From patchwork Sat Dec 21 00:42:36 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mina Almasry X-Patchwork-Id: 13917567 Received: from mail-pg1-f202.google.com (mail-pg1-f202.google.com [209.85.215.202]) (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 AE8C6150997 for ; Sat, 21 Dec 2024 00:51:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.215.202 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734742305; cv=none; b=eOBp4F21lpnMYUB1qABLUPf9cUqBPybXRoRxVNqelznZhsh0fYnTHzKWyhnaZF8w8yW0P+N4VuytScnf4bWNtT8yMJoJradAJf8M6O3hu0LrraVr1zAm+8OjbVnDJHxkUtJ5MA6or88geIeLvcMZFptL9YFPWVUX39LVjWdRPg8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734742305; c=relaxed/simple; bh=IINc7iQX/r7LYdrEQhak9aKmKhNQAg2DZGRwc2+9I94=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=tW3WY7vTFThFhs9Qitg35ttl1HUwrKxfrKJwjnDz2ySPlN/AYbmrdiuVLQXL0YrzleKJv5j+HDm8T3NRu81GSPdUhdJlg7qHvVi3G//UydDbiYgwie1jCYcHawgZ5bZPsWxS5Uj3UEDQZwfZfd4sJOc8aPLGs26pcqCpL/pygTE= 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=xV4ZicyZ; arc=none smtp.client-ip=209.85.215.202 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="xV4ZicyZ" Received: by mail-pg1-f202.google.com with SMTP id 41be03b00d2f7-801d5add29eso1620322a12.3 for ; Fri, 20 Dec 2024 16:51:42 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1734742302; x=1735347102; 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=NZSE0w2/Y5onWcsN4W4n34gva14f/out2BJyIZxl9Q0=; b=xV4ZicyZwFJdWRL2dv9PUY3tgBZgnIpCS+y150QqyxXxYbeq9NOzpmIowsP745p8Uc 0qSBRUH3VE6OOJJUg53rvjdFQv2pUZaA5yhEeVxcEiOFqx95TgnU29jq6FX1KQYGIFdQ BDcSmEUcKcko5RafqvpKJDstIb3vSzYbS8V+DiX5LLlxxkwIW55s9lhNoiF/zNkPp8E4 PMeWb7En6wbMIjsDbN9BlqZoTo7Ky/UqxQTGyVh+KC8vzwwL2cfZOiO4KUEcvNlmOjmM 5Ty8n6IsDClerws0mkP+568cKV0BI59c1pdr9VLk89CCCvQq1UyBJcUYXH0sQNUZoV3v Cp3Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1734742302; x=1735347102; 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=NZSE0w2/Y5onWcsN4W4n34gva14f/out2BJyIZxl9Q0=; b=S7ZKCLhD/JeyaCmUrQLpDpm5uPxhoAoyw7Fu00ZUJF0arJyr47SwF4OgN34dLpdK+z CkiuaRK63J0+xm/QqneNeG7DQvoUHiiG7taVhymga5ZGFLFlHF3W8jOkYn/1lf1IIS/V ovTKc1N0Ehljo6gE5BTlSyT0i38GvVjAyEoh0UyNtAkryTHZDkREzi+Btg7PpdAAruS5 O+LF7Ti52WlSgCeza5R3fqz/BJIY48URf/OTlmQ/tTpM3gcIHUTALHUUbc4jTqgSqkKX vkcACcs5L+LyU9Fl2a0UHRaXO3GtyallWylHOVCIRLqkA2gORIwp6jxGfVBj1BeQJasZ Olyg== X-Forwarded-Encrypted: i=1; AJvYcCXtErDPcpBWIAOfxRMMIWkwzqVdM1S2fcwuD7MKYoZki5WYCsPplRjoPyhlEopDSbw4ypA=@vger.kernel.org X-Gm-Message-State: AOJu0YxGFif/z3thZ+ptQi8sgzXe2xWBuNri+wLaJfuIyGImhag+5D8H YrIBu/LyKz1q/1CdtVOB+dNDJhzPZZKHWc7+69bGtJ2EzFT2OPDYSMYByuZK1N1VHSoS+k5pnMh 9CJfqNENFSqUqFTVMvtlC4g== X-Google-Smtp-Source: AGHT+IEVonbxTJJnb/MSXmpgW2Kj8xiEDkigF5HqD2BqY7pxwYAoFbcUNdEZ7bbAazV4BPucfe0/kWlx29dFavSHaw== X-Received: from pgjo21.prod.google.com ([2002:a63:e355:0:b0:826:36c0:d549]) (user=almasrymina job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a20:258c:b0:1db:915b:ab11 with SMTP id adf61e73a8af0-1e5e04946b1mr9353594637.24.1734742301979; Fri, 20 Dec 2024 16:51:41 -0800 (PST) Date: Sat, 21 Dec 2024 00:42:36 +0000 In-Reply-To: <20241221004236.2629280-1-almasrymina@google.com> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20241221004236.2629280-1-almasrymina@google.com> X-Mailer: git-send-email 2.47.1.613.gc27f4b7a9f-goog Message-ID: <20241221004236.2629280-6-almasrymina@google.com> Subject: [PATCH RFC net-next v1 5/5] net: devmem: Implement TX path From: Mina Almasry To: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, virtualization@lists.linux.dev, kvm@vger.kernel.org, linux-kselftest@vger.kernel.org Cc: Mina Almasry , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , Donald Hunter , Jonathan Corbet , Andrew Lunn , David Ahern , "Michael S. Tsirkin" , Jason Wang , Xuan Zhuo , " =?utf-8?q?Eugenio_P=C3=A9rez?= " , Stefan Hajnoczi , Stefano Garzarella , Shuah Khan , Kaiyuan Zhang , Pavel Begunkov , Willem de Bruijn , Samiullah Khawaja , Stanislav Fomichev , Joe Damato , dw@davidwei.uk Augment dmabuf binding to be able to handle TX. Additional to all the RX binding, we also create tx_vec and tx_iter needed for the TX path. Provide API for sendmsg to be able to send dmabufs bound to this device: - Provide a new dmabuf_tx_cmsg which includes the dmabuf to send from, and the offset into the dmabuf to send from. - MSG_ZEROCOPY with SCM_DEVMEM_DMABUF cmsg indicates send from dma-buf. Devmem is uncopyable, so piggyback off the existing MSG_ZEROCOPY implementation, while disabling instances where MSG_ZEROCOPY falls back to copying. We additionally look up the dmabuf to send from by id, then pipe the binding down to the new zerocopy_fill_skb_from_devmem which fills a TX skb with net_iov netmems instead of the traditional page netmems. We also special case skb_frag_dma_map to return the dma-address of these dmabuf net_iovs instead of attempting to map pages. Based on work by Stanislav Fomichev . A lot of the meat of the implementation came from devmem TCP RFC v1[1], which included the TX path, but Stan did all the rebasing on top of netmem/net_iov. Cc: Stanislav Fomichev Signed-off-by: Kaiyuan Zhang Signed-off-by: Mina Almasry --- include/linux/skbuff.h | 13 +++- include/net/sock.h | 2 + include/uapi/linux/uio.h | 5 ++ net/core/datagram.c | 40 ++++++++++- net/core/devmem.c | 91 +++++++++++++++++++++++-- net/core/devmem.h | 40 +++++++++-- net/core/netdev-genl.c | 65 +++++++++++++++++- net/core/skbuff.c | 8 ++- net/core/sock.c | 9 +++ net/ipv4/tcp.c | 36 +++++++--- net/vmw_vsock/virtio_transport_common.c | 4 +- 11 files changed, 281 insertions(+), 32 deletions(-) diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index bb2b751d274a..e90dc0c4d542 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -1711,9 +1711,10 @@ struct ubuf_info *msg_zerocopy_realloc(struct sock *sk, size_t size, void msg_zerocopy_put_abort(struct ubuf_info *uarg, bool have_uref); +struct net_devmem_dmabuf_binding; int __zerocopy_sg_from_iter(struct msghdr *msg, struct sock *sk, struct sk_buff *skb, struct iov_iter *from, - size_t length); + size_t length, bool is_devmem); int zerocopy_fill_skb_from_iter(struct sk_buff *skb, struct iov_iter *from, size_t length); @@ -1721,12 +1722,14 @@ int zerocopy_fill_skb_from_iter(struct sk_buff *skb, static inline int skb_zerocopy_iter_dgram(struct sk_buff *skb, struct msghdr *msg, int len) { - return __zerocopy_sg_from_iter(msg, skb->sk, skb, &msg->msg_iter, len); + return __zerocopy_sg_from_iter(msg, skb->sk, skb, &msg->msg_iter, len, + false); } int skb_zerocopy_iter_stream(struct sock *sk, struct sk_buff *skb, struct msghdr *msg, int len, - struct ubuf_info *uarg); + struct ubuf_info *uarg, + struct net_devmem_dmabuf_binding *binding); /* Internal */ #define skb_shinfo(SKB) ((struct skb_shared_info *)(skb_end_pointer(SKB))) @@ -3697,6 +3700,10 @@ static inline dma_addr_t __skb_frag_dma_map(struct device *dev, size_t offset, size_t size, enum dma_data_direction dir) { + if (skb_frag_is_net_iov(frag)) { + return netmem_to_net_iov(frag->netmem)->dma_addr + offset + + frag->offset; + } return dma_map_page(dev, skb_frag_page(frag), skb_frag_off(frag) + offset, size, dir); } diff --git a/include/net/sock.h b/include/net/sock.h index d4bdd3286e03..75bd580fe9c6 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -1816,6 +1816,8 @@ struct sockcm_cookie { u32 tsflags; u32 ts_opt_id; u32 priority; + u32 dmabuf_id; + u64 dmabuf_offset; }; static inline void sockcm_init(struct sockcm_cookie *sockc, diff --git a/include/uapi/linux/uio.h b/include/uapi/linux/uio.h index 649739e0c404..41490cde95ad 100644 --- a/include/uapi/linux/uio.h +++ b/include/uapi/linux/uio.h @@ -38,6 +38,11 @@ struct dmabuf_token { __u32 token_count; }; +struct dmabuf_tx_cmsg { + __u32 dmabuf_id; + __u64 dmabuf_offset; +}; + /* * UIO_MAXIOV shall be at least 16 1003.1g (5.4.1.1) */ diff --git a/net/core/datagram.c b/net/core/datagram.c index f0693707aece..3b09995db894 100644 --- a/net/core/datagram.c +++ b/net/core/datagram.c @@ -63,6 +63,8 @@ #include #include +#include "devmem.h" + /* * Is a socket 'connection oriented' ? */ @@ -692,9 +694,41 @@ int zerocopy_fill_skb_from_iter(struct sk_buff *skb, return 0; } +static int zerocopy_fill_skb_from_devmem(struct sk_buff *skb, + struct msghdr *msg, + struct iov_iter *from, int length) +{ + int i = skb_shinfo(skb)->nr_frags; + int orig_length = length; + netmem_ref netmem; + size_t size; + + while (length && iov_iter_count(from)) { + if (i == MAX_SKB_FRAGS) + return -EMSGSIZE; + + size = min_t(size_t, iter_iov_len(from), length); + if (!size) + return -EFAULT; + + netmem = net_iov_to_netmem(iter_iov(from)->iov_base); + get_netmem(netmem); + skb_add_rx_frag_netmem(skb, i, netmem, from->iov_offset, size, + PAGE_SIZE); + + iov_iter_advance(from, size); + length -= size; + i++; + } + + iov_iter_advance(&msg->msg_iter, orig_length); + + return 0; +} + int __zerocopy_sg_from_iter(struct msghdr *msg, struct sock *sk, struct sk_buff *skb, struct iov_iter *from, - size_t length) + size_t length, bool is_devmem) { unsigned long orig_size = skb->truesize; unsigned long truesize; @@ -702,6 +736,8 @@ int __zerocopy_sg_from_iter(struct msghdr *msg, struct sock *sk, if (msg && msg->msg_ubuf && msg->sg_from_iter) ret = msg->sg_from_iter(skb, from, length); + else if (unlikely(is_devmem)) + ret = zerocopy_fill_skb_from_devmem(skb, msg, from, length); else ret = zerocopy_fill_skb_from_iter(skb, from, length); @@ -735,7 +771,7 @@ int zerocopy_sg_from_iter(struct sk_buff *skb, struct iov_iter *from) if (skb_copy_datagram_from_iter(skb, 0, from, copy)) return -EFAULT; - return __zerocopy_sg_from_iter(NULL, NULL, skb, from, ~0U); + return __zerocopy_sg_from_iter(NULL, NULL, skb, from, ~0U, NULL); } EXPORT_SYMBOL(zerocopy_sg_from_iter); diff --git a/net/core/devmem.c b/net/core/devmem.c index f7e06a8cba01..81f1b715cfa6 100644 --- a/net/core/devmem.c +++ b/net/core/devmem.c @@ -15,6 +15,7 @@ #include #include #include +#include #include #include "devmem.h" @@ -63,8 +64,10 @@ void __net_devmem_dmabuf_binding_free(struct net_devmem_dmabuf_binding *binding) dma_buf_detach(binding->dmabuf, binding->attachment); dma_buf_put(binding->dmabuf); xa_destroy(&binding->bound_rxqs); + kfree(binding->tx_vec); kfree(binding); } +EXPORT_SYMBOL(__net_devmem_dmabuf_binding_free); struct net_iov * net_devmem_alloc_dmabuf(struct net_devmem_dmabuf_binding *binding) @@ -109,6 +112,13 @@ void net_devmem_unbind_dmabuf(struct net_devmem_dmabuf_binding *binding) unsigned long xa_idx; unsigned int rxq_idx; + xa_erase(&net_devmem_dmabuf_bindings, binding->id); + + /* Ensure no tx net_devmem_lookup_dmabuf() are in flight after the + * erase. + */ + synchronize_net(); + if (binding->list.next) list_del(&binding->list); @@ -122,8 +132,6 @@ void net_devmem_unbind_dmabuf(struct net_devmem_dmabuf_binding *binding) WARN_ON(netdev_rx_queue_restart(binding->dev, rxq_idx)); } - xa_erase(&net_devmem_dmabuf_bindings, binding->id); - net_devmem_dmabuf_binding_put(binding); } @@ -174,8 +182,9 @@ int net_devmem_bind_dmabuf_to_queue(struct net_device *dev, u32 rxq_idx, } struct net_devmem_dmabuf_binding * -net_devmem_bind_dmabuf(struct net_device *dev, unsigned int dmabuf_fd, - struct netlink_ext_ack *extack) +net_devmem_bind_dmabuf(struct net_device *dev, + enum dma_data_direction direction, + unsigned int dmabuf_fd, struct netlink_ext_ack *extack) { struct net_devmem_dmabuf_binding *binding; static u32 id_alloc_next; @@ -183,6 +192,7 @@ net_devmem_bind_dmabuf(struct net_device *dev, unsigned int dmabuf_fd, struct dma_buf *dmabuf; unsigned int sg_idx, i; unsigned long virtual; + struct iovec *iov; int err; dmabuf = dma_buf_get(dmabuf_fd); @@ -218,13 +228,19 @@ net_devmem_bind_dmabuf(struct net_device *dev, unsigned int dmabuf_fd, } binding->sgt = dma_buf_map_attachment_unlocked(binding->attachment, - DMA_FROM_DEVICE); + direction); if (IS_ERR(binding->sgt)) { err = PTR_ERR(binding->sgt); NL_SET_ERR_MSG(extack, "Failed to map dmabuf attachment"); goto err_detach; } + if (!binding->sgt || binding->sgt->nents == 0) { + err = -EINVAL; + NL_SET_ERR_MSG(extack, "Empty dmabuf attachment"); + goto err_detach; + } + /* For simplicity we expect to make PAGE_SIZE allocations, but the * binding can be much more flexible than that. We may be able to * allocate MTU sized chunks here. Leave that for future work... @@ -236,6 +252,19 @@ net_devmem_bind_dmabuf(struct net_device *dev, unsigned int dmabuf_fd, goto err_unmap; } + if (direction == DMA_TO_DEVICE) { + virtual = 0; + for_each_sgtable_dma_sg(binding->sgt, sg, sg_idx) + virtual += sg_dma_len(sg); + + binding->tx_vec = kcalloc(virtual / PAGE_SIZE + 1, + sizeof(struct iovec), GFP_KERNEL); + if (!binding->tx_vec) { + err = -ENOMEM; + goto err_unmap; + } + } + virtual = 0; for_each_sgtable_dma_sg(binding->sgt, sg, sg_idx) { dma_addr_t dma_addr = sg_dma_address(sg); @@ -277,11 +306,21 @@ net_devmem_bind_dmabuf(struct net_device *dev, unsigned int dmabuf_fd, niov->owner = owner; page_pool_set_dma_addr_netmem(net_iov_to_netmem(niov), net_devmem_get_dma_addr(niov)); + + if (direction == DMA_TO_DEVICE) { + iov = &binding->tx_vec[virtual / PAGE_SIZE + i]; + iov->iov_base = niov; + iov->iov_len = PAGE_SIZE; + } } virtual += len; } + if (direction == DMA_TO_DEVICE) + iov_iter_init(&binding->tx_iter, WRITE, binding->tx_vec, + virtual / PAGE_SIZE + 1, virtual); + return binding; err_free_chunks: @@ -302,6 +341,21 @@ net_devmem_bind_dmabuf(struct net_device *dev, unsigned int dmabuf_fd, return ERR_PTR(err); } +struct net_devmem_dmabuf_binding *net_devmem_lookup_dmabuf(u32 id) +{ + struct net_devmem_dmabuf_binding *binding; + + rcu_read_lock(); + binding = xa_load(&net_devmem_dmabuf_bindings, id); + if (binding) { + if (!net_devmem_dmabuf_binding_get(binding)) + binding = NULL; + } + rcu_read_unlock(); + + return binding; +} + void dev_dmabuf_uninstall(struct net_device *dev) { struct net_devmem_dmabuf_binding *binding; @@ -332,6 +386,33 @@ void net_devmem_put_net_iov(struct net_iov *niov) net_devmem_dmabuf_binding_put(niov->owner->binding); } +struct net_devmem_dmabuf_binding * +net_devmem_get_sockc_binding(struct sock *sk, struct sockcm_cookie *sockc) +{ + struct net_devmem_dmabuf_binding *binding; + int err = 0; + + binding = net_devmem_lookup_dmabuf(sockc->dmabuf_id); + if (!binding || !binding->tx_vec) { + err = -EINVAL; + goto out_err; + } + + if (sock_net(sk) != dev_net(binding->dev)) { + err = -ENODEV; + goto out_err; + } + + iov_iter_advance(&binding->tx_iter, sockc->dmabuf_offset); + return binding; + +out_err: + if (binding) + net_devmem_dmabuf_binding_put(binding); + + return ERR_PTR(err); +} + /*** "Dmabuf devmem memory provider" ***/ int mp_dmabuf_devmem_init(struct page_pool *pool) diff --git a/net/core/devmem.h b/net/core/devmem.h index 54e30fea80b3..f923c77d9c45 100644 --- a/net/core/devmem.h +++ b/net/core/devmem.h @@ -11,6 +11,8 @@ #define _NET_DEVMEM_H struct netlink_ext_ack; +struct sockcm_cookie; +struct sock; struct net_devmem_dmabuf_binding { struct dma_buf *dmabuf; @@ -27,6 +29,10 @@ struct net_devmem_dmabuf_binding { * The binding undos itself and unmaps the underlying dmabuf once all * those refs are dropped and the binding is no longer desired or in * use. + * + * net_devmem_get_net_iov() on dmabuf net_iovs will increment this + * reference, making sure that that the binding remains alive until all + * the net_iovs are no longer used. */ refcount_t ref; @@ -42,6 +48,10 @@ struct net_devmem_dmabuf_binding { * active. */ u32 id; + + /* iov_iter representing all possible net_iov chunks in the dmabuf. */ + struct iov_iter tx_iter; + struct iovec *tx_vec; }; #if defined(CONFIG_NET_DEVMEM) @@ -66,8 +76,10 @@ struct dmabuf_genpool_chunk_owner { void __net_devmem_dmabuf_binding_free(struct net_devmem_dmabuf_binding *binding); struct net_devmem_dmabuf_binding * -net_devmem_bind_dmabuf(struct net_device *dev, unsigned int dmabuf_fd, - struct netlink_ext_ack *extack); +net_devmem_bind_dmabuf(struct net_device *dev, + enum dma_data_direction direction, + unsigned int dmabuf_fd, struct netlink_ext_ack *extack); +struct net_devmem_dmabuf_binding *net_devmem_lookup_dmabuf(u32 id); void net_devmem_unbind_dmabuf(struct net_devmem_dmabuf_binding *binding); int net_devmem_bind_dmabuf_to_queue(struct net_device *dev, u32 rxq_idx, struct net_devmem_dmabuf_binding *binding, @@ -104,10 +116,10 @@ static inline u32 net_iov_binding_id(const struct net_iov *niov) return net_iov_owner(niov)->binding->id; } -static inline void +static inline bool net_devmem_dmabuf_binding_get(struct net_devmem_dmabuf_binding *binding) { - refcount_inc(&binding->ref); + return refcount_inc_not_zero(&binding->ref); } static inline void @@ -126,6 +138,9 @@ struct net_iov * net_devmem_alloc_dmabuf(struct net_devmem_dmabuf_binding *binding); void net_devmem_free_dmabuf(struct net_iov *ppiov); +struct net_devmem_dmabuf_binding * +net_devmem_get_sockc_binding(struct sock *sk, struct sockcm_cookie *sockc); + #else struct net_devmem_dmabuf_binding; @@ -144,11 +159,17 @@ __net_devmem_dmabuf_binding_free(struct net_devmem_dmabuf_binding *binding) static inline struct net_devmem_dmabuf_binding * net_devmem_bind_dmabuf(struct net_device *dev, unsigned int dmabuf_fd, + enum dma_data_direction direction, struct netlink_ext_ack *extack) { return ERR_PTR(-EOPNOTSUPP); } +static inline struct net_devmem_dmabuf_binding *net_devmem_lookup_dmabuf(u32 id) +{ + return NULL; +} + static inline void net_devmem_unbind_dmabuf(struct net_devmem_dmabuf_binding *binding) { @@ -186,6 +207,17 @@ static inline u32 net_iov_binding_id(const struct net_iov *niov) { return 0; } + +static inline void +net_devmem_dmabuf_binding_put(struct net_devmem_dmabuf_binding *binding) +{ +} + +static inline struct net_devmem_dmabuf_binding * +net_devmem_get_sockc_binding(struct sock *sk, struct sockcm_cookie *sockc) +{ + return ERR_PTR(-EOPNOTSUPP); +} #endif #endif /* _NET_DEVMEM_H */ diff --git a/net/core/netdev-genl.c b/net/core/netdev-genl.c index 00d3d5851487..b9928bac94da 100644 --- a/net/core/netdev-genl.c +++ b/net/core/netdev-genl.c @@ -850,7 +850,8 @@ int netdev_nl_bind_rx_doit(struct sk_buff *skb, struct genl_info *info) goto err_unlock; } - binding = net_devmem_bind_dmabuf(netdev, dmabuf_fd, info->extack); + binding = net_devmem_bind_dmabuf(netdev, DMA_FROM_DEVICE, dmabuf_fd, + info->extack); if (IS_ERR(binding)) { err = PTR_ERR(binding); goto err_unlock; @@ -907,10 +908,68 @@ int netdev_nl_bind_rx_doit(struct sk_buff *skb, struct genl_info *info) return err; } -/* stub */ int netdev_nl_bind_tx_doit(struct sk_buff *skb, struct genl_info *info) { - return 0; + struct net_devmem_dmabuf_binding *binding; + struct list_head *sock_binding_list; + struct net_device *netdev; + u32 ifindex, dmabuf_fd; + struct sk_buff *rsp; + int err = 0; + void *hdr; + + if (GENL_REQ_ATTR_CHECK(info, NETDEV_A_DEV_IFINDEX) || + GENL_REQ_ATTR_CHECK(info, NETDEV_A_DMABUF_FD)) + return -EINVAL; + + ifindex = nla_get_u32(info->attrs[NETDEV_A_DEV_IFINDEX]); + dmabuf_fd = nla_get_u32(info->attrs[NETDEV_A_DMABUF_FD]); + + sock_binding_list = + genl_sk_priv_get(&netdev_nl_family, NETLINK_CB(skb).sk); + if (IS_ERR(sock_binding_list)) + return PTR_ERR(sock_binding_list); + + rsp = genlmsg_new(GENLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!rsp) + return -ENOMEM; + + hdr = genlmsg_iput(rsp, info); + if (!hdr) { + err = -EMSGSIZE; + goto err_genlmsg_free; + } + + rtnl_lock(); + + netdev = __dev_get_by_index(genl_info_net(info), ifindex); + if (!netdev || !netif_device_present(netdev)) { + err = -ENODEV; + goto err_unlock; + } + + binding = net_devmem_bind_dmabuf(netdev, DMA_TO_DEVICE, dmabuf_fd, + info->extack); + if (IS_ERR(binding)) { + err = PTR_ERR(binding); + goto err_unlock; + } + + list_add(&binding->list, sock_binding_list); + + nla_put_u32(rsp, NETDEV_A_DMABUF_ID, binding->id); + genlmsg_end(rsp, hdr); + + rtnl_unlock(); + + return genlmsg_reply(rsp, info); + + net_devmem_unbind_dmabuf(binding); +err_unlock: + rtnl_unlock(); +err_genlmsg_free: + nlmsg_free(rsp); + return err; } void netdev_nl_sock_priv_init(struct list_head *priv) diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 815245d5c36b..eb6b41a32524 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -1882,8 +1882,10 @@ EXPORT_SYMBOL_GPL(msg_zerocopy_ubuf_ops); int skb_zerocopy_iter_stream(struct sock *sk, struct sk_buff *skb, struct msghdr *msg, int len, - struct ubuf_info *uarg) + struct ubuf_info *uarg, + struct net_devmem_dmabuf_binding *binding) { + struct iov_iter *from = binding ? &binding->tx_iter : &msg->msg_iter; int err, orig_len = skb->len; if (uarg->ops->link_skb) { @@ -1901,12 +1903,12 @@ int skb_zerocopy_iter_stream(struct sock *sk, struct sk_buff *skb, return -EEXIST; } - err = __zerocopy_sg_from_iter(msg, sk, skb, &msg->msg_iter, len); + err = __zerocopy_sg_from_iter(msg, sk, skb, from, len, binding != NULL); if (err == -EFAULT || (err == -EMSGSIZE && skb->len == orig_len)) { struct sock *save_sk = skb->sk; /* Streams do not free skb on error. Reset to prev state. */ - iov_iter_revert(&msg->msg_iter, skb->len - orig_len); + iov_iter_revert(from, skb->len - orig_len); skb->sk = sk; ___pskb_trim(skb, orig_len); skb->sk = save_sk; diff --git a/net/core/sock.c b/net/core/sock.c index e7bcc8952248..ed7089310f0d 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -2908,6 +2908,7 @@ EXPORT_SYMBOL(sock_alloc_send_pskb); int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg, struct sockcm_cookie *sockc) { + struct dmabuf_tx_cmsg dmabuf_tx; u32 tsflags; BUILD_BUG_ON(SOF_TIMESTAMPING_LAST == (1 << 31)); @@ -2961,6 +2962,14 @@ int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg, if (!sk_set_prio_allowed(sk, *(u32 *)CMSG_DATA(cmsg))) return -EPERM; sockc->priority = *(u32 *)CMSG_DATA(cmsg); + break; + case SCM_DEVMEM_DMABUF: + if (cmsg->cmsg_len != CMSG_LEN(sizeof(struct dmabuf_tx_cmsg))) + return -EINVAL; + dmabuf_tx = *(struct dmabuf_tx_cmsg *)CMSG_DATA(cmsg); + sockc->dmabuf_id = dmabuf_tx.dmabuf_id; + sockc->dmabuf_offset = dmabuf_tx.dmabuf_offset; + break; default: return -EINVAL; diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 0d704bda6c41..406dc2993742 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -1051,6 +1051,7 @@ int tcp_sendmsg_fastopen(struct sock *sk, struct msghdr *msg, int *copied, int tcp_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t size) { + struct net_devmem_dmabuf_binding *binding = NULL; struct tcp_sock *tp = tcp_sk(sk); struct ubuf_info *uarg = NULL; struct sk_buff *skb; @@ -1063,6 +1064,15 @@ int tcp_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t size) flags = msg->msg_flags; + sockcm_init(&sockc, sk); + if (msg->msg_controllen) { + err = sock_cmsg_send(sk, msg, &sockc); + if (unlikely(err)) { + err = -EINVAL; + goto out_err; + } + } + if ((flags & MSG_ZEROCOPY) && size) { if (msg->msg_ubuf) { uarg = msg->msg_ubuf; @@ -1080,6 +1090,15 @@ int tcp_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t size) else uarg_to_msgzc(uarg)->zerocopy = 0; } + + if (sockc.dmabuf_id != 0) { + binding = net_devmem_get_sockc_binding(sk, &sockc); + if (IS_ERR(binding)) { + err = PTR_ERR(binding); + binding = NULL; + goto out_err; + } + } } else if (unlikely(msg->msg_flags & MSG_SPLICE_PAGES) && size) { if (sk->sk_route_caps & NETIF_F_SG) zc = MSG_SPLICE_PAGES; @@ -1123,15 +1142,6 @@ int tcp_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t size) /* 'common' sending to sendq */ } - sockcm_init(&sockc, sk); - if (msg->msg_controllen) { - err = sock_cmsg_send(sk, msg, &sockc); - if (unlikely(err)) { - err = -EINVAL; - goto out_err; - } - } - /* This should be in poll */ sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk); @@ -1248,7 +1258,8 @@ int tcp_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t size) goto wait_for_space; } - err = skb_zerocopy_iter_stream(sk, skb, msg, copy, uarg); + err = skb_zerocopy_iter_stream(sk, skb, msg, copy, uarg, + binding); if (err == -EMSGSIZE || err == -EEXIST) { tcp_mark_push(tp, skb); goto new_segment; @@ -1329,6 +1340,8 @@ int tcp_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t size) /* msg->msg_ubuf is pinned by the caller so we don't take extra refs */ if (uarg && !msg->msg_ubuf) net_zcopy_put(uarg); + if (binding) + net_devmem_dmabuf_binding_put(binding); return copied + copied_syn; do_error: @@ -1346,6 +1359,9 @@ int tcp_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t size) sk->sk_write_space(sk); tcp_chrono_stop(sk, TCP_CHRONO_SNDBUF_LIMITED); } + if (binding) + net_devmem_dmabuf_binding_put(binding); + return err; } EXPORT_SYMBOL_GPL(tcp_sendmsg_locked); diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c index 9acc13ab3f82..286e6cd5ad34 100644 --- a/net/vmw_vsock/virtio_transport_common.c +++ b/net/vmw_vsock/virtio_transport_common.c @@ -104,8 +104,8 @@ static int virtio_transport_fill_skb(struct sk_buff *skb, { if (zcopy) return __zerocopy_sg_from_iter(info->msg, NULL, skb, - &info->msg->msg_iter, - len); + &info->msg->msg_iter, len, + false); return memcpy_from_msg(skb_put(skb, len), info->msg, len); }