From 6d465e895343225e3ad35fe10d7b3e9f2f18faec Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@lst.de>
Date: Wed, 11 Jul 2018 22:26:03 -0700
Subject: [PATCH] xfs: move all writeback buffer_head manipulation into
 xfs_map_at_offset
Git-commit: 6d465e895343225e3ad35fe10d7b3e9f2f18faec
Patch-mainline: v4.19-rc1
References: bsc#1138014

This keeps it in a single place so it can be made otional more easily.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Anthony Iliopoulos <ailiopoulos@suse.com>

---
 fs/xfs/xfs_aops.c |   22 +++++-----------------
 1 file changed, 5 insertions(+), 17 deletions(-)

--- a/fs/xfs/xfs_aops.c
+++ b/fs/xfs/xfs_aops.c
@@ -507,21 +507,6 @@
 }
 
 STATIC void
-xfs_start_buffer_writeback(
-	struct buffer_head	*bh)
-{
-	ASSERT(buffer_mapped(bh));
-	ASSERT(buffer_locked(bh));
-	ASSERT(!buffer_delay(bh));
-	ASSERT(!buffer_unwritten(bh));
-
-	bh->b_end_io = NULL;
-	set_buffer_async_write(bh);
-	set_buffer_uptodate(bh);
-	clear_buffer_dirty(bh);
-}
-
-STATIC void
 xfs_start_page_writeback(
 	struct page		*page,
 	int			clear_dirty)
@@ -738,6 +723,7 @@
 	ASSERT(imap->br_startblock != HOLESTARTBLOCK);
 	ASSERT(imap->br_startblock != DELAYSTARTBLOCK);
 
+	lock_buffer(bh);
 	xfs_map_buffer(inode, bh, imap, offset);
 	set_buffer_mapped(bh);
 	clear_buffer_delay(bh);
@@ -750,6 +736,10 @@
 	 * set the bdev now.
 	 */
 	bh->b_bdev = xfs_find_bdev_for_inode(inode);
+	bh->b_end_io = NULL;
+	set_buffer_async_write(bh);
+	set_buffer_uptodate(bh);
+	clear_buffer_dirty(bh);
 }
 
 /*
@@ -940,11 +930,9 @@
 		if (wpc->io_type == XFS_IO_HOLE)
 			continue;
 
-		lock_buffer(bh);
 		xfs_map_at_offset(inode, bh, &wpc->imap, file_offset);
 		xfs_add_to_ioend(inode, file_offset, page, wpc, wbc,
 				&submit_list);
-		xfs_start_buffer_writeback(bh);
 		count++;
 	}