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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 80391C43142 for ; Sun, 24 Jun 2018 02:16:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3096A24D83 for ; Sun, 24 Jun 2018 02:16:19 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3096A24D83 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=talpey.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751597AbeFXCQR (ORCPT ); Sat, 23 Jun 2018 22:16:17 -0400 Received: from p3plsmtpa12-06.prod.phx3.secureserver.net ([68.178.252.235]:33661 "EHLO p3plsmtpa12-06.prod.phx3.secureserver.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751606AbeFXCQP (ORCPT ); Sat, 23 Jun 2018 22:16:15 -0400 Received: from [192.168.0.67] ([24.218.182.144]) by :SMTPAUTH: with ESMTPSA id WuZafFgSeVxevWuZafzrMs; Sat, 23 Jun 2018 19:16:15 -0700 Subject: Re: [Patch v2 09/15] CIFS: SMBD: Support page offset in RDMA recv To: longli@microsoft.com, Steve French , linux-cifs@vger.kernel.org, samba-technical@lists.samba.org, linux-kernel@vger.kernel.org, linux-rdma@vger.kernel.org References: <20180530194807.31657-1-longli@linuxonhyperv.com> <20180530194807.31657-10-longli@linuxonhyperv.com> From: Tom Talpey Message-ID: <1e6b7cb0-98e8-d1fd-cb59-d3344fc70b19@talpey.com> Date: Sat, 23 Jun 2018 22:16:15 -0400 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.8.0 MIME-Version: 1.0 In-Reply-To: <20180530194807.31657-10-longli@linuxonhyperv.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-CMAE-Envelope: MS4wfJjtfXTqM0909Ps86VAfYG2L4yrmvSSS/GiveIofQEJI0tq02EXdIZGoO0uOOqz2YCgnA9h8UFwRXKrOvxguS3CYpjmUr/6BUPeym3zAMK3wkTWoImgH x3vsbz+vTGVW+oYHFZndykq/7NPdIWrV3Zqac8fyCU6o4OPeiHcF12OwUObFMbprQ2uVbMprvfl6mNIKceMW9WdKNVSk+Q4BsfW9Aq33lt+ZWH9deJCullho iYbjwhBU6KOSI/ZS/AkKeWbqf/H92mAB/VuioVmr0sYZpsgc1Sxq1kn9aWESDQ8kdnbk8cTNZt8ltYsBMDTye0aRYL3P7dxIArmRThYfdyzwxMD80MwcK0aw F2KkygVt Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 5/30/2018 3:48 PM, Long Li wrote: > From: Long Li > > RDMA recv function needs to place data to the correct place starting at > page offset. > > Signed-off-by: Long Li > --- > fs/cifs/smbdirect.c | 18 +++++++++++------- > 1 file changed, 11 insertions(+), 7 deletions(-) > > diff --git a/fs/cifs/smbdirect.c b/fs/cifs/smbdirect.c > index 6141e3c..ba53c52 100644 > --- a/fs/cifs/smbdirect.c > +++ b/fs/cifs/smbdirect.c > @@ -2004,10 +2004,12 @@ static int smbd_recv_buf(struct smbd_connection *info, char *buf, > * return value: actual data read > */ > static int smbd_recv_page(struct smbd_connection *info, > - struct page *page, unsigned int to_read) > + struct page *page, unsigned int page_offset, > + unsigned int to_read) > { > int ret; > char *to_address; > + void *page_address; > > /* make sure we have the page ready for read */ > ret = wait_event_interruptible( > @@ -2015,16 +2017,17 @@ static int smbd_recv_page(struct smbd_connection *info, > info->reassembly_data_length >= to_read || > info->transport_status != SMBD_CONNECTED); > if (ret) > - return 0; > + return ret; > > /* now we can read from reassembly queue and not sleep */ > - to_address = kmap_atomic(page); > + page_address = kmap_atomic(page); > + to_address = (char *) page_address + page_offset; > > log_read(INFO, "reading from page=%p address=%p to_read=%d\n", > page, to_address, to_read); > > ret = smbd_recv_buf(info, to_address, to_read); > - kunmap_atomic(to_address); > + kunmap_atomic(page_address); Is "page" truly not mapped? This kmap/kunmap for each received 4KB is very expensive. Is there not a way to keep a kva for the reassembly queue segments? > > return ret; > } > @@ -2038,7 +2041,7 @@ int smbd_recv(struct smbd_connection *info, struct msghdr *msg) > { > char *buf; > struct page *page; > - unsigned int to_read; > + unsigned int to_read, page_offset; > int rc; > > info->smbd_recv_pending++; > @@ -2052,15 +2055,16 @@ int smbd_recv(struct smbd_connection *info, struct msghdr *msg) > > case READ | ITER_BVEC: > page = msg->msg_iter.bvec->bv_page; > + page_offset = msg->msg_iter.bvec->bv_offset; > to_read = msg->msg_iter.bvec->bv_len; > - rc = smbd_recv_page(info, page, to_read); > + rc = smbd_recv_page(info, page, page_offset, to_read); > break; > > default: > /* It's a bug in upper layer to get there */ > cifs_dbg(VFS, "CIFS: invalid msg type %d\n", > msg->msg_iter.type); > - rc = -EIO; > + rc = -EINVAL; > } > > info->smbd_recv_pending--; >