From patchwork Mon Nov 16 14:57:56 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 11909059 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=-12.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 D4DBAC82579 for ; Mon, 16 Nov 2020 15:01:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A0366206B7 for ; Mon, 16 Nov 2020 15:01:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="KMc7aGpw" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731034AbgKPPBQ (ORCPT ); Mon, 16 Nov 2020 10:01:16 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49232 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731062AbgKPO74 (ORCPT ); Mon, 16 Nov 2020 09:59:56 -0500 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D088DC0613D2; Mon, 16 Nov 2020 06:59:55 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Transfer-Encoding:MIME-Version: References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To: Content-Type:Content-ID:Content-Description; bh=zd1S9ob6uvhOklVRkrOeSjqFIX0gjs8FIGa+SnPo4cs=; b=KMc7aGpwgD+lz4Ap0QfJBSwvVZ iRElJGYPaXtvm2l9EE0QgJGZsLEMjMUI0TNdT5TzgHVBvn7Zkv6OmXwKmUcW5NNi2zdVuHdJ996Ac OwvmfOLIphJ8QVS1fk75k9Alf/HM3+yte1sC2Cw0u4ljnVUY+8L5tiyT4eYi4wo/A+Hc0PUaBTH0m JjNk8TEGb2obEe56crgiqesbff6AXgdDuyaMinswXcIOBb/Qar6Y3kJ12qgYT1OQ66sP9wZekpAU1 SHqAycA5BdeglD3wmyoPmCAafo1AzTrZyURw0bkbcfVj6u7/3WjF0X4AlPQXPGdveo8XwIrYcJs7A LRojdTPA==; Received: from [2001:4bb8:180:6600:255b:7def:a93:4a09] (helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1kefyq-0004E0-6d; Mon, 16 Nov 2020 14:59:44 +0000 From: Christoph Hellwig To: Jens Axboe Cc: Justin Sanders , Josef Bacik , Ilya Dryomov , Jack Wang , "Michael S. Tsirkin" , Jason Wang , Paolo Bonzini , Stefan Hajnoczi , Konrad Rzeszutek Wilk , =?utf-8?q?Roger_Pau_Monn?= =?utf-8?q?=C3=A9?= , Minchan Kim , Mike Snitzer , Song Liu , "Martin K. Petersen" , dm-devel@redhat.com, linux-block@vger.kernel.org, drbd-dev@lists.linbit.com, nbd@other.debian.org, ceph-devel@vger.kernel.org, xen-devel@lists.xenproject.org, linux-raid@vger.kernel.org, linux-nvme@lists.infradead.org, linux-scsi@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: [PATCH 65/78] dm: remove the block_device reference in struct mapped_device Date: Mon, 16 Nov 2020 15:57:56 +0100 Message-Id: <20201116145809.410558-66-hch@lst.de> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201116145809.410558-1-hch@lst.de> References: <20201116145809.410558-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org. See http://www.infradead.org/rpr.html Precedence: bulk List-ID: X-Mailing-List: ceph-devel@vger.kernel.org Get rid of the long-lasting struct block_device reference in struct mapped_device. The only remaining user is the freeze code, where we can trivially look up the block device at freeze time and release the reference at thaw time. Signed-off-by: Christoph Hellwig Reviewed-by: Hannes Reinecke --- drivers/md/dm-core.h | 2 -- drivers/md/dm.c | 22 +++++++++++----------- 2 files changed, 11 insertions(+), 13 deletions(-) diff --git a/drivers/md/dm-core.h b/drivers/md/dm-core.h index d522093cb39dda..b1b400ed76fe90 100644 --- a/drivers/md/dm-core.h +++ b/drivers/md/dm-core.h @@ -107,8 +107,6 @@ struct mapped_device { /* kobject and completion */ struct dm_kobject_holder kobj_holder; - struct block_device *bdev; - struct dm_stats stats; /* for blk-mq request-based DM support */ diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 6d7eb72d41f9ea..c789ffea2badde 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1744,11 +1744,6 @@ static void cleanup_mapped_device(struct mapped_device *md) cleanup_srcu_struct(&md->io_barrier); - if (md->bdev) { - bdput(md->bdev); - md->bdev = NULL; - } - mutex_destroy(&md->suspend_lock); mutex_destroy(&md->type_lock); mutex_destroy(&md->table_devices_lock); @@ -1840,10 +1835,6 @@ static struct mapped_device *alloc_dev(int minor) if (!md->wq) goto bad; - md->bdev = bdget_disk(md->disk, 0); - if (!md->bdev) - goto bad; - dm_stats_init(&md->stats); /* Populate the mapping, nobody knows we exist yet */ @@ -2384,12 +2375,17 @@ struct dm_table *dm_swap_table(struct mapped_device *md, struct dm_table *table) */ static int lock_fs(struct mapped_device *md) { + struct block_device *bdev; int r; WARN_ON(md->frozen_sb); - md->frozen_sb = freeze_bdev(md->bdev); + bdev = bdget_disk(md->disk, 0); + if (!bdev) + return -ENOMEM; + md->frozen_sb = freeze_bdev(bdev); if (IS_ERR(md->frozen_sb)) { + bdput(bdev); r = PTR_ERR(md->frozen_sb); md->frozen_sb = NULL; return r; @@ -2402,10 +2398,14 @@ static int lock_fs(struct mapped_device *md) static void unlock_fs(struct mapped_device *md) { + struct block_device *bdev; + if (!test_bit(DMF_FROZEN, &md->flags)) return; - thaw_bdev(md->bdev, md->frozen_sb); + bdev = md->frozen_sb->s_bdev; + thaw_bdev(bdev, md->frozen_sb); + bdput(bdev); md->frozen_sb = NULL; clear_bit(DMF_FROZEN, &md->flags); }