Mark McLoughlin | c28b1c1 | 2009-10-22 17:49:12 +0100 | [diff] [blame] | 1 | /* |
| 2 | * QEMU System Emulator |
| 3 | * |
| 4 | * Copyright (c) 2003-2008 Fabrice Bellard |
| 5 | * Copyright (c) 2009 Red Hat, Inc. |
| 6 | * |
| 7 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
| 8 | * of this software and associated documentation files (the "Software"), to deal |
| 9 | * in the Software without restriction, including without limitation the rights |
| 10 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| 11 | * copies of the Software, and to permit persons to whom the Software is |
| 12 | * furnished to do so, subject to the following conditions: |
| 13 | * |
| 14 | * The above copyright notice and this permission notice shall be included in |
| 15 | * all copies or substantial portions of the Software. |
| 16 | * |
| 17 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| 18 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 19 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| 20 | * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| 21 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| 22 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
| 23 | * THE SOFTWARE. |
| 24 | */ |
| 25 | |
Peter Maydell | 2744d92 | 2016-01-29 17:50:00 +0000 | [diff] [blame] | 26 | #include "qemu/osdep.h" |
Paolo Bonzini | 1422e32 | 2012-10-24 08:43:34 +0200 | [diff] [blame] | 27 | #include "tap_int.h" |
| 28 | #include "tap-linux.h" |
Mark McLoughlin | c28b1c1 | 2009-10-22 17:49:12 +0100 | [diff] [blame] | 29 | #include "net/tap.h" |
Mark McLoughlin | c28b1c1 | 2009-10-22 17:49:12 +0100 | [diff] [blame] | 30 | |
| 31 | #include <net/if.h> |
| 32 | #include <sys/ioctl.h> |
| 33 | |
Paolo Bonzini | 9c17d61 | 2012-12-17 18:20:04 +0100 | [diff] [blame] | 34 | #include "sysemu/sysemu.h" |
Markus Armbruster | da34e65 | 2016-03-14 09:01:28 +0100 | [diff] [blame] | 35 | #include "qapi/error.h" |
Paolo Bonzini | 1de7afc | 2012-12-17 18:20:00 +0100 | [diff] [blame] | 36 | #include "qemu/error-report.h" |
Veronia Bahaa | f348b6d | 2016-03-20 19:16:19 +0200 | [diff] [blame] | 37 | #include "qemu/cutils.h" |
Mark McLoughlin | c28b1c1 | 2009-10-22 17:49:12 +0100 | [diff] [blame] | 38 | |
Michael Tokarev | 91ca60e | 2010-06-02 14:33:01 -0300 | [diff] [blame] | 39 | #define PATH_NET_TUN "/dev/net/tun" |
| 40 | |
Jason Wang | 264986e | 2013-01-30 19:12:34 +0800 | [diff] [blame] | 41 | int tap_open(char *ifname, int ifname_size, int *vnet_hdr, |
Markus Armbruster | 468dd82 | 2015-05-15 13:58:58 +0200 | [diff] [blame] | 42 | int vnet_hdr_required, int mq_required, Error **errp) |
Mark McLoughlin | c28b1c1 | 2009-10-22 17:49:12 +0100 | [diff] [blame] | 43 | { |
| 44 | struct ifreq ifr; |
| 45 | int fd, ret; |
Michael S. Tsirkin | 89e6d68 | 2012-11-12 09:13:04 +0200 | [diff] [blame] | 46 | int len = sizeof(struct virtio_net_hdr); |
Peter Lieven | d26e445 | 2013-02-25 10:17:08 +0100 | [diff] [blame] | 47 | unsigned int features; |
Mark McLoughlin | c28b1c1 | 2009-10-22 17:49:12 +0100 | [diff] [blame] | 48 | |
Michael Tokarev | 91ca60e | 2010-06-02 14:33:01 -0300 | [diff] [blame] | 49 | TFR(fd = open(PATH_NET_TUN, O_RDWR)); |
Mark McLoughlin | c28b1c1 | 2009-10-22 17:49:12 +0100 | [diff] [blame] | 50 | if (fd < 0) { |
Markus Armbruster | 47896e2 | 2015-05-15 13:58:59 +0200 | [diff] [blame] | 51 | error_setg_errno(errp, errno, "could not open %s", PATH_NET_TUN); |
Mark McLoughlin | c28b1c1 | 2009-10-22 17:49:12 +0100 | [diff] [blame] | 52 | return -1; |
| 53 | } |
| 54 | memset(&ifr, 0, sizeof(ifr)); |
| 55 | ifr.ifr_flags = IFF_TAP | IFF_NO_PI; |
| 56 | |
Kusanagi Kouichi | 1f149e7 | 2014-01-18 14:38:45 +0900 | [diff] [blame] | 57 | if (ioctl(fd, TUNGETFEATURES, &features) == -1) { |
Alistair Francis | 3dc6f86 | 2017-07-12 06:57:41 -0700 | [diff] [blame] | 58 | warn_report("TUNGETFEATURES failed: %s", strerror(errno)); |
Kusanagi Kouichi | 1f149e7 | 2014-01-18 14:38:45 +0900 | [diff] [blame] | 59 | features = 0; |
| 60 | } |
| 61 | |
| 62 | if (features & IFF_ONE_QUEUE) { |
Peter Lieven | d26e445 | 2013-02-25 10:17:08 +0100 | [diff] [blame] | 63 | ifr.ifr_flags |= IFF_ONE_QUEUE; |
| 64 | } |
Mark McLoughlin | c28b1c1 | 2009-10-22 17:49:12 +0100 | [diff] [blame] | 65 | |
Peter Lieven | d26e445 | 2013-02-25 10:17:08 +0100 | [diff] [blame] | 66 | if (*vnet_hdr) { |
Kusanagi Kouichi | 1f149e7 | 2014-01-18 14:38:45 +0900 | [diff] [blame] | 67 | if (features & IFF_VNET_HDR) { |
Mark McLoughlin | c28b1c1 | 2009-10-22 17:49:12 +0100 | [diff] [blame] | 68 | *vnet_hdr = 1; |
| 69 | ifr.ifr_flags |= IFF_VNET_HDR; |
Pierre Riteau | 6720b35 | 2009-11-25 18:49:34 +0000 | [diff] [blame] | 70 | } else { |
| 71 | *vnet_hdr = 0; |
Mark McLoughlin | c28b1c1 | 2009-10-22 17:49:12 +0100 | [diff] [blame] | 72 | } |
| 73 | |
| 74 | if (vnet_hdr_required && !*vnet_hdr) { |
Markus Armbruster | 47896e2 | 2015-05-15 13:58:59 +0200 | [diff] [blame] | 75 | error_setg(errp, "vnet_hdr=1 requested, but no kernel " |
| 76 | "support for IFF_VNET_HDR available"); |
Mark McLoughlin | c28b1c1 | 2009-10-22 17:49:12 +0100 | [diff] [blame] | 77 | close(fd); |
| 78 | return -1; |
| 79 | } |
Michael S. Tsirkin | 89e6d68 | 2012-11-12 09:13:04 +0200 | [diff] [blame] | 80 | /* |
| 81 | * Make sure vnet header size has the default value: for a persistent |
| 82 | * tap it might have been modified e.g. by another instance of qemu. |
| 83 | * Ignore errors since old kernels do not support this ioctl: in this |
| 84 | * case the header size implicitly has the correct value. |
| 85 | */ |
| 86 | ioctl(fd, TUNSETVNETHDRSZ, &len); |
Mark McLoughlin | c28b1c1 | 2009-10-22 17:49:12 +0100 | [diff] [blame] | 87 | } |
| 88 | |
Jason Wang | 94fdc6d | 2013-01-30 19:12:31 +0800 | [diff] [blame] | 89 | if (mq_required) { |
Kusanagi Kouichi | 1f149e7 | 2014-01-18 14:38:45 +0900 | [diff] [blame] | 90 | if (!(features & IFF_MULTI_QUEUE)) { |
Markus Armbruster | 47896e2 | 2015-05-15 13:58:59 +0200 | [diff] [blame] | 91 | error_setg(errp, "multiqueue required, but no kernel " |
| 92 | "support for IFF_MULTI_QUEUE available"); |
Jason Wang | 94fdc6d | 2013-01-30 19:12:31 +0800 | [diff] [blame] | 93 | close(fd); |
| 94 | return -1; |
| 95 | } else { |
| 96 | ifr.ifr_flags |= IFF_MULTI_QUEUE; |
| 97 | } |
| 98 | } |
| 99 | |
Mark McLoughlin | c28b1c1 | 2009-10-22 17:49:12 +0100 | [diff] [blame] | 100 | if (ifname[0] != '\0') |
| 101 | pstrcpy(ifr.ifr_name, IFNAMSIZ, ifname); |
| 102 | else |
| 103 | pstrcpy(ifr.ifr_name, IFNAMSIZ, "tap%d"); |
| 104 | ret = ioctl(fd, TUNSETIFF, (void *) &ifr); |
| 105 | if (ret != 0) { |
Luiz Capitulino | 93a7320 | 2011-10-14 15:05:10 -0300 | [diff] [blame] | 106 | if (ifname[0] != '\0') { |
Markus Armbruster | 47896e2 | 2015-05-15 13:58:59 +0200 | [diff] [blame] | 107 | error_setg_errno(errp, errno, "could not configure %s (%s)", |
| 108 | PATH_NET_TUN, ifr.ifr_name); |
Luiz Capitulino | 93a7320 | 2011-10-14 15:05:10 -0300 | [diff] [blame] | 109 | } else { |
Markus Armbruster | 47896e2 | 2015-05-15 13:58:59 +0200 | [diff] [blame] | 110 | error_setg_errno(errp, errno, "could not configure %s", |
| 111 | PATH_NET_TUN); |
Luiz Capitulino | 93a7320 | 2011-10-14 15:05:10 -0300 | [diff] [blame] | 112 | } |
Mark McLoughlin | c28b1c1 | 2009-10-22 17:49:12 +0100 | [diff] [blame] | 113 | close(fd); |
| 114 | return -1; |
| 115 | } |
| 116 | pstrcpy(ifname, ifname_size, ifr.ifr_name); |
| 117 | fcntl(fd, F_SETFL, O_NONBLOCK); |
| 118 | return fd; |
| 119 | } |
Mark McLoughlin | 15ac913 | 2009-10-22 17:49:13 +0100 | [diff] [blame] | 120 | |
Michael S. Tsirkin | f157ed2 | 2011-02-01 14:25:40 +0200 | [diff] [blame] | 121 | /* sndbuf implements a kind of flow control for tap. |
| 122 | * Unfortunately when it's enabled, and packets are sent |
| 123 | * to other guests on the same host, the receiver |
| 124 | * can lock up the transmitter indefinitely. |
| 125 | * |
| 126 | * To avoid packet loss, sndbuf should be set to a value lower than the tx |
| 127 | * queue capacity of any destination network interface. |
Mark McLoughlin | 15ac913 | 2009-10-22 17:49:13 +0100 | [diff] [blame] | 128 | * Ethernet NICs generally have txqueuelen=1000, so 1Mb is |
Michael S. Tsirkin | f157ed2 | 2011-02-01 14:25:40 +0200 | [diff] [blame] | 129 | * a good value, given a 1500 byte MTU. |
Mark McLoughlin | 15ac913 | 2009-10-22 17:49:13 +0100 | [diff] [blame] | 130 | */ |
Michael S. Tsirkin | f157ed2 | 2011-02-01 14:25:40 +0200 | [diff] [blame] | 131 | #define TAP_DEFAULT_SNDBUF 0 |
Mark McLoughlin | 15ac913 | 2009-10-22 17:49:13 +0100 | [diff] [blame] | 132 | |
Markus Armbruster | 80b832c | 2015-05-15 13:58:55 +0200 | [diff] [blame] | 133 | void tap_set_sndbuf(int fd, const NetdevTapOptions *tap, Error **errp) |
Mark McLoughlin | 15ac913 | 2009-10-22 17:49:13 +0100 | [diff] [blame] | 134 | { |
| 135 | int sndbuf; |
| 136 | |
Laszlo Ersek | 08c573a | 2012-07-17 16:17:19 +0200 | [diff] [blame] | 137 | sndbuf = !tap->has_sndbuf ? TAP_DEFAULT_SNDBUF : |
| 138 | tap->sndbuf > INT_MAX ? INT_MAX : |
| 139 | tap->sndbuf; |
| 140 | |
Mark McLoughlin | 15ac913 | 2009-10-22 17:49:13 +0100 | [diff] [blame] | 141 | if (!sndbuf) { |
| 142 | sndbuf = INT_MAX; |
| 143 | } |
| 144 | |
Laszlo Ersek | 08c573a | 2012-07-17 16:17:19 +0200 | [diff] [blame] | 145 | if (ioctl(fd, TUNSETSNDBUF, &sndbuf) == -1 && tap->has_sndbuf) { |
Markus Armbruster | 80b832c | 2015-05-15 13:58:55 +0200 | [diff] [blame] | 146 | error_setg_errno(errp, errno, "TUNSETSNDBUF ioctl failed"); |
Mark McLoughlin | 15ac913 | 2009-10-22 17:49:13 +0100 | [diff] [blame] | 147 | } |
Mark McLoughlin | 15ac913 | 2009-10-22 17:49:13 +0100 | [diff] [blame] | 148 | } |
Mark McLoughlin | dc69004 | 2009-10-22 17:49:14 +0100 | [diff] [blame] | 149 | |
| 150 | int tap_probe_vnet_hdr(int fd) |
| 151 | { |
| 152 | struct ifreq ifr; |
| 153 | |
| 154 | if (ioctl(fd, TUNGETIFF, &ifr) != 0) { |
Markus Armbruster | 1ecda02 | 2010-02-18 17:25:24 +0100 | [diff] [blame] | 155 | error_report("TUNGETIFF ioctl() failed: %s", strerror(errno)); |
Mark McLoughlin | dc69004 | 2009-10-22 17:49:14 +0100 | [diff] [blame] | 156 | return 0; |
| 157 | } |
| 158 | |
| 159 | return ifr.ifr_flags & IFF_VNET_HDR; |
| 160 | } |
Mark McLoughlin | 1faac1f | 2009-10-22 17:49:15 +0100 | [diff] [blame] | 161 | |
Mark McLoughlin | 9c28271 | 2009-10-22 17:49:16 +0100 | [diff] [blame] | 162 | int tap_probe_has_ufo(int fd) |
| 163 | { |
| 164 | unsigned offload; |
| 165 | |
| 166 | offload = TUN_F_CSUM | TUN_F_UFO; |
| 167 | |
| 168 | if (ioctl(fd, TUNSETOFFLOAD, offload) < 0) |
| 169 | return 0; |
| 170 | |
| 171 | return 1; |
| 172 | } |
| 173 | |
Michael S. Tsirkin | 445d892 | 2010-07-16 11:16:06 +0300 | [diff] [blame] | 174 | /* Verify that we can assign given length */ |
| 175 | int tap_probe_vnet_hdr_len(int fd, int len) |
| 176 | { |
| 177 | int orig; |
| 178 | if (ioctl(fd, TUNGETVNETHDRSZ, &orig) == -1) { |
| 179 | return 0; |
| 180 | } |
| 181 | if (ioctl(fd, TUNSETVNETHDRSZ, &len) == -1) { |
| 182 | return 0; |
| 183 | } |
| 184 | /* Restore original length: we can't handle failure. */ |
| 185 | if (ioctl(fd, TUNSETVNETHDRSZ, &orig) == -1) { |
| 186 | fprintf(stderr, "TUNGETVNETHDRSZ ioctl() failed: %s. Exiting.\n", |
| 187 | strerror(errno)); |
Jason Wang | 28a6589 | 2013-01-30 19:12:21 +0800 | [diff] [blame] | 188 | abort(); |
Michael S. Tsirkin | 445d892 | 2010-07-16 11:16:06 +0300 | [diff] [blame] | 189 | return -errno; |
| 190 | } |
| 191 | return 1; |
| 192 | } |
| 193 | |
| 194 | void tap_fd_set_vnet_hdr_len(int fd, int len) |
| 195 | { |
| 196 | if (ioctl(fd, TUNSETVNETHDRSZ, &len) == -1) { |
| 197 | fprintf(stderr, "TUNSETVNETHDRSZ ioctl() failed: %s. Exiting.\n", |
| 198 | strerror(errno)); |
Jason Wang | 28a6589 | 2013-01-30 19:12:21 +0800 | [diff] [blame] | 199 | abort(); |
Michael S. Tsirkin | 445d892 | 2010-07-16 11:16:06 +0300 | [diff] [blame] | 200 | } |
| 201 | } |
| 202 | |
Greg Kurz | c80cd6b | 2015-06-17 15:23:44 +0200 | [diff] [blame] | 203 | int tap_fd_set_vnet_le(int fd, int is_le) |
| 204 | { |
| 205 | int arg = is_le ? 1 : 0; |
| 206 | |
| 207 | if (!ioctl(fd, TUNSETVNETLE, &arg)) { |
| 208 | return 0; |
| 209 | } |
| 210 | |
| 211 | /* Check if our kernel supports TUNSETVNETLE */ |
| 212 | if (errno == EINVAL) { |
| 213 | return -errno; |
| 214 | } |
| 215 | |
John Snow | 594fd21 | 2015-06-29 16:56:26 -0400 | [diff] [blame] | 216 | error_report("TUNSETVNETLE ioctl() failed: %s.", strerror(errno)); |
Greg Kurz | c80cd6b | 2015-06-17 15:23:44 +0200 | [diff] [blame] | 217 | abort(); |
| 218 | } |
| 219 | |
| 220 | int tap_fd_set_vnet_be(int fd, int is_be) |
| 221 | { |
| 222 | int arg = is_be ? 1 : 0; |
| 223 | |
| 224 | if (!ioctl(fd, TUNSETVNETBE, &arg)) { |
| 225 | return 0; |
| 226 | } |
| 227 | |
| 228 | /* Check if our kernel supports TUNSETVNETBE */ |
| 229 | if (errno == EINVAL) { |
| 230 | return -errno; |
| 231 | } |
| 232 | |
John Snow | 594fd21 | 2015-06-29 16:56:26 -0400 | [diff] [blame] | 233 | error_report("TUNSETVNETBE ioctl() failed: %s.", strerror(errno)); |
Greg Kurz | c80cd6b | 2015-06-17 15:23:44 +0200 | [diff] [blame] | 234 | abort(); |
| 235 | } |
| 236 | |
Mark McLoughlin | 1faac1f | 2009-10-22 17:49:15 +0100 | [diff] [blame] | 237 | void tap_fd_set_offload(int fd, int csum, int tso4, |
| 238 | int tso6, int ecn, int ufo) |
| 239 | { |
| 240 | unsigned int offload = 0; |
| 241 | |
Pierre Riteau | 2e50326 | 2009-11-25 18:49:35 +0000 | [diff] [blame] | 242 | /* Check if our kernel supports TUNSETOFFLOAD */ |
| 243 | if (ioctl(fd, TUNSETOFFLOAD, 0) != 0 && errno == EINVAL) { |
| 244 | return; |
| 245 | } |
| 246 | |
Mark McLoughlin | 1faac1f | 2009-10-22 17:49:15 +0100 | [diff] [blame] | 247 | if (csum) { |
| 248 | offload |= TUN_F_CSUM; |
| 249 | if (tso4) |
| 250 | offload |= TUN_F_TSO4; |
| 251 | if (tso6) |
| 252 | offload |= TUN_F_TSO6; |
| 253 | if ((tso4 || tso6) && ecn) |
| 254 | offload |= TUN_F_TSO_ECN; |
| 255 | if (ufo) |
| 256 | offload |= TUN_F_UFO; |
| 257 | } |
| 258 | |
| 259 | if (ioctl(fd, TUNSETOFFLOAD, offload) != 0) { |
| 260 | offload &= ~TUN_F_UFO; |
| 261 | if (ioctl(fd, TUNSETOFFLOAD, offload) != 0) { |
| 262 | fprintf(stderr, "TUNSETOFFLOAD ioctl() failed: %s\n", |
| 263 | strerror(errno)); |
| 264 | } |
| 265 | } |
| 266 | } |
Jason Wang | 94fdc6d | 2013-01-30 19:12:31 +0800 | [diff] [blame] | 267 | |
| 268 | /* Enable a specific queue of tap. */ |
| 269 | int tap_fd_enable(int fd) |
| 270 | { |
| 271 | struct ifreq ifr; |
| 272 | int ret; |
| 273 | |
| 274 | memset(&ifr, 0, sizeof(ifr)); |
| 275 | |
| 276 | ifr.ifr_flags = IFF_ATTACH_QUEUE; |
| 277 | ret = ioctl(fd, TUNSETQUEUE, (void *) &ifr); |
| 278 | |
| 279 | if (ret != 0) { |
| 280 | error_report("could not enable queue"); |
| 281 | } |
| 282 | |
| 283 | return ret; |
| 284 | } |
| 285 | |
| 286 | /* Disable a specific queue of tap/ */ |
| 287 | int tap_fd_disable(int fd) |
| 288 | { |
| 289 | struct ifreq ifr; |
| 290 | int ret; |
| 291 | |
| 292 | memset(&ifr, 0, sizeof(ifr)); |
| 293 | |
| 294 | ifr.ifr_flags = IFF_DETACH_QUEUE; |
| 295 | ret = ioctl(fd, TUNSETQUEUE, (void *) &ifr); |
| 296 | |
| 297 | if (ret != 0) { |
| 298 | error_report("could not disable queue"); |
| 299 | } |
| 300 | |
| 301 | return ret; |
| 302 | } |
| 303 | |
Jason Wang | e5dc0b4 | 2013-01-30 19:12:33 +0800 | [diff] [blame] | 304 | int tap_fd_get_ifname(int fd, char *ifname) |
| 305 | { |
| 306 | struct ifreq ifr; |
| 307 | |
| 308 | if (ioctl(fd, TUNGETIFF, &ifr) != 0) { |
| 309 | error_report("TUNGETIFF ioctl() failed: %s", |
| 310 | strerror(errno)); |
| 311 | return -1; |
| 312 | } |
| 313 | |
| 314 | pstrcpy(ifname, sizeof(ifr.ifr_name), ifr.ifr_name); |
| 315 | return 0; |
| 316 | } |