From: Miklos Szeredi Keep track of vfsmounts belonging to a superblock. List is protected by vfsmount_lock. Signed-off-by: Miklos Szeredi --- fs/namespace.c | 10 ++++++++-- fs/super.c | 7 +++++++ include/linux/fs.h | 1 + include/linux/mount.h | 1 + 4 files changed, 17 insertions(+), 2 deletions(-) Index: linux-2.6/include/linux/fs.h =================================================================== --- linux-2.6.orig/include/linux/fs.h 2011-01-12 15:47:09.000000000 +0100 +++ linux-2.6/include/linux/fs.h 2011-01-12 15:47:12.000000000 +0100 @@ -1384,6 +1384,7 @@ struct super_block { #else struct list_head s_files; #endif + struct list_head s_mounts; /* list of mounts */ /* s_dentry_lru, s_nr_dentry_unused protected by dcache.c lru locks */ struct list_head s_dentry_lru; /* unused dentry lru */ int s_nr_dentry_unused; /* # of dentry on lru */ Index: linux-2.6/include/linux/mount.h =================================================================== --- linux-2.6.orig/include/linux/mount.h 2011-01-12 15:47:09.000000000 +0100 +++ linux-2.6/include/linux/mount.h 2011-01-12 15:47:12.000000000 +0100 @@ -67,6 +67,7 @@ struct vfsmount { #endif struct list_head mnt_mounts; /* list of children, anchored here */ struct list_head mnt_child; /* and going through their mnt_child */ + struct list_head mnt_instance; /* mount instance on sb->s_mounts */ int mnt_flags; /* 4 bytes hole on 64bits arches without fsnotify */ #ifdef CONFIG_FSNOTIFY Index: linux-2.6/fs/namespace.c =================================================================== --- linux-2.6.orig/fs/namespace.c 2011-01-12 15:47:09.000000000 +0100 +++ linux-2.6/fs/namespace.c 2011-01-12 15:47:12.000000000 +0100 @@ -705,6 +705,10 @@ static struct vfsmount *clone_mnt(struct if (!list_empty(&old->mnt_expire)) list_add(&mnt->mnt_expire, &old->mnt_expire); } + + br_write_lock(vfsmount_lock); + list_add_tail(&mnt->mnt_instance, &mnt->mnt_sb->s_mounts); + br_write_unlock(vfsmount_lock); } return mnt; @@ -714,9 +718,13 @@ static struct vfsmount *clone_mnt(struct } static inline void mntfree(struct vfsmount *mnt) +__releases(vfsmount_lock) { struct super_block *sb = mnt->mnt_sb; + list_del(&mnt->mnt_instance); + br_write_unlock(vfsmount_lock); + /* * This probably indicates that somebody messed * up a mnt_want/drop_write() pair. If this @@ -768,7 +776,6 @@ static inline void __mntput(struct vfsmo acct_auto_close_mnt(mnt); goto put_again; } - br_write_unlock(vfsmount_lock); mntfree(mnt); } #else @@ -786,7 +793,6 @@ static inline void __mntput(struct vfsmo acct_auto_close_mnt(mnt); goto put_again; } - br_write_unlock(vfsmount_lock); mntfree(mnt); } #endif Index: linux-2.6/fs/super.c =================================================================== --- linux-2.6.orig/fs/super.c 2011-01-12 15:47:10.000000000 +0100 +++ linux-2.6/fs/super.c 2011-01-12 15:47:12.000000000 +0100 @@ -75,6 +75,7 @@ static struct super_block *alloc_super(s INIT_HLIST_BL_HEAD(&s->s_anon); INIT_LIST_HEAD(&s->s_inodes); INIT_LIST_HEAD(&s->s_dentry_lru); + INIT_LIST_HEAD(&s->s_mounts); init_rwsem(&s->s_umount); mutex_init(&s->s_lock); lockdep_set_class(&s->s_umount, &type->s_umount_key); @@ -128,6 +129,7 @@ static inline void destroy_super(struct free_percpu(s->s_files); #endif security_sb_free(s); + WARN_ON(!list_empty(&s->s_mounts)); kfree(s->s_subtype); kfree(s->s_options); kfree(s); @@ -1018,6 +1020,11 @@ vfs_kern_mount(struct file_system_type * mnt->mnt_parent = mnt; up_write(&mnt->mnt_sb->s_umount); free_secdata(secdata); + + br_write_lock(vfsmount_lock); + list_add_tail(&mnt->mnt_instance, &mnt->mnt_sb->s_mounts); + br_write_unlock(vfsmount_lock); + return mnt; out_sb: dput(mnt->mnt_root); -- -- 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/