lockd: add code to handle deferred lock requests
Rewrite nlmsvc_lock() to use the asynchronous interface.
As with testlock, we answer nlm requests in nlmsvc_lock by first looking up
the block and then using the results we find in the block if B_QUEUED is
set, and calling vfs_lock_file() otherwise.
If this a new lock request and we get -EINPROGRESS return on a non-blocking
request then we defer the request.
Also modify nlmsvc_unlock() to call the filesystem method if appropriate.
Signed-off-by: Marc Eshel <eshel@almaden.ibm.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
diff --git a/fs/lockd/svcproc.c b/fs/lockd/svcproc.c
index 40b5cf4..9cd5c8b 100644
--- a/fs/lockd/svcproc.c
+++ b/fs/lockd/svcproc.c
@@ -175,6 +175,8 @@
/* Now try to lock the file */
resp->status = cast_status(nlmsvc_lock(rqstp, file, &argp->lock,
argp->block, &argp->cookie));
+ if (resp->status == nlm_drop_reply)
+ return rpc_drop_reply;
dprintk("lockd: LOCK status %d\n", ntohl(resp->status));
nlm_release_host(host);