[merged mm-stable] fsdax-dedupe-iter-two-files-at-the-same-time.patch removed from -mm tree

[merged mm-stable] fsdax-dedupe-iter-two-files-at-the-same-time.patch removed from -mm tree

[Andrew Morton]

The quilt patch titled
     Subject: fsdax: dedupe: iter two files at the same time
has been removed from the -mm tree.  Its filename was
     fsdax-dedupe-iter-two-files-at-the-same-time.patch

This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

------------------------------------------------------
From: Shiyang Ruan <ruansy.fnst@fujitsu.com>
Subject: fsdax: dedupe: iter two files at the same time
Date: Thu, 1 Dec 2022 15:31:41 +0000

The iomap_iter() on a range of one file may loop more than once.  In this
case, the inner dst_iter can update its iomap but the outer src_iter
can't.  This may cause the wrong remapping in filesystem.  Let them called
at the same time.

Link: https://lkml.kernel.org/r/1669908701-93-1-git-send-email-ruansy.fnst@fujitsu.com
Signed-off-by: Shiyang Ruan <ruansy.fnst@fujitsu.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 fs/dax.c |   16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

--- a/fs/dax.c~fsdax-dedupe-iter-two-files-at-the-same-time
+++ a/fs/dax.c
@@ -1965,15 +1965,15 @@ int dax_dedupe_file_range_compare(struct
 		.len		= len,
 		.flags		= IOMAP_DAX,
 	};
-	int ret;
+	int ret, compared = 0;
 
-	while ((ret = iomap_iter(&src_iter, ops)) > 0) {
-		while ((ret = iomap_iter(&dst_iter, ops)) > 0) {
-			dst_iter.processed = dax_range_compare_iter(&src_iter,
-						&dst_iter, len, same);
-		}
-		if (ret <= 0)
-			src_iter.processed = ret;
+	while ((ret = iomap_iter(&src_iter, ops)) > 0 &&
+	       (ret = iomap_iter(&dst_iter, ops)) > 0) {
+		compared = dax_range_compare_iter(&src_iter, &dst_iter, len,
+						  same);
+		if (compared < 0)
+			return ret;
+		src_iter.processed = dst_iter.processed = compared;
 	}
 	return ret;
 }
_

Patches currently in -mm which might be from ruansy.fnst@fujitsu.com are