Yuanhan Liu e623e0c6d8 vhost: add reconnect ability
Allow reconnecting on failure by default when:

- DPDK app starts first and QEMU (as the server) is not started yet.
  Without reconnecting, DPDK app would simply fail on vhost-user
  registration.

- QEMU restarts, say due to OS reboot.
  Without reconnecting, you can't re-establish the connection without
  restarting DPDK app.

This patch make it work well for both above cases. It simply creates
a new thread, and keep trying calling "connect()", until it succeeds.

The reconnect could be disabled when RTE_VHOST_USER_NO_RECONNECT flag
is set.

Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
2016-06-22 09:47:12 +02:00

684 lines
16 KiB
C

/*-
* BSD LICENSE
*
* Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Intel Corporation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <stdint.h>
#include <stdio.h>
#include <stdbool.h>
#include <limits.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <sys/queue.h>
#include <errno.h>
#include <pthread.h>
#include <rte_log.h>
#include <rte_virtio_net.h>
#include "fd_man.h"
#include "vhost-net-user.h"
#include "vhost-net.h"
#include "virtio-net-user.h"
/*
* Every time rte_vhost_driver_register() is invoked, an associated
* vhost_user_socket struct will be created.
*/
struct vhost_user_socket {
char *path;
int listenfd;
bool is_server;
bool reconnect;
};
struct vhost_user_connection {
struct vhost_user_socket *vsocket;
int vid;
};
#define MAX_VHOST_SOCKET 1024
struct vhost_user {
struct vhost_user_socket *vsockets[MAX_VHOST_SOCKET];
struct fdset fdset;
int vsocket_cnt;
pthread_mutex_t mutex;
};
#define MAX_VIRTIO_BACKLOG 128
static void vhost_user_server_new_connection(int fd, void *data, int *remove);
static void vhost_user_msg_handler(int fd, void *dat, int *remove);
static int vhost_user_create_client(struct vhost_user_socket *vsocket);
static struct vhost_user vhost_user = {
.fdset = {
.fd = { [0 ... MAX_FDS - 1] = {-1, NULL, NULL, NULL, 0} },
.fd_mutex = PTHREAD_MUTEX_INITIALIZER,
.num = 0
},
.vsocket_cnt = 0,
.mutex = PTHREAD_MUTEX_INITIALIZER,
};
static const char *vhost_message_str[VHOST_USER_MAX] = {
[VHOST_USER_NONE] = "VHOST_USER_NONE",
[VHOST_USER_GET_FEATURES] = "VHOST_USER_GET_FEATURES",
[VHOST_USER_SET_FEATURES] = "VHOST_USER_SET_FEATURES",
[VHOST_USER_SET_OWNER] = "VHOST_USER_SET_OWNER",
[VHOST_USER_RESET_OWNER] = "VHOST_USER_RESET_OWNER",
[VHOST_USER_SET_MEM_TABLE] = "VHOST_USER_SET_MEM_TABLE",
[VHOST_USER_SET_LOG_BASE] = "VHOST_USER_SET_LOG_BASE",
[VHOST_USER_SET_LOG_FD] = "VHOST_USER_SET_LOG_FD",
[VHOST_USER_SET_VRING_NUM] = "VHOST_USER_SET_VRING_NUM",
[VHOST_USER_SET_VRING_ADDR] = "VHOST_USER_SET_VRING_ADDR",
[VHOST_USER_SET_VRING_BASE] = "VHOST_USER_SET_VRING_BASE",
[VHOST_USER_GET_VRING_BASE] = "VHOST_USER_GET_VRING_BASE",
[VHOST_USER_SET_VRING_KICK] = "VHOST_USER_SET_VRING_KICK",
[VHOST_USER_SET_VRING_CALL] = "VHOST_USER_SET_VRING_CALL",
[VHOST_USER_SET_VRING_ERR] = "VHOST_USER_SET_VRING_ERR",
[VHOST_USER_GET_PROTOCOL_FEATURES] = "VHOST_USER_GET_PROTOCOL_FEATURES",
[VHOST_USER_SET_PROTOCOL_FEATURES] = "VHOST_USER_SET_PROTOCOL_FEATURES",
[VHOST_USER_GET_QUEUE_NUM] = "VHOST_USER_GET_QUEUE_NUM",
[VHOST_USER_SET_VRING_ENABLE] = "VHOST_USER_SET_VRING_ENABLE",
[VHOST_USER_SEND_RARP] = "VHOST_USER_SEND_RARP",
};
/* return bytes# of read on success or negative val on failure. */
static int
read_fd_message(int sockfd, char *buf, int buflen, int *fds, int fd_num)
{
struct iovec iov;
struct msghdr msgh;
size_t fdsize = fd_num * sizeof(int);
char control[CMSG_SPACE(fdsize)];
struct cmsghdr *cmsg;
int ret;
memset(&msgh, 0, sizeof(msgh));
iov.iov_base = buf;
iov.iov_len = buflen;
msgh.msg_iov = &iov;
msgh.msg_iovlen = 1;
msgh.msg_control = control;
msgh.msg_controllen = sizeof(control);
ret = recvmsg(sockfd, &msgh, 0);
if (ret <= 0) {
RTE_LOG(ERR, VHOST_CONFIG, "recvmsg failed\n");
return ret;
}
if (msgh.msg_flags & (MSG_TRUNC | MSG_CTRUNC)) {
RTE_LOG(ERR, VHOST_CONFIG, "truncted msg\n");
return -1;
}
for (cmsg = CMSG_FIRSTHDR(&msgh); cmsg != NULL;
cmsg = CMSG_NXTHDR(&msgh, cmsg)) {
if ((cmsg->cmsg_level == SOL_SOCKET) &&
(cmsg->cmsg_type == SCM_RIGHTS)) {
memcpy(fds, CMSG_DATA(cmsg), fdsize);
break;
}
}
return ret;
}
/* return bytes# of read on success or negative val on failure. */
static int
read_vhost_message(int sockfd, struct VhostUserMsg *msg)
{
int ret;
ret = read_fd_message(sockfd, (char *)msg, VHOST_USER_HDR_SIZE,
msg->fds, VHOST_MEMORY_MAX_NREGIONS);
if (ret <= 0)
return ret;
if (msg && msg->size) {
if (msg->size > sizeof(msg->payload)) {
RTE_LOG(ERR, VHOST_CONFIG,
"invalid msg size: %d\n", msg->size);
return -1;
}
ret = read(sockfd, &msg->payload, msg->size);
if (ret <= 0)
return ret;
if (ret != (int)msg->size) {
RTE_LOG(ERR, VHOST_CONFIG,
"read control message failed\n");
return -1;
}
}
return ret;
}
static int
send_fd_message(int sockfd, char *buf, int buflen, int *fds, int fd_num)
{
struct iovec iov;
struct msghdr msgh;
size_t fdsize = fd_num * sizeof(int);
char control[CMSG_SPACE(fdsize)];
struct cmsghdr *cmsg;
int ret;
memset(&msgh, 0, sizeof(msgh));
iov.iov_base = buf;
iov.iov_len = buflen;
msgh.msg_iov = &iov;
msgh.msg_iovlen = 1;
if (fds && fd_num > 0) {
msgh.msg_control = control;
msgh.msg_controllen = sizeof(control);
cmsg = CMSG_FIRSTHDR(&msgh);
cmsg->cmsg_len = CMSG_LEN(fdsize);
cmsg->cmsg_level = SOL_SOCKET;
cmsg->cmsg_type = SCM_RIGHTS;
memcpy(CMSG_DATA(cmsg), fds, fdsize);
} else {
msgh.msg_control = NULL;
msgh.msg_controllen = 0;
}
do {
ret = sendmsg(sockfd, &msgh, 0);
} while (ret < 0 && errno == EINTR);
if (ret < 0) {
RTE_LOG(ERR, VHOST_CONFIG, "sendmsg error\n");
return ret;
}
return ret;
}
static int
send_vhost_message(int sockfd, struct VhostUserMsg *msg)
{
int ret;
if (!msg)
return 0;
msg->flags &= ~VHOST_USER_VERSION_MASK;
msg->flags |= VHOST_USER_VERSION;
msg->flags |= VHOST_USER_REPLY_MASK;
ret = send_fd_message(sockfd, (char *)msg,
VHOST_USER_HDR_SIZE + msg->size, NULL, 0);
return ret;
}
static void
vhost_user_add_connection(int fd, struct vhost_user_socket *vsocket)
{
int vid;
size_t size;
struct vhost_user_connection *conn;
conn = malloc(sizeof(*conn));
if (conn == NULL) {
close(fd);
return;
}
vid = vhost_new_device();
if (vid == -1) {
close(fd);
free(conn);
return;
}
size = strnlen(vsocket->path, PATH_MAX);
vhost_set_ifname(vid, vsocket->path, size);
RTE_LOG(INFO, VHOST_CONFIG, "new device, handle is %d\n", vid);
conn->vsocket = vsocket;
conn->vid = vid;
fdset_add(&vhost_user.fdset, fd, vhost_user_msg_handler, NULL, conn);
}
/* call back when there is new vhost-user connection from client */
static void
vhost_user_server_new_connection(int fd, void *dat, int *remove __rte_unused)
{
struct vhost_user_socket *vsocket = dat;
fd = accept(fd, NULL, NULL);
if (fd < 0)
return;
RTE_LOG(INFO, VHOST_CONFIG, "new vhost user connection is %d\n", fd);
vhost_user_add_connection(fd, vsocket);
}
/* callback when there is message on the connfd */
static void
vhost_user_msg_handler(int connfd, void *dat, int *remove)
{
int vid;
struct vhost_user_connection *conn = dat;
struct VhostUserMsg msg;
uint64_t features;
int ret;
vid = conn->vid;
ret = read_vhost_message(connfd, &msg);
if (ret <= 0 || msg.request >= VHOST_USER_MAX) {
struct vhost_user_socket *vsocket = conn->vsocket;
if (ret < 0)
RTE_LOG(ERR, VHOST_CONFIG,
"vhost read message failed\n");
else if (ret == 0)
RTE_LOG(INFO, VHOST_CONFIG,
"vhost peer closed\n");
else
RTE_LOG(ERR, VHOST_CONFIG,
"vhost read incorrect message\n");
close(connfd);
*remove = 1;
free(conn);
vhost_destroy_device(vid);
if (vsocket->reconnect)
vhost_user_create_client(vsocket);
return;
}
RTE_LOG(INFO, VHOST_CONFIG, "read message %s\n",
vhost_message_str[msg.request]);
switch (msg.request) {
case VHOST_USER_GET_FEATURES:
ret = vhost_get_features(vid, &features);
msg.payload.u64 = features;
msg.size = sizeof(msg.payload.u64);
send_vhost_message(connfd, &msg);
break;
case VHOST_USER_SET_FEATURES:
features = msg.payload.u64;
vhost_set_features(vid, &features);
break;
case VHOST_USER_GET_PROTOCOL_FEATURES:
msg.payload.u64 = VHOST_USER_PROTOCOL_FEATURES;
msg.size = sizeof(msg.payload.u64);
send_vhost_message(connfd, &msg);
break;
case VHOST_USER_SET_PROTOCOL_FEATURES:
user_set_protocol_features(vid, msg.payload.u64);
break;
case VHOST_USER_SET_OWNER:
vhost_set_owner(vid);
break;
case VHOST_USER_RESET_OWNER:
vhost_reset_owner(vid);
break;
case VHOST_USER_SET_MEM_TABLE:
user_set_mem_table(vid, &msg);
break;
case VHOST_USER_SET_LOG_BASE:
user_set_log_base(vid, &msg);
/* it needs a reply */
msg.size = sizeof(msg.payload.u64);
send_vhost_message(connfd, &msg);
break;
case VHOST_USER_SET_LOG_FD:
close(msg.fds[0]);
RTE_LOG(INFO, VHOST_CONFIG, "not implemented.\n");
break;
case VHOST_USER_SET_VRING_NUM:
vhost_set_vring_num(vid, &msg.payload.state);
break;
case VHOST_USER_SET_VRING_ADDR:
vhost_set_vring_addr(vid, &msg.payload.addr);
break;
case VHOST_USER_SET_VRING_BASE:
vhost_set_vring_base(vid, &msg.payload.state);
break;
case VHOST_USER_GET_VRING_BASE:
ret = user_get_vring_base(vid, &msg.payload.state);
msg.size = sizeof(msg.payload.state);
send_vhost_message(connfd, &msg);
break;
case VHOST_USER_SET_VRING_KICK:
user_set_vring_kick(vid, &msg);
break;
case VHOST_USER_SET_VRING_CALL:
user_set_vring_call(vid, &msg);
break;
case VHOST_USER_SET_VRING_ERR:
if (!(msg.payload.u64 & VHOST_USER_VRING_NOFD_MASK))
close(msg.fds[0]);
RTE_LOG(INFO, VHOST_CONFIG, "not implemented\n");
break;
case VHOST_USER_GET_QUEUE_NUM:
msg.payload.u64 = VHOST_MAX_QUEUE_PAIRS;
msg.size = sizeof(msg.payload.u64);
send_vhost_message(connfd, &msg);
break;
case VHOST_USER_SET_VRING_ENABLE:
user_set_vring_enable(vid, &msg.payload.state);
break;
case VHOST_USER_SEND_RARP:
user_send_rarp(vid, &msg);
break;
default:
break;
}
}
static int
create_unix_socket(const char *path, struct sockaddr_un *un, bool is_server)
{
int fd;
fd = socket(AF_UNIX, SOCK_STREAM, 0);
if (fd < 0)
return -1;
RTE_LOG(INFO, VHOST_CONFIG, "vhost-user %s: socket created, fd: %d\n",
is_server ? "server" : "client", fd);
memset(un, 0, sizeof(*un));
un->sun_family = AF_UNIX;
strncpy(un->sun_path, path, sizeof(un->sun_path));
return fd;
}
static int
vhost_user_create_server(struct vhost_user_socket *vsocket)
{
int fd;
int ret;
struct sockaddr_un un;
const char *path = vsocket->path;
fd = create_unix_socket(path, &un, vsocket->is_server);
if (fd < 0)
return -1;
ret = bind(fd, (struct sockaddr *)&un, sizeof(un));
if (ret < 0) {
RTE_LOG(ERR, VHOST_CONFIG,
"failed to bind to %s: %s; remove it and try again\n",
path, strerror(errno));
goto err;
}
RTE_LOG(INFO, VHOST_CONFIG, "bind to %s\n", path);
ret = listen(fd, MAX_VIRTIO_BACKLOG);
if (ret < 0)
goto err;
vsocket->listenfd = fd;
fdset_add(&vhost_user.fdset, fd, vhost_user_server_new_connection,
NULL, vsocket);
return 0;
err:
close(fd);
return -1;
}
struct vhost_user_reconnect {
struct sockaddr_un un;
int fd;
struct vhost_user_socket *vsocket;
TAILQ_ENTRY(vhost_user_reconnect) next;
};
TAILQ_HEAD(vhost_user_reconnect_tailq_list, vhost_user_reconnect);
struct vhost_user_reconnect_list {
struct vhost_user_reconnect_tailq_list head;
pthread_mutex_t mutex;
};
static struct vhost_user_reconnect_list reconn_list;
static pthread_t reconn_tid;
static void *
vhost_user_client_reconnect(void *arg __rte_unused)
{
struct vhost_user_reconnect *reconn, *next;
while (1) {
pthread_mutex_lock(&reconn_list.mutex);
/*
* An equal implementation of TAILQ_FOREACH_SAFE,
* which does not exist on all platforms.
*/
for (reconn = TAILQ_FIRST(&reconn_list.head);
reconn != NULL; reconn = next) {
next = TAILQ_NEXT(reconn, next);
if (connect(reconn->fd, (struct sockaddr *)&reconn->un,
sizeof(reconn->un)) < 0)
continue;
RTE_LOG(INFO, VHOST_CONFIG,
"%s: connected\n", reconn->vsocket->path);
vhost_user_add_connection(reconn->fd, reconn->vsocket);
TAILQ_REMOVE(&reconn_list.head, reconn, next);
free(reconn);
}
pthread_mutex_unlock(&reconn_list.mutex);
sleep(1);
}
return NULL;
}
static int
vhost_user_reconnect_init(void)
{
int ret;
pthread_mutex_init(&reconn_list.mutex, NULL);
TAILQ_INIT(&reconn_list.head);
ret = pthread_create(&reconn_tid, NULL,
vhost_user_client_reconnect, NULL);
if (ret < 0)
RTE_LOG(ERR, VHOST_CONFIG, "failed to create reconnect thread");
return ret;
}
static int
vhost_user_create_client(struct vhost_user_socket *vsocket)
{
int fd;
int ret;
struct sockaddr_un un;
const char *path = vsocket->path;
struct vhost_user_reconnect *reconn;
fd = create_unix_socket(path, &un, vsocket->is_server);
if (fd < 0)
return -1;
ret = connect(fd, (struct sockaddr *)&un, sizeof(un));
if (ret == 0) {
vhost_user_add_connection(fd, vsocket);
return 0;
}
RTE_LOG(ERR, VHOST_CONFIG,
"failed to connect to %s: %s\n",
path, strerror(errno));
if (!vsocket->reconnect) {
close(fd);
return -1;
}
RTE_LOG(ERR, VHOST_CONFIG, "%s: reconnecting...\n", path);
reconn = malloc(sizeof(*reconn));
reconn->un = un;
reconn->fd = fd;
reconn->vsocket = vsocket;
pthread_mutex_lock(&reconn_list.mutex);
TAILQ_INSERT_TAIL(&reconn_list.head, reconn, next);
pthread_mutex_unlock(&reconn_list.mutex);
return 0;
}
/*
* Register a new vhost-user socket; here we could act as server
* (the default case), or client (when RTE_VHOST_USER_CLIENT) flag
* is set.
*/
int
rte_vhost_driver_register(const char *path, uint64_t flags)
{
int ret = -1;
struct vhost_user_socket *vsocket;
if (!path)
return -1;
pthread_mutex_lock(&vhost_user.mutex);
if (vhost_user.vsocket_cnt == MAX_VHOST_SOCKET) {
RTE_LOG(ERR, VHOST_CONFIG,
"error: the number of vhost sockets reaches maximum\n");
goto out;
}
vsocket = malloc(sizeof(struct vhost_user_socket));
if (!vsocket)
goto out;
memset(vsocket, 0, sizeof(struct vhost_user_socket));
vsocket->path = strdup(path);
if ((flags & RTE_VHOST_USER_CLIENT) != 0) {
vsocket->reconnect = !(flags & RTE_VHOST_USER_NO_RECONNECT);
if (vsocket->reconnect && reconn_tid == 0) {
if (vhost_user_reconnect_init() < 0)
goto out;
}
ret = vhost_user_create_client(vsocket);
} else {
vsocket->is_server = true;
ret = vhost_user_create_server(vsocket);
}
if (ret < 0) {
free(vsocket->path);
free(vsocket);
goto out;
}
vhost_user.vsockets[vhost_user.vsocket_cnt++] = vsocket;
out:
pthread_mutex_unlock(&vhost_user.mutex);
return ret;
}
/**
* Unregister the specified vhost socket
*/
int
rte_vhost_driver_unregister(const char *path)
{
int i;
int count;
pthread_mutex_lock(&vhost_user.mutex);
for (i = 0; i < vhost_user.vsocket_cnt; i++) {
if (!strcmp(vhost_user.vsockets[i]->path, path)) {
if (vhost_user.vsockets[i]->is_server) {
fdset_del(&vhost_user.fdset,
vhost_user.vsockets[i]->listenfd);
close(vhost_user.vsockets[i]->listenfd);
unlink(path);
}
free(vhost_user.vsockets[i]->path);
free(vhost_user.vsockets[i]);
count = --vhost_user.vsocket_cnt;
vhost_user.vsockets[i] = vhost_user.vsockets[count];
vhost_user.vsockets[count] = NULL;
pthread_mutex_unlock(&vhost_user.mutex);
return 0;
}
}
pthread_mutex_unlock(&vhost_user.mutex);
return -1;
}
int
rte_vhost_driver_session_start(void)
{
fdset_event_dispatch(&vhost_user.fdset);
return 0;
}