From patchwork Thu Mar 18 16:48:25 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ming Lei X-Patchwork-Id: 12148611 X-Patchwork-Delegate: snitzer@redhat.com 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=-16.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 D7953C433E0 for ; Thu, 18 Mar 2021 16:50:06 +0000 (UTC) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [216.205.24.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 7B2D764F11 for ; Thu, 18 Mar 2021 16:50:06 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7B2D764F11 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=tempfail smtp.mailfrom=dm-devel-bounces@redhat.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1616086205; h=from:from:sender:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:list-id:list-help: list-unsubscribe:list-subscribe:list-post; bh=j/15/r0K9wiCAgIZrfL/7IyYJDlC5jCHr7qjYC2y/PY=; b=F3EjJglOITjvoNypweL6ZV9v6M9iePS+9wwwMYVMGrXpo0wNdFMfwxpc4Cj8JEhDX2x87t nZsUyWaBxcc9YM/m3jV+hcf9Ptt8wXY4OSCsvqV8Toe/RH2uVKQxGggf2wyO+fc1we5fgN ww4fLJWpRHxQsSllYziSj/hr6aWjb60= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-587-fyPLjxUUP8ubug_XXloBCA-1; Thu, 18 Mar 2021 12:50:02 -0400 X-MC-Unique: fyPLjxUUP8ubug_XXloBCA-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id C529018C8C00; Thu, 18 Mar 2021 16:49:56 +0000 (UTC) Received: from colo-mx.corp.redhat.com (colo-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.21]) by smtp.corp.redhat.com (Postfix) with ESMTPS id A083150415; Thu, 18 Mar 2021 16:49:56 +0000 (UTC) Received: from lists01.pubmisc.prod.ext.phx2.redhat.com (lists01.pubmisc.prod.ext.phx2.redhat.com [10.5.19.33]) by colo-mx.corp.redhat.com (Postfix) with ESMTP id 6743A4A7C8; Thu, 18 Mar 2021 16:49:56 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) by lists01.pubmisc.prod.ext.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id 12IGnscc030658 for ; Thu, 18 Mar 2021 12:49:54 -0400 Received: by smtp.corp.redhat.com (Postfix) id 3FE8310023BE; Thu, 18 Mar 2021 16:49:54 +0000 (UTC) Received: from localhost (ovpn-12-24.pek2.redhat.com [10.72.12.24]) by smtp.corp.redhat.com (Postfix) with ESMTP id 8FEF410027A5; Thu, 18 Mar 2021 16:49:53 +0000 (UTC) From: Ming Lei To: Jens Axboe Date: Fri, 19 Mar 2021 00:48:25 +0800 Message-Id: <20210318164827.1481133-12-ming.lei@redhat.com> In-Reply-To: <20210318164827.1481133-1-ming.lei@redhat.com> References: <20210318164827.1481133-1-ming.lei@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-loop: dm-devel@redhat.com Cc: linux-block@vger.kernel.org, Jeffle Xu , dm-devel@redhat.com, Christoph Hellwig , Mike Snitzer Subject: [dm-devel] [RFC PATCH V2 11/13] block: add poll_capable method to support bio-based IO polling X-BeenThere: dm-devel@redhat.com X-Mailman-Version: 2.1.12 Precedence: junk List-Id: device-mapper development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=dm-devel-bounces@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com From: Jeffle Xu This method can be used to check if bio-based device supports IO polling or not. For mq devices, checking for hw queue in polling mode is adequate, while the sanity check shall be implementation specific for bio-based devices. For example, dm device needs to check if all underlying devices are capable of IO polling. Though bio-based device may have done the sanity check during the device initialization phase, cacheing the result of this sanity check (such as by cacheing in the queue_flags) may not work. Because for dm devices, users could change the state of the underlying devices through '/sys/block//io_poll', bypassing the dm device above. In this case, the cached result of the very beginning sanity check could be out-of-date. Thus the sanity check needs to be done every time 'io_poll' is to be modified. Signed-off-by: Jeffle Xu --- block/blk-sysfs.c | 14 +++++++++++--- include/linux/blkdev.h | 1 + 2 files changed, 12 insertions(+), 3 deletions(-) diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index 0f4f0c8a7825..367c1d9a55c6 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -426,9 +426,17 @@ static ssize_t queue_poll_store(struct request_queue *q, const char *page, unsigned long poll_on; ssize_t ret; - if (!q->tag_set || q->tag_set->nr_maps <= HCTX_TYPE_POLL || - !q->tag_set->map[HCTX_TYPE_POLL].nr_queues) - return -EINVAL; + if (queue_is_mq(q)) { + if (!q->tag_set || q->tag_set->nr_maps <= HCTX_TYPE_POLL || + !q->tag_set->map[HCTX_TYPE_POLL].nr_queues) + return -EINVAL; + } else { + struct gendisk *disk = queue_to_disk(q); + + if (!disk->fops->poll_capable || + !disk->fops->poll_capable(disk)) + return -EINVAL; + } ret = queue_var_store(&poll_on, page, count); if (ret < 0) diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index bfab74b45f15..a46f975f2a2f 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1881,6 +1881,7 @@ struct block_device_operations { int (*report_zones)(struct gendisk *, sector_t sector, unsigned int nr_zones, report_zones_cb cb, void *data); char *(*devnode)(struct gendisk *disk, umode_t *mode); + bool (*poll_capable)(struct gendisk *disk); struct module *owner; const struct pr_ops *pr_ops; };