From patchwork Mon Nov 16 14:57:42 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 324640 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 706D2C82550 for ; Mon, 16 Nov 2020 15:00:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 31D8124199 for ; Mon, 16 Nov 2020 15:00:18 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="cAGojbsp" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730989AbgKPO7h (ORCPT ); Mon, 16 Nov 2020 09:59:37 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49152 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730956AbgKPO7e (ORCPT ); Mon, 16 Nov 2020 09:59:34 -0500 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 90444C0613D3; Mon, 16 Nov 2020 06:59:34 -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=G/1St6AKcpua/c8qIsi4IENao5SAFeNTsicWvdwJGKA=; b=cAGojbspvBWLkhCqOD3ExDenEy hsbkbexTXugOliCWH3wwCYbwxpTnVtQvHgLrTwVXI7TrPcURLYokj4yyAxwxnnG9BNHdwGnWa8IJp dYa+F3Gfpccic7jbe1Y8gwBkRHM+oEunUjIG3WI5m5UONDYn9V9VBRbIHSxNQhGM/1JRKjD49Xkx0 0pBHsNUFU/UPntTwF6P/GQ0sJw5J/q2+RSCrhYYdXSuMK/KdhdMuk9LCQiscZHIVOefv7v6KYkI86 OblDiO3zLuOm232EWEv9/powerW9w8u+EGbE5WQyTuk7Cg+xA59dLIs/S/NWj2DLWnBN8UoHAueaN ZQN++kOA==; 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 1kefyU-00043H-JC; Mon, 16 Nov 2020 14:59:23 +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=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, Hannes Reinecke Subject: [PATCH 51/78] z2ram: use separate gendisk for the different modes Date: Mon, 16 Nov 2020 15:57:42 +0100 Message-Id: <20201116145809.410558-52-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 Use separate gendisks (which share a tag_set) for the different operating modes instead of redirecting the gendisk lookup using a probe callback. This avoids potential problems with aliased block_device instances and will eventually allow for removing the blk_register_region framework. Signed-off-by: Christoph Hellwig Reviewed-by: Hannes Reinecke --- drivers/block/z2ram.c | 100 ++++++++++++++++++++++++------------------ 1 file changed, 58 insertions(+), 42 deletions(-) diff --git a/drivers/block/z2ram.c b/drivers/block/z2ram.c index eafecc9a72b38d..c1d20818e64920 100644 --- a/drivers/block/z2ram.c +++ b/drivers/block/z2ram.c @@ -63,7 +63,7 @@ static int current_device = -1; static DEFINE_SPINLOCK(z2ram_lock); -static struct gendisk *z2ram_gendisk; +static struct gendisk *z2ram_gendisk[Z2MINOR_COUNT]; static blk_status_t z2_queue_rq(struct blk_mq_hw_ctx *hctx, const struct blk_mq_queue_data *bd) @@ -283,7 +283,7 @@ static int z2_open(struct block_device *bdev, fmode_t mode) current_device = device; z2ram_size <<= Z2RAM_CHUNKSHIFT; - set_capacity(z2ram_gendisk, z2ram_size >> 9); + set_capacity(z2ram_gendisk[device], z2ram_size >> 9); } mutex_unlock(&z2ram_mutex); @@ -315,71 +315,87 @@ static const struct block_device_operations z2_fops = { .release = z2_release, }; -static struct kobject *z2_find(dev_t dev, int *part, void *data) -{ - *part = 0; - return get_disk_and_module(z2ram_gendisk); -} - -static struct request_queue *z2_queue; static struct blk_mq_tag_set tag_set; static const struct blk_mq_ops z2_mq_ops = { .queue_rq = z2_queue_rq, }; +static int z2ram_register_disk(int minor) +{ + struct request_queue *q; + struct gendisk *disk; + + disk = alloc_disk(1); + if (!disk) + return -ENOMEM; + + q = blk_mq_init_queue(&tag_set); + if (IS_ERR(q)) { + put_disk(disk); + return PTR_ERR(q); + } + + disk->major = Z2RAM_MAJOR; + disk->first_minor = minor; + disk->fops = &z2_fops; + if (minor) + sprintf(disk->disk_name, "z2ram%d", minor); + else + sprintf(disk->disk_name, "z2ram"); + disk->queue = q; + + z2ram_gendisk[minor] = disk; + add_disk(disk); + return 0; +} + static int __init z2_init(void) { - int ret; + int ret, i; if (!MACH_IS_AMIGA) return -ENODEV; - ret = -EBUSY; if (register_blkdev(Z2RAM_MAJOR, DEVICE_NAME)) - goto err; - - ret = -ENOMEM; - z2ram_gendisk = alloc_disk(1); - if (!z2ram_gendisk) - goto out_disk; - - z2_queue = blk_mq_init_sq_queue(&tag_set, &z2_mq_ops, 16, - BLK_MQ_F_SHOULD_MERGE); - if (IS_ERR(z2_queue)) { - ret = PTR_ERR(z2_queue); - z2_queue = NULL; - goto out_queue; + return -EBUSY; + + tag_set.ops = &z2_mq_ops; + tag_set.nr_hw_queues = 1; + tag_set.nr_maps = 1; + tag_set.queue_depth = 16; + tag_set.numa_node = NUMA_NO_NODE; + tag_set.flags = BLK_MQ_F_SHOULD_MERGE; + ret = blk_mq_alloc_tag_set(&tag_set); + if (ret) + goto out_unregister_blkdev; + + for (i = 0; i < Z2MINOR_COUNT; i++) { + ret = z2ram_register_disk(i); + if (ret && i == 0) + goto out_free_tagset; } - z2ram_gendisk->major = Z2RAM_MAJOR; - z2ram_gendisk->first_minor = 0; - z2ram_gendisk->fops = &z2_fops; - sprintf(z2ram_gendisk->disk_name, "z2ram"); - - z2ram_gendisk->queue = z2_queue; - add_disk(z2ram_gendisk); - blk_register_region(MKDEV(Z2RAM_MAJOR, 0), Z2MINOR_COUNT, THIS_MODULE, - z2_find, NULL, NULL); - return 0; -out_queue: - put_disk(z2ram_gendisk); -out_disk: +out_free_tagset: + blk_mq_free_tag_set(&tag_set); +out_unregister_blkdev: unregister_blkdev(Z2RAM_MAJOR, DEVICE_NAME); -err: return ret; } static void __exit z2_exit(void) { int i, j; - blk_unregister_region(MKDEV(Z2RAM_MAJOR, 0), Z2MINOR_COUNT); + unregister_blkdev(Z2RAM_MAJOR, DEVICE_NAME); - del_gendisk(z2ram_gendisk); - put_disk(z2ram_gendisk); - blk_cleanup_queue(z2_queue); + + for (i = 0; i < Z2MINOR_COUNT; i++) { + del_gendisk(z2ram_gendisk[i]); + blk_cleanup_queue(z2ram_gendisk[i]->queue); + put_disk(z2ram_gendisk[i]); + } blk_mq_free_tag_set(&tag_set); if (current_device != -1) {