From patchwork Thu Nov 26 13:03:47 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 11933501 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=-16.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,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 AFD0EC8301A for ; Thu, 26 Nov 2020 13:07:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 61BB521D7E for ; Thu, 26 Nov 2020 13:07:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="WipNHSiT" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389877AbgKZNG7 (ORCPT ); Thu, 26 Nov 2020 08:06:59 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53042 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388748AbgKZNG5 (ORCPT ); Thu, 26 Nov 2020 08:06:57 -0500 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9CE7FC0613D4; Thu, 26 Nov 2020 05:06:57 -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=qLuO7hD0TG0p9aylN+kHqBJxf5z3v4FVxxZ2M17hRmY=; b=WipNHSiTxaCf/i02olOf7S3b9k 7tumqyBklwAOPoXqVFvK7+2BEqr7y+sx5mtON0mAzzW3MNkz4zrs+oOdvLTnVFxaaiMonNJfLIy8Q mg8VT4WS4Ip5pd4gfxLpdNLWZoV6OX52On+8eE2jJEIcq7Cp7fEZVK3+QcKPIzI836DMs1oSmZ5mn CI/Pdisi9YSbIPpv0OjyO44mtEppEv4VK/NnydCG5MxTm7rW/g9HPg4FdYgn79eOrdDjUnC2veigu rt+xk0G2+KPdni2kRxB8tq3rtjl7wPFlb2kyTIaT/RrtRyhEAMkAYShxe7iJog3pPC+knYv7531E4 QzH7l/gQ==; Received: from [2001:4bb8:18c:1dd6:27b8:b8a1:c13e:ceb1] (helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1kiGyz-0003y8-VM; Thu, 26 Nov 2020 13:06:46 +0000 From: Christoph Hellwig To: Jens Axboe Cc: Tejun Heo , Josef Bacik , Coly Li , Mike Snitzer , Greg Kroah-Hartman , Jan Kara , Johannes Thumshirn , dm-devel@redhat.com, Jan Kara , linux-block@vger.kernel.org, linux-bcache@vger.kernel.org, linux-mtd@lists.infradead.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH 09/44] dm: remove the block_device reference in struct mapped_device Date: Thu, 26 Nov 2020 14:03:47 +0100 Message-Id: <20201126130422.92945-10-hch@lst.de> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201126130422.92945-1-hch@lst.de> References: <20201126130422.92945-1-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: linux-fsdevel@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 Acked-by: Mike Snitzer Reviewed-by: Hannes Reinecke --- drivers/md/dm-core.h | 2 -- drivers/md/dm.c | 25 ++++++++++++++----------- 2 files changed, 14 insertions(+), 13 deletions(-) diff --git a/drivers/md/dm-core.h b/drivers/md/dm-core.h index aace147effcacb..086d293c2b036c 100644 --- a/drivers/md/dm-core.h +++ b/drivers/md/dm-core.h @@ -102,8 +102,6 @@ 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 ab0a8335f098d9..48051db006f30c 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 */ @@ -2384,11 +2375,16 @@ 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(test_bit(DMF_FROZEN, &md->flags)); - r = freeze_bdev(md->bdev); + bdev = bdget_disk(md->disk, 0); + if (!bdev) + return -ENOMEM; + r = freeze_bdev(bdev); + bdput(bdev); if (!r) set_bit(DMF_FROZEN, &md->flags); return r; @@ -2396,9 +2392,16 @@ 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); + + bdev = bdget_disk(md->disk, 0); + if (!bdev) + return; + thaw_bdev(bdev); + bdput(bdev); clear_bit(DMF_FROZEN, &md->flags); }