xfs: xfs_bioerror can die.

Internal buffer write error handling is a mess due to the unnatural
split between xfs_bioerror and xfs_bioerror_relse().

xfs_bwrite() only does sync IO and determines the handler to
call based on b_iodone, so for this caller the only difference
between xfs_bioerror() and xfs_bioerror_release() is the XBF_DONE
flag. We don't care what the XBF_DONE flag state is because we stale
the buffer in both paths - the next buffer lookup will clear
XBF_DONE because XBF_STALE is set. Hence we can use common
error handling for xfs_bwrite().

__xfs_buf_delwri_submit() is a similar - it's only ever called
on writes - all sync or async - and again there's no reason to
handle them any differently at all.

Clean up the nasty error handling and remove xfs_bioerror().

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>

1 files changed, 12 insertions, 46 deletions

diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c
index 0eee0f1f099e..409a8a06642a 100644
--- a/fs/xfs/xfs_buf.c
+++ b/fs/xfs/xfs_buf.c
@@ -1075,39 +1075,6 @@ xfs_buf_ioerror_alert(
 }
 
 /*
- * Called when we want to stop a buffer from getting written or read.
- * We attach the EIO error, muck with its flags, and call xfs_buf_ioend
- * so that the proper iodone callbacks get called.
- */
-STATIC int
-xfs_bioerror(
-        xfs_buf_t *bp)
-{
-#ifdef XFSERRORDEBUG
-        ASSERT(XFS_BUF_ISREAD(bp) || bp->b_iodone);
-#endif
-
-        /*
-         * No need to wait until the buffer is unpinned, we aren't flushing it.
-         */
-        xfs_buf_ioerror(bp, -EIO);
-
-        /*
-         * We're calling xfs_buf_ioend, so delete XBF_DONE flag. For
-         * sync IO, xfs_buf_ioend is going to remove a ref here.
-         */
-        if (!(bp->b_flags & XBF_ASYNC))
-                xfs_buf_hold(bp);
-        XFS_BUF_UNREAD(bp);
-        XFS_BUF_UNDONE(bp);
-        xfs_buf_stale(bp);
-
-        xfs_buf_ioend(bp);
-
-        return -EIO;
-}
-
-/*
  * Same as xfs_bioerror, except that we are releasing the buffer
  * here ourselves, and avoiding the xfs_buf_ioend call.
  * This is meant for userdata errors; metadata bufs come with
@@ -1155,19 +1122,19 @@ xfs_bwrite(
         ASSERT(xfs_buf_islocked(bp));
 
         bp->b_flags |= XBF_WRITE;
-        bp->b_flags &= ~(XBF_ASYNC | XBF_READ | _XBF_DELWRI_Q | XBF_WRITE_FAIL);
+        bp->b_flags &= ~(XBF_ASYNC | XBF_READ | _XBF_DELWRI_Q |
+                         XBF_WRITE_FAIL | XBF_DONE);
 
         if (XFS_FORCED_SHUTDOWN(bp->b_target->bt_mount)) {
                 trace_xfs_bdstrat_shut(bp, _RET_IP_);
 
-                /*
-                 * Metadata write that didn't get logged but written anyway.
-                 * These aren't associated with a transaction, and can be
-                 * ignored.
-                 */
-                if (!bp->b_iodone)
-                        return xfs_bioerror_relse(bp);
-                return xfs_bioerror(bp);
+                xfs_buf_ioerror(bp, -EIO);
+                xfs_buf_stale(bp);
+
+                /* sync IO, xfs_buf_ioend is going to remove a ref here */
+                xfs_buf_hold(bp);
+                xfs_buf_ioend(bp);
+                return -EIO;
         }
 
         xfs_buf_iorequest(bp);
@@ -1857,10 +1824,9 @@ __xfs_buf_delwri_submit(
                 if (XFS_FORCED_SHUTDOWN(bp->b_target->bt_mount)) {
                         trace_xfs_bdstrat_shut(bp, _RET_IP_);
 
-                        if (!bp->b_iodone)
-                                xfs_bioerror_relse(bp);
-                        else
-                                xfs_bioerror(bp);
+                        xfs_buf_ioerror(bp, -EIO);
+                        xfs_buf_stale(bp);
+                        xfs_buf_ioend(bp);
                         continue;
                 }
                 xfs_buf_iorequest(bp);