Re: [3.0-rc1] kernel BUG at fs/btrfs/relocation.c:4285!

[liubo <liubo2009@cn.fujitsu.com>]

On 06/01/2011 04:12 PM, liubo wrote:
> On 06/01/2011 03:44 PM, liubo wrote:
>> > On 05/31/2011 08:27 AM, Tsutomu Itoh wrote:
>>>> >> > The panic occurred when 'btrfs fi bal /test5' was executed.
>>>> >> > 
>>>> >> > /test5 is as follows:
>>>> >> > # mount -o space_cache,compress=lzo /dev/sdc3 /test5
>>>> >> > #
>>>> >> > # btrfs fi sh /dev/sdc3
>>>> >> > Label: none  uuid: 38ec48b2-a64b-4225-8cc6-5eb08024dc64
>>>> >> >         Total devices 5 FS bytes used 7.87MB
>>>> >> >         devid    1 size 10.00GB used 2.02GB path /dev/sdc3
>>>> >> >         devid    2 size 15.01GB used 3.00GB path /dev/sdc5
>>>> >> >         devid    3 size 15.01GB used 3.00GB path /dev/sdc6
>>>> >> >         devid    4 size 20.01GB used 2.01GB path /dev/sdc7
>>>> >> >         devid    5 size 10.00GB used 2.01GB path /dev/sdc8
>>>> >> > 
>>>> >> > Btrfs v0.19-50-ge6bd18d
>>>> >> > # btrfs fi df /test5
>>>> >> > Data, RAID0: total=10.00GB, used=3.52MB
>>>> >> > Data: total=8.00MB, used=1.60MB
>>>> >> > System, RAID1: total=8.00MB, used=4.00KB
>>>> >> > System: total=4.00MB, used=0.00
>>>> >> > Metadata, RAID1: total=1.00GB, used=216.00KB
>>>> >> > Metadata: total=8.00MB, used=0.00
>>>> >> > 
>> > 
>> > Hi, Itoh san, 
>> > 
>> > I've come up with a patch aiming to fix this bug.
>> > The problems is that the inode allocator stores one inode cache per root,
>> > which is at least not good for relocation tree, cause we only find
>> > new inode number from fs tree or file tree (subvol/snapshot).
>> > 
>> > I've tested with your run.sh and it works well on my box, so you can try this:
>> > 

I've tested the following patch for about 1.5 hour, and nothing happened.
And would you please test this patch?

thanks,

From: Liu Bo <liubo2009@cn.fujitsu.com>

[PATCH] Btrfs: fix save ino cache bug

We just get new inode number from fs root or subvol/snap root,
so we'd like to save fs/subvol/snap root's inode cache into disk.

Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
---
 fs/btrfs/inode-map.c |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/fs/btrfs/inode-map.c b/fs/btrfs/inode-map.c
index 0009705..8c0c25b 100644
--- a/fs/btrfs/inode-map.c
+++ b/fs/btrfs/inode-map.c
@@ -372,6 +372,12 @@ int btrfs_save_ino_cache(struct btrfs_root *root,
 	int prealloc;
 	bool retry = false;
 
+	/* only fs tree and subvol/snap needs ino cache */
+	if (root->root_key.objectid != BTRFS_FS_TREE_OBJECTID &&
+	    (root->root_key.objectid < BTRFS_FIRST_FREE_OBJECTID ||
+	     root->root_key.objectid > BTRFS_LAST_FREE_OBJECTID))
+		return 0;
+
 	path = btrfs_alloc_path();
 	if (!path)
 		return -ENOMEM;
-- 
1.6.5.2