From 4504230a71566785a05d3e6b53fa1ee071b864eb Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 3 Aug 2009 23:28:35 +0200 Subject: freeze_bdev: grab active reference to frozen superblocks Currently we held s_umount while a filesystem is frozen, despite that we might return to userspace and unlock it from a different process. Instead grab an active reference to keep the file system busy and add an explicit check for frozen filesystems in remount and reject the remount instead of blocking on s_umount. Add a new get_active_super helper to super.c for use by freeze_bdev that grabs an active reference to a superblock from a given block device. Signed-off-by: Christoph Hellwig Signed-off-by: Al Viro --- include/linux/fs.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include') diff --git a/include/linux/fs.h b/include/linux/fs.h index 72dfbd42397..502d96ef345 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2334,6 +2334,7 @@ extern void get_filesystem(struct file_system_type *fs); extern void put_filesystem(struct file_system_type *fs); extern struct file_system_type *get_fs_type(const char *name); extern struct super_block *get_super(struct block_device *); +extern struct super_block *get_active_super(struct block_device *bdev); extern struct super_block *user_get_super(dev_t); extern void drop_super(struct super_block *sb); -- cgit v1.2.3-70-g09d2