From db71922217a214e5c9268448e537b54fc1f301ea Mon Sep 17 00:00:00 2001 From: Jan Blunck Date: Sun, 15 Aug 2010 22:51:10 +0200 Subject: 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 Signed-off-by: Arnd Bergmann Cc: Matthew Wilcox Cc: Christoph Hellwig --- fs/ocfs2/super.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'fs/ocfs2/super.c') diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c index fa1be1b304d..b7e4f2d19d4 100644 --- a/fs/ocfs2/super.c +++ b/fs/ocfs2/super.c @@ -1002,6 +1002,8 @@ static int ocfs2_fill_super(struct super_block *sb, void *data, int silent) char nodestr[8]; struct ocfs2_blockcheck_stats stats; + lock_kernel(); + mlog_entry("%p, %p, %i", sb, data, silent); if (!ocfs2_parse_options(sb, data, &parsed_options, 0)) { @@ -1179,6 +1181,7 @@ static int ocfs2_fill_super(struct super_block *sb, void *data, int silent) atomic_set(&osb->vol_state, VOLUME_DISABLED); wake_up(&osb->osb_mount_event); mlog_exit(status); + unlock_kernel(); return status; } } @@ -1193,6 +1196,7 @@ static int ocfs2_fill_super(struct super_block *sb, void *data, int silent) ocfs2_orphan_scan_start(osb); mlog_exit(status); + unlock_kernel(); return status; read_super_error: @@ -1208,6 +1212,7 @@ read_super_error: } mlog_exit(status); + unlock_kernel(); return status; } -- cgit v1.2.3