xfs: cleanup I/O-related buffer flags

Remove the unused and misnamed _XBF_RUN_QUEUES flag, rename XBF_LOG_BUFFER
to the more fitting XBF_SYNCIO, and split XBF_ORDERED into XBF_FUA and
XBF_FLUSH to allow more fine grained control over the bio flags.  Also
cleanup processing of the flags in _xfs_buf_ioapply to make more sense,
and renumber the sparse flag number space to group flags by purpose.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>

1 files changed, 15 insertions, 20 deletions

diff --git a/fs/xfs/linux-2.6/xfs_buf.c b/fs/xfs/linux-2.6/xfs_buf.c
index 6ad5ae249bfb..a0d97c5a3f15 100644
--- a/fs/xfs/linux-2.6/xfs_buf.c
+++ b/fs/xfs/linux-2.6/xfs_buf.c
@@ -592,10 +592,8 @@ _xfs_buf_read(
         ASSERT(!(flags & (XBF_DELWRI|XBF_WRITE)));
         ASSERT(bp->b_bn != XFS_BUF_DADDR_NULL);
 
-        bp->b_flags &= ~(XBF_WRITE | XBF_ASYNC | XBF_DELWRI | \
-                        XBF_READ_AHEAD | _XBF_RUN_QUEUES);
-        bp->b_flags |= flags & (XBF_READ | XBF_ASYNC | \
-                        XBF_READ_AHEAD | _XBF_RUN_QUEUES);
+        bp->b_flags &= ~(XBF_WRITE | XBF_ASYNC | XBF_DELWRI | XBF_READ_AHEAD);
+        bp->b_flags |= flags & (XBF_READ | XBF_ASYNC | XBF_READ_AHEAD);
 
         status = xfs_buf_iorequest(bp);
         if (status || XFS_BUF_ISERROR(bp) || (flags & XBF_ASYNC))
@@ -1211,23 +1209,21 @@ _xfs_buf_ioapply(
         total_nr_pages = bp->b_page_count;
         map_i = 0;
 
-        if (bp->b_flags & XBF_ORDERED) {
-                ASSERT(!(bp->b_flags & XBF_READ));
-                rw = WRITE_FLUSH_FUA;
-        } else if (bp->b_flags & XBF_LOG_BUFFER) {
-                ASSERT(!(bp->b_flags & XBF_READ_AHEAD));
-                bp->b_flags &= ~_XBF_RUN_QUEUES;
-                rw = (bp->b_flags & XBF_WRITE) ? WRITE_SYNC : READ_SYNC;
-        } else if (bp->b_flags & _XBF_RUN_QUEUES) {
-                ASSERT(!(bp->b_flags & XBF_READ_AHEAD));
-                bp->b_flags &= ~_XBF_RUN_QUEUES;
-                rw = (bp->b_flags & XBF_WRITE) ? WRITE_META : READ_META;
+        if (bp->b_flags & XBF_WRITE) {
+                if (bp->b_flags & XBF_SYNCIO)
+                        rw = WRITE_SYNC;
+                else
+                        rw = WRITE;
+                if (bp->b_flags & XBF_FUA)
+                        rw |= REQ_FUA;
+                if (bp->b_flags & XBF_FLUSH)
+                        rw |= REQ_FLUSH;
+        } else if (bp->b_flags & XBF_READ_AHEAD) {
+                rw = READA;
         } else {
-                rw = (bp->b_flags & XBF_WRITE) ? WRITE :
-                     (bp->b_flags & XBF_READ_AHEAD) ? READA : READ;
+                rw = READ;
         }
 
-
 next_chunk:
         atomic_inc(&bp->b_io_remaining);
         nr_pages = BIO_MAX_SECTORS >> (PAGE_SHIFT - BBSHIFT);
@@ -1689,8 +1685,7 @@ xfs_buf_delwri_split(
                                 break;
                         }
 
-                        bp->b_flags &= ~(XBF_DELWRI|_XBF_DELWRI_Q|
-                                         _XBF_RUN_QUEUES);
+                        bp->b_flags &= ~(XBF_DELWRI | _XBF_DELWRI_Q);
                         bp->b_flags |= XBF_WRITE;
                         list_move_tail(&bp->b_list, list);
                         trace_xfs_buf_delwri_split(bp, _RET_IP_);