locks: allow ->lock() to return FILE_LOCK_DEFERRED

Allow filesystem's ->lock() method to call posix_lock_file() instead of
posix_lock_file_wait(), and return FILE_LOCK_DEFERRED.  This makes it
possible to implement a such a ->lock() function, that works with the lock
manager, which needs the call to be asynchronous.

Now the vfs_lock_file() helper can be used, so this is a cleanup as well.

Signed-off-by: Miklos Szeredi <[email protected]>
Cc: "J. Bruce Fields" <[email protected]>
Cc: Trond Myklebust <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: David Teigland <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

0 files changed, 0 insertions, 0 deletions