Merge tag 'xfs-for-linus-4.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs

Pull xfs fixes from Dave Chinner:
 "There are a couple of recently found, long standing remote attribute
  corruption fixes caused by log recovery getting confused after a
  crash, and the new DAX code in XFS (merged in 4.2-rc1) needs to
  actually use the DAX fault path on read faults.

  Summary:

   - remote attribute log recovery corruption fixes

   - DAX page faults need to use direct mappings, not a page cache
     mapping"

* tag 'xfs-for-linus-4.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs:
  xfs: remote attributes need to be considered data
  xfs: remote attribute headers contain an invalid LSN
  xfs: call dax_fault on read page faults for DAX

1 files changed, 8 insertions, 3 deletions

diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c
index 01dd228ca05e..480ebba8464f 100644
--- a/fs/xfs/xfs_log_recover.c
+++ b/fs/xfs/xfs_log_recover.c
@@ -1886,9 +1886,14 @@ xlog_recover_get_buf_lsn(
 		uuid = &((struct xfs_dir3_blk_hdr *)blk)->uuid;
 		break;
 	case XFS_ATTR3_RMT_MAGIC:
-		lsn = be64_to_cpu(((struct xfs_attr3_rmt_hdr *)blk)->rm_lsn);
-		uuid = &((struct xfs_attr3_rmt_hdr *)blk)->rm_uuid;
-		break;
+		/*
+		 * Remote attr blocks are written synchronously, rather than
+		 * being logged. That means they do not contain a valid LSN
+		 * (i.e. transactionally ordered) in them, and hence any time we
+		 * see a buffer to replay over the top of a remote attribute
+		 * block we should simply do so.
+		 */
+		goto recover_immediately;
 	case XFS_SB_MAGIC:
 		lsn = be64_to_cpu(((struct xfs_dsb *)blk)->sb_lsn);
 		uuid = &((struct xfs_dsb *)blk)->sb_uuid;