip->i_mount;
2187 struct xfs_ino_geometry *igeo = M_IGEO(mp);
2188 struct xfs_buf *bp;
2189 xfs_daddr_t blkno;
2190 xfs_ino_t inum = xic->first_ino;
2191 int nbufs;
2192 int i, j;
2193 int ioffset;
2194 int error;
2195
2196 nbufs = igeo->ialloc_blks / igeo->blocks_per_cluster;
2197
2198 for (j = 0; j < nbufs; j++, inum += igeo->inodes_per_cluster) {
2199 /*
2200 * The allocation bitmap tells us which inodes of the chunk were
2201 * physically allocated. Skip the cluster if an inode falls into
2202 * a sparse region.
2203 */
2204 ioffset = inum - xic->first_ino;
2205 if ((xic->alloc & XFS_INOBT_MASK(ioffset)) == 0) {
2206 ASSERT(ioffset % igeo->inodes_per_cluster == 0);
2207 continue;
2208 }
2209
2210 blkno = XFS_AGB_TO_DADDR(mp, XFS_INO_TO_AGNO(mp, inum),
2211 XFS_INO_TO_AGBNO(mp, inum));
2212
2213 /*
2214 * We obtain and lock the backing buffer first in the process
2215 * here to ensure dirty inodes attached to the buffer remain in
2216 * the flushing state while we mark them stale.
2217 *
2218 * If we scan the in-memory inodes first, then buffer IO can
2219 * complete before we get a lock on it, and hence we may fail
2220 * to mark all the active inodes on the buffer stale.
2221 */
2222 error = xfs_trans_get_buf(tp, mp->m_ddev_targp, blkno,
2223 mp->m_bsize * igeo->blocks_per_cluster,
2224 XBF_UNMAPPED, &bp);
2225 if (error)
2226 return error;
2227
2228 /*
2229 * This buffer may not have been correctly initialised as we
2230 * didn't read it from disk. That's not important because we are
2231 * only using to mark the buffer as stale in the log, and to
2232 * attach stale cached inodes on it. That means it will never be
2233 * dispatched for IO. If it is, we want to know about it, and we
2234 * want it to fail. We can acheive this by adding a write
2235 * verifier to the buffer.
2236 */
2237 bp->b_ops = &xfs_inode_buf_ops;
2238
2239 /*
2240 * Now we need to set all the cached clean inodes as XFS_ISTALE,
2241 * too. This requires lookups, and will skip inodes that we've
2242 * already marked XFS_ISTALE.
2243 */
2244 for (i = 0; i < igeo->inodes_per_cluster; i++)
2245 xfs_ifree_mark_inode_stale(pag, free_ip, inum + i);
2246
2247 xfs_trans_stale_inode_buf(tp, bp);
2248 xfs_trans_binval(tp, bp);
2249 }
2250 return 0;
2251}
2252
2253/*
2254 * This is called to return an inode to the inode free list. The inode should
2255 * already be truncated to 0 length and have no pages associated with it. This
2256 * routine also assumes that the inode is already a part of the transaction.
2257 *
2258 * The on-disk copy of the inode will have been added to the list of unlinked
2259 * inodes in the AGI. We need to remove the inode from that list atomically with
2260 * respect to freeing it here.
2261 */
2262int
2263xfs_ifree(
2264 struct xfs_trans *tp,
2265 struct xfs_inode *ip)
2266{
2267 struct xfs_mount *mp = ip->i_mount;
2268 struct xfs_perag *pag;
2269 struct xfs_icluster xic = { 0 };
2270 struct xfs_inode_log_item *iip = ip->i_itemp;
2271 int error;
2272
2273 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
2274 ASSERT(VFS_I(ip)->i_nlink == 0);
2275 ASSERT(ip->i_df.if_nextents == 0);
2276 ASSERT(ip->i_disk_size == 0 || !S_ISREG(VFS_I(ip)->i_mode));
2277 ASSERT(ip->i_nblocks == 0);
2278
2279 pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));
2280
2281 /*
2282 * Free the inode first so that we guarantee that the AGI lock is going
2283 * to be taken before we remove the inode from the unlinked list. This
2284 * makes the AGI lock -> unlinked list modification order the same as
2285 * used in O_TMPFILE creation.
2286 */
2287 error = xfs_difree(tp, pag, ip->i_ino, &xic);
2288 if (error)
2289 goto out;
2290
2291 error = xfs_iunlink_remove(tp, pag, ip);
2292 if (error)
2293 goto out;
2294
2295 /*
2296 * Free any local-format data sitting around before we reset the
2297 * data fork to extents format. Note that the attr fork data has
2298 * already been freed by xfs_attr_inactive.
2299 */
2300 if (ip->i_df.if_format == XFS_DINODE_FMT_LOCAL) {
2301 kmem_free(ip->i_df.if_u1.if_data);
2302 ip->i_df.if_u1.if_data = NULL;
2303 ip->i_df.if_bytes = 0;
2304 }
2305
2306 VFS_I(ip)->i_mode = 0; /* mark incore inode as free */
2307 ip->i_diflags = 0;
2308 ip->i_diflags2 = mp->m_ino_geo.new_diflags2;
2309 ip->i_forkoff = 0; /* mark the attr fork not in use */
2310 ip->i_df.if_format = XFS_DINODE_FMT_EXTENTS;
2311 if (xfs_iflags_test(ip, XFS_IPRESERVE_DM_FIELDS))
2312 xfs_iflags_clear(ip, XFS_IPRESERVE_DM_FIELDS);
2313
2314 /* Don't attempt to replay owner changes for a deleted inode */
2315 spin_lock(&iip->ili_lock);
2316 iip->ili_fields &= ~(XFS_ILOG_AOWNER | XFS_ILOG_DOWNER);
2317 spin_unlock(&iip->ili_lock);
2318
2319 /*
2320 * Bump the generation count so no one will be confused
2321 * by reincarnations of this inode.
2322 */
2323 VFS_I(ip)->i_generation++;
2324 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
2325
2326 if (xic.deleted)
2327 error = xfs_ifree_cluster(tp, pag, ip, &xic);
2328out:
2329 xfs_perag_put(pag);
2330 return error;
2331}
2332
2333/*
2334 * This is called to unpin an inode. The caller must have the inode locked
2335 * in at least shared mode so that the buffer cannot be subsequently pinned
2336 * once someone is waiting for it to be unpinned.
2337 */
2338static void
2339xfs_iunpin(
2340 struct xfs_inode *ip)
2341{
2342 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
2343
2344 trace_xfs_inode_unpin_nowait(ip, _RET_IP_);
2345
2346 /* Give the log a push to start the unpinning I/O */
2347 xfs_log_force_seq(ip->i_mount, ip->i_itemp->ili_commit_seq, 0, NULL);
2348
2349}
2350
2351static void
2352__xfs_iunpin_wait(
2353 struct xfs_inode *ip)
2354{
2355 wait_queue_head_t *wq = bit_waitqueue(&ip->i_flags, __XFS_IPINNED_BIT);
2356 DEFINE_WAIT_BIT(wait, &ip->i_flags, __XFS_IPINNED_BIT);
2357
2358 xfs_iunpin(ip);
2359
2360 do {
2361 prepare_to_wait(wq, &wait.wq_entry, TASK_UNINTERRUPTIBLE);
2362 if (xfs_ipincount(ip))
2363 io_schedule();
2364 } while (xfs_ipincount(ip));
2365 finish_wait(wq, &wait.wq_entry);
2366}
2367
2368void
2369xfs_iunpin_wait(
2370 struct xfs_inode *ip)
2371{
2372 if (xfs_ipincount(ip))
2373 __xfs_iunpin_wait(ip);
2374}
2375
2376/*
2377 * Removing an inode from the namespace involves removing the directory entry
2378 * and dropping the link count on the inode. Removing the directory entry can
2379 * result in locking an AGF (directory blocks were freed) and removing a link
2380 * count can result in placing the inode on an unlinked list which results in
2381 * locking an AGI.
2382 *
2383 * The big problem here is that we have an ordering constraint on AGF and AGI
2384 * locking - inode allocation locks the AGI, then can allocate a new extent for
2385 * new inodes, locking the AGF after the AGI. Similarly, freeing the inode
2386 * removes the inode from the unlinked list, requiring that we lock the AGI
2387 * first, and then freeing the inode can result in an inode chunk being freed
2388 * and hence freeing disk space requiring that we lock an AGF.
2389 *
2390 * Hence the ordering that is imposed by other parts of the code is AGI before
2391 * AGF. This means we cannot remove the directory entry before we drop the inode
2392 * reference count and put it on the unlinked list as this results in a lock
2393 * order of AGF then AGI, and this can deadlock against inode allocation and
2394 * freeing. Therefore we must drop the link counts before we remove the
2395 * directory entry.
2396 *
2397 * This is still safe from a transactional point of view - it is not until we
2398 * get to xfs_defer_finish() that we have the possibility of multiple
2399 * transactions in this operation. Hence as long as we remove the directory
2400 * entry and drop the link count in the first transaction of the remove
2401 * operation, there are no transactional constraints on the ordering here.
2402 */
2403int
2404xfs_remove(
2405 xfs_inode_t *dp,
2406 struct xfs_name *name,
2407 xfs_inode_t *ip)
2408{
2409 xfs_mount_t *mp = dp->i_mount;
2410 xfs_trans_t *tp = NULL;
2411 int is_dir = S_ISDIR(VFS_I(ip)->i_mode);
2412 int dontcare;
2413 int error = 0;
2414 uint resblks;
2415
2416 trace_xfs_remove(dp, name);
2417
2418 if (xfs_is_shutdown(mp))
2419 return -EIO;
2420
2421 error = xfs_qm_dqattach(dp);
2422 if (error)
2423 goto std_return;
2424
2425 error = xfs_qm_dqattach(ip);
2426 if (error)
2427 goto std_return;
2428
2429 /*
2430 * We try to get the real space reservation first, allowing for
2431 * directory btree deletion(s) implying possible bmap insert(s). If we
2432 * can't get the space reservation then we use 0 instead, and avoid the
2433 * bmap btree insert(s) in the directory code by, if the bmap insert
2434 * tries to happen, instead trimming the LAST block from the directory.
2435 *
2436 * Ignore EDQUOT and ENOSPC being returned via nospace_error because
2437 * the directory code can handle a reservationless update and we don't
2438 * want to prevent a user from trying to free space by deleting things.
2439 */
2440 resblks = XFS_REMOVE_SPACE_RES(mp);
2441 error = xfs_trans_alloc_dir(dp, &M_RES(mp)->tr_remove, ip, &resblks,
2442 &tp, &dontcare);
2443 if (error) {
2444 ASSERT(error != -ENOSPC);
2445 goto std_return;
2446 }
2447
2448 /*
2449 * If we're removing a directory perform some additional validation.
2450 */
2451 if (is_dir) {
2452 ASSERT(VFS_I(ip)->i_nlink >= 2);
2453 if (VFS_I(ip)->i_nlink != 2) {
2454 error = -ENOTEMPTY;
2455 goto out_trans_cancel;
2456 }
2457 if (!xfs_dir_isempty(ip)) {
2458 error = -ENOTEMPTY;
2459 goto out_trans_cancel;
2460 }
2461
2462 /* Drop the link from ip's "..". */
2463 error = xfs_droplink(tp, dp);
2464 if (error)
2465 goto out_trans_cancel;
2466
2467 /* Drop the "." link from ip to self. */
2468 error = xfs_droplink(tp, ip);
2469 if (error)
2470 goto out_trans_cancel;
2471
2472 /*
2473 * Point the unlinked child directory's ".." entry to the root
2474 * directory to eliminate back-references to inodes that may
2475 * get freed before the child directory is closed. If the fs
2476 * gets shrunk, this can lead to dirent inode validation errors.
2477 */
2478 if (dp->i_ino != tp->t_mountp->m_sb.sb_rootino) {
2479 error = xfs_dir_replace(tp, ip, &xfs_name_dotdot,
2480 tp->t_mountp->m_sb.sb_rootino, 0);
2481 if (error)
2482 goto out_trans_cancel;
2483 }
2484 } else {
2485 /*
2486 * When removing a non-directory we need to log the parent
2487 * inode here. For a directory this is done implicitly
2488 * by the xfs_droplink call for the ".." entry.
2489 */
2490 xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
2491 }
2492 xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2493
2494 /* Drop the link from dp to ip. */
2495 error = xfs_droplink(tp, ip);
2496 if (error)
2497 goto out_trans_cancel;
2498
2499 error = xfs_dir_removename(tp, dp, name, ip->i_ino, resblks);
2500 if (error) {
2501 ASSERT(error != -ENOENT);
2502 goto out_trans_cancel;
2503 }
2504
2505 /*
2506 * If this is a synchronous mount, make sure that the
2507 * remove transaction goes to disk before returning to
2508 * the user.
2509 */
2510 if (xfs_has_wsync(mp) || xfs_has_dirsync(mp))
2511 xfs_trans_set_sync(tp);
2512
2513 error = xfs_trans_commit(tp);
2514 if (error)
2515 goto std_return;
2516
2517 if (is_dir && xfs_inode_is_filestream(ip))
2518 xfs_filestream_deassociate(ip);
2519
2520 return 0;
2521
2522 out_trans_cancel:
2523 xfs_trans_cancel(tp);
2524 std_return:
2525 return error;
2526}
2527
2528/*
2529 * Enter all inodes for a rename transaction into a sorted array.
2530 */
2531#define __XFS_SORT_INODES 5
2532STATIC void
2533xfs_sort_for_rename(
2534 struct xfs_inode *dp1, /* in: old (source) directory inode */
2535 struct xfs_inode *dp2, /* in: new (target) directory inode */
2536 struct xfs_inode *ip1, /* in: inode of old entry */
2537 struct xfs_inode *ip2, /* in: inode of new entry */
2538 struct xfs_inode *wip, /* in: whiteout inode */
2539 struct xfs_inode **i_tab,/* out: sorted array of inodes */
2540 int *num_inodes) /* in/out: inodes in array */
2541{
2542 int i, j;
2543
2544 ASSERT(*num_inodes == __XFS_SORT_INODES);
2545 memset(i_tab, 0, *num_inodes * sizeof(struct xfs_inode *));
2546
2547 /*
2548 * i_tab contains a list of pointers to inodes. We initialize
2549 * the table here & we'll sort it. We will then use it to
2550 * order the acquisition of the inode locks.
2551 *
2552 * Note that the table may contain duplicates. e.g., dp1 == dp2.
2553 */
2554 i = 0;
2555 i_tab[i++] = dp1;
2556 i_tab[i++] = dp2;
2557 i_tab[i++] = ip1;
2558 if (ip2)
2559 i_tab[i++] = ip2;
2560 if (wip)
2561 i_tab[i++] = wip;
2562 *num_inodes = i;
2563
2564 /*
2565 * Sort the elements via bubble sort. (Remember, there are at
2566 * most 5 elements to sort, so this is adequate.)
2567 */
2568 for (i = 0; i < *num_inodes; i++) {
2569 for (j = 1; j < *num_inodes; j++) {
2570 if (i_tab[j]->i_ino < i_tab[j-1]->i_ino) {
2571 struct xfs_inode *temp = i_tab[j];
2572 i_tab[j] = i_tab[j-1];
2573 i_tab[j-1] = temp;
2574 }
2575 }
2576 }
2577}
2578
2579static int
2580xfs_finish_rename(
2581 struct xfs_trans *tp)
2582{
2583 /*
2584 * If this is a synchronous mount, make sure that the rename transaction
2585 * goes to disk before returning to the user.
2586 */
2587 if (xfs_has_wsync(tp->t_mountp) || xfs_has_dirsync(tp->t_mountp))
2588 xfs_trans_set_sync(tp);
2589
2590 return xfs_trans_commit(tp);
2591}
2592
2593/*
2594 * xfs_cross_rename()
2595 *
2596 * responsible for handling RENAME_EXCHANGE flag in renameat2() syscall
2597 */
2598STATIC int
2599xfs_cross_rename(
2600 struct xfs_trans *tp,
2601 struct xfs_inode *dp1,
2602 struct xfs_name *name1,
2603 struct xfs_inode *ip1,
2604 struct xfs_inode *dp2,
2605 struct xfs_name *name2,
2606 struct xfs_inode *ip2,
2607 int spaceres)
2608{
2609 int error = 0;
2610 int ip1_flags = 0;
2611 int ip2_flags = 0;
2612 int dp2_flags = 0;
2613
2614 /* Swap inode number for dirent in first parent */
2615 error = xfs_dir_replace(tp, dp1, name1, ip2->i_ino, spaceres);
2616 if (error)
2617 goto out_trans_abort;
2618
2619 /* Swap inode number for dirent in second parent */
2620 error = xfs_dir_replace(tp, dp2, name2, ip1->i_ino, spaceres);
2621 if (error)
2622 goto out_trans_abort;
2623
2624 /*
2625 * If we're renaming one or more directories across different parents,
2626 * update the respective ".." entries (and link counts) to match the new
2627 * parents.
2628 */
2629 if (dp1 != dp2) {
2630 dp2_flags = XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
2631
2632 if (S_ISDIR(VFS_I(ip2)->i_mode)) {
2633 error = xfs_dir_replace(tp, ip2, &xfs_name_dotdot,
2634 dp1->i_ino, spaceres);
2635 if (error)
2636 goto out_trans_abort;
2637
2638 /* transfer ip2 ".." reference to dp1 */
2639 if (!S_ISDIR(VFS_I(ip1)->i_mode)) {
2640 error = xfs_droplink(tp, dp2);
2641 if (error)
2642 goto out_trans_abort;
2643 xfs_bumplink(tp, dp1);
2644 }
2645
2646 /*
2647 * Although ip1 isn't changed here, userspace needs
2648 * to be warned about the change, so that applications
2649 * relying on it (like backup ones), will properly
2650 * notify the change
2651 */
2652 ip1_flags |= XFS_ICHGTIME_CHG;
2653 ip2_flags |= XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
2654 }
2655
2656 if (S_ISDIR(VFS_I(ip1)->i_mode)) {
2657 error = xfs_dir_replace(tp, ip1, &xfs_name_dotdot,
2658 dp2->i_ino, spaceres);
2659 if (error)
2660 goto out_trans_abort;
2661
2662 /* transfer ip1 ".." reference to dp2 */
2663 if (!S_ISDIR(VFS_I(ip2)->i_mode)) {
2664 error = xfs_droplink(tp, dp1);
2665 if (error)
2666 goto out_trans_abort;
2667 xfs_bumplink(tp, dp2);
2668 }
2669
2670 /*
2671 * Although ip2 isn't changed here, userspace needs
2672 * to be warned about the change, so that applications
2673 * relying on it (like backup ones), will properly
2674 * notify the change
2675 */
2676 ip1_flags |= XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
2677 ip2_flags |= XFS_ICHGTIME_CHG;
2678 }
2679 }
2680
2681 if (ip1_flags) {
2682 xfs_trans_ichgtime(tp, ip1, ip1_flags);
2683 xfs_trans_log_inode(tp, ip1, XFS_ILOG_CORE);
2684 }
2685 if (ip2_flags) {
2686 xfs_trans_ichgtime(tp, ip2, ip2_flags);
2687 xfs_trans_log_inode(tp, ip2, XFS_ILOG_CORE);
2688 }
2689 if (dp2_flags) {
2690 xfs_trans_ichgtime(tp, dp2, dp2_flags);
2691 xfs_trans_log_inode(tp, dp2, XFS_ILOG_CORE);
2692 }
2693 xfs_trans_ichgtime(tp, dp1, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2694 xfs_trans_log_inode(tp, dp1, XFS_ILOG_CORE);
2695 return xfs_finish_rename(tp);
2696
2697out_trans_abort:
2698 xfs_trans_cancel(tp);
2699 return error;
2700}
2701
2702/*
2703 * xfs_rename_alloc_whiteout()
2704 *
2705 * Return a referenced, unlinked, unlocked inode that can be used as a
2706 * whiteout in a rename transaction. We use a tmpfile inode here so that if we
2707 * crash between allocating the inode and linking it into the rename transaction
2708 * recovery will free the inode and we won't leak it.
2709 */
2710static int
2711xfs_rename_alloc_whiteout(
2712 struct user_namespace *mnt_userns,
2713 struct xfs_name *src_name,
2714 struct xfs_inode *dp,
2715 struct xfs_inode **wip)
2716{
2717 struct xfs_inode *tmpfile;
2718 struct qstr name;
2719 int error;
2720
2721 error = xfs_create_tmpfile(mnt_userns, dp, S_IFCHR | WHITEOUT_MODE,
2722 &tmpfile);
2723 if (error)
2724 return error;
2725
2726 name.name = src_name->name;
2727 name.len = src_name->len;
2728 error = xfs_inode_init_security(VFS_I(tmpfile), VFS_I(dp), &name);
2729 if (error) {
2730 xfs_finish_inode_setup(tmpfile);
2731 xfs_irele(tmpfile);
2732 return error;
2733 }
2734
2735 /*
2736 * Prepare the tmpfile inode as if it were created through the VFS.
2737 * Complete the inode setup and flag it as linkable. nlink is already
2738 * zero, so we can skip the drop_nlink.
2739 */
2740 xfs_setup_iops(tmpfile);
2741 xfs_finish_inode_setup(tmpfile);
2742 VFS_I(tmpfile)->i_state |= I_LINKABLE;
2743
2744 *wip = tmpfile;
2745 return 0;
2746}
2747
2748/*
2749 * xfs_rename
2750 */
2751int
2752xfs_rename(
2753 struct user_namespace *mnt_userns,
2754 struct xfs_inode *src_dp,
2755 struct xfs_name *src_name,
2756 struct xfs_inode *src_ip,
2757 struct xfs_inode *target_dp,
2758 struct xfs_name *target_name,
2759 struct xfs_inode *target_ip,
2760 unsigned int flags)
2761{
2762 struct xfs_mount *mp = src_dp->i_mount;
2763 struct xfs_trans *tp;
2764 struct xfs_inode *wip = NULL; /* whiteout inode */
2765 struct xfs_inode *inodes[__XFS_SORT_INODES];
2766 int i;
2767 int num_inodes = __XFS_SORT_INODES;
2768 bool new_parent = (src_dp != target_dp);
2769 bool src_is_directory = S_ISDIR(VFS_I(src_ip)->i_mode);
2770 int spaceres;
2771 bool retried = false;
2772 int error, nospace_error = 0;
2773
2774 trace_xfs_rename(src_dp, target_dp, src_name, target_name);
2775
2776 if ((flags & RENAME_EXCHANGE) && !target_ip)
2777 return -EINVAL;
2778
2779 /*
2780 * If we are doing a whiteout operation, allocate the whiteout inode
2781 * we will be placing at the target and ensure the type is set
2782 * appropriately.
2783 */
2784 if (flags & RENAME_WHITEOUT) {
2785 error = xfs_rename_alloc_whiteout(mnt_userns, src_name,
2786 target_dp, &wip);
2787 if (error)
2788 return error;
2789
2790 /* setup target dirent info as whiteout */
2791 src_name->type = XFS_DIR3_FT_CHRDEV;
2792 }
2793
2794 xfs_sort_for_rename(src_dp, target_dp, src_ip, target_ip, wip,
2795 inodes, &num_inodes);
2796
2797retry:
2798 nospace_error = 0;
2799 spaceres = XFS_RENAME_SPACE_RES(mp, target_name->len);
2800 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_rename, spaceres, 0, 0, &tp);
2801 if (error == -ENOSPC) {
2802 nospace_error = error;
2803 spaceres = 0;
2804 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_rename, 0, 0, 0,
2805 &tp);
2806 }
2807 if (error)
2808 goto out_release_wip;
2809
2810 /*
2811 * Attach the dquots to the inodes
2812 */
2813 error = xfs_qm_vop_rename_dqattach(inodes);
2814 if (error)
2815 goto out_trans_cancel;
2816
2817 /*
2818 * Lock all the participating inodes. Depending upon whether
2819 * the target_name exists in the target directory, and
2820 * whether the target directory is the same as the source
2821 * directory, we can lock from 2 to 5 inodes.
2822 */
2823 xfs_lock_inodes(inodes, num_inodes, XFS_ILOCK_EXCL);
2824
2825 /*
2826 * Join all the inodes to the transaction. From this point on,
2827 * we can rely on either trans_commit or trans_cancel to unlock
2828 * them.
2829 */
2830 xfs_trans_ijoin(tp, src_dp, XFS_ILOCK_EXCL);
2831 if (new_parent)
2832 xfs_trans_ijoin(tp, target_dp, XFS_ILOCK_EXCL);
2833 xfs_trans_ijoin(tp, src_ip, XFS_ILOCK_EXCL);
2834 if (target_ip)
2835 xfs_trans_ijoin(tp, target_ip, XFS_ILOCK_EXCL);
2836 if (wip)
2837 xfs_trans_ijoin(tp, wip, XFS_ILOCK_EXCL);
2838
2839 /*
2840 * If we are using project inheritance, we only allow renames
2841 * into our tree when the project IDs are the same; else the
2842 * tree quota mechanism would be circumvented.
2843 */
2844 if (unlikely((target_dp->i_diflags & XFS_DIFLAG_PROJINHERIT) &&
2845 target_dp->i_projid != src_ip->i_projid)) {
2846 error = -EXDEV;
2847 goto out_trans_cancel;
2848 }
2849
2850 /* RENAME_EXCHANGE is unique from here on. */
2851 if (flags & RENAME_EXCHANGE)
2852 return xfs_cross_rename(tp, src_dp, src_name, src_ip,
2853 target_dp, target_name, target_ip,
2854 spaceres);
2855
2856 /*
2857 * Try to reserve quota to handle an expansion of the target directory.
2858 * We'll allow the rename to continue in reservationless mode if we hit
2859 * a space usage constraint. If we trigger reservationless mode, save
2860 * the errno if there isn't any free space in the target directory.
2861 */
2862 if (spaceres != 0) {
2863 error = xfs_trans_reserve_quota_nblks(tp, target_dp, spaceres,
2864 0, false);
2865 if (error == -EDQUOT || error == -ENOSPC) {
2866 if (!retried) {
2867 xfs_trans_cancel(tp);
2868 xfs_blockgc_free_quota(target_dp, 0);
2869 retried = true;
2870 goto retry;
2871 }
2872
2873 nospace_error = error;
2874 spaceres = 0;
2875 error = 0;
2876 }
2877 if (error)
2878 goto out_trans_cancel;
2879 }
2880
2881 /*
2882 * Check for expected errors before we dirty the transaction
2883 * so we can return an error without a transaction abort.
2884 */
2885 if (target_ip == NULL) {
2886 /*
2887 * If there's no space reservation, check the entry will
2888 * fit before actually inserting it.
2889 */
2890 if (!spaceres) {
2891 error = xfs_dir_canenter(tp, target_dp, target_name);
2892 if (error)
2893 goto out_trans_cancel;
2894 }
2895 } else {
2896 /*
2897 * If target exists and it's a directory, check that whether
2898 * it can be destroyed.
2899 */
2900 if (S_ISDIR(VFS_I(target_ip)->i_mode) &&
2901 (!xfs_dir_isempty(target_ip) ||
2902 (VFS_I(target_ip)->i_nlink > 2))) {
2903 error = -EEXIST;
2904 goto out_trans_cancel;
2905 }
2906 }
2907
2908 /*
2909 * Lock the AGI buffers we need to handle bumping the nlink of the
2910 * whiteout inode off the unlinked list and to handle dropping the
2911 * nlink of the target inode. Per locking order rules, do this in
2912 * increasing AG order and before directory block allocation tries to
2913 * grab AGFs because we grab AGIs before AGFs.
2914 *
2915 * The (vfs) caller must ensure that if src is a directory then
2916 * target_ip is either null or an empty directory.
2917 */
2918 for (i = 0; i < num_inodes && inodes[i] != NULL; i++) {
2919 if (inodes[i] == wip ||
2920 (inodes[i] == target_ip &&
2921 (VFS_I(target_ip)->i_nlink == 1 || src_is_directory))) {
2922 struct xfs_perag *pag;
2923 struct xfs_buf *bp;
2924
2925 pag = xfs_perag_get(mp,
2926 XFS_INO_TO_AGNO(mp, inodes[i]->i_ino));
2927 error = xfs_read_agi(pag, tp, &bp);
2928 xfs_perag_put(pag);
2929 if (error)
2930 goto out_trans_cancel;
2931 }
2932 }
2933
2934 /*
2935 * Directory entry creation below may acquire the AGF. Remove
2936 * the whiteout from the unlinked list first to preserve correct
2937 * AGI/AGF locking order. This dirties the transaction so failures
2938 * after this point will abort and log recovery will clean up the
2939 * mess.
2940 *
2941 * For whiteouts, we need to bump the link count on the whiteout
2942 * inode. After this point, we have a real link, clear the tmpfile
2943 * state flag from the inode so it doesn't accidentally get misused
2944 * in future.
2945 */
2946 if (wip) {
2947 struct xfs_perag *pag;
2948
2949 ASSERT(VFS_I(wip)->i_nlink == 0);
2950
2951 pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, wip->i_ino));
2952 error = xfs_iunlink_remove(tp, pag, wip);
2953 xfs_perag_put(pag);
2954 if (error)
2955 goto out_trans_cancel;
2956
2957 xfs_bumplink(tp, wip);
2958 VFS_I(wip)->i_state &= ~I_LINKABLE;
2959 }
2960
2961 /*
2962 * Set up the target.
2963 */
2964 if (target_ip == NULL) {
2965 /*
2966 * If target does not exist and the rename crosses
2967 * directories, adjust the target directory link count
2968 * to account for the ".." reference from the new entry.
2969 */
2970 error = xfs_dir_createname(tp, target_dp, target_name,
2971 src_ip->i_ino, spaceres);
2972 if (error)
2973 goto out_trans_cancel;
2974
2975 xfs_trans_ichgtime(tp, target_dp,
2976 XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2977
2978 if (new_parent && src_is_directory) {
2979 xfs_bumplink(tp, target_dp);
2980 }
2981 } else { /* target_ip != NULL */
2982 /*
2983 * Link the source inode under the target name.
2984 * If the source inode is a directory and we are moving
2985 * it across directories, its ".." entry will be
2986 * inconsistent until we replace that down below.
2987 *
2988 * In case there is already an entry with the same
2989 * name at the destination directory, remove it first.
2990 */
2991 error = xfs_dir_replace(tp, target_dp, target_name,
2992 src_ip->i_ino, spaceres);
2993 if (error)
2994 goto out_trans_cancel;
2995
2996 xfs_trans_ichgtime(tp, target_dp,
2997 XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2998
2999 /*
3000 * Decrement the link count on the target since the target
3001 * dir no longer points to it.
3002 */
3003 error = xfs_droplink(tp, target_ip);
3004 if (error)
3005 goto out_trans_cancel;
3006
3007 if (src_is_directory) {
3008 /*
3009 * Drop the link from the old "." entry.
3010 */
3011 error = xfs_droplink(tp, target_ip);
3012 if (error)
3013 goto out_trans_cancel;
3014 }
3015 } /* target_ip != NULL */
3016
3017 /*
3018 * Remove the source.
3019 */
3020 if (new_parent && src_is_directory) {
3021 /*
3022 * Rewrite the ".." entry to point to the new
3023 * directory.
3024 */
3025 error = xfs_dir_replace(tp, src_ip, &xfs_name_dotdot,
3026 target_dp->i_ino, spaceres);
3027 ASSERT(error != -EEXIST);
3028 if (error)
3029 goto out_trans_cancel;
3030 }
3031
3032 /*
3033 * We always want to hit the ctime on the source inode.
3034 *
3035 * This isn't strictly required by the standards since the source
3036 * inode isn't really being changed, but old unix file systems did
3037 * it and some incremental backup programs won't work without it.
3038 */
3039 xfs_trans_ichgtime(tp, src_ip, XFS_ICHGTIME_CHG);
3040 xfs_trans_log_inode(tp, src_ip, XFS_ILOG_CORE);
3041
3042 /*
3043 * Adjust the link count on src_dp. This is necessary when
3044 * renaming a directory, either within one parent when
3045 * the target existed, or across two parent directories.
3046 */
3047 if (src_is_directory && (new_parent || target_ip != NULL)) {
3048
3049 /*
3050 * Decrement link count on src_directory since the
3051 * entry that's moved no longer points to it.
3052 */
3053 error = xfs_droplink(tp, src_dp);
3054 if (error)
3055 goto out_trans_cancel;
3056 }
3057
3058 /*
3059 * For whiteouts, we only need to update the source dirent with the
3060 * inode number of the whiteout inode rather than removing it
3061 * altogether.
3062 */
3063 if (wip)
3064 error = xfs_dir_replace(tp, src_dp, src_name, wip->i_ino,
3065 spaceres);
3066 else
3067 error = xfs_dir_removename(tp, src_dp, src_name, src_ip->i_ino,
3068 spaceres);
3069
3070 if (error)
3071 goto out_trans_cancel;
3072
3073 xfs_trans_ichgtime(tp, src_dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
3074 xfs_trans_log_inode(tp, src_dp, XFS_ILOG_CORE);
3075 if (new_parent)
3076 xfs_trans_log_inode(tp, target_dp, XFS_ILOG_CORE);
3077
3078 error = xfs_finish_rename(tp);
3079 if (wip)
3080 xfs_irele(wip);
3081 return error;
3082
3083out_trans_cancel:
3084 xfs_trans_cancel(tp);
3085out_release_wip:
3086 if (wip)
3087 xfs_irele(wip);
3088 if (error == -ENOSPC && nospace_error)
3089 error = nospace_error;
3090 return error;
3091}
3092
3093static int
3094xfs_iflush(
3095 struct xfs_inode *ip,
3096 struct xfs_buf *bp)
3097{
3098 struct xfs_inode_log_item *iip = ip->i_itemp;
3099 struct xfs_dinode *dip;
3100 struct xfs_mount *mp = ip->i_mount;
3101 int error;
3102
3103 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
3104 ASSERT(xfs_iflags_test(ip, XFS_IFLUSHING));
3105 ASSERT(ip->i_df.if_format != XFS_DINODE_FMT_BTREE ||
3106 ip->i_df.if_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK));
3107 ASSERT(iip->ili_item.li_buf == bp);
3108
3109 dip = xfs_buf_offset(bp, ip->i_imap.im_boffset);
3110
3111 /*
3112 * We don't flush the inode if any of the following checks fail, but we
3113 * do still update the log item and attach to the backing buffer as if
3114 * the flush happened. This is a formality to facilitate predictable
3115 * error handling as the caller will shutdown and fail the buffer.
3116 */
3117 error = -EFSCORRUPTED;
3118 if (XFS_TEST_ERROR(dip->di_magic != cpu_to_be16(XFS_DINODE_MAGIC),
3119 mp, XFS_ERRTAG_IFLUSH_1)) {
3120 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3121 "%s: Bad inode %llu magic number 0x%x, ptr "PTR_FMT,
3122 __func__, ip->i_ino, be16_to_cpu(dip->di_magic), dip);
3123 goto flush_out;
3124 }
3125 if (S_ISREG(VFS_I(ip)->i_mode)) {
3126 if (XFS_TEST_ERROR(
3127 ip->i_df.if_format != XFS_DINODE_FMT_EXTENTS &&
3128 ip->i_df.if_format != XFS_DINODE_FMT_BTREE,
3129 mp, XFS_ERRTAG_IFLUSH_3)) {
3130 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3131 "%s: Bad regular inode %llu, ptr "PTR_FMT,
3132 __func__, ip->i_ino, ip);
3133 goto flush_out;
3134 }
3135 } else if (S_ISDIR(VFS_I(ip)->i_mode)) {
3136 if (XFS_TEST_ERROR(
3137 ip->i_df.if_format != XFS_DINODE_FMT_EXTENTS &&
3138 ip->i_df.if_format != XFS_DINODE_FMT_BTREE &&
3139 ip->i_df.if_format != XFS_DINODE_FMT_LOCAL,
3140 mp, XFS_ERRTAG_IFLUSH_4)) {
3141 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3142 "%s: Bad directory inode %llu, ptr "PTR_FMT,
3143 __func__, ip->i_ino, ip);
3144 goto flush_out;
3145 }
3146 }
3147 if (XFS_TEST_ERROR(ip->i_df.if_nextents + xfs_ifork_nextents(&ip->i_af) >
3148 ip->i_nblocks, mp, XFS_ERRTAG_IFLUSH_5)) {
3149 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3150 "%s: detected corrupt incore inode %llu, "
3151 "total extents = %llu nblocks = %lld, ptr "PTR_FMT,
3152 __func__, ip->i_ino,
3153 ip->i_df.if_nextents + xfs_ifork_nextents(&ip->i_af),
3154 ip->i_nblocks, ip);
3155 goto flush_out;
3156 }
3157 if (XFS_TEST_ERROR(ip->i_forkoff > mp->m_sb.sb_inodesize,
3158 mp, XFS_ERRTAG_IFLUSH_6)) {
3159 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3160 "%s: bad inode %llu, forkoff 0x%x, ptr "PTR_FMT,
3161 __func__, ip->i_ino, ip->i_forkoff, ip);
3162 goto flush_out;
3163 }
3164
3165 /*
3166 * Inode item log recovery for v2 inodes are dependent on the flushiter
3167 * count for correct sequencing. We bump the flush iteration count so
3168 * we can detect flushes which postdate a log record during recovery.
3169 * This is redundant as we now log every change and hence this can't
3170 * happen but we need to still do it to ensure backwards compatibility
3171 * with old kernels that predate logging all inode changes.
3172 */
3173 if (!xfs_has_v3inodes(mp))
3174 ip->i_flushiter++;
3175
3176 /*
3177 * If there are inline format data / attr forks attached to this inode,
3178 * make sure they are not corrupt.
3179 */
3180 if (ip->i_df.if_format == XFS_DINODE_FMT_LOCAL &&
3181 xfs_ifork_verify_local_data(ip))
3182 goto flush_out;
3183 if (xfs_inode_has_attr_fork(ip) &&
3184 ip->i_af.if_format == XFS_DINODE_FMT_LOCAL &&
3185 xfs_ifork_verify_local_attr(ip))
3186 goto flush_out;
3187
3188 /*
3189 * Copy the dirty parts of the inode into the on-disk inode. We always
3190 * copy out the core of the inode, because if the inode is dirty at all
3191 * the core must be.
3192 */
3193 xfs_inode_to_disk(ip, dip, iip->ili_item.li_lsn);
3194
3195 /* Wrap, we never let the log put out DI_MAX_FLUSH */
3196 if (!xfs_has_v3inodes(mp)) {
3197 if (ip->i_flushiter == DI_MAX_FLUSH)
3198 ip->i_flushiter = 0;
3199 }
3200
3201 xfs_iflush_fork(ip, dip, iip, XFS_DATA_FORK);
3202 if (xfs_inode_has_attr_fork(ip))
3203 xfs_iflush_fork(ip, dip, iip, XFS_ATTR_FORK);
3204
3205 /*
3206 * We've recorded everything logged in the inode, so we'd like to clear
3207 * the ili_fields bits so we don't log and flush things unnecessarily.
3208 * However, we can't stop logging all this information until the data
3209 * we've copied into the disk buffer is written to disk. If we did we
3210 * might overwrite the copy of the inode in the log with all the data
3211 * after re-logging only part of it, and in the face of a crash we
3212 * wouldn't have all the data we need to recover.
3213 *
3214 * What we do is move the bits to the ili_last_fields field. When
3215 * logging the inode, these bits are moved back to the ili_fields field.
3216 * In the xfs_buf_inode_iodone() routine we clear ili_last_fields, since
3217 * we know that the information those bits represent is permanently on
3218 * disk. As long as the flush completes before the inode is logged
3219 * again, then both ili_fields and ili_last_fields will be cleared.
3220 */
3221 error = 0;
3222flush_out:
3223 spin_lock(&iip->ili_lock);
3224 iip->ili_last_fields = iip->ili_fields;
3225 iip->ili_fields = 0;
3226 iip->ili_fsync_fields = 0;
3227 spin_unlock(&iip->ili_lock);
3228
3229 /*
3230 * Store the current LSN of the inode so that we can tell whether the
3231 * item has moved in the AIL from xfs_buf_inode_iodone().
3232 */
3233 xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn,
3234 &iip->ili_item.li_lsn);
3235
3236 /* generate the checksum. */
3237 xfs_dinode_calc_crc(mp, dip);
3238 return error;
3239}
3240
3241/*
3242 * Non-blocking flush of dirty inode metadata into the backing buffer.
3243 *
3244 * The caller must have a reference to the inode and hold the cluster buffer
3245 * locked. The function will walk across all the inodes on the cluster buffer it
3246 * can find and lock without blocking, and flush them to the cluster buffer.
3247 *
3248 * On successful flushing of at least one inode, the caller must write out the
3249 * buffer and release it. If no inodes are flushed, -EAGAIN will be returned and
3250 * the caller needs to release the buffer. On failure, the filesystem will be
3251 * shut down, the buffer will have been unlocked and released, and EFSCORRUPTED
3252 * will be returned.
3253 */
3254int
3255xfs_iflush_cluster(
3256 struct xfs_buf *bp)
3257{
3258 struct xfs_mount *mp = bp->b_mount;
3259 struct xfs_log_item *lip, *n;
3260 struct xfs_inode *ip;
3261 struct xfs_inode_log_item *iip;
3262 int clcount = 0;
3263 int error = 0;
3264
3265 /*
3266 * We must use the safe variant here as on shutdown xfs_iflush_abort()
3267 * will remove itself from the list.
3268 */
3269 list_for_each_entry_safe(lip, n, &bp->b_li_list, li_bio_list) {
3270 iip = (struct xfs_inode_log_item *)lip;
3271 ip = iip->ili_inode;
3272
3273 /*
3274 * Quick and dirty check to avoid locks if possible.
3275 */
3276 if (__xfs_iflags_test(ip, XFS_IRECLAIM | XFS_IFLUSHING))
3277 continue;
3278 if (xfs_ipincount(ip))
3279 continue;
3280
3281 /*
3282 * The inode is still attached to the buffer, which means it is
3283 * dirty but reclaim might try to grab it. Check carefully for
3284 * that, and grab the ilock while still holding the i_flags_lock
3285 * to guarantee reclaim will not be able to reclaim this inode
3286 * once we drop the i_flags_lock.
3287 */
3288 spin_lock(&ip->i_flags_lock);
3289 ASSERT(!__xfs_iflags_test(ip, XFS_ISTALE));
3290 if (__xfs_iflags_test(ip, XFS_IRECLAIM | XFS_IFLUSHING)) {
3291 spin_unlock(&ip->i_flags_lock);
3292 continue;
3293 }
3294
3295 /*
3296 * ILOCK will pin the inode against reclaim and prevent
3297 * concurrent transactions modifying the inode while we are
3298 * flushing the inode. If we get the lock, set the flushing
3299 * state before we drop the i_flags_lock.
3300 */
3301 if (!xfs_ilock_nowait(ip, XFS_ILOCK_SHARED)) {
3302 spin_unlock(&ip->i_flags_lock);
3303 continue;
3304 }
3305 __xfs_iflags_set(ip, XFS_IFLUSHING);
3306 spin_unlock(&ip->i_flags_lock);
3307
3308 /*
3309 * Abort flushing this inode if we are shut down because the
3310 * inode may not currently be in the AIL. This can occur when
3311 * log I/O failure unpins the inode without inserting into the
3312 * AIL, leaving a dirty/unpinned inode attached to the buffer
3313 * that otherwise looks like it should be flushed.
3314 */
3315 if (xlog_is_shutdown(mp->m_log)) {
3316 xfs_iunpin_wait(ip);
3317 xfs_iflush_abort(ip);
3318 xfs_iunlock(ip, XFS_ILOCK_SHARED);
3319 error = -EIO;
3320 continue;
3321 }
3322
3323 /* don't block waiting on a log force to unpin dirty inodes */
3324 if (xfs_ipincount(ip)) {
3325 xfs_iflags_clear(ip, XFS_IFLUSHING);
3326 xfs_iunlock(ip, XFS_ILOCK_SHARED);
3327 continue;
3328 }
3329
3330 if (!xfs_inode_clean(ip))
3331 error = xfs_iflush(ip, bp);
3332 else
3333 xfs_iflags_clear(ip, XFS_IFLUSHING);
3334 xfs_iunlock(ip, XFS_ILOCK_SHARED);
3335 if (error)
3336 break;
3337 clcount++;
3338 }
3339
3340 if (error) {
3341 /*
3342 * Shutdown first so we kill the log before we release this
3343 * buffer. If it is an INODE_ALLOC buffer and pins the tail
3344 * of the log, failing it before the _log_ is shut down can
3345 * result in the log tail being moved forward in the journal
3346 * on disk because log writes can still be taking place. Hence
3347 * unpinning the tail will allow the ICREATE intent to be
3348 * removed from the log an recovery will fail with uninitialised
3349 * inode cluster buffers.
3350 */
3351 xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
3352 bp->b_flags |= XBF_ASYNC;
3353 xfs_buf_ioend_fail(bp);
3354 return error;
3355 }
3356
3357 if (!clcount)
3358 return -EAGAIN;
3359
3360 XFS_STATS_INC(mp, xs_icluster_flushcnt);
3361 XFS_STATS_ADD(mp, xs_icluster_flushinode, clcount);
3362 return 0;
3363
3364}
3365
3366/* Release an inode. */
3367void
3368xfs_irele(
3369 struct xfs_inode *ip)
3370{
3371 trace_xfs_irele(ip, _RET_IP_);
3372 iput(VFS_I(ip));
3373}
3374
3375/*
3376 * Ensure all commited transactions touching the inode are written to the log.
3377 */
3378int
3379xfs_log_force_inode(
3380 struct xfs_inode *ip)
3381{
3382 xfs_csn_t seq = 0;
3383
3384 xfs_ilock(ip, XFS_ILOCK_SHARED);
3385 if (xfs_ipincount(ip))
3386 seq = ip->i_itemp->ili_commit_seq;
3387 xfs_iunlock(ip, XFS_ILOCK_SHARED);
3388
3389 if (!seq)
3390 return 0;
3391 return xfs_log_force_seq(ip->i_mount, seq, XFS_LOG_SYNC, NULL);
3392}
3393
3394/*
3395 * Grab the exclusive iolock for a data copy from src to dest, making sure to
3396 * abide vfs locking order (lowest pointer value goes first) and breaking the
3397 * layout leases before proceeding. The loop is needed because we cannot call
3398 * the blocking break_layout() with the iolocks held, and therefore have to
3399 * back out both locks.
3400 */
3401static int
3402xfs_iolock_two_inodes_and_break_layout(
3403 struct inode *src,
3404 struct inode *dest)
3405{
3406 int error;
3407
3408 if (src > dest)
3409 swap(src, dest);
3410
3411retry:
3412 /* Wait to break both inodes' layouts before we start locking. */
3413 error = break_layout(src, true);
3414 if (error)
3415 return error;
3416 if (src != dest) {
3417 error = break_layout(dest, true);
3418 if (error)
3419 return error;
3420 }
3421
3422 /* Lock one inode and make sure nobody got in and leased it. */
3423 inode_lock(src);
3424 error = break_layout(src, false);
3425 if (error) {
3426 inode_unlock(src);
3427 if (error == -EWOULDBLOCK)
3428 goto retry;
3429 return error;
3430 }
3431
3432 if (src == dest)
3433 return 0;
3434
3435 /* Lock the other inode and make sure nobody got in and leased it. */
3436 inode_lock_nested(dest, I_MUTEX_NONDIR2);
3437 error = break_layout(dest, false);
3438 if (error) {
3439 inode_unlock(src);
3440 inode_unlock(dest);
3441 if (error == -EWOULDBLOCK)
3442 goto retry;
3443 return error;
3444 }
3445
3446 return 0;
3447}
3448
3449static int
3450xfs_mmaplock_two_inodes_and_break_dax_layout(
3451 struct xfs_inode *ip1,
3452 struct xfs_inode *ip2)
3453{
3454 int error;
3455 bool retry;
3456 struct page *page;
3457
3458 if (ip1->i_ino > ip2->i_ino)
3459 swap(ip1, ip2);
3460
3461again:
3462 retry = false;
3463 /* Lock the first inode */
3464 xfs_ilock(ip1, XFS_MMAPLOCK_EXCL);
3465 error = xfs_break_dax_layouts(VFS_I(ip1), &retry);
3466 if (error || retry) {
3467 xfs_iunlock(ip1, XFS_MMAPLOCK_EXCL);
3468 if (error == 0 && retry)
3469 goto again;
3470 return error;
3471 }
3472
3473 if (ip1 == ip2)
3474 return 0;
3475
3476 /* Nested lock the second inode */
3477 xfs_ilock(ip2, xfs_lock_inumorder(XFS_MMAPLOCK_EXCL, 1));
3478 /*
3479 * We cannot use xfs_break_dax_layouts() directly here because it may
3480 * need to unlock & lock the XFS_MMAPLOCK_EXCL which is not suitable
3481 * for this nested lock case.
3482 */
3483 page = dax_layout_busy_page(VFS_I(ip2)->i_mapping);
3484 if (page && page_ref_count(page) != 1) {
3485 xfs_iunlock(ip2, XFS_MMAPLOCK_EXCL);
3486 xfs_iunlock(ip1, XFS_MMAPLOCK_EXCL);
3487 goto again;
3488 }
3489
3490 return 0;
3491}
3492
3493/*
3494 * Lock two inodes so that userspace cannot initiate I/O via file syscalls or
3495 * mmap activity.
3496 */
3497int
3498xfs_ilock2_io_mmap(
3499 struct xfs_inode *ip1,
3500 struct xfs_inode *ip2)
3501{
3502 int ret;
3503
3504 ret = xfs_iolock_two_inodes_and_break_layout(VFS_I(ip1), VFS_I(ip2));
3505 if (ret)
3506 return ret;
3507
3508 if (IS_DAX(VFS_I(ip1)) && IS_DAX(VFS_I(ip2))) {
3509 ret = xfs_mmaplock_two_inodes_and_break_dax_layout(ip1, ip2);
3510 if (ret) {
3511 inode_unlock(VFS_I(ip2));
3512 if (ip1 != ip2)
3513 inode_unlock(VFS_I(ip1));
3514 return ret;
3515 }
3516 } else
3517 filemap_invalidate_lock_two(VFS_I(ip1)->i_mapping,
3518 VFS_I(ip2)->i_mapping);
3519
3520 return 0;
3521}
3522
3523/* Unlock both inodes to allow IO and mmap activity. */
3524void
3525xfs_iunlock2_io_mmap(
3526 struct xfs_inode *ip1,
3527 struct xfs_inode *ip2)
3528{
3529 if (IS_DAX(VFS_I(ip1)) && IS_DAX(VFS_I(ip2))) {
3530 xfs_iunlock(ip2, XFS_MMAPLOCK_EXCL);
3531 if (ip1 != ip2)
3532 xfs_iunlock(ip1, XFS_MMAPLOCK_EXCL);
3533 } else
3534 filemap_invalidate_unlock_two(VFS_I(ip1)->i_mapping,
3535 VFS_I(ip2)->i_mapping);
3536
3537 inode_unlock(VFS_I(ip2));
3538 if (ip1 != ip2)
3539 inode_unlock(VFS_I(ip1));
3540}
1/*
2 * Copyright (c) 2000-2006 Silicon Graphics, Inc.
3 * All Rights Reserved.
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it would be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
17 */
18#include <linux/log2.h>
19#include <linux/iversion.h>
20
21#include "xfs.h"
22#include "xfs_fs.h"
23#include "xfs_shared.h"
24#include "xfs_format.h"
25#include "xfs_log_format.h"
26#include "xfs_trans_resv.h"
27#include "xfs_sb.h"
28#include "xfs_mount.h"
29#include "xfs_defer.h"
30#include "xfs_inode.h"
31#include "xfs_da_format.h"
32#include "xfs_da_btree.h"
33#include "xfs_dir2.h"
34#include "xfs_attr_sf.h"
35#include "xfs_attr.h"
36#include "xfs_trans_space.h"
37#include "xfs_trans.h"
38#include "xfs_buf_item.h"
39#include "xfs_inode_item.h"
40#include "xfs_ialloc.h"
41#include "xfs_bmap.h"
42#include "xfs_bmap_util.h"
43#include "xfs_errortag.h"
44#include "xfs_error.h"
45#include "xfs_quota.h"
46#include "xfs_filestream.h"
47#include "xfs_cksum.h"
48#include "xfs_trace.h"
49#include "xfs_icache.h"
50#include "xfs_symlink.h"
51#include "xfs_trans_priv.h"
52#include "xfs_log.h"
53#include "xfs_bmap_btree.h"
54#include "xfs_reflink.h"
55#include "xfs_dir2_priv.h"
56
57kmem_zone_t *xfs_inode_zone;
58
59/*
60 * Used in xfs_itruncate_extents(). This is the maximum number of extents
61 * freed from a file in a single transaction.
62 */
63#define XFS_ITRUNC_MAX_EXTENTS 2
64
65STATIC int xfs_iflush_int(struct xfs_inode *, struct xfs_buf *);
66STATIC int xfs_iunlink(struct xfs_trans *, struct xfs_inode *);
67STATIC int xfs_iunlink_remove(struct xfs_trans *, struct xfs_inode *);
68
69/*
70 * helper function to extract extent size hint from inode
71 */
72xfs_extlen_t
73xfs_get_extsz_hint(
74 struct xfs_inode *ip)
75{
76 if ((ip->i_d.di_flags & XFS_DIFLAG_EXTSIZE) && ip->i_d.di_extsize)
77 return ip->i_d.di_extsize;
78 if (XFS_IS_REALTIME_INODE(ip))
79 return ip->i_mount->m_sb.sb_rextsize;
80 return 0;
81}
82
83/*
84 * Helper function to extract CoW extent size hint from inode.
85 * Between the extent size hint and the CoW extent size hint, we
86 * return the greater of the two. If the value is zero (automatic),
87 * use the default size.
88 */
89xfs_extlen_t
90xfs_get_cowextsz_hint(
91 struct xfs_inode *ip)
92{
93 xfs_extlen_t a, b;
94
95 a = 0;
96 if (ip->i_d.di_flags2 & XFS_DIFLAG2_COWEXTSIZE)
97 a = ip->i_d.di_cowextsize;
98 b = xfs_get_extsz_hint(ip);
99
100 a = max(a, b);
101 if (a == 0)
102 return XFS_DEFAULT_COWEXTSZ_HINT;
103 return a;
104}
105
106/*
107 * These two are wrapper routines around the xfs_ilock() routine used to
108 * centralize some grungy code. They are used in places that wish to lock the
109 * inode solely for reading the extents. The reason these places can't just
110 * call xfs_ilock(ip, XFS_ILOCK_SHARED) is that the inode lock also guards to
111 * bringing in of the extents from disk for a file in b-tree format. If the
112 * inode is in b-tree format, then we need to lock the inode exclusively until
113 * the extents are read in. Locking it exclusively all the time would limit
114 * our parallelism unnecessarily, though. What we do instead is check to see
115 * if the extents have been read in yet, and only lock the inode exclusively
116 * if they have not.
117 *
118 * The functions return a value which should be given to the corresponding
119 * xfs_iunlock() call.
120 */
121uint
122xfs_ilock_data_map_shared(
123 struct xfs_inode *ip)
124{
125 uint lock_mode = XFS_ILOCK_SHARED;
126
127 if (ip->i_d.di_format == XFS_DINODE_FMT_BTREE &&
128 (ip->i_df.if_flags & XFS_IFEXTENTS) == 0)
129 lock_mode = XFS_ILOCK_EXCL;
130 xfs_ilock(ip, lock_mode);
131 return lock_mode;
132}
133
134uint
135xfs_ilock_attr_map_shared(
136 struct xfs_inode *ip)
137{
138 uint lock_mode = XFS_ILOCK_SHARED;
139
140 if (ip->i_d.di_aformat == XFS_DINODE_FMT_BTREE &&
141 (ip->i_afp->if_flags & XFS_IFEXTENTS) == 0)
142 lock_mode = XFS_ILOCK_EXCL;
143 xfs_ilock(ip, lock_mode);
144 return lock_mode;
145}
146
147/*
148 * In addition to i_rwsem in the VFS inode, the xfs inode contains 2
149 * multi-reader locks: i_mmap_lock and the i_lock. This routine allows
150 * various combinations of the locks to be obtained.
151 *
152 * The 3 locks should always be ordered so that the IO lock is obtained first,
153 * the mmap lock second and the ilock last in order to prevent deadlock.
154 *
155 * Basic locking order:
156 *
157 * i_rwsem -> i_mmap_lock -> page_lock -> i_ilock
158 *
159 * mmap_sem locking order:
160 *
161 * i_rwsem -> page lock -> mmap_sem
162 * mmap_sem -> i_mmap_lock -> page_lock
163 *
164 * The difference in mmap_sem locking order mean that we cannot hold the
165 * i_mmap_lock over syscall based read(2)/write(2) based IO. These IO paths can
166 * fault in pages during copy in/out (for buffered IO) or require the mmap_sem
167 * in get_user_pages() to map the user pages into the kernel address space for
168 * direct IO. Similarly the i_rwsem cannot be taken inside a page fault because
169 * page faults already hold the mmap_sem.
170 *
171 * Hence to serialise fully against both syscall and mmap based IO, we need to
172 * take both the i_rwsem and the i_mmap_lock. These locks should *only* be both
173 * taken in places where we need to invalidate the page cache in a race
174 * free manner (e.g. truncate, hole punch and other extent manipulation
175 * functions).
176 */
177void
178xfs_ilock(
179 xfs_inode_t *ip,
180 uint lock_flags)
181{
182 trace_xfs_ilock(ip, lock_flags, _RET_IP_);
183
184 /*
185 * You can't set both SHARED and EXCL for the same lock,
186 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
187 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
188 */
189 ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
190 (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
191 ASSERT((lock_flags & (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)) !=
192 (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL));
193 ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
194 (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
195 ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0);
196
197 if (lock_flags & XFS_IOLOCK_EXCL) {
198 down_write_nested(&VFS_I(ip)->i_rwsem,
199 XFS_IOLOCK_DEP(lock_flags));
200 } else if (lock_flags & XFS_IOLOCK_SHARED) {
201 down_read_nested(&VFS_I(ip)->i_rwsem,
202 XFS_IOLOCK_DEP(lock_flags));
203 }
204
205 if (lock_flags & XFS_MMAPLOCK_EXCL)
206 mrupdate_nested(&ip->i_mmaplock, XFS_MMAPLOCK_DEP(lock_flags));
207 else if (lock_flags & XFS_MMAPLOCK_SHARED)
208 mraccess_nested(&ip->i_mmaplock, XFS_MMAPLOCK_DEP(lock_flags));
209
210 if (lock_flags & XFS_ILOCK_EXCL)
211 mrupdate_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
212 else if (lock_flags & XFS_ILOCK_SHARED)
213 mraccess_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
214}
215
216/*
217 * This is just like xfs_ilock(), except that the caller
218 * is guaranteed not to sleep. It returns 1 if it gets
219 * the requested locks and 0 otherwise. If the IO lock is
220 * obtained but the inode lock cannot be, then the IO lock
221 * is dropped before returning.
222 *
223 * ip -- the inode being locked
224 * lock_flags -- this parameter indicates the inode's locks to be
225 * to be locked. See the comment for xfs_ilock() for a list
226 * of valid values.
227 */
228int
229xfs_ilock_nowait(
230 xfs_inode_t *ip,
231 uint lock_flags)
232{
233 trace_xfs_ilock_nowait(ip, lock_flags, _RET_IP_);
234
235 /*
236 * You can't set both SHARED and EXCL for the same lock,
237 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
238 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
239 */
240 ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
241 (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
242 ASSERT((lock_flags & (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)) !=
243 (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL));
244 ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
245 (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
246 ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0);
247
248 if (lock_flags & XFS_IOLOCK_EXCL) {
249 if (!down_write_trylock(&VFS_I(ip)->i_rwsem))
250 goto out;
251 } else if (lock_flags & XFS_IOLOCK_SHARED) {
252 if (!down_read_trylock(&VFS_I(ip)->i_rwsem))
253 goto out;
254 }
255
256 if (lock_flags & XFS_MMAPLOCK_EXCL) {
257 if (!mrtryupdate(&ip->i_mmaplock))
258 goto out_undo_iolock;
259 } else if (lock_flags & XFS_MMAPLOCK_SHARED) {
260 if (!mrtryaccess(&ip->i_mmaplock))
261 goto out_undo_iolock;
262 }
263
264 if (lock_flags & XFS_ILOCK_EXCL) {
265 if (!mrtryupdate(&ip->i_lock))
266 goto out_undo_mmaplock;
267 } else if (lock_flags & XFS_ILOCK_SHARED) {
268 if (!mrtryaccess(&ip->i_lock))
269 goto out_undo_mmaplock;
270 }
271 return 1;
272
273out_undo_mmaplock:
274 if (lock_flags & XFS_MMAPLOCK_EXCL)
275 mrunlock_excl(&ip->i_mmaplock);
276 else if (lock_flags & XFS_MMAPLOCK_SHARED)
277 mrunlock_shared(&ip->i_mmaplock);
278out_undo_iolock:
279 if (lock_flags & XFS_IOLOCK_EXCL)
280 up_write(&VFS_I(ip)->i_rwsem);
281 else if (lock_flags & XFS_IOLOCK_SHARED)
282 up_read(&VFS_I(ip)->i_rwsem);
283out:
284 return 0;
285}
286
287/*
288 * xfs_iunlock() is used to drop the inode locks acquired with
289 * xfs_ilock() and xfs_ilock_nowait(). The caller must pass
290 * in the flags given to xfs_ilock() or xfs_ilock_nowait() so
291 * that we know which locks to drop.
292 *
293 * ip -- the inode being unlocked
294 * lock_flags -- this parameter indicates the inode's locks to be
295 * to be unlocked. See the comment for xfs_ilock() for a list
296 * of valid values for this parameter.
297 *
298 */
299void
300xfs_iunlock(
301 xfs_inode_t *ip,
302 uint lock_flags)
303{
304 /*
305 * You can't set both SHARED and EXCL for the same lock,
306 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
307 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
308 */
309 ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
310 (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
311 ASSERT((lock_flags & (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)) !=
312 (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL));
313 ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
314 (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
315 ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0);
316 ASSERT(lock_flags != 0);
317
318 if (lock_flags & XFS_IOLOCK_EXCL)
319 up_write(&VFS_I(ip)->i_rwsem);
320 else if (lock_flags & XFS_IOLOCK_SHARED)
321 up_read(&VFS_I(ip)->i_rwsem);
322
323 if (lock_flags & XFS_MMAPLOCK_EXCL)
324 mrunlock_excl(&ip->i_mmaplock);
325 else if (lock_flags & XFS_MMAPLOCK_SHARED)
326 mrunlock_shared(&ip->i_mmaplock);
327
328 if (lock_flags & XFS_ILOCK_EXCL)
329 mrunlock_excl(&ip->i_lock);
330 else if (lock_flags & XFS_ILOCK_SHARED)
331 mrunlock_shared(&ip->i_lock);
332
333 trace_xfs_iunlock(ip, lock_flags, _RET_IP_);
334}
335
336/*
337 * give up write locks. the i/o lock cannot be held nested
338 * if it is being demoted.
339 */
340void
341xfs_ilock_demote(
342 xfs_inode_t *ip,
343 uint lock_flags)
344{
345 ASSERT(lock_flags & (XFS_IOLOCK_EXCL|XFS_MMAPLOCK_EXCL|XFS_ILOCK_EXCL));
346 ASSERT((lock_flags &
347 ~(XFS_IOLOCK_EXCL|XFS_MMAPLOCK_EXCL|XFS_ILOCK_EXCL)) == 0);
348
349 if (lock_flags & XFS_ILOCK_EXCL)
350 mrdemote(&ip->i_lock);
351 if (lock_flags & XFS_MMAPLOCK_EXCL)
352 mrdemote(&ip->i_mmaplock);
353 if (lock_flags & XFS_IOLOCK_EXCL)
354 downgrade_write(&VFS_I(ip)->i_rwsem);
355
356 trace_xfs_ilock_demote(ip, lock_flags, _RET_IP_);
357}
358
359#if defined(DEBUG) || defined(XFS_WARN)
360int
361xfs_isilocked(
362 xfs_inode_t *ip,
363 uint lock_flags)
364{
365 if (lock_flags & (XFS_ILOCK_EXCL|XFS_ILOCK_SHARED)) {
366 if (!(lock_flags & XFS_ILOCK_SHARED))
367 return !!ip->i_lock.mr_writer;
368 return rwsem_is_locked(&ip->i_lock.mr_lock);
369 }
370
371 if (lock_flags & (XFS_MMAPLOCK_EXCL|XFS_MMAPLOCK_SHARED)) {
372 if (!(lock_flags & XFS_MMAPLOCK_SHARED))
373 return !!ip->i_mmaplock.mr_writer;
374 return rwsem_is_locked(&ip->i_mmaplock.mr_lock);
375 }
376
377 if (lock_flags & (XFS_IOLOCK_EXCL|XFS_IOLOCK_SHARED)) {
378 if (!(lock_flags & XFS_IOLOCK_SHARED))
379 return !debug_locks ||
380 lockdep_is_held_type(&VFS_I(ip)->i_rwsem, 0);
381 return rwsem_is_locked(&VFS_I(ip)->i_rwsem);
382 }
383
384 ASSERT(0);
385 return 0;
386}
387#endif
388
389/*
390 * xfs_lockdep_subclass_ok() is only used in an ASSERT, so is only called when
391 * DEBUG or XFS_WARN is set. And MAX_LOCKDEP_SUBCLASSES is then only defined
392 * when CONFIG_LOCKDEP is set. Hence the complex define below to avoid build
393 * errors and warnings.
394 */
395#if (defined(DEBUG) || defined(XFS_WARN)) && defined(CONFIG_LOCKDEP)
396static bool
397xfs_lockdep_subclass_ok(
398 int subclass)
399{
400 return subclass < MAX_LOCKDEP_SUBCLASSES;
401}
402#else
403#define xfs_lockdep_subclass_ok(subclass) (true)
404#endif
405
406/*
407 * Bump the subclass so xfs_lock_inodes() acquires each lock with a different
408 * value. This can be called for any type of inode lock combination, including
409 * parent locking. Care must be taken to ensure we don't overrun the subclass
410 * storage fields in the class mask we build.
411 */
412static inline int
413xfs_lock_inumorder(int lock_mode, int subclass)
414{
415 int class = 0;
416
417 ASSERT(!(lock_mode & (XFS_ILOCK_PARENT | XFS_ILOCK_RTBITMAP |
418 XFS_ILOCK_RTSUM)));
419 ASSERT(xfs_lockdep_subclass_ok(subclass));
420
421 if (lock_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)) {
422 ASSERT(subclass <= XFS_IOLOCK_MAX_SUBCLASS);
423 class += subclass << XFS_IOLOCK_SHIFT;
424 }
425
426 if (lock_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) {
427 ASSERT(subclass <= XFS_MMAPLOCK_MAX_SUBCLASS);
428 class += subclass << XFS_MMAPLOCK_SHIFT;
429 }
430
431 if (lock_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)) {
432 ASSERT(subclass <= XFS_ILOCK_MAX_SUBCLASS);
433 class += subclass << XFS_ILOCK_SHIFT;
434 }
435
436 return (lock_mode & ~XFS_LOCK_SUBCLASS_MASK) | class;
437}
438
439/*
440 * The following routine will lock n inodes in exclusive mode. We assume the
441 * caller calls us with the inodes in i_ino order.
442 *
443 * We need to detect deadlock where an inode that we lock is in the AIL and we
444 * start waiting for another inode that is locked by a thread in a long running
445 * transaction (such as truncate). This can result in deadlock since the long
446 * running trans might need to wait for the inode we just locked in order to
447 * push the tail and free space in the log.
448 *
449 * xfs_lock_inodes() can only be used to lock one type of lock at a time -
450 * the iolock, the mmaplock or the ilock, but not more than one at a time. If we
451 * lock more than one at a time, lockdep will report false positives saying we
452 * have violated locking orders.
453 */
454static void
455xfs_lock_inodes(
456 xfs_inode_t **ips,
457 int inodes,
458 uint lock_mode)
459{
460 int attempts = 0, i, j, try_lock;
461 xfs_log_item_t *lp;
462
463 /*
464 * Currently supports between 2 and 5 inodes with exclusive locking. We
465 * support an arbitrary depth of locking here, but absolute limits on
466 * inodes depend on the the type of locking and the limits placed by
467 * lockdep annotations in xfs_lock_inumorder. These are all checked by
468 * the asserts.
469 */
470 ASSERT(ips && inodes >= 2 && inodes <= 5);
471 ASSERT(lock_mode & (XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL |
472 XFS_ILOCK_EXCL));
473 ASSERT(!(lock_mode & (XFS_IOLOCK_SHARED | XFS_MMAPLOCK_SHARED |
474 XFS_ILOCK_SHARED)));
475 ASSERT(!(lock_mode & XFS_MMAPLOCK_EXCL) ||
476 inodes <= XFS_MMAPLOCK_MAX_SUBCLASS + 1);
477 ASSERT(!(lock_mode & XFS_ILOCK_EXCL) ||
478 inodes <= XFS_ILOCK_MAX_SUBCLASS + 1);
479
480 if (lock_mode & XFS_IOLOCK_EXCL) {
481 ASSERT(!(lock_mode & (XFS_MMAPLOCK_EXCL | XFS_ILOCK_EXCL)));
482 } else if (lock_mode & XFS_MMAPLOCK_EXCL)
483 ASSERT(!(lock_mode & XFS_ILOCK_EXCL));
484
485 try_lock = 0;
486 i = 0;
487again:
488 for (; i < inodes; i++) {
489 ASSERT(ips[i]);
490
491 if (i && (ips[i] == ips[i - 1])) /* Already locked */
492 continue;
493
494 /*
495 * If try_lock is not set yet, make sure all locked inodes are
496 * not in the AIL. If any are, set try_lock to be used later.
497 */
498 if (!try_lock) {
499 for (j = (i - 1); j >= 0 && !try_lock; j--) {
500 lp = (xfs_log_item_t *)ips[j]->i_itemp;
501 if (lp && (lp->li_flags & XFS_LI_IN_AIL))
502 try_lock++;
503 }
504 }
505
506 /*
507 * If any of the previous locks we have locked is in the AIL,
508 * we must TRY to get the second and subsequent locks. If
509 * we can't get any, we must release all we have
510 * and try again.
511 */
512 if (!try_lock) {
513 xfs_ilock(ips[i], xfs_lock_inumorder(lock_mode, i));
514 continue;
515 }
516
517 /* try_lock means we have an inode locked that is in the AIL. */
518 ASSERT(i != 0);
519 if (xfs_ilock_nowait(ips[i], xfs_lock_inumorder(lock_mode, i)))
520 continue;
521
522 /*
523 * Unlock all previous guys and try again. xfs_iunlock will try
524 * to push the tail if the inode is in the AIL.
525 */
526 attempts++;
527 for (j = i - 1; j >= 0; j--) {
528 /*
529 * Check to see if we've already unlocked this one. Not
530 * the first one going back, and the inode ptr is the
531 * same.
532 */
533 if (j != (i - 1) && ips[j] == ips[j + 1])
534 continue;
535
536 xfs_iunlock(ips[j], lock_mode);
537 }
538
539 if ((attempts % 5) == 0) {
540 delay(1); /* Don't just spin the CPU */
541 }
542 i = 0;
543 try_lock = 0;
544 goto again;
545 }
546}
547
548/*
549 * xfs_lock_two_inodes() can only be used to lock one type of lock at a time -
550 * the mmaplock or the ilock, but not more than one type at a time. If we lock
551 * more than one at a time, lockdep will report false positives saying we have
552 * violated locking orders. The iolock must be double-locked separately since
553 * we use i_rwsem for that. We now support taking one lock EXCL and the other
554 * SHARED.
555 */
556void
557xfs_lock_two_inodes(
558 struct xfs_inode *ip0,
559 uint ip0_mode,
560 struct xfs_inode *ip1,
561 uint ip1_mode)
562{
563 struct xfs_inode *temp;
564 uint mode_temp;
565 int attempts = 0;
566 xfs_log_item_t *lp;
567
568 ASSERT(hweight32(ip0_mode) == 1);
569 ASSERT(hweight32(ip1_mode) == 1);
570 ASSERT(!(ip0_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)));
571 ASSERT(!(ip1_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)));
572 ASSERT(!(ip0_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) ||
573 !(ip0_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)));
574 ASSERT(!(ip1_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) ||
575 !(ip1_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)));
576 ASSERT(!(ip1_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) ||
577 !(ip0_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)));
578 ASSERT(!(ip0_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) ||
579 !(ip1_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)));
580
581 ASSERT(ip0->i_ino != ip1->i_ino);
582
583 if (ip0->i_ino > ip1->i_ino) {
584 temp = ip0;
585 ip0 = ip1;
586 ip1 = temp;
587 mode_temp = ip0_mode;
588 ip0_mode = ip1_mode;
589 ip1_mode = mode_temp;
590 }
591
592 again:
593 xfs_ilock(ip0, xfs_lock_inumorder(ip0_mode, 0));
594
595 /*
596 * If the first lock we have locked is in the AIL, we must TRY to get
597 * the second lock. If we can't get it, we must release the first one
598 * and try again.
599 */
600 lp = (xfs_log_item_t *)ip0->i_itemp;
601 if (lp && (lp->li_flags & XFS_LI_IN_AIL)) {
602 if (!xfs_ilock_nowait(ip1, xfs_lock_inumorder(ip1_mode, 1))) {
603 xfs_iunlock(ip0, ip0_mode);
604 if ((++attempts % 5) == 0)
605 delay(1); /* Don't just spin the CPU */
606 goto again;
607 }
608 } else {
609 xfs_ilock(ip1, xfs_lock_inumorder(ip1_mode, 1));
610 }
611}
612
613void
614__xfs_iflock(
615 struct xfs_inode *ip)
616{
617 wait_queue_head_t *wq = bit_waitqueue(&ip->i_flags, __XFS_IFLOCK_BIT);
618 DEFINE_WAIT_BIT(wait, &ip->i_flags, __XFS_IFLOCK_BIT);
619
620 do {
621 prepare_to_wait_exclusive(wq, &wait.wq_entry, TASK_UNINTERRUPTIBLE);
622 if (xfs_isiflocked(ip))
623 io_schedule();
624 } while (!xfs_iflock_nowait(ip));
625
626 finish_wait(wq, &wait.wq_entry);
627}
628
629STATIC uint
630_xfs_dic2xflags(
631 uint16_t di_flags,
632 uint64_t di_flags2,
633 bool has_attr)
634{
635 uint flags = 0;
636
637 if (di_flags & XFS_DIFLAG_ANY) {
638 if (di_flags & XFS_DIFLAG_REALTIME)
639 flags |= FS_XFLAG_REALTIME;
640 if (di_flags & XFS_DIFLAG_PREALLOC)
641 flags |= FS_XFLAG_PREALLOC;
642 if (di_flags & XFS_DIFLAG_IMMUTABLE)
643 flags |= FS_XFLAG_IMMUTABLE;
644 if (di_flags & XFS_DIFLAG_APPEND)
645 flags |= FS_XFLAG_APPEND;
646 if (di_flags & XFS_DIFLAG_SYNC)
647 flags |= FS_XFLAG_SYNC;
648 if (di_flags & XFS_DIFLAG_NOATIME)
649 flags |= FS_XFLAG_NOATIME;
650 if (di_flags & XFS_DIFLAG_NODUMP)
651 flags |= FS_XFLAG_NODUMP;
652 if (di_flags & XFS_DIFLAG_RTINHERIT)
653 flags |= FS_XFLAG_RTINHERIT;
654 if (di_flags & XFS_DIFLAG_PROJINHERIT)
655 flags |= FS_XFLAG_PROJINHERIT;
656 if (di_flags & XFS_DIFLAG_NOSYMLINKS)
657 flags |= FS_XFLAG_NOSYMLINKS;
658 if (di_flags & XFS_DIFLAG_EXTSIZE)
659 flags |= FS_XFLAG_EXTSIZE;
660 if (di_flags & XFS_DIFLAG_EXTSZINHERIT)
661 flags |= FS_XFLAG_EXTSZINHERIT;
662 if (di_flags & XFS_DIFLAG_NODEFRAG)
663 flags |= FS_XFLAG_NODEFRAG;
664 if (di_flags & XFS_DIFLAG_FILESTREAM)
665 flags |= FS_XFLAG_FILESTREAM;
666 }
667
668 if (di_flags2 & XFS_DIFLAG2_ANY) {
669 if (di_flags2 & XFS_DIFLAG2_DAX)
670 flags |= FS_XFLAG_DAX;
671 if (di_flags2 & XFS_DIFLAG2_COWEXTSIZE)
672 flags |= FS_XFLAG_COWEXTSIZE;
673 }
674
675 if (has_attr)
676 flags |= FS_XFLAG_HASATTR;
677
678 return flags;
679}
680
681uint
682xfs_ip2xflags(
683 struct xfs_inode *ip)
684{
685 struct xfs_icdinode *dic = &ip->i_d;
686
687 return _xfs_dic2xflags(dic->di_flags, dic->di_flags2, XFS_IFORK_Q(ip));
688}
689
690/*
691 * Lookups up an inode from "name". If ci_name is not NULL, then a CI match
692 * is allowed, otherwise it has to be an exact match. If a CI match is found,
693 * ci_name->name will point to a the actual name (caller must free) or
694 * will be set to NULL if an exact match is found.
695 */
696int
697xfs_lookup(
698 xfs_inode_t *dp,
699 struct xfs_name *name,
700 xfs_inode_t **ipp,
701 struct xfs_name *ci_name)
702{
703 xfs_ino_t inum;
704 int error;
705
706 trace_xfs_lookup(dp, name);
707
708 if (XFS_FORCED_SHUTDOWN(dp->i_mount))
709 return -EIO;
710
711 error = xfs_dir_lookup(NULL, dp, name, &inum, ci_name);
712 if (error)
713 goto out_unlock;
714
715 error = xfs_iget(dp->i_mount, NULL, inum, 0, 0, ipp);
716 if (error)
717 goto out_free_name;
718
719 return 0;
720
721out_free_name:
722 if (ci_name)
723 kmem_free(ci_name->name);
724out_unlock:
725 *ipp = NULL;
726 return error;
727}
728
729/*
730 * Allocate an inode on disk and return a copy of its in-core version.
731 * The in-core inode is locked exclusively. Set mode, nlink, and rdev
732 * appropriately within the inode. The uid and gid for the inode are
733 * set according to the contents of the given cred structure.
734 *
735 * Use xfs_dialloc() to allocate the on-disk inode. If xfs_dialloc()
736 * has a free inode available, call xfs_iget() to obtain the in-core
737 * version of the allocated inode. Finally, fill in the inode and
738 * log its initial contents. In this case, ialloc_context would be
739 * set to NULL.
740 *
741 * If xfs_dialloc() does not have an available inode, it will replenish
742 * its supply by doing an allocation. Since we can only do one
743 * allocation within a transaction without deadlocks, we must commit
744 * the current transaction before returning the inode itself.
745 * In this case, therefore, we will set ialloc_context and return.
746 * The caller should then commit the current transaction, start a new
747 * transaction, and call xfs_ialloc() again to actually get the inode.
748 *
749 * To ensure that some other process does not grab the inode that
750 * was allocated during the first call to xfs_ialloc(), this routine
751 * also returns the [locked] bp pointing to the head of the freelist
752 * as ialloc_context. The caller should hold this buffer across
753 * the commit and pass it back into this routine on the second call.
754 *
755 * If we are allocating quota inodes, we do not have a parent inode
756 * to attach to or associate with (i.e. pip == NULL) because they
757 * are not linked into the directory structure - they are attached
758 * directly to the superblock - and so have no parent.
759 */
760static int
761xfs_ialloc(
762 xfs_trans_t *tp,
763 xfs_inode_t *pip,
764 umode_t mode,
765 xfs_nlink_t nlink,
766 dev_t rdev,
767 prid_t prid,
768 xfs_buf_t **ialloc_context,
769 xfs_inode_t **ipp)
770{
771 struct xfs_mount *mp = tp->t_mountp;
772 xfs_ino_t ino;
773 xfs_inode_t *ip;
774 uint flags;
775 int error;
776 struct timespec tv;
777 struct inode *inode;
778
779 /*
780 * Call the space management code to pick
781 * the on-disk inode to be allocated.
782 */
783 error = xfs_dialloc(tp, pip ? pip->i_ino : 0, mode,
784 ialloc_context, &ino);
785 if (error)
786 return error;
787 if (*ialloc_context || ino == NULLFSINO) {
788 *ipp = NULL;
789 return 0;
790 }
791 ASSERT(*ialloc_context == NULL);
792
793 /*
794 * Get the in-core inode with the lock held exclusively.
795 * This is because we're setting fields here we need
796 * to prevent others from looking at until we're done.
797 */
798 error = xfs_iget(mp, tp, ino, XFS_IGET_CREATE,
799 XFS_ILOCK_EXCL, &ip);
800 if (error)
801 return error;
802 ASSERT(ip != NULL);
803 inode = VFS_I(ip);
804
805 /*
806 * We always convert v1 inodes to v2 now - we only support filesystems
807 * with >= v2 inode capability, so there is no reason for ever leaving
808 * an inode in v1 format.
809 */
810 if (ip->i_d.di_version == 1)
811 ip->i_d.di_version = 2;
812
813 inode->i_mode = mode;
814 set_nlink(inode, nlink);
815 ip->i_d.di_uid = xfs_kuid_to_uid(current_fsuid());
816 ip->i_d.di_gid = xfs_kgid_to_gid(current_fsgid());
817 inode->i_rdev = rdev;
818 xfs_set_projid(ip, prid);
819
820 if (pip && XFS_INHERIT_GID(pip)) {
821 ip->i_d.di_gid = pip->i_d.di_gid;
822 if ((VFS_I(pip)->i_mode & S_ISGID) && S_ISDIR(mode))
823 inode->i_mode |= S_ISGID;
824 }
825
826 /*
827 * If the group ID of the new file does not match the effective group
828 * ID or one of the supplementary group IDs, the S_ISGID bit is cleared
829 * (and only if the irix_sgid_inherit compatibility variable is set).
830 */
831 if ((irix_sgid_inherit) &&
832 (inode->i_mode & S_ISGID) &&
833 (!in_group_p(xfs_gid_to_kgid(ip->i_d.di_gid))))
834 inode->i_mode &= ~S_ISGID;
835
836 ip->i_d.di_size = 0;
837 ip->i_d.di_nextents = 0;
838 ASSERT(ip->i_d.di_nblocks == 0);
839
840 tv = current_time(inode);
841 inode->i_mtime = tv;
842 inode->i_atime = tv;
843 inode->i_ctime = tv;
844
845 ip->i_d.di_extsize = 0;
846 ip->i_d.di_dmevmask = 0;
847 ip->i_d.di_dmstate = 0;
848 ip->i_d.di_flags = 0;
849
850 if (ip->i_d.di_version == 3) {
851 inode_set_iversion(inode, 1);
852 ip->i_d.di_flags2 = 0;
853 ip->i_d.di_cowextsize = 0;
854 ip->i_d.di_crtime.t_sec = (int32_t)tv.tv_sec;
855 ip->i_d.di_crtime.t_nsec = (int32_t)tv.tv_nsec;
856 }
857
858
859 flags = XFS_ILOG_CORE;
860 switch (mode & S_IFMT) {
861 case S_IFIFO:
862 case S_IFCHR:
863 case S_IFBLK:
864 case S_IFSOCK:
865 ip->i_d.di_format = XFS_DINODE_FMT_DEV;
866 ip->i_df.if_flags = 0;
867 flags |= XFS_ILOG_DEV;
868 break;
869 case S_IFREG:
870 case S_IFDIR:
871 if (pip && (pip->i_d.di_flags & XFS_DIFLAG_ANY)) {
872 uint di_flags = 0;
873
874 if (S_ISDIR(mode)) {
875 if (pip->i_d.di_flags & XFS_DIFLAG_RTINHERIT)
876 di_flags |= XFS_DIFLAG_RTINHERIT;
877 if (pip->i_d.di_flags & XFS_DIFLAG_EXTSZINHERIT) {
878 di_flags |= XFS_DIFLAG_EXTSZINHERIT;
879 ip->i_d.di_extsize = pip->i_d.di_extsize;
880 }
881 if (pip->i_d.di_flags & XFS_DIFLAG_PROJINHERIT)
882 di_flags |= XFS_DIFLAG_PROJINHERIT;
883 } else if (S_ISREG(mode)) {
884 if (pip->i_d.di_flags & XFS_DIFLAG_RTINHERIT)
885 di_flags |= XFS_DIFLAG_REALTIME;
886 if (pip->i_d.di_flags & XFS_DIFLAG_EXTSZINHERIT) {
887 di_flags |= XFS_DIFLAG_EXTSIZE;
888 ip->i_d.di_extsize = pip->i_d.di_extsize;
889 }
890 }
891 if ((pip->i_d.di_flags & XFS_DIFLAG_NOATIME) &&
892 xfs_inherit_noatime)
893 di_flags |= XFS_DIFLAG_NOATIME;
894 if ((pip->i_d.di_flags & XFS_DIFLAG_NODUMP) &&
895 xfs_inherit_nodump)
896 di_flags |= XFS_DIFLAG_NODUMP;
897 if ((pip->i_d.di_flags & XFS_DIFLAG_SYNC) &&
898 xfs_inherit_sync)
899 di_flags |= XFS_DIFLAG_SYNC;
900 if ((pip->i_d.di_flags & XFS_DIFLAG_NOSYMLINKS) &&
901 xfs_inherit_nosymlinks)
902 di_flags |= XFS_DIFLAG_NOSYMLINKS;
903 if ((pip->i_d.di_flags & XFS_DIFLAG_NODEFRAG) &&
904 xfs_inherit_nodefrag)
905 di_flags |= XFS_DIFLAG_NODEFRAG;
906 if (pip->i_d.di_flags & XFS_DIFLAG_FILESTREAM)
907 di_flags |= XFS_DIFLAG_FILESTREAM;
908
909 ip->i_d.di_flags |= di_flags;
910 }
911 if (pip &&
912 (pip->i_d.di_flags2 & XFS_DIFLAG2_ANY) &&
913 pip->i_d.di_version == 3 &&
914 ip->i_d.di_version == 3) {
915 uint64_t di_flags2 = 0;
916
917 if (pip->i_d.di_flags2 & XFS_DIFLAG2_COWEXTSIZE) {
918 di_flags2 |= XFS_DIFLAG2_COWEXTSIZE;
919 ip->i_d.di_cowextsize = pip->i_d.di_cowextsize;
920 }
921 if (pip->i_d.di_flags2 & XFS_DIFLAG2_DAX)
922 di_flags2 |= XFS_DIFLAG2_DAX;
923
924 ip->i_d.di_flags2 |= di_flags2;
925 }
926 /* FALLTHROUGH */
927 case S_IFLNK:
928 ip->i_d.di_format = XFS_DINODE_FMT_EXTENTS;
929 ip->i_df.if_flags = XFS_IFEXTENTS;
930 ip->i_df.if_bytes = ip->i_df.if_real_bytes = 0;
931 ip->i_df.if_u1.if_root = NULL;
932 break;
933 default:
934 ASSERT(0);
935 }
936 /*
937 * Attribute fork settings for new inode.
938 */
939 ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;
940 ip->i_d.di_anextents = 0;
941
942 /*
943 * Log the new values stuffed into the inode.
944 */
945 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
946 xfs_trans_log_inode(tp, ip, flags);
947
948 /* now that we have an i_mode we can setup the inode structure */
949 xfs_setup_inode(ip);
950
951 *ipp = ip;
952 return 0;
953}
954
955/*
956 * Allocates a new inode from disk and return a pointer to the
957 * incore copy. This routine will internally commit the current
958 * transaction and allocate a new one if the Space Manager needed
959 * to do an allocation to replenish the inode free-list.
960 *
961 * This routine is designed to be called from xfs_create and
962 * xfs_create_dir.
963 *
964 */
965int
966xfs_dir_ialloc(
967 xfs_trans_t **tpp, /* input: current transaction;
968 output: may be a new transaction. */
969 xfs_inode_t *dp, /* directory within whose allocate
970 the inode. */
971 umode_t mode,
972 xfs_nlink_t nlink,
973 dev_t rdev,
974 prid_t prid, /* project id */
975 xfs_inode_t **ipp) /* pointer to inode; it will be
976 locked. */
977{
978 xfs_trans_t *tp;
979 xfs_inode_t *ip;
980 xfs_buf_t *ialloc_context = NULL;
981 int code;
982 void *dqinfo;
983 uint tflags;
984
985 tp = *tpp;
986 ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
987
988 /*
989 * xfs_ialloc will return a pointer to an incore inode if
990 * the Space Manager has an available inode on the free
991 * list. Otherwise, it will do an allocation and replenish
992 * the freelist. Since we can only do one allocation per
993 * transaction without deadlocks, we will need to commit the
994 * current transaction and start a new one. We will then
995 * need to call xfs_ialloc again to get the inode.
996 *
997 * If xfs_ialloc did an allocation to replenish the freelist,
998 * it returns the bp containing the head of the freelist as
999 * ialloc_context. We will hold a lock on it across the
1000 * transaction commit so that no other process can steal
1001 * the inode(s) that we've just allocated.
1002 */
1003 code = xfs_ialloc(tp, dp, mode, nlink, rdev, prid, &ialloc_context,
1004 &ip);
1005
1006 /*
1007 * Return an error if we were unable to allocate a new inode.
1008 * This should only happen if we run out of space on disk or
1009 * encounter a disk error.
1010 */
1011 if (code) {
1012 *ipp = NULL;
1013 return code;
1014 }
1015 if (!ialloc_context && !ip) {
1016 *ipp = NULL;
1017 return -ENOSPC;
1018 }
1019
1020 /*
1021 * If the AGI buffer is non-NULL, then we were unable to get an
1022 * inode in one operation. We need to commit the current
1023 * transaction and call xfs_ialloc() again. It is guaranteed
1024 * to succeed the second time.
1025 */
1026 if (ialloc_context) {
1027 /*
1028 * Normally, xfs_trans_commit releases all the locks.
1029 * We call bhold to hang on to the ialloc_context across
1030 * the commit. Holding this buffer prevents any other
1031 * processes from doing any allocations in this
1032 * allocation group.
1033 */
1034 xfs_trans_bhold(tp, ialloc_context);
1035
1036 /*
1037 * We want the quota changes to be associated with the next
1038 * transaction, NOT this one. So, detach the dqinfo from this
1039 * and attach it to the next transaction.
1040 */
1041 dqinfo = NULL;
1042 tflags = 0;
1043 if (tp->t_dqinfo) {
1044 dqinfo = (void *)tp->t_dqinfo;
1045 tp->t_dqinfo = NULL;
1046 tflags = tp->t_flags & XFS_TRANS_DQ_DIRTY;
1047 tp->t_flags &= ~(XFS_TRANS_DQ_DIRTY);
1048 }
1049
1050 code = xfs_trans_roll(&tp);
1051
1052 /*
1053 * Re-attach the quota info that we detached from prev trx.
1054 */
1055 if (dqinfo) {
1056 tp->t_dqinfo = dqinfo;
1057 tp->t_flags |= tflags;
1058 }
1059
1060 if (code) {
1061 xfs_buf_relse(ialloc_context);
1062 *tpp = tp;
1063 *ipp = NULL;
1064 return code;
1065 }
1066 xfs_trans_bjoin(tp, ialloc_context);
1067
1068 /*
1069 * Call ialloc again. Since we've locked out all
1070 * other allocations in this allocation group,
1071 * this call should always succeed.
1072 */
1073 code = xfs_ialloc(tp, dp, mode, nlink, rdev, prid,
1074 &ialloc_context, &ip);
1075
1076 /*
1077 * If we get an error at this point, return to the caller
1078 * so that the current transaction can be aborted.
1079 */
1080 if (code) {
1081 *tpp = tp;
1082 *ipp = NULL;
1083 return code;
1084 }
1085 ASSERT(!ialloc_context && ip);
1086
1087 }
1088
1089 *ipp = ip;
1090 *tpp = tp;
1091
1092 return 0;
1093}
1094
1095/*
1096 * Decrement the link count on an inode & log the change. If this causes the
1097 * link count to go to zero, move the inode to AGI unlinked list so that it can
1098 * be freed when the last active reference goes away via xfs_inactive().
1099 */
1100static int /* error */
1101xfs_droplink(
1102 xfs_trans_t *tp,
1103 xfs_inode_t *ip)
1104{
1105 xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
1106
1107 drop_nlink(VFS_I(ip));
1108 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1109
1110 if (VFS_I(ip)->i_nlink)
1111 return 0;
1112
1113 return xfs_iunlink(tp, ip);
1114}
1115
1116/*
1117 * Increment the link count on an inode & log the change.
1118 */
1119static int
1120xfs_bumplink(
1121 xfs_trans_t *tp,
1122 xfs_inode_t *ip)
1123{
1124 xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
1125
1126 ASSERT(ip->i_d.di_version > 1);
1127 inc_nlink(VFS_I(ip));
1128 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1129 return 0;
1130}
1131
1132int
1133xfs_create(
1134 xfs_inode_t *dp,
1135 struct xfs_name *name,
1136 umode_t mode,
1137 dev_t rdev,
1138 xfs_inode_t **ipp)
1139{
1140 int is_dir = S_ISDIR(mode);
1141 struct xfs_mount *mp = dp->i_mount;
1142 struct xfs_inode *ip = NULL;
1143 struct xfs_trans *tp = NULL;
1144 int error;
1145 struct xfs_defer_ops dfops;
1146 xfs_fsblock_t first_block;
1147 bool unlock_dp_on_error = false;
1148 prid_t prid;
1149 struct xfs_dquot *udqp = NULL;
1150 struct xfs_dquot *gdqp = NULL;
1151 struct xfs_dquot *pdqp = NULL;
1152 struct xfs_trans_res *tres;
1153 uint resblks;
1154
1155 trace_xfs_create(dp, name);
1156
1157 if (XFS_FORCED_SHUTDOWN(mp))
1158 return -EIO;
1159
1160 prid = xfs_get_initial_prid(dp);
1161
1162 /*
1163 * Make sure that we have allocated dquot(s) on disk.
1164 */
1165 error = xfs_qm_vop_dqalloc(dp, xfs_kuid_to_uid(current_fsuid()),
1166 xfs_kgid_to_gid(current_fsgid()), prid,
1167 XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
1168 &udqp, &gdqp, &pdqp);
1169 if (error)
1170 return error;
1171
1172 if (is_dir) {
1173 resblks = XFS_MKDIR_SPACE_RES(mp, name->len);
1174 tres = &M_RES(mp)->tr_mkdir;
1175 } else {
1176 resblks = XFS_CREATE_SPACE_RES(mp, name->len);
1177 tres = &M_RES(mp)->tr_create;
1178 }
1179
1180 /*
1181 * Initially assume that the file does not exist and
1182 * reserve the resources for that case. If that is not
1183 * the case we'll drop the one we have and get a more
1184 * appropriate transaction later.
1185 */
1186 error = xfs_trans_alloc(mp, tres, resblks, 0, 0, &tp);
1187 if (error == -ENOSPC) {
1188 /* flush outstanding delalloc blocks and retry */
1189 xfs_flush_inodes(mp);
1190 error = xfs_trans_alloc(mp, tres, resblks, 0, 0, &tp);
1191 }
1192 if (error)
1193 goto out_release_inode;
1194
1195 xfs_ilock(dp, XFS_ILOCK_EXCL | XFS_ILOCK_PARENT);
1196 unlock_dp_on_error = true;
1197
1198 xfs_defer_init(&dfops, &first_block);
1199
1200 /*
1201 * Reserve disk quota and the inode.
1202 */
1203 error = xfs_trans_reserve_quota(tp, mp, udqp, gdqp,
1204 pdqp, resblks, 1, 0);
1205 if (error)
1206 goto out_trans_cancel;
1207
1208 /*
1209 * A newly created regular or special file just has one directory
1210 * entry pointing to them, but a directory also the "." entry
1211 * pointing to itself.
1212 */
1213 error = xfs_dir_ialloc(&tp, dp, mode, is_dir ? 2 : 1, rdev, prid, &ip);
1214 if (error)
1215 goto out_trans_cancel;
1216
1217 /*
1218 * Now we join the directory inode to the transaction. We do not do it
1219 * earlier because xfs_dir_ialloc might commit the previous transaction
1220 * (and release all the locks). An error from here on will result in
1221 * the transaction cancel unlocking dp so don't do it explicitly in the
1222 * error path.
1223 */
1224 xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
1225 unlock_dp_on_error = false;
1226
1227 error = xfs_dir_createname(tp, dp, name, ip->i_ino,
1228 &first_block, &dfops, resblks ?
1229 resblks - XFS_IALLOC_SPACE_RES(mp) : 0);
1230 if (error) {
1231 ASSERT(error != -ENOSPC);
1232 goto out_trans_cancel;
1233 }
1234 xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1235 xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
1236
1237 if (is_dir) {
1238 error = xfs_dir_init(tp, ip, dp);
1239 if (error)
1240 goto out_bmap_cancel;
1241
1242 error = xfs_bumplink(tp, dp);
1243 if (error)
1244 goto out_bmap_cancel;
1245 }
1246
1247 /*
1248 * If this is a synchronous mount, make sure that the
1249 * create transaction goes to disk before returning to
1250 * the user.
1251 */
1252 if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
1253 xfs_trans_set_sync(tp);
1254
1255 /*
1256 * Attach the dquot(s) to the inodes and modify them incore.
1257 * These ids of the inode couldn't have changed since the new
1258 * inode has been locked ever since it was created.
1259 */
1260 xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp, pdqp);
1261
1262 error = xfs_defer_finish(&tp, &dfops);
1263 if (error)
1264 goto out_bmap_cancel;
1265
1266 error = xfs_trans_commit(tp);
1267 if (error)
1268 goto out_release_inode;
1269
1270 xfs_qm_dqrele(udqp);
1271 xfs_qm_dqrele(gdqp);
1272 xfs_qm_dqrele(pdqp);
1273
1274 *ipp = ip;
1275 return 0;
1276
1277 out_bmap_cancel:
1278 xfs_defer_cancel(&dfops);
1279 out_trans_cancel:
1280 xfs_trans_cancel(tp);
1281 out_release_inode:
1282 /*
1283 * Wait until after the current transaction is aborted to finish the
1284 * setup of the inode and release the inode. This prevents recursive
1285 * transactions and deadlocks from xfs_inactive.
1286 */
1287 if (ip) {
1288 xfs_finish_inode_setup(ip);
1289 IRELE(ip);
1290 }
1291
1292 xfs_qm_dqrele(udqp);
1293 xfs_qm_dqrele(gdqp);
1294 xfs_qm_dqrele(pdqp);
1295
1296 if (unlock_dp_on_error)
1297 xfs_iunlock(dp, XFS_ILOCK_EXCL);
1298 return error;
1299}
1300
1301int
1302xfs_create_tmpfile(
1303 struct xfs_inode *dp,
1304 umode_t mode,
1305 struct xfs_inode **ipp)
1306{
1307 struct xfs_mount *mp = dp->i_mount;
1308 struct xfs_inode *ip = NULL;
1309 struct xfs_trans *tp = NULL;
1310 int error;
1311 prid_t prid;
1312 struct xfs_dquot *udqp = NULL;
1313 struct xfs_dquot *gdqp = NULL;
1314 struct xfs_dquot *pdqp = NULL;
1315 struct xfs_trans_res *tres;
1316 uint resblks;
1317
1318 if (XFS_FORCED_SHUTDOWN(mp))
1319 return -EIO;
1320
1321 prid = xfs_get_initial_prid(dp);
1322
1323 /*
1324 * Make sure that we have allocated dquot(s) on disk.
1325 */
1326 error = xfs_qm_vop_dqalloc(dp, xfs_kuid_to_uid(current_fsuid()),
1327 xfs_kgid_to_gid(current_fsgid()), prid,
1328 XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
1329 &udqp, &gdqp, &pdqp);
1330 if (error)
1331 return error;
1332
1333 resblks = XFS_IALLOC_SPACE_RES(mp);
1334 tres = &M_RES(mp)->tr_create_tmpfile;
1335
1336 error = xfs_trans_alloc(mp, tres, resblks, 0, 0, &tp);
1337 if (error)
1338 goto out_release_inode;
1339
1340 error = xfs_trans_reserve_quota(tp, mp, udqp, gdqp,
1341 pdqp, resblks, 1, 0);
1342 if (error)
1343 goto out_trans_cancel;
1344
1345 error = xfs_dir_ialloc(&tp, dp, mode, 1, 0, prid, &ip);
1346 if (error)
1347 goto out_trans_cancel;
1348
1349 if (mp->m_flags & XFS_MOUNT_WSYNC)
1350 xfs_trans_set_sync(tp);
1351
1352 /*
1353 * Attach the dquot(s) to the inodes and modify them incore.
1354 * These ids of the inode couldn't have changed since the new
1355 * inode has been locked ever since it was created.
1356 */
1357 xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp, pdqp);
1358
1359 error = xfs_iunlink(tp, ip);
1360 if (error)
1361 goto out_trans_cancel;
1362
1363 error = xfs_trans_commit(tp);
1364 if (error)
1365 goto out_release_inode;
1366
1367 xfs_qm_dqrele(udqp);
1368 xfs_qm_dqrele(gdqp);
1369 xfs_qm_dqrele(pdqp);
1370
1371 *ipp = ip;
1372 return 0;
1373
1374 out_trans_cancel:
1375 xfs_trans_cancel(tp);
1376 out_release_inode:
1377 /*
1378 * Wait until after the current transaction is aborted to finish the
1379 * setup of the inode and release the inode. This prevents recursive
1380 * transactions and deadlocks from xfs_inactive.
1381 */
1382 if (ip) {
1383 xfs_finish_inode_setup(ip);
1384 IRELE(ip);
1385 }
1386
1387 xfs_qm_dqrele(udqp);
1388 xfs_qm_dqrele(gdqp);
1389 xfs_qm_dqrele(pdqp);
1390
1391 return error;
1392}
1393
1394int
1395xfs_link(
1396 xfs_inode_t *tdp,
1397 xfs_inode_t *sip,
1398 struct xfs_name *target_name)
1399{
1400 xfs_mount_t *mp = tdp->i_mount;
1401 xfs_trans_t *tp;
1402 int error;
1403 struct xfs_defer_ops dfops;
1404 xfs_fsblock_t first_block;
1405 int resblks;
1406
1407 trace_xfs_link(tdp, target_name);
1408
1409 ASSERT(!S_ISDIR(VFS_I(sip)->i_mode));
1410
1411 if (XFS_FORCED_SHUTDOWN(mp))
1412 return -EIO;
1413
1414 error = xfs_qm_dqattach(sip, 0);
1415 if (error)
1416 goto std_return;
1417
1418 error = xfs_qm_dqattach(tdp, 0);
1419 if (error)
1420 goto std_return;
1421
1422 resblks = XFS_LINK_SPACE_RES(mp, target_name->len);
1423 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_link, resblks, 0, 0, &tp);
1424 if (error == -ENOSPC) {
1425 resblks = 0;
1426 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_link, 0, 0, 0, &tp);
1427 }
1428 if (error)
1429 goto std_return;
1430
1431 xfs_lock_two_inodes(sip, XFS_ILOCK_EXCL, tdp, XFS_ILOCK_EXCL);
1432
1433 xfs_trans_ijoin(tp, sip, XFS_ILOCK_EXCL);
1434 xfs_trans_ijoin(tp, tdp, XFS_ILOCK_EXCL);
1435
1436 /*
1437 * If we are using project inheritance, we only allow hard link
1438 * creation in our tree when the project IDs are the same; else
1439 * the tree quota mechanism could be circumvented.
1440 */
1441 if (unlikely((tdp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) &&
1442 (xfs_get_projid(tdp) != xfs_get_projid(sip)))) {
1443 error = -EXDEV;
1444 goto error_return;
1445 }
1446
1447 if (!resblks) {
1448 error = xfs_dir_canenter(tp, tdp, target_name);
1449 if (error)
1450 goto error_return;
1451 }
1452
1453 xfs_defer_init(&dfops, &first_block);
1454
1455 /*
1456 * Handle initial link state of O_TMPFILE inode
1457 */
1458 if (VFS_I(sip)->i_nlink == 0) {
1459 error = xfs_iunlink_remove(tp, sip);
1460 if (error)
1461 goto error_return;
1462 }
1463
1464 error = xfs_dir_createname(tp, tdp, target_name, sip->i_ino,
1465 &first_block, &dfops, resblks);
1466 if (error)
1467 goto error_return;
1468 xfs_trans_ichgtime(tp, tdp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1469 xfs_trans_log_inode(tp, tdp, XFS_ILOG_CORE);
1470
1471 error = xfs_bumplink(tp, sip);
1472 if (error)
1473 goto error_return;
1474
1475 /*
1476 * If this is a synchronous mount, make sure that the
1477 * link transaction goes to disk before returning to
1478 * the user.
1479 */
1480 if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
1481 xfs_trans_set_sync(tp);
1482
1483 error = xfs_defer_finish(&tp, &dfops);
1484 if (error) {
1485 xfs_defer_cancel(&dfops);
1486 goto error_return;
1487 }
1488
1489 return xfs_trans_commit(tp);
1490
1491 error_return:
1492 xfs_trans_cancel(tp);
1493 std_return:
1494 return error;
1495}
1496
1497/* Clear the reflink flag and the cowblocks tag if possible. */
1498static void
1499xfs_itruncate_clear_reflink_flags(
1500 struct xfs_inode *ip)
1501{
1502 struct xfs_ifork *dfork;
1503 struct xfs_ifork *cfork;
1504
1505 if (!xfs_is_reflink_inode(ip))
1506 return;
1507 dfork = XFS_IFORK_PTR(ip, XFS_DATA_FORK);
1508 cfork = XFS_IFORK_PTR(ip, XFS_COW_FORK);
1509 if (dfork->if_bytes == 0 && cfork->if_bytes == 0)
1510 ip->i_d.di_flags2 &= ~XFS_DIFLAG2_REFLINK;
1511 if (cfork->if_bytes == 0)
1512 xfs_inode_clear_cowblocks_tag(ip);
1513}
1514
1515/*
1516 * Free up the underlying blocks past new_size. The new size must be smaller
1517 * than the current size. This routine can be used both for the attribute and
1518 * data fork, and does not modify the inode size, which is left to the caller.
1519 *
1520 * The transaction passed to this routine must have made a permanent log
1521 * reservation of at least XFS_ITRUNCATE_LOG_RES. This routine may commit the
1522 * given transaction and start new ones, so make sure everything involved in
1523 * the transaction is tidy before calling here. Some transaction will be
1524 * returned to the caller to be committed. The incoming transaction must
1525 * already include the inode, and both inode locks must be held exclusively.
1526 * The inode must also be "held" within the transaction. On return the inode
1527 * will be "held" within the returned transaction. This routine does NOT
1528 * require any disk space to be reserved for it within the transaction.
1529 *
1530 * If we get an error, we must return with the inode locked and linked into the
1531 * current transaction. This keeps things simple for the higher level code,
1532 * because it always knows that the inode is locked and held in the transaction
1533 * that returns to it whether errors occur or not. We don't mark the inode
1534 * dirty on error so that transactions can be easily aborted if possible.
1535 */
1536int
1537xfs_itruncate_extents(
1538 struct xfs_trans **tpp,
1539 struct xfs_inode *ip,
1540 int whichfork,
1541 xfs_fsize_t new_size)
1542{
1543 struct xfs_mount *mp = ip->i_mount;
1544 struct xfs_trans *tp = *tpp;
1545 struct xfs_defer_ops dfops;
1546 xfs_fsblock_t first_block;
1547 xfs_fileoff_t first_unmap_block;
1548 xfs_fileoff_t last_block;
1549 xfs_filblks_t unmap_len;
1550 int error = 0;
1551 int done = 0;
1552
1553 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
1554 ASSERT(!atomic_read(&VFS_I(ip)->i_count) ||
1555 xfs_isilocked(ip, XFS_IOLOCK_EXCL));
1556 ASSERT(new_size <= XFS_ISIZE(ip));
1557 ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
1558 ASSERT(ip->i_itemp != NULL);
1559 ASSERT(ip->i_itemp->ili_lock_flags == 0);
1560 ASSERT(!XFS_NOT_DQATTACHED(mp, ip));
1561
1562 trace_xfs_itruncate_extents_start(ip, new_size);
1563
1564 /*
1565 * Since it is possible for space to become allocated beyond
1566 * the end of the file (in a crash where the space is allocated
1567 * but the inode size is not yet updated), simply remove any
1568 * blocks which show up between the new EOF and the maximum
1569 * possible file size. If the first block to be removed is
1570 * beyond the maximum file size (ie it is the same as last_block),
1571 * then there is nothing to do.
1572 */
1573 first_unmap_block = XFS_B_TO_FSB(mp, (xfs_ufsize_t)new_size);
1574 last_block = XFS_B_TO_FSB(mp, mp->m_super->s_maxbytes);
1575 if (first_unmap_block == last_block)
1576 return 0;
1577
1578 ASSERT(first_unmap_block < last_block);
1579 unmap_len = last_block - first_unmap_block + 1;
1580 while (!done) {
1581 xfs_defer_init(&dfops, &first_block);
1582 error = xfs_bunmapi(tp, ip,
1583 first_unmap_block, unmap_len,
1584 xfs_bmapi_aflag(whichfork),
1585 XFS_ITRUNC_MAX_EXTENTS,
1586 &first_block, &dfops,
1587 &done);
1588 if (error)
1589 goto out_bmap_cancel;
1590
1591 /*
1592 * Duplicate the transaction that has the permanent
1593 * reservation and commit the old transaction.
1594 */
1595 xfs_defer_ijoin(&dfops, ip);
1596 error = xfs_defer_finish(&tp, &dfops);
1597 if (error)
1598 goto out_bmap_cancel;
1599
1600 error = xfs_trans_roll_inode(&tp, ip);
1601 if (error)
1602 goto out;
1603 }
1604
1605 if (whichfork == XFS_DATA_FORK) {
1606 /* Remove all pending CoW reservations. */
1607 error = xfs_reflink_cancel_cow_blocks(ip, &tp,
1608 first_unmap_block, last_block, true);
1609 if (error)
1610 goto out;
1611
1612 xfs_itruncate_clear_reflink_flags(ip);
1613 }
1614
1615 /*
1616 * Always re-log the inode so that our permanent transaction can keep
1617 * on rolling it forward in the log.
1618 */
1619 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1620
1621 trace_xfs_itruncate_extents_end(ip, new_size);
1622
1623out:
1624 *tpp = tp;
1625 return error;
1626out_bmap_cancel:
1627 /*
1628 * If the bunmapi call encounters an error, return to the caller where
1629 * the transaction can be properly aborted. We just need to make sure
1630 * we're not holding any resources that we were not when we came in.
1631 */
1632 xfs_defer_cancel(&dfops);
1633 goto out;
1634}
1635
1636int
1637xfs_release(
1638 xfs_inode_t *ip)
1639{
1640 xfs_mount_t *mp = ip->i_mount;
1641 int error;
1642
1643 if (!S_ISREG(VFS_I(ip)->i_mode) || (VFS_I(ip)->i_mode == 0))
1644 return 0;
1645
1646 /* If this is a read-only mount, don't do this (would generate I/O) */
1647 if (mp->m_flags & XFS_MOUNT_RDONLY)
1648 return 0;
1649
1650 if (!XFS_FORCED_SHUTDOWN(mp)) {
1651 int truncated;
1652
1653 /*
1654 * If we previously truncated this file and removed old data
1655 * in the process, we want to initiate "early" writeout on
1656 * the last close. This is an attempt to combat the notorious
1657 * NULL files problem which is particularly noticeable from a
1658 * truncate down, buffered (re-)write (delalloc), followed by
1659 * a crash. What we are effectively doing here is
1660 * significantly reducing the time window where we'd otherwise
1661 * be exposed to that problem.
1662 */
1663 truncated = xfs_iflags_test_and_clear(ip, XFS_ITRUNCATED);
1664 if (truncated) {
1665 xfs_iflags_clear(ip, XFS_IDIRTY_RELEASE);
1666 if (ip->i_delayed_blks > 0) {
1667 error = filemap_flush(VFS_I(ip)->i_mapping);
1668 if (error)
1669 return error;
1670 }
1671 }
1672 }
1673
1674 if (VFS_I(ip)->i_nlink == 0)
1675 return 0;
1676
1677 if (xfs_can_free_eofblocks(ip, false)) {
1678
1679 /*
1680 * Check if the inode is being opened, written and closed
1681 * frequently and we have delayed allocation blocks outstanding
1682 * (e.g. streaming writes from the NFS server), truncating the
1683 * blocks past EOF will cause fragmentation to occur.
1684 *
1685 * In this case don't do the truncation, but we have to be
1686 * careful how we detect this case. Blocks beyond EOF show up as
1687 * i_delayed_blks even when the inode is clean, so we need to
1688 * truncate them away first before checking for a dirty release.
1689 * Hence on the first dirty close we will still remove the
1690 * speculative allocation, but after that we will leave it in
1691 * place.
1692 */
1693 if (xfs_iflags_test(ip, XFS_IDIRTY_RELEASE))
1694 return 0;
1695 /*
1696 * If we can't get the iolock just skip truncating the blocks
1697 * past EOF because we could deadlock with the mmap_sem
1698 * otherwise. We'll get another chance to drop them once the
1699 * last reference to the inode is dropped, so we'll never leak
1700 * blocks permanently.
1701 */
1702 if (xfs_ilock_nowait(ip, XFS_IOLOCK_EXCL)) {
1703 error = xfs_free_eofblocks(ip);
1704 xfs_iunlock(ip, XFS_IOLOCK_EXCL);
1705 if (error)
1706 return error;
1707 }
1708
1709 /* delalloc blocks after truncation means it really is dirty */
1710 if (ip->i_delayed_blks)
1711 xfs_iflags_set(ip, XFS_IDIRTY_RELEASE);
1712 }
1713 return 0;
1714}
1715
1716/*
1717 * xfs_inactive_truncate
1718 *
1719 * Called to perform a truncate when an inode becomes unlinked.
1720 */
1721STATIC int
1722xfs_inactive_truncate(
1723 struct xfs_inode *ip)
1724{
1725 struct xfs_mount *mp = ip->i_mount;
1726 struct xfs_trans *tp;
1727 int error;
1728
1729 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, 0, 0, 0, &tp);
1730 if (error) {
1731 ASSERT(XFS_FORCED_SHUTDOWN(mp));
1732 return error;
1733 }
1734
1735 xfs_ilock(ip, XFS_ILOCK_EXCL);
1736 xfs_trans_ijoin(tp, ip, 0);
1737
1738 /*
1739 * Log the inode size first to prevent stale data exposure in the event
1740 * of a system crash before the truncate completes. See the related
1741 * comment in xfs_vn_setattr_size() for details.
1742 */
1743 ip->i_d.di_size = 0;
1744 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1745
1746 error = xfs_itruncate_extents(&tp, ip, XFS_DATA_FORK, 0);
1747 if (error)
1748 goto error_trans_cancel;
1749
1750 ASSERT(ip->i_d.di_nextents == 0);
1751
1752 error = xfs_trans_commit(tp);
1753 if (error)
1754 goto error_unlock;
1755
1756 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1757 return 0;
1758
1759error_trans_cancel:
1760 xfs_trans_cancel(tp);
1761error_unlock:
1762 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1763 return error;
1764}
1765
1766/*
1767 * xfs_inactive_ifree()
1768 *
1769 * Perform the inode free when an inode is unlinked.
1770 */
1771STATIC int
1772xfs_inactive_ifree(
1773 struct xfs_inode *ip)
1774{
1775 struct xfs_defer_ops dfops;
1776 xfs_fsblock_t first_block;
1777 struct xfs_mount *mp = ip->i_mount;
1778 struct xfs_trans *tp;
1779 int error;
1780
1781 /*
1782 * We try to use a per-AG reservation for any block needed by the finobt
1783 * tree, but as the finobt feature predates the per-AG reservation
1784 * support a degraded file system might not have enough space for the
1785 * reservation at mount time. In that case try to dip into the reserved
1786 * pool and pray.
1787 *
1788 * Send a warning if the reservation does happen to fail, as the inode
1789 * now remains allocated and sits on the unlinked list until the fs is
1790 * repaired.
1791 */
1792 if (unlikely(mp->m_inotbt_nores)) {
1793 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ifree,
1794 XFS_IFREE_SPACE_RES(mp), 0, XFS_TRANS_RESERVE,
1795 &tp);
1796 } else {
1797 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ifree, 0, 0, 0, &tp);
1798 }
1799 if (error) {
1800 if (error == -ENOSPC) {
1801 xfs_warn_ratelimited(mp,
1802 "Failed to remove inode(s) from unlinked list. "
1803 "Please free space, unmount and run xfs_repair.");
1804 } else {
1805 ASSERT(XFS_FORCED_SHUTDOWN(mp));
1806 }
1807 return error;
1808 }
1809
1810 xfs_ilock(ip, XFS_ILOCK_EXCL);
1811 xfs_trans_ijoin(tp, ip, 0);
1812
1813 xfs_defer_init(&dfops, &first_block);
1814 error = xfs_ifree(tp, ip, &dfops);
1815 if (error) {
1816 /*
1817 * If we fail to free the inode, shut down. The cancel
1818 * might do that, we need to make sure. Otherwise the
1819 * inode might be lost for a long time or forever.
1820 */
1821 if (!XFS_FORCED_SHUTDOWN(mp)) {
1822 xfs_notice(mp, "%s: xfs_ifree returned error %d",
1823 __func__, error);
1824 xfs_force_shutdown(mp, SHUTDOWN_META_IO_ERROR);
1825 }
1826 xfs_trans_cancel(tp);
1827 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1828 return error;
1829 }
1830
1831 /*
1832 * Credit the quota account(s). The inode is gone.
1833 */
1834 xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_ICOUNT, -1);
1835
1836 /*
1837 * Just ignore errors at this point. There is nothing we can do except
1838 * to try to keep going. Make sure it's not a silent error.
1839 */
1840 error = xfs_defer_finish(&tp, &dfops);
1841 if (error) {
1842 xfs_notice(mp, "%s: xfs_defer_finish returned error %d",
1843 __func__, error);
1844 xfs_defer_cancel(&dfops);
1845 }
1846 error = xfs_trans_commit(tp);
1847 if (error)
1848 xfs_notice(mp, "%s: xfs_trans_commit returned error %d",
1849 __func__, error);
1850
1851 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1852 return 0;
1853}
1854
1855/*
1856 * xfs_inactive
1857 *
1858 * This is called when the vnode reference count for the vnode
1859 * goes to zero. If the file has been unlinked, then it must
1860 * now be truncated. Also, we clear all of the read-ahead state
1861 * kept for the inode here since the file is now closed.
1862 */
1863void
1864xfs_inactive(
1865 xfs_inode_t *ip)
1866{
1867 struct xfs_mount *mp;
1868 struct xfs_ifork *cow_ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK);
1869 int error;
1870 int truncate = 0;
1871
1872 /*
1873 * If the inode is already free, then there can be nothing
1874 * to clean up here.
1875 */
1876 if (VFS_I(ip)->i_mode == 0) {
1877 ASSERT(ip->i_df.if_real_bytes == 0);
1878 ASSERT(ip->i_df.if_broot_bytes == 0);
1879 return;
1880 }
1881
1882 mp = ip->i_mount;
1883 ASSERT(!xfs_iflags_test(ip, XFS_IRECOVERY));
1884
1885 /* If this is a read-only mount, don't do this (would generate I/O) */
1886 if (mp->m_flags & XFS_MOUNT_RDONLY)
1887 return;
1888
1889 /* Try to clean out the cow blocks if there are any. */
1890 if (xfs_is_reflink_inode(ip) && cow_ifp->if_bytes > 0)
1891 xfs_reflink_cancel_cow_range(ip, 0, NULLFILEOFF, true);
1892
1893 if (VFS_I(ip)->i_nlink != 0) {
1894 /*
1895 * force is true because we are evicting an inode from the
1896 * cache. Post-eof blocks must be freed, lest we end up with
1897 * broken free space accounting.
1898 *
1899 * Note: don't bother with iolock here since lockdep complains
1900 * about acquiring it in reclaim context. We have the only
1901 * reference to the inode at this point anyways.
1902 */
1903 if (xfs_can_free_eofblocks(ip, true))
1904 xfs_free_eofblocks(ip);
1905
1906 return;
1907 }
1908
1909 if (S_ISREG(VFS_I(ip)->i_mode) &&
1910 (ip->i_d.di_size != 0 || XFS_ISIZE(ip) != 0 ||
1911 ip->i_d.di_nextents > 0 || ip->i_delayed_blks > 0))
1912 truncate = 1;
1913
1914 error = xfs_qm_dqattach(ip, 0);
1915 if (error)
1916 return;
1917
1918 if (S_ISLNK(VFS_I(ip)->i_mode))
1919 error = xfs_inactive_symlink(ip);
1920 else if (truncate)
1921 error = xfs_inactive_truncate(ip);
1922 if (error)
1923 return;
1924
1925 /*
1926 * If there are attributes associated with the file then blow them away
1927 * now. The code calls a routine that recursively deconstructs the
1928 * attribute fork. If also blows away the in-core attribute fork.
1929 */
1930 if (XFS_IFORK_Q(ip)) {
1931 error = xfs_attr_inactive(ip);
1932 if (error)
1933 return;
1934 }
1935
1936 ASSERT(!ip->i_afp);
1937 ASSERT(ip->i_d.di_anextents == 0);
1938 ASSERT(ip->i_d.di_forkoff == 0);
1939
1940 /*
1941 * Free the inode.
1942 */
1943 error = xfs_inactive_ifree(ip);
1944 if (error)
1945 return;
1946
1947 /*
1948 * Release the dquots held by inode, if any.
1949 */
1950 xfs_qm_dqdetach(ip);
1951}
1952
1953/*
1954 * This is called when the inode's link count goes to 0 or we are creating a
1955 * tmpfile via O_TMPFILE. In the case of a tmpfile, @ignore_linkcount will be
1956 * set to true as the link count is dropped to zero by the VFS after we've
1957 * created the file successfully, so we have to add it to the unlinked list
1958 * while the link count is non-zero.
1959 *
1960 * We place the on-disk inode on a list in the AGI. It will be pulled from this
1961 * list when the inode is freed.
1962 */
1963STATIC int
1964xfs_iunlink(
1965 struct xfs_trans *tp,
1966 struct xfs_inode *ip)
1967{
1968 xfs_mount_t *mp = tp->t_mountp;
1969 xfs_agi_t *agi;
1970 xfs_dinode_t *dip;
1971 xfs_buf_t *agibp;
1972 xfs_buf_t *ibp;
1973 xfs_agino_t agino;
1974 short bucket_index;
1975 int offset;
1976 int error;
1977
1978 ASSERT(VFS_I(ip)->i_mode != 0);
1979
1980 /*
1981 * Get the agi buffer first. It ensures lock ordering
1982 * on the list.
1983 */
1984 error = xfs_read_agi(mp, tp, XFS_INO_TO_AGNO(mp, ip->i_ino), &agibp);
1985 if (error)
1986 return error;
1987 agi = XFS_BUF_TO_AGI(agibp);
1988
1989 /*
1990 * Get the index into the agi hash table for the
1991 * list this inode will go on.
1992 */
1993 agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
1994 ASSERT(agino != 0);
1995 bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
1996 ASSERT(agi->agi_unlinked[bucket_index]);
1997 ASSERT(be32_to_cpu(agi->agi_unlinked[bucket_index]) != agino);
1998
1999 if (agi->agi_unlinked[bucket_index] != cpu_to_be32(NULLAGINO)) {
2000 /*
2001 * There is already another inode in the bucket we need
2002 * to add ourselves to. Add us at the front of the list.
2003 * Here we put the head pointer into our next pointer,
2004 * and then we fall through to point the head at us.
2005 */
2006 error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &ibp,
2007 0, 0);
2008 if (error)
2009 return error;
2010
2011 ASSERT(dip->di_next_unlinked == cpu_to_be32(NULLAGINO));
2012 dip->di_next_unlinked = agi->agi_unlinked[bucket_index];
2013 offset = ip->i_imap.im_boffset +
2014 offsetof(xfs_dinode_t, di_next_unlinked);
2015
2016 /* need to recalc the inode CRC if appropriate */
2017 xfs_dinode_calc_crc(mp, dip);
2018
2019 xfs_trans_inode_buf(tp, ibp);
2020 xfs_trans_log_buf(tp, ibp, offset,
2021 (offset + sizeof(xfs_agino_t) - 1));
2022 xfs_inobp_check(mp, ibp);
2023 }
2024
2025 /*
2026 * Point the bucket head pointer at the inode being inserted.
2027 */
2028 ASSERT(agino != 0);
2029 agi->agi_unlinked[bucket_index] = cpu_to_be32(agino);
2030 offset = offsetof(xfs_agi_t, agi_unlinked) +
2031 (sizeof(xfs_agino_t) * bucket_index);
2032 xfs_trans_log_buf(tp, agibp, offset,
2033 (offset + sizeof(xfs_agino_t) - 1));
2034 return 0;
2035}
2036
2037/*
2038 * Pull the on-disk inode from the AGI unlinked list.
2039 */
2040STATIC int
2041xfs_iunlink_remove(
2042 xfs_trans_t *tp,
2043 xfs_inode_t *ip)
2044{
2045 xfs_ino_t next_ino;
2046 xfs_mount_t *mp;
2047 xfs_agi_t *agi;
2048 xfs_dinode_t *dip;
2049 xfs_buf_t *agibp;
2050 xfs_buf_t *ibp;
2051 xfs_agnumber_t agno;
2052 xfs_agino_t agino;
2053 xfs_agino_t next_agino;
2054 xfs_buf_t *last_ibp;
2055 xfs_dinode_t *last_dip = NULL;
2056 short bucket_index;
2057 int offset, last_offset = 0;
2058 int error;
2059
2060 mp = tp->t_mountp;
2061 agno = XFS_INO_TO_AGNO(mp, ip->i_ino);
2062
2063 /*
2064 * Get the agi buffer first. It ensures lock ordering
2065 * on the list.
2066 */
2067 error = xfs_read_agi(mp, tp, agno, &agibp);
2068 if (error)
2069 return error;
2070
2071 agi = XFS_BUF_TO_AGI(agibp);
2072
2073 /*
2074 * Get the index into the agi hash table for the
2075 * list this inode will go on.
2076 */
2077 agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
2078 ASSERT(agino != 0);
2079 bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
2080 ASSERT(agi->agi_unlinked[bucket_index] != cpu_to_be32(NULLAGINO));
2081 ASSERT(agi->agi_unlinked[bucket_index]);
2082
2083 if (be32_to_cpu(agi->agi_unlinked[bucket_index]) == agino) {
2084 /*
2085 * We're at the head of the list. Get the inode's on-disk
2086 * buffer to see if there is anyone after us on the list.
2087 * Only modify our next pointer if it is not already NULLAGINO.
2088 * This saves us the overhead of dealing with the buffer when
2089 * there is no need to change it.
2090 */
2091 error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &ibp,
2092 0, 0);
2093 if (error) {
2094 xfs_warn(mp, "%s: xfs_imap_to_bp returned error %d.",
2095 __func__, error);
2096 return error;
2097 }
2098 next_agino = be32_to_cpu(dip->di_next_unlinked);
2099 ASSERT(next_agino != 0);
2100 if (next_agino != NULLAGINO) {
2101 dip->di_next_unlinked = cpu_to_be32(NULLAGINO);
2102 offset = ip->i_imap.im_boffset +
2103 offsetof(xfs_dinode_t, di_next_unlinked);
2104
2105 /* need to recalc the inode CRC if appropriate */
2106 xfs_dinode_calc_crc(mp, dip);
2107
2108 xfs_trans_inode_buf(tp, ibp);
2109 xfs_trans_log_buf(tp, ibp, offset,
2110 (offset + sizeof(xfs_agino_t) - 1));
2111 xfs_inobp_check(mp, ibp);
2112 } else {
2113 xfs_trans_brelse(tp, ibp);
2114 }
2115 /*
2116 * Point the bucket head pointer at the next inode.
2117 */
2118 ASSERT(next_agino != 0);
2119 ASSERT(next_agino != agino);
2120 agi->agi_unlinked[bucket_index] = cpu_to_be32(next_agino);
2121 offset = offsetof(xfs_agi_t, agi_unlinked) +
2122 (sizeof(xfs_agino_t) * bucket_index);
2123 xfs_trans_log_buf(tp, agibp, offset,
2124 (offset + sizeof(xfs_agino_t) - 1));
2125 } else {
2126 /*
2127 * We need to search the list for the inode being freed.
2128 */
2129 next_agino = be32_to_cpu(agi->agi_unlinked[bucket_index]);
2130 last_ibp = NULL;
2131 while (next_agino != agino) {
2132 struct xfs_imap imap;
2133
2134 if (last_ibp)
2135 xfs_trans_brelse(tp, last_ibp);
2136
2137 imap.im_blkno = 0;
2138 next_ino = XFS_AGINO_TO_INO(mp, agno, next_agino);
2139
2140 error = xfs_imap(mp, tp, next_ino, &imap, 0);
2141 if (error) {
2142 xfs_warn(mp,
2143 "%s: xfs_imap returned error %d.",
2144 __func__, error);
2145 return error;
2146 }
2147
2148 error = xfs_imap_to_bp(mp, tp, &imap, &last_dip,
2149 &last_ibp, 0, 0);
2150 if (error) {
2151 xfs_warn(mp,
2152 "%s: xfs_imap_to_bp returned error %d.",
2153 __func__, error);
2154 return error;
2155 }
2156
2157 last_offset = imap.im_boffset;
2158 next_agino = be32_to_cpu(last_dip->di_next_unlinked);
2159 ASSERT(next_agino != NULLAGINO);
2160 ASSERT(next_agino != 0);
2161 }
2162
2163 /*
2164 * Now last_ibp points to the buffer previous to us on the
2165 * unlinked list. Pull us from the list.
2166 */
2167 error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &ibp,
2168 0, 0);
2169 if (error) {
2170 xfs_warn(mp, "%s: xfs_imap_to_bp(2) returned error %d.",
2171 __func__, error);
2172 return error;
2173 }
2174 next_agino = be32_to_cpu(dip->di_next_unlinked);
2175 ASSERT(next_agino != 0);
2176 ASSERT(next_agino != agino);
2177 if (next_agino != NULLAGINO) {
2178 dip->di_next_unlinked = cpu_to_be32(NULLAGINO);
2179 offset = ip->i_imap.im_boffset +
2180 offsetof(xfs_dinode_t, di_next_unlinked);
2181
2182 /* need to recalc the inode CRC if appropriate */
2183 xfs_dinode_calc_crc(mp, dip);
2184
2185 xfs_trans_inode_buf(tp, ibp);
2186 xfs_trans_log_buf(tp, ibp, offset,
2187 (offset + sizeof(xfs_agino_t) - 1));
2188 xfs_inobp_check(mp, ibp);
2189 } else {
2190 xfs_trans_brelse(tp, ibp);
2191 }
2192 /*
2193 * Point the previous inode on the list to the next inode.
2194 */
2195 last_dip->di_next_unlinked = cpu_to_be32(next_agino);
2196 ASSERT(next_agino != 0);
2197 offset = last_offset + offsetof(xfs_dinode_t, di_next_unlinked);
2198
2199 /* need to recalc the inode CRC if appropriate */
2200 xfs_dinode_calc_crc(mp, last_dip);
2201
2202 xfs_trans_inode_buf(tp, last_ibp);
2203 xfs_trans_log_buf(tp, last_ibp, offset,
2204 (offset + sizeof(xfs_agino_t) - 1));
2205 xfs_inobp_check(mp, last_ibp);
2206 }
2207 return 0;
2208}
2209
2210/*
2211 * A big issue when freeing the inode cluster is that we _cannot_ skip any
2212 * inodes that are in memory - they all must be marked stale and attached to
2213 * the cluster buffer.
2214 */
2215STATIC int
2216xfs_ifree_cluster(
2217 xfs_inode_t *free_ip,
2218 xfs_trans_t *tp,
2219 struct xfs_icluster *xic)
2220{
2221 xfs_mount_t *mp = free_ip->i_mount;
2222 int blks_per_cluster;
2223 int inodes_per_cluster;
2224 int nbufs;
2225 int i, j;
2226 int ioffset;
2227 xfs_daddr_t blkno;
2228 xfs_buf_t *bp;
2229 xfs_inode_t *ip;
2230 xfs_inode_log_item_t *iip;
2231 struct xfs_log_item *lip;
2232 struct xfs_perag *pag;
2233 xfs_ino_t inum;
2234
2235 inum = xic->first_ino;
2236 pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, inum));
2237 blks_per_cluster = xfs_icluster_size_fsb(mp);
2238 inodes_per_cluster = blks_per_cluster << mp->m_sb.sb_inopblog;
2239 nbufs = mp->m_ialloc_blks / blks_per_cluster;
2240
2241 for (j = 0; j < nbufs; j++, inum += inodes_per_cluster) {
2242 /*
2243 * The allocation bitmap tells us which inodes of the chunk were
2244 * physically allocated. Skip the cluster if an inode falls into
2245 * a sparse region.
2246 */
2247 ioffset = inum - xic->first_ino;
2248 if ((xic->alloc & XFS_INOBT_MASK(ioffset)) == 0) {
2249 ASSERT(do_mod(ioffset, inodes_per_cluster) == 0);
2250 continue;
2251 }
2252
2253 blkno = XFS_AGB_TO_DADDR(mp, XFS_INO_TO_AGNO(mp, inum),
2254 XFS_INO_TO_AGBNO(mp, inum));
2255
2256 /*
2257 * We obtain and lock the backing buffer first in the process
2258 * here, as we have to ensure that any dirty inode that we
2259 * can't get the flush lock on is attached to the buffer.
2260 * If we scan the in-memory inodes first, then buffer IO can
2261 * complete before we get a lock on it, and hence we may fail
2262 * to mark all the active inodes on the buffer stale.
2263 */
2264 bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, blkno,
2265 mp->m_bsize * blks_per_cluster,
2266 XBF_UNMAPPED);
2267
2268 if (!bp)
2269 return -ENOMEM;
2270
2271 /*
2272 * This buffer may not have been correctly initialised as we
2273 * didn't read it from disk. That's not important because we are
2274 * only using to mark the buffer as stale in the log, and to
2275 * attach stale cached inodes on it. That means it will never be
2276 * dispatched for IO. If it is, we want to know about it, and we
2277 * want it to fail. We can acheive this by adding a write
2278 * verifier to the buffer.
2279 */
2280 bp->b_ops = &xfs_inode_buf_ops;
2281
2282 /*
2283 * Walk the inodes already attached to the buffer and mark them
2284 * stale. These will all have the flush locks held, so an
2285 * in-memory inode walk can't lock them. By marking them all
2286 * stale first, we will not attempt to lock them in the loop
2287 * below as the XFS_ISTALE flag will be set.
2288 */
2289 list_for_each_entry(lip, &bp->b_li_list, li_bio_list) {
2290 if (lip->li_type == XFS_LI_INODE) {
2291 iip = (xfs_inode_log_item_t *)lip;
2292 ASSERT(iip->ili_logged == 1);
2293 lip->li_cb = xfs_istale_done;
2294 xfs_trans_ail_copy_lsn(mp->m_ail,
2295 &iip->ili_flush_lsn,
2296 &iip->ili_item.li_lsn);
2297 xfs_iflags_set(iip->ili_inode, XFS_ISTALE);
2298 }
2299 }
2300
2301
2302 /*
2303 * For each inode in memory attempt to add it to the inode
2304 * buffer and set it up for being staled on buffer IO
2305 * completion. This is safe as we've locked out tail pushing
2306 * and flushing by locking the buffer.
2307 *
2308 * We have already marked every inode that was part of a
2309 * transaction stale above, which means there is no point in
2310 * even trying to lock them.
2311 */
2312 for (i = 0; i < inodes_per_cluster; i++) {
2313retry:
2314 rcu_read_lock();
2315 ip = radix_tree_lookup(&pag->pag_ici_root,
2316 XFS_INO_TO_AGINO(mp, (inum + i)));
2317
2318 /* Inode not in memory, nothing to do */
2319 if (!ip) {
2320 rcu_read_unlock();
2321 continue;
2322 }
2323
2324 /*
2325 * because this is an RCU protected lookup, we could
2326 * find a recently freed or even reallocated inode
2327 * during the lookup. We need to check under the
2328 * i_flags_lock for a valid inode here. Skip it if it
2329 * is not valid, the wrong inode or stale.
2330 */
2331 spin_lock(&ip->i_flags_lock);
2332 if (ip->i_ino != inum + i ||
2333 __xfs_iflags_test(ip, XFS_ISTALE)) {
2334 spin_unlock(&ip->i_flags_lock);
2335 rcu_read_unlock();
2336 continue;
2337 }
2338 spin_unlock(&ip->i_flags_lock);
2339
2340 /*
2341 * Don't try to lock/unlock the current inode, but we
2342 * _cannot_ skip the other inodes that we did not find
2343 * in the list attached to the buffer and are not
2344 * already marked stale. If we can't lock it, back off
2345 * and retry.
2346 */
2347 if (ip != free_ip) {
2348 if (!xfs_ilock_nowait(ip, XFS_ILOCK_EXCL)) {
2349 rcu_read_unlock();
2350 delay(1);
2351 goto retry;
2352 }
2353
2354 /*
2355 * Check the inode number again in case we're
2356 * racing with freeing in xfs_reclaim_inode().
2357 * See the comments in that function for more
2358 * information as to why the initial check is
2359 * not sufficient.
2360 */
2361 if (ip->i_ino != inum + i) {
2362 xfs_iunlock(ip, XFS_ILOCK_EXCL);
2363 rcu_read_unlock();
2364 continue;
2365 }
2366 }
2367 rcu_read_unlock();
2368
2369 xfs_iflock(ip);
2370 xfs_iflags_set(ip, XFS_ISTALE);
2371
2372 /*
2373 * we don't need to attach clean inodes or those only
2374 * with unlogged changes (which we throw away, anyway).
2375 */
2376 iip = ip->i_itemp;
2377 if (!iip || xfs_inode_clean(ip)) {
2378 ASSERT(ip != free_ip);
2379 xfs_ifunlock(ip);
2380 xfs_iunlock(ip, XFS_ILOCK_EXCL);
2381 continue;
2382 }
2383
2384 iip->ili_last_fields = iip->ili_fields;
2385 iip->ili_fields = 0;
2386 iip->ili_fsync_fields = 0;
2387 iip->ili_logged = 1;
2388 xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn,
2389 &iip->ili_item.li_lsn);
2390
2391 xfs_buf_attach_iodone(bp, xfs_istale_done,
2392 &iip->ili_item);
2393
2394 if (ip != free_ip)
2395 xfs_iunlock(ip, XFS_ILOCK_EXCL);
2396 }
2397
2398 xfs_trans_stale_inode_buf(tp, bp);
2399 xfs_trans_binval(tp, bp);
2400 }
2401
2402 xfs_perag_put(pag);
2403 return 0;
2404}
2405
2406/*
2407 * Free any local-format buffers sitting around before we reset to
2408 * extents format.
2409 */
2410static inline void
2411xfs_ifree_local_data(
2412 struct xfs_inode *ip,
2413 int whichfork)
2414{
2415 struct xfs_ifork *ifp;
2416
2417 if (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_LOCAL)
2418 return;
2419
2420 ifp = XFS_IFORK_PTR(ip, whichfork);
2421 xfs_idata_realloc(ip, -ifp->if_bytes, whichfork);
2422}
2423
2424/*
2425 * This is called to return an inode to the inode free list.
2426 * The inode should already be truncated to 0 length and have
2427 * no pages associated with it. This routine also assumes that
2428 * the inode is already a part of the transaction.
2429 *
2430 * The on-disk copy of the inode will have been added to the list
2431 * of unlinked inodes in the AGI. We need to remove the inode from
2432 * that list atomically with respect to freeing it here.
2433 */
2434int
2435xfs_ifree(
2436 xfs_trans_t *tp,
2437 xfs_inode_t *ip,
2438 struct xfs_defer_ops *dfops)
2439{
2440 int error;
2441 struct xfs_icluster xic = { 0 };
2442
2443 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
2444 ASSERT(VFS_I(ip)->i_nlink == 0);
2445 ASSERT(ip->i_d.di_nextents == 0);
2446 ASSERT(ip->i_d.di_anextents == 0);
2447 ASSERT(ip->i_d.di_size == 0 || !S_ISREG(VFS_I(ip)->i_mode));
2448 ASSERT(ip->i_d.di_nblocks == 0);
2449
2450 /*
2451 * Pull the on-disk inode from the AGI unlinked list.
2452 */
2453 error = xfs_iunlink_remove(tp, ip);
2454 if (error)
2455 return error;
2456
2457 error = xfs_difree(tp, ip->i_ino, dfops, &xic);
2458 if (error)
2459 return error;
2460
2461 xfs_ifree_local_data(ip, XFS_DATA_FORK);
2462 xfs_ifree_local_data(ip, XFS_ATTR_FORK);
2463
2464 VFS_I(ip)->i_mode = 0; /* mark incore inode as free */
2465 ip->i_d.di_flags = 0;
2466 ip->i_d.di_flags2 = 0;
2467 ip->i_d.di_dmevmask = 0;
2468 ip->i_d.di_forkoff = 0; /* mark the attr fork not in use */
2469 ip->i_d.di_format = XFS_DINODE_FMT_EXTENTS;
2470 ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;
2471
2472 /* Don't attempt to replay owner changes for a deleted inode */
2473 ip->i_itemp->ili_fields &= ~(XFS_ILOG_AOWNER|XFS_ILOG_DOWNER);
2474
2475 /*
2476 * Bump the generation count so no one will be confused
2477 * by reincarnations of this inode.
2478 */
2479 VFS_I(ip)->i_generation++;
2480 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
2481
2482 if (xic.deleted)
2483 error = xfs_ifree_cluster(ip, tp, &xic);
2484
2485 return error;
2486}
2487
2488/*
2489 * This is called to unpin an inode. The caller must have the inode locked
2490 * in at least shared mode so that the buffer cannot be subsequently pinned
2491 * once someone is waiting for it to be unpinned.
2492 */
2493static void
2494xfs_iunpin(
2495 struct xfs_inode *ip)
2496{
2497 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
2498
2499 trace_xfs_inode_unpin_nowait(ip, _RET_IP_);
2500
2501 /* Give the log a push to start the unpinning I/O */
2502 xfs_log_force_lsn(ip->i_mount, ip->i_itemp->ili_last_lsn, 0, NULL);
2503
2504}
2505
2506static void
2507__xfs_iunpin_wait(
2508 struct xfs_inode *ip)
2509{
2510 wait_queue_head_t *wq = bit_waitqueue(&ip->i_flags, __XFS_IPINNED_BIT);
2511 DEFINE_WAIT_BIT(wait, &ip->i_flags, __XFS_IPINNED_BIT);
2512
2513 xfs_iunpin(ip);
2514
2515 do {
2516 prepare_to_wait(wq, &wait.wq_entry, TASK_UNINTERRUPTIBLE);
2517 if (xfs_ipincount(ip))
2518 io_schedule();
2519 } while (xfs_ipincount(ip));
2520 finish_wait(wq, &wait.wq_entry);
2521}
2522
2523void
2524xfs_iunpin_wait(
2525 struct xfs_inode *ip)
2526{
2527 if (xfs_ipincount(ip))
2528 __xfs_iunpin_wait(ip);
2529}
2530
2531/*
2532 * Removing an inode from the namespace involves removing the directory entry
2533 * and dropping the link count on the inode. Removing the directory entry can
2534 * result in locking an AGF (directory blocks were freed) and removing a link
2535 * count can result in placing the inode on an unlinked list which results in
2536 * locking an AGI.
2537 *
2538 * The big problem here is that we have an ordering constraint on AGF and AGI
2539 * locking - inode allocation locks the AGI, then can allocate a new extent for
2540 * new inodes, locking the AGF after the AGI. Similarly, freeing the inode
2541 * removes the inode from the unlinked list, requiring that we lock the AGI
2542 * first, and then freeing the inode can result in an inode chunk being freed
2543 * and hence freeing disk space requiring that we lock an AGF.
2544 *
2545 * Hence the ordering that is imposed by other parts of the code is AGI before
2546 * AGF. This means we cannot remove the directory entry before we drop the inode
2547 * reference count and put it on the unlinked list as this results in a lock
2548 * order of AGF then AGI, and this can deadlock against inode allocation and
2549 * freeing. Therefore we must drop the link counts before we remove the
2550 * directory entry.
2551 *
2552 * This is still safe from a transactional point of view - it is not until we
2553 * get to xfs_defer_finish() that we have the possibility of multiple
2554 * transactions in this operation. Hence as long as we remove the directory
2555 * entry and drop the link count in the first transaction of the remove
2556 * operation, there are no transactional constraints on the ordering here.
2557 */
2558int
2559xfs_remove(
2560 xfs_inode_t *dp,
2561 struct xfs_name *name,
2562 xfs_inode_t *ip)
2563{
2564 xfs_mount_t *mp = dp->i_mount;
2565 xfs_trans_t *tp = NULL;
2566 int is_dir = S_ISDIR(VFS_I(ip)->i_mode);
2567 int error = 0;
2568 struct xfs_defer_ops dfops;
2569 xfs_fsblock_t first_block;
2570 uint resblks;
2571
2572 trace_xfs_remove(dp, name);
2573
2574 if (XFS_FORCED_SHUTDOWN(mp))
2575 return -EIO;
2576
2577 error = xfs_qm_dqattach(dp, 0);
2578 if (error)
2579 goto std_return;
2580
2581 error = xfs_qm_dqattach(ip, 0);
2582 if (error)
2583 goto std_return;
2584
2585 /*
2586 * We try to get the real space reservation first,
2587 * allowing for directory btree deletion(s) implying
2588 * possible bmap insert(s). If we can't get the space
2589 * reservation then we use 0 instead, and avoid the bmap
2590 * btree insert(s) in the directory code by, if the bmap
2591 * insert tries to happen, instead trimming the LAST
2592 * block from the directory.
2593 */
2594 resblks = XFS_REMOVE_SPACE_RES(mp);
2595 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_remove, resblks, 0, 0, &tp);
2596 if (error == -ENOSPC) {
2597 resblks = 0;
2598 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_remove, 0, 0, 0,
2599 &tp);
2600 }
2601 if (error) {
2602 ASSERT(error != -ENOSPC);
2603 goto std_return;
2604 }
2605
2606 xfs_lock_two_inodes(dp, XFS_ILOCK_EXCL, ip, XFS_ILOCK_EXCL);
2607
2608 xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
2609 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
2610
2611 /*
2612 * If we're removing a directory perform some additional validation.
2613 */
2614 if (is_dir) {
2615 ASSERT(VFS_I(ip)->i_nlink >= 2);
2616 if (VFS_I(ip)->i_nlink != 2) {
2617 error = -ENOTEMPTY;
2618 goto out_trans_cancel;
2619 }
2620 if (!xfs_dir_isempty(ip)) {
2621 error = -ENOTEMPTY;
2622 goto out_trans_cancel;
2623 }
2624
2625 /* Drop the link from ip's "..". */
2626 error = xfs_droplink(tp, dp);
2627 if (error)
2628 goto out_trans_cancel;
2629
2630 /* Drop the "." link from ip to self. */
2631 error = xfs_droplink(tp, ip);
2632 if (error)
2633 goto out_trans_cancel;
2634 } else {
2635 /*
2636 * When removing a non-directory we need to log the parent
2637 * inode here. For a directory this is done implicitly
2638 * by the xfs_droplink call for the ".." entry.
2639 */
2640 xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
2641 }
2642 xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2643
2644 /* Drop the link from dp to ip. */
2645 error = xfs_droplink(tp, ip);
2646 if (error)
2647 goto out_trans_cancel;
2648
2649 xfs_defer_init(&dfops, &first_block);
2650 error = xfs_dir_removename(tp, dp, name, ip->i_ino,
2651 &first_block, &dfops, resblks);
2652 if (error) {
2653 ASSERT(error != -ENOENT);
2654 goto out_bmap_cancel;
2655 }
2656
2657 /*
2658 * If this is a synchronous mount, make sure that the
2659 * remove transaction goes to disk before returning to
2660 * the user.
2661 */
2662 if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
2663 xfs_trans_set_sync(tp);
2664
2665 error = xfs_defer_finish(&tp, &dfops);
2666 if (error)
2667 goto out_bmap_cancel;
2668
2669 error = xfs_trans_commit(tp);
2670 if (error)
2671 goto std_return;
2672
2673 if (is_dir && xfs_inode_is_filestream(ip))
2674 xfs_filestream_deassociate(ip);
2675
2676 return 0;
2677
2678 out_bmap_cancel:
2679 xfs_defer_cancel(&dfops);
2680 out_trans_cancel:
2681 xfs_trans_cancel(tp);
2682 std_return:
2683 return error;
2684}
2685
2686/*
2687 * Enter all inodes for a rename transaction into a sorted array.
2688 */
2689#define __XFS_SORT_INODES 5
2690STATIC void
2691xfs_sort_for_rename(
2692 struct xfs_inode *dp1, /* in: old (source) directory inode */
2693 struct xfs_inode *dp2, /* in: new (target) directory inode */
2694 struct xfs_inode *ip1, /* in: inode of old entry */
2695 struct xfs_inode *ip2, /* in: inode of new entry */
2696 struct xfs_inode *wip, /* in: whiteout inode */
2697 struct xfs_inode **i_tab,/* out: sorted array of inodes */
2698 int *num_inodes) /* in/out: inodes in array */
2699{
2700 int i, j;
2701
2702 ASSERT(*num_inodes == __XFS_SORT_INODES);
2703 memset(i_tab, 0, *num_inodes * sizeof(struct xfs_inode *));
2704
2705 /*
2706 * i_tab contains a list of pointers to inodes. We initialize
2707 * the table here & we'll sort it. We will then use it to
2708 * order the acquisition of the inode locks.
2709 *
2710 * Note that the table may contain duplicates. e.g., dp1 == dp2.
2711 */
2712 i = 0;
2713 i_tab[i++] = dp1;
2714 i_tab[i++] = dp2;
2715 i_tab[i++] = ip1;
2716 if (ip2)
2717 i_tab[i++] = ip2;
2718 if (wip)
2719 i_tab[i++] = wip;
2720 *num_inodes = i;
2721
2722 /*
2723 * Sort the elements via bubble sort. (Remember, there are at
2724 * most 5 elements to sort, so this is adequate.)
2725 */
2726 for (i = 0; i < *num_inodes; i++) {
2727 for (j = 1; j < *num_inodes; j++) {
2728 if (i_tab[j]->i_ino < i_tab[j-1]->i_ino) {
2729 struct xfs_inode *temp = i_tab[j];
2730 i_tab[j] = i_tab[j-1];
2731 i_tab[j-1] = temp;
2732 }
2733 }
2734 }
2735}
2736
2737static int
2738xfs_finish_rename(
2739 struct xfs_trans *tp,
2740 struct xfs_defer_ops *dfops)
2741{
2742 int error;
2743
2744 /*
2745 * If this is a synchronous mount, make sure that the rename transaction
2746 * goes to disk before returning to the user.
2747 */
2748 if (tp->t_mountp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
2749 xfs_trans_set_sync(tp);
2750
2751 error = xfs_defer_finish(&tp, dfops);
2752 if (error) {
2753 xfs_defer_cancel(dfops);
2754 xfs_trans_cancel(tp);
2755 return error;
2756 }
2757
2758 return xfs_trans_commit(tp);
2759}
2760
2761/*
2762 * xfs_cross_rename()
2763 *
2764 * responsible for handling RENAME_EXCHANGE flag in renameat2() sytemcall
2765 */
2766STATIC int
2767xfs_cross_rename(
2768 struct xfs_trans *tp,
2769 struct xfs_inode *dp1,
2770 struct xfs_name *name1,
2771 struct xfs_inode *ip1,
2772 struct xfs_inode *dp2,
2773 struct xfs_name *name2,
2774 struct xfs_inode *ip2,
2775 struct xfs_defer_ops *dfops,
2776 xfs_fsblock_t *first_block,
2777 int spaceres)
2778{
2779 int error = 0;
2780 int ip1_flags = 0;
2781 int ip2_flags = 0;
2782 int dp2_flags = 0;
2783
2784 /* Swap inode number for dirent in first parent */
2785 error = xfs_dir_replace(tp, dp1, name1,
2786 ip2->i_ino,
2787 first_block, dfops, spaceres);
2788 if (error)
2789 goto out_trans_abort;
2790
2791 /* Swap inode number for dirent in second parent */
2792 error = xfs_dir_replace(tp, dp2, name2,
2793 ip1->i_ino,
2794 first_block, dfops, spaceres);
2795 if (error)
2796 goto out_trans_abort;
2797
2798 /*
2799 * If we're renaming one or more directories across different parents,
2800 * update the respective ".." entries (and link counts) to match the new
2801 * parents.
2802 */
2803 if (dp1 != dp2) {
2804 dp2_flags = XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
2805
2806 if (S_ISDIR(VFS_I(ip2)->i_mode)) {
2807 error = xfs_dir_replace(tp, ip2, &xfs_name_dotdot,
2808 dp1->i_ino, first_block,
2809 dfops, spaceres);
2810 if (error)
2811 goto out_trans_abort;
2812
2813 /* transfer ip2 ".." reference to dp1 */
2814 if (!S_ISDIR(VFS_I(ip1)->i_mode)) {
2815 error = xfs_droplink(tp, dp2);
2816 if (error)
2817 goto out_trans_abort;
2818 error = xfs_bumplink(tp, dp1);
2819 if (error)
2820 goto out_trans_abort;
2821 }
2822
2823 /*
2824 * Although ip1 isn't changed here, userspace needs
2825 * to be warned about the change, so that applications
2826 * relying on it (like backup ones), will properly
2827 * notify the change
2828 */
2829 ip1_flags |= XFS_ICHGTIME_CHG;
2830 ip2_flags |= XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
2831 }
2832
2833 if (S_ISDIR(VFS_I(ip1)->i_mode)) {
2834 error = xfs_dir_replace(tp, ip1, &xfs_name_dotdot,
2835 dp2->i_ino, first_block,
2836 dfops, spaceres);
2837 if (error)
2838 goto out_trans_abort;
2839
2840 /* transfer ip1 ".." reference to dp2 */
2841 if (!S_ISDIR(VFS_I(ip2)->i_mode)) {
2842 error = xfs_droplink(tp, dp1);
2843 if (error)
2844 goto out_trans_abort;
2845 error = xfs_bumplink(tp, dp2);
2846 if (error)
2847 goto out_trans_abort;
2848 }
2849
2850 /*
2851 * Although ip2 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_MOD | XFS_ICHGTIME_CHG;
2857 ip2_flags |= XFS_ICHGTIME_CHG;
2858 }
2859 }
2860
2861 if (ip1_flags) {
2862 xfs_trans_ichgtime(tp, ip1, ip1_flags);
2863 xfs_trans_log_inode(tp, ip1, XFS_ILOG_CORE);
2864 }
2865 if (ip2_flags) {
2866 xfs_trans_ichgtime(tp, ip2, ip2_flags);
2867 xfs_trans_log_inode(tp, ip2, XFS_ILOG_CORE);
2868 }
2869 if (dp2_flags) {
2870 xfs_trans_ichgtime(tp, dp2, dp2_flags);
2871 xfs_trans_log_inode(tp, dp2, XFS_ILOG_CORE);
2872 }
2873 xfs_trans_ichgtime(tp, dp1, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2874 xfs_trans_log_inode(tp, dp1, XFS_ILOG_CORE);
2875 return xfs_finish_rename(tp, dfops);
2876
2877out_trans_abort:
2878 xfs_defer_cancel(dfops);
2879 xfs_trans_cancel(tp);
2880 return error;
2881}
2882
2883/*
2884 * xfs_rename_alloc_whiteout()
2885 *
2886 * Return a referenced, unlinked, unlocked inode that that can be used as a
2887 * whiteout in a rename transaction. We use a tmpfile inode here so that if we
2888 * crash between allocating the inode and linking it into the rename transaction
2889 * recovery will free the inode and we won't leak it.
2890 */
2891static int
2892xfs_rename_alloc_whiteout(
2893 struct xfs_inode *dp,
2894 struct xfs_inode **wip)
2895{
2896 struct xfs_inode *tmpfile;
2897 int error;
2898
2899 error = xfs_create_tmpfile(dp, S_IFCHR | WHITEOUT_MODE, &tmpfile);
2900 if (error)
2901 return error;
2902
2903 /*
2904 * Prepare the tmpfile inode as if it were created through the VFS.
2905 * Otherwise, the link increment paths will complain about nlink 0->1.
2906 * Drop the link count as done by d_tmpfile(), complete the inode setup
2907 * and flag it as linkable.
2908 */
2909 drop_nlink(VFS_I(tmpfile));
2910 xfs_setup_iops(tmpfile);
2911 xfs_finish_inode_setup(tmpfile);
2912 VFS_I(tmpfile)->i_state |= I_LINKABLE;
2913
2914 *wip = tmpfile;
2915 return 0;
2916}
2917
2918/*
2919 * xfs_rename
2920 */
2921int
2922xfs_rename(
2923 struct xfs_inode *src_dp,
2924 struct xfs_name *src_name,
2925 struct xfs_inode *src_ip,
2926 struct xfs_inode *target_dp,
2927 struct xfs_name *target_name,
2928 struct xfs_inode *target_ip,
2929 unsigned int flags)
2930{
2931 struct xfs_mount *mp = src_dp->i_mount;
2932 struct xfs_trans *tp;
2933 struct xfs_defer_ops dfops;
2934 xfs_fsblock_t first_block;
2935 struct xfs_inode *wip = NULL; /* whiteout inode */
2936 struct xfs_inode *inodes[__XFS_SORT_INODES];
2937 int num_inodes = __XFS_SORT_INODES;
2938 bool new_parent = (src_dp != target_dp);
2939 bool src_is_directory = S_ISDIR(VFS_I(src_ip)->i_mode);
2940 int spaceres;
2941 int error;
2942
2943 trace_xfs_rename(src_dp, target_dp, src_name, target_name);
2944
2945 if ((flags & RENAME_EXCHANGE) && !target_ip)
2946 return -EINVAL;
2947
2948 /*
2949 * If we are doing a whiteout operation, allocate the whiteout inode
2950 * we will be placing at the target and ensure the type is set
2951 * appropriately.
2952 */
2953 if (flags & RENAME_WHITEOUT) {
2954 ASSERT(!(flags & (RENAME_NOREPLACE | RENAME_EXCHANGE)));
2955 error = xfs_rename_alloc_whiteout(target_dp, &wip);
2956 if (error)
2957 return error;
2958
2959 /* setup target dirent info as whiteout */
2960 src_name->type = XFS_DIR3_FT_CHRDEV;
2961 }
2962
2963 xfs_sort_for_rename(src_dp, target_dp, src_ip, target_ip, wip,
2964 inodes, &num_inodes);
2965
2966 spaceres = XFS_RENAME_SPACE_RES(mp, target_name->len);
2967 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_rename, spaceres, 0, 0, &tp);
2968 if (error == -ENOSPC) {
2969 spaceres = 0;
2970 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_rename, 0, 0, 0,
2971 &tp);
2972 }
2973 if (error)
2974 goto out_release_wip;
2975
2976 /*
2977 * Attach the dquots to the inodes
2978 */
2979 error = xfs_qm_vop_rename_dqattach(inodes);
2980 if (error)
2981 goto out_trans_cancel;
2982
2983 /*
2984 * Lock all the participating inodes. Depending upon whether
2985 * the target_name exists in the target directory, and
2986 * whether the target directory is the same as the source
2987 * directory, we can lock from 2 to 4 inodes.
2988 */
2989 xfs_lock_inodes(inodes, num_inodes, XFS_ILOCK_EXCL);
2990
2991 /*
2992 * Join all the inodes to the transaction. From this point on,
2993 * we can rely on either trans_commit or trans_cancel to unlock
2994 * them.
2995 */
2996 xfs_trans_ijoin(tp, src_dp, XFS_ILOCK_EXCL);
2997 if (new_parent)
2998 xfs_trans_ijoin(tp, target_dp, XFS_ILOCK_EXCL);
2999 xfs_trans_ijoin(tp, src_ip, XFS_ILOCK_EXCL);
3000 if (target_ip)
3001 xfs_trans_ijoin(tp, target_ip, XFS_ILOCK_EXCL);
3002 if (wip)
3003 xfs_trans_ijoin(tp, wip, XFS_ILOCK_EXCL);
3004
3005 /*
3006 * If we are using project inheritance, we only allow renames
3007 * into our tree when the project IDs are the same; else the
3008 * tree quota mechanism would be circumvented.
3009 */
3010 if (unlikely((target_dp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) &&
3011 (xfs_get_projid(target_dp) != xfs_get_projid(src_ip)))) {
3012 error = -EXDEV;
3013 goto out_trans_cancel;
3014 }
3015
3016 xfs_defer_init(&dfops, &first_block);
3017
3018 /* RENAME_EXCHANGE is unique from here on. */
3019 if (flags & RENAME_EXCHANGE)
3020 return xfs_cross_rename(tp, src_dp, src_name, src_ip,
3021 target_dp, target_name, target_ip,
3022 &dfops, &first_block, spaceres);
3023
3024 /*
3025 * Set up the target.
3026 */
3027 if (target_ip == NULL) {
3028 /*
3029 * If there's no space reservation, check the entry will
3030 * fit before actually inserting it.
3031 */
3032 if (!spaceres) {
3033 error = xfs_dir_canenter(tp, target_dp, target_name);
3034 if (error)
3035 goto out_trans_cancel;
3036 }
3037 /*
3038 * If target does not exist and the rename crosses
3039 * directories, adjust the target directory link count
3040 * to account for the ".." reference from the new entry.
3041 */
3042 error = xfs_dir_createname(tp, target_dp, target_name,
3043 src_ip->i_ino, &first_block,
3044 &dfops, spaceres);
3045 if (error)
3046 goto out_bmap_cancel;
3047
3048 xfs_trans_ichgtime(tp, target_dp,
3049 XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
3050
3051 if (new_parent && src_is_directory) {
3052 error = xfs_bumplink(tp, target_dp);
3053 if (error)
3054 goto out_bmap_cancel;
3055 }
3056 } else { /* target_ip != NULL */
3057 /*
3058 * If target exists and it's a directory, check that both
3059 * target and source are directories and that target can be
3060 * destroyed, or that neither is a directory.
3061 */
3062 if (S_ISDIR(VFS_I(target_ip)->i_mode)) {
3063 /*
3064 * Make sure target dir is empty.
3065 */
3066 if (!(xfs_dir_isempty(target_ip)) ||
3067 (VFS_I(target_ip)->i_nlink > 2)) {
3068 error = -EEXIST;
3069 goto out_trans_cancel;
3070 }
3071 }
3072
3073 /*
3074 * Link the source inode under the target name.
3075 * If the source inode is a directory and we are moving
3076 * it across directories, its ".." entry will be
3077 * inconsistent until we replace that down below.
3078 *
3079 * In case there is already an entry with the same
3080 * name at the destination directory, remove it first.
3081 */
3082 error = xfs_dir_replace(tp, target_dp, target_name,
3083 src_ip->i_ino,
3084 &first_block, &dfops, spaceres);
3085 if (error)
3086 goto out_bmap_cancel;
3087
3088 xfs_trans_ichgtime(tp, target_dp,
3089 XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
3090
3091 /*
3092 * Decrement the link count on the target since the target
3093 * dir no longer points to it.
3094 */
3095 error = xfs_droplink(tp, target_ip);
3096 if (error)
3097 goto out_bmap_cancel;
3098
3099 if (src_is_directory) {
3100 /*
3101 * Drop the link from the old "." entry.
3102 */
3103 error = xfs_droplink(tp, target_ip);
3104 if (error)
3105 goto out_bmap_cancel;
3106 }
3107 } /* target_ip != NULL */
3108
3109 /*
3110 * Remove the source.
3111 */
3112 if (new_parent && src_is_directory) {
3113 /*
3114 * Rewrite the ".." entry to point to the new
3115 * directory.
3116 */
3117 error = xfs_dir_replace(tp, src_ip, &xfs_name_dotdot,
3118 target_dp->i_ino,
3119 &first_block, &dfops, spaceres);
3120 ASSERT(error != -EEXIST);
3121 if (error)
3122 goto out_bmap_cancel;
3123 }
3124
3125 /*
3126 * We always want to hit the ctime on the source inode.
3127 *
3128 * This isn't strictly required by the standards since the source
3129 * inode isn't really being changed, but old unix file systems did
3130 * it and some incremental backup programs won't work without it.
3131 */
3132 xfs_trans_ichgtime(tp, src_ip, XFS_ICHGTIME_CHG);
3133 xfs_trans_log_inode(tp, src_ip, XFS_ILOG_CORE);
3134
3135 /*
3136 * Adjust the link count on src_dp. This is necessary when
3137 * renaming a directory, either within one parent when
3138 * the target existed, or across two parent directories.
3139 */
3140 if (src_is_directory && (new_parent || target_ip != NULL)) {
3141
3142 /*
3143 * Decrement link count on src_directory since the
3144 * entry that's moved no longer points to it.
3145 */
3146 error = xfs_droplink(tp, src_dp);
3147 if (error)
3148 goto out_bmap_cancel;
3149 }
3150
3151 /*
3152 * For whiteouts, we only need to update the source dirent with the
3153 * inode number of the whiteout inode rather than removing it
3154 * altogether.
3155 */
3156 if (wip) {
3157 error = xfs_dir_replace(tp, src_dp, src_name, wip->i_ino,
3158 &first_block, &dfops, spaceres);
3159 } else
3160 error = xfs_dir_removename(tp, src_dp, src_name, src_ip->i_ino,
3161 &first_block, &dfops, spaceres);
3162 if (error)
3163 goto out_bmap_cancel;
3164
3165 /*
3166 * For whiteouts, we need to bump the link count on the whiteout inode.
3167 * This means that failures all the way up to this point leave the inode
3168 * on the unlinked list and so cleanup is a simple matter of dropping
3169 * the remaining reference to it. If we fail here after bumping the link
3170 * count, we're shutting down the filesystem so we'll never see the
3171 * intermediate state on disk.
3172 */
3173 if (wip) {
3174 ASSERT(VFS_I(wip)->i_nlink == 0);
3175 error = xfs_bumplink(tp, wip);
3176 if (error)
3177 goto out_bmap_cancel;
3178 error = xfs_iunlink_remove(tp, wip);
3179 if (error)
3180 goto out_bmap_cancel;
3181 xfs_trans_log_inode(tp, wip, XFS_ILOG_CORE);
3182
3183 /*
3184 * Now we have a real link, clear the "I'm a tmpfile" state
3185 * flag from the inode so it doesn't accidentally get misused in
3186 * future.
3187 */
3188 VFS_I(wip)->i_state &= ~I_LINKABLE;
3189 }
3190
3191 xfs_trans_ichgtime(tp, src_dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
3192 xfs_trans_log_inode(tp, src_dp, XFS_ILOG_CORE);
3193 if (new_parent)
3194 xfs_trans_log_inode(tp, target_dp, XFS_ILOG_CORE);
3195
3196 error = xfs_finish_rename(tp, &dfops);
3197 if (wip)
3198 IRELE(wip);
3199 return error;
3200
3201out_bmap_cancel:
3202 xfs_defer_cancel(&dfops);
3203out_trans_cancel:
3204 xfs_trans_cancel(tp);
3205out_release_wip:
3206 if (wip)
3207 IRELE(wip);
3208 return error;
3209}
3210
3211STATIC int
3212xfs_iflush_cluster(
3213 struct xfs_inode *ip,
3214 struct xfs_buf *bp)
3215{
3216 struct xfs_mount *mp = ip->i_mount;
3217 struct xfs_perag *pag;
3218 unsigned long first_index, mask;
3219 unsigned long inodes_per_cluster;
3220 int cilist_size;
3221 struct xfs_inode **cilist;
3222 struct xfs_inode *cip;
3223 int nr_found;
3224 int clcount = 0;
3225 int bufwasdelwri;
3226 int i;
3227
3228 pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));
3229
3230 inodes_per_cluster = mp->m_inode_cluster_size >> mp->m_sb.sb_inodelog;
3231 cilist_size = inodes_per_cluster * sizeof(xfs_inode_t *);
3232 cilist = kmem_alloc(cilist_size, KM_MAYFAIL|KM_NOFS);
3233 if (!cilist)
3234 goto out_put;
3235
3236 mask = ~(((mp->m_inode_cluster_size >> mp->m_sb.sb_inodelog)) - 1);
3237 first_index = XFS_INO_TO_AGINO(mp, ip->i_ino) & mask;
3238 rcu_read_lock();
3239 /* really need a gang lookup range call here */
3240 nr_found = radix_tree_gang_lookup(&pag->pag_ici_root, (void**)cilist,
3241 first_index, inodes_per_cluster);
3242 if (nr_found == 0)
3243 goto out_free;
3244
3245 for (i = 0; i < nr_found; i++) {
3246 cip = cilist[i];
3247 if (cip == ip)
3248 continue;
3249
3250 /*
3251 * because this is an RCU protected lookup, we could find a
3252 * recently freed or even reallocated inode during the lookup.
3253 * We need to check under the i_flags_lock for a valid inode
3254 * here. Skip it if it is not valid or the wrong inode.
3255 */
3256 spin_lock(&cip->i_flags_lock);
3257 if (!cip->i_ino ||
3258 __xfs_iflags_test(cip, XFS_ISTALE)) {
3259 spin_unlock(&cip->i_flags_lock);
3260 continue;
3261 }
3262
3263 /*
3264 * Once we fall off the end of the cluster, no point checking
3265 * any more inodes in the list because they will also all be
3266 * outside the cluster.
3267 */
3268 if ((XFS_INO_TO_AGINO(mp, cip->i_ino) & mask) != first_index) {
3269 spin_unlock(&cip->i_flags_lock);
3270 break;
3271 }
3272 spin_unlock(&cip->i_flags_lock);
3273
3274 /*
3275 * Do an un-protected check to see if the inode is dirty and
3276 * is a candidate for flushing. These checks will be repeated
3277 * later after the appropriate locks are acquired.
3278 */
3279 if (xfs_inode_clean(cip) && xfs_ipincount(cip) == 0)
3280 continue;
3281
3282 /*
3283 * Try to get locks. If any are unavailable or it is pinned,
3284 * then this inode cannot be flushed and is skipped.
3285 */
3286
3287 if (!xfs_ilock_nowait(cip, XFS_ILOCK_SHARED))
3288 continue;
3289 if (!xfs_iflock_nowait(cip)) {
3290 xfs_iunlock(cip, XFS_ILOCK_SHARED);
3291 continue;
3292 }
3293 if (xfs_ipincount(cip)) {
3294 xfs_ifunlock(cip);
3295 xfs_iunlock(cip, XFS_ILOCK_SHARED);
3296 continue;
3297 }
3298
3299
3300 /*
3301 * Check the inode number again, just to be certain we are not
3302 * racing with freeing in xfs_reclaim_inode(). See the comments
3303 * in that function for more information as to why the initial
3304 * check is not sufficient.
3305 */
3306 if (!cip->i_ino) {
3307 xfs_ifunlock(cip);
3308 xfs_iunlock(cip, XFS_ILOCK_SHARED);
3309 continue;
3310 }
3311
3312 /*
3313 * arriving here means that this inode can be flushed. First
3314 * re-check that it's dirty before flushing.
3315 */
3316 if (!xfs_inode_clean(cip)) {
3317 int error;
3318 error = xfs_iflush_int(cip, bp);
3319 if (error) {
3320 xfs_iunlock(cip, XFS_ILOCK_SHARED);
3321 goto cluster_corrupt_out;
3322 }
3323 clcount++;
3324 } else {
3325 xfs_ifunlock(cip);
3326 }
3327 xfs_iunlock(cip, XFS_ILOCK_SHARED);
3328 }
3329
3330 if (clcount) {
3331 XFS_STATS_INC(mp, xs_icluster_flushcnt);
3332 XFS_STATS_ADD(mp, xs_icluster_flushinode, clcount);
3333 }
3334
3335out_free:
3336 rcu_read_unlock();
3337 kmem_free(cilist);
3338out_put:
3339 xfs_perag_put(pag);
3340 return 0;
3341
3342
3343cluster_corrupt_out:
3344 /*
3345 * Corruption detected in the clustering loop. Invalidate the
3346 * inode buffer and shut down the filesystem.
3347 */
3348 rcu_read_unlock();
3349 /*
3350 * Clean up the buffer. If it was delwri, just release it --
3351 * brelse can handle it with no problems. If not, shut down the
3352 * filesystem before releasing the buffer.
3353 */
3354 bufwasdelwri = (bp->b_flags & _XBF_DELWRI_Q);
3355 if (bufwasdelwri)
3356 xfs_buf_relse(bp);
3357
3358 xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
3359
3360 if (!bufwasdelwri) {
3361 /*
3362 * Just like incore_relse: if we have b_iodone functions,
3363 * mark the buffer as an error and call them. Otherwise
3364 * mark it as stale and brelse.
3365 */
3366 if (bp->b_iodone) {
3367 bp->b_flags &= ~XBF_DONE;
3368 xfs_buf_stale(bp);
3369 xfs_buf_ioerror(bp, -EIO);
3370 xfs_buf_ioend(bp);
3371 } else {
3372 xfs_buf_stale(bp);
3373 xfs_buf_relse(bp);
3374 }
3375 }
3376
3377 /*
3378 * Unlocks the flush lock
3379 */
3380 xfs_iflush_abort(cip, false);
3381 kmem_free(cilist);
3382 xfs_perag_put(pag);
3383 return -EFSCORRUPTED;
3384}
3385
3386/*
3387 * Flush dirty inode metadata into the backing buffer.
3388 *
3389 * The caller must have the inode lock and the inode flush lock held. The
3390 * inode lock will still be held upon return to the caller, and the inode
3391 * flush lock will be released after the inode has reached the disk.
3392 *
3393 * The caller must write out the buffer returned in *bpp and release it.
3394 */
3395int
3396xfs_iflush(
3397 struct xfs_inode *ip,
3398 struct xfs_buf **bpp)
3399{
3400 struct xfs_mount *mp = ip->i_mount;
3401 struct xfs_buf *bp = NULL;
3402 struct xfs_dinode *dip;
3403 int error;
3404
3405 XFS_STATS_INC(mp, xs_iflush_count);
3406
3407 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
3408 ASSERT(xfs_isiflocked(ip));
3409 ASSERT(ip->i_d.di_format != XFS_DINODE_FMT_BTREE ||
3410 ip->i_d.di_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK));
3411
3412 *bpp = NULL;
3413
3414 xfs_iunpin_wait(ip);
3415
3416 /*
3417 * For stale inodes we cannot rely on the backing buffer remaining
3418 * stale in cache for the remaining life of the stale inode and so
3419 * xfs_imap_to_bp() below may give us a buffer that no longer contains
3420 * inodes below. We have to check this after ensuring the inode is
3421 * unpinned so that it is safe to reclaim the stale inode after the
3422 * flush call.
3423 */
3424 if (xfs_iflags_test(ip, XFS_ISTALE)) {
3425 xfs_ifunlock(ip);
3426 return 0;
3427 }
3428
3429 /*
3430 * This may have been unpinned because the filesystem is shutting
3431 * down forcibly. If that's the case we must not write this inode
3432 * to disk, because the log record didn't make it to disk.
3433 *
3434 * We also have to remove the log item from the AIL in this case,
3435 * as we wait for an empty AIL as part of the unmount process.
3436 */
3437 if (XFS_FORCED_SHUTDOWN(mp)) {
3438 error = -EIO;
3439 goto abort_out;
3440 }
3441
3442 /*
3443 * Get the buffer containing the on-disk inode. We are doing a try-lock
3444 * operation here, so we may get an EAGAIN error. In that case, we
3445 * simply want to return with the inode still dirty.
3446 *
3447 * If we get any other error, we effectively have a corruption situation
3448 * and we cannot flush the inode, so we treat it the same as failing
3449 * xfs_iflush_int().
3450 */
3451 error = xfs_imap_to_bp(mp, NULL, &ip->i_imap, &dip, &bp, XBF_TRYLOCK,
3452 0);
3453 if (error == -EAGAIN) {
3454 xfs_ifunlock(ip);
3455 return error;
3456 }
3457 if (error)
3458 goto corrupt_out;
3459
3460 /*
3461 * First flush out the inode that xfs_iflush was called with.
3462 */
3463 error = xfs_iflush_int(ip, bp);
3464 if (error)
3465 goto corrupt_out;
3466
3467 /*
3468 * If the buffer is pinned then push on the log now so we won't
3469 * get stuck waiting in the write for too long.
3470 */
3471 if (xfs_buf_ispinned(bp))
3472 xfs_log_force(mp, 0);
3473
3474 /*
3475 * inode clustering:
3476 * see if other inodes can be gathered into this write
3477 */
3478 error = xfs_iflush_cluster(ip, bp);
3479 if (error)
3480 goto cluster_corrupt_out;
3481
3482 *bpp = bp;
3483 return 0;
3484
3485corrupt_out:
3486 if (bp)
3487 xfs_buf_relse(bp);
3488 xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
3489cluster_corrupt_out:
3490 error = -EFSCORRUPTED;
3491abort_out:
3492 /*
3493 * Unlocks the flush lock
3494 */
3495 xfs_iflush_abort(ip, false);
3496 return error;
3497}
3498
3499/*
3500 * If there are inline format data / attr forks attached to this inode,
3501 * make sure they're not corrupt.
3502 */
3503bool
3504xfs_inode_verify_forks(
3505 struct xfs_inode *ip)
3506{
3507 struct xfs_ifork *ifp;
3508 xfs_failaddr_t fa;
3509
3510 fa = xfs_ifork_verify_data(ip, &xfs_default_ifork_ops);
3511 if (fa) {
3512 ifp = XFS_IFORK_PTR(ip, XFS_DATA_FORK);
3513 xfs_inode_verifier_error(ip, -EFSCORRUPTED, "data fork",
3514 ifp->if_u1.if_data, ifp->if_bytes, fa);
3515 return false;
3516 }
3517
3518 fa = xfs_ifork_verify_attr(ip, &xfs_default_ifork_ops);
3519 if (fa) {
3520 ifp = XFS_IFORK_PTR(ip, XFS_ATTR_FORK);
3521 xfs_inode_verifier_error(ip, -EFSCORRUPTED, "attr fork",
3522 ifp ? ifp->if_u1.if_data : NULL,
3523 ifp ? ifp->if_bytes : 0, fa);
3524 return false;
3525 }
3526 return true;
3527}
3528
3529STATIC int
3530xfs_iflush_int(
3531 struct xfs_inode *ip,
3532 struct xfs_buf *bp)
3533{
3534 struct xfs_inode_log_item *iip = ip->i_itemp;
3535 struct xfs_dinode *dip;
3536 struct xfs_mount *mp = ip->i_mount;
3537
3538 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
3539 ASSERT(xfs_isiflocked(ip));
3540 ASSERT(ip->i_d.di_format != XFS_DINODE_FMT_BTREE ||
3541 ip->i_d.di_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK));
3542 ASSERT(iip != NULL && iip->ili_fields != 0);
3543 ASSERT(ip->i_d.di_version > 1);
3544
3545 /* set *dip = inode's place in the buffer */
3546 dip = xfs_buf_offset(bp, ip->i_imap.im_boffset);
3547
3548 if (XFS_TEST_ERROR(dip->di_magic != cpu_to_be16(XFS_DINODE_MAGIC),
3549 mp, XFS_ERRTAG_IFLUSH_1)) {
3550 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3551 "%s: Bad inode %Lu magic number 0x%x, ptr "PTR_FMT,
3552 __func__, ip->i_ino, be16_to_cpu(dip->di_magic), dip);
3553 goto corrupt_out;
3554 }
3555 if (S_ISREG(VFS_I(ip)->i_mode)) {
3556 if (XFS_TEST_ERROR(
3557 (ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS) &&
3558 (ip->i_d.di_format != XFS_DINODE_FMT_BTREE),
3559 mp, XFS_ERRTAG_IFLUSH_3)) {
3560 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3561 "%s: Bad regular inode %Lu, ptr "PTR_FMT,
3562 __func__, ip->i_ino, ip);
3563 goto corrupt_out;
3564 }
3565 } else if (S_ISDIR(VFS_I(ip)->i_mode)) {
3566 if (XFS_TEST_ERROR(
3567 (ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS) &&
3568 (ip->i_d.di_format != XFS_DINODE_FMT_BTREE) &&
3569 (ip->i_d.di_format != XFS_DINODE_FMT_LOCAL),
3570 mp, XFS_ERRTAG_IFLUSH_4)) {
3571 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3572 "%s: Bad directory inode %Lu, ptr "PTR_FMT,
3573 __func__, ip->i_ino, ip);
3574 goto corrupt_out;
3575 }
3576 }
3577 if (XFS_TEST_ERROR(ip->i_d.di_nextents + ip->i_d.di_anextents >
3578 ip->i_d.di_nblocks, mp, XFS_ERRTAG_IFLUSH_5)) {
3579 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3580 "%s: detected corrupt incore inode %Lu, "
3581 "total extents = %d, nblocks = %Ld, ptr "PTR_FMT,
3582 __func__, ip->i_ino,
3583 ip->i_d.di_nextents + ip->i_d.di_anextents,
3584 ip->i_d.di_nblocks, ip);
3585 goto corrupt_out;
3586 }
3587 if (XFS_TEST_ERROR(ip->i_d.di_forkoff > mp->m_sb.sb_inodesize,
3588 mp, XFS_ERRTAG_IFLUSH_6)) {
3589 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3590 "%s: bad inode %Lu, forkoff 0x%x, ptr "PTR_FMT,
3591 __func__, ip->i_ino, ip->i_d.di_forkoff, ip);
3592 goto corrupt_out;
3593 }
3594
3595 /*
3596 * Inode item log recovery for v2 inodes are dependent on the
3597 * di_flushiter count for correct sequencing. We bump the flush
3598 * iteration count so we can detect flushes which postdate a log record
3599 * during recovery. This is redundant as we now log every change and
3600 * hence this can't happen but we need to still do it to ensure
3601 * backwards compatibility with old kernels that predate logging all
3602 * inode changes.
3603 */
3604 if (ip->i_d.di_version < 3)
3605 ip->i_d.di_flushiter++;
3606
3607 /* Check the inline fork data before we write out. */
3608 if (!xfs_inode_verify_forks(ip))
3609 goto corrupt_out;
3610
3611 /*
3612 * Copy the dirty parts of the inode into the on-disk inode. We always
3613 * copy out the core of the inode, because if the inode is dirty at all
3614 * the core must be.
3615 */
3616 xfs_inode_to_disk(ip, dip, iip->ili_item.li_lsn);
3617
3618 /* Wrap, we never let the log put out DI_MAX_FLUSH */
3619 if (ip->i_d.di_flushiter == DI_MAX_FLUSH)
3620 ip->i_d.di_flushiter = 0;
3621
3622 xfs_iflush_fork(ip, dip, iip, XFS_DATA_FORK);
3623 if (XFS_IFORK_Q(ip))
3624 xfs_iflush_fork(ip, dip, iip, XFS_ATTR_FORK);
3625 xfs_inobp_check(mp, bp);
3626
3627 /*
3628 * We've recorded everything logged in the inode, so we'd like to clear
3629 * the ili_fields bits so we don't log and flush things unnecessarily.
3630 * However, we can't stop logging all this information until the data
3631 * we've copied into the disk buffer is written to disk. If we did we
3632 * might overwrite the copy of the inode in the log with all the data
3633 * after re-logging only part of it, and in the face of a crash we
3634 * wouldn't have all the data we need to recover.
3635 *
3636 * What we do is move the bits to the ili_last_fields field. When
3637 * logging the inode, these bits are moved back to the ili_fields field.
3638 * In the xfs_iflush_done() routine we clear ili_last_fields, since we
3639 * know that the information those bits represent is permanently on
3640 * disk. As long as the flush completes before the inode is logged
3641 * again, then both ili_fields and ili_last_fields will be cleared.
3642 *
3643 * We can play with the ili_fields bits here, because the inode lock
3644 * must be held exclusively in order to set bits there and the flush
3645 * lock protects the ili_last_fields bits. Set ili_logged so the flush
3646 * done routine can tell whether or not to look in the AIL. Also, store
3647 * the current LSN of the inode so that we can tell whether the item has
3648 * moved in the AIL from xfs_iflush_done(). In order to read the lsn we
3649 * need the AIL lock, because it is a 64 bit value that cannot be read
3650 * atomically.
3651 */
3652 iip->ili_last_fields = iip->ili_fields;
3653 iip->ili_fields = 0;
3654 iip->ili_fsync_fields = 0;
3655 iip->ili_logged = 1;
3656
3657 xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn,
3658 &iip->ili_item.li_lsn);
3659
3660 /*
3661 * Attach the function xfs_iflush_done to the inode's
3662 * buffer. This will remove the inode from the AIL
3663 * and unlock the inode's flush lock when the inode is
3664 * completely written to disk.
3665 */
3666 xfs_buf_attach_iodone(bp, xfs_iflush_done, &iip->ili_item);
3667
3668 /* generate the checksum. */
3669 xfs_dinode_calc_crc(mp, dip);
3670
3671 ASSERT(!list_empty(&bp->b_li_list));
3672 ASSERT(bp->b_iodone != NULL);
3673 return 0;
3674
3675corrupt_out:
3676 return -EFSCORRUPTED;
3677}