| Message ID | 1403752096-4776-1-git-send-email-wangsl.fnst@cn.fujitsu.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
On Thu, Jun 26, 2014 at 11:08:16AM +0800, Wang Shilong wrote: > Balance recovery is called when RW mounting or remounting from > RO to RW, it is called to finish roots merging. > > When doing balance recovery, relocation root's corresponding > fs root(whose root refs is 0) might be destroyed by cleaner > thread, this will make btrfs fail to mount. > > Fix this problem by holding @cleaner_mutex when doing balance > recovery. > > Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com> I don't pretend to understand all the dark corners of relocation, but this looks as a correct fix to me. Relocation and cleaner are mutually exclusive in the normal case. Reviewed-by: David Sterba <dsterba@suse.cz> -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 8bb4aa1..61d8e87 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -2904,7 +2904,9 @@ retry_root_backup: if (ret) goto fail_qgroup; + mutex_lock(&fs_info->cleaner_mutex); ret = btrfs_recover_relocation(tree_root); + mutex_unlock(&fs_info->cleaner_mutex); if (ret < 0) { printk(KERN_WARNING "BTRFS: failed to recover relocation\n"); diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index 4662d92..b6ebde2 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -1467,7 +1467,9 @@ static int btrfs_remount(struct super_block *sb, int *flags, char *data) goto restore; /* recover relocation */ + mutex_lock(&fs_info->cleaner_mutex); ret = btrfs_recover_relocation(root); + mutex_unlock(&fs_info->cleaner_mutex); if (ret) goto restore;
Balance recovery is called when RW mounting or remounting from RO to RW, it is called to finish roots merging. When doing balance recovery, relocation root's corresponding fs root(whose root refs is 0) might be destroyed by cleaner thread, this will make btrfs fail to mount. Fix this problem by holding @cleaner_mutex when doing balance recovery. Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com> --- fs/btrfs/disk-io.c | 2 ++ fs/btrfs/super.c | 2 ++ 2 files changed, 4 insertions(+)