From nobody Mon Feb 9 13:00:32 2026 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 BE372EB64D9 for ; Mon, 10 Jul 2023 22:34:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230374AbjGJWeH (ORCPT ); Mon, 10 Jul 2023 18:34:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58878 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230344AbjGJWeA (ORCPT ); Mon, 10 Jul 2023 18:34:00 -0400 Received: from mail-yw1-x1149.google.com (mail-yw1-x1149.google.com [IPv6:2607:f8b0:4864:20::1149]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 97746E55 for ; Mon, 10 Jul 2023 15:33:53 -0700 (PDT) Received: by mail-yw1-x1149.google.com with SMTP id 00721157ae682-57059e6f9c7so73873987b3.0 for ; Mon, 10 Jul 2023 15:33:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1689028432; x=1691620432; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=ZtAFtzT26HwoXDlgQMNRwGQzav+ArXt3GcR/tyBO9gA=; b=HkBlwsebRlph1pf39ww19ir3TXRKAaMo7qsHRnHvMwd7eaBtsd+aEsyn2PFrjYVPN/ Q1m2zbfqNxMH7b2QmwqEmx7Hw8+0VDdPsjPbv5ClyeuSbRANbqwhxJwBlxKfNPSzGspo 7yQorKtO9RR3lY8Caocl1cEReHVAh3gKZjRNe8K/5mwfYof1P1cHyHw8LwIbAtpadOQi xt/cqEvGCmmTBBOu377T/OItahks2lVVcdnKMKB3565gPdYG/TvH20z3G9f0jRiObQC7 /Ikbp8b7IOidW9ZdGHVTIfQ7XQf/3jcuOVmetsVhHpuKf5wo9wt+kW67ruZRHH/8+c9U xfJg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1689028432; x=1691620432; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=ZtAFtzT26HwoXDlgQMNRwGQzav+ArXt3GcR/tyBO9gA=; b=D56Xum9Fe7I35d1nknbKkP2EmR3UgB3h82bbHJblU/zjOJxdwUL5WpMKn3iASlq4ZX nv3E+chyWlvE8VMNKEI6n+QtEyTzBsSWBUPg2SHMRYLrIrwxpcQfUzCXmiPI9sr7hfn6 2OeANfo1wYiT/XSOhGcRUfd+zBPXsqucadVddXnfZqF4+LBhxnhUcasLbom2JKJTGsAc F9WFYkI9dFivz3qCJTDnDb53a980LADCvNdpdfexkfJe2DaFva+WrLzJ0Ryi4XVCEPSd 9jO7fTVIy59gq3am4krgTPFaHgG0Zl11kW5kWWGp4VUQ86Jj3epjBr1tjeS7dnQVsSBT WFRA== X-Gm-Message-State: ABy/qLa4wHonWGXvMhEszmdR2+89flQ7Dt7oRsy9j3+FQgI/78GNTcpb +JnKiG6cQ4tptrf0UyGKsRsGxmlAr2itaVjX1zo7yIjRfJF2ovzMK1x2sb1iHOOfju7B7f9WaY2 Hfyb3qVWcW/yq6HjT1w/OaaGu69f9iXiKthVYjivMhzx+7qOqjJQsuTtf8gk6c3kARlaX8VIu79 g30G/lE3g= X-Google-Smtp-Source: APBJJlHZU5kmoFW1exgCNXZVHrLAP9FADaXQZjpO/QBcTqC0+9vh1t2Y55mCZ3uaTrm2ya/0CivoRDUtK7ota9l6xA== X-Received: from almasrymina.svl.corp.google.com ([2620:15c:2c4:200:4c0f:bfb6:9942:8c53]) (user=almasrymina job=sendgmr) by 2002:a81:7e0c:0:b0:56c:e9fe:3cb4 with SMTP id o12-20020a817e0c000000b0056ce9fe3cb4mr204351ywn.1.1689028432231; Mon, 10 Jul 2023 15:33:52 -0700 (PDT) Date: Mon, 10 Jul 2023 15:32:54 -0700 In-Reply-To: <20230710223304.1174642-1-almasrymina@google.com> Mime-Version: 1.0 References: <20230710223304.1174642-1-almasrymina@google.com> X-Mailer: git-send-email 2.41.0.390.g38632f3daf-goog Message-ID: <20230710223304.1174642-4-almasrymina@google.com> Subject: [RFC PATCH 03/10] dma-buf: add support for NET_TX pages From: Mina Almasry To: linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, netdev@vger.kernel.org, linux-arch@vger.kernel.org, linux-kselftest@vger.kernel.org Cc: Mina Almasry , Sumit Semwal , "=?UTF-8?q?Christian=20K=C3=B6nig?=" , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Jesper Dangaard Brouer , Ilias Apalodimas , Arnd Bergmann , David Ahern , Willem de Bruijn , Shuah Khan , jgg@ziepe.ca Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Used the paged attachment mappings support to create NET_TX pages. NET_TX pages can be used in the networking transmit path: 1. Create an iov_iter & bio_vec entries to represent this dmabuf. 2. Initialize the bio_vec with the backing dmabuf pages. Signed-off-by: Mina Almasry --- drivers/dma-buf/dma-buf.c | 47 ++++++++++++++++++++++++++++++++++++ include/linux/dma-buf.h | 7 ++++++ include/uapi/linux/dma-buf.h | 1 + 3 files changed, 55 insertions(+) diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index acb86bf406f4..3ca71297b9b4 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -1683,6 +1683,7 @@ static void dma_buf_pages_destroy(struct percpu_ref *= ref) } =20 const struct dma_buf_pages_type_ops net_rx_ops; +const struct dma_buf_pages_type_ops net_tx_ops; =20 static long dma_buf_create_pages(struct file *file, struct dma_buf_create_pages_info *create_info) @@ -1799,6 +1800,9 @@ static long dma_buf_create_pages(struct file *file, case DMA_BUF_PAGES_NET_RX: priv->type_ops =3D &net_rx_ops; break; + case DMA_BUF_PAGES_NET_TX: + priv->type_ops =3D &net_tx_ops; + break; default: err =3D -EINVAL; goto out_put_new_file; @@ -2140,3 +2144,46 @@ struct page *dma_buf_pages_net_rx_alloc(struct dma_b= uf_pages *priv) percpu_ref_get(&priv->pgmap.ref); return pg; } + +/******************************** + * dma_buf_pages_net_tx * + ********************************/ + +static void dma_buf_pages_net_tx_release(struct dma_buf_pages *priv, + struct file *file) +{ + int i; + for (i =3D 0; i < priv->num_pages; i++) + put_page(&priv->pages[i]); +} + +static int dma_buf_pages_net_tx_init(struct dma_buf_pages *priv, + struct file *file) +{ + int i; + priv->net_tx.tx_bv =3D kvmalloc_array(priv->num_pages, + sizeof(struct bio_vec), GFP_KERNEL); + if (!priv->net_tx.tx_bv) + return -ENOMEM; + + for (i =3D 0; i < priv->num_pages; i++) { + priv->net_tx.tx_bv[i].bv_page =3D &priv->pages[i]; + priv->net_tx.tx_bv[i].bv_offset =3D 0; + priv->net_tx.tx_bv[i].bv_len =3D PAGE_SIZE; + } + percpu_ref_get_many(&priv->pgmap.ref, priv->num_pages); + iov_iter_bvec(&priv->net_tx.iter, WRITE, priv->net_tx.tx_bv, + priv->num_pages, priv->dmabuf->size); + return 0; +} + +static void dma_buf_pages_net_tx_free(struct dma_buf_pages *priv) +{ + kvfree(priv->net_tx.tx_bv); +} + +const struct dma_buf_pages_type_ops net_tx_ops =3D { + .dma_buf_pages_init =3D dma_buf_pages_net_tx_init, + .dma_buf_pages_release =3D dma_buf_pages_net_tx_release, + .dma_buf_pages_destroy =3D dma_buf_pages_net_tx_free, +}; diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h index e8e66d6407d0..93228a2fec47 100644 --- a/include/linux/dma-buf.h +++ b/include/linux/dma-buf.h @@ -22,6 +22,7 @@ #include #include #include +#include #include #include #include @@ -555,6 +556,11 @@ struct dma_buf_pages_type_ops { struct page *page); }; =20 +struct dma_buf_pages_net_tx { + struct iov_iter iter; + struct bio_vec *tx_bv; +}; + struct dma_buf_pages_net_rx { struct gen_pool *page_pool; struct xarray bound_rxq_list; @@ -579,6 +585,7 @@ struct dma_buf_pages { =20 union { struct dma_buf_pages_net_rx net_rx; + struct dma_buf_pages_net_tx net_tx; }; }; =20 diff --git a/include/uapi/linux/dma-buf.h b/include/uapi/linux/dma-buf.h index b392cef9d3c6..546f211a7556 100644 --- a/include/uapi/linux/dma-buf.h +++ b/include/uapi/linux/dma-buf.h @@ -187,6 +187,7 @@ struct dma_buf_create_pages_info { }; =20 #define DMA_BUF_PAGES_NET_RX (1 << 0) +#define DMA_BUF_PAGES_NET_TX (2 << 0) =20 #define DMA_BUF_CREATE_PAGES _IOW(DMA_BUF_BASE, 4, struct dma_buf_create_p= ages_info) =20 --=20 2.41.0.390.g38632f3daf-goog