[PATCH] device-mapper: rename frozen_bdev

Rename frozen_bdev to suspended_bdev and move the bdget outside lockfs.  (This
prepares for making lockfs optional.)

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 9e8c1edd89dd3386a96827a43c1dd8c5262bca79..fc335e09d0727b8d62e7679459acbe3248012d38 100644 (file)
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -97,7 +97,7 @@ struct mapped_device {
         * freeze/thaw support require holding onto a super block
         */
        struct super_block *frozen_sb;
-       struct block_device *frozen_bdev;
+       struct block_device *suspended_bdev;
 };
 
 #define MIN_IOS 256
@@ -836,9 +836,9 @@ static void __set_size(struct mapped_device *md, sector_t size)
 {
        set_capacity(md->disk, size);
 
-       down(&md->frozen_bdev->bd_inode->i_sem);
-       i_size_write(md->frozen_bdev->bd_inode, (loff_t)size << SECTOR_SHIFT);
-       up(&md->frozen_bdev->bd_inode->i_sem);
+       down(&md->suspended_bdev->bd_inode->i_sem);
+       i_size_write(md->suspended_bdev->bd_inode, (loff_t)size << SECTOR_SHIFT);
+       up(&md->suspended_bdev->bd_inode->i_sem);
 }
 
 static int __bind(struct mapped_device *md, struct dm_table *t)
@@ -1010,43 +1010,27 @@ out:
  */
 static int lock_fs(struct mapped_device *md)
 {
-       int r = -ENOMEM;
-
-       md->frozen_bdev = bdget_disk(md->disk, 0);
-       if (!md->frozen_bdev) {
-               DMWARN("bdget failed in lock_fs");
-               goto out;
-       }
+       int r;
 
        WARN_ON(md->frozen_sb);
 
-       md->frozen_sb = freeze_bdev(md->frozen_bdev);
+       md->frozen_sb = freeze_bdev(md->suspended_bdev);
        if (IS_ERR(md->frozen_sb)) {
                r = PTR_ERR(md->frozen_sb);
-               goto out_bdput;
+               md->frozen_sb = NULL;
+               return r;
        }
 
        /* don't bdput right now, we don't want the bdev
-        * to go away while it is locked.  We'll bdput
-        * in unlock_fs
+        * to go away while it is locked.
         */
        return 0;
-
-out_bdput:
-       bdput(md->frozen_bdev);
-       md->frozen_sb = NULL;
-       md->frozen_bdev = NULL;
-out:
-       return r;
 }
 
 static void unlock_fs(struct mapped_device *md)
 {
-       thaw_bdev(md->frozen_bdev, md->frozen_sb);
-       bdput(md->frozen_bdev);
-
+       thaw_bdev(md->suspended_bdev, md->frozen_sb);
        md->frozen_sb = NULL;
-       md->frozen_bdev = NULL;
 }
 
 /*
@@ -1072,6 +1056,13 @@ int dm_suspend(struct mapped_device *md)
        /* This does not get reverted if there's an error later. */
        dm_table_presuspend_targets(map);
 
+       md->suspended_bdev = bdget_disk(md->disk, 0);
+       if (!md->suspended_bdev) {
+               DMWARN("bdget failed in dm_suspend");
+               r = -ENOMEM;
+               goto out;
+       }
+
        /* Flush I/O to the device. */
        r = lock_fs(md);
        if (r)
@@ -1124,6 +1115,11 @@ int dm_suspend(struct mapped_device *md)
        r = 0;
 
 out:
+       if (r && md->suspended_bdev) {
+               bdput(md->suspended_bdev);
+               md->suspended_bdev = NULL;
+       }
+
        dm_table_put(map);
        up(&md->suspend_lock);
        return r;
@@ -1154,6 +1150,9 @@ int dm_resume(struct mapped_device *md)
 
        unlock_fs(md);
 
+       bdput(md->suspended_bdev);
+       md->suspended_bdev = NULL;
+
        clear_bit(DMF_SUSPENDED, &md->flags);
 
        dm_table_unplug_all(map);