From patchwork Wed Nov 4 09:18:41 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jan Kara X-Patchwork-Id: 7548471 Return-Path: X-Original-To: patchwork-linux-fsdevel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 6E2E39F2F7 for ; Wed, 4 Nov 2015 09:19:37 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id A28482060D for ; Wed, 4 Nov 2015 09:19:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CA184205EE for ; Wed, 4 Nov 2015 09:19:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932523AbbKDJTI (ORCPT ); Wed, 4 Nov 2015 04:19:08 -0500 Received: from mx2.suse.de ([195.135.220.15]:47974 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932241AbbKDJS6 (ORCPT ); Wed, 4 Nov 2015 04:18:58 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay1.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 30ABBAC9E; Wed, 4 Nov 2015 09:18:39 +0000 (UTC) Received: by quack.suse.cz (Postfix, from userid 1000) id 945F380F24; Wed, 4 Nov 2015 10:18:55 +0100 (CET) From: Jan Kara To: axboe@kernel.dk Cc: LKML , linux-fsdevel@vger.kernel.org, Jan Kara Subject: [PATCH] block: Don't allow illegal discard requests Date: Wed, 4 Nov 2015 10:18:41 +0100 Message-Id: <1446628721-11030-1-git-send-email-jack@suse.com> X-Mailer: git-send-email 2.1.4 Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Currently blkdev_issue_discard() doesn't check that submitted discard request matches granularity required by the underlying device. Submitting such requests to the device can have unexpected consequences (e.g. brd driver just discards more / less data depending on how exactly the request is aligned). So test that submitted discard request has the granularity required by the driver. Signed-off-by: Jan Kara --- block/blk-lib.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/block/blk-lib.c b/block/blk-lib.c index bd40292e5009..7170d02e9e9a 100644 --- a/block/blk-lib.c +++ b/block/blk-lib.c @@ -61,6 +61,13 @@ int blkdev_issue_discard(struct block_device *bdev, sector_t sector, if (!blk_queue_discard(q)) return -EOPNOTSUPP; + if (q->limits.discard_granularity) { + unsigned int gran_sect = q->limits.discard_granularity >> 9; + + if (sector % gran_sect || nr_sects % gran_sect) + return -EINVAL; + } + if (flags & BLKDEV_DISCARD_SECURE) { if (!blk_queue_secdiscard(q)) return -EOPNOTSUPP;