From mboxrd@z Thu Jan 1 00:00:00 1970 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=-17.5 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, USER_AGENT_SANE_1 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 CDFFCC433DB for ; Thu, 7 Jan 2021 21:53:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 983F8235FD for ; Thu, 7 Jan 2021 21:53:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726666AbhAGVxp (ORCPT ); Thu, 7 Jan 2021 16:53:45 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:52797 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726386AbhAGVxp (ORCPT ); Thu, 7 Jan 2021 16:53:45 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1610056338; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=e/5UZ6AQFSYK1yZlQH6NOXZBaNAtgnhFETBa2236qEo=; b=YA8tpnP4XU9YyQG75nO/CQjiBAyqQIDUy0BQQxhOziQZt4ytUbsy0AQq1Q0q/KaktmdFer 6zWFUTDZAhJxnr/6PEJ/Aj242wofy9t52J6Q4epIOLh0qYNu7ZCzUnMMWSsidFmIwLX+B8 epo0AEEpyKjL7glkCtv9aEWshz5nb+w= 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-264-YeozKnpqN7mdvu6h9PU5zA-1; Thu, 07 Jan 2021 16:52:17 -0500 X-MC-Unique: YeozKnpqN7mdvu6h9PU5zA-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 06F128049C1; Thu, 7 Jan 2021 21:52:16 +0000 (UTC) Received: from localhost (unknown [10.18.25.174]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 646AB60CC3; Thu, 7 Jan 2021 21:52:11 +0000 (UTC) Date: Thu, 7 Jan 2021 16:52:10 -0500 From: Mike Snitzer To: Jeffle Xu Cc: linux-block@vger.kernel.org, dm-devel@redhat.com, io-uring@vger.kernel.org Subject: Re: [PATCH RFC 4/7] block: define blk_qc_t as uintptr_t Message-ID: <20210107215210.GD21239@redhat.com> References: <20201223112624.78955-1-jefflexu@linux.alibaba.com> <20201223112624.78955-5-jefflexu@linux.alibaba.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201223112624.78955-5-jefflexu@linux.alibaba.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On Wed, Dec 23 2020 at 6:26am -0500, Jeffle Xu wrote: > To support iopoll for bio-based device, the returned cookie is actually > a pointer to an implementation specific object, e.g. an object > maintaining all split bios. > > In such case, blk_qc_t should be large enough to contain one pointer, > for which uintptr_t is used here. Since uintptr_t is actually an integer > type in essence, there's no need of type casting in the original mq > path, while type casting is indeed needed in bio-based routine. > > Signed-off-by: Jeffle Xu > --- > include/linux/types.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/include/linux/types.h b/include/linux/types.h > index da5ca7e1bea9..f6301014a459 100644 > --- a/include/linux/types.h > +++ b/include/linux/types.h > @@ -126,7 +126,7 @@ typedef u64 sector_t; > typedef u64 blkcnt_t; > > /* cookie used for IO polling */ > -typedef unsigned int blk_qc_t; > +typedef uintptr_t blk_qc_t; > > /* > * The type of an index into the pagecache. I'd just fold this into patch 6.. not seeing benefit to having this be separate. Patch 6's header needs a lot more detail anyway so..