[PATCH] Turn off XBF_READ_AHEAD in io completion

[Lachlan McIlroy <lachlan@xxxxxxx>]

Read-ahead of an inode cluster will set XBF_READ_AHEAD in the buffer.
If we don't remove the flag it will still be set when we flush the
buffer back to disk.  Not sure if leaving this flag set causes any
serious problems but it does trigger an assert.

--- fs/xfs/linux-2.6/xfs_buf.c_1.247    2007-10-29 16:01:29.000000000 +1100
+++ fs/xfs/linux-2.6/xfs_buf.c  2007-10-29 14:00:53.000000000 +1100
@@ -1032,7 +1032,7 @@ xfs_buf_ioend(
        xfs_buf_t               *bp,
        int                     schedule)
 {
-       bp->b_flags &= ~(XBF_READ | XBF_WRITE);
+       bp->b_flags &= ~(XBF_READ | XBF_WRITE | XBF_READ_AHEAD);
        if (bp->b_error == 0)
                bp->b_flags |= XBF_DONE;