um: Add legacy tap support and rename existing vector to hybrid

1. Adds legacy tap support
2. Renames tap+raw as hybrid

Signed-off-by: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

4 files changed, 151 insertions, 87 deletions

diff --git a/arch/um/drivers/vector_kern.c b/arch/um/drivers/vector_kern.c
index e190e4ca52e1..8fa094770965 100644
--- a/arch/um/drivers/vector_kern.c
+++ b/arch/um/drivers/vector_kern.c
@@ -186,6 +186,8 @@ static int get_transport_options(struct arglist *def)
 
 
         if (strncmp(transport, TRANS_TAP, TRANS_TAP_LEN) == 0)
+                return 0;
+        if (strncmp(transport, TRANS_HYBRID, TRANS_HYBRID_LEN) == 0)
                 return (vec_rx | VECTOR_BPF);
         if (strncmp(transport, TRANS_RAW, TRANS_RAW_LEN) == 0)
                 return (vec_rx | vec_tx | VECTOR_QDISC_BYPASS);
diff --git a/arch/um/drivers/vector_transports.c b/arch/um/drivers/vector_transports.c
index 77e4ebc206ae..2999f3bd1781 100644
--- a/arch/um/drivers/vector_transports.c
+++ b/arch/um/drivers/vector_transports.c
@@ -418,7 +418,7 @@ static int build_raw_transport_data(struct vector_private *vp)
         return 0;
 }
 
-static int build_tap_transport_data(struct vector_private *vp)
+static int build_hybrid_transport_data(struct vector_private *vp)
 {
         if (uml_raw_enable_vnet_headers(vp->fds->rx_fd)) {
                 vp->form_header = &raw_form_header;
@@ -432,7 +432,7 @@ static int build_tap_transport_data(struct vector_private *vp)
                                 NETIF_F_TSO | NETIF_F_GSO | NETIF_F_GRO);
                 netdev_info(
                         vp->dev,
-                        "tap/raw: using vnet headers for tso and tx/rx checksum"
+                        "tap/raw hybrid: using vnet headers for tso and tx/rx checksum"
                 );
         } else {
                 return 0; /* do not try to enable tap too if raw failed */
@@ -442,6 +442,29 @@ static int build_tap_transport_data(struct vector_private *vp)
         return -1;
 }
 
+static int build_tap_transport_data(struct vector_private *vp)
+{
+        /* "Pure" tap uses the same fd for rx and tx */
+        if (uml_tap_enable_vnet_headers(vp->fds->tx_fd)) {
+                vp->form_header = &raw_form_header;
+                vp->verify_header = &raw_verify_header;
+                vp->header_size = sizeof(struct virtio_net_hdr);
+                vp->rx_header_size = sizeof(struct virtio_net_hdr);
+                vp->dev->hw_features |=
+                        (NETIF_F_TSO | NETIF_F_GSO | NETIF_F_GRO);
+                vp->dev->features |=
+                        (NETIF_F_RXCSUM | NETIF_F_HW_CSUM |
+                                NETIF_F_TSO | NETIF_F_GSO | NETIF_F_GRO);
+                netdev_info(
+                        vp->dev,
+                        "tap: using vnet headers for tso and tx/rx checksum"
+                );
+                return 0;
+        }
+        return -1;
+}
+
+
 int build_transport_data(struct vector_private *vp)
 {
         char *transport = uml_vector_fetch_arg(vp->parsed, "transport");
@@ -454,6 +477,8 @@ int build_transport_data(struct vector_private *vp)
                 return build_raw_transport_data(vp);
         if (strncmp(transport, TRANS_TAP, TRANS_TAP_LEN) == 0)
                 return build_tap_transport_data(vp);
+        if (strncmp(transport, TRANS_HYBRID, TRANS_HYBRID_LEN) == 0)
+                return build_hybrid_transport_data(vp);
         return 0;
 }
 
diff --git a/arch/um/drivers/vector_user.c b/arch/um/drivers/vector_user.c
index b3f7b3ca896d..0ada22f82965 100644
--- a/arch/um/drivers/vector_user.c
+++ b/arch/um/drivers/vector_user.c
@@ -114,12 +114,76 @@ cleanup:
 
 #define PATH_NET_TUN "/dev/net/tun"
 
-static struct vector_fds *user_init_tap_fds(struct arglist *ifspec)
+
+static int create_tap_fd(char *iface)
 {
         struct ifreq ifr;
         int fd = -1;
-        struct sockaddr_ll sock;
         int err = -ENOMEM, offload;
+
+        fd = open(PATH_NET_TUN, O_RDWR);
+        if (fd < 0) {
+                printk(UM_KERN_ERR "uml_tap: failed to open tun device\n");
+                goto tap_fd_cleanup;
+        }
+        memset(&ifr, 0, sizeof(ifr));
+        ifr.ifr_flags = IFF_TAP | IFF_NO_PI | IFF_VNET_HDR;
+        strncpy((char *)&ifr.ifr_name, iface, sizeof(ifr.ifr_name) - 1);
+
+        err = ioctl(fd, TUNSETIFF, (void *) &ifr);
+        if (err != 0) {
+                printk(UM_KERN_ERR "uml_tap: failed to select tap interface\n");
+                goto tap_fd_cleanup;
+        }
+
+        offload = TUN_F_CSUM | TUN_F_TSO4 | TUN_F_TSO6;
+        ioctl(fd, TUNSETOFFLOAD, offload);
+        return fd;
+tap_fd_cleanup:
+        if (fd >= 0)
+                os_close_file(fd);
+        return err;
+}
+
+static int create_raw_fd(char *iface, int flags, int proto)
+{
+        struct ifreq ifr;
+        int fd = -1;
+        struct sockaddr_ll sock;
+        int err = -ENOMEM;
+
+        fd = socket(AF_PACKET, SOCK_RAW, flags);
+        if (fd == -1) {
+                err = -errno;
+                goto raw_fd_cleanup;
+        }
+        memset(&ifr, 0, sizeof(ifr));
+        strncpy((char *)&ifr.ifr_name, iface, sizeof(ifr.ifr_name) - 1);
+        if (ioctl(fd, SIOCGIFINDEX, (void *) &ifr) < 0) {
+                err = -errno;
+                goto raw_fd_cleanup;
+        }
+
+        sock.sll_family = AF_PACKET;
+        sock.sll_protocol = htons(proto);
+        sock.sll_ifindex = ifr.ifr_ifindex;
+
+        if (bind(fd,
+                (struct sockaddr *) &sock, sizeof(struct sockaddr_ll)) < 0) {
+                err = -errno;
+                goto raw_fd_cleanup;
+        }
+        return fd;
+raw_fd_cleanup:
+        printk(UM_KERN_ERR "user_init_raw: init failed, error %d", err);
+        if (fd >= 0)
+                os_close_file(fd);
+        return err;
+}
+
+static struct vector_fds *user_init_tap_fds(struct arglist *ifspec)
+{
+        int fd = -1;
         char *iface;
         struct vector_fds *result = NULL;
 
@@ -141,117 +205,88 @@ static struct vector_fds *user_init_tap_fds(struct arglist *ifspec)
 
         /* TAP */
 
-        fd = open(PATH_NET_TUN, O_RDWR);
+        fd = create_tap_fd(iface);
         if (fd < 0) {
-                printk(UM_KERN_ERR "uml_tap: failed to open tun device\n");
+                printk(UM_KERN_ERR "uml_tap: failed to create tun interface\n");
                 goto tap_cleanup;
         }
         result->tx_fd = fd;
-        memset(&ifr, 0, sizeof(ifr));
-        ifr.ifr_flags = IFF_TAP | IFF_NO_PI | IFF_VNET_HDR;
-        strncpy((char *)&ifr.ifr_name, iface, sizeof(ifr.ifr_name) - 1);
+        result->rx_fd = fd;
+        return result;
+tap_cleanup:
+        printk(UM_KERN_ERR "user_init_tap: init failed, error %d", fd);
+        if (result != NULL)
+                kfree(result);
+        return NULL;
+}
 
-        err = ioctl(fd, TUNSETIFF, (void *) &ifr);
-        if (err != 0) {
-                printk(UM_KERN_ERR "uml_tap: failed to select tap interface\n");
-                goto tap_cleanup;
+static struct vector_fds *user_init_hybrid_fds(struct arglist *ifspec)
+{
+        char *iface;
+        struct vector_fds *result = NULL;
+
+        iface = uml_vector_fetch_arg(ifspec, TOKEN_IFNAME);
+        if (iface == NULL) {
+                printk(UM_KERN_ERR "uml_tap: failed to parse interface spec\n");
+                goto hybrid_cleanup;
         }
 
-        offload = TUN_F_CSUM | TUN_F_TSO4 | TUN_F_TSO6;
-        ioctl(fd, TUNSETOFFLOAD, offload);
+        result = uml_kmalloc(sizeof(struct vector_fds), UM_GFP_KERNEL);
+        if (result == NULL) {
+                printk(UM_KERN_ERR "uml_tap: failed to allocate file descriptors\n");
+                goto hybrid_cleanup;
+        }
+        result->rx_fd = -1;
+        result->tx_fd = -1;
+        result->remote_addr = NULL;
+        result->remote_addr_size = 0;
 
-        /* RAW */
+        /* TAP */
 
-        fd = socket(AF_PACKET, SOCK_RAW, htons(ETH_P_ALL));
-        if (fd == -1) {
-                printk(UM_KERN_ERR
-                        "uml_tap: failed to create socket: %i\n", -errno);
-                goto tap_cleanup;
-        }
-        result->rx_fd = fd;
-        memset(&ifr, 0, sizeof(ifr));
-        strncpy((char *)&ifr.ifr_name, iface, sizeof(ifr.ifr_name) - 1);
-        if (ioctl(fd, SIOCGIFINDEX, (void *) &ifr) < 0) {
-                printk(UM_KERN_ERR
-                        "uml_tap: failed to set interface: %i\n", -errno);
-                goto tap_cleanup;
+        result->tx_fd = create_tap_fd(iface);
+        if (result->tx_fd < 0) {
+                printk(UM_KERN_ERR "uml_tap: failed to create tun interface: %i\n", result->tx_fd);
+                goto hybrid_cleanup;
         }
 
-        sock.sll_family = AF_PACKET;
-        sock.sll_protocol = htons(ETH_P_ALL);
-        sock.sll_ifindex = ifr.ifr_ifindex;
+        /* RAW */
 
-        if (bind(fd,
-                (struct sockaddr *) &sock, sizeof(struct sockaddr_ll)) < 0) {
+        result->rx_fd = create_raw_fd(iface, ETH_P_ALL, ETH_P_ALL);
+        if (result->rx_fd == -1) {
                 printk(UM_KERN_ERR
-                        "user_init_tap: failed to bind raw pair, err %d\n",
-                                -errno);
-                goto tap_cleanup;
+                        "uml_tap: failed to create paired raw socket: %i\n", result->rx_fd);
+                goto hybrid_cleanup;
         }
         return result;
-tap_cleanup:
-        printk(UM_KERN_ERR "user_init_tap: init failed, error %d", err);
-        if (result != NULL) {
-                if (result->rx_fd >= 0)
-                        os_close_file(result->rx_fd);
-                if (result->tx_fd >= 0)
-                        os_close_file(result->tx_fd);
+hybrid_cleanup:
+        printk(UM_KERN_ERR "user_init_hybrid: init failed");
+        if (result != NULL)
                 kfree(result);
-        }
         return NULL;
 }
 
 
 static struct vector_fds *user_init_raw_fds(struct arglist *ifspec)
 {
-        struct ifreq ifr;
         int rxfd = -1, txfd = -1;
-        struct sockaddr_ll sock;
         int err = -ENOMEM;
         char *iface;
         struct vector_fds *result = NULL;
 
         iface = uml_vector_fetch_arg(ifspec, TOKEN_IFNAME);
         if (iface == NULL)
-                goto cleanup;
+                goto raw_cleanup;
 
-        rxfd = socket(AF_PACKET, SOCK_RAW, ETH_P_ALL);
+        rxfd = create_raw_fd(iface, ETH_P_ALL, ETH_P_ALL);
         if (rxfd == -1) {
                 err = -errno;
-                goto cleanup;
+                goto raw_cleanup;
         }
-        txfd = socket(AF_PACKET, SOCK_RAW, 0); /* Turn off RX on this fd */
+        txfd = create_raw_fd(iface, 0, ETH_P_IP); /* Turn off RX on this fd */
         if (txfd == -1) {
                 err = -errno;
-                goto cleanup;
-        }
-        memset(&ifr, 0, sizeof(ifr));
-        strncpy((char *)&ifr.ifr_name, iface, sizeof(ifr.ifr_name) - 1);
-        if (ioctl(rxfd, SIOCGIFINDEX, (void *) &ifr) < 0) {
-                err = -errno;
-                goto cleanup;
-        }
-
-        sock.sll_family = AF_PACKET;
-        sock.sll_protocol = htons(ETH_P_ALL);
-        sock.sll_ifindex = ifr.ifr_ifindex;
-
-        if (bind(rxfd,
-                (struct sockaddr *) &sock, sizeof(struct sockaddr_ll)) < 0) {
-                err = -errno;
-                goto cleanup;
+                goto raw_cleanup;
         }
-
-        sock.sll_family = AF_PACKET;
-        sock.sll_protocol = htons(ETH_P_IP);
-        sock.sll_ifindex = ifr.ifr_ifindex;
-
-        if (bind(txfd,
-                (struct sockaddr *) &sock, sizeof(struct sockaddr_ll)) < 0) {
-                err = -errno;
-                goto cleanup;
-        }
-
         result = uml_kmalloc(sizeof(struct vector_fds), UM_GFP_KERNEL);
         if (result != NULL) {
                 result->rx_fd = rxfd;
@@ -260,13 +295,10 @@ static struct vector_fds *user_init_raw_fds(struct arglist *ifspec)
                 result->remote_addr_size = 0;
         }
         return result;
-cleanup:
+raw_cleanup:
         printk(UM_KERN_ERR "user_init_raw: init failed, error %d", err);
-        if (rxfd >= 0)
-                os_close_file(rxfd);
-        if (txfd >= 0)
-                os_close_file(txfd);
-        kfree(result);
+        if (result != NULL)
+                kfree(result);
         return NULL;
 }
 
@@ -456,6 +488,8 @@ struct vector_fds *uml_vector_user_open(
         }
         if (strncmp(transport, TRANS_RAW, TRANS_RAW_LEN) == 0)
                 return user_init_raw_fds(parsed);
+        if (strncmp(transport, TRANS_HYBRID, TRANS_HYBRID_LEN) == 0)
+                return user_init_hybrid_fds(parsed);
         if (strncmp(transport, TRANS_TAP, TRANS_TAP_LEN) == 0)
                 return user_init_tap_fds(parsed);
         if (strncmp(transport, TRANS_GRE, TRANS_GRE_LEN) == 0)
@@ -482,8 +516,9 @@ int uml_vector_sendmsg(int fd, void *hdr, int flags)
 int uml_vector_recvmsg(int fd, void *hdr, int flags)
 {
         int n;
+        struct msghdr *msg = (struct msghdr *) hdr;
 
-        CATCH_EINTR(n = recvmsg(fd, (struct msghdr *) hdr,  flags));
+        CATCH_EINTR(n = readv(fd, msg->msg_iov, msg->msg_iovlen));
         if ((n < 0) && (errno == EAGAIN))
                 return 0;
         if (n >= 0)
diff --git a/arch/um/drivers/vector_user.h b/arch/um/drivers/vector_user.h
index d7cbff73b7ff..6bf50cf78ad0 100644
--- a/arch/um/drivers/vector_user.h
+++ b/arch/um/drivers/vector_user.h
@@ -16,13 +16,15 @@
 #define TRANS_TAP "tap"
 #define TRANS_TAP_LEN strlen(TRANS_TAP)
 
-
 #define TRANS_GRE "gre"
 #define TRANS_GRE_LEN strlen(TRANS_RAW)
 
 #define TRANS_L2TPV3 "l2tpv3"
 #define TRANS_L2TPV3_LEN strlen(TRANS_L2TPV3)
 
+#define TRANS_HYBRID "hybrid"
+#define TRANS_HYBRID_LEN strlen(TRANS_HYBRID)
+
 #ifndef IPPROTO_GRE
 #define IPPROTO_GRE 0x2F
 #endif