locks: Copy fl_lmops information for conflock in locks_copy_conflock()

Commit d5b9026a67 ([PATCH] knfsd: locks: flag NFSv4-owned locks) using
fl_lmops field in file_lock for checking nfsd4 lockowner.

But, commit 1a747ee0cc (locks: don't call ->copy_lock methods on return
of conflicting locks) causes the fl_lmops of conflock always be NULL.

Also, commit 0996905f93 (lockd: posix_test_lock() should not call
locks_copy_lock()) caused the fl_lmops of conflock always be NULL too.

Make sure copy the private information by fl_copy_lock() in struct
file_lock_operations, merge __locks_copy_lock() to fl_copy_lock().

Jeff advice, "Set fl_lmops on conflocks, but don't set fl_ops.
fl_ops are superfluous, since they are callbacks into the filesystem.
There should be no need to bother the filesystem at all with info
in a conflock. But, lock _ownership_ matters for conflocks and that's
indicated by the fl_lmops. So you really do want to copy the fl_lmops
for conflocks I think."

v5: add missing calling of locks_release_private() in nlmsvc_testlock()
v4: only copy fl_lmops for conflock, don't copy fl_ops

Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: Jeff Layton <jlayton@primarydata.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/fs/lockd/svclock.c b/fs/lockd/svclock.c
index 2a6170133c1d..acfa94d5b489 100644
--- a/fs/lockd/svclock.c
+++ b/fs/lockd/svclock.c
@@ -586,6 +586,7 @@ conf_lock:
         conflock->fl.fl_type = lock->fl.fl_type;
         conflock->fl.fl_start = lock->fl.fl_start;
         conflock->fl.fl_end = lock->fl.fl_end;
+        locks_release_private(&lock->fl);
         ret = nlm_lck_denied;
 out:
         if (block)