bcache: remove the backing_dev_name field from struct cached_dev

Just use the %pg format specifier to print the name directly.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Coly Li <colyli@suse.de>
Link: https://lore.kernel.org/r/20211020143812.6403-7-colyli@suse.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

drivers/md/bcache/bcache.h

@@ -395,8 +395,6 @@ struct cached_dev {
 	atomic_t		io_errors;
 	unsigned int		error_limit;
 	unsigned int		offline_seconds;
-
-	char			backing_dev_name[BDEVNAME_SIZE];
 };
 
 enum alloc_reserve {

drivers/md/bcache/debug.c

@@ -137,8 +137,8 @@ void bch_data_verify(struct cached_dev *dc, struct bio *bio)
 					p2 + bv.bv_offset,
 					bv.bv_len),
 				 dc->disk.c,
-				 "verify failed at dev %s sector %llu",
-				 dc->backing_dev_name,
+				 "verify failed at dev %pg sector %llu",
+				 dc->bdev,
 				 (uint64_t) bio->bi_iter.bi_sector);
 
 		kunmap_atomic(p1);

drivers/md/bcache/io.c

@@ -65,15 +65,15 @@ void bch_count_backing_io_errors(struct cached_dev *dc, struct bio *bio)
 	 * we shouldn't count failed REQ_RAHEAD bio to dc->io_errors.
 	 */
 	if (bio->bi_opf & REQ_RAHEAD) {
-		pr_warn_ratelimited("%s: Read-ahead I/O failed on backing device, ignore\n",
-				    dc->backing_dev_name);
+		pr_warn_ratelimited("%pg: Read-ahead I/O failed on backing device, ignore\n",
+				    dc->bdev);
 		return;
 	}
 
 	errors = atomic_add_return(1, &dc->io_errors);
 	if (errors < dc->error_limit)
-		pr_err("%s: IO error on backing device, unrecoverable\n",
-			dc->backing_dev_name);
+		pr_err("%pg: IO error on backing device, unrecoverable\n",
+			dc->bdev);
 	else
 		bch_cached_dev_error(dc);
 }

drivers/md/bcache/request.c

@@ -651,8 +651,8 @@ static void backing_request_endio(struct bio *bio)
 		 */
 		if (unlikely(s->iop.writeback &&
 			     bio->bi_opf & REQ_PREFLUSH)) {
-			pr_err("Can't flush %s: returned bi_status %i\n",
-				dc->backing_dev_name, bio->bi_status);
+			pr_err("Can't flush %pg: returned bi_status %i\n",
+				dc->bdev, bio->bi_status);
 		} else {
 			/* set to orig_bio->bi_status in bio_complete() */
 			s->iop.status = bio->bi_status;

drivers/md/bcache/super.c

@@ -1026,8 +1026,8 @@ static int cached_dev_status_update(void *arg)
 			dc->offline_seconds = 0;
 
 		if (dc->offline_seconds >= BACKING_DEV_OFFLINE_TIMEOUT) {
-			pr_err("%s: device offline for %d seconds\n",
-			       dc->backing_dev_name,
+			pr_err("%pg: device offline for %d seconds\n",
+			       dc->bdev,
 			       BACKING_DEV_OFFLINE_TIMEOUT);
 			pr_err("%s: disable I/O request due to backing device offline\n",
 			       dc->disk.name);
@@ -1058,15 +1058,13 @@ int bch_cached_dev_run(struct cached_dev *dc)
 	};
 
 	if (dc->io_disable) {
-		pr_err("I/O disabled on cached dev %s\n",
-		       dc->backing_dev_name);
+		pr_err("I/O disabled on cached dev %pg\n", dc->bdev);
 		ret = -EIO;
 		goto out;
 	}
 
 	if (atomic_xchg(&dc->running, 1)) {
-		pr_info("cached dev %s is running already\n",
-		       dc->backing_dev_name);
+		pr_info("cached dev %pg is running already\n", dc->bdev);
 		ret = -EBUSY;
 		goto out;
 	}
@@ -1163,7 +1161,7 @@ static void cached_dev_detach_finish(struct work_struct *w)
 
 	mutex_unlock(&bch_register_lock);
 
-	pr_info("Caching disabled for %s\n", dc->backing_dev_name);
+	pr_info("Caching disabled for %pg\n", dc->bdev);
 
 	/* Drop ref we took in cached_dev_detach() */
 	closure_put(&dc->disk.cl);
@@ -1203,29 +1201,27 @@ int bch_cached_dev_attach(struct cached_dev *dc, struct cache_set *c,
 		return -ENOENT;
 
 	if (dc->disk.c) {
-		pr_err("Can't attach %s: already attached\n",
-		       dc->backing_dev_name);
+		pr_err("Can't attach %pg: already attached\n", dc->bdev);
 		return -EINVAL;
 	}
 
 	if (test_bit(CACHE_SET_STOPPING, &c->flags)) {
-		pr_err("Can't attach %s: shutting down\n",
-		       dc->backing_dev_name);
+		pr_err("Can't attach %pg: shutting down\n", dc->bdev);
 		return -EINVAL;
 	}
 
 	if (dc->sb.block_size < c->cache->sb.block_size) {
 		/* Will die */
-		pr_err("Couldn't attach %s: block size less than set's block size\n",
-		       dc->backing_dev_name);
+		pr_err("Couldn't attach %pg: block size less than set's block size\n",
+		       dc->bdev);
 		return -EINVAL;
 	}
 
 	/* Check whether already attached */
 	list_for_each_entry_safe(exist_dc, t, &c->cached_devs, list) {
 		if (!memcmp(dc->sb.uuid, exist_dc->sb.uuid, 16)) {
-			pr_err("Tried to attach %s but duplicate UUID already attached\n",
-				dc->backing_dev_name);
+			pr_err("Tried to attach %pg but duplicate UUID already attached\n",
+				dc->bdev);
 
 			return -EINVAL;
 		}
@@ -1243,15 +1239,13 @@ int bch_cached_dev_attach(struct cached_dev *dc, struct cache_set *c,
 
 	if (!u) {
 		if (BDEV_STATE(&dc->sb) == BDEV_STATE_DIRTY) {
-			pr_err("Couldn't find uuid for %s in set\n",
-			       dc->backing_dev_name);
+			pr_err("Couldn't find uuid for %pg in set\n", dc->bdev);
 			return -ENOENT;
 		}
 
 		u = uuid_find_empty(c);
 		if (!u) {
-			pr_err("Not caching %s, no room for UUID\n",
-			       dc->backing_dev_name);
+			pr_err("Not caching %pg, no room for UUID\n", dc->bdev);
 			return -EINVAL;
 		}
 	}
@@ -1319,8 +1313,7 @@ int bch_cached_dev_attach(struct cached_dev *dc, struct cache_set *c,
 		 */
 		kthread_stop(dc->writeback_thread);
 		cancel_writeback_rate_update_dwork(dc);
-		pr_err("Couldn't run cached device %s\n",
-		       dc->backing_dev_name);
+		pr_err("Couldn't run cached device %pg\n", dc->bdev);
 		return ret;
 	}
 
@@ -1336,8 +1329,8 @@ int bch_cached_dev_attach(struct cached_dev *dc, struct cache_set *c,
 	/* Allow the writeback thread to proceed */
 	up_write(&dc->writeback_lock);
 
-	pr_info("Caching %s as %s on set %pU\n",
-		dc->backing_dev_name,
+	pr_info("Caching %pg as %s on set %pU\n",
+		dc->bdev,
 		dc->disk.disk->disk_name,
 		dc->disk.c->set_uuid);
 	return 0;
@@ -1461,7 +1454,6 @@ static int register_bdev(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
 	struct cache_set *c;
 	int ret = -ENOMEM;
 
-	bdevname(bdev, dc->backing_dev_name);
 	memcpy(&dc->sb, sb, sizeof(struct cache_sb));
 	dc->bdev = bdev;
 	dc->bdev->bd_holder = dc;
@@ -1476,7 +1468,7 @@ static int register_bdev(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
 	if (bch_cache_accounting_add_kobjs(&dc->accounting, &dc->disk.kobj))
 		goto err;
 
-	pr_info("registered backing device %s\n", dc->backing_dev_name);
+	pr_info("registered backing device %pg\n", dc->bdev);
 
 	list_add(&dc->list, &uncached_devices);
 	/* attach to a matched cache set if it exists */
@@ -1493,7 +1485,7 @@ static int register_bdev(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
 
 	return 0;
 err:
-	pr_notice("error %s: %s\n", dc->backing_dev_name, err);
+	pr_notice("error %pg: %s\n", dc->bdev, err);
 	bcache_device_stop(&dc->disk);
 	return ret;
 }
@@ -1621,8 +1613,8 @@ bool bch_cached_dev_error(struct cached_dev *dc)
 	/* make others know io_disable is true earlier */
 	smp_mb();
 
-	pr_err("stop %s: too many IO errors on backing device %s\n",
-	       dc->disk.disk->disk_name, dc->backing_dev_name);
+	pr_err("stop %s: too many IO errors on backing device %pg\n",
+	       dc->disk.disk->disk_name, dc->bdev);
 
 	bcache_device_stop(&dc->disk);
 	return true;

drivers/md/bcache/sysfs.c

@@ -271,7 +271,7 @@ SHOW(__bch_cached_dev)
 	}
 
 	if (attr == &sysfs_backing_dev_name) {
-		snprintf(buf, BDEVNAME_SIZE + 1, "%s", dc->backing_dev_name);
+		snprintf(buf, BDEVNAME_SIZE + 1, "%pg", dc->bdev);
 		strcat(buf, "\n");
 		return strlen(buf);
 	}