From mboxrd@z Thu Jan 1 00:00:00 1970 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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 26676C352A3 for ; Mon, 10 Feb 2020 13:18:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F246820842 for ; Mon, 10 Feb 2020 13:18:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581340695; bh=RC5LyErzA5QLiIz6fXV5CAXcGDg3k+bE+UcIo5ET3PU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=YsEvtwwbRzMmPKsCe1vvGAiEfyExe31URKUxI9XTNATH+mX/gGzTCg7l+TPd5C8ud ci8IuAy2fwUKmCG+jWqBtPaABm0f9c3gsxjzaq9b/yFr4td9FQ8Zi2NVnSDic1wDx7 tm5oCJjaaIAFrgZIwHzErKVuXpvNu0TCKO5EjzwI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731053AbgBJNSO (ORCPT ); Mon, 10 Feb 2020 08:18:14 -0500 Received: from mail.kernel.org ([198.145.29.99]:60534 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728952AbgBJMhy (ORCPT ); Mon, 10 Feb 2020 07:37:54 -0500 Received: from localhost (unknown [209.37.97.194]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 3911424687; Mon, 10 Feb 2020 12:37:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581338274; bh=RC5LyErzA5QLiIz6fXV5CAXcGDg3k+bE+UcIo5ET3PU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ARXYI+xvV+Hm+73v5Nkvq+GSGCf5COUe1TrWhWx6kWpCgvDJD8HKssvZODaSyL9gG JRDf6+u9FiMw0YCyfRSppzlUtFhYP9AltEjilt8oO3e7RLeYVyu5kS3mjo0pZiQWND oDTDBoKP0v6HDdeYhNF65PvP4+kJrCtKL+XBv9oE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Mike Snitzer Subject: [PATCH 5.4 132/309] dm thin metadata: use pool locking at end of dm_pool_metadata_close Date: Mon, 10 Feb 2020 04:31:28 -0800 Message-Id: <20200210122419.047329981@linuxfoundation.org> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200210122406.106356946@linuxfoundation.org> References: <20200210122406.106356946@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Mike Snitzer commit 44d8ebf436399a40fcd10dd31b29d37823d62fcc upstream. Ensure that the pool is locked during calls to __commit_transaction and __destroy_persistent_data_objects. Just being consistent with locking, but reality is dm_pool_metadata_close is called once pool is being destroyed so access to pool shouldn't be contended. Also, use pmd_write_lock_in_core rather than __pmd_write_lock in dm_pool_commit_metadata and rename __pmd_write_lock to pmd_write_lock_in_core -- there was no need for the alias. In addition, verify that the pool is locked in __commit_transaction(). Fixes: 873f258becca ("dm thin metadata: do not write metadata if no changes occurred") Cc: stable@vger.kernel.org Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman --- drivers/md/dm-thin-metadata.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) --- a/drivers/md/dm-thin-metadata.c +++ b/drivers/md/dm-thin-metadata.c @@ -387,16 +387,15 @@ static int subtree_equal(void *context, * Variant that is used for in-core only changes or code that * shouldn't put the pool in service on its own (e.g. commit). */ -static inline void __pmd_write_lock(struct dm_pool_metadata *pmd) +static inline void pmd_write_lock_in_core(struct dm_pool_metadata *pmd) __acquires(pmd->root_lock) { down_write(&pmd->root_lock); } -#define pmd_write_lock_in_core(pmd) __pmd_write_lock((pmd)) static inline void pmd_write_lock(struct dm_pool_metadata *pmd) { - __pmd_write_lock(pmd); + pmd_write_lock_in_core(pmd); if (unlikely(!pmd->in_service)) pmd->in_service = true; } @@ -831,6 +830,7 @@ static int __commit_transaction(struct d * We need to know if the thin_disk_superblock exceeds a 512-byte sector. */ BUILD_BUG_ON(sizeof(struct thin_disk_superblock) > 512); + BUG_ON(!rwsem_is_locked(&pmd->root_lock)); if (unlikely(!pmd->in_service)) return 0; @@ -953,6 +953,7 @@ int dm_pool_metadata_close(struct dm_poo return -EBUSY; } + pmd_write_lock_in_core(pmd); if (!dm_bm_is_read_only(pmd->bm) && !pmd->fail_io) { r = __commit_transaction(pmd); if (r < 0) @@ -961,6 +962,7 @@ int dm_pool_metadata_close(struct dm_poo } if (!pmd->fail_io) __destroy_persistent_data_objects(pmd); + pmd_write_unlock(pmd); kfree(pmd); return 0; @@ -1841,7 +1843,7 @@ int dm_pool_commit_metadata(struct dm_po * Care is taken to not have commit be what * triggers putting the thin-pool in-service. */ - __pmd_write_lock(pmd); + pmd_write_lock_in_core(pmd); if (pmd->fail_io) goto out;