Implement communication protocol with proxy module by using netlink, and do some init work.
Signed-off-by: zhanghailiang <zhang.zhanghaili...@huawei.com> Signed-off-by: Gao feng <gaof...@cn.fujitsu.com> --- net/colo-nic.c | 171 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 171 insertions(+) diff --git a/net/colo-nic.c b/net/colo-nic.c index a4719ce..38d9bf5 100644 --- a/net/colo-nic.c +++ b/net/colo-nic.c @@ -15,7 +15,19 @@ #include "net/net.h" #include "net/colo-nic.h" #include "qemu/error-report.h" +#include <sys/ioctl.h> +#include <sys/socket.h> +#include <linux/netlink.h> +#define NETLINK_COLO 28 + +enum colo_netlink_op { + COLO_QUERY_CHECKPOINT = (NLMSG_MIN_TYPE + 1), + COLO_CHECKPOINT, + COLO_FAILOVER, + COLO_PROXY_INIT, + COLO_PROXY_RESET, /* UNUSED, will be used for continuous FT */ +}; typedef struct nic_device { NetClientState *nc; @@ -177,6 +189,12 @@ void colo_remove_nic_devices(NetClientState *nc) return; } + /* close netlink socket before cleanup tap device. */ + if (cp_info.sockfd >= 0) { + close(cp_info.sockfd); + cp_info.sockfd = -1; + } + QTAILQ_FOREACH_SAFE(nic, &nic_devices, next, next_nic) { if (nic->nc == nc) { configure_one_nic(nc, 0, colo_nic_side, cp_info.index); @@ -187,20 +205,173 @@ void colo_remove_nic_devices(NetClientState *nc) colo_nic_side = -1; } +static int colo_proxy_send(uint8_t *buff, uint64_t size, int type) +{ + struct sockaddr_nl sa; + struct nlmsghdr msg; + struct iovec iov; + struct msghdr mh; + int ret; + + memset(&sa, 0, sizeof(sa)); + sa.nl_family = AF_NETLINK; + sa.nl_pid = 0; + sa.nl_groups = 0; + + msg.nlmsg_len = NLMSG_SPACE(0); + msg.nlmsg_flags = NLM_F_REQUEST; + if (type == COLO_PROXY_INIT) { + msg.nlmsg_flags |= NLM_F_ACK; + } + msg.nlmsg_seq = 0; + /* This is untrusty */ + msg.nlmsg_pid = cp_info.index; + msg.nlmsg_type = type; + + iov.iov_base = &msg; + iov.iov_len = msg.nlmsg_len; + + mh.msg_name = &sa; + mh.msg_namelen = sizeof(sa); + mh.msg_iov = &iov; + mh.msg_iovlen = 1; + mh.msg_control = NULL; + mh.msg_controllen = 0; + mh.msg_flags = 0; + + ret = sendmsg(cp_info.sockfd, &mh, 0); + if (ret <= 0) { + error_report("can't send msg to kernel by netlink: %s", + strerror(errno)); + } + + return ret; +} + +/* error: return -1, otherwise return 0 */ +static int64_t colo_proxy_recv(uint8_t **buff, int flags) +{ + struct sockaddr_nl sa; + struct iovec iov; + struct msghdr mh = { + .msg_name = &sa, + .msg_namelen = sizeof(sa), + .msg_iov = &iov, + .msg_iovlen = 1, + }; + uint8_t *tmp = g_malloc(16384); + uint32_t size = 16384; + int64_t len = 0; + int ret; + + iov.iov_base = tmp; + iov.iov_len = size; +next: + ret = recvmsg(cp_info.sockfd, &mh, flags); + if (ret <= 0) { + goto out; + } + + len += ret; + if (mh.msg_flags & MSG_TRUNC) { + size += 16384; + tmp = g_realloc(tmp, size); + iov.iov_base = tmp + len; + iov.iov_len = size - len; + goto next; + } + + *buff = tmp; + return len; + +out: + g_free(tmp); + *buff = NULL; + return ret; +} + int colo_proxy_init(int side) { + int skfd = 0; + struct sockaddr_nl sa; + struct nlmsghdr *h; + struct timeval tv = {0, 500000}; /* timeout for recvmsg from kernel */ + int i = 1; int ret = -1; + uint8_t *buff = NULL; + int64_t size; + + skfd = socket(PF_NETLINK, SOCK_RAW, NETLINK_COLO); + if (skfd < 0) { + error_report("can not create a netlink socket: %s", strerror(errno)); + goto out; + } + cp_info.sockfd = skfd; + memset(&sa, 0, sizeof(sa)); + sa.nl_family = AF_NETLINK; + sa.nl_groups = 0; +retry: + sa.nl_pid = i++; + + if (i > 10) { + error_report("netlink bind error"); + goto out; + } + + ret = bind(skfd, (struct sockaddr *)&sa, sizeof(sa)); + if (ret < 0 && errno == EADDRINUSE) { + error_report("colo index %d has already in used", sa.nl_pid); + goto retry; + } + + cp_info.index = sa.nl_pid; + ret = colo_proxy_send(NULL, 0, COLO_PROXY_INIT); + if (ret < 0) { + goto out; + } + setsockopt(cp_info.sockfd, SOL_SOCKET, SO_RCVTIMEO, &tv, sizeof(tv)); + ret = -1; + size = colo_proxy_recv(&buff, 0); + /* disable SO_RCVTIMEO */ + tv.tv_usec = 0; + setsockopt(cp_info.sockfd, SOL_SOCKET, SO_RCVTIMEO, &tv, sizeof(tv)); + if (size < 0) { + error_report("Can't recv msg from kernel by netlink: %s", + strerror(errno)); + goto out; + } + + if (size) { + h = (struct nlmsghdr *)buff; + + if (h->nlmsg_type == NLMSG_ERROR) { + struct nlmsgerr *err = (struct nlmsgerr *)NLMSG_DATA(h); + if (size - sizeof(*h) < sizeof(*err)) { + goto out; + } + ret = -err->error; + if (ret) { + goto out; + } + } + } ret = configure_nic(side, cp_info.index); if (ret != 0) { error_report("excute colo-proxy-script failed"); } colo_nic_side = side; + +out: + g_free(buff); return ret; } void colo_proxy_destroy(int side) { + if (cp_info.sockfd >= 0) { + close(cp_info.sockfd); + } teardown_nic(side, cp_info.index); cp_info.index = -1; colo_nic_side = -1; -- 1.7.12.4