lockd: rip out deferred lock handling from testlock codepath

As Kinglong points out, the nlm_block->b_fl field is no longer used at all. Also, vfs_test_lock in the generic locking code will only return FILE_LOCK_DEFERRED if FL_SLEEP is set, and it isn't here. The only other place that returns that value is the DLM lock code, but it only does that in dlm_posix_lock, never in dlm_posix_get. Remove all of the deferred locking code from the testlock codepath since it doesn't appear to ever be used anyway. I do have a small concern that this might cause a behavior change in the case where you have a block already sitting on the list when the testlock request comes in, but that looks like it doesn't really work properly anyway. I think it's best to just pass that down to vfs_test_lock and let the filesystem report that instead of trying to infer what's going on with the lock by looking at an existing block.

Jeff Layton committed 12 years ago

Commit 09802fd1 parent aef95832 files · +6 −50Browse files

Unified · Split

2 files

fs/lockd/svclock.c +6 −49
include/linux/lockd/lockd.h +0 −1

fs/lockd/svclock.c+6−49

 	block->b_daemon = rqstp->rq_server;
 	block->b_host   = host;
 	block->b_file   = file;
-	block->b_fl = NULL;
 	file->f_count++;
 	/* Add to file's list of blocks */
 	nlmsvc_freegrantargs(block->b_call);
 	nlmsvc_release_call(block->b_call);
 	nlm_release_file(block->b_file);
-	kfree(block->b_fl);
 	kfree(block);
 }
 		struct nlm_host *host, struct nlm_lock *lock,
 		struct nlm_lock *conflock, struct nlm_cookie *cookie)
 {
-	struct nlm_block 	*block = NULL;
 	int			error;
 	__be32			ret;
 				(long long)lock->fl.fl_start,
 				(long long)lock->fl.fl_end);
-	/* Get existing block (in case client is busy-waiting) */
-	block = nlmsvc_lookup_block(file, lock);
-	if (block == NULL) {
-		struct file_lock *conf = kzalloc(sizeof(*conf), GFP_KERNEL);
-		if (conf == NULL)
-			return nlm_granted;
-		block = nlmsvc_create_block(rqstp, host, file, lock, cookie);
-		if (block == NULL) {
-			kfree(conf);
-			return nlm_granted;
-		}
-		block->b_fl = conf;
-	}
-	if (block->b_flags & B_QUEUED) {
-		dprintk("lockd: nlmsvc_testlock deferred block %p flags %d fl %p\n",
-			block, block->b_flags, block->b_fl);
-		if (block->b_flags & B_TIMED_OUT) {
-			nlmsvc_unlink_block(block);
-			ret = nlm_lck_denied;
-			goto out;
-		}
-		if (block->b_flags & B_GOT_CALLBACK) {
-			nlmsvc_unlink_block(block);
-			if (block->b_fl != NULL
-					&& block->b_fl->fl_type != F_UNLCK) {
-				lock->fl = *block->b_fl;
-				goto conf_lock;
-			} else {
-				ret = nlm_granted;
-				goto out;
-			}
-		}
-		ret = nlm_drop_reply;
-		goto out;
-	}
 	if (locks_in_grace(SVC_NET(rqstp))) {
 		ret = nlm_lck_denied_grace_period;
 		goto out;
 	}
 	error = vfs_test_lock(file->f_file, &lock->fl);
-	if (error == FILE_LOCK_DEFERRED) {
-		ret = nlmsvc_defer_lock_rqst(rqstp, block);
-		goto out;
-	}
 	if (error) {
+		/* We can't currently deal with deferred test requests */
+		if (error == FILE_LOCK_DEFERRED)
+			WARN_ON_ONCE(1);
 		ret = nlm_lck_denied_nolocks;
 		goto out;
 	}
 	if (lock->fl.fl_type == F_UNLCK) {
 		ret = nlm_granted;
 		goto out;
 	}
-conf_lock:
 	dprintk("lockd: conflicting lock(ty=%d, %Ld-%Ld)\n",
 		lock->fl.fl_type, (long long)lock->fl.fl_start,
 		(long long)lock->fl.fl_end);
 	locks_release_private(&lock->fl);
 	ret = nlm_lck_denied;
 out:
-	if (block)
-		nlmsvc_release_block(block);
 	return ret;
 }
  * This is a callback from the filesystem for VFS file lock requests.
  * It will be used if lm_grant is defined and the filesystem can not
  * respond to the request immediately.
- * For GETLK request it will copy the reply to the nlm_block.
  * For SETLK or SETLKW request it will get the local posix lock.
  * In all cases it will move the block to the head of nlm_blocked q where
  * nlmsvc_retry_blocked() can send back a reply for SETLKW or revisit the

include/linux/lockd/lockd.h+0−1

@@ -178,7 +178,6 @@ struct nlm_block { · 177 unmodified lines
178	unsigned char b_granted; /* VFS granted lock */	178	unsigned char b_granted; /* VFS granted lock */
179	struct nlm_file * b_file; /* file in question */	179	struct nlm_file * b_file; /* file in question */
180	struct cache_req * b_cache_req; /* deferred request handling */	180	struct cache_req * b_cache_req; /* deferred request handling */
181	struct file_lock * b_fl; /* set for GETLK */
182	struct cache_deferred_req * b_deferred_req;	181	struct cache_deferred_req * b_deferred_req;
183	unsigned int b_flags; /* block flags */	182	unsigned int b_flags; /* block flags */
184	#define B_QUEUED 1 /* lock queued */	183	#define B_QUEUED 1 /* lock queued */