This is a note to let you know that I've just added the patch titled

    Btrfs: fix wrong write offset when replacing a device

to the 3.10-stable tree which can be found at:
    
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     btrfs-fix-wrong-write-offset-when-replacing-a-device.patch
and it can be found in the queue-3.10 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From 115930cb2d444a684975cf2325759cb48ebf80cc Mon Sep 17 00:00:00 2001
From: Stefan Behrens <[email protected]>
Date: Thu, 4 Jul 2013 16:14:23 +0200
Subject: Btrfs: fix wrong write offset when replacing a device

From: Stefan Behrens <[email protected]>

commit 115930cb2d444a684975cf2325759cb48ebf80cc upstream.

Miao Xie reported the following issue:

The filesystem was corrupted after we did a device replace.

Steps to reproduce:
 # mkfs.btrfs -f -m single -d raid10 <device0>..<device3>
 # mount <device0> <mnt>
 # btrfs replace start -rfB 1 <device4> <mnt>
 # umount <mnt>
 # btrfsck <device4>

The reason for the issue is that we changed the write offset by mistake,
introduced by commit 625f1c8dc.

We read the data from the source device at first, and then write the
data into the corresponding place of the new device. In order to
implement the "-r" option, the source location is remapped using
btrfs_map_block(). The read takes place on the mapped location, and
the write needs to take place on the unmapped location. Currently
the write is using the mapped location, and this commit changes it
back by undoing the change to the write address that the aforementioned
commit added by mistake.

Reported-by: Miao Xie <[email protected]>
Signed-off-by: Stefan Behrens <[email protected]>
Signed-off-by: Josef Bacik <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 fs/btrfs/scrub.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -2501,7 +2501,7 @@ again:
                        ret = scrub_extent(sctx, extent_logical, extent_len,
                                           extent_physical, extent_dev, flags,
                                           generation, extent_mirror_num,
-                                          extent_physical);
+                                          extent_logical - logical + physical);
                        if (ret)
                                goto out;
 


Patches currently in stable-queue which might be from [email protected] 
are

queue-3.10/btrfs-fix-wrong-write-offset-when-replacing-a-device.patch
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