From nobody Tue Dec 16 22:18:30 2025 Received: from mail-yw1-f202.google.com (mail-yw1-f202.google.com [209.85.128.202]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5A7BB158D88 for ; Thu, 30 May 2024 20:16:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.202 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717100203; cv=none; b=q4c02/QQyO4v1eklLWoGNiu+dJqPSazLmueknbsWk1CdvZvZXJqnt5W2aQloxfEG6iN4kIsnIRnJ81x/7LIfW8xpU7xv8tXsgXk2wjYm9l/gudrv4IbJTvRjWI8V+tFwHeP1C4mkqcp6AIF6Vp/1O+AjSQB+gUU4/p97bZ0EWS4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717100203; c=relaxed/simple; bh=XUjFWGj6/WpAaFwycBfCrOCU9DlTes4t/F71EMkAvys=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=DG5uaujhoGS1KT5/dns2nA+M9iZHLD9RrgtochlrXRolMxJEtZvhfN0xwlngkb7jyH74Tv48jwSt5Dyc9yU3OqtVuucuAH8IPnGzQOrxrr9G2WM3ybh5qLAtQlYwnZYl3InXGT467Q5Cmmg4xKcuDxaI0uVn11R5ypJllFBdPOo= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--almasrymina.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=wmWVCbnc; arc=none smtp.client-ip=209.85.128.202 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--almasrymina.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="wmWVCbnc" Received: by mail-yw1-f202.google.com with SMTP id 00721157ae682-62a0841402aso4244347b3.2 for ; Thu, 30 May 2024 13:16:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1717100194; x=1717704994; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=+pHjSd+aIqRhv+ONO+ERZ6+Qj/zRJj03ekyM6mSPMSw=; b=wmWVCbncaCu6slFi8FMRu6CSf7OjTc3ooIJ6u4JTGz4uuB/5XYNqSY6kpiX8l+cv/a RS2YjRfGNDbTLe9RRtUCiqHDjyWFJFUOawr1MUergdAODIT43nGChItokZ8q50Jk6/Bc g37L5yJ+N/471zX6HSFi6EPPZZs+5rYS53yT0Uzo9kkSsDuoFEGRQVEDXSCceu4hUhpX qtmdfmxzzkXtIKxy4usn1YBEJ5T38MJlAUtAEB9OgYOrw2o9K3XwYhPfDs6DjcJhg/qy UHcWIB/w+OsfyMnFJxebDJ5OPdN02j1FqS9s9IbJPNejdtqzMo3m+4u0yKZ8QgDMaDQY ejcg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1717100194; x=1717704994; 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=+pHjSd+aIqRhv+ONO+ERZ6+Qj/zRJj03ekyM6mSPMSw=; b=JYgT59xzNwoBlCcItLuq2hRtMtlrG5qJK8Z5sZjlGMTRIXrajnrI3Ui88hMRRWzbli 6wHDHMTlmqBa57/dfvk3sbvDr8MNJ8pohnTIzLMi2RYSQwWYGe7j8nKls8YsF2UiEHPg nZ/CRjsrTnB1Gn/ipF0MJlhii0vMS3jym7qGdyR95qCv9M5Ty6WVoy6SPC/qq/L/4nrL lj1U5gZDmh/9ESbBuCL0OEYQ4l/+pGYxTPwENorLUEsA6PO8qFGmYn+Pf8pAoejwHmXj gtchXhowQRQYpKHS3gRkI1wmaBW8iTIr8OANhtyizmqQt8P0rZMRpaAnIX95/s/RW50Z dIdg== X-Forwarded-Encrypted: i=1; AJvYcCVFgsa784UrO7gkXhvtzAJ/4T3KvAfPN3lk73muxu6iuBnIN/BCLAgcOF2G61BZhG0AWscL/gV9Are+SERldL8qW2SrYDKZUM/FvanT X-Gm-Message-State: AOJu0YygMX2oCxGhX++OGBoTNOxpp6cRtIKH1lOi39emkQRwqL5ug9LX czBWpMFY4x3rS9CA5PEFllzeWfhvH5pSwZh4j8Zwa501ag4dFNJ+a329+Q/Uie460YlLucqUleT eep35q0aILnEPgApJlGsUcg== X-Google-Smtp-Source: AGHT+IGF2g6dxEX+gxT34hXKpp4EetOLAozp6L7SZwUKbjyW2NHWygGsIen9fVtJ1Yl28C4lRpzFPm38Ju/2eQQdZg== X-Received: from almasrymina.c.googlers.com ([fda3:e722:ac3:cc00:20:ed76:c0a8:4bc5]) (user=almasrymina job=sendgmr) by 2002:a05:690c:fd2:b0:627:7563:95b1 with SMTP id 00721157ae682-62c6bce7d09mr9510237b3.5.1717100193783; Thu, 30 May 2024 13:16:33 -0700 (PDT) Date: Thu, 30 May 2024 20:16:07 +0000 In-Reply-To: <20240530201616.1316526-1-almasrymina@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20240530201616.1316526-1-almasrymina@google.com> X-Mailer: git-send-email 2.45.1.288.g0e0cd299f1-goog Message-ID: <20240530201616.1316526-9-almasrymina@google.com> Subject: [PATCH net-next v10 08/14] memory-provider: dmabuf devmem memory provider From: Mina Almasry To: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-alpha@vger.kernel.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, sparclinux@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-arch@vger.kernel.org, bpf@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org Cc: Mina Almasry , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Donald Hunter , Jonathan Corbet , Richard Henderson , Ivan Kokshaysky , Matt Turner , Thomas Bogendoerfer , "James E.J. Bottomley" , Helge Deller , Andreas Larsson , Jesper Dangaard Brouer , Ilias Apalodimas , Steven Rostedt , Masami Hiramatsu , Mathieu Desnoyers , Arnd Bergmann , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Eduard Zingerman , Song Liu , Yonghong Song , John Fastabend , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Steffen Klassert , Herbert Xu , David Ahern , Willem de Bruijn , Shuah Khan , Sumit Semwal , "=?UTF-8?q?Christian=20K=C3=B6nig?=" , Pavel Begunkov , David Wei , Jason Gunthorpe , Yunsheng Lin , Shailend Chand , Harshitha Ramamurthy , Shakeel Butt , Jeroen de Borst , Praveen Kaligineedi , Willem de Bruijn , Kaiyuan Zhang Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Implement a memory provider that allocates dmabuf devmem in the form of net_iov. The provider receives a reference to the struct netdev_dmabuf_binding via the pool->mp_priv pointer. The driver needs to set this pointer for the provider in the net_iov. The provider obtains a reference on the netdev_dmabuf_binding which guarantees the binding and the underlying mapping remains alive until the provider is destroyed. Usage of PP_FLAG_DMA_MAP is required for this memory provide such that the page_pool can provide the driver with the dma-addrs of the devmem. Support for PP_FLAG_DMA_SYNC_DEV is omitted for simplicity & p.order !=3D 0. Signed-off-by: Willem de Bruijn Signed-off-by: Kaiyuan Zhang Signed-off-by: Mina Almasry --- v8: - Use skb_frag_size instead of frag->bv_len to fix patch-by-patch build error v6: - refactor new memory provider functions into net/core/devmem.c (Pavel) v2: - Disable devmem for p.order !=3D 0 v1: - static_branch check in page_is_page_pool_iov() (Willem & Paolo). - PP_DEVMEM -> PP_IOV (David). - Require PP_FLAG_DMA_MAP (Jakub). --- include/net/netmem.h | 15 ++++++ include/net/page_pool/helpers.h | 22 +++++++++ include/net/page_pool/types.h | 2 + net/core/devmem.c | 83 +++++++++++++++++++++++++++++++++ net/core/page_pool.c | 38 +++++++-------- 5 files changed, 138 insertions(+), 22 deletions(-) diff --git a/include/net/netmem.h b/include/net/netmem.h index 35ad237fdf29e..7c28d6fac6242 100644 --- a/include/net/netmem.h +++ b/include/net/netmem.h @@ -100,6 +100,21 @@ static inline struct page *netmem_to_page(netmem_ref n= etmem) return (__force struct page *)netmem; } =20 +static inline struct net_iov *netmem_to_net_iov(netmem_ref netmem) +{ + if (netmem_is_net_iov(netmem)) + return (struct net_iov *)((__force unsigned long)netmem & + ~NET_IOV); + + DEBUG_NET_WARN_ON_ONCE(true); + return NULL; +} + +static inline netmem_ref net_iov_to_netmem(struct net_iov *niov) +{ + return (__force netmem_ref)((unsigned long)niov | NET_IOV); +} + static inline netmem_ref page_to_netmem(struct page *page) { return (__force netmem_ref)page; diff --git a/include/net/page_pool/helpers.h b/include/net/page_pool/helper= s.h index 1770c7be24afc..731f2d1e1ee10 100644 --- a/include/net/page_pool/helpers.h +++ b/include/net/page_pool/helpers.h @@ -477,4 +477,26 @@ static inline void page_pool_nid_changed(struct page_p= ool *pool, int new_nid) page_pool_update_nid(pool, new_nid); } =20 +static inline void page_pool_set_pp_info(struct page_pool *pool, + netmem_ref netmem) +{ + netmem_set_pp(netmem, pool); + netmem_or_pp_magic(netmem, PP_SIGNATURE); + + /* Ensuring all pages have been split into one fragment initially: + * page_pool_set_pp_info() is only called once for every page when it + * is allocated from the page allocator and page_pool_fragment_page() + * is dirtying the same cache line as the page->pp_magic above, so + * the overhead is negligible. + */ + page_pool_fragment_netmem(netmem, 1); + if (pool->has_init_callback) + pool->slow.init_callback(netmem, pool->slow.init_arg); +} + +static inline void page_pool_clear_pp_info(netmem_ref netmem) +{ + netmem_clear_pp_magic(netmem); + netmem_set_pp(netmem, NULL); +} #endif /* _NET_PAGE_POOL_HELPERS_H */ diff --git a/include/net/page_pool/types.h b/include/net/page_pool/types.h index edc3066e1ea56..87a7799460267 100644 --- a/include/net/page_pool/types.h +++ b/include/net/page_pool/types.h @@ -142,6 +142,8 @@ struct pp_memory_provider_params { void *mp_priv; }; =20 +extern const struct memory_provider_ops dmabuf_devmem_ops; + struct page_pool { struct page_pool_params_fast p; =20 diff --git a/net/core/devmem.c b/net/core/devmem.c index fe9865699abb1..e591449a3cf1b 100644 --- a/net/core/devmem.c +++ b/net/core/devmem.c @@ -163,6 +163,7 @@ int net_devmem_bind_dmabuf_to_queue(struct net_device *= dev, u32 rxq_idx, * the driver may read this config while it's creating its * rx-queues. * WRITE_ONCE() here to match the READ_ONCE() in the driver. */ + WRITE_ONCE(rxq->mp_params.mp_ops, &dmabuf_devmem_ops); WRITE_ONCE(rxq->mp_params.mp_priv, binding); =20 err =3D netdev_rx_queue_restart(dev, rxq_idx); @@ -298,4 +299,86 @@ int net_devmem_bind_dmabuf(struct net_device *dev, uns= igned int dmabuf_fd, dma_buf_put(dmabuf); return err; } + +/*** "Dmabuf devmem memory provider" ***/ + +static int mp_dmabuf_devmem_init(struct page_pool *pool) +{ + struct net_devmem_dmabuf_binding *binding =3D pool->mp_priv; + + if (!binding) + return -EINVAL; + + if (!pool->dma_map) + return -EOPNOTSUPP; + + if (pool->dma_sync) + return -EOPNOTSUPP; + + if (pool->p.order !=3D 0) + return -E2BIG; + + net_devmem_dmabuf_binding_get(binding); + return 0; +} + +static netmem_ref mp_dmabuf_devmem_alloc_netmems(struct page_pool *pool, + gfp_t gfp) +{ + struct net_devmem_dmabuf_binding *binding =3D pool->mp_priv; + netmem_ref netmem; + struct net_iov *niov; + dma_addr_t dma_addr; + + niov =3D net_devmem_alloc_dmabuf(binding); + if (!niov) + return 0; + + dma_addr =3D net_devmem_get_dma_addr(niov); + + netmem =3D net_iov_to_netmem(niov); + + page_pool_set_pp_info(pool, netmem); + + if (page_pool_set_dma_addr_netmem(netmem, dma_addr)) + goto err_free; + + pool->pages_state_hold_cnt++; + trace_page_pool_state_hold(pool, netmem, pool->pages_state_hold_cnt); + return netmem; + +err_free: + net_devmem_free_dmabuf(niov); + return 0; +} + +static void mp_dmabuf_devmem_destroy(struct page_pool *pool) +{ + struct net_devmem_dmabuf_binding *binding =3D pool->mp_priv; + + net_devmem_dmabuf_binding_put(binding); +} + +static bool mp_dmabuf_devmem_release_page(struct page_pool *pool, + netmem_ref netmem) +{ + WARN_ON_ONCE(!netmem_is_net_iov(netmem)); + WARN_ON_ONCE(atomic_long_read(netmem_get_pp_ref_count_ref(netmem)) !=3D + 1); + + page_pool_clear_pp_info(netmem); + + net_devmem_free_dmabuf(netmem_to_net_iov(netmem)); + + /* We don't want the page pool put_page()ing our net_iovs. */ + return false; +} + +const struct memory_provider_ops dmabuf_devmem_ops =3D { + .init =3D mp_dmabuf_devmem_init, + .destroy =3D mp_dmabuf_devmem_destroy, + .alloc_netmems =3D mp_dmabuf_devmem_alloc_netmems, + .release_page =3D mp_dmabuf_devmem_release_page, +}; +EXPORT_SYMBOL(dmabuf_devmem_ops); #endif diff --git a/net/core/page_pool.c b/net/core/page_pool.c index fa2a1f7ba0067..b625791a0fe77 100644 --- a/net/core/page_pool.c +++ b/net/core/page_pool.c @@ -13,6 +13,7 @@ =20 #include #include +#include =20 #include #include @@ -21,12 +22,15 @@ #include #include #include +#include +#include =20 #include =20 #include "page_pool_priv.h" =20 DEFINE_STATIC_KEY_FALSE(page_pool_mem_providers); +EXPORT_SYMBOL(page_pool_mem_providers); =20 #define DEFER_TIME (msecs_to_jiffies(1000)) #define DEFER_WARN_INTERVAL (60 * HZ) @@ -187,7 +191,9 @@ static int page_pool_init(struct page_pool *pool, const struct page_pool_params *params, int cpuid) { + const struct memory_provider_ops *mp_ops =3D NULL; unsigned int ring_qsize =3D 1024; /* Default */ + void *mp_priv =3D NULL; int err; =20 page_pool_struct_check(); @@ -270,6 +276,16 @@ static int page_pool_init(struct page_pool *pool, if (pool->dma_map) get_device(pool->p.dev); =20 + if (pool->p.queue) { + mp_ops =3D READ_ONCE(pool->p.queue->mp_params.mp_ops); + mp_priv =3D READ_ONCE(pool->p.queue->mp_params.mp_priv); + } + + if (mp_ops && mp_priv) { + pool->mp_ops =3D mp_ops; + pool->mp_priv =3D mp_priv; + } + if (pool->mp_ops) { err =3D pool->mp_ops->init(pool); if (err) { @@ -469,28 +485,6 @@ static bool page_pool_dma_map(struct page_pool *pool, = netmem_ref netmem) return false; } =20 -static void page_pool_set_pp_info(struct page_pool *pool, netmem_ref netme= m) -{ - netmem_set_pp(netmem, pool); - netmem_or_pp_magic(netmem, PP_SIGNATURE); - - /* Ensuring all pages have been split into one fragment initially: - * page_pool_set_pp_info() is only called once for every page when it - * is allocated from the page allocator and page_pool_fragment_page() - * is dirtying the same cache line as the page->pp_magic above, so - * the overhead is negligible. - */ - page_pool_fragment_netmem(netmem, 1); - if (pool->has_init_callback) - pool->slow.init_callback(netmem, pool->slow.init_arg); -} - -static void page_pool_clear_pp_info(netmem_ref netmem) -{ - netmem_clear_pp_magic(netmem); - netmem_set_pp(netmem, NULL); -} - static struct page *__page_pool_alloc_page_order(struct page_pool *pool, gfp_t gfp) { --=20 2.45.1.288.g0e0cd299f1-goog