1 files changed, 21 insertions, 6 deletions

diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index 4d1d8dfb2d2a..f2273143b3cb 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -963,6 +963,7 @@ int bch_cached_dev_attach(struct cached_dev *dc, struct cache_set *c,
         uint32_t rtime = cpu_to_le32(get_seconds());
         struct uuid_entry *u;
         char buf[BDEVNAME_SIZE];
+        struct cached_dev *exist_dc, *t;
 
         bdevname(dc->bdev, buf);
 
@@ -987,6 +988,16 @@ int bch_cached_dev_attach(struct cached_dev *dc, struct cache_set *c,
                 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",
+                                buf);
+
+                        return -EINVAL;
+                }
+        }
+
         u = uuid_find(c, dc->sb.uuid);
 
         if (u &&
@@ -1204,7 +1215,7 @@ static void register_bdev(struct cache_sb *sb, struct page *sb_page,
 
         return;
 err:
-        pr_notice("error opening %s: %s", bdevname(bdev, name), err);
+        pr_notice("error %s: %s", bdevname(bdev, name), err);
         bcache_device_stop(&dc->disk);
 }
 
@@ -1883,6 +1894,8 @@ static int register_cache(struct cache_sb *sb, struct page *sb_page,
         const char *err = NULL; /* must be set for any error case */
         int ret = 0;
 
+        bdevname(bdev, name);
+
         memcpy(&ca->sb, sb, sizeof(struct cache_sb));
         ca->bdev = bdev;
         ca->bdev->bd_holder = ca;
@@ -1891,11 +1904,12 @@ static int register_cache(struct cache_sb *sb, struct page *sb_page,
         bio_first_bvec_all(&ca->sb_bio)->bv_page = sb_page;
         get_page(sb_page);
 
-        if (blk_queue_discard(bdev_get_queue(ca->bdev)))
+        if (blk_queue_discard(bdev_get_queue(bdev)))
                 ca->discard = CACHE_DISCARD(&ca->sb);
 
         ret = cache_alloc(ca);
         if (ret != 0) {
+                blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
                 if (ret == -ENOMEM)
                         err = "cache_alloc(): -ENOMEM";
                 else
@@ -1918,14 +1932,14 @@ static int register_cache(struct cache_sb *sb, struct page *sb_page,
                 goto out;
         }
 
-        pr_info("registered cache device %s", bdevname(bdev, name));
+        pr_info("registered cache device %s", name);
 
 out:
         kobject_put(&ca->kobj);
 
 err:
         if (err)
-                pr_notice("error opening %s: %s", bdevname(bdev, name), err);
+                pr_notice("error %s: %s", name, err);
 
         return ret;
 }
@@ -2014,6 +2028,7 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
         if (err)
                 goto err_close;
 
+        err = "failed to register device";
         if (SB_IS_BDEV(sb)) {
                 struct cached_dev *dc = kzalloc(sizeof(*dc), GFP_KERNEL);
                 if (!dc)
@@ -2028,7 +2043,7 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
                         goto err_close;
 
                 if (register_cache(sb, sb_page, bdev, ca) != 0)
-                        goto err_close;
+                        goto err;
         }
 out:
         if (sb_page)
@@ -2041,7 +2056,7 @@ out:
 err_close:
         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
 err:
-        pr_info("error opening %s: %s", path, err);
+        pr_info("error %s: %s", path, err);
         ret = -EINVAL;
         goto out;
 }