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authorBobby Eshleman <bobby.eshleman@bytedance.com>2023-03-27 22:11:51 +0300
committerDavid S. Miller <davem@davemloft.net>2023-03-29 10:19:38 +0300
commit634f1a7110b439c65fd8a809171c1d2d28bcea6f (patch)
treec177884c45da08c7552518f7215d1d6555dc2863 /net/vmw_vsock
parent24265c2c91ad6aae9446e18472566cd83e92b602 (diff)
downloadlinux-634f1a7110b439c65fd8a809171c1d2d28bcea6f.tar.xz
vsock: support sockmap
This patch adds sockmap support for vsock sockets. It is intended to be usable by all transports, but only the virtio and loopback transports are implemented. SOCK_STREAM, SOCK_DGRAM, and SOCK_SEQPACKET are all supported. Signed-off-by: Bobby Eshleman <bobby.eshleman@bytedance.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/vmw_vsock')
-rw-r--r--net/vmw_vsock/Makefile1
-rw-r--r--net/vmw_vsock/af_vsock.c64
-rw-r--r--net/vmw_vsock/virtio_transport.c2
-rw-r--r--net/vmw_vsock/virtio_transport_common.c25
-rw-r--r--net/vmw_vsock/vsock_bpf.c174
-rw-r--r--net/vmw_vsock/vsock_loopback.c2
6 files changed, 262 insertions, 6 deletions
diff --git a/net/vmw_vsock/Makefile b/net/vmw_vsock/Makefile
index 6a943ec95c4a..5da74c4a9f1d 100644
--- a/net/vmw_vsock/Makefile
+++ b/net/vmw_vsock/Makefile
@@ -8,6 +8,7 @@ obj-$(CONFIG_HYPERV_VSOCKETS) += hv_sock.o
obj-$(CONFIG_VSOCKETS_LOOPBACK) += vsock_loopback.o
vsock-y += af_vsock.o af_vsock_tap.o vsock_addr.o
+vsock-$(CONFIG_BPF_SYSCALL) += vsock_bpf.o
vsock_diag-y += diag.o
diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index 19aea7cba26e..5f2dda35c980 100644
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c
@@ -116,10 +116,13 @@ static void vsock_sk_destruct(struct sock *sk);
static int vsock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
/* Protocol family. */
-static struct proto vsock_proto = {
+struct proto vsock_proto = {
.name = "AF_VSOCK",
.owner = THIS_MODULE,
.obj_size = sizeof(struct vsock_sock),
+#ifdef CONFIG_BPF_SYSCALL
+ .psock_update_sk_prot = vsock_bpf_update_proto,
+#endif
};
/* The default peer timeout indicates how long we will wait for a peer response
@@ -865,7 +868,7 @@ s64 vsock_stream_has_data(struct vsock_sock *vsk)
}
EXPORT_SYMBOL_GPL(vsock_stream_has_data);
-static s64 vsock_connectible_has_data(struct vsock_sock *vsk)
+s64 vsock_connectible_has_data(struct vsock_sock *vsk)
{
struct sock *sk = sk_vsock(vsk);
@@ -874,6 +877,7 @@ static s64 vsock_connectible_has_data(struct vsock_sock *vsk)
else
return vsock_stream_has_data(vsk);
}
+EXPORT_SYMBOL_GPL(vsock_connectible_has_data);
s64 vsock_stream_has_space(struct vsock_sock *vsk)
{
@@ -1131,6 +1135,13 @@ static __poll_t vsock_poll(struct file *file, struct socket *sock,
return mask;
}
+static int vsock_read_skb(struct sock *sk, skb_read_actor_t read_actor)
+{
+ struct vsock_sock *vsk = vsock_sk(sk);
+
+ return vsk->transport->read_skb(vsk, read_actor);
+}
+
static int vsock_dgram_sendmsg(struct socket *sock, struct msghdr *msg,
size_t len)
{
@@ -1242,18 +1253,42 @@ static int vsock_dgram_connect(struct socket *sock,
memcpy(&vsk->remote_addr, remote_addr, sizeof(vsk->remote_addr));
sock->state = SS_CONNECTED;
+ /* sock map disallows redirection of non-TCP sockets with sk_state !=
+ * TCP_ESTABLISHED (see sock_map_redirect_allowed()), so we set
+ * TCP_ESTABLISHED here to allow redirection of connected vsock dgrams.
+ *
+ * This doesn't seem to be abnormal state for datagram sockets, as the
+ * same approach can be see in other datagram socket types as well
+ * (such as unix sockets).
+ */
+ sk->sk_state = TCP_ESTABLISHED;
+
out:
release_sock(sk);
return err;
}
-static int vsock_dgram_recvmsg(struct socket *sock, struct msghdr *msg,
- size_t len, int flags)
+int vsock_dgram_recvmsg(struct socket *sock, struct msghdr *msg,
+ size_t len, int flags)
{
- struct vsock_sock *vsk = vsock_sk(sock->sk);
+#ifdef CONFIG_BPF_SYSCALL
+ const struct proto *prot;
+#endif
+ struct vsock_sock *vsk;
+ struct sock *sk;
+
+ sk = sock->sk;
+ vsk = vsock_sk(sk);
+
+#ifdef CONFIG_BPF_SYSCALL
+ prot = READ_ONCE(sk->sk_prot);
+ if (prot != &vsock_proto)
+ return prot->recvmsg(sk, msg, len, flags, NULL);
+#endif
return vsk->transport->dgram_dequeue(vsk, msg, len, flags);
}
+EXPORT_SYMBOL_GPL(vsock_dgram_recvmsg);
static const struct proto_ops vsock_dgram_ops = {
.family = PF_VSOCK,
@@ -1272,6 +1307,7 @@ static const struct proto_ops vsock_dgram_ops = {
.recvmsg = vsock_dgram_recvmsg,
.mmap = sock_no_mmap,
.sendpage = sock_no_sendpage,
+ .read_skb = vsock_read_skb,
};
static int vsock_transport_cancel_pkt(struct vsock_sock *vsk)
@@ -2086,13 +2122,16 @@ out:
return err;
}
-static int
+int
vsock_connectible_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
int flags)
{
struct sock *sk;
struct vsock_sock *vsk;
const struct vsock_transport *transport;
+#ifdef CONFIG_BPF_SYSCALL
+ const struct proto *prot;
+#endif
int err;
sk = sock->sk;
@@ -2139,6 +2178,14 @@ vsock_connectible_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
goto out;
}
+#ifdef CONFIG_BPF_SYSCALL
+ prot = READ_ONCE(sk->sk_prot);
+ if (prot != &vsock_proto) {
+ release_sock(sk);
+ return prot->recvmsg(sk, msg, len, flags, NULL);
+ }
+#endif
+
if (sk->sk_type == SOCK_STREAM)
err = __vsock_stream_recvmsg(sk, msg, len, flags);
else
@@ -2148,6 +2195,7 @@ out:
release_sock(sk);
return err;
}
+EXPORT_SYMBOL_GPL(vsock_connectible_recvmsg);
static int vsock_set_rcvlowat(struct sock *sk, int val)
{
@@ -2188,6 +2236,7 @@ static const struct proto_ops vsock_stream_ops = {
.mmap = sock_no_mmap,
.sendpage = sock_no_sendpage,
.set_rcvlowat = vsock_set_rcvlowat,
+ .read_skb = vsock_read_skb,
};
static const struct proto_ops vsock_seqpacket_ops = {
@@ -2209,6 +2258,7 @@ static const struct proto_ops vsock_seqpacket_ops = {
.recvmsg = vsock_connectible_recvmsg,
.mmap = sock_no_mmap,
.sendpage = sock_no_sendpage,
+ .read_skb = vsock_read_skb,
};
static int vsock_create(struct net *net, struct socket *sock,
@@ -2348,6 +2398,8 @@ static int __init vsock_init(void)
goto err_unregister_proto;
}
+ vsock_bpf_build_proto();
+
return 0;
err_unregister_proto:
diff --git a/net/vmw_vsock/virtio_transport.c b/net/vmw_vsock/virtio_transport.c
index 28b5a8e8e094..e95df847176b 100644
--- a/net/vmw_vsock/virtio_transport.c
+++ b/net/vmw_vsock/virtio_transport.c
@@ -457,6 +457,8 @@ static struct virtio_transport virtio_transport = {
.notify_send_pre_enqueue = virtio_transport_notify_send_pre_enqueue,
.notify_send_post_enqueue = virtio_transport_notify_send_post_enqueue,
.notify_buffer_size = virtio_transport_notify_buffer_size,
+
+ .read_skb = virtio_transport_read_skb,
},
.send_pkt = virtio_transport_send_pkt,
diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c
index 7fc178c3ee07..f39639dd6eb5 100644
--- a/net/vmw_vsock/virtio_transport_common.c
+++ b/net/vmw_vsock/virtio_transport_common.c
@@ -1418,6 +1418,31 @@ int virtio_transport_purge_skbs(void *vsk, struct sk_buff_head *queue)
}
EXPORT_SYMBOL_GPL(virtio_transport_purge_skbs);
+int virtio_transport_read_skb(struct vsock_sock *vsk, skb_read_actor_t recv_actor)
+{
+ struct virtio_vsock_sock *vvs = vsk->trans;
+ struct sock *sk = sk_vsock(vsk);
+ struct sk_buff *skb;
+ int off = 0;
+ int copied;
+ int err;
+
+ spin_lock_bh(&vvs->rx_lock);
+ /* Use __skb_recv_datagram() for race-free handling of the receive. It
+ * works for types other than dgrams.
+ */
+ skb = __skb_recv_datagram(sk, &vvs->rx_queue, MSG_DONTWAIT, &off, &err);
+ spin_unlock_bh(&vvs->rx_lock);
+
+ if (!skb)
+ return err;
+
+ copied = recv_actor(sk, skb);
+ kfree_skb(skb);
+ return copied;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_read_skb);
+
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Asias He");
MODULE_DESCRIPTION("common code for virtio vsock");
diff --git a/net/vmw_vsock/vsock_bpf.c b/net/vmw_vsock/vsock_bpf.c
new file mode 100644
index 000000000000..a3c97546ab84
--- /dev/null
+++ b/net/vmw_vsock/vsock_bpf.c
@@ -0,0 +1,174 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2022 Bobby Eshleman <bobby.eshleman@bytedance.com>
+ *
+ * Based off of net/unix/unix_bpf.c
+ */
+
+#include <linux/bpf.h>
+#include <linux/module.h>
+#include <linux/skmsg.h>
+#include <linux/socket.h>
+#include <linux/wait.h>
+#include <net/af_vsock.h>
+#include <net/sock.h>
+
+#define vsock_sk_has_data(__sk, __psock) \
+ ({ !skb_queue_empty(&(__sk)->sk_receive_queue) || \
+ !skb_queue_empty(&(__psock)->ingress_skb) || \
+ !list_empty(&(__psock)->ingress_msg); \
+ })
+
+static struct proto *vsock_prot_saved __read_mostly;
+static DEFINE_SPINLOCK(vsock_prot_lock);
+static struct proto vsock_bpf_prot;
+
+static bool vsock_has_data(struct sock *sk, struct sk_psock *psock)
+{
+ struct vsock_sock *vsk = vsock_sk(sk);
+ s64 ret;
+
+ ret = vsock_connectible_has_data(vsk);
+ if (ret > 0)
+ return true;
+
+ return vsock_sk_has_data(sk, psock);
+}
+
+static bool vsock_msg_wait_data(struct sock *sk, struct sk_psock *psock, long timeo)
+{
+ bool ret;
+
+ DEFINE_WAIT_FUNC(wait, woken_wake_function);
+
+ if (sk->sk_shutdown & RCV_SHUTDOWN)
+ return true;
+
+ if (!timeo)
+ return false;
+
+ add_wait_queue(sk_sleep(sk), &wait);
+ sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
+ ret = vsock_has_data(sk, psock);
+ if (!ret) {
+ wait_woken(&wait, TASK_INTERRUPTIBLE, timeo);
+ ret = vsock_has_data(sk, psock);
+ }
+ sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
+ remove_wait_queue(sk_sleep(sk), &wait);
+ return ret;
+}
+
+static int __vsock_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int flags)
+{
+ struct socket *sock = sk->sk_socket;
+ int err;
+
+ if (sk->sk_type == SOCK_STREAM || sk->sk_type == SOCK_SEQPACKET)
+ err = vsock_connectible_recvmsg(sock, msg, len, flags);
+ else if (sk->sk_type == SOCK_DGRAM)
+ err = vsock_dgram_recvmsg(sock, msg, len, flags);
+ else
+ err = -EPROTOTYPE;
+
+ return err;
+}
+
+static int vsock_bpf_recvmsg(struct sock *sk, struct msghdr *msg,
+ size_t len, int flags, int *addr_len)
+{
+ struct sk_psock *psock;
+ int copied;
+
+ psock = sk_psock_get(sk);
+ if (unlikely(!psock))
+ return __vsock_recvmsg(sk, msg, len, flags);
+
+ lock_sock(sk);
+ if (vsock_has_data(sk, psock) && sk_psock_queue_empty(psock)) {
+ release_sock(sk);
+ sk_psock_put(sk, psock);
+ return __vsock_recvmsg(sk, msg, len, flags);
+ }
+
+ copied = sk_msg_recvmsg(sk, psock, msg, len, flags);
+ while (copied == 0) {
+ long timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
+
+ if (!vsock_msg_wait_data(sk, psock, timeo)) {
+ copied = -EAGAIN;
+ break;
+ }
+
+ if (sk_psock_queue_empty(psock)) {
+ release_sock(sk);
+ sk_psock_put(sk, psock);
+ return __vsock_recvmsg(sk, msg, len, flags);
+ }
+
+ copied = sk_msg_recvmsg(sk, psock, msg, len, flags);
+ }
+
+ release_sock(sk);
+ sk_psock_put(sk, psock);
+
+ return copied;
+}
+
+/* Copy of original proto with updated sock_map methods */
+static struct proto vsock_bpf_prot = {
+ .close = sock_map_close,
+ .recvmsg = vsock_bpf_recvmsg,
+ .sock_is_readable = sk_msg_is_readable,
+ .unhash = sock_map_unhash,
+};
+
+static void vsock_bpf_rebuild_protos(struct proto *prot, const struct proto *base)
+{
+ *prot = *base;
+ prot->close = sock_map_close;
+ prot->recvmsg = vsock_bpf_recvmsg;
+ prot->sock_is_readable = sk_msg_is_readable;
+}
+
+static void vsock_bpf_check_needs_rebuild(struct proto *ops)
+{
+ /* Paired with the smp_store_release() below. */
+ if (unlikely(ops != smp_load_acquire(&vsock_prot_saved))) {
+ spin_lock_bh(&vsock_prot_lock);
+ if (likely(ops != vsock_prot_saved)) {
+ vsock_bpf_rebuild_protos(&vsock_bpf_prot, ops);
+ /* Make sure proto function pointers are updated before publishing the
+ * pointer to the struct.
+ */
+ smp_store_release(&vsock_prot_saved, ops);
+ }
+ spin_unlock_bh(&vsock_prot_lock);
+ }
+}
+
+int vsock_bpf_update_proto(struct sock *sk, struct sk_psock *psock, bool restore)
+{
+ struct vsock_sock *vsk;
+
+ if (restore) {
+ sk->sk_write_space = psock->saved_write_space;
+ sock_replace_proto(sk, psock->sk_proto);
+ return 0;
+ }
+
+ vsk = vsock_sk(sk);
+ if (!vsk->transport)
+ return -ENODEV;
+
+ if (!vsk->transport->read_skb)
+ return -EOPNOTSUPP;
+
+ vsock_bpf_check_needs_rebuild(psock->sk_proto);
+ sock_replace_proto(sk, &vsock_bpf_prot);
+ return 0;
+}
+
+void __init vsock_bpf_build_proto(void)
+{
+ vsock_bpf_rebuild_protos(&vsock_bpf_prot, &vsock_proto);
+}
diff --git a/net/vmw_vsock/vsock_loopback.c b/net/vmw_vsock/vsock_loopback.c
index 671e03240fc5..40753b661c13 100644
--- a/net/vmw_vsock/vsock_loopback.c
+++ b/net/vmw_vsock/vsock_loopback.c
@@ -94,6 +94,8 @@ static struct virtio_transport loopback_transport = {
.notify_send_pre_enqueue = virtio_transport_notify_send_pre_enqueue,
.notify_send_post_enqueue = virtio_transport_notify_send_post_enqueue,
.notify_buffer_size = virtio_transport_notify_buffer_size,
+
+ .read_skb = virtio_transport_read_skb,
},
.send_pkt = vsock_loopback_send_pkt,