From: Darrick J. Wong <djwong@kernel.org>
Date: Thu, 20 Feb 2025 21:46:57 +0000 (-0800)
Subject: dio_writeback_race: align the directio buffer to base page size
X-Git-Tag: v2025.03.09~73
X-Git-Url: http://git.apps.os.sepia.ceph.com/?a=commitdiff_plain;h=23b67c61d21310e70fba210050bc002e6c7cbd6d;p=xfstests-dev.git

dio_writeback_race: align the directio buffer to base page size

There's no need to align the memory buffer for the direcio write to the
file allocation unit size; base page size will do.  This fixes the
following error when generic/761 is run against an XFS rt filesystem
with a 28k rtextsize:

 QA output created by 761
+failed to allocate aligned memory
+cat: /opt/foobar: No such file or directory
 Silence is golden

Cc: <fstests@vger.kernel.org> # v2025.02.16
Fixes: 17fb49493426ad ("fstests: add a generic test to verify direct IO writes with buffer contents change")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Zorro Lang <zlang@kernel.org>
---

diff --git a/src/dio-writeback-race.c b/src/dio-writeback-race.c
index 2d3156e5..cca7d0e3 100644
--- a/src/dio-writeback-race.c
+++ b/src/dio-writeback-race.c
@@ -102,7 +102,7 @@ int main (int argc, char *argv[])
 		fprintf(stderr, "missing argument\n");
 		goto error;
 	}
-	ret = posix_memalign(&buf, blocksize, blocksize);
+	ret = posix_memalign(&buf, sysconf(_SC_PAGESIZE), blocksize);
 	if (!buf) {
 		fprintf(stderr, "failed to allocate aligned memory\n");
 		exit(EXIT_FAILURE);