| Message ID | 20230413-b4-vsock-dgram-v5-1-581bd37fdb26@bytedance.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | virtio/vsock: support datagrams | expand |
On 19.07.2023 03:50, Bobby Eshleman wrote: > This commit drops the transport->dgram_dequeue callback and makes > vsock_dgram_recvmsg() generic to all transports. > > To make this possible, two transport-level changes are introduced: > - implementation of the ->dgram_addr_init() callback to initialize > the sockaddr_vm structure with data from incoming socket buffers. > - transport implementations set the skb->data pointer to the beginning > of the payload prior to adding the skb to the socket's receive queue. > That is, they must use skb_pull() before enqueuing. This is an > agreement between the transport and the socket layer that skb->data > always points to the beginning of the payload (and not, for example, > the packet header). > > Signed-off-by: Bobby Eshleman <bobby.eshleman@bytedance.com> > --- > drivers/vhost/vsock.c | 1 - > include/linux/virtio_vsock.h | 5 --- > include/net/af_vsock.h | 3 +- > net/vmw_vsock/af_vsock.c | 40 ++++++++++++++++++++++- > net/vmw_vsock/hyperv_transport.c | 7 ---- > net/vmw_vsock/virtio_transport.c | 1 - > net/vmw_vsock/virtio_transport_common.c | 9 ----- > net/vmw_vsock/vmci_transport.c | 58 ++++++--------------------------- > net/vmw_vsock/vsock_loopback.c | 1 - > 9 files changed, 50 insertions(+), 75 deletions(-) > > diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c > index 6578db78f0ae..ae8891598a48 100644 > --- a/drivers/vhost/vsock.c > +++ b/drivers/vhost/vsock.c > @@ -410,7 +410,6 @@ 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, > > diff --git a/include/linux/virtio_vsock.h b/include/linux/virtio_vsock.h > index c58453699ee9..18cbe8d37fca 100644 > --- a/include/linux/virtio_vsock.h > +++ b/include/linux/virtio_vsock.h > @@ -167,11 +167,6 @@ virtio_transport_stream_dequeue(struct vsock_sock *vsk, > size_t len, > int type); > int > -virtio_transport_dgram_dequeue(struct vsock_sock *vsk, > - struct msghdr *msg, > - size_t len, int flags); > - > -int > virtio_transport_seqpacket_enqueue(struct vsock_sock *vsk, > struct msghdr *msg, > size_t len); > diff --git a/include/net/af_vsock.h b/include/net/af_vsock.h > index 0e7504a42925..305d57502e89 100644 > --- a/include/net/af_vsock.h > +++ b/include/net/af_vsock.h > @@ -120,11 +120,10 @@ 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); > + void (*dgram_addr_init)(struct sk_buff *skb, struct sockaddr_vm *addr); > > /* STREAM. */ > /* TODO: stream_bind() */ > diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c > index deb72a8c44a7..ad71e084bf2f 100644 > --- a/net/vmw_vsock/af_vsock.c > +++ b/net/vmw_vsock/af_vsock.c > @@ -1272,11 +1272,15 @@ 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); > @@ -1287,7 +1291,41 @@ 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; > + > + payload_len = skb->len; > + > + 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, 0, 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); > + > + transport->dgram_addr_init(skb, vm_addr); Do we need check that dgram_addr_init != NULL? because I see that not all transports have this callback set in this patch > + 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..7f1ea434656d 100644 > --- a/net/vmw_vsock/hyperv_transport.c > +++ b/net/vmw_vsock/hyperv_transport.c > @@ -556,12 +556,6 @@ 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) > -{ > - return -EOPNOTSUPP; > -} > - > static int hvs_dgram_enqueue(struct vsock_sock *vsk, > struct sockaddr_vm *remote, struct msghdr *msg, > size_t dgram_len) > @@ -833,7 +827,6 @@ static struct vsock_transport hvs_transport = { > .shutdown = hvs_shutdown, > > .dgram_bind = hvs_dgram_bind, > - .dgram_dequeue = hvs_dgram_dequeue, > .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..66edffdbf303 100644 > --- a/net/vmw_vsock/virtio_transport.c > +++ b/net/vmw_vsock/virtio_transport.c > @@ -429,7 +429,6 @@ 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, > > diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c > index b769fc258931..01ea1402ad40 100644 > --- a/net/vmw_vsock/virtio_transport_common.c > +++ b/net/vmw_vsock/virtio_transport_common.c > @@ -583,15 +583,6 @@ virtio_transport_seqpacket_enqueue(struct vsock_sock *vsk, > } > EXPORT_SYMBOL_GPL(virtio_transport_seqpacket_enqueue); > > -int > -virtio_transport_dgram_dequeue(struct vsock_sock *vsk, > - struct msghdr *msg, > - size_t len, int flags) > -{ > - return -EOPNOTSUPP; > -} > -EXPORT_SYMBOL_GPL(virtio_transport_dgram_dequeue); > - > s64 virtio_transport_stream_has_data(struct vsock_sock *vsk) > { > struct virtio_vsock_sock *vvs = vsk->trans; > diff --git a/net/vmw_vsock/vmci_transport.c b/net/vmw_vsock/vmci_transport.c > index b370070194fa..0bbbdb222245 100644 > --- a/net/vmw_vsock/vmci_transport.c > +++ b/net/vmw_vsock/vmci_transport.c > @@ -641,6 +641,7 @@ static int vmci_transport_recv_dgram_cb(void *data, struct vmci_datagram *dg) > sock_hold(sk); > skb_put(skb, size); > memcpy(skb->data, dg, size); > + skb_pull(skb, VMCI_DG_HEADERSIZE); > sk_receive_skb(sk, skb, 0); > > return VMCI_SUCCESS; > @@ -1731,57 +1732,18 @@ 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 void vmci_transport_dgram_addr_init(struct sk_buff *skb, > + struct sockaddr_vm *addr) > { > - int err; > struct vmci_datagram *dg; > - size_t payload_len; > - struct sk_buff *skb; > - > - if (flags & MSG_OOB || flags & MSG_ERRQUEUE) > - return -EOPNOTSUPP; > - > - /* 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; > - > - 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; > - } > - > - if (payload_len > len) { > - payload_len = len; > - msg->msg_flags |= MSG_TRUNC; > - } > + unsigned int cid, port; > > - /* Place the datagram payload in the user's iovec. */ > - err = skb_copy_datagram_msg(skb, sizeof(*dg), 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); > - vsock_addr_init(vm_addr, dg->src.context, dg->src.resource); > - msg->msg_namelen = sizeof(*vm_addr); > - } > - err = payload_len; > + WARN_ONCE(skb->head == skb->data, "vmci vsock bug: bad dgram skb"); > > -out: > - skb_free_datagram(&vsk->sk, skb); > - return err; > + dg = (struct vmci_datagram *)skb->head; > + cid = dg->src.context; > + port = dg->src.resource; > + vsock_addr_init(addr, cid, port); I think we 1) can short this to: vsock_addr_init(addr, dg->src.context, dg->src.resource); 2) w/o previous point, cid and port better be u32, as VMCI structure has u32 fields 'context' and 'resource' and 'vsock_addr_init()' also has u32 type for both arguments. Thanks, Arseniy > } > > static bool vmci_transport_dgram_allow(u32 cid, u32 port) > @@ -2040,9 +2002,9 @@ 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_addr_init = vmci_transport_dgram_addr_init, > .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..2a59dd177c74 100644 > --- a/net/vmw_vsock/vsock_loopback.c > +++ b/net/vmw_vsock/vsock_loopback.c > @@ -62,7 +62,6 @@ 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, > >
On Mon, Jul 24, 2023 at 09:11:44PM +0300, Arseniy Krasnov wrote: > > > On 19.07.2023 03:50, Bobby Eshleman wrote: > > This commit drops the transport->dgram_dequeue callback and makes > > vsock_dgram_recvmsg() generic to all transports. > > > > To make this possible, two transport-level changes are introduced: > > - implementation of the ->dgram_addr_init() callback to initialize > > the sockaddr_vm structure with data from incoming socket buffers. > > - transport implementations set the skb->data pointer to the beginning > > of the payload prior to adding the skb to the socket's receive queue. > > That is, they must use skb_pull() before enqueuing. This is an > > agreement between the transport and the socket layer that skb->data > > always points to the beginning of the payload (and not, for example, > > the packet header). > > > > Signed-off-by: Bobby Eshleman <bobby.eshleman@bytedance.com> > > --- > > drivers/vhost/vsock.c | 1 - > > include/linux/virtio_vsock.h | 5 --- > > include/net/af_vsock.h | 3 +- > > net/vmw_vsock/af_vsock.c | 40 ++++++++++++++++++++++- > > net/vmw_vsock/hyperv_transport.c | 7 ---- > > net/vmw_vsock/virtio_transport.c | 1 - > > net/vmw_vsock/virtio_transport_common.c | 9 ----- > > net/vmw_vsock/vmci_transport.c | 58 ++++++--------------------------- > > net/vmw_vsock/vsock_loopback.c | 1 - > > 9 files changed, 50 insertions(+), 75 deletions(-) > > > > diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c > > index 6578db78f0ae..ae8891598a48 100644 > > --- a/drivers/vhost/vsock.c > > +++ b/drivers/vhost/vsock.c > > @@ -410,7 +410,6 @@ 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, > > > > diff --git a/include/linux/virtio_vsock.h b/include/linux/virtio_vsock.h > > index c58453699ee9..18cbe8d37fca 100644 > > --- a/include/linux/virtio_vsock.h > > +++ b/include/linux/virtio_vsock.h > > @@ -167,11 +167,6 @@ virtio_transport_stream_dequeue(struct vsock_sock *vsk, > > size_t len, > > int type); > > int > > -virtio_transport_dgram_dequeue(struct vsock_sock *vsk, > > - struct msghdr *msg, > > - size_t len, int flags); > > - > > -int > > virtio_transport_seqpacket_enqueue(struct vsock_sock *vsk, > > struct msghdr *msg, > > size_t len); > > diff --git a/include/net/af_vsock.h b/include/net/af_vsock.h > > index 0e7504a42925..305d57502e89 100644 > > --- a/include/net/af_vsock.h > > +++ b/include/net/af_vsock.h > > @@ -120,11 +120,10 @@ 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); > > + void (*dgram_addr_init)(struct sk_buff *skb, struct sockaddr_vm *addr); > > > > /* STREAM. */ > > /* TODO: stream_bind() */ > > diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c > > index deb72a8c44a7..ad71e084bf2f 100644 > > --- a/net/vmw_vsock/af_vsock.c > > +++ b/net/vmw_vsock/af_vsock.c > > @@ -1272,11 +1272,15 @@ 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); > > @@ -1287,7 +1291,41 @@ 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; > > + > > + payload_len = skb->len; > > + > > + 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, 0, 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); > > + > > + transport->dgram_addr_init(skb, vm_addr); > > Do we need check that dgram_addr_init != NULL? because I see that not all transports have this > callback set in this patch > How about adding the check somewhere outside of the hotpath, such as when the transport is assigned? > > + 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..7f1ea434656d 100644 > > --- a/net/vmw_vsock/hyperv_transport.c > > +++ b/net/vmw_vsock/hyperv_transport.c > > @@ -556,12 +556,6 @@ 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) > > -{ > > - return -EOPNOTSUPP; > > -} > > - > > static int hvs_dgram_enqueue(struct vsock_sock *vsk, > > struct sockaddr_vm *remote, struct msghdr *msg, > > size_t dgram_len) > > @@ -833,7 +827,6 @@ static struct vsock_transport hvs_transport = { > > .shutdown = hvs_shutdown, > > > > .dgram_bind = hvs_dgram_bind, > > - .dgram_dequeue = hvs_dgram_dequeue, > > .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..66edffdbf303 100644 > > --- a/net/vmw_vsock/virtio_transport.c > > +++ b/net/vmw_vsock/virtio_transport.c > > @@ -429,7 +429,6 @@ 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, > > > > diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c > > index b769fc258931..01ea1402ad40 100644 > > --- a/net/vmw_vsock/virtio_transport_common.c > > +++ b/net/vmw_vsock/virtio_transport_common.c > > @@ -583,15 +583,6 @@ virtio_transport_seqpacket_enqueue(struct vsock_sock *vsk, > > } > > EXPORT_SYMBOL_GPL(virtio_transport_seqpacket_enqueue); > > > > -int > > -virtio_transport_dgram_dequeue(struct vsock_sock *vsk, > > - struct msghdr *msg, > > - size_t len, int flags) > > -{ > > - return -EOPNOTSUPP; > > -} > > -EXPORT_SYMBOL_GPL(virtio_transport_dgram_dequeue); > > - > > s64 virtio_transport_stream_has_data(struct vsock_sock *vsk) > > { > > struct virtio_vsock_sock *vvs = vsk->trans; > > diff --git a/net/vmw_vsock/vmci_transport.c b/net/vmw_vsock/vmci_transport.c > > index b370070194fa..0bbbdb222245 100644 > > --- a/net/vmw_vsock/vmci_transport.c > > +++ b/net/vmw_vsock/vmci_transport.c > > @@ -641,6 +641,7 @@ static int vmci_transport_recv_dgram_cb(void *data, struct vmci_datagram *dg) > > sock_hold(sk); > > skb_put(skb, size); > > memcpy(skb->data, dg, size); > > + skb_pull(skb, VMCI_DG_HEADERSIZE); > > sk_receive_skb(sk, skb, 0); > > > > return VMCI_SUCCESS; > > @@ -1731,57 +1732,18 @@ 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 void vmci_transport_dgram_addr_init(struct sk_buff *skb, > > + struct sockaddr_vm *addr) > > { > > - int err; > > struct vmci_datagram *dg; > > - size_t payload_len; > > - struct sk_buff *skb; > > - > > - if (flags & MSG_OOB || flags & MSG_ERRQUEUE) > > - return -EOPNOTSUPP; > > - > > - /* 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; > > - > > - 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; > > - } > > - > > - if (payload_len > len) { > > - payload_len = len; > > - msg->msg_flags |= MSG_TRUNC; > > - } > > + unsigned int cid, port; > > > > - /* Place the datagram payload in the user's iovec. */ > > - err = skb_copy_datagram_msg(skb, sizeof(*dg), 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); > > - vsock_addr_init(vm_addr, dg->src.context, dg->src.resource); > > - msg->msg_namelen = sizeof(*vm_addr); > > - } > > - err = payload_len; > > + WARN_ONCE(skb->head == skb->data, "vmci vsock bug: bad dgram skb"); > > > > -out: > > - skb_free_datagram(&vsk->sk, skb); > > - return err; > > + dg = (struct vmci_datagram *)skb->head; > > + cid = dg->src.context; > > + port = dg->src.resource; > > + vsock_addr_init(addr, cid, port); > > I think we > > 1) can short this to: > > vsock_addr_init(addr, dg->src.context, dg->src.resource); > > 2) w/o previous point, cid and port better be u32, as VMCI structure has u32 fields 'context' and > 'resource' and 'vsock_addr_init()' also has u32 type for both arguments. > > Thanks, Arseniy Sounds good, thanks. > > > } > > > > static bool vmci_transport_dgram_allow(u32 cid, u32 port) > > @@ -2040,9 +2002,9 @@ 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_addr_init = vmci_transport_dgram_addr_init, > > .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..2a59dd177c74 100644 > > --- a/net/vmw_vsock/vsock_loopback.c > > +++ b/net/vmw_vsock/vsock_loopback.c > > @@ -62,7 +62,6 @@ 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, > > > > Thanks, Bobby
On 26.07.2023 21:21, Bobby Eshleman wrote: > On Mon, Jul 24, 2023 at 09:11:44PM +0300, Arseniy Krasnov wrote: >> >> >> On 19.07.2023 03:50, Bobby Eshleman wrote: >>> This commit drops the transport->dgram_dequeue callback and makes >>> vsock_dgram_recvmsg() generic to all transports. >>> >>> To make this possible, two transport-level changes are introduced: >>> - implementation of the ->dgram_addr_init() callback to initialize >>> the sockaddr_vm structure with data from incoming socket buffers. >>> - transport implementations set the skb->data pointer to the beginning >>> of the payload prior to adding the skb to the socket's receive queue. >>> That is, they must use skb_pull() before enqueuing. This is an >>> agreement between the transport and the socket layer that skb->data >>> always points to the beginning of the payload (and not, for example, >>> the packet header). >>> >>> Signed-off-by: Bobby Eshleman <bobby.eshleman@bytedance.com> >>> --- >>> drivers/vhost/vsock.c | 1 - >>> include/linux/virtio_vsock.h | 5 --- >>> include/net/af_vsock.h | 3 +- >>> net/vmw_vsock/af_vsock.c | 40 ++++++++++++++++++++++- >>> net/vmw_vsock/hyperv_transport.c | 7 ---- >>> net/vmw_vsock/virtio_transport.c | 1 - >>> net/vmw_vsock/virtio_transport_common.c | 9 ----- >>> net/vmw_vsock/vmci_transport.c | 58 ++++++--------------------------- >>> net/vmw_vsock/vsock_loopback.c | 1 - >>> 9 files changed, 50 insertions(+), 75 deletions(-) >>> >>> diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c >>> index 6578db78f0ae..ae8891598a48 100644 >>> --- a/drivers/vhost/vsock.c >>> +++ b/drivers/vhost/vsock.c >>> @@ -410,7 +410,6 @@ 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, >>> >>> diff --git a/include/linux/virtio_vsock.h b/include/linux/virtio_vsock.h >>> index c58453699ee9..18cbe8d37fca 100644 >>> --- a/include/linux/virtio_vsock.h >>> +++ b/include/linux/virtio_vsock.h >>> @@ -167,11 +167,6 @@ virtio_transport_stream_dequeue(struct vsock_sock *vsk, >>> size_t len, >>> int type); >>> int >>> -virtio_transport_dgram_dequeue(struct vsock_sock *vsk, >>> - struct msghdr *msg, >>> - size_t len, int flags); >>> - >>> -int >>> virtio_transport_seqpacket_enqueue(struct vsock_sock *vsk, >>> struct msghdr *msg, >>> size_t len); >>> diff --git a/include/net/af_vsock.h b/include/net/af_vsock.h >>> index 0e7504a42925..305d57502e89 100644 >>> --- a/include/net/af_vsock.h >>> +++ b/include/net/af_vsock.h >>> @@ -120,11 +120,10 @@ 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); >>> + void (*dgram_addr_init)(struct sk_buff *skb, struct sockaddr_vm *addr); >>> >>> /* STREAM. */ >>> /* TODO: stream_bind() */ >>> diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c >>> index deb72a8c44a7..ad71e084bf2f 100644 >>> --- a/net/vmw_vsock/af_vsock.c >>> +++ b/net/vmw_vsock/af_vsock.c >>> @@ -1272,11 +1272,15 @@ 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); >>> @@ -1287,7 +1291,41 @@ 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; >>> + >>> + payload_len = skb->len; >>> + >>> + 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, 0, 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); >>> + >>> + transport->dgram_addr_init(skb, vm_addr); >> >> Do we need check that dgram_addr_init != NULL? because I see that not all transports have this >> callback set in this patch >> > > How about adding the check somewhere outside of the hotpath, such as > when the transport is assigned? Yes, may be we can return ESOCKTNOSUPPORT if this callback is not provided by transport (as we dereference it here without any checks). Thanks, Arseniy > >>> + 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..7f1ea434656d 100644 >>> --- a/net/vmw_vsock/hyperv_transport.c >>> +++ b/net/vmw_vsock/hyperv_transport.c >>> @@ -556,12 +556,6 @@ 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) >>> -{ >>> - return -EOPNOTSUPP; >>> -} >>> - >>> static int hvs_dgram_enqueue(struct vsock_sock *vsk, >>> struct sockaddr_vm *remote, struct msghdr *msg, >>> size_t dgram_len) >>> @@ -833,7 +827,6 @@ static struct vsock_transport hvs_transport = { >>> .shutdown = hvs_shutdown, >>> >>> .dgram_bind = hvs_dgram_bind, >>> - .dgram_dequeue = hvs_dgram_dequeue, >>> .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..66edffdbf303 100644 >>> --- a/net/vmw_vsock/virtio_transport.c >>> +++ b/net/vmw_vsock/virtio_transport.c >>> @@ -429,7 +429,6 @@ 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, >>> >>> diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c >>> index b769fc258931..01ea1402ad40 100644 >>> --- a/net/vmw_vsock/virtio_transport_common.c >>> +++ b/net/vmw_vsock/virtio_transport_common.c >>> @@ -583,15 +583,6 @@ virtio_transport_seqpacket_enqueue(struct vsock_sock *vsk, >>> } >>> EXPORT_SYMBOL_GPL(virtio_transport_seqpacket_enqueue); >>> >>> -int >>> -virtio_transport_dgram_dequeue(struct vsock_sock *vsk, >>> - struct msghdr *msg, >>> - size_t len, int flags) >>> -{ >>> - return -EOPNOTSUPP; >>> -} >>> -EXPORT_SYMBOL_GPL(virtio_transport_dgram_dequeue); >>> - >>> s64 virtio_transport_stream_has_data(struct vsock_sock *vsk) >>> { >>> struct virtio_vsock_sock *vvs = vsk->trans; >>> diff --git a/net/vmw_vsock/vmci_transport.c b/net/vmw_vsock/vmci_transport.c >>> index b370070194fa..0bbbdb222245 100644 >>> --- a/net/vmw_vsock/vmci_transport.c >>> +++ b/net/vmw_vsock/vmci_transport.c >>> @@ -641,6 +641,7 @@ static int vmci_transport_recv_dgram_cb(void *data, struct vmci_datagram *dg) >>> sock_hold(sk); >>> skb_put(skb, size); >>> memcpy(skb->data, dg, size); >>> + skb_pull(skb, VMCI_DG_HEADERSIZE); >>> sk_receive_skb(sk, skb, 0); >>> >>> return VMCI_SUCCESS; >>> @@ -1731,57 +1732,18 @@ 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 void vmci_transport_dgram_addr_init(struct sk_buff *skb, >>> + struct sockaddr_vm *addr) >>> { >>> - int err; >>> struct vmci_datagram *dg; >>> - size_t payload_len; >>> - struct sk_buff *skb; >>> - >>> - if (flags & MSG_OOB || flags & MSG_ERRQUEUE) >>> - return -EOPNOTSUPP; >>> - >>> - /* 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; >>> - >>> - 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; >>> - } >>> - >>> - if (payload_len > len) { >>> - payload_len = len; >>> - msg->msg_flags |= MSG_TRUNC; >>> - } >>> + unsigned int cid, port; >>> >>> - /* Place the datagram payload in the user's iovec. */ >>> - err = skb_copy_datagram_msg(skb, sizeof(*dg), 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); >>> - vsock_addr_init(vm_addr, dg->src.context, dg->src.resource); >>> - msg->msg_namelen = sizeof(*vm_addr); >>> - } >>> - err = payload_len; >>> + WARN_ONCE(skb->head == skb->data, "vmci vsock bug: bad dgram skb"); >>> >>> -out: >>> - skb_free_datagram(&vsk->sk, skb); >>> - return err; >>> + dg = (struct vmci_datagram *)skb->head; >>> + cid = dg->src.context; >>> + port = dg->src.resource; >>> + vsock_addr_init(addr, cid, port); >> >> I think we >> >> 1) can short this to: >> >> vsock_addr_init(addr, dg->src.context, dg->src.resource); >> >> 2) w/o previous point, cid and port better be u32, as VMCI structure has u32 fields 'context' and >> 'resource' and 'vsock_addr_init()' also has u32 type for both arguments. >> >> Thanks, Arseniy > > Sounds good, thanks. > >> >>> } >>> >>> static bool vmci_transport_dgram_allow(u32 cid, u32 port) >>> @@ -2040,9 +2002,9 @@ 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_addr_init = vmci_transport_dgram_addr_init, >>> .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..2a59dd177c74 100644 >>> --- a/net/vmw_vsock/vsock_loopback.c >>> +++ b/net/vmw_vsock/vsock_loopback.c >>> @@ -62,7 +62,6 @@ 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, >>> >>> > > Thanks, > Bobby
diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c index 6578db78f0ae..ae8891598a48 100644 --- a/drivers/vhost/vsock.c +++ b/drivers/vhost/vsock.c @@ -410,7 +410,6 @@ 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, diff --git a/include/linux/virtio_vsock.h b/include/linux/virtio_vsock.h index c58453699ee9..18cbe8d37fca 100644 --- a/include/linux/virtio_vsock.h +++ b/include/linux/virtio_vsock.h @@ -167,11 +167,6 @@ virtio_transport_stream_dequeue(struct vsock_sock *vsk, size_t len, int type); int -virtio_transport_dgram_dequeue(struct vsock_sock *vsk, - struct msghdr *msg, - size_t len, int flags); - -int virtio_transport_seqpacket_enqueue(struct vsock_sock *vsk, struct msghdr *msg, size_t len); diff --git a/include/net/af_vsock.h b/include/net/af_vsock.h index 0e7504a42925..305d57502e89 100644 --- a/include/net/af_vsock.h +++ b/include/net/af_vsock.h @@ -120,11 +120,10 @@ 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); + void (*dgram_addr_init)(struct sk_buff *skb, struct sockaddr_vm *addr); /* STREAM. */ /* TODO: stream_bind() */ diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c index deb72a8c44a7..ad71e084bf2f 100644 --- a/net/vmw_vsock/af_vsock.c +++ b/net/vmw_vsock/af_vsock.c @@ -1272,11 +1272,15 @@ 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); @@ -1287,7 +1291,41 @@ 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; + + payload_len = skb->len; + + 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, 0, 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); + + transport->dgram_addr_init(skb, vm_addr); + 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..7f1ea434656d 100644 --- a/net/vmw_vsock/hyperv_transport.c +++ b/net/vmw_vsock/hyperv_transport.c @@ -556,12 +556,6 @@ 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) -{ - return -EOPNOTSUPP; -} - static int hvs_dgram_enqueue(struct vsock_sock *vsk, struct sockaddr_vm *remote, struct msghdr *msg, size_t dgram_len) @@ -833,7 +827,6 @@ static struct vsock_transport hvs_transport = { .shutdown = hvs_shutdown, .dgram_bind = hvs_dgram_bind, - .dgram_dequeue = hvs_dgram_dequeue, .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..66edffdbf303 100644 --- a/net/vmw_vsock/virtio_transport.c +++ b/net/vmw_vsock/virtio_transport.c @@ -429,7 +429,6 @@ 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, diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c index b769fc258931..01ea1402ad40 100644 --- a/net/vmw_vsock/virtio_transport_common.c +++ b/net/vmw_vsock/virtio_transport_common.c @@ -583,15 +583,6 @@ virtio_transport_seqpacket_enqueue(struct vsock_sock *vsk, } EXPORT_SYMBOL_GPL(virtio_transport_seqpacket_enqueue); -int -virtio_transport_dgram_dequeue(struct vsock_sock *vsk, - struct msghdr *msg, - size_t len, int flags) -{ - return -EOPNOTSUPP; -} -EXPORT_SYMBOL_GPL(virtio_transport_dgram_dequeue); - s64 virtio_transport_stream_has_data(struct vsock_sock *vsk) { struct virtio_vsock_sock *vvs = vsk->trans; diff --git a/net/vmw_vsock/vmci_transport.c b/net/vmw_vsock/vmci_transport.c index b370070194fa..0bbbdb222245 100644 --- a/net/vmw_vsock/vmci_transport.c +++ b/net/vmw_vsock/vmci_transport.c @@ -641,6 +641,7 @@ static int vmci_transport_recv_dgram_cb(void *data, struct vmci_datagram *dg) sock_hold(sk); skb_put(skb, size); memcpy(skb->data, dg, size); + skb_pull(skb, VMCI_DG_HEADERSIZE); sk_receive_skb(sk, skb, 0); return VMCI_SUCCESS; @@ -1731,57 +1732,18 @@ 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 void vmci_transport_dgram_addr_init(struct sk_buff *skb, + struct sockaddr_vm *addr) { - int err; struct vmci_datagram *dg; - size_t payload_len; - struct sk_buff *skb; - - if (flags & MSG_OOB || flags & MSG_ERRQUEUE) - return -EOPNOTSUPP; - - /* 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; - - 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; - } - - if (payload_len > len) { - payload_len = len; - msg->msg_flags |= MSG_TRUNC; - } + unsigned int cid, port; - /* Place the datagram payload in the user's iovec. */ - err = skb_copy_datagram_msg(skb, sizeof(*dg), 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); - vsock_addr_init(vm_addr, dg->src.context, dg->src.resource); - msg->msg_namelen = sizeof(*vm_addr); - } - err = payload_len; + WARN_ONCE(skb->head == skb->data, "vmci vsock bug: bad dgram skb"); -out: - skb_free_datagram(&vsk->sk, skb); - return err; + dg = (struct vmci_datagram *)skb->head; + cid = dg->src.context; + port = dg->src.resource; + vsock_addr_init(addr, cid, port); } static bool vmci_transport_dgram_allow(u32 cid, u32 port) @@ -2040,9 +2002,9 @@ 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_addr_init = vmci_transport_dgram_addr_init, .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..2a59dd177c74 100644 --- a/net/vmw_vsock/vsock_loopback.c +++ b/net/vmw_vsock/vsock_loopback.c @@ -62,7 +62,6 @@ 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,
This commit drops the transport->dgram_dequeue callback and makes vsock_dgram_recvmsg() generic to all transports. To make this possible, two transport-level changes are introduced: - implementation of the ->dgram_addr_init() callback to initialize the sockaddr_vm structure with data from incoming socket buffers. - transport implementations set the skb->data pointer to the beginning of the payload prior to adding the skb to the socket's receive queue. That is, they must use skb_pull() before enqueuing. This is an agreement between the transport and the socket layer that skb->data always points to the beginning of the payload (and not, for example, the packet header). Signed-off-by: Bobby Eshleman <bobby.eshleman@bytedance.com> --- drivers/vhost/vsock.c | 1 - include/linux/virtio_vsock.h | 5 --- include/net/af_vsock.h | 3 +- net/vmw_vsock/af_vsock.c | 40 ++++++++++++++++++++++- net/vmw_vsock/hyperv_transport.c | 7 ---- net/vmw_vsock/virtio_transport.c | 1 - net/vmw_vsock/virtio_transport_common.c | 9 ----- net/vmw_vsock/vmci_transport.c | 58 ++++++--------------------------- net/vmw_vsock/vsock_loopback.c | 1 - 9 files changed, 50 insertions(+), 75 deletions(-)