From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E805C1891AB for ; Sun, 9 Nov 2025 23:20:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762730460; cv=none; b=VkMN1QCV15vzxk6uUKz+fL/lHPGEsAOAio3HKJUDG6r+h7X2Rxt3h70gOEdpLoT7tpcVw6/fI92OcvZUDqLC0RKXOkVtXjXtv7diq825z4MtxkKNMD5+fFXhU9hdsCcqJRXn3LQujCSps/HM69yv/93NIGvHZC7p14XQt1NMB2o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762730460; c=relaxed/simple; bh=CQL/x4zGmt9d0GT2HzyviMhaUZRIHMHrlam0dNlnPXM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=u+f7yT+fdUB10/bNMKjGrU0nyKAjMhQA/hauf4M3pQoXGOl8IEmIg64OBanIxk49Tk3fthgFFlLivv/9wbHBHvhDnovPQUeIT1/MM5qwpmmrCTlzadBvQ/Uk95WR/PcMG2kO6kPIKMuci7+WyDYVTclqoRZGV47la/ng3LLQLss= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=rbvhfb+B; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="rbvhfb+B" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B791DC4CEF7; Sun, 9 Nov 2025 23:20:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1762730459; bh=CQL/x4zGmt9d0GT2HzyviMhaUZRIHMHrlam0dNlnPXM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rbvhfb+B0dJeVNgmYb44oW07ksmJdrr5HxaC5ywCe0TuIdWW5srMfHSX1awMhubsF M1+5fuBoQNOAihJHww/9xi95crcqU5Yyxx1nqalvAa1IR/o2KuOK0Pys1WKHGd+T8l 7HZhCb7HssTWTeAIUTI7YZPT99CPHqfKjrDl7d/bCdgXWcGWEcmHxHVNucqOUc76hf F+hYdKMpnevUPoIfFrMWiShulobunShqPZSrUA+1VV+x4ZO3YyNqEdYpy6zpcbPoD5 +InihPWV2mBE1RnkX8+mgq3q3Wba28ZBjOCNG8Q41Uy00Erx6/d8c5lEcuFID5NzQK AmuK5DacN5UDQ== From: Sasha Levin To: stable@vger.kernel.org Cc: "Darrick J. Wong" , John Garry , Carlos Maiolino , Sasha Levin Subject: [PATCH 6.17.y 1/2] xfs: fix delalloc write failures in software-provided atomic writes Date: Sun, 9 Nov 2025 18:20:56 -0500 Message-ID: <20251109232057.531285-1-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <2025110942-language-suspect-13bc@gregkh> References: <2025110942-language-suspect-13bc@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: "Darrick J. Wong" [ Upstream commit 8d54eacd82a0623a963e0c150ad3b02970638b0d ] With the 20 Oct 2025 release of fstests, generic/521 fails for me on regular (aka non-block-atomic-writes) storage: QA output created by 521 dowrite: write: Input/output error LOG DUMP (8553 total operations): 1( 1 mod 256): SKIPPED (no operation) 2( 2 mod 256): WRITE 0x7e000 thru 0x8dfff (0x10000 bytes) HOLE 3( 3 mod 256): READ 0x69000 thru 0x79fff (0x11000 bytes) 4( 4 mod 256): FALLOC 0x53c38 thru 0x5e853 (0xac1b bytes) INTERIOR 5( 5 mod 256): COPY 0x55000 thru 0x59fff (0x5000 bytes) to 0x25000 thru 0x29fff 6( 6 mod 256): WRITE 0x74000 thru 0x88fff (0x15000 bytes) 7( 7 mod 256): ZERO 0xedb1 thru 0x11693 (0x28e3 bytes) with a warning in dmesg from iomap about XFS trying to give it a delalloc mapping for a directio write. Fix the software atomic write iomap_begin code to convert the reservation into a written mapping. This doesn't fix the data corruption problems reported by generic/760, but it's a start. Cc: stable@vger.kernel.org # v6.16 Fixes: bd1d2c21d5d249 ("xfs: add xfs_atomic_write_cow_iomap_begin()") Signed-off-by: Darrick J. Wong Reviewed-by: John Garry Signed-off-by: Carlos Maiolino Stable-dep-of: 8d7bba1e8314 ("xfs: fix various problems in xfs_atomic_write_cow_iomap_begin") Signed-off-by: Sasha Levin --- fs/xfs/xfs_iomap.c | 21 +++++++++++++++++++-- 1 file changed, 19 insertions(+), 2 deletions(-) diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c index 2a74f29573410..a4a22975c7cc9 100644 --- a/fs/xfs/xfs_iomap.c +++ b/fs/xfs/xfs_iomap.c @@ -1121,7 +1121,7 @@ xfs_atomic_write_cow_iomap_begin( return -EAGAIN; trace_xfs_iomap_atomic_write_cow(ip, offset, length); - +retry: xfs_ilock(ip, XFS_ILOCK_EXCL); if (!ip->i_cowfp) { @@ -1132,6 +1132,8 @@ xfs_atomic_write_cow_iomap_begin( if (!xfs_iext_lookup_extent(ip, ip->i_cowfp, offset_fsb, &icur, &cmap)) cmap.br_startoff = end_fsb; if (cmap.br_startoff <= offset_fsb) { + if (isnullstartblock(cmap.br_startblock)) + goto convert_delay; xfs_trim_extent(&cmap, offset_fsb, count_fsb); goto found; } @@ -1160,8 +1162,10 @@ xfs_atomic_write_cow_iomap_begin( if (!xfs_iext_lookup_extent(ip, ip->i_cowfp, offset_fsb, &icur, &cmap)) cmap.br_startoff = end_fsb; if (cmap.br_startoff <= offset_fsb) { - xfs_trim_extent(&cmap, offset_fsb, count_fsb); xfs_trans_cancel(tp); + if (isnullstartblock(cmap.br_startblock)) + goto convert_delay; + xfs_trim_extent(&cmap, offset_fsb, count_fsb); goto found; } @@ -1201,6 +1205,19 @@ xfs_atomic_write_cow_iomap_begin( xfs_iunlock(ip, XFS_ILOCK_EXCL); return xfs_bmbt_to_iomap(ip, iomap, &cmap, flags, IOMAP_F_SHARED, seq); +convert_delay: + xfs_iunlock(ip, XFS_ILOCK_EXCL); + error = xfs_bmapi_convert_delalloc(ip, XFS_COW_FORK, offset, iomap, + NULL); + if (error) + return error; + + /* + * Try the lookup again, because the delalloc conversion might have + * turned the COW mapping into unwritten, but we need it to be in + * written state. + */ + goto retry; out_unlock: xfs_iunlock(ip, XFS_ILOCK_EXCL); return error; -- 2.51.0