lockdep: per filesystem inode lock class

Give each filesystem its own inode lock class. The various filesystems have
different locking order wrt the inode locks; esp. the pseudo filesystems differ
from the rest.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>

diff --git a/fs/inode.c b/fs/inode.c
index 29f5068..bf6adf1 100644 (file)
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -142,6 +142,15 @@ static struct inode *alloc_inode(struct super_block *sb)
                        return NULL;
                }
 
+               spin_lock_init(&inode->i_lock);
+               lockdep_set_class(&inode->i_lock, &sb->s_type->i_lock_key);
+
+               mutex_init(&inode->i_mutex);
+               lockdep_set_class(&inode->i_mutex, &sb->s_type->i_mutex_key);
+
+               init_rwsem(&inode->i_alloc_sem);
+               lockdep_set_class(&inode->i_alloc_sem, &sb->s_type->i_alloc_sem_key);
+
                mapping->a_ops = &empty_aops;
                mapping->host = inode;
                mapping->flags = 0;
@@ -190,8 +199,6 @@ 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);
-       mutex_init(&inode->i_mutex);
-       init_rwsem(&inode->i_alloc_sem);
        INIT_RADIX_TREE(&inode->i_data.page_tree, GFP_ATOMIC);
        rwlock_init(&inode->i_data.tree_lock);
        spin_lock_init(&inode->i_data.i_mmap_lock);
@@ -199,7 +206,6 @@ void inode_init_once(struct inode *inode)
        spin_lock_init(&inode->i_data.private_lock);
        INIT_RAW_PRIO_TREE_ROOT(&inode->i_data.i_mmap);
        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);

diff --git a/include/linux/fs.h b/include/linux/fs.h
index 16421f6..0cad20e 100644 (file)
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1302,8 +1302,13 @@ struct file_system_type {
        struct module *owner;
        struct file_system_type * next;
        struct list_head fs_supers;
+
        struct lock_class_key s_lock_key;
        struct lock_class_key s_umount_key;
+
+       struct lock_class_key i_lock_key;
+       struct lock_class_key i_mutex_key;
+       struct lock_class_key i_alloc_sem_key;
 };
 
 extern int get_sb_bdev(struct file_system_type *fs_type,