block: simplify the restart case in __blkdev_get

Insted of duplicating all the cleanup logic jump to the code that cleans
up anyway, and restart after that.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/fs/block_dev.c b/fs/block_dev.c
index a36d5b6..3768322 100644 (file)
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -1517,7 +1517,7 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
        int ret;
        int partno;
        int perm = 0;
-       bool first_open = false;
+       bool first_open = false, need_restart;
 
        if (mode & FMODE_READ)
                perm |= MAY_READ;
@@ -1533,7 +1533,7 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
        }
 
  restart:
-
+       need_restart = false;
        ret = -ENXIO;
        disk = bdev_get_gendisk(bdev, &partno);
        if (!disk)
@@ -1556,19 +1556,12 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
                        ret = 0;
                        if (disk->fops->open) {
                                ret = disk->fops->open(bdev, mode);
-                               if (ret == -ERESTARTSYS) {
-                                       /* Lost a race with 'disk' being
-                                        * deleted, try again.
-                                        * See md.c
-                                        */
-                                       disk_put_part(bdev->bd_part);
-                                       bdev->bd_part = NULL;
-                                       bdev->bd_disk = NULL;
-                                       mutex_unlock(&bdev->bd_mutex);
-                                       disk_unblock_events(disk);
-                                       put_disk_and_module(disk);
-                                       goto restart;
-                               }
+                               /*
+                                * If we lost a race with 'disk' being deleted,
+                                * try again.  See md.c
+                                */
+                               if (ret == -ERESTARTSYS)
+                                       need_restart = true;
                        }
 
                        if (!ret) {
@@ -1647,6 +1640,8 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
        mutex_unlock(&bdev->bd_mutex);
        disk_unblock_events(disk);
        put_disk_and_module(disk);
+       if (need_restart)
+               goto restart;
  out:
 
        return ret;