From nobody Mon Nov 10 17:38:23 2025 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 0BA30EB64DD for ; Wed, 19 Jul 2023 00:50:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229988AbjGSAux (ORCPT ); Tue, 18 Jul 2023 20:50:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46432 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229825AbjGSAuk (ORCPT ); Tue, 18 Jul 2023 20:50:40 -0400 Received: from mail-qk1-x735.google.com (mail-qk1-x735.google.com [IPv6:2607:f8b0:4864:20::735]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 14086194 for ; Tue, 18 Jul 2023 17:50:13 -0700 (PDT) Received: by mail-qk1-x735.google.com with SMTP id af79cd13be357-7673180224bso430068385a.0 for ; Tue, 18 Jul 2023 17:50:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance.com; s=google; t=1689727812; x=1692319812; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:from:to:cc:subject:date:message-id :reply-to; bh=fTdq57d4OfXfe2GYZwwn7VN2X/kQP6RwUR6JDFxPMEE=; b=CwqkbU54GND2d0NRs1umFXWwgm1JIjPjAPvnk1NY83WcuEGBPYkuDQYXZFb7iBYMKA r3O8KmNKOULw1yvMv6pIMstrnYMj7AtDVb4D1Ob0dWGESArGh0wsM8p36Iq0Wib3Vfsa z9zbHt2B6ZRbhDvyRhpQhAsNDvr2JTcfC0Tv44w2+9lc9g6nb1WHD8/tLjH6mxq930JY QDLmg5IZchtTh3E0U79Zezbq6DpAQXO27VkJwNpECv4EmtcxWxYQj+GZNJSUmbsUrfuA M50BWMRsjrJ0p9mKh0R3elh37onXk8adWkQvdzGEvXgSaVvGXMPVmylx1mCqDObk9XFE y+pQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1689727812; x=1692319812; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=fTdq57d4OfXfe2GYZwwn7VN2X/kQP6RwUR6JDFxPMEE=; b=YP8O+hJqz2PbQJLZJazJE/ShSdOeSHASNo/Q6tMj30bQWaQdlKDw405p/n8uGpr3YO WfweU4bbk1xud42VO6ocVsPDhj/TtW3LEjoVMAqDc1vjpRmmFKYZBJEybd0IucCHHfEB mpd/fa27MXQwXQ3R+YK5z7WrGOp8Tt14RfTY1hfPwQ4QUq3Wlf2jIDwF+H04WgFUtoVP VhZRccI+AjZ02QwfPYmJAfV4LvXUqZPd1CkaBmBYHy4c6dkac6B/I1mkwaz3MYayruRd 1sNiX90Ig8lZFu2p65qtWS64B4TghSMQOg4q+qTyCkh+mG+b6JneoURm1meWervWHvbA jdTQ== X-Gm-Message-State: ABy/qLbIogIePpMs2W8ZiDpW0W6GBHvLzgj3HkZ2uwtGSyY3zscEpIAp JjicNMZ6kpzHHowRw6MGS8FJ9A== X-Google-Smtp-Source: APBJJlEP9yfXfRZpd82K8uInRNYu+aKr3VaNkJmbmubQt80ddydBcGIs44T6SoEEPEuALM40rCRIFw== X-Received: by 2002:a05:620a:2902:b0:767:e73b:d051 with SMTP id m2-20020a05620a290200b00767e73bd051mr1699976qkp.32.1689727811917; Tue, 18 Jul 2023 17:50:11 -0700 (PDT) Received: from [172.17.0.7] ([130.44.212.112]) by smtp.gmail.com with ESMTPSA id c5-20020a05620a11a500b0076738337cd1sm968696qkk.1.2023.07.18.17.50.11 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 18 Jul 2023 17:50:11 -0700 (PDT) From: Bobby Eshleman Date: Wed, 19 Jul 2023 00:50:07 +0000 Subject: [PATCH RFC net-next v5 03/14] af_vsock: support multi-transport datagrams MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20230413-b4-vsock-dgram-v5-3-581bd37fdb26@bytedance.com> References: <20230413-b4-vsock-dgram-v5-0-581bd37fdb26@bytedance.com> In-Reply-To: <20230413-b4-vsock-dgram-v5-0-581bd37fdb26@bytedance.com> To: Stefan Hajnoczi , Stefano Garzarella , "Michael S. Tsirkin" , Jason Wang , Xuan Zhuo , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , "K. Y. Srinivasan" , Haiyang Zhang , Wei Liu , Dexuan Cui , Bryan Tan , Vishnu Dasa , VMware PV-Drivers Reviewers Cc: Dan Carpenter , Simon Horman , Krasnov Arseniy , kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-hyperv@vger.kernel.org, bpf@vger.kernel.org, Bobby Eshleman X-Mailer: b4 0.12.2 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch adds support for multi-transport datagrams. This includes: - Per-packet lookup of transports when using sendto(sockaddr_vm) - Selecting H2G or G2H transport using VMADDR_FLAG_TO_HOST and CID in sockaddr_vm - rename VSOCK_TRANSPORT_F_DGRAM to VSOCK_TRANSPORT_F_DGRAM_FALLBACK - connect() now assigns the transport for (similar to connectible sockets) To preserve backwards compatibility with VMCI, some important changes are made. The "transport_dgram" / VSOCK_TRANSPORT_F_DGRAM is changed to be used for dgrams only if there is not yet a g2h or h2g transport that has been registered that can transmit the packet. If there is a g2h/h2g transport for that remote address, then that transport will be used and not "transport_dgram". This essentially makes "transport_dgram" a fallback transport for when h2g/g2h has not yet gone online, and so it is renamed "transport_dgram_fallback". VMCI implements this transport. The logic around "transport_dgram" needs to be retained to prevent breaking VMCI: 1) VMCI datagrams existed prior to h2g/g2h and so operate under a different paradigm. When the vmci transport comes online, it registers itself with the DGRAM feature, but not H2G/G2H. Only later when the transport has more information about its environment does it register H2G or G2H. In the case that a datagram socket is created after VSOCK_TRANSPORT_F_DGRAM registration but before G2H/H2G registration, the "transport_dgram" transport is the only registered transport and so needs to be used. 2) VMCI seems to require a special message be sent by the transport when a datagram socket calls bind(). Under the h2g/g2h model, the transport is selected using the remote_addr which is set by connect(). At bind time there is no remote_addr because often no connect() has been called yet: the transport is null. Therefore, with a null transport there doesn't seem to be any good way for a datagram socket to tell the VMCI transport that it has just had bind() called upon it. With the new fallback logic, after H2G/G2H comes online the socket layer will access the VMCI transport via transport_{h2g,g2h}. Prior to H2G/G2H coming online, the socket layer will access the VMCI transport via "transport_dgram_fallback". Only transports with a special datagram fallback use-case such as VMCI need to register VSOCK_TRANSPORT_F_DGRAM_FALLBACK. Signed-off-by: Bobby Eshleman --- drivers/vhost/vsock.c | 1 - include/linux/virtio_vsock.h | 2 -- include/net/af_vsock.h | 10 +++--- net/vmw_vsock/af_vsock.c | 64 ++++++++++++++++++++++++++---= ---- net/vmw_vsock/hyperv_transport.c | 6 ---- net/vmw_vsock/virtio_transport.c | 1 - net/vmw_vsock/virtio_transport_common.c | 7 ---- net/vmw_vsock/vmci_transport.c | 2 +- net/vmw_vsock/vsock_loopback.c | 1 - 9 files changed, 58 insertions(+), 36 deletions(-) diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c index ae8891598a48..d5d6a3c3f273 100644 --- a/drivers/vhost/vsock.c +++ b/drivers/vhost/vsock.c @@ -410,7 +410,6 @@ static struct virtio_transport vhost_transport =3D { .cancel_pkt =3D vhost_transport_cancel_pkt, =20 .dgram_enqueue =3D virtio_transport_dgram_enqueue, - .dgram_bind =3D virtio_transport_dgram_bind, .dgram_allow =3D virtio_transport_dgram_allow, =20 .stream_enqueue =3D virtio_transport_stream_enqueue, diff --git a/include/linux/virtio_vsock.h b/include/linux/virtio_vsock.h index 18cbe8d37fca..7632552bee58 100644 --- a/include/linux/virtio_vsock.h +++ b/include/linux/virtio_vsock.h @@ -211,8 +211,6 @@ void virtio_transport_notify_buffer_size(struct vsock_s= ock *vsk, u64 *val); u64 virtio_transport_stream_rcvhiwat(struct vsock_sock *vsk); bool virtio_transport_stream_is_active(struct vsock_sock *vsk); bool virtio_transport_stream_allow(u32 cid, u32 port); -int virtio_transport_dgram_bind(struct vsock_sock *vsk, - struct sockaddr_vm *addr); bool virtio_transport_dgram_allow(u32 cid, u32 port); =20 int virtio_transport_connect(struct vsock_sock *vsk); diff --git a/include/net/af_vsock.h b/include/net/af_vsock.h index 305d57502e89..f6a0ca9d7c3e 100644 --- a/include/net/af_vsock.h +++ b/include/net/af_vsock.h @@ -96,13 +96,13 @@ struct vsock_transport_send_notify_data { =20 /* Transport features flags */ /* Transport provides host->guest communication */ -#define VSOCK_TRANSPORT_F_H2G 0x00000001 +#define VSOCK_TRANSPORT_F_H2G 0x00000001 /* Transport provides guest->host communication */ -#define VSOCK_TRANSPORT_F_G2H 0x00000002 -/* Transport provides DGRAM communication */ -#define VSOCK_TRANSPORT_F_DGRAM 0x00000004 +#define VSOCK_TRANSPORT_F_G2H 0x00000002 +/* Transport provides fallback for DGRAM communication */ +#define VSOCK_TRANSPORT_F_DGRAM_FALLBACK 0x00000004 /* Transport provides local (loopback) communication */ -#define VSOCK_TRANSPORT_F_LOCAL 0x00000008 +#define VSOCK_TRANSPORT_F_LOCAL 0x00000008 =20 struct vsock_transport { struct module *module; diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c index ae5ac5531d96..26c97b33d55a 100644 --- a/net/vmw_vsock/af_vsock.c +++ b/net/vmw_vsock/af_vsock.c @@ -139,8 +139,8 @@ struct proto vsock_proto =3D { static const struct vsock_transport *transport_h2g; /* Transport used for guest->host communication */ static const struct vsock_transport *transport_g2h; -/* Transport used for DGRAM communication */ -static const struct vsock_transport *transport_dgram; +/* Transport used as a fallback for DGRAM communication */ +static const struct vsock_transport *transport_dgram_fallback; /* Transport used for local communication */ static const struct vsock_transport *transport_local; static DEFINE_MUTEX(vsock_register_mutex); @@ -439,6 +439,18 @@ vsock_connectible_lookup_transport(unsigned int cid, _= _u8 flags) return transport; } =20 +static const struct vsock_transport * +vsock_dgram_lookup_transport(unsigned int cid, __u8 flags) +{ + const struct vsock_transport *transport; + + transport =3D vsock_connectible_lookup_transport(cid, flags); + if (transport) + return transport; + + return transport_dgram_fallback; +} + /* Assign a transport to a socket and call the .init transport callback. * * Note: for connection oriented socket this must be called when vsk->remo= te_addr @@ -475,7 +487,8 @@ int vsock_assign_transport(struct vsock_sock *vsk, stru= ct vsock_sock *psk) =20 switch (sk->sk_type) { case SOCK_DGRAM: - new_transport =3D transport_dgram; + new_transport =3D vsock_dgram_lookup_transport(remote_cid, + remote_flags); break; case SOCK_STREAM: case SOCK_SEQPACKET: @@ -692,6 +705,9 @@ static int __vsock_bind_connectible(struct vsock_sock *= vsk, static int __vsock_bind_dgram(struct vsock_sock *vsk, struct sockaddr_vm *addr) { + if (!vsk->transport || !vsk->transport->dgram_bind) + return -EINVAL; + return vsk->transport->dgram_bind(vsk, addr); } =20 @@ -1162,6 +1178,7 @@ static int vsock_dgram_sendmsg(struct socket *sock, s= truct msghdr *msg, struct vsock_sock *vsk; struct sockaddr_vm *remote_addr; const struct vsock_transport *transport; + bool module_got =3D false; =20 if (msg->msg_flags & MSG_OOB) return -EOPNOTSUPP; @@ -1173,19 +1190,34 @@ static int vsock_dgram_sendmsg(struct socket *sock,= struct msghdr *msg, =20 lock_sock(sk); =20 - transport =3D vsk->transport; - err =3D vsock_auto_bind(vsk); if (err) goto out; =20 - /* If the provided message contains an address, use that. Otherwise * fall back on the socket's remote handle (if it has been connected). */ if (msg->msg_name && vsock_addr_cast(msg->msg_name, msg->msg_namelen, &remote_addr) =3D=3D 0) { + transport =3D vsock_dgram_lookup_transport(remote_addr->svm_cid, + remote_addr->svm_flags); + if (!transport) { + err =3D -EINVAL; + goto out; + } + + if (!try_module_get(transport->module)) { + err =3D -ENODEV; + goto out; + } + + /* When looking up a transport dynamically and acquiring a + * reference on the module, we need to remember to release the + * reference later. + */ + module_got =3D true; + /* Ensure this address is of the right type and is a valid * destination. */ @@ -1200,6 +1232,7 @@ static int vsock_dgram_sendmsg(struct socket *sock, s= truct msghdr *msg, } else if (sock->state =3D=3D SS_CONNECTED) { remote_addr =3D &vsk->remote_addr; =20 + transport =3D vsk->transport; if (remote_addr->svm_cid =3D=3D VMADDR_CID_ANY) remote_addr->svm_cid =3D transport->get_local_cid(); =20 @@ -1224,6 +1257,8 @@ static int vsock_dgram_sendmsg(struct socket *sock, s= truct msghdr *msg, err =3D transport->dgram_enqueue(vsk, remote_addr, msg, len); =20 out: + if (module_got) + module_put(transport->module); release_sock(sk); return err; } @@ -1256,13 +1291,18 @@ static int vsock_dgram_connect(struct socket *sock, if (err) goto out; =20 + memcpy(&vsk->remote_addr, remote_addr, sizeof(vsk->remote_addr)); + + err =3D vsock_assign_transport(vsk, NULL); + if (err) + goto out; + if (!vsk->transport->dgram_allow(remote_addr->svm_cid, remote_addr->svm_port)) { err =3D -EINVAL; goto out; } =20 - memcpy(&vsk->remote_addr, remote_addr, sizeof(vsk->remote_addr)); sock->state =3D SS_CONNECTED; =20 /* sock map disallows redirection of non-TCP sockets with sk_state !=3D @@ -2487,7 +2527,7 @@ int vsock_core_register(const struct vsock_transport = *t, int features) =20 t_h2g =3D transport_h2g; t_g2h =3D transport_g2h; - t_dgram =3D transport_dgram; + t_dgram =3D transport_dgram_fallback; t_local =3D transport_local; =20 if (features & VSOCK_TRANSPORT_F_H2G) { @@ -2506,7 +2546,7 @@ int vsock_core_register(const struct vsock_transport = *t, int features) t_g2h =3D t; } =20 - if (features & VSOCK_TRANSPORT_F_DGRAM) { + if (features & VSOCK_TRANSPORT_F_DGRAM_FALLBACK) { if (t_dgram) { err =3D -EBUSY; goto err_busy; @@ -2524,7 +2564,7 @@ int vsock_core_register(const struct vsock_transport = *t, int features) =20 transport_h2g =3D t_h2g; transport_g2h =3D t_g2h; - transport_dgram =3D t_dgram; + transport_dgram_fallback =3D t_dgram; transport_local =3D t_local; =20 err_busy: @@ -2543,8 +2583,8 @@ void vsock_core_unregister(const struct vsock_transpo= rt *t) if (transport_g2h =3D=3D t) transport_g2h =3D NULL; =20 - if (transport_dgram =3D=3D t) - transport_dgram =3D NULL; + if (transport_dgram_fallback =3D=3D t) + transport_dgram_fallback =3D NULL; =20 if (transport_local =3D=3D t) transport_local =3D NULL; diff --git a/net/vmw_vsock/hyperv_transport.c b/net/vmw_vsock/hyperv_transp= ort.c index 7f1ea434656d..c29000f2612a 100644 --- a/net/vmw_vsock/hyperv_transport.c +++ b/net/vmw_vsock/hyperv_transport.c @@ -551,11 +551,6 @@ static void hvs_destruct(struct vsock_sock *vsk) kfree(hvs); } =20 -static int hvs_dgram_bind(struct vsock_sock *vsk, struct sockaddr_vm *addr) -{ - return -EOPNOTSUPP; -} - static int hvs_dgram_enqueue(struct vsock_sock *vsk, struct sockaddr_vm *remote, struct msghdr *msg, size_t dgram_len) @@ -826,7 +821,6 @@ static struct vsock_transport hvs_transport =3D { .connect =3D hvs_connect, .shutdown =3D hvs_shutdown, =20 - .dgram_bind =3D hvs_dgram_bind, .dgram_enqueue =3D hvs_dgram_enqueue, .dgram_allow =3D hvs_dgram_allow, =20 diff --git a/net/vmw_vsock/virtio_transport.c b/net/vmw_vsock/virtio_transp= ort.c index 66edffdbf303..ac2126c7dac5 100644 --- a/net/vmw_vsock/virtio_transport.c +++ b/net/vmw_vsock/virtio_transport.c @@ -428,7 +428,6 @@ static struct virtio_transport virtio_transport =3D { .shutdown =3D virtio_transport_shutdown, .cancel_pkt =3D virtio_transport_cancel_pkt, =20 - .dgram_bind =3D virtio_transport_dgram_bind, .dgram_enqueue =3D virtio_transport_dgram_enqueue, .dgram_allow =3D virtio_transport_dgram_allow, =20 diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio= _transport_common.c index 01ea1402ad40..ffcbdd77feaa 100644 --- a/net/vmw_vsock/virtio_transport_common.c +++ b/net/vmw_vsock/virtio_transport_common.c @@ -781,13 +781,6 @@ bool virtio_transport_stream_allow(u32 cid, u32 port) } EXPORT_SYMBOL_GPL(virtio_transport_stream_allow); =20 -int virtio_transport_dgram_bind(struct vsock_sock *vsk, - struct sockaddr_vm *addr) -{ - return -EOPNOTSUPP; -} -EXPORT_SYMBOL_GPL(virtio_transport_dgram_bind); - bool virtio_transport_dgram_allow(u32 cid, u32 port) { return false; diff --git a/net/vmw_vsock/vmci_transport.c b/net/vmw_vsock/vmci_transport.c index 0bbbdb222245..857b0461f856 100644 --- a/net/vmw_vsock/vmci_transport.c +++ b/net/vmw_vsock/vmci_transport.c @@ -2072,7 +2072,7 @@ static int __init vmci_transport_init(void) /* Register only with dgram feature, other features (H2G, G2H) will be * registered when the first host or guest becomes active. */ - err =3D vsock_core_register(&vmci_transport, VSOCK_TRANSPORT_F_DGRAM); + err =3D vsock_core_register(&vmci_transport, VSOCK_TRANSPORT_F_DGRAM_FALL= BACK); if (err < 0) goto err_unsubscribe; =20 diff --git a/net/vmw_vsock/vsock_loopback.c b/net/vmw_vsock/vsock_loopback.c index 2a59dd177c74..278235ea06c4 100644 --- a/net/vmw_vsock/vsock_loopback.c +++ b/net/vmw_vsock/vsock_loopback.c @@ -61,7 +61,6 @@ static struct virtio_transport loopback_transport =3D { .shutdown =3D virtio_transport_shutdown, .cancel_pkt =3D vsock_loopback_cancel_pkt, =20 - .dgram_bind =3D virtio_transport_dgram_bind, .dgram_enqueue =3D virtio_transport_dgram_enqueue, .dgram_allow =3D virtio_transport_dgram_allow, =20 --=20 2.30.2