From patchwork Thu Jul 2 08:49:16 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 11638311 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 834EE618 for ; Thu, 2 Jul 2020 08:49:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6B8EE2088E for ; Thu, 2 Jul 2020 08:49:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="QRLMMTFs" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726739AbgGBItY (ORCPT ); Thu, 2 Jul 2020 04:49:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51060 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725287AbgGBItY (ORCPT ); Thu, 2 Jul 2020 04:49:24 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5D2F9C08C5C1 for ; Thu, 2 Jul 2020 01:49:24 -0700 (PDT) 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=A/I1vcnEOWPovRd4d32sgJlzY0F1UatPERDEAW8X52Y=; b=QRLMMTFsc/svpBXpLjllssJp1+ whFAtpb9cPFE4gbAjV4byQETZOpwy3yZvBZ4JIJBVXghoI94dPMpwNB4OCJgn9TMwUK+2SrfNdG1V jg3MUWomq0PB6yRCaGhCr3y9oLJ+gd9mVmb4/xJOpZI30a6+amM0i0x6vyu4EkFzsFSDUXxz2jg4A F7S74CrHKkNuDx6oSX9Z+zzkQMWfwAovDr3STOEhc/o72IJYGP43Rn3Kk+hIITZeGRUqM2denlMIY dPyCwGA4swE1ZlBFvgC+GlREIv7cpBDa1rO6rY2q3SDKfs7hv0wuRNiBsJSOOq4Py/8LJXcuMmvRO wWj4GAuA==; Received: from [213.208.157.36] (helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1jquuH-0001VR-Ql; Thu, 02 Jul 2020 08:49:22 +0000 From: Christoph Hellwig To: Jens Axboe Cc: Tejun Heo , linux-block@vger.kernel.org Subject: [PATCH 1/4] block: simplify the restart case in __blkdev_get Date: Thu, 2 Jul 2020 10:49:16 +0200 Message-Id: <20200702084919.3720275-2-hch@lst.de> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200702084919.3720275-1-hch@lst.de> References: <20200702084919.3720275-1-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 Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Insted of duplicating all the cleanup logic jump to the code that cleans up anyway, and restart after that. Signed-off-by: Christoph Hellwig --- fs/block_dev.c | 25 ++++++++++--------------- 1 file changed, 10 insertions(+), 15 deletions(-) diff --git a/fs/block_dev.c b/fs/block_dev.c index 2d2fcb50e78eac..175161359664ca 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -1533,7 +1533,7 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part) int ret; int partno; int perm = 0; - bool first_open = false; + bool first_open = false, need_restart; if (mode & FMODE_READ) perm |= MAY_READ; @@ -1549,7 +1549,7 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part) } restart: - + need_restart = false; ret = -ENXIO; disk = bdev_get_gendisk(bdev, &partno); if (!disk) @@ -1572,19 +1572,12 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part) ret = 0; if (disk->fops->open) { ret = disk->fops->open(bdev, mode); - if (ret == -ERESTARTSYS) { - /* Lost a race with 'disk' being - * deleted, try again. - * See md.c - */ - disk_put_part(bdev->bd_part); - bdev->bd_part = NULL; - bdev->bd_disk = NULL; - mutex_unlock(&bdev->bd_mutex); - disk_unblock_events(disk); - put_disk_and_module(disk); - goto restart; - } + /* + * If we lost a race with 'disk' being deleted, + * try again. See md.c + */ + if (ret == -ERESTARTSYS) + need_restart = true; } if (!ret) { @@ -1663,6 +1656,8 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part) mutex_unlock(&bdev->bd_mutex); disk_unblock_events(disk); put_disk_and_module(disk); + if (need_restart) + goto restart; out: return ret;