From 13cf199d0088b77ab08a9594df2e73e775317ed2 Mon Sep 17 00:00:00 2001 From: Amir Goldstein Date: Mon, 12 Jun 2017 09:54:40 +0300 Subject: ovl: allocate an ovl_inode struct We need some more space to store overlay inode data in memory, so allocate overlay inodes from a slab of struct ovl_inode. Signed-off-by: Amir Goldstein Signed-off-by: Miklos Szeredi --- fs/overlayfs/super.c | 56 ++++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 54 insertions(+), 2 deletions(-) (limited to 'fs/overlayfs/super.c') diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c index 4882ffb37bae..ed916018fe1a 100644 --- a/fs/overlayfs/super.c +++ b/fs/overlayfs/super.c @@ -165,6 +165,27 @@ static const struct dentry_operations ovl_reval_dentry_operations = { .d_weak_revalidate = ovl_dentry_weak_revalidate, }; +static struct kmem_cache *ovl_inode_cachep; + +static struct inode *ovl_alloc_inode(struct super_block *sb) +{ + struct ovl_inode *oi = kmem_cache_alloc(ovl_inode_cachep, GFP_KERNEL); + + return &oi->vfs_inode; +} + +static void ovl_i_callback(struct rcu_head *head) +{ + struct inode *inode = container_of(head, struct inode, i_rcu); + + kmem_cache_free(ovl_inode_cachep, OVL_I(inode)); +} + +static void ovl_destroy_inode(struct inode *inode) +{ + call_rcu(&inode->i_rcu, ovl_i_callback); +} + static void ovl_put_super(struct super_block *sb) { struct ovl_fs *ufs = sb->s_fs_info; @@ -263,12 +284,14 @@ static int ovl_remount(struct super_block *sb, int *flags, char *data) } static const struct super_operations ovl_super_operations = { + .alloc_inode = ovl_alloc_inode, + .destroy_inode = ovl_destroy_inode, + .drop_inode = generic_delete_inode, .put_super = ovl_put_super, .sync_fs = ovl_sync_fs, .statfs = ovl_statfs, .show_options = ovl_show_options, .remount_fs = ovl_remount, - .drop_inode = generic_delete_inode, }; enum { @@ -1038,14 +1061,43 @@ static struct file_system_type ovl_fs_type = { }; MODULE_ALIAS_FS("overlay"); +static void ovl_inode_init_once(void *foo) +{ + struct ovl_inode *oi = foo; + + inode_init_once(&oi->vfs_inode); +} + static int __init ovl_init(void) { - return register_filesystem(&ovl_fs_type); + int err; + + ovl_inode_cachep = kmem_cache_create("ovl_inode", + sizeof(struct ovl_inode), 0, + (SLAB_RECLAIM_ACCOUNT| + SLAB_MEM_SPREAD|SLAB_ACCOUNT), + ovl_inode_init_once); + if (ovl_inode_cachep == NULL) + return -ENOMEM; + + err = register_filesystem(&ovl_fs_type); + if (err) + kmem_cache_destroy(ovl_inode_cachep); + + return err; } static void __exit ovl_exit(void) { unregister_filesystem(&ovl_fs_type); + + /* + * Make sure all delayed rcu free inodes are flushed before we + * destroy cache. + */ + rcu_barrier(); + kmem_cache_destroy(ovl_inode_cachep); + } module_init(ovl_init); -- cgit v1.2.3-59-g8ed1b