push BKL down into ->put_super

Move BKL into ->put_super from the only caller.  A couple of
filesystems had trivial enough ->put_super (only kfree and NULLing of
s_fs_info + stuff in there) to not get any locking: coda, cramfs, efs,
hugetlbfs, omfs, qnx4, shmem, all others got the full treatment.  Most
of them probably don't need it, but I'd rather sort that out individually.
Preferably after all the other BKL pushdowns in that area.

[AV: original used to move lock_super() down as well; these changes are
removed since we don't do lock_super() at all in generic_shutdown_super()
now]
[AV: fuse, btrfs and xfs are known to need no damn BKL, exempt]

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 5 insertions, 0 deletions

diff --git a/fs/ecryptfs/super.c b/fs/ecryptfs/super.c
index fa4c7e7d15d9..12d649602d3a 100644
--- a/fs/ecryptfs/super.c
+++ b/fs/ecryptfs/super.c
@@ -27,6 +27,7 @@
 #include <linux/mount.h>
 #include <linux/key.h>
 #include <linux/seq_file.h>
+#include <linux/smp_lock.h>
 #include <linux/file.h>
 #include <linux/crypto.h>
 #include "ecryptfs_kernel.h"
@@ -120,9 +121,13 @@ static void ecryptfs_put_super(struct super_block *sb)
 {
         struct ecryptfs_sb_info *sb_info = ecryptfs_superblock_to_private(sb);
 
+        lock_kernel();
+
         ecryptfs_destroy_mount_crypt_stat(&sb_info->mount_crypt_stat);
         kmem_cache_free(ecryptfs_sb_info_cache, sb_info);
         ecryptfs_set_superblock_private(sb, NULL);
+
+        unlock_kernel();
 }
 
 /**