[RFC PATCH 02/10] iomap: Remove iomap_writepage_ctx from iomap_can_add_to_ioend()

["Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>]

In preparation for using this function without an iomap_writepage_ctx,
pass in the iomap and ioend.  Also simplify iomap_add_to_ioend() by
using the iomap & ioend directly.

Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
---
 fs/iomap/buffered-io.c | 35 ++++++++++++++++++-----------------
 1 file changed, 18 insertions(+), 17 deletions(-)

diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
index 03c7c97bc871..c91259530ac1 100644
--- a/fs/iomap/buffered-io.c
+++ b/fs/iomap/buffered-io.c
@@ -1273,25 +1273,24 @@ iomap_chain_bio(struct bio *prev)
 	return new;
 }
 
-static bool
-iomap_can_add_to_ioend(struct iomap_writepage_ctx *wpc, loff_t offset,
-		sector_t sector)
+static bool iomap_can_add_to_ioend(struct iomap *iomap,
+		struct iomap_ioend *ioend, loff_t offset, sector_t sector)
 {
-	if ((wpc->iomap.flags & IOMAP_F_SHARED) !=
-	    (wpc->ioend->io_flags & IOMAP_F_SHARED))
+	if ((iomap->flags & IOMAP_F_SHARED) !=
+	    (ioend->io_flags & IOMAP_F_SHARED))
 		return false;
-	if (wpc->iomap.type != wpc->ioend->io_type)
+	if (iomap->type != ioend->io_type)
 		return false;
-	if (offset != wpc->ioend->io_offset + wpc->ioend->io_size)
+	if (offset != ioend->io_offset + ioend->io_size)
 		return false;
-	if (sector != bio_end_sector(wpc->ioend->io_bio))
+	if (sector != bio_end_sector(ioend->io_bio))
 		return false;
 	/*
 	 * Limit ioend bio chain lengths to minimise IO completion latency. This
 	 * also prevents long tight loops ending page writeback on all the
 	 * folios in the ioend.
 	 */
-	if (wpc->ioend->io_folios >= IOEND_BATCH_SIZE)
+	if (ioend->io_folios >= IOEND_BATCH_SIZE)
 		return false;
 	return true;
 }
@@ -1306,24 +1305,26 @@ iomap_add_to_ioend(struct inode *inode, loff_t pos, struct folio *folio,
 		struct writeback_control *wbc, struct list_head *iolist)
 {
 	struct iomap *iomap = &wpc->iomap;
+	struct iomap_ioend *ioend = wpc->ioend;
 	sector_t sector = iomap_sector(iomap, pos);
 	unsigned len = i_blocksize(inode);
 	size_t poff = offset_in_folio(folio, pos);
 
-	if (!wpc->ioend || !iomap_can_add_to_ioend(wpc, pos, sector)) {
-		if (wpc->ioend)
-			list_add(&wpc->ioend->io_list, iolist);
-		wpc->ioend = iomap_alloc_ioend(inode, iomap, pos, sector, wbc);
+	if (!ioend || !iomap_can_add_to_ioend(iomap, ioend, pos, sector)) {
+		if (ioend)
+			list_add(&ioend->io_list, iolist);
+		ioend = iomap_alloc_ioend(inode, iomap, pos, sector, wbc);
+		wpc->ioend = ioend;
 	}
 
-	if (!bio_add_folio(wpc->ioend->io_bio, folio, len, poff)) {
-		wpc->ioend->io_bio = iomap_chain_bio(wpc->ioend->io_bio);
-		bio_add_folio(wpc->ioend->io_bio, folio, len, poff);
+	if (!bio_add_folio(ioend->io_bio, folio, len, poff)) {
+		ioend->io_bio = iomap_chain_bio(ioend->io_bio);
+		bio_add_folio(ioend->io_bio, folio, len, poff);
 	}
 
 	if (iop)
 		atomic_add(len, &iop->write_bytes_pending);
-	wpc->ioend->io_size += len;
+	ioend->io_size += len;
 	wbc_account_cgroup_owner(wbc, &folio->page, len);
 }
 
-- 
2.34.1