This implements the ability to remove inodes in a particular slab from inode cache. In order to remove an inode we may have to write out the pages of an inode, the inode itself and remove the dentries referring to the node. Provide generic functionality that can be used by filesystems that have their own inode caches to also tie into the defragmentation functions that are made available here. Reviewed-by: Rik van Riel Signed-off-by: Christoph Lameter --- fs/inode.c | 96 +++++++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/fs.h | 6 +++ 2 files changed, 102 insertions(+) Index: linux-2.6/fs/inode.c =================================================================== --- linux-2.6.orig/fs/inode.c 2007-10-17 13:35:52.000000000 -0700 +++ linux-2.6/fs/inode.c 2007-11-06 12:56:15.000000000 -0800 @@ -1369,6 +1369,101 @@ static int __init set_ihash_entries(char } __setup("ihash_entries=", set_ihash_entries); +void *get_inodes(struct kmem_cache *s, int nr, void **v) +{ + int i; + + spin_lock(&inode_lock); + for (i = 0; i < nr; i++) { + struct inode *inode = v[i]; + + if (inode->i_state & (I_FREEING|I_CLEAR|I_WILL_FREE)) + v[i] = NULL; + else + __iget(inode); + } + spin_unlock(&inode_lock); + return NULL; +} +EXPORT_SYMBOL(get_inodes); + +/* + * Function for filesystems that embedd struct inode into their own + * structures. The offset is the offset of the struct inode in the fs inode. + */ +void *fs_get_inodes(struct kmem_cache *s, int nr, void **v, + unsigned long offset) +{ + int i; + + for (i = 0; i < nr; i++) + v[i] += offset; + + return get_inodes(s, nr, v); +} +EXPORT_SYMBOL(fs_get_inodes); + +void kick_inodes(struct kmem_cache *s, int nr, void **v, void *private) +{ + struct inode *inode; + int i; + int abort = 0; + LIST_HEAD(freeable); + struct super_block *sb; + + for (i = 0; i < nr; i++) { + inode = v[i]; + if (!inode) + continue; + + if (inode_has_buffers(inode) || inode->i_data.nrpages) { + if (remove_inode_buffers(inode)) + invalidate_mapping_pages(&inode->i_data, + 0, -1); + } + + /* Invalidate children and dentry */ + if (S_ISDIR(inode->i_mode)) { + struct dentry *d = d_find_alias(inode); + + if (d) { + d_invalidate(d); + dput(d); + } + } + + if (inode->i_state & I_DIRTY) + write_inode_now(inode, 1); + + d_prune_aliases(inode); + } + + mutex_lock(&iprune_mutex); + for (i = 0; i < nr; i++) { + inode = v[i]; + if (!inode) + continue; + + sb = inode->i_sb; + iput(inode); + if (abort || !(sb->s_flags & MS_ACTIVE)) + continue; + + spin_lock(&inode_lock); + abort = !can_unuse(inode); + + if (!abort) { + list_move(&inode->i_list, &freeable); + inode->i_state |= I_FREEING; + inodes_stat.nr_unused--; + } + spin_unlock(&inode_lock); + } + dispose_list(&freeable); + mutex_unlock(&iprune_mutex); +} +EXPORT_SYMBOL(kick_inodes); + /* * Initialize the waitqueues and inode hash table. */ @@ -1408,6 +1503,7 @@ void __init inode_init(void) SLAB_MEM_SPREAD), init_once); register_shrinker(&icache_shrinker); + kmem_cache_setup_defrag(inode_cachep, get_inodes, kick_inodes); /* Hash may have been set up in inode_init_early */ if (!hashdist) Index: linux-2.6/include/linux/fs.h =================================================================== --- linux-2.6.orig/include/linux/fs.h 2007-10-25 18:28:41.000000000 -0700 +++ linux-2.6/include/linux/fs.h 2007-11-06 12:56:15.000000000 -0800 @@ -1776,6 +1776,12 @@ static inline void insert_inode_hash(str __insert_inode_hash(inode, inode->i_ino); } +/* Helper functions for inode defragmentation support in filesystems */ +extern void kick_inodes(struct kmem_cache *, int, void **, void *); +extern void *get_inodes(struct kmem_cache *, int nr, void **); +extern void *fs_get_inodes(struct kmem_cache *, int nr, void **, + unsigned long offset); + extern struct file * get_empty_filp(void); extern void file_move(struct file *f, struct list_head *list); extern void file_kill(struct file *f); -- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/