1 files changed, 47 insertions, 44 deletions

diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
index c558ac15bc87..650a67b7d223 100644
--- a/fs/iomap/buffered-io.c
+++ b/fs/iomap/buffered-io.c
@@ -1571,7 +1571,7 @@ u32 iomap_finish_ioend_buffered(struct iomap_ioend *ioend)
 	return folio_count;
 }
 
-static void iomap_writepage_end_bio(struct bio *bio)
+static void ioend_writeback_end_bio(struct bio *bio)
 {
 	struct iomap_ioend *ioend = iomap_ioend_from_bio(bio);
 
@@ -1580,42 +1580,30 @@ static void iomap_writepage_end_bio(struct bio *bio)
 }
 
 /*
- * Submit an ioend.
- *
- * If @error is non-zero, it means that we have a situation where some part of
- * the submission process has failed after we've marked pages for writeback.
- * We cannot cancel ioend directly in that case, so call the bio end I/O handler
- * with the error status here to run the normal I/O completion handler to clear
- * the writeback bit and let the file system proess the errors.
+ * We cannot cancel the ioend directly in case of an error, so call the bio end
+ * I/O handler with the error status here to run the normal I/O completion
+ * handler.
  */
-static int iomap_submit_ioend(struct iomap_writepage_ctx *wpc, int error)
+int iomap_ioend_writeback_submit(struct iomap_writepage_ctx *wpc, int error)
 {
-	if (!wpc->ioend)
-		return error;
+	struct iomap_ioend *ioend = wpc->wb_ctx;
 
-	/*
-	 * Let the file systems prepare the I/O submission and hook in an I/O
-	 * comletion handler.  This also needs to happen in case after a
-	 * failure happened so that the file system end I/O handler gets called
-	 * to clean up.
-	 */
-	if (wpc->ops->submit_ioend) {
-		error = wpc->ops->submit_ioend(wpc, error);
-	} else {
-		if (WARN_ON_ONCE(wpc->iomap.flags & IOMAP_F_ANON_WRITE))
-			error = -EIO;
-		if (!error)
-			submit_bio(&wpc->ioend->io_bio);
-	}
+	if (!ioend->io_bio.bi_end_io)
+		ioend->io_bio.bi_end_io = ioend_writeback_end_bio;
+
+	if (WARN_ON_ONCE(wpc->iomap.flags & IOMAP_F_ANON_WRITE))
+		error = -EIO;
 
 	if (error) {
-		wpc->ioend->io_bio.bi_status = errno_to_blk_status(error);
-		bio_endio(&wpc->ioend->io_bio);
+		ioend->io_bio.bi_status = errno_to_blk_status(error);
+		bio_endio(&ioend->io_bio);
+		return error;
 	}
 
-	wpc->ioend = NULL;
-	return error;
+	submit_bio(&ioend->io_bio);
+	return 0;
 }
+EXPORT_SYMBOL_GPL(iomap_ioend_writeback_submit);
 
 static struct iomap_ioend *iomap_alloc_ioend(struct iomap_writepage_ctx *wpc,
 		loff_t pos, u16 ioend_flags)
@@ -1626,7 +1614,6 @@ static struct iomap_ioend *iomap_alloc_ioend(struct iomap_writepage_ctx *wpc,
 			       REQ_OP_WRITE | wbc_to_write_flags(wpc->wbc),
 			       GFP_NOFS, &iomap_ioend_bioset);
 	bio->bi_iter.bi_sector = iomap_sector(&wpc->iomap, pos);
-	bio->bi_end_io = iomap_writepage_end_bio;
 	bio->bi_write_hint = wpc->inode->i_write_hint;
 	wbc_init_bio(wpc->wbc, bio);
 	wpc->nr_folios = 0;
@@ -1636,16 +1623,17 @@ static struct iomap_ioend *iomap_alloc_ioend(struct iomap_writepage_ctx *wpc,
 static bool iomap_can_add_to_ioend(struct iomap_writepage_ctx *wpc, loff_t pos,
 		u16 ioend_flags)
 {
+	struct iomap_ioend *ioend = wpc->wb_ctx;
+
 	if (ioend_flags & IOMAP_IOEND_BOUNDARY)
 		return false;
 	if ((ioend_flags & IOMAP_IOEND_NOMERGE_FLAGS) !=
-	    (wpc->ioend->io_flags & IOMAP_IOEND_NOMERGE_FLAGS))
+	    (ioend->io_flags & IOMAP_IOEND_NOMERGE_FLAGS))
 		return false;
-	if (pos != wpc->ioend->io_offset + wpc->ioend->io_size)
+	if (pos != ioend->io_offset + ioend->io_size)
 		return false;
 	if (!(wpc->iomap.flags & IOMAP_F_ANON_WRITE) &&
-	    iomap_sector(&wpc->iomap, pos) !=
-	    bio_end_sector(&wpc->ioend->io_bio))
+	    iomap_sector(&wpc->iomap, pos) != bio_end_sector(&ioend->io_bio))
 		return false;
 	/*
 	 * Limit ioend bio chain lengths to minimise IO completion latency. This
@@ -1671,6 +1659,7 @@ static bool iomap_can_add_to_ioend(struct iomap_writepage_ctx *wpc, loff_t pos,
 ssize_t iomap_add_to_ioend(struct iomap_writepage_ctx *wpc, struct folio *folio,
 		loff_t pos, loff_t end_pos, unsigned int dirty_len)
 {
+	struct iomap_ioend *ioend = wpc->wb_ctx;
 	struct iomap_folio_state *ifs = folio->private;
 	size_t poff = offset_in_folio(folio, pos);
 	unsigned int ioend_flags = 0;
@@ -1701,15 +1690,17 @@ ssize_t iomap_add_to_ioend(struct iomap_writepage_ctx *wpc, struct folio *folio,
 	if (pos == wpc->iomap.offset && (wpc->iomap.flags & IOMAP_F_BOUNDARY))
 		ioend_flags |= IOMAP_IOEND_BOUNDARY;
 
-	if (!wpc->ioend || !iomap_can_add_to_ioend(wpc, pos, ioend_flags)) {
+	if (!ioend || !iomap_can_add_to_ioend(wpc, pos, ioend_flags)) {
 new_ioend:
-		error = iomap_submit_ioend(wpc, 0);
-		if (error)
-			return error;
-		wpc->ioend = iomap_alloc_ioend(wpc, pos, ioend_flags);
+		if (ioend) {
+			error = wpc->ops->writeback_submit(wpc, 0);
+			if (error)
+				return error;
+		}
+		wpc->wb_ctx = ioend = iomap_alloc_ioend(wpc, pos, ioend_flags);
 	}
 
-	if (!bio_add_folio(&wpc->ioend->io_bio, folio, map_len, poff))
+	if (!bio_add_folio(&ioend->io_bio, folio, map_len, poff))
 		goto new_ioend;
 
 	if (ifs)
@@ -1756,9 +1747,9 @@ new_ioend:
 	 * Note that this defeats the ability to chain the ioends of
 	 * appending writes.
 	 */
-	wpc->ioend->io_size += map_len;
-	if (wpc->ioend->io_offset + wpc->ioend->io_size > end_pos)
-		wpc->ioend->io_size = end_pos - wpc->ioend->io_offset;
+	ioend->io_size += map_len;
+	if (ioend->io_offset + ioend->io_size > end_pos)
+		ioend->io_size = end_pos - ioend->io_offset;
 
 	wbc_account_cgroup_owner(wpc->wbc, folio, map_len);
 	return map_len;
@@ -1953,6 +1944,18 @@ iomap_writepages(struct iomap_writepage_ctx *wpc)
 
 	while ((folio = writeback_iter(mapping, wpc->wbc, folio, &error)))
 		error = iomap_writepage_map(wpc, folio);
-	return iomap_submit_ioend(wpc, error);
+
+	/*
+	 * If @error is non-zero, it means that we have a situation where some
+	 * part of the submission process has failed after we've marked pages
+	 * for writeback.
+	 *
+	 * We cannot cancel the writeback directly in that case, so always call
+	 * ->writeback_submit to run the I/O completion handler to clear the
+	 * writeback bit and let the file system proess the errors.
+	 */
+	if (wpc->wb_ctx)
+		return wpc->ops->writeback_submit(wpc, error);
+	return error;
 }
 EXPORT_SYMBOL_GPL(iomap_writepages);