With all in-tree filesystems implementing ->iomap_next(), drop the
->iomap_begin()/->iomap_end() path.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
---
 fs/iomap/direct-io.c  | 47 ++++++++++++++-----------------------------
 fs/iomap/iter.c       |  6 +-----
 include/linux/iomap.h |  6 ++----
 3 files changed, 18 insertions(+), 41 deletions(-)

diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c
index fcdae3ef6dd0..a47369e6b4e1 100644
--- a/fs/iomap/direct-io.c
+++ b/fs/iomap/direct-io.c
@@ -1001,18 +1001,13 @@ iomap_dio_simple_supported(struct kiocb *iocb, struct iov_iter *iter,
 }
 
 static inline void
-iomap_dio_simple_finish(struct iomap_iter *iomi, const struct iomap_ops *ops,
-		size_t len, size_t written)
+iomap_dio_simple_finish(struct iomap_iter *iomi, iomap_iter_next_fn next,
+		size_t written)
 {
-	if (ops->iomap_next) {
-		iomi->iter_start_pos = iomi->pos;
-		iomi->pos += written;
-		iomi->len -= written;
-		ops->iomap_next(iomi, &iomi->iomap, &iomi->srcmap);
-	} else if (ops->iomap_end) {
-		ops->iomap_end(iomi->inode, iomi->pos, len, written,
-			       iomi->flags, &iomi->iomap);
-	}
+	iomi->iter_start_pos = iomi->pos;
+	iomi->pos += written;
+	iomi->len -= written;
+	next(iomi, &iomi->iomap, &iomi->srcmap);
 }
 
 /*
@@ -1079,25 +1074,13 @@ iomap_dio_simple(struct kiocb *iocb, struct iov_iter *iter,
 
 	inode_dio_begin(inode);
 
-	if (ops->iomap_next) {
-		ret = ops->iomap_next(&iomi, &iomi.iomap, &iomi.srcmap);
-		if (ret <= 0) {
-			inode_dio_end(inode);
-			/*
-			 * the first iteration must yield a mapping (>0) or an
-			 * error
-			 */
-			if (WARN_ON_ONCE(!ret))
-				return -EFAULT;
-			return ret;
-		}
-	} else {
-		ret = ops->iomap_begin(inode, iomi.pos, count, iomi.flags,
-				       &iomi.iomap, &iomi.srcmap);
-		if (ret) {
-			inode_dio_end(inode);
-			return ret;
-		}
+	ret = ops->iomap_next(&iomi, &iomi.iomap, &iomi.srcmap);
+	if (ret <= 0) {
+		inode_dio_end(inode);
+		/* the first iteration must yield a mapping (>0) or an error */
+		if (WARN_ON_ONCE(!ret))
+			return -EFAULT;
+		return ret;
 	}
 
 	if (iomi.iomap.type != IOMAP_MAPPED ||
@@ -1163,7 +1146,7 @@ iomap_dio_simple(struct kiocb *iocb, struct iov_iter *iter,
 	 * iomap_next() call on the hot read path.
 	 */
 	if (!(dio_flags & IOMAP_DIO_NO_IOMAP_END))
-		iomap_dio_simple_finish(&iomi, ops, count, count);
+		iomap_dio_simple_finish(&iomi, ops->iomap_next, count);
 
 	if (!wait_for_completion) {
 		bio->bi_end_io = iomap_dio_simple_end_io;
@@ -1181,7 +1164,7 @@ iomap_dio_simple(struct kiocb *iocb, struct iov_iter *iter,
 	bio_put(bio);
 out_iomap_end:
 	if (!(dio_flags & IOMAP_DIO_NO_IOMAP_END))
-		iomap_dio_simple_finish(&iomi, ops, count, 0);
+		iomap_dio_simple_finish(&iomi, ops->iomap_next, 0);
 	inode_dio_end(inode);
 	return ret;
 }
diff --git a/fs/iomap/iter.c b/fs/iomap/iter.c
index e05574602946..f7c4d5cf56be 100644
--- a/fs/iomap/iter.c
+++ b/fs/iomap/iter.c
@@ -107,11 +107,7 @@ int iomap_iter(struct iomap_iter *iter, const struct iomap_ops *ops)
 
 	trace_iomap_iter(iter, ops, _RET_IP_);
 
-	if (ops->iomap_next)
-		ret = ops->iomap_next(iter, &iter->iomap, &iter->srcmap);
-	else
-		ret = iomap_iter_next(iter, &iter->iomap, &iter->srcmap,
-				ops->iomap_begin, ops->iomap_end);
+	ret = ops->iomap_next(iter, &iter->iomap, &iter->srcmap);
 
 	iter->status = 0;
 	if (ret > 0)
diff --git a/include/linux/iomap.h b/include/linux/iomap.h
index 8662bd528e9e..66e2f7186299 100644
--- a/include/linux/iomap.h
+++ b/include/linux/iomap.h
@@ -194,7 +194,7 @@ struct iomap_write_ops {
 };
 
 /*
- * Flags for iomap_begin / iomap_end.  No flag implies a read.
+ * Flags for iomap_next.  No flag implies a read.
  */
 #define IOMAP_WRITE		(1 << 0) /* writing, must allocate blocks */
 #define IOMAP_ZERO		(1 << 1) /* zeroing operation, may skip holes */
@@ -239,8 +239,6 @@ typedef int (*iomap_iter_next_fn)(const struct iomap_iter *iter,
 		struct iomap *iomap, struct iomap *srcmap);
 
 struct iomap_ops {
-	iomap_iter_begin_fn iomap_begin;
-	iomap_iter_end_fn iomap_end;
 	iomap_iter_next_fn iomap_next;
 };
 
@@ -255,7 +253,7 @@ struct iomap_ops {
  *	incremental iter advance.
  * @status: Status of the most recent iteration. Zero on success or a negative
  *	errno on error.
- * @flags: Zero or more of the iomap_begin flags above.
+ * @flags: Zero or more of the iomap_next flags above.
  * @iomap: Map describing the I/O iteration
  * @srcmap: Source map for COW operations
  */
-- 
2.52.0