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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_sb.h"
15#include "xfs_mount.h"
16#include "xfs_defer.h"
17#include "xfs_inode.h"
18#include "xfs_dir2.h"
19#include "xfs_attr.h"
20#include "xfs_trans_space.h"
21#include "xfs_trans.h"
22#include "xfs_buf_item.h"
23#include "xfs_inode_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
39kmem_zone_t *xfs_inode_zone;
40
41/*
42 * Used in xfs_itruncate_extents(). This is the maximum number of extents
43 * freed from a file in a single transaction.
44 */
45#define XFS_ITRUNC_MAX_EXTENTS 2
46
47STATIC int xfs_iunlink(struct xfs_trans *, struct xfs_inode *);
48STATIC int xfs_iunlink_remove(struct xfs_trans *, struct xfs_inode *);
49
50/*
51 * helper function to extract extent size hint from inode
52 */
53xfs_extlen_t
54xfs_get_extsz_hint(
55 struct xfs_inode *ip)
56{
57 /*
58 * No point in aligning allocations if we need to COW to actually
59 * write to them.
60 */
61 if (xfs_is_always_cow_inode(ip))
62 return 0;
63 if ((ip->i_d.di_flags & XFS_DIFLAG_EXTSIZE) && ip->i_d.di_extsize)
64 return ip->i_d.di_extsize;
65 if (XFS_IS_REALTIME_INODE(ip))
66 return ip->i_mount->m_sb.sb_rextsize;
67 return 0;
68}
69
70/*
71 * Helper function to extract CoW extent size hint from inode.
72 * Between the extent size hint and the CoW extent size hint, we
73 * return the greater of the two. If the value is zero (automatic),
74 * use the default size.
75 */
76xfs_extlen_t
77xfs_get_cowextsz_hint(
78 struct xfs_inode *ip)
79{
80 xfs_extlen_t a, b;
81
82 a = 0;
83 if (ip->i_d.di_flags2 & XFS_DIFLAG2_COWEXTSIZE)
84 a = ip->i_d.di_cowextsize;
85 b = xfs_get_extsz_hint(ip);
86
87 a = max(a, b);
88 if (a == 0)
89 return XFS_DEFAULT_COWEXTSZ_HINT;
90 return a;
91}
92
93/*
94 * These two are wrapper routines around the xfs_ilock() routine used to
95 * centralize some grungy code. They are used in places that wish to lock the
96 * inode solely for reading the extents. The reason these places can't just
97 * call xfs_ilock(ip, XFS_ILOCK_SHARED) is that the inode lock also guards to
98 * bringing in of the extents from disk for a file in b-tree format. If the
99 * inode is in b-tree format, then we need to lock the inode exclusively until
100 * the extents are read in. Locking it exclusively all the time would limit
101 * our parallelism unnecessarily, though. What we do instead is check to see
102 * if the extents have been read in yet, and only lock the inode exclusively
103 * if they have not.
104 *
105 * The functions return a value which should be given to the corresponding
106 * xfs_iunlock() call.
107 */
108uint
109xfs_ilock_data_map_shared(
110 struct xfs_inode *ip)
111{
112 uint lock_mode = XFS_ILOCK_SHARED;
113
114 if (ip->i_df.if_format == XFS_DINODE_FMT_BTREE &&
115 (ip->i_df.if_flags & XFS_IFEXTENTS) == 0)
116 lock_mode = XFS_ILOCK_EXCL;
117 xfs_ilock(ip, lock_mode);
118 return lock_mode;
119}
120
121uint
122xfs_ilock_attr_map_shared(
123 struct xfs_inode *ip)
124{
125 uint lock_mode = XFS_ILOCK_SHARED;
126
127 if (ip->i_afp &&
128 ip->i_afp->if_format == XFS_DINODE_FMT_BTREE &&
129 (ip->i_afp->if_flags & XFS_IFEXTENTS) == 0)
130 lock_mode = XFS_ILOCK_EXCL;
131 xfs_ilock(ip, lock_mode);
132 return lock_mode;
133}
134
135/*
136 * In addition to i_rwsem in the VFS inode, the xfs inode contains 2
137 * multi-reader locks: i_mmap_lock and the i_lock. This routine allows
138 * various combinations of the locks to be obtained.
139 *
140 * The 3 locks should always be ordered so that the IO lock is obtained first,
141 * the mmap lock second and the ilock last in order to prevent deadlock.
142 *
143 * Basic locking order:
144 *
145 * i_rwsem -> i_mmap_lock -> page_lock -> i_ilock
146 *
147 * mmap_lock locking order:
148 *
149 * i_rwsem -> page lock -> mmap_lock
150 * mmap_lock -> i_mmap_lock -> page_lock
151 *
152 * The difference in mmap_lock locking order mean that we cannot hold the
153 * i_mmap_lock over syscall based read(2)/write(2) based IO. These IO paths can
154 * fault in pages during copy in/out (for buffered IO) or require the mmap_lock
155 * in get_user_pages() to map the user pages into the kernel address space for
156 * direct IO. Similarly the i_rwsem cannot be taken inside a page fault because
157 * page faults already hold the mmap_lock.
158 *
159 * Hence to serialise fully against both syscall and mmap based IO, we need to
160 * take both the i_rwsem and the i_mmap_lock. These locks should *only* be both
161 * taken in places where we need to invalidate the page cache in a race
162 * free manner (e.g. truncate, hole punch and other extent manipulation
163 * functions).
164 */
165void
166xfs_ilock(
167 xfs_inode_t *ip,
168 uint lock_flags)
169{
170 trace_xfs_ilock(ip, lock_flags, _RET_IP_);
171
172 /*
173 * You can't set both SHARED and EXCL for the same lock,
174 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
175 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
176 */
177 ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
178 (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
179 ASSERT((lock_flags & (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)) !=
180 (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL));
181 ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
182 (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
183 ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0);
184
185 if (lock_flags & XFS_IOLOCK_EXCL) {
186 down_write_nested(&VFS_I(ip)->i_rwsem,
187 XFS_IOLOCK_DEP(lock_flags));
188 } else if (lock_flags & XFS_IOLOCK_SHARED) {
189 down_read_nested(&VFS_I(ip)->i_rwsem,
190 XFS_IOLOCK_DEP(lock_flags));
191 }
192
193 if (lock_flags & XFS_MMAPLOCK_EXCL)
194 mrupdate_nested(&ip->i_mmaplock, XFS_MMAPLOCK_DEP(lock_flags));
195 else if (lock_flags & XFS_MMAPLOCK_SHARED)
196 mraccess_nested(&ip->i_mmaplock, XFS_MMAPLOCK_DEP(lock_flags));
197
198 if (lock_flags & XFS_ILOCK_EXCL)
199 mrupdate_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
200 else if (lock_flags & XFS_ILOCK_SHARED)
201 mraccess_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
202}
203
204/*
205 * This is just like xfs_ilock(), except that the caller
206 * is guaranteed not to sleep. It returns 1 if it gets
207 * the requested locks and 0 otherwise. If the IO lock is
208 * obtained but the inode lock cannot be, then the IO lock
209 * is dropped before returning.
210 *
211 * ip -- the inode being locked
212 * lock_flags -- this parameter indicates the inode's locks to be
213 * to be locked. See the comment for xfs_ilock() for a list
214 * of valid values.
215 */
216int
217xfs_ilock_nowait(
218 xfs_inode_t *ip,
219 uint lock_flags)
220{
221 trace_xfs_ilock_nowait(ip, lock_flags, _RET_IP_);
222
223 /*
224 * You can't set both SHARED and EXCL for the same lock,
225 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
226 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
227 */
228 ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
229 (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
230 ASSERT((lock_flags & (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)) !=
231 (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL));
232 ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
233 (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
234 ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0);
235
236 if (lock_flags & XFS_IOLOCK_EXCL) {
237 if (!down_write_trylock(&VFS_I(ip)->i_rwsem))
238 goto out;
239 } else if (lock_flags & XFS_IOLOCK_SHARED) {
240 if (!down_read_trylock(&VFS_I(ip)->i_rwsem))
241 goto out;
242 }
243
244 if (lock_flags & XFS_MMAPLOCK_EXCL) {
245 if (!mrtryupdate(&ip->i_mmaplock))
246 goto out_undo_iolock;
247 } else if (lock_flags & XFS_MMAPLOCK_SHARED) {
248 if (!mrtryaccess(&ip->i_mmaplock))
249 goto out_undo_iolock;
250 }
251
252 if (lock_flags & XFS_ILOCK_EXCL) {
253 if (!mrtryupdate(&ip->i_lock))
254 goto out_undo_mmaplock;
255 } else if (lock_flags & XFS_ILOCK_SHARED) {
256 if (!mrtryaccess(&ip->i_lock))
257 goto out_undo_mmaplock;
258 }
259 return 1;
260
261out_undo_mmaplock:
262 if (lock_flags & XFS_MMAPLOCK_EXCL)
263 mrunlock_excl(&ip->i_mmaplock);
264 else if (lock_flags & XFS_MMAPLOCK_SHARED)
265 mrunlock_shared(&ip->i_mmaplock);
266out_undo_iolock:
267 if (lock_flags & XFS_IOLOCK_EXCL)
268 up_write(&VFS_I(ip)->i_rwsem);
269 else if (lock_flags & XFS_IOLOCK_SHARED)
270 up_read(&VFS_I(ip)->i_rwsem);
271out:
272 return 0;
273}
274
275/*
276 * xfs_iunlock() is used to drop the inode locks acquired with
277 * xfs_ilock() and xfs_ilock_nowait(). The caller must pass
278 * in the flags given to xfs_ilock() or xfs_ilock_nowait() so
279 * that we know which locks to drop.
280 *
281 * ip -- the inode being unlocked
282 * lock_flags -- this parameter indicates the inode's locks to be
283 * to be unlocked. See the comment for xfs_ilock() for a list
284 * of valid values for this parameter.
285 *
286 */
287void
288xfs_iunlock(
289 xfs_inode_t *ip,
290 uint lock_flags)
291{
292 /*
293 * You can't set both SHARED and EXCL for the same lock,
294 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
295 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
296 */
297 ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
298 (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
299 ASSERT((lock_flags & (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)) !=
300 (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL));
301 ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
302 (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
303 ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0);
304 ASSERT(lock_flags != 0);
305
306 if (lock_flags & XFS_IOLOCK_EXCL)
307 up_write(&VFS_I(ip)->i_rwsem);
308 else if (lock_flags & XFS_IOLOCK_SHARED)
309 up_read(&VFS_I(ip)->i_rwsem);
310
311 if (lock_flags & XFS_MMAPLOCK_EXCL)
312 mrunlock_excl(&ip->i_mmaplock);
313 else if (lock_flags & XFS_MMAPLOCK_SHARED)
314 mrunlock_shared(&ip->i_mmaplock);
315
316 if (lock_flags & XFS_ILOCK_EXCL)
317 mrunlock_excl(&ip->i_lock);
318 else if (lock_flags & XFS_ILOCK_SHARED)
319 mrunlock_shared(&ip->i_lock);
320
321 trace_xfs_iunlock(ip, lock_flags, _RET_IP_);
322}
323
324/*
325 * give up write locks. the i/o lock cannot be held nested
326 * if it is being demoted.
327 */
328void
329xfs_ilock_demote(
330 xfs_inode_t *ip,
331 uint lock_flags)
332{
333 ASSERT(lock_flags & (XFS_IOLOCK_EXCL|XFS_MMAPLOCK_EXCL|XFS_ILOCK_EXCL));
334 ASSERT((lock_flags &
335 ~(XFS_IOLOCK_EXCL|XFS_MMAPLOCK_EXCL|XFS_ILOCK_EXCL)) == 0);
336
337 if (lock_flags & XFS_ILOCK_EXCL)
338 mrdemote(&ip->i_lock);
339 if (lock_flags & XFS_MMAPLOCK_EXCL)
340 mrdemote(&ip->i_mmaplock);
341 if (lock_flags & XFS_IOLOCK_EXCL)
342 downgrade_write(&VFS_I(ip)->i_rwsem);
343
344 trace_xfs_ilock_demote(ip, lock_flags, _RET_IP_);
345}
346
347#if defined(DEBUG) || defined(XFS_WARN)
348int
349xfs_isilocked(
350 xfs_inode_t *ip,
351 uint lock_flags)
352{
353 if (lock_flags & (XFS_ILOCK_EXCL|XFS_ILOCK_SHARED)) {
354 if (!(lock_flags & XFS_ILOCK_SHARED))
355 return !!ip->i_lock.mr_writer;
356 return rwsem_is_locked(&ip->i_lock.mr_lock);
357 }
358
359 if (lock_flags & (XFS_MMAPLOCK_EXCL|XFS_MMAPLOCK_SHARED)) {
360 if (!(lock_flags & XFS_MMAPLOCK_SHARED))
361 return !!ip->i_mmaplock.mr_writer;
362 return rwsem_is_locked(&ip->i_mmaplock.mr_lock);
363 }
364
365 if (lock_flags & (XFS_IOLOCK_EXCL|XFS_IOLOCK_SHARED)) {
366 if (!(lock_flags & XFS_IOLOCK_SHARED))
367 return !debug_locks ||
368 lockdep_is_held_type(&VFS_I(ip)->i_rwsem, 0);
369 return rwsem_is_locked(&VFS_I(ip)->i_rwsem);
370 }
371
372 ASSERT(0);
373 return 0;
374}
375#endif
376
377/*
378 * xfs_lockdep_subclass_ok() is only used in an ASSERT, so is only called when
379 * DEBUG or XFS_WARN is set. And MAX_LOCKDEP_SUBCLASSES is then only defined
380 * when CONFIG_LOCKDEP is set. Hence the complex define below to avoid build
381 * errors and warnings.
382 */
383#if (defined(DEBUG) || defined(XFS_WARN)) && defined(CONFIG_LOCKDEP)
384static bool
385xfs_lockdep_subclass_ok(
386 int subclass)
387{
388 return subclass < MAX_LOCKDEP_SUBCLASSES;
389}
390#else
391#define xfs_lockdep_subclass_ok(subclass) (true)
392#endif
393
394/*
395 * Bump the subclass so xfs_lock_inodes() acquires each lock with a different
396 * value. This can be called for any type of inode lock combination, including
397 * parent locking. Care must be taken to ensure we don't overrun the subclass
398 * storage fields in the class mask we build.
399 */
400static inline int
401xfs_lock_inumorder(int lock_mode, int subclass)
402{
403 int class = 0;
404
405 ASSERT(!(lock_mode & (XFS_ILOCK_PARENT | XFS_ILOCK_RTBITMAP |
406 XFS_ILOCK_RTSUM)));
407 ASSERT(xfs_lockdep_subclass_ok(subclass));
408
409 if (lock_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)) {
410 ASSERT(subclass <= XFS_IOLOCK_MAX_SUBCLASS);
411 class += subclass << XFS_IOLOCK_SHIFT;
412 }
413
414 if (lock_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) {
415 ASSERT(subclass <= XFS_MMAPLOCK_MAX_SUBCLASS);
416 class += subclass << XFS_MMAPLOCK_SHIFT;
417 }
418
419 if (lock_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)) {
420 ASSERT(subclass <= XFS_ILOCK_MAX_SUBCLASS);
421 class += subclass << XFS_ILOCK_SHIFT;
422 }
423
424 return (lock_mode & ~XFS_LOCK_SUBCLASS_MASK) | class;
425}
426
427/*
428 * The following routine will lock n inodes in exclusive mode. We assume the
429 * caller calls us with the inodes in i_ino order.
430 *
431 * We need to detect deadlock where an inode that we lock is in the AIL and we
432 * start waiting for another inode that is locked by a thread in a long running
433 * transaction (such as truncate). This can result in deadlock since the long
434 * running trans might need to wait for the inode we just locked in order to
435 * push the tail and free space in the log.
436 *
437 * xfs_lock_inodes() can only be used to lock one type of lock at a time -
438 * the iolock, the mmaplock or the ilock, but not more than one at a time. If we
439 * lock more than one at a time, lockdep will report false positives saying we
440 * have violated locking orders.
441 */
442static void
443xfs_lock_inodes(
444 struct xfs_inode **ips,
445 int inodes,
446 uint lock_mode)
447{
448 int attempts = 0, i, j, try_lock;
449 struct xfs_log_item *lp;
450
451 /*
452 * Currently supports between 2 and 5 inodes with exclusive locking. We
453 * support an arbitrary depth of locking here, but absolute limits on
454 * inodes depend on the type of locking and the limits placed by
455 * lockdep annotations in xfs_lock_inumorder. These are all checked by
456 * the asserts.
457 */
458 ASSERT(ips && inodes >= 2 && inodes <= 5);
459 ASSERT(lock_mode & (XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL |
460 XFS_ILOCK_EXCL));
461 ASSERT(!(lock_mode & (XFS_IOLOCK_SHARED | XFS_MMAPLOCK_SHARED |
462 XFS_ILOCK_SHARED)));
463 ASSERT(!(lock_mode & XFS_MMAPLOCK_EXCL) ||
464 inodes <= XFS_MMAPLOCK_MAX_SUBCLASS + 1);
465 ASSERT(!(lock_mode & XFS_ILOCK_EXCL) ||
466 inodes <= XFS_ILOCK_MAX_SUBCLASS + 1);
467
468 if (lock_mode & XFS_IOLOCK_EXCL) {
469 ASSERT(!(lock_mode & (XFS_MMAPLOCK_EXCL | XFS_ILOCK_EXCL)));
470 } else if (lock_mode & XFS_MMAPLOCK_EXCL)
471 ASSERT(!(lock_mode & XFS_ILOCK_EXCL));
472
473 try_lock = 0;
474 i = 0;
475again:
476 for (; i < inodes; i++) {
477 ASSERT(ips[i]);
478
479 if (i && (ips[i] == ips[i - 1])) /* Already locked */
480 continue;
481
482 /*
483 * If try_lock is not set yet, make sure all locked inodes are
484 * not in the AIL. If any are, set try_lock to be used later.
485 */
486 if (!try_lock) {
487 for (j = (i - 1); j >= 0 && !try_lock; j--) {
488 lp = &ips[j]->i_itemp->ili_item;
489 if (lp && test_bit(XFS_LI_IN_AIL, &lp->li_flags))
490 try_lock++;
491 }
492 }
493
494 /*
495 * If any of the previous locks we have locked is in the AIL,
496 * we must TRY to get the second and subsequent locks. If
497 * we can't get any, we must release all we have
498 * and try again.
499 */
500 if (!try_lock) {
501 xfs_ilock(ips[i], xfs_lock_inumorder(lock_mode, i));
502 continue;
503 }
504
505 /* try_lock means we have an inode locked that is in the AIL. */
506 ASSERT(i != 0);
507 if (xfs_ilock_nowait(ips[i], xfs_lock_inumorder(lock_mode, i)))
508 continue;
509
510 /*
511 * Unlock all previous guys and try again. xfs_iunlock will try
512 * to push the tail if the inode is in the AIL.
513 */
514 attempts++;
515 for (j = i - 1; j >= 0; j--) {
516 /*
517 * Check to see if we've already unlocked this one. Not
518 * the first one going back, and the inode ptr is the
519 * same.
520 */
521 if (j != (i - 1) && ips[j] == ips[j + 1])
522 continue;
523
524 xfs_iunlock(ips[j], lock_mode);
525 }
526
527 if ((attempts % 5) == 0) {
528 delay(1); /* Don't just spin the CPU */
529 }
530 i = 0;
531 try_lock = 0;
532 goto again;
533 }
534}
535
536/*
537 * xfs_lock_two_inodes() can only be used to lock one type of lock at a time -
538 * the mmaplock or the ilock, but not more than one type at a time. If we lock
539 * more than one at a time, lockdep will report false positives saying we have
540 * violated locking orders. The iolock must be double-locked separately since
541 * we use i_rwsem for that. We now support taking one lock EXCL and the other
542 * SHARED.
543 */
544void
545xfs_lock_two_inodes(
546 struct xfs_inode *ip0,
547 uint ip0_mode,
548 struct xfs_inode *ip1,
549 uint ip1_mode)
550{
551 struct xfs_inode *temp;
552 uint mode_temp;
553 int attempts = 0;
554 struct xfs_log_item *lp;
555
556 ASSERT(hweight32(ip0_mode) == 1);
557 ASSERT(hweight32(ip1_mode) == 1);
558 ASSERT(!(ip0_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)));
559 ASSERT(!(ip1_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)));
560 ASSERT(!(ip0_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) ||
561 !(ip0_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)));
562 ASSERT(!(ip1_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) ||
563 !(ip1_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)));
564 ASSERT(!(ip1_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) ||
565 !(ip0_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)));
566 ASSERT(!(ip0_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) ||
567 !(ip1_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)));
568
569 ASSERT(ip0->i_ino != ip1->i_ino);
570
571 if (ip0->i_ino > ip1->i_ino) {
572 temp = ip0;
573 ip0 = ip1;
574 ip1 = temp;
575 mode_temp = ip0_mode;
576 ip0_mode = ip1_mode;
577 ip1_mode = mode_temp;
578 }
579
580 again:
581 xfs_ilock(ip0, xfs_lock_inumorder(ip0_mode, 0));
582
583 /*
584 * If the first lock we have locked is in the AIL, we must TRY to get
585 * the second lock. If we can't get it, we must release the first one
586 * and try again.
587 */
588 lp = &ip0->i_itemp->ili_item;
589 if (lp && test_bit(XFS_LI_IN_AIL, &lp->li_flags)) {
590 if (!xfs_ilock_nowait(ip1, xfs_lock_inumorder(ip1_mode, 1))) {
591 xfs_iunlock(ip0, ip0_mode);
592 if ((++attempts % 5) == 0)
593 delay(1); /* Don't just spin the CPU */
594 goto again;
595 }
596 } else {
597 xfs_ilock(ip1, xfs_lock_inumorder(ip1_mode, 1));
598 }
599}
600
601void
602__xfs_iflock(
603 struct xfs_inode *ip)
604{
605 wait_queue_head_t *wq = bit_waitqueue(&ip->i_flags, __XFS_IFLOCK_BIT);
606 DEFINE_WAIT_BIT(wait, &ip->i_flags, __XFS_IFLOCK_BIT);
607
608 do {
609 prepare_to_wait_exclusive(wq, &wait.wq_entry, TASK_UNINTERRUPTIBLE);
610 if (xfs_isiflocked(ip))
611 io_schedule();
612 } while (!xfs_iflock_nowait(ip));
613
614 finish_wait(wq, &wait.wq_entry);
615}
616
617STATIC uint
618_xfs_dic2xflags(
619 uint16_t di_flags,
620 uint64_t di_flags2,
621 bool has_attr)
622{
623 uint flags = 0;
624
625 if (di_flags & XFS_DIFLAG_ANY) {
626 if (di_flags & XFS_DIFLAG_REALTIME)
627 flags |= FS_XFLAG_REALTIME;
628 if (di_flags & XFS_DIFLAG_PREALLOC)
629 flags |= FS_XFLAG_PREALLOC;
630 if (di_flags & XFS_DIFLAG_IMMUTABLE)
631 flags |= FS_XFLAG_IMMUTABLE;
632 if (di_flags & XFS_DIFLAG_APPEND)
633 flags |= FS_XFLAG_APPEND;
634 if (di_flags & XFS_DIFLAG_SYNC)
635 flags |= FS_XFLAG_SYNC;
636 if (di_flags & XFS_DIFLAG_NOATIME)
637 flags |= FS_XFLAG_NOATIME;
638 if (di_flags & XFS_DIFLAG_NODUMP)
639 flags |= FS_XFLAG_NODUMP;
640 if (di_flags & XFS_DIFLAG_RTINHERIT)
641 flags |= FS_XFLAG_RTINHERIT;
642 if (di_flags & XFS_DIFLAG_PROJINHERIT)
643 flags |= FS_XFLAG_PROJINHERIT;
644 if (di_flags & XFS_DIFLAG_NOSYMLINKS)
645 flags |= FS_XFLAG_NOSYMLINKS;
646 if (di_flags & XFS_DIFLAG_EXTSIZE)
647 flags |= FS_XFLAG_EXTSIZE;
648 if (di_flags & XFS_DIFLAG_EXTSZINHERIT)
649 flags |= FS_XFLAG_EXTSZINHERIT;
650 if (di_flags & XFS_DIFLAG_NODEFRAG)
651 flags |= FS_XFLAG_NODEFRAG;
652 if (di_flags & XFS_DIFLAG_FILESTREAM)
653 flags |= FS_XFLAG_FILESTREAM;
654 }
655
656 if (di_flags2 & XFS_DIFLAG2_ANY) {
657 if (di_flags2 & XFS_DIFLAG2_DAX)
658 flags |= FS_XFLAG_DAX;
659 if (di_flags2 & XFS_DIFLAG2_COWEXTSIZE)
660 flags |= FS_XFLAG_COWEXTSIZE;
661 }
662
663 if (has_attr)
664 flags |= FS_XFLAG_HASATTR;
665
666 return flags;
667}
668
669uint
670xfs_ip2xflags(
671 struct xfs_inode *ip)
672{
673 struct xfs_icdinode *dic = &ip->i_d;
674
675 return _xfs_dic2xflags(dic->di_flags, dic->di_flags2, XFS_IFORK_Q(ip));
676}
677
678/*
679 * Lookups up an inode from "name". If ci_name is not NULL, then a CI match
680 * is allowed, otherwise it has to be an exact match. If a CI match is found,
681 * ci_name->name will point to a the actual name (caller must free) or
682 * will be set to NULL if an exact match is found.
683 */
684int
685xfs_lookup(
686 xfs_inode_t *dp,
687 struct xfs_name *name,
688 xfs_inode_t **ipp,
689 struct xfs_name *ci_name)
690{
691 xfs_ino_t inum;
692 int error;
693
694 trace_xfs_lookup(dp, name);
695
696 if (XFS_FORCED_SHUTDOWN(dp->i_mount))
697 return -EIO;
698
699 error = xfs_dir_lookup(NULL, dp, name, &inum, ci_name);
700 if (error)
701 goto out_unlock;
702
703 error = xfs_iget(dp->i_mount, NULL, inum, 0, 0, ipp);
704 if (error)
705 goto out_free_name;
706
707 return 0;
708
709out_free_name:
710 if (ci_name)
711 kmem_free(ci_name->name);
712out_unlock:
713 *ipp = NULL;
714 return error;
715}
716
717/*
718 * Allocate an inode on disk and return a copy of its in-core version.
719 * The in-core inode is locked exclusively. Set mode, nlink, and rdev
720 * appropriately within the inode. The uid and gid for the inode are
721 * set according to the contents of the given cred structure.
722 *
723 * Use xfs_dialloc() to allocate the on-disk inode. If xfs_dialloc()
724 * has a free inode available, call xfs_iget() to obtain the in-core
725 * version of the allocated inode. Finally, fill in the inode and
726 * log its initial contents. In this case, ialloc_context would be
727 * set to NULL.
728 *
729 * If xfs_dialloc() does not have an available inode, it will replenish
730 * its supply by doing an allocation. Since we can only do one
731 * allocation within a transaction without deadlocks, we must commit
732 * the current transaction before returning the inode itself.
733 * In this case, therefore, we will set ialloc_context and return.
734 * The caller should then commit the current transaction, start a new
735 * transaction, and call xfs_ialloc() again to actually get the inode.
736 *
737 * To ensure that some other process does not grab the inode that
738 * was allocated during the first call to xfs_ialloc(), this routine
739 * also returns the [locked] bp pointing to the head of the freelist
740 * as ialloc_context. The caller should hold this buffer across
741 * the commit and pass it back into this routine on the second call.
742 *
743 * If we are allocating quota inodes, we do not have a parent inode
744 * to attach to or associate with (i.e. pip == NULL) because they
745 * are not linked into the directory structure - they are attached
746 * directly to the superblock - and so have no parent.
747 */
748static int
749xfs_ialloc(
750 xfs_trans_t *tp,
751 xfs_inode_t *pip,
752 umode_t mode,
753 xfs_nlink_t nlink,
754 dev_t rdev,
755 prid_t prid,
756 xfs_buf_t **ialloc_context,
757 xfs_inode_t **ipp)
758{
759 struct xfs_mount *mp = tp->t_mountp;
760 xfs_ino_t ino;
761 xfs_inode_t *ip;
762 uint flags;
763 int error;
764 struct timespec64 tv;
765 struct inode *inode;
766
767 /*
768 * Call the space management code to pick
769 * the on-disk inode to be allocated.
770 */
771 error = xfs_dialloc(tp, pip ? pip->i_ino : 0, mode,
772 ialloc_context, &ino);
773 if (error)
774 return error;
775 if (*ialloc_context || ino == NULLFSINO) {
776 *ipp = NULL;
777 return 0;
778 }
779 ASSERT(*ialloc_context == NULL);
780
781 /*
782 * Protect against obviously corrupt allocation btree records. Later
783 * xfs_iget checks will catch re-allocation of other active in-memory
784 * and on-disk inodes. If we don't catch reallocating the parent inode
785 * here we will deadlock in xfs_iget() so we have to do these checks
786 * first.
787 */
788 if ((pip && ino == pip->i_ino) || !xfs_verify_dir_ino(mp, ino)) {
789 xfs_alert(mp, "Allocated a known in-use inode 0x%llx!", ino);
790 return -EFSCORRUPTED;
791 }
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 inode->i_mode = mode;
805 set_nlink(inode, nlink);
806 inode->i_uid = current_fsuid();
807 inode->i_rdev = rdev;
808 ip->i_d.di_projid = prid;
809
810 if (pip && XFS_INHERIT_GID(pip)) {
811 inode->i_gid = VFS_I(pip)->i_gid;
812 if ((VFS_I(pip)->i_mode & S_ISGID) && S_ISDIR(mode))
813 inode->i_mode |= S_ISGID;
814 } else {
815 inode->i_gid = current_fsgid();
816 }
817
818 /*
819 * If the group ID of the new file does not match the effective group
820 * ID or one of the supplementary group IDs, the S_ISGID bit is cleared
821 * (and only if the irix_sgid_inherit compatibility variable is set).
822 */
823 if (irix_sgid_inherit &&
824 (inode->i_mode & S_ISGID) && !in_group_p(inode->i_gid))
825 inode->i_mode &= ~S_ISGID;
826
827 ip->i_d.di_size = 0;
828 ip->i_df.if_nextents = 0;
829 ASSERT(ip->i_d.di_nblocks == 0);
830
831 tv = current_time(inode);
832 inode->i_mtime = tv;
833 inode->i_atime = tv;
834 inode->i_ctime = tv;
835
836 ip->i_d.di_extsize = 0;
837 ip->i_d.di_dmevmask = 0;
838 ip->i_d.di_dmstate = 0;
839 ip->i_d.di_flags = 0;
840
841 if (xfs_sb_version_has_v3inode(&mp->m_sb)) {
842 inode_set_iversion(inode, 1);
843 ip->i_d.di_flags2 = 0;
844 ip->i_d.di_cowextsize = 0;
845 ip->i_d.di_crtime = tv;
846 }
847
848 flags = XFS_ILOG_CORE;
849 switch (mode & S_IFMT) {
850 case S_IFIFO:
851 case S_IFCHR:
852 case S_IFBLK:
853 case S_IFSOCK:
854 ip->i_df.if_format = XFS_DINODE_FMT_DEV;
855 ip->i_df.if_flags = 0;
856 flags |= XFS_ILOG_DEV;
857 break;
858 case S_IFREG:
859 case S_IFDIR:
860 if (pip && (pip->i_d.di_flags & XFS_DIFLAG_ANY)) {
861 uint di_flags = 0;
862
863 if (S_ISDIR(mode)) {
864 if (pip->i_d.di_flags & XFS_DIFLAG_RTINHERIT)
865 di_flags |= XFS_DIFLAG_RTINHERIT;
866 if (pip->i_d.di_flags & XFS_DIFLAG_EXTSZINHERIT) {
867 di_flags |= XFS_DIFLAG_EXTSZINHERIT;
868 ip->i_d.di_extsize = pip->i_d.di_extsize;
869 }
870 if (pip->i_d.di_flags & XFS_DIFLAG_PROJINHERIT)
871 di_flags |= XFS_DIFLAG_PROJINHERIT;
872 } else if (S_ISREG(mode)) {
873 if (pip->i_d.di_flags & XFS_DIFLAG_RTINHERIT)
874 di_flags |= XFS_DIFLAG_REALTIME;
875 if (pip->i_d.di_flags & XFS_DIFLAG_EXTSZINHERIT) {
876 di_flags |= XFS_DIFLAG_EXTSIZE;
877 ip->i_d.di_extsize = pip->i_d.di_extsize;
878 }
879 }
880 if ((pip->i_d.di_flags & XFS_DIFLAG_NOATIME) &&
881 xfs_inherit_noatime)
882 di_flags |= XFS_DIFLAG_NOATIME;
883 if ((pip->i_d.di_flags & XFS_DIFLAG_NODUMP) &&
884 xfs_inherit_nodump)
885 di_flags |= XFS_DIFLAG_NODUMP;
886 if ((pip->i_d.di_flags & XFS_DIFLAG_SYNC) &&
887 xfs_inherit_sync)
888 di_flags |= XFS_DIFLAG_SYNC;
889 if ((pip->i_d.di_flags & XFS_DIFLAG_NOSYMLINKS) &&
890 xfs_inherit_nosymlinks)
891 di_flags |= XFS_DIFLAG_NOSYMLINKS;
892 if ((pip->i_d.di_flags & XFS_DIFLAG_NODEFRAG) &&
893 xfs_inherit_nodefrag)
894 di_flags |= XFS_DIFLAG_NODEFRAG;
895 if (pip->i_d.di_flags & XFS_DIFLAG_FILESTREAM)
896 di_flags |= XFS_DIFLAG_FILESTREAM;
897
898 ip->i_d.di_flags |= di_flags;
899 }
900 if (pip && (pip->i_d.di_flags2 & XFS_DIFLAG2_ANY)) {
901 if (pip->i_d.di_flags2 & XFS_DIFLAG2_COWEXTSIZE) {
902 ip->i_d.di_flags2 |= XFS_DIFLAG2_COWEXTSIZE;
903 ip->i_d.di_cowextsize = pip->i_d.di_cowextsize;
904 }
905 if (pip->i_d.di_flags2 & XFS_DIFLAG2_DAX)
906 ip->i_d.di_flags2 |= XFS_DIFLAG2_DAX;
907 }
908 /* FALLTHROUGH */
909 case S_IFLNK:
910 ip->i_df.if_format = XFS_DINODE_FMT_EXTENTS;
911 ip->i_df.if_flags = XFS_IFEXTENTS;
912 ip->i_df.if_bytes = 0;
913 ip->i_df.if_u1.if_root = NULL;
914 break;
915 default:
916 ASSERT(0);
917 }
918
919 /*
920 * Log the new values stuffed into the inode.
921 */
922 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
923 xfs_trans_log_inode(tp, ip, flags);
924
925 /* now that we have an i_mode we can setup the inode structure */
926 xfs_setup_inode(ip);
927
928 *ipp = ip;
929 return 0;
930}
931
932/*
933 * Allocates a new inode from disk and return a pointer to the
934 * incore copy. This routine will internally commit the current
935 * transaction and allocate a new one if the Space Manager needed
936 * to do an allocation to replenish the inode free-list.
937 *
938 * This routine is designed to be called from xfs_create and
939 * xfs_create_dir.
940 *
941 */
942int
943xfs_dir_ialloc(
944 xfs_trans_t **tpp, /* input: current transaction;
945 output: may be a new transaction. */
946 xfs_inode_t *dp, /* directory within whose allocate
947 the inode. */
948 umode_t mode,
949 xfs_nlink_t nlink,
950 dev_t rdev,
951 prid_t prid, /* project id */
952 xfs_inode_t **ipp) /* pointer to inode; it will be
953 locked. */
954{
955 xfs_trans_t *tp;
956 xfs_inode_t *ip;
957 xfs_buf_t *ialloc_context = NULL;
958 int code;
959 void *dqinfo;
960 uint tflags;
961
962 tp = *tpp;
963 ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
964
965 /*
966 * xfs_ialloc will return a pointer to an incore inode if
967 * the Space Manager has an available inode on the free
968 * list. Otherwise, it will do an allocation and replenish
969 * the freelist. Since we can only do one allocation per
970 * transaction without deadlocks, we will need to commit the
971 * current transaction and start a new one. We will then
972 * need to call xfs_ialloc again to get the inode.
973 *
974 * If xfs_ialloc did an allocation to replenish the freelist,
975 * it returns the bp containing the head of the freelist as
976 * ialloc_context. We will hold a lock on it across the
977 * transaction commit so that no other process can steal
978 * the inode(s) that we've just allocated.
979 */
980 code = xfs_ialloc(tp, dp, mode, nlink, rdev, prid, &ialloc_context,
981 &ip);
982
983 /*
984 * Return an error if we were unable to allocate a new inode.
985 * This should only happen if we run out of space on disk or
986 * encounter a disk error.
987 */
988 if (code) {
989 *ipp = NULL;
990 return code;
991 }
992 if (!ialloc_context && !ip) {
993 *ipp = NULL;
994 return -ENOSPC;
995 }
996
997 /*
998 * If the AGI buffer is non-NULL, then we were unable to get an
999 * inode in one operation. We need to commit the current
1000 * transaction and call xfs_ialloc() again. It is guaranteed
1001 * to succeed the second time.
1002 */
1003 if (ialloc_context) {
1004 /*
1005 * Normally, xfs_trans_commit releases all the locks.
1006 * We call bhold to hang on to the ialloc_context across
1007 * the commit. Holding this buffer prevents any other
1008 * processes from doing any allocations in this
1009 * allocation group.
1010 */
1011 xfs_trans_bhold(tp, ialloc_context);
1012
1013 /*
1014 * We want the quota changes to be associated with the next
1015 * transaction, NOT this one. So, detach the dqinfo from this
1016 * and attach it to the next transaction.
1017 */
1018 dqinfo = NULL;
1019 tflags = 0;
1020 if (tp->t_dqinfo) {
1021 dqinfo = (void *)tp->t_dqinfo;
1022 tp->t_dqinfo = NULL;
1023 tflags = tp->t_flags & XFS_TRANS_DQ_DIRTY;
1024 tp->t_flags &= ~(XFS_TRANS_DQ_DIRTY);
1025 }
1026
1027 code = xfs_trans_roll(&tp);
1028
1029 /*
1030 * Re-attach the quota info that we detached from prev trx.
1031 */
1032 if (dqinfo) {
1033 tp->t_dqinfo = dqinfo;
1034 tp->t_flags |= tflags;
1035 }
1036
1037 if (code) {
1038 xfs_buf_relse(ialloc_context);
1039 *tpp = tp;
1040 *ipp = NULL;
1041 return code;
1042 }
1043 xfs_trans_bjoin(tp, ialloc_context);
1044
1045 /*
1046 * Call ialloc again. Since we've locked out all
1047 * other allocations in this allocation group,
1048 * this call should always succeed.
1049 */
1050 code = xfs_ialloc(tp, dp, mode, nlink, rdev, prid,
1051 &ialloc_context, &ip);
1052
1053 /*
1054 * If we get an error at this point, return to the caller
1055 * so that the current transaction can be aborted.
1056 */
1057 if (code) {
1058 *tpp = tp;
1059 *ipp = NULL;
1060 return code;
1061 }
1062 ASSERT(!ialloc_context && ip);
1063
1064 }
1065
1066 *ipp = ip;
1067 *tpp = tp;
1068
1069 return 0;
1070}
1071
1072/*
1073 * Decrement the link count on an inode & log the change. If this causes the
1074 * link count to go to zero, move the inode to AGI unlinked list so that it can
1075 * be freed when the last active reference goes away via xfs_inactive().
1076 */
1077static int /* error */
1078xfs_droplink(
1079 xfs_trans_t *tp,
1080 xfs_inode_t *ip)
1081{
1082 xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
1083
1084 drop_nlink(VFS_I(ip));
1085 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1086
1087 if (VFS_I(ip)->i_nlink)
1088 return 0;
1089
1090 return xfs_iunlink(tp, ip);
1091}
1092
1093/*
1094 * Increment the link count on an inode & log the change.
1095 */
1096static void
1097xfs_bumplink(
1098 xfs_trans_t *tp,
1099 xfs_inode_t *ip)
1100{
1101 xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
1102
1103 inc_nlink(VFS_I(ip));
1104 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1105}
1106
1107int
1108xfs_create(
1109 xfs_inode_t *dp,
1110 struct xfs_name *name,
1111 umode_t mode,
1112 dev_t rdev,
1113 xfs_inode_t **ipp)
1114{
1115 int is_dir = S_ISDIR(mode);
1116 struct xfs_mount *mp = dp->i_mount;
1117 struct xfs_inode *ip = NULL;
1118 struct xfs_trans *tp = NULL;
1119 int error;
1120 bool unlock_dp_on_error = false;
1121 prid_t prid;
1122 struct xfs_dquot *udqp = NULL;
1123 struct xfs_dquot *gdqp = NULL;
1124 struct xfs_dquot *pdqp = NULL;
1125 struct xfs_trans_res *tres;
1126 uint resblks;
1127
1128 trace_xfs_create(dp, name);
1129
1130 if (XFS_FORCED_SHUTDOWN(mp))
1131 return -EIO;
1132
1133 prid = xfs_get_initial_prid(dp);
1134
1135 /*
1136 * Make sure that we have allocated dquot(s) on disk.
1137 */
1138 error = xfs_qm_vop_dqalloc(dp, current_fsuid(), current_fsgid(), prid,
1139 XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
1140 &udqp, &gdqp, &pdqp);
1141 if (error)
1142 return error;
1143
1144 if (is_dir) {
1145 resblks = XFS_MKDIR_SPACE_RES(mp, name->len);
1146 tres = &M_RES(mp)->tr_mkdir;
1147 } else {
1148 resblks = XFS_CREATE_SPACE_RES(mp, name->len);
1149 tres = &M_RES(mp)->tr_create;
1150 }
1151
1152 /*
1153 * Initially assume that the file does not exist and
1154 * reserve the resources for that case. If that is not
1155 * the case we'll drop the one we have and get a more
1156 * appropriate transaction later.
1157 */
1158 error = xfs_trans_alloc(mp, tres, resblks, 0, 0, &tp);
1159 if (error == -ENOSPC) {
1160 /* flush outstanding delalloc blocks and retry */
1161 xfs_flush_inodes(mp);
1162 error = xfs_trans_alloc(mp, tres, resblks, 0, 0, &tp);
1163 }
1164 if (error)
1165 goto out_release_inode;
1166
1167 xfs_ilock(dp, XFS_ILOCK_EXCL | XFS_ILOCK_PARENT);
1168 unlock_dp_on_error = true;
1169
1170 /*
1171 * Reserve disk quota and the inode.
1172 */
1173 error = xfs_trans_reserve_quota(tp, mp, udqp, gdqp,
1174 pdqp, resblks, 1, 0);
1175 if (error)
1176 goto out_trans_cancel;
1177
1178 /*
1179 * A newly created regular or special file just has one directory
1180 * entry pointing to them, but a directory also the "." entry
1181 * pointing to itself.
1182 */
1183 error = xfs_dir_ialloc(&tp, dp, mode, is_dir ? 2 : 1, rdev, prid, &ip);
1184 if (error)
1185 goto out_trans_cancel;
1186
1187 /*
1188 * Now we join the directory inode to the transaction. We do not do it
1189 * earlier because xfs_dir_ialloc might commit the previous transaction
1190 * (and release all the locks). An error from here on will result in
1191 * the transaction cancel unlocking dp so don't do it explicitly in the
1192 * error path.
1193 */
1194 xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
1195 unlock_dp_on_error = false;
1196
1197 error = xfs_dir_createname(tp, dp, name, ip->i_ino,
1198 resblks - XFS_IALLOC_SPACE_RES(mp));
1199 if (error) {
1200 ASSERT(error != -ENOSPC);
1201 goto out_trans_cancel;
1202 }
1203 xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1204 xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
1205
1206 if (is_dir) {
1207 error = xfs_dir_init(tp, ip, dp);
1208 if (error)
1209 goto out_trans_cancel;
1210
1211 xfs_bumplink(tp, dp);
1212 }
1213
1214 /*
1215 * If this is a synchronous mount, make sure that the
1216 * create transaction goes to disk before returning to
1217 * the user.
1218 */
1219 if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
1220 xfs_trans_set_sync(tp);
1221
1222 /*
1223 * Attach the dquot(s) to the inodes and modify them incore.
1224 * These ids of the inode couldn't have changed since the new
1225 * inode has been locked ever since it was created.
1226 */
1227 xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp, pdqp);
1228
1229 error = xfs_trans_commit(tp);
1230 if (error)
1231 goto out_release_inode;
1232
1233 xfs_qm_dqrele(udqp);
1234 xfs_qm_dqrele(gdqp);
1235 xfs_qm_dqrele(pdqp);
1236
1237 *ipp = ip;
1238 return 0;
1239
1240 out_trans_cancel:
1241 xfs_trans_cancel(tp);
1242 out_release_inode:
1243 /*
1244 * Wait until after the current transaction is aborted to finish the
1245 * setup of the inode and release the inode. This prevents recursive
1246 * transactions and deadlocks from xfs_inactive.
1247 */
1248 if (ip) {
1249 xfs_finish_inode_setup(ip);
1250 xfs_irele(ip);
1251 }
1252
1253 xfs_qm_dqrele(udqp);
1254 xfs_qm_dqrele(gdqp);
1255 xfs_qm_dqrele(pdqp);
1256
1257 if (unlock_dp_on_error)
1258 xfs_iunlock(dp, XFS_ILOCK_EXCL);
1259 return error;
1260}
1261
1262int
1263xfs_create_tmpfile(
1264 struct xfs_inode *dp,
1265 umode_t mode,
1266 struct xfs_inode **ipp)
1267{
1268 struct xfs_mount *mp = dp->i_mount;
1269 struct xfs_inode *ip = NULL;
1270 struct xfs_trans *tp = NULL;
1271 int error;
1272 prid_t prid;
1273 struct xfs_dquot *udqp = NULL;
1274 struct xfs_dquot *gdqp = NULL;
1275 struct xfs_dquot *pdqp = NULL;
1276 struct xfs_trans_res *tres;
1277 uint resblks;
1278
1279 if (XFS_FORCED_SHUTDOWN(mp))
1280 return -EIO;
1281
1282 prid = xfs_get_initial_prid(dp);
1283
1284 /*
1285 * Make sure that we have allocated dquot(s) on disk.
1286 */
1287 error = xfs_qm_vop_dqalloc(dp, current_fsuid(), current_fsgid(), prid,
1288 XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
1289 &udqp, &gdqp, &pdqp);
1290 if (error)
1291 return error;
1292
1293 resblks = XFS_IALLOC_SPACE_RES(mp);
1294 tres = &M_RES(mp)->tr_create_tmpfile;
1295
1296 error = xfs_trans_alloc(mp, tres, resblks, 0, 0, &tp);
1297 if (error)
1298 goto out_release_inode;
1299
1300 error = xfs_trans_reserve_quota(tp, mp, udqp, gdqp,
1301 pdqp, resblks, 1, 0);
1302 if (error)
1303 goto out_trans_cancel;
1304
1305 error = xfs_dir_ialloc(&tp, dp, mode, 0, 0, prid, &ip);
1306 if (error)
1307 goto out_trans_cancel;
1308
1309 if (mp->m_flags & XFS_MOUNT_WSYNC)
1310 xfs_trans_set_sync(tp);
1311
1312 /*
1313 * Attach the dquot(s) to the inodes and modify them incore.
1314 * These ids of the inode couldn't have changed since the new
1315 * inode has been locked ever since it was created.
1316 */
1317 xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp, pdqp);
1318
1319 error = xfs_iunlink(tp, ip);
1320 if (error)
1321 goto out_trans_cancel;
1322
1323 error = xfs_trans_commit(tp);
1324 if (error)
1325 goto out_release_inode;
1326
1327 xfs_qm_dqrele(udqp);
1328 xfs_qm_dqrele(gdqp);
1329 xfs_qm_dqrele(pdqp);
1330
1331 *ipp = ip;
1332 return 0;
1333
1334 out_trans_cancel:
1335 xfs_trans_cancel(tp);
1336 out_release_inode:
1337 /*
1338 * Wait until after the current transaction is aborted to finish the
1339 * setup of the inode and release the inode. This prevents recursive
1340 * transactions and deadlocks from xfs_inactive.
1341 */
1342 if (ip) {
1343 xfs_finish_inode_setup(ip);
1344 xfs_irele(ip);
1345 }
1346
1347 xfs_qm_dqrele(udqp);
1348 xfs_qm_dqrele(gdqp);
1349 xfs_qm_dqrele(pdqp);
1350
1351 return error;
1352}
1353
1354int
1355xfs_link(
1356 xfs_inode_t *tdp,
1357 xfs_inode_t *sip,
1358 struct xfs_name *target_name)
1359{
1360 xfs_mount_t *mp = tdp->i_mount;
1361 xfs_trans_t *tp;
1362 int error;
1363 int resblks;
1364
1365 trace_xfs_link(tdp, target_name);
1366
1367 ASSERT(!S_ISDIR(VFS_I(sip)->i_mode));
1368
1369 if (XFS_FORCED_SHUTDOWN(mp))
1370 return -EIO;
1371
1372 error = xfs_qm_dqattach(sip);
1373 if (error)
1374 goto std_return;
1375
1376 error = xfs_qm_dqattach(tdp);
1377 if (error)
1378 goto std_return;
1379
1380 resblks = XFS_LINK_SPACE_RES(mp, target_name->len);
1381 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_link, resblks, 0, 0, &tp);
1382 if (error == -ENOSPC) {
1383 resblks = 0;
1384 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_link, 0, 0, 0, &tp);
1385 }
1386 if (error)
1387 goto std_return;
1388
1389 xfs_lock_two_inodes(sip, XFS_ILOCK_EXCL, tdp, XFS_ILOCK_EXCL);
1390
1391 xfs_trans_ijoin(tp, sip, XFS_ILOCK_EXCL);
1392 xfs_trans_ijoin(tp, tdp, XFS_ILOCK_EXCL);
1393
1394 /*
1395 * If we are using project inheritance, we only allow hard link
1396 * creation in our tree when the project IDs are the same; else
1397 * the tree quota mechanism could be circumvented.
1398 */
1399 if (unlikely((tdp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) &&
1400 tdp->i_d.di_projid != sip->i_d.di_projid)) {
1401 error = -EXDEV;
1402 goto error_return;
1403 }
1404
1405 if (!resblks) {
1406 error = xfs_dir_canenter(tp, tdp, target_name);
1407 if (error)
1408 goto error_return;
1409 }
1410
1411 /*
1412 * Handle initial link state of O_TMPFILE inode
1413 */
1414 if (VFS_I(sip)->i_nlink == 0) {
1415 error = xfs_iunlink_remove(tp, sip);
1416 if (error)
1417 goto error_return;
1418 }
1419
1420 error = xfs_dir_createname(tp, tdp, target_name, sip->i_ino,
1421 resblks);
1422 if (error)
1423 goto error_return;
1424 xfs_trans_ichgtime(tp, tdp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1425 xfs_trans_log_inode(tp, tdp, XFS_ILOG_CORE);
1426
1427 xfs_bumplink(tp, sip);
1428
1429 /*
1430 * If this is a synchronous mount, make sure that the
1431 * link transaction goes to disk before returning to
1432 * the user.
1433 */
1434 if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
1435 xfs_trans_set_sync(tp);
1436
1437 return xfs_trans_commit(tp);
1438
1439 error_return:
1440 xfs_trans_cancel(tp);
1441 std_return:
1442 return error;
1443}
1444
1445/* Clear the reflink flag and the cowblocks tag if possible. */
1446static void
1447xfs_itruncate_clear_reflink_flags(
1448 struct xfs_inode *ip)
1449{
1450 struct xfs_ifork *dfork;
1451 struct xfs_ifork *cfork;
1452
1453 if (!xfs_is_reflink_inode(ip))
1454 return;
1455 dfork = XFS_IFORK_PTR(ip, XFS_DATA_FORK);
1456 cfork = XFS_IFORK_PTR(ip, XFS_COW_FORK);
1457 if (dfork->if_bytes == 0 && cfork->if_bytes == 0)
1458 ip->i_d.di_flags2 &= ~XFS_DIFLAG2_REFLINK;
1459 if (cfork->if_bytes == 0)
1460 xfs_inode_clear_cowblocks_tag(ip);
1461}
1462
1463/*
1464 * Free up the underlying blocks past new_size. The new size must be smaller
1465 * than the current size. This routine can be used both for the attribute and
1466 * data fork, and does not modify the inode size, which is left to the caller.
1467 *
1468 * The transaction passed to this routine must have made a permanent log
1469 * reservation of at least XFS_ITRUNCATE_LOG_RES. This routine may commit the
1470 * given transaction and start new ones, so make sure everything involved in
1471 * the transaction is tidy before calling here. Some transaction will be
1472 * returned to the caller to be committed. The incoming transaction must
1473 * already include the inode, and both inode locks must be held exclusively.
1474 * The inode must also be "held" within the transaction. On return the inode
1475 * will be "held" within the returned transaction. This routine does NOT
1476 * require any disk space to be reserved for it within the transaction.
1477 *
1478 * If we get an error, we must return with the inode locked and linked into the
1479 * current transaction. This keeps things simple for the higher level code,
1480 * because it always knows that the inode is locked and held in the transaction
1481 * that returns to it whether errors occur or not. We don't mark the inode
1482 * dirty on error so that transactions can be easily aborted if possible.
1483 */
1484int
1485xfs_itruncate_extents_flags(
1486 struct xfs_trans **tpp,
1487 struct xfs_inode *ip,
1488 int whichfork,
1489 xfs_fsize_t new_size,
1490 int flags)
1491{
1492 struct xfs_mount *mp = ip->i_mount;
1493 struct xfs_trans *tp = *tpp;
1494 xfs_fileoff_t first_unmap_block;
1495 xfs_filblks_t unmap_len;
1496 int error = 0;
1497
1498 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
1499 ASSERT(!atomic_read(&VFS_I(ip)->i_count) ||
1500 xfs_isilocked(ip, XFS_IOLOCK_EXCL));
1501 ASSERT(new_size <= XFS_ISIZE(ip));
1502 ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
1503 ASSERT(ip->i_itemp != NULL);
1504 ASSERT(ip->i_itemp->ili_lock_flags == 0);
1505 ASSERT(!XFS_NOT_DQATTACHED(mp, ip));
1506
1507 trace_xfs_itruncate_extents_start(ip, new_size);
1508
1509 flags |= xfs_bmapi_aflag(whichfork);
1510
1511 /*
1512 * Since it is possible for space to become allocated beyond
1513 * the end of the file (in a crash where the space is allocated
1514 * but the inode size is not yet updated), simply remove any
1515 * blocks which show up between the new EOF and the maximum
1516 * possible file size.
1517 *
1518 * We have to free all the blocks to the bmbt maximum offset, even if
1519 * the page cache can't scale that far.
1520 */
1521 first_unmap_block = XFS_B_TO_FSB(mp, (xfs_ufsize_t)new_size);
1522 if (first_unmap_block >= XFS_MAX_FILEOFF) {
1523 WARN_ON_ONCE(first_unmap_block > XFS_MAX_FILEOFF);
1524 return 0;
1525 }
1526
1527 unmap_len = XFS_MAX_FILEOFF - first_unmap_block + 1;
1528 while (unmap_len > 0) {
1529 ASSERT(tp->t_firstblock == NULLFSBLOCK);
1530 error = __xfs_bunmapi(tp, ip, first_unmap_block, &unmap_len,
1531 flags, XFS_ITRUNC_MAX_EXTENTS);
1532 if (error)
1533 goto out;
1534
1535 /*
1536 * Duplicate the transaction that has the permanent
1537 * reservation and commit the old transaction.
1538 */
1539 error = xfs_defer_finish(&tp);
1540 if (error)
1541 goto out;
1542
1543 error = xfs_trans_roll_inode(&tp, ip);
1544 if (error)
1545 goto out;
1546 }
1547
1548 if (whichfork == XFS_DATA_FORK) {
1549 /* Remove all pending CoW reservations. */
1550 error = xfs_reflink_cancel_cow_blocks(ip, &tp,
1551 first_unmap_block, XFS_MAX_FILEOFF, true);
1552 if (error)
1553 goto out;
1554
1555 xfs_itruncate_clear_reflink_flags(ip);
1556 }
1557
1558 /*
1559 * Always re-log the inode so that our permanent transaction can keep
1560 * on rolling it forward in the log.
1561 */
1562 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1563
1564 trace_xfs_itruncate_extents_end(ip, new_size);
1565
1566out:
1567 *tpp = tp;
1568 return error;
1569}
1570
1571int
1572xfs_release(
1573 xfs_inode_t *ip)
1574{
1575 xfs_mount_t *mp = ip->i_mount;
1576 int error;
1577
1578 if (!S_ISREG(VFS_I(ip)->i_mode) || (VFS_I(ip)->i_mode == 0))
1579 return 0;
1580
1581 /* If this is a read-only mount, don't do this (would generate I/O) */
1582 if (mp->m_flags & XFS_MOUNT_RDONLY)
1583 return 0;
1584
1585 if (!XFS_FORCED_SHUTDOWN(mp)) {
1586 int truncated;
1587
1588 /*
1589 * If we previously truncated this file and removed old data
1590 * in the process, we want to initiate "early" writeout on
1591 * the last close. This is an attempt to combat the notorious
1592 * NULL files problem which is particularly noticeable from a
1593 * truncate down, buffered (re-)write (delalloc), followed by
1594 * a crash. What we are effectively doing here is
1595 * significantly reducing the time window where we'd otherwise
1596 * be exposed to that problem.
1597 */
1598 truncated = xfs_iflags_test_and_clear(ip, XFS_ITRUNCATED);
1599 if (truncated) {
1600 xfs_iflags_clear(ip, XFS_IDIRTY_RELEASE);
1601 if (ip->i_delayed_blks > 0) {
1602 error = filemap_flush(VFS_I(ip)->i_mapping);
1603 if (error)
1604 return error;
1605 }
1606 }
1607 }
1608
1609 if (VFS_I(ip)->i_nlink == 0)
1610 return 0;
1611
1612 if (xfs_can_free_eofblocks(ip, false)) {
1613
1614 /*
1615 * Check if the inode is being opened, written and closed
1616 * frequently and we have delayed allocation blocks outstanding
1617 * (e.g. streaming writes from the NFS server), truncating the
1618 * blocks past EOF will cause fragmentation to occur.
1619 *
1620 * In this case don't do the truncation, but we have to be
1621 * careful how we detect this case. Blocks beyond EOF show up as
1622 * i_delayed_blks even when the inode is clean, so we need to
1623 * truncate them away first before checking for a dirty release.
1624 * Hence on the first dirty close we will still remove the
1625 * speculative allocation, but after that we will leave it in
1626 * place.
1627 */
1628 if (xfs_iflags_test(ip, XFS_IDIRTY_RELEASE))
1629 return 0;
1630 /*
1631 * If we can't get the iolock just skip truncating the blocks
1632 * past EOF because we could deadlock with the mmap_lock
1633 * otherwise. We'll get another chance to drop them once the
1634 * last reference to the inode is dropped, so we'll never leak
1635 * blocks permanently.
1636 */
1637 if (xfs_ilock_nowait(ip, XFS_IOLOCK_EXCL)) {
1638 error = xfs_free_eofblocks(ip);
1639 xfs_iunlock(ip, XFS_IOLOCK_EXCL);
1640 if (error)
1641 return error;
1642 }
1643
1644 /* delalloc blocks after truncation means it really is dirty */
1645 if (ip->i_delayed_blks)
1646 xfs_iflags_set(ip, XFS_IDIRTY_RELEASE);
1647 }
1648 return 0;
1649}
1650
1651/*
1652 * xfs_inactive_truncate
1653 *
1654 * Called to perform a truncate when an inode becomes unlinked.
1655 */
1656STATIC int
1657xfs_inactive_truncate(
1658 struct xfs_inode *ip)
1659{
1660 struct xfs_mount *mp = ip->i_mount;
1661 struct xfs_trans *tp;
1662 int error;
1663
1664 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, 0, 0, 0, &tp);
1665 if (error) {
1666 ASSERT(XFS_FORCED_SHUTDOWN(mp));
1667 return error;
1668 }
1669 xfs_ilock(ip, XFS_ILOCK_EXCL);
1670 xfs_trans_ijoin(tp, ip, 0);
1671
1672 /*
1673 * Log the inode size first to prevent stale data exposure in the event
1674 * of a system crash before the truncate completes. See the related
1675 * comment in xfs_vn_setattr_size() for details.
1676 */
1677 ip->i_d.di_size = 0;
1678 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1679
1680 error = xfs_itruncate_extents(&tp, ip, XFS_DATA_FORK, 0);
1681 if (error)
1682 goto error_trans_cancel;
1683
1684 ASSERT(ip->i_df.if_nextents == 0);
1685
1686 error = xfs_trans_commit(tp);
1687 if (error)
1688 goto error_unlock;
1689
1690 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1691 return 0;
1692
1693error_trans_cancel:
1694 xfs_trans_cancel(tp);
1695error_unlock:
1696 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1697 return error;
1698}
1699
1700/*
1701 * xfs_inactive_ifree()
1702 *
1703 * Perform the inode free when an inode is unlinked.
1704 */
1705STATIC int
1706xfs_inactive_ifree(
1707 struct xfs_inode *ip)
1708{
1709 struct xfs_mount *mp = ip->i_mount;
1710 struct xfs_trans *tp;
1711 int error;
1712
1713 /*
1714 * We try to use a per-AG reservation for any block needed by the finobt
1715 * tree, but as the finobt feature predates the per-AG reservation
1716 * support a degraded file system might not have enough space for the
1717 * reservation at mount time. In that case try to dip into the reserved
1718 * pool and pray.
1719 *
1720 * Send a warning if the reservation does happen to fail, as the inode
1721 * now remains allocated and sits on the unlinked list until the fs is
1722 * repaired.
1723 */
1724 if (unlikely(mp->m_finobt_nores)) {
1725 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ifree,
1726 XFS_IFREE_SPACE_RES(mp), 0, XFS_TRANS_RESERVE,
1727 &tp);
1728 } else {
1729 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ifree, 0, 0, 0, &tp);
1730 }
1731 if (error) {
1732 if (error == -ENOSPC) {
1733 xfs_warn_ratelimited(mp,
1734 "Failed to remove inode(s) from unlinked list. "
1735 "Please free space, unmount and run xfs_repair.");
1736 } else {
1737 ASSERT(XFS_FORCED_SHUTDOWN(mp));
1738 }
1739 return error;
1740 }
1741
1742 /*
1743 * We do not hold the inode locked across the entire rolling transaction
1744 * here. We only need to hold it for the first transaction that
1745 * xfs_ifree() builds, which may mark the inode XFS_ISTALE if the
1746 * underlying cluster buffer is freed. Relogging an XFS_ISTALE inode
1747 * here breaks the relationship between cluster buffer invalidation and
1748 * stale inode invalidation on cluster buffer item journal commit
1749 * completion, and can result in leaving dirty stale inodes hanging
1750 * around in memory.
1751 *
1752 * We have no need for serialising this inode operation against other
1753 * operations - we freed the inode and hence reallocation is required
1754 * and that will serialise on reallocating the space the deferops need
1755 * to free. Hence we can unlock the inode on the first commit of
1756 * the transaction rather than roll it right through the deferops. This
1757 * avoids relogging the XFS_ISTALE inode.
1758 *
1759 * We check that xfs_ifree() hasn't grown an internal transaction roll
1760 * by asserting that the inode is still locked when it returns.
1761 */
1762 xfs_ilock(ip, XFS_ILOCK_EXCL);
1763 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
1764
1765 error = xfs_ifree(tp, ip);
1766 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
1767 if (error) {
1768 /*
1769 * If we fail to free the inode, shut down. The cancel
1770 * might do that, we need to make sure. Otherwise the
1771 * inode might be lost for a long time or forever.
1772 */
1773 if (!XFS_FORCED_SHUTDOWN(mp)) {
1774 xfs_notice(mp, "%s: xfs_ifree returned error %d",
1775 __func__, error);
1776 xfs_force_shutdown(mp, SHUTDOWN_META_IO_ERROR);
1777 }
1778 xfs_trans_cancel(tp);
1779 return error;
1780 }
1781
1782 /*
1783 * Credit the quota account(s). The inode is gone.
1784 */
1785 xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_ICOUNT, -1);
1786
1787 /*
1788 * Just ignore errors at this point. There is nothing we can do except
1789 * to try to keep going. Make sure it's not a silent error.
1790 */
1791 error = xfs_trans_commit(tp);
1792 if (error)
1793 xfs_notice(mp, "%s: xfs_trans_commit returned error %d",
1794 __func__, error);
1795
1796 return 0;
1797}
1798
1799/*
1800 * xfs_inactive
1801 *
1802 * This is called when the vnode reference count for the vnode
1803 * goes to zero. If the file has been unlinked, then it must
1804 * now be truncated. Also, we clear all of the read-ahead state
1805 * kept for the inode here since the file is now closed.
1806 */
1807void
1808xfs_inactive(
1809 xfs_inode_t *ip)
1810{
1811 struct xfs_mount *mp;
1812 int error;
1813 int truncate = 0;
1814
1815 /*
1816 * If the inode is already free, then there can be nothing
1817 * to clean up here.
1818 */
1819 if (VFS_I(ip)->i_mode == 0) {
1820 ASSERT(ip->i_df.if_broot_bytes == 0);
1821 return;
1822 }
1823
1824 mp = ip->i_mount;
1825 ASSERT(!xfs_iflags_test(ip, XFS_IRECOVERY));
1826
1827 /* If this is a read-only mount, don't do this (would generate I/O) */
1828 if (mp->m_flags & XFS_MOUNT_RDONLY)
1829 return;
1830
1831 /* Try to clean out the cow blocks if there are any. */
1832 if (xfs_inode_has_cow_data(ip))
1833 xfs_reflink_cancel_cow_range(ip, 0, NULLFILEOFF, true);
1834
1835 if (VFS_I(ip)->i_nlink != 0) {
1836 /*
1837 * force is true because we are evicting an inode from the
1838 * cache. Post-eof blocks must be freed, lest we end up with
1839 * broken free space accounting.
1840 *
1841 * Note: don't bother with iolock here since lockdep complains
1842 * about acquiring it in reclaim context. We have the only
1843 * reference to the inode at this point anyways.
1844 */
1845 if (xfs_can_free_eofblocks(ip, true))
1846 xfs_free_eofblocks(ip);
1847
1848 return;
1849 }
1850
1851 if (S_ISREG(VFS_I(ip)->i_mode) &&
1852 (ip->i_d.di_size != 0 || XFS_ISIZE(ip) != 0 ||
1853 ip->i_df.if_nextents > 0 || ip->i_delayed_blks > 0))
1854 truncate = 1;
1855
1856 error = xfs_qm_dqattach(ip);
1857 if (error)
1858 return;
1859
1860 if (S_ISLNK(VFS_I(ip)->i_mode))
1861 error = xfs_inactive_symlink(ip);
1862 else if (truncate)
1863 error = xfs_inactive_truncate(ip);
1864 if (error)
1865 return;
1866
1867 /*
1868 * If there are attributes associated with the file then blow them away
1869 * now. The code calls a routine that recursively deconstructs the
1870 * attribute fork. If also blows away the in-core attribute fork.
1871 */
1872 if (XFS_IFORK_Q(ip)) {
1873 error = xfs_attr_inactive(ip);
1874 if (error)
1875 return;
1876 }
1877
1878 ASSERT(!ip->i_afp);
1879 ASSERT(ip->i_d.di_forkoff == 0);
1880
1881 /*
1882 * Free the inode.
1883 */
1884 error = xfs_inactive_ifree(ip);
1885 if (error)
1886 return;
1887
1888 /*
1889 * Release the dquots held by inode, if any.
1890 */
1891 xfs_qm_dqdetach(ip);
1892}
1893
1894/*
1895 * In-Core Unlinked List Lookups
1896 * =============================
1897 *
1898 * Every inode is supposed to be reachable from some other piece of metadata
1899 * with the exception of the root directory. Inodes with a connection to a
1900 * file descriptor but not linked from anywhere in the on-disk directory tree
1901 * are collectively known as unlinked inodes, though the filesystem itself
1902 * maintains links to these inodes so that on-disk metadata are consistent.
1903 *
1904 * XFS implements a per-AG on-disk hash table of unlinked inodes. The AGI
1905 * header contains a number of buckets that point to an inode, and each inode
1906 * record has a pointer to the next inode in the hash chain. This
1907 * singly-linked list causes scaling problems in the iunlink remove function
1908 * because we must walk that list to find the inode that points to the inode
1909 * being removed from the unlinked hash bucket list.
1910 *
1911 * What if we modelled the unlinked list as a collection of records capturing
1912 * "X.next_unlinked = Y" relations? If we indexed those records on Y, we'd
1913 * have a fast way to look up unlinked list predecessors, which avoids the
1914 * slow list walk. That's exactly what we do here (in-core) with a per-AG
1915 * rhashtable.
1916 *
1917 * Because this is a backref cache, we ignore operational failures since the
1918 * iunlink code can fall back to the slow bucket walk. The only errors that
1919 * should bubble out are for obviously incorrect situations.
1920 *
1921 * All users of the backref cache MUST hold the AGI buffer lock to serialize
1922 * access or have otherwise provided for concurrency control.
1923 */
1924
1925/* Capture a "X.next_unlinked = Y" relationship. */
1926struct xfs_iunlink {
1927 struct rhash_head iu_rhash_head;
1928 xfs_agino_t iu_agino; /* X */
1929 xfs_agino_t iu_next_unlinked; /* Y */
1930};
1931
1932/* Unlinked list predecessor lookup hashtable construction */
1933static int
1934xfs_iunlink_obj_cmpfn(
1935 struct rhashtable_compare_arg *arg,
1936 const void *obj)
1937{
1938 const xfs_agino_t *key = arg->key;
1939 const struct xfs_iunlink *iu = obj;
1940
1941 if (iu->iu_next_unlinked != *key)
1942 return 1;
1943 return 0;
1944}
1945
1946static const struct rhashtable_params xfs_iunlink_hash_params = {
1947 .min_size = XFS_AGI_UNLINKED_BUCKETS,
1948 .key_len = sizeof(xfs_agino_t),
1949 .key_offset = offsetof(struct xfs_iunlink,
1950 iu_next_unlinked),
1951 .head_offset = offsetof(struct xfs_iunlink, iu_rhash_head),
1952 .automatic_shrinking = true,
1953 .obj_cmpfn = xfs_iunlink_obj_cmpfn,
1954};
1955
1956/*
1957 * Return X, where X.next_unlinked == @agino. Returns NULLAGINO if no such
1958 * relation is found.
1959 */
1960static xfs_agino_t
1961xfs_iunlink_lookup_backref(
1962 struct xfs_perag *pag,
1963 xfs_agino_t agino)
1964{
1965 struct xfs_iunlink *iu;
1966
1967 iu = rhashtable_lookup_fast(&pag->pagi_unlinked_hash, &agino,
1968 xfs_iunlink_hash_params);
1969 return iu ? iu->iu_agino : NULLAGINO;
1970}
1971
1972/*
1973 * Take ownership of an iunlink cache entry and insert it into the hash table.
1974 * If successful, the entry will be owned by the cache; if not, it is freed.
1975 * Either way, the caller does not own @iu after this call.
1976 */
1977static int
1978xfs_iunlink_insert_backref(
1979 struct xfs_perag *pag,
1980 struct xfs_iunlink *iu)
1981{
1982 int error;
1983
1984 error = rhashtable_insert_fast(&pag->pagi_unlinked_hash,
1985 &iu->iu_rhash_head, xfs_iunlink_hash_params);
1986 /*
1987 * Fail loudly if there already was an entry because that's a sign of
1988 * corruption of in-memory data. Also fail loudly if we see an error
1989 * code we didn't anticipate from the rhashtable code. Currently we
1990 * only anticipate ENOMEM.
1991 */
1992 if (error) {
1993 WARN(error != -ENOMEM, "iunlink cache insert error %d", error);
1994 kmem_free(iu);
1995 }
1996 /*
1997 * Absorb any runtime errors that aren't a result of corruption because
1998 * this is a cache and we can always fall back to bucket list scanning.
1999 */
2000 if (error != 0 && error != -EEXIST)
2001 error = 0;
2002 return error;
2003}
2004
2005/* Remember that @prev_agino.next_unlinked = @this_agino. */
2006static int
2007xfs_iunlink_add_backref(
2008 struct xfs_perag *pag,
2009 xfs_agino_t prev_agino,
2010 xfs_agino_t this_agino)
2011{
2012 struct xfs_iunlink *iu;
2013
2014 if (XFS_TEST_ERROR(false, pag->pag_mount, XFS_ERRTAG_IUNLINK_FALLBACK))
2015 return 0;
2016
2017 iu = kmem_zalloc(sizeof(*iu), KM_NOFS);
2018 iu->iu_agino = prev_agino;
2019 iu->iu_next_unlinked = this_agino;
2020
2021 return xfs_iunlink_insert_backref(pag, iu);
2022}
2023
2024/*
2025 * Replace X.next_unlinked = @agino with X.next_unlinked = @next_unlinked.
2026 * If @next_unlinked is NULLAGINO, we drop the backref and exit. If there
2027 * wasn't any such entry then we don't bother.
2028 */
2029static int
2030xfs_iunlink_change_backref(
2031 struct xfs_perag *pag,
2032 xfs_agino_t agino,
2033 xfs_agino_t next_unlinked)
2034{
2035 struct xfs_iunlink *iu;
2036 int error;
2037
2038 /* Look up the old entry; if there wasn't one then exit. */
2039 iu = rhashtable_lookup_fast(&pag->pagi_unlinked_hash, &agino,
2040 xfs_iunlink_hash_params);
2041 if (!iu)
2042 return 0;
2043
2044 /*
2045 * Remove the entry. This shouldn't ever return an error, but if we
2046 * couldn't remove the old entry we don't want to add it again to the
2047 * hash table, and if the entry disappeared on us then someone's
2048 * violated the locking rules and we need to fail loudly. Either way
2049 * we cannot remove the inode because internal state is or would have
2050 * been corrupt.
2051 */
2052 error = rhashtable_remove_fast(&pag->pagi_unlinked_hash,
2053 &iu->iu_rhash_head, xfs_iunlink_hash_params);
2054 if (error)
2055 return error;
2056
2057 /* If there is no new next entry just free our item and return. */
2058 if (next_unlinked == NULLAGINO) {
2059 kmem_free(iu);
2060 return 0;
2061 }
2062
2063 /* Update the entry and re-add it to the hash table. */
2064 iu->iu_next_unlinked = next_unlinked;
2065 return xfs_iunlink_insert_backref(pag, iu);
2066}
2067
2068/* Set up the in-core predecessor structures. */
2069int
2070xfs_iunlink_init(
2071 struct xfs_perag *pag)
2072{
2073 return rhashtable_init(&pag->pagi_unlinked_hash,
2074 &xfs_iunlink_hash_params);
2075}
2076
2077/* Free the in-core predecessor structures. */
2078static void
2079xfs_iunlink_free_item(
2080 void *ptr,
2081 void *arg)
2082{
2083 struct xfs_iunlink *iu = ptr;
2084 bool *freed_anything = arg;
2085
2086 *freed_anything = true;
2087 kmem_free(iu);
2088}
2089
2090void
2091xfs_iunlink_destroy(
2092 struct xfs_perag *pag)
2093{
2094 bool freed_anything = false;
2095
2096 rhashtable_free_and_destroy(&pag->pagi_unlinked_hash,
2097 xfs_iunlink_free_item, &freed_anything);
2098
2099 ASSERT(freed_anything == false || XFS_FORCED_SHUTDOWN(pag->pag_mount));
2100}
2101
2102/*
2103 * Point the AGI unlinked bucket at an inode and log the results. The caller
2104 * is responsible for validating the old value.
2105 */
2106STATIC int
2107xfs_iunlink_update_bucket(
2108 struct xfs_trans *tp,
2109 xfs_agnumber_t agno,
2110 struct xfs_buf *agibp,
2111 unsigned int bucket_index,
2112 xfs_agino_t new_agino)
2113{
2114 struct xfs_agi *agi = agibp->b_addr;
2115 xfs_agino_t old_value;
2116 int offset;
2117
2118 ASSERT(xfs_verify_agino_or_null(tp->t_mountp, agno, new_agino));
2119
2120 old_value = be32_to_cpu(agi->agi_unlinked[bucket_index]);
2121 trace_xfs_iunlink_update_bucket(tp->t_mountp, agno, bucket_index,
2122 old_value, new_agino);
2123
2124 /*
2125 * We should never find the head of the list already set to the value
2126 * passed in because either we're adding or removing ourselves from the
2127 * head of the list.
2128 */
2129 if (old_value == new_agino) {
2130 xfs_buf_mark_corrupt(agibp);
2131 return -EFSCORRUPTED;
2132 }
2133
2134 agi->agi_unlinked[bucket_index] = cpu_to_be32(new_agino);
2135 offset = offsetof(struct xfs_agi, agi_unlinked) +
2136 (sizeof(xfs_agino_t) * bucket_index);
2137 xfs_trans_log_buf(tp, agibp, offset, offset + sizeof(xfs_agino_t) - 1);
2138 return 0;
2139}
2140
2141/* Set an on-disk inode's next_unlinked pointer. */
2142STATIC void
2143xfs_iunlink_update_dinode(
2144 struct xfs_trans *tp,
2145 xfs_agnumber_t agno,
2146 xfs_agino_t agino,
2147 struct xfs_buf *ibp,
2148 struct xfs_dinode *dip,
2149 struct xfs_imap *imap,
2150 xfs_agino_t next_agino)
2151{
2152 struct xfs_mount *mp = tp->t_mountp;
2153 int offset;
2154
2155 ASSERT(xfs_verify_agino_or_null(mp, agno, next_agino));
2156
2157 trace_xfs_iunlink_update_dinode(mp, agno, agino,
2158 be32_to_cpu(dip->di_next_unlinked), next_agino);
2159
2160 dip->di_next_unlinked = cpu_to_be32(next_agino);
2161 offset = imap->im_boffset +
2162 offsetof(struct xfs_dinode, di_next_unlinked);
2163
2164 /* need to recalc the inode CRC if appropriate */
2165 xfs_dinode_calc_crc(mp, dip);
2166 xfs_trans_inode_buf(tp, ibp);
2167 xfs_trans_log_buf(tp, ibp, offset, offset + sizeof(xfs_agino_t) - 1);
2168}
2169
2170/* Set an in-core inode's unlinked pointer and return the old value. */
2171STATIC int
2172xfs_iunlink_update_inode(
2173 struct xfs_trans *tp,
2174 struct xfs_inode *ip,
2175 xfs_agnumber_t agno,
2176 xfs_agino_t next_agino,
2177 xfs_agino_t *old_next_agino)
2178{
2179 struct xfs_mount *mp = tp->t_mountp;
2180 struct xfs_dinode *dip;
2181 struct xfs_buf *ibp;
2182 xfs_agino_t old_value;
2183 int error;
2184
2185 ASSERT(xfs_verify_agino_or_null(mp, agno, next_agino));
2186
2187 error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &ibp, 0);
2188 if (error)
2189 return error;
2190
2191 /* Make sure the old pointer isn't garbage. */
2192 old_value = be32_to_cpu(dip->di_next_unlinked);
2193 if (!xfs_verify_agino_or_null(mp, agno, old_value)) {
2194 xfs_inode_verifier_error(ip, -EFSCORRUPTED, __func__, dip,
2195 sizeof(*dip), __this_address);
2196 error = -EFSCORRUPTED;
2197 goto out;
2198 }
2199
2200 /*
2201 * Since we're updating a linked list, we should never find that the
2202 * current pointer is the same as the new value, unless we're
2203 * terminating the list.
2204 */
2205 *old_next_agino = old_value;
2206 if (old_value == next_agino) {
2207 if (next_agino != NULLAGINO) {
2208 xfs_inode_verifier_error(ip, -EFSCORRUPTED, __func__,
2209 dip, sizeof(*dip), __this_address);
2210 error = -EFSCORRUPTED;
2211 }
2212 goto out;
2213 }
2214
2215 /* Ok, update the new pointer. */
2216 xfs_iunlink_update_dinode(tp, agno, XFS_INO_TO_AGINO(mp, ip->i_ino),
2217 ibp, dip, &ip->i_imap, next_agino);
2218 return 0;
2219out:
2220 xfs_trans_brelse(tp, ibp);
2221 return error;
2222}
2223
2224/*
2225 * This is called when the inode's link count has gone to 0 or we are creating
2226 * a tmpfile via O_TMPFILE. The inode @ip must have nlink == 0.
2227 *
2228 * We place the on-disk inode on a list in the AGI. It will be pulled from this
2229 * list when the inode is freed.
2230 */
2231STATIC int
2232xfs_iunlink(
2233 struct xfs_trans *tp,
2234 struct xfs_inode *ip)
2235{
2236 struct xfs_mount *mp = tp->t_mountp;
2237 struct xfs_agi *agi;
2238 struct xfs_buf *agibp;
2239 xfs_agino_t next_agino;
2240 xfs_agnumber_t agno = XFS_INO_TO_AGNO(mp, ip->i_ino);
2241 xfs_agino_t agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
2242 short bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
2243 int error;
2244
2245 ASSERT(VFS_I(ip)->i_nlink == 0);
2246 ASSERT(VFS_I(ip)->i_mode != 0);
2247 trace_xfs_iunlink(ip);
2248
2249 /* Get the agi buffer first. It ensures lock ordering on the list. */
2250 error = xfs_read_agi(mp, tp, agno, &agibp);
2251 if (error)
2252 return error;
2253 agi = agibp->b_addr;
2254
2255 /*
2256 * Get the index into the agi hash table for the list this inode will
2257 * go on. Make sure the pointer isn't garbage and that this inode
2258 * isn't already on the list.
2259 */
2260 next_agino = be32_to_cpu(agi->agi_unlinked[bucket_index]);
2261 if (next_agino == agino ||
2262 !xfs_verify_agino_or_null(mp, agno, next_agino)) {
2263 xfs_buf_mark_corrupt(agibp);
2264 return -EFSCORRUPTED;
2265 }
2266
2267 if (next_agino != NULLAGINO) {
2268 xfs_agino_t old_agino;
2269
2270 /*
2271 * There is already another inode in the bucket, so point this
2272 * inode to the current head of the list.
2273 */
2274 error = xfs_iunlink_update_inode(tp, ip, agno, next_agino,
2275 &old_agino);
2276 if (error)
2277 return error;
2278 ASSERT(old_agino == NULLAGINO);
2279
2280 /*
2281 * agino has been unlinked, add a backref from the next inode
2282 * back to agino.
2283 */
2284 error = xfs_iunlink_add_backref(agibp->b_pag, agino, next_agino);
2285 if (error)
2286 return error;
2287 }
2288
2289 /* Point the head of the list to point to this inode. */
2290 return xfs_iunlink_update_bucket(tp, agno, agibp, bucket_index, agino);
2291}
2292
2293/* Return the imap, dinode pointer, and buffer for an inode. */
2294STATIC int
2295xfs_iunlink_map_ino(
2296 struct xfs_trans *tp,
2297 xfs_agnumber_t agno,
2298 xfs_agino_t agino,
2299 struct xfs_imap *imap,
2300 struct xfs_dinode **dipp,
2301 struct xfs_buf **bpp)
2302{
2303 struct xfs_mount *mp = tp->t_mountp;
2304 int error;
2305
2306 imap->im_blkno = 0;
2307 error = xfs_imap(mp, tp, XFS_AGINO_TO_INO(mp, agno, agino), imap, 0);
2308 if (error) {
2309 xfs_warn(mp, "%s: xfs_imap returned error %d.",
2310 __func__, error);
2311 return error;
2312 }
2313
2314 error = xfs_imap_to_bp(mp, tp, imap, dipp, bpp, 0);
2315 if (error) {
2316 xfs_warn(mp, "%s: xfs_imap_to_bp returned error %d.",
2317 __func__, error);
2318 return error;
2319 }
2320
2321 return 0;
2322}
2323
2324/*
2325 * Walk the unlinked chain from @head_agino until we find the inode that
2326 * points to @target_agino. Return the inode number, map, dinode pointer,
2327 * and inode cluster buffer of that inode as @agino, @imap, @dipp, and @bpp.
2328 *
2329 * @tp, @pag, @head_agino, and @target_agino are input parameters.
2330 * @agino, @imap, @dipp, and @bpp are all output parameters.
2331 *
2332 * Do not call this function if @target_agino is the head of the list.
2333 */
2334STATIC int
2335xfs_iunlink_map_prev(
2336 struct xfs_trans *tp,
2337 xfs_agnumber_t agno,
2338 xfs_agino_t head_agino,
2339 xfs_agino_t target_agino,
2340 xfs_agino_t *agino,
2341 struct xfs_imap *imap,
2342 struct xfs_dinode **dipp,
2343 struct xfs_buf **bpp,
2344 struct xfs_perag *pag)
2345{
2346 struct xfs_mount *mp = tp->t_mountp;
2347 xfs_agino_t next_agino;
2348 int error;
2349
2350 ASSERT(head_agino != target_agino);
2351 *bpp = NULL;
2352
2353 /* See if our backref cache can find it faster. */
2354 *agino = xfs_iunlink_lookup_backref(pag, target_agino);
2355 if (*agino != NULLAGINO) {
2356 error = xfs_iunlink_map_ino(tp, agno, *agino, imap, dipp, bpp);
2357 if (error)
2358 return error;
2359
2360 if (be32_to_cpu((*dipp)->di_next_unlinked) == target_agino)
2361 return 0;
2362
2363 /*
2364 * If we get here the cache contents were corrupt, so drop the
2365 * buffer and fall back to walking the bucket list.
2366 */
2367 xfs_trans_brelse(tp, *bpp);
2368 *bpp = NULL;
2369 WARN_ON_ONCE(1);
2370 }
2371
2372 trace_xfs_iunlink_map_prev_fallback(mp, agno);
2373
2374 /* Otherwise, walk the entire bucket until we find it. */
2375 next_agino = head_agino;
2376 while (next_agino != target_agino) {
2377 xfs_agino_t unlinked_agino;
2378
2379 if (*bpp)
2380 xfs_trans_brelse(tp, *bpp);
2381
2382 *agino = next_agino;
2383 error = xfs_iunlink_map_ino(tp, agno, next_agino, imap, dipp,
2384 bpp);
2385 if (error)
2386 return error;
2387
2388 unlinked_agino = be32_to_cpu((*dipp)->di_next_unlinked);
2389 /*
2390 * Make sure this pointer is valid and isn't an obvious
2391 * infinite loop.
2392 */
2393 if (!xfs_verify_agino(mp, agno, unlinked_agino) ||
2394 next_agino == unlinked_agino) {
2395 XFS_CORRUPTION_ERROR(__func__,
2396 XFS_ERRLEVEL_LOW, mp,
2397 *dipp, sizeof(**dipp));
2398 error = -EFSCORRUPTED;
2399 return error;
2400 }
2401 next_agino = unlinked_agino;
2402 }
2403
2404 return 0;
2405}
2406
2407/*
2408 * Pull the on-disk inode from the AGI unlinked list.
2409 */
2410STATIC int
2411xfs_iunlink_remove(
2412 struct xfs_trans *tp,
2413 struct xfs_inode *ip)
2414{
2415 struct xfs_mount *mp = tp->t_mountp;
2416 struct xfs_agi *agi;
2417 struct xfs_buf *agibp;
2418 struct xfs_buf *last_ibp;
2419 struct xfs_dinode *last_dip = NULL;
2420 xfs_agnumber_t agno = XFS_INO_TO_AGNO(mp, ip->i_ino);
2421 xfs_agino_t agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
2422 xfs_agino_t next_agino;
2423 xfs_agino_t head_agino;
2424 short bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
2425 int error;
2426
2427 trace_xfs_iunlink_remove(ip);
2428
2429 /* Get the agi buffer first. It ensures lock ordering on the list. */
2430 error = xfs_read_agi(mp, tp, agno, &agibp);
2431 if (error)
2432 return error;
2433 agi = agibp->b_addr;
2434
2435 /*
2436 * Get the index into the agi hash table for the list this inode will
2437 * go on. Make sure the head pointer isn't garbage.
2438 */
2439 head_agino = be32_to_cpu(agi->agi_unlinked[bucket_index]);
2440 if (!xfs_verify_agino(mp, agno, head_agino)) {
2441 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
2442 agi, sizeof(*agi));
2443 return -EFSCORRUPTED;
2444 }
2445
2446 /*
2447 * Set our inode's next_unlinked pointer to NULL and then return
2448 * the old pointer value so that we can update whatever was previous
2449 * to us in the list to point to whatever was next in the list.
2450 */
2451 error = xfs_iunlink_update_inode(tp, ip, agno, NULLAGINO, &next_agino);
2452 if (error)
2453 return error;
2454
2455 /*
2456 * If there was a backref pointing from the next inode back to this
2457 * one, remove it because we've removed this inode from the list.
2458 *
2459 * Later, if this inode was in the middle of the list we'll update
2460 * this inode's backref to point from the next inode.
2461 */
2462 if (next_agino != NULLAGINO) {
2463 error = xfs_iunlink_change_backref(agibp->b_pag, next_agino,
2464 NULLAGINO);
2465 if (error)
2466 return error;
2467 }
2468
2469 if (head_agino != agino) {
2470 struct xfs_imap imap;
2471 xfs_agino_t prev_agino;
2472
2473 /* We need to search the list for the inode being freed. */
2474 error = xfs_iunlink_map_prev(tp, agno, head_agino, agino,
2475 &prev_agino, &imap, &last_dip, &last_ibp,
2476 agibp->b_pag);
2477 if (error)
2478 return error;
2479
2480 /* Point the previous inode on the list to the next inode. */
2481 xfs_iunlink_update_dinode(tp, agno, prev_agino, last_ibp,
2482 last_dip, &imap, next_agino);
2483
2484 /*
2485 * Now we deal with the backref for this inode. If this inode
2486 * pointed at a real inode, change the backref that pointed to
2487 * us to point to our old next. If this inode was the end of
2488 * the list, delete the backref that pointed to us. Note that
2489 * change_backref takes care of deleting the backref if
2490 * next_agino is NULLAGINO.
2491 */
2492 return xfs_iunlink_change_backref(agibp->b_pag, agino,
2493 next_agino);
2494 }
2495
2496 /* Point the head of the list to the next unlinked inode. */
2497 return xfs_iunlink_update_bucket(tp, agno, agibp, bucket_index,
2498 next_agino);
2499}
2500
2501/*
2502 * Look up the inode number specified and if it is not already marked XFS_ISTALE
2503 * mark it stale. We should only find clean inodes in this lookup that aren't
2504 * already stale.
2505 */
2506static void
2507xfs_ifree_mark_inode_stale(
2508 struct xfs_buf *bp,
2509 struct xfs_inode *free_ip,
2510 xfs_ino_t inum)
2511{
2512 struct xfs_mount *mp = bp->b_mount;
2513 struct xfs_perag *pag = bp->b_pag;
2514 struct xfs_inode_log_item *iip;
2515 struct xfs_inode *ip;
2516
2517retry:
2518 rcu_read_lock();
2519 ip = radix_tree_lookup(&pag->pag_ici_root, XFS_INO_TO_AGINO(mp, inum));
2520
2521 /* Inode not in memory, nothing to do */
2522 if (!ip) {
2523 rcu_read_unlock();
2524 return;
2525 }
2526
2527 /*
2528 * because this is an RCU protected lookup, we could find a recently
2529 * freed or even reallocated inode during the lookup. We need to check
2530 * under the i_flags_lock for a valid inode here. Skip it if it is not
2531 * valid, the wrong inode or stale.
2532 */
2533 spin_lock(&ip->i_flags_lock);
2534 if (ip->i_ino != inum || __xfs_iflags_test(ip, XFS_ISTALE)) {
2535 spin_unlock(&ip->i_flags_lock);
2536 rcu_read_unlock();
2537 return;
2538 }
2539
2540 /*
2541 * Don't try to lock/unlock the current inode, but we _cannot_ skip the
2542 * other inodes that we did not find in the list attached to the buffer
2543 * and are not already marked stale. If we can't lock it, back off and
2544 * retry.
2545 */
2546 if (ip != free_ip) {
2547 if (!xfs_ilock_nowait(ip, XFS_ILOCK_EXCL)) {
2548 spin_unlock(&ip->i_flags_lock);
2549 rcu_read_unlock();
2550 delay(1);
2551 goto retry;
2552 }
2553 }
2554 ip->i_flags |= XFS_ISTALE;
2555 spin_unlock(&ip->i_flags_lock);
2556 rcu_read_unlock();
2557
2558 /*
2559 * If we can't get the flush lock, the inode is already attached. All
2560 * we needed to do here is mark the inode stale so buffer IO completion
2561 * will remove it from the AIL.
2562 */
2563 iip = ip->i_itemp;
2564 if (!xfs_iflock_nowait(ip)) {
2565 ASSERT(!list_empty(&iip->ili_item.li_bio_list));
2566 ASSERT(iip->ili_last_fields);
2567 goto out_iunlock;
2568 }
2569
2570 /*
2571 * Inodes not attached to the buffer can be released immediately.
2572 * Everything else has to go through xfs_iflush_abort() on journal
2573 * commit as the flock synchronises removal of the inode from the
2574 * cluster buffer against inode reclaim.
2575 */
2576 if (!iip || list_empty(&iip->ili_item.li_bio_list)) {
2577 xfs_ifunlock(ip);
2578 goto out_iunlock;
2579 }
2580
2581 /* we have a dirty inode in memory that has not yet been flushed. */
2582 spin_lock(&iip->ili_lock);
2583 iip->ili_last_fields = iip->ili_fields;
2584 iip->ili_fields = 0;
2585 iip->ili_fsync_fields = 0;
2586 spin_unlock(&iip->ili_lock);
2587 ASSERT(iip->ili_last_fields);
2588
2589out_iunlock:
2590 if (ip != free_ip)
2591 xfs_iunlock(ip, XFS_ILOCK_EXCL);
2592}
2593
2594/*
2595 * A big issue when freeing the inode cluster is that we _cannot_ skip any
2596 * inodes that are in memory - they all must be marked stale and attached to
2597 * the cluster buffer.
2598 */
2599STATIC int
2600xfs_ifree_cluster(
2601 struct xfs_inode *free_ip,
2602 struct xfs_trans *tp,
2603 struct xfs_icluster *xic)
2604{
2605 struct xfs_mount *mp = free_ip->i_mount;
2606 struct xfs_ino_geometry *igeo = M_IGEO(mp);
2607 struct xfs_buf *bp;
2608 xfs_daddr_t blkno;
2609 xfs_ino_t inum = xic->first_ino;
2610 int nbufs;
2611 int i, j;
2612 int ioffset;
2613 int error;
2614
2615 nbufs = igeo->ialloc_blks / igeo->blocks_per_cluster;
2616
2617 for (j = 0; j < nbufs; j++, inum += igeo->inodes_per_cluster) {
2618 /*
2619 * The allocation bitmap tells us which inodes of the chunk were
2620 * physically allocated. Skip the cluster if an inode falls into
2621 * a sparse region.
2622 */
2623 ioffset = inum - xic->first_ino;
2624 if ((xic->alloc & XFS_INOBT_MASK(ioffset)) == 0) {
2625 ASSERT(ioffset % igeo->inodes_per_cluster == 0);
2626 continue;
2627 }
2628
2629 blkno = XFS_AGB_TO_DADDR(mp, XFS_INO_TO_AGNO(mp, inum),
2630 XFS_INO_TO_AGBNO(mp, inum));
2631
2632 /*
2633 * We obtain and lock the backing buffer first in the process
2634 * here, as we have to ensure that any dirty inode that we
2635 * can't get the flush lock on is attached to the buffer.
2636 * If we scan the in-memory inodes first, then buffer IO can
2637 * complete before we get a lock on it, and hence we may fail
2638 * to mark all the active inodes on the buffer stale.
2639 */
2640 error = xfs_trans_get_buf(tp, mp->m_ddev_targp, blkno,
2641 mp->m_bsize * igeo->blocks_per_cluster,
2642 XBF_UNMAPPED, &bp);
2643 if (error)
2644 return error;
2645
2646 /*
2647 * This buffer may not have been correctly initialised as we
2648 * didn't read it from disk. That's not important because we are
2649 * only using to mark the buffer as stale in the log, and to
2650 * attach stale cached inodes on it. That means it will never be
2651 * dispatched for IO. If it is, we want to know about it, and we
2652 * want it to fail. We can acheive this by adding a write
2653 * verifier to the buffer.
2654 */
2655 bp->b_ops = &xfs_inode_buf_ops;
2656
2657 /*
2658 * Now we need to set all the cached clean inodes as XFS_ISTALE,
2659 * too. This requires lookups, and will skip inodes that we've
2660 * already marked XFS_ISTALE.
2661 */
2662 for (i = 0; i < igeo->inodes_per_cluster; i++)
2663 xfs_ifree_mark_inode_stale(bp, free_ip, inum + i);
2664
2665 xfs_trans_stale_inode_buf(tp, bp);
2666 xfs_trans_binval(tp, bp);
2667 }
2668 return 0;
2669}
2670
2671/*
2672 * This is called to return an inode to the inode free list.
2673 * The inode should already be truncated to 0 length and have
2674 * no pages associated with it. This routine also assumes that
2675 * the inode is already a part of the transaction.
2676 *
2677 * The on-disk copy of the inode will have been added to the list
2678 * of unlinked inodes in the AGI. We need to remove the inode from
2679 * that list atomically with respect to freeing it here.
2680 */
2681int
2682xfs_ifree(
2683 struct xfs_trans *tp,
2684 struct xfs_inode *ip)
2685{
2686 int error;
2687 struct xfs_icluster xic = { 0 };
2688 struct xfs_inode_log_item *iip = ip->i_itemp;
2689
2690 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
2691 ASSERT(VFS_I(ip)->i_nlink == 0);
2692 ASSERT(ip->i_df.if_nextents == 0);
2693 ASSERT(ip->i_d.di_size == 0 || !S_ISREG(VFS_I(ip)->i_mode));
2694 ASSERT(ip->i_d.di_nblocks == 0);
2695
2696 /*
2697 * Pull the on-disk inode from the AGI unlinked list.
2698 */
2699 error = xfs_iunlink_remove(tp, ip);
2700 if (error)
2701 return error;
2702
2703 error = xfs_difree(tp, ip->i_ino, &xic);
2704 if (error)
2705 return error;
2706
2707 /*
2708 * Free any local-format data sitting around before we reset the
2709 * data fork to extents format. Note that the attr fork data has
2710 * already been freed by xfs_attr_inactive.
2711 */
2712 if (ip->i_df.if_format == XFS_DINODE_FMT_LOCAL) {
2713 kmem_free(ip->i_df.if_u1.if_data);
2714 ip->i_df.if_u1.if_data = NULL;
2715 ip->i_df.if_bytes = 0;
2716 }
2717
2718 VFS_I(ip)->i_mode = 0; /* mark incore inode as free */
2719 ip->i_d.di_flags = 0;
2720 ip->i_d.di_flags2 = 0;
2721 ip->i_d.di_dmevmask = 0;
2722 ip->i_d.di_forkoff = 0; /* mark the attr fork not in use */
2723 ip->i_df.if_format = XFS_DINODE_FMT_EXTENTS;
2724
2725 /* Don't attempt to replay owner changes for a deleted inode */
2726 spin_lock(&iip->ili_lock);
2727 iip->ili_fields &= ~(XFS_ILOG_AOWNER | XFS_ILOG_DOWNER);
2728 spin_unlock(&iip->ili_lock);
2729
2730 /*
2731 * Bump the generation count so no one will be confused
2732 * by reincarnations of this inode.
2733 */
2734 VFS_I(ip)->i_generation++;
2735 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
2736
2737 if (xic.deleted)
2738 error = xfs_ifree_cluster(ip, tp, &xic);
2739
2740 return error;
2741}
2742
2743/*
2744 * This is called to unpin an inode. The caller must have the inode locked
2745 * in at least shared mode so that the buffer cannot be subsequently pinned
2746 * once someone is waiting for it to be unpinned.
2747 */
2748static void
2749xfs_iunpin(
2750 struct xfs_inode *ip)
2751{
2752 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
2753
2754 trace_xfs_inode_unpin_nowait(ip, _RET_IP_);
2755
2756 /* Give the log a push to start the unpinning I/O */
2757 xfs_log_force_lsn(ip->i_mount, ip->i_itemp->ili_last_lsn, 0, NULL);
2758
2759}
2760
2761static void
2762__xfs_iunpin_wait(
2763 struct xfs_inode *ip)
2764{
2765 wait_queue_head_t *wq = bit_waitqueue(&ip->i_flags, __XFS_IPINNED_BIT);
2766 DEFINE_WAIT_BIT(wait, &ip->i_flags, __XFS_IPINNED_BIT);
2767
2768 xfs_iunpin(ip);
2769
2770 do {
2771 prepare_to_wait(wq, &wait.wq_entry, TASK_UNINTERRUPTIBLE);
2772 if (xfs_ipincount(ip))
2773 io_schedule();
2774 } while (xfs_ipincount(ip));
2775 finish_wait(wq, &wait.wq_entry);
2776}
2777
2778void
2779xfs_iunpin_wait(
2780 struct xfs_inode *ip)
2781{
2782 if (xfs_ipincount(ip))
2783 __xfs_iunpin_wait(ip);
2784}
2785
2786/*
2787 * Removing an inode from the namespace involves removing the directory entry
2788 * and dropping the link count on the inode. Removing the directory entry can
2789 * result in locking an AGF (directory blocks were freed) and removing a link
2790 * count can result in placing the inode on an unlinked list which results in
2791 * locking an AGI.
2792 *
2793 * The big problem here is that we have an ordering constraint on AGF and AGI
2794 * locking - inode allocation locks the AGI, then can allocate a new extent for
2795 * new inodes, locking the AGF after the AGI. Similarly, freeing the inode
2796 * removes the inode from the unlinked list, requiring that we lock the AGI
2797 * first, and then freeing the inode can result in an inode chunk being freed
2798 * and hence freeing disk space requiring that we lock an AGF.
2799 *
2800 * Hence the ordering that is imposed by other parts of the code is AGI before
2801 * AGF. This means we cannot remove the directory entry before we drop the inode
2802 * reference count and put it on the unlinked list as this results in a lock
2803 * order of AGF then AGI, and this can deadlock against inode allocation and
2804 * freeing. Therefore we must drop the link counts before we remove the
2805 * directory entry.
2806 *
2807 * This is still safe from a transactional point of view - it is not until we
2808 * get to xfs_defer_finish() that we have the possibility of multiple
2809 * transactions in this operation. Hence as long as we remove the directory
2810 * entry and drop the link count in the first transaction of the remove
2811 * operation, there are no transactional constraints on the ordering here.
2812 */
2813int
2814xfs_remove(
2815 xfs_inode_t *dp,
2816 struct xfs_name *name,
2817 xfs_inode_t *ip)
2818{
2819 xfs_mount_t *mp = dp->i_mount;
2820 xfs_trans_t *tp = NULL;
2821 int is_dir = S_ISDIR(VFS_I(ip)->i_mode);
2822 int error = 0;
2823 uint resblks;
2824
2825 trace_xfs_remove(dp, name);
2826
2827 if (XFS_FORCED_SHUTDOWN(mp))
2828 return -EIO;
2829
2830 error = xfs_qm_dqattach(dp);
2831 if (error)
2832 goto std_return;
2833
2834 error = xfs_qm_dqattach(ip);
2835 if (error)
2836 goto std_return;
2837
2838 /*
2839 * We try to get the real space reservation first,
2840 * allowing for directory btree deletion(s) implying
2841 * possible bmap insert(s). If we can't get the space
2842 * reservation then we use 0 instead, and avoid the bmap
2843 * btree insert(s) in the directory code by, if the bmap
2844 * insert tries to happen, instead trimming the LAST
2845 * block from the directory.
2846 */
2847 resblks = XFS_REMOVE_SPACE_RES(mp);
2848 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_remove, resblks, 0, 0, &tp);
2849 if (error == -ENOSPC) {
2850 resblks = 0;
2851 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_remove, 0, 0, 0,
2852 &tp);
2853 }
2854 if (error) {
2855 ASSERT(error != -ENOSPC);
2856 goto std_return;
2857 }
2858
2859 xfs_lock_two_inodes(dp, XFS_ILOCK_EXCL, ip, XFS_ILOCK_EXCL);
2860
2861 xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
2862 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
2863
2864 /*
2865 * If we're removing a directory perform some additional validation.
2866 */
2867 if (is_dir) {
2868 ASSERT(VFS_I(ip)->i_nlink >= 2);
2869 if (VFS_I(ip)->i_nlink != 2) {
2870 error = -ENOTEMPTY;
2871 goto out_trans_cancel;
2872 }
2873 if (!xfs_dir_isempty(ip)) {
2874 error = -ENOTEMPTY;
2875 goto out_trans_cancel;
2876 }
2877
2878 /* Drop the link from ip's "..". */
2879 error = xfs_droplink(tp, dp);
2880 if (error)
2881 goto out_trans_cancel;
2882
2883 /* Drop the "." link from ip to self. */
2884 error = xfs_droplink(tp, ip);
2885 if (error)
2886 goto out_trans_cancel;
2887 } else {
2888 /*
2889 * When removing a non-directory we need to log the parent
2890 * inode here. For a directory this is done implicitly
2891 * by the xfs_droplink call for the ".." entry.
2892 */
2893 xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
2894 }
2895 xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2896
2897 /* Drop the link from dp to ip. */
2898 error = xfs_droplink(tp, ip);
2899 if (error)
2900 goto out_trans_cancel;
2901
2902 error = xfs_dir_removename(tp, dp, name, ip->i_ino, resblks);
2903 if (error) {
2904 ASSERT(error != -ENOENT);
2905 goto out_trans_cancel;
2906 }
2907
2908 /*
2909 * If this is a synchronous mount, make sure that the
2910 * remove transaction goes to disk before returning to
2911 * the user.
2912 */
2913 if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
2914 xfs_trans_set_sync(tp);
2915
2916 error = xfs_trans_commit(tp);
2917 if (error)
2918 goto std_return;
2919
2920 if (is_dir && xfs_inode_is_filestream(ip))
2921 xfs_filestream_deassociate(ip);
2922
2923 return 0;
2924
2925 out_trans_cancel:
2926 xfs_trans_cancel(tp);
2927 std_return:
2928 return error;
2929}
2930
2931/*
2932 * Enter all inodes for a rename transaction into a sorted array.
2933 */
2934#define __XFS_SORT_INODES 5
2935STATIC void
2936xfs_sort_for_rename(
2937 struct xfs_inode *dp1, /* in: old (source) directory inode */
2938 struct xfs_inode *dp2, /* in: new (target) directory inode */
2939 struct xfs_inode *ip1, /* in: inode of old entry */
2940 struct xfs_inode *ip2, /* in: inode of new entry */
2941 struct xfs_inode *wip, /* in: whiteout inode */
2942 struct xfs_inode **i_tab,/* out: sorted array of inodes */
2943 int *num_inodes) /* in/out: inodes in array */
2944{
2945 int i, j;
2946
2947 ASSERT(*num_inodes == __XFS_SORT_INODES);
2948 memset(i_tab, 0, *num_inodes * sizeof(struct xfs_inode *));
2949
2950 /*
2951 * i_tab contains a list of pointers to inodes. We initialize
2952 * the table here & we'll sort it. We will then use it to
2953 * order the acquisition of the inode locks.
2954 *
2955 * Note that the table may contain duplicates. e.g., dp1 == dp2.
2956 */
2957 i = 0;
2958 i_tab[i++] = dp1;
2959 i_tab[i++] = dp2;
2960 i_tab[i++] = ip1;
2961 if (ip2)
2962 i_tab[i++] = ip2;
2963 if (wip)
2964 i_tab[i++] = wip;
2965 *num_inodes = i;
2966
2967 /*
2968 * Sort the elements via bubble sort. (Remember, there are at
2969 * most 5 elements to sort, so this is adequate.)
2970 */
2971 for (i = 0; i < *num_inodes; i++) {
2972 for (j = 1; j < *num_inodes; j++) {
2973 if (i_tab[j]->i_ino < i_tab[j-1]->i_ino) {
2974 struct xfs_inode *temp = i_tab[j];
2975 i_tab[j] = i_tab[j-1];
2976 i_tab[j-1] = temp;
2977 }
2978 }
2979 }
2980}
2981
2982static int
2983xfs_finish_rename(
2984 struct xfs_trans *tp)
2985{
2986 /*
2987 * If this is a synchronous mount, make sure that the rename transaction
2988 * goes to disk before returning to the user.
2989 */
2990 if (tp->t_mountp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
2991 xfs_trans_set_sync(tp);
2992
2993 return xfs_trans_commit(tp);
2994}
2995
2996/*
2997 * xfs_cross_rename()
2998 *
2999 * responsible for handling RENAME_EXCHANGE flag in renameat2() sytemcall
3000 */
3001STATIC int
3002xfs_cross_rename(
3003 struct xfs_trans *tp,
3004 struct xfs_inode *dp1,
3005 struct xfs_name *name1,
3006 struct xfs_inode *ip1,
3007 struct xfs_inode *dp2,
3008 struct xfs_name *name2,
3009 struct xfs_inode *ip2,
3010 int spaceres)
3011{
3012 int error = 0;
3013 int ip1_flags = 0;
3014 int ip2_flags = 0;
3015 int dp2_flags = 0;
3016
3017 /* Swap inode number for dirent in first parent */
3018 error = xfs_dir_replace(tp, dp1, name1, ip2->i_ino, spaceres);
3019 if (error)
3020 goto out_trans_abort;
3021
3022 /* Swap inode number for dirent in second parent */
3023 error = xfs_dir_replace(tp, dp2, name2, ip1->i_ino, spaceres);
3024 if (error)
3025 goto out_trans_abort;
3026
3027 /*
3028 * If we're renaming one or more directories across different parents,
3029 * update the respective ".." entries (and link counts) to match the new
3030 * parents.
3031 */
3032 if (dp1 != dp2) {
3033 dp2_flags = XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
3034
3035 if (S_ISDIR(VFS_I(ip2)->i_mode)) {
3036 error = xfs_dir_replace(tp, ip2, &xfs_name_dotdot,
3037 dp1->i_ino, spaceres);
3038 if (error)
3039 goto out_trans_abort;
3040
3041 /* transfer ip2 ".." reference to dp1 */
3042 if (!S_ISDIR(VFS_I(ip1)->i_mode)) {
3043 error = xfs_droplink(tp, dp2);
3044 if (error)
3045 goto out_trans_abort;
3046 xfs_bumplink(tp, dp1);
3047 }
3048
3049 /*
3050 * Although ip1 isn't changed here, userspace needs
3051 * to be warned about the change, so that applications
3052 * relying on it (like backup ones), will properly
3053 * notify the change
3054 */
3055 ip1_flags |= XFS_ICHGTIME_CHG;
3056 ip2_flags |= XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
3057 }
3058
3059 if (S_ISDIR(VFS_I(ip1)->i_mode)) {
3060 error = xfs_dir_replace(tp, ip1, &xfs_name_dotdot,
3061 dp2->i_ino, spaceres);
3062 if (error)
3063 goto out_trans_abort;
3064
3065 /* transfer ip1 ".." reference to dp2 */
3066 if (!S_ISDIR(VFS_I(ip2)->i_mode)) {
3067 error = xfs_droplink(tp, dp1);
3068 if (error)
3069 goto out_trans_abort;
3070 xfs_bumplink(tp, dp2);
3071 }
3072
3073 /*
3074 * Although ip2 isn't changed here, userspace needs
3075 * to be warned about the change, so that applications
3076 * relying on it (like backup ones), will properly
3077 * notify the change
3078 */
3079 ip1_flags |= XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
3080 ip2_flags |= XFS_ICHGTIME_CHG;
3081 }
3082 }
3083
3084 if (ip1_flags) {
3085 xfs_trans_ichgtime(tp, ip1, ip1_flags);
3086 xfs_trans_log_inode(tp, ip1, XFS_ILOG_CORE);
3087 }
3088 if (ip2_flags) {
3089 xfs_trans_ichgtime(tp, ip2, ip2_flags);
3090 xfs_trans_log_inode(tp, ip2, XFS_ILOG_CORE);
3091 }
3092 if (dp2_flags) {
3093 xfs_trans_ichgtime(tp, dp2, dp2_flags);
3094 xfs_trans_log_inode(tp, dp2, XFS_ILOG_CORE);
3095 }
3096 xfs_trans_ichgtime(tp, dp1, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
3097 xfs_trans_log_inode(tp, dp1, XFS_ILOG_CORE);
3098 return xfs_finish_rename(tp);
3099
3100out_trans_abort:
3101 xfs_trans_cancel(tp);
3102 return error;
3103}
3104
3105/*
3106 * xfs_rename_alloc_whiteout()
3107 *
3108 * Return a referenced, unlinked, unlocked inode that can be used as a
3109 * whiteout in a rename transaction. We use a tmpfile inode here so that if we
3110 * crash between allocating the inode and linking it into the rename transaction
3111 * recovery will free the inode and we won't leak it.
3112 */
3113static int
3114xfs_rename_alloc_whiteout(
3115 struct xfs_inode *dp,
3116 struct xfs_inode **wip)
3117{
3118 struct xfs_inode *tmpfile;
3119 int error;
3120
3121 error = xfs_create_tmpfile(dp, S_IFCHR | WHITEOUT_MODE, &tmpfile);
3122 if (error)
3123 return error;
3124
3125 /*
3126 * Prepare the tmpfile inode as if it were created through the VFS.
3127 * Complete the inode setup and flag it as linkable. nlink is already
3128 * zero, so we can skip the drop_nlink.
3129 */
3130 xfs_setup_iops(tmpfile);
3131 xfs_finish_inode_setup(tmpfile);
3132 VFS_I(tmpfile)->i_state |= I_LINKABLE;
3133
3134 *wip = tmpfile;
3135 return 0;
3136}
3137
3138/*
3139 * xfs_rename
3140 */
3141int
3142xfs_rename(
3143 struct xfs_inode *src_dp,
3144 struct xfs_name *src_name,
3145 struct xfs_inode *src_ip,
3146 struct xfs_inode *target_dp,
3147 struct xfs_name *target_name,
3148 struct xfs_inode *target_ip,
3149 unsigned int flags)
3150{
3151 struct xfs_mount *mp = src_dp->i_mount;
3152 struct xfs_trans *tp;
3153 struct xfs_inode *wip = NULL; /* whiteout inode */
3154 struct xfs_inode *inodes[__XFS_SORT_INODES];
3155 struct xfs_buf *agibp;
3156 int num_inodes = __XFS_SORT_INODES;
3157 bool new_parent = (src_dp != target_dp);
3158 bool src_is_directory = S_ISDIR(VFS_I(src_ip)->i_mode);
3159 int spaceres;
3160 int error;
3161
3162 trace_xfs_rename(src_dp, target_dp, src_name, target_name);
3163
3164 if ((flags & RENAME_EXCHANGE) && !target_ip)
3165 return -EINVAL;
3166
3167 /*
3168 * If we are doing a whiteout operation, allocate the whiteout inode
3169 * we will be placing at the target and ensure the type is set
3170 * appropriately.
3171 */
3172 if (flags & RENAME_WHITEOUT) {
3173 ASSERT(!(flags & (RENAME_NOREPLACE | RENAME_EXCHANGE)));
3174 error = xfs_rename_alloc_whiteout(target_dp, &wip);
3175 if (error)
3176 return error;
3177
3178 /* setup target dirent info as whiteout */
3179 src_name->type = XFS_DIR3_FT_CHRDEV;
3180 }
3181
3182 xfs_sort_for_rename(src_dp, target_dp, src_ip, target_ip, wip,
3183 inodes, &num_inodes);
3184
3185 spaceres = XFS_RENAME_SPACE_RES(mp, target_name->len);
3186 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_rename, spaceres, 0, 0, &tp);
3187 if (error == -ENOSPC) {
3188 spaceres = 0;
3189 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_rename, 0, 0, 0,
3190 &tp);
3191 }
3192 if (error)
3193 goto out_release_wip;
3194
3195 /*
3196 * Attach the dquots to the inodes
3197 */
3198 error = xfs_qm_vop_rename_dqattach(inodes);
3199 if (error)
3200 goto out_trans_cancel;
3201
3202 /*
3203 * Lock all the participating inodes. Depending upon whether
3204 * the target_name exists in the target directory, and
3205 * whether the target directory is the same as the source
3206 * directory, we can lock from 2 to 4 inodes.
3207 */
3208 xfs_lock_inodes(inodes, num_inodes, XFS_ILOCK_EXCL);
3209
3210 /*
3211 * Join all the inodes to the transaction. From this point on,
3212 * we can rely on either trans_commit or trans_cancel to unlock
3213 * them.
3214 */
3215 xfs_trans_ijoin(tp, src_dp, XFS_ILOCK_EXCL);
3216 if (new_parent)
3217 xfs_trans_ijoin(tp, target_dp, XFS_ILOCK_EXCL);
3218 xfs_trans_ijoin(tp, src_ip, XFS_ILOCK_EXCL);
3219 if (target_ip)
3220 xfs_trans_ijoin(tp, target_ip, XFS_ILOCK_EXCL);
3221 if (wip)
3222 xfs_trans_ijoin(tp, wip, XFS_ILOCK_EXCL);
3223
3224 /*
3225 * If we are using project inheritance, we only allow renames
3226 * into our tree when the project IDs are the same; else the
3227 * tree quota mechanism would be circumvented.
3228 */
3229 if (unlikely((target_dp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) &&
3230 target_dp->i_d.di_projid != src_ip->i_d.di_projid)) {
3231 error = -EXDEV;
3232 goto out_trans_cancel;
3233 }
3234
3235 /* RENAME_EXCHANGE is unique from here on. */
3236 if (flags & RENAME_EXCHANGE)
3237 return xfs_cross_rename(tp, src_dp, src_name, src_ip,
3238 target_dp, target_name, target_ip,
3239 spaceres);
3240
3241 /*
3242 * Check for expected errors before we dirty the transaction
3243 * so we can return an error without a transaction abort.
3244 */
3245 if (target_ip == NULL) {
3246 /*
3247 * If there's no space reservation, check the entry will
3248 * fit before actually inserting it.
3249 */
3250 if (!spaceres) {
3251 error = xfs_dir_canenter(tp, target_dp, target_name);
3252 if (error)
3253 goto out_trans_cancel;
3254 }
3255 } else {
3256 /*
3257 * If target exists and it's a directory, check that whether
3258 * it can be destroyed.
3259 */
3260 if (S_ISDIR(VFS_I(target_ip)->i_mode) &&
3261 (!xfs_dir_isempty(target_ip) ||
3262 (VFS_I(target_ip)->i_nlink > 2))) {
3263 error = -EEXIST;
3264 goto out_trans_cancel;
3265 }
3266 }
3267
3268 /*
3269 * Directory entry creation below may acquire the AGF. Remove
3270 * the whiteout from the unlinked list first to preserve correct
3271 * AGI/AGF locking order. This dirties the transaction so failures
3272 * after this point will abort and log recovery will clean up the
3273 * mess.
3274 *
3275 * For whiteouts, we need to bump the link count on the whiteout
3276 * inode. After this point, we have a real link, clear the tmpfile
3277 * state flag from the inode so it doesn't accidentally get misused
3278 * in future.
3279 */
3280 if (wip) {
3281 ASSERT(VFS_I(wip)->i_nlink == 0);
3282 error = xfs_iunlink_remove(tp, wip);
3283 if (error)
3284 goto out_trans_cancel;
3285
3286 xfs_bumplink(tp, wip);
3287 VFS_I(wip)->i_state &= ~I_LINKABLE;
3288 }
3289
3290 /*
3291 * Set up the target.
3292 */
3293 if (target_ip == NULL) {
3294 /*
3295 * If target does not exist and the rename crosses
3296 * directories, adjust the target directory link count
3297 * to account for the ".." reference from the new entry.
3298 */
3299 error = xfs_dir_createname(tp, target_dp, target_name,
3300 src_ip->i_ino, spaceres);
3301 if (error)
3302 goto out_trans_cancel;
3303
3304 xfs_trans_ichgtime(tp, target_dp,
3305 XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
3306
3307 if (new_parent && src_is_directory) {
3308 xfs_bumplink(tp, target_dp);
3309 }
3310 } else { /* target_ip != NULL */
3311 /*
3312 * Link the source inode under the target name.
3313 * If the source inode is a directory and we are moving
3314 * it across directories, its ".." entry will be
3315 * inconsistent until we replace that down below.
3316 *
3317 * In case there is already an entry with the same
3318 * name at the destination directory, remove it first.
3319 */
3320
3321 /*
3322 * Check whether the replace operation will need to allocate
3323 * blocks. This happens when the shortform directory lacks
3324 * space and we have to convert it to a block format directory.
3325 * When more blocks are necessary, we must lock the AGI first
3326 * to preserve locking order (AGI -> AGF).
3327 */
3328 if (xfs_dir2_sf_replace_needblock(target_dp, src_ip->i_ino)) {
3329 error = xfs_read_agi(mp, tp,
3330 XFS_INO_TO_AGNO(mp, target_ip->i_ino),
3331 &agibp);
3332 if (error)
3333 goto out_trans_cancel;
3334 }
3335
3336 error = xfs_dir_replace(tp, target_dp, target_name,
3337 src_ip->i_ino, spaceres);
3338 if (error)
3339 goto out_trans_cancel;
3340
3341 xfs_trans_ichgtime(tp, target_dp,
3342 XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
3343
3344 /*
3345 * Decrement the link count on the target since the target
3346 * dir no longer points to it.
3347 */
3348 error = xfs_droplink(tp, target_ip);
3349 if (error)
3350 goto out_trans_cancel;
3351
3352 if (src_is_directory) {
3353 /*
3354 * Drop the link from the old "." entry.
3355 */
3356 error = xfs_droplink(tp, target_ip);
3357 if (error)
3358 goto out_trans_cancel;
3359 }
3360 } /* target_ip != NULL */
3361
3362 /*
3363 * Remove the source.
3364 */
3365 if (new_parent && src_is_directory) {
3366 /*
3367 * Rewrite the ".." entry to point to the new
3368 * directory.
3369 */
3370 error = xfs_dir_replace(tp, src_ip, &xfs_name_dotdot,
3371 target_dp->i_ino, spaceres);
3372 ASSERT(error != -EEXIST);
3373 if (error)
3374 goto out_trans_cancel;
3375 }
3376
3377 /*
3378 * We always want to hit the ctime on the source inode.
3379 *
3380 * This isn't strictly required by the standards since the source
3381 * inode isn't really being changed, but old unix file systems did
3382 * it and some incremental backup programs won't work without it.
3383 */
3384 xfs_trans_ichgtime(tp, src_ip, XFS_ICHGTIME_CHG);
3385 xfs_trans_log_inode(tp, src_ip, XFS_ILOG_CORE);
3386
3387 /*
3388 * Adjust the link count on src_dp. This is necessary when
3389 * renaming a directory, either within one parent when
3390 * the target existed, or across two parent directories.
3391 */
3392 if (src_is_directory && (new_parent || target_ip != NULL)) {
3393
3394 /*
3395 * Decrement link count on src_directory since the
3396 * entry that's moved no longer points to it.
3397 */
3398 error = xfs_droplink(tp, src_dp);
3399 if (error)
3400 goto out_trans_cancel;
3401 }
3402
3403 /*
3404 * For whiteouts, we only need to update the source dirent with the
3405 * inode number of the whiteout inode rather than removing it
3406 * altogether.
3407 */
3408 if (wip) {
3409 error = xfs_dir_replace(tp, src_dp, src_name, wip->i_ino,
3410 spaceres);
3411 } else
3412 error = xfs_dir_removename(tp, src_dp, src_name, src_ip->i_ino,
3413 spaceres);
3414 if (error)
3415 goto out_trans_cancel;
3416
3417 xfs_trans_ichgtime(tp, src_dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
3418 xfs_trans_log_inode(tp, src_dp, XFS_ILOG_CORE);
3419 if (new_parent)
3420 xfs_trans_log_inode(tp, target_dp, XFS_ILOG_CORE);
3421
3422 error = xfs_finish_rename(tp);
3423 if (wip)
3424 xfs_irele(wip);
3425 return error;
3426
3427out_trans_cancel:
3428 xfs_trans_cancel(tp);
3429out_release_wip:
3430 if (wip)
3431 xfs_irele(wip);
3432 return error;
3433}
3434
3435static int
3436xfs_iflush(
3437 struct xfs_inode *ip,
3438 struct xfs_buf *bp)
3439{
3440 struct xfs_inode_log_item *iip = ip->i_itemp;
3441 struct xfs_dinode *dip;
3442 struct xfs_mount *mp = ip->i_mount;
3443 int error;
3444
3445 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
3446 ASSERT(xfs_isiflocked(ip));
3447 ASSERT(ip->i_df.if_format != XFS_DINODE_FMT_BTREE ||
3448 ip->i_df.if_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK));
3449 ASSERT(iip->ili_item.li_buf == bp);
3450
3451 dip = xfs_buf_offset(bp, ip->i_imap.im_boffset);
3452
3453 /*
3454 * We don't flush the inode if any of the following checks fail, but we
3455 * do still update the log item and attach to the backing buffer as if
3456 * the flush happened. This is a formality to facilitate predictable
3457 * error handling as the caller will shutdown and fail the buffer.
3458 */
3459 error = -EFSCORRUPTED;
3460 if (XFS_TEST_ERROR(dip->di_magic != cpu_to_be16(XFS_DINODE_MAGIC),
3461 mp, XFS_ERRTAG_IFLUSH_1)) {
3462 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3463 "%s: Bad inode %Lu magic number 0x%x, ptr "PTR_FMT,
3464 __func__, ip->i_ino, be16_to_cpu(dip->di_magic), dip);
3465 goto flush_out;
3466 }
3467 if (S_ISREG(VFS_I(ip)->i_mode)) {
3468 if (XFS_TEST_ERROR(
3469 ip->i_df.if_format != XFS_DINODE_FMT_EXTENTS &&
3470 ip->i_df.if_format != XFS_DINODE_FMT_BTREE,
3471 mp, XFS_ERRTAG_IFLUSH_3)) {
3472 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3473 "%s: Bad regular inode %Lu, ptr "PTR_FMT,
3474 __func__, ip->i_ino, ip);
3475 goto flush_out;
3476 }
3477 } else if (S_ISDIR(VFS_I(ip)->i_mode)) {
3478 if (XFS_TEST_ERROR(
3479 ip->i_df.if_format != XFS_DINODE_FMT_EXTENTS &&
3480 ip->i_df.if_format != XFS_DINODE_FMT_BTREE &&
3481 ip->i_df.if_format != XFS_DINODE_FMT_LOCAL,
3482 mp, XFS_ERRTAG_IFLUSH_4)) {
3483 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3484 "%s: Bad directory inode %Lu, ptr "PTR_FMT,
3485 __func__, ip->i_ino, ip);
3486 goto flush_out;
3487 }
3488 }
3489 if (XFS_TEST_ERROR(ip->i_df.if_nextents + xfs_ifork_nextents(ip->i_afp) >
3490 ip->i_d.di_nblocks, mp, XFS_ERRTAG_IFLUSH_5)) {
3491 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3492 "%s: detected corrupt incore inode %Lu, "
3493 "total extents = %d, nblocks = %Ld, ptr "PTR_FMT,
3494 __func__, ip->i_ino,
3495 ip->i_df.if_nextents + xfs_ifork_nextents(ip->i_afp),
3496 ip->i_d.di_nblocks, ip);
3497 goto flush_out;
3498 }
3499 if (XFS_TEST_ERROR(ip->i_d.di_forkoff > mp->m_sb.sb_inodesize,
3500 mp, XFS_ERRTAG_IFLUSH_6)) {
3501 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3502 "%s: bad inode %Lu, forkoff 0x%x, ptr "PTR_FMT,
3503 __func__, ip->i_ino, ip->i_d.di_forkoff, ip);
3504 goto flush_out;
3505 }
3506
3507 /*
3508 * Inode item log recovery for v2 inodes are dependent on the
3509 * di_flushiter count for correct sequencing. We bump the flush
3510 * iteration count so we can detect flushes which postdate a log record
3511 * during recovery. This is redundant as we now log every change and
3512 * hence this can't happen but we need to still do it to ensure
3513 * backwards compatibility with old kernels that predate logging all
3514 * inode changes.
3515 */
3516 if (!xfs_sb_version_has_v3inode(&mp->m_sb))
3517 ip->i_d.di_flushiter++;
3518
3519 /*
3520 * If there are inline format data / attr forks attached to this inode,
3521 * make sure they are not corrupt.
3522 */
3523 if (ip->i_df.if_format == XFS_DINODE_FMT_LOCAL &&
3524 xfs_ifork_verify_local_data(ip))
3525 goto flush_out;
3526 if (ip->i_afp && ip->i_afp->if_format == XFS_DINODE_FMT_LOCAL &&
3527 xfs_ifork_verify_local_attr(ip))
3528 goto flush_out;
3529
3530 /*
3531 * Copy the dirty parts of the inode into the on-disk inode. We always
3532 * copy out the core of the inode, because if the inode is dirty at all
3533 * the core must be.
3534 */
3535 xfs_inode_to_disk(ip, dip, iip->ili_item.li_lsn);
3536
3537 /* Wrap, we never let the log put out DI_MAX_FLUSH */
3538 if (ip->i_d.di_flushiter == DI_MAX_FLUSH)
3539 ip->i_d.di_flushiter = 0;
3540
3541 xfs_iflush_fork(ip, dip, iip, XFS_DATA_FORK);
3542 if (XFS_IFORK_Q(ip))
3543 xfs_iflush_fork(ip, dip, iip, XFS_ATTR_FORK);
3544
3545 /*
3546 * We've recorded everything logged in the inode, so we'd like to clear
3547 * the ili_fields bits so we don't log and flush things unnecessarily.
3548 * However, we can't stop logging all this information until the data
3549 * we've copied into the disk buffer is written to disk. If we did we
3550 * might overwrite the copy of the inode in the log with all the data
3551 * after re-logging only part of it, and in the face of a crash we
3552 * wouldn't have all the data we need to recover.
3553 *
3554 * What we do is move the bits to the ili_last_fields field. When
3555 * logging the inode, these bits are moved back to the ili_fields field.
3556 * In the xfs_iflush_done() routine we clear ili_last_fields, since we
3557 * know that the information those bits represent is permanently on
3558 * disk. As long as the flush completes before the inode is logged
3559 * again, then both ili_fields and ili_last_fields will be cleared.
3560 */
3561 error = 0;
3562flush_out:
3563 spin_lock(&iip->ili_lock);
3564 iip->ili_last_fields = iip->ili_fields;
3565 iip->ili_fields = 0;
3566 iip->ili_fsync_fields = 0;
3567 spin_unlock(&iip->ili_lock);
3568
3569 /*
3570 * Store the current LSN of the inode so that we can tell whether the
3571 * item has moved in the AIL from xfs_iflush_done().
3572 */
3573 xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn,
3574 &iip->ili_item.li_lsn);
3575
3576 /* generate the checksum. */
3577 xfs_dinode_calc_crc(mp, dip);
3578 return error;
3579}
3580
3581/*
3582 * Non-blocking flush of dirty inode metadata into the backing buffer.
3583 *
3584 * The caller must have a reference to the inode and hold the cluster buffer
3585 * locked. The function will walk across all the inodes on the cluster buffer it
3586 * can find and lock without blocking, and flush them to the cluster buffer.
3587 *
3588 * On successful flushing of at least one inode, the caller must write out the
3589 * buffer and release it. If no inodes are flushed, -EAGAIN will be returned and
3590 * the caller needs to release the buffer. On failure, the filesystem will be
3591 * shut down, the buffer will have been unlocked and released, and EFSCORRUPTED
3592 * will be returned.
3593 */
3594int
3595xfs_iflush_cluster(
3596 struct xfs_buf *bp)
3597{
3598 struct xfs_mount *mp = bp->b_mount;
3599 struct xfs_log_item *lip, *n;
3600 struct xfs_inode *ip;
3601 struct xfs_inode_log_item *iip;
3602 int clcount = 0;
3603 int error = 0;
3604
3605 /*
3606 * We must use the safe variant here as on shutdown xfs_iflush_abort()
3607 * can remove itself from the list.
3608 */
3609 list_for_each_entry_safe(lip, n, &bp->b_li_list, li_bio_list) {
3610 iip = (struct xfs_inode_log_item *)lip;
3611 ip = iip->ili_inode;
3612
3613 /*
3614 * Quick and dirty check to avoid locks if possible.
3615 */
3616 if (__xfs_iflags_test(ip, XFS_IRECLAIM | XFS_IFLOCK))
3617 continue;
3618 if (xfs_ipincount(ip))
3619 continue;
3620
3621 /*
3622 * The inode is still attached to the buffer, which means it is
3623 * dirty but reclaim might try to grab it. Check carefully for
3624 * that, and grab the ilock while still holding the i_flags_lock
3625 * to guarantee reclaim will not be able to reclaim this inode
3626 * once we drop the i_flags_lock.
3627 */
3628 spin_lock(&ip->i_flags_lock);
3629 ASSERT(!__xfs_iflags_test(ip, XFS_ISTALE));
3630 if (__xfs_iflags_test(ip, XFS_IRECLAIM | XFS_IFLOCK)) {
3631 spin_unlock(&ip->i_flags_lock);
3632 continue;
3633 }
3634
3635 /*
3636 * ILOCK will pin the inode against reclaim and prevent
3637 * concurrent transactions modifying the inode while we are
3638 * flushing the inode.
3639 */
3640 if (!xfs_ilock_nowait(ip, XFS_ILOCK_SHARED)) {
3641 spin_unlock(&ip->i_flags_lock);
3642 continue;
3643 }
3644 spin_unlock(&ip->i_flags_lock);
3645
3646 /*
3647 * Skip inodes that are already flush locked as they have
3648 * already been written to the buffer.
3649 */
3650 if (!xfs_iflock_nowait(ip)) {
3651 xfs_iunlock(ip, XFS_ILOCK_SHARED);
3652 continue;
3653 }
3654
3655 /*
3656 * Abort flushing this inode if we are shut down because the
3657 * inode may not currently be in the AIL. This can occur when
3658 * log I/O failure unpins the inode without inserting into the
3659 * AIL, leaving a dirty/unpinned inode attached to the buffer
3660 * that otherwise looks like it should be flushed.
3661 */
3662 if (XFS_FORCED_SHUTDOWN(mp)) {
3663 xfs_iunpin_wait(ip);
3664 /* xfs_iflush_abort() drops the flush lock */
3665 xfs_iflush_abort(ip);
3666 xfs_iunlock(ip, XFS_ILOCK_SHARED);
3667 error = -EIO;
3668 continue;
3669 }
3670
3671 /* don't block waiting on a log force to unpin dirty inodes */
3672 if (xfs_ipincount(ip)) {
3673 xfs_ifunlock(ip);
3674 xfs_iunlock(ip, XFS_ILOCK_SHARED);
3675 continue;
3676 }
3677
3678 if (!xfs_inode_clean(ip))
3679 error = xfs_iflush(ip, bp);
3680 else
3681 xfs_ifunlock(ip);
3682 xfs_iunlock(ip, XFS_ILOCK_SHARED);
3683 if (error)
3684 break;
3685 clcount++;
3686 }
3687
3688 if (error) {
3689 bp->b_flags |= XBF_ASYNC;
3690 xfs_buf_ioend_fail(bp);
3691 xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
3692 return error;
3693 }
3694
3695 if (!clcount)
3696 return -EAGAIN;
3697
3698 XFS_STATS_INC(mp, xs_icluster_flushcnt);
3699 XFS_STATS_ADD(mp, xs_icluster_flushinode, clcount);
3700 return 0;
3701
3702}
3703
3704/* Release an inode. */
3705void
3706xfs_irele(
3707 struct xfs_inode *ip)
3708{
3709 trace_xfs_irele(ip, _RET_IP_);
3710 iput(VFS_I(ip));
3711}
3712
3713/*
3714 * Ensure all commited transactions touching the inode are written to the log.
3715 */
3716int
3717xfs_log_force_inode(
3718 struct xfs_inode *ip)
3719{
3720 xfs_lsn_t lsn = 0;
3721
3722 xfs_ilock(ip, XFS_ILOCK_SHARED);
3723 if (xfs_ipincount(ip))
3724 lsn = ip->i_itemp->ili_last_lsn;
3725 xfs_iunlock(ip, XFS_ILOCK_SHARED);
3726
3727 if (!lsn)
3728 return 0;
3729 return xfs_log_force_lsn(ip->i_mount, lsn, XFS_LOG_SYNC, NULL);
3730}
3731
3732/*
3733 * Grab the exclusive iolock for a data copy from src to dest, making sure to
3734 * abide vfs locking order (lowest pointer value goes first) and breaking the
3735 * layout leases before proceeding. The loop is needed because we cannot call
3736 * the blocking break_layout() with the iolocks held, and therefore have to
3737 * back out both locks.
3738 */
3739static int
3740xfs_iolock_two_inodes_and_break_layout(
3741 struct inode *src,
3742 struct inode *dest)
3743{
3744 int error;
3745
3746 if (src > dest)
3747 swap(src, dest);
3748
3749retry:
3750 /* Wait to break both inodes' layouts before we start locking. */
3751 error = break_layout(src, true);
3752 if (error)
3753 return error;
3754 if (src != dest) {
3755 error = break_layout(dest, true);
3756 if (error)
3757 return error;
3758 }
3759
3760 /* Lock one inode and make sure nobody got in and leased it. */
3761 inode_lock(src);
3762 error = break_layout(src, false);
3763 if (error) {
3764 inode_unlock(src);
3765 if (error == -EWOULDBLOCK)
3766 goto retry;
3767 return error;
3768 }
3769
3770 if (src == dest)
3771 return 0;
3772
3773 /* Lock the other inode and make sure nobody got in and leased it. */
3774 inode_lock_nested(dest, I_MUTEX_NONDIR2);
3775 error = break_layout(dest, false);
3776 if (error) {
3777 inode_unlock(src);
3778 inode_unlock(dest);
3779 if (error == -EWOULDBLOCK)
3780 goto retry;
3781 return error;
3782 }
3783
3784 return 0;
3785}
3786
3787/*
3788 * Lock two inodes so that userspace cannot initiate I/O via file syscalls or
3789 * mmap activity.
3790 */
3791int
3792xfs_ilock2_io_mmap(
3793 struct xfs_inode *ip1,
3794 struct xfs_inode *ip2)
3795{
3796 int ret;
3797
3798 ret = xfs_iolock_two_inodes_and_break_layout(VFS_I(ip1), VFS_I(ip2));
3799 if (ret)
3800 return ret;
3801 if (ip1 == ip2)
3802 xfs_ilock(ip1, XFS_MMAPLOCK_EXCL);
3803 else
3804 xfs_lock_two_inodes(ip1, XFS_MMAPLOCK_EXCL,
3805 ip2, XFS_MMAPLOCK_EXCL);
3806 return 0;
3807}
3808
3809/* Unlock both inodes to allow IO and mmap activity. */
3810void
3811xfs_iunlock2_io_mmap(
3812 struct xfs_inode *ip1,
3813 struct xfs_inode *ip2)
3814{
3815 bool same_inode = (ip1 == ip2);
3816
3817 xfs_iunlock(ip2, XFS_MMAPLOCK_EXCL);
3818 if (!same_inode)
3819 xfs_iunlock(ip1, XFS_MMAPLOCK_EXCL);
3820 inode_unlock(VFS_I(ip2));
3821 if (!same_inode)
3822 inode_unlock(VFS_I(ip1));
3823}
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
20#include "xfs.h"
21#include "xfs_fs.h"
22#include "xfs_shared.h"
23#include "xfs_format.h"
24#include "xfs_log_format.h"
25#include "xfs_trans_resv.h"
26#include "xfs_inum.h"
27#include "xfs_sb.h"
28#include "xfs_ag.h"
29#include "xfs_mount.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_error.h"
44#include "xfs_quota.h"
45#include "xfs_filestream.h"
46#include "xfs_cksum.h"
47#include "xfs_trace.h"
48#include "xfs_icache.h"
49#include "xfs_symlink.h"
50#include "xfs_trans_priv.h"
51#include "xfs_log.h"
52#include "xfs_bmap_btree.h"
53
54kmem_zone_t *xfs_inode_zone;
55
56/*
57 * Used in xfs_itruncate_extents(). This is the maximum number of extents
58 * freed from a file in a single transaction.
59 */
60#define XFS_ITRUNC_MAX_EXTENTS 2
61
62STATIC int xfs_iflush_int(xfs_inode_t *, xfs_buf_t *);
63
64STATIC int xfs_iunlink_remove(xfs_trans_t *, xfs_inode_t *);
65
66/*
67 * helper function to extract extent size hint from inode
68 */
69xfs_extlen_t
70xfs_get_extsz_hint(
71 struct xfs_inode *ip)
72{
73 if ((ip->i_d.di_flags & XFS_DIFLAG_EXTSIZE) && ip->i_d.di_extsize)
74 return ip->i_d.di_extsize;
75 if (XFS_IS_REALTIME_INODE(ip))
76 return ip->i_mount->m_sb.sb_rextsize;
77 return 0;
78}
79
80/*
81 * These two are wrapper routines around the xfs_ilock() routine used to
82 * centralize some grungy code. They are used in places that wish to lock the
83 * inode solely for reading the extents. The reason these places can't just
84 * call xfs_ilock(ip, XFS_ILOCK_SHARED) is that the inode lock also guards to
85 * bringing in of the extents from disk for a file in b-tree format. If the
86 * inode is in b-tree format, then we need to lock the inode exclusively until
87 * the extents are read in. Locking it exclusively all the time would limit
88 * our parallelism unnecessarily, though. What we do instead is check to see
89 * if the extents have been read in yet, and only lock the inode exclusively
90 * if they have not.
91 *
92 * The functions return a value which should be given to the corresponding
93 * xfs_iunlock() call.
94 */
95uint
96xfs_ilock_data_map_shared(
97 struct xfs_inode *ip)
98{
99 uint lock_mode = XFS_ILOCK_SHARED;
100
101 if (ip->i_d.di_format == XFS_DINODE_FMT_BTREE &&
102 (ip->i_df.if_flags & XFS_IFEXTENTS) == 0)
103 lock_mode = XFS_ILOCK_EXCL;
104 xfs_ilock(ip, lock_mode);
105 return lock_mode;
106}
107
108uint
109xfs_ilock_attr_map_shared(
110 struct xfs_inode *ip)
111{
112 uint lock_mode = XFS_ILOCK_SHARED;
113
114 if (ip->i_d.di_aformat == XFS_DINODE_FMT_BTREE &&
115 (ip->i_afp->if_flags & XFS_IFEXTENTS) == 0)
116 lock_mode = XFS_ILOCK_EXCL;
117 xfs_ilock(ip, lock_mode);
118 return lock_mode;
119}
120
121/*
122 * The xfs inode contains 2 locks: a multi-reader lock called the
123 * i_iolock and a multi-reader lock called the i_lock. This routine
124 * allows either or both of the locks to be obtained.
125 *
126 * The 2 locks should always be ordered so that the IO lock is
127 * obtained first in order to prevent deadlock.
128 *
129 * ip -- the inode being locked
130 * lock_flags -- this parameter indicates the inode's locks
131 * to be locked. It can be:
132 * XFS_IOLOCK_SHARED,
133 * XFS_IOLOCK_EXCL,
134 * XFS_ILOCK_SHARED,
135 * XFS_ILOCK_EXCL,
136 * XFS_IOLOCK_SHARED | XFS_ILOCK_SHARED,
137 * XFS_IOLOCK_SHARED | XFS_ILOCK_EXCL,
138 * XFS_IOLOCK_EXCL | XFS_ILOCK_SHARED,
139 * XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL
140 */
141void
142xfs_ilock(
143 xfs_inode_t *ip,
144 uint lock_flags)
145{
146 trace_xfs_ilock(ip, lock_flags, _RET_IP_);
147
148 /*
149 * You can't set both SHARED and EXCL for the same lock,
150 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
151 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
152 */
153 ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
154 (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
155 ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
156 (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
157 ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_DEP_MASK)) == 0);
158
159 if (lock_flags & XFS_IOLOCK_EXCL)
160 mrupdate_nested(&ip->i_iolock, XFS_IOLOCK_DEP(lock_flags));
161 else if (lock_flags & XFS_IOLOCK_SHARED)
162 mraccess_nested(&ip->i_iolock, XFS_IOLOCK_DEP(lock_flags));
163
164 if (lock_flags & XFS_ILOCK_EXCL)
165 mrupdate_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
166 else if (lock_flags & XFS_ILOCK_SHARED)
167 mraccess_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
168}
169
170/*
171 * This is just like xfs_ilock(), except that the caller
172 * is guaranteed not to sleep. It returns 1 if it gets
173 * the requested locks and 0 otherwise. If the IO lock is
174 * obtained but the inode lock cannot be, then the IO lock
175 * is dropped before returning.
176 *
177 * ip -- the inode being locked
178 * lock_flags -- this parameter indicates the inode's locks to be
179 * to be locked. See the comment for xfs_ilock() for a list
180 * of valid values.
181 */
182int
183xfs_ilock_nowait(
184 xfs_inode_t *ip,
185 uint lock_flags)
186{
187 trace_xfs_ilock_nowait(ip, lock_flags, _RET_IP_);
188
189 /*
190 * You can't set both SHARED and EXCL for the same lock,
191 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
192 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
193 */
194 ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
195 (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
196 ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
197 (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
198 ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_DEP_MASK)) == 0);
199
200 if (lock_flags & XFS_IOLOCK_EXCL) {
201 if (!mrtryupdate(&ip->i_iolock))
202 goto out;
203 } else if (lock_flags & XFS_IOLOCK_SHARED) {
204 if (!mrtryaccess(&ip->i_iolock))
205 goto out;
206 }
207 if (lock_flags & XFS_ILOCK_EXCL) {
208 if (!mrtryupdate(&ip->i_lock))
209 goto out_undo_iolock;
210 } else if (lock_flags & XFS_ILOCK_SHARED) {
211 if (!mrtryaccess(&ip->i_lock))
212 goto out_undo_iolock;
213 }
214 return 1;
215
216 out_undo_iolock:
217 if (lock_flags & XFS_IOLOCK_EXCL)
218 mrunlock_excl(&ip->i_iolock);
219 else if (lock_flags & XFS_IOLOCK_SHARED)
220 mrunlock_shared(&ip->i_iolock);
221 out:
222 return 0;
223}
224
225/*
226 * xfs_iunlock() is used to drop the inode locks acquired with
227 * xfs_ilock() and xfs_ilock_nowait(). The caller must pass
228 * in the flags given to xfs_ilock() or xfs_ilock_nowait() so
229 * that we know which locks to drop.
230 *
231 * ip -- the inode being unlocked
232 * lock_flags -- this parameter indicates the inode's locks to be
233 * to be unlocked. See the comment for xfs_ilock() for a list
234 * of valid values for this parameter.
235 *
236 */
237void
238xfs_iunlock(
239 xfs_inode_t *ip,
240 uint lock_flags)
241{
242 /*
243 * You can't set both SHARED and EXCL for the same lock,
244 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
245 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
246 */
247 ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
248 (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
249 ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
250 (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
251 ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_DEP_MASK)) == 0);
252 ASSERT(lock_flags != 0);
253
254 if (lock_flags & XFS_IOLOCK_EXCL)
255 mrunlock_excl(&ip->i_iolock);
256 else if (lock_flags & XFS_IOLOCK_SHARED)
257 mrunlock_shared(&ip->i_iolock);
258
259 if (lock_flags & XFS_ILOCK_EXCL)
260 mrunlock_excl(&ip->i_lock);
261 else if (lock_flags & XFS_ILOCK_SHARED)
262 mrunlock_shared(&ip->i_lock);
263
264 trace_xfs_iunlock(ip, lock_flags, _RET_IP_);
265}
266
267/*
268 * give up write locks. the i/o lock cannot be held nested
269 * if it is being demoted.
270 */
271void
272xfs_ilock_demote(
273 xfs_inode_t *ip,
274 uint lock_flags)
275{
276 ASSERT(lock_flags & (XFS_IOLOCK_EXCL|XFS_ILOCK_EXCL));
277 ASSERT((lock_flags & ~(XFS_IOLOCK_EXCL|XFS_ILOCK_EXCL)) == 0);
278
279 if (lock_flags & XFS_ILOCK_EXCL)
280 mrdemote(&ip->i_lock);
281 if (lock_flags & XFS_IOLOCK_EXCL)
282 mrdemote(&ip->i_iolock);
283
284 trace_xfs_ilock_demote(ip, lock_flags, _RET_IP_);
285}
286
287#if defined(DEBUG) || defined(XFS_WARN)
288int
289xfs_isilocked(
290 xfs_inode_t *ip,
291 uint lock_flags)
292{
293 if (lock_flags & (XFS_ILOCK_EXCL|XFS_ILOCK_SHARED)) {
294 if (!(lock_flags & XFS_ILOCK_SHARED))
295 return !!ip->i_lock.mr_writer;
296 return rwsem_is_locked(&ip->i_lock.mr_lock);
297 }
298
299 if (lock_flags & (XFS_IOLOCK_EXCL|XFS_IOLOCK_SHARED)) {
300 if (!(lock_flags & XFS_IOLOCK_SHARED))
301 return !!ip->i_iolock.mr_writer;
302 return rwsem_is_locked(&ip->i_iolock.mr_lock);
303 }
304
305 ASSERT(0);
306 return 0;
307}
308#endif
309
310#ifdef DEBUG
311int xfs_locked_n;
312int xfs_small_retries;
313int xfs_middle_retries;
314int xfs_lots_retries;
315int xfs_lock_delays;
316#endif
317
318/*
319 * Bump the subclass so xfs_lock_inodes() acquires each lock with
320 * a different value
321 */
322static inline int
323xfs_lock_inumorder(int lock_mode, int subclass)
324{
325 if (lock_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL))
326 lock_mode |= (subclass + XFS_LOCK_INUMORDER) << XFS_IOLOCK_SHIFT;
327 if (lock_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL))
328 lock_mode |= (subclass + XFS_LOCK_INUMORDER) << XFS_ILOCK_SHIFT;
329
330 return lock_mode;
331}
332
333/*
334 * The following routine will lock n inodes in exclusive mode.
335 * We assume the caller calls us with the inodes in i_ino order.
336 *
337 * We need to detect deadlock where an inode that we lock
338 * is in the AIL and we start waiting for another inode that is locked
339 * by a thread in a long running transaction (such as truncate). This can
340 * result in deadlock since the long running trans might need to wait
341 * for the inode we just locked in order to push the tail and free space
342 * in the log.
343 */
344void
345xfs_lock_inodes(
346 xfs_inode_t **ips,
347 int inodes,
348 uint lock_mode)
349{
350 int attempts = 0, i, j, try_lock;
351 xfs_log_item_t *lp;
352
353 ASSERT(ips && (inodes >= 2)); /* we need at least two */
354
355 try_lock = 0;
356 i = 0;
357
358again:
359 for (; i < inodes; i++) {
360 ASSERT(ips[i]);
361
362 if (i && (ips[i] == ips[i-1])) /* Already locked */
363 continue;
364
365 /*
366 * If try_lock is not set yet, make sure all locked inodes
367 * are not in the AIL.
368 * If any are, set try_lock to be used later.
369 */
370
371 if (!try_lock) {
372 for (j = (i - 1); j >= 0 && !try_lock; j--) {
373 lp = (xfs_log_item_t *)ips[j]->i_itemp;
374 if (lp && (lp->li_flags & XFS_LI_IN_AIL)) {
375 try_lock++;
376 }
377 }
378 }
379
380 /*
381 * If any of the previous locks we have locked is in the AIL,
382 * we must TRY to get the second and subsequent locks. If
383 * we can't get any, we must release all we have
384 * and try again.
385 */
386
387 if (try_lock) {
388 /* try_lock must be 0 if i is 0. */
389 /*
390 * try_lock means we have an inode locked
391 * that is in the AIL.
392 */
393 ASSERT(i != 0);
394 if (!xfs_ilock_nowait(ips[i], xfs_lock_inumorder(lock_mode, i))) {
395 attempts++;
396
397 /*
398 * Unlock all previous guys and try again.
399 * xfs_iunlock will try to push the tail
400 * if the inode is in the AIL.
401 */
402
403 for(j = i - 1; j >= 0; j--) {
404
405 /*
406 * Check to see if we've already
407 * unlocked this one.
408 * Not the first one going back,
409 * and the inode ptr is the same.
410 */
411 if ((j != (i - 1)) && ips[j] ==
412 ips[j+1])
413 continue;
414
415 xfs_iunlock(ips[j], lock_mode);
416 }
417
418 if ((attempts % 5) == 0) {
419 delay(1); /* Don't just spin the CPU */
420#ifdef DEBUG
421 xfs_lock_delays++;
422#endif
423 }
424 i = 0;
425 try_lock = 0;
426 goto again;
427 }
428 } else {
429 xfs_ilock(ips[i], xfs_lock_inumorder(lock_mode, i));
430 }
431 }
432
433#ifdef DEBUG
434 if (attempts) {
435 if (attempts < 5) xfs_small_retries++;
436 else if (attempts < 100) xfs_middle_retries++;
437 else xfs_lots_retries++;
438 } else {
439 xfs_locked_n++;
440 }
441#endif
442}
443
444/*
445 * xfs_lock_two_inodes() can only be used to lock one type of lock
446 * at a time - the iolock or the ilock, but not both at once. If
447 * we lock both at once, lockdep will report false positives saying
448 * we have violated locking orders.
449 */
450void
451xfs_lock_two_inodes(
452 xfs_inode_t *ip0,
453 xfs_inode_t *ip1,
454 uint lock_mode)
455{
456 xfs_inode_t *temp;
457 int attempts = 0;
458 xfs_log_item_t *lp;
459
460 if (lock_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL))
461 ASSERT((lock_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)) == 0);
462 ASSERT(ip0->i_ino != ip1->i_ino);
463
464 if (ip0->i_ino > ip1->i_ino) {
465 temp = ip0;
466 ip0 = ip1;
467 ip1 = temp;
468 }
469
470 again:
471 xfs_ilock(ip0, xfs_lock_inumorder(lock_mode, 0));
472
473 /*
474 * If the first lock we have locked is in the AIL, we must TRY to get
475 * the second lock. If we can't get it, we must release the first one
476 * and try again.
477 */
478 lp = (xfs_log_item_t *)ip0->i_itemp;
479 if (lp && (lp->li_flags & XFS_LI_IN_AIL)) {
480 if (!xfs_ilock_nowait(ip1, xfs_lock_inumorder(lock_mode, 1))) {
481 xfs_iunlock(ip0, lock_mode);
482 if ((++attempts % 5) == 0)
483 delay(1); /* Don't just spin the CPU */
484 goto again;
485 }
486 } else {
487 xfs_ilock(ip1, xfs_lock_inumorder(lock_mode, 1));
488 }
489}
490
491
492void
493__xfs_iflock(
494 struct xfs_inode *ip)
495{
496 wait_queue_head_t *wq = bit_waitqueue(&ip->i_flags, __XFS_IFLOCK_BIT);
497 DEFINE_WAIT_BIT(wait, &ip->i_flags, __XFS_IFLOCK_BIT);
498
499 do {
500 prepare_to_wait_exclusive(wq, &wait.wait, TASK_UNINTERRUPTIBLE);
501 if (xfs_isiflocked(ip))
502 io_schedule();
503 } while (!xfs_iflock_nowait(ip));
504
505 finish_wait(wq, &wait.wait);
506}
507
508STATIC uint
509_xfs_dic2xflags(
510 __uint16_t di_flags)
511{
512 uint flags = 0;
513
514 if (di_flags & XFS_DIFLAG_ANY) {
515 if (di_flags & XFS_DIFLAG_REALTIME)
516 flags |= XFS_XFLAG_REALTIME;
517 if (di_flags & XFS_DIFLAG_PREALLOC)
518 flags |= XFS_XFLAG_PREALLOC;
519 if (di_flags & XFS_DIFLAG_IMMUTABLE)
520 flags |= XFS_XFLAG_IMMUTABLE;
521 if (di_flags & XFS_DIFLAG_APPEND)
522 flags |= XFS_XFLAG_APPEND;
523 if (di_flags & XFS_DIFLAG_SYNC)
524 flags |= XFS_XFLAG_SYNC;
525 if (di_flags & XFS_DIFLAG_NOATIME)
526 flags |= XFS_XFLAG_NOATIME;
527 if (di_flags & XFS_DIFLAG_NODUMP)
528 flags |= XFS_XFLAG_NODUMP;
529 if (di_flags & XFS_DIFLAG_RTINHERIT)
530 flags |= XFS_XFLAG_RTINHERIT;
531 if (di_flags & XFS_DIFLAG_PROJINHERIT)
532 flags |= XFS_XFLAG_PROJINHERIT;
533 if (di_flags & XFS_DIFLAG_NOSYMLINKS)
534 flags |= XFS_XFLAG_NOSYMLINKS;
535 if (di_flags & XFS_DIFLAG_EXTSIZE)
536 flags |= XFS_XFLAG_EXTSIZE;
537 if (di_flags & XFS_DIFLAG_EXTSZINHERIT)
538 flags |= XFS_XFLAG_EXTSZINHERIT;
539 if (di_flags & XFS_DIFLAG_NODEFRAG)
540 flags |= XFS_XFLAG_NODEFRAG;
541 if (di_flags & XFS_DIFLAG_FILESTREAM)
542 flags |= XFS_XFLAG_FILESTREAM;
543 }
544
545 return flags;
546}
547
548uint
549xfs_ip2xflags(
550 xfs_inode_t *ip)
551{
552 xfs_icdinode_t *dic = &ip->i_d;
553
554 return _xfs_dic2xflags(dic->di_flags) |
555 (XFS_IFORK_Q(ip) ? XFS_XFLAG_HASATTR : 0);
556}
557
558uint
559xfs_dic2xflags(
560 xfs_dinode_t *dip)
561{
562 return _xfs_dic2xflags(be16_to_cpu(dip->di_flags)) |
563 (XFS_DFORK_Q(dip) ? XFS_XFLAG_HASATTR : 0);
564}
565
566/*
567 * Lookups up an inode from "name". If ci_name is not NULL, then a CI match
568 * is allowed, otherwise it has to be an exact match. If a CI match is found,
569 * ci_name->name will point to a the actual name (caller must free) or
570 * will be set to NULL if an exact match is found.
571 */
572int
573xfs_lookup(
574 xfs_inode_t *dp,
575 struct xfs_name *name,
576 xfs_inode_t **ipp,
577 struct xfs_name *ci_name)
578{
579 xfs_ino_t inum;
580 int error;
581 uint lock_mode;
582
583 trace_xfs_lookup(dp, name);
584
585 if (XFS_FORCED_SHUTDOWN(dp->i_mount))
586 return XFS_ERROR(EIO);
587
588 lock_mode = xfs_ilock_data_map_shared(dp);
589 error = xfs_dir_lookup(NULL, dp, name, &inum, ci_name);
590 xfs_iunlock(dp, lock_mode);
591
592 if (error)
593 goto out;
594
595 error = xfs_iget(dp->i_mount, NULL, inum, 0, 0, ipp);
596 if (error)
597 goto out_free_name;
598
599 return 0;
600
601out_free_name:
602 if (ci_name)
603 kmem_free(ci_name->name);
604out:
605 *ipp = NULL;
606 return error;
607}
608
609/*
610 * Allocate an inode on disk and return a copy of its in-core version.
611 * The in-core inode is locked exclusively. Set mode, nlink, and rdev
612 * appropriately within the inode. The uid and gid for the inode are
613 * set according to the contents of the given cred structure.
614 *
615 * Use xfs_dialloc() to allocate the on-disk inode. If xfs_dialloc()
616 * has a free inode available, call xfs_iget() to obtain the in-core
617 * version of the allocated inode. Finally, fill in the inode and
618 * log its initial contents. In this case, ialloc_context would be
619 * set to NULL.
620 *
621 * If xfs_dialloc() does not have an available inode, it will replenish
622 * its supply by doing an allocation. Since we can only do one
623 * allocation within a transaction without deadlocks, we must commit
624 * the current transaction before returning the inode itself.
625 * In this case, therefore, we will set ialloc_context and return.
626 * The caller should then commit the current transaction, start a new
627 * transaction, and call xfs_ialloc() again to actually get the inode.
628 *
629 * To ensure that some other process does not grab the inode that
630 * was allocated during the first call to xfs_ialloc(), this routine
631 * also returns the [locked] bp pointing to the head of the freelist
632 * as ialloc_context. The caller should hold this buffer across
633 * the commit and pass it back into this routine on the second call.
634 *
635 * If we are allocating quota inodes, we do not have a parent inode
636 * to attach to or associate with (i.e. pip == NULL) because they
637 * are not linked into the directory structure - they are attached
638 * directly to the superblock - and so have no parent.
639 */
640int
641xfs_ialloc(
642 xfs_trans_t *tp,
643 xfs_inode_t *pip,
644 umode_t mode,
645 xfs_nlink_t nlink,
646 xfs_dev_t rdev,
647 prid_t prid,
648 int okalloc,
649 xfs_buf_t **ialloc_context,
650 xfs_inode_t **ipp)
651{
652 struct xfs_mount *mp = tp->t_mountp;
653 xfs_ino_t ino;
654 xfs_inode_t *ip;
655 uint flags;
656 int error;
657 timespec_t tv;
658 int filestreams = 0;
659
660 /*
661 * Call the space management code to pick
662 * the on-disk inode to be allocated.
663 */
664 error = xfs_dialloc(tp, pip ? pip->i_ino : 0, mode, okalloc,
665 ialloc_context, &ino);
666 if (error)
667 return error;
668 if (*ialloc_context || ino == NULLFSINO) {
669 *ipp = NULL;
670 return 0;
671 }
672 ASSERT(*ialloc_context == NULL);
673
674 /*
675 * Get the in-core inode with the lock held exclusively.
676 * This is because we're setting fields here we need
677 * to prevent others from looking at until we're done.
678 */
679 error = xfs_iget(mp, tp, ino, XFS_IGET_CREATE,
680 XFS_ILOCK_EXCL, &ip);
681 if (error)
682 return error;
683 ASSERT(ip != NULL);
684
685 ip->i_d.di_mode = mode;
686 ip->i_d.di_onlink = 0;
687 ip->i_d.di_nlink = nlink;
688 ASSERT(ip->i_d.di_nlink == nlink);
689 ip->i_d.di_uid = xfs_kuid_to_uid(current_fsuid());
690 ip->i_d.di_gid = xfs_kgid_to_gid(current_fsgid());
691 xfs_set_projid(ip, prid);
692 memset(&(ip->i_d.di_pad[0]), 0, sizeof(ip->i_d.di_pad));
693
694 /*
695 * If the superblock version is up to where we support new format
696 * inodes and this is currently an old format inode, then change
697 * the inode version number now. This way we only do the conversion
698 * here rather than here and in the flush/logging code.
699 */
700 if (xfs_sb_version_hasnlink(&mp->m_sb) &&
701 ip->i_d.di_version == 1) {
702 ip->i_d.di_version = 2;
703 /*
704 * We've already zeroed the old link count, the projid field,
705 * and the pad field.
706 */
707 }
708
709 /*
710 * Project ids won't be stored on disk if we are using a version 1 inode.
711 */
712 if ((prid != 0) && (ip->i_d.di_version == 1))
713 xfs_bump_ino_vers2(tp, ip);
714
715 if (pip && XFS_INHERIT_GID(pip)) {
716 ip->i_d.di_gid = pip->i_d.di_gid;
717 if ((pip->i_d.di_mode & S_ISGID) && S_ISDIR(mode)) {
718 ip->i_d.di_mode |= S_ISGID;
719 }
720 }
721
722 /*
723 * If the group ID of the new file does not match the effective group
724 * ID or one of the supplementary group IDs, the S_ISGID bit is cleared
725 * (and only if the irix_sgid_inherit compatibility variable is set).
726 */
727 if ((irix_sgid_inherit) &&
728 (ip->i_d.di_mode & S_ISGID) &&
729 (!in_group_p(xfs_gid_to_kgid(ip->i_d.di_gid)))) {
730 ip->i_d.di_mode &= ~S_ISGID;
731 }
732
733 ip->i_d.di_size = 0;
734 ip->i_d.di_nextents = 0;
735 ASSERT(ip->i_d.di_nblocks == 0);
736
737 nanotime(&tv);
738 ip->i_d.di_mtime.t_sec = (__int32_t)tv.tv_sec;
739 ip->i_d.di_mtime.t_nsec = (__int32_t)tv.tv_nsec;
740 ip->i_d.di_atime = ip->i_d.di_mtime;
741 ip->i_d.di_ctime = ip->i_d.di_mtime;
742
743 /*
744 * di_gen will have been taken care of in xfs_iread.
745 */
746 ip->i_d.di_extsize = 0;
747 ip->i_d.di_dmevmask = 0;
748 ip->i_d.di_dmstate = 0;
749 ip->i_d.di_flags = 0;
750
751 if (ip->i_d.di_version == 3) {
752 ASSERT(ip->i_d.di_ino == ino);
753 ASSERT(uuid_equal(&ip->i_d.di_uuid, &mp->m_sb.sb_uuid));
754 ip->i_d.di_crc = 0;
755 ip->i_d.di_changecount = 1;
756 ip->i_d.di_lsn = 0;
757 ip->i_d.di_flags2 = 0;
758 memset(&(ip->i_d.di_pad2[0]), 0, sizeof(ip->i_d.di_pad2));
759 ip->i_d.di_crtime = ip->i_d.di_mtime;
760 }
761
762
763 flags = XFS_ILOG_CORE;
764 switch (mode & S_IFMT) {
765 case S_IFIFO:
766 case S_IFCHR:
767 case S_IFBLK:
768 case S_IFSOCK:
769 ip->i_d.di_format = XFS_DINODE_FMT_DEV;
770 ip->i_df.if_u2.if_rdev = rdev;
771 ip->i_df.if_flags = 0;
772 flags |= XFS_ILOG_DEV;
773 break;
774 case S_IFREG:
775 /*
776 * we can't set up filestreams until after the VFS inode
777 * is set up properly.
778 */
779 if (pip && xfs_inode_is_filestream(pip))
780 filestreams = 1;
781 /* fall through */
782 case S_IFDIR:
783 if (pip && (pip->i_d.di_flags & XFS_DIFLAG_ANY)) {
784 uint di_flags = 0;
785
786 if (S_ISDIR(mode)) {
787 if (pip->i_d.di_flags & XFS_DIFLAG_RTINHERIT)
788 di_flags |= XFS_DIFLAG_RTINHERIT;
789 if (pip->i_d.di_flags & XFS_DIFLAG_EXTSZINHERIT) {
790 di_flags |= XFS_DIFLAG_EXTSZINHERIT;
791 ip->i_d.di_extsize = pip->i_d.di_extsize;
792 }
793 } else if (S_ISREG(mode)) {
794 if (pip->i_d.di_flags & XFS_DIFLAG_RTINHERIT)
795 di_flags |= XFS_DIFLAG_REALTIME;
796 if (pip->i_d.di_flags & XFS_DIFLAG_EXTSZINHERIT) {
797 di_flags |= XFS_DIFLAG_EXTSIZE;
798 ip->i_d.di_extsize = pip->i_d.di_extsize;
799 }
800 }
801 if ((pip->i_d.di_flags & XFS_DIFLAG_NOATIME) &&
802 xfs_inherit_noatime)
803 di_flags |= XFS_DIFLAG_NOATIME;
804 if ((pip->i_d.di_flags & XFS_DIFLAG_NODUMP) &&
805 xfs_inherit_nodump)
806 di_flags |= XFS_DIFLAG_NODUMP;
807 if ((pip->i_d.di_flags & XFS_DIFLAG_SYNC) &&
808 xfs_inherit_sync)
809 di_flags |= XFS_DIFLAG_SYNC;
810 if ((pip->i_d.di_flags & XFS_DIFLAG_NOSYMLINKS) &&
811 xfs_inherit_nosymlinks)
812 di_flags |= XFS_DIFLAG_NOSYMLINKS;
813 if (pip->i_d.di_flags & XFS_DIFLAG_PROJINHERIT)
814 di_flags |= XFS_DIFLAG_PROJINHERIT;
815 if ((pip->i_d.di_flags & XFS_DIFLAG_NODEFRAG) &&
816 xfs_inherit_nodefrag)
817 di_flags |= XFS_DIFLAG_NODEFRAG;
818 if (pip->i_d.di_flags & XFS_DIFLAG_FILESTREAM)
819 di_flags |= XFS_DIFLAG_FILESTREAM;
820 ip->i_d.di_flags |= di_flags;
821 }
822 /* FALLTHROUGH */
823 case S_IFLNK:
824 ip->i_d.di_format = XFS_DINODE_FMT_EXTENTS;
825 ip->i_df.if_flags = XFS_IFEXTENTS;
826 ip->i_df.if_bytes = ip->i_df.if_real_bytes = 0;
827 ip->i_df.if_u1.if_extents = NULL;
828 break;
829 default:
830 ASSERT(0);
831 }
832 /*
833 * Attribute fork settings for new inode.
834 */
835 ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;
836 ip->i_d.di_anextents = 0;
837
838 /*
839 * Log the new values stuffed into the inode.
840 */
841 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
842 xfs_trans_log_inode(tp, ip, flags);
843
844 /* now that we have an i_mode we can setup inode ops and unlock */
845 xfs_setup_inode(ip);
846
847 /* now we have set up the vfs inode we can associate the filestream */
848 if (filestreams) {
849 error = xfs_filestream_associate(pip, ip);
850 if (error < 0)
851 return -error;
852 if (!error)
853 xfs_iflags_set(ip, XFS_IFILESTREAM);
854 }
855
856 *ipp = ip;
857 return 0;
858}
859
860/*
861 * Allocates a new inode from disk and return a pointer to the
862 * incore copy. This routine will internally commit the current
863 * transaction and allocate a new one if the Space Manager needed
864 * to do an allocation to replenish the inode free-list.
865 *
866 * This routine is designed to be called from xfs_create and
867 * xfs_create_dir.
868 *
869 */
870int
871xfs_dir_ialloc(
872 xfs_trans_t **tpp, /* input: current transaction;
873 output: may be a new transaction. */
874 xfs_inode_t *dp, /* directory within whose allocate
875 the inode. */
876 umode_t mode,
877 xfs_nlink_t nlink,
878 xfs_dev_t rdev,
879 prid_t prid, /* project id */
880 int okalloc, /* ok to allocate new space */
881 xfs_inode_t **ipp, /* pointer to inode; it will be
882 locked. */
883 int *committed)
884
885{
886 xfs_trans_t *tp;
887 xfs_trans_t *ntp;
888 xfs_inode_t *ip;
889 xfs_buf_t *ialloc_context = NULL;
890 int code;
891 void *dqinfo;
892 uint tflags;
893
894 tp = *tpp;
895 ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
896
897 /*
898 * xfs_ialloc will return a pointer to an incore inode if
899 * the Space Manager has an available inode on the free
900 * list. Otherwise, it will do an allocation and replenish
901 * the freelist. Since we can only do one allocation per
902 * transaction without deadlocks, we will need to commit the
903 * current transaction and start a new one. We will then
904 * need to call xfs_ialloc again to get the inode.
905 *
906 * If xfs_ialloc did an allocation to replenish the freelist,
907 * it returns the bp containing the head of the freelist as
908 * ialloc_context. We will hold a lock on it across the
909 * transaction commit so that no other process can steal
910 * the inode(s) that we've just allocated.
911 */
912 code = xfs_ialloc(tp, dp, mode, nlink, rdev, prid, okalloc,
913 &ialloc_context, &ip);
914
915 /*
916 * Return an error if we were unable to allocate a new inode.
917 * This should only happen if we run out of space on disk or
918 * encounter a disk error.
919 */
920 if (code) {
921 *ipp = NULL;
922 return code;
923 }
924 if (!ialloc_context && !ip) {
925 *ipp = NULL;
926 return XFS_ERROR(ENOSPC);
927 }
928
929 /*
930 * If the AGI buffer is non-NULL, then we were unable to get an
931 * inode in one operation. We need to commit the current
932 * transaction and call xfs_ialloc() again. It is guaranteed
933 * to succeed the second time.
934 */
935 if (ialloc_context) {
936 struct xfs_trans_res tres;
937
938 /*
939 * Normally, xfs_trans_commit releases all the locks.
940 * We call bhold to hang on to the ialloc_context across
941 * the commit. Holding this buffer prevents any other
942 * processes from doing any allocations in this
943 * allocation group.
944 */
945 xfs_trans_bhold(tp, ialloc_context);
946 /*
947 * Save the log reservation so we can use
948 * them in the next transaction.
949 */
950 tres.tr_logres = xfs_trans_get_log_res(tp);
951 tres.tr_logcount = xfs_trans_get_log_count(tp);
952
953 /*
954 * We want the quota changes to be associated with the next
955 * transaction, NOT this one. So, detach the dqinfo from this
956 * and attach it to the next transaction.
957 */
958 dqinfo = NULL;
959 tflags = 0;
960 if (tp->t_dqinfo) {
961 dqinfo = (void *)tp->t_dqinfo;
962 tp->t_dqinfo = NULL;
963 tflags = tp->t_flags & XFS_TRANS_DQ_DIRTY;
964 tp->t_flags &= ~(XFS_TRANS_DQ_DIRTY);
965 }
966
967 ntp = xfs_trans_dup(tp);
968 code = xfs_trans_commit(tp, 0);
969 tp = ntp;
970 if (committed != NULL) {
971 *committed = 1;
972 }
973 /*
974 * If we get an error during the commit processing,
975 * release the buffer that is still held and return
976 * to the caller.
977 */
978 if (code) {
979 xfs_buf_relse(ialloc_context);
980 if (dqinfo) {
981 tp->t_dqinfo = dqinfo;
982 xfs_trans_free_dqinfo(tp);
983 }
984 *tpp = ntp;
985 *ipp = NULL;
986 return code;
987 }
988
989 /*
990 * transaction commit worked ok so we can drop the extra ticket
991 * reference that we gained in xfs_trans_dup()
992 */
993 xfs_log_ticket_put(tp->t_ticket);
994 tres.tr_logflags = XFS_TRANS_PERM_LOG_RES;
995 code = xfs_trans_reserve(tp, &tres, 0, 0);
996
997 /*
998 * Re-attach the quota info that we detached from prev trx.
999 */
1000 if (dqinfo) {
1001 tp->t_dqinfo = dqinfo;
1002 tp->t_flags |= tflags;
1003 }
1004
1005 if (code) {
1006 xfs_buf_relse(ialloc_context);
1007 *tpp = ntp;
1008 *ipp = NULL;
1009 return code;
1010 }
1011 xfs_trans_bjoin(tp, ialloc_context);
1012
1013 /*
1014 * Call ialloc again. Since we've locked out all
1015 * other allocations in this allocation group,
1016 * this call should always succeed.
1017 */
1018 code = xfs_ialloc(tp, dp, mode, nlink, rdev, prid,
1019 okalloc, &ialloc_context, &ip);
1020
1021 /*
1022 * If we get an error at this point, return to the caller
1023 * so that the current transaction can be aborted.
1024 */
1025 if (code) {
1026 *tpp = tp;
1027 *ipp = NULL;
1028 return code;
1029 }
1030 ASSERT(!ialloc_context && ip);
1031
1032 } else {
1033 if (committed != NULL)
1034 *committed = 0;
1035 }
1036
1037 *ipp = ip;
1038 *tpp = tp;
1039
1040 return 0;
1041}
1042
1043/*
1044 * Decrement the link count on an inode & log the change.
1045 * If this causes the link count to go to zero, initiate the
1046 * logging activity required to truncate a file.
1047 */
1048int /* error */
1049xfs_droplink(
1050 xfs_trans_t *tp,
1051 xfs_inode_t *ip)
1052{
1053 int error;
1054
1055 xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
1056
1057 ASSERT (ip->i_d.di_nlink > 0);
1058 ip->i_d.di_nlink--;
1059 drop_nlink(VFS_I(ip));
1060 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1061
1062 error = 0;
1063 if (ip->i_d.di_nlink == 0) {
1064 /*
1065 * We're dropping the last link to this file.
1066 * Move the on-disk inode to the AGI unlinked list.
1067 * From xfs_inactive() we will pull the inode from
1068 * the list and free it.
1069 */
1070 error = xfs_iunlink(tp, ip);
1071 }
1072 return error;
1073}
1074
1075/*
1076 * This gets called when the inode's version needs to be changed from 1 to 2.
1077 * Currently this happens when the nlink field overflows the old 16-bit value
1078 * or when chproj is called to change the project for the first time.
1079 * As a side effect the superblock version will also get rev'd
1080 * to contain the NLINK bit.
1081 */
1082void
1083xfs_bump_ino_vers2(
1084 xfs_trans_t *tp,
1085 xfs_inode_t *ip)
1086{
1087 xfs_mount_t *mp;
1088
1089 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
1090 ASSERT(ip->i_d.di_version == 1);
1091
1092 ip->i_d.di_version = 2;
1093 ip->i_d.di_onlink = 0;
1094 memset(&(ip->i_d.di_pad[0]), 0, sizeof(ip->i_d.di_pad));
1095 mp = tp->t_mountp;
1096 if (!xfs_sb_version_hasnlink(&mp->m_sb)) {
1097 spin_lock(&mp->m_sb_lock);
1098 if (!xfs_sb_version_hasnlink(&mp->m_sb)) {
1099 xfs_sb_version_addnlink(&mp->m_sb);
1100 spin_unlock(&mp->m_sb_lock);
1101 xfs_mod_sb(tp, XFS_SB_VERSIONNUM);
1102 } else {
1103 spin_unlock(&mp->m_sb_lock);
1104 }
1105 }
1106 /* Caller must log the inode */
1107}
1108
1109/*
1110 * Increment the link count on an inode & log the change.
1111 */
1112int
1113xfs_bumplink(
1114 xfs_trans_t *tp,
1115 xfs_inode_t *ip)
1116{
1117 xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
1118
1119 ASSERT(ip->i_d.di_nlink > 0 || (VFS_I(ip)->i_state & I_LINKABLE));
1120 ip->i_d.di_nlink++;
1121 inc_nlink(VFS_I(ip));
1122 if ((ip->i_d.di_version == 1) &&
1123 (ip->i_d.di_nlink > XFS_MAXLINK_1)) {
1124 /*
1125 * The inode has increased its number of links beyond
1126 * what can fit in an old format inode. It now needs
1127 * to be converted to a version 2 inode with a 32 bit
1128 * link count. If this is the first inode in the file
1129 * system to do this, then we need to bump the superblock
1130 * version number as well.
1131 */
1132 xfs_bump_ino_vers2(tp, ip);
1133 }
1134
1135 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1136 return 0;
1137}
1138
1139int
1140xfs_create(
1141 xfs_inode_t *dp,
1142 struct xfs_name *name,
1143 umode_t mode,
1144 xfs_dev_t rdev,
1145 xfs_inode_t **ipp)
1146{
1147 int is_dir = S_ISDIR(mode);
1148 struct xfs_mount *mp = dp->i_mount;
1149 struct xfs_inode *ip = NULL;
1150 struct xfs_trans *tp = NULL;
1151 int error;
1152 xfs_bmap_free_t free_list;
1153 xfs_fsblock_t first_block;
1154 bool unlock_dp_on_error = false;
1155 uint cancel_flags;
1156 int committed;
1157 prid_t prid;
1158 struct xfs_dquot *udqp = NULL;
1159 struct xfs_dquot *gdqp = NULL;
1160 struct xfs_dquot *pdqp = NULL;
1161 struct xfs_trans_res tres;
1162 uint resblks;
1163
1164 trace_xfs_create(dp, name);
1165
1166 if (XFS_FORCED_SHUTDOWN(mp))
1167 return XFS_ERROR(EIO);
1168
1169 prid = xfs_get_initial_prid(dp);
1170
1171 /*
1172 * Make sure that we have allocated dquot(s) on disk.
1173 */
1174 error = xfs_qm_vop_dqalloc(dp, xfs_kuid_to_uid(current_fsuid()),
1175 xfs_kgid_to_gid(current_fsgid()), prid,
1176 XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
1177 &udqp, &gdqp, &pdqp);
1178 if (error)
1179 return error;
1180
1181 if (is_dir) {
1182 rdev = 0;
1183 resblks = XFS_MKDIR_SPACE_RES(mp, name->len);
1184 tres.tr_logres = M_RES(mp)->tr_mkdir.tr_logres;
1185 tres.tr_logcount = XFS_MKDIR_LOG_COUNT;
1186 tp = xfs_trans_alloc(mp, XFS_TRANS_MKDIR);
1187 } else {
1188 resblks = XFS_CREATE_SPACE_RES(mp, name->len);
1189 tres.tr_logres = M_RES(mp)->tr_create.tr_logres;
1190 tres.tr_logcount = XFS_CREATE_LOG_COUNT;
1191 tp = xfs_trans_alloc(mp, XFS_TRANS_CREATE);
1192 }
1193
1194 cancel_flags = XFS_TRANS_RELEASE_LOG_RES;
1195
1196 /*
1197 * Initially assume that the file does not exist and
1198 * reserve the resources for that case. If that is not
1199 * the case we'll drop the one we have and get a more
1200 * appropriate transaction later.
1201 */
1202 tres.tr_logflags = XFS_TRANS_PERM_LOG_RES;
1203 error = xfs_trans_reserve(tp, &tres, resblks, 0);
1204 if (error == ENOSPC) {
1205 /* flush outstanding delalloc blocks and retry */
1206 xfs_flush_inodes(mp);
1207 error = xfs_trans_reserve(tp, &tres, resblks, 0);
1208 }
1209 if (error == ENOSPC) {
1210 /* No space at all so try a "no-allocation" reservation */
1211 resblks = 0;
1212 error = xfs_trans_reserve(tp, &tres, 0, 0);
1213 }
1214 if (error) {
1215 cancel_flags = 0;
1216 goto out_trans_cancel;
1217 }
1218
1219 xfs_ilock(dp, XFS_ILOCK_EXCL | XFS_ILOCK_PARENT);
1220 unlock_dp_on_error = true;
1221
1222 xfs_bmap_init(&free_list, &first_block);
1223
1224 /*
1225 * Reserve disk quota and the inode.
1226 */
1227 error = xfs_trans_reserve_quota(tp, mp, udqp, gdqp,
1228 pdqp, resblks, 1, 0);
1229 if (error)
1230 goto out_trans_cancel;
1231
1232 error = xfs_dir_canenter(tp, dp, name, resblks);
1233 if (error)
1234 goto out_trans_cancel;
1235
1236 /*
1237 * A newly created regular or special file just has one directory
1238 * entry pointing to them, but a directory also the "." entry
1239 * pointing to itself.
1240 */
1241 error = xfs_dir_ialloc(&tp, dp, mode, is_dir ? 2 : 1, rdev,
1242 prid, resblks > 0, &ip, &committed);
1243 if (error) {
1244 if (error == ENOSPC)
1245 goto out_trans_cancel;
1246 goto out_trans_abort;
1247 }
1248
1249 /*
1250 * Now we join the directory inode to the transaction. We do not do it
1251 * earlier because xfs_dir_ialloc might commit the previous transaction
1252 * (and release all the locks). An error from here on will result in
1253 * the transaction cancel unlocking dp so don't do it explicitly in the
1254 * error path.
1255 */
1256 xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
1257 unlock_dp_on_error = false;
1258
1259 error = xfs_dir_createname(tp, dp, name, ip->i_ino,
1260 &first_block, &free_list, resblks ?
1261 resblks - XFS_IALLOC_SPACE_RES(mp) : 0);
1262 if (error) {
1263 ASSERT(error != ENOSPC);
1264 goto out_trans_abort;
1265 }
1266 xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1267 xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
1268
1269 if (is_dir) {
1270 error = xfs_dir_init(tp, ip, dp);
1271 if (error)
1272 goto out_bmap_cancel;
1273
1274 error = xfs_bumplink(tp, dp);
1275 if (error)
1276 goto out_bmap_cancel;
1277 }
1278
1279 /*
1280 * If this is a synchronous mount, make sure that the
1281 * create transaction goes to disk before returning to
1282 * the user.
1283 */
1284 if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
1285 xfs_trans_set_sync(tp);
1286
1287 /*
1288 * Attach the dquot(s) to the inodes and modify them incore.
1289 * These ids of the inode couldn't have changed since the new
1290 * inode has been locked ever since it was created.
1291 */
1292 xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp, pdqp);
1293
1294 error = xfs_bmap_finish(&tp, &free_list, &committed);
1295 if (error)
1296 goto out_bmap_cancel;
1297
1298 error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
1299 if (error)
1300 goto out_release_inode;
1301
1302 xfs_qm_dqrele(udqp);
1303 xfs_qm_dqrele(gdqp);
1304 xfs_qm_dqrele(pdqp);
1305
1306 *ipp = ip;
1307 return 0;
1308
1309 out_bmap_cancel:
1310 xfs_bmap_cancel(&free_list);
1311 out_trans_abort:
1312 cancel_flags |= XFS_TRANS_ABORT;
1313 out_trans_cancel:
1314 xfs_trans_cancel(tp, cancel_flags);
1315 out_release_inode:
1316 /*
1317 * Wait until after the current transaction is aborted to
1318 * release the inode. This prevents recursive transactions
1319 * and deadlocks from xfs_inactive.
1320 */
1321 if (ip)
1322 IRELE(ip);
1323
1324 xfs_qm_dqrele(udqp);
1325 xfs_qm_dqrele(gdqp);
1326 xfs_qm_dqrele(pdqp);
1327
1328 if (unlock_dp_on_error)
1329 xfs_iunlock(dp, XFS_ILOCK_EXCL);
1330 return error;
1331}
1332
1333int
1334xfs_create_tmpfile(
1335 struct xfs_inode *dp,
1336 struct dentry *dentry,
1337 umode_t mode,
1338 struct xfs_inode **ipp)
1339{
1340 struct xfs_mount *mp = dp->i_mount;
1341 struct xfs_inode *ip = NULL;
1342 struct xfs_trans *tp = NULL;
1343 int error;
1344 uint cancel_flags = XFS_TRANS_RELEASE_LOG_RES;
1345 prid_t prid;
1346 struct xfs_dquot *udqp = NULL;
1347 struct xfs_dquot *gdqp = NULL;
1348 struct xfs_dquot *pdqp = NULL;
1349 struct xfs_trans_res *tres;
1350 uint resblks;
1351
1352 if (XFS_FORCED_SHUTDOWN(mp))
1353 return XFS_ERROR(EIO);
1354
1355 prid = xfs_get_initial_prid(dp);
1356
1357 /*
1358 * Make sure that we have allocated dquot(s) on disk.
1359 */
1360 error = xfs_qm_vop_dqalloc(dp, xfs_kuid_to_uid(current_fsuid()),
1361 xfs_kgid_to_gid(current_fsgid()), prid,
1362 XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
1363 &udqp, &gdqp, &pdqp);
1364 if (error)
1365 return error;
1366
1367 resblks = XFS_IALLOC_SPACE_RES(mp);
1368 tp = xfs_trans_alloc(mp, XFS_TRANS_CREATE_TMPFILE);
1369
1370 tres = &M_RES(mp)->tr_create_tmpfile;
1371 error = xfs_trans_reserve(tp, tres, resblks, 0);
1372 if (error == ENOSPC) {
1373 /* No space at all so try a "no-allocation" reservation */
1374 resblks = 0;
1375 error = xfs_trans_reserve(tp, tres, 0, 0);
1376 }
1377 if (error) {
1378 cancel_flags = 0;
1379 goto out_trans_cancel;
1380 }
1381
1382 error = xfs_trans_reserve_quota(tp, mp, udqp, gdqp,
1383 pdqp, resblks, 1, 0);
1384 if (error)
1385 goto out_trans_cancel;
1386
1387 error = xfs_dir_ialloc(&tp, dp, mode, 1, 0,
1388 prid, resblks > 0, &ip, NULL);
1389 if (error) {
1390 if (error == ENOSPC)
1391 goto out_trans_cancel;
1392 goto out_trans_abort;
1393 }
1394
1395 if (mp->m_flags & XFS_MOUNT_WSYNC)
1396 xfs_trans_set_sync(tp);
1397
1398 /*
1399 * Attach the dquot(s) to the inodes and modify them incore.
1400 * These ids of the inode couldn't have changed since the new
1401 * inode has been locked ever since it was created.
1402 */
1403 xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp, pdqp);
1404
1405 ip->i_d.di_nlink--;
1406 error = xfs_iunlink(tp, ip);
1407 if (error)
1408 goto out_trans_abort;
1409
1410 error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
1411 if (error)
1412 goto out_release_inode;
1413
1414 xfs_qm_dqrele(udqp);
1415 xfs_qm_dqrele(gdqp);
1416 xfs_qm_dqrele(pdqp);
1417
1418 *ipp = ip;
1419 return 0;
1420
1421 out_trans_abort:
1422 cancel_flags |= XFS_TRANS_ABORT;
1423 out_trans_cancel:
1424 xfs_trans_cancel(tp, cancel_flags);
1425 out_release_inode:
1426 /*
1427 * Wait until after the current transaction is aborted to
1428 * release the inode. This prevents recursive transactions
1429 * and deadlocks from xfs_inactive.
1430 */
1431 if (ip)
1432 IRELE(ip);
1433
1434 xfs_qm_dqrele(udqp);
1435 xfs_qm_dqrele(gdqp);
1436 xfs_qm_dqrele(pdqp);
1437
1438 return error;
1439}
1440
1441int
1442xfs_link(
1443 xfs_inode_t *tdp,
1444 xfs_inode_t *sip,
1445 struct xfs_name *target_name)
1446{
1447 xfs_mount_t *mp = tdp->i_mount;
1448 xfs_trans_t *tp;
1449 int error;
1450 xfs_bmap_free_t free_list;
1451 xfs_fsblock_t first_block;
1452 int cancel_flags;
1453 int committed;
1454 int resblks;
1455
1456 trace_xfs_link(tdp, target_name);
1457
1458 ASSERT(!S_ISDIR(sip->i_d.di_mode));
1459
1460 if (XFS_FORCED_SHUTDOWN(mp))
1461 return XFS_ERROR(EIO);
1462
1463 error = xfs_qm_dqattach(sip, 0);
1464 if (error)
1465 goto std_return;
1466
1467 error = xfs_qm_dqattach(tdp, 0);
1468 if (error)
1469 goto std_return;
1470
1471 tp = xfs_trans_alloc(mp, XFS_TRANS_LINK);
1472 cancel_flags = XFS_TRANS_RELEASE_LOG_RES;
1473 resblks = XFS_LINK_SPACE_RES(mp, target_name->len);
1474 error = xfs_trans_reserve(tp, &M_RES(mp)->tr_link, resblks, 0);
1475 if (error == ENOSPC) {
1476 resblks = 0;
1477 error = xfs_trans_reserve(tp, &M_RES(mp)->tr_link, 0, 0);
1478 }
1479 if (error) {
1480 cancel_flags = 0;
1481 goto error_return;
1482 }
1483
1484 xfs_lock_two_inodes(sip, tdp, XFS_ILOCK_EXCL);
1485
1486 xfs_trans_ijoin(tp, sip, XFS_ILOCK_EXCL);
1487 xfs_trans_ijoin(tp, tdp, XFS_ILOCK_EXCL);
1488
1489 /*
1490 * If we are using project inheritance, we only allow hard link
1491 * creation in our tree when the project IDs are the same; else
1492 * the tree quota mechanism could be circumvented.
1493 */
1494 if (unlikely((tdp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) &&
1495 (xfs_get_projid(tdp) != xfs_get_projid(sip)))) {
1496 error = XFS_ERROR(EXDEV);
1497 goto error_return;
1498 }
1499
1500 error = xfs_dir_canenter(tp, tdp, target_name, resblks);
1501 if (error)
1502 goto error_return;
1503
1504 xfs_bmap_init(&free_list, &first_block);
1505
1506 if (sip->i_d.di_nlink == 0) {
1507 error = xfs_iunlink_remove(tp, sip);
1508 if (error)
1509 goto abort_return;
1510 }
1511
1512 error = xfs_dir_createname(tp, tdp, target_name, sip->i_ino,
1513 &first_block, &free_list, resblks);
1514 if (error)
1515 goto abort_return;
1516 xfs_trans_ichgtime(tp, tdp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1517 xfs_trans_log_inode(tp, tdp, XFS_ILOG_CORE);
1518
1519 error = xfs_bumplink(tp, sip);
1520 if (error)
1521 goto abort_return;
1522
1523 /*
1524 * If this is a synchronous mount, make sure that the
1525 * link transaction goes to disk before returning to
1526 * the user.
1527 */
1528 if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC)) {
1529 xfs_trans_set_sync(tp);
1530 }
1531
1532 error = xfs_bmap_finish (&tp, &free_list, &committed);
1533 if (error) {
1534 xfs_bmap_cancel(&free_list);
1535 goto abort_return;
1536 }
1537
1538 return xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
1539
1540 abort_return:
1541 cancel_flags |= XFS_TRANS_ABORT;
1542 error_return:
1543 xfs_trans_cancel(tp, cancel_flags);
1544 std_return:
1545 return error;
1546}
1547
1548/*
1549 * Free up the underlying blocks past new_size. The new size must be smaller
1550 * than the current size. This routine can be used both for the attribute and
1551 * data fork, and does not modify the inode size, which is left to the caller.
1552 *
1553 * The transaction passed to this routine must have made a permanent log
1554 * reservation of at least XFS_ITRUNCATE_LOG_RES. This routine may commit the
1555 * given transaction and start new ones, so make sure everything involved in
1556 * the transaction is tidy before calling here. Some transaction will be
1557 * returned to the caller to be committed. The incoming transaction must
1558 * already include the inode, and both inode locks must be held exclusively.
1559 * The inode must also be "held" within the transaction. On return the inode
1560 * will be "held" within the returned transaction. This routine does NOT
1561 * require any disk space to be reserved for it within the transaction.
1562 *
1563 * If we get an error, we must return with the inode locked and linked into the
1564 * current transaction. This keeps things simple for the higher level code,
1565 * because it always knows that the inode is locked and held in the transaction
1566 * that returns to it whether errors occur or not. We don't mark the inode
1567 * dirty on error so that transactions can be easily aborted if possible.
1568 */
1569int
1570xfs_itruncate_extents(
1571 struct xfs_trans **tpp,
1572 struct xfs_inode *ip,
1573 int whichfork,
1574 xfs_fsize_t new_size)
1575{
1576 struct xfs_mount *mp = ip->i_mount;
1577 struct xfs_trans *tp = *tpp;
1578 struct xfs_trans *ntp;
1579 xfs_bmap_free_t free_list;
1580 xfs_fsblock_t first_block;
1581 xfs_fileoff_t first_unmap_block;
1582 xfs_fileoff_t last_block;
1583 xfs_filblks_t unmap_len;
1584 int committed;
1585 int error = 0;
1586 int done = 0;
1587
1588 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
1589 ASSERT(!atomic_read(&VFS_I(ip)->i_count) ||
1590 xfs_isilocked(ip, XFS_IOLOCK_EXCL));
1591 ASSERT(new_size <= XFS_ISIZE(ip));
1592 ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
1593 ASSERT(ip->i_itemp != NULL);
1594 ASSERT(ip->i_itemp->ili_lock_flags == 0);
1595 ASSERT(!XFS_NOT_DQATTACHED(mp, ip));
1596
1597 trace_xfs_itruncate_extents_start(ip, new_size);
1598
1599 /*
1600 * Since it is possible for space to become allocated beyond
1601 * the end of the file (in a crash where the space is allocated
1602 * but the inode size is not yet updated), simply remove any
1603 * blocks which show up between the new EOF and the maximum
1604 * possible file size. If the first block to be removed is
1605 * beyond the maximum file size (ie it is the same as last_block),
1606 * then there is nothing to do.
1607 */
1608 first_unmap_block = XFS_B_TO_FSB(mp, (xfs_ufsize_t)new_size);
1609 last_block = XFS_B_TO_FSB(mp, mp->m_super->s_maxbytes);
1610 if (first_unmap_block == last_block)
1611 return 0;
1612
1613 ASSERT(first_unmap_block < last_block);
1614 unmap_len = last_block - first_unmap_block + 1;
1615 while (!done) {
1616 xfs_bmap_init(&free_list, &first_block);
1617 error = xfs_bunmapi(tp, ip,
1618 first_unmap_block, unmap_len,
1619 xfs_bmapi_aflag(whichfork),
1620 XFS_ITRUNC_MAX_EXTENTS,
1621 &first_block, &free_list,
1622 &done);
1623 if (error)
1624 goto out_bmap_cancel;
1625
1626 /*
1627 * Duplicate the transaction that has the permanent
1628 * reservation and commit the old transaction.
1629 */
1630 error = xfs_bmap_finish(&tp, &free_list, &committed);
1631 if (committed)
1632 xfs_trans_ijoin(tp, ip, 0);
1633 if (error)
1634 goto out_bmap_cancel;
1635
1636 if (committed) {
1637 /*
1638 * Mark the inode dirty so it will be logged and
1639 * moved forward in the log as part of every commit.
1640 */
1641 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1642 }
1643
1644 ntp = xfs_trans_dup(tp);
1645 error = xfs_trans_commit(tp, 0);
1646 tp = ntp;
1647
1648 xfs_trans_ijoin(tp, ip, 0);
1649
1650 if (error)
1651 goto out;
1652
1653 /*
1654 * Transaction commit worked ok so we can drop the extra ticket
1655 * reference that we gained in xfs_trans_dup()
1656 */
1657 xfs_log_ticket_put(tp->t_ticket);
1658 error = xfs_trans_reserve(tp, &M_RES(mp)->tr_itruncate, 0, 0);
1659 if (error)
1660 goto out;
1661 }
1662
1663 /*
1664 * Always re-log the inode so that our permanent transaction can keep
1665 * on rolling it forward in the log.
1666 */
1667 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1668
1669 trace_xfs_itruncate_extents_end(ip, new_size);
1670
1671out:
1672 *tpp = tp;
1673 return error;
1674out_bmap_cancel:
1675 /*
1676 * If the bunmapi call encounters an error, return to the caller where
1677 * the transaction can be properly aborted. We just need to make sure
1678 * we're not holding any resources that we were not when we came in.
1679 */
1680 xfs_bmap_cancel(&free_list);
1681 goto out;
1682}
1683
1684int
1685xfs_release(
1686 xfs_inode_t *ip)
1687{
1688 xfs_mount_t *mp = ip->i_mount;
1689 int error;
1690
1691 if (!S_ISREG(ip->i_d.di_mode) || (ip->i_d.di_mode == 0))
1692 return 0;
1693
1694 /* If this is a read-only mount, don't do this (would generate I/O) */
1695 if (mp->m_flags & XFS_MOUNT_RDONLY)
1696 return 0;
1697
1698 if (!XFS_FORCED_SHUTDOWN(mp)) {
1699 int truncated;
1700
1701 /*
1702 * If we are using filestreams, and we have an unlinked
1703 * file that we are processing the last close on, then nothing
1704 * will be able to reopen and write to this file. Purge this
1705 * inode from the filestreams cache so that it doesn't delay
1706 * teardown of the inode.
1707 */
1708 if ((ip->i_d.di_nlink == 0) && xfs_inode_is_filestream(ip))
1709 xfs_filestream_deassociate(ip);
1710
1711 /*
1712 * If we previously truncated this file and removed old data
1713 * in the process, we want to initiate "early" writeout on
1714 * the last close. This is an attempt to combat the notorious
1715 * NULL files problem which is particularly noticeable from a
1716 * truncate down, buffered (re-)write (delalloc), followed by
1717 * a crash. What we are effectively doing here is
1718 * significantly reducing the time window where we'd otherwise
1719 * be exposed to that problem.
1720 */
1721 truncated = xfs_iflags_test_and_clear(ip, XFS_ITRUNCATED);
1722 if (truncated) {
1723 xfs_iflags_clear(ip, XFS_IDIRTY_RELEASE);
1724 if (VN_DIRTY(VFS_I(ip)) && ip->i_delayed_blks > 0) {
1725 error = -filemap_flush(VFS_I(ip)->i_mapping);
1726 if (error)
1727 return error;
1728 }
1729 }
1730 }
1731
1732 if (ip->i_d.di_nlink == 0)
1733 return 0;
1734
1735 if (xfs_can_free_eofblocks(ip, false)) {
1736
1737 /*
1738 * If we can't get the iolock just skip truncating the blocks
1739 * past EOF because we could deadlock with the mmap_sem
1740 * otherwise. We'll get another chance to drop them once the
1741 * last reference to the inode is dropped, so we'll never leak
1742 * blocks permanently.
1743 *
1744 * Further, check if the inode is being opened, written and
1745 * closed frequently and we have delayed allocation blocks
1746 * outstanding (e.g. streaming writes from the NFS server),
1747 * truncating the blocks past EOF will cause fragmentation to
1748 * occur.
1749 *
1750 * In this case don't do the truncation, either, but we have to
1751 * be careful how we detect this case. Blocks beyond EOF show
1752 * up as i_delayed_blks even when the inode is clean, so we
1753 * need to truncate them away first before checking for a dirty
1754 * release. Hence on the first dirty close we will still remove
1755 * the speculative allocation, but after that we will leave it
1756 * in place.
1757 */
1758 if (xfs_iflags_test(ip, XFS_IDIRTY_RELEASE))
1759 return 0;
1760
1761 error = xfs_free_eofblocks(mp, ip, true);
1762 if (error && error != EAGAIN)
1763 return error;
1764
1765 /* delalloc blocks after truncation means it really is dirty */
1766 if (ip->i_delayed_blks)
1767 xfs_iflags_set(ip, XFS_IDIRTY_RELEASE);
1768 }
1769 return 0;
1770}
1771
1772/*
1773 * xfs_inactive_truncate
1774 *
1775 * Called to perform a truncate when an inode becomes unlinked.
1776 */
1777STATIC int
1778xfs_inactive_truncate(
1779 struct xfs_inode *ip)
1780{
1781 struct xfs_mount *mp = ip->i_mount;
1782 struct xfs_trans *tp;
1783 int error;
1784
1785 tp = xfs_trans_alloc(mp, XFS_TRANS_INACTIVE);
1786 error = xfs_trans_reserve(tp, &M_RES(mp)->tr_itruncate, 0, 0);
1787 if (error) {
1788 ASSERT(XFS_FORCED_SHUTDOWN(mp));
1789 xfs_trans_cancel(tp, 0);
1790 return error;
1791 }
1792
1793 xfs_ilock(ip, XFS_ILOCK_EXCL);
1794 xfs_trans_ijoin(tp, ip, 0);
1795
1796 /*
1797 * Log the inode size first to prevent stale data exposure in the event
1798 * of a system crash before the truncate completes. See the related
1799 * comment in xfs_setattr_size() for details.
1800 */
1801 ip->i_d.di_size = 0;
1802 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1803
1804 error = xfs_itruncate_extents(&tp, ip, XFS_DATA_FORK, 0);
1805 if (error)
1806 goto error_trans_cancel;
1807
1808 ASSERT(ip->i_d.di_nextents == 0);
1809
1810 error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
1811 if (error)
1812 goto error_unlock;
1813
1814 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1815 return 0;
1816
1817error_trans_cancel:
1818 xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
1819error_unlock:
1820 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1821 return error;
1822}
1823
1824/*
1825 * xfs_inactive_ifree()
1826 *
1827 * Perform the inode free when an inode is unlinked.
1828 */
1829STATIC int
1830xfs_inactive_ifree(
1831 struct xfs_inode *ip)
1832{
1833 xfs_bmap_free_t free_list;
1834 xfs_fsblock_t first_block;
1835 int committed;
1836 struct xfs_mount *mp = ip->i_mount;
1837 struct xfs_trans *tp;
1838 int error;
1839
1840 tp = xfs_trans_alloc(mp, XFS_TRANS_INACTIVE);
1841 error = xfs_trans_reserve(tp, &M_RES(mp)->tr_ifree, 0, 0);
1842 if (error) {
1843 ASSERT(XFS_FORCED_SHUTDOWN(mp));
1844 xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES);
1845 return error;
1846 }
1847
1848 xfs_ilock(ip, XFS_ILOCK_EXCL);
1849 xfs_trans_ijoin(tp, ip, 0);
1850
1851 xfs_bmap_init(&free_list, &first_block);
1852 error = xfs_ifree(tp, ip, &free_list);
1853 if (error) {
1854 /*
1855 * If we fail to free the inode, shut down. The cancel
1856 * might do that, we need to make sure. Otherwise the
1857 * inode might be lost for a long time or forever.
1858 */
1859 if (!XFS_FORCED_SHUTDOWN(mp)) {
1860 xfs_notice(mp, "%s: xfs_ifree returned error %d",
1861 __func__, error);
1862 xfs_force_shutdown(mp, SHUTDOWN_META_IO_ERROR);
1863 }
1864 xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES|XFS_TRANS_ABORT);
1865 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1866 return error;
1867 }
1868
1869 /*
1870 * Credit the quota account(s). The inode is gone.
1871 */
1872 xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_ICOUNT, -1);
1873
1874 /*
1875 * Just ignore errors at this point. There is nothing we can
1876 * do except to try to keep going. Make sure it's not a silent
1877 * error.
1878 */
1879 error = xfs_bmap_finish(&tp, &free_list, &committed);
1880 if (error)
1881 xfs_notice(mp, "%s: xfs_bmap_finish returned error %d",
1882 __func__, error);
1883 error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
1884 if (error)
1885 xfs_notice(mp, "%s: xfs_trans_commit returned error %d",
1886 __func__, error);
1887
1888 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1889 return 0;
1890}
1891
1892/*
1893 * xfs_inactive
1894 *
1895 * This is called when the vnode reference count for the vnode
1896 * goes to zero. If the file has been unlinked, then it must
1897 * now be truncated. Also, we clear all of the read-ahead state
1898 * kept for the inode here since the file is now closed.
1899 */
1900void
1901xfs_inactive(
1902 xfs_inode_t *ip)
1903{
1904 struct xfs_mount *mp;
1905 int error;
1906 int truncate = 0;
1907
1908 /*
1909 * If the inode is already free, then there can be nothing
1910 * to clean up here.
1911 */
1912 if (ip->i_d.di_mode == 0) {
1913 ASSERT(ip->i_df.if_real_bytes == 0);
1914 ASSERT(ip->i_df.if_broot_bytes == 0);
1915 return;
1916 }
1917
1918 mp = ip->i_mount;
1919
1920 /* If this is a read-only mount, don't do this (would generate I/O) */
1921 if (mp->m_flags & XFS_MOUNT_RDONLY)
1922 return;
1923
1924 if (ip->i_d.di_nlink != 0) {
1925 /*
1926 * force is true because we are evicting an inode from the
1927 * cache. Post-eof blocks must be freed, lest we end up with
1928 * broken free space accounting.
1929 */
1930 if (xfs_can_free_eofblocks(ip, true))
1931 xfs_free_eofblocks(mp, ip, false);
1932
1933 return;
1934 }
1935
1936 if (S_ISREG(ip->i_d.di_mode) &&
1937 (ip->i_d.di_size != 0 || XFS_ISIZE(ip) != 0 ||
1938 ip->i_d.di_nextents > 0 || ip->i_delayed_blks > 0))
1939 truncate = 1;
1940
1941 error = xfs_qm_dqattach(ip, 0);
1942 if (error)
1943 return;
1944
1945 if (S_ISLNK(ip->i_d.di_mode))
1946 error = xfs_inactive_symlink(ip);
1947 else if (truncate)
1948 error = xfs_inactive_truncate(ip);
1949 if (error)
1950 return;
1951
1952 /*
1953 * If there are attributes associated with the file then blow them away
1954 * now. The code calls a routine that recursively deconstructs the
1955 * attribute fork. We need to just commit the current transaction
1956 * because we can't use it for xfs_attr_inactive().
1957 */
1958 if (ip->i_d.di_anextents > 0) {
1959 ASSERT(ip->i_d.di_forkoff != 0);
1960
1961 error = xfs_attr_inactive(ip);
1962 if (error)
1963 return;
1964 }
1965
1966 if (ip->i_afp)
1967 xfs_idestroy_fork(ip, XFS_ATTR_FORK);
1968
1969 ASSERT(ip->i_d.di_anextents == 0);
1970
1971 /*
1972 * Free the inode.
1973 */
1974 error = xfs_inactive_ifree(ip);
1975 if (error)
1976 return;
1977
1978 /*
1979 * Release the dquots held by inode, if any.
1980 */
1981 xfs_qm_dqdetach(ip);
1982}
1983
1984/*
1985 * This is called when the inode's link count goes to 0.
1986 * We place the on-disk inode on a list in the AGI. It
1987 * will be pulled from this list when the inode is freed.
1988 */
1989int
1990xfs_iunlink(
1991 xfs_trans_t *tp,
1992 xfs_inode_t *ip)
1993{
1994 xfs_mount_t *mp;
1995 xfs_agi_t *agi;
1996 xfs_dinode_t *dip;
1997 xfs_buf_t *agibp;
1998 xfs_buf_t *ibp;
1999 xfs_agino_t agino;
2000 short bucket_index;
2001 int offset;
2002 int error;
2003
2004 ASSERT(ip->i_d.di_nlink == 0);
2005 ASSERT(ip->i_d.di_mode != 0);
2006
2007 mp = tp->t_mountp;
2008
2009 /*
2010 * Get the agi buffer first. It ensures lock ordering
2011 * on the list.
2012 */
2013 error = xfs_read_agi(mp, tp, XFS_INO_TO_AGNO(mp, ip->i_ino), &agibp);
2014 if (error)
2015 return error;
2016 agi = XFS_BUF_TO_AGI(agibp);
2017
2018 /*
2019 * Get the index into the agi hash table for the
2020 * list this inode will go on.
2021 */
2022 agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
2023 ASSERT(agino != 0);
2024 bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
2025 ASSERT(agi->agi_unlinked[bucket_index]);
2026 ASSERT(be32_to_cpu(agi->agi_unlinked[bucket_index]) != agino);
2027
2028 if (agi->agi_unlinked[bucket_index] != cpu_to_be32(NULLAGINO)) {
2029 /*
2030 * There is already another inode in the bucket we need
2031 * to add ourselves to. Add us at the front of the list.
2032 * Here we put the head pointer into our next pointer,
2033 * and then we fall through to point the head at us.
2034 */
2035 error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &ibp,
2036 0, 0);
2037 if (error)
2038 return error;
2039
2040 ASSERT(dip->di_next_unlinked == cpu_to_be32(NULLAGINO));
2041 dip->di_next_unlinked = agi->agi_unlinked[bucket_index];
2042 offset = ip->i_imap.im_boffset +
2043 offsetof(xfs_dinode_t, di_next_unlinked);
2044
2045 /* need to recalc the inode CRC if appropriate */
2046 xfs_dinode_calc_crc(mp, dip);
2047
2048 xfs_trans_inode_buf(tp, ibp);
2049 xfs_trans_log_buf(tp, ibp, offset,
2050 (offset + sizeof(xfs_agino_t) - 1));
2051 xfs_inobp_check(mp, ibp);
2052 }
2053
2054 /*
2055 * Point the bucket head pointer at the inode being inserted.
2056 */
2057 ASSERT(agino != 0);
2058 agi->agi_unlinked[bucket_index] = cpu_to_be32(agino);
2059 offset = offsetof(xfs_agi_t, agi_unlinked) +
2060 (sizeof(xfs_agino_t) * bucket_index);
2061 xfs_trans_log_buf(tp, agibp, offset,
2062 (offset + sizeof(xfs_agino_t) - 1));
2063 return 0;
2064}
2065
2066/*
2067 * Pull the on-disk inode from the AGI unlinked list.
2068 */
2069STATIC int
2070xfs_iunlink_remove(
2071 xfs_trans_t *tp,
2072 xfs_inode_t *ip)
2073{
2074 xfs_ino_t next_ino;
2075 xfs_mount_t *mp;
2076 xfs_agi_t *agi;
2077 xfs_dinode_t *dip;
2078 xfs_buf_t *agibp;
2079 xfs_buf_t *ibp;
2080 xfs_agnumber_t agno;
2081 xfs_agino_t agino;
2082 xfs_agino_t next_agino;
2083 xfs_buf_t *last_ibp;
2084 xfs_dinode_t *last_dip = NULL;
2085 short bucket_index;
2086 int offset, last_offset = 0;
2087 int error;
2088
2089 mp = tp->t_mountp;
2090 agno = XFS_INO_TO_AGNO(mp, ip->i_ino);
2091
2092 /*
2093 * Get the agi buffer first. It ensures lock ordering
2094 * on the list.
2095 */
2096 error = xfs_read_agi(mp, tp, agno, &agibp);
2097 if (error)
2098 return error;
2099
2100 agi = XFS_BUF_TO_AGI(agibp);
2101
2102 /*
2103 * Get the index into the agi hash table for the
2104 * list this inode will go on.
2105 */
2106 agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
2107 ASSERT(agino != 0);
2108 bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
2109 ASSERT(agi->agi_unlinked[bucket_index] != cpu_to_be32(NULLAGINO));
2110 ASSERT(agi->agi_unlinked[bucket_index]);
2111
2112 if (be32_to_cpu(agi->agi_unlinked[bucket_index]) == agino) {
2113 /*
2114 * We're at the head of the list. Get the inode's on-disk
2115 * buffer to see if there is anyone after us on the list.
2116 * Only modify our next pointer if it is not already NULLAGINO.
2117 * This saves us the overhead of dealing with the buffer when
2118 * there is no need to change it.
2119 */
2120 error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &ibp,
2121 0, 0);
2122 if (error) {
2123 xfs_warn(mp, "%s: xfs_imap_to_bp returned error %d.",
2124 __func__, error);
2125 return error;
2126 }
2127 next_agino = be32_to_cpu(dip->di_next_unlinked);
2128 ASSERT(next_agino != 0);
2129 if (next_agino != NULLAGINO) {
2130 dip->di_next_unlinked = cpu_to_be32(NULLAGINO);
2131 offset = ip->i_imap.im_boffset +
2132 offsetof(xfs_dinode_t, di_next_unlinked);
2133
2134 /* need to recalc the inode CRC if appropriate */
2135 xfs_dinode_calc_crc(mp, dip);
2136
2137 xfs_trans_inode_buf(tp, ibp);
2138 xfs_trans_log_buf(tp, ibp, offset,
2139 (offset + sizeof(xfs_agino_t) - 1));
2140 xfs_inobp_check(mp, ibp);
2141 } else {
2142 xfs_trans_brelse(tp, ibp);
2143 }
2144 /*
2145 * Point the bucket head pointer at the next inode.
2146 */
2147 ASSERT(next_agino != 0);
2148 ASSERT(next_agino != agino);
2149 agi->agi_unlinked[bucket_index] = cpu_to_be32(next_agino);
2150 offset = offsetof(xfs_agi_t, agi_unlinked) +
2151 (sizeof(xfs_agino_t) * bucket_index);
2152 xfs_trans_log_buf(tp, agibp, offset,
2153 (offset + sizeof(xfs_agino_t) - 1));
2154 } else {
2155 /*
2156 * We need to search the list for the inode being freed.
2157 */
2158 next_agino = be32_to_cpu(agi->agi_unlinked[bucket_index]);
2159 last_ibp = NULL;
2160 while (next_agino != agino) {
2161 struct xfs_imap imap;
2162
2163 if (last_ibp)
2164 xfs_trans_brelse(tp, last_ibp);
2165
2166 imap.im_blkno = 0;
2167 next_ino = XFS_AGINO_TO_INO(mp, agno, next_agino);
2168
2169 error = xfs_imap(mp, tp, next_ino, &imap, 0);
2170 if (error) {
2171 xfs_warn(mp,
2172 "%s: xfs_imap returned error %d.",
2173 __func__, error);
2174 return error;
2175 }
2176
2177 error = xfs_imap_to_bp(mp, tp, &imap, &last_dip,
2178 &last_ibp, 0, 0);
2179 if (error) {
2180 xfs_warn(mp,
2181 "%s: xfs_imap_to_bp returned error %d.",
2182 __func__, error);
2183 return error;
2184 }
2185
2186 last_offset = imap.im_boffset;
2187 next_agino = be32_to_cpu(last_dip->di_next_unlinked);
2188 ASSERT(next_agino != NULLAGINO);
2189 ASSERT(next_agino != 0);
2190 }
2191
2192 /*
2193 * Now last_ibp points to the buffer previous to us on the
2194 * unlinked list. Pull us from the list.
2195 */
2196 error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &ibp,
2197 0, 0);
2198 if (error) {
2199 xfs_warn(mp, "%s: xfs_imap_to_bp(2) returned error %d.",
2200 __func__, error);
2201 return error;
2202 }
2203 next_agino = be32_to_cpu(dip->di_next_unlinked);
2204 ASSERT(next_agino != 0);
2205 ASSERT(next_agino != agino);
2206 if (next_agino != NULLAGINO) {
2207 dip->di_next_unlinked = cpu_to_be32(NULLAGINO);
2208 offset = ip->i_imap.im_boffset +
2209 offsetof(xfs_dinode_t, di_next_unlinked);
2210
2211 /* need to recalc the inode CRC if appropriate */
2212 xfs_dinode_calc_crc(mp, dip);
2213
2214 xfs_trans_inode_buf(tp, ibp);
2215 xfs_trans_log_buf(tp, ibp, offset,
2216 (offset + sizeof(xfs_agino_t) - 1));
2217 xfs_inobp_check(mp, ibp);
2218 } else {
2219 xfs_trans_brelse(tp, ibp);
2220 }
2221 /*
2222 * Point the previous inode on the list to the next inode.
2223 */
2224 last_dip->di_next_unlinked = cpu_to_be32(next_agino);
2225 ASSERT(next_agino != 0);
2226 offset = last_offset + offsetof(xfs_dinode_t, di_next_unlinked);
2227
2228 /* need to recalc the inode CRC if appropriate */
2229 xfs_dinode_calc_crc(mp, last_dip);
2230
2231 xfs_trans_inode_buf(tp, last_ibp);
2232 xfs_trans_log_buf(tp, last_ibp, offset,
2233 (offset + sizeof(xfs_agino_t) - 1));
2234 xfs_inobp_check(mp, last_ibp);
2235 }
2236 return 0;
2237}
2238
2239/*
2240 * A big issue when freeing the inode cluster is that we _cannot_ skip any
2241 * inodes that are in memory - they all must be marked stale and attached to
2242 * the cluster buffer.
2243 */
2244STATIC int
2245xfs_ifree_cluster(
2246 xfs_inode_t *free_ip,
2247 xfs_trans_t *tp,
2248 xfs_ino_t inum)
2249{
2250 xfs_mount_t *mp = free_ip->i_mount;
2251 int blks_per_cluster;
2252 int inodes_per_cluster;
2253 int nbufs;
2254 int i, j;
2255 xfs_daddr_t blkno;
2256 xfs_buf_t *bp;
2257 xfs_inode_t *ip;
2258 xfs_inode_log_item_t *iip;
2259 xfs_log_item_t *lip;
2260 struct xfs_perag *pag;
2261
2262 pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, inum));
2263 blks_per_cluster = xfs_icluster_size_fsb(mp);
2264 inodes_per_cluster = blks_per_cluster << mp->m_sb.sb_inopblog;
2265 nbufs = mp->m_ialloc_blks / blks_per_cluster;
2266
2267 for (j = 0; j < nbufs; j++, inum += inodes_per_cluster) {
2268 blkno = XFS_AGB_TO_DADDR(mp, XFS_INO_TO_AGNO(mp, inum),
2269 XFS_INO_TO_AGBNO(mp, inum));
2270
2271 /*
2272 * We obtain and lock the backing buffer first in the process
2273 * here, as we have to ensure that any dirty inode that we
2274 * can't get the flush lock on is attached to the buffer.
2275 * If we scan the in-memory inodes first, then buffer IO can
2276 * complete before we get a lock on it, and hence we may fail
2277 * to mark all the active inodes on the buffer stale.
2278 */
2279 bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, blkno,
2280 mp->m_bsize * blks_per_cluster,
2281 XBF_UNMAPPED);
2282
2283 if (!bp)
2284 return ENOMEM;
2285
2286 /*
2287 * This buffer may not have been correctly initialised as we
2288 * didn't read it from disk. That's not important because we are
2289 * only using to mark the buffer as stale in the log, and to
2290 * attach stale cached inodes on it. That means it will never be
2291 * dispatched for IO. If it is, we want to know about it, and we
2292 * want it to fail. We can acheive this by adding a write
2293 * verifier to the buffer.
2294 */
2295 bp->b_ops = &xfs_inode_buf_ops;
2296
2297 /*
2298 * Walk the inodes already attached to the buffer and mark them
2299 * stale. These will all have the flush locks held, so an
2300 * in-memory inode walk can't lock them. By marking them all
2301 * stale first, we will not attempt to lock them in the loop
2302 * below as the XFS_ISTALE flag will be set.
2303 */
2304 lip = bp->b_fspriv;
2305 while (lip) {
2306 if (lip->li_type == XFS_LI_INODE) {
2307 iip = (xfs_inode_log_item_t *)lip;
2308 ASSERT(iip->ili_logged == 1);
2309 lip->li_cb = xfs_istale_done;
2310 xfs_trans_ail_copy_lsn(mp->m_ail,
2311 &iip->ili_flush_lsn,
2312 &iip->ili_item.li_lsn);
2313 xfs_iflags_set(iip->ili_inode, XFS_ISTALE);
2314 }
2315 lip = lip->li_bio_list;
2316 }
2317
2318
2319 /*
2320 * For each inode in memory attempt to add it to the inode
2321 * buffer and set it up for being staled on buffer IO
2322 * completion. This is safe as we've locked out tail pushing
2323 * and flushing by locking the buffer.
2324 *
2325 * We have already marked every inode that was part of a
2326 * transaction stale above, which means there is no point in
2327 * even trying to lock them.
2328 */
2329 for (i = 0; i < inodes_per_cluster; i++) {
2330retry:
2331 rcu_read_lock();
2332 ip = radix_tree_lookup(&pag->pag_ici_root,
2333 XFS_INO_TO_AGINO(mp, (inum + i)));
2334
2335 /* Inode not in memory, nothing to do */
2336 if (!ip) {
2337 rcu_read_unlock();
2338 continue;
2339 }
2340
2341 /*
2342 * because this is an RCU protected lookup, we could
2343 * find a recently freed or even reallocated inode
2344 * during the lookup. We need to check under the
2345 * i_flags_lock for a valid inode here. Skip it if it
2346 * is not valid, the wrong inode or stale.
2347 */
2348 spin_lock(&ip->i_flags_lock);
2349 if (ip->i_ino != inum + i ||
2350 __xfs_iflags_test(ip, XFS_ISTALE)) {
2351 spin_unlock(&ip->i_flags_lock);
2352 rcu_read_unlock();
2353 continue;
2354 }
2355 spin_unlock(&ip->i_flags_lock);
2356
2357 /*
2358 * Don't try to lock/unlock the current inode, but we
2359 * _cannot_ skip the other inodes that we did not find
2360 * in the list attached to the buffer and are not
2361 * already marked stale. If we can't lock it, back off
2362 * and retry.
2363 */
2364 if (ip != free_ip &&
2365 !xfs_ilock_nowait(ip, XFS_ILOCK_EXCL)) {
2366 rcu_read_unlock();
2367 delay(1);
2368 goto retry;
2369 }
2370 rcu_read_unlock();
2371
2372 xfs_iflock(ip);
2373 xfs_iflags_set(ip, XFS_ISTALE);
2374
2375 /*
2376 * we don't need to attach clean inodes or those only
2377 * with unlogged changes (which we throw away, anyway).
2378 */
2379 iip = ip->i_itemp;
2380 if (!iip || xfs_inode_clean(ip)) {
2381 ASSERT(ip != free_ip);
2382 xfs_ifunlock(ip);
2383 xfs_iunlock(ip, XFS_ILOCK_EXCL);
2384 continue;
2385 }
2386
2387 iip->ili_last_fields = iip->ili_fields;
2388 iip->ili_fields = 0;
2389 iip->ili_logged = 1;
2390 xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn,
2391 &iip->ili_item.li_lsn);
2392
2393 xfs_buf_attach_iodone(bp, xfs_istale_done,
2394 &iip->ili_item);
2395
2396 if (ip != free_ip)
2397 xfs_iunlock(ip, XFS_ILOCK_EXCL);
2398 }
2399
2400 xfs_trans_stale_inode_buf(tp, bp);
2401 xfs_trans_binval(tp, bp);
2402 }
2403
2404 xfs_perag_put(pag);
2405 return 0;
2406}
2407
2408/*
2409 * This is called to return an inode to the inode free list.
2410 * The inode should already be truncated to 0 length and have
2411 * no pages associated with it. This routine also assumes that
2412 * the inode is already a part of the transaction.
2413 *
2414 * The on-disk copy of the inode will have been added to the list
2415 * of unlinked inodes in the AGI. We need to remove the inode from
2416 * that list atomically with respect to freeing it here.
2417 */
2418int
2419xfs_ifree(
2420 xfs_trans_t *tp,
2421 xfs_inode_t *ip,
2422 xfs_bmap_free_t *flist)
2423{
2424 int error;
2425 int delete;
2426 xfs_ino_t first_ino;
2427
2428 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
2429 ASSERT(ip->i_d.di_nlink == 0);
2430 ASSERT(ip->i_d.di_nextents == 0);
2431 ASSERT(ip->i_d.di_anextents == 0);
2432 ASSERT(ip->i_d.di_size == 0 || !S_ISREG(ip->i_d.di_mode));
2433 ASSERT(ip->i_d.di_nblocks == 0);
2434
2435 /*
2436 * Pull the on-disk inode from the AGI unlinked list.
2437 */
2438 error = xfs_iunlink_remove(tp, ip);
2439 if (error)
2440 return error;
2441
2442 error = xfs_difree(tp, ip->i_ino, flist, &delete, &first_ino);
2443 if (error)
2444 return error;
2445
2446 ip->i_d.di_mode = 0; /* mark incore inode as free */
2447 ip->i_d.di_flags = 0;
2448 ip->i_d.di_dmevmask = 0;
2449 ip->i_d.di_forkoff = 0; /* mark the attr fork not in use */
2450 ip->i_d.di_format = XFS_DINODE_FMT_EXTENTS;
2451 ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;
2452 /*
2453 * Bump the generation count so no one will be confused
2454 * by reincarnations of this inode.
2455 */
2456 ip->i_d.di_gen++;
2457 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
2458
2459 if (delete)
2460 error = xfs_ifree_cluster(ip, tp, first_ino);
2461
2462 return error;
2463}
2464
2465/*
2466 * This is called to unpin an inode. The caller must have the inode locked
2467 * in at least shared mode so that the buffer cannot be subsequently pinned
2468 * once someone is waiting for it to be unpinned.
2469 */
2470static void
2471xfs_iunpin(
2472 struct xfs_inode *ip)
2473{
2474 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
2475
2476 trace_xfs_inode_unpin_nowait(ip, _RET_IP_);
2477
2478 /* Give the log a push to start the unpinning I/O */
2479 xfs_log_force_lsn(ip->i_mount, ip->i_itemp->ili_last_lsn, 0);
2480
2481}
2482
2483static void
2484__xfs_iunpin_wait(
2485 struct xfs_inode *ip)
2486{
2487 wait_queue_head_t *wq = bit_waitqueue(&ip->i_flags, __XFS_IPINNED_BIT);
2488 DEFINE_WAIT_BIT(wait, &ip->i_flags, __XFS_IPINNED_BIT);
2489
2490 xfs_iunpin(ip);
2491
2492 do {
2493 prepare_to_wait(wq, &wait.wait, TASK_UNINTERRUPTIBLE);
2494 if (xfs_ipincount(ip))
2495 io_schedule();
2496 } while (xfs_ipincount(ip));
2497 finish_wait(wq, &wait.wait);
2498}
2499
2500void
2501xfs_iunpin_wait(
2502 struct xfs_inode *ip)
2503{
2504 if (xfs_ipincount(ip))
2505 __xfs_iunpin_wait(ip);
2506}
2507
2508/*
2509 * Removing an inode from the namespace involves removing the directory entry
2510 * and dropping the link count on the inode. Removing the directory entry can
2511 * result in locking an AGF (directory blocks were freed) and removing a link
2512 * count can result in placing the inode on an unlinked list which results in
2513 * locking an AGI.
2514 *
2515 * The big problem here is that we have an ordering constraint on AGF and AGI
2516 * locking - inode allocation locks the AGI, then can allocate a new extent for
2517 * new inodes, locking the AGF after the AGI. Similarly, freeing the inode
2518 * removes the inode from the unlinked list, requiring that we lock the AGI
2519 * first, and then freeing the inode can result in an inode chunk being freed
2520 * and hence freeing disk space requiring that we lock an AGF.
2521 *
2522 * Hence the ordering that is imposed by other parts of the code is AGI before
2523 * AGF. This means we cannot remove the directory entry before we drop the inode
2524 * reference count and put it on the unlinked list as this results in a lock
2525 * order of AGF then AGI, and this can deadlock against inode allocation and
2526 * freeing. Therefore we must drop the link counts before we remove the
2527 * directory entry.
2528 *
2529 * This is still safe from a transactional point of view - it is not until we
2530 * get to xfs_bmap_finish() that we have the possibility of multiple
2531 * transactions in this operation. Hence as long as we remove the directory
2532 * entry and drop the link count in the first transaction of the remove
2533 * operation, there are no transactional constraints on the ordering here.
2534 */
2535int
2536xfs_remove(
2537 xfs_inode_t *dp,
2538 struct xfs_name *name,
2539 xfs_inode_t *ip)
2540{
2541 xfs_mount_t *mp = dp->i_mount;
2542 xfs_trans_t *tp = NULL;
2543 int is_dir = S_ISDIR(ip->i_d.di_mode);
2544 int error = 0;
2545 xfs_bmap_free_t free_list;
2546 xfs_fsblock_t first_block;
2547 int cancel_flags;
2548 int committed;
2549 int link_zero;
2550 uint resblks;
2551 uint log_count;
2552
2553 trace_xfs_remove(dp, name);
2554
2555 if (XFS_FORCED_SHUTDOWN(mp))
2556 return XFS_ERROR(EIO);
2557
2558 error = xfs_qm_dqattach(dp, 0);
2559 if (error)
2560 goto std_return;
2561
2562 error = xfs_qm_dqattach(ip, 0);
2563 if (error)
2564 goto std_return;
2565
2566 if (is_dir) {
2567 tp = xfs_trans_alloc(mp, XFS_TRANS_RMDIR);
2568 log_count = XFS_DEFAULT_LOG_COUNT;
2569 } else {
2570 tp = xfs_trans_alloc(mp, XFS_TRANS_REMOVE);
2571 log_count = XFS_REMOVE_LOG_COUNT;
2572 }
2573 cancel_flags = XFS_TRANS_RELEASE_LOG_RES;
2574
2575 /*
2576 * We try to get the real space reservation first,
2577 * allowing for directory btree deletion(s) implying
2578 * possible bmap insert(s). If we can't get the space
2579 * reservation then we use 0 instead, and avoid the bmap
2580 * btree insert(s) in the directory code by, if the bmap
2581 * insert tries to happen, instead trimming the LAST
2582 * block from the directory.
2583 */
2584 resblks = XFS_REMOVE_SPACE_RES(mp);
2585 error = xfs_trans_reserve(tp, &M_RES(mp)->tr_remove, resblks, 0);
2586 if (error == ENOSPC) {
2587 resblks = 0;
2588 error = xfs_trans_reserve(tp, &M_RES(mp)->tr_remove, 0, 0);
2589 }
2590 if (error) {
2591 ASSERT(error != ENOSPC);
2592 cancel_flags = 0;
2593 goto out_trans_cancel;
2594 }
2595
2596 xfs_lock_two_inodes(dp, ip, XFS_ILOCK_EXCL);
2597
2598 xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
2599 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
2600
2601 /*
2602 * If we're removing a directory perform some additional validation.
2603 */
2604 cancel_flags |= XFS_TRANS_ABORT;
2605 if (is_dir) {
2606 ASSERT(ip->i_d.di_nlink >= 2);
2607 if (ip->i_d.di_nlink != 2) {
2608 error = XFS_ERROR(ENOTEMPTY);
2609 goto out_trans_cancel;
2610 }
2611 if (!xfs_dir_isempty(ip)) {
2612 error = XFS_ERROR(ENOTEMPTY);
2613 goto out_trans_cancel;
2614 }
2615
2616 /* Drop the link from ip's "..". */
2617 error = xfs_droplink(tp, dp);
2618 if (error)
2619 goto out_trans_cancel;
2620
2621 /* Drop the "." link from ip to self. */
2622 error = xfs_droplink(tp, ip);
2623 if (error)
2624 goto out_trans_cancel;
2625 } else {
2626 /*
2627 * When removing a non-directory we need to log the parent
2628 * inode here. For a directory this is done implicitly
2629 * by the xfs_droplink call for the ".." entry.
2630 */
2631 xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
2632 }
2633 xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2634
2635 /* Drop the link from dp to ip. */
2636 error = xfs_droplink(tp, ip);
2637 if (error)
2638 goto out_trans_cancel;
2639
2640 /* Determine if this is the last link while the inode is locked */
2641 link_zero = (ip->i_d.di_nlink == 0);
2642
2643 xfs_bmap_init(&free_list, &first_block);
2644 error = xfs_dir_removename(tp, dp, name, ip->i_ino,
2645 &first_block, &free_list, resblks);
2646 if (error) {
2647 ASSERT(error != ENOENT);
2648 goto out_bmap_cancel;
2649 }
2650
2651 /*
2652 * If this is a synchronous mount, make sure that the
2653 * remove transaction goes to disk before returning to
2654 * the user.
2655 */
2656 if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
2657 xfs_trans_set_sync(tp);
2658
2659 error = xfs_bmap_finish(&tp, &free_list, &committed);
2660 if (error)
2661 goto out_bmap_cancel;
2662
2663 error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
2664 if (error)
2665 goto std_return;
2666
2667 /*
2668 * If we are using filestreams, kill the stream association.
2669 * If the file is still open it may get a new one but that
2670 * will get killed on last close in xfs_close() so we don't
2671 * have to worry about that.
2672 */
2673 if (!is_dir && link_zero && xfs_inode_is_filestream(ip))
2674 xfs_filestream_deassociate(ip);
2675
2676 return 0;
2677
2678 out_bmap_cancel:
2679 xfs_bmap_cancel(&free_list);
2680 out_trans_cancel:
2681 xfs_trans_cancel(tp, cancel_flags);
2682 std_return:
2683 return error;
2684}
2685
2686/*
2687 * Enter all inodes for a rename transaction into a sorted array.
2688 */
2689STATIC void
2690xfs_sort_for_rename(
2691 xfs_inode_t *dp1, /* in: old (source) directory inode */
2692 xfs_inode_t *dp2, /* in: new (target) directory inode */
2693 xfs_inode_t *ip1, /* in: inode of old entry */
2694 xfs_inode_t *ip2, /* in: inode of new entry, if it
2695 already exists, NULL otherwise. */
2696 xfs_inode_t **i_tab,/* out: array of inode returned, sorted */
2697 int *num_inodes) /* out: number of inodes in array */
2698{
2699 xfs_inode_t *temp;
2700 int i, j;
2701
2702 /*
2703 * i_tab contains a list of pointers to inodes. We initialize
2704 * the table here & we'll sort it. We will then use it to
2705 * order the acquisition of the inode locks.
2706 *
2707 * Note that the table may contain duplicates. e.g., dp1 == dp2.
2708 */
2709 i_tab[0] = dp1;
2710 i_tab[1] = dp2;
2711 i_tab[2] = ip1;
2712 if (ip2) {
2713 *num_inodes = 4;
2714 i_tab[3] = ip2;
2715 } else {
2716 *num_inodes = 3;
2717 i_tab[3] = NULL;
2718 }
2719
2720 /*
2721 * Sort the elements via bubble sort. (Remember, there are at
2722 * most 4 elements to sort, so this is adequate.)
2723 */
2724 for (i = 0; i < *num_inodes; i++) {
2725 for (j = 1; j < *num_inodes; j++) {
2726 if (i_tab[j]->i_ino < i_tab[j-1]->i_ino) {
2727 temp = i_tab[j];
2728 i_tab[j] = i_tab[j-1];
2729 i_tab[j-1] = temp;
2730 }
2731 }
2732 }
2733}
2734
2735/*
2736 * xfs_rename
2737 */
2738int
2739xfs_rename(
2740 xfs_inode_t *src_dp,
2741 struct xfs_name *src_name,
2742 xfs_inode_t *src_ip,
2743 xfs_inode_t *target_dp,
2744 struct xfs_name *target_name,
2745 xfs_inode_t *target_ip)
2746{
2747 xfs_trans_t *tp = NULL;
2748 xfs_mount_t *mp = src_dp->i_mount;
2749 int new_parent; /* moving to a new dir */
2750 int src_is_directory; /* src_name is a directory */
2751 int error;
2752 xfs_bmap_free_t free_list;
2753 xfs_fsblock_t first_block;
2754 int cancel_flags;
2755 int committed;
2756 xfs_inode_t *inodes[4];
2757 int spaceres;
2758 int num_inodes;
2759
2760 trace_xfs_rename(src_dp, target_dp, src_name, target_name);
2761
2762 new_parent = (src_dp != target_dp);
2763 src_is_directory = S_ISDIR(src_ip->i_d.di_mode);
2764
2765 xfs_sort_for_rename(src_dp, target_dp, src_ip, target_ip,
2766 inodes, &num_inodes);
2767
2768 xfs_bmap_init(&free_list, &first_block);
2769 tp = xfs_trans_alloc(mp, XFS_TRANS_RENAME);
2770 cancel_flags = XFS_TRANS_RELEASE_LOG_RES;
2771 spaceres = XFS_RENAME_SPACE_RES(mp, target_name->len);
2772 error = xfs_trans_reserve(tp, &M_RES(mp)->tr_rename, spaceres, 0);
2773 if (error == ENOSPC) {
2774 spaceres = 0;
2775 error = xfs_trans_reserve(tp, &M_RES(mp)->tr_rename, 0, 0);
2776 }
2777 if (error) {
2778 xfs_trans_cancel(tp, 0);
2779 goto std_return;
2780 }
2781
2782 /*
2783 * Attach the dquots to the inodes
2784 */
2785 error = xfs_qm_vop_rename_dqattach(inodes);
2786 if (error) {
2787 xfs_trans_cancel(tp, cancel_flags);
2788 goto std_return;
2789 }
2790
2791 /*
2792 * Lock all the participating inodes. Depending upon whether
2793 * the target_name exists in the target directory, and
2794 * whether the target directory is the same as the source
2795 * directory, we can lock from 2 to 4 inodes.
2796 */
2797 xfs_lock_inodes(inodes, num_inodes, XFS_ILOCK_EXCL);
2798
2799 /*
2800 * Join all the inodes to the transaction. From this point on,
2801 * we can rely on either trans_commit or trans_cancel to unlock
2802 * them.
2803 */
2804 xfs_trans_ijoin(tp, src_dp, XFS_ILOCK_EXCL);
2805 if (new_parent)
2806 xfs_trans_ijoin(tp, target_dp, XFS_ILOCK_EXCL);
2807 xfs_trans_ijoin(tp, src_ip, XFS_ILOCK_EXCL);
2808 if (target_ip)
2809 xfs_trans_ijoin(tp, target_ip, XFS_ILOCK_EXCL);
2810
2811 /*
2812 * If we are using project inheritance, we only allow renames
2813 * into our tree when the project IDs are the same; else the
2814 * tree quota mechanism would be circumvented.
2815 */
2816 if (unlikely((target_dp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) &&
2817 (xfs_get_projid(target_dp) != xfs_get_projid(src_ip)))) {
2818 error = XFS_ERROR(EXDEV);
2819 goto error_return;
2820 }
2821
2822 /*
2823 * Set up the target.
2824 */
2825 if (target_ip == NULL) {
2826 /*
2827 * If there's no space reservation, check the entry will
2828 * fit before actually inserting it.
2829 */
2830 error = xfs_dir_canenter(tp, target_dp, target_name, spaceres);
2831 if (error)
2832 goto error_return;
2833 /*
2834 * If target does not exist and the rename crosses
2835 * directories, adjust the target directory link count
2836 * to account for the ".." reference from the new entry.
2837 */
2838 error = xfs_dir_createname(tp, target_dp, target_name,
2839 src_ip->i_ino, &first_block,
2840 &free_list, spaceres);
2841 if (error == ENOSPC)
2842 goto error_return;
2843 if (error)
2844 goto abort_return;
2845
2846 xfs_trans_ichgtime(tp, target_dp,
2847 XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2848
2849 if (new_parent && src_is_directory) {
2850 error = xfs_bumplink(tp, target_dp);
2851 if (error)
2852 goto abort_return;
2853 }
2854 } else { /* target_ip != NULL */
2855 /*
2856 * If target exists and it's a directory, check that both
2857 * target and source are directories and that target can be
2858 * destroyed, or that neither is a directory.
2859 */
2860 if (S_ISDIR(target_ip->i_d.di_mode)) {
2861 /*
2862 * Make sure target dir is empty.
2863 */
2864 if (!(xfs_dir_isempty(target_ip)) ||
2865 (target_ip->i_d.di_nlink > 2)) {
2866 error = XFS_ERROR(EEXIST);
2867 goto error_return;
2868 }
2869 }
2870
2871 /*
2872 * Link the source inode under the target name.
2873 * If the source inode is a directory and we are moving
2874 * it across directories, its ".." entry will be
2875 * inconsistent until we replace that down below.
2876 *
2877 * In case there is already an entry with the same
2878 * name at the destination directory, remove it first.
2879 */
2880 error = xfs_dir_replace(tp, target_dp, target_name,
2881 src_ip->i_ino,
2882 &first_block, &free_list, spaceres);
2883 if (error)
2884 goto abort_return;
2885
2886 xfs_trans_ichgtime(tp, target_dp,
2887 XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2888
2889 /*
2890 * Decrement the link count on the target since the target
2891 * dir no longer points to it.
2892 */
2893 error = xfs_droplink(tp, target_ip);
2894 if (error)
2895 goto abort_return;
2896
2897 if (src_is_directory) {
2898 /*
2899 * Drop the link from the old "." entry.
2900 */
2901 error = xfs_droplink(tp, target_ip);
2902 if (error)
2903 goto abort_return;
2904 }
2905 } /* target_ip != NULL */
2906
2907 /*
2908 * Remove the source.
2909 */
2910 if (new_parent && src_is_directory) {
2911 /*
2912 * Rewrite the ".." entry to point to the new
2913 * directory.
2914 */
2915 error = xfs_dir_replace(tp, src_ip, &xfs_name_dotdot,
2916 target_dp->i_ino,
2917 &first_block, &free_list, spaceres);
2918 ASSERT(error != EEXIST);
2919 if (error)
2920 goto abort_return;
2921 }
2922
2923 /*
2924 * We always want to hit the ctime on the source inode.
2925 *
2926 * This isn't strictly required by the standards since the source
2927 * inode isn't really being changed, but old unix file systems did
2928 * it and some incremental backup programs won't work without it.
2929 */
2930 xfs_trans_ichgtime(tp, src_ip, XFS_ICHGTIME_CHG);
2931 xfs_trans_log_inode(tp, src_ip, XFS_ILOG_CORE);
2932
2933 /*
2934 * Adjust the link count on src_dp. This is necessary when
2935 * renaming a directory, either within one parent when
2936 * the target existed, or across two parent directories.
2937 */
2938 if (src_is_directory && (new_parent || target_ip != NULL)) {
2939
2940 /*
2941 * Decrement link count on src_directory since the
2942 * entry that's moved no longer points to it.
2943 */
2944 error = xfs_droplink(tp, src_dp);
2945 if (error)
2946 goto abort_return;
2947 }
2948
2949 error = xfs_dir_removename(tp, src_dp, src_name, src_ip->i_ino,
2950 &first_block, &free_list, spaceres);
2951 if (error)
2952 goto abort_return;
2953
2954 xfs_trans_ichgtime(tp, src_dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2955 xfs_trans_log_inode(tp, src_dp, XFS_ILOG_CORE);
2956 if (new_parent)
2957 xfs_trans_log_inode(tp, target_dp, XFS_ILOG_CORE);
2958
2959 /*
2960 * If this is a synchronous mount, make sure that the
2961 * rename transaction goes to disk before returning to
2962 * the user.
2963 */
2964 if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC)) {
2965 xfs_trans_set_sync(tp);
2966 }
2967
2968 error = xfs_bmap_finish(&tp, &free_list, &committed);
2969 if (error) {
2970 xfs_bmap_cancel(&free_list);
2971 xfs_trans_cancel(tp, (XFS_TRANS_RELEASE_LOG_RES |
2972 XFS_TRANS_ABORT));
2973 goto std_return;
2974 }
2975
2976 /*
2977 * trans_commit will unlock src_ip, target_ip & decrement
2978 * the vnode references.
2979 */
2980 return xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
2981
2982 abort_return:
2983 cancel_flags |= XFS_TRANS_ABORT;
2984 error_return:
2985 xfs_bmap_cancel(&free_list);
2986 xfs_trans_cancel(tp, cancel_flags);
2987 std_return:
2988 return error;
2989}
2990
2991STATIC int
2992xfs_iflush_cluster(
2993 xfs_inode_t *ip,
2994 xfs_buf_t *bp)
2995{
2996 xfs_mount_t *mp = ip->i_mount;
2997 struct xfs_perag *pag;
2998 unsigned long first_index, mask;
2999 unsigned long inodes_per_cluster;
3000 int ilist_size;
3001 xfs_inode_t **ilist;
3002 xfs_inode_t *iq;
3003 int nr_found;
3004 int clcount = 0;
3005 int bufwasdelwri;
3006 int i;
3007
3008 pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));
3009
3010 inodes_per_cluster = mp->m_inode_cluster_size >> mp->m_sb.sb_inodelog;
3011 ilist_size = inodes_per_cluster * sizeof(xfs_inode_t *);
3012 ilist = kmem_alloc(ilist_size, KM_MAYFAIL|KM_NOFS);
3013 if (!ilist)
3014 goto out_put;
3015
3016 mask = ~(((mp->m_inode_cluster_size >> mp->m_sb.sb_inodelog)) - 1);
3017 first_index = XFS_INO_TO_AGINO(mp, ip->i_ino) & mask;
3018 rcu_read_lock();
3019 /* really need a gang lookup range call here */
3020 nr_found = radix_tree_gang_lookup(&pag->pag_ici_root, (void**)ilist,
3021 first_index, inodes_per_cluster);
3022 if (nr_found == 0)
3023 goto out_free;
3024
3025 for (i = 0; i < nr_found; i++) {
3026 iq = ilist[i];
3027 if (iq == ip)
3028 continue;
3029
3030 /*
3031 * because this is an RCU protected lookup, we could find a
3032 * recently freed or even reallocated inode during the lookup.
3033 * We need to check under the i_flags_lock for a valid inode
3034 * here. Skip it if it is not valid or the wrong inode.
3035 */
3036 spin_lock(&ip->i_flags_lock);
3037 if (!ip->i_ino ||
3038 (XFS_INO_TO_AGINO(mp, iq->i_ino) & mask) != first_index) {
3039 spin_unlock(&ip->i_flags_lock);
3040 continue;
3041 }
3042 spin_unlock(&ip->i_flags_lock);
3043
3044 /*
3045 * Do an un-protected check to see if the inode is dirty and
3046 * is a candidate for flushing. These checks will be repeated
3047 * later after the appropriate locks are acquired.
3048 */
3049 if (xfs_inode_clean(iq) && xfs_ipincount(iq) == 0)
3050 continue;
3051
3052 /*
3053 * Try to get locks. If any are unavailable or it is pinned,
3054 * then this inode cannot be flushed and is skipped.
3055 */
3056
3057 if (!xfs_ilock_nowait(iq, XFS_ILOCK_SHARED))
3058 continue;
3059 if (!xfs_iflock_nowait(iq)) {
3060 xfs_iunlock(iq, XFS_ILOCK_SHARED);
3061 continue;
3062 }
3063 if (xfs_ipincount(iq)) {
3064 xfs_ifunlock(iq);
3065 xfs_iunlock(iq, XFS_ILOCK_SHARED);
3066 continue;
3067 }
3068
3069 /*
3070 * arriving here means that this inode can be flushed. First
3071 * re-check that it's dirty before flushing.
3072 */
3073 if (!xfs_inode_clean(iq)) {
3074 int error;
3075 error = xfs_iflush_int(iq, bp);
3076 if (error) {
3077 xfs_iunlock(iq, XFS_ILOCK_SHARED);
3078 goto cluster_corrupt_out;
3079 }
3080 clcount++;
3081 } else {
3082 xfs_ifunlock(iq);
3083 }
3084 xfs_iunlock(iq, XFS_ILOCK_SHARED);
3085 }
3086
3087 if (clcount) {
3088 XFS_STATS_INC(xs_icluster_flushcnt);
3089 XFS_STATS_ADD(xs_icluster_flushinode, clcount);
3090 }
3091
3092out_free:
3093 rcu_read_unlock();
3094 kmem_free(ilist);
3095out_put:
3096 xfs_perag_put(pag);
3097 return 0;
3098
3099
3100cluster_corrupt_out:
3101 /*
3102 * Corruption detected in the clustering loop. Invalidate the
3103 * inode buffer and shut down the filesystem.
3104 */
3105 rcu_read_unlock();
3106 /*
3107 * Clean up the buffer. If it was delwri, just release it --
3108 * brelse can handle it with no problems. If not, shut down the
3109 * filesystem before releasing the buffer.
3110 */
3111 bufwasdelwri = (bp->b_flags & _XBF_DELWRI_Q);
3112 if (bufwasdelwri)
3113 xfs_buf_relse(bp);
3114
3115 xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
3116
3117 if (!bufwasdelwri) {
3118 /*
3119 * Just like incore_relse: if we have b_iodone functions,
3120 * mark the buffer as an error and call them. Otherwise
3121 * mark it as stale and brelse.
3122 */
3123 if (bp->b_iodone) {
3124 XFS_BUF_UNDONE(bp);
3125 xfs_buf_stale(bp);
3126 xfs_buf_ioerror(bp, EIO);
3127 xfs_buf_ioend(bp, 0);
3128 } else {
3129 xfs_buf_stale(bp);
3130 xfs_buf_relse(bp);
3131 }
3132 }
3133
3134 /*
3135 * Unlocks the flush lock
3136 */
3137 xfs_iflush_abort(iq, false);
3138 kmem_free(ilist);
3139 xfs_perag_put(pag);
3140 return XFS_ERROR(EFSCORRUPTED);
3141}
3142
3143/*
3144 * Flush dirty inode metadata into the backing buffer.
3145 *
3146 * The caller must have the inode lock and the inode flush lock held. The
3147 * inode lock will still be held upon return to the caller, and the inode
3148 * flush lock will be released after the inode has reached the disk.
3149 *
3150 * The caller must write out the buffer returned in *bpp and release it.
3151 */
3152int
3153xfs_iflush(
3154 struct xfs_inode *ip,
3155 struct xfs_buf **bpp)
3156{
3157 struct xfs_mount *mp = ip->i_mount;
3158 struct xfs_buf *bp;
3159 struct xfs_dinode *dip;
3160 int error;
3161
3162 XFS_STATS_INC(xs_iflush_count);
3163
3164 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
3165 ASSERT(xfs_isiflocked(ip));
3166 ASSERT(ip->i_d.di_format != XFS_DINODE_FMT_BTREE ||
3167 ip->i_d.di_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK));
3168
3169 *bpp = NULL;
3170
3171 xfs_iunpin_wait(ip);
3172
3173 /*
3174 * For stale inodes we cannot rely on the backing buffer remaining
3175 * stale in cache for the remaining life of the stale inode and so
3176 * xfs_imap_to_bp() below may give us a buffer that no longer contains
3177 * inodes below. We have to check this after ensuring the inode is
3178 * unpinned so that it is safe to reclaim the stale inode after the
3179 * flush call.
3180 */
3181 if (xfs_iflags_test(ip, XFS_ISTALE)) {
3182 xfs_ifunlock(ip);
3183 return 0;
3184 }
3185
3186 /*
3187 * This may have been unpinned because the filesystem is shutting
3188 * down forcibly. If that's the case we must not write this inode
3189 * to disk, because the log record didn't make it to disk.
3190 *
3191 * We also have to remove the log item from the AIL in this case,
3192 * as we wait for an empty AIL as part of the unmount process.
3193 */
3194 if (XFS_FORCED_SHUTDOWN(mp)) {
3195 error = XFS_ERROR(EIO);
3196 goto abort_out;
3197 }
3198
3199 /*
3200 * Get the buffer containing the on-disk inode.
3201 */
3202 error = xfs_imap_to_bp(mp, NULL, &ip->i_imap, &dip, &bp, XBF_TRYLOCK,
3203 0);
3204 if (error || !bp) {
3205 xfs_ifunlock(ip);
3206 return error;
3207 }
3208
3209 /*
3210 * First flush out the inode that xfs_iflush was called with.
3211 */
3212 error = xfs_iflush_int(ip, bp);
3213 if (error)
3214 goto corrupt_out;
3215
3216 /*
3217 * If the buffer is pinned then push on the log now so we won't
3218 * get stuck waiting in the write for too long.
3219 */
3220 if (xfs_buf_ispinned(bp))
3221 xfs_log_force(mp, 0);
3222
3223 /*
3224 * inode clustering:
3225 * see if other inodes can be gathered into this write
3226 */
3227 error = xfs_iflush_cluster(ip, bp);
3228 if (error)
3229 goto cluster_corrupt_out;
3230
3231 *bpp = bp;
3232 return 0;
3233
3234corrupt_out:
3235 xfs_buf_relse(bp);
3236 xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
3237cluster_corrupt_out:
3238 error = XFS_ERROR(EFSCORRUPTED);
3239abort_out:
3240 /*
3241 * Unlocks the flush lock
3242 */
3243 xfs_iflush_abort(ip, false);
3244 return error;
3245}
3246
3247STATIC int
3248xfs_iflush_int(
3249 struct xfs_inode *ip,
3250 struct xfs_buf *bp)
3251{
3252 struct xfs_inode_log_item *iip = ip->i_itemp;
3253 struct xfs_dinode *dip;
3254 struct xfs_mount *mp = ip->i_mount;
3255
3256 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
3257 ASSERT(xfs_isiflocked(ip));
3258 ASSERT(ip->i_d.di_format != XFS_DINODE_FMT_BTREE ||
3259 ip->i_d.di_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK));
3260 ASSERT(iip != NULL && iip->ili_fields != 0);
3261
3262 /* set *dip = inode's place in the buffer */
3263 dip = (xfs_dinode_t *)xfs_buf_offset(bp, ip->i_imap.im_boffset);
3264
3265 if (XFS_TEST_ERROR(dip->di_magic != cpu_to_be16(XFS_DINODE_MAGIC),
3266 mp, XFS_ERRTAG_IFLUSH_1, XFS_RANDOM_IFLUSH_1)) {
3267 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3268 "%s: Bad inode %Lu magic number 0x%x, ptr 0x%p",
3269 __func__, ip->i_ino, be16_to_cpu(dip->di_magic), dip);
3270 goto corrupt_out;
3271 }
3272 if (XFS_TEST_ERROR(ip->i_d.di_magic != XFS_DINODE_MAGIC,
3273 mp, XFS_ERRTAG_IFLUSH_2, XFS_RANDOM_IFLUSH_2)) {
3274 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3275 "%s: Bad inode %Lu, ptr 0x%p, magic number 0x%x",
3276 __func__, ip->i_ino, ip, ip->i_d.di_magic);
3277 goto corrupt_out;
3278 }
3279 if (S_ISREG(ip->i_d.di_mode)) {
3280 if (XFS_TEST_ERROR(
3281 (ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS) &&
3282 (ip->i_d.di_format != XFS_DINODE_FMT_BTREE),
3283 mp, XFS_ERRTAG_IFLUSH_3, XFS_RANDOM_IFLUSH_3)) {
3284 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3285 "%s: Bad regular inode %Lu, ptr 0x%p",
3286 __func__, ip->i_ino, ip);
3287 goto corrupt_out;
3288 }
3289 } else if (S_ISDIR(ip->i_d.di_mode)) {
3290 if (XFS_TEST_ERROR(
3291 (ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS) &&
3292 (ip->i_d.di_format != XFS_DINODE_FMT_BTREE) &&
3293 (ip->i_d.di_format != XFS_DINODE_FMT_LOCAL),
3294 mp, XFS_ERRTAG_IFLUSH_4, XFS_RANDOM_IFLUSH_4)) {
3295 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3296 "%s: Bad directory inode %Lu, ptr 0x%p",
3297 __func__, ip->i_ino, ip);
3298 goto corrupt_out;
3299 }
3300 }
3301 if (XFS_TEST_ERROR(ip->i_d.di_nextents + ip->i_d.di_anextents >
3302 ip->i_d.di_nblocks, mp, XFS_ERRTAG_IFLUSH_5,
3303 XFS_RANDOM_IFLUSH_5)) {
3304 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3305 "%s: detected corrupt incore inode %Lu, "
3306 "total extents = %d, nblocks = %Ld, ptr 0x%p",
3307 __func__, ip->i_ino,
3308 ip->i_d.di_nextents + ip->i_d.di_anextents,
3309 ip->i_d.di_nblocks, ip);
3310 goto corrupt_out;
3311 }
3312 if (XFS_TEST_ERROR(ip->i_d.di_forkoff > mp->m_sb.sb_inodesize,
3313 mp, XFS_ERRTAG_IFLUSH_6, XFS_RANDOM_IFLUSH_6)) {
3314 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3315 "%s: bad inode %Lu, forkoff 0x%x, ptr 0x%p",
3316 __func__, ip->i_ino, ip->i_d.di_forkoff, ip);
3317 goto corrupt_out;
3318 }
3319
3320 /*
3321 * Inode item log recovery for v1/v2 inodes are dependent on the
3322 * di_flushiter count for correct sequencing. We bump the flush
3323 * iteration count so we can detect flushes which postdate a log record
3324 * during recovery. This is redundant as we now log every change and
3325 * hence this can't happen but we need to still do it to ensure
3326 * backwards compatibility with old kernels that predate logging all
3327 * inode changes.
3328 */
3329 if (ip->i_d.di_version < 3)
3330 ip->i_d.di_flushiter++;
3331
3332 /*
3333 * Copy the dirty parts of the inode into the on-disk
3334 * inode. We always copy out the core of the inode,
3335 * because if the inode is dirty at all the core must
3336 * be.
3337 */
3338 xfs_dinode_to_disk(dip, &ip->i_d);
3339
3340 /* Wrap, we never let the log put out DI_MAX_FLUSH */
3341 if (ip->i_d.di_flushiter == DI_MAX_FLUSH)
3342 ip->i_d.di_flushiter = 0;
3343
3344 /*
3345 * If this is really an old format inode and the superblock version
3346 * has not been updated to support only new format inodes, then
3347 * convert back to the old inode format. If the superblock version
3348 * has been updated, then make the conversion permanent.
3349 */
3350 ASSERT(ip->i_d.di_version == 1 || xfs_sb_version_hasnlink(&mp->m_sb));
3351 if (ip->i_d.di_version == 1) {
3352 if (!xfs_sb_version_hasnlink(&mp->m_sb)) {
3353 /*
3354 * Convert it back.
3355 */
3356 ASSERT(ip->i_d.di_nlink <= XFS_MAXLINK_1);
3357 dip->di_onlink = cpu_to_be16(ip->i_d.di_nlink);
3358 } else {
3359 /*
3360 * The superblock version has already been bumped,
3361 * so just make the conversion to the new inode
3362 * format permanent.
3363 */
3364 ip->i_d.di_version = 2;
3365 dip->di_version = 2;
3366 ip->i_d.di_onlink = 0;
3367 dip->di_onlink = 0;
3368 memset(&(ip->i_d.di_pad[0]), 0, sizeof(ip->i_d.di_pad));
3369 memset(&(dip->di_pad[0]), 0,
3370 sizeof(dip->di_pad));
3371 ASSERT(xfs_get_projid(ip) == 0);
3372 }
3373 }
3374
3375 xfs_iflush_fork(ip, dip, iip, XFS_DATA_FORK, bp);
3376 if (XFS_IFORK_Q(ip))
3377 xfs_iflush_fork(ip, dip, iip, XFS_ATTR_FORK, bp);
3378 xfs_inobp_check(mp, bp);
3379
3380 /*
3381 * We've recorded everything logged in the inode, so we'd like to clear
3382 * the ili_fields bits so we don't log and flush things unnecessarily.
3383 * However, we can't stop logging all this information until the data
3384 * we've copied into the disk buffer is written to disk. If we did we
3385 * might overwrite the copy of the inode in the log with all the data
3386 * after re-logging only part of it, and in the face of a crash we
3387 * wouldn't have all the data we need to recover.
3388 *
3389 * What we do is move the bits to the ili_last_fields field. When
3390 * logging the inode, these bits are moved back to the ili_fields field.
3391 * In the xfs_iflush_done() routine we clear ili_last_fields, since we
3392 * know that the information those bits represent is permanently on
3393 * disk. As long as the flush completes before the inode is logged
3394 * again, then both ili_fields and ili_last_fields will be cleared.
3395 *
3396 * We can play with the ili_fields bits here, because the inode lock
3397 * must be held exclusively in order to set bits there and the flush
3398 * lock protects the ili_last_fields bits. Set ili_logged so the flush
3399 * done routine can tell whether or not to look in the AIL. Also, store
3400 * the current LSN of the inode so that we can tell whether the item has
3401 * moved in the AIL from xfs_iflush_done(). In order to read the lsn we
3402 * need the AIL lock, because it is a 64 bit value that cannot be read
3403 * atomically.
3404 */
3405 iip->ili_last_fields = iip->ili_fields;
3406 iip->ili_fields = 0;
3407 iip->ili_logged = 1;
3408
3409 xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn,
3410 &iip->ili_item.li_lsn);
3411
3412 /*
3413 * Attach the function xfs_iflush_done to the inode's
3414 * buffer. This will remove the inode from the AIL
3415 * and unlock the inode's flush lock when the inode is
3416 * completely written to disk.
3417 */
3418 xfs_buf_attach_iodone(bp, xfs_iflush_done, &iip->ili_item);
3419
3420 /* update the lsn in the on disk inode if required */
3421 if (ip->i_d.di_version == 3)
3422 dip->di_lsn = cpu_to_be64(iip->ili_item.li_lsn);
3423
3424 /* generate the checksum. */
3425 xfs_dinode_calc_crc(mp, dip);
3426
3427 ASSERT(bp->b_fspriv != NULL);
3428 ASSERT(bp->b_iodone != NULL);
3429 return 0;
3430
3431corrupt_out:
3432 return XFS_ERROR(EFSCORRUPTED);
3433}