lockd: Remove unneeded initialization of file_lock::c.flc_flags

Since commit 75c7940 ("lockd: set missing fl_flags field when
retrieving args"), nlmsvc_retrieve_args() initializes the flc_flags
field. svcxdr_decode_lock() no longer needs to do this.

This clean up removes one dependency on the nlm_lock:fl field. No
behavior change is expected.

Analysis:

svcxdr_decode_lock() is called by:

nlm4svc_decode_testargs()
nlm4svc_decode_lockargs()
nlm4svc_decode_cancargs()
nlm4svc_decode_unlockargs()

nlm4svc_decode_testargs() is used by:
- NLMPROC4_TEST and NLMPROC4_TEST_MSG, which call nlmsvc_retrieve_args()
- NLMPROC4_GRANTED and NLMPROC4_GRANTED_MSG, which don't pass the
  lock's file_lock to the generic lock API

nlm4svc_decode_lockargs() is used by:
- NLMPROC4_LOCK and NLM4PROC4_LOCK_MSG, which call nlmsvc_retrieve_args()
- NLMPROC4_UNLOCK and NLM4PROC4_UNLOCK_MSG, which call nlmsvc_retrieve_args()
- NLMPROC4_NM_LOCK, which calls nlmsvc_retrieve_args()

nlm4svc_decode_cancargs() is used by:
- NLMPROC4_CANCEL and NLMPROC4_CANCEL_MSG, which call nlmsvc_retrieve_args()

nlm4svc_decode_unlockargs() is used by:
- NLMPROC4_UNLOCK and NLMPROC4_UNLOCK_MSG, which call nlmsvc_retrieve_args()

All callers except GRANTED/GRANTED_MSG eventually call
nlmsvc_retrieve_args() before using nlm_lock::fl.c.flc_flags. Thus
this change is safe.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

fs/lockd/svc4proc.c

@@ -46,14 +46,15 @@ nlm4svc_retrieve_args(struct svc_rqst *rqstp, struct nlm_args *argp,
 	if (filp != NULL) {
 		int mode = lock_to_openmode(&lock->fl);
 
+		lock->fl.c.flc_flags = FL_POSIX;
+
 		error = nlm_lookup_file(rqstp, &file, lock);
 		if (error)
 			goto no_locks;
 		*filp = file;
 
 		/* Set up the missing parts of the file_lock structure */
-		lock->fl.c.flc_flags = FL_POSIX;
-		lock->fl.c.flc_file  = file->f_file[mode];
+		lock->fl.c.flc_file = file->f_file[mode];
 		lock->fl.c.flc_pid = current->tgid;
 		lock->fl.fl_start = (loff_t)lock->lock_start;
 		lock->fl.fl_end = lock->lock_len ?

fs/lockd/xdr4.c

@@ -89,7 +89,6 @@ svcxdr_decode_lock(struct xdr_stream *xdr, struct nlm_lock *lock)
 		return false;
 
 	locks_init_lock(fl);
-	fl->c.flc_flags = FL_POSIX;
 	fl->c.flc_type  = F_RDLCK;
 	nlm4svc_set_file_lock_range(fl, lock->lock_start, lock->lock_len);
 	return true;