From patchwork Sun Jan 24 10:02:40 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 12042211 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 8FEDAC433DB for ; Sun, 24 Jan 2021 10:08:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 63613225A9 for ; Sun, 24 Jan 2021 10:08:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726841AbhAXKH5 (ORCPT ); Sun, 24 Jan 2021 05:07:57 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47806 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726793AbhAXKG6 (ORCPT ); Sun, 24 Jan 2021 05:06:58 -0500 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 08E61C061573; Sun, 24 Jan 2021 02:06:05 -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=/EYk+0P96lR/mC5Sas0GCCBCqytAW3UF4FS5EfHCsd8=; b=tHgzV1Qgpoq+wIM+i7/OFCqeVb AMG4zclGEMAKTAHZY3WwOem5zSbUy6r3io0PIIqV4pb4b4Lo+9XtQFTv2WL8EZhU6W+AtW7XunQab l1IAC7bUoJJqeEZBZQekM8VGbfJKeNhM8bMHuUxBjrudTqDcsW9CATlcTX3nFWiVAPdVZ6UR5ugni +tmAjPT0SMOUEF9vlGJkCPwIQMq3GuZd7b8oUSF2x0H3iNAUXswl9+lb8OspDSXu/+FWJfikFVpsG 7ko98GKzvF/nHFIgPr1x8xai6rjCkr7xoEFF++ACCF8G/XPAaiT+F0QGvj+5bA929d1Z7O0AeuNU4 NzwXF9Ow==; Received: from [2001:4bb8:188:1954:a3b3:627f:702b:2136] (helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.94 #2 (Red Hat Linux)) id 1l3cHK-002qAP-RM; Sun, 24 Jan 2021 10:05:56 +0000 From: Christoph Hellwig To: Jens Axboe Cc: Tejun Heo , Coly Li , Song Liu , dm-devel@redhat.com, linux-bcache@vger.kernel.org, linux-raid@vger.kernel.org, linux-s390@vger.kernel.org, linux-block@vger.kernel.org Subject: [PATCH 09/10] block: remove DISK_PITER_REVERSE Date: Sun, 24 Jan 2021 11:02:40 +0100 Message-Id: <20210124100241.1167849-10-hch@lst.de> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210124100241.1167849-1-hch@lst.de> References: <20210124100241.1167849-1-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-block@vger.kernel.org There is good reason to iterate backwards when deleting all partitions in del_gendisk, just like we don't in blk_drop_partitions. Signed-off-by: Christoph Hellwig Acked-by: Tejun Heo --- block/genhd.c | 37 +++++++------------------------------ include/linux/genhd.h | 1 - 2 files changed, 7 insertions(+), 31 deletions(-) diff --git a/block/genhd.c b/block/genhd.c index 7094612c7510a8..1832add5c73849 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -184,24 +184,13 @@ static struct block_device *__disk_get_part(struct gendisk *disk, int partno) void disk_part_iter_init(struct disk_part_iter *piter, struct gendisk *disk, unsigned int flags) { - struct disk_part_tbl *ptbl; - - rcu_read_lock(); - ptbl = rcu_dereference(disk->part_tbl); - piter->disk = disk; piter->part = NULL; - - if (flags & DISK_PITER_REVERSE) - piter->idx = ptbl->len - 1; - else if (flags & (DISK_PITER_INCL_PART0 | DISK_PITER_INCL_EMPTY_PART0)) + if (flags & (DISK_PITER_INCL_PART0 | DISK_PITER_INCL_EMPTY_PART0)) piter->idx = 0; else piter->idx = 1; - piter->flags = flags; - - rcu_read_unlock(); } /** @@ -216,7 +205,6 @@ void disk_part_iter_init(struct disk_part_iter *piter, struct gendisk *disk, struct block_device *disk_part_iter_next(struct disk_part_iter *piter) { struct disk_part_tbl *ptbl; - int inc, end; /* put the last partition */ disk_part_iter_exit(piter); @@ -225,21 +213,8 @@ struct block_device *disk_part_iter_next(struct disk_part_iter *piter) rcu_read_lock(); ptbl = rcu_dereference(piter->disk->part_tbl); - /* determine iteration parameters */ - if (piter->flags & DISK_PITER_REVERSE) { - inc = -1; - if (piter->flags & (DISK_PITER_INCL_PART0 | - DISK_PITER_INCL_EMPTY_PART0)) - end = -1; - else - end = 0; - } else { - inc = 1; - end = ptbl->len; - } - /* iterate to the next partition */ - for (; piter->idx != end; piter->idx += inc) { + for (; piter->idx != ptbl->len; piter->idx += 1) { struct block_device *part; part = rcu_dereference(ptbl->part[piter->idx]); @@ -257,7 +232,10 @@ struct block_device *disk_part_iter_next(struct disk_part_iter *piter) continue; } - piter->idx += inc; + piter->part = bdgrab(part); + if (!piter->part) + continue; + piter->idx += 1; break; } @@ -781,8 +759,7 @@ void del_gendisk(struct gendisk *disk) down_write(&bdev_lookup_sem); /* invalidate stuff */ - disk_part_iter_init(&piter, disk, - DISK_PITER_INCL_EMPTY | DISK_PITER_REVERSE); + disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY); while ((part = disk_part_iter_next(&piter))) { invalidate_partition(part); delete_partition(part); diff --git a/include/linux/genhd.h b/include/linux/genhd.h index 670eaef0e87622..51609133c9a347 100644 --- a/include/linux/genhd.h +++ b/include/linux/genhd.h @@ -218,7 +218,6 @@ void disk_uevent(struct gendisk *disk, enum kobject_action action); /* * Smarter partition iterator without context limits. */ -#define DISK_PITER_REVERSE (1 << 0) /* iterate in the reverse direction */ #define DISK_PITER_INCL_EMPTY (1 << 1) /* include 0-sized parts */ #define DISK_PITER_INCL_PART0 (1 << 2) /* include partition 0 */ #define DISK_PITER_INCL_EMPTY_PART0 (1 << 3) /* include empty partition 0 */