| /* |
| * 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_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_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" |
| |
| /* |
| * Look up an inode by number in the given file system. |
| * The inode is looked up in the cache held in each AG. |
| * If the inode is found in the cache, attach it to the provided |
| * vnode. |
| * |
| * If it is not in core, read it in from the file system's device, |
| * add it to the cache and attach the provided vnode. |
| * |
| * 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. |
| */ |
| STATIC int |
| xfs_iget_core( |
| bhv_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_inode_t *ip; |
| xfs_inode_t *iq; |
| bhv_vnode_t *inode_vp; |
| int error; |
| xfs_icluster_t *icl, *new_icl = NULL; |
| unsigned long first_index, mask; |
| xfs_perag_t *pag; |
| xfs_agino_t agino; |
| |
| /* the radix tree exists only in inode capable AGs */ |
| if (XFS_INO_TO_AGNO(mp, ino) >= mp->m_maxagi) |
| return EINVAL; |
| |
| /* get the perag structure and ensure that it's inode capable */ |
| pag = xfs_get_perag(mp, ino); |
| if (!pag->pagi_inodeok) |
| return EINVAL; |
| ASSERT(pag->pag_ici_init); |
| agino = XFS_INO_TO_AGINO(mp, ino); |
| |
| again: |
| read_lock(&pag->pag_ici_lock); |
| ip = radix_tree_lookup(&pag->pag_ici_root, agino); |
| |
| if (ip != NULL) { |
| /* |
| * If INEW is set this inode is being set up |
| * we need to pause and try again. |
| */ |
| if (xfs_iflags_test(ip, XFS_INEW)) { |
| read_unlock(&pag->pag_ici_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 (xfs_iflags_test(ip, XFS_IRECLAIM)) { |
| read_unlock(&pag->pag_ici_lock); |
| delay(1); |
| XFS_STATS_INC(xs_ig_frecycle); |
| |
| goto again; |
| } |
| ASSERT(xfs_iflags_test(ip, XFS_IRECLAIMABLE)); |
| |
| /* |
| * If lookup is racing with unlink, then we |
| * should return an error immediately so we |
| * don't remove it from the reclaim list and |
| * potentially leak the inode. |
| */ |
| if ((ip->i_d.di_mode == 0) && |
| !(flags & XFS_IGET_CREATE)) { |
| read_unlock(&pag->pag_ici_lock); |
| xfs_put_perag(mp, pag); |
| return ENOENT; |
| } |
| |
| /* |
| * There may be transactions sitting in the |
| * incore log buffers or being flushed to disk |
| * at this time. We can't clear the |
| * XFS_IRECLAIMABLE flag until these |
| * transactions have hit the disk, otherwise we |
| * will void the guarantee the flag provides |
| * xfs_iunpin() |
| */ |
| if (xfs_ipincount(ip)) { |
| read_unlock(&pag->pag_ici_lock); |
| xfs_log_force(mp, 0, |
| XFS_LOG_FORCE|XFS_LOG_SYNC); |
| XFS_STATS_INC(xs_ig_frecycle); |
| goto again; |
| } |
| |
| _xfs_itrace_exit(ip, "xfs_iget.alloc", |
| (inst_t *)__return_address); |
| |
| XFS_STATS_INC(xs_ig_found); |
| |
| xfs_iflags_clear(ip, XFS_IRECLAIMABLE); |
| read_unlock(&pag->pag_ici_lock); |
| |
| XFS_MOUNT_ILOCK(mp); |
| list_del_init(&ip->i_reclaim); |
| XFS_MOUNT_IUNLOCK(mp); |
| |
| goto finish_inode; |
| |
| } else if (vp != inode_vp) { |
| 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(&pag->pag_ici_lock); |
| delay(1); |
| XFS_STATS_INC(xs_ig_frecycle); |
| |
| goto again; |
| } |
| /* 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 |
| */ |
| read_unlock(&pag->pag_ici_lock); |
| XFS_STATS_INC(xs_ig_found); |
| |
| finish_inode: |
| if (ip->i_d.di_mode == 0) { |
| if (!(flags & XFS_IGET_CREATE)) { |
| xfs_put_perag(mp, pag); |
| return ENOENT; |
| } |
| xfs_iocore_inode_reinit(ip); |
| } |
| |
| if (lock_flags != 0) |
| xfs_ilock(ip, lock_flags); |
| |
| xfs_iflags_clear(ip, XFS_ISTALE); |
| _xfs_itrace_exit(ip, "xfs_iget.found", |
| (inst_t *)__return_address); |
| goto return_ip; |
| } |
| |
| /* |
| * Inode cache miss |
| */ |
| read_unlock(&pag->pag_ici_lock); |
| XFS_STATS_INC(xs_ig_missed); |
| |
| /* |
| * 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, |
| (flags & XFS_IGET_BULKSTAT) ? XFS_IMAP_BULKSTAT : 0); |
| if (error) { |
| xfs_put_perag(mp, pag); |
| return error; |
| } |
| |
| _xfs_itrace_exit(ip, "xfs_iget.alloc", (inst_t *)__return_address); |
| |
| xfs_inode_lock_init(ip, vp); |
| xfs_iocore_inode_init(ip); |
| if (lock_flags) |
| xfs_ilock(ip, lock_flags); |
| |
| if ((ip->i_d.di_mode == 0) && !(flags & XFS_IGET_CREATE)) { |
| xfs_idestroy(ip); |
| xfs_put_perag(mp, pag); |
| return ENOENT; |
| } |
| |
| /* |
| * This is a bit messy - we preallocate everything we _might_ |
| * need before we pick up the ici lock. That way we don't have to |
| * juggle locks and go all the way back to the start. |
| */ |
| new_icl = kmem_zone_alloc(xfs_icluster_zone, KM_SLEEP); |
| if (radix_tree_preload(GFP_KERNEL)) { |
| delay(1); |
| goto again; |
| } |
| mask = ~(((XFS_INODE_CLUSTER_SIZE(mp) >> mp->m_sb.sb_inodelog)) - 1); |
| first_index = agino & mask; |
| write_lock(&pag->pag_ici_lock); |
| |
| /* |
| * Find the cluster if it exists |
| */ |
| icl = NULL; |
| if (radix_tree_gang_lookup(&pag->pag_ici_root, (void**)&iq, |
| first_index, 1)) { |
| if ((XFS_INO_TO_AGINO(mp, iq->i_ino) & mask) == first_index) |
| icl = iq->i_cluster; |
| } |
| |
| /* |
| * insert the new inode |
| */ |
| error = radix_tree_insert(&pag->pag_ici_root, agino, ip); |
| if (unlikely(error)) { |
| BUG_ON(error != -EEXIST); |
| write_unlock(&pag->pag_ici_lock); |
| radix_tree_preload_end(); |
| xfs_idestroy(ip); |
| XFS_STATS_INC(xs_ig_dup); |
| goto again; |
| } |
| |
| /* |
| * These values _must_ be set before releasing ihlock! |
| */ |
| ip->i_udquot = ip->i_gdquot = NULL; |
| xfs_iflags_set(ip, XFS_INEW); |
| |
| ASSERT(ip->i_cluster == NULL); |
| |
| if (!icl) { |
| spin_lock_init(&new_icl->icl_lock); |
| INIT_HLIST_HEAD(&new_icl->icl_inodes); |
| icl = new_icl; |
| new_icl = NULL; |
| } else { |
| ASSERT(!hlist_empty(&icl->icl_inodes)); |
| } |
| spin_lock(&icl->icl_lock); |
| hlist_add_head(&ip->i_cnode, &icl->icl_inodes); |
| ip->i_cluster = icl; |
| spin_unlock(&icl->icl_lock); |
| |
| write_unlock(&pag->pag_ici_lock); |
| radix_tree_preload_end(); |
| if (new_icl) |
| kmem_zone_free(xfs_icluster_zone, new_icl); |
| |
| /* |
| * 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); |
| xfs_put_perag(mp, pag); |
| |
| 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)); |
| |
| xfs_iflags_set(ip, XFS_IMODIFIED); |
| *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. |
| */ |
| xfs_initialize_vnode(mp, vp, ip); |
| return 0; |
| } |
| |
| |
| /* |
| * 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) |
| { |
| struct inode *inode; |
| bhv_vnode_t *vp = NULL; |
| int error; |
| |
| XFS_STATS_INC(xs_ig_attempts); |
| |
| retry: |
| inode = iget_locked(mp->m_super, ino); |
| if (inode) { |
| 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; |
| } |
| |
| /* |
| * Do the setup for the various locks within the incore inode. |
| */ |
| void |
| xfs_inode_lock_init( |
| xfs_inode_t *ip, |
| bhv_vnode_t *vp) |
| { |
| mrlock_init(&ip->i_lock, MRLOCK_ALLOW_EQUAL_PRI|MRLOCK_BARRIER, |
| "xfsino", ip->i_ino); |
| mrlock_init(&ip->i_iolock, MRLOCK_BARRIER, "xfsio", ip->i_ino); |
| init_waitqueue_head(&ip->i_ipin_wait); |
| atomic_set(&ip->i_pincount, 0); |
| initnsema(&ip->i_flock, 1, "xfsfino"); |
| } |
| |
| /* |
| * 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_inode_t *ip; |
| xfs_perag_t *pag; |
| |
| pag = xfs_get_perag(mp, ino); |
| read_lock(&pag->pag_ici_lock); |
| ip = radix_tree_lookup(&pag->pag_ici_root, XFS_INO_TO_AGINO(mp, ino)); |
| read_unlock(&pag->pag_ici_lock); |
| xfs_put_perag(mp, pag); |
| |
| /* the returned inode must match the transaction */ |
| if (ip && (ip->i_transp != tp)) |
| return NULL; |
| return ip; |
| } |
| |
| /* |
| * 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) |
| { |
| bhv_vnode_t *vp = XFS_ITOV(ip); |
| |
| xfs_itrace_entry(ip); |
| xfs_iunlock(ip, lock_flags); |
| VN_RELE(vp); |
| } |
| |
| /* |
| * Special iput for brand-new inodes that are still locked |
| */ |
| void |
| xfs_iput_new(xfs_inode_t *ip, |
| uint lock_flags) |
| { |
| bhv_vnode_t *vp = XFS_ITOV(ip); |
| struct inode *inode = vn_to_inode(vp); |
| |
| xfs_itrace_entry(ip); |
| |
| if ((ip->i_d.di_mode == 0)) { |
| ASSERT(!xfs_iflags_test(ip, 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); |
| } |
| |
| |
| /* |
| * 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) |
| { |
| bhv_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_to_inode(vp)->i_private = NULL; |
| ip->i_vnode = NULL; |
| } |
| |
| /* |
| * Free all memory associated with the inode. |
| */ |
| xfs_iunlock(ip, XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL); |
| 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_mount_t *mp = ip->i_mount; |
| xfs_perag_t *pag = xfs_get_perag(mp, ip->i_ino); |
| xfs_inode_t *iq; |
| |
| write_lock(&pag->pag_ici_lock); |
| radix_tree_delete(&pag->pag_ici_root, XFS_INO_TO_AGINO(mp, ip->i_ino)); |
| write_unlock(&pag->pag_ici_lock); |
| xfs_put_perag(mp, pag); |
| |
| /* |
| * Remove from cluster list |
| */ |
| mp = ip->i_mount; |
| spin_lock(&ip->i_cluster->icl_lock); |
| hlist_del(&ip->i_cnode); |
| spin_unlock(&ip->i_cluster->icl_lock); |
| |
| /* was last inode in cluster? */ |
| if (hlist_empty(&ip->i_cluster->icl_inodes)) |
| kmem_zone_free(xfs_icluster_zone, ip->i_cluster); |
| |
| /* |
| * 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 */ |
| list_del_init(&ip->i_reclaim); |
| |
| 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 | XFS_LOCK_DEP_MASK)) == 0); |
| |
| if (lock_flags & XFS_IOLOCK_EXCL) { |
| mrupdate_nested(&ip->i_iolock, XFS_IOLOCK_DEP(lock_flags)); |
| } else if (lock_flags & XFS_IOLOCK_SHARED) { |
| mraccess_nested(&ip->i_iolock, XFS_IOLOCK_DEP(lock_flags)); |
| } |
| if (lock_flags & XFS_ILOCK_EXCL) { |
| mrupdate_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags)); |
| } else if (lock_flags & XFS_ILOCK_SHARED) { |
| mraccess_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags)); |
| } |
| 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 | XFS_LOCK_DEP_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 | |
| XFS_LOCK_DEP_MASK)) == 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(issemalocked(&(ip->i_flock))); |
| vsema(&(ip->i_flock)); |
| } |