From cf51624999e56c88154b5f7d451a265db6aabff7 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Mon, 3 Jul 2006 00:25:27 -0700 Subject: [PATCH] [PATCH] lockdep: annotate ->s_lock Teach special (per-filesystem) locking code to the lock validator. Minimal effect on non-lockdep kernels: one extra parameter to alloc_super(). Signed-off-by: Ingo Molnar Signed-off-by: Arjan van de Ven Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/super.c | 10 ++++++++-- include/linux/fs.h | 1 + 2 files changed, 9 insertions(+), 2 deletions(-) diff --git a/fs/super.c b/fs/super.c index 9b780c42d845..5a4fe8be462a 100644 --- a/fs/super.c +++ b/fs/super.c @@ -53,7 +53,7 @@ DEFINE_SPINLOCK(sb_lock); * Allocates and initializes a new &struct super_block. alloc_super() * returns a pointer new superblock or %NULL if allocation had failed. */ -static struct super_block *alloc_super(void) +static struct super_block *alloc_super(struct file_system_type *type) { struct super_block *s = kzalloc(sizeof(struct super_block), GFP_USER); static struct super_operations default_op; @@ -72,6 +72,12 @@ static struct super_block *alloc_super(void) INIT_LIST_HEAD(&s->s_inodes); init_rwsem(&s->s_umount); mutex_init(&s->s_lock); + /* + * The locking rules for s_lock are up to the + * filesystem. For example ext3fs has different + * lock ordering than usbfs: + */ + lockdep_set_class(&s->s_lock, &type->s_lock_key); down_write(&s->s_umount); s->s_count = S_BIAS; atomic_set(&s->s_active, 1); @@ -295,7 +301,7 @@ struct super_block *sget(struct file_system_type *type, } if (!s) { spin_unlock(&sb_lock); - s = alloc_super(); + s = alloc_super(type); if (!s) return ERR_PTR(-ENOMEM); goto retry; diff --git a/include/linux/fs.h b/include/linux/fs.h index 05ded9e76b23..0a3ea52d711e 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1295,6 +1295,7 @@ struct file_system_type { struct module *owner; struct file_system_type * next; struct list_head fs_supers; + struct lock_class_key s_lock_key; }; extern int get_sb_bdev(struct file_system_type *fs_type,