diff options
Diffstat (limited to 'sys/gnu/fs/xfs/xfs_iget.c')
| -rw-r--r-- | sys/gnu/fs/xfs/xfs_iget.c | 1052 |
1 files changed, 0 insertions, 1052 deletions
diff --git a/sys/gnu/fs/xfs/xfs_iget.c b/sys/gnu/fs/xfs/xfs_iget.c deleted file mode 100644 index 7b5803c..0000000 --- a/sys/gnu/fs/xfs/xfs_iget.c +++ /dev/null @@ -1,1052 +0,0 @@ -/* - * Copyright (c) 2000-2005 Silicon Graphics, Inc. - * All Rights Reserved. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License as - * published by the Free Software Foundation. - * - * This program is distributed in the hope that it would be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write the Free Software Foundation, - * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA - */ -#include "xfs.h" -#include "xfs_fs.h" -#include "xfs_types.h" -#include "xfs_bit.h" -#include "xfs_log.h" -#include "xfs_inum.h" -#include "xfs_trans.h" -#include "xfs_sb.h" -#include "xfs_ag.h" -#include "xfs_dir.h" -#include "xfs_dir2.h" -#include "xfs_dmapi.h" -#include "xfs_mount.h" -#include "xfs_bmap_btree.h" -#include "xfs_alloc_btree.h" -#include "xfs_ialloc_btree.h" -#include "xfs_dir_sf.h" -#include "xfs_dir2_sf.h" -#include "xfs_attr_sf.h" -#include "xfs_dinode.h" -#include "xfs_inode.h" -#include "xfs_btree.h" -#include "xfs_ialloc.h" -#include "xfs_quota.h" -#include "xfs_utils.h" - -/* - * Initialize the inode hash table for the newly mounted file system. - * Choose an initial table size based on user specified value, else - * use a simple algorithm using the maximum number of inodes as an - * indicator for table size, and clamp it between one and some large - * number of pages. - */ -void -xfs_ihash_init(xfs_mount_t *mp) -{ - __uint64_t icount; - uint i, flags = KM_SLEEP | KM_MAYFAIL; - - if (!mp->m_ihsize) { - icount = mp->m_maxicount ? mp->m_maxicount : - (mp->m_sb.sb_dblocks << mp->m_sb.sb_inopblog); - mp->m_ihsize = 1 << max_t(uint, 8, - (xfs_highbit64(icount) + 1) / 2); - mp->m_ihsize = min_t(uint, mp->m_ihsize, - (64 * NBPP) / sizeof(xfs_ihash_t)); - } - - while (!(mp->m_ihash = (xfs_ihash_t *)kmem_zalloc(mp->m_ihsize * - sizeof(xfs_ihash_t), flags))) { - if ((mp->m_ihsize >>= 1) <= NBPP) - flags = KM_SLEEP; - } - for (i = 0; i < mp->m_ihsize; i++) { - rwlock_init(&(mp->m_ihash[i].ih_lock)); - } -} - -/* - * Free up structures allocated by xfs_ihash_init, at unmount time. - */ -void -xfs_ihash_free(xfs_mount_t *mp) -{ - kmem_free(mp->m_ihash, mp->m_ihsize*sizeof(xfs_ihash_t)); - mp->m_ihash = NULL; -} - -/* - * Initialize the inode cluster hash table for the newly mounted file system. - * Its size is derived from the ihash table size. - */ -void -xfs_chash_init(xfs_mount_t *mp) -{ - uint i; - - mp->m_chsize = max_t(uint, 1, mp->m_ihsize / - (XFS_INODE_CLUSTER_SIZE(mp) >> mp->m_sb.sb_inodelog)); - mp->m_chsize = min_t(uint, mp->m_chsize, mp->m_ihsize); - mp->m_chash = (xfs_chash_t *)kmem_zalloc(mp->m_chsize - * sizeof(xfs_chash_t), - KM_SLEEP); - for (i = 0; i < mp->m_chsize; i++) { - spinlock_init(&mp->m_chash[i].ch_lock,"xfshash"); - } -} - -/* - * Free up structures allocated by xfs_chash_init, at unmount time. - */ -void -xfs_chash_free(xfs_mount_t *mp) -{ - int i; - - for (i = 0; i < mp->m_chsize; i++) { - spinlock_destroy(&mp->m_chash[i].ch_lock); - } - - kmem_free(mp->m_chash, mp->m_chsize*sizeof(xfs_chash_t)); - mp->m_chash = NULL; -} - -/* - * Try to move an inode to the front of its hash list if possible - * (and if its not there already). Called right after obtaining - * the list version number and then dropping the read_lock on the - * hash list in question (which is done right after looking up the - * inode in question...). - */ -STATIC void -xfs_ihash_promote( - xfs_ihash_t *ih, - xfs_inode_t *ip, - ulong version) -{ - xfs_inode_t *iq; - - if ((ip->i_prevp != &ih->ih_next) && write_trylock(&ih->ih_lock)) { - if (likely(version == ih->ih_version)) { - /* remove from list */ - if ((iq = ip->i_next)) { - iq->i_prevp = ip->i_prevp; - } - *ip->i_prevp = iq; - - /* insert at list head */ - iq = ih->ih_next; - iq->i_prevp = &ip->i_next; - ip->i_next = iq; - ip->i_prevp = &ih->ih_next; - ih->ih_next = ip; - } - write_unlock(&ih->ih_lock); - } -} - -/* - * Look up an inode by number in the given file system. - * The inode is looked up in the hash table for the file system - * represented by the mount point parameter mp. Each bucket of - * the hash table is guarded by an individual semaphore. - * - * If the inode is found in the hash table, its corresponding vnode - * is obtained with a call to vn_get(). This call takes care of - * coordination with the reclamation of the inode and vnode. Note - * that the vmap structure is filled in while holding the hash lock. - * This gives us the state of the inode/vnode when we found it and - * is used for coordination in vn_get(). - * - * If it is not in core, read it in from the file system's device and - * add the inode into the hash table. - * - * The inode is locked according to the value of the lock_flags parameter. - * This flag parameter indicates how and if the inode's IO lock and inode lock - * should be taken. - * - * mp -- the mount point structure for the current file system. It points - * to the inode hash table. - * tp -- a pointer to the current transaction if there is one. This is - * simply passed through to the xfs_iread() call. - * ino -- the number of the inode desired. This is the unique identifier - * within the file system for the inode being requested. - * lock_flags -- flags indicating how to lock the inode. See the comment - * for xfs_ilock() for a list of valid values. - * bno -- the block number starting the buffer containing the inode, - * if known (as by bulkstat), else 0. - */ -#ifdef RMC -STATIC int -xfs_iget_core( - xfs_vnode_t *vp, - xfs_mount_t *mp, - xfs_trans_t *tp, - xfs_ino_t ino, - uint flags, - uint lock_flags, - xfs_inode_t **ipp, - xfs_daddr_t bno) -{ - xfs_ihash_t *ih; - xfs_inode_t *ip; - xfs_inode_t *iq; - xfs_vnode_t *inode_vp; - ulong version; - int error; - /* REFERENCED */ - xfs_chash_t *ch; - xfs_chashlist_t *chl, *chlnew; - SPLDECL(s); - - - ih = XFS_IHASH(mp, ino); - -again: - read_lock(&ih->ih_lock); - - for (ip = ih->ih_next; ip != NULL; ip = ip->i_next) { - if (ip->i_ino == ino) { - /* - * If INEW is set this inode is being set up - * we need to pause and try again. - */ - if (ip->i_flags & XFS_INEW) { - read_unlock(&ih->ih_lock); - delay(1); - XFS_STATS_INC(xs_ig_frecycle); - - goto again; - } - - inode_vp = XFS_ITOV_NULL(ip); - if (inode_vp == NULL) { - /* - * If IRECLAIM is set this inode is - * on its way out of the system, - * we need to pause and try again. - */ - if (ip->i_flags & XFS_IRECLAIM) { - read_unlock(&ih->ih_lock); - delay(1); - XFS_STATS_INC(xs_ig_frecycle); - - goto again; - } - - vn_trace_exit(vp, "xfs_iget.alloc", - (inst_t *)__return_address); - - XFS_STATS_INC(xs_ig_found); - - ip->i_flags &= ~XFS_IRECLAIMABLE; - version = ih->ih_version; - read_unlock(&ih->ih_lock); - xfs_ihash_promote(ih, ip, version); - -#ifdef RMC - XFS_MOUNT_ILOCK(mp); - list_del_init(&ip->i_reclaim); - XFS_MOUNT_IUNLOCK(mp); -#endif - - goto finish_inode; - - } else if (vp != inode_vp) { -#ifdef RMC - struct inode *inode = vn_to_inode(inode_vp); - - /* The inode is being torn down, pause and - * try again. - */ - if (inode->i_state & (I_FREEING | I_CLEAR)) { - read_unlock(&ih->ih_lock); - delay(1); - XFS_STATS_INC(xs_ig_frecycle); - - goto again; - } -#endif -/* Chances are the other vnode (the one in the inode) is being torn - * down right now, and we landed on top of it. Question is, what do - * we do? Unhook the old inode and hook up the new one? - */ - cmn_err(CE_PANIC, - "xfs_iget_core: ambiguous vns: vp/0x%p, invp/0x%p", - inode_vp, vp); - } - - /* - * Inode cache hit: if ip is not at the front of - * its hash chain, move it there now. - * Do this with the lock held for update, but - * do statistics after releasing the lock. - */ - version = ih->ih_version; - read_unlock(&ih->ih_lock); - xfs_ihash_promote(ih, ip, version); - XFS_STATS_INC(xs_ig_found); - -finish_inode: - if (ip->i_d.di_mode == 0) { - if (!(flags & IGET_CREATE)) - return ENOENT; - xfs_iocore_inode_reinit(ip); - } - - if (lock_flags != 0) - xfs_ilock(ip, lock_flags); - - ip->i_flags &= ~XFS_ISTALE; - - vn_trace_exit(vp, "xfs_iget.found", - (inst_t *)__return_address); - goto return_ip; - } - } - - /* - * Inode cache miss: save the hash chain version stamp and unlock - * the chain, so we don't deadlock in vn_alloc. - */ - XFS_STATS_INC(xs_ig_missed); - - version = ih->ih_version; - - read_unlock(&ih->ih_lock); - - /* - * Read the disk inode attributes into a new inode structure and get - * a new vnode for it. This should also initialize i_ino and i_mount. - */ - error = xfs_iread(mp, tp, ino, &ip, bno); - if (error) { - return error; - } - - vn_trace_exit(vp, "xfs_iget.alloc", (inst_t *)__return_address); - - xfs_inode_lock_init(ip, vp); - xfs_iocore_inode_init(ip); - - if (lock_flags != 0) { - xfs_ilock(ip, lock_flags); - } - - if ((ip->i_d.di_mode == 0) && !(flags & IGET_CREATE)) { - xfs_idestroy(ip); - return ENOENT; - } - - /* - * Put ip on its hash chain, unless someone else hashed a duplicate - * after we released the hash lock. - */ - write_lock(&ih->ih_lock); - - if (ih->ih_version != version) { - for (iq = ih->ih_next; iq != NULL; iq = iq->i_next) { - if (iq->i_ino == ino) { - write_unlock(&ih->ih_lock); - xfs_idestroy(ip); - - XFS_STATS_INC(xs_ig_dup); - goto again; - } - } - } - - /* - * These values _must_ be set before releasing ihlock! - */ - ip->i_hash = ih; - if ((iq = ih->ih_next)) { - iq->i_prevp = &ip->i_next; - } - ip->i_next = iq; - ip->i_prevp = &ih->ih_next; - ih->ih_next = ip; - ip->i_udquot = ip->i_gdquot = NULL; - ih->ih_version++; - ip->i_flags |= XFS_INEW; - - write_unlock(&ih->ih_lock); - - /* - * put ip on its cluster's hash chain - */ - ASSERT(ip->i_chash == NULL && ip->i_cprev == NULL && - ip->i_cnext == NULL); - - chlnew = NULL; - ch = XFS_CHASH(mp, ip->i_blkno); - chlredo: - s = mutex_spinlock(&ch->ch_lock); - for (chl = ch->ch_list; chl != NULL; chl = chl->chl_next) { - if (chl->chl_blkno == ip->i_blkno) { - - /* insert this inode into the doubly-linked list - * where chl points */ - if ((iq = chl->chl_ip)) { - ip->i_cprev = iq->i_cprev; - iq->i_cprev->i_cnext = ip; - iq->i_cprev = ip; - ip->i_cnext = iq; - } else { - ip->i_cnext = ip; - ip->i_cprev = ip; - } - chl->chl_ip = ip; - ip->i_chash = chl; - break; - } - } - - /* no hash list found for this block; add a new hash list */ - if (chl == NULL) { - if (chlnew == NULL) { - mutex_spinunlock(&ch->ch_lock, s); - ASSERT(xfs_chashlist_zone != NULL); - chlnew = (xfs_chashlist_t *) - kmem_zone_alloc(xfs_chashlist_zone, - KM_SLEEP); - ASSERT(chlnew != NULL); - goto chlredo; - } else { - ip->i_cnext = ip; - ip->i_cprev = ip; - ip->i_chash = chlnew; - chlnew->chl_ip = ip; - chlnew->chl_blkno = ip->i_blkno; - if (ch->ch_list) - ch->ch_list->chl_prev = chlnew; - chlnew->chl_next = ch->ch_list; - chlnew->chl_prev = NULL; - ch->ch_list = chlnew; - chlnew = NULL; - } - } else { - if (chlnew != NULL) { - kmem_zone_free(xfs_chashlist_zone, chlnew); - } - } - - mutex_spinunlock(&ch->ch_lock, s); - - - /* - * Link ip to its mount and thread it on the mount's inode list. - */ - XFS_MOUNT_ILOCK(mp); - if ((iq = mp->m_inodes)) { - ASSERT(iq->i_mprev->i_mnext == iq); - ip->i_mprev = iq->i_mprev; - iq->i_mprev->i_mnext = ip; - iq->i_mprev = ip; - ip->i_mnext = iq; - } else { - ip->i_mnext = ip; - ip->i_mprev = ip; - } - mp->m_inodes = ip; - - XFS_MOUNT_IUNLOCK(mp); - - return_ip: - ASSERT(ip->i_df.if_ext_max == - XFS_IFORK_DSIZE(ip) / sizeof(xfs_bmbt_rec_t)); - - ASSERT(((ip->i_d.di_flags & XFS_DIFLAG_REALTIME) != 0) == - ((ip->i_iocore.io_flags & XFS_IOCORE_RT) != 0)); - - *ipp = ip; - - /* - * If we have a real type for an on-disk inode, we can set ops(&unlock) - * now. If it's a new inode being created, xfs_ialloc will handle it. - */ - XVFS_INIT_VNODE(XFS_MTOVFS(mp), vp, XFS_ITOBHV(ip), 1); - - return 0; -} -#endif - -#ifdef RMC -/* - * The 'normal' internal xfs_iget, if needed it will - * 'allocate', or 'get', the vnode. - */ -int -xfs_iget( - xfs_mount_t *mp, - xfs_trans_t *tp, - xfs_ino_t ino, - uint flags, - uint lock_flags, - xfs_inode_t **ipp, - xfs_daddr_t bno) -{ - int error; - struct inode *inode; - xfs_vnode_t *vp = NULL; - - XFS_STATS_INC(xs_ig_attempts); - -retry: - if ((inode = VFS_GET_INODE(XFS_MTOVFS(mp), ino, 0))) { - xfs_inode_t *ip; - - vp = vn_from_inode(inode); - if (inode->i_state & I_NEW) { - vn_initialize(inode); - error = xfs_iget_core(vp, mp, tp, ino, flags, - lock_flags, ipp, bno); - if (error) { - vn_mark_bad(vp); - if (inode->i_state & I_NEW) - unlock_new_inode(inode); - iput(inode); - } - } else { - /* - * If the inode is not fully constructed due to - * filehandle mismatches wait for the inode to go - * away and try again. - * - * iget_locked will call __wait_on_freeing_inode - * to wait for the inode to go away. - */ - if (is_bad_inode(inode) || - ((ip = xfs_vtoi(vp)) == NULL)) { - iput(inode); - delay(1); - goto retry; - } - - if (lock_flags != 0) - xfs_ilock(ip, lock_flags); - XFS_STATS_INC(xs_ig_found); - *ipp = ip; - error = 0; - } - } else - error = ENOMEM; /* If we got no inode we are out of memory */ - - return error; -} -#endif - -/* - * Do the setup for the various locks within the incore inode. - */ -void -xfs_inode_lock_init( - xfs_inode_t *ip, - xfs_vnode_t *vp) -{ - mrlock_init(&ip->i_lock, MRLOCK_ALLOW_EQUAL_PRI|MRLOCK_BARRIER, - "xfsino", (long)vp->v_number); - mrlock_init(&ip->i_iolock, MRLOCK_BARRIER, "xfsio", vp->v_number); -#ifdef RMC - init_waitqueue_head(&ip->i_ipin_wait); -#endif - atomic_set(&ip->i_pincount, 0); - init_sema(&ip->i_flock, 1, "xfsfino", vp->v_number); -} - -/* - * Look for the inode corresponding to the given ino in the hash table. - * If it is there and its i_transp pointer matches tp, return it. - * Otherwise, return NULL. - */ -xfs_inode_t * -xfs_inode_incore(xfs_mount_t *mp, - xfs_ino_t ino, - xfs_trans_t *tp) -{ - xfs_ihash_t *ih; - xfs_inode_t *ip; - ulong version; - - ih = XFS_IHASH(mp, ino); - read_lock(&ih->ih_lock); - for (ip = ih->ih_next; ip != NULL; ip = ip->i_next) { - if (ip->i_ino == ino) { - /* - * If we find it and tp matches, return it. - * Also move it to the front of the hash list - * if we find it and it is not already there. - * Otherwise break from the loop and return - * NULL. - */ - if (ip->i_transp == tp) { - version = ih->ih_version; - read_unlock(&ih->ih_lock); - xfs_ihash_promote(ih, ip, version); - return (ip); - } - break; - } - } - read_unlock(&ih->ih_lock); - return (NULL); -} - -/* - * Decrement reference count of an inode structure and unlock it. - * - * ip -- the inode being released - * lock_flags -- this parameter indicates the inode's locks to be - * to be released. See the comment on xfs_iunlock() for a list - * of valid values. - */ -void -xfs_iput(xfs_inode_t *ip, - uint lock_flags) -{ - xfs_vnode_t *vp = XFS_ITOV(ip); - - vn_trace_entry(vp, "xfs_iput", (inst_t *)__return_address); - - xfs_iunlock(ip, lock_flags); - - VN_RELE(vp); -} - -#ifdef RMC -/* in xfs_freebsd_iget.c - * Special iput for brand-new inodes that are still locked - */ -void -xfs_iput_new(xfs_inode_t *ip, - uint lock_flags) -{ - xfs_vnode_t *vp = XFS_ITOV(ip); - struct inode *inode = vn_to_inode(vp); - - vn_trace_entry(vp, "xfs_iput_new", (inst_t *)__return_address); - - if ((ip->i_d.di_mode == 0)) { - ASSERT(!(ip->i_flags & XFS_IRECLAIMABLE)); - vn_mark_bad(vp); - } - if (inode->i_state & I_NEW) - unlock_new_inode(inode); - if (lock_flags) - xfs_iunlock(ip, lock_flags); - VN_RELE(vp); -} -#endif - - -/* - * This routine embodies the part of the reclaim code that pulls - * the inode from the inode hash table and the mount structure's - * inode list. - * This should only be called from xfs_reclaim(). - */ -void -xfs_ireclaim( - xfs_inode_t *ip) -{ - xfs_vnode_t *vp; - - /* - * Remove from old hash list and mount list. - */ - XFS_STATS_INC(xs_ig_reclaims); - - xfs_iextract(ip); - - /* - * Here we do a spurious inode lock in order to coordinate with - * xfs_sync(). This is because xfs_sync() references the inodes - * in the mount list without taking references on the corresponding - * vnodes. We make that OK here by ensuring that we wait until - * the inode is unlocked in xfs_sync() before we go ahead and - * free it. We get both the regular lock and the io lock because - * the xfs_sync() code may need to drop the regular one but will - * still hold the io lock. - */ - xfs_ilock(ip, XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL); - - /* - * Release dquots (and their references) if any. An inode may escape - * xfs_inactive and get here via vn_alloc->vn_reclaim path. - */ - XFS_QM_DQDETACH(ip->i_mount, ip); - - /* - * Pull our behavior descriptor from the vnode chain. - */ - vp = XFS_ITOV_NULL(ip); - if (vp) { - vn_bhv_remove(VN_BHV_HEAD(vp), XFS_ITOBHV(ip)); - } - - /* - * Free all memory associated with the inode. - */ - xfs_idestroy(ip); -} - -/* - * This routine removes an about-to-be-destroyed inode from - * all of the lists in which it is located with the exception - * of the behavior chain. - */ -void -xfs_iextract( - xfs_inode_t *ip) -{ - xfs_ihash_t *ih; - xfs_inode_t *iq; - xfs_mount_t *mp; - xfs_chash_t *ch; - xfs_chashlist_t *chl, *chm; - SPLDECL(s); - - ih = ip->i_hash; - write_lock(&ih->ih_lock); - if ((iq = ip->i_next)) { - iq->i_prevp = ip->i_prevp; - } - *ip->i_prevp = iq; - ih->ih_version++; - write_unlock(&ih->ih_lock); - - /* - * Remove from cluster hash list - * 1) delete the chashlist if this is the last inode on the chashlist - * 2) unchain from list of inodes - * 3) point chashlist->chl_ip to 'chl_next' if to this inode. - */ - mp = ip->i_mount; - ch = XFS_CHASH(mp, ip->i_blkno); - s = mutex_spinlock(&ch->ch_lock); - - if (ip->i_cnext == ip) { - /* Last inode on chashlist */ - ASSERT(ip->i_cnext == ip && ip->i_cprev == ip); - ASSERT(ip->i_chash != NULL); - chm=NULL; - chl = ip->i_chash; - if (chl->chl_prev) - chl->chl_prev->chl_next = chl->chl_next; - else - ch->ch_list = chl->chl_next; - if (chl->chl_next) - chl->chl_next->chl_prev = chl->chl_prev; - kmem_zone_free(xfs_chashlist_zone, chl); - } else { - /* delete one inode from a non-empty list */ - iq = ip->i_cnext; - iq->i_cprev = ip->i_cprev; - ip->i_cprev->i_cnext = iq; - if (ip->i_chash->chl_ip == ip) { - ip->i_chash->chl_ip = iq; - } - ip->i_chash = __return_address; - ip->i_cprev = __return_address; - ip->i_cnext = __return_address; - } - mutex_spinunlock(&ch->ch_lock, s); - - /* - * Remove from mount's inode list. - */ - XFS_MOUNT_ILOCK(mp); - ASSERT((ip->i_mnext != NULL) && (ip->i_mprev != NULL)); - iq = ip->i_mnext; - iq->i_mprev = ip->i_mprev; - ip->i_mprev->i_mnext = iq; - - /* - * Fix up the head pointer if it points to the inode being deleted. - */ - if (mp->m_inodes == ip) { - if (ip == iq) { - mp->m_inodes = NULL; - } else { - mp->m_inodes = iq; - } - } - - /* Deal with the deleted inodes list */ -#ifdef RMC - list_del_init(&ip->i_reclaim); -#endif - - mp->m_ireclaims++; - XFS_MOUNT_IUNLOCK(mp); -} - -/* - * This is a wrapper routine around the xfs_ilock() routine - * used to centralize some grungy code. It is used in places - * that wish to lock the inode solely for reading the extents. - * The reason these places can't just call xfs_ilock(SHARED) - * is that the inode lock also guards to bringing in of the - * extents from disk for a file in b-tree format. If the inode - * is in b-tree format, then we need to lock the inode exclusively - * until the extents are read in. Locking it exclusively all - * the time would limit our parallelism unnecessarily, though. - * What we do instead is check to see if the extents have been - * read in yet, and only lock the inode exclusively if they - * have not. - * - * The function returns a value which should be given to the - * corresponding xfs_iunlock_map_shared(). This value is - * the mode in which the lock was actually taken. - */ -uint -xfs_ilock_map_shared( - xfs_inode_t *ip) -{ - uint lock_mode; - - if ((ip->i_d.di_format == XFS_DINODE_FMT_BTREE) && - ((ip->i_df.if_flags & XFS_IFEXTENTS) == 0)) { - lock_mode = XFS_ILOCK_EXCL; - } else { - lock_mode = XFS_ILOCK_SHARED; - } - - xfs_ilock(ip, lock_mode); - - return lock_mode; -} - -/* - * This is simply the unlock routine to go with xfs_ilock_map_shared(). - * All it does is call xfs_iunlock() with the given lock_mode. - */ -void -xfs_iunlock_map_shared( - xfs_inode_t *ip, - unsigned int lock_mode) -{ - xfs_iunlock(ip, lock_mode); -} - -/* - * The xfs inode contains 2 locks: a multi-reader lock called the - * i_iolock and a multi-reader lock called the i_lock. This routine - * allows either or both of the locks to be obtained. - * - * The 2 locks should always be ordered so that the IO lock is - * obtained first in order to prevent deadlock. - * - * ip -- the inode being locked - * lock_flags -- this parameter indicates the inode's locks - * to be locked. It can be: - * XFS_IOLOCK_SHARED, - * XFS_IOLOCK_EXCL, - * XFS_ILOCK_SHARED, - * XFS_ILOCK_EXCL, - * XFS_IOLOCK_SHARED | XFS_ILOCK_SHARED, - * XFS_IOLOCK_SHARED | XFS_ILOCK_EXCL, - * XFS_IOLOCK_EXCL | XFS_ILOCK_SHARED, - * XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL - */ -void -xfs_ilock(xfs_inode_t *ip, - uint lock_flags) -{ - /* - * You can't set both SHARED and EXCL for the same lock, - * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED, - * and XFS_ILOCK_EXCL are valid values to set in lock_flags. - */ - ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) != - (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)); - ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) != - (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)); - ASSERT((lock_flags & ~XFS_LOCK_MASK) == 0); - - if (lock_flags & XFS_IOLOCK_EXCL) { - mrupdate(&ip->i_iolock); - } else if (lock_flags & XFS_IOLOCK_SHARED) { - mraccess(&ip->i_iolock); - } - if (lock_flags & XFS_ILOCK_EXCL) { - mrupdate(&ip->i_lock); - } else if (lock_flags & XFS_ILOCK_SHARED) { - mraccess(&ip->i_lock); - } - xfs_ilock_trace(ip, 1, lock_flags, (inst_t *)__return_address); -} - -/* - * This is just like xfs_ilock(), except that the caller - * is guaranteed not to sleep. It returns 1 if it gets - * the requested locks and 0 otherwise. If the IO lock is - * obtained but the inode lock cannot be, then the IO lock - * is dropped before returning. - * - * ip -- the inode being locked - * lock_flags -- this parameter indicates the inode's locks to be - * to be locked. See the comment for xfs_ilock() for a list - * of valid values. - * - */ -int -xfs_ilock_nowait(xfs_inode_t *ip, - uint lock_flags) -{ - int iolocked; - int ilocked; - - /* - * You can't set both SHARED and EXCL for the same lock, - * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED, - * and XFS_ILOCK_EXCL are valid values to set in lock_flags. - */ - ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) != - (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)); - ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) != - (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)); - ASSERT((lock_flags & ~XFS_LOCK_MASK) == 0); - - iolocked = 0; - if (lock_flags & XFS_IOLOCK_EXCL) { - iolocked = mrtryupdate(&ip->i_iolock); - if (!iolocked) { - return 0; - } - } else if (lock_flags & XFS_IOLOCK_SHARED) { - iolocked = mrtryaccess(&ip->i_iolock); - if (!iolocked) { - return 0; - } - } - if (lock_flags & XFS_ILOCK_EXCL) { - ilocked = mrtryupdate(&ip->i_lock); - if (!ilocked) { - if (iolocked) { - mrunlock(&ip->i_iolock); - } - return 0; - } - } else if (lock_flags & XFS_ILOCK_SHARED) { - ilocked = mrtryaccess(&ip->i_lock); - if (!ilocked) { - if (iolocked) { - mrunlock(&ip->i_iolock); - } - return 0; - } - } - xfs_ilock_trace(ip, 2, lock_flags, (inst_t *)__return_address); - return 1; -} - -/* - * xfs_iunlock() is used to drop the inode locks acquired with - * xfs_ilock() and xfs_ilock_nowait(). The caller must pass - * in the flags given to xfs_ilock() or xfs_ilock_nowait() so - * that we know which locks to drop. - * - * ip -- the inode being unlocked - * lock_flags -- this parameter indicates the inode's locks to be - * to be unlocked. See the comment for xfs_ilock() for a list - * of valid values for this parameter. - * - */ -void -xfs_iunlock(xfs_inode_t *ip, - uint lock_flags) -{ - /* - * You can't set both SHARED and EXCL for the same lock, - * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED, - * and XFS_ILOCK_EXCL are valid values to set in lock_flags. - */ - ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) != - (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)); - ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) != - (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)); - ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_IUNLOCK_NONOTIFY)) == 0); - ASSERT(lock_flags != 0); - - if (lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) { - ASSERT(!(lock_flags & XFS_IOLOCK_SHARED) || - (ismrlocked(&ip->i_iolock, MR_ACCESS))); - ASSERT(!(lock_flags & XFS_IOLOCK_EXCL) || - (ismrlocked(&ip->i_iolock, MR_UPDATE))); - mrunlock(&ip->i_iolock); - } - - if (lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) { - ASSERT(!(lock_flags & XFS_ILOCK_SHARED) || - (ismrlocked(&ip->i_lock, MR_ACCESS))); - ASSERT(!(lock_flags & XFS_ILOCK_EXCL) || - (ismrlocked(&ip->i_lock, MR_UPDATE))); - mrunlock(&ip->i_lock); - - /* - * Let the AIL know that this item has been unlocked in case - * it is in the AIL and anyone is waiting on it. Don't do - * this if the caller has asked us not to. - */ - if (!(lock_flags & XFS_IUNLOCK_NONOTIFY) && - ip->i_itemp != NULL) { - xfs_trans_unlocked_item(ip->i_mount, - (xfs_log_item_t*)(ip->i_itemp)); - } - } - xfs_ilock_trace(ip, 3, lock_flags, (inst_t *)__return_address); -} - -/* - * give up write locks. the i/o lock cannot be held nested - * if it is being demoted. - */ -void -xfs_ilock_demote(xfs_inode_t *ip, - uint lock_flags) -{ - ASSERT(lock_flags & (XFS_IOLOCK_EXCL|XFS_ILOCK_EXCL)); - ASSERT((lock_flags & ~(XFS_IOLOCK_EXCL|XFS_ILOCK_EXCL)) == 0); - - if (lock_flags & XFS_ILOCK_EXCL) { - ASSERT(ismrlocked(&ip->i_lock, MR_UPDATE)); - mrdemote(&ip->i_lock); - } - if (lock_flags & XFS_IOLOCK_EXCL) { - ASSERT(ismrlocked(&ip->i_iolock, MR_UPDATE)); - mrdemote(&ip->i_iolock); - } -} - -/* - * The following three routines simply manage the i_flock - * semaphore embedded in the inode. This semaphore synchronizes - * processes attempting to flush the in-core inode back to disk. - */ -void -xfs_iflock(xfs_inode_t *ip) -{ - psema(&(ip->i_flock), PINOD|PLTWAIT); -} - -int -xfs_iflock_nowait(xfs_inode_t *ip) -{ - return (cpsema(&(ip->i_flock))); -} - -void -xfs_ifunlock(xfs_inode_t *ip) -{ - ASSERT(valusema(&(ip->i_flock)) <= 0); - vsema(&(ip->i_flock)); -} |
