1 files changed, 107 insertions, 78 deletions

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 92303f42baaa..49d7fab73360 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -125,7 +125,7 @@ static void btrfs_kobject_uevent(struct block_device *bdev,
 
 	ret = kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, action);
 	if (ret)
-		pr_warn("Sending event '%d' to kobject: '%s' (%p): failed\n",
+		pr_warn("BTRFS: Sending event '%d' to kobject: '%s' (%p): failed\n",
 			action,
 			kobject_name(&disk_to_dev(bdev->bd_disk)->kobj),
 			&disk_to_dev(bdev->bd_disk)->kobj);
@@ -200,7 +200,7 @@ btrfs_get_bdev_and_sb(const char *device_path, fmode_t flags, void *holder,
 
 	if (IS_ERR(*bdev)) {
 		ret = PTR_ERR(*bdev);
-		printk(KERN_INFO "btrfs: open %s failed\n", device_path);
+		printk(KERN_INFO "BTRFS: open %s failed\n", device_path);
 		goto error;
 	}
 
@@ -415,7 +415,8 @@ loop_lock:
 			device->running_pending = 1;
 
 			spin_unlock(&device->io_lock);
-			btrfs_requeue_work(&device->work);
+			btrfs_queue_work(fs_info->submit_workers,
+					 &device->work);
 			goto done;
 		}
 		/* unplug every 64 requests just for good measure */
@@ -447,6 +448,14 @@ static void pending_bios_fn(struct btrfs_work *work)
 	run_scheduled_bios(device);
 }
 
+/*
+ * Add new device to list of registered devices
+ *
+ * Returns:
+ * 1   - first time device is seen
+ * 0   - device already known
+ * < 0 - error
+ */
 static noinline int device_list_add(const char *path,
 			   struct btrfs_super_block *disk_super,
 			   u64 devid, struct btrfs_fs_devices **fs_devices_ret)
@@ -454,6 +463,7 @@ static noinline int device_list_add(const char *path,
 	struct btrfs_device *device;
 	struct btrfs_fs_devices *fs_devices;
 	struct rcu_string *name;
+	int ret = 0;
 	u64 found_transid = btrfs_super_generation(disk_super);
 
 	fs_devices = find_fsid(disk_super->fsid);
@@ -494,6 +504,7 @@ static noinline int device_list_add(const char *path,
 		fs_devices->num_devices++;
 		mutex_unlock(&fs_devices->device_list_mutex);
 
+		ret = 1;
 		device->fs_devices = fs_devices;
 	} else if (!device->name || strcmp(device->name->str, path)) {
 		name = rcu_string_strdup(path, GFP_NOFS);
@@ -512,7 +523,8 @@ static noinline int device_list_add(const char *path,
 		fs_devices->latest_trans = found_transid;
 	}
 	*fs_devices_ret = fs_devices;
-	return 0;
+
+	return ret;
 }
 
 static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig)
@@ -909,17 +921,19 @@ int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
 	transid = btrfs_super_generation(disk_super);
 	total_devices = btrfs_super_num_devices(disk_super);
 
-	if (disk_super->label[0]) {
-		if (disk_super->label[BTRFS_LABEL_SIZE - 1])
-			disk_super->label[BTRFS_LABEL_SIZE - 1] = '\0';
-		printk(KERN_INFO "btrfs: device label %s ", disk_super->label);
-	} else {
-		printk(KERN_INFO "btrfs: device fsid %pU ", disk_super->fsid);
-	}
-
-	printk(KERN_CONT "devid %llu transid %llu %s\n", devid, transid, path);
-
 	ret = device_list_add(path, disk_super, devid, fs_devices_ret);
+	if (ret > 0) {
+		if (disk_super->label[0]) {
+			if (disk_super->label[BTRFS_LABEL_SIZE - 1])
+				disk_super->label[BTRFS_LABEL_SIZE - 1] = '\0';
+			printk(KERN_INFO "BTRFS: device label %s ", disk_super->label);
+		} else {
+			printk(KERN_INFO "BTRFS: device fsid %pU ", disk_super->fsid);
+		}
+
+		printk(KERN_CONT "devid %llu transid %llu %s\n", devid, transid, path);
+		ret = 0;
+	}
 	if (!ret && fs_devices_ret)
 		(*fs_devices_ret)->total_devices = total_devices;
 
@@ -1813,7 +1827,7 @@ int btrfs_find_device_missing_or_by_path(struct btrfs_root *root,
 		}
 
 		if (!*device) {
-			pr_err("btrfs: no missing device found\n");
+			btrfs_err(root->fs_info, "no missing device found");
 			return -ENOENT;
 		}
 
@@ -3052,7 +3066,7 @@ loop:
 error:
 	btrfs_free_path(path);
 	if (enospc_errors) {
-		printk(KERN_INFO "btrfs: %d enospc errors during balance\n",
+		btrfs_info(fs_info, "%d enospc errors during balance",
 		       enospc_errors);
 		if (!ret)
 			ret = -ENOSPC;
@@ -3138,8 +3152,8 @@ int btrfs_balance(struct btrfs_balance_control *bctl,
 		if (!(bctl->flags & BTRFS_BALANCE_DATA) ||
 		    !(bctl->flags & BTRFS_BALANCE_METADATA) ||
 		    memcmp(&bctl->data, &bctl->meta, sizeof(bctl->data))) {
-			printk(KERN_ERR "btrfs: with mixed groups data and "
-			       "metadata balance options must be the same\n");
+			btrfs_err(fs_info, "with mixed groups data and "
+				   "metadata balance options must be the same");
 			ret = -EINVAL;
 			goto out;
 		}
@@ -3165,8 +3179,8 @@ int btrfs_balance(struct btrfs_balance_control *bctl,
 	if ((bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
 	    (!alloc_profile_is_valid(bctl->data.target, 1) ||
 	     (bctl->data.target & ~allowed))) {
-		printk(KERN_ERR "btrfs: unable to start balance with target "
-		       "data profile %llu\n",
+		btrfs_err(fs_info, "unable to start balance with target "
+			   "data profile %llu",
 		       bctl->data.target);
 		ret = -EINVAL;
 		goto out;
@@ -3174,8 +3188,8 @@ int btrfs_balance(struct btrfs_balance_control *bctl,
 	if ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
 	    (!alloc_profile_is_valid(bctl->meta.target, 1) ||
 	     (bctl->meta.target & ~allowed))) {
-		printk(KERN_ERR "btrfs: unable to start balance with target "
-		       "metadata profile %llu\n",
+		btrfs_err(fs_info,
+			   "unable to start balance with target metadata profile %llu",
 		       bctl->meta.target);
 		ret = -EINVAL;
 		goto out;
@@ -3183,8 +3197,8 @@ int btrfs_balance(struct btrfs_balance_control *bctl,
 	if ((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
 	    (!alloc_profile_is_valid(bctl->sys.target, 1) ||
 	     (bctl->sys.target & ~allowed))) {
-		printk(KERN_ERR "btrfs: unable to start balance with target "
-		       "system profile %llu\n",
+		btrfs_err(fs_info,
+			   "unable to start balance with target system profile %llu",
 		       bctl->sys.target);
 		ret = -EINVAL;
 		goto out;
@@ -3193,7 +3207,7 @@ int btrfs_balance(struct btrfs_balance_control *bctl,
 	/* allow dup'ed data chunks only in mixed mode */
 	if (!mixed && (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
 	    (bctl->data.target & BTRFS_BLOCK_GROUP_DUP)) {
-		printk(KERN_ERR "btrfs: dup for data is not allowed\n");
+		btrfs_err(fs_info, "dup for data is not allowed");
 		ret = -EINVAL;
 		goto out;
 	}
@@ -3213,11 +3227,10 @@ int btrfs_balance(struct btrfs_balance_control *bctl,
 		     (fs_info->avail_metadata_alloc_bits & allowed) &&
 		     !(bctl->meta.target & allowed))) {
 			if (bctl->flags & BTRFS_BALANCE_FORCE) {
-				printk(KERN_INFO "btrfs: force reducing metadata "
-				       "integrity\n");
+				btrfs_info(fs_info, "force reducing metadata integrity");
 			} else {
-				printk(KERN_ERR "btrfs: balance will reduce metadata "
-				       "integrity, use force if you want this\n");
+				btrfs_err(fs_info, "balance will reduce metadata "
+					   "integrity, use force if you want this");
 				ret = -EINVAL;
 				goto out;
 			}
@@ -3303,7 +3316,7 @@ static int balance_kthread(void *data)
 	mutex_lock(&fs_info->balance_mutex);
 
 	if (fs_info->balance_ctl) {
-		printk(KERN_INFO "btrfs: continuing balance\n");
+		btrfs_info(fs_info, "continuing balance");
 		ret = btrfs_balance(fs_info->balance_ctl, NULL);
 	}
 
@@ -3325,7 +3338,7 @@ int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info)
 	spin_unlock(&fs_info->balance_lock);
 
 	if (btrfs_test_opt(fs_info->tree_root, SKIP_BALANCE)) {
-		printk(KERN_INFO "btrfs: force skipping balance\n");
+		btrfs_info(fs_info, "force skipping balance");
 		return 0;
 	}
 
@@ -3543,7 +3556,7 @@ update_tree:
 						  BTRFS_UUID_KEY_SUBVOL,
 						  key.objectid);
 			if (ret < 0) {
-				pr_warn("btrfs: uuid_tree_add failed %d\n",
+				btrfs_warn(fs_info, "uuid_tree_add failed %d",
 					ret);
 				break;
 			}
@@ -3555,7 +3568,7 @@ update_tree:
 						 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
 						  key.objectid);
 			if (ret < 0) {
-				pr_warn("btrfs: uuid_tree_add failed %d\n",
+				btrfs_warn(fs_info, "uuid_tree_add failed %d",
 					ret);
 				break;
 			}
@@ -3590,7 +3603,7 @@ out:
 	if (trans && !IS_ERR(trans))
 		btrfs_end_transaction(trans, fs_info->uuid_root);
 	if (ret)
-		pr_warn("btrfs: btrfs_uuid_scan_kthread failed %d\n", ret);
+		btrfs_warn(fs_info, "btrfs_uuid_scan_kthread failed %d", ret);
 	else
 		fs_info->update_uuid_tree_gen = 1;
 	up(&fs_info->uuid_tree_rescan_sem);
@@ -3654,7 +3667,7 @@ static int btrfs_uuid_rescan_kthread(void *data)
 	 */
 	ret = btrfs_uuid_tree_iterate(fs_info, btrfs_check_uuid_tree_entry);
 	if (ret < 0) {
-		pr_warn("btrfs: iterating uuid_tree failed %d\n", ret);
+		btrfs_warn(fs_info, "iterating uuid_tree failed %d", ret);
 		up(&fs_info->uuid_tree_rescan_sem);
 		return ret;
 	}
@@ -3695,7 +3708,7 @@ int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info)
 	task = kthread_run(btrfs_uuid_scan_kthread, fs_info, "btrfs-uuid");
 	if (IS_ERR(task)) {
 		/* fs_info->update_uuid_tree_gen remains 0 in all error case */
-		pr_warn("btrfs: failed to start uuid_scan task\n");
+		btrfs_warn(fs_info, "failed to start uuid_scan task");
 		up(&fs_info->uuid_tree_rescan_sem);
 		return PTR_ERR(task);
 	}
@@ -3711,7 +3724,7 @@ int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info)
 	task = kthread_run(btrfs_uuid_rescan_kthread, fs_info, "btrfs-uuid");
 	if (IS_ERR(task)) {
 		/* fs_info->update_uuid_tree_gen remains 0 in all error case */
-		pr_warn("btrfs: failed to start uuid_rescan task\n");
+		btrfs_warn(fs_info, "failed to start uuid_rescan task");
 		up(&fs_info->uuid_tree_rescan_sem);
 		return PTR_ERR(task);
 	}
@@ -4033,7 +4046,7 @@ static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
 		max_stripe_size = 32 * 1024 * 1024;
 		max_chunk_size = 2 * max_stripe_size;
 	} else {
-		printk(KERN_ERR "btrfs: invalid chunk type 0x%llx requested\n",
+		btrfs_err(info, "invalid chunk type 0x%llx requested\n",
 		       type);
 		BUG_ON(1);
 	}
@@ -4065,7 +4078,7 @@ static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
 
 		if (!device->writeable) {
 			WARN(1, KERN_ERR
-			       "btrfs: read-only device in alloc_list\n");
+			       "BTRFS: read-only device in alloc_list\n");
 			continue;
 		}
 
@@ -5193,13 +5206,13 @@ int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
 	read_unlock(&em_tree->lock);
 
 	if (!em) {
-		printk(KERN_ERR "btrfs: couldn't find em for chunk %Lu\n",
+		printk(KERN_ERR "BTRFS: couldn't find em for chunk %Lu\n",
 		       chunk_start);
 		return -EIO;
 	}
 
 	if (em->start != chunk_start) {
-		printk(KERN_ERR "btrfs: bad chunk start, em=%Lu, wanted=%Lu\n",
+		printk(KERN_ERR "BTRFS: bad chunk start, em=%Lu, wanted=%Lu\n",
 		       em->start, chunk_start);
 		free_extent_map(em);
 		return -EIO;
@@ -5264,6 +5277,7 @@ int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
 static void btrfs_end_bio(struct bio *bio, int err)
 {
 	struct btrfs_bio *bbio = bio->bi_private;
+	struct btrfs_device *dev = bbio->stripes[0].dev;
 	int is_orig_bio = 0;
 
 	if (err) {
@@ -5271,7 +5285,6 @@ static void btrfs_end_bio(struct bio *bio, int err)
 		if (err == -EIO || err == -EREMOTEIO) {
 			unsigned int stripe_index =
 				btrfs_io_bio(bio)->stripe_index;
-			struct btrfs_device *dev;
 
 			BUG_ON(stripe_index >= bbio->num_stripes);
 			dev = bbio->stripes[stripe_index].dev;
@@ -5293,11 +5306,20 @@ static void btrfs_end_bio(struct bio *bio, int err)
 	if (bio == bbio->orig_bio)
 		is_orig_bio = 1;
 
+	btrfs_bio_counter_dec(bbio->fs_info);
+
 	if (atomic_dec_and_test(&bbio->stripes_pending)) {
 		if (!is_orig_bio) {
 			bio_put(bio);
 			bio = bbio->orig_bio;
 		}
+
+ 		/*
+		 * We have original bio now. So increment bi_remaining to
+		 * account for it in endio
+		 */
+		atomic_inc(&bio->bi_remaining);
+
 		bio->bi_private = bbio->private;
 		bio->bi_end_io = bbio->end_io;
 		btrfs_io_bio(bio)->mirror_num = bbio->mirror_num;
@@ -5322,13 +5344,6 @@ static void btrfs_end_bio(struct bio *bio, int err)
 	}
 }
 
-struct async_sched {
-	struct bio *bio;
-	int rw;
-	struct btrfs_fs_info *info;
-	struct btrfs_work work;
-};
-
 /*
  * see run_scheduled_bios for a description of why bios are collected for
  * async submit.
@@ -5385,8 +5400,8 @@ static noinline void btrfs_schedule_bio(struct btrfs_root *root,
 	spin_unlock(&device->io_lock);
 
 	if (should_queue)
-		btrfs_queue_worker(&root->fs_info->submit_workers,
-				   &device->work);
+		btrfs_queue_work(root->fs_info->submit_workers,
+				 &device->work);
 }
 
 static int bio_size_ok(struct block_device *bdev, struct bio *bio,
@@ -5411,7 +5426,7 @@ static int bio_size_ok(struct block_device *bdev, struct bio *bio,
 	if (!q->merge_bvec_fn)
 		return 1;
 
-	bvm.bi_size = bio->bi_size - prev->bv_len;
+	bvm.bi_size = bio->bi_iter.bi_size - prev->bv_len;
 	if (q->merge_bvec_fn(q, &bvm, prev) < prev->bv_len)
 		return 0;
 	return 1;
@@ -5426,7 +5441,7 @@ static void submit_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio,
 	bio->bi_private = bbio;
 	btrfs_io_bio(bio)->stripe_index = dev_nr;
 	bio->bi_end_io = btrfs_end_bio;
-	bio->bi_sector = physical >> 9;
+	bio->bi_iter.bi_sector = physical >> 9;
 #ifdef DEBUG
 	{
 		struct rcu_string *name;
@@ -5441,6 +5456,9 @@ static void submit_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio,
 	}
 #endif
 	bio->bi_bdev = dev->bdev;
+
+	btrfs_bio_counter_inc_noblocked(root->fs_info);
+
 	if (async)
 		btrfs_schedule_bio(root, dev, rw, bio);
 	else
@@ -5464,7 +5482,7 @@ again:
 	while (bvec <= (first_bio->bi_io_vec + first_bio->bi_vcnt - 1)) {
 		if (bio_add_page(bio, bvec->bv_page, bvec->bv_len,
 				 bvec->bv_offset) < bvec->bv_len) {
-			u64 len = bio->bi_size;
+			u64 len = bio->bi_iter.bi_size;
 
 			atomic_inc(&bbio->stripes_pending);
 			submit_stripe_bio(root, bbio, bio, physical, dev_nr,
@@ -5486,7 +5504,7 @@ static void bbio_error(struct btrfs_bio *bbio, struct bio *bio, u64 logical)
 		bio->bi_private = bbio->private;
 		bio->bi_end_io = bbio->end_io;
 		btrfs_io_bio(bio)->mirror_num = bbio->mirror_num;
-		bio->bi_sector = logical >> 9;
+		bio->bi_iter.bi_sector = logical >> 9;
 		kfree(bbio);
 		bio_endio(bio, -EIO);
 	}
@@ -5497,7 +5515,7 @@ int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
 {
 	struct btrfs_device *dev;
 	struct bio *first_bio = bio;
-	u64 logical = (u64)bio->bi_sector << 9;
+	u64 logical = (u64)bio->bi_iter.bi_sector << 9;
 	u64 length = 0;
 	u64 map_length;
 	u64 *raid_map = NULL;
@@ -5506,31 +5524,41 @@ int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
 	int total_devs = 1;
 	struct btrfs_bio *bbio = NULL;
 
-	length = bio->bi_size;
+	length = bio->bi_iter.bi_size;
 	map_length = length;
 
+	btrfs_bio_counter_inc_blocked(root->fs_info);
 	ret = __btrfs_map_block(root->fs_info, rw, logical, &map_length, &bbio,
 			      mirror_num, &raid_map);
-	if (ret) /* -ENOMEM */
+	if (ret) {
+		btrfs_bio_counter_dec(root->fs_info);
 		return ret;
+	}
 
 	total_devs = bbio->num_stripes;
 	bbio->orig_bio = first_bio;
 	bbio->private = first_bio->bi_private;
 	bbio->end_io = first_bio->bi_end_io;
+	bbio->fs_info = root->fs_info;
 	atomic_set(&bbio->stripes_pending, bbio->num_stripes);
 
 	if (raid_map) {
 		/* In this case, map_length has been set to the length of
 		   a single stripe; not the whole write */
 		if (rw & WRITE) {
-			return raid56_parity_write(root, bio, bbio,
-						   raid_map, map_length);
+			ret = raid56_parity_write(root, bio, bbio,
+						  raid_map, map_length);
 		} else {
-			return raid56_parity_recover(root, bio, bbio,
-						     raid_map, map_length,
-						     mirror_num);
+			ret = raid56_parity_recover(root, bio, bbio,
+						    raid_map, map_length,
+						    mirror_num);
 		}
+		/*
+		 * FIXME, replace dosen't support raid56 yet, please fix
+		 * it in the future.
+		 */
+		btrfs_bio_counter_dec(root->fs_info);
+		return ret;
 	}
 
 	if (map_length < length) {
@@ -5572,6 +5600,7 @@ int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
 				  async_submit);
 		dev_nr++;
 	}
+	btrfs_bio_counter_dec(root->fs_info);
 	return 0;
 }
 
@@ -5660,7 +5689,7 @@ struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
 	else
 		generate_random_uuid(dev->uuid);
 
-	dev->work.func = pending_bios_fn;
+	btrfs_init_work(&dev->work, pending_bios_fn, NULL, NULL);
 
 	return dev;
 }
@@ -6123,7 +6152,8 @@ static int update_dev_stat_item(struct btrfs_trans_handle *trans,
 	BUG_ON(!path);
 	ret = btrfs_search_slot(trans, dev_root, &key, path, -1, 1);
 	if (ret < 0) {
-		printk_in_rcu(KERN_WARNING "btrfs: error %d while searching for dev_stats item for device %s!\n",
+		printk_in_rcu(KERN_WARNING "BTRFS: "
+			"error %d while searching for dev_stats item for device %s!\n",
 			      ret, rcu_str_deref(device->name));
 		goto out;
 	}
@@ -6133,7 +6163,8 @@ static int update_dev_stat_item(struct btrfs_trans_handle *trans,
 		/* need to delete old one and insert a new one */
 		ret = btrfs_del_item(trans, dev_root, path);
 		if (ret != 0) {
-			printk_in_rcu(KERN_WARNING "btrfs: delete too small dev_stats item for device %s failed %d!\n",
+			printk_in_rcu(KERN_WARNING "BTRFS: "
+				"delete too small dev_stats item for device %s failed %d!\n",
 				      rcu_str_deref(device->name), ret);
 			goto out;
 		}
@@ -6146,7 +6177,8 @@ static int update_dev_stat_item(struct btrfs_trans_handle *trans,
 		ret = btrfs_insert_empty_item(trans, dev_root, path,
 					      &key, sizeof(*ptr));
 		if (ret < 0) {
-			printk_in_rcu(KERN_WARNING "btrfs: insert dev_stats item for device %s failed %d!\n",
+			printk_in_rcu(KERN_WARNING "BTRFS: "
+					  "insert dev_stats item for device %s failed %d!\n",
 				      rcu_str_deref(device->name), ret);
 			goto out;
 		}
@@ -6199,16 +6231,14 @@ static void btrfs_dev_stat_print_on_error(struct btrfs_device *dev)
 {
 	if (!dev->dev_stats_valid)
 		return;
-	printk_ratelimited_in_rcu(KERN_ERR
-			   "btrfs: bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n",
+	printk_ratelimited_in_rcu(KERN_ERR "BTRFS: "
+			   "bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n",
 			   rcu_str_deref(dev->name),
 			   btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS),
 			   btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS),
 			   btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS),
-			   btrfs_dev_stat_read(dev,
-					       BTRFS_DEV_STAT_CORRUPTION_ERRS),
-			   btrfs_dev_stat_read(dev,
-					       BTRFS_DEV_STAT_GENERATION_ERRS));
+			   btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS),
+			   btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS));
 }
 
 static void btrfs_dev_stat_print_on_load(struct btrfs_device *dev)
@@ -6221,7 +6251,8 @@ static void btrfs_dev_stat_print_on_load(struct btrfs_device *dev)
 	if (i == BTRFS_DEV_STAT_VALUES_MAX)
 		return; /* all values == 0, suppress message */
 
-	printk_in_rcu(KERN_INFO "btrfs: bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n",
+	printk_in_rcu(KERN_INFO "BTRFS: "
+		   "bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n",
 	       rcu_str_deref(dev->name),
 	       btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS),
 	       btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS),
@@ -6242,12 +6273,10 @@ int btrfs_get_dev_stats(struct btrfs_root *root,
 	mutex_unlock(&fs_devices->device_list_mutex);
 
 	if (!dev) {
-		printk(KERN_WARNING
-		       "btrfs: get dev_stats failed, device not found\n");
+		btrfs_warn(root->fs_info, "get dev_stats failed, device not found");
 		return -ENODEV;
 	} else if (!dev->dev_stats_valid) {
-		printk(KERN_WARNING
-		       "btrfs: get dev_stats failed, not yet valid\n");
+		btrfs_warn(root->fs_info, "get dev_stats failed, not yet valid");
 		return -ENODEV;
 	} else if (stats->flags & BTRFS_DEV_STATS_RESET) {
 		for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) {