locks: don't call ->copy_lock methods on return of conflicting locks

The file_lock structure is used both as a heavy-weight representation of
an active lock, with pointers to reference-counted structures, etc., and
as a simple container for parameters that describe a file lock.

The conflicting lock returned from __posix_lock_file is an example of
the latter; so don't call the filesystem or lock manager callbacks when
copying to it.  This also saves the need for an unnecessary
locks_init_lock in the nfsv4 server.

Thanks to Trond for pointing out the error.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>

4 files changed, 4 insertions, 6 deletions

diff --git a/fs/lockd/svclock.c b/fs/lockd/svclock.c
index 1f122c1940af..4d81553d2948 100644
--- a/fs/lockd/svclock.c
+++ b/fs/lockd/svclock.c
@@ -632,7 +632,7 @@ nlmsvc_update_deferred_block(struct nlm_block *block, struct file_lock *conf,
                 block->b_flags |= B_TIMED_OUT;
         if (conf) {
                 if (block->b_fl)
-                        locks_copy_lock(block->b_fl, conf);
+                        __locks_copy_lock(block->b_fl, conf);
         }
 }
 
diff --git a/fs/locks.c b/fs/locks.c
index 2e0fa661e423..e1ea2fe03681 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -224,7 +224,7 @@ static void locks_copy_private(struct file_lock *new, struct file_lock *fl)
 /*
  * Initialize a new lock from an existing file_lock structure.
  */
-static void __locks_copy_lock(struct file_lock *new, const struct file_lock *fl)
+void __locks_copy_lock(struct file_lock *new, const struct file_lock *fl)
 {
         new->fl_owner = fl->fl_owner;
         new->fl_pid = fl->fl_pid;
@@ -833,7 +833,7 @@ static int __posix_lock_file(struct inode *inode, struct file_lock *request, str
                         if (!posix_locks_conflict(request, fl))
                                 continue;
                         if (conflock)
-                                locks_copy_lock(conflock, fl);
+                                __locks_copy_lock(conflock, fl);
                         error = -EAGAIN;
                         if (!(request->fl_flags & FL_SLEEP))
                                 goto out;
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 55dfdd71f1b0..8799b8708188 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -2712,9 +2712,6 @@ nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
         * Note: locks.c uses the BKL to protect the inode's lock list.
         */
 
-        /* XXX?: Just to divert the locks_release_private at the start of
-         * locks_copy_lock: */
-        locks_init_lock(&conflock);
         err = vfs_lock_file(filp, cmd, &file_lock, &conflock);
         switch (-err) {
         case 0: /* success! */
diff --git a/include/linux/fs.h b/include/linux/fs.h
index cc2be2cf7d41..6556f2f967e5 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -973,6 +973,7 @@ extern int do_sync_mapping_range(struct address_space *mapping, loff_t offset,
 /* fs/locks.c */
 extern void locks_init_lock(struct file_lock *);
 extern void locks_copy_lock(struct file_lock *, struct file_lock *);
+extern void __locks_copy_lock(struct file_lock *, const struct file_lock *);
 extern void locks_remove_posix(struct file *, fl_owner_t);
 extern void locks_remove_flock(struct file *);
 extern void posix_test_lock(struct file *, struct file_lock *);