The patch titled
Subject: fsdax: dedupe should compare the min of two iters' length
has been added to the -mm mm-unstable branch. Its filename is
fsdax-dedupe-should-compare-the-min-of-two-iters-length.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/fsdax-dedupe-should-compare-the-min-of-two-iters-length.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days
------------------------------------------------------
From: Shiyang Ruan <ruansy.fnst@xxxxxxxxxxx>
Subject: fsdax: dedupe should compare the min of two iters' length
Date: Wed, 22 Mar 2023 07:25:58 +0000
In an dedupe comparison iter loop, the length of iomap_iter decreases
because it implies the remaining length after each iteration. The compare
function should use the min length of the current iters, not the total
length.
Link: https://lkml.kernel.org/r/1679469958-2-1-git-send-email-ruansy.fnst@xxxxxxxxxxx
Fixes: 0e79e3736d54 ("fsdax: dedupe: iter two files at the same time")
Signed-off-by: Shiyang Ruan <ruansy.fnst@xxxxxxxxxxx>
Reviewed-by: Darrick J. Wong <djwong@xxxxxxxxxx>
Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
Cc: Jan Kara <jack@xxxxxxx>
Cc: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
--- a/fs/dax.c~fsdax-dedupe-should-compare-the-min-of-two-iters-length
+++ a/fs/dax.c
@@ -2027,8 +2027,8 @@ int dax_dedupe_file_range_compare(struct
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);
+ compared = dax_range_compare_iter(&src_iter, &dst_iter,
+ min(src_iter.len, dst_iter.len), same);
if (compared < 0)
return ret;
src_iter.processed = dst_iter.processed = compared;
_
Patches currently in -mm which might be from ruansy.fnst@xxxxxxxxxxx are
fsdax-unshare-zero-destination-if-srcmap-is-hole-or-unwritten.patch
fsdax-dedupe-should-compare-the-min-of-two-iters-length.patch
