1 /* SPDX-License-Identifier: BSD-3-Clause 2 * Copyright(c) 2016 Intel Corporation 3 */ 4 5 #include <unistd.h> 6 #include <sys/types.h> 7 #include <sys/stat.h> 8 #include <fcntl.h> 9 #include <net/if.h> 10 #include <net/if_arp.h> 11 #include <errno.h> 12 #include <string.h> 13 #include <limits.h> 14 15 #include <rte_ether.h> 16 17 #include "vhost_kernel_tap.h" 18 #include "../virtio_logs.h" 19 #include "../virtio_pci.h" 20 21 int 22 vhost_kernel_tap_set_offload(int fd, uint64_t features) 23 { 24 unsigned int offload = 0; 25 26 if (features & (1ULL << VIRTIO_NET_F_GUEST_CSUM)) { 27 offload |= TUN_F_CSUM; 28 if (features & (1ULL << VIRTIO_NET_F_GUEST_TSO4)) 29 offload |= TUN_F_TSO4; 30 if (features & (1ULL << VIRTIO_NET_F_GUEST_TSO6)) 31 offload |= TUN_F_TSO6; 32 if (features & ((1ULL << VIRTIO_NET_F_GUEST_TSO4) | 33 (1ULL << VIRTIO_NET_F_GUEST_TSO6)) && 34 (features & (1ULL << VIRTIO_NET_F_GUEST_ECN))) 35 offload |= TUN_F_TSO_ECN; 36 if (features & (1ULL << VIRTIO_NET_F_GUEST_UFO)) 37 offload |= TUN_F_UFO; 38 } 39 40 /* Check if our kernel supports TUNSETOFFLOAD */ 41 if (ioctl(fd, TUNSETOFFLOAD, 0) != 0 && errno == EINVAL) { 42 PMD_DRV_LOG(ERR, "Kernel does't support TUNSETOFFLOAD\n"); 43 return -ENOTSUP; 44 } 45 46 if (ioctl(fd, TUNSETOFFLOAD, offload) != 0) { 47 offload &= ~TUN_F_UFO; 48 if (ioctl(fd, TUNSETOFFLOAD, offload) != 0) { 49 PMD_DRV_LOG(ERR, "TUNSETOFFLOAD ioctl() failed: %s\n", 50 strerror(errno)); 51 return -1; 52 } 53 } 54 55 return 0; 56 } 57 58 int 59 vhost_kernel_tap_set_queue(int fd, bool attach) 60 { 61 struct ifreq ifr = { 62 .ifr_flags = attach ? IFF_ATTACH_QUEUE : IFF_DETACH_QUEUE, 63 }; 64 65 return ioctl(fd, TUNSETQUEUE, &ifr); 66 } 67 68 int 69 vhost_kernel_open_tap(char **p_ifname, int hdr_size, int req_mq, 70 const char *mac, uint64_t features) 71 { 72 unsigned int tap_features; 73 char *tap_name = NULL; 74 int sndbuf = INT_MAX; 75 struct ifreq ifr; 76 int tapfd; 77 int ret; 78 79 /* TODO: 80 * 1. verify we can get/set vnet_hdr_len, tap_probe_vnet_hdr_len 81 * 2. get number of memory regions from vhost module parameter 82 * max_mem_regions, supported in newer version linux kernel 83 */ 84 tapfd = open(PATH_NET_TUN, O_RDWR); 85 if (tapfd < 0) { 86 PMD_DRV_LOG(ERR, "fail to open %s: %s", 87 PATH_NET_TUN, strerror(errno)); 88 return -1; 89 } 90 91 /* Construct ifr */ 92 memset(&ifr, 0, sizeof(ifr)); 93 ifr.ifr_flags = IFF_TAP | IFF_NO_PI; 94 95 if (ioctl(tapfd, TUNGETFEATURES, &tap_features) == -1) { 96 PMD_DRV_LOG(ERR, "TUNGETFEATURES failed: %s", strerror(errno)); 97 goto error; 98 } 99 if (tap_features & IFF_ONE_QUEUE) 100 ifr.ifr_flags |= IFF_ONE_QUEUE; 101 102 /* Let tap instead of vhost-net handle vnet header, as the latter does 103 * not support offloading. And in this case, we should not set feature 104 * bit VHOST_NET_F_VIRTIO_NET_HDR. 105 */ 106 if (tap_features & IFF_VNET_HDR) { 107 ifr.ifr_flags |= IFF_VNET_HDR; 108 } else { 109 PMD_DRV_LOG(ERR, "TAP does not support IFF_VNET_HDR"); 110 goto error; 111 } 112 113 if (req_mq) 114 ifr.ifr_flags |= IFF_MULTI_QUEUE; 115 116 if (*p_ifname) 117 strncpy(ifr.ifr_name, *p_ifname, IFNAMSIZ - 1); 118 else 119 strncpy(ifr.ifr_name, "tap%d", IFNAMSIZ - 1); 120 if (ioctl(tapfd, TUNSETIFF, (void *)&ifr) == -1) { 121 PMD_DRV_LOG(ERR, "TUNSETIFF failed: %s", strerror(errno)); 122 goto error; 123 } 124 125 tap_name = strdup(ifr.ifr_name); 126 if (!tap_name) { 127 PMD_DRV_LOG(ERR, "strdup ifname failed: %s", strerror(errno)); 128 goto error; 129 } 130 131 if (fcntl(tapfd, F_SETFL, O_NONBLOCK) < 0) { 132 PMD_DRV_LOG(ERR, "fcntl tapfd failed: %s", strerror(errno)); 133 goto error; 134 } 135 136 if (ioctl(tapfd, TUNSETVNETHDRSZ, &hdr_size) < 0) { 137 PMD_DRV_LOG(ERR, "TUNSETVNETHDRSZ failed: %s", strerror(errno)); 138 goto error; 139 } 140 141 if (ioctl(tapfd, TUNSETSNDBUF, &sndbuf) < 0) { 142 PMD_DRV_LOG(ERR, "TUNSETSNDBUF failed: %s", strerror(errno)); 143 goto error; 144 } 145 146 ret = vhost_kernel_tap_set_offload(tapfd, features); 147 if (ret < 0 && ret != -ENOTSUP) 148 goto error; 149 150 memset(&ifr, 0, sizeof(ifr)); 151 ifr.ifr_hwaddr.sa_family = ARPHRD_ETHER; 152 memcpy(ifr.ifr_hwaddr.sa_data, mac, RTE_ETHER_ADDR_LEN); 153 if (ioctl(tapfd, SIOCSIFHWADDR, (void *)&ifr) == -1) { 154 PMD_DRV_LOG(ERR, "SIOCSIFHWADDR failed: %s", strerror(errno)); 155 goto error; 156 } 157 158 free(*p_ifname); 159 *p_ifname = tap_name; 160 161 return tapfd; 162 error: 163 free(tap_name); 164 close(tapfd); 165 return -1; 166 } 167