From patchwork Fri Apr 16 03:05:24 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Damien Le Moal X-Patchwork-Id: 12206591 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-11.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 924D7C433ED for ; Fri, 16 Apr 2021 03:05:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6CE2361152 for ; Fri, 16 Apr 2021 03:05:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237292AbhDPDF4 (ORCPT ); Thu, 15 Apr 2021 23:05:56 -0400 Received: from esa3.hgst.iphmx.com ([216.71.153.141]:63371 "EHLO esa3.hgst.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234751AbhDPDFz (ORCPT ); Thu, 15 Apr 2021 23:05:55 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=wdc.com; i=@wdc.com; q=dns/txt; s=dkim.wdc.com; t=1618542330; x=1650078330; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=vUztHQeoC7q+dlfBS4+pbWv7aImp+UXJRbacb2BFxI8=; b=DqNG00SIyRf5dUHR46SUfQZXuQVOwuY2+kATozprSlGw0ax3NRa8hKjW ZRUdEfTJqQ65qDsNxTZPqyaofawIHXYEfnWmNnTfD6ruXF1x4r9pHmKl6 GdZx2EtJDWeuzj1k85SAs6KbzqjKWwINPeqdBVJhAtvNN4+NMozSlSNfK kY86hGSah7Hld25qLt91ra56Wl8X63TKXHcRj8Aa8Pien8eEmXx+4KGa6 S+G5gxOuRu8fRi7sRoju2thqd/04+NCb1nGn/fCeJmldlHxJHtssqYb8e kzPACSSOvFZsiUYscIVeILz9YMzGOOypZPlHQjq+M/UirrCj0YkamcVmR g==; IronPort-SDR: BlLgXTtMDWfeVwZUUPg2+J3v5fhkcbdHXJ5N017M7Ar9ucFN1ynHUyTFGxF6OhodK5gZCcT204 9UOd37heNlCeFiF67xDuj6dxAMCv2HpL+gRh28thl27Qdry2pcs+bQ3zulBb5t2uBLv5c7pYuz trkhFAd/KGuo6bf2g+99YsF4YnhavvmKOI8VB6yPqK8+69LhLajDr76Wvn3s1qgBrf2kST6yIv iJyHR6jiKtzKGEpwLEqzWQvrnkxt6/QM/Kb3pSUyNB9uvGOqwwCdRSZVCDNwJbom7ls3J9qLwm 9rc= X-IronPort-AV: E=Sophos;i="5.82,226,1613404800"; d="scan'208";a="169567850" Received: from h199-255-45-15.hgst.com (HELO uls-op-cesaep02.wdc.com) ([199.255.45.15]) by ob1.hgst.iphmx.com with ESMTP; 16 Apr 2021 11:05:29 +0800 IronPort-SDR: 4hIfWk7dqM1i6o8CppCZiRBg+JyZk0DZ0y9DXTzSl4da20/Doi1EWrYf6F03TfFRyHr/Wc7v9u X1KRPm9Tkk2+2sVUrjQn+vmcgDOFttHK1qCsXjS836YFLnUwO9NKeU7w6N/VN33bbqH2EUJGZG 4bWwQ+6smbMegX2hQQjyehB/t+hyKorOpX5JUO3Szs1aNP3fllqhbF8n/j2UHgbzz/m1Z4B1rM YI/11ukia/3ylImRsA2APdOomTYbuWfc7M2zT8Zpjp9Icld7NYhSsnfXt27O9EvEC5S8WERpN8 DauQ5ZxEYMjfkWkoJ8qfY6oH Received: from uls-op-cesaip02.wdc.com ([10.248.3.37]) by uls-op-cesaep02.wdc.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 15 Apr 2021 19:44:48 -0700 IronPort-SDR: 5uaHx0ME4yfxIf/TiutCrTMnLjb2kBOpJtRTKSLg4tH5AbhRWHekMEEGKLa3AXqEYy3a31snCo ElUXAQxKJQa6aOhWFDCPzlc/IpBsAx5KR6EDXe2ZmlnAA88cCbpAMSRLACPaVf/fHSYLQd8IgO DxavW3RSuugPmrGUFvYDSFHbIBbCHilMvHw4PQpzJEgqusd0uGMzfwXRxK2a2urB4I+6r1cg8f s/TX9LXikk5YOZaAYTcUE+pTyB5gwDGLNtSP+JbbsKm5Z1xjY+x4TV2Bu/ZpK3jUK5XA0aSsC7 IoM= WDCIronportException: Internal Received: from washi.fujisawa.hgst.com ([10.149.53.254]) by uls-op-cesaip02.wdc.com with ESMTP; 15 Apr 2021 20:05:29 -0700 From: Damien Le Moal To: dm-devel@redhat.com, Mike Snitzer , linux-block@vger.kernel.org, Jens Axboe , linux-nvme@lists.infradead.org, Christoph Hellwig , linux-scsi@vger.kernel.org, "Martin K . Petersen" , linux-fsdevel@vger.kernel.org, linux-btrfs@vger.kernel.org, David Sterba , Josef Bacik Cc: Johannes Thumshirn , Shinichiro Kawasaki , Naohiro Aota Subject: [PATCH 0/4] Fix dm-crypt zoned block device support Date: Fri, 16 Apr 2021 12:05:24 +0900 Message-Id: <20210416030528.757513-1-damien.lemoal@wdc.com> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org Mike, Zone append BIOs (REQ_OP_ZONE_APPEND) always specify the start sector of the zone to be written instead of the actual location sector to write. The write location is determined by the device and returned to the host upon completion of the operation. This interface, while simple and efficient for writing into sequential zones of a zoned block device, is incompatible with the use of sector values to calculate a cypher block IV. All data written in a zone is encrypted using an IV calculated from the first sectors of the zone, but read operation will specify any sector within the zone, resulting in an IV mismatch between encryption and decryption. Reads fail in that case. Using a single sector value (e.g. the zone start sector) for all read and writes into a zone can solve this problem, but at the cost of weakening the cypher chosen by the user. Emulating zone append using regular writes would be another potential solution, but it is complex and would add a lot of overhead. Instead, to solve this problem, explicitly disable support for zone append operations in dm-crypt if the target was setup using a cypher IV mode using sector values. The null and random IV modes can still be used with zone append operations. This lack of support for zone append is exposed to the user by setting the dm-crypt target queue limit max_zone_append_sectors to 0. This change is done in patch 1 and 2. Patch 3 addresses btrfs-zoned case. Zone append write are used for all file data blocks write. The change introduced fails mounting a zoned btrfs volume if the underlying device max_zone_append_sectors limit is 0. Patch 4 fixes zonefs to fall back to using regular write when max_zone_append_sectors is 0. Overall, these changes do not break user space: 1) There is no interface allowing a user to use zone append write without a file system. So applications using directly a raw dm-crypt device will continue working using regular write operations. 2) btrfs zoned support was added in 5.12. Anybody trying btrfs-zoned on top of dm-crypt would have faced the read failures already. So there are no existing deployments to preserve. Same for zonefs. For file systems, using zone append with encryption will need to be supported within the file system (e.g. fscrypt). In this case, cypher IV calculation can rely for instance on file block offsets as these are known before a zone append operation write these blocks to disk at unknown locations. Reviews and comments are very much welcome. Damien Le Moal (3): dm: Introduce zone append support control dm crypt: Fix zoned block device support zonefs: fix synchronous write to sequential zone files Johannes Thumshirn (1): btrfs: zoned: fail mount if the device does not support zone append drivers/md/dm-crypt.c | 48 ++++++++++++++++++++++++++++------- drivers/md/dm-table.c | 41 ++++++++++++++++++++++++++++++ fs/btrfs/zoned.c | 7 +++++ fs/zonefs/super.c | 16 +++++++++--- fs/zonefs/zonefs.h | 2 ++ include/linux/device-mapper.h | 6 +++++ 6 files changed, 107 insertions(+), 13 deletions(-)