Orange Pi5 kernel

// SPDX-License-Identifier: GPL-2.0-only
/*
 * common code for virtio vsock
 *
 * Copyright (C) 2013-2015 Red Hat, Inc.
 * Author: Asias He <asias@redhat.com>
 *         Stefan Hajnoczi <stefanha@redhat.com>
 */
#include <linux/spinlock.h>
#include <linux/module.h>
#include <linux/sched/signal.h>
#include <linux/ctype.h>
#include <linux/list.h>
#include <linux/virtio_vsock.h>
#include <uapi/linux/vsockmon.h>
 
#include <net/sock.h>
#include <net/af_vsock.h>
 
#define CREATE_TRACE_POINTS
#include <trace/events/vsock_virtio_transport_common.h>
 
/* How long to wait for graceful shutdown of a connection */
#define VSOCK_CLOSE_TIMEOUT (8 * HZ)
 
/* Threshold for detecting small packets to copy */
#define GOOD_COPY_LEN  128
 
uint virtio_transport_max_vsock_pkt_buf_size = 64 * 1024;
module_param(virtio_transport_max_vsock_pkt_buf_size, uint, 0444);
EXPORT_SYMBOL_GPL(virtio_transport_max_vsock_pkt_buf_size);
 
static const struct virtio_transport *
virtio_transport_get_ops(struct vsock_sock *vsk)
{
<------>const struct vsock_transport *t = vsock_core_get_transport(vsk);
 
<------>if (WARN_ON(!t))
<------><------>return NULL;
 
<------>return container_of(t, struct virtio_transport, transport);
}
 
static struct virtio_vsock_pkt *
virtio_transport_alloc_pkt(struct virtio_vsock_pkt_info *info,
<------><------><------>   size_t len,
<------><------><------>   u32 src_cid,
<------><------><------>   u32 src_port,
<------><------><------>   u32 dst_cid,
<------><------><------>   u32 dst_port)
{
<------>struct virtio_vsock_pkt *pkt;
<------>int err;
 
<------>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_le64(src_cid);
<------>pkt->hdr.dst_cid	= cpu_to_le64(dst_cid);
<------>pkt->hdr.src_port	= cpu_to_le32(src_port);
<------>pkt->hdr.dst_port	= cpu_to_le32(dst_port);
<------>pkt->hdr.flags		= cpu_to_le32(info->flags);
<------>pkt->len		= len;
<------>pkt->hdr.len		= cpu_to_le32(len);
<------>pkt->reply		= info->reply;
<------>pkt->vsk		= info->vsk;
 
<------>if (info->msg && len > 0) {
<------><------>pkt->buf = kmalloc(len, GFP_KERNEL);
<------><------>if (!pkt->buf)
<------><------><------>goto out_pkt;
 
<------><------>pkt->buf_len = len;
 
<------><------>err = memcpy_from_msg(pkt->buf, info->msg, len);
<------><------>if (err)
<------><------><------>goto out;
<------>}
 
<------>trace_virtio_transport_alloc_pkt(src_cid, src_port,
<------><------><------><------><------> dst_cid, dst_port,
<------><------><------><------><------> len,
<------><------><------><------><------> info->type,
<------><------><------><------><------> info->op,
<------><------><------><------><------> info->flags);
 
<------>return pkt;
 
out:
<------>kfree(pkt->buf);
out_pkt:
<------>kfree(pkt);
<------>return NULL;
}
 
/* Packet capture */
static struct sk_buff *virtio_transport_build_skb(void *opaque)
{
<------>struct virtio_vsock_pkt *pkt = opaque;
<------>struct af_vsockmon_hdr *hdr;
<------>struct sk_buff *skb;
<------>size_t payload_len;
<------>void *payload_buf;
 
<------>/* A packet could be split to fit the RX buffer, so we can retrieve
<------> * the payload length from the header and the buffer pointer taking
<------> * care of the offset in the original packet.
<------> */
<------>payload_len = le32_to_cpu(pkt->hdr.len);
<------>payload_buf = pkt->buf + pkt->off;
 
<------>skb = alloc_skb(sizeof(*hdr) + sizeof(pkt->hdr) + payload_len,
<------><------><------>GFP_ATOMIC);
<------>if (!skb)
<------><------>return NULL;
 
<------>hdr = skb_put(skb, sizeof(*hdr));
 
<------>/* pkt->hdr is little-endian so no need to byteswap here */
<------>hdr->src_cid = pkt->hdr.src_cid;
<------>hdr->src_port = pkt->hdr.src_port;
<------>hdr->dst_cid = pkt->hdr.dst_cid;
<------>hdr->dst_port = pkt->hdr.dst_port;
 
<------>hdr->transport = cpu_to_le16(AF_VSOCK_TRANSPORT_VIRTIO);
<------>hdr->len = cpu_to_le16(sizeof(pkt->hdr));
<------>memset(hdr->reserved, 0, sizeof(hdr->reserved));
 
<------>switch (le16_to_cpu(pkt->hdr.op)) {
<------>case VIRTIO_VSOCK_OP_REQUEST:
<------>case VIRTIO_VSOCK_OP_RESPONSE:
<------><------>hdr->op = cpu_to_le16(AF_VSOCK_OP_CONNECT);
<------><------>break;
<------>case VIRTIO_VSOCK_OP_RST:
<------>case VIRTIO_VSOCK_OP_SHUTDOWN:
<------><------>hdr->op = cpu_to_le16(AF_VSOCK_OP_DISCONNECT);
<------><------>break;
<------>case VIRTIO_VSOCK_OP_RW:
<------><------>hdr->op = cpu_to_le16(AF_VSOCK_OP_PAYLOAD);
<------><------>break;
<------>case VIRTIO_VSOCK_OP_CREDIT_UPDATE:
<------>case VIRTIO_VSOCK_OP_CREDIT_REQUEST:
<------><------>hdr->op = cpu_to_le16(AF_VSOCK_OP_CONTROL);
<------><------>break;
<------>default:
<------><------>hdr->op = cpu_to_le16(AF_VSOCK_OP_UNKNOWN);
<------><------>break;
<------>}
 
<------>skb_put_data(skb, &pkt->hdr, sizeof(pkt->hdr));
 
<------>if (payload_len) {
<------><------>skb_put_data(skb, payload_buf, payload_len);
<------>}
 
<------>return skb;
}
 
void virtio_transport_deliver_tap_pkt(struct virtio_vsock_pkt *pkt)
{
<------>if (pkt->tap_delivered)
<------><------>return;
 
<------>vsock_deliver_tap(virtio_transport_build_skb, pkt);
<------>pkt->tap_delivered = true;
}
EXPORT_SYMBOL_GPL(virtio_transport_deliver_tap_pkt);
 
/* This function can only be used on connecting/connected sockets,
 * since a socket assigned to a transport is required.
 *
 * Do not use on listener sockets!
 */
static int virtio_transport_send_pkt_info(struct vsock_sock *vsk,
<------><------><------><------><------>  struct virtio_vsock_pkt_info *info)
{
<------>u32 src_cid, src_port, dst_cid, dst_port;
<------>const struct virtio_transport *t_ops;
<------>struct virtio_vsock_sock *vvs;
<------>struct virtio_vsock_pkt *pkt;
<------>u32 pkt_len = info->pkt_len;
 
<------>t_ops = virtio_transport_get_ops(vsk);
<------>if (unlikely(!t_ops))
<------><------>return -EFAULT;
 
<------>src_cid = t_ops->transport.get_local_cid();
<------>src_port = vsk->local_addr.svm_port;
<------>if (!info->remote_cid) {
<------><------>dst_cid	= vsk->remote_addr.svm_cid;
<------><------>dst_port = vsk->remote_addr.svm_port;
<------>} else {
<------><------>dst_cid = info->remote_cid;
<------><------>dst_port = info->remote_port;
<------>}
 
<------>vvs = vsk->trans;
 
<------>/* we can send less than pkt_len bytes */
<------>if (pkt_len > VIRTIO_VSOCK_MAX_PKT_BUF_SIZE)
<------><------>pkt_len = VIRTIO_VSOCK_MAX_PKT_BUF_SIZE;
 
<------>/* virtio_transport_get_credit might return less than pkt_len credit */
<------>pkt_len = virtio_transport_get_credit(vvs, pkt_len);
 
<------>/* Do not send zero length OP_RW pkt */
<------>if (pkt_len == 0 && info->op == VIRTIO_VSOCK_OP_RW)
<------><------>return pkt_len;
 
<------>pkt = virtio_transport_alloc_pkt(info, pkt_len,
<------><------><------><------><------> src_cid, src_port,
<------><------><------><------><------> dst_cid, dst_port);
<------>if (!pkt) {
<------><------>virtio_transport_put_credit(vvs, pkt_len);
<------><------>return -ENOMEM;
<------>}
 
<------>virtio_transport_inc_tx_pkt(vvs, pkt);
 
<------>return t_ops->send_pkt(pkt);
}
 
static bool virtio_transport_inc_rx_pkt(struct virtio_vsock_sock *vvs,
<------><------><------><------><------>struct virtio_vsock_pkt *pkt)
{
<------>if (vvs->rx_bytes + pkt->len > vvs->buf_alloc)
<------><------>return false;
 
<------>vvs->rx_bytes += pkt->len;
<------>return true;
}
 
static void virtio_transport_dec_rx_pkt(struct virtio_vsock_sock *vvs,
<------><------><------><------><------>struct virtio_vsock_pkt *pkt)
{
<------>vvs->rx_bytes -= pkt->len;
<------>vvs->fwd_cnt += pkt->len;
}
 
void virtio_transport_inc_tx_pkt(struct virtio_vsock_sock *vvs, struct virtio_vsock_pkt *pkt)
{
<------>spin_lock_bh(&vvs->rx_lock);
<------>vvs->last_fwd_cnt = vvs->fwd_cnt;
<------>pkt->hdr.fwd_cnt = cpu_to_le32(vvs->fwd_cnt);
<------>pkt->hdr.buf_alloc = cpu_to_le32(vvs->buf_alloc);
<------>spin_unlock_bh(&vvs->rx_lock);
}
EXPORT_SYMBOL_GPL(virtio_transport_inc_tx_pkt);
 
u32 virtio_transport_get_credit(struct virtio_vsock_sock *vvs, u32 credit)
{
<------>u32 ret;
 
<------>spin_lock_bh(&vvs->tx_lock);
<------>ret = vvs->peer_buf_alloc - (vvs->tx_cnt - vvs->peer_fwd_cnt);
<------>if (ret > credit)
<------><------>ret = credit;
<------>vvs->tx_cnt += ret;
<------>spin_unlock_bh(&vvs->tx_lock);
 
<------>return ret;
}
EXPORT_SYMBOL_GPL(virtio_transport_get_credit);
 
void virtio_transport_put_credit(struct virtio_vsock_sock *vvs, u32 credit)
{
<------>spin_lock_bh(&vvs->tx_lock);
<------>vvs->tx_cnt -= credit;
<------>spin_unlock_bh(&vvs->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_vsock_pkt_info info = {
<------><------>.op = VIRTIO_VSOCK_OP_CREDIT_UPDATE,
<------><------>.type = type,
<------><------>.vsk = vsk,
<------>};
 
<------>return virtio_transport_send_pkt_info(vsk, &info);
}
 
static ssize_t
virtio_transport_stream_do_peek(struct vsock_sock *vsk,
<------><------><------><------>struct msghdr *msg,
<------><------><------><------>size_t len)
{
<------>struct virtio_vsock_sock *vvs = vsk->trans;
<------>struct virtio_vsock_pkt *pkt;
<------>size_t bytes, total = 0, off;
<------>int err = -EFAULT;
 
<------>spin_lock_bh(&vvs->rx_lock);
 
<------>list_for_each_entry(pkt, &vvs->rx_queue, list) {
<------><------>off = pkt->off;
 
<------><------>if (total == len)
<------><------><------>break;
 
<------><------>while (total < len && off < pkt->len) {
<------><------><------>bytes = len - total;
<------><------><------>if (bytes > pkt->len - off)
<------><------><------><------>bytes = pkt->len - off;
 
<------><------><------>/* sk_lock is held by caller so no one else can dequeue.
<------><------><------> * Unlock rx_lock since memcpy_to_msg() may sleep.
<------><------><------> */
<------><------><------>spin_unlock_bh(&vvs->rx_lock);
 
<------><------><------>err = memcpy_to_msg(msg, pkt->buf + off, bytes);
<------><------><------>if (err)
<------><------><------><------>goto out;
 
<------><------><------>spin_lock_bh(&vvs->rx_lock);
 
<------><------><------>total += bytes;
<------><------><------>off += bytes;
<------><------>}
<------>}
 
<------>spin_unlock_bh(&vvs->rx_lock);
 
<------>return total;
 
out:
<------>if (total)
<------><------>err = total;
<------>return err;
}
 
static ssize_t
virtio_transport_stream_do_dequeue(struct vsock_sock *vsk,
<------><------><------><------>   struct msghdr *msg,
<------><------><------><------>   size_t len)
{
<------>struct virtio_vsock_sock *vvs = vsk->trans;
<------>struct virtio_vsock_pkt *pkt;
<------>size_t bytes, total = 0;
<------>u32 free_space;
<------>int err = -EFAULT;
 
<------>spin_lock_bh(&vvs->rx_lock);
<------>while (total < len && !list_empty(&vvs->rx_queue)) {
<------><------>pkt = list_first_entry(&vvs->rx_queue,
<------><------><------><------>       struct virtio_vsock_pkt, list);
 
<------><------>bytes = len - total;
<------><------>if (bytes > pkt->len - pkt->off)
<------><------><------>bytes = pkt->len - pkt->off;
 
<------><------>/* sk_lock is held by caller so no one else can dequeue.
<------><------> * Unlock rx_lock since memcpy_to_msg() may sleep.
<------><------> */
<------><------>spin_unlock_bh(&vvs->rx_lock);
 
<------><------>err = memcpy_to_msg(msg, pkt->buf + pkt->off, bytes);
<------><------>if (err)
<------><------><------>goto out;
 
<------><------>spin_lock_bh(&vvs->rx_lock);
 
<------><------>total += bytes;
<------><------>pkt->off += bytes;
<------><------>if (pkt->off == pkt->len) {
<------><------><------>virtio_transport_dec_rx_pkt(vvs, pkt);
<------><------><------>list_del(&pkt->list);
<------><------><------>virtio_transport_free_pkt(pkt);
<------><------>}
<------>}
 
<------>free_space = vvs->buf_alloc - (vvs->fwd_cnt - vvs->last_fwd_cnt);
 
<------>spin_unlock_bh(&vvs->rx_lock);
 
<------>/* To reduce the number of credit update messages,
<------> * don't update credits as long as lots of space is available.
<------> * Note: the limit chosen here is arbitrary. Setting the limit
<------> * too high causes extra messages. Too low causes transmitter
<------> * stalls. As stalls are in theory more expensive than extra
<------> * messages, we set the limit to a high value. TODO: experiment
<------> * with different values.
<------> */
<------>if (free_space < VIRTIO_VSOCK_MAX_PKT_BUF_SIZE) {
<------><------>virtio_transport_send_credit_update(vsk,
<------><------><------><------><------><------>    VIRTIO_VSOCK_TYPE_STREAM,
<------><------><------><------><------><------>    NULL);
<------>}
 
<------>return total;
 
out:
<------>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 virtio_transport_stream_do_peek(vsk, msg, len);
<------>else
<------><------>return virtio_transport_stream_do_dequeue(vsk, msg, len);
}
EXPORT_SYMBOL_GPL(virtio_transport_stream_dequeue);
 
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;
<------>s64 bytes;
 
<------>spin_lock_bh(&vvs->rx_lock);
<------>bytes = vvs->rx_bytes;
<------>spin_unlock_bh(&vvs->rx_lock);
 
<------>return bytes;
}
EXPORT_SYMBOL_GPL(virtio_transport_stream_has_data);
 
static s64 virtio_transport_has_space(struct vsock_sock *vsk)
{
<------>struct virtio_vsock_sock *vvs = vsk->trans;
<------>s64 bytes;
 
<------>bytes = vvs->peer_buf_alloc - (vvs->tx_cnt - vvs->peer_fwd_cnt);
<------>if (bytes < 0)
<------><------>bytes = 0;
 
<------>return bytes;
}
 
s64 virtio_transport_stream_has_space(struct vsock_sock *vsk)
{
<------>struct virtio_vsock_sock *vvs = vsk->trans;
<------>s64 bytes;
 
<------>spin_lock_bh(&vvs->tx_lock);
<------>bytes = virtio_transport_has_space(vsk);
<------>spin_unlock_bh(&vvs->tx_lock);
 
<------>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_vsock_sock *vvs;
 
<------>vvs = kzalloc(sizeof(*vvs), GFP_KERNEL);
<------>if (!vvs)
<------><------>return -ENOMEM;
 
<------>vsk->trans = vvs;
<------>vvs->vsk = vsk;
<------>if (psk && psk->trans) {
<------><------>struct virtio_vsock_sock *ptrans = psk->trans;
 
<------><------>vvs->peer_buf_alloc = ptrans->peer_buf_alloc;
<------>}
 
<------>if (vsk->buffer_size > VIRTIO_VSOCK_MAX_BUF_SIZE)
<------><------>vsk->buffer_size = VIRTIO_VSOCK_MAX_BUF_SIZE;
 
<------>vvs->buf_alloc = vsk->buffer_size;
 
<------>spin_lock_init(&vvs->rx_lock);
<------>spin_lock_init(&vvs->tx_lock);
<------>INIT_LIST_HEAD(&vvs->rx_queue);
 
<------>return 0;
}
EXPORT_SYMBOL_GPL(virtio_transport_do_socket_init);
 
/* sk_lock held by the caller */
void virtio_transport_notify_buffer_size(struct vsock_sock *vsk, u64 *val)
{
<------>struct virtio_vsock_sock *vvs = vsk->trans;
 
<------>if (*val > VIRTIO_VSOCK_MAX_BUF_SIZE)
<------><------>*val = VIRTIO_VSOCK_MAX_BUF_SIZE;
 
<------>vvs->buf_alloc = *val;
 
<------>virtio_transport_send_credit_update(vsk, VIRTIO_VSOCK_TYPE_STREAM,
<------><------><------><------><------>    NULL);
}
EXPORT_SYMBOL_GPL(virtio_transport_notify_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)
{
<------>return vsk->buffer_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 -EOPNOTSUPP;
}
EXPORT_SYMBOL_GPL(virtio_transport_dgram_bind);
 
bool virtio_transport_dgram_allow(u32 cid, u32 port)
{
<------>return false;
}
EXPORT_SYMBOL_GPL(virtio_transport_dgram_allow);
 
int virtio_transport_connect(struct vsock_sock *vsk)
{
<------>struct virtio_vsock_pkt_info info = {
<------><------>.op = VIRTIO_VSOCK_OP_REQUEST,
<------><------>.type = VIRTIO_VSOCK_TYPE_STREAM,
<------><------>.vsk = vsk,
<------>};
 
<------>return virtio_transport_send_pkt_info(vsk, &info);
}
EXPORT_SYMBOL_GPL(virtio_transport_connect);
 
int virtio_transport_shutdown(struct vsock_sock *vsk, int mode)
{
<------>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),
<------><------>.vsk = vsk,
<------>};
 
<------>return virtio_transport_send_pkt_info(vsk, &info);
}
EXPORT_SYMBOL_GPL(virtio_transport_shutdown);
 
int
virtio_transport_dgram_enqueue(struct vsock_sock *vsk,
<------><------><------>       struct sockaddr_vm *remote_addr,
<------><------><------>       struct msghdr *msg,
<------><------><------>       size_t dgram_len)
{
<------>return -EOPNOTSUPP;
}
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_vsock_pkt_info info = {
<------><------>.op = VIRTIO_VSOCK_OP_RW,
<------><------>.type = VIRTIO_VSOCK_TYPE_STREAM,
<------><------>.msg = msg,
<------><------>.pkt_len = len,
<------><------>.vsk = vsk,
<------>};
 
<------>return virtio_transport_send_pkt_info(vsk, &info);
}
EXPORT_SYMBOL_GPL(virtio_transport_stream_enqueue);
 
void virtio_transport_destruct(struct vsock_sock *vsk)
{
<------>struct virtio_vsock_sock *vvs = vsk->trans;
 
<------>kfree(vvs);
}
EXPORT_SYMBOL_GPL(virtio_transport_destruct);
 
static int virtio_transport_reset(struct vsock_sock *vsk,
<------><------><------><------>  struct virtio_vsock_pkt *pkt)
{
<------>struct virtio_vsock_pkt_info info = {
<------><------>.op = VIRTIO_VSOCK_OP_RST,
<------><------>.type = VIRTIO_VSOCK_TYPE_STREAM,
<------><------>.reply = !!pkt,
<------><------>.vsk = vsk,
<------>};
 
<------>/* Send RST only if the original pkt is not a RST pkt */
<------>if (pkt && le16_to_cpu(pkt->hdr.op) == VIRTIO_VSOCK_OP_RST)
<------><------>return 0;
 
<------>return virtio_transport_send_pkt_info(vsk, &info);
}
 
/* Normally packets are associated with a socket.  There may be no socket if an
 * attempt was made to connect to a socket that does not exist.
 */
static int virtio_transport_reset_no_sock(const struct virtio_transport *t,
<------><------><------><------><------>  struct virtio_vsock_pkt *pkt)
{
<------>struct virtio_vsock_pkt *reply;
<------>struct virtio_vsock_pkt_info info = {
<------><------>.op = VIRTIO_VSOCK_OP_RST,
<------><------>.type = le16_to_cpu(pkt->hdr.type),
<------><------>.reply = true,
<------>};
 
<------>/* 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;
 
<------>reply = virtio_transport_alloc_pkt(&info, 0,
<------><------><------><------><------>   le64_to_cpu(pkt->hdr.dst_cid),
<------><------><------><------><------>   le32_to_cpu(pkt->hdr.dst_port),
<------><------><------><------><------>   le64_to_cpu(pkt->hdr.src_cid),
<------><------><------><------><------>   le32_to_cpu(pkt->hdr.src_port));
<------>if (!reply)
<------><------>return -ENOMEM;
 
<------>if (!t) {
<------><------>virtio_transport_free_pkt(reply);
<------><------>return -ENOTCONN;
<------>}
 
<------>return t->send_pkt(reply);
}
 
/* This function should be called with sk_lock held and SOCK_DONE set */
static void virtio_transport_remove_sock(struct vsock_sock *vsk)
{
<------>struct virtio_vsock_sock *vvs = vsk->trans;
<------>struct virtio_vsock_pkt *pkt, *tmp;
 
<------>/* We don't need to take rx_lock, as the socket is closing and we are
<------> * removing it.
<------> */
<------>list_for_each_entry_safe(pkt, tmp, &vvs->rx_queue, list) {
<------><------>list_del(&pkt->list);
<------><------>virtio_transport_free_pkt(pkt);
<------>}
 
<------>vsock_remove_sock(vsk);
}
 
static void virtio_transport_wait_close(struct sock *sk, long timeout)
{
<------>if (timeout) {
<------><------>DEFINE_WAIT_FUNC(wait, woken_wake_function);
 
<------><------>add_wait_queue(sk_sleep(sk), &wait);
 
<------><------>do {
<------><------><------>if (sk_wait_event(sk, &timeout,
<------><------><------><------><------>  sock_flag(sk, SOCK_DONE), &wait))
<------><------><------><------>break;
<------><------>} while (!signal_pending(current) && timeout);
 
<------><------>remove_wait_queue(sk_sleep(sk), &wait);
<------>}
}
 
static void virtio_transport_do_close(struct vsock_sock *vsk,
<------><------><------><------>      bool cancel_timeout)
{
<------>struct sock *sk = sk_vsock(vsk);
 
<------>sock_set_flag(sk, SOCK_DONE);
<------>vsk->peer_shutdown = SHUTDOWN_MASK;
<------>if (vsock_stream_has_data(vsk) <= 0)
<------><------>sk->sk_state = TCP_CLOSING;
<------>sk->sk_state_change(sk);
 
<------>if (vsk->close_work_scheduled &&
<------>    (!cancel_timeout || cancel_delayed_work(&vsk->close_work))) {
<------><------>vsk->close_work_scheduled = false;
 
<------><------>virtio_transport_remove_sock(vsk);
 
<------><------>/* Release refcnt obtained when we scheduled the timeout */
<------><------>sock_put(sk);
<------>}
}
 
static void virtio_transport_close_timeout(struct work_struct *work)
{
<------>struct vsock_sock *vsk =
<------><------>container_of(work, struct vsock_sock, close_work.work);
<------>struct sock *sk = sk_vsock(vsk);
 
<------>sock_hold(sk);
<------>lock_sock(sk);
 
<------>if (!sock_flag(sk, SOCK_DONE)) {
<------><------>(void)virtio_transport_reset(vsk, NULL);
 
<------><------>virtio_transport_do_close(vsk, false);
<------>}
 
<------>vsk->close_work_scheduled = false;
 
<------>release_sock(sk);
<------>sock_put(sk);
}
 
/* User context, vsk->sk is locked */
static bool virtio_transport_close(struct vsock_sock *vsk)
{
<------>struct sock *sk = &vsk->sk;
 
<------>if (!(sk->sk_state == TCP_ESTABLISHED ||
<------>      sk->sk_state == TCP_CLOSING))
<------><------>return true;
 
<------>/* Already received SHUTDOWN from peer, reply with RST */
<------>if ((vsk->peer_shutdown & SHUTDOWN_MASK) == SHUTDOWN_MASK) {
<------><------>(void)virtio_transport_reset(vsk, NULL);
<------><------>return true;
<------>}
 
<------>if ((sk->sk_shutdown & SHUTDOWN_MASK) != SHUTDOWN_MASK)
<------><------>(void)virtio_transport_shutdown(vsk, SHUTDOWN_MASK);
 
<------>if (sock_flag(sk, SOCK_LINGER) && !(current->flags & PF_EXITING))
<------><------>virtio_transport_wait_close(sk, sk->sk_lingertime);
 
<------>if (sock_flag(sk, SOCK_DONE)) {
<------><------>return true;
<------>}
 
<------>sock_hold(sk);
<------>INIT_DELAYED_WORK(&vsk->close_work,
<------><------><------>  virtio_transport_close_timeout);
<------>vsk->close_work_scheduled = true;
<------>schedule_delayed_work(&vsk->close_work, VSOCK_CLOSE_TIMEOUT);
<------>return false;
}
 
void virtio_transport_release(struct vsock_sock *vsk)
{
<------>struct sock *sk = &vsk->sk;
<------>bool remove_sock = true;
 
<------>if (sk->sk_type == SOCK_STREAM)
<------><------>remove_sock = virtio_transport_close(vsk);
 
<------>if (remove_sock) {
<------><------>sock_set_flag(sk, SOCK_DONE);
<------><------>virtio_transport_remove_sock(vsk);
<------>}
}
EXPORT_SYMBOL_GPL(virtio_transport_release);
 
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;
 
<------>switch (le16_to_cpu(pkt->hdr.op)) {
<------>case VIRTIO_VSOCK_OP_RESPONSE:
<------><------>sk->sk_state = TCP_ESTABLISHED;
<------><------>sk->sk_socket->state = SS_CONNECTED;
<------><------>vsock_insert_connected(vsk);
<------><------>sk->sk_state_change(sk);
<------><------>break;
<------>case VIRTIO_VSOCK_OP_INVALID:
<------><------>break;
<------>case VIRTIO_VSOCK_OP_RST:
<------><------>skerr = ECONNRESET;
<------><------>err = 0;
<------><------>goto destroy;
<------>default:
<------><------>skerr = EPROTO;
<------><------>err = -EINVAL;
<------><------>goto destroy;
<------>}
<------>return 0;
 
destroy:
<------>virtio_transport_reset(vsk, pkt);
<------>sk->sk_state = TCP_CLOSE;
<------>sk->sk_err = skerr;
<------>sk->sk_error_report(sk);
<------>return err;
}
 
static void
virtio_transport_recv_enqueue(struct vsock_sock *vsk,
<------><------><------>      struct virtio_vsock_pkt *pkt)
{
<------>struct virtio_vsock_sock *vvs = vsk->trans;
<------>bool can_enqueue, free_pkt = false;
 
<------>pkt->len = le32_to_cpu(pkt->hdr.len);
<------>pkt->off = 0;
 
<------>spin_lock_bh(&vvs->rx_lock);
 
<------>can_enqueue = virtio_transport_inc_rx_pkt(vvs, pkt);
<------>if (!can_enqueue) {
<------><------>free_pkt = true;
<------><------>goto out;
<------>}
 
<------>/* Try to copy small packets into the buffer of last packet queued,
<------> * to avoid wasting memory queueing the entire buffer with a small
<------> * payload.
<------> */
<------>if (pkt->len <= GOOD_COPY_LEN && !list_empty(&vvs->rx_queue)) {
<------><------>struct virtio_vsock_pkt *last_pkt;
 
<------><------>last_pkt = list_last_entry(&vvs->rx_queue,
<------><------><------><------><------>   struct virtio_vsock_pkt, list);
 
<------><------>/* If there is space in the last packet queued, we copy the
<------><------> * new packet in its buffer.
<------><------> */
<------><------>if (pkt->len <= last_pkt->buf_len - last_pkt->len) {
<------><------><------>memcpy(last_pkt->buf + last_pkt->len, pkt->buf,
<------><------><------>       pkt->len);
<------><------><------>last_pkt->len += pkt->len;
<------><------><------>free_pkt = true;
<------><------><------>goto out;
<------><------>}
<------>}
 
<------>list_add_tail(&pkt->list, &vvs->rx_queue);
 
out:
<------>spin_unlock_bh(&vvs->rx_lock);
<------>if (free_pkt)
<------><------>virtio_transport_free_pkt(pkt);
}
 
static int
virtio_transport_recv_connected(struct sock *sk,
<------><------><------><------>struct virtio_vsock_pkt *pkt)
{
<------>struct vsock_sock *vsk = vsock_sk(sk);
<------>int err = 0;
 
<------>switch (le16_to_cpu(pkt->hdr.op)) {
<------>case VIRTIO_VSOCK_OP_RW:
<------><------>virtio_transport_recv_enqueue(vsk, pkt);
<------><------>sk->sk_data_ready(sk);
<------><------>return err;
<------>case VIRTIO_VSOCK_OP_CREDIT_UPDATE:
<------><------>sk->sk_write_space(sk);
<------><------>break;
<------>case VIRTIO_VSOCK_OP_SHUTDOWN:
<------><------>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 (vsk->peer_shutdown == SHUTDOWN_MASK &&
<------><------>    vsock_stream_has_data(vsk) <= 0 &&
<------><------>    !sock_flag(sk, SOCK_DONE)) {
<------><------><------>(void)virtio_transport_reset(vsk, NULL);
 
<------><------><------>virtio_transport_do_close(vsk, true);
<------><------>}
<------><------>if (le32_to_cpu(pkt->hdr.flags))
<------><------><------>sk->sk_state_change(sk);
<------><------>break;
<------>case VIRTIO_VSOCK_OP_RST:
<------><------>virtio_transport_do_close(vsk, true);
<------><------>break;
<------>default:
<------><------>err = -EINVAL;
<------><------>break;
<------>}
 
<------>virtio_transport_free_pkt(pkt);
<------>return err;
}
 
static void
virtio_transport_recv_disconnecting(struct sock *sk,
<------><------><------><------>    struct virtio_vsock_pkt *pkt)
{
<------>struct vsock_sock *vsk = vsock_sk(sk);
 
<------>if (le16_to_cpu(pkt->hdr.op) == VIRTIO_VSOCK_OP_RST)
<------><------>virtio_transport_do_close(vsk, true);
}
 
static int
virtio_transport_send_response(struct vsock_sock *vsk,
<------><------><------>       struct virtio_vsock_pkt *pkt)
{
<------>struct virtio_vsock_pkt_info info = {
<------><------>.op = VIRTIO_VSOCK_OP_RESPONSE,
<------><------>.type = VIRTIO_VSOCK_TYPE_STREAM,
<------><------>.remote_cid = le64_to_cpu(pkt->hdr.src_cid),
<------><------>.remote_port = le32_to_cpu(pkt->hdr.src_port),
<------><------>.reply = true,
<------><------>.vsk = vsk,
<------>};
 
<------>return virtio_transport_send_pkt_info(vsk, &info);
}
 
static bool virtio_transport_space_update(struct sock *sk,
<------><------><------><------><------>  struct virtio_vsock_pkt *pkt)
{
<------>struct vsock_sock *vsk = vsock_sk(sk);
<------>struct virtio_vsock_sock *vvs = vsk->trans;
<------>bool space_available;
 
<------>/* Listener sockets are not associated with any transport, so we are
<------> * not able to take the state to see if there is space available in the
<------> * remote peer, but since they are only used to receive requests, we
<------> * can assume that there is always space available in the other peer.
<------> */
<------>if (!vvs)
<------><------>return true;
 
<------>/* buf_alloc and fwd_cnt is always included in the hdr */
<------>spin_lock_bh(&vvs->tx_lock);
<------>vvs->peer_buf_alloc = le32_to_cpu(pkt->hdr.buf_alloc);
<------>vvs->peer_fwd_cnt = le32_to_cpu(pkt->hdr.fwd_cnt);
<------>space_available = virtio_transport_has_space(vsk);
<------>spin_unlock_bh(&vvs->tx_lock);
<------>return space_available;
}
 
/* Handle server socket */
static int
virtio_transport_recv_listen(struct sock *sk, struct virtio_vsock_pkt *pkt,
<------><------><------>     struct virtio_transport *t)
{
<------>struct vsock_sock *vsk = vsock_sk(sk);
<------>struct vsock_sock *vchild;
<------>struct sock *child;
<------>int ret;
 
<------>if (le16_to_cpu(pkt->hdr.op) != VIRTIO_VSOCK_OP_REQUEST) {
<------><------>virtio_transport_reset_no_sock(t, pkt);
<------><------>return -EINVAL;
<------>}
 
<------>if (sk_acceptq_is_full(sk)) {
<------><------>virtio_transport_reset_no_sock(t, pkt);
<------><------>return -ENOMEM;
<------>}
 
<------>child = vsock_create_connected(sk);
<------>if (!child) {
<------><------>virtio_transport_reset_no_sock(t, pkt);
<------><------>return -ENOMEM;
<------>}
 
<------>sk_acceptq_added(sk);
 
<------>lock_sock_nested(child, SINGLE_DEPTH_NESTING);
 
<------>child->sk_state = TCP_ESTABLISHED;
 
<------>vchild = vsock_sk(child);
<------>vsock_addr_init(&vchild->local_addr, le64_to_cpu(pkt->hdr.dst_cid),
<------><------><------>le32_to_cpu(pkt->hdr.dst_port));
<------>vsock_addr_init(&vchild->remote_addr, le64_to_cpu(pkt->hdr.src_cid),
<------><------><------>le32_to_cpu(pkt->hdr.src_port));
 
<------>ret = vsock_assign_transport(vchild, vsk);
<------>/* Transport assigned (looking at remote_addr) must be the same
<------> * where we received the request.
<------> */
<------>if (ret || vchild->transport != &t->transport) {
<------><------>release_sock(child);
<------><------>virtio_transport_reset_no_sock(t, pkt);
<------><------>sock_put(child);
<------><------>return ret;
<------>}
 
<------>if (virtio_transport_space_update(child, pkt))
<------><------>child->sk_write_space(child);
 
<------>vsock_insert_connected(vchild);
<------>vsock_enqueue_accept(sk, child);
<------>virtio_transport_send_response(vchild, pkt);
 
<------>release_sock(child);
 
<------>sk->sk_data_ready(sk);
<------>return 0;
}
 
/* We are under the virtio-vsock's vsock->rx_lock or vhost-vsock's vq->mutex
 * lock.
 */
void virtio_transport_recv_pkt(struct virtio_transport *t,
<------><------><------>       struct virtio_vsock_pkt *pkt)
{
<------>struct sockaddr_vm src, dst;
<------>struct vsock_sock *vsk;
<------>struct sock *sk;
<------>bool space_available;
 
<------>vsock_addr_init(&src, le64_to_cpu(pkt->hdr.src_cid),
<------><------><------>le32_to_cpu(pkt->hdr.src_port));
<------>vsock_addr_init(&dst, le64_to_cpu(pkt->hdr.dst_cid),
<------><------><------>le32_to_cpu(pkt->hdr.dst_port));
 
<------>trace_virtio_transport_recv_pkt(src.svm_cid, src.svm_port,
<------><------><------><------><------>dst.svm_cid, dst.svm_port,
<------><------><------><------><------>le32_to_cpu(pkt->hdr.len),
<------><------><------><------><------>le16_to_cpu(pkt->hdr.type),
<------><------><------><------><------>le16_to_cpu(pkt->hdr.op),
<------><------><------><------><------>le32_to_cpu(pkt->hdr.flags),
<------><------><------><------><------>le32_to_cpu(pkt->hdr.buf_alloc),
<------><------><------><------><------>le32_to_cpu(pkt->hdr.fwd_cnt));
 
<------>if (le16_to_cpu(pkt->hdr.type) != VIRTIO_VSOCK_TYPE_STREAM) {
<------><------>(void)virtio_transport_reset_no_sock(t, pkt);
<------><------>goto free_pkt;
<------>}
 
<------>/* 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) {
<------><------><------>(void)virtio_transport_reset_no_sock(t, pkt);
<------><------><------>goto free_pkt;
<------><------>}
<------>}
 
<------>vsk = vsock_sk(sk);
 
<------>lock_sock(sk);
 
<------>/* Check if sk has been closed before lock_sock */
<------>if (sock_flag(sk, SOCK_DONE)) {
<------><------>(void)virtio_transport_reset_no_sock(t, pkt);
<------><------>release_sock(sk);
<------><------>sock_put(sk);
<------><------>goto free_pkt;
<------>}
 
<------>space_available = virtio_transport_space_update(sk, pkt);
 
<------>/* Update CID in case it has changed after a transport reset event */
<------>if (vsk->local_addr.svm_cid != VMADDR_CID_ANY)
<------><------>vsk->local_addr.svm_cid = dst.svm_cid;
 
<------>if (space_available)
<------><------>sk->sk_write_space(sk);
 
<------>switch (sk->sk_state) {
<------>case TCP_LISTEN:
<------><------>virtio_transport_recv_listen(sk, pkt, t);
<------><------>virtio_transport_free_pkt(pkt);
<------><------>break;
<------>case TCP_SYN_SENT:
<------><------>virtio_transport_recv_connecting(sk, pkt);
<------><------>virtio_transport_free_pkt(pkt);
<------><------>break;
<------>case TCP_ESTABLISHED:
<------><------>virtio_transport_recv_connected(sk, pkt);
<------><------>break;
<------>case TCP_CLOSING:
<------><------>virtio_transport_recv_disconnecting(sk, pkt);
<------><------>virtio_transport_free_pkt(pkt);
<------><------>break;
<------>default:
<------><------>(void)virtio_transport_reset_no_sock(t, pkt);
<------><------>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);
 
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Asias He");
MODULE_DESCRIPTION("common code for virtio vsock");