bcache: rework error unwinding in register_bcache

[tomoyo/tomoyo-test1.git] / drivers / md / bcache / super.c

diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index 3045f27..e8013e1 100644 (file)
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -2375,29 +2375,33 @@ static bool bch_is_open(struct block_device *bdev)
 static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
                               const char *buffer, size_t size)
 {
-       ssize_t ret = -EINVAL;
-       const char *err = "cannot allocate memory";
-       char *path = NULL;
-       struct cache_sb *sb = NULL;
+       const char *err;
+       char *path;
+       struct cache_sb *sb;
        struct block_device *bdev = NULL;
-       struct page *sb_page = NULL;
+       struct page *sb_page;
+       ssize_t ret;
 
+       ret = -EBUSY;
        if (!try_module_get(THIS_MODULE))
-               return -EBUSY;
+               goto out;
 
        /* For latest state of bcache_is_reboot */
        smp_mb();
        if (bcache_is_reboot)
-               return -EBUSY;
+               goto out_module_put;
 
+       ret = -ENOMEM;
+       err = "cannot allocate memory";
        path = kstrndup(buffer, size, GFP_KERNEL);
        if (!path)
-               goto err;
+               goto out_module_put;
 
        sb = kmalloc(sizeof(struct cache_sb), GFP_KERNEL);
        if (!sb)
-               goto err;
+               goto out_free_path;
 
+       ret = -EINVAL;
        err = "failed to open device";
        bdev = blkdev_get_by_path(strim(path),
                                  FMODE_READ|FMODE_WRITE|FMODE_EXCL,
@@ -2414,57 +2418,68 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
                        if (!IS_ERR(bdev))
                                bdput(bdev);
                        if (attr == &ksysfs_register_quiet)
-                               goto quiet_out;
+                               goto done;
                }
-               goto err;
+               goto out_free_sb;
        }
 
        err = "failed to set blocksize";
        if (set_blocksize(bdev, 4096))
-               goto err_close;
+               goto out_blkdev_put;
 
        err = read_super(sb, bdev, &sb_page);
        if (err)
-               goto err_close;
+               goto out_blkdev_put;
 
        err = "failed to register device";
        if (SB_IS_BDEV(sb)) {
                struct cached_dev *dc = kzalloc(sizeof(*dc), GFP_KERNEL);
 
                if (!dc)
-                       goto err_close;
+                       goto out_put_sb_page;
 
                mutex_lock(&bch_register_lock);
                ret = register_bdev(sb, sb_page, bdev, dc);
                mutex_unlock(&bch_register_lock);
                /* blkdev_put() will be called in cached_dev_free() */
-               if (ret < 0)
-                       goto err;
+               if (ret < 0) {
+                       bdev = NULL;
+                       goto out_put_sb_page;
+               }
        } else {
                struct cache *ca = kzalloc(sizeof(*ca), GFP_KERNEL);
 
                if (!ca)
-                       goto err_close;
+                       goto out_put_sb_page;
 
                /* blkdev_put() will be called in bch_cache_release() */
-               if (register_cache(sb, sb_page, bdev, ca) != 0)
-                       goto err;
+               if (register_cache(sb, sb_page, bdev, ca) != 0) {
+                       bdev = NULL;
+                       goto out_put_sb_page;
+               }
        }
-quiet_out:
-       ret = size;
-out:
-       if (sb_page)
-               put_page(sb_page);
+
+       put_page(sb_page);
+done:
        kfree(sb);
        kfree(path);
        module_put(THIS_MODULE);
-       return ret;
-
-err_close:
-       blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
-err:
+       return size;
+
+out_put_sb_page:
+       put_page(sb_page);
+out_blkdev_put:
+       if (bdev)
+               blkdev_put(bdev, FMODE_READ | FMODE_WRITE | FMODE_EXCL);
+out_free_sb:
+       kfree(sb);
+out_free_path:
+       kfree(path);
+out_module_put:
+       module_put(THIS_MODULE);
+out:
        pr_info("error %s: %s", path, err);
-       goto out;
+       return ret;
 }