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authorAsias He <asias@redhat.com>2015-12-02 14:44:00 +0800
committerDavid S. Miller <davem@davemloft.net>2015-12-03 15:05:55 -0500
commit80a19e338d458abb5a700df3fd00795c51361f06 (patch)
tree21b556c267505997a81161f620ba18219166aec6 /net/vmw_vsock
parent357ab2234d57f6c74386f64ded42dff8e3c0500b (diff)
VSOCK: Introduce virtio-vsock-common.ko
This module contains the common code and header files for the following virtio-vsock and virtio-vhost kernel modules. Signed-off-by: Asias He <asias@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/vmw_vsock')
-rw-r--r--net/vmw_vsock/virtio_transport_common.c1272
1 files changed, 1272 insertions, 0 deletions
diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c
new file mode 100644
index 000000000000..28f790da6f15
--- /dev/null
+++ b/net/vmw_vsock/virtio_transport_common.c
@@ -0,0 +1,1272 @@
+/*
+ * common code for virtio vsock
+ *
+ * Copyright (C) 2013-2015 Red Hat, Inc.
+ * Author: Asias He <asias@redhat.com>
+ * Stefan Hajnoczi <stefanha@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.
+ */
+#include <linux/module.h>
+#include <linux/ctype.h>
+#include <linux/list.h>
+#include <linux/virtio.h>
+#include <linux/virtio_ids.h>
+#include <linux/virtio_config.h>
+#include <linux/virtio_vsock.h>
+#include <linux/random.h>
+#include <linux/cryptohash.h>
+
+#include <net/sock.h>
+#include <net/af_vsock.h>
+
+#define COOKIEBITS 24
+#define COOKIEMASK (((u32)1 << COOKIEBITS) - 1)
+#define VSOCK_TIMEOUT_INIT 4
+
+#define SHA_MESSAGE_WORDS 16
+#define SHA_VSOCK_WORDS 5
+
+static u32 vsockcookie_secret[2][SHA_MESSAGE_WORDS - SHA_VSOCK_WORDS +
+ SHA_DIGEST_WORDS];
+
+static DEFINE_PER_CPU(__u32[SHA_MESSAGE_WORDS + SHA_DIGEST_WORDS +
+ SHA_WORKSPACE_WORDS], vsock_cookie_scratch);
+
+static u32 cookie_hash(u32 saddr, u32 daddr, u16 sport, u16 dport,
+ u32 count, int c)
+{
+ __u32 *tmp = this_cpu_ptr(vsock_cookie_scratch);
+
+ memcpy(tmp + SHA_VSOCK_WORDS, vsockcookie_secret[c],
+ sizeof(vsockcookie_secret[c]));
+ tmp[0] = saddr;
+ tmp[1] = daddr;
+ tmp[2] = sport;
+ tmp[3] = dport;
+ tmp[4] = count;
+ sha_transform(tmp + SHA_MESSAGE_WORDS, (__u8 *)tmp,
+ tmp + SHA_MESSAGE_WORDS + SHA_DIGEST_WORDS);
+
+ return tmp[17];
+}
+
+static u32
+virtio_vsock_secure_cookie(u32 saddr, u32 daddr, u32 sport, u32 dport,
+ u32 count)
+{
+ u32 h1, h2;
+
+ h1 = cookie_hash(saddr, daddr, sport, dport, 0, 0);
+ h2 = cookie_hash(saddr, daddr, sport, dport, count, 1);
+
+ return h1 + (count << COOKIEBITS) + (h2 & COOKIEMASK);
+}
+
+static u32
+virtio_vsock_check_cookie(u32 saddr, u32 daddr, u32 sport, u32 dport,
+ u32 count, u32 cookie, u32 maxdiff)
+{
+ u32 diff;
+ u32 ret;
+
+ cookie -= cookie_hash(saddr, daddr, sport, dport, 0, 0);
+
+ diff = (count - (cookie >> COOKIEBITS)) & ((u32)-1 >> COOKIEBITS);
+ pr_debug("%s: diff=%x\n", __func__, diff);
+ if (diff >= maxdiff)
+ return (u32)-1;
+
+ ret = (cookie -
+ cookie_hash(saddr, daddr, sport, dport, count - diff, 1))
+ & COOKIEMASK;
+ pr_debug("%s: ret=%x\n", __func__, diff);
+
+ return ret;
+}
+
+void virtio_vsock_dumppkt(const char *func, const struct virtio_vsock_pkt *pkt)
+{
+ pr_debug("%s: pkt=%p, op=%d, len=%d, %d:%d---%d:%d, len=%d\n",
+ func, pkt,
+ le16_to_cpu(pkt->hdr.op),
+ le32_to_cpu(pkt->hdr.len),
+ le32_to_cpu(pkt->hdr.src_cid),
+ le32_to_cpu(pkt->hdr.src_port),
+ le32_to_cpu(pkt->hdr.dst_cid),
+ le32_to_cpu(pkt->hdr.dst_port),
+ pkt->len);
+}
+EXPORT_SYMBOL_GPL(virtio_vsock_dumppkt);
+
+struct virtio_vsock_pkt *
+virtio_transport_alloc_pkt(struct vsock_sock *vsk,
+ struct virtio_vsock_pkt_info *info,
+ size_t len,
+ u32 src_cid,
+ u32 src_port,
+ u32 dst_cid,
+ u32 dst_port)
+{
+ struct virtio_transport *trans = vsk->trans;
+ struct virtio_vsock_pkt *pkt;
+ int err;
+
+ BUG_ON(!trans);
+
+ pkt = kzalloc(sizeof(*pkt), GFP_KERNEL);
+ if (!pkt)
+ return NULL;
+
+ pkt->hdr.type = cpu_to_le16(info->type);
+ pkt->hdr.op = cpu_to_le16(info->op);
+ pkt->hdr.src_cid = cpu_to_le32(src_cid);
+ pkt->hdr.src_port = cpu_to_le32(src_port);
+ pkt->hdr.dst_cid = cpu_to_le32(dst_cid);
+ pkt->hdr.dst_port = cpu_to_le32(dst_port);
+ pkt->hdr.flags = cpu_to_le32(info->flags);
+ pkt->len = len;
+ pkt->trans = trans;
+ if (info->type == VIRTIO_VSOCK_TYPE_DGRAM)
+ pkt->hdr.len = cpu_to_le32(len + (info->dgram_len << 16));
+ else if (info->type == VIRTIO_VSOCK_TYPE_STREAM)
+ pkt->hdr.len = cpu_to_le32(len);
+
+ if (info->msg && len > 0) {
+ pkt->buf = kmalloc(len, GFP_KERNEL);
+ if (!pkt->buf)
+ goto out_pkt;
+ err = memcpy_from_msg(pkt->buf, info->msg, len);
+ if (err)
+ goto out;
+ }
+
+ return pkt;
+
+out:
+ kfree(pkt->buf);
+out_pkt:
+ kfree(pkt);
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_alloc_pkt);
+
+struct sock *
+virtio_transport_get_pending(struct sock *listener,
+ struct virtio_vsock_pkt *pkt)
+{
+ struct vsock_sock *vlistener;
+ struct vsock_sock *vpending;
+ struct sockaddr_vm src;
+ struct sockaddr_vm dst;
+ struct sock *pending;
+
+ vsock_addr_init(&src, le32_to_cpu(pkt->hdr.src_cid), le32_to_cpu(pkt->hdr.src_port));
+ vsock_addr_init(&dst, le32_to_cpu(pkt->hdr.dst_cid), le32_to_cpu(pkt->hdr.dst_port));
+
+ vlistener = vsock_sk(listener);
+ list_for_each_entry(vpending, &vlistener->pending_links,
+ pending_links) {
+ if (vsock_addr_equals_addr(&src, &vpending->remote_addr) &&
+ vsock_addr_equals_addr(&dst, &vpending->local_addr)) {
+ pending = sk_vsock(vpending);
+ sock_hold(pending);
+ return pending;
+ }
+ }
+
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_get_pending);
+
+static void virtio_transport_inc_rx_pkt(struct virtio_vsock_pkt *pkt)
+{
+ pkt->trans->rx_bytes += pkt->len;
+}
+
+static void virtio_transport_dec_rx_pkt(struct virtio_vsock_pkt *pkt)
+{
+ pkt->trans->rx_bytes -= pkt->len;
+ pkt->trans->fwd_cnt += pkt->len;
+}
+
+void virtio_transport_inc_tx_pkt(struct virtio_vsock_pkt *pkt)
+{
+ mutex_lock(&pkt->trans->tx_lock);
+ pkt->hdr.fwd_cnt = cpu_to_le32(pkt->trans->fwd_cnt);
+ pkt->hdr.buf_alloc = cpu_to_le32(pkt->trans->buf_alloc);
+ mutex_unlock(&pkt->trans->tx_lock);
+}
+EXPORT_SYMBOL_GPL(virtio_transport_inc_tx_pkt);
+
+void virtio_transport_dec_tx_pkt(struct virtio_vsock_pkt *pkt)
+{
+}
+EXPORT_SYMBOL_GPL(virtio_transport_dec_tx_pkt);
+
+u32 virtio_transport_get_credit(struct virtio_transport *trans, u32 credit)
+{
+ u32 ret;
+
+ mutex_lock(&trans->tx_lock);
+ ret = trans->peer_buf_alloc - (trans->tx_cnt - trans->peer_fwd_cnt);
+ if (ret > credit)
+ ret = credit;
+ trans->tx_cnt += ret;
+ mutex_unlock(&trans->tx_lock);
+
+ pr_debug("%s: ret=%d, buf_alloc=%d, peer_buf_alloc=%d,"
+ "tx_cnt=%d, fwd_cnt=%d, peer_fwd_cnt=%d\n", __func__,
+ ret, trans->buf_alloc, trans->peer_buf_alloc,
+ trans->tx_cnt, trans->fwd_cnt, trans->peer_fwd_cnt);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_get_credit);
+
+void virtio_transport_put_credit(struct virtio_transport *trans, u32 credit)
+{
+ mutex_lock(&trans->tx_lock);
+ trans->tx_cnt -= credit;
+ mutex_unlock(&trans->tx_lock);
+}
+EXPORT_SYMBOL_GPL(virtio_transport_put_credit);
+
+static int virtio_transport_send_credit_update(struct vsock_sock *vsk, int type, struct virtio_vsock_hdr *hdr)
+{
+ struct virtio_transport *trans = vsk->trans;
+ struct virtio_vsock_pkt_info info = {
+ .op = VIRTIO_VSOCK_OP_CREDIT_UPDATE,
+ .type = type,
+ };
+
+ if (hdr && type == VIRTIO_VSOCK_TYPE_DGRAM) {
+ info.remote_cid = le32_to_cpu(hdr->src_cid);
+ info.remote_port = le32_to_cpu(hdr->src_port);
+ }
+
+ pr_debug("%s: sk=%p send_credit_update\n", __func__, vsk);
+ return trans->ops->send_pkt(vsk, &info);
+}
+
+static int virtio_transport_send_credit_request(struct vsock_sock *vsk, int type)
+{
+ struct virtio_transport *trans = vsk->trans;
+ struct virtio_vsock_pkt_info info = {
+ .op = VIRTIO_VSOCK_OP_CREDIT_REQUEST,
+ .type = type,
+ };
+
+ pr_debug("%s: sk=%p send_credit_request\n", __func__, vsk);
+ return trans->ops->send_pkt(vsk, &info);
+}
+
+static ssize_t
+virtio_transport_stream_do_dequeue(struct vsock_sock *vsk,
+ struct msghdr *msg,
+ size_t len)
+{
+ struct virtio_transport *trans = vsk->trans;
+ struct virtio_vsock_pkt *pkt;
+ size_t bytes, total = 0;
+ int err = -EFAULT;
+
+ mutex_lock(&trans->rx_lock);
+ while (total < len && trans->rx_bytes > 0 &&
+ !list_empty(&trans->rx_queue)) {
+ pkt = list_first_entry(&trans->rx_queue,
+ struct virtio_vsock_pkt, list);
+
+ bytes = len - total;
+ if (bytes > pkt->len - pkt->off)
+ bytes = pkt->len - pkt->off;
+
+ err = memcpy_to_msg(msg, pkt->buf + pkt->off, bytes);
+ if (err)
+ goto out;
+ total += bytes;
+ pkt->off += bytes;
+ if (pkt->off == pkt->len) {
+ virtio_transport_dec_rx_pkt(pkt);
+ list_del(&pkt->list);
+ virtio_transport_free_pkt(pkt);
+ }
+ }
+ mutex_unlock(&trans->rx_lock);
+
+ /* Send a credit pkt to peer */
+ virtio_transport_send_credit_update(vsk, VIRTIO_VSOCK_TYPE_STREAM,
+ NULL);
+
+ return total;
+
+out:
+ mutex_unlock(&trans->rx_lock);
+ if (total)
+ err = total;
+ return err;
+}
+
+ssize_t
+virtio_transport_stream_dequeue(struct vsock_sock *vsk,
+ struct msghdr *msg,
+ size_t len, int flags)
+{
+ if (flags & MSG_PEEK)
+ return -EOPNOTSUPP;
+
+ return virtio_transport_stream_do_dequeue(vsk, msg, len);
+}
+EXPORT_SYMBOL_GPL(virtio_transport_stream_dequeue);
+
+struct dgram_skb {
+ struct list_head list;
+ struct sk_buff *skb;
+ u16 id;
+};
+
+static struct dgram_skb *dgram_id_to_skb(struct virtio_transport *trans,
+ u16 id)
+{
+ struct dgram_skb *dgram_skb;
+
+ list_for_each_entry(dgram_skb, &trans->incomplete_dgrams, list) {
+ if (dgram_skb->id == id)
+ return dgram_skb;
+ }
+
+ return NULL;
+}
+
+static void
+virtio_transport_recv_dgram(struct sock *sk,
+ struct virtio_vsock_pkt *pkt)
+{
+ struct sk_buff *skb = NULL;
+ struct vsock_sock *vsk;
+ struct virtio_transport *trans;
+ size_t size;
+ u16 dgram_id, pkt_off, dgram_len, pkt_len;
+ u32 flags, len;
+ struct dgram_skb *dgram_skb;
+
+ vsk = vsock_sk(sk);
+ trans = vsk->trans;
+
+ /* len: dgram_len | pkt_len */
+ len = le32_to_cpu(pkt->hdr.len);
+ dgram_len = len >> 16;
+ pkt_len = len & 0xFFFF;
+
+ /* flags: dgram_id | pkt_off */
+ flags = le32_to_cpu(pkt->hdr.flags);
+ dgram_id = flags >> 16;
+ pkt_off = flags & 0xFFFF;
+
+ pr_debug("%s: dgram_len=%d, pkt_len=%d, id=%d, off=%d\n", __func__,
+ dgram_len, pkt_len, dgram_id, pkt_off);
+
+ dgram_skb = dgram_id_to_skb(trans, dgram_id);
+ if (dgram_skb) {
+ /* This pkt is for a existing dgram */
+ skb = dgram_skb->skb;
+ pr_debug("%s:found skb\n", __func__);
+ }
+
+ /* Packet payload must be within datagram bounds */
+ if (pkt_len > VIRTIO_VSOCK_DEFAULT_RX_BUF_SIZE)
+ goto drop;
+ if (pkt_len > dgram_len)
+ goto drop;
+ if (pkt_off > dgram_len)
+ goto drop;
+ if (dgram_len - pkt_off < pkt_len)
+ goto drop;
+
+ if (!skb) {
+ /* This pkt is for a new dgram */
+ pr_debug("%s:create skb\n", __func__);
+
+ size = sizeof(pkt->hdr) + dgram_len;
+ /* Attach the packet to the socket's receive queue as an sk_buff. */
+ dgram_skb = kzalloc(sizeof(struct dgram_skb), GFP_ATOMIC);
+ if (!dgram_skb)
+ goto drop;
+
+ skb = alloc_skb(size, GFP_ATOMIC);
+ if (!skb) {
+ kfree(dgram_skb);
+ dgram_skb = NULL;
+ goto drop;
+ }
+ dgram_skb->id = dgram_id;
+ dgram_skb->skb = skb;
+ list_add_tail(&dgram_skb->list, &trans->incomplete_dgrams);
+
+ /* sk_receive_skb() will do a sock_put(), so hold here. */
+ sock_hold(sk);
+ skb_put(skb, size);
+ memcpy(skb->data, &pkt->hdr, sizeof(pkt->hdr));
+ }
+
+ memcpy(skb->data + sizeof(pkt->hdr) + pkt_off, pkt->buf, pkt_len);
+
+ pr_debug("%s:C, off=%d, pkt_len=%d, dgram_len=%d\n", __func__,
+ pkt_off, pkt_len, dgram_len);
+
+ /* We are done with this dgram */
+ if (pkt_off + pkt_len == dgram_len) {
+ pr_debug("%s:dgram_id=%d is done\n", __func__, dgram_id);
+ list_del(&dgram_skb->list);
+ kfree(dgram_skb);
+ sk_receive_skb(sk, skb, 0);
+ }
+ virtio_transport_free_pkt(pkt);
+ return;
+
+drop:
+ if (dgram_skb) {
+ list_del(&dgram_skb->list);
+ kfree(dgram_skb);
+ kfree_skb(skb);
+ sock_put(sk);
+ }
+ virtio_transport_free_pkt(pkt);
+}
+
+int
+virtio_transport_dgram_dequeue(struct vsock_sock *vsk,
+ struct msghdr *msg,
+ size_t len, int flags)
+{
+ struct virtio_vsock_hdr *hdr;
+ struct sk_buff *skb;
+ int noblock;
+ int err;
+ int dgram_len;
+
+ noblock = flags & MSG_DONTWAIT;
+
+ 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, noblock, &err);
+ if (err)
+ return err;
+ if (!skb)
+ return -EAGAIN;
+
+ hdr = (struct virtio_vsock_hdr *)skb->data;
+ if (!hdr)
+ goto out;
+
+ dgram_len = le32_to_cpu(hdr->len) >> 16;
+ /* Place the datagram payload in the user's iovec. */
+ err = skb_copy_datagram_msg(skb, sizeof(*hdr), msg, dgram_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, le32_to_cpu(hdr->src_cid), le32_to_cpu(hdr->src_port));
+ msg->msg_namelen = sizeof(*vm_addr);
+ }
+ err = dgram_len;
+
+ /* Send a credit pkt to peer */
+ virtio_transport_send_credit_update(vsk, VIRTIO_VSOCK_TYPE_DGRAM, hdr);
+
+ pr_debug("%s:done, recved =%d\n", __func__, dgram_len);
+out:
+ skb_free_datagram(&vsk->sk, skb);
+ return err;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_dgram_dequeue);
+
+s64 virtio_transport_stream_has_data(struct vsock_sock *vsk)
+{
+ struct virtio_transport *trans = vsk->trans;
+ s64 bytes;
+
+ mutex_lock(&trans->rx_lock);
+ bytes = trans->rx_bytes;
+ mutex_unlock(&trans->rx_lock);
+
+ return bytes;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_stream_has_data);
+
+static s64 virtio_transport_has_space(struct vsock_sock *vsk)
+{
+ struct virtio_transport *trans = vsk->trans;
+ s64 bytes;
+
+ bytes = trans->peer_buf_alloc - (trans->tx_cnt - trans->peer_fwd_cnt);
+ if (bytes < 0)
+ bytes = 0;
+
+ return bytes;
+}
+
+s64 virtio_transport_stream_has_space(struct vsock_sock *vsk)
+{
+ struct virtio_transport *trans = vsk->trans;
+ s64 bytes;
+
+ mutex_lock(&trans->tx_lock);
+ bytes = virtio_transport_has_space(vsk);
+ mutex_unlock(&trans->tx_lock);
+
+ pr_debug("%s: bytes=%lld\n", __func__, bytes);
+
+ return bytes;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_stream_has_space);
+
+int virtio_transport_do_socket_init(struct vsock_sock *vsk,
+ struct vsock_sock *psk)
+{
+ struct virtio_transport *trans;
+
+ trans = kzalloc(sizeof(*trans), GFP_KERNEL);
+ if (!trans)
+ return -ENOMEM;
+
+ vsk->trans = trans;
+ trans->vsk = vsk;
+ if (psk) {
+ struct virtio_transport *ptrans = psk->trans;
+ trans->buf_size = ptrans->buf_size;
+ trans->buf_size_min = ptrans->buf_size_min;
+ trans->buf_size_max = ptrans->buf_size_max;
+ trans->peer_buf_alloc = ptrans->peer_buf_alloc;
+ } else {
+ trans->buf_size = VIRTIO_VSOCK_DEFAULT_BUF_SIZE;
+ trans->buf_size_min = VIRTIO_VSOCK_DEFAULT_MIN_BUF_SIZE;
+ trans->buf_size_max = VIRTIO_VSOCK_DEFAULT_MAX_BUF_SIZE;
+ }
+
+ trans->buf_alloc = trans->buf_size;
+
+ pr_debug("%s: trans->buf_alloc=%d\n", __func__, trans->buf_alloc);
+
+ mutex_init(&trans->rx_lock);
+ mutex_init(&trans->tx_lock);
+ INIT_LIST_HEAD(&trans->rx_queue);
+ INIT_LIST_HEAD(&trans->incomplete_dgrams);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_do_socket_init);
+
+u64 virtio_transport_get_buffer_size(struct vsock_sock *vsk)
+{
+ struct virtio_transport *trans = vsk->trans;
+
+ return trans->buf_size;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_get_buffer_size);
+
+u64 virtio_transport_get_min_buffer_size(struct vsock_sock *vsk)
+{
+ struct virtio_transport *trans = vsk->trans;
+
+ return trans->buf_size_min;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_get_min_buffer_size);
+
+u64 virtio_transport_get_max_buffer_size(struct vsock_sock *vsk)
+{
+ struct virtio_transport *trans = vsk->trans;
+
+ return trans->buf_size_max;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_get_max_buffer_size);
+
+void virtio_transport_set_buffer_size(struct vsock_sock *vsk, u64 val)
+{
+ struct virtio_transport *trans = vsk->trans;
+
+ if (val > VIRTIO_VSOCK_MAX_BUF_SIZE)
+ val = VIRTIO_VSOCK_MAX_BUF_SIZE;
+ if (val < trans->buf_size_min)
+ trans->buf_size_min = val;
+ if (val > trans->buf_size_max)
+ trans->buf_size_max = val;
+ trans->buf_size = val;
+ trans->buf_alloc = val;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_set_buffer_size);
+
+void virtio_transport_set_min_buffer_size(struct vsock_sock *vsk, u64 val)
+{
+ struct virtio_transport *trans = vsk->trans;
+
+ if (val > VIRTIO_VSOCK_MAX_BUF_SIZE)
+ val = VIRTIO_VSOCK_MAX_BUF_SIZE;
+ if (val > trans->buf_size)
+ trans->buf_size = val;
+ trans->buf_size_min = val;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_set_min_buffer_size);
+
+void virtio_transport_set_max_buffer_size(struct vsock_sock *vsk, u64 val)
+{
+ struct virtio_transport *trans = vsk->trans;
+
+ if (val > VIRTIO_VSOCK_MAX_BUF_SIZE)
+ val = VIRTIO_VSOCK_MAX_BUF_SIZE;
+ if (val < trans->buf_size)
+ trans->buf_size = val;
+ trans->buf_size_max = val;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_set_max_buffer_size);
+
+int
+virtio_transport_notify_poll_in(struct vsock_sock *vsk,
+ size_t target,
+ bool *data_ready_now)
+{
+ if (vsock_stream_has_data(vsk))
+ *data_ready_now = true;
+ else
+ *data_ready_now = false;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_notify_poll_in);
+
+int
+virtio_transport_notify_poll_out(struct vsock_sock *vsk,
+ size_t target,
+ bool *space_avail_now)
+{
+ s64 free_space;
+
+ free_space = vsock_stream_has_space(vsk);
+ if (free_space > 0)
+ *space_avail_now = true;
+ else if (free_space == 0)
+ *space_avail_now = false;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_notify_poll_out);
+
+int virtio_transport_notify_recv_init(struct vsock_sock *vsk,
+ size_t target, struct vsock_transport_recv_notify_data *data)
+{
+ return 0;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_notify_recv_init);
+
+int virtio_transport_notify_recv_pre_block(struct vsock_sock *vsk,
+ size_t target, struct vsock_transport_recv_notify_data *data)
+{
+ return 0;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_notify_recv_pre_block);
+
+int virtio_transport_notify_recv_pre_dequeue(struct vsock_sock *vsk,
+ size_t target, struct vsock_transport_recv_notify_data *data)
+{
+ return 0;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_notify_recv_pre_dequeue);
+
+int virtio_transport_notify_recv_post_dequeue(struct vsock_sock *vsk,
+ size_t target, ssize_t copied, bool data_read,
+ struct vsock_transport_recv_notify_data *data)
+{
+ return 0;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_notify_recv_post_dequeue);
+
+int virtio_transport_notify_send_init(struct vsock_sock *vsk,
+ struct vsock_transport_send_notify_data *data)
+{
+ return 0;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_notify_send_init);
+
+int virtio_transport_notify_send_pre_block(struct vsock_sock *vsk,
+ struct vsock_transport_send_notify_data *data)
+{
+ return 0;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_notify_send_pre_block);
+
+int virtio_transport_notify_send_pre_enqueue(struct vsock_sock *vsk,
+ struct vsock_transport_send_notify_data *data)
+{
+ return 0;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_notify_send_pre_enqueue);
+
+int virtio_transport_notify_send_post_enqueue(struct vsock_sock *vsk,
+ ssize_t written, struct vsock_transport_send_notify_data *data)
+{
+ return 0;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_notify_send_post_enqueue);
+
+u64 virtio_transport_stream_rcvhiwat(struct vsock_sock *vsk)
+{
+ struct virtio_transport *trans = vsk->trans;
+
+ return trans->buf_size;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_stream_rcvhiwat);
+
+bool virtio_transport_stream_is_active(struct vsock_sock *vsk)
+{
+ return true;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_stream_is_active);
+
+bool virtio_transport_stream_allow(u32 cid, u32 port)
+{
+ return true;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_stream_allow);
+
+int virtio_transport_dgram_bind(struct vsock_sock *vsk,
+ struct sockaddr_vm *addr)
+{
+ return vsock_bind_dgram_generic(vsk, addr);
+}
+EXPORT_SYMBOL_GPL(virtio_transport_dgram_bind);
+
+bool virtio_transport_dgram_allow(u32 cid, u32 port)
+{
+ return true;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_dgram_allow);
+
+int virtio_transport_connect(struct vsock_sock *vsk)
+{
+ struct virtio_transport *trans = vsk->trans;
+ struct virtio_vsock_pkt_info info = {
+ .op = VIRTIO_VSOCK_OP_REQUEST,
+ .type = VIRTIO_VSOCK_TYPE_STREAM,
+ };
+
+ pr_debug("%s: vsk=%p send_request\n", __func__, vsk);
+ return trans->ops->send_pkt(vsk, &info);
+}
+EXPORT_SYMBOL_GPL(virtio_transport_connect);
+
+int virtio_transport_shutdown(struct vsock_sock *vsk, int mode)
+{
+ struct virtio_transport *trans = vsk->trans;
+ struct virtio_vsock_pkt_info info = {
+ .op = VIRTIO_VSOCK_OP_SHUTDOWN,
+ .type = VIRTIO_VSOCK_TYPE_STREAM,
+ .flags = (mode & RCV_SHUTDOWN ?
+ VIRTIO_VSOCK_SHUTDOWN_RCV : 0) |
+ (mode & SEND_SHUTDOWN ?
+ VIRTIO_VSOCK_SHUTDOWN_SEND : 0),
+ };
+
+ pr_debug("%s: vsk=%p: send_shutdown\n", __func__, vsk);
+ return trans->ops->send_pkt(vsk, &info);
+}
+EXPORT_SYMBOL_GPL(virtio_transport_shutdown);
+
+void virtio_transport_release(struct vsock_sock *vsk)
+{
+ struct virtio_transport *trans = vsk->trans;
+ struct sock *sk = &vsk->sk;
+ struct dgram_skb *dgram_skb;
+ struct dgram_skb *dgram_skb_tmp;
+
+ pr_debug("%s: vsk=%p\n", __func__, vsk);
+
+ /* Tell other side to terminate connection */
+ if (sk->sk_type == SOCK_STREAM && sk->sk_state == SS_CONNECTED) {
+ virtio_transport_shutdown(vsk, SHUTDOWN_MASK);
+ }
+
+ /* Free incomplete dgrams */
+ lock_sock(sk);
+ list_for_each_entry_safe(dgram_skb, dgram_skb_tmp,
+ &trans->incomplete_dgrams, list) {
+ list_del(&dgram_skb->list);
+ kfree_skb(dgram_skb->skb);
+ kfree(dgram_skb);
+ sock_put(sk); /* held in virtio_transport_recv_dgram() */
+ }
+ release_sock(sk);
+}
+EXPORT_SYMBOL_GPL(virtio_transport_release);
+
+int
+virtio_transport_dgram_enqueue(struct vsock_sock *vsk,
+ struct sockaddr_vm *remote_addr,
+ struct msghdr *msg,
+ size_t dgram_len)
+{
+ struct virtio_transport *trans = vsk->trans;
+ struct virtio_vsock_pkt_info info = {
+ .op = VIRTIO_VSOCK_OP_RW,
+ .type = VIRTIO_VSOCK_TYPE_DGRAM,
+ .msg = msg,
+ };
+ size_t total_written = 0, pkt_off = 0, written;
+ u16 dgram_id;
+
+ /* The max size of a single dgram we support is 64KB */
+ if (dgram_len > VIRTIO_VSOCK_MAX_DGRAM_SIZE)
+ return -EMSGSIZE;
+
+ info.dgram_len = dgram_len;
+ vsk->remote_addr = *remote_addr;
+
+ dgram_id = trans->dgram_id++;
+
+ /* TODO: To optimize, if we have enough credit to send the pkt already,
+ * do not ask the peer to send credit to use */
+ virtio_transport_send_credit_request(vsk, VIRTIO_VSOCK_TYPE_DGRAM);
+
+ while (total_written < dgram_len) {
+ info.pkt_len = dgram_len - total_written;
+ info.flags = dgram_id << 16 | pkt_off;
+ written = trans->ops->send_pkt(vsk, &info);
+ if (written < 0)
+ return -ENOMEM;
+ if (written == 0) {
+ /* TODO: if written = 0, we need a sleep & wakeup
+ * instead of sleep */
+ pr_debug("%s: SHOULD WAIT written==0", __func__);
+ msleep(10);
+ }
+ total_written += written;
+ pkt_off += written;
+ pr_debug("%s:id=%d, dgram_len=%zu, off=%zu, total_written=%zu, written=%zu\n",
+ __func__, dgram_id, dgram_len, pkt_off, total_written, written);
+ }
+
+ return dgram_len;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_dgram_enqueue);
+
+ssize_t
+virtio_transport_stream_enqueue(struct vsock_sock *vsk,
+ struct msghdr *msg,
+ size_t len)
+{
+ struct virtio_transport *trans = vsk->trans;
+ struct virtio_vsock_pkt_info info = {
+ .op = VIRTIO_VSOCK_OP_RW,
+ .type = VIRTIO_VSOCK_TYPE_STREAM,
+ .msg = msg,
+ .pkt_len = len,
+ };
+
+ return trans->ops->send_pkt(vsk, &info);
+}
+EXPORT_SYMBOL_GPL(virtio_transport_stream_enqueue);
+
+void virtio_transport_destruct(struct vsock_sock *vsk)
+{
+ struct virtio_transport *trans = vsk->trans;
+
+ pr_debug("%s: vsk=%p\n", __func__, vsk);
+ kfree(trans);
+}
+EXPORT_SYMBOL_GPL(virtio_transport_destruct);
+
+static int virtio_transport_send_ack(struct vsock_sock *vsk, u32 cookie)
+{
+ struct virtio_transport *trans = vsk->trans;
+ struct virtio_vsock_pkt_info info = {
+ .op = VIRTIO_VSOCK_OP_ACK,
+ .type = VIRTIO_VSOCK_TYPE_STREAM,
+ .flags = cpu_to_le32(cookie),
+ };
+
+ pr_debug("%s: sk=%p send_offer\n", __func__, vsk);
+ return trans->ops->send_pkt(vsk, &info);
+}
+
+static int virtio_transport_send_reset(struct vsock_sock *vsk,
+ struct virtio_vsock_pkt *pkt)
+{
+ struct virtio_transport *trans = vsk->trans;
+ struct virtio_vsock_pkt_info info = {
+ .op = VIRTIO_VSOCK_OP_RST,
+ .type = VIRTIO_VSOCK_TYPE_STREAM,
+ };
+
+ pr_debug("%s\n", __func__);
+
+ /* Send RST only if the original pkt is not a RST pkt */
+ if (le16_to_cpu(pkt->hdr.op) == VIRTIO_VSOCK_OP_RST)
+ return 0;
+
+ return trans->ops->send_pkt(vsk, &info);
+}
+
+static int
+virtio_transport_recv_connecting(struct sock *sk,
+ struct virtio_vsock_pkt *pkt)
+{
+ struct vsock_sock *vsk = vsock_sk(sk);
+ int err;
+ int skerr;
+ u32 cookie;
+
+ pr_debug("%s: vsk=%p\n", __func__, vsk);
+ switch (le16_to_cpu(pkt->hdr.op)) {
+ case VIRTIO_VSOCK_OP_RESPONSE:
+ cookie = le32_to_cpu(pkt->hdr.flags);
+ pr_debug("%s: got RESPONSE and send ACK, cookie=%x\n", __func__, cookie);
+ err = virtio_transport_send_ack(vsk, cookie);
+ if (err < 0) {
+ skerr = -err;
+ goto destroy;
+ }
+ sk->sk_state = SS_CONNECTED;
+ sk->sk_socket->state = SS_CONNECTED;
+ vsock_insert_connected(vsk);
+ sk->sk_state_change(sk);
+ break;
+ case VIRTIO_VSOCK_OP_INVALID:
+ pr_debug("%s: got invalid\n", __func__);
+ break;
+ case VIRTIO_VSOCK_OP_RST:
+ pr_debug("%s: got rst\n", __func__);
+ skerr = ECONNRESET;
+ err = 0;
+ goto destroy;
+ default:
+ pr_debug("%s: got def\n", __func__);
+ skerr = EPROTO;
+ err = -EINVAL;
+ goto destroy;
+ }
+ return 0;
+
+destroy:
+ virtio_transport_send_reset(vsk, pkt);
+ sk->sk_state = SS_UNCONNECTED;
+ sk->sk_err = skerr;
+ sk->sk_error_report(sk);
+ return err;
+}
+
+static int
+virtio_transport_recv_connected(struct sock *sk,
+ struct virtio_vsock_pkt *pkt)
+{
+ struct vsock_sock *vsk = vsock_sk(sk);
+ struct virtio_transport *trans = vsk->trans;
+ int err = 0;
+
+ switch (le16_to_cpu(pkt->hdr.op)) {
+ case VIRTIO_VSOCK_OP_RW:
+ pkt->len = le32_to_cpu(pkt->hdr.len);
+ pkt->off = 0;
+ pkt->trans = trans;
+
+ mutex_lock(&trans->rx_lock);
+ virtio_transport_inc_rx_pkt(pkt);
+ list_add_tail(&pkt->list, &trans->rx_queue);
+ mutex_unlock(&trans->rx_lock);
+
+ sk->sk_data_ready(sk);
+ return err;
+ case VIRTIO_VSOCK_OP_CREDIT_UPDATE:
+ sk->sk_write_space(sk);
+ break;
+ case VIRTIO_VSOCK_OP_SHUTDOWN:
+ pr_debug("%s: got shutdown\n", __func__);
+ if (le32_to_cpu(pkt->hdr.flags) & VIRTIO_VSOCK_SHUTDOWN_RCV)
+ vsk->peer_shutdown |= RCV_SHUTDOWN;
+ if (le32_to_cpu(pkt->hdr.flags) & VIRTIO_VSOCK_SHUTDOWN_SEND)
+ vsk->peer_shutdown |= SEND_SHUTDOWN;
+ if (le32_to_cpu(pkt->hdr.flags))
+ sk->sk_state_change(sk);
+ break;
+ case VIRTIO_VSOCK_OP_RST:
+ pr_debug("%s: got rst\n", __func__);
+ sock_set_flag(sk, SOCK_DONE);
+ vsk->peer_shutdown = SHUTDOWN_MASK;
+ if (vsock_stream_has_data(vsk) <= 0)
+ sk->sk_state = SS_DISCONNECTING;
+ sk->sk_state_change(sk);
+ break;
+ default:
+ err = -EINVAL;
+ break;
+ }
+
+ virtio_transport_free_pkt(pkt);
+ return err;
+}
+
+static int
+virtio_transport_send_response(struct vsock_sock *vsk,
+ struct virtio_vsock_pkt *pkt)
+{
+ struct virtio_transport *trans = vsk->trans;
+ struct virtio_vsock_pkt_info info = {
+ .op = VIRTIO_VSOCK_OP_RESPONSE,
+ .type = VIRTIO_VSOCK_TYPE_STREAM,
+ .remote_cid = le32_to_cpu(pkt->hdr.src_cid),
+ .remote_port = le32_to_cpu(pkt->hdr.src_port),
+ };
+ u32 cookie;
+
+ cookie = virtio_vsock_secure_cookie(le32_to_cpu(pkt->hdr.src_cid),
+ le32_to_cpu(pkt->hdr.dst_cid),
+ le32_to_cpu(pkt->hdr.src_port),
+ le32_to_cpu(pkt->hdr.dst_port),
+ jiffies / (HZ * 60));
+ info.flags = cpu_to_le32(cookie);
+
+ pr_debug("%s: send_response, cookie=%x\n", __func__, le32_to_cpu(cookie));
+
+ return trans->ops->send_pkt(vsk, &info);
+}
+
+/* Handle server socket */
+static int
+virtio_transport_recv_listen(struct sock *sk, struct virtio_vsock_pkt *pkt)
+{
+ struct vsock_sock *vsk = vsock_sk(sk);
+ struct vsock_sock *vpending;
+ struct sock *pending;
+ int err;
+ u32 cookie;
+
+ switch (le16_to_cpu(pkt->hdr.op)) {
+ case VIRTIO_VSOCK_OP_REQUEST:
+ err = virtio_transport_send_response(vsk, pkt);
+ if (err < 0) {
+ // FIXME vsk should be vpending
+ virtio_transport_send_reset(vsk, pkt);
+ return err;
+ }
+ break;
+ case VIRTIO_VSOCK_OP_ACK:
+ cookie = le32_to_cpu(pkt->hdr.flags);
+ err = virtio_vsock_check_cookie(le32_to_cpu(pkt->hdr.src_cid),
+ le32_to_cpu(pkt->hdr.dst_cid),
+ le32_to_cpu(pkt->hdr.src_port),
+ le32_to_cpu(pkt->hdr.dst_port),
+ jiffies / (HZ * 60),
+ le32_to_cpu(pkt->hdr.flags),
+ VSOCK_TIMEOUT_INIT);
+ pr_debug("%s: cookie=%x, err=%d\n", __func__, cookie, err);
+ if (err)
+ return err;
+
+ /* So no pending socket are responsible for this pkt, create one */
+ pr_debug("%s: create pending\n", __func__);
+ pending = __vsock_create(sock_net(sk), NULL, sk, GFP_KERNEL,
+ sk->sk_type, 0);
+ if (!pending) {
+ virtio_transport_send_reset(vsk, pkt);
+ return -ENOMEM;
+ }
+ sk->sk_ack_backlog++;
+ pending->sk_state = SS_CONNECTING;
+
+ vpending = vsock_sk(pending);
+ vsock_addr_init(&vpending->local_addr, le32_to_cpu(pkt->hdr.dst_cid),
+ le32_to_cpu(pkt->hdr.dst_port));
+ vsock_addr_init(&vpending->remote_addr, le32_to_cpu(pkt->hdr.src_cid),
+ le32_to_cpu(pkt->hdr.src_port));
+ vsock_add_pending(sk, pending);
+
+ pr_debug("%s: get pending\n", __func__);
+ pending = virtio_transport_get_pending(sk, pkt);
+ vpending = vsock_sk(pending);
+ lock_sock(pending);
+ switch (pending->sk_state) {
+ case SS_CONNECTING:
+ if (le16_to_cpu(pkt->hdr.op) != VIRTIO_VSOCK_OP_ACK) {
+ pr_debug("%s: op=%d != OP_ACK\n", __func__,
+ le16_to_cpu(pkt->hdr.op));
+ virtio_transport_send_reset(vpending, pkt);
+ pending->sk_err = EPROTO;
+ pending->sk_state = SS_UNCONNECTED;
+ sock_put(pending);
+ } else {
+ pending->sk_state = SS_CONNECTED;
+ vsock_insert_connected(vpending);
+
+ vsock_remove_pending(sk, pending);
+ vsock_enqueue_accept(sk, pending);
+
+ sk->sk_data_ready(sk);
+ }
+ err = 0;
+ break;
+ default:
+ pr_debug("%s: sk->sk_ack_backlog=%d\n", __func__,
+ sk->sk_ack_backlog);
+ virtio_transport_send_reset(vpending, pkt);
+ err = -EINVAL;
+ break;
+ }
+ if (err < 0)
+ vsock_remove_pending(sk, pending);
+ release_sock(pending);
+
+ /* Release refcnt obtained in virtio_transport_get_pending */
+ sock_put(pending);
+ break;
+ default:
+ break;
+ }
+
+ return 0;
+}
+
+static void virtio_transport_space_update(struct sock *sk,
+ struct virtio_vsock_pkt *pkt)
+{
+ struct vsock_sock *vsk = vsock_sk(sk);
+ struct virtio_transport *trans = vsk->trans;
+ bool space_available;
+
+ /* buf_alloc and fwd_cnt is always included in the hdr */
+ mutex_lock(&trans->tx_lock);
+ trans->peer_buf_alloc = le32_to_cpu(pkt->hdr.buf_alloc);
+ trans->peer_fwd_cnt = le32_to_cpu(pkt->hdr.fwd_cnt);
+ space_available = virtio_transport_has_space(vsk);
+ mutex_unlock(&trans->tx_lock);
+
+ if (space_available)
+ sk->sk_write_space(sk);
+}
+
+/* We are under the virtio-vsock's vsock->rx_lock or
+ * vhost-vsock's vq->mutex lock */
+void virtio_transport_recv_pkt(struct virtio_vsock_pkt *pkt)
+{
+ struct virtio_transport *trans;
+ struct sockaddr_vm src, dst;
+ struct vsock_sock *vsk;
+ struct sock *sk;
+
+ vsock_addr_init(&src, le32_to_cpu(pkt->hdr.src_cid), le32_to_cpu(pkt->hdr.src_port));
+ vsock_addr_init(&dst, le32_to_cpu(pkt->hdr.dst_cid), le32_to_cpu(pkt->hdr.dst_port));
+
+ virtio_vsock_dumppkt(__func__, pkt);
+
+ if (le16_to_cpu(pkt->hdr.type) == VIRTIO_VSOCK_TYPE_DGRAM) {
+ sk = vsock_find_unbound_socket(&dst);
+ if (!sk)
+ goto free_pkt;
+
+ vsk = vsock_sk(sk);
+ trans = vsk->trans;
+ BUG_ON(!trans);
+
+ virtio_transport_space_update(sk, pkt);
+
+ lock_sock(sk);
+ switch (le16_to_cpu(pkt->hdr.op)) {
+ case VIRTIO_VSOCK_OP_CREDIT_UPDATE:
+ virtio_transport_free_pkt(pkt);
+ break;
+ case VIRTIO_VSOCK_OP_CREDIT_REQUEST:
+ virtio_transport_send_credit_update(vsk, VIRTIO_VSOCK_TYPE_DGRAM,
+ &pkt->hdr);
+ virtio_transport_free_pkt(pkt);
+ break;
+ case VIRTIO_VSOCK_OP_RW:
+ virtio_transport_recv_dgram(sk, pkt);
+ break;
+ default:
+ virtio_transport_free_pkt(pkt);
+ break;
+ }
+ release_sock(sk);
+
+ /* Release refcnt obtained when we fetched this socket out of
+ * the unbound list.
+ */
+ sock_put(sk);
+ return;
+ } else if (le16_to_cpu(pkt->hdr.type) == VIRTIO_VSOCK_TYPE_STREAM) {
+ /* The socket must be in connected or bound table
+ * otherwise send reset back
+ */
+ sk = vsock_find_connected_socket(&src, &dst);
+ if (!sk) {
+ sk = vsock_find_bound_socket(&dst);
+ if (!sk) {
+ pr_debug("%s: can not find bound_socket\n", __func__);
+ virtio_vsock_dumppkt(__func__, pkt);
+ /* Ignore this pkt instead of sending reset back */
+ /* TODO send a RST unless this packet is a RST (to avoid infinite loops) */
+ goto free_pkt;
+ }
+ }
+
+ vsk = vsock_sk(sk);
+ trans = vsk->trans;
+ BUG_ON(!trans);
+
+ virtio_transport_space_update(sk, pkt);
+
+ lock_sock(sk);
+ switch (sk->sk_state) {
+ case VSOCK_SS_LISTEN:
+ virtio_transport_recv_listen(sk, pkt);
+ virtio_transport_free_pkt(pkt);
+ break;
+ case SS_CONNECTING:
+ virtio_transport_recv_connecting(sk, pkt);
+ virtio_transport_free_pkt(pkt);
+ break;
+ case SS_CONNECTED:
+ virtio_transport_recv_connected(sk, pkt);
+ break;
+ default:
+ virtio_transport_free_pkt(pkt);
+ break;
+ }
+ release_sock(sk);
+
+ /* Release refcnt obtained when we fetched this socket out of the
+ * bound or connected list.
+ */
+ sock_put(sk);
+ }
+ return;
+
+free_pkt:
+ virtio_transport_free_pkt(pkt);
+}
+EXPORT_SYMBOL_GPL(virtio_transport_recv_pkt);
+
+void virtio_transport_free_pkt(struct virtio_vsock_pkt *pkt)
+{
+ kfree(pkt->buf);
+ kfree(pkt);
+}
+EXPORT_SYMBOL_GPL(virtio_transport_free_pkt);
+
+static int __init virtio_vsock_common_init(void)
+{
+ get_random_bytes(vsockcookie_secret, sizeof(vsockcookie_secret));
+ return 0;
+}
+
+static void __exit virtio_vsock_common_exit(void)
+{
+}
+
+module_init(virtio_vsock_common_init);
+module_exit(virtio_vsock_common_exit);
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Asias He");
+MODULE_DESCRIPTION("common code for virtio vsock");