path: root/fs/ext2/super.c
diff options
authorJan Blunck <jblunck@infradead.org>2010-08-15 22:51:10 +0200
committerArnd Bergmann <arnd@arndb.de>2010-10-04 21:10:10 +0200
commitdb71922217a214e5c9268448e537b54fc1f301ea (patch)
tree9c9afbf29411547891f6968e5ade29ce59d66c07 /fs/ext2/super.c
parent899611ee7d373e5eeda08e9a8632684e1ebbbf00 (diff)
BKL: Explicitly add BKL around get_sb/fill_super
This patch is a preparation necessary to remove the BKL from do_new_mount(). It explicitly adds calls to lock_kernel()/unlock_kernel() around get_sb/fill_super operations for filesystems that still uses the BKL. I've read through all the code formerly covered by the BKL inside do_kern_mount() and have satisfied myself that it doesn't need the BKL any more. do_kern_mount() is already called without the BKL when mounting the rootfs and in nfsctl. do_kern_mount() calls vfs_kern_mount(), which is called from various places without BKL: simple_pin_fs(), nfs_do_clone_mount() through nfs_follow_mountpoint(), afs_mntpt_do_automount() through afs_mntpt_follow_link(). Both later functions are actually the filesystems follow_link inode operation. vfs_kern_mount() is calling the specified get_sb function and lets the filesystem do its job by calling the given fill_super function. Therefore I think it is safe to push down the BKL from the VFS to the low-level filesystems get_sb/fill_super operation. [arnd: do not add the BKL to those file systems that already don't use it elsewhere] Signed-off-by: Jan Blunck <jblunck@infradead.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Matthew Wilcox <matthew@wil.cx> Cc: Christoph Hellwig <hch@infradead.org>
Diffstat (limited to 'fs/ext2/super.c')
1 files changed, 8 insertions, 2 deletions
diff --git a/fs/ext2/super.c b/fs/ext2/super.c
index 1ec602673ea..f98c390caf1 100644
--- a/fs/ext2/super.c
+++ b/fs/ext2/super.c
@@ -747,15 +747,18 @@ static int ext2_fill_super(struct super_block *sb, void *data, int silent)
__le32 features;
int err;
+ lock_kernel();
+ err = -ENOMEM;
sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
if (!sbi)
- return -ENOMEM;
+ goto failed_unlock;
sbi->s_blockgroup_lock =
kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
if (!sbi->s_blockgroup_lock) {
- return -ENOMEM;
+ goto failed_unlock;
sb->s_fs_info = sbi;
sbi->s_sb_block = sb_block;
@@ -1083,6 +1086,7 @@ static int ext2_fill_super(struct super_block *sb, void *data, int silent)
if (ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY))
sb->s_flags |= MS_RDONLY;
+ unlock_kernel();
return 0;
@@ -1107,6 +1111,8 @@ failed_sbi:
sb->s_fs_info = NULL;
+ unlock_kernel();
return ret;