path: root/fs/freevxfs/vxfs_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/freevxfs/vxfs_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/freevxfs/vxfs_super.c')
1 files changed, 6 insertions, 1 deletions
diff --git a/fs/freevxfs/vxfs_super.c b/fs/freevxfs/vxfs_super.c
index dc0c041e85c..eb2b9e09c99 100644
--- a/fs/freevxfs/vxfs_super.c
+++ b/fs/freevxfs/vxfs_super.c
@@ -148,7 +148,7 @@ static int vxfs_remount(struct super_block *sb, int *flags, char *data)
* The superblock on success, else %NULL.
* Locking:
- * We are under the bkl and @sbp->s_lock.
+ * We are under @sbp->s_lock.
static int vxfs_fill_super(struct super_block *sbp, void *dp, int silent)
@@ -159,11 +159,14 @@ static int vxfs_fill_super(struct super_block *sbp, void *dp, int silent)
struct inode *root;
int ret = -EINVAL;
+ lock_kernel();
sbp->s_flags |= MS_RDONLY;
infp = kzalloc(sizeof(*infp), GFP_KERNEL);
if (!infp) {
printk(KERN_WARNING "vxfs: unable to allocate incore superblock\n");
+ unlock_kernel();
return -ENOMEM;
@@ -236,6 +239,7 @@ static int vxfs_fill_super(struct super_block *sbp, void *dp, int silent)
goto out_free_ilist;
+ unlock_kernel();
return 0;
@@ -245,6 +249,7 @@ out_free_ilist:
+ unlock_kernel();
return ret;