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 76996C433FE for ; Tue, 8 Nov 2022 05:05:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232641AbiKHFFr convert rfc822-to-8bit (ORCPT ); Tue, 8 Nov 2022 00:05:47 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39050 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230246AbiKHFFm (ORCPT ); Tue, 8 Nov 2022 00:05:42 -0500 Received: from mx0b-00082601.pphosted.com (mx0b-00082601.pphosted.com [67.231.153.30]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DB1F2186FF for ; Mon, 7 Nov 2022 21:05:39 -0800 (PST) Received: from pps.filterd (m0109332.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 2A7LKnx2022573 for ; Mon, 7 Nov 2022 21:05:39 -0800 Received: from maileast.thefacebook.com ([163.114.130.8]) by mx0a-00082601.pphosted.com (PPS) with ESMTPS id 3kq6kk4yf4-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Mon, 07 Nov 2022 21:05:39 -0800 Received: from twshared2001.03.ash8.facebook.com (2620:10d:c0a8:1b::d) by mail.thefacebook.com (2620:10d:c0a8:83::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 21:05:37 -0800 Received: by devvm2494.atn0.facebook.com (Postfix, from userid 172786) id 21FDA23B2601B; Mon, 7 Nov 2022 21:05:22 -0800 (PST) From: Jonathan Lemon To: CC: Subject: [PATCH v1 10/15] io_uring: Allocate a uarg for use by the ifq RX Date: Mon, 7 Nov 2022 21:05:16 -0800 Message-ID: <20221108050521.3198458-11-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 Content-Transfer-Encoding: 8BIT X-FB-Internal: Safe Content-Type: text/plain X-Proofpoint-ORIG-GUID: H2FP-aF33JfnBK3GNiiVm6LkVdqEKc_J X-Proofpoint-GUID: H2FP-aF33JfnBK3GNiiVm6LkVdqEKc_J 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 Create a static uarg which is attached to zerocopy RX buffers, and add a callback to handle freeing the skb. As the skb is marked as zerocopy, it bypasses the default network skb fragment destructor and uses our callback. This handles our buffer refcounts, and releases the ZC buffer back to the freelist. Add the put_page() implementations, which release the fragments. This may also be called by drivers during cleanup. Signed-off-by: Jonathan Lemon --- io_uring/zctap.c | 64 ++++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 56 insertions(+), 8 deletions(-) diff --git a/io_uring/zctap.c b/io_uring/zctap.c index 0da9e6510f36..10d74b8f7cef 100644 --- a/io_uring/zctap.c +++ b/io_uring/zctap.c @@ -30,6 +30,12 @@ struct ifq_region { u16 freelist[]; }; +/* XXX get around not having "struct ubuf_info" defined in io_uring_types.h */ +struct io_zctap_ifq_priv { + struct io_zctap_ifq ifq; + struct ubuf_info uarg; +}; + typedef int (*bpf_op_t)(struct net_device *dev, struct netdev_bpf *bpf); static void zctap_set_page_info(struct page *page, u64 info) @@ -52,6 +58,16 @@ static u16 zctap_page_id(const struct page *page) return zctap_page_info(page) & 0xffff; } +static bool zctap_page_magic(const struct page *page) +{ + return (zctap_page_info(page) >> 48) == 0xface; +} + +static bool zctap_page_ours(struct page *page) +{ + return PagePrivate(page) && zctap_page_magic(page); +} + /* driver bias cannot be larger than this */ #define IO_ZCTAP_UREF 0x10000 #define IO_ZCTAP_KREF_MASK (IO_ZCTAP_UREF - 1) @@ -70,7 +86,9 @@ static bool io_zctap_put_buf_uref(struct io_zctap_buf *buf) return atomic_sub_and_test(IO_ZCTAP_UREF, &buf->refcount); } -/* gets a user-supplied buffer from the fill queue */ +/* gets a user-supplied buffer from the fill queue + * note: may drain N entries, but still have no usable buffers + */ static struct io_zctap_buf *io_zctap_get_buffer(struct io_zctap_ifq *ifq, u16 *buf_pgid) { @@ -185,9 +203,19 @@ void io_zctap_put_buf_refs(struct io_zctap_ifq *ifq, struct io_zctap_buf *buf, } EXPORT_SYMBOL(io_zctap_put_buf_refs); +/* could be called by the stack as it drops/recycles the skbs */ bool io_zctap_put_page(struct io_zctap_ifq *ifq, struct page *page) { - return false; + struct ifq_region *ifr; + u16 pgid; + + if (!zctap_page_ours(page)) + return false; + + ifr = ifq->region; /* only one */ + pgid = zctap_page_id(page); + io_zctap_put_buf(ifq, &ifr->buf[pgid]); + return true; } EXPORT_SYMBOL(io_zctap_put_page); @@ -351,17 +379,35 @@ static int io_close_zctap_ifq(struct io_zctap_ifq *ifq, u16 queue_id) return __io_queue_mgmt(ifq->dev, NULL, queue_id); } +static void io_zctap_ifq_callback(struct sk_buff *skb, struct ubuf_info *uarg, + bool success) +{ + struct skb_shared_info *shinfo = skb_shinfo(skb); + struct io_zctap_ifq_priv *priv; + struct page *page; + int i; + + priv = container_of(uarg, struct io_zctap_ifq_priv, uarg); + + for (i = 0; i < shinfo->nr_frags; i++) { + page = skb_frag_page(&shinfo->frags[i]); + if (!io_zctap_put_page(&priv->ifq, page)) + __skb_frag_unref(&shinfo->frags[i], skb->pp_recycle); + } +} + static struct io_zctap_ifq *io_zctap_ifq_alloc(struct io_ring_ctx *ctx) { - struct io_zctap_ifq *ifq; + struct io_zctap_ifq_priv *priv; - ifq = kzalloc(sizeof(*ifq), GFP_KERNEL); - if (!ifq) + priv = kzalloc(sizeof(*priv), GFP_KERNEL); + if (!priv) return NULL; - ifq->ctx = ctx; - ifq->queue_id = -1; - return ifq; + priv->ifq.ctx = ctx; + priv->ifq.queue_id = -1; + priv->ifq.uarg = &priv->uarg; + return &priv->ifq; } static void io_zctap_ifq_free(struct io_zctap_ifq *ifq) @@ -399,6 +445,8 @@ int io_register_ifq(struct io_ring_ctx *ctx, return -ENOMEM; ifq->fill_bgid = req.fill_bgid; + ifq->uarg->callback = io_zctap_ifq_callback; + ifq->uarg->flags = SKBFL_ALL_ZEROCOPY | SKBFL_FIXED_FRAG; err = -ENODEV; ifq->dev = dev_get_by_index(&init_net, req.ifindex); -- 2.30.2