X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=fs%2Finode.c;h=b3fe3039201fe1862f9bc0f1fedd2ac4b8b167db;hb=refs%2Fheads%2Fvserver;hp=6c213832c8cf908ccf94c65d9434115c8fe3c50d;hpb=a6d8dea2993ef90fb69b81372daa0b63f8aa940e;p=linux-2.6.git diff --git a/fs/inode.c b/fs/inode.c index 6c213832c..b3fe30392 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -4,7 +4,6 @@ * (C) 1997 Linus Torvalds */ -#include #include #include #include @@ -21,12 +20,13 @@ #include #include #include +#include +#include /* * This is needed for the following functions: * - inode_has_buffers * - invalidate_inode_buffers - * - fsync_bdev * - invalidate_bdev * * FIXME: remove all knowledge of the buffer layer from this file @@ -55,8 +55,8 @@ #define I_HASHBITS i_hash_shift #define I_HASHMASK i_hash_mask -static unsigned int i_hash_mask; -static unsigned int i_hash_shift; +static unsigned int i_hash_mask __read_mostly; +static unsigned int i_hash_shift __read_mostly; /* * Each inode can be on two separate lists. One is @@ -72,7 +72,7 @@ static unsigned int i_hash_shift; LIST_HEAD(inode_in_use); LIST_HEAD(inode_unused); -static struct hlist_head *inode_hashtable; +static struct hlist_head *inode_hashtable __read_mostly; /* * A simple spinlock to protect the list manipulations. @@ -83,46 +83,44 @@ static struct hlist_head *inode_hashtable; DEFINE_SPINLOCK(inode_lock); /* - * iprune_sem provides exclusion between the kswapd or try_to_free_pages + * iprune_mutex provides exclusion between the kswapd or try_to_free_pages * icache shrinking path, and the umount path. Without this exclusion, * by the time prune_icache calls iput for the inode whose pages it has * been invalidating, or by the time it calls clear_inode & destroy_inode * from its final dispose_list, the struct super_block they refer to * (for inode->i_sb->s_op) may already have been freed and reused. */ -DECLARE_MUTEX(iprune_sem); +static DEFINE_MUTEX(iprune_mutex); /* * Statistics gathering.. */ struct inodes_stat_t inodes_stat; -static kmem_cache_t * inode_cachep; +static struct kmem_cache * inode_cachep __read_mostly; static struct inode *alloc_inode(struct super_block *sb) { - static struct address_space_operations empty_aops; + static const struct address_space_operations empty_aops; static struct inode_operations empty_iops; - static struct file_operations empty_fops; + static const struct file_operations empty_fops; struct inode *inode; if (sb->s_op->alloc_inode) inode = sb->s_op->alloc_inode(sb); else - inode = (struct inode *) kmem_cache_alloc(inode_cachep, SLAB_KERNEL); + inode = (struct inode *) kmem_cache_alloc(inode_cachep, GFP_KERNEL); if (inode) { struct address_space * const mapping = &inode->i_data; inode->i_sb = sb; - // inode->i_dqh = dqhget(sb->s_dqh); /* essential because of inode slab reuse */ - inode->i_xid = 0; + inode->i_tag = 0; inode->i_blkbits = sb->s_blocksize_bits; inode->i_flags = 0; atomic_set(&inode->i_count, 1); - inode->i_sock = 0; inode->i_op = &empty_iops; inode->i_fop = &empty_fops; inode->i_nlink = 1; @@ -138,7 +136,6 @@ static struct inode *alloc_inode(struct super_block *sb) inode->i_bdev = NULL; inode->i_cdev = NULL; inode->i_rdev = 0; - inode->i_security = NULL; inode->dirtied_when = 0; if (security_inode_alloc(inode)) { if (inode->i_sb->s_op->destroy_inode) @@ -168,7 +165,7 @@ static struct inode *alloc_inode(struct super_block *sb) bdi = sb->s_bdev->bd_inode->i_mapping->backing_dev_info; mapping->backing_dev_info = bdi; } - memset(&inode->u, 0, sizeof(inode->u)); + inode->i_private = NULL; inode->i_mapping = mapping; } return inode; @@ -176,8 +173,7 @@ static struct inode *alloc_inode(struct super_block *sb) void destroy_inode(struct inode *inode) { - if (inode_has_buffers(inode)) - BUG(); + BUG_ON(inode_has_buffers(inode)); security_inode_free(inode); if (inode->i_sb->s_op->destroy_inode) inode->i_sb->s_op->destroy_inode(inode); @@ -197,10 +193,10 @@ void inode_init_once(struct inode *inode) INIT_HLIST_NODE(&inode->i_hash); INIT_LIST_HEAD(&inode->i_dentry); INIT_LIST_HEAD(&inode->i_devices); - sema_init(&inode->i_sem, 1); + mutex_init(&inode->i_mutex); init_rwsem(&inode->i_alloc_sem); INIT_RADIX_TREE(&inode->i_data.page_tree, GFP_ATOMIC); - spin_lock_init(&inode->i_data.tree_lock); + rwlock_init(&inode->i_data.tree_lock); spin_lock_init(&inode->i_data.i_mmap_lock); INIT_LIST_HEAD(&inode->i_data.private_list); spin_lock_init(&inode->i_data.private_lock); @@ -208,11 +204,15 @@ void inode_init_once(struct inode *inode) INIT_LIST_HEAD(&inode->i_data.i_mmap_nonlinear); spin_lock_init(&inode->i_lock); i_size_ordered_init(inode); +#ifdef CONFIG_INOTIFY + INIT_LIST_HEAD(&inode->inotify_watches); + mutex_init(&inode->inotify_mutex); +#endif } EXPORT_SYMBOL(inode_init_once); -static void init_once(void * foo, kmem_cache_t * cachep, unsigned long flags) +static void init_once(void * foo, struct kmem_cache * cachep, unsigned long flags) { struct inode * inode = (struct inode *) foo; @@ -251,19 +251,16 @@ void clear_inode(struct inode *inode) might_sleep(); invalidate_inode_buffers(inode); - if (inode->i_data.nrpages) - BUG(); - if (!(inode->i_state & I_FREEING)) - BUG(); - if (inode->i_state & I_CLEAR) - BUG(); + BUG_ON(inode->i_data.nrpages); + BUG_ON(!(inode->i_state & I_FREEING)); + BUG_ON(inode->i_state & I_CLEAR); wait_on_inode(inode); DQUOT_DROP(inode); if (inode->i_sb && inode->i_sb->s_op->clear_inode) inode->i_sb->s_op->clear_inode(inode); - if (inode->i_bdev) + if (S_ISBLK(inode->i_mode) && inode->i_bdev) bd_forget(inode); - if (inode->i_cdev) + if (S_ISCHR(inode->i_mode) && inode->i_cdev) cd_forget(inode); inode->i_state = I_CLEAR; } @@ -290,6 +287,13 @@ static void dispose_list(struct list_head *head) if (inode->i_data.nrpages) truncate_inode_pages(&inode->i_data, 0); clear_inode(inode); + + spin_lock(&inode_lock); + hlist_del_init(&inode->i_hash); + list_del_init(&inode->i_sb_list); + spin_unlock(&inode_lock); + + wake_up_inode(inode); destroy_inode(inode); nr_disposed++; } @@ -314,7 +318,7 @@ static int invalidate_list(struct list_head *head, struct list_head *dispose) /* * We can reschedule here without worrying about the list's * consistency because the per-sb list of inodes must not - * change during umount anymore, and because iprune_sem keeps + * change during umount anymore, and because iprune_mutex keeps * shrink_icache_memory() away. */ cond_resched_lock(&inode_lock); @@ -325,8 +329,6 @@ static int invalidate_list(struct list_head *head, struct list_head *dispose) inode = list_entry(tmp, struct inode, i_sb_list); invalidate_inode_buffers(inode); if (!atomic_read(&inode->i_count)) { - hlist_del_init(&inode->i_hash); - list_del(&inode->i_sb_list); list_move(&inode->i_list, dispose); inode->i_state |= I_FREEING; count++; @@ -339,14 +341,6 @@ static int invalidate_list(struct list_head *head, struct list_head *dispose) return busy; } -/* - * This is a two-stage process. First we collect all - * offending inodes onto the throw-away list, and in - * the second stage we actually dispose of them. This - * is because we don't want to sleep while messing - * with the global lists.. - */ - /** * invalidate_inodes - discard the inodes on a device * @sb: superblock @@ -360,45 +354,19 @@ int invalidate_inodes(struct super_block * sb) int busy; LIST_HEAD(throw_away); - down(&iprune_sem); + mutex_lock(&iprune_mutex); spin_lock(&inode_lock); + inotify_unmount_inodes(&sb->s_inodes); busy = invalidate_list(&sb->s_inodes, &throw_away); spin_unlock(&inode_lock); dispose_list(&throw_away); - up(&iprune_sem); + mutex_unlock(&iprune_mutex); return busy; } EXPORT_SYMBOL(invalidate_inodes); - -int __invalidate_device(struct block_device *bdev, int do_sync) -{ - struct super_block *sb; - int res; - - if (do_sync) - fsync_bdev(bdev); - - res = 0; - sb = get_super(bdev); - if (sb) { - /* - * no need to lock the super, get_super holds the - * read semaphore so the filesystem cannot go away - * under us (->put_super runs with the write lock - * hold). - */ - shrink_dcache_sb(sb); - res = invalidate_inodes(sb); - drop_super(sb); - } - invalidate_bdev(bdev, 0); - return res; -} - -EXPORT_SYMBOL(__invalidate_device); static int can_unuse(struct inode *inode) { @@ -433,7 +401,7 @@ static void prune_icache(int nr_to_scan) int nr_scanned; unsigned long reap = 0; - down(&iprune_sem); + mutex_lock(&iprune_mutex); spin_lock(&inode_lock); for (nr_scanned = 0; nr_scanned < nr_to_scan; nr_scanned++) { struct inode *inode; @@ -461,22 +429,19 @@ static void prune_icache(int nr_to_scan) if (!can_unuse(inode)) continue; } - hlist_del_init(&inode->i_hash); - list_del_init(&inode->i_sb_list); list_move(&inode->i_list, &freeable); inode->i_state |= I_FREEING; nr_pruned++; } inodes_stat.nr_unused -= nr_pruned; + if (current_is_kswapd()) + __count_vm_events(KSWAPD_INODESTEAL, reap); + else + __count_vm_events(PGINODESTEAL, reap); spin_unlock(&inode_lock); dispose_list(&freeable); - up(&iprune_sem); - - if (current_is_kswapd()) - mod_page_state(kswapd_inodesteal, reap); - else - mod_page_state(pginodesteal, reap); + mutex_unlock(&iprune_mutex); } /* @@ -488,7 +453,7 @@ static void prune_icache(int nr_to_scan) * This function is passed the number of inodes to scan, and it returns the * total number of remaining possibly-reclaimable inodes. */ -static int shrink_icache_memory(int nr, unsigned int gfp_mask) +static int shrink_icache_memory(int nr, gfp_t gfp_mask) { if (nr) { /* @@ -522,7 +487,7 @@ repeat: continue; if (!test(inode, data)) continue; - if (inode->i_state & (I_FREEING|I_CLEAR)) { + if (inode->i_state & (I_FREEING|I_CLEAR|I_WILL_FREE)) { __wait_on_freeing_inode(inode); goto repeat; } @@ -547,7 +512,7 @@ repeat: continue; if (inode->i_sb != sb) continue; - if (inode->i_state & (I_FREEING|I_CLEAR)) { + if (inode->i_state & (I_FREEING|I_CLEAR|I_WILL_FREE)) { __wait_on_freeing_inode(inode); goto repeat; } @@ -697,7 +662,7 @@ static struct inode * get_new_inode_fast(struct super_block *sb, struct hlist_he return inode; } -static inline unsigned long hash(struct super_block *sb, unsigned long hashval) +static unsigned long hash(struct super_block *sb, unsigned long hashval) { unsigned long tmp; @@ -749,7 +714,7 @@ EXPORT_SYMBOL(iunique); struct inode *igrab(struct inode *inode) { spin_lock(&inode_lock); - if (!(inode->i_state & I_FREEING)) + if (!(inode->i_state & (I_FREEING|I_WILL_FREE))) __iget(inode); else /* @@ -770,6 +735,7 @@ EXPORT_SYMBOL(igrab); * @head: the head of the list to search * @test: callback used for comparisons between inodes * @data: opaque data pointer to pass to @test + * @wait: if true wait for the inode to be unlocked, if false do not * * ifind() searches for the inode specified by @data in the inode * cache. This is a generalized version of ifind_fast() for file systems where @@ -782,9 +748,9 @@ EXPORT_SYMBOL(igrab); * * Note, @test is called with the inode_lock held, so can't sleep. */ -static inline struct inode *ifind(struct super_block *sb, +static struct inode *ifind(struct super_block *sb, struct hlist_head *head, int (*test)(struct inode *, void *), - void *data) + void *data, const int wait) { struct inode *inode; @@ -793,7 +759,8 @@ static inline struct inode *ifind(struct super_block *sb, if (inode) { __iget(inode); spin_unlock(&inode_lock); - wait_on_inode(inode); + if (likely(wait)) + wait_on_inode(inode); return inode; } spin_unlock(&inode_lock); @@ -815,7 +782,7 @@ static inline struct inode *ifind(struct super_block *sb, * * Otherwise NULL is returned. */ -static inline struct inode *ifind_fast(struct super_block *sb, +static struct inode *ifind_fast(struct super_block *sb, struct hlist_head *head, unsigned long ino) { struct inode *inode; @@ -833,7 +800,7 @@ static inline struct inode *ifind_fast(struct super_block *sb, } /** - * ilookup5 - search for an inode in the inode cache + * ilookup5_nowait - search for an inode in the inode cache * @sb: super block of file system to search * @hashval: hash value (usually inode number) to search for * @test: callback used for comparisons between inodes @@ -845,7 +812,38 @@ static inline struct inode *ifind_fast(struct super_block *sb, * identification of an inode. * * If the inode is in the cache, the inode is returned with an incremented - * reference count. + * reference count. Note, the inode lock is not waited upon so you have to be + * very careful what you do with the returned inode. You probably should be + * using ilookup5() instead. + * + * Otherwise NULL is returned. + * + * Note, @test is called with the inode_lock held, so can't sleep. + */ +struct inode *ilookup5_nowait(struct super_block *sb, unsigned long hashval, + int (*test)(struct inode *, void *), void *data) +{ + struct hlist_head *head = inode_hashtable + hash(sb, hashval); + + return ifind(sb, head, test, data, 0); +} + +EXPORT_SYMBOL(ilookup5_nowait); + +/** + * ilookup5 - search for an inode in the inode cache + * @sb: super block of file system to search + * @hashval: hash value (usually inode number) to search for + * @test: callback used for comparisons between inodes + * @data: opaque data pointer to pass to @test + * + * ilookup5() uses ifind() to search for the inode specified by @hashval and + * @data in the inode cache. This is a generalized version of ilookup() for + * file systems where the inode number is not sufficient for unique + * identification of an inode. + * + * If the inode is in the cache, the inode lock is waited upon and the inode is + * returned with an incremented reference count. * * Otherwise NULL is returned. * @@ -856,7 +854,7 @@ struct inode *ilookup5(struct super_block *sb, unsigned long hashval, { struct hlist_head *head = inode_hashtable + hash(sb, hashval); - return ifind(sb, head, test, data); + return ifind(sb, head, test, data, 1); } EXPORT_SYMBOL(ilookup5); @@ -913,7 +911,7 @@ struct inode *iget5_locked(struct super_block *sb, unsigned long hashval, struct hlist_head *head = inode_hashtable + hash(sb, hashval); struct inode *inode; - inode = ifind(sb, head, test, data); + inode = ifind(sb, head, test, data, 1); if (inode) return inode; /* @@ -1010,29 +1008,30 @@ void generic_delete_inode(struct inode *inode) list_del_init(&inode->i_list); list_del_init(&inode->i_sb_list); - inode->i_state|=I_FREEING; + inode->i_state |= I_FREEING; inodes_stat.nr_inodes--; spin_unlock(&inode_lock); - if (inode->i_data.nrpages) - truncate_inode_pages(&inode->i_data, 0); - security_inode_delete(inode); if (op->delete_inode) { void (*delete)(struct inode *) = op->delete_inode; if (!is_bad_inode(inode)) DQUOT_INIT(inode); - /* s_op->delete_inode internally recalls clear_inode() */ + /* Filesystems implementing their own + * s_op->delete_inode are required to call + * truncate_inode_pages and clear_inode() + * internally */ delete(inode); - } else + } else { + truncate_inode_pages(&inode->i_data, 0); clear_inode(inode); + } spin_lock(&inode_lock); hlist_del_init(&inode->i_hash); spin_unlock(&inode_lock); wake_up_inode(inode); - if (inode->i_state != I_CLEAR) - BUG(); + BUG_ON(inode->i_state != I_CLEAR); destroy_inode(inode); } @@ -1046,22 +1045,27 @@ static void generic_forget_inode(struct inode *inode) if (!(inode->i_state & (I_DIRTY|I_LOCK))) list_move(&inode->i_list, &inode_unused); inodes_stat.nr_unused++; - spin_unlock(&inode_lock); - if (!sb || (sb->s_flags & MS_ACTIVE)) + if (!sb || (sb->s_flags & MS_ACTIVE)) { + spin_unlock(&inode_lock); return; + } + inode->i_state |= I_WILL_FREE; + spin_unlock(&inode_lock); write_inode_now(inode, 1); spin_lock(&inode_lock); + inode->i_state &= ~I_WILL_FREE; inodes_stat.nr_unused--; hlist_del_init(&inode->i_hash); } list_del_init(&inode->i_list); list_del_init(&inode->i_sb_list); - inode->i_state|=I_FREEING; + inode->i_state |= I_FREEING; inodes_stat.nr_inodes--; spin_unlock(&inode_lock); if (inode->i_data.nrpages) truncate_inode_pages(&inode->i_data, 0); clear_inode(inode); + wake_up_inode(inode); destroy_inode(inode); } @@ -1070,7 +1074,7 @@ static void generic_forget_inode(struct inode *inode) * inode when the usage count drops to zero, and * i_nlink is zero. */ -static void generic_drop_inode(struct inode *inode) +void generic_drop_inode(struct inode *inode) { if (!inode->i_nlink) generic_delete_inode(inode); @@ -1078,6 +1082,8 @@ static void generic_drop_inode(struct inode *inode) generic_forget_inode(inode); } +EXPORT_SYMBOL_GPL(generic_drop_inode); + /* * Called when we're dropping the last reference * to an inode. @@ -1104,15 +1110,16 @@ static inline void iput_final(struct inode *inode) * @inode: inode to put * * Puts an inode, dropping its usage count. If the inode use count hits - * zero the inode is also then freed and may be destroyed. + * zero, the inode is then freed and may also be destroyed. + * + * Consequently, iput() can sleep. */ void iput(struct inode *inode) { if (inode) { struct super_operations *op = inode->i_sb->s_op; - if (inode->i_state == I_CLEAR) - BUG(); + BUG_ON(inode->i_state == I_CLEAR); if (op && op->put_inode) op->put_inode(inode); @@ -1142,51 +1149,78 @@ sector_t bmap(struct inode * inode, sector_t block) res = inode->i_mapping->a_ops->bmap(inode->i_mapping, block); return res; } - EXPORT_SYMBOL(bmap); /** - * update_atime - update the access time - * @inode: inode accessed + * touch_atime - update the access time + * @mnt: mount the inode is accessed on + * @dentry: dentry accessed * * Update the accessed time on an inode and mark it for writeback. * This function automatically handles read only file systems and media, * as well as the "noatime" flag and inode specific "noatime" markers. */ -void update_atime(struct inode *inode) +void touch_atime(struct vfsmount *mnt, struct dentry *dentry) { + struct inode *inode = dentry->d_inode; struct timespec now; - if (IS_NOATIME(inode)) + if (IS_RDONLY(inode)) return; - if (IS_NODIRATIME(inode) && S_ISDIR(inode->i_mode)) + if (inode->i_flags & S_NOATIME) return; - if (IS_RDONLY(inode)) + if (inode->i_sb->s_flags & MS_NOATIME) + return; + if ((inode->i_sb->s_flags & MS_NODIRATIME) && S_ISDIR(inode->i_mode)) return; - now = current_fs_time(inode->i_sb); - if (!timespec_equal(&inode->i_atime, &now)) { - inode->i_atime = now; - mark_inode_dirty_sync(inode); - } else { - if (!timespec_equal(&inode->i_atime, &now)) - inode->i_atime = now; + /* + * We may have a NULL vfsmount when coming from NFSD + */ + if (mnt) { + if (mnt->mnt_flags & MNT_NOATIME) + return; + if ((mnt->mnt_flags & MNT_NODIRATIME) && S_ISDIR(inode->i_mode)) + return; + + if (mnt->mnt_flags & MNT_RELATIME) { + /* + * With relative atime, only update atime if the + * previous atime is earlier than either the ctime or + * mtime. + */ + if (timespec_compare(&inode->i_mtime, + &inode->i_atime) < 0 && + timespec_compare(&inode->i_ctime, + &inode->i_atime) < 0) + return; + } } -} -EXPORT_SYMBOL(update_atime); + now = current_fs_time(inode->i_sb); + if (timespec_equal(&inode->i_atime, &now)) + return; + + inode->i_atime = now; + mark_inode_dirty_sync(inode); +} +EXPORT_SYMBOL(touch_atime); /** - * inode_update_time - update mtime and ctime time - * @inode: inode accessed - * @ctime_too: update ctime too + * file_update_time - update mtime and ctime time + * @file: file accessed * - * Update the mtime time on an inode and mark it for writeback. - * When ctime_too is specified update the ctime too. + * Update the mtime and ctime members of an inode and mark the inode + * for writeback. Note that this function is meant exclusively for + * usage in the file write path of filesystems, and filesystems may + * choose to explicitly ignore update via this function with the + * S_NOCTIME inode flag, e.g. for network filesystem where these + * timestamps are handled by the server. */ -void inode_update_time(struct inode *inode, int ctime_too) +void file_update_time(struct file *file) { + struct inode *inode = file->f_path.dentry->d_inode; struct timespec now; int sync_it = 0; @@ -1196,20 +1230,21 @@ void inode_update_time(struct inode *inode, int ctime_too) return; now = current_fs_time(inode->i_sb); - if (!timespec_equal(&inode->i_mtime, &now)) + if (!timespec_equal(&inode->i_mtime, &now)) { + inode->i_mtime = now; sync_it = 1; - inode->i_mtime = now; + } - if (ctime_too) { - if (!timespec_equal(&inode->i_ctime, &now)) - sync_it = 1; + if (!timespec_equal(&inode->i_ctime, &now)) { inode->i_ctime = now; + sync_it = 1; } + if (sync_it) mark_inode_dirty_sync(inode); } -EXPORT_SYMBOL(inode_update_time); +EXPORT_SYMBOL(file_update_time); int inode_needs_sync(struct inode *inode) { @@ -1227,9 +1262,6 @@ EXPORT_SYMBOL(inode_needs_sync); */ #ifdef CONFIG_QUOTA -/* Function back in dquot.c */ -int remove_inode_dquot_ref(struct inode *, int, struct list_head *); - void remove_dquot_ref(struct super_block *sb, int type, struct list_head *tofree_head) { @@ -1259,29 +1291,21 @@ int inode_wait(void *word) } /* - * If we try to find an inode in the inode hash while it is being deleted, we - * have to wait until the filesystem completes its deletion before reporting - * that it isn't found. This is because iget will immediately call - * ->read_inode, and we want to be sure that evidence of the deletion is found - * by ->read_inode. + * If we try to find an inode in the inode hash while it is being + * deleted, we have to wait until the filesystem completes its + * deletion before reporting that it isn't found. This function waits + * until the deletion _might_ have completed. Callers are responsible + * to recheck inode state. + * + * It doesn't matter if I_LOCK is not set initially, a call to + * wake_up_inode() after removing from the hash list will DTRT. + * * This is called with inode_lock held. */ static void __wait_on_freeing_inode(struct inode *inode) { wait_queue_head_t *wq; DEFINE_WAIT_BIT(wait, &inode->i_state, __I_LOCK); - - /* - * I_FREEING and I_CLEAR are cleared in process context under - * inode_lock, so we have to give the tasks who would clear them - * a chance to run and acquire inode_lock. - */ - if (!(inode->i_state & I_LOCK)) { - spin_unlock(&inode_lock); - yield(); - spin_lock(&inode_lock); - return; - } wq = bit_waitqueue(&inode->i_state, __I_LOCK); prepare_to_wait(wq, &wait.wait, TASK_UNINTERRUPTIBLE); spin_unlock(&inode_lock); @@ -1299,6 +1323,42 @@ void wake_up_inode(struct inode *inode) wake_up_bit(&inode->i_state, __I_LOCK); } +/* + * We rarely want to lock two inodes that do not have a parent/child + * relationship (such as directory, child inode) simultaneously. The + * vast majority of file systems should be able to get along fine + * without this. Do not use these functions except as a last resort. + */ +void inode_double_lock(struct inode *inode1, struct inode *inode2) +{ + if (inode1 == NULL || inode2 == NULL || inode1 == inode2) { + if (inode1) + mutex_lock(&inode1->i_mutex); + else if (inode2) + mutex_lock(&inode2->i_mutex); + return; + } + + if (inode1 < inode2) { + mutex_lock_nested(&inode1->i_mutex, I_MUTEX_PARENT); + mutex_lock_nested(&inode2->i_mutex, I_MUTEX_CHILD); + } else { + mutex_lock_nested(&inode2->i_mutex, I_MUTEX_PARENT); + mutex_lock_nested(&inode1->i_mutex, I_MUTEX_CHILD); + } +} +EXPORT_SYMBOL(inode_double_lock); + +void inode_double_unlock(struct inode *inode1, struct inode *inode2) +{ + if (inode1) + mutex_unlock(&inode1->i_mutex); + + if (inode2 && inode2 != inode1) + mutex_unlock(&inode2->i_mutex); +} +EXPORT_SYMBOL(inode_double_unlock); + static __initdata unsigned long ihash_entries; static int __init set_ihash_entries(char *str) { @@ -1341,8 +1401,13 @@ void __init inode_init(unsigned long mempages) int loop; /* inode slab cache */ - inode_cachep = kmem_cache_create("inode_cache", sizeof(struct inode), - 0, SLAB_PANIC, init_once, NULL); + inode_cachep = kmem_cache_create("inode_cache", + sizeof(struct inode), + 0, + (SLAB_RECLAIM_ACCOUNT|SLAB_PANIC| + SLAB_MEM_SPREAD), + init_once, + NULL); set_shrinker(DEFAULT_SEEKS, shrink_icache_memory); /* Hash may have been set up in inode_init_early */