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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_sb.h"
27#include "xfs_mount.h"
28#include "xfs_defer.h"
29#include "xfs_inode.h"
30#include "xfs_da_format.h"
31#include "xfs_da_btree.h"
32#include "xfs_dir2.h"
33#include "xfs_attr_sf.h"
34#include "xfs_attr.h"
35#include "xfs_trans_space.h"
36#include "xfs_trans.h"
37#include "xfs_buf_item.h"
38#include "xfs_inode_item.h"
39#include "xfs_ialloc.h"
40#include "xfs_bmap.h"
41#include "xfs_bmap_util.h"
42#include "xfs_error.h"
43#include "xfs_quota.h"
44#include "xfs_filestream.h"
45#include "xfs_cksum.h"
46#include "xfs_trace.h"
47#include "xfs_icache.h"
48#include "xfs_symlink.h"
49#include "xfs_trans_priv.h"
50#include "xfs_log.h"
51#include "xfs_bmap_btree.h"
52#include "xfs_reflink.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(struct xfs_inode *, struct xfs_buf *);
63STATIC int xfs_iunlink(struct xfs_trans *, struct xfs_inode *);
64STATIC int xfs_iunlink_remove(struct xfs_trans *, struct xfs_inode *);
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 * Helper function to extract CoW extent size hint from inode.
82 * Between the extent size hint and the CoW extent size hint, we
83 * return the greater of the two. If the value is zero (automatic),
84 * use the default size.
85 */
86xfs_extlen_t
87xfs_get_cowextsz_hint(
88 struct xfs_inode *ip)
89{
90 xfs_extlen_t a, b;
91
92 a = 0;
93 if (ip->i_d.di_flags2 & XFS_DIFLAG2_COWEXTSIZE)
94 a = ip->i_d.di_cowextsize;
95 b = xfs_get_extsz_hint(ip);
96
97 a = max(a, b);
98 if (a == 0)
99 return XFS_DEFAULT_COWEXTSZ_HINT;
100 return a;
101}
102
103/*
104 * These two are wrapper routines around the xfs_ilock() routine used to
105 * centralize some grungy code. They are used in places that wish to lock the
106 * inode solely for reading the extents. The reason these places can't just
107 * call xfs_ilock(ip, XFS_ILOCK_SHARED) is that the inode lock also guards to
108 * bringing in of the extents from disk for a file in b-tree format. If the
109 * inode is in b-tree format, then we need to lock the inode exclusively until
110 * the extents are read in. Locking it exclusively all the time would limit
111 * our parallelism unnecessarily, though. What we do instead is check to see
112 * if the extents have been read in yet, and only lock the inode exclusively
113 * if they have not.
114 *
115 * The functions return a value which should be given to the corresponding
116 * xfs_iunlock() call.
117 */
118uint
119xfs_ilock_data_map_shared(
120 struct xfs_inode *ip)
121{
122 uint lock_mode = XFS_ILOCK_SHARED;
123
124 if (ip->i_d.di_format == XFS_DINODE_FMT_BTREE &&
125 (ip->i_df.if_flags & XFS_IFEXTENTS) == 0)
126 lock_mode = XFS_ILOCK_EXCL;
127 xfs_ilock(ip, lock_mode);
128 return lock_mode;
129}
130
131uint
132xfs_ilock_attr_map_shared(
133 struct xfs_inode *ip)
134{
135 uint lock_mode = XFS_ILOCK_SHARED;
136
137 if (ip->i_d.di_aformat == XFS_DINODE_FMT_BTREE &&
138 (ip->i_afp->if_flags & XFS_IFEXTENTS) == 0)
139 lock_mode = XFS_ILOCK_EXCL;
140 xfs_ilock(ip, lock_mode);
141 return lock_mode;
142}
143
144/*
145 * In addition to i_rwsem in the VFS inode, the xfs inode contains 2
146 * multi-reader locks: i_mmap_lock and the i_lock. This routine allows
147 * various combinations of the locks to be obtained.
148 *
149 * The 3 locks should always be ordered so that the IO lock is obtained first,
150 * the mmap lock second and the ilock last in order to prevent deadlock.
151 *
152 * Basic locking order:
153 *
154 * i_rwsem -> i_mmap_lock -> page_lock -> i_ilock
155 *
156 * mmap_sem locking order:
157 *
158 * i_rwsem -> page lock -> mmap_sem
159 * mmap_sem -> i_mmap_lock -> page_lock
160 *
161 * The difference in mmap_sem locking order mean that we cannot hold the
162 * i_mmap_lock over syscall based read(2)/write(2) based IO. These IO paths can
163 * fault in pages during copy in/out (for buffered IO) or require the mmap_sem
164 * in get_user_pages() to map the user pages into the kernel address space for
165 * direct IO. Similarly the i_rwsem cannot be taken inside a page fault because
166 * page faults already hold the mmap_sem.
167 *
168 * Hence to serialise fully against both syscall and mmap based IO, we need to
169 * take both the i_rwsem and the i_mmap_lock. These locks should *only* be both
170 * taken in places where we need to invalidate the page cache in a race
171 * free manner (e.g. truncate, hole punch and other extent manipulation
172 * functions).
173 */
174void
175xfs_ilock(
176 xfs_inode_t *ip,
177 uint lock_flags)
178{
179 trace_xfs_ilock(ip, lock_flags, _RET_IP_);
180
181 /*
182 * You can't set both SHARED and EXCL for the same lock,
183 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
184 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
185 */
186 ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
187 (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
188 ASSERT((lock_flags & (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)) !=
189 (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL));
190 ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
191 (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
192 ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0);
193
194 if (lock_flags & XFS_IOLOCK_EXCL) {
195 down_write_nested(&VFS_I(ip)->i_rwsem,
196 XFS_IOLOCK_DEP(lock_flags));
197 } else if (lock_flags & XFS_IOLOCK_SHARED) {
198 down_read_nested(&VFS_I(ip)->i_rwsem,
199 XFS_IOLOCK_DEP(lock_flags));
200 }
201
202 if (lock_flags & XFS_MMAPLOCK_EXCL)
203 mrupdate_nested(&ip->i_mmaplock, XFS_MMAPLOCK_DEP(lock_flags));
204 else if (lock_flags & XFS_MMAPLOCK_SHARED)
205 mraccess_nested(&ip->i_mmaplock, XFS_MMAPLOCK_DEP(lock_flags));
206
207 if (lock_flags & XFS_ILOCK_EXCL)
208 mrupdate_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
209 else if (lock_flags & XFS_ILOCK_SHARED)
210 mraccess_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
211}
212
213/*
214 * This is just like xfs_ilock(), except that the caller
215 * is guaranteed not to sleep. It returns 1 if it gets
216 * the requested locks and 0 otherwise. If the IO lock is
217 * obtained but the inode lock cannot be, then the IO lock
218 * is dropped before returning.
219 *
220 * ip -- the inode being locked
221 * lock_flags -- this parameter indicates the inode's locks to be
222 * to be locked. See the comment for xfs_ilock() for a list
223 * of valid values.
224 */
225int
226xfs_ilock_nowait(
227 xfs_inode_t *ip,
228 uint lock_flags)
229{
230 trace_xfs_ilock_nowait(ip, lock_flags, _RET_IP_);
231
232 /*
233 * You can't set both SHARED and EXCL for the same lock,
234 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
235 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
236 */
237 ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
238 (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
239 ASSERT((lock_flags & (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)) !=
240 (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL));
241 ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
242 (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
243 ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0);
244
245 if (lock_flags & XFS_IOLOCK_EXCL) {
246 if (!down_write_trylock(&VFS_I(ip)->i_rwsem))
247 goto out;
248 } else if (lock_flags & XFS_IOLOCK_SHARED) {
249 if (!down_read_trylock(&VFS_I(ip)->i_rwsem))
250 goto out;
251 }
252
253 if (lock_flags & XFS_MMAPLOCK_EXCL) {
254 if (!mrtryupdate(&ip->i_mmaplock))
255 goto out_undo_iolock;
256 } else if (lock_flags & XFS_MMAPLOCK_SHARED) {
257 if (!mrtryaccess(&ip->i_mmaplock))
258 goto out_undo_iolock;
259 }
260
261 if (lock_flags & XFS_ILOCK_EXCL) {
262 if (!mrtryupdate(&ip->i_lock))
263 goto out_undo_mmaplock;
264 } else if (lock_flags & XFS_ILOCK_SHARED) {
265 if (!mrtryaccess(&ip->i_lock))
266 goto out_undo_mmaplock;
267 }
268 return 1;
269
270out_undo_mmaplock:
271 if (lock_flags & XFS_MMAPLOCK_EXCL)
272 mrunlock_excl(&ip->i_mmaplock);
273 else if (lock_flags & XFS_MMAPLOCK_SHARED)
274 mrunlock_shared(&ip->i_mmaplock);
275out_undo_iolock:
276 if (lock_flags & XFS_IOLOCK_EXCL)
277 up_write(&VFS_I(ip)->i_rwsem);
278 else if (lock_flags & XFS_IOLOCK_SHARED)
279 up_read(&VFS_I(ip)->i_rwsem);
280out:
281 return 0;
282}
283
284/*
285 * xfs_iunlock() is used to drop the inode locks acquired with
286 * xfs_ilock() and xfs_ilock_nowait(). The caller must pass
287 * in the flags given to xfs_ilock() or xfs_ilock_nowait() so
288 * that we know which locks to drop.
289 *
290 * ip -- the inode being unlocked
291 * lock_flags -- this parameter indicates the inode's locks to be
292 * to be unlocked. See the comment for xfs_ilock() for a list
293 * of valid values for this parameter.
294 *
295 */
296void
297xfs_iunlock(
298 xfs_inode_t *ip,
299 uint lock_flags)
300{
301 /*
302 * You can't set both SHARED and EXCL for the same lock,
303 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
304 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
305 */
306 ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
307 (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
308 ASSERT((lock_flags & (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)) !=
309 (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL));
310 ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
311 (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
312 ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0);
313 ASSERT(lock_flags != 0);
314
315 if (lock_flags & XFS_IOLOCK_EXCL)
316 up_write(&VFS_I(ip)->i_rwsem);
317 else if (lock_flags & XFS_IOLOCK_SHARED)
318 up_read(&VFS_I(ip)->i_rwsem);
319
320 if (lock_flags & XFS_MMAPLOCK_EXCL)
321 mrunlock_excl(&ip->i_mmaplock);
322 else if (lock_flags & XFS_MMAPLOCK_SHARED)
323 mrunlock_shared(&ip->i_mmaplock);
324
325 if (lock_flags & XFS_ILOCK_EXCL)
326 mrunlock_excl(&ip->i_lock);
327 else if (lock_flags & XFS_ILOCK_SHARED)
328 mrunlock_shared(&ip->i_lock);
329
330 trace_xfs_iunlock(ip, lock_flags, _RET_IP_);
331}
332
333/*
334 * give up write locks. the i/o lock cannot be held nested
335 * if it is being demoted.
336 */
337void
338xfs_ilock_demote(
339 xfs_inode_t *ip,
340 uint lock_flags)
341{
342 ASSERT(lock_flags & (XFS_IOLOCK_EXCL|XFS_MMAPLOCK_EXCL|XFS_ILOCK_EXCL));
343 ASSERT((lock_flags &
344 ~(XFS_IOLOCK_EXCL|XFS_MMAPLOCK_EXCL|XFS_ILOCK_EXCL)) == 0);
345
346 if (lock_flags & XFS_ILOCK_EXCL)
347 mrdemote(&ip->i_lock);
348 if (lock_flags & XFS_MMAPLOCK_EXCL)
349 mrdemote(&ip->i_mmaplock);
350 if (lock_flags & XFS_IOLOCK_EXCL)
351 downgrade_write(&VFS_I(ip)->i_rwsem);
352
353 trace_xfs_ilock_demote(ip, lock_flags, _RET_IP_);
354}
355
356#if defined(DEBUG) || defined(XFS_WARN)
357int
358xfs_isilocked(
359 xfs_inode_t *ip,
360 uint lock_flags)
361{
362 if (lock_flags & (XFS_ILOCK_EXCL|XFS_ILOCK_SHARED)) {
363 if (!(lock_flags & XFS_ILOCK_SHARED))
364 return !!ip->i_lock.mr_writer;
365 return rwsem_is_locked(&ip->i_lock.mr_lock);
366 }
367
368 if (lock_flags & (XFS_MMAPLOCK_EXCL|XFS_MMAPLOCK_SHARED)) {
369 if (!(lock_flags & XFS_MMAPLOCK_SHARED))
370 return !!ip->i_mmaplock.mr_writer;
371 return rwsem_is_locked(&ip->i_mmaplock.mr_lock);
372 }
373
374 if (lock_flags & (XFS_IOLOCK_EXCL|XFS_IOLOCK_SHARED)) {
375 if (!(lock_flags & XFS_IOLOCK_SHARED))
376 return !debug_locks ||
377 lockdep_is_held_type(&VFS_I(ip)->i_rwsem, 0);
378 return rwsem_is_locked(&VFS_I(ip)->i_rwsem);
379 }
380
381 ASSERT(0);
382 return 0;
383}
384#endif
385
386#ifdef DEBUG
387int xfs_locked_n;
388int xfs_small_retries;
389int xfs_middle_retries;
390int xfs_lots_retries;
391int xfs_lock_delays;
392#endif
393
394/*
395 * xfs_lockdep_subclass_ok() is only used in an ASSERT, so is only called when
396 * DEBUG or XFS_WARN is set. And MAX_LOCKDEP_SUBCLASSES is then only defined
397 * when CONFIG_LOCKDEP is set. Hence the complex define below to avoid build
398 * errors and warnings.
399 */
400#if (defined(DEBUG) || defined(XFS_WARN)) && defined(CONFIG_LOCKDEP)
401static bool
402xfs_lockdep_subclass_ok(
403 int subclass)
404{
405 return subclass < MAX_LOCKDEP_SUBCLASSES;
406}
407#else
408#define xfs_lockdep_subclass_ok(subclass) (true)
409#endif
410
411/*
412 * Bump the subclass so xfs_lock_inodes() acquires each lock with a different
413 * value. This can be called for any type of inode lock combination, including
414 * parent locking. Care must be taken to ensure we don't overrun the subclass
415 * storage fields in the class mask we build.
416 */
417static inline int
418xfs_lock_inumorder(int lock_mode, int subclass)
419{
420 int class = 0;
421
422 ASSERT(!(lock_mode & (XFS_ILOCK_PARENT | XFS_ILOCK_RTBITMAP |
423 XFS_ILOCK_RTSUM)));
424 ASSERT(xfs_lockdep_subclass_ok(subclass));
425
426 if (lock_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)) {
427 ASSERT(subclass <= XFS_IOLOCK_MAX_SUBCLASS);
428 class += subclass << XFS_IOLOCK_SHIFT;
429 }
430
431 if (lock_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) {
432 ASSERT(subclass <= XFS_MMAPLOCK_MAX_SUBCLASS);
433 class += subclass << XFS_MMAPLOCK_SHIFT;
434 }
435
436 if (lock_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)) {
437 ASSERT(subclass <= XFS_ILOCK_MAX_SUBCLASS);
438 class += subclass << XFS_ILOCK_SHIFT;
439 }
440
441 return (lock_mode & ~XFS_LOCK_SUBCLASS_MASK) | class;
442}
443
444/*
445 * The following routine will lock n inodes in exclusive mode. We assume the
446 * caller calls us with the inodes in i_ino order.
447 *
448 * We need to detect deadlock where an inode that we lock is in the AIL and we
449 * start waiting for another inode that is locked by a thread in a long running
450 * transaction (such as truncate). This can result in deadlock since the long
451 * running trans might need to wait for the inode we just locked in order to
452 * push the tail and free space in the log.
453 *
454 * xfs_lock_inodes() can only be used to lock one type of lock at a time -
455 * the iolock, the mmaplock or the ilock, but not more than one at a time. If we
456 * lock more than one at a time, lockdep will report false positives saying we
457 * have violated locking orders.
458 */
459static void
460xfs_lock_inodes(
461 xfs_inode_t **ips,
462 int inodes,
463 uint lock_mode)
464{
465 int attempts = 0, i, j, try_lock;
466 xfs_log_item_t *lp;
467
468 /*
469 * Currently supports between 2 and 5 inodes with exclusive locking. We
470 * support an arbitrary depth of locking here, but absolute limits on
471 * inodes depend on the the type of locking and the limits placed by
472 * lockdep annotations in xfs_lock_inumorder. These are all checked by
473 * the asserts.
474 */
475 ASSERT(ips && inodes >= 2 && inodes <= 5);
476 ASSERT(lock_mode & (XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL |
477 XFS_ILOCK_EXCL));
478 ASSERT(!(lock_mode & (XFS_IOLOCK_SHARED | XFS_MMAPLOCK_SHARED |
479 XFS_ILOCK_SHARED)));
480 ASSERT(!(lock_mode & XFS_MMAPLOCK_EXCL) ||
481 inodes <= XFS_MMAPLOCK_MAX_SUBCLASS + 1);
482 ASSERT(!(lock_mode & XFS_ILOCK_EXCL) ||
483 inodes <= XFS_ILOCK_MAX_SUBCLASS + 1);
484
485 if (lock_mode & XFS_IOLOCK_EXCL) {
486 ASSERT(!(lock_mode & (XFS_MMAPLOCK_EXCL | XFS_ILOCK_EXCL)));
487 } else if (lock_mode & XFS_MMAPLOCK_EXCL)
488 ASSERT(!(lock_mode & XFS_ILOCK_EXCL));
489
490 try_lock = 0;
491 i = 0;
492again:
493 for (; i < inodes; i++) {
494 ASSERT(ips[i]);
495
496 if (i && (ips[i] == ips[i - 1])) /* Already locked */
497 continue;
498
499 /*
500 * If try_lock is not set yet, make sure all locked inodes are
501 * not in the AIL. If any are, set try_lock to be used later.
502 */
503 if (!try_lock) {
504 for (j = (i - 1); j >= 0 && !try_lock; j--) {
505 lp = (xfs_log_item_t *)ips[j]->i_itemp;
506 if (lp && (lp->li_flags & XFS_LI_IN_AIL))
507 try_lock++;
508 }
509 }
510
511 /*
512 * If any of the previous locks we have locked is in the AIL,
513 * we must TRY to get the second and subsequent locks. If
514 * we can't get any, we must release all we have
515 * and try again.
516 */
517 if (!try_lock) {
518 xfs_ilock(ips[i], xfs_lock_inumorder(lock_mode, i));
519 continue;
520 }
521
522 /* try_lock means we have an inode locked that is in the AIL. */
523 ASSERT(i != 0);
524 if (xfs_ilock_nowait(ips[i], xfs_lock_inumorder(lock_mode, i)))
525 continue;
526
527 /*
528 * Unlock all previous guys and try again. xfs_iunlock will try
529 * to push the tail if the inode is in the AIL.
530 */
531 attempts++;
532 for (j = i - 1; j >= 0; j--) {
533 /*
534 * Check to see if we've already unlocked this one. Not
535 * the first one going back, and the inode ptr is the
536 * same.
537 */
538 if (j != (i - 1) && ips[j] == ips[j + 1])
539 continue;
540
541 xfs_iunlock(ips[j], lock_mode);
542 }
543
544 if ((attempts % 5) == 0) {
545 delay(1); /* Don't just spin the CPU */
546#ifdef DEBUG
547 xfs_lock_delays++;
548#endif
549 }
550 i = 0;
551 try_lock = 0;
552 goto again;
553 }
554
555#ifdef DEBUG
556 if (attempts) {
557 if (attempts < 5) xfs_small_retries++;
558 else if (attempts < 100) xfs_middle_retries++;
559 else xfs_lots_retries++;
560 } else {
561 xfs_locked_n++;
562 }
563#endif
564}
565
566/*
567 * xfs_lock_two_inodes() can only be used to lock one type of lock at a time -
568 * the iolock, the mmaplock or the ilock, but not more than one at a time. If we
569 * lock more than one at a time, lockdep will report false positives saying we
570 * have violated locking orders.
571 */
572void
573xfs_lock_two_inodes(
574 xfs_inode_t *ip0,
575 xfs_inode_t *ip1,
576 uint lock_mode)
577{
578 xfs_inode_t *temp;
579 int attempts = 0;
580 xfs_log_item_t *lp;
581
582 ASSERT(!(lock_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)));
583 if (lock_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL))
584 ASSERT(!(lock_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)));
585
586 ASSERT(ip0->i_ino != ip1->i_ino);
587
588 if (ip0->i_ino > ip1->i_ino) {
589 temp = ip0;
590 ip0 = ip1;
591 ip1 = temp;
592 }
593
594 again:
595 xfs_ilock(ip0, xfs_lock_inumorder(lock_mode, 0));
596
597 /*
598 * If the first lock we have locked is in the AIL, we must TRY to get
599 * the second lock. If we can't get it, we must release the first one
600 * and try again.
601 */
602 lp = (xfs_log_item_t *)ip0->i_itemp;
603 if (lp && (lp->li_flags & XFS_LI_IN_AIL)) {
604 if (!xfs_ilock_nowait(ip1, xfs_lock_inumorder(lock_mode, 1))) {
605 xfs_iunlock(ip0, lock_mode);
606 if ((++attempts % 5) == 0)
607 delay(1); /* Don't just spin the CPU */
608 goto again;
609 }
610 } else {
611 xfs_ilock(ip1, xfs_lock_inumorder(lock_mode, 1));
612 }
613}
614
615
616void
617__xfs_iflock(
618 struct xfs_inode *ip)
619{
620 wait_queue_head_t *wq = bit_waitqueue(&ip->i_flags, __XFS_IFLOCK_BIT);
621 DEFINE_WAIT_BIT(wait, &ip->i_flags, __XFS_IFLOCK_BIT);
622
623 do {
624 prepare_to_wait_exclusive(wq, &wait.wait, TASK_UNINTERRUPTIBLE);
625 if (xfs_isiflocked(ip))
626 io_schedule();
627 } while (!xfs_iflock_nowait(ip));
628
629 finish_wait(wq, &wait.wait);
630}
631
632STATIC uint
633_xfs_dic2xflags(
634 __uint16_t di_flags,
635 uint64_t di_flags2,
636 bool has_attr)
637{
638 uint flags = 0;
639
640 if (di_flags & XFS_DIFLAG_ANY) {
641 if (di_flags & XFS_DIFLAG_REALTIME)
642 flags |= FS_XFLAG_REALTIME;
643 if (di_flags & XFS_DIFLAG_PREALLOC)
644 flags |= FS_XFLAG_PREALLOC;
645 if (di_flags & XFS_DIFLAG_IMMUTABLE)
646 flags |= FS_XFLAG_IMMUTABLE;
647 if (di_flags & XFS_DIFLAG_APPEND)
648 flags |= FS_XFLAG_APPEND;
649 if (di_flags & XFS_DIFLAG_SYNC)
650 flags |= FS_XFLAG_SYNC;
651 if (di_flags & XFS_DIFLAG_NOATIME)
652 flags |= FS_XFLAG_NOATIME;
653 if (di_flags & XFS_DIFLAG_NODUMP)
654 flags |= FS_XFLAG_NODUMP;
655 if (di_flags & XFS_DIFLAG_RTINHERIT)
656 flags |= FS_XFLAG_RTINHERIT;
657 if (di_flags & XFS_DIFLAG_PROJINHERIT)
658 flags |= FS_XFLAG_PROJINHERIT;
659 if (di_flags & XFS_DIFLAG_NOSYMLINKS)
660 flags |= FS_XFLAG_NOSYMLINKS;
661 if (di_flags & XFS_DIFLAG_EXTSIZE)
662 flags |= FS_XFLAG_EXTSIZE;
663 if (di_flags & XFS_DIFLAG_EXTSZINHERIT)
664 flags |= FS_XFLAG_EXTSZINHERIT;
665 if (di_flags & XFS_DIFLAG_NODEFRAG)
666 flags |= FS_XFLAG_NODEFRAG;
667 if (di_flags & XFS_DIFLAG_FILESTREAM)
668 flags |= FS_XFLAG_FILESTREAM;
669 }
670
671 if (di_flags2 & XFS_DIFLAG2_ANY) {
672 if (di_flags2 & XFS_DIFLAG2_DAX)
673 flags |= FS_XFLAG_DAX;
674 if (di_flags2 & XFS_DIFLAG2_COWEXTSIZE)
675 flags |= FS_XFLAG_COWEXTSIZE;
676 }
677
678 if (has_attr)
679 flags |= FS_XFLAG_HASATTR;
680
681 return flags;
682}
683
684uint
685xfs_ip2xflags(
686 struct xfs_inode *ip)
687{
688 struct xfs_icdinode *dic = &ip->i_d;
689
690 return _xfs_dic2xflags(dic->di_flags, dic->di_flags2, XFS_IFORK_Q(ip));
691}
692
693/*
694 * Lookups up an inode from "name". If ci_name is not NULL, then a CI match
695 * is allowed, otherwise it has to be an exact match. If a CI match is found,
696 * ci_name->name will point to a the actual name (caller must free) or
697 * will be set to NULL if an exact match is found.
698 */
699int
700xfs_lookup(
701 xfs_inode_t *dp,
702 struct xfs_name *name,
703 xfs_inode_t **ipp,
704 struct xfs_name *ci_name)
705{
706 xfs_ino_t inum;
707 int error;
708
709 trace_xfs_lookup(dp, name);
710
711 if (XFS_FORCED_SHUTDOWN(dp->i_mount))
712 return -EIO;
713
714 error = xfs_dir_lookup(NULL, dp, name, &inum, ci_name);
715 if (error)
716 goto out_unlock;
717
718 error = xfs_iget(dp->i_mount, NULL, inum, 0, 0, ipp);
719 if (error)
720 goto out_free_name;
721
722 return 0;
723
724out_free_name:
725 if (ci_name)
726 kmem_free(ci_name->name);
727out_unlock:
728 *ipp = NULL;
729 return error;
730}
731
732/*
733 * Allocate an inode on disk and return a copy of its in-core version.
734 * The in-core inode is locked exclusively. Set mode, nlink, and rdev
735 * appropriately within the inode. The uid and gid for the inode are
736 * set according to the contents of the given cred structure.
737 *
738 * Use xfs_dialloc() to allocate the on-disk inode. If xfs_dialloc()
739 * has a free inode available, call xfs_iget() to obtain the in-core
740 * version of the allocated inode. Finally, fill in the inode and
741 * log its initial contents. In this case, ialloc_context would be
742 * set to NULL.
743 *
744 * If xfs_dialloc() does not have an available inode, it will replenish
745 * its supply by doing an allocation. Since we can only do one
746 * allocation within a transaction without deadlocks, we must commit
747 * the current transaction before returning the inode itself.
748 * In this case, therefore, we will set ialloc_context and return.
749 * The caller should then commit the current transaction, start a new
750 * transaction, and call xfs_ialloc() again to actually get the inode.
751 *
752 * To ensure that some other process does not grab the inode that
753 * was allocated during the first call to xfs_ialloc(), this routine
754 * also returns the [locked] bp pointing to the head of the freelist
755 * as ialloc_context. The caller should hold this buffer across
756 * the commit and pass it back into this routine on the second call.
757 *
758 * If we are allocating quota inodes, we do not have a parent inode
759 * to attach to or associate with (i.e. pip == NULL) because they
760 * are not linked into the directory structure - they are attached
761 * directly to the superblock - and so have no parent.
762 */
763static int
764xfs_ialloc(
765 xfs_trans_t *tp,
766 xfs_inode_t *pip,
767 umode_t mode,
768 xfs_nlink_t nlink,
769 xfs_dev_t rdev,
770 prid_t prid,
771 int okalloc,
772 xfs_buf_t **ialloc_context,
773 xfs_inode_t **ipp)
774{
775 struct xfs_mount *mp = tp->t_mountp;
776 xfs_ino_t ino;
777 xfs_inode_t *ip;
778 uint flags;
779 int error;
780 struct timespec tv;
781 struct inode *inode;
782
783 /*
784 * Call the space management code to pick
785 * the on-disk inode to be allocated.
786 */
787 error = xfs_dialloc(tp, pip ? pip->i_ino : 0, mode, okalloc,
788 ialloc_context, &ino);
789 if (error)
790 return error;
791 if (*ialloc_context || ino == NULLFSINO) {
792 *ipp = NULL;
793 return 0;
794 }
795 ASSERT(*ialloc_context == NULL);
796
797 /*
798 * Get the in-core inode with the lock held exclusively.
799 * This is because we're setting fields here we need
800 * to prevent others from looking at until we're done.
801 */
802 error = xfs_iget(mp, tp, ino, XFS_IGET_CREATE,
803 XFS_ILOCK_EXCL, &ip);
804 if (error)
805 return error;
806 ASSERT(ip != NULL);
807 inode = VFS_I(ip);
808
809 /*
810 * We always convert v1 inodes to v2 now - we only support filesystems
811 * with >= v2 inode capability, so there is no reason for ever leaving
812 * an inode in v1 format.
813 */
814 if (ip->i_d.di_version == 1)
815 ip->i_d.di_version = 2;
816
817 inode->i_mode = mode;
818 set_nlink(inode, nlink);
819 ip->i_d.di_uid = xfs_kuid_to_uid(current_fsuid());
820 ip->i_d.di_gid = xfs_kgid_to_gid(current_fsgid());
821 xfs_set_projid(ip, prid);
822
823 if (pip && XFS_INHERIT_GID(pip)) {
824 ip->i_d.di_gid = pip->i_d.di_gid;
825 if ((VFS_I(pip)->i_mode & S_ISGID) && S_ISDIR(mode))
826 inode->i_mode |= S_ISGID;
827 }
828
829 /*
830 * If the group ID of the new file does not match the effective group
831 * ID or one of the supplementary group IDs, the S_ISGID bit is cleared
832 * (and only if the irix_sgid_inherit compatibility variable is set).
833 */
834 if ((irix_sgid_inherit) &&
835 (inode->i_mode & S_ISGID) &&
836 (!in_group_p(xfs_gid_to_kgid(ip->i_d.di_gid))))
837 inode->i_mode &= ~S_ISGID;
838
839 ip->i_d.di_size = 0;
840 ip->i_d.di_nextents = 0;
841 ASSERT(ip->i_d.di_nblocks == 0);
842
843 tv = current_time(inode);
844 inode->i_mtime = tv;
845 inode->i_atime = tv;
846 inode->i_ctime = tv;
847
848 ip->i_d.di_extsize = 0;
849 ip->i_d.di_dmevmask = 0;
850 ip->i_d.di_dmstate = 0;
851 ip->i_d.di_flags = 0;
852
853 if (ip->i_d.di_version == 3) {
854 inode->i_version = 1;
855 ip->i_d.di_flags2 = 0;
856 ip->i_d.di_cowextsize = 0;
857 ip->i_d.di_crtime.t_sec = (__int32_t)tv.tv_sec;
858 ip->i_d.di_crtime.t_nsec = (__int32_t)tv.tv_nsec;
859 }
860
861
862 flags = XFS_ILOG_CORE;
863 switch (mode & S_IFMT) {
864 case S_IFIFO:
865 case S_IFCHR:
866 case S_IFBLK:
867 case S_IFSOCK:
868 ip->i_d.di_format = XFS_DINODE_FMT_DEV;
869 ip->i_df.if_u2.if_rdev = rdev;
870 ip->i_df.if_flags = 0;
871 flags |= XFS_ILOG_DEV;
872 break;
873 case S_IFREG:
874 case S_IFDIR:
875 if (pip && (pip->i_d.di_flags & XFS_DIFLAG_ANY)) {
876 uint64_t di_flags2 = 0;
877 uint di_flags = 0;
878
879 if (S_ISDIR(mode)) {
880 if (pip->i_d.di_flags & XFS_DIFLAG_RTINHERIT)
881 di_flags |= XFS_DIFLAG_RTINHERIT;
882 if (pip->i_d.di_flags & XFS_DIFLAG_EXTSZINHERIT) {
883 di_flags |= XFS_DIFLAG_EXTSZINHERIT;
884 ip->i_d.di_extsize = pip->i_d.di_extsize;
885 }
886 if (pip->i_d.di_flags & XFS_DIFLAG_PROJINHERIT)
887 di_flags |= XFS_DIFLAG_PROJINHERIT;
888 } else if (S_ISREG(mode)) {
889 if (pip->i_d.di_flags & XFS_DIFLAG_RTINHERIT)
890 di_flags |= XFS_DIFLAG_REALTIME;
891 if (pip->i_d.di_flags & XFS_DIFLAG_EXTSZINHERIT) {
892 di_flags |= XFS_DIFLAG_EXTSIZE;
893 ip->i_d.di_extsize = pip->i_d.di_extsize;
894 }
895 }
896 if ((pip->i_d.di_flags & XFS_DIFLAG_NOATIME) &&
897 xfs_inherit_noatime)
898 di_flags |= XFS_DIFLAG_NOATIME;
899 if ((pip->i_d.di_flags & XFS_DIFLAG_NODUMP) &&
900 xfs_inherit_nodump)
901 di_flags |= XFS_DIFLAG_NODUMP;
902 if ((pip->i_d.di_flags & XFS_DIFLAG_SYNC) &&
903 xfs_inherit_sync)
904 di_flags |= XFS_DIFLAG_SYNC;
905 if ((pip->i_d.di_flags & XFS_DIFLAG_NOSYMLINKS) &&
906 xfs_inherit_nosymlinks)
907 di_flags |= XFS_DIFLAG_NOSYMLINKS;
908 if ((pip->i_d.di_flags & XFS_DIFLAG_NODEFRAG) &&
909 xfs_inherit_nodefrag)
910 di_flags |= XFS_DIFLAG_NODEFRAG;
911 if (pip->i_d.di_flags & XFS_DIFLAG_FILESTREAM)
912 di_flags |= XFS_DIFLAG_FILESTREAM;
913 if (pip->i_d.di_flags2 & XFS_DIFLAG2_DAX)
914 di_flags2 |= XFS_DIFLAG2_DAX;
915
916 ip->i_d.di_flags |= di_flags;
917 ip->i_d.di_flags2 |= di_flags2;
918 }
919 if (pip &&
920 (pip->i_d.di_flags2 & XFS_DIFLAG2_ANY) &&
921 pip->i_d.di_version == 3 &&
922 ip->i_d.di_version == 3) {
923 if (pip->i_d.di_flags2 & XFS_DIFLAG2_COWEXTSIZE) {
924 ip->i_d.di_flags2 |= XFS_DIFLAG2_COWEXTSIZE;
925 ip->i_d.di_cowextsize = pip->i_d.di_cowextsize;
926 }
927 }
928 /* FALLTHROUGH */
929 case S_IFLNK:
930 ip->i_d.di_format = XFS_DINODE_FMT_EXTENTS;
931 ip->i_df.if_flags = XFS_IFEXTENTS;
932 ip->i_df.if_bytes = ip->i_df.if_real_bytes = 0;
933 ip->i_df.if_u1.if_extents = NULL;
934 break;
935 default:
936 ASSERT(0);
937 }
938 /*
939 * Attribute fork settings for new inode.
940 */
941 ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;
942 ip->i_d.di_anextents = 0;
943
944 /*
945 * Log the new values stuffed into the inode.
946 */
947 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
948 xfs_trans_log_inode(tp, ip, flags);
949
950 /* now that we have an i_mode we can setup the inode structure */
951 xfs_setup_inode(ip);
952
953 *ipp = ip;
954 return 0;
955}
956
957/*
958 * Allocates a new inode from disk and return a pointer to the
959 * incore copy. This routine will internally commit the current
960 * transaction and allocate a new one if the Space Manager needed
961 * to do an allocation to replenish the inode free-list.
962 *
963 * This routine is designed to be called from xfs_create and
964 * xfs_create_dir.
965 *
966 */
967int
968xfs_dir_ialloc(
969 xfs_trans_t **tpp, /* input: current transaction;
970 output: may be a new transaction. */
971 xfs_inode_t *dp, /* directory within whose allocate
972 the inode. */
973 umode_t mode,
974 xfs_nlink_t nlink,
975 xfs_dev_t rdev,
976 prid_t prid, /* project id */
977 int okalloc, /* ok to allocate new space */
978 xfs_inode_t **ipp, /* pointer to inode; it will be
979 locked. */
980 int *committed)
981
982{
983 xfs_trans_t *tp;
984 xfs_inode_t *ip;
985 xfs_buf_t *ialloc_context = NULL;
986 int code;
987 void *dqinfo;
988 uint tflags;
989
990 tp = *tpp;
991 ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
992
993 /*
994 * xfs_ialloc will return a pointer to an incore inode if
995 * the Space Manager has an available inode on the free
996 * list. Otherwise, it will do an allocation and replenish
997 * the freelist. Since we can only do one allocation per
998 * transaction without deadlocks, we will need to commit the
999 * current transaction and start a new one. We will then
1000 * need to call xfs_ialloc again to get the inode.
1001 *
1002 * If xfs_ialloc did an allocation to replenish the freelist,
1003 * it returns the bp containing the head of the freelist as
1004 * ialloc_context. We will hold a lock on it across the
1005 * transaction commit so that no other process can steal
1006 * the inode(s) that we've just allocated.
1007 */
1008 code = xfs_ialloc(tp, dp, mode, nlink, rdev, prid, okalloc,
1009 &ialloc_context, &ip);
1010
1011 /*
1012 * Return an error if we were unable to allocate a new inode.
1013 * This should only happen if we run out of space on disk or
1014 * encounter a disk error.
1015 */
1016 if (code) {
1017 *ipp = NULL;
1018 return code;
1019 }
1020 if (!ialloc_context && !ip) {
1021 *ipp = NULL;
1022 return -ENOSPC;
1023 }
1024
1025 /*
1026 * If the AGI buffer is non-NULL, then we were unable to get an
1027 * inode in one operation. We need to commit the current
1028 * transaction and call xfs_ialloc() again. It is guaranteed
1029 * to succeed the second time.
1030 */
1031 if (ialloc_context) {
1032 /*
1033 * Normally, xfs_trans_commit releases all the locks.
1034 * We call bhold to hang on to the ialloc_context across
1035 * the commit. Holding this buffer prevents any other
1036 * processes from doing any allocations in this
1037 * allocation group.
1038 */
1039 xfs_trans_bhold(tp, ialloc_context);
1040
1041 /*
1042 * We want the quota changes to be associated with the next
1043 * transaction, NOT this one. So, detach the dqinfo from this
1044 * and attach it to the next transaction.
1045 */
1046 dqinfo = NULL;
1047 tflags = 0;
1048 if (tp->t_dqinfo) {
1049 dqinfo = (void *)tp->t_dqinfo;
1050 tp->t_dqinfo = NULL;
1051 tflags = tp->t_flags & XFS_TRANS_DQ_DIRTY;
1052 tp->t_flags &= ~(XFS_TRANS_DQ_DIRTY);
1053 }
1054
1055 code = xfs_trans_roll(&tp, NULL);
1056 if (committed != NULL)
1057 *committed = 1;
1058
1059 /*
1060 * Re-attach the quota info that we detached from prev trx.
1061 */
1062 if (dqinfo) {
1063 tp->t_dqinfo = dqinfo;
1064 tp->t_flags |= tflags;
1065 }
1066
1067 if (code) {
1068 xfs_buf_relse(ialloc_context);
1069 *tpp = tp;
1070 *ipp = NULL;
1071 return code;
1072 }
1073 xfs_trans_bjoin(tp, ialloc_context);
1074
1075 /*
1076 * Call ialloc again. Since we've locked out all
1077 * other allocations in this allocation group,
1078 * this call should always succeed.
1079 */
1080 code = xfs_ialloc(tp, dp, mode, nlink, rdev, prid,
1081 okalloc, &ialloc_context, &ip);
1082
1083 /*
1084 * If we get an error at this point, return to the caller
1085 * so that the current transaction can be aborted.
1086 */
1087 if (code) {
1088 *tpp = tp;
1089 *ipp = NULL;
1090 return code;
1091 }
1092 ASSERT(!ialloc_context && ip);
1093
1094 } else {
1095 if (committed != NULL)
1096 *committed = 0;
1097 }
1098
1099 *ipp = ip;
1100 *tpp = tp;
1101
1102 return 0;
1103}
1104
1105/*
1106 * Decrement the link count on an inode & log the change. If this causes the
1107 * link count to go to zero, move the inode to AGI unlinked list so that it can
1108 * be freed when the last active reference goes away via xfs_inactive().
1109 */
1110static int /* error */
1111xfs_droplink(
1112 xfs_trans_t *tp,
1113 xfs_inode_t *ip)
1114{
1115 xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
1116
1117 drop_nlink(VFS_I(ip));
1118 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1119
1120 if (VFS_I(ip)->i_nlink)
1121 return 0;
1122
1123 return xfs_iunlink(tp, ip);
1124}
1125
1126/*
1127 * Increment the link count on an inode & log the change.
1128 */
1129static int
1130xfs_bumplink(
1131 xfs_trans_t *tp,
1132 xfs_inode_t *ip)
1133{
1134 xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
1135
1136 ASSERT(ip->i_d.di_version > 1);
1137 inc_nlink(VFS_I(ip));
1138 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1139 return 0;
1140}
1141
1142int
1143xfs_create(
1144 xfs_inode_t *dp,
1145 struct xfs_name *name,
1146 umode_t mode,
1147 xfs_dev_t rdev,
1148 xfs_inode_t **ipp)
1149{
1150 int is_dir = S_ISDIR(mode);
1151 struct xfs_mount *mp = dp->i_mount;
1152 struct xfs_inode *ip = NULL;
1153 struct xfs_trans *tp = NULL;
1154 int error;
1155 struct xfs_defer_ops dfops;
1156 xfs_fsblock_t first_block;
1157 bool unlock_dp_on_error = false;
1158 prid_t prid;
1159 struct xfs_dquot *udqp = NULL;
1160 struct xfs_dquot *gdqp = NULL;
1161 struct xfs_dquot *pdqp = NULL;
1162 struct xfs_trans_res *tres;
1163 uint resblks;
1164
1165 trace_xfs_create(dp, name);
1166
1167 if (XFS_FORCED_SHUTDOWN(mp))
1168 return -EIO;
1169
1170 prid = xfs_get_initial_prid(dp);
1171
1172 /*
1173 * Make sure that we have allocated dquot(s) on disk.
1174 */
1175 error = xfs_qm_vop_dqalloc(dp, xfs_kuid_to_uid(current_fsuid()),
1176 xfs_kgid_to_gid(current_fsgid()), prid,
1177 XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
1178 &udqp, &gdqp, &pdqp);
1179 if (error)
1180 return error;
1181
1182 if (is_dir) {
1183 rdev = 0;
1184 resblks = XFS_MKDIR_SPACE_RES(mp, name->len);
1185 tres = &M_RES(mp)->tr_mkdir;
1186 } else {
1187 resblks = XFS_CREATE_SPACE_RES(mp, name->len);
1188 tres = &M_RES(mp)->tr_create;
1189 }
1190
1191 /*
1192 * Initially assume that the file does not exist and
1193 * reserve the resources for that case. If that is not
1194 * the case we'll drop the one we have and get a more
1195 * appropriate transaction later.
1196 */
1197 error = xfs_trans_alloc(mp, tres, resblks, 0, 0, &tp);
1198 if (error == -ENOSPC) {
1199 /* flush outstanding delalloc blocks and retry */
1200 xfs_flush_inodes(mp);
1201 error = xfs_trans_alloc(mp, tres, resblks, 0, 0, &tp);
1202 }
1203 if (error == -ENOSPC) {
1204 /* No space at all so try a "no-allocation" reservation */
1205 resblks = 0;
1206 error = xfs_trans_alloc(mp, tres, 0, 0, 0, &tp);
1207 }
1208 if (error)
1209 goto out_release_inode;
1210
1211 xfs_ilock(dp, XFS_ILOCK_EXCL | XFS_ILOCK_PARENT);
1212 unlock_dp_on_error = true;
1213
1214 xfs_defer_init(&dfops, &first_block);
1215
1216 /*
1217 * Reserve disk quota and the inode.
1218 */
1219 error = xfs_trans_reserve_quota(tp, mp, udqp, gdqp,
1220 pdqp, resblks, 1, 0);
1221 if (error)
1222 goto out_trans_cancel;
1223
1224 if (!resblks) {
1225 error = xfs_dir_canenter(tp, dp, name);
1226 if (error)
1227 goto out_trans_cancel;
1228 }
1229
1230 /*
1231 * A newly created regular or special file just has one directory
1232 * entry pointing to them, but a directory also the "." entry
1233 * pointing to itself.
1234 */
1235 error = xfs_dir_ialloc(&tp, dp, mode, is_dir ? 2 : 1, rdev,
1236 prid, resblks > 0, &ip, NULL);
1237 if (error)
1238 goto out_trans_cancel;
1239
1240 /*
1241 * Now we join the directory inode to the transaction. We do not do it
1242 * earlier because xfs_dir_ialloc might commit the previous transaction
1243 * (and release all the locks). An error from here on will result in
1244 * the transaction cancel unlocking dp so don't do it explicitly in the
1245 * error path.
1246 */
1247 xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
1248 unlock_dp_on_error = false;
1249
1250 error = xfs_dir_createname(tp, dp, name, ip->i_ino,
1251 &first_block, &dfops, resblks ?
1252 resblks - XFS_IALLOC_SPACE_RES(mp) : 0);
1253 if (error) {
1254 ASSERT(error != -ENOSPC);
1255 goto out_trans_cancel;
1256 }
1257 xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1258 xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
1259
1260 if (is_dir) {
1261 error = xfs_dir_init(tp, ip, dp);
1262 if (error)
1263 goto out_bmap_cancel;
1264
1265 error = xfs_bumplink(tp, dp);
1266 if (error)
1267 goto out_bmap_cancel;
1268 }
1269
1270 /*
1271 * If this is a synchronous mount, make sure that the
1272 * create transaction goes to disk before returning to
1273 * the user.
1274 */
1275 if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
1276 xfs_trans_set_sync(tp);
1277
1278 /*
1279 * Attach the dquot(s) to the inodes and modify them incore.
1280 * These ids of the inode couldn't have changed since the new
1281 * inode has been locked ever since it was created.
1282 */
1283 xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp, pdqp);
1284
1285 error = xfs_defer_finish(&tp, &dfops, NULL);
1286 if (error)
1287 goto out_bmap_cancel;
1288
1289 error = xfs_trans_commit(tp);
1290 if (error)
1291 goto out_release_inode;
1292
1293 xfs_qm_dqrele(udqp);
1294 xfs_qm_dqrele(gdqp);
1295 xfs_qm_dqrele(pdqp);
1296
1297 *ipp = ip;
1298 return 0;
1299
1300 out_bmap_cancel:
1301 xfs_defer_cancel(&dfops);
1302 out_trans_cancel:
1303 xfs_trans_cancel(tp);
1304 out_release_inode:
1305 /*
1306 * Wait until after the current transaction is aborted to finish the
1307 * setup of the inode and release the inode. This prevents recursive
1308 * transactions and deadlocks from xfs_inactive.
1309 */
1310 if (ip) {
1311 xfs_finish_inode_setup(ip);
1312 IRELE(ip);
1313 }
1314
1315 xfs_qm_dqrele(udqp);
1316 xfs_qm_dqrele(gdqp);
1317 xfs_qm_dqrele(pdqp);
1318
1319 if (unlock_dp_on_error)
1320 xfs_iunlock(dp, XFS_ILOCK_EXCL);
1321 return error;
1322}
1323
1324int
1325xfs_create_tmpfile(
1326 struct xfs_inode *dp,
1327 struct dentry *dentry,
1328 umode_t mode,
1329 struct xfs_inode **ipp)
1330{
1331 struct xfs_mount *mp = dp->i_mount;
1332 struct xfs_inode *ip = NULL;
1333 struct xfs_trans *tp = NULL;
1334 int error;
1335 prid_t prid;
1336 struct xfs_dquot *udqp = NULL;
1337 struct xfs_dquot *gdqp = NULL;
1338 struct xfs_dquot *pdqp = NULL;
1339 struct xfs_trans_res *tres;
1340 uint resblks;
1341
1342 if (XFS_FORCED_SHUTDOWN(mp))
1343 return -EIO;
1344
1345 prid = xfs_get_initial_prid(dp);
1346
1347 /*
1348 * Make sure that we have allocated dquot(s) on disk.
1349 */
1350 error = xfs_qm_vop_dqalloc(dp, xfs_kuid_to_uid(current_fsuid()),
1351 xfs_kgid_to_gid(current_fsgid()), prid,
1352 XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
1353 &udqp, &gdqp, &pdqp);
1354 if (error)
1355 return error;
1356
1357 resblks = XFS_IALLOC_SPACE_RES(mp);
1358 tres = &M_RES(mp)->tr_create_tmpfile;
1359
1360 error = xfs_trans_alloc(mp, tres, resblks, 0, 0, &tp);
1361 if (error == -ENOSPC) {
1362 /* No space at all so try a "no-allocation" reservation */
1363 resblks = 0;
1364 error = xfs_trans_alloc(mp, tres, 0, 0, 0, &tp);
1365 }
1366 if (error)
1367 goto out_release_inode;
1368
1369 error = xfs_trans_reserve_quota(tp, mp, udqp, gdqp,
1370 pdqp, resblks, 1, 0);
1371 if (error)
1372 goto out_trans_cancel;
1373
1374 error = xfs_dir_ialloc(&tp, dp, mode, 1, 0,
1375 prid, resblks > 0, &ip, NULL);
1376 if (error)
1377 goto out_trans_cancel;
1378
1379 if (mp->m_flags & XFS_MOUNT_WSYNC)
1380 xfs_trans_set_sync(tp);
1381
1382 /*
1383 * Attach the dquot(s) to the inodes and modify them incore.
1384 * These ids of the inode couldn't have changed since the new
1385 * inode has been locked ever since it was created.
1386 */
1387 xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp, pdqp);
1388
1389 error = xfs_iunlink(tp, ip);
1390 if (error)
1391 goto out_trans_cancel;
1392
1393 error = xfs_trans_commit(tp);
1394 if (error)
1395 goto out_release_inode;
1396
1397 xfs_qm_dqrele(udqp);
1398 xfs_qm_dqrele(gdqp);
1399 xfs_qm_dqrele(pdqp);
1400
1401 *ipp = ip;
1402 return 0;
1403
1404 out_trans_cancel:
1405 xfs_trans_cancel(tp);
1406 out_release_inode:
1407 /*
1408 * Wait until after the current transaction is aborted to finish the
1409 * setup of the inode and release the inode. This prevents recursive
1410 * transactions and deadlocks from xfs_inactive.
1411 */
1412 if (ip) {
1413 xfs_finish_inode_setup(ip);
1414 IRELE(ip);
1415 }
1416
1417 xfs_qm_dqrele(udqp);
1418 xfs_qm_dqrele(gdqp);
1419 xfs_qm_dqrele(pdqp);
1420
1421 return error;
1422}
1423
1424int
1425xfs_link(
1426 xfs_inode_t *tdp,
1427 xfs_inode_t *sip,
1428 struct xfs_name *target_name)
1429{
1430 xfs_mount_t *mp = tdp->i_mount;
1431 xfs_trans_t *tp;
1432 int error;
1433 struct xfs_defer_ops dfops;
1434 xfs_fsblock_t first_block;
1435 int resblks;
1436
1437 trace_xfs_link(tdp, target_name);
1438
1439 ASSERT(!S_ISDIR(VFS_I(sip)->i_mode));
1440
1441 if (XFS_FORCED_SHUTDOWN(mp))
1442 return -EIO;
1443
1444 error = xfs_qm_dqattach(sip, 0);
1445 if (error)
1446 goto std_return;
1447
1448 error = xfs_qm_dqattach(tdp, 0);
1449 if (error)
1450 goto std_return;
1451
1452 resblks = XFS_LINK_SPACE_RES(mp, target_name->len);
1453 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_link, resblks, 0, 0, &tp);
1454 if (error == -ENOSPC) {
1455 resblks = 0;
1456 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_link, 0, 0, 0, &tp);
1457 }
1458 if (error)
1459 goto std_return;
1460
1461 xfs_lock_two_inodes(sip, tdp, XFS_ILOCK_EXCL);
1462
1463 xfs_trans_ijoin(tp, sip, XFS_ILOCK_EXCL);
1464 xfs_trans_ijoin(tp, tdp, XFS_ILOCK_EXCL);
1465
1466 /*
1467 * If we are using project inheritance, we only allow hard link
1468 * creation in our tree when the project IDs are the same; else
1469 * the tree quota mechanism could be circumvented.
1470 */
1471 if (unlikely((tdp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) &&
1472 (xfs_get_projid(tdp) != xfs_get_projid(sip)))) {
1473 error = -EXDEV;
1474 goto error_return;
1475 }
1476
1477 if (!resblks) {
1478 error = xfs_dir_canenter(tp, tdp, target_name);
1479 if (error)
1480 goto error_return;
1481 }
1482
1483 xfs_defer_init(&dfops, &first_block);
1484
1485 /*
1486 * Handle initial link state of O_TMPFILE inode
1487 */
1488 if (VFS_I(sip)->i_nlink == 0) {
1489 error = xfs_iunlink_remove(tp, sip);
1490 if (error)
1491 goto error_return;
1492 }
1493
1494 error = xfs_dir_createname(tp, tdp, target_name, sip->i_ino,
1495 &first_block, &dfops, resblks);
1496 if (error)
1497 goto error_return;
1498 xfs_trans_ichgtime(tp, tdp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1499 xfs_trans_log_inode(tp, tdp, XFS_ILOG_CORE);
1500
1501 error = xfs_bumplink(tp, sip);
1502 if (error)
1503 goto error_return;
1504
1505 /*
1506 * If this is a synchronous mount, make sure that the
1507 * link transaction goes to disk before returning to
1508 * the user.
1509 */
1510 if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
1511 xfs_trans_set_sync(tp);
1512
1513 error = xfs_defer_finish(&tp, &dfops, NULL);
1514 if (error) {
1515 xfs_defer_cancel(&dfops);
1516 goto error_return;
1517 }
1518
1519 return xfs_trans_commit(tp);
1520
1521 error_return:
1522 xfs_trans_cancel(tp);
1523 std_return:
1524 return error;
1525}
1526
1527/*
1528 * Free up the underlying blocks past new_size. The new size must be smaller
1529 * than the current size. This routine can be used both for the attribute and
1530 * data fork, and does not modify the inode size, which is left to the caller.
1531 *
1532 * The transaction passed to this routine must have made a permanent log
1533 * reservation of at least XFS_ITRUNCATE_LOG_RES. This routine may commit the
1534 * given transaction and start new ones, so make sure everything involved in
1535 * the transaction is tidy before calling here. Some transaction will be
1536 * returned to the caller to be committed. The incoming transaction must
1537 * already include the inode, and both inode locks must be held exclusively.
1538 * The inode must also be "held" within the transaction. On return the inode
1539 * will be "held" within the returned transaction. This routine does NOT
1540 * require any disk space to be reserved for it within the transaction.
1541 *
1542 * If we get an error, we must return with the inode locked and linked into the
1543 * current transaction. This keeps things simple for the higher level code,
1544 * because it always knows that the inode is locked and held in the transaction
1545 * that returns to it whether errors occur or not. We don't mark the inode
1546 * dirty on error so that transactions can be easily aborted if possible.
1547 */
1548int
1549xfs_itruncate_extents(
1550 struct xfs_trans **tpp,
1551 struct xfs_inode *ip,
1552 int whichfork,
1553 xfs_fsize_t new_size)
1554{
1555 struct xfs_mount *mp = ip->i_mount;
1556 struct xfs_trans *tp = *tpp;
1557 struct xfs_defer_ops dfops;
1558 xfs_fsblock_t first_block;
1559 xfs_fileoff_t first_unmap_block;
1560 xfs_fileoff_t last_block;
1561 xfs_filblks_t unmap_len;
1562 int error = 0;
1563 int done = 0;
1564
1565 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
1566 ASSERT(!atomic_read(&VFS_I(ip)->i_count) ||
1567 xfs_isilocked(ip, XFS_IOLOCK_EXCL));
1568 ASSERT(new_size <= XFS_ISIZE(ip));
1569 ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
1570 ASSERT(ip->i_itemp != NULL);
1571 ASSERT(ip->i_itemp->ili_lock_flags == 0);
1572 ASSERT(!XFS_NOT_DQATTACHED(mp, ip));
1573
1574 trace_xfs_itruncate_extents_start(ip, new_size);
1575
1576 /*
1577 * Since it is possible for space to become allocated beyond
1578 * the end of the file (in a crash where the space is allocated
1579 * but the inode size is not yet updated), simply remove any
1580 * blocks which show up between the new EOF and the maximum
1581 * possible file size. If the first block to be removed is
1582 * beyond the maximum file size (ie it is the same as last_block),
1583 * then there is nothing to do.
1584 */
1585 first_unmap_block = XFS_B_TO_FSB(mp, (xfs_ufsize_t)new_size);
1586 last_block = XFS_B_TO_FSB(mp, mp->m_super->s_maxbytes);
1587 if (first_unmap_block == last_block)
1588 return 0;
1589
1590 ASSERT(first_unmap_block < last_block);
1591 unmap_len = last_block - first_unmap_block + 1;
1592 while (!done) {
1593 xfs_defer_init(&dfops, &first_block);
1594 error = xfs_bunmapi(tp, ip,
1595 first_unmap_block, unmap_len,
1596 xfs_bmapi_aflag(whichfork),
1597 XFS_ITRUNC_MAX_EXTENTS,
1598 &first_block, &dfops,
1599 &done);
1600 if (error)
1601 goto out_bmap_cancel;
1602
1603 /*
1604 * Duplicate the transaction that has the permanent
1605 * reservation and commit the old transaction.
1606 */
1607 error = xfs_defer_finish(&tp, &dfops, ip);
1608 if (error)
1609 goto out_bmap_cancel;
1610
1611 error = xfs_trans_roll(&tp, ip);
1612 if (error)
1613 goto out;
1614 }
1615
1616 /* Remove all pending CoW reservations. */
1617 error = xfs_reflink_cancel_cow_blocks(ip, &tp, first_unmap_block,
1618 last_block, true);
1619 if (error)
1620 goto out;
1621
1622 /*
1623 * Clear the reflink flag if we truncated everything.
1624 */
1625 if (ip->i_d.di_nblocks == 0 && xfs_is_reflink_inode(ip)) {
1626 ip->i_d.di_flags2 &= ~XFS_DIFLAG2_REFLINK;
1627 xfs_inode_clear_cowblocks_tag(ip);
1628 }
1629
1630 /*
1631 * Always re-log the inode so that our permanent transaction can keep
1632 * on rolling it forward in the log.
1633 */
1634 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1635
1636 trace_xfs_itruncate_extents_end(ip, new_size);
1637
1638out:
1639 *tpp = tp;
1640 return error;
1641out_bmap_cancel:
1642 /*
1643 * If the bunmapi call encounters an error, return to the caller where
1644 * the transaction can be properly aborted. We just need to make sure
1645 * we're not holding any resources that we were not when we came in.
1646 */
1647 xfs_defer_cancel(&dfops);
1648 goto out;
1649}
1650
1651int
1652xfs_release(
1653 xfs_inode_t *ip)
1654{
1655 xfs_mount_t *mp = ip->i_mount;
1656 int error;
1657
1658 if (!S_ISREG(VFS_I(ip)->i_mode) || (VFS_I(ip)->i_mode == 0))
1659 return 0;
1660
1661 /* If this is a read-only mount, don't do this (would generate I/O) */
1662 if (mp->m_flags & XFS_MOUNT_RDONLY)
1663 return 0;
1664
1665 if (!XFS_FORCED_SHUTDOWN(mp)) {
1666 int truncated;
1667
1668 /*
1669 * If we previously truncated this file and removed old data
1670 * in the process, we want to initiate "early" writeout on
1671 * the last close. This is an attempt to combat the notorious
1672 * NULL files problem which is particularly noticeable from a
1673 * truncate down, buffered (re-)write (delalloc), followed by
1674 * a crash. What we are effectively doing here is
1675 * significantly reducing the time window where we'd otherwise
1676 * be exposed to that problem.
1677 */
1678 truncated = xfs_iflags_test_and_clear(ip, XFS_ITRUNCATED);
1679 if (truncated) {
1680 xfs_iflags_clear(ip, XFS_IDIRTY_RELEASE);
1681 if (ip->i_delayed_blks > 0) {
1682 error = filemap_flush(VFS_I(ip)->i_mapping);
1683 if (error)
1684 return error;
1685 }
1686 }
1687 }
1688
1689 if (VFS_I(ip)->i_nlink == 0)
1690 return 0;
1691
1692 if (xfs_can_free_eofblocks(ip, false)) {
1693
1694 /*
1695 * Check if the inode is being opened, written and closed
1696 * frequently and we have delayed allocation blocks outstanding
1697 * (e.g. streaming writes from the NFS server), truncating the
1698 * blocks past EOF will cause fragmentation to occur.
1699 *
1700 * In this case don't do the truncation, but we have to be
1701 * careful how we detect this case. Blocks beyond EOF show up as
1702 * i_delayed_blks even when the inode is clean, so we need to
1703 * truncate them away first before checking for a dirty release.
1704 * Hence on the first dirty close we will still remove the
1705 * speculative allocation, but after that we will leave it in
1706 * place.
1707 */
1708 if (xfs_iflags_test(ip, XFS_IDIRTY_RELEASE))
1709 return 0;
1710 /*
1711 * If we can't get the iolock just skip truncating the blocks
1712 * past EOF because we could deadlock with the mmap_sem
1713 * otherwise. We'll get another chance to drop them once the
1714 * last reference to the inode is dropped, so we'll never leak
1715 * blocks permanently.
1716 */
1717 if (xfs_ilock_nowait(ip, XFS_IOLOCK_EXCL)) {
1718 error = xfs_free_eofblocks(ip);
1719 xfs_iunlock(ip, XFS_IOLOCK_EXCL);
1720 if (error)
1721 return error;
1722 }
1723
1724 /* delalloc blocks after truncation means it really is dirty */
1725 if (ip->i_delayed_blks)
1726 xfs_iflags_set(ip, XFS_IDIRTY_RELEASE);
1727 }
1728 return 0;
1729}
1730
1731/*
1732 * xfs_inactive_truncate
1733 *
1734 * Called to perform a truncate when an inode becomes unlinked.
1735 */
1736STATIC int
1737xfs_inactive_truncate(
1738 struct xfs_inode *ip)
1739{
1740 struct xfs_mount *mp = ip->i_mount;
1741 struct xfs_trans *tp;
1742 int error;
1743
1744 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, 0, 0, 0, &tp);
1745 if (error) {
1746 ASSERT(XFS_FORCED_SHUTDOWN(mp));
1747 return error;
1748 }
1749
1750 xfs_ilock(ip, XFS_ILOCK_EXCL);
1751 xfs_trans_ijoin(tp, ip, 0);
1752
1753 /*
1754 * Log the inode size first to prevent stale data exposure in the event
1755 * of a system crash before the truncate completes. See the related
1756 * comment in xfs_vn_setattr_size() for details.
1757 */
1758 ip->i_d.di_size = 0;
1759 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1760
1761 error = xfs_itruncate_extents(&tp, ip, XFS_DATA_FORK, 0);
1762 if (error)
1763 goto error_trans_cancel;
1764
1765 ASSERT(ip->i_d.di_nextents == 0);
1766
1767 error = xfs_trans_commit(tp);
1768 if (error)
1769 goto error_unlock;
1770
1771 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1772 return 0;
1773
1774error_trans_cancel:
1775 xfs_trans_cancel(tp);
1776error_unlock:
1777 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1778 return error;
1779}
1780
1781/*
1782 * xfs_inactive_ifree()
1783 *
1784 * Perform the inode free when an inode is unlinked.
1785 */
1786STATIC int
1787xfs_inactive_ifree(
1788 struct xfs_inode *ip)
1789{
1790 struct xfs_defer_ops dfops;
1791 xfs_fsblock_t first_block;
1792 struct xfs_mount *mp = ip->i_mount;
1793 struct xfs_trans *tp;
1794 int error;
1795
1796 /*
1797 * We try to use a per-AG reservation for any block needed by the finobt
1798 * tree, but as the finobt feature predates the per-AG reservation
1799 * support a degraded file system might not have enough space for the
1800 * reservation at mount time. In that case try to dip into the reserved
1801 * pool and pray.
1802 *
1803 * Send a warning if the reservation does happen to fail, as the inode
1804 * now remains allocated and sits on the unlinked list until the fs is
1805 * repaired.
1806 */
1807 if (unlikely(mp->m_inotbt_nores)) {
1808 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ifree,
1809 XFS_IFREE_SPACE_RES(mp), 0, XFS_TRANS_RESERVE,
1810 &tp);
1811 } else {
1812 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ifree, 0, 0, 0, &tp);
1813 }
1814 if (error) {
1815 if (error == -ENOSPC) {
1816 xfs_warn_ratelimited(mp,
1817 "Failed to remove inode(s) from unlinked list. "
1818 "Please free space, unmount and run xfs_repair.");
1819 } else {
1820 ASSERT(XFS_FORCED_SHUTDOWN(mp));
1821 }
1822 return error;
1823 }
1824
1825 xfs_ilock(ip, XFS_ILOCK_EXCL);
1826 xfs_trans_ijoin(tp, ip, 0);
1827
1828 xfs_defer_init(&dfops, &first_block);
1829 error = xfs_ifree(tp, ip, &dfops);
1830 if (error) {
1831 /*
1832 * If we fail to free the inode, shut down. The cancel
1833 * might do that, we need to make sure. Otherwise the
1834 * inode might be lost for a long time or forever.
1835 */
1836 if (!XFS_FORCED_SHUTDOWN(mp)) {
1837 xfs_notice(mp, "%s: xfs_ifree returned error %d",
1838 __func__, error);
1839 xfs_force_shutdown(mp, SHUTDOWN_META_IO_ERROR);
1840 }
1841 xfs_trans_cancel(tp);
1842 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1843 return error;
1844 }
1845
1846 /*
1847 * Credit the quota account(s). The inode is gone.
1848 */
1849 xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_ICOUNT, -1);
1850
1851 /*
1852 * Just ignore errors at this point. There is nothing we can do except
1853 * to try to keep going. Make sure it's not a silent error.
1854 */
1855 error = xfs_defer_finish(&tp, &dfops, NULL);
1856 if (error) {
1857 xfs_notice(mp, "%s: xfs_defer_finish returned error %d",
1858 __func__, error);
1859 xfs_defer_cancel(&dfops);
1860 }
1861 error = xfs_trans_commit(tp);
1862 if (error)
1863 xfs_notice(mp, "%s: xfs_trans_commit returned error %d",
1864 __func__, error);
1865
1866 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1867 return 0;
1868}
1869
1870/*
1871 * xfs_inactive
1872 *
1873 * This is called when the vnode reference count for the vnode
1874 * goes to zero. If the file has been unlinked, then it must
1875 * now be truncated. Also, we clear all of the read-ahead state
1876 * kept for the inode here since the file is now closed.
1877 */
1878void
1879xfs_inactive(
1880 xfs_inode_t *ip)
1881{
1882 struct xfs_mount *mp;
1883 int error;
1884 int truncate = 0;
1885
1886 /*
1887 * If the inode is already free, then there can be nothing
1888 * to clean up here.
1889 */
1890 if (VFS_I(ip)->i_mode == 0) {
1891 ASSERT(ip->i_df.if_real_bytes == 0);
1892 ASSERT(ip->i_df.if_broot_bytes == 0);
1893 return;
1894 }
1895
1896 mp = ip->i_mount;
1897 ASSERT(!xfs_iflags_test(ip, XFS_IRECOVERY));
1898
1899 /* If this is a read-only mount, don't do this (would generate I/O) */
1900 if (mp->m_flags & XFS_MOUNT_RDONLY)
1901 return;
1902
1903 if (VFS_I(ip)->i_nlink != 0) {
1904 /*
1905 * force is true because we are evicting an inode from the
1906 * cache. Post-eof blocks must be freed, lest we end up with
1907 * broken free space accounting.
1908 */
1909 if (xfs_can_free_eofblocks(ip, true)) {
1910 xfs_ilock(ip, XFS_IOLOCK_EXCL);
1911 xfs_free_eofblocks(ip);
1912 xfs_iunlock(ip, XFS_IOLOCK_EXCL);
1913 }
1914
1915 return;
1916 }
1917
1918 if (S_ISREG(VFS_I(ip)->i_mode) &&
1919 (ip->i_d.di_size != 0 || XFS_ISIZE(ip) != 0 ||
1920 ip->i_d.di_nextents > 0 || ip->i_delayed_blks > 0))
1921 truncate = 1;
1922
1923 error = xfs_qm_dqattach(ip, 0);
1924 if (error)
1925 return;
1926
1927 if (S_ISLNK(VFS_I(ip)->i_mode))
1928 error = xfs_inactive_symlink(ip);
1929 else if (truncate)
1930 error = xfs_inactive_truncate(ip);
1931 if (error)
1932 return;
1933
1934 /*
1935 * If there are attributes associated with the file then blow them away
1936 * now. The code calls a routine that recursively deconstructs the
1937 * attribute fork. If also blows away the in-core attribute fork.
1938 */
1939 if (XFS_IFORK_Q(ip)) {
1940 error = xfs_attr_inactive(ip);
1941 if (error)
1942 return;
1943 }
1944
1945 ASSERT(!ip->i_afp);
1946 ASSERT(ip->i_d.di_anextents == 0);
1947 ASSERT(ip->i_d.di_forkoff == 0);
1948
1949 /*
1950 * Free the inode.
1951 */
1952 error = xfs_inactive_ifree(ip);
1953 if (error)
1954 return;
1955
1956 /*
1957 * Release the dquots held by inode, if any.
1958 */
1959 xfs_qm_dqdetach(ip);
1960}
1961
1962/*
1963 * This is called when the inode's link count goes to 0 or we are creating a
1964 * tmpfile via O_TMPFILE. In the case of a tmpfile, @ignore_linkcount will be
1965 * set to true as the link count is dropped to zero by the VFS after we've
1966 * created the file successfully, so we have to add it to the unlinked list
1967 * while the link count is non-zero.
1968 *
1969 * We place the on-disk inode on a list in the AGI. It will be pulled from this
1970 * list when the inode is freed.
1971 */
1972STATIC int
1973xfs_iunlink(
1974 struct xfs_trans *tp,
1975 struct xfs_inode *ip)
1976{
1977 xfs_mount_t *mp = tp->t_mountp;
1978 xfs_agi_t *agi;
1979 xfs_dinode_t *dip;
1980 xfs_buf_t *agibp;
1981 xfs_buf_t *ibp;
1982 xfs_agino_t agino;
1983 short bucket_index;
1984 int offset;
1985 int error;
1986
1987 ASSERT(VFS_I(ip)->i_mode != 0);
1988
1989 /*
1990 * Get the agi buffer first. It ensures lock ordering
1991 * on the list.
1992 */
1993 error = xfs_read_agi(mp, tp, XFS_INO_TO_AGNO(mp, ip->i_ino), &agibp);
1994 if (error)
1995 return error;
1996 agi = XFS_BUF_TO_AGI(agibp);
1997
1998 /*
1999 * Get the index into the agi hash table for the
2000 * list this inode will go on.
2001 */
2002 agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
2003 ASSERT(agino != 0);
2004 bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
2005 ASSERT(agi->agi_unlinked[bucket_index]);
2006 ASSERT(be32_to_cpu(agi->agi_unlinked[bucket_index]) != agino);
2007
2008 if (agi->agi_unlinked[bucket_index] != cpu_to_be32(NULLAGINO)) {
2009 /*
2010 * There is already another inode in the bucket we need
2011 * to add ourselves to. Add us at the front of the list.
2012 * Here we put the head pointer into our next pointer,
2013 * and then we fall through to point the head at us.
2014 */
2015 error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &ibp,
2016 0, 0);
2017 if (error)
2018 return error;
2019
2020 ASSERT(dip->di_next_unlinked == cpu_to_be32(NULLAGINO));
2021 dip->di_next_unlinked = agi->agi_unlinked[bucket_index];
2022 offset = ip->i_imap.im_boffset +
2023 offsetof(xfs_dinode_t, di_next_unlinked);
2024
2025 /* need to recalc the inode CRC if appropriate */
2026 xfs_dinode_calc_crc(mp, dip);
2027
2028 xfs_trans_inode_buf(tp, ibp);
2029 xfs_trans_log_buf(tp, ibp, offset,
2030 (offset + sizeof(xfs_agino_t) - 1));
2031 xfs_inobp_check(mp, ibp);
2032 }
2033
2034 /*
2035 * Point the bucket head pointer at the inode being inserted.
2036 */
2037 ASSERT(agino != 0);
2038 agi->agi_unlinked[bucket_index] = cpu_to_be32(agino);
2039 offset = offsetof(xfs_agi_t, agi_unlinked) +
2040 (sizeof(xfs_agino_t) * bucket_index);
2041 xfs_trans_log_buf(tp, agibp, offset,
2042 (offset + sizeof(xfs_agino_t) - 1));
2043 return 0;
2044}
2045
2046/*
2047 * Pull the on-disk inode from the AGI unlinked list.
2048 */
2049STATIC int
2050xfs_iunlink_remove(
2051 xfs_trans_t *tp,
2052 xfs_inode_t *ip)
2053{
2054 xfs_ino_t next_ino;
2055 xfs_mount_t *mp;
2056 xfs_agi_t *agi;
2057 xfs_dinode_t *dip;
2058 xfs_buf_t *agibp;
2059 xfs_buf_t *ibp;
2060 xfs_agnumber_t agno;
2061 xfs_agino_t agino;
2062 xfs_agino_t next_agino;
2063 xfs_buf_t *last_ibp;
2064 xfs_dinode_t *last_dip = NULL;
2065 short bucket_index;
2066 int offset, last_offset = 0;
2067 int error;
2068
2069 mp = tp->t_mountp;
2070 agno = XFS_INO_TO_AGNO(mp, ip->i_ino);
2071
2072 /*
2073 * Get the agi buffer first. It ensures lock ordering
2074 * on the list.
2075 */
2076 error = xfs_read_agi(mp, tp, agno, &agibp);
2077 if (error)
2078 return error;
2079
2080 agi = XFS_BUF_TO_AGI(agibp);
2081
2082 /*
2083 * Get the index into the agi hash table for the
2084 * list this inode will go on.
2085 */
2086 agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
2087 ASSERT(agino != 0);
2088 bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
2089 ASSERT(agi->agi_unlinked[bucket_index] != cpu_to_be32(NULLAGINO));
2090 ASSERT(agi->agi_unlinked[bucket_index]);
2091
2092 if (be32_to_cpu(agi->agi_unlinked[bucket_index]) == agino) {
2093 /*
2094 * We're at the head of the list. Get the inode's on-disk
2095 * buffer to see if there is anyone after us on the list.
2096 * Only modify our next pointer if it is not already NULLAGINO.
2097 * This saves us the overhead of dealing with the buffer when
2098 * there is no need to change it.
2099 */
2100 error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &ibp,
2101 0, 0);
2102 if (error) {
2103 xfs_warn(mp, "%s: xfs_imap_to_bp returned error %d.",
2104 __func__, error);
2105 return error;
2106 }
2107 next_agino = be32_to_cpu(dip->di_next_unlinked);
2108 ASSERT(next_agino != 0);
2109 if (next_agino != NULLAGINO) {
2110 dip->di_next_unlinked = cpu_to_be32(NULLAGINO);
2111 offset = ip->i_imap.im_boffset +
2112 offsetof(xfs_dinode_t, di_next_unlinked);
2113
2114 /* need to recalc the inode CRC if appropriate */
2115 xfs_dinode_calc_crc(mp, dip);
2116
2117 xfs_trans_inode_buf(tp, ibp);
2118 xfs_trans_log_buf(tp, ibp, offset,
2119 (offset + sizeof(xfs_agino_t) - 1));
2120 xfs_inobp_check(mp, ibp);
2121 } else {
2122 xfs_trans_brelse(tp, ibp);
2123 }
2124 /*
2125 * Point the bucket head pointer at the next inode.
2126 */
2127 ASSERT(next_agino != 0);
2128 ASSERT(next_agino != agino);
2129 agi->agi_unlinked[bucket_index] = cpu_to_be32(next_agino);
2130 offset = offsetof(xfs_agi_t, agi_unlinked) +
2131 (sizeof(xfs_agino_t) * bucket_index);
2132 xfs_trans_log_buf(tp, agibp, offset,
2133 (offset + sizeof(xfs_agino_t) - 1));
2134 } else {
2135 /*
2136 * We need to search the list for the inode being freed.
2137 */
2138 next_agino = be32_to_cpu(agi->agi_unlinked[bucket_index]);
2139 last_ibp = NULL;
2140 while (next_agino != agino) {
2141 struct xfs_imap imap;
2142
2143 if (last_ibp)
2144 xfs_trans_brelse(tp, last_ibp);
2145
2146 imap.im_blkno = 0;
2147 next_ino = XFS_AGINO_TO_INO(mp, agno, next_agino);
2148
2149 error = xfs_imap(mp, tp, next_ino, &imap, 0);
2150 if (error) {
2151 xfs_warn(mp,
2152 "%s: xfs_imap returned error %d.",
2153 __func__, error);
2154 return error;
2155 }
2156
2157 error = xfs_imap_to_bp(mp, tp, &imap, &last_dip,
2158 &last_ibp, 0, 0);
2159 if (error) {
2160 xfs_warn(mp,
2161 "%s: xfs_imap_to_bp returned error %d.",
2162 __func__, error);
2163 return error;
2164 }
2165
2166 last_offset = imap.im_boffset;
2167 next_agino = be32_to_cpu(last_dip->di_next_unlinked);
2168 ASSERT(next_agino != NULLAGINO);
2169 ASSERT(next_agino != 0);
2170 }
2171
2172 /*
2173 * Now last_ibp points to the buffer previous to us on the
2174 * unlinked list. Pull us from the list.
2175 */
2176 error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &ibp,
2177 0, 0);
2178 if (error) {
2179 xfs_warn(mp, "%s: xfs_imap_to_bp(2) returned error %d.",
2180 __func__, error);
2181 return error;
2182 }
2183 next_agino = be32_to_cpu(dip->di_next_unlinked);
2184 ASSERT(next_agino != 0);
2185 ASSERT(next_agino != agino);
2186 if (next_agino != NULLAGINO) {
2187 dip->di_next_unlinked = cpu_to_be32(NULLAGINO);
2188 offset = ip->i_imap.im_boffset +
2189 offsetof(xfs_dinode_t, di_next_unlinked);
2190
2191 /* need to recalc the inode CRC if appropriate */
2192 xfs_dinode_calc_crc(mp, dip);
2193
2194 xfs_trans_inode_buf(tp, ibp);
2195 xfs_trans_log_buf(tp, ibp, offset,
2196 (offset + sizeof(xfs_agino_t) - 1));
2197 xfs_inobp_check(mp, ibp);
2198 } else {
2199 xfs_trans_brelse(tp, ibp);
2200 }
2201 /*
2202 * Point the previous inode on the list to the next inode.
2203 */
2204 last_dip->di_next_unlinked = cpu_to_be32(next_agino);
2205 ASSERT(next_agino != 0);
2206 offset = last_offset + offsetof(xfs_dinode_t, di_next_unlinked);
2207
2208 /* need to recalc the inode CRC if appropriate */
2209 xfs_dinode_calc_crc(mp, last_dip);
2210
2211 xfs_trans_inode_buf(tp, last_ibp);
2212 xfs_trans_log_buf(tp, last_ibp, offset,
2213 (offset + sizeof(xfs_agino_t) - 1));
2214 xfs_inobp_check(mp, last_ibp);
2215 }
2216 return 0;
2217}
2218
2219/*
2220 * A big issue when freeing the inode cluster is that we _cannot_ skip any
2221 * inodes that are in memory - they all must be marked stale and attached to
2222 * the cluster buffer.
2223 */
2224STATIC int
2225xfs_ifree_cluster(
2226 xfs_inode_t *free_ip,
2227 xfs_trans_t *tp,
2228 struct xfs_icluster *xic)
2229{
2230 xfs_mount_t *mp = free_ip->i_mount;
2231 int blks_per_cluster;
2232 int inodes_per_cluster;
2233 int nbufs;
2234 int i, j;
2235 int ioffset;
2236 xfs_daddr_t blkno;
2237 xfs_buf_t *bp;
2238 xfs_inode_t *ip;
2239 xfs_inode_log_item_t *iip;
2240 xfs_log_item_t *lip;
2241 struct xfs_perag *pag;
2242 xfs_ino_t inum;
2243
2244 inum = xic->first_ino;
2245 pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, inum));
2246 blks_per_cluster = xfs_icluster_size_fsb(mp);
2247 inodes_per_cluster = blks_per_cluster << mp->m_sb.sb_inopblog;
2248 nbufs = mp->m_ialloc_blks / blks_per_cluster;
2249
2250 for (j = 0; j < nbufs; j++, inum += inodes_per_cluster) {
2251 /*
2252 * The allocation bitmap tells us which inodes of the chunk were
2253 * physically allocated. Skip the cluster if an inode falls into
2254 * a sparse region.
2255 */
2256 ioffset = inum - xic->first_ino;
2257 if ((xic->alloc & XFS_INOBT_MASK(ioffset)) == 0) {
2258 ASSERT(do_mod(ioffset, inodes_per_cluster) == 0);
2259 continue;
2260 }
2261
2262 blkno = XFS_AGB_TO_DADDR(mp, XFS_INO_TO_AGNO(mp, inum),
2263 XFS_INO_TO_AGBNO(mp, inum));
2264
2265 /*
2266 * We obtain and lock the backing buffer first in the process
2267 * here, as we have to ensure that any dirty inode that we
2268 * can't get the flush lock on is attached to the buffer.
2269 * If we scan the in-memory inodes first, then buffer IO can
2270 * complete before we get a lock on it, and hence we may fail
2271 * to mark all the active inodes on the buffer stale.
2272 */
2273 bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, blkno,
2274 mp->m_bsize * blks_per_cluster,
2275 XBF_UNMAPPED);
2276
2277 if (!bp)
2278 return -ENOMEM;
2279
2280 /*
2281 * This buffer may not have been correctly initialised as we
2282 * didn't read it from disk. That's not important because we are
2283 * only using to mark the buffer as stale in the log, and to
2284 * attach stale cached inodes on it. That means it will never be
2285 * dispatched for IO. If it is, we want to know about it, and we
2286 * want it to fail. We can acheive this by adding a write
2287 * verifier to the buffer.
2288 */
2289 bp->b_ops = &xfs_inode_buf_ops;
2290
2291 /*
2292 * Walk the inodes already attached to the buffer and mark them
2293 * stale. These will all have the flush locks held, so an
2294 * in-memory inode walk can't lock them. By marking them all
2295 * stale first, we will not attempt to lock them in the loop
2296 * below as the XFS_ISTALE flag will be set.
2297 */
2298 lip = bp->b_fspriv;
2299 while (lip) {
2300 if (lip->li_type == XFS_LI_INODE) {
2301 iip = (xfs_inode_log_item_t *)lip;
2302 ASSERT(iip->ili_logged == 1);
2303 lip->li_cb = xfs_istale_done;
2304 xfs_trans_ail_copy_lsn(mp->m_ail,
2305 &iip->ili_flush_lsn,
2306 &iip->ili_item.li_lsn);
2307 xfs_iflags_set(iip->ili_inode, XFS_ISTALE);
2308 }
2309 lip = lip->li_bio_list;
2310 }
2311
2312
2313 /*
2314 * For each inode in memory attempt to add it to the inode
2315 * buffer and set it up for being staled on buffer IO
2316 * completion. This is safe as we've locked out tail pushing
2317 * and flushing by locking the buffer.
2318 *
2319 * We have already marked every inode that was part of a
2320 * transaction stale above, which means there is no point in
2321 * even trying to lock them.
2322 */
2323 for (i = 0; i < inodes_per_cluster; i++) {
2324retry:
2325 rcu_read_lock();
2326 ip = radix_tree_lookup(&pag->pag_ici_root,
2327 XFS_INO_TO_AGINO(mp, (inum + i)));
2328
2329 /* Inode not in memory, nothing to do */
2330 if (!ip) {
2331 rcu_read_unlock();
2332 continue;
2333 }
2334
2335 /*
2336 * because this is an RCU protected lookup, we could
2337 * find a recently freed or even reallocated inode
2338 * during the lookup. We need to check under the
2339 * i_flags_lock for a valid inode here. Skip it if it
2340 * is not valid, the wrong inode or stale.
2341 */
2342 spin_lock(&ip->i_flags_lock);
2343 if (ip->i_ino != inum + i ||
2344 __xfs_iflags_test(ip, XFS_ISTALE)) {
2345 spin_unlock(&ip->i_flags_lock);
2346 rcu_read_unlock();
2347 continue;
2348 }
2349 spin_unlock(&ip->i_flags_lock);
2350
2351 /*
2352 * Don't try to lock/unlock the current inode, but we
2353 * _cannot_ skip the other inodes that we did not find
2354 * in the list attached to the buffer and are not
2355 * already marked stale. If we can't lock it, back off
2356 * and retry.
2357 */
2358 if (ip != free_ip &&
2359 !xfs_ilock_nowait(ip, XFS_ILOCK_EXCL)) {
2360 rcu_read_unlock();
2361 delay(1);
2362 goto retry;
2363 }
2364 rcu_read_unlock();
2365
2366 xfs_iflock(ip);
2367 xfs_iflags_set(ip, XFS_ISTALE);
2368
2369 /*
2370 * we don't need to attach clean inodes or those only
2371 * with unlogged changes (which we throw away, anyway).
2372 */
2373 iip = ip->i_itemp;
2374 if (!iip || xfs_inode_clean(ip)) {
2375 ASSERT(ip != free_ip);
2376 xfs_ifunlock(ip);
2377 xfs_iunlock(ip, XFS_ILOCK_EXCL);
2378 continue;
2379 }
2380
2381 iip->ili_last_fields = iip->ili_fields;
2382 iip->ili_fields = 0;
2383 iip->ili_fsync_fields = 0;
2384 iip->ili_logged = 1;
2385 xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn,
2386 &iip->ili_item.li_lsn);
2387
2388 xfs_buf_attach_iodone(bp, xfs_istale_done,
2389 &iip->ili_item);
2390
2391 if (ip != free_ip)
2392 xfs_iunlock(ip, XFS_ILOCK_EXCL);
2393 }
2394
2395 xfs_trans_stale_inode_buf(tp, bp);
2396 xfs_trans_binval(tp, bp);
2397 }
2398
2399 xfs_perag_put(pag);
2400 return 0;
2401}
2402
2403/*
2404 * This is called to return an inode to the inode free list.
2405 * The inode should already be truncated to 0 length and have
2406 * no pages associated with it. This routine also assumes that
2407 * the inode is already a part of the transaction.
2408 *
2409 * The on-disk copy of the inode will have been added to the list
2410 * of unlinked inodes in the AGI. We need to remove the inode from
2411 * that list atomically with respect to freeing it here.
2412 */
2413int
2414xfs_ifree(
2415 xfs_trans_t *tp,
2416 xfs_inode_t *ip,
2417 struct xfs_defer_ops *dfops)
2418{
2419 int error;
2420 struct xfs_icluster xic = { 0 };
2421
2422 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
2423 ASSERT(VFS_I(ip)->i_nlink == 0);
2424 ASSERT(ip->i_d.di_nextents == 0);
2425 ASSERT(ip->i_d.di_anextents == 0);
2426 ASSERT(ip->i_d.di_size == 0 || !S_ISREG(VFS_I(ip)->i_mode));
2427 ASSERT(ip->i_d.di_nblocks == 0);
2428
2429 /*
2430 * Pull the on-disk inode from the AGI unlinked list.
2431 */
2432 error = xfs_iunlink_remove(tp, ip);
2433 if (error)
2434 return error;
2435
2436 error = xfs_difree(tp, ip->i_ino, dfops, &xic);
2437 if (error)
2438 return error;
2439
2440 VFS_I(ip)->i_mode = 0; /* mark incore inode as free */
2441 ip->i_d.di_flags = 0;
2442 ip->i_d.di_dmevmask = 0;
2443 ip->i_d.di_forkoff = 0; /* mark the attr fork not in use */
2444 ip->i_d.di_format = XFS_DINODE_FMT_EXTENTS;
2445 ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;
2446 /*
2447 * Bump the generation count so no one will be confused
2448 * by reincarnations of this inode.
2449 */
2450 VFS_I(ip)->i_generation++;
2451 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
2452
2453 if (xic.deleted)
2454 error = xfs_ifree_cluster(ip, tp, &xic);
2455
2456 return error;
2457}
2458
2459/*
2460 * This is called to unpin an inode. The caller must have the inode locked
2461 * in at least shared mode so that the buffer cannot be subsequently pinned
2462 * once someone is waiting for it to be unpinned.
2463 */
2464static void
2465xfs_iunpin(
2466 struct xfs_inode *ip)
2467{
2468 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
2469
2470 trace_xfs_inode_unpin_nowait(ip, _RET_IP_);
2471
2472 /* Give the log a push to start the unpinning I/O */
2473 xfs_log_force_lsn(ip->i_mount, ip->i_itemp->ili_last_lsn, 0);
2474
2475}
2476
2477static void
2478__xfs_iunpin_wait(
2479 struct xfs_inode *ip)
2480{
2481 wait_queue_head_t *wq = bit_waitqueue(&ip->i_flags, __XFS_IPINNED_BIT);
2482 DEFINE_WAIT_BIT(wait, &ip->i_flags, __XFS_IPINNED_BIT);
2483
2484 xfs_iunpin(ip);
2485
2486 do {
2487 prepare_to_wait(wq, &wait.wait, TASK_UNINTERRUPTIBLE);
2488 if (xfs_ipincount(ip))
2489 io_schedule();
2490 } while (xfs_ipincount(ip));
2491 finish_wait(wq, &wait.wait);
2492}
2493
2494void
2495xfs_iunpin_wait(
2496 struct xfs_inode *ip)
2497{
2498 if (xfs_ipincount(ip))
2499 __xfs_iunpin_wait(ip);
2500}
2501
2502/*
2503 * Removing an inode from the namespace involves removing the directory entry
2504 * and dropping the link count on the inode. Removing the directory entry can
2505 * result in locking an AGF (directory blocks were freed) and removing a link
2506 * count can result in placing the inode on an unlinked list which results in
2507 * locking an AGI.
2508 *
2509 * The big problem here is that we have an ordering constraint on AGF and AGI
2510 * locking - inode allocation locks the AGI, then can allocate a new extent for
2511 * new inodes, locking the AGF after the AGI. Similarly, freeing the inode
2512 * removes the inode from the unlinked list, requiring that we lock the AGI
2513 * first, and then freeing the inode can result in an inode chunk being freed
2514 * and hence freeing disk space requiring that we lock an AGF.
2515 *
2516 * Hence the ordering that is imposed by other parts of the code is AGI before
2517 * AGF. This means we cannot remove the directory entry before we drop the inode
2518 * reference count and put it on the unlinked list as this results in a lock
2519 * order of AGF then AGI, and this can deadlock against inode allocation and
2520 * freeing. Therefore we must drop the link counts before we remove the
2521 * directory entry.
2522 *
2523 * This is still safe from a transactional point of view - it is not until we
2524 * get to xfs_defer_finish() that we have the possibility of multiple
2525 * transactions in this operation. Hence as long as we remove the directory
2526 * entry and drop the link count in the first transaction of the remove
2527 * operation, there are no transactional constraints on the ordering here.
2528 */
2529int
2530xfs_remove(
2531 xfs_inode_t *dp,
2532 struct xfs_name *name,
2533 xfs_inode_t *ip)
2534{
2535 xfs_mount_t *mp = dp->i_mount;
2536 xfs_trans_t *tp = NULL;
2537 int is_dir = S_ISDIR(VFS_I(ip)->i_mode);
2538 int error = 0;
2539 struct xfs_defer_ops dfops;
2540 xfs_fsblock_t first_block;
2541 uint resblks;
2542
2543 trace_xfs_remove(dp, name);
2544
2545 if (XFS_FORCED_SHUTDOWN(mp))
2546 return -EIO;
2547
2548 error = xfs_qm_dqattach(dp, 0);
2549 if (error)
2550 goto std_return;
2551
2552 error = xfs_qm_dqattach(ip, 0);
2553 if (error)
2554 goto std_return;
2555
2556 /*
2557 * We try to get the real space reservation first,
2558 * allowing for directory btree deletion(s) implying
2559 * possible bmap insert(s). If we can't get the space
2560 * reservation then we use 0 instead, and avoid the bmap
2561 * btree insert(s) in the directory code by, if the bmap
2562 * insert tries to happen, instead trimming the LAST
2563 * block from the directory.
2564 */
2565 resblks = XFS_REMOVE_SPACE_RES(mp);
2566 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_remove, resblks, 0, 0, &tp);
2567 if (error == -ENOSPC) {
2568 resblks = 0;
2569 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_remove, 0, 0, 0,
2570 &tp);
2571 }
2572 if (error) {
2573 ASSERT(error != -ENOSPC);
2574 goto std_return;
2575 }
2576
2577 xfs_lock_two_inodes(dp, ip, XFS_ILOCK_EXCL);
2578
2579 xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
2580 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
2581
2582 /*
2583 * If we're removing a directory perform some additional validation.
2584 */
2585 if (is_dir) {
2586 ASSERT(VFS_I(ip)->i_nlink >= 2);
2587 if (VFS_I(ip)->i_nlink != 2) {
2588 error = -ENOTEMPTY;
2589 goto out_trans_cancel;
2590 }
2591 if (!xfs_dir_isempty(ip)) {
2592 error = -ENOTEMPTY;
2593 goto out_trans_cancel;
2594 }
2595
2596 /* Drop the link from ip's "..". */
2597 error = xfs_droplink(tp, dp);
2598 if (error)
2599 goto out_trans_cancel;
2600
2601 /* Drop the "." link from ip to self. */
2602 error = xfs_droplink(tp, ip);
2603 if (error)
2604 goto out_trans_cancel;
2605 } else {
2606 /*
2607 * When removing a non-directory we need to log the parent
2608 * inode here. For a directory this is done implicitly
2609 * by the xfs_droplink call for the ".." entry.
2610 */
2611 xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
2612 }
2613 xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2614
2615 /* Drop the link from dp to ip. */
2616 error = xfs_droplink(tp, ip);
2617 if (error)
2618 goto out_trans_cancel;
2619
2620 xfs_defer_init(&dfops, &first_block);
2621 error = xfs_dir_removename(tp, dp, name, ip->i_ino,
2622 &first_block, &dfops, resblks);
2623 if (error) {
2624 ASSERT(error != -ENOENT);
2625 goto out_bmap_cancel;
2626 }
2627
2628 /*
2629 * If this is a synchronous mount, make sure that the
2630 * remove transaction goes to disk before returning to
2631 * the user.
2632 */
2633 if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
2634 xfs_trans_set_sync(tp);
2635
2636 error = xfs_defer_finish(&tp, &dfops, NULL);
2637 if (error)
2638 goto out_bmap_cancel;
2639
2640 error = xfs_trans_commit(tp);
2641 if (error)
2642 goto std_return;
2643
2644 if (is_dir && xfs_inode_is_filestream(ip))
2645 xfs_filestream_deassociate(ip);
2646
2647 return 0;
2648
2649 out_bmap_cancel:
2650 xfs_defer_cancel(&dfops);
2651 out_trans_cancel:
2652 xfs_trans_cancel(tp);
2653 std_return:
2654 return error;
2655}
2656
2657/*
2658 * Enter all inodes for a rename transaction into a sorted array.
2659 */
2660#define __XFS_SORT_INODES 5
2661STATIC void
2662xfs_sort_for_rename(
2663 struct xfs_inode *dp1, /* in: old (source) directory inode */
2664 struct xfs_inode *dp2, /* in: new (target) directory inode */
2665 struct xfs_inode *ip1, /* in: inode of old entry */
2666 struct xfs_inode *ip2, /* in: inode of new entry */
2667 struct xfs_inode *wip, /* in: whiteout inode */
2668 struct xfs_inode **i_tab,/* out: sorted array of inodes */
2669 int *num_inodes) /* in/out: inodes in array */
2670{
2671 int i, j;
2672
2673 ASSERT(*num_inodes == __XFS_SORT_INODES);
2674 memset(i_tab, 0, *num_inodes * sizeof(struct xfs_inode *));
2675
2676 /*
2677 * i_tab contains a list of pointers to inodes. We initialize
2678 * the table here & we'll sort it. We will then use it to
2679 * order the acquisition of the inode locks.
2680 *
2681 * Note that the table may contain duplicates. e.g., dp1 == dp2.
2682 */
2683 i = 0;
2684 i_tab[i++] = dp1;
2685 i_tab[i++] = dp2;
2686 i_tab[i++] = ip1;
2687 if (ip2)
2688 i_tab[i++] = ip2;
2689 if (wip)
2690 i_tab[i++] = wip;
2691 *num_inodes = i;
2692
2693 /*
2694 * Sort the elements via bubble sort. (Remember, there are at
2695 * most 5 elements to sort, so this is adequate.)
2696 */
2697 for (i = 0; i < *num_inodes; i++) {
2698 for (j = 1; j < *num_inodes; j++) {
2699 if (i_tab[j]->i_ino < i_tab[j-1]->i_ino) {
2700 struct xfs_inode *temp = i_tab[j];
2701 i_tab[j] = i_tab[j-1];
2702 i_tab[j-1] = temp;
2703 }
2704 }
2705 }
2706}
2707
2708static int
2709xfs_finish_rename(
2710 struct xfs_trans *tp,
2711 struct xfs_defer_ops *dfops)
2712{
2713 int error;
2714
2715 /*
2716 * If this is a synchronous mount, make sure that the rename transaction
2717 * goes to disk before returning to the user.
2718 */
2719 if (tp->t_mountp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
2720 xfs_trans_set_sync(tp);
2721
2722 error = xfs_defer_finish(&tp, dfops, NULL);
2723 if (error) {
2724 xfs_defer_cancel(dfops);
2725 xfs_trans_cancel(tp);
2726 return error;
2727 }
2728
2729 return xfs_trans_commit(tp);
2730}
2731
2732/*
2733 * xfs_cross_rename()
2734 *
2735 * responsible for handling RENAME_EXCHANGE flag in renameat2() sytemcall
2736 */
2737STATIC int
2738xfs_cross_rename(
2739 struct xfs_trans *tp,
2740 struct xfs_inode *dp1,
2741 struct xfs_name *name1,
2742 struct xfs_inode *ip1,
2743 struct xfs_inode *dp2,
2744 struct xfs_name *name2,
2745 struct xfs_inode *ip2,
2746 struct xfs_defer_ops *dfops,
2747 xfs_fsblock_t *first_block,
2748 int spaceres)
2749{
2750 int error = 0;
2751 int ip1_flags = 0;
2752 int ip2_flags = 0;
2753 int dp2_flags = 0;
2754
2755 /* Swap inode number for dirent in first parent */
2756 error = xfs_dir_replace(tp, dp1, name1,
2757 ip2->i_ino,
2758 first_block, dfops, spaceres);
2759 if (error)
2760 goto out_trans_abort;
2761
2762 /* Swap inode number for dirent in second parent */
2763 error = xfs_dir_replace(tp, dp2, name2,
2764 ip1->i_ino,
2765 first_block, dfops, spaceres);
2766 if (error)
2767 goto out_trans_abort;
2768
2769 /*
2770 * If we're renaming one or more directories across different parents,
2771 * update the respective ".." entries (and link counts) to match the new
2772 * parents.
2773 */
2774 if (dp1 != dp2) {
2775 dp2_flags = XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
2776
2777 if (S_ISDIR(VFS_I(ip2)->i_mode)) {
2778 error = xfs_dir_replace(tp, ip2, &xfs_name_dotdot,
2779 dp1->i_ino, first_block,
2780 dfops, spaceres);
2781 if (error)
2782 goto out_trans_abort;
2783
2784 /* transfer ip2 ".." reference to dp1 */
2785 if (!S_ISDIR(VFS_I(ip1)->i_mode)) {
2786 error = xfs_droplink(tp, dp2);
2787 if (error)
2788 goto out_trans_abort;
2789 error = xfs_bumplink(tp, dp1);
2790 if (error)
2791 goto out_trans_abort;
2792 }
2793
2794 /*
2795 * Although ip1 isn't changed here, userspace needs
2796 * to be warned about the change, so that applications
2797 * relying on it (like backup ones), will properly
2798 * notify the change
2799 */
2800 ip1_flags |= XFS_ICHGTIME_CHG;
2801 ip2_flags |= XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
2802 }
2803
2804 if (S_ISDIR(VFS_I(ip1)->i_mode)) {
2805 error = xfs_dir_replace(tp, ip1, &xfs_name_dotdot,
2806 dp2->i_ino, first_block,
2807 dfops, spaceres);
2808 if (error)
2809 goto out_trans_abort;
2810
2811 /* transfer ip1 ".." reference to dp2 */
2812 if (!S_ISDIR(VFS_I(ip2)->i_mode)) {
2813 error = xfs_droplink(tp, dp1);
2814 if (error)
2815 goto out_trans_abort;
2816 error = xfs_bumplink(tp, dp2);
2817 if (error)
2818 goto out_trans_abort;
2819 }
2820
2821 /*
2822 * Although ip2 isn't changed here, userspace needs
2823 * to be warned about the change, so that applications
2824 * relying on it (like backup ones), will properly
2825 * notify the change
2826 */
2827 ip1_flags |= XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
2828 ip2_flags |= XFS_ICHGTIME_CHG;
2829 }
2830 }
2831
2832 if (ip1_flags) {
2833 xfs_trans_ichgtime(tp, ip1, ip1_flags);
2834 xfs_trans_log_inode(tp, ip1, XFS_ILOG_CORE);
2835 }
2836 if (ip2_flags) {
2837 xfs_trans_ichgtime(tp, ip2, ip2_flags);
2838 xfs_trans_log_inode(tp, ip2, XFS_ILOG_CORE);
2839 }
2840 if (dp2_flags) {
2841 xfs_trans_ichgtime(tp, dp2, dp2_flags);
2842 xfs_trans_log_inode(tp, dp2, XFS_ILOG_CORE);
2843 }
2844 xfs_trans_ichgtime(tp, dp1, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2845 xfs_trans_log_inode(tp, dp1, XFS_ILOG_CORE);
2846 return xfs_finish_rename(tp, dfops);
2847
2848out_trans_abort:
2849 xfs_defer_cancel(dfops);
2850 xfs_trans_cancel(tp);
2851 return error;
2852}
2853
2854/*
2855 * xfs_rename_alloc_whiteout()
2856 *
2857 * Return a referenced, unlinked, unlocked inode that that can be used as a
2858 * whiteout in a rename transaction. We use a tmpfile inode here so that if we
2859 * crash between allocating the inode and linking it into the rename transaction
2860 * recovery will free the inode and we won't leak it.
2861 */
2862static int
2863xfs_rename_alloc_whiteout(
2864 struct xfs_inode *dp,
2865 struct xfs_inode **wip)
2866{
2867 struct xfs_inode *tmpfile;
2868 int error;
2869
2870 error = xfs_create_tmpfile(dp, NULL, S_IFCHR | WHITEOUT_MODE, &tmpfile);
2871 if (error)
2872 return error;
2873
2874 /*
2875 * Prepare the tmpfile inode as if it were created through the VFS.
2876 * Otherwise, the link increment paths will complain about nlink 0->1.
2877 * Drop the link count as done by d_tmpfile(), complete the inode setup
2878 * and flag it as linkable.
2879 */
2880 drop_nlink(VFS_I(tmpfile));
2881 xfs_setup_iops(tmpfile);
2882 xfs_finish_inode_setup(tmpfile);
2883 VFS_I(tmpfile)->i_state |= I_LINKABLE;
2884
2885 *wip = tmpfile;
2886 return 0;
2887}
2888
2889/*
2890 * xfs_rename
2891 */
2892int
2893xfs_rename(
2894 struct xfs_inode *src_dp,
2895 struct xfs_name *src_name,
2896 struct xfs_inode *src_ip,
2897 struct xfs_inode *target_dp,
2898 struct xfs_name *target_name,
2899 struct xfs_inode *target_ip,
2900 unsigned int flags)
2901{
2902 struct xfs_mount *mp = src_dp->i_mount;
2903 struct xfs_trans *tp;
2904 struct xfs_defer_ops dfops;
2905 xfs_fsblock_t first_block;
2906 struct xfs_inode *wip = NULL; /* whiteout inode */
2907 struct xfs_inode *inodes[__XFS_SORT_INODES];
2908 int num_inodes = __XFS_SORT_INODES;
2909 bool new_parent = (src_dp != target_dp);
2910 bool src_is_directory = S_ISDIR(VFS_I(src_ip)->i_mode);
2911 int spaceres;
2912 int error;
2913
2914 trace_xfs_rename(src_dp, target_dp, src_name, target_name);
2915
2916 if ((flags & RENAME_EXCHANGE) && !target_ip)
2917 return -EINVAL;
2918
2919 /*
2920 * If we are doing a whiteout operation, allocate the whiteout inode
2921 * we will be placing at the target and ensure the type is set
2922 * appropriately.
2923 */
2924 if (flags & RENAME_WHITEOUT) {
2925 ASSERT(!(flags & (RENAME_NOREPLACE | RENAME_EXCHANGE)));
2926 error = xfs_rename_alloc_whiteout(target_dp, &wip);
2927 if (error)
2928 return error;
2929
2930 /* setup target dirent info as whiteout */
2931 src_name->type = XFS_DIR3_FT_CHRDEV;
2932 }
2933
2934 xfs_sort_for_rename(src_dp, target_dp, src_ip, target_ip, wip,
2935 inodes, &num_inodes);
2936
2937 spaceres = XFS_RENAME_SPACE_RES(mp, target_name->len);
2938 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_rename, spaceres, 0, 0, &tp);
2939 if (error == -ENOSPC) {
2940 spaceres = 0;
2941 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_rename, 0, 0, 0,
2942 &tp);
2943 }
2944 if (error)
2945 goto out_release_wip;
2946
2947 /*
2948 * Attach the dquots to the inodes
2949 */
2950 error = xfs_qm_vop_rename_dqattach(inodes);
2951 if (error)
2952 goto out_trans_cancel;
2953
2954 /*
2955 * Lock all the participating inodes. Depending upon whether
2956 * the target_name exists in the target directory, and
2957 * whether the target directory is the same as the source
2958 * directory, we can lock from 2 to 4 inodes.
2959 */
2960 xfs_lock_inodes(inodes, num_inodes, XFS_ILOCK_EXCL);
2961
2962 /*
2963 * Join all the inodes to the transaction. From this point on,
2964 * we can rely on either trans_commit or trans_cancel to unlock
2965 * them.
2966 */
2967 xfs_trans_ijoin(tp, src_dp, XFS_ILOCK_EXCL);
2968 if (new_parent)
2969 xfs_trans_ijoin(tp, target_dp, XFS_ILOCK_EXCL);
2970 xfs_trans_ijoin(tp, src_ip, XFS_ILOCK_EXCL);
2971 if (target_ip)
2972 xfs_trans_ijoin(tp, target_ip, XFS_ILOCK_EXCL);
2973 if (wip)
2974 xfs_trans_ijoin(tp, wip, XFS_ILOCK_EXCL);
2975
2976 /*
2977 * If we are using project inheritance, we only allow renames
2978 * into our tree when the project IDs are the same; else the
2979 * tree quota mechanism would be circumvented.
2980 */
2981 if (unlikely((target_dp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) &&
2982 (xfs_get_projid(target_dp) != xfs_get_projid(src_ip)))) {
2983 error = -EXDEV;
2984 goto out_trans_cancel;
2985 }
2986
2987 xfs_defer_init(&dfops, &first_block);
2988
2989 /* RENAME_EXCHANGE is unique from here on. */
2990 if (flags & RENAME_EXCHANGE)
2991 return xfs_cross_rename(tp, src_dp, src_name, src_ip,
2992 target_dp, target_name, target_ip,
2993 &dfops, &first_block, spaceres);
2994
2995 /*
2996 * Set up the target.
2997 */
2998 if (target_ip == NULL) {
2999 /*
3000 * If there's no space reservation, check the entry will
3001 * fit before actually inserting it.
3002 */
3003 if (!spaceres) {
3004 error = xfs_dir_canenter(tp, target_dp, target_name);
3005 if (error)
3006 goto out_trans_cancel;
3007 }
3008 /*
3009 * If target does not exist and the rename crosses
3010 * directories, adjust the target directory link count
3011 * to account for the ".." reference from the new entry.
3012 */
3013 error = xfs_dir_createname(tp, target_dp, target_name,
3014 src_ip->i_ino, &first_block,
3015 &dfops, spaceres);
3016 if (error)
3017 goto out_bmap_cancel;
3018
3019 xfs_trans_ichgtime(tp, target_dp,
3020 XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
3021
3022 if (new_parent && src_is_directory) {
3023 error = xfs_bumplink(tp, target_dp);
3024 if (error)
3025 goto out_bmap_cancel;
3026 }
3027 } else { /* target_ip != NULL */
3028 /*
3029 * If target exists and it's a directory, check that both
3030 * target and source are directories and that target can be
3031 * destroyed, or that neither is a directory.
3032 */
3033 if (S_ISDIR(VFS_I(target_ip)->i_mode)) {
3034 /*
3035 * Make sure target dir is empty.
3036 */
3037 if (!(xfs_dir_isempty(target_ip)) ||
3038 (VFS_I(target_ip)->i_nlink > 2)) {
3039 error = -EEXIST;
3040 goto out_trans_cancel;
3041 }
3042 }
3043
3044 /*
3045 * Link the source inode under the target name.
3046 * If the source inode is a directory and we are moving
3047 * it across directories, its ".." entry will be
3048 * inconsistent until we replace that down below.
3049 *
3050 * In case there is already an entry with the same
3051 * name at the destination directory, remove it first.
3052 */
3053 error = xfs_dir_replace(tp, target_dp, target_name,
3054 src_ip->i_ino,
3055 &first_block, &dfops, spaceres);
3056 if (error)
3057 goto out_bmap_cancel;
3058
3059 xfs_trans_ichgtime(tp, target_dp,
3060 XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
3061
3062 /*
3063 * Decrement the link count on the target since the target
3064 * dir no longer points to it.
3065 */
3066 error = xfs_droplink(tp, target_ip);
3067 if (error)
3068 goto out_bmap_cancel;
3069
3070 if (src_is_directory) {
3071 /*
3072 * Drop the link from the old "." entry.
3073 */
3074 error = xfs_droplink(tp, target_ip);
3075 if (error)
3076 goto out_bmap_cancel;
3077 }
3078 } /* target_ip != NULL */
3079
3080 /*
3081 * Remove the source.
3082 */
3083 if (new_parent && src_is_directory) {
3084 /*
3085 * Rewrite the ".." entry to point to the new
3086 * directory.
3087 */
3088 error = xfs_dir_replace(tp, src_ip, &xfs_name_dotdot,
3089 target_dp->i_ino,
3090 &first_block, &dfops, spaceres);
3091 ASSERT(error != -EEXIST);
3092 if (error)
3093 goto out_bmap_cancel;
3094 }
3095
3096 /*
3097 * We always want to hit the ctime on the source inode.
3098 *
3099 * This isn't strictly required by the standards since the source
3100 * inode isn't really being changed, but old unix file systems did
3101 * it and some incremental backup programs won't work without it.
3102 */
3103 xfs_trans_ichgtime(tp, src_ip, XFS_ICHGTIME_CHG);
3104 xfs_trans_log_inode(tp, src_ip, XFS_ILOG_CORE);
3105
3106 /*
3107 * Adjust the link count on src_dp. This is necessary when
3108 * renaming a directory, either within one parent when
3109 * the target existed, or across two parent directories.
3110 */
3111 if (src_is_directory && (new_parent || target_ip != NULL)) {
3112
3113 /*
3114 * Decrement link count on src_directory since the
3115 * entry that's moved no longer points to it.
3116 */
3117 error = xfs_droplink(tp, src_dp);
3118 if (error)
3119 goto out_bmap_cancel;
3120 }
3121
3122 /*
3123 * For whiteouts, we only need to update the source dirent with the
3124 * inode number of the whiteout inode rather than removing it
3125 * altogether.
3126 */
3127 if (wip) {
3128 error = xfs_dir_replace(tp, src_dp, src_name, wip->i_ino,
3129 &first_block, &dfops, spaceres);
3130 } else
3131 error = xfs_dir_removename(tp, src_dp, src_name, src_ip->i_ino,
3132 &first_block, &dfops, spaceres);
3133 if (error)
3134 goto out_bmap_cancel;
3135
3136 /*
3137 * For whiteouts, we need to bump the link count on the whiteout inode.
3138 * This means that failures all the way up to this point leave the inode
3139 * on the unlinked list and so cleanup is a simple matter of dropping
3140 * the remaining reference to it. If we fail here after bumping the link
3141 * count, we're shutting down the filesystem so we'll never see the
3142 * intermediate state on disk.
3143 */
3144 if (wip) {
3145 ASSERT(VFS_I(wip)->i_nlink == 0);
3146 error = xfs_bumplink(tp, wip);
3147 if (error)
3148 goto out_bmap_cancel;
3149 error = xfs_iunlink_remove(tp, wip);
3150 if (error)
3151 goto out_bmap_cancel;
3152 xfs_trans_log_inode(tp, wip, XFS_ILOG_CORE);
3153
3154 /*
3155 * Now we have a real link, clear the "I'm a tmpfile" state
3156 * flag from the inode so it doesn't accidentally get misused in
3157 * future.
3158 */
3159 VFS_I(wip)->i_state &= ~I_LINKABLE;
3160 }
3161
3162 xfs_trans_ichgtime(tp, src_dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
3163 xfs_trans_log_inode(tp, src_dp, XFS_ILOG_CORE);
3164 if (new_parent)
3165 xfs_trans_log_inode(tp, target_dp, XFS_ILOG_CORE);
3166
3167 error = xfs_finish_rename(tp, &dfops);
3168 if (wip)
3169 IRELE(wip);
3170 return error;
3171
3172out_bmap_cancel:
3173 xfs_defer_cancel(&dfops);
3174out_trans_cancel:
3175 xfs_trans_cancel(tp);
3176out_release_wip:
3177 if (wip)
3178 IRELE(wip);
3179 return error;
3180}
3181
3182STATIC int
3183xfs_iflush_cluster(
3184 struct xfs_inode *ip,
3185 struct xfs_buf *bp)
3186{
3187 struct xfs_mount *mp = ip->i_mount;
3188 struct xfs_perag *pag;
3189 unsigned long first_index, mask;
3190 unsigned long inodes_per_cluster;
3191 int cilist_size;
3192 struct xfs_inode **cilist;
3193 struct xfs_inode *cip;
3194 int nr_found;
3195 int clcount = 0;
3196 int bufwasdelwri;
3197 int i;
3198
3199 pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));
3200
3201 inodes_per_cluster = mp->m_inode_cluster_size >> mp->m_sb.sb_inodelog;
3202 cilist_size = inodes_per_cluster * sizeof(xfs_inode_t *);
3203 cilist = kmem_alloc(cilist_size, KM_MAYFAIL|KM_NOFS);
3204 if (!cilist)
3205 goto out_put;
3206
3207 mask = ~(((mp->m_inode_cluster_size >> mp->m_sb.sb_inodelog)) - 1);
3208 first_index = XFS_INO_TO_AGINO(mp, ip->i_ino) & mask;
3209 rcu_read_lock();
3210 /* really need a gang lookup range call here */
3211 nr_found = radix_tree_gang_lookup(&pag->pag_ici_root, (void**)cilist,
3212 first_index, inodes_per_cluster);
3213 if (nr_found == 0)
3214 goto out_free;
3215
3216 for (i = 0; i < nr_found; i++) {
3217 cip = cilist[i];
3218 if (cip == ip)
3219 continue;
3220
3221 /*
3222 * because this is an RCU protected lookup, we could find a
3223 * recently freed or even reallocated inode during the lookup.
3224 * We need to check under the i_flags_lock for a valid inode
3225 * here. Skip it if it is not valid or the wrong inode.
3226 */
3227 spin_lock(&cip->i_flags_lock);
3228 if (!cip->i_ino ||
3229 __xfs_iflags_test(cip, XFS_ISTALE)) {
3230 spin_unlock(&cip->i_flags_lock);
3231 continue;
3232 }
3233
3234 /*
3235 * Once we fall off the end of the cluster, no point checking
3236 * any more inodes in the list because they will also all be
3237 * outside the cluster.
3238 */
3239 if ((XFS_INO_TO_AGINO(mp, cip->i_ino) & mask) != first_index) {
3240 spin_unlock(&cip->i_flags_lock);
3241 break;
3242 }
3243 spin_unlock(&cip->i_flags_lock);
3244
3245 /*
3246 * Do an un-protected check to see if the inode is dirty and
3247 * is a candidate for flushing. These checks will be repeated
3248 * later after the appropriate locks are acquired.
3249 */
3250 if (xfs_inode_clean(cip) && xfs_ipincount(cip) == 0)
3251 continue;
3252
3253 /*
3254 * Try to get locks. If any are unavailable or it is pinned,
3255 * then this inode cannot be flushed and is skipped.
3256 */
3257
3258 if (!xfs_ilock_nowait(cip, XFS_ILOCK_SHARED))
3259 continue;
3260 if (!xfs_iflock_nowait(cip)) {
3261 xfs_iunlock(cip, XFS_ILOCK_SHARED);
3262 continue;
3263 }
3264 if (xfs_ipincount(cip)) {
3265 xfs_ifunlock(cip);
3266 xfs_iunlock(cip, XFS_ILOCK_SHARED);
3267 continue;
3268 }
3269
3270
3271 /*
3272 * Check the inode number again, just to be certain we are not
3273 * racing with freeing in xfs_reclaim_inode(). See the comments
3274 * in that function for more information as to why the initial
3275 * check is not sufficient.
3276 */
3277 if (!cip->i_ino) {
3278 xfs_ifunlock(cip);
3279 xfs_iunlock(cip, XFS_ILOCK_SHARED);
3280 continue;
3281 }
3282
3283 /*
3284 * arriving here means that this inode can be flushed. First
3285 * re-check that it's dirty before flushing.
3286 */
3287 if (!xfs_inode_clean(cip)) {
3288 int error;
3289 error = xfs_iflush_int(cip, bp);
3290 if (error) {
3291 xfs_iunlock(cip, XFS_ILOCK_SHARED);
3292 goto cluster_corrupt_out;
3293 }
3294 clcount++;
3295 } else {
3296 xfs_ifunlock(cip);
3297 }
3298 xfs_iunlock(cip, XFS_ILOCK_SHARED);
3299 }
3300
3301 if (clcount) {
3302 XFS_STATS_INC(mp, xs_icluster_flushcnt);
3303 XFS_STATS_ADD(mp, xs_icluster_flushinode, clcount);
3304 }
3305
3306out_free:
3307 rcu_read_unlock();
3308 kmem_free(cilist);
3309out_put:
3310 xfs_perag_put(pag);
3311 return 0;
3312
3313
3314cluster_corrupt_out:
3315 /*
3316 * Corruption detected in the clustering loop. Invalidate the
3317 * inode buffer and shut down the filesystem.
3318 */
3319 rcu_read_unlock();
3320 /*
3321 * Clean up the buffer. If it was delwri, just release it --
3322 * brelse can handle it with no problems. If not, shut down the
3323 * filesystem before releasing the buffer.
3324 */
3325 bufwasdelwri = (bp->b_flags & _XBF_DELWRI_Q);
3326 if (bufwasdelwri)
3327 xfs_buf_relse(bp);
3328
3329 xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
3330
3331 if (!bufwasdelwri) {
3332 /*
3333 * Just like incore_relse: if we have b_iodone functions,
3334 * mark the buffer as an error and call them. Otherwise
3335 * mark it as stale and brelse.
3336 */
3337 if (bp->b_iodone) {
3338 bp->b_flags &= ~XBF_DONE;
3339 xfs_buf_stale(bp);
3340 xfs_buf_ioerror(bp, -EIO);
3341 xfs_buf_ioend(bp);
3342 } else {
3343 xfs_buf_stale(bp);
3344 xfs_buf_relse(bp);
3345 }
3346 }
3347
3348 /*
3349 * Unlocks the flush lock
3350 */
3351 xfs_iflush_abort(cip, false);
3352 kmem_free(cilist);
3353 xfs_perag_put(pag);
3354 return -EFSCORRUPTED;
3355}
3356
3357/*
3358 * Flush dirty inode metadata into the backing buffer.
3359 *
3360 * The caller must have the inode lock and the inode flush lock held. The
3361 * inode lock will still be held upon return to the caller, and the inode
3362 * flush lock will be released after the inode has reached the disk.
3363 *
3364 * The caller must write out the buffer returned in *bpp and release it.
3365 */
3366int
3367xfs_iflush(
3368 struct xfs_inode *ip,
3369 struct xfs_buf **bpp)
3370{
3371 struct xfs_mount *mp = ip->i_mount;
3372 struct xfs_buf *bp = NULL;
3373 struct xfs_dinode *dip;
3374 int error;
3375
3376 XFS_STATS_INC(mp, xs_iflush_count);
3377
3378 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
3379 ASSERT(xfs_isiflocked(ip));
3380 ASSERT(ip->i_d.di_format != XFS_DINODE_FMT_BTREE ||
3381 ip->i_d.di_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK));
3382
3383 *bpp = NULL;
3384
3385 xfs_iunpin_wait(ip);
3386
3387 /*
3388 * For stale inodes we cannot rely on the backing buffer remaining
3389 * stale in cache for the remaining life of the stale inode and so
3390 * xfs_imap_to_bp() below may give us a buffer that no longer contains
3391 * inodes below. We have to check this after ensuring the inode is
3392 * unpinned so that it is safe to reclaim the stale inode after the
3393 * flush call.
3394 */
3395 if (xfs_iflags_test(ip, XFS_ISTALE)) {
3396 xfs_ifunlock(ip);
3397 return 0;
3398 }
3399
3400 /*
3401 * This may have been unpinned because the filesystem is shutting
3402 * down forcibly. If that's the case we must not write this inode
3403 * to disk, because the log record didn't make it to disk.
3404 *
3405 * We also have to remove the log item from the AIL in this case,
3406 * as we wait for an empty AIL as part of the unmount process.
3407 */
3408 if (XFS_FORCED_SHUTDOWN(mp)) {
3409 error = -EIO;
3410 goto abort_out;
3411 }
3412
3413 /*
3414 * Get the buffer containing the on-disk inode. We are doing a try-lock
3415 * operation here, so we may get an EAGAIN error. In that case, we
3416 * simply want to return with the inode still dirty.
3417 *
3418 * If we get any other error, we effectively have a corruption situation
3419 * and we cannot flush the inode, so we treat it the same as failing
3420 * xfs_iflush_int().
3421 */
3422 error = xfs_imap_to_bp(mp, NULL, &ip->i_imap, &dip, &bp, XBF_TRYLOCK,
3423 0);
3424 if (error == -EAGAIN) {
3425 xfs_ifunlock(ip);
3426 return error;
3427 }
3428 if (error)
3429 goto corrupt_out;
3430
3431 /*
3432 * First flush out the inode that xfs_iflush was called with.
3433 */
3434 error = xfs_iflush_int(ip, bp);
3435 if (error)
3436 goto corrupt_out;
3437
3438 /*
3439 * If the buffer is pinned then push on the log now so we won't
3440 * get stuck waiting in the write for too long.
3441 */
3442 if (xfs_buf_ispinned(bp))
3443 xfs_log_force(mp, 0);
3444
3445 /*
3446 * inode clustering:
3447 * see if other inodes can be gathered into this write
3448 */
3449 error = xfs_iflush_cluster(ip, bp);
3450 if (error)
3451 goto cluster_corrupt_out;
3452
3453 *bpp = bp;
3454 return 0;
3455
3456corrupt_out:
3457 if (bp)
3458 xfs_buf_relse(bp);
3459 xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
3460cluster_corrupt_out:
3461 error = -EFSCORRUPTED;
3462abort_out:
3463 /*
3464 * Unlocks the flush lock
3465 */
3466 xfs_iflush_abort(ip, false);
3467 return error;
3468}
3469
3470STATIC int
3471xfs_iflush_int(
3472 struct xfs_inode *ip,
3473 struct xfs_buf *bp)
3474{
3475 struct xfs_inode_log_item *iip = ip->i_itemp;
3476 struct xfs_dinode *dip;
3477 struct xfs_mount *mp = ip->i_mount;
3478
3479 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
3480 ASSERT(xfs_isiflocked(ip));
3481 ASSERT(ip->i_d.di_format != XFS_DINODE_FMT_BTREE ||
3482 ip->i_d.di_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK));
3483 ASSERT(iip != NULL && iip->ili_fields != 0);
3484 ASSERT(ip->i_d.di_version > 1);
3485
3486 /* set *dip = inode's place in the buffer */
3487 dip = xfs_buf_offset(bp, ip->i_imap.im_boffset);
3488
3489 if (XFS_TEST_ERROR(dip->di_magic != cpu_to_be16(XFS_DINODE_MAGIC),
3490 mp, XFS_ERRTAG_IFLUSH_1, XFS_RANDOM_IFLUSH_1)) {
3491 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3492 "%s: Bad inode %Lu magic number 0x%x, ptr 0x%p",
3493 __func__, ip->i_ino, be16_to_cpu(dip->di_magic), dip);
3494 goto corrupt_out;
3495 }
3496 if (S_ISREG(VFS_I(ip)->i_mode)) {
3497 if (XFS_TEST_ERROR(
3498 (ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS) &&
3499 (ip->i_d.di_format != XFS_DINODE_FMT_BTREE),
3500 mp, XFS_ERRTAG_IFLUSH_3, XFS_RANDOM_IFLUSH_3)) {
3501 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3502 "%s: Bad regular inode %Lu, ptr 0x%p",
3503 __func__, ip->i_ino, ip);
3504 goto corrupt_out;
3505 }
3506 } else if (S_ISDIR(VFS_I(ip)->i_mode)) {
3507 if (XFS_TEST_ERROR(
3508 (ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS) &&
3509 (ip->i_d.di_format != XFS_DINODE_FMT_BTREE) &&
3510 (ip->i_d.di_format != XFS_DINODE_FMT_LOCAL),
3511 mp, XFS_ERRTAG_IFLUSH_4, XFS_RANDOM_IFLUSH_4)) {
3512 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3513 "%s: Bad directory inode %Lu, ptr 0x%p",
3514 __func__, ip->i_ino, ip);
3515 goto corrupt_out;
3516 }
3517 }
3518 if (XFS_TEST_ERROR(ip->i_d.di_nextents + ip->i_d.di_anextents >
3519 ip->i_d.di_nblocks, mp, XFS_ERRTAG_IFLUSH_5,
3520 XFS_RANDOM_IFLUSH_5)) {
3521 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3522 "%s: detected corrupt incore inode %Lu, "
3523 "total extents = %d, nblocks = %Ld, ptr 0x%p",
3524 __func__, ip->i_ino,
3525 ip->i_d.di_nextents + ip->i_d.di_anextents,
3526 ip->i_d.di_nblocks, ip);
3527 goto corrupt_out;
3528 }
3529 if (XFS_TEST_ERROR(ip->i_d.di_forkoff > mp->m_sb.sb_inodesize,
3530 mp, XFS_ERRTAG_IFLUSH_6, XFS_RANDOM_IFLUSH_6)) {
3531 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3532 "%s: bad inode %Lu, forkoff 0x%x, ptr 0x%p",
3533 __func__, ip->i_ino, ip->i_d.di_forkoff, ip);
3534 goto corrupt_out;
3535 }
3536
3537 /*
3538 * Inode item log recovery for v2 inodes are dependent on the
3539 * di_flushiter count for correct sequencing. We bump the flush
3540 * iteration count so we can detect flushes which postdate a log record
3541 * during recovery. This is redundant as we now log every change and
3542 * hence this can't happen but we need to still do it to ensure
3543 * backwards compatibility with old kernels that predate logging all
3544 * inode changes.
3545 */
3546 if (ip->i_d.di_version < 3)
3547 ip->i_d.di_flushiter++;
3548
3549 /*
3550 * Copy the dirty parts of the inode into the on-disk inode. We always
3551 * copy out the core of the inode, because if the inode is dirty at all
3552 * the core must be.
3553 */
3554 xfs_inode_to_disk(ip, dip, iip->ili_item.li_lsn);
3555
3556 /* Wrap, we never let the log put out DI_MAX_FLUSH */
3557 if (ip->i_d.di_flushiter == DI_MAX_FLUSH)
3558 ip->i_d.di_flushiter = 0;
3559
3560 xfs_iflush_fork(ip, dip, iip, XFS_DATA_FORK);
3561 if (XFS_IFORK_Q(ip))
3562 xfs_iflush_fork(ip, dip, iip, XFS_ATTR_FORK);
3563 xfs_inobp_check(mp, bp);
3564
3565 /*
3566 * We've recorded everything logged in the inode, so we'd like to clear
3567 * the ili_fields bits so we don't log and flush things unnecessarily.
3568 * However, we can't stop logging all this information until the data
3569 * we've copied into the disk buffer is written to disk. If we did we
3570 * might overwrite the copy of the inode in the log with all the data
3571 * after re-logging only part of it, and in the face of a crash we
3572 * wouldn't have all the data we need to recover.
3573 *
3574 * What we do is move the bits to the ili_last_fields field. When
3575 * logging the inode, these bits are moved back to the ili_fields field.
3576 * In the xfs_iflush_done() routine we clear ili_last_fields, since we
3577 * know that the information those bits represent is permanently on
3578 * disk. As long as the flush completes before the inode is logged
3579 * again, then both ili_fields and ili_last_fields will be cleared.
3580 *
3581 * We can play with the ili_fields bits here, because the inode lock
3582 * must be held exclusively in order to set bits there and the flush
3583 * lock protects the ili_last_fields bits. Set ili_logged so the flush
3584 * done routine can tell whether or not to look in the AIL. Also, store
3585 * the current LSN of the inode so that we can tell whether the item has
3586 * moved in the AIL from xfs_iflush_done(). In order to read the lsn we
3587 * need the AIL lock, because it is a 64 bit value that cannot be read
3588 * atomically.
3589 */
3590 iip->ili_last_fields = iip->ili_fields;
3591 iip->ili_fields = 0;
3592 iip->ili_fsync_fields = 0;
3593 iip->ili_logged = 1;
3594
3595 xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn,
3596 &iip->ili_item.li_lsn);
3597
3598 /*
3599 * Attach the function xfs_iflush_done to the inode's
3600 * buffer. This will remove the inode from the AIL
3601 * and unlock the inode's flush lock when the inode is
3602 * completely written to disk.
3603 */
3604 xfs_buf_attach_iodone(bp, xfs_iflush_done, &iip->ili_item);
3605
3606 /* generate the checksum. */
3607 xfs_dinode_calc_crc(mp, dip);
3608
3609 ASSERT(bp->b_fspriv != NULL);
3610 ASSERT(bp->b_iodone != NULL);
3611 return 0;
3612
3613corrupt_out:
3614 return -EFSCORRUPTED;
3615}
1/*
2 * Copyright (c) 2000-2006 Silicon Graphics, Inc.
3 * All Rights Reserved.
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it would be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
17 */
18#include <linux/log2.h>
19#include <linux/iversion.h>
20
21#include "xfs.h"
22#include "xfs_fs.h"
23#include "xfs_shared.h"
24#include "xfs_format.h"
25#include "xfs_log_format.h"
26#include "xfs_trans_resv.h"
27#include "xfs_sb.h"
28#include "xfs_mount.h"
29#include "xfs_defer.h"
30#include "xfs_inode.h"
31#include "xfs_da_format.h"
32#include "xfs_da_btree.h"
33#include "xfs_dir2.h"
34#include "xfs_attr_sf.h"
35#include "xfs_attr.h"
36#include "xfs_trans_space.h"
37#include "xfs_trans.h"
38#include "xfs_buf_item.h"
39#include "xfs_inode_item.h"
40#include "xfs_ialloc.h"
41#include "xfs_bmap.h"
42#include "xfs_bmap_util.h"
43#include "xfs_errortag.h"
44#include "xfs_error.h"
45#include "xfs_quota.h"
46#include "xfs_filestream.h"
47#include "xfs_cksum.h"
48#include "xfs_trace.h"
49#include "xfs_icache.h"
50#include "xfs_symlink.h"
51#include "xfs_trans_priv.h"
52#include "xfs_log.h"
53#include "xfs_bmap_btree.h"
54#include "xfs_reflink.h"
55#include "xfs_dir2_priv.h"
56
57kmem_zone_t *xfs_inode_zone;
58
59/*
60 * Used in xfs_itruncate_extents(). This is the maximum number of extents
61 * freed from a file in a single transaction.
62 */
63#define XFS_ITRUNC_MAX_EXTENTS 2
64
65STATIC int xfs_iflush_int(struct xfs_inode *, struct xfs_buf *);
66STATIC int xfs_iunlink(struct xfs_trans *, struct xfs_inode *);
67STATIC int xfs_iunlink_remove(struct xfs_trans *, struct xfs_inode *);
68
69/*
70 * helper function to extract extent size hint from inode
71 */
72xfs_extlen_t
73xfs_get_extsz_hint(
74 struct xfs_inode *ip)
75{
76 if ((ip->i_d.di_flags & XFS_DIFLAG_EXTSIZE) && ip->i_d.di_extsize)
77 return ip->i_d.di_extsize;
78 if (XFS_IS_REALTIME_INODE(ip))
79 return ip->i_mount->m_sb.sb_rextsize;
80 return 0;
81}
82
83/*
84 * Helper function to extract CoW extent size hint from inode.
85 * Between the extent size hint and the CoW extent size hint, we
86 * return the greater of the two. If the value is zero (automatic),
87 * use the default size.
88 */
89xfs_extlen_t
90xfs_get_cowextsz_hint(
91 struct xfs_inode *ip)
92{
93 xfs_extlen_t a, b;
94
95 a = 0;
96 if (ip->i_d.di_flags2 & XFS_DIFLAG2_COWEXTSIZE)
97 a = ip->i_d.di_cowextsize;
98 b = xfs_get_extsz_hint(ip);
99
100 a = max(a, b);
101 if (a == 0)
102 return XFS_DEFAULT_COWEXTSZ_HINT;
103 return a;
104}
105
106/*
107 * These two are wrapper routines around the xfs_ilock() routine used to
108 * centralize some grungy code. They are used in places that wish to lock the
109 * inode solely for reading the extents. The reason these places can't just
110 * call xfs_ilock(ip, XFS_ILOCK_SHARED) is that the inode lock also guards to
111 * bringing in of the extents from disk for a file in b-tree format. If the
112 * inode is in b-tree format, then we need to lock the inode exclusively until
113 * the extents are read in. Locking it exclusively all the time would limit
114 * our parallelism unnecessarily, though. What we do instead is check to see
115 * if the extents have been read in yet, and only lock the inode exclusively
116 * if they have not.
117 *
118 * The functions return a value which should be given to the corresponding
119 * xfs_iunlock() call.
120 */
121uint
122xfs_ilock_data_map_shared(
123 struct xfs_inode *ip)
124{
125 uint lock_mode = XFS_ILOCK_SHARED;
126
127 if (ip->i_d.di_format == XFS_DINODE_FMT_BTREE &&
128 (ip->i_df.if_flags & XFS_IFEXTENTS) == 0)
129 lock_mode = XFS_ILOCK_EXCL;
130 xfs_ilock(ip, lock_mode);
131 return lock_mode;
132}
133
134uint
135xfs_ilock_attr_map_shared(
136 struct xfs_inode *ip)
137{
138 uint lock_mode = XFS_ILOCK_SHARED;
139
140 if (ip->i_d.di_aformat == XFS_DINODE_FMT_BTREE &&
141 (ip->i_afp->if_flags & XFS_IFEXTENTS) == 0)
142 lock_mode = XFS_ILOCK_EXCL;
143 xfs_ilock(ip, lock_mode);
144 return lock_mode;
145}
146
147/*
148 * In addition to i_rwsem in the VFS inode, the xfs inode contains 2
149 * multi-reader locks: i_mmap_lock and the i_lock. This routine allows
150 * various combinations of the locks to be obtained.
151 *
152 * The 3 locks should always be ordered so that the IO lock is obtained first,
153 * the mmap lock second and the ilock last in order to prevent deadlock.
154 *
155 * Basic locking order:
156 *
157 * i_rwsem -> i_mmap_lock -> page_lock -> i_ilock
158 *
159 * mmap_sem locking order:
160 *
161 * i_rwsem -> page lock -> mmap_sem
162 * mmap_sem -> i_mmap_lock -> page_lock
163 *
164 * The difference in mmap_sem locking order mean that we cannot hold the
165 * i_mmap_lock over syscall based read(2)/write(2) based IO. These IO paths can
166 * fault in pages during copy in/out (for buffered IO) or require the mmap_sem
167 * in get_user_pages() to map the user pages into the kernel address space for
168 * direct IO. Similarly the i_rwsem cannot be taken inside a page fault because
169 * page faults already hold the mmap_sem.
170 *
171 * Hence to serialise fully against both syscall and mmap based IO, we need to
172 * take both the i_rwsem and the i_mmap_lock. These locks should *only* be both
173 * taken in places where we need to invalidate the page cache in a race
174 * free manner (e.g. truncate, hole punch and other extent manipulation
175 * functions).
176 */
177void
178xfs_ilock(
179 xfs_inode_t *ip,
180 uint lock_flags)
181{
182 trace_xfs_ilock(ip, lock_flags, _RET_IP_);
183
184 /*
185 * You can't set both SHARED and EXCL for the same lock,
186 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
187 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
188 */
189 ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
190 (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
191 ASSERT((lock_flags & (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)) !=
192 (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL));
193 ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
194 (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
195 ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0);
196
197 if (lock_flags & XFS_IOLOCK_EXCL) {
198 down_write_nested(&VFS_I(ip)->i_rwsem,
199 XFS_IOLOCK_DEP(lock_flags));
200 } else if (lock_flags & XFS_IOLOCK_SHARED) {
201 down_read_nested(&VFS_I(ip)->i_rwsem,
202 XFS_IOLOCK_DEP(lock_flags));
203 }
204
205 if (lock_flags & XFS_MMAPLOCK_EXCL)
206 mrupdate_nested(&ip->i_mmaplock, XFS_MMAPLOCK_DEP(lock_flags));
207 else if (lock_flags & XFS_MMAPLOCK_SHARED)
208 mraccess_nested(&ip->i_mmaplock, XFS_MMAPLOCK_DEP(lock_flags));
209
210 if (lock_flags & XFS_ILOCK_EXCL)
211 mrupdate_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
212 else if (lock_flags & XFS_ILOCK_SHARED)
213 mraccess_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
214}
215
216/*
217 * This is just like xfs_ilock(), except that the caller
218 * is guaranteed not to sleep. It returns 1 if it gets
219 * the requested locks and 0 otherwise. If the IO lock is
220 * obtained but the inode lock cannot be, then the IO lock
221 * is dropped before returning.
222 *
223 * ip -- the inode being locked
224 * lock_flags -- this parameter indicates the inode's locks to be
225 * to be locked. See the comment for xfs_ilock() for a list
226 * of valid values.
227 */
228int
229xfs_ilock_nowait(
230 xfs_inode_t *ip,
231 uint lock_flags)
232{
233 trace_xfs_ilock_nowait(ip, lock_flags, _RET_IP_);
234
235 /*
236 * You can't set both SHARED and EXCL for the same lock,
237 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
238 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
239 */
240 ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
241 (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
242 ASSERT((lock_flags & (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)) !=
243 (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL));
244 ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
245 (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
246 ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0);
247
248 if (lock_flags & XFS_IOLOCK_EXCL) {
249 if (!down_write_trylock(&VFS_I(ip)->i_rwsem))
250 goto out;
251 } else if (lock_flags & XFS_IOLOCK_SHARED) {
252 if (!down_read_trylock(&VFS_I(ip)->i_rwsem))
253 goto out;
254 }
255
256 if (lock_flags & XFS_MMAPLOCK_EXCL) {
257 if (!mrtryupdate(&ip->i_mmaplock))
258 goto out_undo_iolock;
259 } else if (lock_flags & XFS_MMAPLOCK_SHARED) {
260 if (!mrtryaccess(&ip->i_mmaplock))
261 goto out_undo_iolock;
262 }
263
264 if (lock_flags & XFS_ILOCK_EXCL) {
265 if (!mrtryupdate(&ip->i_lock))
266 goto out_undo_mmaplock;
267 } else if (lock_flags & XFS_ILOCK_SHARED) {
268 if (!mrtryaccess(&ip->i_lock))
269 goto out_undo_mmaplock;
270 }
271 return 1;
272
273out_undo_mmaplock:
274 if (lock_flags & XFS_MMAPLOCK_EXCL)
275 mrunlock_excl(&ip->i_mmaplock);
276 else if (lock_flags & XFS_MMAPLOCK_SHARED)
277 mrunlock_shared(&ip->i_mmaplock);
278out_undo_iolock:
279 if (lock_flags & XFS_IOLOCK_EXCL)
280 up_write(&VFS_I(ip)->i_rwsem);
281 else if (lock_flags & XFS_IOLOCK_SHARED)
282 up_read(&VFS_I(ip)->i_rwsem);
283out:
284 return 0;
285}
286
287/*
288 * xfs_iunlock() is used to drop the inode locks acquired with
289 * xfs_ilock() and xfs_ilock_nowait(). The caller must pass
290 * in the flags given to xfs_ilock() or xfs_ilock_nowait() so
291 * that we know which locks to drop.
292 *
293 * ip -- the inode being unlocked
294 * lock_flags -- this parameter indicates the inode's locks to be
295 * to be unlocked. See the comment for xfs_ilock() for a list
296 * of valid values for this parameter.
297 *
298 */
299void
300xfs_iunlock(
301 xfs_inode_t *ip,
302 uint lock_flags)
303{
304 /*
305 * You can't set both SHARED and EXCL for the same lock,
306 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
307 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
308 */
309 ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
310 (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
311 ASSERT((lock_flags & (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)) !=
312 (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL));
313 ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
314 (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
315 ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0);
316 ASSERT(lock_flags != 0);
317
318 if (lock_flags & XFS_IOLOCK_EXCL)
319 up_write(&VFS_I(ip)->i_rwsem);
320 else if (lock_flags & XFS_IOLOCK_SHARED)
321 up_read(&VFS_I(ip)->i_rwsem);
322
323 if (lock_flags & XFS_MMAPLOCK_EXCL)
324 mrunlock_excl(&ip->i_mmaplock);
325 else if (lock_flags & XFS_MMAPLOCK_SHARED)
326 mrunlock_shared(&ip->i_mmaplock);
327
328 if (lock_flags & XFS_ILOCK_EXCL)
329 mrunlock_excl(&ip->i_lock);
330 else if (lock_flags & XFS_ILOCK_SHARED)
331 mrunlock_shared(&ip->i_lock);
332
333 trace_xfs_iunlock(ip, lock_flags, _RET_IP_);
334}
335
336/*
337 * give up write locks. the i/o lock cannot be held nested
338 * if it is being demoted.
339 */
340void
341xfs_ilock_demote(
342 xfs_inode_t *ip,
343 uint lock_flags)
344{
345 ASSERT(lock_flags & (XFS_IOLOCK_EXCL|XFS_MMAPLOCK_EXCL|XFS_ILOCK_EXCL));
346 ASSERT((lock_flags &
347 ~(XFS_IOLOCK_EXCL|XFS_MMAPLOCK_EXCL|XFS_ILOCK_EXCL)) == 0);
348
349 if (lock_flags & XFS_ILOCK_EXCL)
350 mrdemote(&ip->i_lock);
351 if (lock_flags & XFS_MMAPLOCK_EXCL)
352 mrdemote(&ip->i_mmaplock);
353 if (lock_flags & XFS_IOLOCK_EXCL)
354 downgrade_write(&VFS_I(ip)->i_rwsem);
355
356 trace_xfs_ilock_demote(ip, lock_flags, _RET_IP_);
357}
358
359#if defined(DEBUG) || defined(XFS_WARN)
360int
361xfs_isilocked(
362 xfs_inode_t *ip,
363 uint lock_flags)
364{
365 if (lock_flags & (XFS_ILOCK_EXCL|XFS_ILOCK_SHARED)) {
366 if (!(lock_flags & XFS_ILOCK_SHARED))
367 return !!ip->i_lock.mr_writer;
368 return rwsem_is_locked(&ip->i_lock.mr_lock);
369 }
370
371 if (lock_flags & (XFS_MMAPLOCK_EXCL|XFS_MMAPLOCK_SHARED)) {
372 if (!(lock_flags & XFS_MMAPLOCK_SHARED))
373 return !!ip->i_mmaplock.mr_writer;
374 return rwsem_is_locked(&ip->i_mmaplock.mr_lock);
375 }
376
377 if (lock_flags & (XFS_IOLOCK_EXCL|XFS_IOLOCK_SHARED)) {
378 if (!(lock_flags & XFS_IOLOCK_SHARED))
379 return !debug_locks ||
380 lockdep_is_held_type(&VFS_I(ip)->i_rwsem, 0);
381 return rwsem_is_locked(&VFS_I(ip)->i_rwsem);
382 }
383
384 ASSERT(0);
385 return 0;
386}
387#endif
388
389/*
390 * xfs_lockdep_subclass_ok() is only used in an ASSERT, so is only called when
391 * DEBUG or XFS_WARN is set. And MAX_LOCKDEP_SUBCLASSES is then only defined
392 * when CONFIG_LOCKDEP is set. Hence the complex define below to avoid build
393 * errors and warnings.
394 */
395#if (defined(DEBUG) || defined(XFS_WARN)) && defined(CONFIG_LOCKDEP)
396static bool
397xfs_lockdep_subclass_ok(
398 int subclass)
399{
400 return subclass < MAX_LOCKDEP_SUBCLASSES;
401}
402#else
403#define xfs_lockdep_subclass_ok(subclass) (true)
404#endif
405
406/*
407 * Bump the subclass so xfs_lock_inodes() acquires each lock with a different
408 * value. This can be called for any type of inode lock combination, including
409 * parent locking. Care must be taken to ensure we don't overrun the subclass
410 * storage fields in the class mask we build.
411 */
412static inline int
413xfs_lock_inumorder(int lock_mode, int subclass)
414{
415 int class = 0;
416
417 ASSERT(!(lock_mode & (XFS_ILOCK_PARENT | XFS_ILOCK_RTBITMAP |
418 XFS_ILOCK_RTSUM)));
419 ASSERT(xfs_lockdep_subclass_ok(subclass));
420
421 if (lock_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)) {
422 ASSERT(subclass <= XFS_IOLOCK_MAX_SUBCLASS);
423 class += subclass << XFS_IOLOCK_SHIFT;
424 }
425
426 if (lock_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) {
427 ASSERT(subclass <= XFS_MMAPLOCK_MAX_SUBCLASS);
428 class += subclass << XFS_MMAPLOCK_SHIFT;
429 }
430
431 if (lock_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)) {
432 ASSERT(subclass <= XFS_ILOCK_MAX_SUBCLASS);
433 class += subclass << XFS_ILOCK_SHIFT;
434 }
435
436 return (lock_mode & ~XFS_LOCK_SUBCLASS_MASK) | class;
437}
438
439/*
440 * The following routine will lock n inodes in exclusive mode. We assume the
441 * caller calls us with the inodes in i_ino order.
442 *
443 * We need to detect deadlock where an inode that we lock is in the AIL and we
444 * start waiting for another inode that is locked by a thread in a long running
445 * transaction (such as truncate). This can result in deadlock since the long
446 * running trans might need to wait for the inode we just locked in order to
447 * push the tail and free space in the log.
448 *
449 * xfs_lock_inodes() can only be used to lock one type of lock at a time -
450 * the iolock, the mmaplock or the ilock, but not more than one at a time. If we
451 * lock more than one at a time, lockdep will report false positives saying we
452 * have violated locking orders.
453 */
454static void
455xfs_lock_inodes(
456 xfs_inode_t **ips,
457 int inodes,
458 uint lock_mode)
459{
460 int attempts = 0, i, j, try_lock;
461 xfs_log_item_t *lp;
462
463 /*
464 * Currently supports between 2 and 5 inodes with exclusive locking. We
465 * support an arbitrary depth of locking here, but absolute limits on
466 * inodes depend on the the type of locking and the limits placed by
467 * lockdep annotations in xfs_lock_inumorder. These are all checked by
468 * the asserts.
469 */
470 ASSERT(ips && inodes >= 2 && inodes <= 5);
471 ASSERT(lock_mode & (XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL |
472 XFS_ILOCK_EXCL));
473 ASSERT(!(lock_mode & (XFS_IOLOCK_SHARED | XFS_MMAPLOCK_SHARED |
474 XFS_ILOCK_SHARED)));
475 ASSERT(!(lock_mode & XFS_MMAPLOCK_EXCL) ||
476 inodes <= XFS_MMAPLOCK_MAX_SUBCLASS + 1);
477 ASSERT(!(lock_mode & XFS_ILOCK_EXCL) ||
478 inodes <= XFS_ILOCK_MAX_SUBCLASS + 1);
479
480 if (lock_mode & XFS_IOLOCK_EXCL) {
481 ASSERT(!(lock_mode & (XFS_MMAPLOCK_EXCL | XFS_ILOCK_EXCL)));
482 } else if (lock_mode & XFS_MMAPLOCK_EXCL)
483 ASSERT(!(lock_mode & XFS_ILOCK_EXCL));
484
485 try_lock = 0;
486 i = 0;
487again:
488 for (; i < inodes; i++) {
489 ASSERT(ips[i]);
490
491 if (i && (ips[i] == ips[i - 1])) /* Already locked */
492 continue;
493
494 /*
495 * If try_lock is not set yet, make sure all locked inodes are
496 * not in the AIL. If any are, set try_lock to be used later.
497 */
498 if (!try_lock) {
499 for (j = (i - 1); j >= 0 && !try_lock; j--) {
500 lp = (xfs_log_item_t *)ips[j]->i_itemp;
501 if (lp && (lp->li_flags & XFS_LI_IN_AIL))
502 try_lock++;
503 }
504 }
505
506 /*
507 * If any of the previous locks we have locked is in the AIL,
508 * we must TRY to get the second and subsequent locks. If
509 * we can't get any, we must release all we have
510 * and try again.
511 */
512 if (!try_lock) {
513 xfs_ilock(ips[i], xfs_lock_inumorder(lock_mode, i));
514 continue;
515 }
516
517 /* try_lock means we have an inode locked that is in the AIL. */
518 ASSERT(i != 0);
519 if (xfs_ilock_nowait(ips[i], xfs_lock_inumorder(lock_mode, i)))
520 continue;
521
522 /*
523 * Unlock all previous guys and try again. xfs_iunlock will try
524 * to push the tail if the inode is in the AIL.
525 */
526 attempts++;
527 for (j = i - 1; j >= 0; j--) {
528 /*
529 * Check to see if we've already unlocked this one. Not
530 * the first one going back, and the inode ptr is the
531 * same.
532 */
533 if (j != (i - 1) && ips[j] == ips[j + 1])
534 continue;
535
536 xfs_iunlock(ips[j], lock_mode);
537 }
538
539 if ((attempts % 5) == 0) {
540 delay(1); /* Don't just spin the CPU */
541 }
542 i = 0;
543 try_lock = 0;
544 goto again;
545 }
546}
547
548/*
549 * xfs_lock_two_inodes() can only be used to lock one type of lock at a time -
550 * the mmaplock or the ilock, but not more than one type at a time. If we lock
551 * more than one at a time, lockdep will report false positives saying we have
552 * violated locking orders. The iolock must be double-locked separately since
553 * we use i_rwsem for that. We now support taking one lock EXCL and the other
554 * SHARED.
555 */
556void
557xfs_lock_two_inodes(
558 struct xfs_inode *ip0,
559 uint ip0_mode,
560 struct xfs_inode *ip1,
561 uint ip1_mode)
562{
563 struct xfs_inode *temp;
564 uint mode_temp;
565 int attempts = 0;
566 xfs_log_item_t *lp;
567
568 ASSERT(hweight32(ip0_mode) == 1);
569 ASSERT(hweight32(ip1_mode) == 1);
570 ASSERT(!(ip0_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)));
571 ASSERT(!(ip1_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)));
572 ASSERT(!(ip0_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) ||
573 !(ip0_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)));
574 ASSERT(!(ip1_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) ||
575 !(ip1_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)));
576 ASSERT(!(ip1_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) ||
577 !(ip0_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)));
578 ASSERT(!(ip0_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) ||
579 !(ip1_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)));
580
581 ASSERT(ip0->i_ino != ip1->i_ino);
582
583 if (ip0->i_ino > ip1->i_ino) {
584 temp = ip0;
585 ip0 = ip1;
586 ip1 = temp;
587 mode_temp = ip0_mode;
588 ip0_mode = ip1_mode;
589 ip1_mode = mode_temp;
590 }
591
592 again:
593 xfs_ilock(ip0, xfs_lock_inumorder(ip0_mode, 0));
594
595 /*
596 * If the first lock we have locked is in the AIL, we must TRY to get
597 * the second lock. If we can't get it, we must release the first one
598 * and try again.
599 */
600 lp = (xfs_log_item_t *)ip0->i_itemp;
601 if (lp && (lp->li_flags & XFS_LI_IN_AIL)) {
602 if (!xfs_ilock_nowait(ip1, xfs_lock_inumorder(ip1_mode, 1))) {
603 xfs_iunlock(ip0, ip0_mode);
604 if ((++attempts % 5) == 0)
605 delay(1); /* Don't just spin the CPU */
606 goto again;
607 }
608 } else {
609 xfs_ilock(ip1, xfs_lock_inumorder(ip1_mode, 1));
610 }
611}
612
613void
614__xfs_iflock(
615 struct xfs_inode *ip)
616{
617 wait_queue_head_t *wq = bit_waitqueue(&ip->i_flags, __XFS_IFLOCK_BIT);
618 DEFINE_WAIT_BIT(wait, &ip->i_flags, __XFS_IFLOCK_BIT);
619
620 do {
621 prepare_to_wait_exclusive(wq, &wait.wq_entry, TASK_UNINTERRUPTIBLE);
622 if (xfs_isiflocked(ip))
623 io_schedule();
624 } while (!xfs_iflock_nowait(ip));
625
626 finish_wait(wq, &wait.wq_entry);
627}
628
629STATIC uint
630_xfs_dic2xflags(
631 uint16_t di_flags,
632 uint64_t di_flags2,
633 bool has_attr)
634{
635 uint flags = 0;
636
637 if (di_flags & XFS_DIFLAG_ANY) {
638 if (di_flags & XFS_DIFLAG_REALTIME)
639 flags |= FS_XFLAG_REALTIME;
640 if (di_flags & XFS_DIFLAG_PREALLOC)
641 flags |= FS_XFLAG_PREALLOC;
642 if (di_flags & XFS_DIFLAG_IMMUTABLE)
643 flags |= FS_XFLAG_IMMUTABLE;
644 if (di_flags & XFS_DIFLAG_APPEND)
645 flags |= FS_XFLAG_APPEND;
646 if (di_flags & XFS_DIFLAG_SYNC)
647 flags |= FS_XFLAG_SYNC;
648 if (di_flags & XFS_DIFLAG_NOATIME)
649 flags |= FS_XFLAG_NOATIME;
650 if (di_flags & XFS_DIFLAG_NODUMP)
651 flags |= FS_XFLAG_NODUMP;
652 if (di_flags & XFS_DIFLAG_RTINHERIT)
653 flags |= FS_XFLAG_RTINHERIT;
654 if (di_flags & XFS_DIFLAG_PROJINHERIT)
655 flags |= FS_XFLAG_PROJINHERIT;
656 if (di_flags & XFS_DIFLAG_NOSYMLINKS)
657 flags |= FS_XFLAG_NOSYMLINKS;
658 if (di_flags & XFS_DIFLAG_EXTSIZE)
659 flags |= FS_XFLAG_EXTSIZE;
660 if (di_flags & XFS_DIFLAG_EXTSZINHERIT)
661 flags |= FS_XFLAG_EXTSZINHERIT;
662 if (di_flags & XFS_DIFLAG_NODEFRAG)
663 flags |= FS_XFLAG_NODEFRAG;
664 if (di_flags & XFS_DIFLAG_FILESTREAM)
665 flags |= FS_XFLAG_FILESTREAM;
666 }
667
668 if (di_flags2 & XFS_DIFLAG2_ANY) {
669 if (di_flags2 & XFS_DIFLAG2_DAX)
670 flags |= FS_XFLAG_DAX;
671 if (di_flags2 & XFS_DIFLAG2_COWEXTSIZE)
672 flags |= FS_XFLAG_COWEXTSIZE;
673 }
674
675 if (has_attr)
676 flags |= FS_XFLAG_HASATTR;
677
678 return flags;
679}
680
681uint
682xfs_ip2xflags(
683 struct xfs_inode *ip)
684{
685 struct xfs_icdinode *dic = &ip->i_d;
686
687 return _xfs_dic2xflags(dic->di_flags, dic->di_flags2, XFS_IFORK_Q(ip));
688}
689
690/*
691 * Lookups up an inode from "name". If ci_name is not NULL, then a CI match
692 * is allowed, otherwise it has to be an exact match. If a CI match is found,
693 * ci_name->name will point to a the actual name (caller must free) or
694 * will be set to NULL if an exact match is found.
695 */
696int
697xfs_lookup(
698 xfs_inode_t *dp,
699 struct xfs_name *name,
700 xfs_inode_t **ipp,
701 struct xfs_name *ci_name)
702{
703 xfs_ino_t inum;
704 int error;
705
706 trace_xfs_lookup(dp, name);
707
708 if (XFS_FORCED_SHUTDOWN(dp->i_mount))
709 return -EIO;
710
711 error = xfs_dir_lookup(NULL, dp, name, &inum, ci_name);
712 if (error)
713 goto out_unlock;
714
715 error = xfs_iget(dp->i_mount, NULL, inum, 0, 0, ipp);
716 if (error)
717 goto out_free_name;
718
719 return 0;
720
721out_free_name:
722 if (ci_name)
723 kmem_free(ci_name->name);
724out_unlock:
725 *ipp = NULL;
726 return error;
727}
728
729/*
730 * Allocate an inode on disk and return a copy of its in-core version.
731 * The in-core inode is locked exclusively. Set mode, nlink, and rdev
732 * appropriately within the inode. The uid and gid for the inode are
733 * set according to the contents of the given cred structure.
734 *
735 * Use xfs_dialloc() to allocate the on-disk inode. If xfs_dialloc()
736 * has a free inode available, call xfs_iget() to obtain the in-core
737 * version of the allocated inode. Finally, fill in the inode and
738 * log its initial contents. In this case, ialloc_context would be
739 * set to NULL.
740 *
741 * If xfs_dialloc() does not have an available inode, it will replenish
742 * its supply by doing an allocation. Since we can only do one
743 * allocation within a transaction without deadlocks, we must commit
744 * the current transaction before returning the inode itself.
745 * In this case, therefore, we will set ialloc_context and return.
746 * The caller should then commit the current transaction, start a new
747 * transaction, and call xfs_ialloc() again to actually get the inode.
748 *
749 * To ensure that some other process does not grab the inode that
750 * was allocated during the first call to xfs_ialloc(), this routine
751 * also returns the [locked] bp pointing to the head of the freelist
752 * as ialloc_context. The caller should hold this buffer across
753 * the commit and pass it back into this routine on the second call.
754 *
755 * If we are allocating quota inodes, we do not have a parent inode
756 * to attach to or associate with (i.e. pip == NULL) because they
757 * are not linked into the directory structure - they are attached
758 * directly to the superblock - and so have no parent.
759 */
760static int
761xfs_ialloc(
762 xfs_trans_t *tp,
763 xfs_inode_t *pip,
764 umode_t mode,
765 xfs_nlink_t nlink,
766 dev_t rdev,
767 prid_t prid,
768 xfs_buf_t **ialloc_context,
769 xfs_inode_t **ipp)
770{
771 struct xfs_mount *mp = tp->t_mountp;
772 xfs_ino_t ino;
773 xfs_inode_t *ip;
774 uint flags;
775 int error;
776 struct timespec tv;
777 struct inode *inode;
778
779 /*
780 * Call the space management code to pick
781 * the on-disk inode to be allocated.
782 */
783 error = xfs_dialloc(tp, pip ? pip->i_ino : 0, mode,
784 ialloc_context, &ino);
785 if (error)
786 return error;
787 if (*ialloc_context || ino == NULLFSINO) {
788 *ipp = NULL;
789 return 0;
790 }
791 ASSERT(*ialloc_context == NULL);
792
793 /*
794 * Get the in-core inode with the lock held exclusively.
795 * This is because we're setting fields here we need
796 * to prevent others from looking at until we're done.
797 */
798 error = xfs_iget(mp, tp, ino, XFS_IGET_CREATE,
799 XFS_ILOCK_EXCL, &ip);
800 if (error)
801 return error;
802 ASSERT(ip != NULL);
803 inode = VFS_I(ip);
804
805 /*
806 * We always convert v1 inodes to v2 now - we only support filesystems
807 * with >= v2 inode capability, so there is no reason for ever leaving
808 * an inode in v1 format.
809 */
810 if (ip->i_d.di_version == 1)
811 ip->i_d.di_version = 2;
812
813 inode->i_mode = mode;
814 set_nlink(inode, nlink);
815 ip->i_d.di_uid = xfs_kuid_to_uid(current_fsuid());
816 ip->i_d.di_gid = xfs_kgid_to_gid(current_fsgid());
817 inode->i_rdev = rdev;
818 xfs_set_projid(ip, prid);
819
820 if (pip && XFS_INHERIT_GID(pip)) {
821 ip->i_d.di_gid = pip->i_d.di_gid;
822 if ((VFS_I(pip)->i_mode & S_ISGID) && S_ISDIR(mode))
823 inode->i_mode |= S_ISGID;
824 }
825
826 /*
827 * If the group ID of the new file does not match the effective group
828 * ID or one of the supplementary group IDs, the S_ISGID bit is cleared
829 * (and only if the irix_sgid_inherit compatibility variable is set).
830 */
831 if ((irix_sgid_inherit) &&
832 (inode->i_mode & S_ISGID) &&
833 (!in_group_p(xfs_gid_to_kgid(ip->i_d.di_gid))))
834 inode->i_mode &= ~S_ISGID;
835
836 ip->i_d.di_size = 0;
837 ip->i_d.di_nextents = 0;
838 ASSERT(ip->i_d.di_nblocks == 0);
839
840 tv = current_time(inode);
841 inode->i_mtime = tv;
842 inode->i_atime = tv;
843 inode->i_ctime = tv;
844
845 ip->i_d.di_extsize = 0;
846 ip->i_d.di_dmevmask = 0;
847 ip->i_d.di_dmstate = 0;
848 ip->i_d.di_flags = 0;
849
850 if (ip->i_d.di_version == 3) {
851 inode_set_iversion(inode, 1);
852 ip->i_d.di_flags2 = 0;
853 ip->i_d.di_cowextsize = 0;
854 ip->i_d.di_crtime.t_sec = (int32_t)tv.tv_sec;
855 ip->i_d.di_crtime.t_nsec = (int32_t)tv.tv_nsec;
856 }
857
858
859 flags = XFS_ILOG_CORE;
860 switch (mode & S_IFMT) {
861 case S_IFIFO:
862 case S_IFCHR:
863 case S_IFBLK:
864 case S_IFSOCK:
865 ip->i_d.di_format = XFS_DINODE_FMT_DEV;
866 ip->i_df.if_flags = 0;
867 flags |= XFS_ILOG_DEV;
868 break;
869 case S_IFREG:
870 case S_IFDIR:
871 if (pip && (pip->i_d.di_flags & XFS_DIFLAG_ANY)) {
872 uint di_flags = 0;
873
874 if (S_ISDIR(mode)) {
875 if (pip->i_d.di_flags & XFS_DIFLAG_RTINHERIT)
876 di_flags |= XFS_DIFLAG_RTINHERIT;
877 if (pip->i_d.di_flags & XFS_DIFLAG_EXTSZINHERIT) {
878 di_flags |= XFS_DIFLAG_EXTSZINHERIT;
879 ip->i_d.di_extsize = pip->i_d.di_extsize;
880 }
881 if (pip->i_d.di_flags & XFS_DIFLAG_PROJINHERIT)
882 di_flags |= XFS_DIFLAG_PROJINHERIT;
883 } else if (S_ISREG(mode)) {
884 if (pip->i_d.di_flags & XFS_DIFLAG_RTINHERIT)
885 di_flags |= XFS_DIFLAG_REALTIME;
886 if (pip->i_d.di_flags & XFS_DIFLAG_EXTSZINHERIT) {
887 di_flags |= XFS_DIFLAG_EXTSIZE;
888 ip->i_d.di_extsize = pip->i_d.di_extsize;
889 }
890 }
891 if ((pip->i_d.di_flags & XFS_DIFLAG_NOATIME) &&
892 xfs_inherit_noatime)
893 di_flags |= XFS_DIFLAG_NOATIME;
894 if ((pip->i_d.di_flags & XFS_DIFLAG_NODUMP) &&
895 xfs_inherit_nodump)
896 di_flags |= XFS_DIFLAG_NODUMP;
897 if ((pip->i_d.di_flags & XFS_DIFLAG_SYNC) &&
898 xfs_inherit_sync)
899 di_flags |= XFS_DIFLAG_SYNC;
900 if ((pip->i_d.di_flags & XFS_DIFLAG_NOSYMLINKS) &&
901 xfs_inherit_nosymlinks)
902 di_flags |= XFS_DIFLAG_NOSYMLINKS;
903 if ((pip->i_d.di_flags & XFS_DIFLAG_NODEFRAG) &&
904 xfs_inherit_nodefrag)
905 di_flags |= XFS_DIFLAG_NODEFRAG;
906 if (pip->i_d.di_flags & XFS_DIFLAG_FILESTREAM)
907 di_flags |= XFS_DIFLAG_FILESTREAM;
908
909 ip->i_d.di_flags |= di_flags;
910 }
911 if (pip &&
912 (pip->i_d.di_flags2 & XFS_DIFLAG2_ANY) &&
913 pip->i_d.di_version == 3 &&
914 ip->i_d.di_version == 3) {
915 uint64_t di_flags2 = 0;
916
917 if (pip->i_d.di_flags2 & XFS_DIFLAG2_COWEXTSIZE) {
918 di_flags2 |= XFS_DIFLAG2_COWEXTSIZE;
919 ip->i_d.di_cowextsize = pip->i_d.di_cowextsize;
920 }
921 if (pip->i_d.di_flags2 & XFS_DIFLAG2_DAX)
922 di_flags2 |= XFS_DIFLAG2_DAX;
923
924 ip->i_d.di_flags2 |= di_flags2;
925 }
926 /* FALLTHROUGH */
927 case S_IFLNK:
928 ip->i_d.di_format = XFS_DINODE_FMT_EXTENTS;
929 ip->i_df.if_flags = XFS_IFEXTENTS;
930 ip->i_df.if_bytes = ip->i_df.if_real_bytes = 0;
931 ip->i_df.if_u1.if_root = NULL;
932 break;
933 default:
934 ASSERT(0);
935 }
936 /*
937 * Attribute fork settings for new inode.
938 */
939 ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;
940 ip->i_d.di_anextents = 0;
941
942 /*
943 * Log the new values stuffed into the inode.
944 */
945 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
946 xfs_trans_log_inode(tp, ip, flags);
947
948 /* now that we have an i_mode we can setup the inode structure */
949 xfs_setup_inode(ip);
950
951 *ipp = ip;
952 return 0;
953}
954
955/*
956 * Allocates a new inode from disk and return a pointer to the
957 * incore copy. This routine will internally commit the current
958 * transaction and allocate a new one if the Space Manager needed
959 * to do an allocation to replenish the inode free-list.
960 *
961 * This routine is designed to be called from xfs_create and
962 * xfs_create_dir.
963 *
964 */
965int
966xfs_dir_ialloc(
967 xfs_trans_t **tpp, /* input: current transaction;
968 output: may be a new transaction. */
969 xfs_inode_t *dp, /* directory within whose allocate
970 the inode. */
971 umode_t mode,
972 xfs_nlink_t nlink,
973 dev_t rdev,
974 prid_t prid, /* project id */
975 xfs_inode_t **ipp) /* pointer to inode; it will be
976 locked. */
977{
978 xfs_trans_t *tp;
979 xfs_inode_t *ip;
980 xfs_buf_t *ialloc_context = NULL;
981 int code;
982 void *dqinfo;
983 uint tflags;
984
985 tp = *tpp;
986 ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
987
988 /*
989 * xfs_ialloc will return a pointer to an incore inode if
990 * the Space Manager has an available inode on the free
991 * list. Otherwise, it will do an allocation and replenish
992 * the freelist. Since we can only do one allocation per
993 * transaction without deadlocks, we will need to commit the
994 * current transaction and start a new one. We will then
995 * need to call xfs_ialloc again to get the inode.
996 *
997 * If xfs_ialloc did an allocation to replenish the freelist,
998 * it returns the bp containing the head of the freelist as
999 * ialloc_context. We will hold a lock on it across the
1000 * transaction commit so that no other process can steal
1001 * the inode(s) that we've just allocated.
1002 */
1003 code = xfs_ialloc(tp, dp, mode, nlink, rdev, prid, &ialloc_context,
1004 &ip);
1005
1006 /*
1007 * Return an error if we were unable to allocate a new inode.
1008 * This should only happen if we run out of space on disk or
1009 * encounter a disk error.
1010 */
1011 if (code) {
1012 *ipp = NULL;
1013 return code;
1014 }
1015 if (!ialloc_context && !ip) {
1016 *ipp = NULL;
1017 return -ENOSPC;
1018 }
1019
1020 /*
1021 * If the AGI buffer is non-NULL, then we were unable to get an
1022 * inode in one operation. We need to commit the current
1023 * transaction and call xfs_ialloc() again. It is guaranteed
1024 * to succeed the second time.
1025 */
1026 if (ialloc_context) {
1027 /*
1028 * Normally, xfs_trans_commit releases all the locks.
1029 * We call bhold to hang on to the ialloc_context across
1030 * the commit. Holding this buffer prevents any other
1031 * processes from doing any allocations in this
1032 * allocation group.
1033 */
1034 xfs_trans_bhold(tp, ialloc_context);
1035
1036 /*
1037 * We want the quota changes to be associated with the next
1038 * transaction, NOT this one. So, detach the dqinfo from this
1039 * and attach it to the next transaction.
1040 */
1041 dqinfo = NULL;
1042 tflags = 0;
1043 if (tp->t_dqinfo) {
1044 dqinfo = (void *)tp->t_dqinfo;
1045 tp->t_dqinfo = NULL;
1046 tflags = tp->t_flags & XFS_TRANS_DQ_DIRTY;
1047 tp->t_flags &= ~(XFS_TRANS_DQ_DIRTY);
1048 }
1049
1050 code = xfs_trans_roll(&tp);
1051
1052 /*
1053 * Re-attach the quota info that we detached from prev trx.
1054 */
1055 if (dqinfo) {
1056 tp->t_dqinfo = dqinfo;
1057 tp->t_flags |= tflags;
1058 }
1059
1060 if (code) {
1061 xfs_buf_relse(ialloc_context);
1062 *tpp = tp;
1063 *ipp = NULL;
1064 return code;
1065 }
1066 xfs_trans_bjoin(tp, ialloc_context);
1067
1068 /*
1069 * Call ialloc again. Since we've locked out all
1070 * other allocations in this allocation group,
1071 * this call should always succeed.
1072 */
1073 code = xfs_ialloc(tp, dp, mode, nlink, rdev, prid,
1074 &ialloc_context, &ip);
1075
1076 /*
1077 * If we get an error at this point, return to the caller
1078 * so that the current transaction can be aborted.
1079 */
1080 if (code) {
1081 *tpp = tp;
1082 *ipp = NULL;
1083 return code;
1084 }
1085 ASSERT(!ialloc_context && ip);
1086
1087 }
1088
1089 *ipp = ip;
1090 *tpp = tp;
1091
1092 return 0;
1093}
1094
1095/*
1096 * Decrement the link count on an inode & log the change. If this causes the
1097 * link count to go to zero, move the inode to AGI unlinked list so that it can
1098 * be freed when the last active reference goes away via xfs_inactive().
1099 */
1100static int /* error */
1101xfs_droplink(
1102 xfs_trans_t *tp,
1103 xfs_inode_t *ip)
1104{
1105 xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
1106
1107 drop_nlink(VFS_I(ip));
1108 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1109
1110 if (VFS_I(ip)->i_nlink)
1111 return 0;
1112
1113 return xfs_iunlink(tp, ip);
1114}
1115
1116/*
1117 * Increment the link count on an inode & log the change.
1118 */
1119static int
1120xfs_bumplink(
1121 xfs_trans_t *tp,
1122 xfs_inode_t *ip)
1123{
1124 xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
1125
1126 ASSERT(ip->i_d.di_version > 1);
1127 inc_nlink(VFS_I(ip));
1128 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1129 return 0;
1130}
1131
1132int
1133xfs_create(
1134 xfs_inode_t *dp,
1135 struct xfs_name *name,
1136 umode_t mode,
1137 dev_t rdev,
1138 xfs_inode_t **ipp)
1139{
1140 int is_dir = S_ISDIR(mode);
1141 struct xfs_mount *mp = dp->i_mount;
1142 struct xfs_inode *ip = NULL;
1143 struct xfs_trans *tp = NULL;
1144 int error;
1145 struct xfs_defer_ops dfops;
1146 xfs_fsblock_t first_block;
1147 bool unlock_dp_on_error = false;
1148 prid_t prid;
1149 struct xfs_dquot *udqp = NULL;
1150 struct xfs_dquot *gdqp = NULL;
1151 struct xfs_dquot *pdqp = NULL;
1152 struct xfs_trans_res *tres;
1153 uint resblks;
1154
1155 trace_xfs_create(dp, name);
1156
1157 if (XFS_FORCED_SHUTDOWN(mp))
1158 return -EIO;
1159
1160 prid = xfs_get_initial_prid(dp);
1161
1162 /*
1163 * Make sure that we have allocated dquot(s) on disk.
1164 */
1165 error = xfs_qm_vop_dqalloc(dp, xfs_kuid_to_uid(current_fsuid()),
1166 xfs_kgid_to_gid(current_fsgid()), prid,
1167 XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
1168 &udqp, &gdqp, &pdqp);
1169 if (error)
1170 return error;
1171
1172 if (is_dir) {
1173 resblks = XFS_MKDIR_SPACE_RES(mp, name->len);
1174 tres = &M_RES(mp)->tr_mkdir;
1175 } else {
1176 resblks = XFS_CREATE_SPACE_RES(mp, name->len);
1177 tres = &M_RES(mp)->tr_create;
1178 }
1179
1180 /*
1181 * Initially assume that the file does not exist and
1182 * reserve the resources for that case. If that is not
1183 * the case we'll drop the one we have and get a more
1184 * appropriate transaction later.
1185 */
1186 error = xfs_trans_alloc(mp, tres, resblks, 0, 0, &tp);
1187 if (error == -ENOSPC) {
1188 /* flush outstanding delalloc blocks and retry */
1189 xfs_flush_inodes(mp);
1190 error = xfs_trans_alloc(mp, tres, resblks, 0, 0, &tp);
1191 }
1192 if (error)
1193 goto out_release_inode;
1194
1195 xfs_ilock(dp, XFS_ILOCK_EXCL | XFS_ILOCK_PARENT);
1196 unlock_dp_on_error = true;
1197
1198 xfs_defer_init(&dfops, &first_block);
1199
1200 /*
1201 * Reserve disk quota and the inode.
1202 */
1203 error = xfs_trans_reserve_quota(tp, mp, udqp, gdqp,
1204 pdqp, resblks, 1, 0);
1205 if (error)
1206 goto out_trans_cancel;
1207
1208 /*
1209 * A newly created regular or special file just has one directory
1210 * entry pointing to them, but a directory also the "." entry
1211 * pointing to itself.
1212 */
1213 error = xfs_dir_ialloc(&tp, dp, mode, is_dir ? 2 : 1, rdev, prid, &ip);
1214 if (error)
1215 goto out_trans_cancel;
1216
1217 /*
1218 * Now we join the directory inode to the transaction. We do not do it
1219 * earlier because xfs_dir_ialloc might commit the previous transaction
1220 * (and release all the locks). An error from here on will result in
1221 * the transaction cancel unlocking dp so don't do it explicitly in the
1222 * error path.
1223 */
1224 xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
1225 unlock_dp_on_error = false;
1226
1227 error = xfs_dir_createname(tp, dp, name, ip->i_ino,
1228 &first_block, &dfops, resblks ?
1229 resblks - XFS_IALLOC_SPACE_RES(mp) : 0);
1230 if (error) {
1231 ASSERT(error != -ENOSPC);
1232 goto out_trans_cancel;
1233 }
1234 xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1235 xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
1236
1237 if (is_dir) {
1238 error = xfs_dir_init(tp, ip, dp);
1239 if (error)
1240 goto out_bmap_cancel;
1241
1242 error = xfs_bumplink(tp, dp);
1243 if (error)
1244 goto out_bmap_cancel;
1245 }
1246
1247 /*
1248 * If this is a synchronous mount, make sure that the
1249 * create transaction goes to disk before returning to
1250 * the user.
1251 */
1252 if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
1253 xfs_trans_set_sync(tp);
1254
1255 /*
1256 * Attach the dquot(s) to the inodes and modify them incore.
1257 * These ids of the inode couldn't have changed since the new
1258 * inode has been locked ever since it was created.
1259 */
1260 xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp, pdqp);
1261
1262 error = xfs_defer_finish(&tp, &dfops);
1263 if (error)
1264 goto out_bmap_cancel;
1265
1266 error = xfs_trans_commit(tp);
1267 if (error)
1268 goto out_release_inode;
1269
1270 xfs_qm_dqrele(udqp);
1271 xfs_qm_dqrele(gdqp);
1272 xfs_qm_dqrele(pdqp);
1273
1274 *ipp = ip;
1275 return 0;
1276
1277 out_bmap_cancel:
1278 xfs_defer_cancel(&dfops);
1279 out_trans_cancel:
1280 xfs_trans_cancel(tp);
1281 out_release_inode:
1282 /*
1283 * Wait until after the current transaction is aborted to finish the
1284 * setup of the inode and release the inode. This prevents recursive
1285 * transactions and deadlocks from xfs_inactive.
1286 */
1287 if (ip) {
1288 xfs_finish_inode_setup(ip);
1289 IRELE(ip);
1290 }
1291
1292 xfs_qm_dqrele(udqp);
1293 xfs_qm_dqrele(gdqp);
1294 xfs_qm_dqrele(pdqp);
1295
1296 if (unlock_dp_on_error)
1297 xfs_iunlock(dp, XFS_ILOCK_EXCL);
1298 return error;
1299}
1300
1301int
1302xfs_create_tmpfile(
1303 struct xfs_inode *dp,
1304 umode_t mode,
1305 struct xfs_inode **ipp)
1306{
1307 struct xfs_mount *mp = dp->i_mount;
1308 struct xfs_inode *ip = NULL;
1309 struct xfs_trans *tp = NULL;
1310 int error;
1311 prid_t prid;
1312 struct xfs_dquot *udqp = NULL;
1313 struct xfs_dquot *gdqp = NULL;
1314 struct xfs_dquot *pdqp = NULL;
1315 struct xfs_trans_res *tres;
1316 uint resblks;
1317
1318 if (XFS_FORCED_SHUTDOWN(mp))
1319 return -EIO;
1320
1321 prid = xfs_get_initial_prid(dp);
1322
1323 /*
1324 * Make sure that we have allocated dquot(s) on disk.
1325 */
1326 error = xfs_qm_vop_dqalloc(dp, xfs_kuid_to_uid(current_fsuid()),
1327 xfs_kgid_to_gid(current_fsgid()), prid,
1328 XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
1329 &udqp, &gdqp, &pdqp);
1330 if (error)
1331 return error;
1332
1333 resblks = XFS_IALLOC_SPACE_RES(mp);
1334 tres = &M_RES(mp)->tr_create_tmpfile;
1335
1336 error = xfs_trans_alloc(mp, tres, resblks, 0, 0, &tp);
1337 if (error)
1338 goto out_release_inode;
1339
1340 error = xfs_trans_reserve_quota(tp, mp, udqp, gdqp,
1341 pdqp, resblks, 1, 0);
1342 if (error)
1343 goto out_trans_cancel;
1344
1345 error = xfs_dir_ialloc(&tp, dp, mode, 1, 0, prid, &ip);
1346 if (error)
1347 goto out_trans_cancel;
1348
1349 if (mp->m_flags & XFS_MOUNT_WSYNC)
1350 xfs_trans_set_sync(tp);
1351
1352 /*
1353 * Attach the dquot(s) to the inodes and modify them incore.
1354 * These ids of the inode couldn't have changed since the new
1355 * inode has been locked ever since it was created.
1356 */
1357 xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp, pdqp);
1358
1359 error = xfs_iunlink(tp, ip);
1360 if (error)
1361 goto out_trans_cancel;
1362
1363 error = xfs_trans_commit(tp);
1364 if (error)
1365 goto out_release_inode;
1366
1367 xfs_qm_dqrele(udqp);
1368 xfs_qm_dqrele(gdqp);
1369 xfs_qm_dqrele(pdqp);
1370
1371 *ipp = ip;
1372 return 0;
1373
1374 out_trans_cancel:
1375 xfs_trans_cancel(tp);
1376 out_release_inode:
1377 /*
1378 * Wait until after the current transaction is aborted to finish the
1379 * setup of the inode and release the inode. This prevents recursive
1380 * transactions and deadlocks from xfs_inactive.
1381 */
1382 if (ip) {
1383 xfs_finish_inode_setup(ip);
1384 IRELE(ip);
1385 }
1386
1387 xfs_qm_dqrele(udqp);
1388 xfs_qm_dqrele(gdqp);
1389 xfs_qm_dqrele(pdqp);
1390
1391 return error;
1392}
1393
1394int
1395xfs_link(
1396 xfs_inode_t *tdp,
1397 xfs_inode_t *sip,
1398 struct xfs_name *target_name)
1399{
1400 xfs_mount_t *mp = tdp->i_mount;
1401 xfs_trans_t *tp;
1402 int error;
1403 struct xfs_defer_ops dfops;
1404 xfs_fsblock_t first_block;
1405 int resblks;
1406
1407 trace_xfs_link(tdp, target_name);
1408
1409 ASSERT(!S_ISDIR(VFS_I(sip)->i_mode));
1410
1411 if (XFS_FORCED_SHUTDOWN(mp))
1412 return -EIO;
1413
1414 error = xfs_qm_dqattach(sip, 0);
1415 if (error)
1416 goto std_return;
1417
1418 error = xfs_qm_dqattach(tdp, 0);
1419 if (error)
1420 goto std_return;
1421
1422 resblks = XFS_LINK_SPACE_RES(mp, target_name->len);
1423 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_link, resblks, 0, 0, &tp);
1424 if (error == -ENOSPC) {
1425 resblks = 0;
1426 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_link, 0, 0, 0, &tp);
1427 }
1428 if (error)
1429 goto std_return;
1430
1431 xfs_lock_two_inodes(sip, XFS_ILOCK_EXCL, tdp, XFS_ILOCK_EXCL);
1432
1433 xfs_trans_ijoin(tp, sip, XFS_ILOCK_EXCL);
1434 xfs_trans_ijoin(tp, tdp, XFS_ILOCK_EXCL);
1435
1436 /*
1437 * If we are using project inheritance, we only allow hard link
1438 * creation in our tree when the project IDs are the same; else
1439 * the tree quota mechanism could be circumvented.
1440 */
1441 if (unlikely((tdp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) &&
1442 (xfs_get_projid(tdp) != xfs_get_projid(sip)))) {
1443 error = -EXDEV;
1444 goto error_return;
1445 }
1446
1447 if (!resblks) {
1448 error = xfs_dir_canenter(tp, tdp, target_name);
1449 if (error)
1450 goto error_return;
1451 }
1452
1453 xfs_defer_init(&dfops, &first_block);
1454
1455 /*
1456 * Handle initial link state of O_TMPFILE inode
1457 */
1458 if (VFS_I(sip)->i_nlink == 0) {
1459 error = xfs_iunlink_remove(tp, sip);
1460 if (error)
1461 goto error_return;
1462 }
1463
1464 error = xfs_dir_createname(tp, tdp, target_name, sip->i_ino,
1465 &first_block, &dfops, resblks);
1466 if (error)
1467 goto error_return;
1468 xfs_trans_ichgtime(tp, tdp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1469 xfs_trans_log_inode(tp, tdp, XFS_ILOG_CORE);
1470
1471 error = xfs_bumplink(tp, sip);
1472 if (error)
1473 goto error_return;
1474
1475 /*
1476 * If this is a synchronous mount, make sure that the
1477 * link transaction goes to disk before returning to
1478 * the user.
1479 */
1480 if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
1481 xfs_trans_set_sync(tp);
1482
1483 error = xfs_defer_finish(&tp, &dfops);
1484 if (error) {
1485 xfs_defer_cancel(&dfops);
1486 goto error_return;
1487 }
1488
1489 return xfs_trans_commit(tp);
1490
1491 error_return:
1492 xfs_trans_cancel(tp);
1493 std_return:
1494 return error;
1495}
1496
1497/* Clear the reflink flag and the cowblocks tag if possible. */
1498static void
1499xfs_itruncate_clear_reflink_flags(
1500 struct xfs_inode *ip)
1501{
1502 struct xfs_ifork *dfork;
1503 struct xfs_ifork *cfork;
1504
1505 if (!xfs_is_reflink_inode(ip))
1506 return;
1507 dfork = XFS_IFORK_PTR(ip, XFS_DATA_FORK);
1508 cfork = XFS_IFORK_PTR(ip, XFS_COW_FORK);
1509 if (dfork->if_bytes == 0 && cfork->if_bytes == 0)
1510 ip->i_d.di_flags2 &= ~XFS_DIFLAG2_REFLINK;
1511 if (cfork->if_bytes == 0)
1512 xfs_inode_clear_cowblocks_tag(ip);
1513}
1514
1515/*
1516 * Free up the underlying blocks past new_size. The new size must be smaller
1517 * than the current size. This routine can be used both for the attribute and
1518 * data fork, and does not modify the inode size, which is left to the caller.
1519 *
1520 * The transaction passed to this routine must have made a permanent log
1521 * reservation of at least XFS_ITRUNCATE_LOG_RES. This routine may commit the
1522 * given transaction and start new ones, so make sure everything involved in
1523 * the transaction is tidy before calling here. Some transaction will be
1524 * returned to the caller to be committed. The incoming transaction must
1525 * already include the inode, and both inode locks must be held exclusively.
1526 * The inode must also be "held" within the transaction. On return the inode
1527 * will be "held" within the returned transaction. This routine does NOT
1528 * require any disk space to be reserved for it within the transaction.
1529 *
1530 * If we get an error, we must return with the inode locked and linked into the
1531 * current transaction. This keeps things simple for the higher level code,
1532 * because it always knows that the inode is locked and held in the transaction
1533 * that returns to it whether errors occur or not. We don't mark the inode
1534 * dirty on error so that transactions can be easily aborted if possible.
1535 */
1536int
1537xfs_itruncate_extents(
1538 struct xfs_trans **tpp,
1539 struct xfs_inode *ip,
1540 int whichfork,
1541 xfs_fsize_t new_size)
1542{
1543 struct xfs_mount *mp = ip->i_mount;
1544 struct xfs_trans *tp = *tpp;
1545 struct xfs_defer_ops dfops;
1546 xfs_fsblock_t first_block;
1547 xfs_fileoff_t first_unmap_block;
1548 xfs_fileoff_t last_block;
1549 xfs_filblks_t unmap_len;
1550 int error = 0;
1551 int done = 0;
1552
1553 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
1554 ASSERT(!atomic_read(&VFS_I(ip)->i_count) ||
1555 xfs_isilocked(ip, XFS_IOLOCK_EXCL));
1556 ASSERT(new_size <= XFS_ISIZE(ip));
1557 ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
1558 ASSERT(ip->i_itemp != NULL);
1559 ASSERT(ip->i_itemp->ili_lock_flags == 0);
1560 ASSERT(!XFS_NOT_DQATTACHED(mp, ip));
1561
1562 trace_xfs_itruncate_extents_start(ip, new_size);
1563
1564 /*
1565 * Since it is possible for space to become allocated beyond
1566 * the end of the file (in a crash where the space is allocated
1567 * but the inode size is not yet updated), simply remove any
1568 * blocks which show up between the new EOF and the maximum
1569 * possible file size. If the first block to be removed is
1570 * beyond the maximum file size (ie it is the same as last_block),
1571 * then there is nothing to do.
1572 */
1573 first_unmap_block = XFS_B_TO_FSB(mp, (xfs_ufsize_t)new_size);
1574 last_block = XFS_B_TO_FSB(mp, mp->m_super->s_maxbytes);
1575 if (first_unmap_block == last_block)
1576 return 0;
1577
1578 ASSERT(first_unmap_block < last_block);
1579 unmap_len = last_block - first_unmap_block + 1;
1580 while (!done) {
1581 xfs_defer_init(&dfops, &first_block);
1582 error = xfs_bunmapi(tp, ip,
1583 first_unmap_block, unmap_len,
1584 xfs_bmapi_aflag(whichfork),
1585 XFS_ITRUNC_MAX_EXTENTS,
1586 &first_block, &dfops,
1587 &done);
1588 if (error)
1589 goto out_bmap_cancel;
1590
1591 /*
1592 * Duplicate the transaction that has the permanent
1593 * reservation and commit the old transaction.
1594 */
1595 xfs_defer_ijoin(&dfops, ip);
1596 error = xfs_defer_finish(&tp, &dfops);
1597 if (error)
1598 goto out_bmap_cancel;
1599
1600 error = xfs_trans_roll_inode(&tp, ip);
1601 if (error)
1602 goto out;
1603 }
1604
1605 if (whichfork == XFS_DATA_FORK) {
1606 /* Remove all pending CoW reservations. */
1607 error = xfs_reflink_cancel_cow_blocks(ip, &tp,
1608 first_unmap_block, last_block, true);
1609 if (error)
1610 goto out;
1611
1612 xfs_itruncate_clear_reflink_flags(ip);
1613 }
1614
1615 /*
1616 * Always re-log the inode so that our permanent transaction can keep
1617 * on rolling it forward in the log.
1618 */
1619 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1620
1621 trace_xfs_itruncate_extents_end(ip, new_size);
1622
1623out:
1624 *tpp = tp;
1625 return error;
1626out_bmap_cancel:
1627 /*
1628 * If the bunmapi call encounters an error, return to the caller where
1629 * the transaction can be properly aborted. We just need to make sure
1630 * we're not holding any resources that we were not when we came in.
1631 */
1632 xfs_defer_cancel(&dfops);
1633 goto out;
1634}
1635
1636int
1637xfs_release(
1638 xfs_inode_t *ip)
1639{
1640 xfs_mount_t *mp = ip->i_mount;
1641 int error;
1642
1643 if (!S_ISREG(VFS_I(ip)->i_mode) || (VFS_I(ip)->i_mode == 0))
1644 return 0;
1645
1646 /* If this is a read-only mount, don't do this (would generate I/O) */
1647 if (mp->m_flags & XFS_MOUNT_RDONLY)
1648 return 0;
1649
1650 if (!XFS_FORCED_SHUTDOWN(mp)) {
1651 int truncated;
1652
1653 /*
1654 * If we previously truncated this file and removed old data
1655 * in the process, we want to initiate "early" writeout on
1656 * the last close. This is an attempt to combat the notorious
1657 * NULL files problem which is particularly noticeable from a
1658 * truncate down, buffered (re-)write (delalloc), followed by
1659 * a crash. What we are effectively doing here is
1660 * significantly reducing the time window where we'd otherwise
1661 * be exposed to that problem.
1662 */
1663 truncated = xfs_iflags_test_and_clear(ip, XFS_ITRUNCATED);
1664 if (truncated) {
1665 xfs_iflags_clear(ip, XFS_IDIRTY_RELEASE);
1666 if (ip->i_delayed_blks > 0) {
1667 error = filemap_flush(VFS_I(ip)->i_mapping);
1668 if (error)
1669 return error;
1670 }
1671 }
1672 }
1673
1674 if (VFS_I(ip)->i_nlink == 0)
1675 return 0;
1676
1677 if (xfs_can_free_eofblocks(ip, false)) {
1678
1679 /*
1680 * Check if the inode is being opened, written and closed
1681 * frequently and we have delayed allocation blocks outstanding
1682 * (e.g. streaming writes from the NFS server), truncating the
1683 * blocks past EOF will cause fragmentation to occur.
1684 *
1685 * In this case don't do the truncation, but we have to be
1686 * careful how we detect this case. Blocks beyond EOF show up as
1687 * i_delayed_blks even when the inode is clean, so we need to
1688 * truncate them away first before checking for a dirty release.
1689 * Hence on the first dirty close we will still remove the
1690 * speculative allocation, but after that we will leave it in
1691 * place.
1692 */
1693 if (xfs_iflags_test(ip, XFS_IDIRTY_RELEASE))
1694 return 0;
1695 /*
1696 * If we can't get the iolock just skip truncating the blocks
1697 * past EOF because we could deadlock with the mmap_sem
1698 * otherwise. We'll get another chance to drop them once the
1699 * last reference to the inode is dropped, so we'll never leak
1700 * blocks permanently.
1701 */
1702 if (xfs_ilock_nowait(ip, XFS_IOLOCK_EXCL)) {
1703 error = xfs_free_eofblocks(ip);
1704 xfs_iunlock(ip, XFS_IOLOCK_EXCL);
1705 if (error)
1706 return error;
1707 }
1708
1709 /* delalloc blocks after truncation means it really is dirty */
1710 if (ip->i_delayed_blks)
1711 xfs_iflags_set(ip, XFS_IDIRTY_RELEASE);
1712 }
1713 return 0;
1714}
1715
1716/*
1717 * xfs_inactive_truncate
1718 *
1719 * Called to perform a truncate when an inode becomes unlinked.
1720 */
1721STATIC int
1722xfs_inactive_truncate(
1723 struct xfs_inode *ip)
1724{
1725 struct xfs_mount *mp = ip->i_mount;
1726 struct xfs_trans *tp;
1727 int error;
1728
1729 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, 0, 0, 0, &tp);
1730 if (error) {
1731 ASSERT(XFS_FORCED_SHUTDOWN(mp));
1732 return error;
1733 }
1734
1735 xfs_ilock(ip, XFS_ILOCK_EXCL);
1736 xfs_trans_ijoin(tp, ip, 0);
1737
1738 /*
1739 * Log the inode size first to prevent stale data exposure in the event
1740 * of a system crash before the truncate completes. See the related
1741 * comment in xfs_vn_setattr_size() for details.
1742 */
1743 ip->i_d.di_size = 0;
1744 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1745
1746 error = xfs_itruncate_extents(&tp, ip, XFS_DATA_FORK, 0);
1747 if (error)
1748 goto error_trans_cancel;
1749
1750 ASSERT(ip->i_d.di_nextents == 0);
1751
1752 error = xfs_trans_commit(tp);
1753 if (error)
1754 goto error_unlock;
1755
1756 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1757 return 0;
1758
1759error_trans_cancel:
1760 xfs_trans_cancel(tp);
1761error_unlock:
1762 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1763 return error;
1764}
1765
1766/*
1767 * xfs_inactive_ifree()
1768 *
1769 * Perform the inode free when an inode is unlinked.
1770 */
1771STATIC int
1772xfs_inactive_ifree(
1773 struct xfs_inode *ip)
1774{
1775 struct xfs_defer_ops dfops;
1776 xfs_fsblock_t first_block;
1777 struct xfs_mount *mp = ip->i_mount;
1778 struct xfs_trans *tp;
1779 int error;
1780
1781 /*
1782 * We try to use a per-AG reservation for any block needed by the finobt
1783 * tree, but as the finobt feature predates the per-AG reservation
1784 * support a degraded file system might not have enough space for the
1785 * reservation at mount time. In that case try to dip into the reserved
1786 * pool and pray.
1787 *
1788 * Send a warning if the reservation does happen to fail, as the inode
1789 * now remains allocated and sits on the unlinked list until the fs is
1790 * repaired.
1791 */
1792 if (unlikely(mp->m_inotbt_nores)) {
1793 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ifree,
1794 XFS_IFREE_SPACE_RES(mp), 0, XFS_TRANS_RESERVE,
1795 &tp);
1796 } else {
1797 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ifree, 0, 0, 0, &tp);
1798 }
1799 if (error) {
1800 if (error == -ENOSPC) {
1801 xfs_warn_ratelimited(mp,
1802 "Failed to remove inode(s) from unlinked list. "
1803 "Please free space, unmount and run xfs_repair.");
1804 } else {
1805 ASSERT(XFS_FORCED_SHUTDOWN(mp));
1806 }
1807 return error;
1808 }
1809
1810 xfs_ilock(ip, XFS_ILOCK_EXCL);
1811 xfs_trans_ijoin(tp, ip, 0);
1812
1813 xfs_defer_init(&dfops, &first_block);
1814 error = xfs_ifree(tp, ip, &dfops);
1815 if (error) {
1816 /*
1817 * If we fail to free the inode, shut down. The cancel
1818 * might do that, we need to make sure. Otherwise the
1819 * inode might be lost for a long time or forever.
1820 */
1821 if (!XFS_FORCED_SHUTDOWN(mp)) {
1822 xfs_notice(mp, "%s: xfs_ifree returned error %d",
1823 __func__, error);
1824 xfs_force_shutdown(mp, SHUTDOWN_META_IO_ERROR);
1825 }
1826 xfs_trans_cancel(tp);
1827 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1828 return error;
1829 }
1830
1831 /*
1832 * Credit the quota account(s). The inode is gone.
1833 */
1834 xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_ICOUNT, -1);
1835
1836 /*
1837 * Just ignore errors at this point. There is nothing we can do except
1838 * to try to keep going. Make sure it's not a silent error.
1839 */
1840 error = xfs_defer_finish(&tp, &dfops);
1841 if (error) {
1842 xfs_notice(mp, "%s: xfs_defer_finish returned error %d",
1843 __func__, error);
1844 xfs_defer_cancel(&dfops);
1845 }
1846 error = xfs_trans_commit(tp);
1847 if (error)
1848 xfs_notice(mp, "%s: xfs_trans_commit returned error %d",
1849 __func__, error);
1850
1851 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1852 return 0;
1853}
1854
1855/*
1856 * xfs_inactive
1857 *
1858 * This is called when the vnode reference count for the vnode
1859 * goes to zero. If the file has been unlinked, then it must
1860 * now be truncated. Also, we clear all of the read-ahead state
1861 * kept for the inode here since the file is now closed.
1862 */
1863void
1864xfs_inactive(
1865 xfs_inode_t *ip)
1866{
1867 struct xfs_mount *mp;
1868 struct xfs_ifork *cow_ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK);
1869 int error;
1870 int truncate = 0;
1871
1872 /*
1873 * If the inode is already free, then there can be nothing
1874 * to clean up here.
1875 */
1876 if (VFS_I(ip)->i_mode == 0) {
1877 ASSERT(ip->i_df.if_real_bytes == 0);
1878 ASSERT(ip->i_df.if_broot_bytes == 0);
1879 return;
1880 }
1881
1882 mp = ip->i_mount;
1883 ASSERT(!xfs_iflags_test(ip, XFS_IRECOVERY));
1884
1885 /* If this is a read-only mount, don't do this (would generate I/O) */
1886 if (mp->m_flags & XFS_MOUNT_RDONLY)
1887 return;
1888
1889 /* Try to clean out the cow blocks if there are any. */
1890 if (xfs_is_reflink_inode(ip) && cow_ifp->if_bytes > 0)
1891 xfs_reflink_cancel_cow_range(ip, 0, NULLFILEOFF, true);
1892
1893 if (VFS_I(ip)->i_nlink != 0) {
1894 /*
1895 * force is true because we are evicting an inode from the
1896 * cache. Post-eof blocks must be freed, lest we end up with
1897 * broken free space accounting.
1898 *
1899 * Note: don't bother with iolock here since lockdep complains
1900 * about acquiring it in reclaim context. We have the only
1901 * reference to the inode at this point anyways.
1902 */
1903 if (xfs_can_free_eofblocks(ip, true))
1904 xfs_free_eofblocks(ip);
1905
1906 return;
1907 }
1908
1909 if (S_ISREG(VFS_I(ip)->i_mode) &&
1910 (ip->i_d.di_size != 0 || XFS_ISIZE(ip) != 0 ||
1911 ip->i_d.di_nextents > 0 || ip->i_delayed_blks > 0))
1912 truncate = 1;
1913
1914 error = xfs_qm_dqattach(ip, 0);
1915 if (error)
1916 return;
1917
1918 if (S_ISLNK(VFS_I(ip)->i_mode))
1919 error = xfs_inactive_symlink(ip);
1920 else if (truncate)
1921 error = xfs_inactive_truncate(ip);
1922 if (error)
1923 return;
1924
1925 /*
1926 * If there are attributes associated with the file then blow them away
1927 * now. The code calls a routine that recursively deconstructs the
1928 * attribute fork. If also blows away the in-core attribute fork.
1929 */
1930 if (XFS_IFORK_Q(ip)) {
1931 error = xfs_attr_inactive(ip);
1932 if (error)
1933 return;
1934 }
1935
1936 ASSERT(!ip->i_afp);
1937 ASSERT(ip->i_d.di_anextents == 0);
1938 ASSERT(ip->i_d.di_forkoff == 0);
1939
1940 /*
1941 * Free the inode.
1942 */
1943 error = xfs_inactive_ifree(ip);
1944 if (error)
1945 return;
1946
1947 /*
1948 * Release the dquots held by inode, if any.
1949 */
1950 xfs_qm_dqdetach(ip);
1951}
1952
1953/*
1954 * This is called when the inode's link count goes to 0 or we are creating a
1955 * tmpfile via O_TMPFILE. In the case of a tmpfile, @ignore_linkcount will be
1956 * set to true as the link count is dropped to zero by the VFS after we've
1957 * created the file successfully, so we have to add it to the unlinked list
1958 * while the link count is non-zero.
1959 *
1960 * We place the on-disk inode on a list in the AGI. It will be pulled from this
1961 * list when the inode is freed.
1962 */
1963STATIC int
1964xfs_iunlink(
1965 struct xfs_trans *tp,
1966 struct xfs_inode *ip)
1967{
1968 xfs_mount_t *mp = tp->t_mountp;
1969 xfs_agi_t *agi;
1970 xfs_dinode_t *dip;
1971 xfs_buf_t *agibp;
1972 xfs_buf_t *ibp;
1973 xfs_agino_t agino;
1974 short bucket_index;
1975 int offset;
1976 int error;
1977
1978 ASSERT(VFS_I(ip)->i_mode != 0);
1979
1980 /*
1981 * Get the agi buffer first. It ensures lock ordering
1982 * on the list.
1983 */
1984 error = xfs_read_agi(mp, tp, XFS_INO_TO_AGNO(mp, ip->i_ino), &agibp);
1985 if (error)
1986 return error;
1987 agi = XFS_BUF_TO_AGI(agibp);
1988
1989 /*
1990 * Get the index into the agi hash table for the
1991 * list this inode will go on.
1992 */
1993 agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
1994 ASSERT(agino != 0);
1995 bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
1996 ASSERT(agi->agi_unlinked[bucket_index]);
1997 ASSERT(be32_to_cpu(agi->agi_unlinked[bucket_index]) != agino);
1998
1999 if (agi->agi_unlinked[bucket_index] != cpu_to_be32(NULLAGINO)) {
2000 /*
2001 * There is already another inode in the bucket we need
2002 * to add ourselves to. Add us at the front of the list.
2003 * Here we put the head pointer into our next pointer,
2004 * and then we fall through to point the head at us.
2005 */
2006 error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &ibp,
2007 0, 0);
2008 if (error)
2009 return error;
2010
2011 ASSERT(dip->di_next_unlinked == cpu_to_be32(NULLAGINO));
2012 dip->di_next_unlinked = agi->agi_unlinked[bucket_index];
2013 offset = ip->i_imap.im_boffset +
2014 offsetof(xfs_dinode_t, di_next_unlinked);
2015
2016 /* need to recalc the inode CRC if appropriate */
2017 xfs_dinode_calc_crc(mp, dip);
2018
2019 xfs_trans_inode_buf(tp, ibp);
2020 xfs_trans_log_buf(tp, ibp, offset,
2021 (offset + sizeof(xfs_agino_t) - 1));
2022 xfs_inobp_check(mp, ibp);
2023 }
2024
2025 /*
2026 * Point the bucket head pointer at the inode being inserted.
2027 */
2028 ASSERT(agino != 0);
2029 agi->agi_unlinked[bucket_index] = cpu_to_be32(agino);
2030 offset = offsetof(xfs_agi_t, agi_unlinked) +
2031 (sizeof(xfs_agino_t) * bucket_index);
2032 xfs_trans_log_buf(tp, agibp, offset,
2033 (offset + sizeof(xfs_agino_t) - 1));
2034 return 0;
2035}
2036
2037/*
2038 * Pull the on-disk inode from the AGI unlinked list.
2039 */
2040STATIC int
2041xfs_iunlink_remove(
2042 xfs_trans_t *tp,
2043 xfs_inode_t *ip)
2044{
2045 xfs_ino_t next_ino;
2046 xfs_mount_t *mp;
2047 xfs_agi_t *agi;
2048 xfs_dinode_t *dip;
2049 xfs_buf_t *agibp;
2050 xfs_buf_t *ibp;
2051 xfs_agnumber_t agno;
2052 xfs_agino_t agino;
2053 xfs_agino_t next_agino;
2054 xfs_buf_t *last_ibp;
2055 xfs_dinode_t *last_dip = NULL;
2056 short bucket_index;
2057 int offset, last_offset = 0;
2058 int error;
2059
2060 mp = tp->t_mountp;
2061 agno = XFS_INO_TO_AGNO(mp, ip->i_ino);
2062
2063 /*
2064 * Get the agi buffer first. It ensures lock ordering
2065 * on the list.
2066 */
2067 error = xfs_read_agi(mp, tp, agno, &agibp);
2068 if (error)
2069 return error;
2070
2071 agi = XFS_BUF_TO_AGI(agibp);
2072
2073 /*
2074 * Get the index into the agi hash table for the
2075 * list this inode will go on.
2076 */
2077 agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
2078 ASSERT(agino != 0);
2079 bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
2080 ASSERT(agi->agi_unlinked[bucket_index] != cpu_to_be32(NULLAGINO));
2081 ASSERT(agi->agi_unlinked[bucket_index]);
2082
2083 if (be32_to_cpu(agi->agi_unlinked[bucket_index]) == agino) {
2084 /*
2085 * We're at the head of the list. Get the inode's on-disk
2086 * buffer to see if there is anyone after us on the list.
2087 * Only modify our next pointer if it is not already NULLAGINO.
2088 * This saves us the overhead of dealing with the buffer when
2089 * there is no need to change it.
2090 */
2091 error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &ibp,
2092 0, 0);
2093 if (error) {
2094 xfs_warn(mp, "%s: xfs_imap_to_bp returned error %d.",
2095 __func__, error);
2096 return error;
2097 }
2098 next_agino = be32_to_cpu(dip->di_next_unlinked);
2099 ASSERT(next_agino != 0);
2100 if (next_agino != NULLAGINO) {
2101 dip->di_next_unlinked = cpu_to_be32(NULLAGINO);
2102 offset = ip->i_imap.im_boffset +
2103 offsetof(xfs_dinode_t, di_next_unlinked);
2104
2105 /* need to recalc the inode CRC if appropriate */
2106 xfs_dinode_calc_crc(mp, dip);
2107
2108 xfs_trans_inode_buf(tp, ibp);
2109 xfs_trans_log_buf(tp, ibp, offset,
2110 (offset + sizeof(xfs_agino_t) - 1));
2111 xfs_inobp_check(mp, ibp);
2112 } else {
2113 xfs_trans_brelse(tp, ibp);
2114 }
2115 /*
2116 * Point the bucket head pointer at the next inode.
2117 */
2118 ASSERT(next_agino != 0);
2119 ASSERT(next_agino != agino);
2120 agi->agi_unlinked[bucket_index] = cpu_to_be32(next_agino);
2121 offset = offsetof(xfs_agi_t, agi_unlinked) +
2122 (sizeof(xfs_agino_t) * bucket_index);
2123 xfs_trans_log_buf(tp, agibp, offset,
2124 (offset + sizeof(xfs_agino_t) - 1));
2125 } else {
2126 /*
2127 * We need to search the list for the inode being freed.
2128 */
2129 next_agino = be32_to_cpu(agi->agi_unlinked[bucket_index]);
2130 last_ibp = NULL;
2131 while (next_agino != agino) {
2132 struct xfs_imap imap;
2133
2134 if (last_ibp)
2135 xfs_trans_brelse(tp, last_ibp);
2136
2137 imap.im_blkno = 0;
2138 next_ino = XFS_AGINO_TO_INO(mp, agno, next_agino);
2139
2140 error = xfs_imap(mp, tp, next_ino, &imap, 0);
2141 if (error) {
2142 xfs_warn(mp,
2143 "%s: xfs_imap returned error %d.",
2144 __func__, error);
2145 return error;
2146 }
2147
2148 error = xfs_imap_to_bp(mp, tp, &imap, &last_dip,
2149 &last_ibp, 0, 0);
2150 if (error) {
2151 xfs_warn(mp,
2152 "%s: xfs_imap_to_bp returned error %d.",
2153 __func__, error);
2154 return error;
2155 }
2156
2157 last_offset = imap.im_boffset;
2158 next_agino = be32_to_cpu(last_dip->di_next_unlinked);
2159 ASSERT(next_agino != NULLAGINO);
2160 ASSERT(next_agino != 0);
2161 }
2162
2163 /*
2164 * Now last_ibp points to the buffer previous to us on the
2165 * unlinked list. Pull us from the list.
2166 */
2167 error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &ibp,
2168 0, 0);
2169 if (error) {
2170 xfs_warn(mp, "%s: xfs_imap_to_bp(2) returned error %d.",
2171 __func__, error);
2172 return error;
2173 }
2174 next_agino = be32_to_cpu(dip->di_next_unlinked);
2175 ASSERT(next_agino != 0);
2176 ASSERT(next_agino != agino);
2177 if (next_agino != NULLAGINO) {
2178 dip->di_next_unlinked = cpu_to_be32(NULLAGINO);
2179 offset = ip->i_imap.im_boffset +
2180 offsetof(xfs_dinode_t, di_next_unlinked);
2181
2182 /* need to recalc the inode CRC if appropriate */
2183 xfs_dinode_calc_crc(mp, dip);
2184
2185 xfs_trans_inode_buf(tp, ibp);
2186 xfs_trans_log_buf(tp, ibp, offset,
2187 (offset + sizeof(xfs_agino_t) - 1));
2188 xfs_inobp_check(mp, ibp);
2189 } else {
2190 xfs_trans_brelse(tp, ibp);
2191 }
2192 /*
2193 * Point the previous inode on the list to the next inode.
2194 */
2195 last_dip->di_next_unlinked = cpu_to_be32(next_agino);
2196 ASSERT(next_agino != 0);
2197 offset = last_offset + offsetof(xfs_dinode_t, di_next_unlinked);
2198
2199 /* need to recalc the inode CRC if appropriate */
2200 xfs_dinode_calc_crc(mp, last_dip);
2201
2202 xfs_trans_inode_buf(tp, last_ibp);
2203 xfs_trans_log_buf(tp, last_ibp, offset,
2204 (offset + sizeof(xfs_agino_t) - 1));
2205 xfs_inobp_check(mp, last_ibp);
2206 }
2207 return 0;
2208}
2209
2210/*
2211 * A big issue when freeing the inode cluster is that we _cannot_ skip any
2212 * inodes that are in memory - they all must be marked stale and attached to
2213 * the cluster buffer.
2214 */
2215STATIC int
2216xfs_ifree_cluster(
2217 xfs_inode_t *free_ip,
2218 xfs_trans_t *tp,
2219 struct xfs_icluster *xic)
2220{
2221 xfs_mount_t *mp = free_ip->i_mount;
2222 int blks_per_cluster;
2223 int inodes_per_cluster;
2224 int nbufs;
2225 int i, j;
2226 int ioffset;
2227 xfs_daddr_t blkno;
2228 xfs_buf_t *bp;
2229 xfs_inode_t *ip;
2230 xfs_inode_log_item_t *iip;
2231 struct xfs_log_item *lip;
2232 struct xfs_perag *pag;
2233 xfs_ino_t inum;
2234
2235 inum = xic->first_ino;
2236 pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, inum));
2237 blks_per_cluster = xfs_icluster_size_fsb(mp);
2238 inodes_per_cluster = blks_per_cluster << mp->m_sb.sb_inopblog;
2239 nbufs = mp->m_ialloc_blks / blks_per_cluster;
2240
2241 for (j = 0; j < nbufs; j++, inum += inodes_per_cluster) {
2242 /*
2243 * The allocation bitmap tells us which inodes of the chunk were
2244 * physically allocated. Skip the cluster if an inode falls into
2245 * a sparse region.
2246 */
2247 ioffset = inum - xic->first_ino;
2248 if ((xic->alloc & XFS_INOBT_MASK(ioffset)) == 0) {
2249 ASSERT(do_mod(ioffset, inodes_per_cluster) == 0);
2250 continue;
2251 }
2252
2253 blkno = XFS_AGB_TO_DADDR(mp, XFS_INO_TO_AGNO(mp, inum),
2254 XFS_INO_TO_AGBNO(mp, inum));
2255
2256 /*
2257 * We obtain and lock the backing buffer first in the process
2258 * here, as we have to ensure that any dirty inode that we
2259 * can't get the flush lock on is attached to the buffer.
2260 * If we scan the in-memory inodes first, then buffer IO can
2261 * complete before we get a lock on it, and hence we may fail
2262 * to mark all the active inodes on the buffer stale.
2263 */
2264 bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, blkno,
2265 mp->m_bsize * blks_per_cluster,
2266 XBF_UNMAPPED);
2267
2268 if (!bp)
2269 return -ENOMEM;
2270
2271 /*
2272 * This buffer may not have been correctly initialised as we
2273 * didn't read it from disk. That's not important because we are
2274 * only using to mark the buffer as stale in the log, and to
2275 * attach stale cached inodes on it. That means it will never be
2276 * dispatched for IO. If it is, we want to know about it, and we
2277 * want it to fail. We can acheive this by adding a write
2278 * verifier to the buffer.
2279 */
2280 bp->b_ops = &xfs_inode_buf_ops;
2281
2282 /*
2283 * Walk the inodes already attached to the buffer and mark them
2284 * stale. These will all have the flush locks held, so an
2285 * in-memory inode walk can't lock them. By marking them all
2286 * stale first, we will not attempt to lock them in the loop
2287 * below as the XFS_ISTALE flag will be set.
2288 */
2289 list_for_each_entry(lip, &bp->b_li_list, li_bio_list) {
2290 if (lip->li_type == XFS_LI_INODE) {
2291 iip = (xfs_inode_log_item_t *)lip;
2292 ASSERT(iip->ili_logged == 1);
2293 lip->li_cb = xfs_istale_done;
2294 xfs_trans_ail_copy_lsn(mp->m_ail,
2295 &iip->ili_flush_lsn,
2296 &iip->ili_item.li_lsn);
2297 xfs_iflags_set(iip->ili_inode, XFS_ISTALE);
2298 }
2299 }
2300
2301
2302 /*
2303 * For each inode in memory attempt to add it to the inode
2304 * buffer and set it up for being staled on buffer IO
2305 * completion. This is safe as we've locked out tail pushing
2306 * and flushing by locking the buffer.
2307 *
2308 * We have already marked every inode that was part of a
2309 * transaction stale above, which means there is no point in
2310 * even trying to lock them.
2311 */
2312 for (i = 0; i < inodes_per_cluster; i++) {
2313retry:
2314 rcu_read_lock();
2315 ip = radix_tree_lookup(&pag->pag_ici_root,
2316 XFS_INO_TO_AGINO(mp, (inum + i)));
2317
2318 /* Inode not in memory, nothing to do */
2319 if (!ip) {
2320 rcu_read_unlock();
2321 continue;
2322 }
2323
2324 /*
2325 * because this is an RCU protected lookup, we could
2326 * find a recently freed or even reallocated inode
2327 * during the lookup. We need to check under the
2328 * i_flags_lock for a valid inode here. Skip it if it
2329 * is not valid, the wrong inode or stale.
2330 */
2331 spin_lock(&ip->i_flags_lock);
2332 if (ip->i_ino != inum + i ||
2333 __xfs_iflags_test(ip, XFS_ISTALE)) {
2334 spin_unlock(&ip->i_flags_lock);
2335 rcu_read_unlock();
2336 continue;
2337 }
2338 spin_unlock(&ip->i_flags_lock);
2339
2340 /*
2341 * Don't try to lock/unlock the current inode, but we
2342 * _cannot_ skip the other inodes that we did not find
2343 * in the list attached to the buffer and are not
2344 * already marked stale. If we can't lock it, back off
2345 * and retry.
2346 */
2347 if (ip != free_ip) {
2348 if (!xfs_ilock_nowait(ip, XFS_ILOCK_EXCL)) {
2349 rcu_read_unlock();
2350 delay(1);
2351 goto retry;
2352 }
2353
2354 /*
2355 * Check the inode number again in case we're
2356 * racing with freeing in xfs_reclaim_inode().
2357 * See the comments in that function for more
2358 * information as to why the initial check is
2359 * not sufficient.
2360 */
2361 if (ip->i_ino != inum + i) {
2362 xfs_iunlock(ip, XFS_ILOCK_EXCL);
2363 rcu_read_unlock();
2364 continue;
2365 }
2366 }
2367 rcu_read_unlock();
2368
2369 xfs_iflock(ip);
2370 xfs_iflags_set(ip, XFS_ISTALE);
2371
2372 /*
2373 * we don't need to attach clean inodes or those only
2374 * with unlogged changes (which we throw away, anyway).
2375 */
2376 iip = ip->i_itemp;
2377 if (!iip || xfs_inode_clean(ip)) {
2378 ASSERT(ip != free_ip);
2379 xfs_ifunlock(ip);
2380 xfs_iunlock(ip, XFS_ILOCK_EXCL);
2381 continue;
2382 }
2383
2384 iip->ili_last_fields = iip->ili_fields;
2385 iip->ili_fields = 0;
2386 iip->ili_fsync_fields = 0;
2387 iip->ili_logged = 1;
2388 xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn,
2389 &iip->ili_item.li_lsn);
2390
2391 xfs_buf_attach_iodone(bp, xfs_istale_done,
2392 &iip->ili_item);
2393
2394 if (ip != free_ip)
2395 xfs_iunlock(ip, XFS_ILOCK_EXCL);
2396 }
2397
2398 xfs_trans_stale_inode_buf(tp, bp);
2399 xfs_trans_binval(tp, bp);
2400 }
2401
2402 xfs_perag_put(pag);
2403 return 0;
2404}
2405
2406/*
2407 * Free any local-format buffers sitting around before we reset to
2408 * extents format.
2409 */
2410static inline void
2411xfs_ifree_local_data(
2412 struct xfs_inode *ip,
2413 int whichfork)
2414{
2415 struct xfs_ifork *ifp;
2416
2417 if (XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_LOCAL)
2418 return;
2419
2420 ifp = XFS_IFORK_PTR(ip, whichfork);
2421 xfs_idata_realloc(ip, -ifp->if_bytes, whichfork);
2422}
2423
2424/*
2425 * This is called to return an inode to the inode free list.
2426 * The inode should already be truncated to 0 length and have
2427 * no pages associated with it. This routine also assumes that
2428 * the inode is already a part of the transaction.
2429 *
2430 * The on-disk copy of the inode will have been added to the list
2431 * of unlinked inodes in the AGI. We need to remove the inode from
2432 * that list atomically with respect to freeing it here.
2433 */
2434int
2435xfs_ifree(
2436 xfs_trans_t *tp,
2437 xfs_inode_t *ip,
2438 struct xfs_defer_ops *dfops)
2439{
2440 int error;
2441 struct xfs_icluster xic = { 0 };
2442
2443 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
2444 ASSERT(VFS_I(ip)->i_nlink == 0);
2445 ASSERT(ip->i_d.di_nextents == 0);
2446 ASSERT(ip->i_d.di_anextents == 0);
2447 ASSERT(ip->i_d.di_size == 0 || !S_ISREG(VFS_I(ip)->i_mode));
2448 ASSERT(ip->i_d.di_nblocks == 0);
2449
2450 /*
2451 * Pull the on-disk inode from the AGI unlinked list.
2452 */
2453 error = xfs_iunlink_remove(tp, ip);
2454 if (error)
2455 return error;
2456
2457 error = xfs_difree(tp, ip->i_ino, dfops, &xic);
2458 if (error)
2459 return error;
2460
2461 xfs_ifree_local_data(ip, XFS_DATA_FORK);
2462 xfs_ifree_local_data(ip, XFS_ATTR_FORK);
2463
2464 VFS_I(ip)->i_mode = 0; /* mark incore inode as free */
2465 ip->i_d.di_flags = 0;
2466 ip->i_d.di_flags2 = 0;
2467 ip->i_d.di_dmevmask = 0;
2468 ip->i_d.di_forkoff = 0; /* mark the attr fork not in use */
2469 ip->i_d.di_format = XFS_DINODE_FMT_EXTENTS;
2470 ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;
2471
2472 /* Don't attempt to replay owner changes for a deleted inode */
2473 ip->i_itemp->ili_fields &= ~(XFS_ILOG_AOWNER|XFS_ILOG_DOWNER);
2474
2475 /*
2476 * Bump the generation count so no one will be confused
2477 * by reincarnations of this inode.
2478 */
2479 VFS_I(ip)->i_generation++;
2480 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
2481
2482 if (xic.deleted)
2483 error = xfs_ifree_cluster(ip, tp, &xic);
2484
2485 return error;
2486}
2487
2488/*
2489 * This is called to unpin an inode. The caller must have the inode locked
2490 * in at least shared mode so that the buffer cannot be subsequently pinned
2491 * once someone is waiting for it to be unpinned.
2492 */
2493static void
2494xfs_iunpin(
2495 struct xfs_inode *ip)
2496{
2497 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
2498
2499 trace_xfs_inode_unpin_nowait(ip, _RET_IP_);
2500
2501 /* Give the log a push to start the unpinning I/O */
2502 xfs_log_force_lsn(ip->i_mount, ip->i_itemp->ili_last_lsn, 0, NULL);
2503
2504}
2505
2506static void
2507__xfs_iunpin_wait(
2508 struct xfs_inode *ip)
2509{
2510 wait_queue_head_t *wq = bit_waitqueue(&ip->i_flags, __XFS_IPINNED_BIT);
2511 DEFINE_WAIT_BIT(wait, &ip->i_flags, __XFS_IPINNED_BIT);
2512
2513 xfs_iunpin(ip);
2514
2515 do {
2516 prepare_to_wait(wq, &wait.wq_entry, TASK_UNINTERRUPTIBLE);
2517 if (xfs_ipincount(ip))
2518 io_schedule();
2519 } while (xfs_ipincount(ip));
2520 finish_wait(wq, &wait.wq_entry);
2521}
2522
2523void
2524xfs_iunpin_wait(
2525 struct xfs_inode *ip)
2526{
2527 if (xfs_ipincount(ip))
2528 __xfs_iunpin_wait(ip);
2529}
2530
2531/*
2532 * Removing an inode from the namespace involves removing the directory entry
2533 * and dropping the link count on the inode. Removing the directory entry can
2534 * result in locking an AGF (directory blocks were freed) and removing a link
2535 * count can result in placing the inode on an unlinked list which results in
2536 * locking an AGI.
2537 *
2538 * The big problem here is that we have an ordering constraint on AGF and AGI
2539 * locking - inode allocation locks the AGI, then can allocate a new extent for
2540 * new inodes, locking the AGF after the AGI. Similarly, freeing the inode
2541 * removes the inode from the unlinked list, requiring that we lock the AGI
2542 * first, and then freeing the inode can result in an inode chunk being freed
2543 * and hence freeing disk space requiring that we lock an AGF.
2544 *
2545 * Hence the ordering that is imposed by other parts of the code is AGI before
2546 * AGF. This means we cannot remove the directory entry before we drop the inode
2547 * reference count and put it on the unlinked list as this results in a lock
2548 * order of AGF then AGI, and this can deadlock against inode allocation and
2549 * freeing. Therefore we must drop the link counts before we remove the
2550 * directory entry.
2551 *
2552 * This is still safe from a transactional point of view - it is not until we
2553 * get to xfs_defer_finish() that we have the possibility of multiple
2554 * transactions in this operation. Hence as long as we remove the directory
2555 * entry and drop the link count in the first transaction of the remove
2556 * operation, there are no transactional constraints on the ordering here.
2557 */
2558int
2559xfs_remove(
2560 xfs_inode_t *dp,
2561 struct xfs_name *name,
2562 xfs_inode_t *ip)
2563{
2564 xfs_mount_t *mp = dp->i_mount;
2565 xfs_trans_t *tp = NULL;
2566 int is_dir = S_ISDIR(VFS_I(ip)->i_mode);
2567 int error = 0;
2568 struct xfs_defer_ops dfops;
2569 xfs_fsblock_t first_block;
2570 uint resblks;
2571
2572 trace_xfs_remove(dp, name);
2573
2574 if (XFS_FORCED_SHUTDOWN(mp))
2575 return -EIO;
2576
2577 error = xfs_qm_dqattach(dp, 0);
2578 if (error)
2579 goto std_return;
2580
2581 error = xfs_qm_dqattach(ip, 0);
2582 if (error)
2583 goto std_return;
2584
2585 /*
2586 * We try to get the real space reservation first,
2587 * allowing for directory btree deletion(s) implying
2588 * possible bmap insert(s). If we can't get the space
2589 * reservation then we use 0 instead, and avoid the bmap
2590 * btree insert(s) in the directory code by, if the bmap
2591 * insert tries to happen, instead trimming the LAST
2592 * block from the directory.
2593 */
2594 resblks = XFS_REMOVE_SPACE_RES(mp);
2595 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_remove, resblks, 0, 0, &tp);
2596 if (error == -ENOSPC) {
2597 resblks = 0;
2598 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_remove, 0, 0, 0,
2599 &tp);
2600 }
2601 if (error) {
2602 ASSERT(error != -ENOSPC);
2603 goto std_return;
2604 }
2605
2606 xfs_lock_two_inodes(dp, XFS_ILOCK_EXCL, ip, XFS_ILOCK_EXCL);
2607
2608 xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
2609 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
2610
2611 /*
2612 * If we're removing a directory perform some additional validation.
2613 */
2614 if (is_dir) {
2615 ASSERT(VFS_I(ip)->i_nlink >= 2);
2616 if (VFS_I(ip)->i_nlink != 2) {
2617 error = -ENOTEMPTY;
2618 goto out_trans_cancel;
2619 }
2620 if (!xfs_dir_isempty(ip)) {
2621 error = -ENOTEMPTY;
2622 goto out_trans_cancel;
2623 }
2624
2625 /* Drop the link from ip's "..". */
2626 error = xfs_droplink(tp, dp);
2627 if (error)
2628 goto out_trans_cancel;
2629
2630 /* Drop the "." link from ip to self. */
2631 error = xfs_droplink(tp, ip);
2632 if (error)
2633 goto out_trans_cancel;
2634 } else {
2635 /*
2636 * When removing a non-directory we need to log the parent
2637 * inode here. For a directory this is done implicitly
2638 * by the xfs_droplink call for the ".." entry.
2639 */
2640 xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
2641 }
2642 xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2643
2644 /* Drop the link from dp to ip. */
2645 error = xfs_droplink(tp, ip);
2646 if (error)
2647 goto out_trans_cancel;
2648
2649 xfs_defer_init(&dfops, &first_block);
2650 error = xfs_dir_removename(tp, dp, name, ip->i_ino,
2651 &first_block, &dfops, resblks);
2652 if (error) {
2653 ASSERT(error != -ENOENT);
2654 goto out_bmap_cancel;
2655 }
2656
2657 /*
2658 * If this is a synchronous mount, make sure that the
2659 * remove transaction goes to disk before returning to
2660 * the user.
2661 */
2662 if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
2663 xfs_trans_set_sync(tp);
2664
2665 error = xfs_defer_finish(&tp, &dfops);
2666 if (error)
2667 goto out_bmap_cancel;
2668
2669 error = xfs_trans_commit(tp);
2670 if (error)
2671 goto std_return;
2672
2673 if (is_dir && xfs_inode_is_filestream(ip))
2674 xfs_filestream_deassociate(ip);
2675
2676 return 0;
2677
2678 out_bmap_cancel:
2679 xfs_defer_cancel(&dfops);
2680 out_trans_cancel:
2681 xfs_trans_cancel(tp);
2682 std_return:
2683 return error;
2684}
2685
2686/*
2687 * Enter all inodes for a rename transaction into a sorted array.
2688 */
2689#define __XFS_SORT_INODES 5
2690STATIC void
2691xfs_sort_for_rename(
2692 struct xfs_inode *dp1, /* in: old (source) directory inode */
2693 struct xfs_inode *dp2, /* in: new (target) directory inode */
2694 struct xfs_inode *ip1, /* in: inode of old entry */
2695 struct xfs_inode *ip2, /* in: inode of new entry */
2696 struct xfs_inode *wip, /* in: whiteout inode */
2697 struct xfs_inode **i_tab,/* out: sorted array of inodes */
2698 int *num_inodes) /* in/out: inodes in array */
2699{
2700 int i, j;
2701
2702 ASSERT(*num_inodes == __XFS_SORT_INODES);
2703 memset(i_tab, 0, *num_inodes * sizeof(struct xfs_inode *));
2704
2705 /*
2706 * i_tab contains a list of pointers to inodes. We initialize
2707 * the table here & we'll sort it. We will then use it to
2708 * order the acquisition of the inode locks.
2709 *
2710 * Note that the table may contain duplicates. e.g., dp1 == dp2.
2711 */
2712 i = 0;
2713 i_tab[i++] = dp1;
2714 i_tab[i++] = dp2;
2715 i_tab[i++] = ip1;
2716 if (ip2)
2717 i_tab[i++] = ip2;
2718 if (wip)
2719 i_tab[i++] = wip;
2720 *num_inodes = i;
2721
2722 /*
2723 * Sort the elements via bubble sort. (Remember, there are at
2724 * most 5 elements to sort, so this is adequate.)
2725 */
2726 for (i = 0; i < *num_inodes; i++) {
2727 for (j = 1; j < *num_inodes; j++) {
2728 if (i_tab[j]->i_ino < i_tab[j-1]->i_ino) {
2729 struct xfs_inode *temp = i_tab[j];
2730 i_tab[j] = i_tab[j-1];
2731 i_tab[j-1] = temp;
2732 }
2733 }
2734 }
2735}
2736
2737static int
2738xfs_finish_rename(
2739 struct xfs_trans *tp,
2740 struct xfs_defer_ops *dfops)
2741{
2742 int error;
2743
2744 /*
2745 * If this is a synchronous mount, make sure that the rename transaction
2746 * goes to disk before returning to the user.
2747 */
2748 if (tp->t_mountp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
2749 xfs_trans_set_sync(tp);
2750
2751 error = xfs_defer_finish(&tp, dfops);
2752 if (error) {
2753 xfs_defer_cancel(dfops);
2754 xfs_trans_cancel(tp);
2755 return error;
2756 }
2757
2758 return xfs_trans_commit(tp);
2759}
2760
2761/*
2762 * xfs_cross_rename()
2763 *
2764 * responsible for handling RENAME_EXCHANGE flag in renameat2() sytemcall
2765 */
2766STATIC int
2767xfs_cross_rename(
2768 struct xfs_trans *tp,
2769 struct xfs_inode *dp1,
2770 struct xfs_name *name1,
2771 struct xfs_inode *ip1,
2772 struct xfs_inode *dp2,
2773 struct xfs_name *name2,
2774 struct xfs_inode *ip2,
2775 struct xfs_defer_ops *dfops,
2776 xfs_fsblock_t *first_block,
2777 int spaceres)
2778{
2779 int error = 0;
2780 int ip1_flags = 0;
2781 int ip2_flags = 0;
2782 int dp2_flags = 0;
2783
2784 /* Swap inode number for dirent in first parent */
2785 error = xfs_dir_replace(tp, dp1, name1,
2786 ip2->i_ino,
2787 first_block, dfops, spaceres);
2788 if (error)
2789 goto out_trans_abort;
2790
2791 /* Swap inode number for dirent in second parent */
2792 error = xfs_dir_replace(tp, dp2, name2,
2793 ip1->i_ino,
2794 first_block, dfops, spaceres);
2795 if (error)
2796 goto out_trans_abort;
2797
2798 /*
2799 * If we're renaming one or more directories across different parents,
2800 * update the respective ".." entries (and link counts) to match the new
2801 * parents.
2802 */
2803 if (dp1 != dp2) {
2804 dp2_flags = XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
2805
2806 if (S_ISDIR(VFS_I(ip2)->i_mode)) {
2807 error = xfs_dir_replace(tp, ip2, &xfs_name_dotdot,
2808 dp1->i_ino, first_block,
2809 dfops, spaceres);
2810 if (error)
2811 goto out_trans_abort;
2812
2813 /* transfer ip2 ".." reference to dp1 */
2814 if (!S_ISDIR(VFS_I(ip1)->i_mode)) {
2815 error = xfs_droplink(tp, dp2);
2816 if (error)
2817 goto out_trans_abort;
2818 error = xfs_bumplink(tp, dp1);
2819 if (error)
2820 goto out_trans_abort;
2821 }
2822
2823 /*
2824 * Although ip1 isn't changed here, userspace needs
2825 * to be warned about the change, so that applications
2826 * relying on it (like backup ones), will properly
2827 * notify the change
2828 */
2829 ip1_flags |= XFS_ICHGTIME_CHG;
2830 ip2_flags |= XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
2831 }
2832
2833 if (S_ISDIR(VFS_I(ip1)->i_mode)) {
2834 error = xfs_dir_replace(tp, ip1, &xfs_name_dotdot,
2835 dp2->i_ino, first_block,
2836 dfops, spaceres);
2837 if (error)
2838 goto out_trans_abort;
2839
2840 /* transfer ip1 ".." reference to dp2 */
2841 if (!S_ISDIR(VFS_I(ip2)->i_mode)) {
2842 error = xfs_droplink(tp, dp1);
2843 if (error)
2844 goto out_trans_abort;
2845 error = xfs_bumplink(tp, dp2);
2846 if (error)
2847 goto out_trans_abort;
2848 }
2849
2850 /*
2851 * Although ip2 isn't changed here, userspace needs
2852 * to be warned about the change, so that applications
2853 * relying on it (like backup ones), will properly
2854 * notify the change
2855 */
2856 ip1_flags |= XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG;
2857 ip2_flags |= XFS_ICHGTIME_CHG;
2858 }
2859 }
2860
2861 if (ip1_flags) {
2862 xfs_trans_ichgtime(tp, ip1, ip1_flags);
2863 xfs_trans_log_inode(tp, ip1, XFS_ILOG_CORE);
2864 }
2865 if (ip2_flags) {
2866 xfs_trans_ichgtime(tp, ip2, ip2_flags);
2867 xfs_trans_log_inode(tp, ip2, XFS_ILOG_CORE);
2868 }
2869 if (dp2_flags) {
2870 xfs_trans_ichgtime(tp, dp2, dp2_flags);
2871 xfs_trans_log_inode(tp, dp2, XFS_ILOG_CORE);
2872 }
2873 xfs_trans_ichgtime(tp, dp1, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2874 xfs_trans_log_inode(tp, dp1, XFS_ILOG_CORE);
2875 return xfs_finish_rename(tp, dfops);
2876
2877out_trans_abort:
2878 xfs_defer_cancel(dfops);
2879 xfs_trans_cancel(tp);
2880 return error;
2881}
2882
2883/*
2884 * xfs_rename_alloc_whiteout()
2885 *
2886 * Return a referenced, unlinked, unlocked inode that that can be used as a
2887 * whiteout in a rename transaction. We use a tmpfile inode here so that if we
2888 * crash between allocating the inode and linking it into the rename transaction
2889 * recovery will free the inode and we won't leak it.
2890 */
2891static int
2892xfs_rename_alloc_whiteout(
2893 struct xfs_inode *dp,
2894 struct xfs_inode **wip)
2895{
2896 struct xfs_inode *tmpfile;
2897 int error;
2898
2899 error = xfs_create_tmpfile(dp, S_IFCHR | WHITEOUT_MODE, &tmpfile);
2900 if (error)
2901 return error;
2902
2903 /*
2904 * Prepare the tmpfile inode as if it were created through the VFS.
2905 * Otherwise, the link increment paths will complain about nlink 0->1.
2906 * Drop the link count as done by d_tmpfile(), complete the inode setup
2907 * and flag it as linkable.
2908 */
2909 drop_nlink(VFS_I(tmpfile));
2910 xfs_setup_iops(tmpfile);
2911 xfs_finish_inode_setup(tmpfile);
2912 VFS_I(tmpfile)->i_state |= I_LINKABLE;
2913
2914 *wip = tmpfile;
2915 return 0;
2916}
2917
2918/*
2919 * xfs_rename
2920 */
2921int
2922xfs_rename(
2923 struct xfs_inode *src_dp,
2924 struct xfs_name *src_name,
2925 struct xfs_inode *src_ip,
2926 struct xfs_inode *target_dp,
2927 struct xfs_name *target_name,
2928 struct xfs_inode *target_ip,
2929 unsigned int flags)
2930{
2931 struct xfs_mount *mp = src_dp->i_mount;
2932 struct xfs_trans *tp;
2933 struct xfs_defer_ops dfops;
2934 xfs_fsblock_t first_block;
2935 struct xfs_inode *wip = NULL; /* whiteout inode */
2936 struct xfs_inode *inodes[__XFS_SORT_INODES];
2937 int num_inodes = __XFS_SORT_INODES;
2938 bool new_parent = (src_dp != target_dp);
2939 bool src_is_directory = S_ISDIR(VFS_I(src_ip)->i_mode);
2940 int spaceres;
2941 int error;
2942
2943 trace_xfs_rename(src_dp, target_dp, src_name, target_name);
2944
2945 if ((flags & RENAME_EXCHANGE) && !target_ip)
2946 return -EINVAL;
2947
2948 /*
2949 * If we are doing a whiteout operation, allocate the whiteout inode
2950 * we will be placing at the target and ensure the type is set
2951 * appropriately.
2952 */
2953 if (flags & RENAME_WHITEOUT) {
2954 ASSERT(!(flags & (RENAME_NOREPLACE | RENAME_EXCHANGE)));
2955 error = xfs_rename_alloc_whiteout(target_dp, &wip);
2956 if (error)
2957 return error;
2958
2959 /* setup target dirent info as whiteout */
2960 src_name->type = XFS_DIR3_FT_CHRDEV;
2961 }
2962
2963 xfs_sort_for_rename(src_dp, target_dp, src_ip, target_ip, wip,
2964 inodes, &num_inodes);
2965
2966 spaceres = XFS_RENAME_SPACE_RES(mp, target_name->len);
2967 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_rename, spaceres, 0, 0, &tp);
2968 if (error == -ENOSPC) {
2969 spaceres = 0;
2970 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_rename, 0, 0, 0,
2971 &tp);
2972 }
2973 if (error)
2974 goto out_release_wip;
2975
2976 /*
2977 * Attach the dquots to the inodes
2978 */
2979 error = xfs_qm_vop_rename_dqattach(inodes);
2980 if (error)
2981 goto out_trans_cancel;
2982
2983 /*
2984 * Lock all the participating inodes. Depending upon whether
2985 * the target_name exists in the target directory, and
2986 * whether the target directory is the same as the source
2987 * directory, we can lock from 2 to 4 inodes.
2988 */
2989 xfs_lock_inodes(inodes, num_inodes, XFS_ILOCK_EXCL);
2990
2991 /*
2992 * Join all the inodes to the transaction. From this point on,
2993 * we can rely on either trans_commit or trans_cancel to unlock
2994 * them.
2995 */
2996 xfs_trans_ijoin(tp, src_dp, XFS_ILOCK_EXCL);
2997 if (new_parent)
2998 xfs_trans_ijoin(tp, target_dp, XFS_ILOCK_EXCL);
2999 xfs_trans_ijoin(tp, src_ip, XFS_ILOCK_EXCL);
3000 if (target_ip)
3001 xfs_trans_ijoin(tp, target_ip, XFS_ILOCK_EXCL);
3002 if (wip)
3003 xfs_trans_ijoin(tp, wip, XFS_ILOCK_EXCL);
3004
3005 /*
3006 * If we are using project inheritance, we only allow renames
3007 * into our tree when the project IDs are the same; else the
3008 * tree quota mechanism would be circumvented.
3009 */
3010 if (unlikely((target_dp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) &&
3011 (xfs_get_projid(target_dp) != xfs_get_projid(src_ip)))) {
3012 error = -EXDEV;
3013 goto out_trans_cancel;
3014 }
3015
3016 xfs_defer_init(&dfops, &first_block);
3017
3018 /* RENAME_EXCHANGE is unique from here on. */
3019 if (flags & RENAME_EXCHANGE)
3020 return xfs_cross_rename(tp, src_dp, src_name, src_ip,
3021 target_dp, target_name, target_ip,
3022 &dfops, &first_block, spaceres);
3023
3024 /*
3025 * Set up the target.
3026 */
3027 if (target_ip == NULL) {
3028 /*
3029 * If there's no space reservation, check the entry will
3030 * fit before actually inserting it.
3031 */
3032 if (!spaceres) {
3033 error = xfs_dir_canenter(tp, target_dp, target_name);
3034 if (error)
3035 goto out_trans_cancel;
3036 }
3037 /*
3038 * If target does not exist and the rename crosses
3039 * directories, adjust the target directory link count
3040 * to account for the ".." reference from the new entry.
3041 */
3042 error = xfs_dir_createname(tp, target_dp, target_name,
3043 src_ip->i_ino, &first_block,
3044 &dfops, spaceres);
3045 if (error)
3046 goto out_bmap_cancel;
3047
3048 xfs_trans_ichgtime(tp, target_dp,
3049 XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
3050
3051 if (new_parent && src_is_directory) {
3052 error = xfs_bumplink(tp, target_dp);
3053 if (error)
3054 goto out_bmap_cancel;
3055 }
3056 } else { /* target_ip != NULL */
3057 /*
3058 * If target exists and it's a directory, check that both
3059 * target and source are directories and that target can be
3060 * destroyed, or that neither is a directory.
3061 */
3062 if (S_ISDIR(VFS_I(target_ip)->i_mode)) {
3063 /*
3064 * Make sure target dir is empty.
3065 */
3066 if (!(xfs_dir_isempty(target_ip)) ||
3067 (VFS_I(target_ip)->i_nlink > 2)) {
3068 error = -EEXIST;
3069 goto out_trans_cancel;
3070 }
3071 }
3072
3073 /*
3074 * Link the source inode under the target name.
3075 * If the source inode is a directory and we are moving
3076 * it across directories, its ".." entry will be
3077 * inconsistent until we replace that down below.
3078 *
3079 * In case there is already an entry with the same
3080 * name at the destination directory, remove it first.
3081 */
3082 error = xfs_dir_replace(tp, target_dp, target_name,
3083 src_ip->i_ino,
3084 &first_block, &dfops, spaceres);
3085 if (error)
3086 goto out_bmap_cancel;
3087
3088 xfs_trans_ichgtime(tp, target_dp,
3089 XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
3090
3091 /*
3092 * Decrement the link count on the target since the target
3093 * dir no longer points to it.
3094 */
3095 error = xfs_droplink(tp, target_ip);
3096 if (error)
3097 goto out_bmap_cancel;
3098
3099 if (src_is_directory) {
3100 /*
3101 * Drop the link from the old "." entry.
3102 */
3103 error = xfs_droplink(tp, target_ip);
3104 if (error)
3105 goto out_bmap_cancel;
3106 }
3107 } /* target_ip != NULL */
3108
3109 /*
3110 * Remove the source.
3111 */
3112 if (new_parent && src_is_directory) {
3113 /*
3114 * Rewrite the ".." entry to point to the new
3115 * directory.
3116 */
3117 error = xfs_dir_replace(tp, src_ip, &xfs_name_dotdot,
3118 target_dp->i_ino,
3119 &first_block, &dfops, spaceres);
3120 ASSERT(error != -EEXIST);
3121 if (error)
3122 goto out_bmap_cancel;
3123 }
3124
3125 /*
3126 * We always want to hit the ctime on the source inode.
3127 *
3128 * This isn't strictly required by the standards since the source
3129 * inode isn't really being changed, but old unix file systems did
3130 * it and some incremental backup programs won't work without it.
3131 */
3132 xfs_trans_ichgtime(tp, src_ip, XFS_ICHGTIME_CHG);
3133 xfs_trans_log_inode(tp, src_ip, XFS_ILOG_CORE);
3134
3135 /*
3136 * Adjust the link count on src_dp. This is necessary when
3137 * renaming a directory, either within one parent when
3138 * the target existed, or across two parent directories.
3139 */
3140 if (src_is_directory && (new_parent || target_ip != NULL)) {
3141
3142 /*
3143 * Decrement link count on src_directory since the
3144 * entry that's moved no longer points to it.
3145 */
3146 error = xfs_droplink(tp, src_dp);
3147 if (error)
3148 goto out_bmap_cancel;
3149 }
3150
3151 /*
3152 * For whiteouts, we only need to update the source dirent with the
3153 * inode number of the whiteout inode rather than removing it
3154 * altogether.
3155 */
3156 if (wip) {
3157 error = xfs_dir_replace(tp, src_dp, src_name, wip->i_ino,
3158 &first_block, &dfops, spaceres);
3159 } else
3160 error = xfs_dir_removename(tp, src_dp, src_name, src_ip->i_ino,
3161 &first_block, &dfops, spaceres);
3162 if (error)
3163 goto out_bmap_cancel;
3164
3165 /*
3166 * For whiteouts, we need to bump the link count on the whiteout inode.
3167 * This means that failures all the way up to this point leave the inode
3168 * on the unlinked list and so cleanup is a simple matter of dropping
3169 * the remaining reference to it. If we fail here after bumping the link
3170 * count, we're shutting down the filesystem so we'll never see the
3171 * intermediate state on disk.
3172 */
3173 if (wip) {
3174 ASSERT(VFS_I(wip)->i_nlink == 0);
3175 error = xfs_bumplink(tp, wip);
3176 if (error)
3177 goto out_bmap_cancel;
3178 error = xfs_iunlink_remove(tp, wip);
3179 if (error)
3180 goto out_bmap_cancel;
3181 xfs_trans_log_inode(tp, wip, XFS_ILOG_CORE);
3182
3183 /*
3184 * Now we have a real link, clear the "I'm a tmpfile" state
3185 * flag from the inode so it doesn't accidentally get misused in
3186 * future.
3187 */
3188 VFS_I(wip)->i_state &= ~I_LINKABLE;
3189 }
3190
3191 xfs_trans_ichgtime(tp, src_dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
3192 xfs_trans_log_inode(tp, src_dp, XFS_ILOG_CORE);
3193 if (new_parent)
3194 xfs_trans_log_inode(tp, target_dp, XFS_ILOG_CORE);
3195
3196 error = xfs_finish_rename(tp, &dfops);
3197 if (wip)
3198 IRELE(wip);
3199 return error;
3200
3201out_bmap_cancel:
3202 xfs_defer_cancel(&dfops);
3203out_trans_cancel:
3204 xfs_trans_cancel(tp);
3205out_release_wip:
3206 if (wip)
3207 IRELE(wip);
3208 return error;
3209}
3210
3211STATIC int
3212xfs_iflush_cluster(
3213 struct xfs_inode *ip,
3214 struct xfs_buf *bp)
3215{
3216 struct xfs_mount *mp = ip->i_mount;
3217 struct xfs_perag *pag;
3218 unsigned long first_index, mask;
3219 unsigned long inodes_per_cluster;
3220 int cilist_size;
3221 struct xfs_inode **cilist;
3222 struct xfs_inode *cip;
3223 int nr_found;
3224 int clcount = 0;
3225 int bufwasdelwri;
3226 int i;
3227
3228 pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));
3229
3230 inodes_per_cluster = mp->m_inode_cluster_size >> mp->m_sb.sb_inodelog;
3231 cilist_size = inodes_per_cluster * sizeof(xfs_inode_t *);
3232 cilist = kmem_alloc(cilist_size, KM_MAYFAIL|KM_NOFS);
3233 if (!cilist)
3234 goto out_put;
3235
3236 mask = ~(((mp->m_inode_cluster_size >> mp->m_sb.sb_inodelog)) - 1);
3237 first_index = XFS_INO_TO_AGINO(mp, ip->i_ino) & mask;
3238 rcu_read_lock();
3239 /* really need a gang lookup range call here */
3240 nr_found = radix_tree_gang_lookup(&pag->pag_ici_root, (void**)cilist,
3241 first_index, inodes_per_cluster);
3242 if (nr_found == 0)
3243 goto out_free;
3244
3245 for (i = 0; i < nr_found; i++) {
3246 cip = cilist[i];
3247 if (cip == ip)
3248 continue;
3249
3250 /*
3251 * because this is an RCU protected lookup, we could find a
3252 * recently freed or even reallocated inode during the lookup.
3253 * We need to check under the i_flags_lock for a valid inode
3254 * here. Skip it if it is not valid or the wrong inode.
3255 */
3256 spin_lock(&cip->i_flags_lock);
3257 if (!cip->i_ino ||
3258 __xfs_iflags_test(cip, XFS_ISTALE)) {
3259 spin_unlock(&cip->i_flags_lock);
3260 continue;
3261 }
3262
3263 /*
3264 * Once we fall off the end of the cluster, no point checking
3265 * any more inodes in the list because they will also all be
3266 * outside the cluster.
3267 */
3268 if ((XFS_INO_TO_AGINO(mp, cip->i_ino) & mask) != first_index) {
3269 spin_unlock(&cip->i_flags_lock);
3270 break;
3271 }
3272 spin_unlock(&cip->i_flags_lock);
3273
3274 /*
3275 * Do an un-protected check to see if the inode is dirty and
3276 * is a candidate for flushing. These checks will be repeated
3277 * later after the appropriate locks are acquired.
3278 */
3279 if (xfs_inode_clean(cip) && xfs_ipincount(cip) == 0)
3280 continue;
3281
3282 /*
3283 * Try to get locks. If any are unavailable or it is pinned,
3284 * then this inode cannot be flushed and is skipped.
3285 */
3286
3287 if (!xfs_ilock_nowait(cip, XFS_ILOCK_SHARED))
3288 continue;
3289 if (!xfs_iflock_nowait(cip)) {
3290 xfs_iunlock(cip, XFS_ILOCK_SHARED);
3291 continue;
3292 }
3293 if (xfs_ipincount(cip)) {
3294 xfs_ifunlock(cip);
3295 xfs_iunlock(cip, XFS_ILOCK_SHARED);
3296 continue;
3297 }
3298
3299
3300 /*
3301 * Check the inode number again, just to be certain we are not
3302 * racing with freeing in xfs_reclaim_inode(). See the comments
3303 * in that function for more information as to why the initial
3304 * check is not sufficient.
3305 */
3306 if (!cip->i_ino) {
3307 xfs_ifunlock(cip);
3308 xfs_iunlock(cip, XFS_ILOCK_SHARED);
3309 continue;
3310 }
3311
3312 /*
3313 * arriving here means that this inode can be flushed. First
3314 * re-check that it's dirty before flushing.
3315 */
3316 if (!xfs_inode_clean(cip)) {
3317 int error;
3318 error = xfs_iflush_int(cip, bp);
3319 if (error) {
3320 xfs_iunlock(cip, XFS_ILOCK_SHARED);
3321 goto cluster_corrupt_out;
3322 }
3323 clcount++;
3324 } else {
3325 xfs_ifunlock(cip);
3326 }
3327 xfs_iunlock(cip, XFS_ILOCK_SHARED);
3328 }
3329
3330 if (clcount) {
3331 XFS_STATS_INC(mp, xs_icluster_flushcnt);
3332 XFS_STATS_ADD(mp, xs_icluster_flushinode, clcount);
3333 }
3334
3335out_free:
3336 rcu_read_unlock();
3337 kmem_free(cilist);
3338out_put:
3339 xfs_perag_put(pag);
3340 return 0;
3341
3342
3343cluster_corrupt_out:
3344 /*
3345 * Corruption detected in the clustering loop. Invalidate the
3346 * inode buffer and shut down the filesystem.
3347 */
3348 rcu_read_unlock();
3349 /*
3350 * Clean up the buffer. If it was delwri, just release it --
3351 * brelse can handle it with no problems. If not, shut down the
3352 * filesystem before releasing the buffer.
3353 */
3354 bufwasdelwri = (bp->b_flags & _XBF_DELWRI_Q);
3355 if (bufwasdelwri)
3356 xfs_buf_relse(bp);
3357
3358 xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
3359
3360 if (!bufwasdelwri) {
3361 /*
3362 * Just like incore_relse: if we have b_iodone functions,
3363 * mark the buffer as an error and call them. Otherwise
3364 * mark it as stale and brelse.
3365 */
3366 if (bp->b_iodone) {
3367 bp->b_flags &= ~XBF_DONE;
3368 xfs_buf_stale(bp);
3369 xfs_buf_ioerror(bp, -EIO);
3370 xfs_buf_ioend(bp);
3371 } else {
3372 xfs_buf_stale(bp);
3373 xfs_buf_relse(bp);
3374 }
3375 }
3376
3377 /*
3378 * Unlocks the flush lock
3379 */
3380 xfs_iflush_abort(cip, false);
3381 kmem_free(cilist);
3382 xfs_perag_put(pag);
3383 return -EFSCORRUPTED;
3384}
3385
3386/*
3387 * Flush dirty inode metadata into the backing buffer.
3388 *
3389 * The caller must have the inode lock and the inode flush lock held. The
3390 * inode lock will still be held upon return to the caller, and the inode
3391 * flush lock will be released after the inode has reached the disk.
3392 *
3393 * The caller must write out the buffer returned in *bpp and release it.
3394 */
3395int
3396xfs_iflush(
3397 struct xfs_inode *ip,
3398 struct xfs_buf **bpp)
3399{
3400 struct xfs_mount *mp = ip->i_mount;
3401 struct xfs_buf *bp = NULL;
3402 struct xfs_dinode *dip;
3403 int error;
3404
3405 XFS_STATS_INC(mp, xs_iflush_count);
3406
3407 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
3408 ASSERT(xfs_isiflocked(ip));
3409 ASSERT(ip->i_d.di_format != XFS_DINODE_FMT_BTREE ||
3410 ip->i_d.di_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK));
3411
3412 *bpp = NULL;
3413
3414 xfs_iunpin_wait(ip);
3415
3416 /*
3417 * For stale inodes we cannot rely on the backing buffer remaining
3418 * stale in cache for the remaining life of the stale inode and so
3419 * xfs_imap_to_bp() below may give us a buffer that no longer contains
3420 * inodes below. We have to check this after ensuring the inode is
3421 * unpinned so that it is safe to reclaim the stale inode after the
3422 * flush call.
3423 */
3424 if (xfs_iflags_test(ip, XFS_ISTALE)) {
3425 xfs_ifunlock(ip);
3426 return 0;
3427 }
3428
3429 /*
3430 * This may have been unpinned because the filesystem is shutting
3431 * down forcibly. If that's the case we must not write this inode
3432 * to disk, because the log record didn't make it to disk.
3433 *
3434 * We also have to remove the log item from the AIL in this case,
3435 * as we wait for an empty AIL as part of the unmount process.
3436 */
3437 if (XFS_FORCED_SHUTDOWN(mp)) {
3438 error = -EIO;
3439 goto abort_out;
3440 }
3441
3442 /*
3443 * Get the buffer containing the on-disk inode. We are doing a try-lock
3444 * operation here, so we may get an EAGAIN error. In that case, we
3445 * simply want to return with the inode still dirty.
3446 *
3447 * If we get any other error, we effectively have a corruption situation
3448 * and we cannot flush the inode, so we treat it the same as failing
3449 * xfs_iflush_int().
3450 */
3451 error = xfs_imap_to_bp(mp, NULL, &ip->i_imap, &dip, &bp, XBF_TRYLOCK,
3452 0);
3453 if (error == -EAGAIN) {
3454 xfs_ifunlock(ip);
3455 return error;
3456 }
3457 if (error)
3458 goto corrupt_out;
3459
3460 /*
3461 * First flush out the inode that xfs_iflush was called with.
3462 */
3463 error = xfs_iflush_int(ip, bp);
3464 if (error)
3465 goto corrupt_out;
3466
3467 /*
3468 * If the buffer is pinned then push on the log now so we won't
3469 * get stuck waiting in the write for too long.
3470 */
3471 if (xfs_buf_ispinned(bp))
3472 xfs_log_force(mp, 0);
3473
3474 /*
3475 * inode clustering:
3476 * see if other inodes can be gathered into this write
3477 */
3478 error = xfs_iflush_cluster(ip, bp);
3479 if (error)
3480 goto cluster_corrupt_out;
3481
3482 *bpp = bp;
3483 return 0;
3484
3485corrupt_out:
3486 if (bp)
3487 xfs_buf_relse(bp);
3488 xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
3489cluster_corrupt_out:
3490 error = -EFSCORRUPTED;
3491abort_out:
3492 /*
3493 * Unlocks the flush lock
3494 */
3495 xfs_iflush_abort(ip, false);
3496 return error;
3497}
3498
3499/*
3500 * If there are inline format data / attr forks attached to this inode,
3501 * make sure they're not corrupt.
3502 */
3503bool
3504xfs_inode_verify_forks(
3505 struct xfs_inode *ip)
3506{
3507 struct xfs_ifork *ifp;
3508 xfs_failaddr_t fa;
3509
3510 fa = xfs_ifork_verify_data(ip, &xfs_default_ifork_ops);
3511 if (fa) {
3512 ifp = XFS_IFORK_PTR(ip, XFS_DATA_FORK);
3513 xfs_inode_verifier_error(ip, -EFSCORRUPTED, "data fork",
3514 ifp->if_u1.if_data, ifp->if_bytes, fa);
3515 return false;
3516 }
3517
3518 fa = xfs_ifork_verify_attr(ip, &xfs_default_ifork_ops);
3519 if (fa) {
3520 ifp = XFS_IFORK_PTR(ip, XFS_ATTR_FORK);
3521 xfs_inode_verifier_error(ip, -EFSCORRUPTED, "attr fork",
3522 ifp ? ifp->if_u1.if_data : NULL,
3523 ifp ? ifp->if_bytes : 0, fa);
3524 return false;
3525 }
3526 return true;
3527}
3528
3529STATIC int
3530xfs_iflush_int(
3531 struct xfs_inode *ip,
3532 struct xfs_buf *bp)
3533{
3534 struct xfs_inode_log_item *iip = ip->i_itemp;
3535 struct xfs_dinode *dip;
3536 struct xfs_mount *mp = ip->i_mount;
3537
3538 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
3539 ASSERT(xfs_isiflocked(ip));
3540 ASSERT(ip->i_d.di_format != XFS_DINODE_FMT_BTREE ||
3541 ip->i_d.di_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK));
3542 ASSERT(iip != NULL && iip->ili_fields != 0);
3543 ASSERT(ip->i_d.di_version > 1);
3544
3545 /* set *dip = inode's place in the buffer */
3546 dip = xfs_buf_offset(bp, ip->i_imap.im_boffset);
3547
3548 if (XFS_TEST_ERROR(dip->di_magic != cpu_to_be16(XFS_DINODE_MAGIC),
3549 mp, XFS_ERRTAG_IFLUSH_1)) {
3550 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3551 "%s: Bad inode %Lu magic number 0x%x, ptr "PTR_FMT,
3552 __func__, ip->i_ino, be16_to_cpu(dip->di_magic), dip);
3553 goto corrupt_out;
3554 }
3555 if (S_ISREG(VFS_I(ip)->i_mode)) {
3556 if (XFS_TEST_ERROR(
3557 (ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS) &&
3558 (ip->i_d.di_format != XFS_DINODE_FMT_BTREE),
3559 mp, XFS_ERRTAG_IFLUSH_3)) {
3560 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3561 "%s: Bad regular inode %Lu, ptr "PTR_FMT,
3562 __func__, ip->i_ino, ip);
3563 goto corrupt_out;
3564 }
3565 } else if (S_ISDIR(VFS_I(ip)->i_mode)) {
3566 if (XFS_TEST_ERROR(
3567 (ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS) &&
3568 (ip->i_d.di_format != XFS_DINODE_FMT_BTREE) &&
3569 (ip->i_d.di_format != XFS_DINODE_FMT_LOCAL),
3570 mp, XFS_ERRTAG_IFLUSH_4)) {
3571 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3572 "%s: Bad directory inode %Lu, ptr "PTR_FMT,
3573 __func__, ip->i_ino, ip);
3574 goto corrupt_out;
3575 }
3576 }
3577 if (XFS_TEST_ERROR(ip->i_d.di_nextents + ip->i_d.di_anextents >
3578 ip->i_d.di_nblocks, mp, XFS_ERRTAG_IFLUSH_5)) {
3579 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3580 "%s: detected corrupt incore inode %Lu, "
3581 "total extents = %d, nblocks = %Ld, ptr "PTR_FMT,
3582 __func__, ip->i_ino,
3583 ip->i_d.di_nextents + ip->i_d.di_anextents,
3584 ip->i_d.di_nblocks, ip);
3585 goto corrupt_out;
3586 }
3587 if (XFS_TEST_ERROR(ip->i_d.di_forkoff > mp->m_sb.sb_inodesize,
3588 mp, XFS_ERRTAG_IFLUSH_6)) {
3589 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3590 "%s: bad inode %Lu, forkoff 0x%x, ptr "PTR_FMT,
3591 __func__, ip->i_ino, ip->i_d.di_forkoff, ip);
3592 goto corrupt_out;
3593 }
3594
3595 /*
3596 * Inode item log recovery for v2 inodes are dependent on the
3597 * di_flushiter count for correct sequencing. We bump the flush
3598 * iteration count so we can detect flushes which postdate a log record
3599 * during recovery. This is redundant as we now log every change and
3600 * hence this can't happen but we need to still do it to ensure
3601 * backwards compatibility with old kernels that predate logging all
3602 * inode changes.
3603 */
3604 if (ip->i_d.di_version < 3)
3605 ip->i_d.di_flushiter++;
3606
3607 /* Check the inline fork data before we write out. */
3608 if (!xfs_inode_verify_forks(ip))
3609 goto corrupt_out;
3610
3611 /*
3612 * Copy the dirty parts of the inode into the on-disk inode. We always
3613 * copy out the core of the inode, because if the inode is dirty at all
3614 * the core must be.
3615 */
3616 xfs_inode_to_disk(ip, dip, iip->ili_item.li_lsn);
3617
3618 /* Wrap, we never let the log put out DI_MAX_FLUSH */
3619 if (ip->i_d.di_flushiter == DI_MAX_FLUSH)
3620 ip->i_d.di_flushiter = 0;
3621
3622 xfs_iflush_fork(ip, dip, iip, XFS_DATA_FORK);
3623 if (XFS_IFORK_Q(ip))
3624 xfs_iflush_fork(ip, dip, iip, XFS_ATTR_FORK);
3625 xfs_inobp_check(mp, bp);
3626
3627 /*
3628 * We've recorded everything logged in the inode, so we'd like to clear
3629 * the ili_fields bits so we don't log and flush things unnecessarily.
3630 * However, we can't stop logging all this information until the data
3631 * we've copied into the disk buffer is written to disk. If we did we
3632 * might overwrite the copy of the inode in the log with all the data
3633 * after re-logging only part of it, and in the face of a crash we
3634 * wouldn't have all the data we need to recover.
3635 *
3636 * What we do is move the bits to the ili_last_fields field. When
3637 * logging the inode, these bits are moved back to the ili_fields field.
3638 * In the xfs_iflush_done() routine we clear ili_last_fields, since we
3639 * know that the information those bits represent is permanently on
3640 * disk. As long as the flush completes before the inode is logged
3641 * again, then both ili_fields and ili_last_fields will be cleared.
3642 *
3643 * We can play with the ili_fields bits here, because the inode lock
3644 * must be held exclusively in order to set bits there and the flush
3645 * lock protects the ili_last_fields bits. Set ili_logged so the flush
3646 * done routine can tell whether or not to look in the AIL. Also, store
3647 * the current LSN of the inode so that we can tell whether the item has
3648 * moved in the AIL from xfs_iflush_done(). In order to read the lsn we
3649 * need the AIL lock, because it is a 64 bit value that cannot be read
3650 * atomically.
3651 */
3652 iip->ili_last_fields = iip->ili_fields;
3653 iip->ili_fields = 0;
3654 iip->ili_fsync_fields = 0;
3655 iip->ili_logged = 1;
3656
3657 xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn,
3658 &iip->ili_item.li_lsn);
3659
3660 /*
3661 * Attach the function xfs_iflush_done to the inode's
3662 * buffer. This will remove the inode from the AIL
3663 * and unlock the inode's flush lock when the inode is
3664 * completely written to disk.
3665 */
3666 xfs_buf_attach_iodone(bp, xfs_iflush_done, &iip->ili_item);
3667
3668 /* generate the checksum. */
3669 xfs_dinode_calc_crc(mp, dip);
3670
3671 ASSERT(!list_empty(&bp->b_li_list));
3672 ASSERT(bp->b_iodone != NULL);
3673 return 0;
3674
3675corrupt_out:
3676 return -EFSCORRUPTED;
3677}