[PATCH 02/24] xfs: use iomap for blocksize == PAGE_SIZE readpage and readpages

[Christoph Hellwig <hch@lst.de>]

For file systems with a block size that equals the page size we never do
partial reads, so we can use the buffer_head-less iomap versions of
readpage and readpages without conflicting with the buffer_head structures
create later in write_begin.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_aops.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c
index ca6903726689..dba439ebfe4c 100644
--- a/fs/xfs/xfs_aops.c
+++ b/fs/xfs/xfs_aops.c
@@ -1402,6 +1402,8 @@ xfs_vm_readpage(
 	struct page		*page)
 {
 	trace_xfs_vm_readpage(page->mapping->host, 1);
+	if (i_blocksize(page->mapping->host) == PAGE_SIZE)
+		return iomap_readpage(page, &xfs_iomap_ops);
 	return mpage_readpage(page, xfs_get_blocks);
 }
 
@@ -1413,6 +1415,8 @@ xfs_vm_readpages(
 	unsigned		nr_pages)
 {
 	trace_xfs_vm_readpages(mapping->host, nr_pages);
+	if (i_blocksize(mapping->host) == PAGE_SIZE)
+		return iomap_readpages(mapping, pages, nr_pages, &xfs_iomap_ops);
 	return mpage_readpages(mapping, pages, nr_pages, xfs_get_blocks);
 }
 
-- 
2.17.1