[PATCH RFC net-next v4 1/8] vsock/dgram: generalize recvmsg and drop transport->dgram_dequeue
From: Bobby Eshleman <hidden>
Date: 2023-06-10 00:59:27
Also in:
bpf, kvm, linux-hyperv, lkml
Subsystem:
hyper-v/azure core and drivers, networking [general], the rest, virtio and vhost vsock driver, virtio core, virtio host (vhost), vm sockets (af_vsock), vmware vsock vmci transport driver · Maintainers:
"K. Y. Srinivasan", Haiyang Zhang, Wei Liu, Dexuan Cui, Long Li, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds, Stefan Hajnoczi, Stefano Garzarella, "Michael S. Tsirkin", Jason Wang, Bryan Tan, Vishnu Dasa
This commit drops the transport->dgram_dequeue callback and makes vsock_dgram_recvmsg() generic. It also adds additional transport callbacks for use by the generic vsock_dgram_recvmsg(), such as for parsing skbs for CID/port which vary in format per transport. Signed-off-by: Bobby Eshleman <redacted> --- drivers/vhost/vsock.c | 4 +- include/linux/virtio_vsock.h | 3 ++ include/net/af_vsock.h | 13 ++++++- net/vmw_vsock/af_vsock.c | 51 ++++++++++++++++++++++++- net/vmw_vsock/hyperv_transport.c | 17 +++++++-- net/vmw_vsock/virtio_transport.c | 4 +- net/vmw_vsock/virtio_transport_common.c | 18 +++++++++ net/vmw_vsock/vmci_transport.c | 68 +++++++++++++-------------------- net/vmw_vsock/vsock_loopback.c | 4 +- 9 files changed, 132 insertions(+), 50 deletions(-)
diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c
index 6578db78f0ae..c8201c070b4b 100644
--- a/drivers/vhost/vsock.c
+++ b/drivers/vhost/vsock.c@@ -410,9 +410,11 @@ static struct virtio_transport vhost_transport = { .cancel_pkt = vhost_transport_cancel_pkt, .dgram_enqueue = virtio_transport_dgram_enqueue, - .dgram_dequeue = virtio_transport_dgram_dequeue, .dgram_bind = virtio_transport_dgram_bind, .dgram_allow = virtio_transport_dgram_allow, + .dgram_get_cid = virtio_transport_dgram_get_cid, + .dgram_get_port = virtio_transport_dgram_get_port, + .dgram_get_length = virtio_transport_dgram_get_length, .stream_enqueue = virtio_transport_stream_enqueue, .stream_dequeue = virtio_transport_stream_dequeue,
diff --git a/include/linux/virtio_vsock.h b/include/linux/virtio_vsock.h
index c58453699ee9..23521a318cf0 100644
--- a/include/linux/virtio_vsock.h
+++ b/include/linux/virtio_vsock.h@@ -219,6 +219,9 @@ 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); +int virtio_transport_dgram_get_cid(struct sk_buff *skb, unsigned int *cid); +int virtio_transport_dgram_get_port(struct sk_buff *skb, unsigned int *port); +int virtio_transport_dgram_get_length(struct sk_buff *skb, size_t *len); int virtio_transport_connect(struct vsock_sock *vsk);
diff --git a/include/net/af_vsock.h b/include/net/af_vsock.h
index 0e7504a42925..7bedb9ee7e3e 100644
--- a/include/net/af_vsock.h
+++ b/include/net/af_vsock.h@@ -120,11 +120,20 @@ struct vsock_transport { /* DGRAM. */ int (*dgram_bind)(struct vsock_sock *, struct sockaddr_vm *); - int (*dgram_dequeue)(struct vsock_sock *vsk, struct msghdr *msg, - size_t len, int flags); int (*dgram_enqueue)(struct vsock_sock *, struct sockaddr_vm *, struct msghdr *, size_t len); bool (*dgram_allow)(u32 cid, u32 port); + int (*dgram_get_cid)(struct sk_buff *skb, unsigned int *cid); + int (*dgram_get_port)(struct sk_buff *skb, unsigned int *port); + int (*dgram_get_length)(struct sk_buff *skb, size_t *length); + + /* The number of bytes into the buffer at which the payload starts, as + * first seen by the receiving socket layer. For example, if the + * transport presets the skb pointers using skb_pull(sizeof(header)) + * than this would be zero, otherwise it would be the size of the + * header. + */ + const size_t dgram_payload_offset; /* STREAM. */ /* TODO: stream_bind() */
diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index efb8a0937a13..ffb4dd8b6ea7 100644
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c@@ -1271,11 +1271,15 @@ static int vsock_dgram_connect(struct socket *sock, int vsock_dgram_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, int flags) { + const struct vsock_transport *transport; #ifdef CONFIG_BPF_SYSCALL const struct proto *prot; #endif struct vsock_sock *vsk; + struct sk_buff *skb; + size_t payload_len; struct sock *sk; + int err; sk = sock->sk; vsk = vsock_sk(sk);
@@ -1286,7 +1290,52 @@ int vsock_dgram_recvmsg(struct socket *sock, struct msghdr *msg, return prot->recvmsg(sk, msg, len, flags, NULL); #endif - return vsk->transport->dgram_dequeue(vsk, msg, len, flags); + if (flags & MSG_OOB || flags & MSG_ERRQUEUE) + return -EOPNOTSUPP; + + transport = vsk->transport; + + /* Retrieve the head sk_buff from the socket's receive queue. */ + err = 0; + skb = skb_recv_datagram(sk_vsock(vsk), flags, &err); + if (!skb) + return err; + + err = transport->dgram_get_length(skb, &payload_len); + if (err) + goto out; + + if (payload_len > len) { + payload_len = len; + msg->msg_flags |= MSG_TRUNC; + } + + /* Place the datagram payload in the user's iovec. */ + err = skb_copy_datagram_msg(skb, transport->dgram_payload_offset, msg, payload_len); + if (err) + goto out; + + if (msg->msg_name) { + /* Provide the address of the sender. */ + DECLARE_SOCKADDR(struct sockaddr_vm *, vm_addr, msg->msg_name); + unsigned int cid, port; + + err = transport->dgram_get_cid(skb, &cid); + if (err) + goto out; + + err = transport->dgram_get_port(skb, &port); + if (err) + goto out; + + vsock_addr_init(vm_addr, cid, port); + msg->msg_namelen = sizeof(*vm_addr); + } + err = payload_len; + +out: + skb_free_datagram(&vsk->sk, skb); + return err; } EXPORT_SYMBOL_GPL(vsock_dgram_recvmsg);
diff --git a/net/vmw_vsock/hyperv_transport.c b/net/vmw_vsock/hyperv_transport.c
index 7cb1a9d2cdb4..ff6e87e25fa0 100644
--- a/net/vmw_vsock/hyperv_transport.c
+++ b/net/vmw_vsock/hyperv_transport.c@@ -556,8 +556,17 @@ static int hvs_dgram_bind(struct vsock_sock *vsk, struct sockaddr_vm *addr) return -EOPNOTSUPP; } -static int hvs_dgram_dequeue(struct vsock_sock *vsk, struct msghdr *msg, - size_t len, int flags) +static int hvs_dgram_get_cid(struct sk_buff *skb, unsigned int *cid) +{ + return -EOPNOTSUPP; +} + +static int hvs_dgram_get_port(struct sk_buff *skb, unsigned int *port) +{ + return -EOPNOTSUPP; +} + +static int hvs_dgram_get_length(struct sk_buff *skb, size_t *len) { return -EOPNOTSUPP; }
@@ -833,7 +842,9 @@ static struct vsock_transport hvs_transport = { .shutdown = hvs_shutdown, .dgram_bind = hvs_dgram_bind, - .dgram_dequeue = hvs_dgram_dequeue, + .dgram_get_cid = hvs_dgram_get_cid, + .dgram_get_port = hvs_dgram_get_port, + .dgram_get_length = hvs_dgram_get_length, .dgram_enqueue = hvs_dgram_enqueue, .dgram_allow = hvs_dgram_allow,
diff --git a/net/vmw_vsock/virtio_transport.c b/net/vmw_vsock/virtio_transport.c
index e95df847176b..5763cdf13804 100644
--- a/net/vmw_vsock/virtio_transport.c
+++ b/net/vmw_vsock/virtio_transport.c@@ -429,9 +429,11 @@ static struct virtio_transport virtio_transport = { .cancel_pkt = virtio_transport_cancel_pkt, .dgram_bind = virtio_transport_dgram_bind, - .dgram_dequeue = virtio_transport_dgram_dequeue, .dgram_enqueue = virtio_transport_dgram_enqueue, .dgram_allow = virtio_transport_dgram_allow, + .dgram_get_cid = virtio_transport_dgram_get_cid, + .dgram_get_port = virtio_transport_dgram_get_port, + .dgram_get_length = virtio_transport_dgram_get_length, .stream_dequeue = virtio_transport_stream_dequeue, .stream_enqueue = virtio_transport_stream_enqueue,
diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c
index b769fc258931..e6903c719964 100644
--- a/net/vmw_vsock/virtio_transport_common.c
+++ b/net/vmw_vsock/virtio_transport_common.c@@ -797,6 +797,24 @@ int virtio_transport_dgram_bind(struct vsock_sock *vsk, } EXPORT_SYMBOL_GPL(virtio_transport_dgram_bind); +int virtio_transport_dgram_get_cid(struct sk_buff *skb, unsigned int *cid) +{ + return -EOPNOTSUPP; +} +EXPORT_SYMBOL_GPL(virtio_transport_dgram_get_cid); + +int virtio_transport_dgram_get_port(struct sk_buff *skb, unsigned int *port) +{ + return -EOPNOTSUPP; +} +EXPORT_SYMBOL_GPL(virtio_transport_dgram_get_port); + +int virtio_transport_dgram_get_length(struct sk_buff *skb, size_t *len) +{ + return -EOPNOTSUPP; +} +EXPORT_SYMBOL_GPL(virtio_transport_dgram_get_length); + 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 b370070194fa..bbc63826bf48 100644
--- a/net/vmw_vsock/vmci_transport.c
+++ b/net/vmw_vsock/vmci_transport.c@@ -1731,57 +1731,40 @@ static int vmci_transport_dgram_enqueue( return err - sizeof(*dg); } -static int vmci_transport_dgram_dequeue(struct vsock_sock *vsk, - struct msghdr *msg, size_t len, - int flags) +static int vmci_transport_dgram_get_cid(struct sk_buff *skb, unsigned int *cid) { - int err; struct vmci_datagram *dg; - size_t payload_len; - struct sk_buff *skb; - if (flags & MSG_OOB || flags & MSG_ERRQUEUE) - return -EOPNOTSUPP; + dg = (struct vmci_datagram *)skb->data; + if (!dg) + return -EINVAL; - /* Retrieve the head sk_buff from the socket's receive queue. */ - err = 0; - skb = skb_recv_datagram(&vsk->sk, flags, &err); - if (!skb) - return err; + *cid = dg->src.context; + return 0; +} + +static int vmci_transport_dgram_get_port(struct sk_buff *skb, unsigned int *port) +{ + struct vmci_datagram *dg; dg = (struct vmci_datagram *)skb->data; if (!dg) - /* err is 0, meaning we read zero bytes. */ - goto out; - - payload_len = dg->payload_size; - /* Ensure the sk_buff matches the payload size claimed in the packet. */ - if (payload_len != skb->len - sizeof(*dg)) { - err = -EINVAL; - goto out; - } + return -EINVAL; - if (payload_len > len) { - payload_len = len; - msg->msg_flags |= MSG_TRUNC; - } + *port = dg->src.resource; + return 0; +} - /* Place the datagram payload in the user's iovec. */ - err = skb_copy_datagram_msg(skb, sizeof(*dg), msg, payload_len); - if (err) - goto out; +static int vmci_transport_dgram_get_length(struct sk_buff *skb, size_t *len) +{ + struct vmci_datagram *dg; - if (msg->msg_name) { - /* Provide the address of the sender. */ - DECLARE_SOCKADDR(struct sockaddr_vm *, vm_addr, msg->msg_name); - vsock_addr_init(vm_addr, dg->src.context, dg->src.resource); - msg->msg_namelen = sizeof(*vm_addr); - } - err = payload_len; + dg = (struct vmci_datagram *)skb->data; + if (!dg) + return -EINVAL; -out: - skb_free_datagram(&vsk->sk, skb); - return err; + *len = dg->payload_size; + return 0; } static bool vmci_transport_dgram_allow(u32 cid, u32 port)
@@ -2040,9 +2023,12 @@ static struct vsock_transport vmci_transport = { .release = vmci_transport_release, .connect = vmci_transport_connect, .dgram_bind = vmci_transport_dgram_bind, - .dgram_dequeue = vmci_transport_dgram_dequeue, .dgram_enqueue = vmci_transport_dgram_enqueue, .dgram_allow = vmci_transport_dgram_allow, + .dgram_get_cid = vmci_transport_dgram_get_cid, + .dgram_get_port = vmci_transport_dgram_get_port, + .dgram_get_length = vmci_transport_dgram_get_length, + .dgram_payload_offset = sizeof(struct vmci_datagram), .stream_dequeue = vmci_transport_stream_dequeue, .stream_enqueue = vmci_transport_stream_enqueue, .stream_has_data = vmci_transport_stream_has_data,
diff --git a/net/vmw_vsock/vsock_loopback.c b/net/vmw_vsock/vsock_loopback.c
index 5c6360df1f31..2f3cabc79ee5 100644
--- a/net/vmw_vsock/vsock_loopback.c
+++ b/net/vmw_vsock/vsock_loopback.c@@ -62,9 +62,11 @@ static struct virtio_transport loopback_transport = { .cancel_pkt = vsock_loopback_cancel_pkt, .dgram_bind = virtio_transport_dgram_bind, - .dgram_dequeue = virtio_transport_dgram_dequeue, .dgram_enqueue = virtio_transport_dgram_enqueue, .dgram_allow = virtio_transport_dgram_allow, + .dgram_get_cid = virtio_transport_dgram_get_cid, + .dgram_get_port = virtio_transport_dgram_get_port, + .dgram_get_length = virtio_transport_dgram_get_length, .stream_dequeue = virtio_transport_stream_dequeue, .stream_enqueue = virtio_transport_stream_enqueue,
--
2.30.2