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/smbfs/inode.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'fs/smbfs') diff --git a/fs/smbfs/inode.c b/fs/smbfs/inode.c index 450c91941988..8fc5e50e142f 100644 --- a/fs/smbfs/inode.c +++ b/fs/smbfs/inode.c @@ -501,6 +501,8 @@ static int smb_fill_super(struct super_block *sb, void *raw_data, int silent) void *mem; static int warn_count; + lock_kernel(); + if (warn_count < 5) { warn_count++; printk(KERN_EMERG "smbfs is deprecated and will be removed" @@ -621,6 +623,7 @@ static int smb_fill_super(struct super_block *sb, void *raw_data, int silent) smb_new_dentry(sb->s_root); + unlock_kernel(); return 0; out_no_root: @@ -643,9 +646,11 @@ out_wrong_data: out_no_data: printk(KERN_ERR "smb_fill_super: missing data argument\n"); out_fail: + unlock_kernel(); return -EINVAL; out_no_server: printk(KERN_ERR "smb_fill_super: cannot allocate struct smb_sb_info\n"); + unlock_kernel(); return -ENOMEM; } -- cgit v1.2.3