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2 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
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.
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.
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
20 #include "xfs_types.h"
24 #include "xfs_trans.h"
29 #include "xfs_dmapi.h"
30 #include "xfs_mount.h"
31 #include "xfs_bmap_btree.h"
32 #include "xfs_alloc_btree.h"
33 #include "xfs_ialloc_btree.h"
34 #include "xfs_dir_sf.h"
35 #include "xfs_dir2_sf.h"
36 #include "xfs_attr_sf.h"
37 #include "xfs_dinode.h"
38 #include "xfs_inode.h"
39 #include "xfs_btree.h"
40 #include "xfs_ialloc.h"
41 #include "xfs_quota.h"
42 #include "xfs_utils.h"
45 * Initialize the inode hash table for the newly mounted file system.
46 * Choose an initial table size based on user specified value, else
47 * use a simple algorithm using the maximum number of inodes as an
48 * indicator for table size, and clamp it between one and some large
52 xfs_ihash_init(xfs_mount_t
*mp
)
55 uint i
, flags
= KM_SLEEP
| KM_MAYFAIL
;
58 icount
= mp
->m_maxicount
? mp
->m_maxicount
:
59 (mp
->m_sb
.sb_dblocks
<< mp
->m_sb
.sb_inopblog
);
60 mp
->m_ihsize
= 1 << max_t(uint
, 8,
61 (xfs_highbit64(icount
) + 1) / 2);
62 mp
->m_ihsize
= min_t(uint
, mp
->m_ihsize
,
63 (64 * NBPP
) / sizeof(xfs_ihash_t
));
66 while (!(mp
->m_ihash
= (xfs_ihash_t
*)kmem_zalloc(mp
->m_ihsize
*
67 sizeof(xfs_ihash_t
), flags
))) {
68 if ((mp
->m_ihsize
>>= 1) <= NBPP
)
71 for (i
= 0; i
< mp
->m_ihsize
; i
++) {
72 rwlock_init(&(mp
->m_ihash
[i
].ih_lock
));
77 * Free up structures allocated by xfs_ihash_init, at unmount time.
80 xfs_ihash_free(xfs_mount_t
*mp
)
82 kmem_free(mp
->m_ihash
, mp
->m_ihsize
*sizeof(xfs_ihash_t
));
87 * Initialize the inode cluster hash table for the newly mounted file system.
88 * Its size is derived from the ihash table size.
91 xfs_chash_init(xfs_mount_t
*mp
)
95 mp
->m_chsize
= max_t(uint
, 1, mp
->m_ihsize
/
96 (XFS_INODE_CLUSTER_SIZE(mp
) >> mp
->m_sb
.sb_inodelog
));
97 mp
->m_chsize
= min_t(uint
, mp
->m_chsize
, mp
->m_ihsize
);
98 mp
->m_chash
= (xfs_chash_t
*)kmem_zalloc(mp
->m_chsize
99 * sizeof(xfs_chash_t
),
101 for (i
= 0; i
< mp
->m_chsize
; i
++) {
102 spinlock_init(&mp
->m_chash
[i
].ch_lock
,"xfshash");
107 * Free up structures allocated by xfs_chash_init, at unmount time.
110 xfs_chash_free(xfs_mount_t
*mp
)
114 for (i
= 0; i
< mp
->m_chsize
; i
++) {
115 spinlock_destroy(&mp
->m_chash
[i
].ch_lock
);
118 kmem_free(mp
->m_chash
, mp
->m_chsize
*sizeof(xfs_chash_t
));
123 * Try to move an inode to the front of its hash list if possible
124 * (and if its not there already). Called right after obtaining
125 * the list version number and then dropping the read_lock on the
126 * hash list in question (which is done right after looking up the
127 * inode in question...).
137 if ((ip
->i_prevp
!= &ih
->ih_next
) && write_trylock(&ih
->ih_lock
)) {
138 if (likely(version
== ih
->ih_version
)) {
139 /* remove from list */
140 if ((iq
= ip
->i_next
)) {
141 iq
->i_prevp
= ip
->i_prevp
;
145 /* insert at list head */
147 iq
->i_prevp
= &ip
->i_next
;
149 ip
->i_prevp
= &ih
->ih_next
;
152 write_unlock(&ih
->ih_lock
);
157 * Look up an inode by number in the given file system.
158 * The inode is looked up in the hash table for the file system
159 * represented by the mount point parameter mp. Each bucket of
160 * the hash table is guarded by an individual semaphore.
162 * If the inode is found in the hash table, its corresponding vnode
163 * is obtained with a call to vn_get(). This call takes care of
164 * coordination with the reclamation of the inode and vnode. Note
165 * that the vmap structure is filled in while holding the hash lock.
166 * This gives us the state of the inode/vnode when we found it and
167 * is used for coordination in vn_get().
169 * If it is not in core, read it in from the file system's device and
170 * add the inode into the hash table.
172 * The inode is locked according to the value of the lock_flags parameter.
173 * This flag parameter indicates how and if the inode's IO lock and inode lock
176 * mp -- the mount point structure for the current file system. It points
177 * to the inode hash table.
178 * tp -- a pointer to the current transaction if there is one. This is
179 * simply passed through to the xfs_iread() call.
180 * ino -- the number of the inode desired. This is the unique identifier
181 * within the file system for the inode being requested.
182 * lock_flags -- flags indicating how to lock the inode. See the comment
183 * for xfs_ilock() for a list of valid values.
184 * bno -- the block number starting the buffer containing the inode,
185 * if known (as by bulkstat), else 0.
201 bhv_vnode_t
*inode_vp
;
206 xfs_chashlist_t
*chl
, *chlnew
;
210 ih
= XFS_IHASH(mp
, ino
);
213 read_lock(&ih
->ih_lock
);
215 for (ip
= ih
->ih_next
; ip
!= NULL
; ip
= ip
->i_next
) {
216 if (ip
->i_ino
== ino
) {
218 * If INEW is set this inode is being set up
219 * we need to pause and try again.
221 if (ip
->i_flags
& XFS_INEW
) {
222 read_unlock(&ih
->ih_lock
);
224 XFS_STATS_INC(xs_ig_frecycle
);
229 inode_vp
= XFS_ITOV_NULL(ip
);
230 if (inode_vp
== NULL
) {
232 * If IRECLAIM is set this inode is
233 * on its way out of the system,
234 * we need to pause and try again.
236 if (ip
->i_flags
& XFS_IRECLAIM
) {
237 read_unlock(&ih
->ih_lock
);
239 XFS_STATS_INC(xs_ig_frecycle
);
244 vn_trace_exit(vp
, "xfs_iget.alloc",
245 (inst_t
*)__return_address
);
247 XFS_STATS_INC(xs_ig_found
);
249 ip
->i_flags
&= ~XFS_IRECLAIMABLE
;
250 version
= ih
->ih_version
;
251 read_unlock(&ih
->ih_lock
);
252 xfs_ihash_promote(ih
, ip
, version
);
255 list_del_init(&ip
->i_reclaim
);
256 XFS_MOUNT_IUNLOCK(mp
);
260 } else if (vp
!= inode_vp
) {
261 struct inode
*inode
= vn_to_inode(inode_vp
);
263 /* The inode is being torn down, pause and
266 if (inode
->i_state
& (I_FREEING
| I_CLEAR
)) {
267 read_unlock(&ih
->ih_lock
);
269 XFS_STATS_INC(xs_ig_frecycle
);
273 /* Chances are the other vnode (the one in the inode) is being torn
274 * down right now, and we landed on top of it. Question is, what do
275 * we do? Unhook the old inode and hook up the new one?
278 "xfs_iget_core: ambiguous vns: vp/0x%p, invp/0x%p",
283 * Inode cache hit: if ip is not at the front of
284 * its hash chain, move it there now.
285 * Do this with the lock held for update, but
286 * do statistics after releasing the lock.
288 version
= ih
->ih_version
;
289 read_unlock(&ih
->ih_lock
);
290 xfs_ihash_promote(ih
, ip
, version
);
291 XFS_STATS_INC(xs_ig_found
);
294 if (ip
->i_d
.di_mode
== 0) {
295 if (!(flags
& IGET_CREATE
))
297 xfs_iocore_inode_reinit(ip
);
301 xfs_ilock(ip
, lock_flags
);
303 ip
->i_flags
&= ~XFS_ISTALE
;
305 vn_trace_exit(vp
, "xfs_iget.found",
306 (inst_t
*)__return_address
);
312 * Inode cache miss: save the hash chain version stamp and unlock
313 * the chain, so we don't deadlock in vn_alloc.
315 XFS_STATS_INC(xs_ig_missed
);
317 version
= ih
->ih_version
;
319 read_unlock(&ih
->ih_lock
);
322 * Read the disk inode attributes into a new inode structure and get
323 * a new vnode for it. This should also initialize i_ino and i_mount.
325 error
= xfs_iread(mp
, tp
, ino
, &ip
, bno
);
330 vn_trace_exit(vp
, "xfs_iget.alloc", (inst_t
*)__return_address
);
332 xfs_inode_lock_init(ip
, vp
);
333 xfs_iocore_inode_init(ip
);
335 if (lock_flags
!= 0) {
336 xfs_ilock(ip
, lock_flags
);
339 if ((ip
->i_d
.di_mode
== 0) && !(flags
& IGET_CREATE
)) {
345 * Put ip on its hash chain, unless someone else hashed a duplicate
346 * after we released the hash lock.
348 write_lock(&ih
->ih_lock
);
350 if (ih
->ih_version
!= version
) {
351 for (iq
= ih
->ih_next
; iq
!= NULL
; iq
= iq
->i_next
) {
352 if (iq
->i_ino
== ino
) {
353 write_unlock(&ih
->ih_lock
);
356 XFS_STATS_INC(xs_ig_dup
);
363 * These values _must_ be set before releasing ihlock!
366 if ((iq
= ih
->ih_next
)) {
367 iq
->i_prevp
= &ip
->i_next
;
370 ip
->i_prevp
= &ih
->ih_next
;
372 ip
->i_udquot
= ip
->i_gdquot
= NULL
;
374 ip
->i_flags
|= XFS_INEW
;
376 write_unlock(&ih
->ih_lock
);
379 * put ip on its cluster's hash chain
381 ASSERT(ip
->i_chash
== NULL
&& ip
->i_cprev
== NULL
&&
382 ip
->i_cnext
== NULL
);
385 ch
= XFS_CHASH(mp
, ip
->i_blkno
);
387 s
= mutex_spinlock(&ch
->ch_lock
);
388 for (chl
= ch
->ch_list
; chl
!= NULL
; chl
= chl
->chl_next
) {
389 if (chl
->chl_blkno
== ip
->i_blkno
) {
391 /* insert this inode into the doubly-linked list
392 * where chl points */
393 if ((iq
= chl
->chl_ip
)) {
394 ip
->i_cprev
= iq
->i_cprev
;
395 iq
->i_cprev
->i_cnext
= ip
;
408 /* no hash list found for this block; add a new hash list */
410 if (chlnew
== NULL
) {
411 mutex_spinunlock(&ch
->ch_lock
, s
);
412 ASSERT(xfs_chashlist_zone
!= NULL
);
413 chlnew
= (xfs_chashlist_t
*)
414 kmem_zone_alloc(xfs_chashlist_zone
,
416 ASSERT(chlnew
!= NULL
);
421 ip
->i_chash
= chlnew
;
423 chlnew
->chl_blkno
= ip
->i_blkno
;
425 ch
->ch_list
->chl_prev
= chlnew
;
426 chlnew
->chl_next
= ch
->ch_list
;
427 chlnew
->chl_prev
= NULL
;
428 ch
->ch_list
= chlnew
;
432 if (chlnew
!= NULL
) {
433 kmem_zone_free(xfs_chashlist_zone
, chlnew
);
437 mutex_spinunlock(&ch
->ch_lock
, s
);
441 * Link ip to its mount and thread it on the mount's inode list.
444 if ((iq
= mp
->m_inodes
)) {
445 ASSERT(iq
->i_mprev
->i_mnext
== iq
);
446 ip
->i_mprev
= iq
->i_mprev
;
447 iq
->i_mprev
->i_mnext
= ip
;
456 XFS_MOUNT_IUNLOCK(mp
);
459 ASSERT(ip
->i_df
.if_ext_max
==
460 XFS_IFORK_DSIZE(ip
) / sizeof(xfs_bmbt_rec_t
));
462 ASSERT(((ip
->i_d
.di_flags
& XFS_DIFLAG_REALTIME
) != 0) ==
463 ((ip
->i_iocore
.io_flags
& XFS_IOCORE_RT
) != 0));
468 * If we have a real type for an on-disk inode, we can set ops(&unlock)
469 * now. If it's a new inode being created, xfs_ialloc will handle it.
471 bhv_vfs_init_vnode(XFS_MTOVFS(mp
), vp
, XFS_ITOBHV(ip
), 1);
478 * The 'normal' internal xfs_iget, if needed it will
479 * 'allocate', or 'get', the vnode.
492 bhv_vnode_t
*vp
= NULL
;
495 XFS_STATS_INC(xs_ig_attempts
);
498 if ((inode
= iget_locked(XFS_MTOVFS(mp
)->vfs_super
, ino
))) {
501 vp
= vn_from_inode(inode
);
502 if (inode
->i_state
& I_NEW
) {
503 vn_initialize(inode
);
504 error
= xfs_iget_core(vp
, mp
, tp
, ino
, flags
,
505 lock_flags
, ipp
, bno
);
508 if (inode
->i_state
& I_NEW
)
509 unlock_new_inode(inode
);
514 * If the inode is not fully constructed due to
515 * filehandle mismatches wait for the inode to go
516 * away and try again.
518 * iget_locked will call __wait_on_freeing_inode
519 * to wait for the inode to go away.
521 if (is_bad_inode(inode
) ||
522 ((ip
= xfs_vtoi(vp
)) == NULL
)) {
529 xfs_ilock(ip
, lock_flags
);
530 XFS_STATS_INC(xs_ig_found
);
535 error
= ENOMEM
; /* If we got no inode we are out of memory */
541 * Do the setup for the various locks within the incore inode.
548 mrlock_init(&ip
->i_lock
, MRLOCK_ALLOW_EQUAL_PRI
|MRLOCK_BARRIER
,
549 "xfsino", (long)vp
->v_number
);
550 mrlock_init(&ip
->i_iolock
, MRLOCK_BARRIER
, "xfsio", vp
->v_number
);
551 init_waitqueue_head(&ip
->i_ipin_wait
);
552 atomic_set(&ip
->i_pincount
, 0);
553 init_sema(&ip
->i_flock
, 1, "xfsfino", vp
->v_number
);
557 * Look for the inode corresponding to the given ino in the hash table.
558 * If it is there and its i_transp pointer matches tp, return it.
559 * Otherwise, return NULL.
562 xfs_inode_incore(xfs_mount_t
*mp
,
570 ih
= XFS_IHASH(mp
, ino
);
571 read_lock(&ih
->ih_lock
);
572 for (ip
= ih
->ih_next
; ip
!= NULL
; ip
= ip
->i_next
) {
573 if (ip
->i_ino
== ino
) {
575 * If we find it and tp matches, return it.
576 * Also move it to the front of the hash list
577 * if we find it and it is not already there.
578 * Otherwise break from the loop and return
581 if (ip
->i_transp
== tp
) {
582 version
= ih
->ih_version
;
583 read_unlock(&ih
->ih_lock
);
584 xfs_ihash_promote(ih
, ip
, version
);
590 read_unlock(&ih
->ih_lock
);
595 * Decrement reference count of an inode structure and unlock it.
597 * ip -- the inode being released
598 * lock_flags -- this parameter indicates the inode's locks to be
599 * to be released. See the comment on xfs_iunlock() for a list
603 xfs_iput(xfs_inode_t
*ip
,
606 bhv_vnode_t
*vp
= XFS_ITOV(ip
);
608 vn_trace_entry(vp
, "xfs_iput", (inst_t
*)__return_address
);
609 xfs_iunlock(ip
, lock_flags
);
614 * Special iput for brand-new inodes that are still locked
617 xfs_iput_new(xfs_inode_t
*ip
,
620 bhv_vnode_t
*vp
= XFS_ITOV(ip
);
621 struct inode
*inode
= vn_to_inode(vp
);
623 vn_trace_entry(vp
, "xfs_iput_new", (inst_t
*)__return_address
);
625 if ((ip
->i_d
.di_mode
== 0)) {
626 ASSERT(!(ip
->i_flags
& XFS_IRECLAIMABLE
));
629 if (inode
->i_state
& I_NEW
)
630 unlock_new_inode(inode
);
632 xfs_iunlock(ip
, lock_flags
);
638 * This routine embodies the part of the reclaim code that pulls
639 * the inode from the inode hash table and the mount structure's
641 * This should only be called from xfs_reclaim().
644 xfs_ireclaim(xfs_inode_t
*ip
)
649 * Remove from old hash list and mount list.
651 XFS_STATS_INC(xs_ig_reclaims
);
656 * Here we do a spurious inode lock in order to coordinate with
657 * xfs_sync(). This is because xfs_sync() references the inodes
658 * in the mount list without taking references on the corresponding
659 * vnodes. We make that OK here by ensuring that we wait until
660 * the inode is unlocked in xfs_sync() before we go ahead and
661 * free it. We get both the regular lock and the io lock because
662 * the xfs_sync() code may need to drop the regular one but will
663 * still hold the io lock.
665 xfs_ilock(ip
, XFS_ILOCK_EXCL
| XFS_IOLOCK_EXCL
);
668 * Release dquots (and their references) if any. An inode may escape
669 * xfs_inactive and get here via vn_alloc->vn_reclaim path.
671 XFS_QM_DQDETACH(ip
->i_mount
, ip
);
674 * Pull our behavior descriptor from the vnode chain.
676 vp
= XFS_ITOV_NULL(ip
);
678 vn_bhv_remove(VN_BHV_HEAD(vp
), XFS_ITOBHV(ip
));
682 * Free all memory associated with the inode.
688 * This routine removes an about-to-be-destroyed inode from
689 * all of the lists in which it is located with the exception
690 * of the behavior chain.
700 xfs_chashlist_t
*chl
, *chm
;
704 write_lock(&ih
->ih_lock
);
705 if ((iq
= ip
->i_next
)) {
706 iq
->i_prevp
= ip
->i_prevp
;
710 write_unlock(&ih
->ih_lock
);
713 * Remove from cluster hash list
714 * 1) delete the chashlist if this is the last inode on the chashlist
715 * 2) unchain from list of inodes
716 * 3) point chashlist->chl_ip to 'chl_next' if to this inode.
719 ch
= XFS_CHASH(mp
, ip
->i_blkno
);
720 s
= mutex_spinlock(&ch
->ch_lock
);
722 if (ip
->i_cnext
== ip
) {
723 /* Last inode on chashlist */
724 ASSERT(ip
->i_cnext
== ip
&& ip
->i_cprev
== ip
);
725 ASSERT(ip
->i_chash
!= NULL
);
729 chl
->chl_prev
->chl_next
= chl
->chl_next
;
731 ch
->ch_list
= chl
->chl_next
;
733 chl
->chl_next
->chl_prev
= chl
->chl_prev
;
734 kmem_zone_free(xfs_chashlist_zone
, chl
);
736 /* delete one inode from a non-empty list */
738 iq
->i_cprev
= ip
->i_cprev
;
739 ip
->i_cprev
->i_cnext
= iq
;
740 if (ip
->i_chash
->chl_ip
== ip
) {
741 ip
->i_chash
->chl_ip
= iq
;
743 ip
->i_chash
= __return_address
;
744 ip
->i_cprev
= __return_address
;
745 ip
->i_cnext
= __return_address
;
747 mutex_spinunlock(&ch
->ch_lock
, s
);
750 * Remove from mount's inode list.
753 ASSERT((ip
->i_mnext
!= NULL
) && (ip
->i_mprev
!= NULL
));
755 iq
->i_mprev
= ip
->i_mprev
;
756 ip
->i_mprev
->i_mnext
= iq
;
759 * Fix up the head pointer if it points to the inode being deleted.
761 if (mp
->m_inodes
== ip
) {
769 /* Deal with the deleted inodes list */
770 list_del_init(&ip
->i_reclaim
);
773 XFS_MOUNT_IUNLOCK(mp
);
777 * This is a wrapper routine around the xfs_ilock() routine
778 * used to centralize some grungy code. It is used in places
779 * that wish to lock the inode solely for reading the extents.
780 * The reason these places can't just call xfs_ilock(SHARED)
781 * is that the inode lock also guards to bringing in of the
782 * extents from disk for a file in b-tree format. If the inode
783 * is in b-tree format, then we need to lock the inode exclusively
784 * until the extents are read in. Locking it exclusively all
785 * the time would limit our parallelism unnecessarily, though.
786 * What we do instead is check to see if the extents have been
787 * read in yet, and only lock the inode exclusively if they
790 * The function returns a value which should be given to the
791 * corresponding xfs_iunlock_map_shared(). This value is
792 * the mode in which the lock was actually taken.
795 xfs_ilock_map_shared(
800 if ((ip
->i_d
.di_format
== XFS_DINODE_FMT_BTREE
) &&
801 ((ip
->i_df
.if_flags
& XFS_IFEXTENTS
) == 0)) {
802 lock_mode
= XFS_ILOCK_EXCL
;
804 lock_mode
= XFS_ILOCK_SHARED
;
807 xfs_ilock(ip
, lock_mode
);
813 * This is simply the unlock routine to go with xfs_ilock_map_shared().
814 * All it does is call xfs_iunlock() with the given lock_mode.
817 xfs_iunlock_map_shared(
819 unsigned int lock_mode
)
821 xfs_iunlock(ip
, lock_mode
);
825 * The xfs inode contains 2 locks: a multi-reader lock called the
826 * i_iolock and a multi-reader lock called the i_lock. This routine
827 * allows either or both of the locks to be obtained.
829 * The 2 locks should always be ordered so that the IO lock is
830 * obtained first in order to prevent deadlock.
832 * ip -- the inode being locked
833 * lock_flags -- this parameter indicates the inode's locks
834 * to be locked. It can be:
839 * XFS_IOLOCK_SHARED | XFS_ILOCK_SHARED,
840 * XFS_IOLOCK_SHARED | XFS_ILOCK_EXCL,
841 * XFS_IOLOCK_EXCL | XFS_ILOCK_SHARED,
842 * XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL
845 xfs_ilock(xfs_inode_t
*ip
,
849 * You can't set both SHARED and EXCL for the same lock,
850 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
851 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
853 ASSERT((lock_flags
& (XFS_IOLOCK_SHARED
| XFS_IOLOCK_EXCL
)) !=
854 (XFS_IOLOCK_SHARED
| XFS_IOLOCK_EXCL
));
855 ASSERT((lock_flags
& (XFS_ILOCK_SHARED
| XFS_ILOCK_EXCL
)) !=
856 (XFS_ILOCK_SHARED
| XFS_ILOCK_EXCL
));
857 ASSERT((lock_flags
& ~XFS_LOCK_MASK
) == 0);
859 if (lock_flags
& XFS_IOLOCK_EXCL
) {
860 mrupdate(&ip
->i_iolock
);
861 } else if (lock_flags
& XFS_IOLOCK_SHARED
) {
862 mraccess(&ip
->i_iolock
);
864 if (lock_flags
& XFS_ILOCK_EXCL
) {
865 mrupdate(&ip
->i_lock
);
866 } else if (lock_flags
& XFS_ILOCK_SHARED
) {
867 mraccess(&ip
->i_lock
);
869 xfs_ilock_trace(ip
, 1, lock_flags
, (inst_t
*)__return_address
);
873 * This is just like xfs_ilock(), except that the caller
874 * is guaranteed not to sleep. It returns 1 if it gets
875 * the requested locks and 0 otherwise. If the IO lock is
876 * obtained but the inode lock cannot be, then the IO lock
877 * is dropped before returning.
879 * ip -- the inode being locked
880 * lock_flags -- this parameter indicates the inode's locks to be
881 * to be locked. See the comment for xfs_ilock() for a list
886 xfs_ilock_nowait(xfs_inode_t
*ip
,
893 * You can't set both SHARED and EXCL for the same lock,
894 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
895 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
897 ASSERT((lock_flags
& (XFS_IOLOCK_SHARED
| XFS_IOLOCK_EXCL
)) !=
898 (XFS_IOLOCK_SHARED
| XFS_IOLOCK_EXCL
));
899 ASSERT((lock_flags
& (XFS_ILOCK_SHARED
| XFS_ILOCK_EXCL
)) !=
900 (XFS_ILOCK_SHARED
| XFS_ILOCK_EXCL
));
901 ASSERT((lock_flags
& ~XFS_LOCK_MASK
) == 0);
904 if (lock_flags
& XFS_IOLOCK_EXCL
) {
905 iolocked
= mrtryupdate(&ip
->i_iolock
);
909 } else if (lock_flags
& XFS_IOLOCK_SHARED
) {
910 iolocked
= mrtryaccess(&ip
->i_iolock
);
915 if (lock_flags
& XFS_ILOCK_EXCL
) {
916 ilocked
= mrtryupdate(&ip
->i_lock
);
919 mrunlock(&ip
->i_iolock
);
923 } else if (lock_flags
& XFS_ILOCK_SHARED
) {
924 ilocked
= mrtryaccess(&ip
->i_lock
);
927 mrunlock(&ip
->i_iolock
);
932 xfs_ilock_trace(ip
, 2, lock_flags
, (inst_t
*)__return_address
);
937 * xfs_iunlock() is used to drop the inode locks acquired with
938 * xfs_ilock() and xfs_ilock_nowait(). The caller must pass
939 * in the flags given to xfs_ilock() or xfs_ilock_nowait() so
940 * that we know which locks to drop.
942 * ip -- the inode being unlocked
943 * lock_flags -- this parameter indicates the inode's locks to be
944 * to be unlocked. See the comment for xfs_ilock() for a list
945 * of valid values for this parameter.
949 xfs_iunlock(xfs_inode_t
*ip
,
953 * You can't set both SHARED and EXCL for the same lock,
954 * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED,
955 * and XFS_ILOCK_EXCL are valid values to set in lock_flags.
957 ASSERT((lock_flags
& (XFS_IOLOCK_SHARED
| XFS_IOLOCK_EXCL
)) !=
958 (XFS_IOLOCK_SHARED
| XFS_IOLOCK_EXCL
));
959 ASSERT((lock_flags
& (XFS_ILOCK_SHARED
| XFS_ILOCK_EXCL
)) !=
960 (XFS_ILOCK_SHARED
| XFS_ILOCK_EXCL
));
961 ASSERT((lock_flags
& ~(XFS_LOCK_MASK
| XFS_IUNLOCK_NONOTIFY
)) == 0);
962 ASSERT(lock_flags
!= 0);
964 if (lock_flags
& (XFS_IOLOCK_SHARED
| XFS_IOLOCK_EXCL
)) {
965 ASSERT(!(lock_flags
& XFS_IOLOCK_SHARED
) ||
966 (ismrlocked(&ip
->i_iolock
, MR_ACCESS
)));
967 ASSERT(!(lock_flags
& XFS_IOLOCK_EXCL
) ||
968 (ismrlocked(&ip
->i_iolock
, MR_UPDATE
)));
969 mrunlock(&ip
->i_iolock
);
972 if (lock_flags
& (XFS_ILOCK_SHARED
| XFS_ILOCK_EXCL
)) {
973 ASSERT(!(lock_flags
& XFS_ILOCK_SHARED
) ||
974 (ismrlocked(&ip
->i_lock
, MR_ACCESS
)));
975 ASSERT(!(lock_flags
& XFS_ILOCK_EXCL
) ||
976 (ismrlocked(&ip
->i_lock
, MR_UPDATE
)));
977 mrunlock(&ip
->i_lock
);
980 * Let the AIL know that this item has been unlocked in case
981 * it is in the AIL and anyone is waiting on it. Don't do
982 * this if the caller has asked us not to.
984 if (!(lock_flags
& XFS_IUNLOCK_NONOTIFY
) &&
985 ip
->i_itemp
!= NULL
) {
986 xfs_trans_unlocked_item(ip
->i_mount
,
987 (xfs_log_item_t
*)(ip
->i_itemp
));
990 xfs_ilock_trace(ip
, 3, lock_flags
, (inst_t
*)__return_address
);
994 * give up write locks. the i/o lock cannot be held nested
995 * if it is being demoted.
998 xfs_ilock_demote(xfs_inode_t
*ip
,
1001 ASSERT(lock_flags
& (XFS_IOLOCK_EXCL
|XFS_ILOCK_EXCL
));
1002 ASSERT((lock_flags
& ~(XFS_IOLOCK_EXCL
|XFS_ILOCK_EXCL
)) == 0);
1004 if (lock_flags
& XFS_ILOCK_EXCL
) {
1005 ASSERT(ismrlocked(&ip
->i_lock
, MR_UPDATE
));
1006 mrdemote(&ip
->i_lock
);
1008 if (lock_flags
& XFS_IOLOCK_EXCL
) {
1009 ASSERT(ismrlocked(&ip
->i_iolock
, MR_UPDATE
));
1010 mrdemote(&ip
->i_iolock
);
1015 * The following three routines simply manage the i_flock
1016 * semaphore embedded in the inode. This semaphore synchronizes
1017 * processes attempting to flush the in-core inode back to disk.
1020 xfs_iflock(xfs_inode_t
*ip
)
1022 psema(&(ip
->i_flock
), PINOD
|PLTWAIT
);
1026 xfs_iflock_nowait(xfs_inode_t
*ip
)
1028 return (cpsema(&(ip
->i_flock
)));
1032 xfs_ifunlock(xfs_inode_t
*ip
)
1034 ASSERT(valusema(&(ip
->i_flock
)) <= 0);
1035 vsema(&(ip
->i_flock
));