dm: push error reporting down to dm_register_target()

Simplifies each DM target's init method by making dm_register_target()
responsible for its error reporting (on behalf of targets).

Signed-off-by: Yangtao Li <frank.li@vivo.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

drivers/md/dm-cache-target.c

@@ -3459,7 +3459,6 @@ static int __init dm_cache_init(void)
 
 	r = dm_register_target(&cache_target);
 	if (r) {
-		DMERR("cache target registration failed: %d", r);
 		kmem_cache_destroy(migration_cache);
 		return r;
 	}

drivers/md/dm-clone-target.c

@@ -2204,7 +2204,6 @@ static int __init dm_clone_init(void)
 
 	r = dm_register_target(&clone_target);
 	if (r < 0) {
-		DMERR("Failed to register clone target");
 		kmem_cache_destroy(_hydration_cache);
 		return r;
 	}

drivers/md/dm-crypt.c

@@ -3662,13 +3662,7 @@ static struct target_type crypt_target = {
 
 static int __init dm_crypt_init(void)
 {
-	int r;
+	return dm_register_target(&crypt_target);
-
-	r = dm_register_target(&crypt_target);
-	if (r < 0)
-		DMERR("register failed %d", r);
-
-	return r;
 }
 
 static void __exit dm_crypt_exit(void)

drivers/md/dm-delay.c

@@ -370,18 +370,7 @@ static struct target_type delay_target = {
 
 static int __init dm_delay_init(void)
 {
-	int r;
+	return dm_register_target(&delay_target);
-
-	r = dm_register_target(&delay_target);
-	if (r < 0) {
-		DMERR("register failed %d", r);
-		goto bad_register;
-	}
-
-	return 0;
-
-bad_register:
-	return r;
 }
 
 static void __exit dm_delay_exit(void)

drivers/md/dm-dust.c

@@ -573,12 +573,7 @@ static struct target_type dust_target = {
 
 static int __init dm_dust_init(void)
 {
-	int r = dm_register_target(&dust_target);
+	return dm_register_target(&dust_target);
-
-	if (r < 0)
-		DMERR("dm_register_target failed %d", r);
-
-	return r;
 }
 
 static void __exit dm_dust_exit(void)

drivers/md/dm-ebs-target.c

@@ -455,12 +455,7 @@ static struct target_type ebs_target = {
 
 static int __init dm_ebs_init(void)
 {
-	int r = dm_register_target(&ebs_target);
+	return dm_register_target(&ebs_target);
-
-	if (r < 0)
-		DMERR("register failed %d", r);
-
-	return r;
 }
 
 static void dm_ebs_exit(void)

drivers/md/dm-era-target.c

@@ -1756,15 +1756,7 @@ static struct target_type era_target = {
 
 static int __init dm_era_init(void)
 {
-	int r;
+	return dm_register_target(&era_target);
-
-	r = dm_register_target(&era_target);
-	if (r) {
-		DMERR("era target registration failed: %d", r);
-		return r;
-	}
-
-	return 0;
 }
 
 static void __exit dm_era_exit(void)

drivers/md/dm-flakey.c

@@ -509,12 +509,7 @@ static struct target_type flakey_target = {
 
 static int __init dm_flakey_init(void)
 {
-	int r = dm_register_target(&flakey_target);
+	return dm_register_target(&flakey_target);
-
-	if (r < 0)
-		DMERR("register failed %d", r);
-
-	return r;
 }
 
 static void __exit dm_flakey_exit(void)

drivers/md/dm-integrity.c

@@ -4704,7 +4704,6 @@ static int __init dm_integrity_init(void)
 
 	r = dm_register_target(&integrity_target);
 	if (r < 0) {
-		DMERR("register failed %d", r);
 		kmem_cache_destroy(journal_io_cache);
 		return r;
 	}

drivers/md/dm-log-writes.c

@@ -940,12 +940,7 @@ static struct target_type log_writes_target = {
 
 static int __init dm_log_writes_init(void)
 {
-	int r = dm_register_target(&log_writes_target);
+	return dm_register_target(&log_writes_target);
-
-	if (r < 0)
-		DMERR("register failed %d", r);
-
-	return r;
 }
 
 static void __exit dm_log_writes_exit(void)

drivers/md/dm-mpath.c

@@ -2235,11 +2235,8 @@ static int __init dm_multipath_init(void)
 	}
 
 	r = dm_register_target(&multipath_target);
-	if (r < 0) {
+	if (r < 0)
-		DMERR("request-based register failed %d", r);
-		r = -EINVAL;
 		goto bad_register_target;
-	}
 
 	return 0;
 

drivers/md/dm-raid1.c

@@ -1498,23 +1498,19 @@ static struct target_type mirror_target = {
 
 static int __init dm_mirror_init(void)
 {
-	int r = -ENOMEM;
+	int r;
 
 	dm_raid1_wq = alloc_workqueue("dm_raid1_wq", 0, 0);
 	if (!dm_raid1_wq)
-		goto bad_target;
+		return -ENOMEM;
 
 	r = dm_register_target(&mirror_target);
 	if (r < 0) {
 		destroy_workqueue(dm_raid1_wq);
-		goto bad_target;
+		return r;
 	}
 
 	return 0;
-
-bad_target:
-	DMERR("Failed to register mirror target");
-	return r;
 }
 
 static void __exit dm_mirror_exit(void)

drivers/md/dm-snap.c

@@ -2815,22 +2815,16 @@ static int __init dm_snapshot_init(void)
 	}
 
 	r = dm_register_target(&snapshot_target);
-	if (r < 0) {
+	if (r < 0)
-		DMERR("snapshot target register failed %d", r);
 		goto bad_register_snapshot_target;
-	}
 
 	r = dm_register_target(&origin_target);
-	if (r < 0) {
+	if (r < 0)
-		DMERR("Origin target register failed %d", r);
 		goto bad_register_origin_target;
-	}
 
 	r = dm_register_target(&merge_target);
-	if (r < 0) {
+	if (r < 0)
-		DMERR("Merge target register failed %d", r);
 		goto bad_register_merge_target;
-	}
 
 	return 0;
 

drivers/md/dm-switch.c

@@ -568,13 +568,7 @@ static struct target_type switch_target = {
 
 static int __init dm_switch_init(void)
 {
-	int r;
+	return dm_register_target(&switch_target);
-
-	r = dm_register_target(&switch_target);
-	if (r < 0)
-		DMERR("dm_register_target() failed %d", r);
-
-	return r;
 }
 
 static void __exit dm_switch_exit(void)

drivers/md/dm-target.c

@@ -85,12 +85,15 @@ int dm_register_target(struct target_type *tt)
 	int rv = 0;
 
 	down_write(&_lock);
-	if (__find_target_type(tt->name))
+	if (__find_target_type(tt->name)) {
+		DMERR("%s: '%s' target already registered",
+		      __func__, tt->name);
 		rv = -EEXIST;
-	else
+	} else {
 		list_add(&tt->list, &_targets);
-
+	}
 	up_write(&_lock);
+
 	return rv;
 }
 EXPORT_SYMBOL(dm_register_target);

drivers/md/dm-verity-target.c

@@ -1517,13 +1517,7 @@ static struct target_type verity_target = {
 
 static int __init dm_verity_init(void)
 {
-	int r;
+	return dm_register_target(&verity_target);
-
-	r = dm_register_target(&verity_target);
-	if (r < 0)
-		DMERR("register failed %d", r);
-
-	return r;
 }
 
 static void __exit dm_verity_exit(void)

drivers/md/dm-writecache.c

@@ -2776,15 +2776,7 @@ static struct target_type writecache_target = {
 
 static int __init dm_writecache_init(void)
 {
-	int r;
+	return dm_register_target(&writecache_target);
-
-	r = dm_register_target(&writecache_target);
-	if (r < 0) {
-		DMERR("register failed %d", r);
-		return r;
-	}
-
-	return 0;
 }
 
 static void __exit dm_writecache_exit(void)

drivers/md/dm-zero.c

@@ -78,12 +78,7 @@ static struct target_type zero_target = {
 
 static int __init dm_zero_init(void)
 {
-	int r = dm_register_target(&zero_target);
+	return dm_register_target(&zero_target);
-
-	if (r < 0)
-		DMERR("register failed %d", r);
-
-	return r;
 }
 
 static void __exit dm_zero_exit(void)