From patchwork Tue Nov 8 05:05:13 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jonathan Lemon X-Patchwork-Id: 13035887 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 5E132C43217 for ; Tue, 8 Nov 2022 05:05:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229747AbiKHFFg convert rfc822-to-8bit (ORCPT ); Tue, 8 Nov 2022 00:05:36 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38792 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230246AbiKHFFe (ORCPT ); Tue, 8 Nov 2022 00:05:34 -0500 Received: from mx0a-00082601.pphosted.com (mx0a-00082601.pphosted.com [67.231.145.42]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B4002AE44 for ; Mon, 7 Nov 2022 21:05:33 -0800 (PST) Received: from pps.filterd (m0148461.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 2A80Utv8007222 for ; Mon, 7 Nov 2022 21:05:33 -0800 Received: from mail.thefacebook.com ([163.114.132.120]) by mx0a-00082601.pphosted.com (PPS) with ESMTPS id 3kqcmqse5s-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Mon, 07 Nov 2022 21:05:33 -0800 Received: from twshared5476.02.ash7.facebook.com (2620:10d:c085:108::4) by mail.thefacebook.com (2620:10d:c085:11d::7) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Mon, 7 Nov 2022 21:05:32 -0800 Received: by devvm2494.atn0.facebook.com (Postfix, from userid 172786) id 0CB6C23B26015; Mon, 7 Nov 2022 21:05:22 -0800 (PST) From: Jonathan Lemon To: CC: Subject: [PATCH v1 07/15] io_uring: Allocate zctap device buffers and dma map them. Date: Mon, 7 Nov 2022 21:05:13 -0800 Message-ID: <20221108050521.3198458-8-jonathan.lemon@gmail.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20221108050521.3198458-1-jonathan.lemon@gmail.com> References: <20221108050521.3198458-1-jonathan.lemon@gmail.com> MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-GUID: an758WKV419bhmqoSaFd1I5IpsJtwp3C X-Proofpoint-ORIG-GUID: an758WKV419bhmqoSaFd1I5IpsJtwp3C X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.219,Aquarius:18.0.895,Hydra:6.0.545,FMLib:17.11.122.1 definitions=2022-11-07_11,2022-11-07_02,2022-06-22_01 Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org The goal is to register a memory region with the device, and later specify the desired packet buffer size. The code currently assumes a page size. Create the desired number of zctap buffers and DMA map them to the target device, recording the dma address for later use. Hold a page reference while the page is dma mapped. Change the freelist from an array of page pointers to an index into the device buffer list. Signed-off-by: Jonathan Lemon --- io_uring/zctap.c | 78 ++++++++++++++++++++++++++++++++++++++---------- 1 file changed, 63 insertions(+), 15 deletions(-) diff --git a/io_uring/zctap.c b/io_uring/zctap.c index 69a04de87f8f..fe4bb3781636 100644 --- a/io_uring/zctap.c +++ b/io_uring/zctap.c @@ -18,11 +18,14 @@ #define NR_ZCTAP_IFQS 1 struct ifq_region { + struct io_zctap_ifq *ifq; /* only for delayed_work */ struct io_mapped_ubuf *imu; int free_count; int nr_pages; u16 id; - struct page *freelist[]; + + struct io_zctap_buf *buf; + u16 freelist[]; }; typedef int (*bpf_op_t)(struct net_device *dev, struct netdev_bpf *bpf); @@ -60,49 +63,85 @@ bool io_zctap_put_page(struct io_zctap_ifq *ifq, struct page *page) } EXPORT_SYMBOL(io_zctap_put_page); +static inline struct device * +netdev2device(struct net_device *dev) +{ + return dev->dev.parent; /* from SET_NETDEV_DEV() */ +} + static void io_remove_ifq_region(struct ifq_region *ifr) { - struct io_mapped_ubuf *imu; - struct page *page; + struct device *device = netdev2device(ifr->ifq->dev); + struct io_zctap_buf *buf; int i; - imu = ifr->imu; for (i = 0; i < ifr->nr_pages; i++) { - page = imu->bvec[i].bv_page; - - ClearPagePrivate(page); - set_page_private(page, 0); + buf = &ifr->buf[i]; + set_page_private(buf->page, 0); + ClearPagePrivate(buf->page); + dma_unmap_page_attrs(device, buf->dma, PAGE_SIZE, + DMA_BIDIRECTIONAL, + DMA_ATTR_SKIP_CPU_SYNC); + put_page(buf->page); } + kvfree(ifr->buf); kvfree(ifr); } -static int io_zctap_map_region(struct ifq_region *ifr) +static int io_zctap_map_region(struct ifq_region *ifr, struct device *device) { struct io_mapped_ubuf *imu; + struct io_zctap_buf *buf; struct page *page; + dma_addr_t addr; + int i, err; u64 info; - int i; imu = ifr->imu; for (i = 0; i < ifr->nr_pages; i++) { page = imu->bvec[i].bv_page; - if (PagePrivate(page)) + + if (PagePrivate(page)) { + err = -EEXIST; goto out; + } + SetPagePrivate(page); info = zctap_mk_page_info(ifr->id, i); zctap_set_page_info(page, info); - ifr->freelist[i] = page; + + buf = &ifr->buf[i]; + addr = dma_map_page_attrs(device, page, 0, PAGE_SIZE, + DMA_BIDIRECTIONAL, + DMA_ATTR_SKIP_CPU_SYNC); + if (dma_mapping_error(device, addr)) { + set_page_private(page, 0); + ClearPagePrivate(page); + err = -ENOMEM; + goto out; + } + buf->dma = addr; + buf->page = page; + atomic_set(&buf->refcount, 0); + get_page(page); + + ifr->freelist[i] = i; } return 0; out: while (i--) { page = imu->bvec[i].bv_page; - ClearPagePrivate(page); set_page_private(page, 0); + ClearPagePrivate(page); + buf = &ifr->buf[i]; + dma_unmap_page_attrs(device, buf->dma, PAGE_SIZE, + DMA_BIDIRECTIONAL, + DMA_ATTR_SKIP_CPU_SYNC); + put_page(page); } - return -EEXIST; + return err; } int io_provide_ifq_region(struct io_zctap_ifq *ifq, u16 id) @@ -131,13 +170,22 @@ int io_provide_ifq_region(struct io_zctap_ifq *ifq, u16 id) if (!ifr) return -ENOMEM; + ifr->buf = kvmalloc_array(nr_pages, sizeof(*ifr->buf), GFP_KERNEL); + if (!ifr->buf) { + kvfree(ifr); + return -ENOMEM; + } + ifr->nr_pages = nr_pages; ifr->imu = imu; ifr->free_count = nr_pages; ifr->id = id; - err = io_zctap_map_region(ifr); + ifr->ifq = ifq; /* XXX */ + + err = io_zctap_map_region(ifr, netdev2device(ifq->dev)); if (err) { + kvfree(ifr->buf); kvfree(ifr); return err; }