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 4B03F1D86FF; Tue, 11 Nov 2025 01:44:38 +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=1762825478; cv=none; b=EHvYcHz7JURm0wtRU62gBTlaF+a1w9DcZnlFCwDR6WMLXl012zYOw1Skwv15AA5MeiBZMzmGGOg8WrEHr0peXc8PrQbpSdyJ1w/tZDfkqFZStm+LldD6H4d6zkaCwGjZQEIK1Ueb/gS5n++NwR3g58WRfRwNkeEKmK4BhzBwBEY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762825478; c=relaxed/simple; bh=atZlN0nBYw60VEBdK/U7BeDPTajCJSvMoRluLKegocQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=oS1a6aC0ZHQrFrLLf89hocSitMqweDyLdrQrljnfZ6aJpSIWD1fRTRoKt+TP2EWkM67YVQNV4wez50Np4VDUNLE3CIaM1WIaRkC+V0uNUsWZpWRP/cMyfT6H3ZhLTU8rwGg2okvQi+Q/0BEqnq27FjCzjy2ff/azR9YMK9qPTIc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=dQKVnUvg; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="dQKVnUvg" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DBE66C4CEF5; Tue, 11 Nov 2025 01:44:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1762825478; bh=atZlN0nBYw60VEBdK/U7BeDPTajCJSvMoRluLKegocQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=dQKVnUvgCXL3eo77VUWbAJLDP0a2bjifsiQFcNjY6ou92zi1WjVUFJdsBa4bc8pKa VsojUQzT45Lr7824YOBCsthFqGork28kibO9utMD8tGw3Y5rmza70I7r/DGUibX+0B +HkV7e1D/e1d8+yDeSfJRVYgutAS1t8eQ0vYFPaM= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, "Darrick J. Wong" , John Garry , Carlos Maiolino Subject: [PATCH 6.17 820/849] xfs: fix delalloc write failures in software-provided atomic writes Date: Tue, 11 Nov 2025 09:46:30 +0900 Message-ID: <20251111004556.249808619@linuxfoundation.org> X-Mailer: git-send-email 2.51.2 In-Reply-To: <20251111004536.460310036@linuxfoundation.org> References: <20251111004536.460310036@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.17-stable review patch. If anyone has any objections, please let me know. ------------------ From: Darrick J. Wong commit 8d54eacd82a0623a963e0c150ad3b02970638b0d upstream. 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 Signed-off-by: Greg Kroah-Hartman --- fs/xfs/xfs_iomap.c | 21 +++++++++++++++++++-- 1 file changed, 19 insertions(+), 2 deletions(-) --- 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 @@ found: 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;