[Cluster-devel] [PATCH v2 2/2] iomap: Permit pages without an iop to enter writeback

[Andreas Gruenbacher]

Create an iop in the writeback path if one doesn't exist.  This allows
us to avoid creating the iop in some cases.  The only current case we
do that for is pages with inline data, but it can be extended to pages
which are entirely within an extent.  It also allows for an iop to be
removed from pages in the future (eg page split).

Co-developed-by: Matthew Wilcox (Oracle) <willy at infradead.org>
Signed-off-by: Matthew Wilcox (Oracle) <willy at infradead.org>
Signed-off-by: Andreas Gruenbacher <agruenba at redhat.com>
---
 fs/iomap/buffered-io.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
index 03537ecb2a94..6330dabc451e 100644
--- a/fs/iomap/buffered-io.c
+++ b/fs/iomap/buffered-io.c
@@ -1336,14 +1336,13 @@ iomap_writepage_map(struct iomap_writepage_ctx *wpc,
 		struct writeback_control *wbc, struct inode *inode,
 		struct page *page, u64 end_offset)
 {
-	struct iomap_page *iop = to_iomap_page(page);
+	struct iomap_page *iop = iomap_page_create(inode, page);
 	struct iomap_ioend *ioend, *next;
 	unsigned len = i_blocksize(inode);
 	u64 file_offset; /* file offset of page */
 	int error = 0, count = 0, i;
 	LIST_HEAD(submit_list);
 
-	WARN_ON_ONCE(i_blocks_per_page(inode, page) > 1 && !iop);
 	WARN_ON_ONCE(iop && atomic_read(&iop->write_bytes_pending) != 0);
 
 	/*
-- 
2.26.3