Let locking subsystem decide on mutex management.
As reported by Andrew Morton this patch fixes a bug:
"
lock_ufs() is assuming that on non-preempt uniprocessor, the calling
code will run atomically up to the matching unlock_ufs().
But that isn't true. The very first site I looked at (ufs_frag_map)
does sb_bread() under lock_ufs(). And sb_bread() will call schedule(),
very commonly.
The ->mutex_owner stuff is a bit hacky but should work OK.
"
Cc: Evgeniy Dushistov <[email protected]>
Cc: Andrew Morton <[email protected]>
Signed-off-by: Fabian Frederick <[email protected]>
---
fs/ufs/super.c | 4 ----
1 file changed, 4 deletions(-)
diff --git a/fs/ufs/super.c b/fs/ufs/super.c
index e515e99..8092d37 100644
--- a/fs/ufs/super.c
+++ b/fs/ufs/super.c
@@ -95,22 +95,18 @@
void lock_ufs(struct super_block *sb)
{
-#if defined(CONFIG_SMP) || defined (CONFIG_PREEMPT)
struct ufs_sb_info *sbi = UFS_SB(sb);
mutex_lock(&sbi->mutex);
sbi->mutex_owner = current;
-#endif
}
void unlock_ufs(struct super_block *sb)
{
-#if defined(CONFIG_SMP) || defined (CONFIG_PREEMPT)
struct ufs_sb_info *sbi = UFS_SB(sb);
sbi->mutex_owner = NULL;
mutex_unlock(&sbi->mutex);
-#endif
}
static struct inode *ufs_nfs_get_inode(struct super_block *sb, u64 ino, u32 generation)
--
2.1.0