Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
7b718769 NS |
2 | * Copyright (c) 2000-2005 Silicon Graphics, Inc. |
3 | * All Rights Reserved. | |
1da177e4 | 4 | * |
7b718769 NS |
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 | |
1da177e4 LT |
7 | * published by the Free Software Foundation. |
8 | * | |
7b718769 NS |
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. | |
1da177e4 | 13 | * |
7b718769 NS |
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 | |
1da177e4 | 17 | */ |
1da177e4 | 18 | #include "xfs.h" |
a844f451 | 19 | #include "xfs_fs.h" |
1da177e4 | 20 | #include "xfs_types.h" |
a844f451 | 21 | #include "xfs_bit.h" |
1da177e4 | 22 | #include "xfs_log.h" |
a844f451 | 23 | #include "xfs_inum.h" |
1da177e4 LT |
24 | #include "xfs_trans.h" |
25 | #include "xfs_sb.h" | |
26 | #include "xfs_ag.h" | |
1da177e4 LT |
27 | #include "xfs_dir2.h" |
28 | #include "xfs_dmapi.h" | |
29 | #include "xfs_mount.h" | |
1da177e4 | 30 | #include "xfs_bmap_btree.h" |
a844f451 | 31 | #include "xfs_alloc_btree.h" |
1da177e4 | 32 | #include "xfs_ialloc_btree.h" |
1da177e4 | 33 | #include "xfs_dir2_sf.h" |
a844f451 | 34 | #include "xfs_attr_sf.h" |
1da177e4 LT |
35 | #include "xfs_dinode.h" |
36 | #include "xfs_inode.h" | |
a844f451 NS |
37 | #include "xfs_btree.h" |
38 | #include "xfs_ialloc.h" | |
1da177e4 LT |
39 | #include "xfs_quota.h" |
40 | #include "xfs_utils.h" | |
783a2f65 DC |
41 | #include "xfs_trans_priv.h" |
42 | #include "xfs_inode_item.h" | |
1da177e4 | 43 | |
1da177e4 | 44 | /* |
6441e549 | 45 | * Check the validity of the inode we just found it the cache |
1da177e4 | 46 | */ |
6441e549 DC |
47 | static int |
48 | xfs_iget_cache_hit( | |
6441e549 DC |
49 | struct xfs_perag *pag, |
50 | struct xfs_inode *ip, | |
51 | int flags, | |
52 | int lock_flags) __releases(pag->pag_ici_lock) | |
1da177e4 | 53 | { |
6441e549 | 54 | struct xfs_mount *mp = ip->i_mount; |
6bfb3d06 | 55 | int error = EAGAIN; |
da353b0d | 56 | |
6441e549 DC |
57 | /* |
58 | * If INEW is set this inode is being set up | |
bf904248 | 59 | * If IRECLAIM is set this inode is being torn down |
6441e549 DC |
60 | * Pause and try again. |
61 | */ | |
bf904248 | 62 | if (xfs_iflags_test(ip, (XFS_INEW|XFS_IRECLAIM))) { |
6441e549 DC |
63 | XFS_STATS_INC(xs_ig_frecycle); |
64 | goto out_error; | |
65 | } | |
da353b0d | 66 | |
bf904248 DC |
67 | /* If IRECLAIMABLE is set, we've torn down the vfs inode part */ |
68 | if (xfs_iflags_test(ip, XFS_IRECLAIMABLE)) { | |
69 | ||
da353b0d | 70 | /* |
bf904248 DC |
71 | * If lookup is racing with unlink, then we should return an |
72 | * error immediately so we don't remove it from the reclaim | |
73 | * list and potentially leak the inode. | |
da353b0d | 74 | */ |
bf904248 DC |
75 | if ((ip->i_d.di_mode == 0) && !(flags & XFS_IGET_CREATE)) { |
76 | error = ENOENT; | |
6441e549 DC |
77 | goto out_error; |
78 | } | |
bf904248 DC |
79 | |
80 | xfs_itrace_exit_tag(ip, "xfs_iget.alloc"); | |
da353b0d | 81 | |
6441e549 | 82 | /* |
bf904248 DC |
83 | * We need to re-initialise the VFS inode as it has been |
84 | * 'freed' by the VFS. Do this here so we can deal with | |
85 | * errors cleanly, then tag it so it can be set up correctly | |
86 | * later. | |
6441e549 | 87 | */ |
bf904248 DC |
88 | if (!inode_init_always(mp->m_super, VFS_I(ip))) { |
89 | error = ENOMEM; | |
6441e549 | 90 | goto out_error; |
da353b0d | 91 | } |
6bfb3d06 DC |
92 | |
93 | /* | |
94 | * We must set the XFS_INEW flag before clearing the | |
95 | * XFS_IRECLAIMABLE flag so that if a racing lookup does | |
96 | * not find the XFS_IRECLAIMABLE above but has the igrab() | |
97 | * below succeed we can safely check XFS_INEW to detect | |
98 | * that this inode is still being initialised. | |
99 | */ | |
bf904248 | 100 | xfs_iflags_set(ip, XFS_INEW); |
6441e549 | 101 | xfs_iflags_clear(ip, XFS_IRECLAIMABLE); |
396beb85 DC |
102 | |
103 | /* clear the radix tree reclaim flag as well. */ | |
104 | __xfs_inode_clear_reclaim_tag(mp, pag, ip); | |
bf904248 DC |
105 | } else if (!igrab(VFS_I(ip))) { |
106 | /* If the VFS inode is being torn down, pause and try again. */ | |
bf904248 DC |
107 | XFS_STATS_INC(xs_ig_frecycle); |
108 | goto out_error; | |
6bfb3d06 DC |
109 | } else if (xfs_iflags_test(ip, XFS_INEW)) { |
110 | /* | |
111 | * We are racing with another cache hit that is | |
112 | * currently recycling this inode out of the XFS_IRECLAIMABLE | |
113 | * state. Wait for the initialisation to complete before | |
114 | * continuing. | |
115 | */ | |
116 | wait_on_inode(VFS_I(ip)); | |
6441e549 | 117 | } |
1da177e4 | 118 | |
6441e549 DC |
119 | if (ip->i_d.di_mode == 0 && !(flags & XFS_IGET_CREATE)) { |
120 | error = ENOENT; | |
6bfb3d06 DC |
121 | iput(VFS_I(ip)); |
122 | goto out_error; | |
6441e549 | 123 | } |
da353b0d | 124 | |
6bfb3d06 DC |
125 | /* We've got a live one. */ |
126 | read_unlock(&pag->pag_ici_lock); | |
127 | ||
6441e549 DC |
128 | if (lock_flags != 0) |
129 | xfs_ilock(ip, lock_flags); | |
da353b0d | 130 | |
6441e549 DC |
131 | xfs_iflags_clear(ip, XFS_ISTALE); |
132 | xfs_itrace_exit_tag(ip, "xfs_iget.found"); | |
133 | XFS_STATS_INC(xs_ig_found); | |
134 | return 0; | |
1da177e4 | 135 | |
6441e549 | 136 | out_error: |
da353b0d | 137 | read_unlock(&pag->pag_ici_lock); |
6441e549 DC |
138 | return error; |
139 | } | |
140 | ||
141 | ||
142 | static int | |
143 | xfs_iget_cache_miss( | |
144 | struct xfs_mount *mp, | |
145 | struct xfs_perag *pag, | |
146 | xfs_trans_t *tp, | |
147 | xfs_ino_t ino, | |
148 | struct xfs_inode **ipp, | |
149 | xfs_daddr_t bno, | |
150 | int flags, | |
151 | int lock_flags) __releases(pag->pag_ici_lock) | |
152 | { | |
153 | struct xfs_inode *ip; | |
154 | int error; | |
155 | unsigned long first_index, mask; | |
156 | xfs_agino_t agino = XFS_INO_TO_AGINO(mp, ino); | |
1da177e4 | 157 | |
1da177e4 LT |
158 | /* |
159 | * Read the disk inode attributes into a new inode structure and get | |
160 | * a new vnode for it. This should also initialize i_ino and i_mount. | |
161 | */ | |
b48d8d64 | 162 | error = xfs_iread(mp, tp, ino, &ip, bno, flags); |
6441e549 | 163 | if (error) |
1da177e4 | 164 | return error; |
1da177e4 | 165 | |
15947f2d | 166 | xfs_itrace_exit_tag(ip, "xfs_iget.alloc"); |
1da177e4 | 167 | |
745b1f47 | 168 | if ((ip->i_d.di_mode == 0) && !(flags & XFS_IGET_CREATE)) { |
6441e549 DC |
169 | error = ENOENT; |
170 | goto out_destroy; | |
1da177e4 LT |
171 | } |
172 | ||
56e73ec4 DC |
173 | if (lock_flags) |
174 | xfs_ilock(ip, lock_flags); | |
175 | ||
1da177e4 | 176 | /* |
bad55843 | 177 | * Preload the radix tree so we can insert safely under the |
56e73ec4 DC |
178 | * write spinlock. Note that we cannot sleep inside the preload |
179 | * region. | |
1da177e4 | 180 | */ |
da353b0d | 181 | if (radix_tree_preload(GFP_KERNEL)) { |
6441e549 | 182 | error = EAGAIN; |
56e73ec4 | 183 | goto out_unlock; |
da353b0d | 184 | } |
f338f903 | 185 | |
da353b0d DC |
186 | mask = ~(((XFS_INODE_CLUSTER_SIZE(mp) >> mp->m_sb.sb_inodelog)) - 1); |
187 | first_index = agino & mask; | |
188 | write_lock(&pag->pag_ici_lock); | |
6441e549 DC |
189 | |
190 | /* insert the new inode */ | |
da353b0d DC |
191 | error = radix_tree_insert(&pag->pag_ici_root, agino, ip); |
192 | if (unlikely(error)) { | |
6441e549 | 193 | WARN_ON(error != -EEXIST); |
da353b0d | 194 | XFS_STATS_INC(xs_ig_dup); |
6441e549 | 195 | error = EAGAIN; |
56e73ec4 | 196 | goto out_preload_end; |
1da177e4 LT |
197 | } |
198 | ||
6441e549 | 199 | /* These values _must_ be set before releasing the radix tree lock! */ |
1da177e4 | 200 | ip->i_udquot = ip->i_gdquot = NULL; |
7a18c386 | 201 | xfs_iflags_set(ip, XFS_INEW); |
1da177e4 | 202 | |
da353b0d DC |
203 | write_unlock(&pag->pag_ici_lock); |
204 | radix_tree_preload_end(); | |
6441e549 DC |
205 | *ipp = ip; |
206 | return 0; | |
207 | ||
56e73ec4 | 208 | out_preload_end: |
6441e549 DC |
209 | write_unlock(&pag->pag_ici_lock); |
210 | radix_tree_preload_end(); | |
56e73ec4 DC |
211 | out_unlock: |
212 | if (lock_flags) | |
213 | xfs_iunlock(ip, lock_flags); | |
6441e549 | 214 | out_destroy: |
9ed0451e | 215 | xfs_destroy_inode(ip); |
6441e549 DC |
216 | return error; |
217 | } | |
218 | ||
219 | /* | |
220 | * Look up an inode by number in the given file system. | |
221 | * The inode is looked up in the cache held in each AG. | |
bf904248 DC |
222 | * If the inode is found in the cache, initialise the vfs inode |
223 | * if necessary. | |
6441e549 DC |
224 | * |
225 | * If it is not in core, read it in from the file system's device, | |
bf904248 | 226 | * add it to the cache and initialise the vfs inode. |
6441e549 DC |
227 | * |
228 | * The inode is locked according to the value of the lock_flags parameter. | |
229 | * This flag parameter indicates how and if the inode's IO lock and inode lock | |
230 | * should be taken. | |
231 | * | |
232 | * mp -- the mount point structure for the current file system. It points | |
233 | * to the inode hash table. | |
234 | * tp -- a pointer to the current transaction if there is one. This is | |
235 | * simply passed through to the xfs_iread() call. | |
236 | * ino -- the number of the inode desired. This is the unique identifier | |
237 | * within the file system for the inode being requested. | |
238 | * lock_flags -- flags indicating how to lock the inode. See the comment | |
239 | * for xfs_ilock() for a list of valid values. | |
240 | * bno -- the block number starting the buffer containing the inode, | |
241 | * if known (as by bulkstat), else 0. | |
242 | */ | |
bf904248 DC |
243 | int |
244 | xfs_iget( | |
6441e549 DC |
245 | xfs_mount_t *mp, |
246 | xfs_trans_t *tp, | |
247 | xfs_ino_t ino, | |
248 | uint flags, | |
249 | uint lock_flags, | |
250 | xfs_inode_t **ipp, | |
251 | xfs_daddr_t bno) | |
252 | { | |
253 | xfs_inode_t *ip; | |
254 | int error; | |
255 | xfs_perag_t *pag; | |
256 | xfs_agino_t agino; | |
257 | ||
258 | /* the radix tree exists only in inode capable AGs */ | |
259 | if (XFS_INO_TO_AGNO(mp, ino) >= mp->m_maxagi) | |
260 | return EINVAL; | |
261 | ||
262 | /* get the perag structure and ensure that it's inode capable */ | |
263 | pag = xfs_get_perag(mp, ino); | |
264 | if (!pag->pagi_inodeok) | |
265 | return EINVAL; | |
266 | ASSERT(pag->pag_ici_init); | |
267 | agino = XFS_INO_TO_AGINO(mp, ino); | |
268 | ||
269 | again: | |
270 | error = 0; | |
271 | read_lock(&pag->pag_ici_lock); | |
272 | ip = radix_tree_lookup(&pag->pag_ici_root, agino); | |
273 | ||
274 | if (ip) { | |
bf904248 | 275 | error = xfs_iget_cache_hit(pag, ip, flags, lock_flags); |
6441e549 DC |
276 | if (error) |
277 | goto out_error_or_again; | |
278 | } else { | |
279 | read_unlock(&pag->pag_ici_lock); | |
280 | XFS_STATS_INC(xs_ig_missed); | |
281 | ||
282 | error = xfs_iget_cache_miss(mp, pag, tp, ino, &ip, bno, | |
283 | flags, lock_flags); | |
284 | if (error) | |
285 | goto out_error_or_again; | |
286 | } | |
da353b0d | 287 | xfs_put_perag(mp, pag); |
1da177e4 | 288 | |
b3aea4ed | 289 | xfs_iflags_set(ip, XFS_IMODIFIED); |
1da177e4 LT |
290 | *ipp = ip; |
291 | ||
bf904248 DC |
292 | ASSERT(ip->i_df.if_ext_max == |
293 | XFS_IFORK_DSIZE(ip) / sizeof(xfs_bmbt_rec_t)); | |
1da177e4 LT |
294 | /* |
295 | * If we have a real type for an on-disk inode, we can set ops(&unlock) | |
296 | * now. If it's a new inode being created, xfs_ialloc will handle it. | |
297 | */ | |
bf904248 | 298 | if (xfs_iflags_test(ip, XFS_INEW) && ip->i_d.di_mode != 0) |
41be8bed | 299 | xfs_setup_inode(ip); |
1da177e4 | 300 | return 0; |
6441e549 DC |
301 | |
302 | out_error_or_again: | |
303 | if (error == EAGAIN) { | |
304 | delay(1); | |
305 | goto again; | |
306 | } | |
307 | xfs_put_perag(mp, pag); | |
308 | return error; | |
1da177e4 LT |
309 | } |
310 | ||
311 | ||
1da177e4 LT |
312 | /* |
313 | * Look for the inode corresponding to the given ino in the hash table. | |
314 | * If it is there and its i_transp pointer matches tp, return it. | |
315 | * Otherwise, return NULL. | |
316 | */ | |
317 | xfs_inode_t * | |
318 | xfs_inode_incore(xfs_mount_t *mp, | |
319 | xfs_ino_t ino, | |
320 | xfs_trans_t *tp) | |
321 | { | |
1da177e4 | 322 | xfs_inode_t *ip; |
da353b0d DC |
323 | xfs_perag_t *pag; |
324 | ||
325 | pag = xfs_get_perag(mp, ino); | |
326 | read_lock(&pag->pag_ici_lock); | |
327 | ip = radix_tree_lookup(&pag->pag_ici_root, XFS_INO_TO_AGINO(mp, ino)); | |
328 | read_unlock(&pag->pag_ici_lock); | |
329 | xfs_put_perag(mp, pag); | |
330 | ||
331 | /* the returned inode must match the transaction */ | |
332 | if (ip && (ip->i_transp != tp)) | |
333 | return NULL; | |
334 | return ip; | |
1da177e4 LT |
335 | } |
336 | ||
337 | /* | |
338 | * Decrement reference count of an inode structure and unlock it. | |
339 | * | |
340 | * ip -- the inode being released | |
341 | * lock_flags -- this parameter indicates the inode's locks to be | |
342 | * to be released. See the comment on xfs_iunlock() for a list | |
343 | * of valid values. | |
344 | */ | |
345 | void | |
346 | xfs_iput(xfs_inode_t *ip, | |
347 | uint lock_flags) | |
348 | { | |
cf441eeb | 349 | xfs_itrace_entry(ip); |
1da177e4 | 350 | xfs_iunlock(ip, lock_flags); |
10090be2 | 351 | IRELE(ip); |
1da177e4 LT |
352 | } |
353 | ||
354 | /* | |
355 | * Special iput for brand-new inodes that are still locked | |
356 | */ | |
357 | void | |
01651646 DC |
358 | xfs_iput_new( |
359 | xfs_inode_t *ip, | |
360 | uint lock_flags) | |
1da177e4 | 361 | { |
01651646 | 362 | struct inode *inode = VFS_I(ip); |
1da177e4 | 363 | |
cf441eeb | 364 | xfs_itrace_entry(ip); |
1da177e4 LT |
365 | |
366 | if ((ip->i_d.di_mode == 0)) { | |
7a18c386 | 367 | ASSERT(!xfs_iflags_test(ip, XFS_IRECLAIMABLE)); |
10090be2 | 368 | make_bad_inode(inode); |
1da177e4 LT |
369 | } |
370 | if (inode->i_state & I_NEW) | |
371 | unlock_new_inode(inode); | |
372 | if (lock_flags) | |
373 | xfs_iunlock(ip, lock_flags); | |
10090be2 | 374 | IRELE(ip); |
1da177e4 LT |
375 | } |
376 | ||
377 | ||
378 | /* | |
379 | * This routine embodies the part of the reclaim code that pulls | |
380 | * the inode from the inode hash table and the mount structure's | |
381 | * inode list. | |
382 | * This should only be called from xfs_reclaim(). | |
383 | */ | |
384 | void | |
385 | xfs_ireclaim(xfs_inode_t *ip) | |
386 | { | |
1da177e4 LT |
387 | /* |
388 | * Remove from old hash list and mount list. | |
389 | */ | |
390 | XFS_STATS_INC(xs_ig_reclaims); | |
391 | ||
392 | xfs_iextract(ip); | |
393 | ||
394 | /* | |
a4e4c4f4 DC |
395 | * Here we do a spurious inode lock in order to coordinate with inode |
396 | * cache radix tree lookups. This is because the lookup can reference | |
397 | * the inodes in the cache without taking references. We make that OK | |
398 | * here by ensuring that we wait until the inode is unlocked after the | |
399 | * lookup before we go ahead and free it. We get both the ilock and | |
400 | * the iolock because the code may need to drop the ilock one but will | |
401 | * still hold the iolock. | |
1da177e4 LT |
402 | */ |
403 | xfs_ilock(ip, XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL); | |
404 | ||
405 | /* | |
406 | * Release dquots (and their references) if any. An inode may escape | |
407 | * xfs_inactive and get here via vn_alloc->vn_reclaim path. | |
408 | */ | |
409 | XFS_QM_DQDETACH(ip->i_mount, ip); | |
410 | ||
1da177e4 LT |
411 | /* |
412 | * Free all memory associated with the inode. | |
413 | */ | |
439b8434 | 414 | xfs_iunlock(ip, XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL); |
1da177e4 LT |
415 | xfs_idestroy(ip); |
416 | } | |
417 | ||
418 | /* | |
419 | * This routine removes an about-to-be-destroyed inode from | |
420 | * all of the lists in which it is located with the exception | |
421 | * of the behavior chain. | |
422 | */ | |
423 | void | |
424 | xfs_iextract( | |
425 | xfs_inode_t *ip) | |
426 | { | |
da353b0d DC |
427 | xfs_mount_t *mp = ip->i_mount; |
428 | xfs_perag_t *pag = xfs_get_perag(mp, ip->i_ino); | |
da353b0d DC |
429 | |
430 | write_lock(&pag->pag_ici_lock); | |
431 | radix_tree_delete(&pag->pag_ici_root, XFS_INO_TO_AGINO(mp, ip->i_ino)); | |
432 | write_unlock(&pag->pag_ici_lock); | |
433 | xfs_put_perag(mp, pag); | |
1da177e4 | 434 | |
1da177e4 | 435 | mp->m_ireclaims++; |
1da177e4 LT |
436 | } |
437 | ||
438 | /* | |
439 | * This is a wrapper routine around the xfs_ilock() routine | |
440 | * used to centralize some grungy code. It is used in places | |
441 | * that wish to lock the inode solely for reading the extents. | |
442 | * The reason these places can't just call xfs_ilock(SHARED) | |
443 | * is that the inode lock also guards to bringing in of the | |
444 | * extents from disk for a file in b-tree format. If the inode | |
445 | * is in b-tree format, then we need to lock the inode exclusively | |
446 | * until the extents are read in. Locking it exclusively all | |
447 | * the time would limit our parallelism unnecessarily, though. | |
448 | * What we do instead is check to see if the extents have been | |
449 | * read in yet, and only lock the inode exclusively if they | |
450 | * have not. | |
451 | * | |
452 | * The function returns a value which should be given to the | |
453 | * corresponding xfs_iunlock_map_shared(). This value is | |
454 | * the mode in which the lock was actually taken. | |
455 | */ | |
456 | uint | |
457 | xfs_ilock_map_shared( | |
458 | xfs_inode_t *ip) | |
459 | { | |
460 | uint lock_mode; | |
461 | ||
462 | if ((ip->i_d.di_format == XFS_DINODE_FMT_BTREE) && | |
463 | ((ip->i_df.if_flags & XFS_IFEXTENTS) == 0)) { | |
464 | lock_mode = XFS_ILOCK_EXCL; | |
465 | } else { | |
466 | lock_mode = XFS_ILOCK_SHARED; | |
467 | } | |
468 | ||
469 | xfs_ilock(ip, lock_mode); | |
470 | ||
471 | return lock_mode; | |
472 | } | |
473 | ||
474 | /* | |
475 | * This is simply the unlock routine to go with xfs_ilock_map_shared(). | |
476 | * All it does is call xfs_iunlock() with the given lock_mode. | |
477 | */ | |
478 | void | |
479 | xfs_iunlock_map_shared( | |
480 | xfs_inode_t *ip, | |
481 | unsigned int lock_mode) | |
482 | { | |
483 | xfs_iunlock(ip, lock_mode); | |
484 | } | |
485 | ||
486 | /* | |
487 | * The xfs inode contains 2 locks: a multi-reader lock called the | |
488 | * i_iolock and a multi-reader lock called the i_lock. This routine | |
489 | * allows either or both of the locks to be obtained. | |
490 | * | |
491 | * The 2 locks should always be ordered so that the IO lock is | |
492 | * obtained first in order to prevent deadlock. | |
493 | * | |
494 | * ip -- the inode being locked | |
495 | * lock_flags -- this parameter indicates the inode's locks | |
496 | * to be locked. It can be: | |
497 | * XFS_IOLOCK_SHARED, | |
498 | * XFS_IOLOCK_EXCL, | |
499 | * XFS_ILOCK_SHARED, | |
500 | * XFS_ILOCK_EXCL, | |
501 | * XFS_IOLOCK_SHARED | XFS_ILOCK_SHARED, | |
502 | * XFS_IOLOCK_SHARED | XFS_ILOCK_EXCL, | |
503 | * XFS_IOLOCK_EXCL | XFS_ILOCK_SHARED, | |
504 | * XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL | |
505 | */ | |
506 | void | |
579aa9ca CH |
507 | xfs_ilock( |
508 | xfs_inode_t *ip, | |
509 | uint lock_flags) | |
1da177e4 LT |
510 | { |
511 | /* | |
512 | * You can't set both SHARED and EXCL for the same lock, | |
513 | * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED, | |
514 | * and XFS_ILOCK_EXCL are valid values to set in lock_flags. | |
515 | */ | |
516 | ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) != | |
517 | (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)); | |
518 | ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) != | |
519 | (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)); | |
f7c66ce3 | 520 | ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_DEP_MASK)) == 0); |
1da177e4 | 521 | |
579aa9ca | 522 | if (lock_flags & XFS_IOLOCK_EXCL) |
f7c66ce3 | 523 | mrupdate_nested(&ip->i_iolock, XFS_IOLOCK_DEP(lock_flags)); |
579aa9ca | 524 | else if (lock_flags & XFS_IOLOCK_SHARED) |
f7c66ce3 | 525 | mraccess_nested(&ip->i_iolock, XFS_IOLOCK_DEP(lock_flags)); |
579aa9ca CH |
526 | |
527 | if (lock_flags & XFS_ILOCK_EXCL) | |
f7c66ce3 | 528 | mrupdate_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags)); |
579aa9ca | 529 | else if (lock_flags & XFS_ILOCK_SHARED) |
f7c66ce3 | 530 | mraccess_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags)); |
579aa9ca | 531 | |
1da177e4 LT |
532 | xfs_ilock_trace(ip, 1, lock_flags, (inst_t *)__return_address); |
533 | } | |
534 | ||
535 | /* | |
536 | * This is just like xfs_ilock(), except that the caller | |
537 | * is guaranteed not to sleep. It returns 1 if it gets | |
538 | * the requested locks and 0 otherwise. If the IO lock is | |
539 | * obtained but the inode lock cannot be, then the IO lock | |
540 | * is dropped before returning. | |
541 | * | |
542 | * ip -- the inode being locked | |
543 | * lock_flags -- this parameter indicates the inode's locks to be | |
544 | * to be locked. See the comment for xfs_ilock() for a list | |
545 | * of valid values. | |
1da177e4 LT |
546 | */ |
547 | int | |
579aa9ca CH |
548 | xfs_ilock_nowait( |
549 | xfs_inode_t *ip, | |
550 | uint lock_flags) | |
1da177e4 | 551 | { |
1da177e4 LT |
552 | /* |
553 | * You can't set both SHARED and EXCL for the same lock, | |
554 | * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED, | |
555 | * and XFS_ILOCK_EXCL are valid values to set in lock_flags. | |
556 | */ | |
557 | ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) != | |
558 | (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)); | |
559 | ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) != | |
560 | (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)); | |
f7c66ce3 | 561 | ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_DEP_MASK)) == 0); |
1da177e4 | 562 | |
1da177e4 | 563 | if (lock_flags & XFS_IOLOCK_EXCL) { |
579aa9ca CH |
564 | if (!mrtryupdate(&ip->i_iolock)) |
565 | goto out; | |
1da177e4 | 566 | } else if (lock_flags & XFS_IOLOCK_SHARED) { |
579aa9ca CH |
567 | if (!mrtryaccess(&ip->i_iolock)) |
568 | goto out; | |
1da177e4 LT |
569 | } |
570 | if (lock_flags & XFS_ILOCK_EXCL) { | |
579aa9ca CH |
571 | if (!mrtryupdate(&ip->i_lock)) |
572 | goto out_undo_iolock; | |
1da177e4 | 573 | } else if (lock_flags & XFS_ILOCK_SHARED) { |
579aa9ca CH |
574 | if (!mrtryaccess(&ip->i_lock)) |
575 | goto out_undo_iolock; | |
1da177e4 LT |
576 | } |
577 | xfs_ilock_trace(ip, 2, lock_flags, (inst_t *)__return_address); | |
578 | return 1; | |
579aa9ca CH |
579 | |
580 | out_undo_iolock: | |
581 | if (lock_flags & XFS_IOLOCK_EXCL) | |
582 | mrunlock_excl(&ip->i_iolock); | |
583 | else if (lock_flags & XFS_IOLOCK_SHARED) | |
584 | mrunlock_shared(&ip->i_iolock); | |
585 | out: | |
586 | return 0; | |
1da177e4 LT |
587 | } |
588 | ||
589 | /* | |
590 | * xfs_iunlock() is used to drop the inode locks acquired with | |
591 | * xfs_ilock() and xfs_ilock_nowait(). The caller must pass | |
592 | * in the flags given to xfs_ilock() or xfs_ilock_nowait() so | |
593 | * that we know which locks to drop. | |
594 | * | |
595 | * ip -- the inode being unlocked | |
596 | * lock_flags -- this parameter indicates the inode's locks to be | |
597 | * to be unlocked. See the comment for xfs_ilock() for a list | |
598 | * of valid values for this parameter. | |
599 | * | |
600 | */ | |
601 | void | |
579aa9ca CH |
602 | xfs_iunlock( |
603 | xfs_inode_t *ip, | |
604 | uint lock_flags) | |
1da177e4 LT |
605 | { |
606 | /* | |
607 | * You can't set both SHARED and EXCL for the same lock, | |
608 | * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED, | |
609 | * and XFS_ILOCK_EXCL are valid values to set in lock_flags. | |
610 | */ | |
611 | ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) != | |
612 | (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)); | |
613 | ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) != | |
614 | (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)); | |
f7c66ce3 LM |
615 | ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_IUNLOCK_NONOTIFY | |
616 | XFS_LOCK_DEP_MASK)) == 0); | |
1da177e4 LT |
617 | ASSERT(lock_flags != 0); |
618 | ||
579aa9ca CH |
619 | if (lock_flags & XFS_IOLOCK_EXCL) |
620 | mrunlock_excl(&ip->i_iolock); | |
621 | else if (lock_flags & XFS_IOLOCK_SHARED) | |
622 | mrunlock_shared(&ip->i_iolock); | |
1da177e4 | 623 | |
579aa9ca CH |
624 | if (lock_flags & XFS_ILOCK_EXCL) |
625 | mrunlock_excl(&ip->i_lock); | |
626 | else if (lock_flags & XFS_ILOCK_SHARED) | |
627 | mrunlock_shared(&ip->i_lock); | |
1da177e4 | 628 | |
579aa9ca CH |
629 | if ((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) && |
630 | !(lock_flags & XFS_IUNLOCK_NONOTIFY) && ip->i_itemp) { | |
1da177e4 LT |
631 | /* |
632 | * Let the AIL know that this item has been unlocked in case | |
633 | * it is in the AIL and anyone is waiting on it. Don't do | |
634 | * this if the caller has asked us not to. | |
635 | */ | |
783a2f65 | 636 | xfs_trans_unlocked_item(ip->i_itemp->ili_item.li_ailp, |
579aa9ca | 637 | (xfs_log_item_t*)(ip->i_itemp)); |
1da177e4 LT |
638 | } |
639 | xfs_ilock_trace(ip, 3, lock_flags, (inst_t *)__return_address); | |
640 | } | |
641 | ||
642 | /* | |
643 | * give up write locks. the i/o lock cannot be held nested | |
644 | * if it is being demoted. | |
645 | */ | |
646 | void | |
579aa9ca CH |
647 | xfs_ilock_demote( |
648 | xfs_inode_t *ip, | |
649 | uint lock_flags) | |
1da177e4 LT |
650 | { |
651 | ASSERT(lock_flags & (XFS_IOLOCK_EXCL|XFS_ILOCK_EXCL)); | |
652 | ASSERT((lock_flags & ~(XFS_IOLOCK_EXCL|XFS_ILOCK_EXCL)) == 0); | |
653 | ||
579aa9ca | 654 | if (lock_flags & XFS_ILOCK_EXCL) |
1da177e4 | 655 | mrdemote(&ip->i_lock); |
579aa9ca | 656 | if (lock_flags & XFS_IOLOCK_EXCL) |
1da177e4 | 657 | mrdemote(&ip->i_iolock); |
579aa9ca CH |
658 | } |
659 | ||
660 | #ifdef DEBUG | |
661 | /* | |
662 | * Debug-only routine, without additional rw_semaphore APIs, we can | |
663 | * now only answer requests regarding whether we hold the lock for write | |
664 | * (reader state is outside our visibility, we only track writer state). | |
665 | * | |
666 | * Note: this means !xfs_isilocked would give false positives, so don't do that. | |
667 | */ | |
668 | int | |
669 | xfs_isilocked( | |
670 | xfs_inode_t *ip, | |
671 | uint lock_flags) | |
672 | { | |
673 | if ((lock_flags & (XFS_ILOCK_EXCL|XFS_ILOCK_SHARED)) == | |
674 | XFS_ILOCK_EXCL) { | |
675 | if (!ip->i_lock.mr_writer) | |
676 | return 0; | |
1da177e4 | 677 | } |
579aa9ca CH |
678 | |
679 | if ((lock_flags & (XFS_IOLOCK_EXCL|XFS_IOLOCK_SHARED)) == | |
680 | XFS_IOLOCK_EXCL) { | |
681 | if (!ip->i_iolock.mr_writer) | |
682 | return 0; | |
683 | } | |
684 | ||
685 | return 1; | |
1da177e4 | 686 | } |
579aa9ca | 687 | #endif |
1da177e4 | 688 |