ext2: Add ext2_sb_info s_lock spinlock

Add a spinlock that protects against concurrent modifications of
s_mount_state, s_blocks_last, s_overhead_last and the content of the
superblock's buffer pointed to by sbi->s_es. The spinlock is now used in
ext2_xattr_update_super_block() which was setting the
EXT2_FEATURE_COMPAT_EXT_ATTR flag on the superblock without protection
before. Likewise the spinlock is used in ext2_show_options() to have a
consistent view of the mount options.

This is a preparation patch for removing the BKL from ext2 in the next
patch.

Signed-off-by: Jan Blunck <jblunck@suse.de>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Jan Kara <jack@suse.cz>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Jan Kara <jack@suse.cz>
This commit is contained in:
Jan Blunck
2010-04-14 14:38:38 +02:00
committed by Jan Kara
parent 4c96a68bfc
commit c15271f4e7
4 changed files with 39 additions and 1 deletions

View File

@@ -106,6 +106,15 @@ struct ext2_sb_info {
spinlock_t s_rsv_window_lock;
struct rb_root s_rsv_window_root;
struct ext2_reserve_window_node s_rsv_window_head;
/*
* s_lock protects against concurrent modifications of s_mount_state,
* s_blocks_last, s_overhead_last and the content of superblock's
* buffer pointed to by sbi->s_es.
*
* Note: It is used in ext2_show_options() to provide a consistent view
* of the mount options.
*/
spinlock_t s_lock;
};
static inline spinlock_t *