From patchwork Thu Jul 15 18:39:57 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 478054 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=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, USER_AGENT_GIT autolearn=ham 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 C92CCC6377E for ; Thu, 15 Jul 2021 19:05:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B61B2613C4 for ; Thu, 15 Jul 2021 19:05:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242522AbhGOTHz (ORCPT ); Thu, 15 Jul 2021 15:07:55 -0400 Received: from mail.kernel.org ([198.145.29.99]:46412 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242503AbhGOTGx (ORCPT ); Thu, 15 Jul 2021 15:06:53 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 386B1613D4; Thu, 15 Jul 2021 19:03:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1626375787; bh=INyJeFAVFCMDDxPWIB66WGq+MIN1r+ZSRaBmZN4dAmU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=GJk26Q+CPvn34vrA2axvbH1YwiKetLB/J2g3CAv2X7jNFTEvV+mXgjh0MaxyaIExQ Q5rSCqXIUEEfjZ3wJINM8McmER3tY+ZEJehrpQDM9jE+NoH5enP6wKA4IHRAX16VM7 IRmVileBKopFSk6SMpQ6lBhD9msFyAWtKbUbZV7A= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Mikulas Patocka , Mike Snitzer Subject: [PATCH 5.12 235/242] dm writecache: write at least 4k when committing Date: Thu, 15 Jul 2021 20:39:57 +0200 Message-Id: <20210715182634.215340090@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210715182551.731989182@linuxfoundation.org> References: <20210715182551.731989182@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Mikulas Patocka commit 867de40c4c23e6d7f89f9ce4272a5d1b1484c122 upstream. SSDs perform badly with sub-4k writes (because they perfrorm read-modify-write internally), so make sure writecache writes at least 4k when committing. Fixes: 991bd8d7bc78 ("dm writecache: commit just one block, not a full page") Signed-off-by: Mikulas Patocka Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman --- drivers/md/dm-writecache.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) --- a/drivers/md/dm-writecache.c +++ b/drivers/md/dm-writecache.c @@ -532,7 +532,11 @@ static void ssd_commit_superblock(struct region.bdev = wc->ssd_dev->bdev; region.sector = 0; - region.count = wc->block_size >> SECTOR_SHIFT; + region.count = max(4096U, wc->block_size) >> SECTOR_SHIFT; + + if (unlikely(region.sector + region.count > wc->metadata_sectors)) + region.count = wc->metadata_sectors - region.sector; + region.sector += wc->start_sector; req.bi_op = REQ_OP_WRITE;