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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id DB271C433EF for ; Fri, 25 Mar 2022 10:43:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240142AbiCYKpa (ORCPT ); Fri, 25 Mar 2022 06:45:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37660 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243015AbiCYKp2 (ORCPT ); Fri, 25 Mar 2022 06:45:28 -0400 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 82D8B85BEA for ; Fri, 25 Mar 2022 03:43:53 -0700 (PDT) Received: from fraeml742-chm.china.huawei.com (unknown [172.18.147.200]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4KPzCv0rJPz67ljv; Fri, 25 Mar 2022 18:41:31 +0800 (CST) Received: from lhreml710-chm.china.huawei.com (10.201.108.61) by fraeml742-chm.china.huawei.com (10.206.15.223) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Fri, 25 Mar 2022 11:43:50 +0100 Received: from localhost (10.122.247.231) by lhreml710-chm.china.huawei.com (10.201.108.61) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Fri, 25 Mar 2022 10:43:50 +0000 Date: Fri, 25 Mar 2022 10:43:48 +0000 From: Jonathan Cameron To: CC: Ben Widawsky , Dan Williams , Ira Weiny , Vishal Verma , Subject: Re: [PATCH v3 3/9] cxl/mbox: Move build of user mailbox cmd to a helper function Message-ID: <20220325104348.00002709@huawei.com> In-Reply-To: <20220324011126.1144504-4-alison.schofield@intel.com> References: <20220324011126.1144504-1-alison.schofield@intel.com> <20220324011126.1144504-4-alison.schofield@intel.com> Organization: Huawei Technologies R&D (UK) Ltd. X-Mailer: Claws Mail 4.0.0 (GTK+ 3.24.29; x86_64-w64-mingw32) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.122.247.231] X-ClientProxiedBy: lhreml745-chm.china.huawei.com (10.201.108.195) To lhreml710-chm.china.huawei.com (10.201.108.61) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-cxl@vger.kernel.org On Wed, 23 Mar 2022 18:11:20 -0700 alison.schofield@intel.com wrote: > From: Alison Schofield > > In preparation for moving the construction of a mailbox command > to the validation path, extract the work into a helper function. > > Signed-off-by: Alison Schofield Some suggestions for possible improvements to code organization now possible because everything is in one place. Otherwise looks good to me. Jonathan > --- > drivers/cxl/core/mbox.c | 60 +++++++++++++++++++++++++---------------- > 1 file changed, 37 insertions(+), 23 deletions(-) > > diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c > index 28131c6f7fcf..d4233cfb2f99 100644 > --- a/drivers/cxl/core/mbox.c > +++ b/drivers/cxl/core/mbox.c > @@ -207,6 +207,38 @@ static bool cxl_mem_raw_command_allowed(u16 opcode) > return true; > } > > +static int cxl_to_mbox_cmd(struct cxl_dev_state *cxlds, > + struct cxl_mbox_cmd *mbox, u16 opcode, > + size_t in_size, size_t out_size, u64 in_payload) > +{ > + *mbox = (struct cxl_mbox_cmd) { > + .opcode = opcode, > + .size_in = in_size, > + .size_out = out_size, Given we are going to possibly override this later, my inclination would be to not set it here and instead do if (out_size < 0) mbox->size_out = cxlds->payload_size else mbox->size_out = out_size; or mbox->size_out = out_size < 0 ? cxlds->payload_size : out_size; > + }; > + > + if (!in_size) > + goto size_out; > + > + mbox->payload_in = vmemdup_user(u64_to_user_ptr(in_payload), in_size); > + if (!mbox->payload_in) > + return PTR_ERR(mbox->payload_in); > + > +size_out: Why format this like this? Using a goto to skip a couple of lines of code is a bit ugly. if (in_size) { mbox->payload_in = vmemdup_user(u64_to_user_ptr(in_payload), in_size); if (!mbox->payload_in) return PTR_ERR(mbox->payload_in); } etc > + /* Prepare to handle a full payload for variable sized output */ > + if (out_size < 0) > + mbox->size_out = cxlds->payload_size; > + > + if (mbox->size_out) { > + mbox->payload_out = kvzalloc(mbox->size_out, GFP_KERNEL); > + if (!mbox->payload_out) { > + kvfree(mbox->payload_in); > + return -ENOMEM; > + } > + } > + return 0; > +} > + > static int cxl_to_mem_cmd_raw(struct cxl_dev_state *cxlds, > const struct cxl_send_command *send_cmd, > struct cxl_mem_command *mem_cmd) > @@ -397,27 +429,13 @@ static int handle_mailbox_cmd_from_user(struct cxl_dev_state *cxlds, > s32 *size_out, u32 *retval) > { > struct device *dev = cxlds->dev; > - struct cxl_mbox_cmd mbox_cmd = { > - .opcode = cmd->opcode, > - .size_in = cmd->info.size_in, > - .size_out = cmd->info.size_out, > - }; > + struct cxl_mbox_cmd mbox_cmd; > int rc; > > - if (cmd->info.size_out) { > - mbox_cmd.payload_out = kvzalloc(cmd->info.size_out, GFP_KERNEL); > - if (!mbox_cmd.payload_out) > - return -ENOMEM; > - } > - > - if (cmd->info.size_in) { > - mbox_cmd.payload_in = vmemdup_user(u64_to_user_ptr(in_payload), > - cmd->info.size_in); > - if (IS_ERR(mbox_cmd.payload_in)) { > - kvfree(mbox_cmd.payload_out); > - return PTR_ERR(mbox_cmd.payload_in); > - } > - } > + rc = cxl_to_mbox_cmd(cxlds, &mbox_cmd, cmd->opcode, cmd->info.size_in, > + cmd->info.size_out, in_payload); > + if (rc) > + return rc; > > dev_dbg(dev, > "Submitting %s command for user\n" > @@ -471,10 +489,6 @@ int cxl_send_cmd(struct cxl_memdev *cxlmd, struct cxl_send_command __user *s) > if (rc) > return rc; > > - /* Prepare to handle a full payload for variable sized output */ > - if (c.info.size_out < 0) > - c.info.size_out = cxlds->payload_size; > - > rc = handle_mailbox_cmd_from_user(cxlds, &c, send.in.payload, > send.out.payload, &send.out.size, > &send.retval);