1 /*
2 * Copyright (c) 2000-2006 Silicon Graphics, Inc.
3 * All Rights Reserved.
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it would be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
17 */
18 #include <linux/log2.h>
19
20 #include "xfs.h"
21 #include "xfs_fs.h"
22 #include "xfs_shared.h"
23 #include "xfs_format.h"
24 #include "xfs_log_format.h"
25 #include "xfs_trans_resv.h"
26 #include "xfs_inum.h"
27 #include "xfs_sb.h"
28 #include "xfs_ag.h"
29 #include "xfs_mount.h"
30 #include "xfs_inode.h"
31 #include "xfs_da_format.h"
32 #include "xfs_da_btree.h"
33 #include "xfs_dir2.h"
34 #include "xfs_attr_sf.h"
35 #include "xfs_attr.h"
36 #include "xfs_trans_space.h"
37 #include "xfs_trans.h"
38 #include "xfs_buf_item.h"
39 #include "xfs_inode_item.h"
40 #include "xfs_ialloc.h"
41 #include "xfs_bmap.h"
42 #include "xfs_bmap_util.h"
43 #include "xfs_error.h"
44 #include "xfs_quota.h"
45 #include "xfs_filestream.h"
46 #include "xfs_cksum.h"
47 #include "xfs_trace.h"
48 #include "xfs_icache.h"
49 #include "xfs_symlink.h"
50 #include "xfs_trans_priv.h"
51 #include "xfs_log.h"
52 #include "xfs_bmap_btree.h"
53
54 kmem_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
62 STATIC int xfs_iflush_int(xfs_inode_t *, xfs_buf_t *);
63
64 STATIC int xfs_iunlink_remove(xfs_trans_t *, xfs_inode_t *);
65
66 /*
67 * helper function to extract extent size hint from inode
68 */
69 xfs_extlen_t
xfs_get_extsz_hint(struct xfs_inode * ip)70 xfs_get_extsz_hint(
71 struct xfs_inode *ip)
72 {
73 if ((ip->i_d.di_flags & XFS_DIFLAG_EXTSIZE) && ip->i_d.di_extsize)
74 return ip->i_d.di_extsize;
75 if (XFS_IS_REALTIME_INODE(ip))
76 return ip->i_mount->m_sb.sb_rextsize;
77 return 0;
78 }
79
80 /*
81 * These two are wrapper routines around the xfs_ilock() routine used to
82 * centralize some grungy code. They are used in places that wish to lock the
83 * inode solely for reading the extents. The reason these places can't just
84 * call xfs_ilock(ip, XFS_ILOCK_SHARED) is that the inode lock also guards to
85 * bringing in of the extents from disk for a file in b-tree format. If the
86 * inode is in b-tree format, then we need to lock the inode exclusively until
87 * the extents are read in. Locking it exclusively all the time would limit
88 * our parallelism unnecessarily, though. What we do instead is check to see
89 * if the extents have been read in yet, and only lock the inode exclusively
90 * if they have not.
91 *
92 * The functions return a value which should be given to the corresponding
93 * xfs_iunlock() call.
94 */
95 uint
xfs_ilock_data_map_shared(struct xfs_inode * ip)96 xfs_ilock_data_map_shared(
97 struct xfs_inode *ip)
98 {
99 uint lock_mode = XFS_ILOCK_SHARED;
100
101 if (ip->i_d.di_format == XFS_DINODE_FMT_BTREE &&
102 (ip->i_df.if_flags & XFS_IFEXTENTS) == 0)
103 lock_mode = XFS_ILOCK_EXCL;
104 xfs_ilock(ip, lock_mode);
105 return lock_mode;
106 }
107
108 uint
xfs_ilock_attr_map_shared(struct xfs_inode * ip)109 xfs_ilock_attr_map_shared(
110 struct xfs_inode *ip)
111 {
112 uint lock_mode = XFS_ILOCK_SHARED;
113
114 if (ip->i_d.di_aformat == XFS_DINODE_FMT_BTREE &&
115 (ip->i_afp->if_flags & XFS_IFEXTENTS) == 0)
116 lock_mode = XFS_ILOCK_EXCL;
117 xfs_ilock(ip, lock_mode);
118 return lock_mode;
119 }
120
121 /*
122 * The xfs inode contains 2 locks: a multi-reader lock called the
123 * i_iolock and a multi-reader lock called the i_lock. This routine
124 * allows either or both of the locks to be obtained.
125 *
126 * The 2 locks should always be ordered so that the IO lock is
127 * obtained first in order to prevent deadlock.
128 *
129 * ip -- the inode being locked
130 * lock_flags -- this parameter indicates the inode's locks
131 * to be locked. It can be:
132 * XFS_IOLOCK_SHARED,
133 * XFS_IOLOCK_EXCL,
134 * XFS_ILOCK_SHARED,
135 * XFS_ILOCK_EXCL,
136 * XFS_IOLOCK_SHARED | XFS_ILOCK_SHARED,
137 * XFS_IOLOCK_SHARED | XFS_ILOCK_EXCL,
138 * XFS_IOLOCK_EXCL | XFS_ILOCK_SHARED,
139 * XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL
140 */
141 void
xfs_ilock(xfs_inode_t * ip,uint lock_flags)142 xfs_ilock(
143 xfs_inode_t *ip,
144 uint lock_flags)
145 {
146 trace_xfs_ilock(ip, lock_flags, _RET_IP_);
147
148 /*
149 * You can't set both SHARED and EXCL for the same lock,
150 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
151 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
152 */
153 ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
154 (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
155 ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
156 (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
157 ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_DEP_MASK)) == 0);
158
159 if (lock_flags & XFS_IOLOCK_EXCL)
160 mrupdate_nested(&ip->i_iolock, XFS_IOLOCK_DEP(lock_flags));
161 else if (lock_flags & XFS_IOLOCK_SHARED)
162 mraccess_nested(&ip->i_iolock, XFS_IOLOCK_DEP(lock_flags));
163
164 if (lock_flags & XFS_ILOCK_EXCL)
165 mrupdate_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
166 else if (lock_flags & XFS_ILOCK_SHARED)
167 mraccess_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags));
168 }
169
170 /*
171 * This is just like xfs_ilock(), except that the caller
172 * is guaranteed not to sleep. It returns 1 if it gets
173 * the requested locks and 0 otherwise. If the IO lock is
174 * obtained but the inode lock cannot be, then the IO lock
175 * is dropped before returning.
176 *
177 * ip -- the inode being locked
178 * lock_flags -- this parameter indicates the inode's locks to be
179 * to be locked. See the comment for xfs_ilock() for a list
180 * of valid values.
181 */
182 int
xfs_ilock_nowait(xfs_inode_t * ip,uint lock_flags)183 xfs_ilock_nowait(
184 xfs_inode_t *ip,
185 uint lock_flags)
186 {
187 trace_xfs_ilock_nowait(ip, lock_flags, _RET_IP_);
188
189 /*
190 * You can't set both SHARED and EXCL for the same lock,
191 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
192 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
193 */
194 ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
195 (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
196 ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
197 (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
198 ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_DEP_MASK)) == 0);
199
200 if (lock_flags & XFS_IOLOCK_EXCL) {
201 if (!mrtryupdate(&ip->i_iolock))
202 goto out;
203 } else if (lock_flags & XFS_IOLOCK_SHARED) {
204 if (!mrtryaccess(&ip->i_iolock))
205 goto out;
206 }
207 if (lock_flags & XFS_ILOCK_EXCL) {
208 if (!mrtryupdate(&ip->i_lock))
209 goto out_undo_iolock;
210 } else if (lock_flags & XFS_ILOCK_SHARED) {
211 if (!mrtryaccess(&ip->i_lock))
212 goto out_undo_iolock;
213 }
214 return 1;
215
216 out_undo_iolock:
217 if (lock_flags & XFS_IOLOCK_EXCL)
218 mrunlock_excl(&ip->i_iolock);
219 else if (lock_flags & XFS_IOLOCK_SHARED)
220 mrunlock_shared(&ip->i_iolock);
221 out:
222 return 0;
223 }
224
225 /*
226 * xfs_iunlock() is used to drop the inode locks acquired with
227 * xfs_ilock() and xfs_ilock_nowait(). The caller must pass
228 * in the flags given to xfs_ilock() or xfs_ilock_nowait() so
229 * that we know which locks to drop.
230 *
231 * ip -- the inode being unlocked
232 * lock_flags -- this parameter indicates the inode's locks to be
233 * to be unlocked. See the comment for xfs_ilock() for a list
234 * of valid values for this parameter.
235 *
236 */
237 void
xfs_iunlock(xfs_inode_t * ip,uint lock_flags)238 xfs_iunlock(
239 xfs_inode_t *ip,
240 uint lock_flags)
241 {
242 /*
243 * You can't set both SHARED and EXCL for the same lock,
244 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
245 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
246 */
247 ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) !=
248 (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
249 ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
250 (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
251 ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_DEP_MASK)) == 0);
252 ASSERT(lock_flags != 0);
253
254 if (lock_flags & XFS_IOLOCK_EXCL)
255 mrunlock_excl(&ip->i_iolock);
256 else if (lock_flags & XFS_IOLOCK_SHARED)
257 mrunlock_shared(&ip->i_iolock);
258
259 if (lock_flags & XFS_ILOCK_EXCL)
260 mrunlock_excl(&ip->i_lock);
261 else if (lock_flags & XFS_ILOCK_SHARED)
262 mrunlock_shared(&ip->i_lock);
263
264 trace_xfs_iunlock(ip, lock_flags, _RET_IP_);
265 }
266
267 /*
268 * give up write locks. the i/o lock cannot be held nested
269 * if it is being demoted.
270 */
271 void
xfs_ilock_demote(xfs_inode_t * ip,uint lock_flags)272 xfs_ilock_demote(
273 xfs_inode_t *ip,
274 uint lock_flags)
275 {
276 ASSERT(lock_flags & (XFS_IOLOCK_EXCL|XFS_ILOCK_EXCL));
277 ASSERT((lock_flags & ~(XFS_IOLOCK_EXCL|XFS_ILOCK_EXCL)) == 0);
278
279 if (lock_flags & XFS_ILOCK_EXCL)
280 mrdemote(&ip->i_lock);
281 if (lock_flags & XFS_IOLOCK_EXCL)
282 mrdemote(&ip->i_iolock);
283
284 trace_xfs_ilock_demote(ip, lock_flags, _RET_IP_);
285 }
286
287 #if defined(DEBUG) || defined(XFS_WARN)
288 int
xfs_isilocked(xfs_inode_t * ip,uint lock_flags)289 xfs_isilocked(
290 xfs_inode_t *ip,
291 uint lock_flags)
292 {
293 if (lock_flags & (XFS_ILOCK_EXCL|XFS_ILOCK_SHARED)) {
294 if (!(lock_flags & XFS_ILOCK_SHARED))
295 return !!ip->i_lock.mr_writer;
296 return rwsem_is_locked(&ip->i_lock.mr_lock);
297 }
298
299 if (lock_flags & (XFS_IOLOCK_EXCL|XFS_IOLOCK_SHARED)) {
300 if (!(lock_flags & XFS_IOLOCK_SHARED))
301 return !!ip->i_iolock.mr_writer;
302 return rwsem_is_locked(&ip->i_iolock.mr_lock);
303 }
304
305 ASSERT(0);
306 return 0;
307 }
308 #endif
309
310 #ifdef DEBUG
311 int xfs_locked_n;
312 int xfs_small_retries;
313 int xfs_middle_retries;
314 int xfs_lots_retries;
315 int xfs_lock_delays;
316 #endif
317
318 /*
319 * Bump the subclass so xfs_lock_inodes() acquires each lock with
320 * a different value
321 */
322 static inline int
xfs_lock_inumorder(int lock_mode,int subclass)323 xfs_lock_inumorder(int lock_mode, int subclass)
324 {
325 if (lock_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL))
326 lock_mode |= (subclass + XFS_LOCK_INUMORDER) << XFS_IOLOCK_SHIFT;
327 if (lock_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL))
328 lock_mode |= (subclass + XFS_LOCK_INUMORDER) << XFS_ILOCK_SHIFT;
329
330 return lock_mode;
331 }
332
333 /*
334 * The following routine will lock n inodes in exclusive mode.
335 * We assume the caller calls us with the inodes in i_ino order.
336 *
337 * We need to detect deadlock where an inode that we lock
338 * is in the AIL and we start waiting for another inode that is locked
339 * by a thread in a long running transaction (such as truncate). This can
340 * result in deadlock since the long running trans might need to wait
341 * for the inode we just locked in order to push the tail and free space
342 * in the log.
343 */
344 void
xfs_lock_inodes(xfs_inode_t ** ips,int inodes,uint lock_mode)345 xfs_lock_inodes(
346 xfs_inode_t **ips,
347 int inodes,
348 uint lock_mode)
349 {
350 int attempts = 0, i, j, try_lock;
351 xfs_log_item_t *lp;
352
353 ASSERT(ips && (inodes >= 2)); /* we need at least two */
354
355 try_lock = 0;
356 i = 0;
357
358 again:
359 for (; i < inodes; i++) {
360 ASSERT(ips[i]);
361
362 if (i && (ips[i] == ips[i-1])) /* Already locked */
363 continue;
364
365 /*
366 * If try_lock is not set yet, make sure all locked inodes
367 * are not in the AIL.
368 * If any are, set try_lock to be used later.
369 */
370
371 if (!try_lock) {
372 for (j = (i - 1); j >= 0 && !try_lock; j--) {
373 lp = (xfs_log_item_t *)ips[j]->i_itemp;
374 if (lp && (lp->li_flags & XFS_LI_IN_AIL)) {
375 try_lock++;
376 }
377 }
378 }
379
380 /*
381 * If any of the previous locks we have locked is in the AIL,
382 * we must TRY to get the second and subsequent locks. If
383 * we can't get any, we must release all we have
384 * and try again.
385 */
386
387 if (try_lock) {
388 /* try_lock must be 0 if i is 0. */
389 /*
390 * try_lock means we have an inode locked
391 * that is in the AIL.
392 */
393 ASSERT(i != 0);
394 if (!xfs_ilock_nowait(ips[i], xfs_lock_inumorder(lock_mode, i))) {
395 attempts++;
396
397 /*
398 * Unlock all previous guys and try again.
399 * xfs_iunlock will try to push the tail
400 * if the inode is in the AIL.
401 */
402
403 for(j = i - 1; j >= 0; j--) {
404
405 /*
406 * Check to see if we've already
407 * unlocked this one.
408 * Not the first one going back,
409 * and the inode ptr is the same.
410 */
411 if ((j != (i - 1)) && ips[j] ==
412 ips[j+1])
413 continue;
414
415 xfs_iunlock(ips[j], lock_mode);
416 }
417
418 if ((attempts % 5) == 0) {
419 delay(1); /* Don't just spin the CPU */
420 #ifdef DEBUG
421 xfs_lock_delays++;
422 #endif
423 }
424 i = 0;
425 try_lock = 0;
426 goto again;
427 }
428 } else {
429 xfs_ilock(ips[i], xfs_lock_inumorder(lock_mode, i));
430 }
431 }
432
433 #ifdef DEBUG
434 if (attempts) {
435 if (attempts < 5) xfs_small_retries++;
436 else if (attempts < 100) xfs_middle_retries++;
437 else xfs_lots_retries++;
438 } else {
439 xfs_locked_n++;
440 }
441 #endif
442 }
443
444 /*
445 * xfs_lock_two_inodes() can only be used to lock one type of lock
446 * at a time - the iolock or the ilock, but not both at once. If
447 * we lock both at once, lockdep will report false positives saying
448 * we have violated locking orders.
449 */
450 void
xfs_lock_two_inodes(xfs_inode_t * ip0,xfs_inode_t * ip1,uint lock_mode)451 xfs_lock_two_inodes(
452 xfs_inode_t *ip0,
453 xfs_inode_t *ip1,
454 uint lock_mode)
455 {
456 xfs_inode_t *temp;
457 int attempts = 0;
458 xfs_log_item_t *lp;
459
460 if (lock_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL))
461 ASSERT((lock_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)) == 0);
462 ASSERT(ip0->i_ino != ip1->i_ino);
463
464 if (ip0->i_ino > ip1->i_ino) {
465 temp = ip0;
466 ip0 = ip1;
467 ip1 = temp;
468 }
469
470 again:
471 xfs_ilock(ip0, xfs_lock_inumorder(lock_mode, 0));
472
473 /*
474 * If the first lock we have locked is in the AIL, we must TRY to get
475 * the second lock. If we can't get it, we must release the first one
476 * and try again.
477 */
478 lp = (xfs_log_item_t *)ip0->i_itemp;
479 if (lp && (lp->li_flags & XFS_LI_IN_AIL)) {
480 if (!xfs_ilock_nowait(ip1, xfs_lock_inumorder(lock_mode, 1))) {
481 xfs_iunlock(ip0, lock_mode);
482 if ((++attempts % 5) == 0)
483 delay(1); /* Don't just spin the CPU */
484 goto again;
485 }
486 } else {
487 xfs_ilock(ip1, xfs_lock_inumorder(lock_mode, 1));
488 }
489 }
490
491
492 void
__xfs_iflock(struct xfs_inode * ip)493 __xfs_iflock(
494 struct xfs_inode *ip)
495 {
496 wait_queue_head_t *wq = bit_waitqueue(&ip->i_flags, __XFS_IFLOCK_BIT);
497 DEFINE_WAIT_BIT(wait, &ip->i_flags, __XFS_IFLOCK_BIT);
498
499 do {
500 prepare_to_wait_exclusive(wq, &wait.wait, TASK_UNINTERRUPTIBLE);
501 if (xfs_isiflocked(ip))
502 io_schedule();
503 } while (!xfs_iflock_nowait(ip));
504
505 finish_wait(wq, &wait.wait);
506 }
507
508 STATIC uint
_xfs_dic2xflags(__uint16_t di_flags)509 _xfs_dic2xflags(
510 __uint16_t di_flags)
511 {
512 uint flags = 0;
513
514 if (di_flags & XFS_DIFLAG_ANY) {
515 if (di_flags & XFS_DIFLAG_REALTIME)
516 flags |= XFS_XFLAG_REALTIME;
517 if (di_flags & XFS_DIFLAG_PREALLOC)
518 flags |= XFS_XFLAG_PREALLOC;
519 if (di_flags & XFS_DIFLAG_IMMUTABLE)
520 flags |= XFS_XFLAG_IMMUTABLE;
521 if (di_flags & XFS_DIFLAG_APPEND)
522 flags |= XFS_XFLAG_APPEND;
523 if (di_flags & XFS_DIFLAG_SYNC)
524 flags |= XFS_XFLAG_SYNC;
525 if (di_flags & XFS_DIFLAG_NOATIME)
526 flags |= XFS_XFLAG_NOATIME;
527 if (di_flags & XFS_DIFLAG_NODUMP)
528 flags |= XFS_XFLAG_NODUMP;
529 if (di_flags & XFS_DIFLAG_RTINHERIT)
530 flags |= XFS_XFLAG_RTINHERIT;
531 if (di_flags & XFS_DIFLAG_PROJINHERIT)
532 flags |= XFS_XFLAG_PROJINHERIT;
533 if (di_flags & XFS_DIFLAG_NOSYMLINKS)
534 flags |= XFS_XFLAG_NOSYMLINKS;
535 if (di_flags & XFS_DIFLAG_EXTSIZE)
536 flags |= XFS_XFLAG_EXTSIZE;
537 if (di_flags & XFS_DIFLAG_EXTSZINHERIT)
538 flags |= XFS_XFLAG_EXTSZINHERIT;
539 if (di_flags & XFS_DIFLAG_NODEFRAG)
540 flags |= XFS_XFLAG_NODEFRAG;
541 if (di_flags & XFS_DIFLAG_FILESTREAM)
542 flags |= XFS_XFLAG_FILESTREAM;
543 }
544
545 return flags;
546 }
547
548 uint
xfs_ip2xflags(xfs_inode_t * ip)549 xfs_ip2xflags(
550 xfs_inode_t *ip)
551 {
552 xfs_icdinode_t *dic = &ip->i_d;
553
554 return _xfs_dic2xflags(dic->di_flags) |
555 (XFS_IFORK_Q(ip) ? XFS_XFLAG_HASATTR : 0);
556 }
557
558 uint
xfs_dic2xflags(xfs_dinode_t * dip)559 xfs_dic2xflags(
560 xfs_dinode_t *dip)
561 {
562 return _xfs_dic2xflags(be16_to_cpu(dip->di_flags)) |
563 (XFS_DFORK_Q(dip) ? XFS_XFLAG_HASATTR : 0);
564 }
565
566 /*
567 * Lookups up an inode from "name". If ci_name is not NULL, then a CI match
568 * is allowed, otherwise it has to be an exact match. If a CI match is found,
569 * ci_name->name will point to a the actual name (caller must free) or
570 * will be set to NULL if an exact match is found.
571 */
572 int
xfs_lookup(xfs_inode_t * dp,struct xfs_name * name,xfs_inode_t ** ipp,struct xfs_name * ci_name)573 xfs_lookup(
574 xfs_inode_t *dp,
575 struct xfs_name *name,
576 xfs_inode_t **ipp,
577 struct xfs_name *ci_name)
578 {
579 xfs_ino_t inum;
580 int error;
581 uint lock_mode;
582
583 trace_xfs_lookup(dp, name);
584
585 if (XFS_FORCED_SHUTDOWN(dp->i_mount))
586 return -EIO;
587
588 lock_mode = xfs_ilock_data_map_shared(dp);
589 error = xfs_dir_lookup(NULL, dp, name, &inum, ci_name);
590 xfs_iunlock(dp, lock_mode);
591
592 if (error)
593 goto out;
594
595 error = xfs_iget(dp->i_mount, NULL, inum, 0, 0, ipp);
596 if (error)
597 goto out_free_name;
598
599 return 0;
600
601 out_free_name:
602 if (ci_name)
603 kmem_free(ci_name->name);
604 out:
605 *ipp = NULL;
606 return error;
607 }
608
609 /*
610 * Allocate an inode on disk and return a copy of its in-core version.
611 * The in-core inode is locked exclusively. Set mode, nlink, and rdev
612 * appropriately within the inode. The uid and gid for the inode are
613 * set according to the contents of the given cred structure.
614 *
615 * Use xfs_dialloc() to allocate the on-disk inode. If xfs_dialloc()
616 * has a free inode available, call xfs_iget() to obtain the in-core
617 * version of the allocated inode. Finally, fill in the inode and
618 * log its initial contents. In this case, ialloc_context would be
619 * set to NULL.
620 *
621 * If xfs_dialloc() does not have an available inode, it will replenish
622 * its supply by doing an allocation. Since we can only do one
623 * allocation within a transaction without deadlocks, we must commit
624 * the current transaction before returning the inode itself.
625 * In this case, therefore, we will set ialloc_context and return.
626 * The caller should then commit the current transaction, start a new
627 * transaction, and call xfs_ialloc() again to actually get the inode.
628 *
629 * To ensure that some other process does not grab the inode that
630 * was allocated during the first call to xfs_ialloc(), this routine
631 * also returns the [locked] bp pointing to the head of the freelist
632 * as ialloc_context. The caller should hold this buffer across
633 * the commit and pass it back into this routine on the second call.
634 *
635 * If we are allocating quota inodes, we do not have a parent inode
636 * to attach to or associate with (i.e. pip == NULL) because they
637 * are not linked into the directory structure - they are attached
638 * directly to the superblock - and so have no parent.
639 */
640 int
xfs_ialloc(xfs_trans_t * tp,xfs_inode_t * pip,umode_t mode,xfs_nlink_t nlink,xfs_dev_t rdev,prid_t prid,int okalloc,xfs_buf_t ** ialloc_context,xfs_inode_t ** ipp)641 xfs_ialloc(
642 xfs_trans_t *tp,
643 xfs_inode_t *pip,
644 umode_t mode,
645 xfs_nlink_t nlink,
646 xfs_dev_t rdev,
647 prid_t prid,
648 int okalloc,
649 xfs_buf_t **ialloc_context,
650 xfs_inode_t **ipp)
651 {
652 struct xfs_mount *mp = tp->t_mountp;
653 xfs_ino_t ino;
654 xfs_inode_t *ip;
655 uint flags;
656 int error;
657 struct timespec tv;
658
659 /*
660 * Call the space management code to pick
661 * the on-disk inode to be allocated.
662 */
663 error = xfs_dialloc(tp, pip ? pip->i_ino : 0, mode, okalloc,
664 ialloc_context, &ino);
665 if (error)
666 return error;
667 if (*ialloc_context || ino == NULLFSINO) {
668 *ipp = NULL;
669 return 0;
670 }
671 ASSERT(*ialloc_context == NULL);
672
673 /*
674 * Get the in-core inode with the lock held exclusively.
675 * This is because we're setting fields here we need
676 * to prevent others from looking at until we're done.
677 */
678 error = xfs_iget(mp, tp, ino, XFS_IGET_CREATE,
679 XFS_ILOCK_EXCL, &ip);
680 if (error)
681 return error;
682 ASSERT(ip != NULL);
683
684 /*
685 * We always convert v1 inodes to v2 now - we only support filesystems
686 * with >= v2 inode capability, so there is no reason for ever leaving
687 * an inode in v1 format.
688 */
689 if (ip->i_d.di_version == 1)
690 ip->i_d.di_version = 2;
691
692 ip->i_d.di_mode = mode;
693 ip->i_d.di_onlink = 0;
694 ip->i_d.di_nlink = nlink;
695 ASSERT(ip->i_d.di_nlink == nlink);
696 ip->i_d.di_uid = xfs_kuid_to_uid(current_fsuid());
697 ip->i_d.di_gid = xfs_kgid_to_gid(current_fsgid());
698 xfs_set_projid(ip, prid);
699 memset(&(ip->i_d.di_pad[0]), 0, sizeof(ip->i_d.di_pad));
700
701 if (pip && XFS_INHERIT_GID(pip)) {
702 ip->i_d.di_gid = pip->i_d.di_gid;
703 if ((pip->i_d.di_mode & S_ISGID) && S_ISDIR(mode)) {
704 ip->i_d.di_mode |= S_ISGID;
705 }
706 }
707
708 /*
709 * If the group ID of the new file does not match the effective group
710 * ID or one of the supplementary group IDs, the S_ISGID bit is cleared
711 * (and only if the irix_sgid_inherit compatibility variable is set).
712 */
713 if ((irix_sgid_inherit) &&
714 (ip->i_d.di_mode & S_ISGID) &&
715 (!in_group_p(xfs_gid_to_kgid(ip->i_d.di_gid)))) {
716 ip->i_d.di_mode &= ~S_ISGID;
717 }
718
719 ip->i_d.di_size = 0;
720 ip->i_d.di_nextents = 0;
721 ASSERT(ip->i_d.di_nblocks == 0);
722
723 tv = current_fs_time(mp->m_super);
724 ip->i_d.di_mtime.t_sec = (__int32_t)tv.tv_sec;
725 ip->i_d.di_mtime.t_nsec = (__int32_t)tv.tv_nsec;
726 ip->i_d.di_atime = ip->i_d.di_mtime;
727 ip->i_d.di_ctime = ip->i_d.di_mtime;
728
729 /*
730 * di_gen will have been taken care of in xfs_iread.
731 */
732 ip->i_d.di_extsize = 0;
733 ip->i_d.di_dmevmask = 0;
734 ip->i_d.di_dmstate = 0;
735 ip->i_d.di_flags = 0;
736
737 if (ip->i_d.di_version == 3) {
738 ASSERT(ip->i_d.di_ino == ino);
739 ASSERT(uuid_equal(&ip->i_d.di_uuid, &mp->m_sb.sb_uuid));
740 ip->i_d.di_crc = 0;
741 ip->i_d.di_changecount = 1;
742 ip->i_d.di_lsn = 0;
743 ip->i_d.di_flags2 = 0;
744 memset(&(ip->i_d.di_pad2[0]), 0, sizeof(ip->i_d.di_pad2));
745 ip->i_d.di_crtime = ip->i_d.di_mtime;
746 }
747
748
749 flags = XFS_ILOG_CORE;
750 switch (mode & S_IFMT) {
751 case S_IFIFO:
752 case S_IFCHR:
753 case S_IFBLK:
754 case S_IFSOCK:
755 ip->i_d.di_format = XFS_DINODE_FMT_DEV;
756 ip->i_df.if_u2.if_rdev = rdev;
757 ip->i_df.if_flags = 0;
758 flags |= XFS_ILOG_DEV;
759 break;
760 case S_IFREG:
761 case S_IFDIR:
762 if (pip && (pip->i_d.di_flags & XFS_DIFLAG_ANY)) {
763 uint di_flags = 0;
764
765 if (S_ISDIR(mode)) {
766 if (pip->i_d.di_flags & XFS_DIFLAG_RTINHERIT)
767 di_flags |= XFS_DIFLAG_RTINHERIT;
768 if (pip->i_d.di_flags & XFS_DIFLAG_EXTSZINHERIT) {
769 di_flags |= XFS_DIFLAG_EXTSZINHERIT;
770 ip->i_d.di_extsize = pip->i_d.di_extsize;
771 }
772 if (pip->i_d.di_flags & XFS_DIFLAG_PROJINHERIT)
773 di_flags |= XFS_DIFLAG_PROJINHERIT;
774 } else if (S_ISREG(mode)) {
775 if (pip->i_d.di_flags & XFS_DIFLAG_RTINHERIT)
776 di_flags |= XFS_DIFLAG_REALTIME;
777 if (pip->i_d.di_flags & XFS_DIFLAG_EXTSZINHERIT) {
778 di_flags |= XFS_DIFLAG_EXTSIZE;
779 ip->i_d.di_extsize = pip->i_d.di_extsize;
780 }
781 }
782 if ((pip->i_d.di_flags & XFS_DIFLAG_NOATIME) &&
783 xfs_inherit_noatime)
784 di_flags |= XFS_DIFLAG_NOATIME;
785 if ((pip->i_d.di_flags & XFS_DIFLAG_NODUMP) &&
786 xfs_inherit_nodump)
787 di_flags |= XFS_DIFLAG_NODUMP;
788 if ((pip->i_d.di_flags & XFS_DIFLAG_SYNC) &&
789 xfs_inherit_sync)
790 di_flags |= XFS_DIFLAG_SYNC;
791 if ((pip->i_d.di_flags & XFS_DIFLAG_NOSYMLINKS) &&
792 xfs_inherit_nosymlinks)
793 di_flags |= XFS_DIFLAG_NOSYMLINKS;
794 if ((pip->i_d.di_flags & XFS_DIFLAG_NODEFRAG) &&
795 xfs_inherit_nodefrag)
796 di_flags |= XFS_DIFLAG_NODEFRAG;
797 if (pip->i_d.di_flags & XFS_DIFLAG_FILESTREAM)
798 di_flags |= XFS_DIFLAG_FILESTREAM;
799 ip->i_d.di_flags |= di_flags;
800 }
801 /* FALLTHROUGH */
802 case S_IFLNK:
803 ip->i_d.di_format = XFS_DINODE_FMT_EXTENTS;
804 ip->i_df.if_flags = XFS_IFEXTENTS;
805 ip->i_df.if_bytes = ip->i_df.if_real_bytes = 0;
806 ip->i_df.if_u1.if_extents = NULL;
807 break;
808 default:
809 ASSERT(0);
810 }
811 /*
812 * Attribute fork settings for new inode.
813 */
814 ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;
815 ip->i_d.di_anextents = 0;
816
817 /*
818 * Log the new values stuffed into the inode.
819 */
820 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
821 xfs_trans_log_inode(tp, ip, flags);
822
823 /* now that we have an i_mode we can setup inode ops and unlock */
824 xfs_setup_inode(ip);
825
826 *ipp = ip;
827 return 0;
828 }
829
830 /*
831 * Allocates a new inode from disk and return a pointer to the
832 * incore copy. This routine will internally commit the current
833 * transaction and allocate a new one if the Space Manager needed
834 * to do an allocation to replenish the inode free-list.
835 *
836 * This routine is designed to be called from xfs_create and
837 * xfs_create_dir.
838 *
839 */
840 int
xfs_dir_ialloc(xfs_trans_t ** tpp,xfs_inode_t * dp,umode_t mode,xfs_nlink_t nlink,xfs_dev_t rdev,prid_t prid,int okalloc,xfs_inode_t ** ipp,int * committed)841 xfs_dir_ialloc(
842 xfs_trans_t **tpp, /* input: current transaction;
843 output: may be a new transaction. */
844 xfs_inode_t *dp, /* directory within whose allocate
845 the inode. */
846 umode_t mode,
847 xfs_nlink_t nlink,
848 xfs_dev_t rdev,
849 prid_t prid, /* project id */
850 int okalloc, /* ok to allocate new space */
851 xfs_inode_t **ipp, /* pointer to inode; it will be
852 locked. */
853 int *committed)
854
855 {
856 xfs_trans_t *tp;
857 xfs_trans_t *ntp;
858 xfs_inode_t *ip;
859 xfs_buf_t *ialloc_context = NULL;
860 int code;
861 void *dqinfo;
862 uint tflags;
863
864 tp = *tpp;
865 ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
866
867 /*
868 * xfs_ialloc will return a pointer to an incore inode if
869 * the Space Manager has an available inode on the free
870 * list. Otherwise, it will do an allocation and replenish
871 * the freelist. Since we can only do one allocation per
872 * transaction without deadlocks, we will need to commit the
873 * current transaction and start a new one. We will then
874 * need to call xfs_ialloc again to get the inode.
875 *
876 * If xfs_ialloc did an allocation to replenish the freelist,
877 * it returns the bp containing the head of the freelist as
878 * ialloc_context. We will hold a lock on it across the
879 * transaction commit so that no other process can steal
880 * the inode(s) that we've just allocated.
881 */
882 code = xfs_ialloc(tp, dp, mode, nlink, rdev, prid, okalloc,
883 &ialloc_context, &ip);
884
885 /*
886 * Return an error if we were unable to allocate a new inode.
887 * This should only happen if we run out of space on disk or
888 * encounter a disk error.
889 */
890 if (code) {
891 *ipp = NULL;
892 return code;
893 }
894 if (!ialloc_context && !ip) {
895 *ipp = NULL;
896 return -ENOSPC;
897 }
898
899 /*
900 * If the AGI buffer is non-NULL, then we were unable to get an
901 * inode in one operation. We need to commit the current
902 * transaction and call xfs_ialloc() again. It is guaranteed
903 * to succeed the second time.
904 */
905 if (ialloc_context) {
906 struct xfs_trans_res tres;
907
908 /*
909 * Normally, xfs_trans_commit releases all the locks.
910 * We call bhold to hang on to the ialloc_context across
911 * the commit. Holding this buffer prevents any other
912 * processes from doing any allocations in this
913 * allocation group.
914 */
915 xfs_trans_bhold(tp, ialloc_context);
916 /*
917 * Save the log reservation so we can use
918 * them in the next transaction.
919 */
920 tres.tr_logres = xfs_trans_get_log_res(tp);
921 tres.tr_logcount = xfs_trans_get_log_count(tp);
922
923 /*
924 * We want the quota changes to be associated with the next
925 * transaction, NOT this one. So, detach the dqinfo from this
926 * and attach it to the next transaction.
927 */
928 dqinfo = NULL;
929 tflags = 0;
930 if (tp->t_dqinfo) {
931 dqinfo = (void *)tp->t_dqinfo;
932 tp->t_dqinfo = NULL;
933 tflags = tp->t_flags & XFS_TRANS_DQ_DIRTY;
934 tp->t_flags &= ~(XFS_TRANS_DQ_DIRTY);
935 }
936
937 ntp = xfs_trans_dup(tp);
938 code = xfs_trans_commit(tp, 0);
939 tp = ntp;
940 if (committed != NULL) {
941 *committed = 1;
942 }
943 /*
944 * If we get an error during the commit processing,
945 * release the buffer that is still held and return
946 * to the caller.
947 */
948 if (code) {
949 xfs_buf_relse(ialloc_context);
950 if (dqinfo) {
951 tp->t_dqinfo = dqinfo;
952 xfs_trans_free_dqinfo(tp);
953 }
954 *tpp = ntp;
955 *ipp = NULL;
956 return code;
957 }
958
959 /*
960 * transaction commit worked ok so we can drop the extra ticket
961 * reference that we gained in xfs_trans_dup()
962 */
963 xfs_log_ticket_put(tp->t_ticket);
964 tres.tr_logflags = XFS_TRANS_PERM_LOG_RES;
965 code = xfs_trans_reserve(tp, &tres, 0, 0);
966
967 /*
968 * Re-attach the quota info that we detached from prev trx.
969 */
970 if (dqinfo) {
971 tp->t_dqinfo = dqinfo;
972 tp->t_flags |= tflags;
973 }
974
975 if (code) {
976 xfs_buf_relse(ialloc_context);
977 *tpp = ntp;
978 *ipp = NULL;
979 return code;
980 }
981 xfs_trans_bjoin(tp, ialloc_context);
982
983 /*
984 * Call ialloc again. Since we've locked out all
985 * other allocations in this allocation group,
986 * this call should always succeed.
987 */
988 code = xfs_ialloc(tp, dp, mode, nlink, rdev, prid,
989 okalloc, &ialloc_context, &ip);
990
991 /*
992 * If we get an error at this point, return to the caller
993 * so that the current transaction can be aborted.
994 */
995 if (code) {
996 *tpp = tp;
997 *ipp = NULL;
998 return code;
999 }
1000 ASSERT(!ialloc_context && ip);
1001
1002 } else {
1003 if (committed != NULL)
1004 *committed = 0;
1005 }
1006
1007 *ipp = ip;
1008 *tpp = tp;
1009
1010 return 0;
1011 }
1012
1013 /*
1014 * Decrement the link count on an inode & log the change.
1015 * If this causes the link count to go to zero, initiate the
1016 * logging activity required to truncate a file.
1017 */
1018 int /* error */
xfs_droplink(xfs_trans_t * tp,xfs_inode_t * ip)1019 xfs_droplink(
1020 xfs_trans_t *tp,
1021 xfs_inode_t *ip)
1022 {
1023 int error;
1024
1025 xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
1026
1027 ASSERT (ip->i_d.di_nlink > 0);
1028 ip->i_d.di_nlink--;
1029 drop_nlink(VFS_I(ip));
1030 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1031
1032 error = 0;
1033 if (ip->i_d.di_nlink == 0) {
1034 /*
1035 * We're dropping the last link to this file.
1036 * Move the on-disk inode to the AGI unlinked list.
1037 * From xfs_inactive() we will pull the inode from
1038 * the list and free it.
1039 */
1040 error = xfs_iunlink(tp, ip);
1041 }
1042 return error;
1043 }
1044
1045 /*
1046 * Increment the link count on an inode & log the change.
1047 */
1048 int
xfs_bumplink(xfs_trans_t * tp,xfs_inode_t * ip)1049 xfs_bumplink(
1050 xfs_trans_t *tp,
1051 xfs_inode_t *ip)
1052 {
1053 xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
1054
1055 ASSERT(ip->i_d.di_version > 1);
1056 ASSERT(ip->i_d.di_nlink > 0 || (VFS_I(ip)->i_state & I_LINKABLE));
1057 ip->i_d.di_nlink++;
1058 inc_nlink(VFS_I(ip));
1059 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1060 return 0;
1061 }
1062
1063 int
xfs_create(xfs_inode_t * dp,struct xfs_name * name,umode_t mode,xfs_dev_t rdev,xfs_inode_t ** ipp)1064 xfs_create(
1065 xfs_inode_t *dp,
1066 struct xfs_name *name,
1067 umode_t mode,
1068 xfs_dev_t rdev,
1069 xfs_inode_t **ipp)
1070 {
1071 int is_dir = S_ISDIR(mode);
1072 struct xfs_mount *mp = dp->i_mount;
1073 struct xfs_inode *ip = NULL;
1074 struct xfs_trans *tp = NULL;
1075 int error;
1076 xfs_bmap_free_t free_list;
1077 xfs_fsblock_t first_block;
1078 bool unlock_dp_on_error = false;
1079 uint cancel_flags;
1080 int committed;
1081 prid_t prid;
1082 struct xfs_dquot *udqp = NULL;
1083 struct xfs_dquot *gdqp = NULL;
1084 struct xfs_dquot *pdqp = NULL;
1085 struct xfs_trans_res tres;
1086 uint resblks;
1087
1088 trace_xfs_create(dp, name);
1089
1090 if (XFS_FORCED_SHUTDOWN(mp))
1091 return -EIO;
1092
1093 prid = xfs_get_initial_prid(dp);
1094
1095 /*
1096 * Make sure that we have allocated dquot(s) on disk.
1097 */
1098 error = xfs_qm_vop_dqalloc(dp, xfs_kuid_to_uid(current_fsuid()),
1099 xfs_kgid_to_gid(current_fsgid()), prid,
1100 XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
1101 &udqp, &gdqp, &pdqp);
1102 if (error)
1103 return error;
1104
1105 if (is_dir) {
1106 rdev = 0;
1107 resblks = XFS_MKDIR_SPACE_RES(mp, name->len);
1108 tres.tr_logres = M_RES(mp)->tr_mkdir.tr_logres;
1109 tres.tr_logcount = XFS_MKDIR_LOG_COUNT;
1110 tp = xfs_trans_alloc(mp, XFS_TRANS_MKDIR);
1111 } else {
1112 resblks = XFS_CREATE_SPACE_RES(mp, name->len);
1113 tres.tr_logres = M_RES(mp)->tr_create.tr_logres;
1114 tres.tr_logcount = XFS_CREATE_LOG_COUNT;
1115 tp = xfs_trans_alloc(mp, XFS_TRANS_CREATE);
1116 }
1117
1118 cancel_flags = XFS_TRANS_RELEASE_LOG_RES;
1119
1120 /*
1121 * Initially assume that the file does not exist and
1122 * reserve the resources for that case. If that is not
1123 * the case we'll drop the one we have and get a more
1124 * appropriate transaction later.
1125 */
1126 tres.tr_logflags = XFS_TRANS_PERM_LOG_RES;
1127 error = xfs_trans_reserve(tp, &tres, resblks, 0);
1128 if (error == -ENOSPC) {
1129 /* flush outstanding delalloc blocks and retry */
1130 xfs_flush_inodes(mp);
1131 error = xfs_trans_reserve(tp, &tres, resblks, 0);
1132 }
1133 if (error == -ENOSPC) {
1134 /* No space at all so try a "no-allocation" reservation */
1135 resblks = 0;
1136 error = xfs_trans_reserve(tp, &tres, 0, 0);
1137 }
1138 if (error) {
1139 cancel_flags = 0;
1140 goto out_trans_cancel;
1141 }
1142
1143 xfs_ilock(dp, XFS_ILOCK_EXCL | XFS_ILOCK_PARENT);
1144 unlock_dp_on_error = true;
1145
1146 xfs_bmap_init(&free_list, &first_block);
1147
1148 /*
1149 * Reserve disk quota and the inode.
1150 */
1151 error = xfs_trans_reserve_quota(tp, mp, udqp, gdqp,
1152 pdqp, resblks, 1, 0);
1153 if (error)
1154 goto out_trans_cancel;
1155
1156 if (!resblks) {
1157 error = xfs_dir_canenter(tp, dp, name);
1158 if (error)
1159 goto out_trans_cancel;
1160 }
1161
1162 /*
1163 * A newly created regular or special file just has one directory
1164 * entry pointing to them, but a directory also the "." entry
1165 * pointing to itself.
1166 */
1167 error = xfs_dir_ialloc(&tp, dp, mode, is_dir ? 2 : 1, rdev,
1168 prid, resblks > 0, &ip, &committed);
1169 if (error) {
1170 if (error == -ENOSPC)
1171 goto out_trans_cancel;
1172 goto out_trans_abort;
1173 }
1174
1175 /*
1176 * Now we join the directory inode to the transaction. We do not do it
1177 * earlier because xfs_dir_ialloc might commit the previous transaction
1178 * (and release all the locks). An error from here on will result in
1179 * the transaction cancel unlocking dp so don't do it explicitly in the
1180 * error path.
1181 */
1182 xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
1183 unlock_dp_on_error = false;
1184
1185 error = xfs_dir_createname(tp, dp, name, ip->i_ino,
1186 &first_block, &free_list, resblks ?
1187 resblks - XFS_IALLOC_SPACE_RES(mp) : 0);
1188 if (error) {
1189 ASSERT(error != -ENOSPC);
1190 goto out_trans_abort;
1191 }
1192 xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1193 xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
1194
1195 if (is_dir) {
1196 error = xfs_dir_init(tp, ip, dp);
1197 if (error)
1198 goto out_bmap_cancel;
1199
1200 error = xfs_bumplink(tp, dp);
1201 if (error)
1202 goto out_bmap_cancel;
1203 }
1204
1205 /*
1206 * If this is a synchronous mount, make sure that the
1207 * create transaction goes to disk before returning to
1208 * the user.
1209 */
1210 if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
1211 xfs_trans_set_sync(tp);
1212
1213 /*
1214 * Attach the dquot(s) to the inodes and modify them incore.
1215 * These ids of the inode couldn't have changed since the new
1216 * inode has been locked ever since it was created.
1217 */
1218 xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp, pdqp);
1219
1220 error = xfs_bmap_finish(&tp, &free_list, &committed);
1221 if (error)
1222 goto out_bmap_cancel;
1223
1224 error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
1225 if (error)
1226 goto out_release_inode;
1227
1228 xfs_qm_dqrele(udqp);
1229 xfs_qm_dqrele(gdqp);
1230 xfs_qm_dqrele(pdqp);
1231
1232 *ipp = ip;
1233 return 0;
1234
1235 out_bmap_cancel:
1236 xfs_bmap_cancel(&free_list);
1237 out_trans_abort:
1238 cancel_flags |= XFS_TRANS_ABORT;
1239 out_trans_cancel:
1240 xfs_trans_cancel(tp, cancel_flags);
1241 out_release_inode:
1242 /*
1243 * Wait until after the current transaction is aborted to
1244 * release the inode. This prevents recursive transactions
1245 * and deadlocks from xfs_inactive.
1246 */
1247 if (ip)
1248 IRELE(ip);
1249
1250 xfs_qm_dqrele(udqp);
1251 xfs_qm_dqrele(gdqp);
1252 xfs_qm_dqrele(pdqp);
1253
1254 if (unlock_dp_on_error)
1255 xfs_iunlock(dp, XFS_ILOCK_EXCL);
1256 return error;
1257 }
1258
1259 int
xfs_create_tmpfile(struct xfs_inode * dp,struct dentry * dentry,umode_t mode,struct xfs_inode ** ipp)1260 xfs_create_tmpfile(
1261 struct xfs_inode *dp,
1262 struct dentry *dentry,
1263 umode_t mode,
1264 struct xfs_inode **ipp)
1265 {
1266 struct xfs_mount *mp = dp->i_mount;
1267 struct xfs_inode *ip = NULL;
1268 struct xfs_trans *tp = NULL;
1269 int error;
1270 uint cancel_flags = XFS_TRANS_RELEASE_LOG_RES;
1271 prid_t prid;
1272 struct xfs_dquot *udqp = NULL;
1273 struct xfs_dquot *gdqp = NULL;
1274 struct xfs_dquot *pdqp = NULL;
1275 struct xfs_trans_res *tres;
1276 uint resblks;
1277
1278 if (XFS_FORCED_SHUTDOWN(mp))
1279 return -EIO;
1280
1281 prid = xfs_get_initial_prid(dp);
1282
1283 /*
1284 * Make sure that we have allocated dquot(s) on disk.
1285 */
1286 error = xfs_qm_vop_dqalloc(dp, xfs_kuid_to_uid(current_fsuid()),
1287 xfs_kgid_to_gid(current_fsgid()), prid,
1288 XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
1289 &udqp, &gdqp, &pdqp);
1290 if (error)
1291 return error;
1292
1293 resblks = XFS_IALLOC_SPACE_RES(mp);
1294 tp = xfs_trans_alloc(mp, XFS_TRANS_CREATE_TMPFILE);
1295
1296 tres = &M_RES(mp)->tr_create_tmpfile;
1297 error = xfs_trans_reserve(tp, tres, resblks, 0);
1298 if (error == -ENOSPC) {
1299 /* No space at all so try a "no-allocation" reservation */
1300 resblks = 0;
1301 error = xfs_trans_reserve(tp, tres, 0, 0);
1302 }
1303 if (error) {
1304 cancel_flags = 0;
1305 goto out_trans_cancel;
1306 }
1307
1308 error = xfs_trans_reserve_quota(tp, mp, udqp, gdqp,
1309 pdqp, resblks, 1, 0);
1310 if (error)
1311 goto out_trans_cancel;
1312
1313 error = xfs_dir_ialloc(&tp, dp, mode, 1, 0,
1314 prid, resblks > 0, &ip, NULL);
1315 if (error) {
1316 if (error == -ENOSPC)
1317 goto out_trans_cancel;
1318 goto out_trans_abort;
1319 }
1320
1321 if (mp->m_flags & XFS_MOUNT_WSYNC)
1322 xfs_trans_set_sync(tp);
1323
1324 /*
1325 * Attach the dquot(s) to the inodes and modify them incore.
1326 * These ids of the inode couldn't have changed since the new
1327 * inode has been locked ever since it was created.
1328 */
1329 xfs_qm_vop_create_dqattach(tp, ip, udqp, gdqp, pdqp);
1330
1331 ip->i_d.di_nlink--;
1332 error = xfs_iunlink(tp, ip);
1333 if (error)
1334 goto out_trans_abort;
1335
1336 error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
1337 if (error)
1338 goto out_release_inode;
1339
1340 xfs_qm_dqrele(udqp);
1341 xfs_qm_dqrele(gdqp);
1342 xfs_qm_dqrele(pdqp);
1343
1344 *ipp = ip;
1345 return 0;
1346
1347 out_trans_abort:
1348 cancel_flags |= XFS_TRANS_ABORT;
1349 out_trans_cancel:
1350 xfs_trans_cancel(tp, cancel_flags);
1351 out_release_inode:
1352 /*
1353 * Wait until after the current transaction is aborted to
1354 * release the inode. This prevents recursive transactions
1355 * and deadlocks from xfs_inactive.
1356 */
1357 if (ip)
1358 IRELE(ip);
1359
1360 xfs_qm_dqrele(udqp);
1361 xfs_qm_dqrele(gdqp);
1362 xfs_qm_dqrele(pdqp);
1363
1364 return error;
1365 }
1366
1367 int
xfs_link(xfs_inode_t * tdp,xfs_inode_t * sip,struct xfs_name * target_name)1368 xfs_link(
1369 xfs_inode_t *tdp,
1370 xfs_inode_t *sip,
1371 struct xfs_name *target_name)
1372 {
1373 xfs_mount_t *mp = tdp->i_mount;
1374 xfs_trans_t *tp;
1375 int error;
1376 xfs_bmap_free_t free_list;
1377 xfs_fsblock_t first_block;
1378 int cancel_flags;
1379 int committed;
1380 int resblks;
1381
1382 trace_xfs_link(tdp, target_name);
1383
1384 ASSERT(!S_ISDIR(sip->i_d.di_mode));
1385
1386 if (XFS_FORCED_SHUTDOWN(mp))
1387 return -EIO;
1388
1389 error = xfs_qm_dqattach(sip, 0);
1390 if (error)
1391 goto std_return;
1392
1393 error = xfs_qm_dqattach(tdp, 0);
1394 if (error)
1395 goto std_return;
1396
1397 tp = xfs_trans_alloc(mp, XFS_TRANS_LINK);
1398 cancel_flags = XFS_TRANS_RELEASE_LOG_RES;
1399 resblks = XFS_LINK_SPACE_RES(mp, target_name->len);
1400 error = xfs_trans_reserve(tp, &M_RES(mp)->tr_link, resblks, 0);
1401 if (error == -ENOSPC) {
1402 resblks = 0;
1403 error = xfs_trans_reserve(tp, &M_RES(mp)->tr_link, 0, 0);
1404 }
1405 if (error) {
1406 cancel_flags = 0;
1407 goto error_return;
1408 }
1409
1410 xfs_lock_two_inodes(sip, tdp, XFS_ILOCK_EXCL);
1411
1412 xfs_trans_ijoin(tp, sip, XFS_ILOCK_EXCL);
1413 xfs_trans_ijoin(tp, tdp, XFS_ILOCK_EXCL);
1414
1415 /*
1416 * If we are using project inheritance, we only allow hard link
1417 * creation in our tree when the project IDs are the same; else
1418 * the tree quota mechanism could be circumvented.
1419 */
1420 if (unlikely((tdp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) &&
1421 (xfs_get_projid(tdp) != xfs_get_projid(sip)))) {
1422 error = -EXDEV;
1423 goto error_return;
1424 }
1425
1426 if (!resblks) {
1427 error = xfs_dir_canenter(tp, tdp, target_name);
1428 if (error)
1429 goto error_return;
1430 }
1431
1432 xfs_bmap_init(&free_list, &first_block);
1433
1434 if (sip->i_d.di_nlink == 0) {
1435 error = xfs_iunlink_remove(tp, sip);
1436 if (error)
1437 goto abort_return;
1438 }
1439
1440 error = xfs_dir_createname(tp, tdp, target_name, sip->i_ino,
1441 &first_block, &free_list, resblks);
1442 if (error)
1443 goto abort_return;
1444 xfs_trans_ichgtime(tp, tdp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
1445 xfs_trans_log_inode(tp, tdp, XFS_ILOG_CORE);
1446
1447 error = xfs_bumplink(tp, sip);
1448 if (error)
1449 goto abort_return;
1450
1451 /*
1452 * If this is a synchronous mount, make sure that the
1453 * link transaction goes to disk before returning to
1454 * the user.
1455 */
1456 if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC)) {
1457 xfs_trans_set_sync(tp);
1458 }
1459
1460 error = xfs_bmap_finish (&tp, &free_list, &committed);
1461 if (error) {
1462 xfs_bmap_cancel(&free_list);
1463 goto abort_return;
1464 }
1465
1466 return xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
1467
1468 abort_return:
1469 cancel_flags |= XFS_TRANS_ABORT;
1470 error_return:
1471 xfs_trans_cancel(tp, cancel_flags);
1472 std_return:
1473 return error;
1474 }
1475
1476 /*
1477 * Free up the underlying blocks past new_size. The new size must be smaller
1478 * than the current size. This routine can be used both for the attribute and
1479 * data fork, and does not modify the inode size, which is left to the caller.
1480 *
1481 * The transaction passed to this routine must have made a permanent log
1482 * reservation of at least XFS_ITRUNCATE_LOG_RES. This routine may commit the
1483 * given transaction and start new ones, so make sure everything involved in
1484 * the transaction is tidy before calling here. Some transaction will be
1485 * returned to the caller to be committed. The incoming transaction must
1486 * already include the inode, and both inode locks must be held exclusively.
1487 * The inode must also be "held" within the transaction. On return the inode
1488 * will be "held" within the returned transaction. This routine does NOT
1489 * require any disk space to be reserved for it within the transaction.
1490 *
1491 * If we get an error, we must return with the inode locked and linked into the
1492 * current transaction. This keeps things simple for the higher level code,
1493 * because it always knows that the inode is locked and held in the transaction
1494 * that returns to it whether errors occur or not. We don't mark the inode
1495 * dirty on error so that transactions can be easily aborted if possible.
1496 */
1497 int
xfs_itruncate_extents(struct xfs_trans ** tpp,struct xfs_inode * ip,int whichfork,xfs_fsize_t new_size)1498 xfs_itruncate_extents(
1499 struct xfs_trans **tpp,
1500 struct xfs_inode *ip,
1501 int whichfork,
1502 xfs_fsize_t new_size)
1503 {
1504 struct xfs_mount *mp = ip->i_mount;
1505 struct xfs_trans *tp = *tpp;
1506 struct xfs_trans *ntp;
1507 xfs_bmap_free_t free_list;
1508 xfs_fsblock_t first_block;
1509 xfs_fileoff_t first_unmap_block;
1510 xfs_fileoff_t last_block;
1511 xfs_filblks_t unmap_len;
1512 int committed;
1513 int error = 0;
1514 int done = 0;
1515
1516 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
1517 ASSERT(!atomic_read(&VFS_I(ip)->i_count) ||
1518 xfs_isilocked(ip, XFS_IOLOCK_EXCL));
1519 ASSERT(new_size <= XFS_ISIZE(ip));
1520 ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
1521 ASSERT(ip->i_itemp != NULL);
1522 ASSERT(ip->i_itemp->ili_lock_flags == 0);
1523 ASSERT(!XFS_NOT_DQATTACHED(mp, ip));
1524
1525 trace_xfs_itruncate_extents_start(ip, new_size);
1526
1527 /*
1528 * Since it is possible for space to become allocated beyond
1529 * the end of the file (in a crash where the space is allocated
1530 * but the inode size is not yet updated), simply remove any
1531 * blocks which show up between the new EOF and the maximum
1532 * possible file size. If the first block to be removed is
1533 * beyond the maximum file size (ie it is the same as last_block),
1534 * then there is nothing to do.
1535 */
1536 first_unmap_block = XFS_B_TO_FSB(mp, (xfs_ufsize_t)new_size);
1537 last_block = XFS_B_TO_FSB(mp, mp->m_super->s_maxbytes);
1538 if (first_unmap_block == last_block)
1539 return 0;
1540
1541 ASSERT(first_unmap_block < last_block);
1542 unmap_len = last_block - first_unmap_block + 1;
1543 while (!done) {
1544 xfs_bmap_init(&free_list, &first_block);
1545 error = xfs_bunmapi(tp, ip,
1546 first_unmap_block, unmap_len,
1547 xfs_bmapi_aflag(whichfork),
1548 XFS_ITRUNC_MAX_EXTENTS,
1549 &first_block, &free_list,
1550 &done);
1551 if (error)
1552 goto out_bmap_cancel;
1553
1554 /*
1555 * Duplicate the transaction that has the permanent
1556 * reservation and commit the old transaction.
1557 */
1558 error = xfs_bmap_finish(&tp, &free_list, &committed);
1559 if (committed)
1560 xfs_trans_ijoin(tp, ip, 0);
1561 if (error)
1562 goto out_bmap_cancel;
1563
1564 if (committed) {
1565 /*
1566 * Mark the inode dirty so it will be logged and
1567 * moved forward in the log as part of every commit.
1568 */
1569 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1570 }
1571
1572 ntp = xfs_trans_dup(tp);
1573 error = xfs_trans_commit(tp, 0);
1574 tp = ntp;
1575
1576 xfs_trans_ijoin(tp, ip, 0);
1577
1578 if (error)
1579 goto out;
1580
1581 /*
1582 * Transaction commit worked ok so we can drop the extra ticket
1583 * reference that we gained in xfs_trans_dup()
1584 */
1585 xfs_log_ticket_put(tp->t_ticket);
1586 error = xfs_trans_reserve(tp, &M_RES(mp)->tr_itruncate, 0, 0);
1587 if (error)
1588 goto out;
1589 }
1590
1591 /*
1592 * Always re-log the inode so that our permanent transaction can keep
1593 * on rolling it forward in the log.
1594 */
1595 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1596
1597 trace_xfs_itruncate_extents_end(ip, new_size);
1598
1599 out:
1600 *tpp = tp;
1601 return error;
1602 out_bmap_cancel:
1603 /*
1604 * If the bunmapi call encounters an error, return to the caller where
1605 * the transaction can be properly aborted. We just need to make sure
1606 * we're not holding any resources that we were not when we came in.
1607 */
1608 xfs_bmap_cancel(&free_list);
1609 goto out;
1610 }
1611
1612 int
xfs_release(xfs_inode_t * ip)1613 xfs_release(
1614 xfs_inode_t *ip)
1615 {
1616 xfs_mount_t *mp = ip->i_mount;
1617 int error;
1618
1619 if (!S_ISREG(ip->i_d.di_mode) || (ip->i_d.di_mode == 0))
1620 return 0;
1621
1622 /* If this is a read-only mount, don't do this (would generate I/O) */
1623 if (mp->m_flags & XFS_MOUNT_RDONLY)
1624 return 0;
1625
1626 if (!XFS_FORCED_SHUTDOWN(mp)) {
1627 int truncated;
1628
1629 /*
1630 * If we previously truncated this file and removed old data
1631 * in the process, we want to initiate "early" writeout on
1632 * the last close. This is an attempt to combat the notorious
1633 * NULL files problem which is particularly noticeable from a
1634 * truncate down, buffered (re-)write (delalloc), followed by
1635 * a crash. What we are effectively doing here is
1636 * significantly reducing the time window where we'd otherwise
1637 * be exposed to that problem.
1638 */
1639 truncated = xfs_iflags_test_and_clear(ip, XFS_ITRUNCATED);
1640 if (truncated) {
1641 xfs_iflags_clear(ip, XFS_IDIRTY_RELEASE);
1642 if (ip->i_delayed_blks > 0) {
1643 error = filemap_flush(VFS_I(ip)->i_mapping);
1644 if (error)
1645 return error;
1646 }
1647 }
1648 }
1649
1650 if (ip->i_d.di_nlink == 0)
1651 return 0;
1652
1653 if (xfs_can_free_eofblocks(ip, false)) {
1654
1655 /*
1656 * If we can't get the iolock just skip truncating the blocks
1657 * past EOF because we could deadlock with the mmap_sem
1658 * otherwise. We'll get another chance to drop them once the
1659 * last reference to the inode is dropped, so we'll never leak
1660 * blocks permanently.
1661 *
1662 * Further, check if the inode is being opened, written and
1663 * closed frequently and we have delayed allocation blocks
1664 * outstanding (e.g. streaming writes from the NFS server),
1665 * truncating the blocks past EOF will cause fragmentation to
1666 * occur.
1667 *
1668 * In this case don't do the truncation, either, but we have to
1669 * be careful how we detect this case. Blocks beyond EOF show
1670 * up as i_delayed_blks even when the inode is clean, so we
1671 * need to truncate them away first before checking for a dirty
1672 * release. Hence on the first dirty close we will still remove
1673 * the speculative allocation, but after that we will leave it
1674 * in place.
1675 */
1676 if (xfs_iflags_test(ip, XFS_IDIRTY_RELEASE))
1677 return 0;
1678
1679 error = xfs_free_eofblocks(mp, ip, true);
1680 if (error && error != -EAGAIN)
1681 return error;
1682
1683 /* delalloc blocks after truncation means it really is dirty */
1684 if (ip->i_delayed_blks)
1685 xfs_iflags_set(ip, XFS_IDIRTY_RELEASE);
1686 }
1687 return 0;
1688 }
1689
1690 /*
1691 * xfs_inactive_truncate
1692 *
1693 * Called to perform a truncate when an inode becomes unlinked.
1694 */
1695 STATIC int
xfs_inactive_truncate(struct xfs_inode * ip)1696 xfs_inactive_truncate(
1697 struct xfs_inode *ip)
1698 {
1699 struct xfs_mount *mp = ip->i_mount;
1700 struct xfs_trans *tp;
1701 int error;
1702
1703 tp = xfs_trans_alloc(mp, XFS_TRANS_INACTIVE);
1704 error = xfs_trans_reserve(tp, &M_RES(mp)->tr_itruncate, 0, 0);
1705 if (error) {
1706 ASSERT(XFS_FORCED_SHUTDOWN(mp));
1707 xfs_trans_cancel(tp, 0);
1708 return error;
1709 }
1710
1711 xfs_ilock(ip, XFS_ILOCK_EXCL);
1712 xfs_trans_ijoin(tp, ip, 0);
1713
1714 /*
1715 * Log the inode size first to prevent stale data exposure in the event
1716 * of a system crash before the truncate completes. See the related
1717 * comment in xfs_setattr_size() for details.
1718 */
1719 ip->i_d.di_size = 0;
1720 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1721
1722 error = xfs_itruncate_extents(&tp, ip, XFS_DATA_FORK, 0);
1723 if (error)
1724 goto error_trans_cancel;
1725
1726 ASSERT(ip->i_d.di_nextents == 0);
1727
1728 error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
1729 if (error)
1730 goto error_unlock;
1731
1732 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1733 return 0;
1734
1735 error_trans_cancel:
1736 xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES | XFS_TRANS_ABORT);
1737 error_unlock:
1738 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1739 return error;
1740 }
1741
1742 /*
1743 * xfs_inactive_ifree()
1744 *
1745 * Perform the inode free when an inode is unlinked.
1746 */
1747 STATIC int
xfs_inactive_ifree(struct xfs_inode * ip)1748 xfs_inactive_ifree(
1749 struct xfs_inode *ip)
1750 {
1751 xfs_bmap_free_t free_list;
1752 xfs_fsblock_t first_block;
1753 int committed;
1754 struct xfs_mount *mp = ip->i_mount;
1755 struct xfs_trans *tp;
1756 int error;
1757
1758 tp = xfs_trans_alloc(mp, XFS_TRANS_INACTIVE);
1759
1760 /*
1761 * The ifree transaction might need to allocate blocks for record
1762 * insertion to the finobt. We don't want to fail here at ENOSPC, so
1763 * allow ifree to dip into the reserved block pool if necessary.
1764 *
1765 * Freeing large sets of inodes generally means freeing inode chunks,
1766 * directory and file data blocks, so this should be relatively safe.
1767 * Only under severe circumstances should it be possible to free enough
1768 * inodes to exhaust the reserve block pool via finobt expansion while
1769 * at the same time not creating free space in the filesystem.
1770 *
1771 * Send a warning if the reservation does happen to fail, as the inode
1772 * now remains allocated and sits on the unlinked list until the fs is
1773 * repaired.
1774 */
1775 tp->t_flags |= XFS_TRANS_RESERVE;
1776 error = xfs_trans_reserve(tp, &M_RES(mp)->tr_ifree,
1777 XFS_IFREE_SPACE_RES(mp), 0);
1778 if (error) {
1779 if (error == -ENOSPC) {
1780 xfs_warn_ratelimited(mp,
1781 "Failed to remove inode(s) from unlinked list. "
1782 "Please free space, unmount and run xfs_repair.");
1783 } else {
1784 ASSERT(XFS_FORCED_SHUTDOWN(mp));
1785 }
1786 xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES);
1787 return error;
1788 }
1789
1790 xfs_ilock(ip, XFS_ILOCK_EXCL);
1791 xfs_trans_ijoin(tp, ip, 0);
1792
1793 xfs_bmap_init(&free_list, &first_block);
1794 error = xfs_ifree(tp, ip, &free_list);
1795 if (error) {
1796 /*
1797 * If we fail to free the inode, shut down. The cancel
1798 * might do that, we need to make sure. Otherwise the
1799 * inode might be lost for a long time or forever.
1800 */
1801 if (!XFS_FORCED_SHUTDOWN(mp)) {
1802 xfs_notice(mp, "%s: xfs_ifree returned error %d",
1803 __func__, error);
1804 xfs_force_shutdown(mp, SHUTDOWN_META_IO_ERROR);
1805 }
1806 xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES|XFS_TRANS_ABORT);
1807 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1808 return error;
1809 }
1810
1811 /*
1812 * Credit the quota account(s). The inode is gone.
1813 */
1814 xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_ICOUNT, -1);
1815
1816 /*
1817 * Just ignore errors at this point. There is nothing we can
1818 * do except to try to keep going. Make sure it's not a silent
1819 * error.
1820 */
1821 error = xfs_bmap_finish(&tp, &free_list, &committed);
1822 if (error)
1823 xfs_notice(mp, "%s: xfs_bmap_finish returned error %d",
1824 __func__, error);
1825 error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
1826 if (error)
1827 xfs_notice(mp, "%s: xfs_trans_commit returned error %d",
1828 __func__, error);
1829
1830 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1831 return 0;
1832 }
1833
1834 /*
1835 * xfs_inactive
1836 *
1837 * This is called when the vnode reference count for the vnode
1838 * goes to zero. If the file has been unlinked, then it must
1839 * now be truncated. Also, we clear all of the read-ahead state
1840 * kept for the inode here since the file is now closed.
1841 */
1842 void
xfs_inactive(xfs_inode_t * ip)1843 xfs_inactive(
1844 xfs_inode_t *ip)
1845 {
1846 struct xfs_mount *mp;
1847 int error;
1848 int truncate = 0;
1849
1850 /*
1851 * If the inode is already free, then there can be nothing
1852 * to clean up here.
1853 */
1854 if (ip->i_d.di_mode == 0) {
1855 ASSERT(ip->i_df.if_real_bytes == 0);
1856 ASSERT(ip->i_df.if_broot_bytes == 0);
1857 return;
1858 }
1859
1860 mp = ip->i_mount;
1861
1862 /* If this is a read-only mount, don't do this (would generate I/O) */
1863 if (mp->m_flags & XFS_MOUNT_RDONLY)
1864 return;
1865
1866 if (ip->i_d.di_nlink != 0) {
1867 /*
1868 * force is true because we are evicting an inode from the
1869 * cache. Post-eof blocks must be freed, lest we end up with
1870 * broken free space accounting.
1871 */
1872 if (xfs_can_free_eofblocks(ip, true))
1873 xfs_free_eofblocks(mp, ip, false);
1874
1875 return;
1876 }
1877
1878 if (S_ISREG(ip->i_d.di_mode) &&
1879 (ip->i_d.di_size != 0 || XFS_ISIZE(ip) != 0 ||
1880 ip->i_d.di_nextents > 0 || ip->i_delayed_blks > 0))
1881 truncate = 1;
1882
1883 error = xfs_qm_dqattach(ip, 0);
1884 if (error)
1885 return;
1886
1887 if (S_ISLNK(ip->i_d.di_mode))
1888 error = xfs_inactive_symlink(ip);
1889 else if (truncate)
1890 error = xfs_inactive_truncate(ip);
1891 if (error)
1892 return;
1893
1894 /*
1895 * If there are attributes associated with the file then blow them away
1896 * now. The code calls a routine that recursively deconstructs the
1897 * attribute fork. If also blows away the in-core attribute fork.
1898 */
1899 if (XFS_IFORK_Q(ip)) {
1900 error = xfs_attr_inactive(ip);
1901 if (error)
1902 return;
1903 }
1904
1905 ASSERT(!ip->i_afp);
1906 ASSERT(ip->i_d.di_anextents == 0);
1907 ASSERT(ip->i_d.di_forkoff == 0);
1908
1909 /*
1910 * Free the inode.
1911 */
1912 error = xfs_inactive_ifree(ip);
1913 if (error)
1914 return;
1915
1916 /*
1917 * Release the dquots held by inode, if any.
1918 */
1919 xfs_qm_dqdetach(ip);
1920 }
1921
1922 /*
1923 * This is called when the inode's link count goes to 0.
1924 * We place the on-disk inode on a list in the AGI. It
1925 * will be pulled from this list when the inode is freed.
1926 */
1927 int
xfs_iunlink(xfs_trans_t * tp,xfs_inode_t * ip)1928 xfs_iunlink(
1929 xfs_trans_t *tp,
1930 xfs_inode_t *ip)
1931 {
1932 xfs_mount_t *mp;
1933 xfs_agi_t *agi;
1934 xfs_dinode_t *dip;
1935 xfs_buf_t *agibp;
1936 xfs_buf_t *ibp;
1937 xfs_agino_t agino;
1938 short bucket_index;
1939 int offset;
1940 int error;
1941
1942 ASSERT(ip->i_d.di_nlink == 0);
1943 ASSERT(ip->i_d.di_mode != 0);
1944
1945 mp = tp->t_mountp;
1946
1947 /*
1948 * Get the agi buffer first. It ensures lock ordering
1949 * on the list.
1950 */
1951 error = xfs_read_agi(mp, tp, XFS_INO_TO_AGNO(mp, ip->i_ino), &agibp);
1952 if (error)
1953 return error;
1954 agi = XFS_BUF_TO_AGI(agibp);
1955
1956 /*
1957 * Get the index into the agi hash table for the
1958 * list this inode will go on.
1959 */
1960 agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
1961 ASSERT(agino != 0);
1962 bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
1963 ASSERT(agi->agi_unlinked[bucket_index]);
1964 ASSERT(be32_to_cpu(agi->agi_unlinked[bucket_index]) != agino);
1965
1966 if (agi->agi_unlinked[bucket_index] != cpu_to_be32(NULLAGINO)) {
1967 /*
1968 * There is already another inode in the bucket we need
1969 * to add ourselves to. Add us at the front of the list.
1970 * Here we put the head pointer into our next pointer,
1971 * and then we fall through to point the head at us.
1972 */
1973 error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &ibp,
1974 0, 0);
1975 if (error)
1976 return error;
1977
1978 ASSERT(dip->di_next_unlinked == cpu_to_be32(NULLAGINO));
1979 dip->di_next_unlinked = agi->agi_unlinked[bucket_index];
1980 offset = ip->i_imap.im_boffset +
1981 offsetof(xfs_dinode_t, di_next_unlinked);
1982
1983 /* need to recalc the inode CRC if appropriate */
1984 xfs_dinode_calc_crc(mp, dip);
1985
1986 xfs_trans_inode_buf(tp, ibp);
1987 xfs_trans_log_buf(tp, ibp, offset,
1988 (offset + sizeof(xfs_agino_t) - 1));
1989 xfs_inobp_check(mp, ibp);
1990 }
1991
1992 /*
1993 * Point the bucket head pointer at the inode being inserted.
1994 */
1995 ASSERT(agino != 0);
1996 agi->agi_unlinked[bucket_index] = cpu_to_be32(agino);
1997 offset = offsetof(xfs_agi_t, agi_unlinked) +
1998 (sizeof(xfs_agino_t) * bucket_index);
1999 xfs_trans_buf_set_type(tp, agibp, XFS_BLFT_AGI_BUF);
2000 xfs_trans_log_buf(tp, agibp, offset,
2001 (offset + sizeof(xfs_agino_t) - 1));
2002 return 0;
2003 }
2004
2005 /*
2006 * Pull the on-disk inode from the AGI unlinked list.
2007 */
2008 STATIC int
xfs_iunlink_remove(xfs_trans_t * tp,xfs_inode_t * ip)2009 xfs_iunlink_remove(
2010 xfs_trans_t *tp,
2011 xfs_inode_t *ip)
2012 {
2013 xfs_ino_t next_ino;
2014 xfs_mount_t *mp;
2015 xfs_agi_t *agi;
2016 xfs_dinode_t *dip;
2017 xfs_buf_t *agibp;
2018 xfs_buf_t *ibp;
2019 xfs_agnumber_t agno;
2020 xfs_agino_t agino;
2021 xfs_agino_t next_agino;
2022 xfs_buf_t *last_ibp;
2023 xfs_dinode_t *last_dip = NULL;
2024 short bucket_index;
2025 int offset, last_offset = 0;
2026 int error;
2027
2028 mp = tp->t_mountp;
2029 agno = XFS_INO_TO_AGNO(mp, ip->i_ino);
2030
2031 /*
2032 * Get the agi buffer first. It ensures lock ordering
2033 * on the list.
2034 */
2035 error = xfs_read_agi(mp, tp, agno, &agibp);
2036 if (error)
2037 return error;
2038
2039 agi = XFS_BUF_TO_AGI(agibp);
2040
2041 /*
2042 * Get the index into the agi hash table for the
2043 * list this inode will go on.
2044 */
2045 agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
2046 ASSERT(agino != 0);
2047 bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
2048 ASSERT(agi->agi_unlinked[bucket_index] != cpu_to_be32(NULLAGINO));
2049 ASSERT(agi->agi_unlinked[bucket_index]);
2050
2051 if (be32_to_cpu(agi->agi_unlinked[bucket_index]) == agino) {
2052 /*
2053 * We're at the head of the list. Get the inode's on-disk
2054 * buffer to see if there is anyone after us on the list.
2055 * Only modify our next pointer if it is not already NULLAGINO.
2056 * This saves us the overhead of dealing with the buffer when
2057 * there is no need to change it.
2058 */
2059 error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &ibp,
2060 0, 0);
2061 if (error) {
2062 xfs_warn(mp, "%s: xfs_imap_to_bp returned error %d.",
2063 __func__, error);
2064 return error;
2065 }
2066 next_agino = be32_to_cpu(dip->di_next_unlinked);
2067 ASSERT(next_agino != 0);
2068 if (next_agino != NULLAGINO) {
2069 dip->di_next_unlinked = cpu_to_be32(NULLAGINO);
2070 offset = ip->i_imap.im_boffset +
2071 offsetof(xfs_dinode_t, di_next_unlinked);
2072
2073 /* need to recalc the inode CRC if appropriate */
2074 xfs_dinode_calc_crc(mp, dip);
2075
2076 xfs_trans_inode_buf(tp, ibp);
2077 xfs_trans_log_buf(tp, ibp, offset,
2078 (offset + sizeof(xfs_agino_t) - 1));
2079 xfs_inobp_check(mp, ibp);
2080 } else {
2081 xfs_trans_brelse(tp, ibp);
2082 }
2083 /*
2084 * Point the bucket head pointer at the next inode.
2085 */
2086 ASSERT(next_agino != 0);
2087 ASSERT(next_agino != agino);
2088 agi->agi_unlinked[bucket_index] = cpu_to_be32(next_agino);
2089 offset = offsetof(xfs_agi_t, agi_unlinked) +
2090 (sizeof(xfs_agino_t) * bucket_index);
2091 xfs_trans_buf_set_type(tp, agibp, XFS_BLFT_AGI_BUF);
2092 xfs_trans_log_buf(tp, agibp, offset,
2093 (offset + sizeof(xfs_agino_t) - 1));
2094 } else {
2095 /*
2096 * We need to search the list for the inode being freed.
2097 */
2098 next_agino = be32_to_cpu(agi->agi_unlinked[bucket_index]);
2099 last_ibp = NULL;
2100 while (next_agino != agino) {
2101 struct xfs_imap imap;
2102
2103 if (last_ibp)
2104 xfs_trans_brelse(tp, last_ibp);
2105
2106 imap.im_blkno = 0;
2107 next_ino = XFS_AGINO_TO_INO(mp, agno, next_agino);
2108
2109 error = xfs_imap(mp, tp, next_ino, &imap, 0);
2110 if (error) {
2111 xfs_warn(mp,
2112 "%s: xfs_imap returned error %d.",
2113 __func__, error);
2114 return error;
2115 }
2116
2117 error = xfs_imap_to_bp(mp, tp, &imap, &last_dip,
2118 &last_ibp, 0, 0);
2119 if (error) {
2120 xfs_warn(mp,
2121 "%s: xfs_imap_to_bp returned error %d.",
2122 __func__, error);
2123 return error;
2124 }
2125
2126 last_offset = imap.im_boffset;
2127 next_agino = be32_to_cpu(last_dip->di_next_unlinked);
2128 ASSERT(next_agino != NULLAGINO);
2129 ASSERT(next_agino != 0);
2130 }
2131
2132 /*
2133 * Now last_ibp points to the buffer previous to us on the
2134 * unlinked list. Pull us from the list.
2135 */
2136 error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &ibp,
2137 0, 0);
2138 if (error) {
2139 xfs_warn(mp, "%s: xfs_imap_to_bp(2) returned error %d.",
2140 __func__, error);
2141 return error;
2142 }
2143 next_agino = be32_to_cpu(dip->di_next_unlinked);
2144 ASSERT(next_agino != 0);
2145 ASSERT(next_agino != agino);
2146 if (next_agino != NULLAGINO) {
2147 dip->di_next_unlinked = cpu_to_be32(NULLAGINO);
2148 offset = ip->i_imap.im_boffset +
2149 offsetof(xfs_dinode_t, di_next_unlinked);
2150
2151 /* need to recalc the inode CRC if appropriate */
2152 xfs_dinode_calc_crc(mp, dip);
2153
2154 xfs_trans_inode_buf(tp, ibp);
2155 xfs_trans_log_buf(tp, ibp, offset,
2156 (offset + sizeof(xfs_agino_t) - 1));
2157 xfs_inobp_check(mp, ibp);
2158 } else {
2159 xfs_trans_brelse(tp, ibp);
2160 }
2161 /*
2162 * Point the previous inode on the list to the next inode.
2163 */
2164 last_dip->di_next_unlinked = cpu_to_be32(next_agino);
2165 ASSERT(next_agino != 0);
2166 offset = last_offset + offsetof(xfs_dinode_t, di_next_unlinked);
2167
2168 /* need to recalc the inode CRC if appropriate */
2169 xfs_dinode_calc_crc(mp, last_dip);
2170
2171 xfs_trans_inode_buf(tp, last_ibp);
2172 xfs_trans_log_buf(tp, last_ibp, offset,
2173 (offset + sizeof(xfs_agino_t) - 1));
2174 xfs_inobp_check(mp, last_ibp);
2175 }
2176 return 0;
2177 }
2178
2179 /*
2180 * A big issue when freeing the inode cluster is that we _cannot_ skip any
2181 * inodes that are in memory - they all must be marked stale and attached to
2182 * the cluster buffer.
2183 */
2184 STATIC int
xfs_ifree_cluster(xfs_inode_t * free_ip,xfs_trans_t * tp,xfs_ino_t inum)2185 xfs_ifree_cluster(
2186 xfs_inode_t *free_ip,
2187 xfs_trans_t *tp,
2188 xfs_ino_t inum)
2189 {
2190 xfs_mount_t *mp = free_ip->i_mount;
2191 int blks_per_cluster;
2192 int inodes_per_cluster;
2193 int nbufs;
2194 int i, j;
2195 xfs_daddr_t blkno;
2196 xfs_buf_t *bp;
2197 xfs_inode_t *ip;
2198 xfs_inode_log_item_t *iip;
2199 xfs_log_item_t *lip;
2200 struct xfs_perag *pag;
2201
2202 pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, inum));
2203 blks_per_cluster = xfs_icluster_size_fsb(mp);
2204 inodes_per_cluster = blks_per_cluster << mp->m_sb.sb_inopblog;
2205 nbufs = mp->m_ialloc_blks / blks_per_cluster;
2206
2207 for (j = 0; j < nbufs; j++, inum += inodes_per_cluster) {
2208 blkno = XFS_AGB_TO_DADDR(mp, XFS_INO_TO_AGNO(mp, inum),
2209 XFS_INO_TO_AGBNO(mp, inum));
2210
2211 /*
2212 * We obtain and lock the backing buffer first in the process
2213 * here, as we have to ensure that any dirty inode that we
2214 * can't get the flush lock on is attached to the buffer.
2215 * If we scan the in-memory inodes first, then buffer IO can
2216 * complete before we get a lock on it, and hence we may fail
2217 * to mark all the active inodes on the buffer stale.
2218 */
2219 bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, blkno,
2220 mp->m_bsize * blks_per_cluster,
2221 XBF_UNMAPPED);
2222
2223 if (!bp)
2224 return -ENOMEM;
2225
2226 /*
2227 * This buffer may not have been correctly initialised as we
2228 * didn't read it from disk. That's not important because we are
2229 * only using to mark the buffer as stale in the log, and to
2230 * attach stale cached inodes on it. That means it will never be
2231 * dispatched for IO. If it is, we want to know about it, and we
2232 * want it to fail. We can acheive this by adding a write
2233 * verifier to the buffer.
2234 */
2235 bp->b_ops = &xfs_inode_buf_ops;
2236
2237 /*
2238 * Walk the inodes already attached to the buffer and mark them
2239 * stale. These will all have the flush locks held, so an
2240 * in-memory inode walk can't lock them. By marking them all
2241 * stale first, we will not attempt to lock them in the loop
2242 * below as the XFS_ISTALE flag will be set.
2243 */
2244 lip = bp->b_fspriv;
2245 while (lip) {
2246 if (lip->li_type == XFS_LI_INODE) {
2247 iip = (xfs_inode_log_item_t *)lip;
2248 ASSERT(iip->ili_logged == 1);
2249 lip->li_cb = xfs_istale_done;
2250 xfs_trans_ail_copy_lsn(mp->m_ail,
2251 &iip->ili_flush_lsn,
2252 &iip->ili_item.li_lsn);
2253 xfs_iflags_set(iip->ili_inode, XFS_ISTALE);
2254 }
2255 lip = lip->li_bio_list;
2256 }
2257
2258
2259 /*
2260 * For each inode in memory attempt to add it to the inode
2261 * buffer and set it up for being staled on buffer IO
2262 * completion. This is safe as we've locked out tail pushing
2263 * and flushing by locking the buffer.
2264 *
2265 * We have already marked every inode that was part of a
2266 * transaction stale above, which means there is no point in
2267 * even trying to lock them.
2268 */
2269 for (i = 0; i < inodes_per_cluster; i++) {
2270 retry:
2271 rcu_read_lock();
2272 ip = radix_tree_lookup(&pag->pag_ici_root,
2273 XFS_INO_TO_AGINO(mp, (inum + i)));
2274
2275 /* Inode not in memory, nothing to do */
2276 if (!ip) {
2277 rcu_read_unlock();
2278 continue;
2279 }
2280
2281 /*
2282 * because this is an RCU protected lookup, we could
2283 * find a recently freed or even reallocated inode
2284 * during the lookup. We need to check under the
2285 * i_flags_lock for a valid inode here. Skip it if it
2286 * is not valid, the wrong inode or stale.
2287 */
2288 spin_lock(&ip->i_flags_lock);
2289 if (ip->i_ino != inum + i ||
2290 __xfs_iflags_test(ip, XFS_ISTALE)) {
2291 spin_unlock(&ip->i_flags_lock);
2292 rcu_read_unlock();
2293 continue;
2294 }
2295 spin_unlock(&ip->i_flags_lock);
2296
2297 /*
2298 * Don't try to lock/unlock the current inode, but we
2299 * _cannot_ skip the other inodes that we did not find
2300 * in the list attached to the buffer and are not
2301 * already marked stale. If we can't lock it, back off
2302 * and retry.
2303 */
2304 if (ip != free_ip &&
2305 !xfs_ilock_nowait(ip, XFS_ILOCK_EXCL)) {
2306 rcu_read_unlock();
2307 delay(1);
2308 goto retry;
2309 }
2310 rcu_read_unlock();
2311
2312 xfs_iflock(ip);
2313 xfs_iflags_set(ip, XFS_ISTALE);
2314
2315 /*
2316 * we don't need to attach clean inodes or those only
2317 * with unlogged changes (which we throw away, anyway).
2318 */
2319 iip = ip->i_itemp;
2320 if (!iip || xfs_inode_clean(ip)) {
2321 ASSERT(ip != free_ip);
2322 xfs_ifunlock(ip);
2323 xfs_iunlock(ip, XFS_ILOCK_EXCL);
2324 continue;
2325 }
2326
2327 iip->ili_last_fields = iip->ili_fields;
2328 iip->ili_fields = 0;
2329 iip->ili_logged = 1;
2330 xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn,
2331 &iip->ili_item.li_lsn);
2332
2333 xfs_buf_attach_iodone(bp, xfs_istale_done,
2334 &iip->ili_item);
2335
2336 if (ip != free_ip)
2337 xfs_iunlock(ip, XFS_ILOCK_EXCL);
2338 }
2339
2340 xfs_trans_stale_inode_buf(tp, bp);
2341 xfs_trans_binval(tp, bp);
2342 }
2343
2344 xfs_perag_put(pag);
2345 return 0;
2346 }
2347
2348 /*
2349 * This is called to return an inode to the inode free list.
2350 * The inode should already be truncated to 0 length and have
2351 * no pages associated with it. This routine also assumes that
2352 * the inode is already a part of the transaction.
2353 *
2354 * The on-disk copy of the inode will have been added to the list
2355 * of unlinked inodes in the AGI. We need to remove the inode from
2356 * that list atomically with respect to freeing it here.
2357 */
2358 int
xfs_ifree(xfs_trans_t * tp,xfs_inode_t * ip,xfs_bmap_free_t * flist)2359 xfs_ifree(
2360 xfs_trans_t *tp,
2361 xfs_inode_t *ip,
2362 xfs_bmap_free_t *flist)
2363 {
2364 int error;
2365 int delete;
2366 xfs_ino_t first_ino;
2367
2368 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
2369 ASSERT(ip->i_d.di_nlink == 0);
2370 ASSERT(ip->i_d.di_nextents == 0);
2371 ASSERT(ip->i_d.di_anextents == 0);
2372 ASSERT(ip->i_d.di_size == 0 || !S_ISREG(ip->i_d.di_mode));
2373 ASSERT(ip->i_d.di_nblocks == 0);
2374
2375 /*
2376 * Pull the on-disk inode from the AGI unlinked list.
2377 */
2378 error = xfs_iunlink_remove(tp, ip);
2379 if (error)
2380 return error;
2381
2382 error = xfs_difree(tp, ip->i_ino, flist, &delete, &first_ino);
2383 if (error)
2384 return error;
2385
2386 ip->i_d.di_mode = 0; /* mark incore inode as free */
2387 ip->i_d.di_flags = 0;
2388 ip->i_d.di_dmevmask = 0;
2389 ip->i_d.di_forkoff = 0; /* mark the attr fork not in use */
2390 ip->i_d.di_format = XFS_DINODE_FMT_EXTENTS;
2391 ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;
2392 /*
2393 * Bump the generation count so no one will be confused
2394 * by reincarnations of this inode.
2395 */
2396 ip->i_d.di_gen++;
2397 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
2398
2399 if (delete)
2400 error = xfs_ifree_cluster(ip, tp, first_ino);
2401
2402 return error;
2403 }
2404
2405 /*
2406 * This is called to unpin an inode. The caller must have the inode locked
2407 * in at least shared mode so that the buffer cannot be subsequently pinned
2408 * once someone is waiting for it to be unpinned.
2409 */
2410 static void
xfs_iunpin(struct xfs_inode * ip)2411 xfs_iunpin(
2412 struct xfs_inode *ip)
2413 {
2414 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
2415
2416 trace_xfs_inode_unpin_nowait(ip, _RET_IP_);
2417
2418 /* Give the log a push to start the unpinning I/O */
2419 xfs_log_force_lsn(ip->i_mount, ip->i_itemp->ili_last_lsn, 0);
2420
2421 }
2422
2423 static void
__xfs_iunpin_wait(struct xfs_inode * ip)2424 __xfs_iunpin_wait(
2425 struct xfs_inode *ip)
2426 {
2427 wait_queue_head_t *wq = bit_waitqueue(&ip->i_flags, __XFS_IPINNED_BIT);
2428 DEFINE_WAIT_BIT(wait, &ip->i_flags, __XFS_IPINNED_BIT);
2429
2430 xfs_iunpin(ip);
2431
2432 do {
2433 prepare_to_wait(wq, &wait.wait, TASK_UNINTERRUPTIBLE);
2434 if (xfs_ipincount(ip))
2435 io_schedule();
2436 } while (xfs_ipincount(ip));
2437 finish_wait(wq, &wait.wait);
2438 }
2439
2440 void
xfs_iunpin_wait(struct xfs_inode * ip)2441 xfs_iunpin_wait(
2442 struct xfs_inode *ip)
2443 {
2444 if (xfs_ipincount(ip))
2445 __xfs_iunpin_wait(ip);
2446 }
2447
2448 /*
2449 * Removing an inode from the namespace involves removing the directory entry
2450 * and dropping the link count on the inode. Removing the directory entry can
2451 * result in locking an AGF (directory blocks were freed) and removing a link
2452 * count can result in placing the inode on an unlinked list which results in
2453 * locking an AGI.
2454 *
2455 * The big problem here is that we have an ordering constraint on AGF and AGI
2456 * locking - inode allocation locks the AGI, then can allocate a new extent for
2457 * new inodes, locking the AGF after the AGI. Similarly, freeing the inode
2458 * removes the inode from the unlinked list, requiring that we lock the AGI
2459 * first, and then freeing the inode can result in an inode chunk being freed
2460 * and hence freeing disk space requiring that we lock an AGF.
2461 *
2462 * Hence the ordering that is imposed by other parts of the code is AGI before
2463 * AGF. This means we cannot remove the directory entry before we drop the inode
2464 * reference count and put it on the unlinked list as this results in a lock
2465 * order of AGF then AGI, and this can deadlock against inode allocation and
2466 * freeing. Therefore we must drop the link counts before we remove the
2467 * directory entry.
2468 *
2469 * This is still safe from a transactional point of view - it is not until we
2470 * get to xfs_bmap_finish() that we have the possibility of multiple
2471 * transactions in this operation. Hence as long as we remove the directory
2472 * entry and drop the link count in the first transaction of the remove
2473 * operation, there are no transactional constraints on the ordering here.
2474 */
2475 int
xfs_remove(xfs_inode_t * dp,struct xfs_name * name,xfs_inode_t * ip)2476 xfs_remove(
2477 xfs_inode_t *dp,
2478 struct xfs_name *name,
2479 xfs_inode_t *ip)
2480 {
2481 xfs_mount_t *mp = dp->i_mount;
2482 xfs_trans_t *tp = NULL;
2483 int is_dir = S_ISDIR(ip->i_d.di_mode);
2484 int error = 0;
2485 xfs_bmap_free_t free_list;
2486 xfs_fsblock_t first_block;
2487 int cancel_flags;
2488 int committed;
2489 int link_zero;
2490 uint resblks;
2491 uint log_count;
2492
2493 trace_xfs_remove(dp, name);
2494
2495 if (XFS_FORCED_SHUTDOWN(mp))
2496 return -EIO;
2497
2498 error = xfs_qm_dqattach(dp, 0);
2499 if (error)
2500 goto std_return;
2501
2502 error = xfs_qm_dqattach(ip, 0);
2503 if (error)
2504 goto std_return;
2505
2506 if (is_dir) {
2507 tp = xfs_trans_alloc(mp, XFS_TRANS_RMDIR);
2508 log_count = XFS_DEFAULT_LOG_COUNT;
2509 } else {
2510 tp = xfs_trans_alloc(mp, XFS_TRANS_REMOVE);
2511 log_count = XFS_REMOVE_LOG_COUNT;
2512 }
2513 cancel_flags = XFS_TRANS_RELEASE_LOG_RES;
2514
2515 /*
2516 * We try to get the real space reservation first,
2517 * allowing for directory btree deletion(s) implying
2518 * possible bmap insert(s). If we can't get the space
2519 * reservation then we use 0 instead, and avoid the bmap
2520 * btree insert(s) in the directory code by, if the bmap
2521 * insert tries to happen, instead trimming the LAST
2522 * block from the directory.
2523 */
2524 resblks = XFS_REMOVE_SPACE_RES(mp);
2525 error = xfs_trans_reserve(tp, &M_RES(mp)->tr_remove, resblks, 0);
2526 if (error == -ENOSPC) {
2527 resblks = 0;
2528 error = xfs_trans_reserve(tp, &M_RES(mp)->tr_remove, 0, 0);
2529 }
2530 if (error) {
2531 ASSERT(error != -ENOSPC);
2532 cancel_flags = 0;
2533 goto out_trans_cancel;
2534 }
2535
2536 xfs_lock_two_inodes(dp, ip, XFS_ILOCK_EXCL);
2537
2538 xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
2539 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
2540
2541 /*
2542 * If we're removing a directory perform some additional validation.
2543 */
2544 cancel_flags |= XFS_TRANS_ABORT;
2545 if (is_dir) {
2546 ASSERT(ip->i_d.di_nlink >= 2);
2547 if (ip->i_d.di_nlink != 2) {
2548 error = -ENOTEMPTY;
2549 goto out_trans_cancel;
2550 }
2551 if (!xfs_dir_isempty(ip)) {
2552 error = -ENOTEMPTY;
2553 goto out_trans_cancel;
2554 }
2555
2556 /* Drop the link from ip's "..". */
2557 error = xfs_droplink(tp, dp);
2558 if (error)
2559 goto out_trans_cancel;
2560
2561 /* Drop the "." link from ip to self. */
2562 error = xfs_droplink(tp, ip);
2563 if (error)
2564 goto out_trans_cancel;
2565 } else {
2566 /*
2567 * When removing a non-directory we need to log the parent
2568 * inode here. For a directory this is done implicitly
2569 * by the xfs_droplink call for the ".." entry.
2570 */
2571 xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
2572 }
2573 xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2574
2575 /* Drop the link from dp to ip. */
2576 error = xfs_droplink(tp, ip);
2577 if (error)
2578 goto out_trans_cancel;
2579
2580 /* Determine if this is the last link while the inode is locked */
2581 link_zero = (ip->i_d.di_nlink == 0);
2582
2583 xfs_bmap_init(&free_list, &first_block);
2584 error = xfs_dir_removename(tp, dp, name, ip->i_ino,
2585 &first_block, &free_list, resblks);
2586 if (error) {
2587 ASSERT(error != -ENOENT);
2588 goto out_bmap_cancel;
2589 }
2590
2591 /*
2592 * If this is a synchronous mount, make sure that the
2593 * remove transaction goes to disk before returning to
2594 * the user.
2595 */
2596 if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC))
2597 xfs_trans_set_sync(tp);
2598
2599 error = xfs_bmap_finish(&tp, &free_list, &committed);
2600 if (error)
2601 goto out_bmap_cancel;
2602
2603 error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
2604 if (error)
2605 goto std_return;
2606
2607 if (is_dir && xfs_inode_is_filestream(ip))
2608 xfs_filestream_deassociate(ip);
2609
2610 return 0;
2611
2612 out_bmap_cancel:
2613 xfs_bmap_cancel(&free_list);
2614 out_trans_cancel:
2615 xfs_trans_cancel(tp, cancel_flags);
2616 std_return:
2617 return error;
2618 }
2619
2620 /*
2621 * Enter all inodes for a rename transaction into a sorted array.
2622 */
2623 STATIC void
xfs_sort_for_rename(xfs_inode_t * dp1,xfs_inode_t * dp2,xfs_inode_t * ip1,xfs_inode_t * ip2,xfs_inode_t ** i_tab,int * num_inodes)2624 xfs_sort_for_rename(
2625 xfs_inode_t *dp1, /* in: old (source) directory inode */
2626 xfs_inode_t *dp2, /* in: new (target) directory inode */
2627 xfs_inode_t *ip1, /* in: inode of old entry */
2628 xfs_inode_t *ip2, /* in: inode of new entry, if it
2629 already exists, NULL otherwise. */
2630 xfs_inode_t **i_tab,/* out: array of inode returned, sorted */
2631 int *num_inodes) /* out: number of inodes in array */
2632 {
2633 xfs_inode_t *temp;
2634 int i, j;
2635
2636 /*
2637 * i_tab contains a list of pointers to inodes. We initialize
2638 * the table here & we'll sort it. We will then use it to
2639 * order the acquisition of the inode locks.
2640 *
2641 * Note that the table may contain duplicates. e.g., dp1 == dp2.
2642 */
2643 i_tab[0] = dp1;
2644 i_tab[1] = dp2;
2645 i_tab[2] = ip1;
2646 if (ip2) {
2647 *num_inodes = 4;
2648 i_tab[3] = ip2;
2649 } else {
2650 *num_inodes = 3;
2651 i_tab[3] = NULL;
2652 }
2653
2654 /*
2655 * Sort the elements via bubble sort. (Remember, there are at
2656 * most 4 elements to sort, so this is adequate.)
2657 */
2658 for (i = 0; i < *num_inodes; i++) {
2659 for (j = 1; j < *num_inodes; j++) {
2660 if (i_tab[j]->i_ino < i_tab[j-1]->i_ino) {
2661 temp = i_tab[j];
2662 i_tab[j] = i_tab[j-1];
2663 i_tab[j-1] = temp;
2664 }
2665 }
2666 }
2667 }
2668
2669 /*
2670 * xfs_rename
2671 */
2672 int
xfs_rename(xfs_inode_t * src_dp,struct xfs_name * src_name,xfs_inode_t * src_ip,xfs_inode_t * target_dp,struct xfs_name * target_name,xfs_inode_t * target_ip)2673 xfs_rename(
2674 xfs_inode_t *src_dp,
2675 struct xfs_name *src_name,
2676 xfs_inode_t *src_ip,
2677 xfs_inode_t *target_dp,
2678 struct xfs_name *target_name,
2679 xfs_inode_t *target_ip)
2680 {
2681 xfs_trans_t *tp = NULL;
2682 xfs_mount_t *mp = src_dp->i_mount;
2683 int new_parent; /* moving to a new dir */
2684 int src_is_directory; /* src_name is a directory */
2685 int error;
2686 xfs_bmap_free_t free_list;
2687 xfs_fsblock_t first_block;
2688 int cancel_flags;
2689 int committed;
2690 xfs_inode_t *inodes[4];
2691 int spaceres;
2692 int num_inodes;
2693
2694 trace_xfs_rename(src_dp, target_dp, src_name, target_name);
2695
2696 new_parent = (src_dp != target_dp);
2697 src_is_directory = S_ISDIR(src_ip->i_d.di_mode);
2698
2699 xfs_sort_for_rename(src_dp, target_dp, src_ip, target_ip,
2700 inodes, &num_inodes);
2701
2702 xfs_bmap_init(&free_list, &first_block);
2703 tp = xfs_trans_alloc(mp, XFS_TRANS_RENAME);
2704 cancel_flags = XFS_TRANS_RELEASE_LOG_RES;
2705 spaceres = XFS_RENAME_SPACE_RES(mp, target_name->len);
2706 error = xfs_trans_reserve(tp, &M_RES(mp)->tr_rename, spaceres, 0);
2707 if (error == -ENOSPC) {
2708 spaceres = 0;
2709 error = xfs_trans_reserve(tp, &M_RES(mp)->tr_rename, 0, 0);
2710 }
2711 if (error) {
2712 xfs_trans_cancel(tp, 0);
2713 goto std_return;
2714 }
2715
2716 /*
2717 * Attach the dquots to the inodes
2718 */
2719 error = xfs_qm_vop_rename_dqattach(inodes);
2720 if (error) {
2721 xfs_trans_cancel(tp, cancel_flags);
2722 goto std_return;
2723 }
2724
2725 /*
2726 * Lock all the participating inodes. Depending upon whether
2727 * the target_name exists in the target directory, and
2728 * whether the target directory is the same as the source
2729 * directory, we can lock from 2 to 4 inodes.
2730 */
2731 xfs_lock_inodes(inodes, num_inodes, XFS_ILOCK_EXCL);
2732
2733 /*
2734 * Join all the inodes to the transaction. From this point on,
2735 * we can rely on either trans_commit or trans_cancel to unlock
2736 * them.
2737 */
2738 xfs_trans_ijoin(tp, src_dp, XFS_ILOCK_EXCL);
2739 if (new_parent)
2740 xfs_trans_ijoin(tp, target_dp, XFS_ILOCK_EXCL);
2741 xfs_trans_ijoin(tp, src_ip, XFS_ILOCK_EXCL);
2742 if (target_ip)
2743 xfs_trans_ijoin(tp, target_ip, XFS_ILOCK_EXCL);
2744
2745 /*
2746 * If we are using project inheritance, we only allow renames
2747 * into our tree when the project IDs are the same; else the
2748 * tree quota mechanism would be circumvented.
2749 */
2750 if (unlikely((target_dp->i_d.di_flags & XFS_DIFLAG_PROJINHERIT) &&
2751 (xfs_get_projid(target_dp) != xfs_get_projid(src_ip)))) {
2752 error = -EXDEV;
2753 goto error_return;
2754 }
2755
2756 /*
2757 * Set up the target.
2758 */
2759 if (target_ip == NULL) {
2760 /*
2761 * If there's no space reservation, check the entry will
2762 * fit before actually inserting it.
2763 */
2764 if (!spaceres) {
2765 error = xfs_dir_canenter(tp, target_dp, target_name);
2766 if (error)
2767 goto error_return;
2768 }
2769 /*
2770 * If target does not exist and the rename crosses
2771 * directories, adjust the target directory link count
2772 * to account for the ".." reference from the new entry.
2773 */
2774 error = xfs_dir_createname(tp, target_dp, target_name,
2775 src_ip->i_ino, &first_block,
2776 &free_list, spaceres);
2777 if (error == -ENOSPC)
2778 goto error_return;
2779 if (error)
2780 goto abort_return;
2781
2782 xfs_trans_ichgtime(tp, target_dp,
2783 XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2784
2785 if (new_parent && src_is_directory) {
2786 error = xfs_bumplink(tp, target_dp);
2787 if (error)
2788 goto abort_return;
2789 }
2790 } else { /* target_ip != NULL */
2791 /*
2792 * If target exists and it's a directory, check that both
2793 * target and source are directories and that target can be
2794 * destroyed, or that neither is a directory.
2795 */
2796 if (S_ISDIR(target_ip->i_d.di_mode)) {
2797 /*
2798 * Make sure target dir is empty.
2799 */
2800 if (!(xfs_dir_isempty(target_ip)) ||
2801 (target_ip->i_d.di_nlink > 2)) {
2802 error = -EEXIST;
2803 goto error_return;
2804 }
2805 }
2806
2807 /*
2808 * Link the source inode under the target name.
2809 * If the source inode is a directory and we are moving
2810 * it across directories, its ".." entry will be
2811 * inconsistent until we replace that down below.
2812 *
2813 * In case there is already an entry with the same
2814 * name at the destination directory, remove it first.
2815 */
2816 error = xfs_dir_replace(tp, target_dp, target_name,
2817 src_ip->i_ino,
2818 &first_block, &free_list, spaceres);
2819 if (error)
2820 goto abort_return;
2821
2822 xfs_trans_ichgtime(tp, target_dp,
2823 XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2824
2825 /*
2826 * Decrement the link count on the target since the target
2827 * dir no longer points to it.
2828 */
2829 error = xfs_droplink(tp, target_ip);
2830 if (error)
2831 goto abort_return;
2832
2833 if (src_is_directory) {
2834 /*
2835 * Drop the link from the old "." entry.
2836 */
2837 error = xfs_droplink(tp, target_ip);
2838 if (error)
2839 goto abort_return;
2840 }
2841 } /* target_ip != NULL */
2842
2843 /*
2844 * Remove the source.
2845 */
2846 if (new_parent && src_is_directory) {
2847 /*
2848 * Rewrite the ".." entry to point to the new
2849 * directory.
2850 */
2851 error = xfs_dir_replace(tp, src_ip, &xfs_name_dotdot,
2852 target_dp->i_ino,
2853 &first_block, &free_list, spaceres);
2854 ASSERT(error != -EEXIST);
2855 if (error)
2856 goto abort_return;
2857 }
2858
2859 /*
2860 * We always want to hit the ctime on the source inode.
2861 *
2862 * This isn't strictly required by the standards since the source
2863 * inode isn't really being changed, but old unix file systems did
2864 * it and some incremental backup programs won't work without it.
2865 */
2866 xfs_trans_ichgtime(tp, src_ip, XFS_ICHGTIME_CHG);
2867 xfs_trans_log_inode(tp, src_ip, XFS_ILOG_CORE);
2868
2869 /*
2870 * Adjust the link count on src_dp. This is necessary when
2871 * renaming a directory, either within one parent when
2872 * the target existed, or across two parent directories.
2873 */
2874 if (src_is_directory && (new_parent || target_ip != NULL)) {
2875
2876 /*
2877 * Decrement link count on src_directory since the
2878 * entry that's moved no longer points to it.
2879 */
2880 error = xfs_droplink(tp, src_dp);
2881 if (error)
2882 goto abort_return;
2883 }
2884
2885 error = xfs_dir_removename(tp, src_dp, src_name, src_ip->i_ino,
2886 &first_block, &free_list, spaceres);
2887 if (error)
2888 goto abort_return;
2889
2890 xfs_trans_ichgtime(tp, src_dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
2891 xfs_trans_log_inode(tp, src_dp, XFS_ILOG_CORE);
2892 if (new_parent)
2893 xfs_trans_log_inode(tp, target_dp, XFS_ILOG_CORE);
2894
2895 /*
2896 * If this is a synchronous mount, make sure that the
2897 * rename transaction goes to disk before returning to
2898 * the user.
2899 */
2900 if (mp->m_flags & (XFS_MOUNT_WSYNC|XFS_MOUNT_DIRSYNC)) {
2901 xfs_trans_set_sync(tp);
2902 }
2903
2904 error = xfs_bmap_finish(&tp, &free_list, &committed);
2905 if (error) {
2906 xfs_bmap_cancel(&free_list);
2907 xfs_trans_cancel(tp, (XFS_TRANS_RELEASE_LOG_RES |
2908 XFS_TRANS_ABORT));
2909 goto std_return;
2910 }
2911
2912 /*
2913 * trans_commit will unlock src_ip, target_ip & decrement
2914 * the vnode references.
2915 */
2916 return xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
2917
2918 abort_return:
2919 cancel_flags |= XFS_TRANS_ABORT;
2920 error_return:
2921 xfs_bmap_cancel(&free_list);
2922 xfs_trans_cancel(tp, cancel_flags);
2923 std_return:
2924 return error;
2925 }
2926
2927 STATIC int
xfs_iflush_cluster(xfs_inode_t * ip,xfs_buf_t * bp)2928 xfs_iflush_cluster(
2929 xfs_inode_t *ip,
2930 xfs_buf_t *bp)
2931 {
2932 xfs_mount_t *mp = ip->i_mount;
2933 struct xfs_perag *pag;
2934 unsigned long first_index, mask;
2935 unsigned long inodes_per_cluster;
2936 int ilist_size;
2937 xfs_inode_t **ilist;
2938 xfs_inode_t *iq;
2939 int nr_found;
2940 int clcount = 0;
2941 int bufwasdelwri;
2942 int i;
2943
2944 pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));
2945
2946 inodes_per_cluster = mp->m_inode_cluster_size >> mp->m_sb.sb_inodelog;
2947 ilist_size = inodes_per_cluster * sizeof(xfs_inode_t *);
2948 ilist = kmem_alloc(ilist_size, KM_MAYFAIL|KM_NOFS);
2949 if (!ilist)
2950 goto out_put;
2951
2952 mask = ~(((mp->m_inode_cluster_size >> mp->m_sb.sb_inodelog)) - 1);
2953 first_index = XFS_INO_TO_AGINO(mp, ip->i_ino) & mask;
2954 rcu_read_lock();
2955 /* really need a gang lookup range call here */
2956 nr_found = radix_tree_gang_lookup(&pag->pag_ici_root, (void**)ilist,
2957 first_index, inodes_per_cluster);
2958 if (nr_found == 0)
2959 goto out_free;
2960
2961 for (i = 0; i < nr_found; i++) {
2962 iq = ilist[i];
2963 if (iq == ip)
2964 continue;
2965
2966 /*
2967 * because this is an RCU protected lookup, we could find a
2968 * recently freed or even reallocated inode during the lookup.
2969 * We need to check under the i_flags_lock for a valid inode
2970 * here. Skip it if it is not valid or the wrong inode.
2971 */
2972 spin_lock(&iq->i_flags_lock);
2973 if (!iq->i_ino ||
2974 __xfs_iflags_test(iq, XFS_ISTALE) ||
2975 (XFS_INO_TO_AGINO(mp, iq->i_ino) & mask) != first_index) {
2976 spin_unlock(&iq->i_flags_lock);
2977 continue;
2978 }
2979 spin_unlock(&iq->i_flags_lock);
2980
2981 /*
2982 * Do an un-protected check to see if the inode is dirty and
2983 * is a candidate for flushing. These checks will be repeated
2984 * later after the appropriate locks are acquired.
2985 */
2986 if (xfs_inode_clean(iq) && xfs_ipincount(iq) == 0)
2987 continue;
2988
2989 /*
2990 * Try to get locks. If any are unavailable or it is pinned,
2991 * then this inode cannot be flushed and is skipped.
2992 */
2993
2994 if (!xfs_ilock_nowait(iq, XFS_ILOCK_SHARED))
2995 continue;
2996 if (!xfs_iflock_nowait(iq)) {
2997 xfs_iunlock(iq, XFS_ILOCK_SHARED);
2998 continue;
2999 }
3000 if (xfs_ipincount(iq)) {
3001 xfs_ifunlock(iq);
3002 xfs_iunlock(iq, XFS_ILOCK_SHARED);
3003 continue;
3004 }
3005
3006 /*
3007 * arriving here means that this inode can be flushed. First
3008 * re-check that it's dirty before flushing.
3009 */
3010 if (!xfs_inode_clean(iq)) {
3011 int error;
3012 error = xfs_iflush_int(iq, bp);
3013 if (error) {
3014 xfs_iunlock(iq, XFS_ILOCK_SHARED);
3015 goto cluster_corrupt_out;
3016 }
3017 clcount++;
3018 } else {
3019 xfs_ifunlock(iq);
3020 }
3021 xfs_iunlock(iq, XFS_ILOCK_SHARED);
3022 }
3023
3024 if (clcount) {
3025 XFS_STATS_INC(xs_icluster_flushcnt);
3026 XFS_STATS_ADD(xs_icluster_flushinode, clcount);
3027 }
3028
3029 out_free:
3030 rcu_read_unlock();
3031 kmem_free(ilist);
3032 out_put:
3033 xfs_perag_put(pag);
3034 return 0;
3035
3036
3037 cluster_corrupt_out:
3038 /*
3039 * Corruption detected in the clustering loop. Invalidate the
3040 * inode buffer and shut down the filesystem.
3041 */
3042 rcu_read_unlock();
3043 /*
3044 * Clean up the buffer. If it was delwri, just release it --
3045 * brelse can handle it with no problems. If not, shut down the
3046 * filesystem before releasing the buffer.
3047 */
3048 bufwasdelwri = (bp->b_flags & _XBF_DELWRI_Q);
3049 if (bufwasdelwri)
3050 xfs_buf_relse(bp);
3051
3052 xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
3053
3054 if (!bufwasdelwri) {
3055 /*
3056 * Just like incore_relse: if we have b_iodone functions,
3057 * mark the buffer as an error and call them. Otherwise
3058 * mark it as stale and brelse.
3059 */
3060 if (bp->b_iodone) {
3061 XFS_BUF_UNDONE(bp);
3062 xfs_buf_stale(bp);
3063 xfs_buf_ioerror(bp, -EIO);
3064 xfs_buf_ioend(bp);
3065 } else {
3066 xfs_buf_stale(bp);
3067 xfs_buf_relse(bp);
3068 }
3069 }
3070
3071 /*
3072 * Unlocks the flush lock
3073 */
3074 xfs_iflush_abort(iq, false);
3075 kmem_free(ilist);
3076 xfs_perag_put(pag);
3077 return -EFSCORRUPTED;
3078 }
3079
3080 /*
3081 * Flush dirty inode metadata into the backing buffer.
3082 *
3083 * The caller must have the inode lock and the inode flush lock held. The
3084 * inode lock will still be held upon return to the caller, and the inode
3085 * flush lock will be released after the inode has reached the disk.
3086 *
3087 * The caller must write out the buffer returned in *bpp and release it.
3088 */
3089 int
xfs_iflush(struct xfs_inode * ip,struct xfs_buf ** bpp)3090 xfs_iflush(
3091 struct xfs_inode *ip,
3092 struct xfs_buf **bpp)
3093 {
3094 struct xfs_mount *mp = ip->i_mount;
3095 struct xfs_buf *bp = NULL;
3096 struct xfs_dinode *dip;
3097 int error;
3098
3099 XFS_STATS_INC(xs_iflush_count);
3100
3101 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
3102 ASSERT(xfs_isiflocked(ip));
3103 ASSERT(ip->i_d.di_format != XFS_DINODE_FMT_BTREE ||
3104 ip->i_d.di_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK));
3105
3106 *bpp = NULL;
3107
3108 xfs_iunpin_wait(ip);
3109
3110 /*
3111 * For stale inodes we cannot rely on the backing buffer remaining
3112 * stale in cache for the remaining life of the stale inode and so
3113 * xfs_imap_to_bp() below may give us a buffer that no longer contains
3114 * inodes below. We have to check this after ensuring the inode is
3115 * unpinned so that it is safe to reclaim the stale inode after the
3116 * flush call.
3117 */
3118 if (xfs_iflags_test(ip, XFS_ISTALE)) {
3119 xfs_ifunlock(ip);
3120 return 0;
3121 }
3122
3123 /*
3124 * This may have been unpinned because the filesystem is shutting
3125 * down forcibly. If that's the case we must not write this inode
3126 * to disk, because the log record didn't make it to disk.
3127 *
3128 * We also have to remove the log item from the AIL in this case,
3129 * as we wait for an empty AIL as part of the unmount process.
3130 */
3131 if (XFS_FORCED_SHUTDOWN(mp)) {
3132 error = -EIO;
3133 goto abort_out;
3134 }
3135
3136 /*
3137 * Get the buffer containing the on-disk inode. We are doing a try-lock
3138 * operation here, so we may get an EAGAIN error. In that case, we
3139 * simply want to return with the inode still dirty.
3140 *
3141 * If we get any other error, we effectively have a corruption situation
3142 * and we cannot flush the inode, so we treat it the same as failing
3143 * xfs_iflush_int().
3144 */
3145 error = xfs_imap_to_bp(mp, NULL, &ip->i_imap, &dip, &bp, XBF_TRYLOCK,
3146 0);
3147 if (error == -EAGAIN) {
3148 xfs_ifunlock(ip);
3149 return error;
3150 }
3151 if (error)
3152 goto corrupt_out;
3153
3154 /*
3155 * First flush out the inode that xfs_iflush was called with.
3156 */
3157 error = xfs_iflush_int(ip, bp);
3158 if (error)
3159 goto corrupt_out;
3160
3161 /*
3162 * If the buffer is pinned then push on the log now so we won't
3163 * get stuck waiting in the write for too long.
3164 */
3165 if (xfs_buf_ispinned(bp))
3166 xfs_log_force(mp, 0);
3167
3168 /*
3169 * inode clustering:
3170 * see if other inodes can be gathered into this write
3171 */
3172 error = xfs_iflush_cluster(ip, bp);
3173 if (error)
3174 goto cluster_corrupt_out;
3175
3176 *bpp = bp;
3177 return 0;
3178
3179 corrupt_out:
3180 if (bp)
3181 xfs_buf_relse(bp);
3182 xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
3183 cluster_corrupt_out:
3184 error = -EFSCORRUPTED;
3185 abort_out:
3186 /*
3187 * Unlocks the flush lock
3188 */
3189 xfs_iflush_abort(ip, false);
3190 return error;
3191 }
3192
3193 STATIC int
xfs_iflush_int(struct xfs_inode * ip,struct xfs_buf * bp)3194 xfs_iflush_int(
3195 struct xfs_inode *ip,
3196 struct xfs_buf *bp)
3197 {
3198 struct xfs_inode_log_item *iip = ip->i_itemp;
3199 struct xfs_dinode *dip;
3200 struct xfs_mount *mp = ip->i_mount;
3201
3202 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
3203 ASSERT(xfs_isiflocked(ip));
3204 ASSERT(ip->i_d.di_format != XFS_DINODE_FMT_BTREE ||
3205 ip->i_d.di_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK));
3206 ASSERT(iip != NULL && iip->ili_fields != 0);
3207 ASSERT(ip->i_d.di_version > 1);
3208
3209 /* set *dip = inode's place in the buffer */
3210 dip = (xfs_dinode_t *)xfs_buf_offset(bp, ip->i_imap.im_boffset);
3211
3212 if (XFS_TEST_ERROR(dip->di_magic != cpu_to_be16(XFS_DINODE_MAGIC),
3213 mp, XFS_ERRTAG_IFLUSH_1, XFS_RANDOM_IFLUSH_1)) {
3214 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3215 "%s: Bad inode %Lu magic number 0x%x, ptr 0x%p",
3216 __func__, ip->i_ino, be16_to_cpu(dip->di_magic), dip);
3217 goto corrupt_out;
3218 }
3219 if (XFS_TEST_ERROR(ip->i_d.di_magic != XFS_DINODE_MAGIC,
3220 mp, XFS_ERRTAG_IFLUSH_2, XFS_RANDOM_IFLUSH_2)) {
3221 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3222 "%s: Bad inode %Lu, ptr 0x%p, magic number 0x%x",
3223 __func__, ip->i_ino, ip, ip->i_d.di_magic);
3224 goto corrupt_out;
3225 }
3226 if (S_ISREG(ip->i_d.di_mode)) {
3227 if (XFS_TEST_ERROR(
3228 (ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS) &&
3229 (ip->i_d.di_format != XFS_DINODE_FMT_BTREE),
3230 mp, XFS_ERRTAG_IFLUSH_3, XFS_RANDOM_IFLUSH_3)) {
3231 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3232 "%s: Bad regular inode %Lu, ptr 0x%p",
3233 __func__, ip->i_ino, ip);
3234 goto corrupt_out;
3235 }
3236 } else if (S_ISDIR(ip->i_d.di_mode)) {
3237 if (XFS_TEST_ERROR(
3238 (ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS) &&
3239 (ip->i_d.di_format != XFS_DINODE_FMT_BTREE) &&
3240 (ip->i_d.di_format != XFS_DINODE_FMT_LOCAL),
3241 mp, XFS_ERRTAG_IFLUSH_4, XFS_RANDOM_IFLUSH_4)) {
3242 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3243 "%s: Bad directory inode %Lu, ptr 0x%p",
3244 __func__, ip->i_ino, ip);
3245 goto corrupt_out;
3246 }
3247 }
3248 if (XFS_TEST_ERROR(ip->i_d.di_nextents + ip->i_d.di_anextents >
3249 ip->i_d.di_nblocks, mp, XFS_ERRTAG_IFLUSH_5,
3250 XFS_RANDOM_IFLUSH_5)) {
3251 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3252 "%s: detected corrupt incore inode %Lu, "
3253 "total extents = %d, nblocks = %Ld, ptr 0x%p",
3254 __func__, ip->i_ino,
3255 ip->i_d.di_nextents + ip->i_d.di_anextents,
3256 ip->i_d.di_nblocks, ip);
3257 goto corrupt_out;
3258 }
3259 if (XFS_TEST_ERROR(ip->i_d.di_forkoff > mp->m_sb.sb_inodesize,
3260 mp, XFS_ERRTAG_IFLUSH_6, XFS_RANDOM_IFLUSH_6)) {
3261 xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
3262 "%s: bad inode %Lu, forkoff 0x%x, ptr 0x%p",
3263 __func__, ip->i_ino, ip->i_d.di_forkoff, ip);
3264 goto corrupt_out;
3265 }
3266
3267 /*
3268 * Inode item log recovery for v2 inodes are dependent on the
3269 * di_flushiter count for correct sequencing. We bump the flush
3270 * iteration count so we can detect flushes which postdate a log record
3271 * during recovery. This is redundant as we now log every change and
3272 * hence this can't happen but we need to still do it to ensure
3273 * backwards compatibility with old kernels that predate logging all
3274 * inode changes.
3275 */
3276 if (ip->i_d.di_version < 3)
3277 ip->i_d.di_flushiter++;
3278
3279 /*
3280 * Copy the dirty parts of the inode into the on-disk
3281 * inode. We always copy out the core of the inode,
3282 * because if the inode is dirty at all the core must
3283 * be.
3284 */
3285 xfs_dinode_to_disk(dip, &ip->i_d);
3286
3287 /* Wrap, we never let the log put out DI_MAX_FLUSH */
3288 if (ip->i_d.di_flushiter == DI_MAX_FLUSH)
3289 ip->i_d.di_flushiter = 0;
3290
3291 xfs_iflush_fork(ip, dip, iip, XFS_DATA_FORK);
3292 if (XFS_IFORK_Q(ip))
3293 xfs_iflush_fork(ip, dip, iip, XFS_ATTR_FORK);
3294 xfs_inobp_check(mp, bp);
3295
3296 /*
3297 * We've recorded everything logged in the inode, so we'd like to clear
3298 * the ili_fields bits so we don't log and flush things unnecessarily.
3299 * However, we can't stop logging all this information until the data
3300 * we've copied into the disk buffer is written to disk. If we did we
3301 * might overwrite the copy of the inode in the log with all the data
3302 * after re-logging only part of it, and in the face of a crash we
3303 * wouldn't have all the data we need to recover.
3304 *
3305 * What we do is move the bits to the ili_last_fields field. When
3306 * logging the inode, these bits are moved back to the ili_fields field.
3307 * In the xfs_iflush_done() routine we clear ili_last_fields, since we
3308 * know that the information those bits represent is permanently on
3309 * disk. As long as the flush completes before the inode is logged
3310 * again, then both ili_fields and ili_last_fields will be cleared.
3311 *
3312 * We can play with the ili_fields bits here, because the inode lock
3313 * must be held exclusively in order to set bits there and the flush
3314 * lock protects the ili_last_fields bits. Set ili_logged so the flush
3315 * done routine can tell whether or not to look in the AIL. Also, store
3316 * the current LSN of the inode so that we can tell whether the item has
3317 * moved in the AIL from xfs_iflush_done(). In order to read the lsn we
3318 * need the AIL lock, because it is a 64 bit value that cannot be read
3319 * atomically.
3320 */
3321 iip->ili_last_fields = iip->ili_fields;
3322 iip->ili_fields = 0;
3323 iip->ili_logged = 1;
3324
3325 xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn,
3326 &iip->ili_item.li_lsn);
3327
3328 /*
3329 * Attach the function xfs_iflush_done to the inode's
3330 * buffer. This will remove the inode from the AIL
3331 * and unlock the inode's flush lock when the inode is
3332 * completely written to disk.
3333 */
3334 xfs_buf_attach_iodone(bp, xfs_iflush_done, &iip->ili_item);
3335
3336 /* update the lsn in the on disk inode if required */
3337 if (ip->i_d.di_version == 3)
3338 dip->di_lsn = cpu_to_be64(iip->ili_item.li_lsn);
3339
3340 /* generate the checksum. */
3341 xfs_dinode_calc_crc(mp, dip);
3342
3343 ASSERT(bp->b_fspriv != NULL);
3344 ASSERT(bp->b_iodone != NULL);
3345 return 0;
3346
3347 corrupt_out:
3348 return -EFSCORRUPTED;
3349 }
3350