kill xfs_buf_iostart

xfs_buf_iostart is a "shared" helper for xfs_buf_read_flags,
xfs_bawrite, and xfs_bdwrite - except that there isn't much shared
code but rather special cases for each caller.

So remove this function and move the functionality to the caller.
xfs_bawrite and xfs_bdwrite are now big enough to be moved out of
line and the xfs_buf_read_flags is moved into a new helper called
_xfs_buf_read.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Niv Sardi <xaiki@sgi.com>

1 files changed, 48 insertions, 36 deletions

diff --git a/fs/xfs/linux-2.6/xfs_buf.c b/fs/xfs/linux-2.6/xfs_buf.c
index 36d5fcd3f593..cd89c56715a5 100644
--- a/fs/xfs/linux-2.6/xfs_buf.c
+++ b/fs/xfs/linux-2.6/xfs_buf.c
@@ -630,6 +630,29 @@ xfs_buf_get_flags(
 	return NULL;
 }
 
+STATIC int
+_xfs_buf_read(
+	xfs_buf_t		*bp,
+	xfs_buf_flags_t		flags)
+{
+	int			status;
+
+	XB_TRACE(bp, "_xfs_buf_read", (unsigned long)flags);
+
+	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);
+
+	status = xfs_buf_iorequest(bp);
+	if (!status && !(flags & XBF_ASYNC))
+		status = xfs_buf_iowait(bp);
+	return status;
+}
+
 xfs_buf_t *
 xfs_buf_read_flags(
 	xfs_buftarg_t		*target,
@@ -646,7 +669,7 @@ xfs_buf_read_flags(
 		if (!XFS_BUF_ISDONE(bp)) {
 			XB_TRACE(bp, "read", (unsigned long)flags);
 			XFS_STATS_INC(xb_get_read);
-			xfs_buf_iostart(bp, flags);
+			_xfs_buf_read(bp, flags);
 		} else if (flags & XBF_ASYNC) {
 			XB_TRACE(bp, "read_async", (unsigned long)flags);
 			/*
@@ -1048,50 +1071,39 @@ xfs_buf_ioerror(
 	XB_TRACE(bp, "ioerror", (unsigned long)error);
 }
 
-/*
- *	Initiate I/O on a buffer, based on the flags supplied.
- *	The b_iodone routine in the buffer supplied will only be called
- *	when all of the subsidiary I/O requests, if any, have been completed.
- */
 int
-xfs_buf_iostart(
-	xfs_buf_t		*bp,
-	xfs_buf_flags_t		flags)
+xfs_bawrite(
+	void			*mp,
+	struct xfs_buf		*bp)
 {
-	int			status = 0;
+	XB_TRACE(bp, "bawrite", 0);
 
-	XB_TRACE(bp, "iostart", (unsigned long)flags);
+	ASSERT(bp->b_bn != XFS_BUF_DADDR_NULL);
 
-	if (flags & XBF_DELWRI) {
-		bp->b_flags &= ~(XBF_READ | XBF_WRITE | XBF_ASYNC);
-		bp->b_flags |= flags & (XBF_DELWRI | XBF_ASYNC);
-		xfs_buf_delwri_queue(bp, 1);
-		return 0;
-	}
+	xfs_buf_delwri_dequeue(bp);
 
-	bp->b_flags &= ~(XBF_READ | XBF_WRITE | XBF_ASYNC | XBF_DELWRI | \
-			XBF_READ_AHEAD | _XBF_RUN_QUEUES);
-	bp->b_flags |= flags & (XBF_READ | XBF_WRITE | XBF_ASYNC | \
-			XBF_READ_AHEAD | _XBF_RUN_QUEUES);
+	bp->b_flags &= ~(XBF_READ | XBF_DELWRI | XBF_READ_AHEAD);
+	bp->b_flags |= (XBF_WRITE | XBF_ASYNC | _XBF_RUN_QUEUES);
+
+	bp->b_fspriv3 = mp;
+	bp->b_strat = xfs_bdstrat_cb;
+	return xfs_bdstrat_cb(bp);
+}
 
-	BUG_ON(bp->b_bn == XFS_BUF_DADDR_NULL);
+void
+xfs_bdwrite(
+	void			*mp,
+	struct xfs_buf		*bp)
+{
+	XB_TRACE(bp, "bdwrite", 0);
 
-	/* For writes allow an alternate strategy routine to precede
-	 * the actual I/O request (which may not be issued at all in
-	 * a shutdown situation, for example).
-	 */
-	status = (flags & XBF_WRITE) ?
-		xfs_buf_iostrategy(bp) : xfs_buf_iorequest(bp);
+	bp->b_strat = xfs_bdstrat_cb;
+	bp->b_fspriv3 = mp;
 
-	/* Wait for I/O if we are not an async request.
-	 * Note: async I/O request completion will release the buffer,
-	 * and that can already be done by this point.  So using the
-	 * buffer pointer from here on, after async I/O, is invalid.
-	 */
-	if (!status && !(flags & XBF_ASYNC))
-		status = xfs_buf_iowait(bp);
+	bp->b_flags &= ~XBF_READ;
+	bp->b_flags |= (XBF_DELWRI | XBF_ASYNC);
 
-	return status;
+	xfs_buf_delwri_queue(bp, 1);
 }
 
 STATIC_INLINE void