Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Xenbus code for netif backend |
| 3 | * |
| 4 | * Copyright (C) 2005 Rusty Russell <rusty@rustcorp.com.au> |
| 5 | * Copyright (C) 2005 XenSource Ltd |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or modify |
| 8 | * it under the terms of the GNU General Public License as published by |
| 9 | * the Free Software Foundation; either version 2 of the License, or |
| 10 | * (at your option) any later version. |
| 11 | * |
| 12 | * This program is distributed in the hope that it will be useful, |
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | * GNU General Public License for more details. |
| 16 | * |
| 17 | * You should have received a copy of the GNU General Public License |
Jeff Kirsher | adf8d3f | 2013-12-06 06:28:47 -0800 | [diff] [blame] | 18 | * along with this program; if not, see <http://www.gnu.org/licenses/>. |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 19 | */ |
| 20 | |
| 21 | #include "common.h" |
Wei Liu | e9ce7cb | 2014-06-04 10:30:42 +0100 | [diff] [blame] | 22 | #include <linux/vmalloc.h> |
| 23 | #include <linux/rtnetlink.h> |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 24 | |
| 25 | struct backend_info { |
| 26 | struct xenbus_device *dev; |
| 27 | struct xenvif *vif; |
Paul Durrant | ea732df | 2013-09-26 12:09:52 +0100 | [diff] [blame] | 28 | |
| 29 | /* This is the state that will be reflected in xenstore when any |
| 30 | * active hotplug script completes. |
| 31 | */ |
| 32 | enum xenbus_state state; |
| 33 | |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 34 | enum xenbus_state frontend_state; |
| 35 | struct xenbus_watch hotplug_status_watch; |
Ian Campbell | 17938a6 | 2011-04-03 22:26:24 +0000 | [diff] [blame] | 36 | u8 have_hotplug_status_watch:1; |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 37 | }; |
| 38 | |
Wei Liu | e9ce7cb | 2014-06-04 10:30:42 +0100 | [diff] [blame] | 39 | static int connect_rings(struct backend_info *be, struct xenvif_queue *queue); |
| 40 | static void connect(struct backend_info *be); |
| 41 | static int read_xenbus_vif_flags(struct backend_info *be); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 42 | static void backend_create_xenvif(struct backend_info *be); |
| 43 | static void unregister_hotplug_status_watch(struct backend_info *be); |
David Vrabel | dc62cca | 2013-10-07 13:55:19 +0100 | [diff] [blame] | 44 | static void set_backend_state(struct backend_info *be, |
| 45 | enum xenbus_state state); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 46 | |
| 47 | static int netback_remove(struct xenbus_device *dev) |
| 48 | { |
| 49 | struct backend_info *be = dev_get_drvdata(&dev->dev); |
| 50 | |
David Vrabel | dc62cca | 2013-10-07 13:55:19 +0100 | [diff] [blame] | 51 | set_backend_state(be, XenbusStateClosed); |
| 52 | |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 53 | unregister_hotplug_status_watch(be); |
| 54 | if (be->vif) { |
| 55 | kobject_uevent(&dev->dev.kobj, KOBJ_OFFLINE); |
| 56 | xenbus_rm(XBT_NIL, dev->nodename, "hotplug-status"); |
Paul Durrant | 279f438 | 2013-09-17 17:46:08 +0100 | [diff] [blame] | 57 | xenvif_free(be->vif); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 58 | be->vif = NULL; |
| 59 | } |
| 60 | kfree(be); |
| 61 | dev_set_drvdata(&dev->dev, NULL); |
| 62 | return 0; |
| 63 | } |
| 64 | |
| 65 | |
| 66 | /** |
| 67 | * Entry point to this code when a new device is created. Allocate the basic |
| 68 | * structures and switch to InitWait. |
| 69 | */ |
| 70 | static int netback_probe(struct xenbus_device *dev, |
| 71 | const struct xenbus_device_id *id) |
| 72 | { |
| 73 | const char *message; |
| 74 | struct xenbus_transaction xbt; |
| 75 | int err; |
| 76 | int sg; |
| 77 | struct backend_info *be = kzalloc(sizeof(struct backend_info), |
| 78 | GFP_KERNEL); |
| 79 | if (!be) { |
| 80 | xenbus_dev_fatal(dev, -ENOMEM, |
| 81 | "allocating backend structure"); |
| 82 | return -ENOMEM; |
| 83 | } |
| 84 | |
| 85 | be->dev = dev; |
| 86 | dev_set_drvdata(&dev->dev, be); |
| 87 | |
| 88 | sg = 1; |
| 89 | |
| 90 | do { |
| 91 | err = xenbus_transaction_start(&xbt); |
| 92 | if (err) { |
| 93 | xenbus_dev_fatal(dev, err, "starting transaction"); |
| 94 | goto fail; |
| 95 | } |
| 96 | |
| 97 | err = xenbus_printf(xbt, dev->nodename, "feature-sg", "%d", sg); |
| 98 | if (err) { |
| 99 | message = "writing feature-sg"; |
| 100 | goto abort_transaction; |
| 101 | } |
| 102 | |
| 103 | err = xenbus_printf(xbt, dev->nodename, "feature-gso-tcpv4", |
| 104 | "%d", sg); |
| 105 | if (err) { |
| 106 | message = "writing feature-gso-tcpv4"; |
| 107 | goto abort_transaction; |
| 108 | } |
| 109 | |
Paul Durrant | a946858 | 2013-10-16 17:50:31 +0100 | [diff] [blame] | 110 | err = xenbus_printf(xbt, dev->nodename, "feature-gso-tcpv6", |
| 111 | "%d", sg); |
| 112 | if (err) { |
| 113 | message = "writing feature-gso-tcpv6"; |
| 114 | goto abort_transaction; |
| 115 | } |
| 116 | |
Paul Durrant | 2eba61d | 2013-10-16 17:50:29 +0100 | [diff] [blame] | 117 | /* We support partial checksum setup for IPv6 packets */ |
| 118 | err = xenbus_printf(xbt, dev->nodename, |
| 119 | "feature-ipv6-csum-offload", |
| 120 | "%d", 1); |
| 121 | if (err) { |
| 122 | message = "writing feature-ipv6-csum-offload"; |
| 123 | goto abort_transaction; |
| 124 | } |
| 125 | |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 126 | /* We support rx-copy path. */ |
| 127 | err = xenbus_printf(xbt, dev->nodename, |
| 128 | "feature-rx-copy", "%d", 1); |
| 129 | if (err) { |
| 130 | message = "writing feature-rx-copy"; |
| 131 | goto abort_transaction; |
| 132 | } |
| 133 | |
| 134 | /* |
| 135 | * We don't support rx-flip path (except old guests who don't |
| 136 | * grok this feature flag). |
| 137 | */ |
| 138 | err = xenbus_printf(xbt, dev->nodename, |
| 139 | "feature-rx-flip", "%d", 0); |
| 140 | if (err) { |
| 141 | message = "writing feature-rx-flip"; |
| 142 | goto abort_transaction; |
| 143 | } |
| 144 | |
| 145 | err = xenbus_transaction_end(xbt, 0); |
| 146 | } while (err == -EAGAIN); |
| 147 | |
| 148 | if (err) { |
| 149 | xenbus_dev_fatal(dev, err, "completing transaction"); |
| 150 | goto fail; |
| 151 | } |
| 152 | |
Wei Liu | e1f00a69 | 2013-05-22 06:34:45 +0000 | [diff] [blame] | 153 | /* |
| 154 | * Split event channels support, this is optional so it is not |
| 155 | * put inside the above loop. |
| 156 | */ |
| 157 | err = xenbus_printf(XBT_NIL, dev->nodename, |
| 158 | "feature-split-event-channels", |
| 159 | "%u", separate_tx_rx_irq); |
| 160 | if (err) |
Wei Liu | 8ef2c3b | 2013-07-02 00:08:54 +0100 | [diff] [blame] | 161 | pr_debug("Error writing feature-split-event-channels\n"); |
Wei Liu | e1f00a69 | 2013-05-22 06:34:45 +0000 | [diff] [blame] | 162 | |
Andrew J. Bennieston | 8d3d53b | 2014-06-04 10:30:43 +0100 | [diff] [blame] | 163 | /* Multi-queue support: This is an optional feature. */ |
| 164 | err = xenbus_printf(XBT_NIL, dev->nodename, |
| 165 | "multi-queue-max-queues", "%u", xenvif_max_queues); |
| 166 | if (err) |
| 167 | pr_debug("Error writing multi-queue-max-queues\n"); |
| 168 | |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 169 | err = xenbus_switch_state(dev, XenbusStateInitWait); |
| 170 | if (err) |
| 171 | goto fail; |
| 172 | |
Paul Durrant | ea732df | 2013-09-26 12:09:52 +0100 | [diff] [blame] | 173 | be->state = XenbusStateInitWait; |
| 174 | |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 175 | /* This kicks hotplug scripts, so do it immediately. */ |
| 176 | backend_create_xenvif(be); |
| 177 | |
| 178 | return 0; |
| 179 | |
| 180 | abort_transaction: |
| 181 | xenbus_transaction_end(xbt, 1); |
| 182 | xenbus_dev_fatal(dev, err, "%s", message); |
| 183 | fail: |
Wei Liu | 8ef2c3b | 2013-07-02 00:08:54 +0100 | [diff] [blame] | 184 | pr_debug("failed\n"); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 185 | netback_remove(dev); |
| 186 | return err; |
| 187 | } |
| 188 | |
| 189 | |
| 190 | /* |
| 191 | * Handle the creation of the hotplug script environment. We add the script |
| 192 | * and vif variables to the environment, for the benefit of the vif-* hotplug |
| 193 | * scripts. |
| 194 | */ |
| 195 | static int netback_uevent(struct xenbus_device *xdev, |
| 196 | struct kobj_uevent_env *env) |
| 197 | { |
| 198 | struct backend_info *be = dev_get_drvdata(&xdev->dev); |
| 199 | char *val; |
| 200 | |
| 201 | val = xenbus_read(XBT_NIL, xdev->nodename, "script", NULL); |
| 202 | if (IS_ERR(val)) { |
| 203 | int err = PTR_ERR(val); |
| 204 | xenbus_dev_fatal(xdev, err, "reading script"); |
| 205 | return err; |
| 206 | } else { |
| 207 | if (add_uevent_var(env, "script=%s", val)) { |
| 208 | kfree(val); |
| 209 | return -ENOMEM; |
| 210 | } |
| 211 | kfree(val); |
| 212 | } |
| 213 | |
| 214 | if (!be || !be->vif) |
| 215 | return 0; |
| 216 | |
| 217 | return add_uevent_var(env, "vif=%s", be->vif->dev->name); |
| 218 | } |
| 219 | |
| 220 | |
| 221 | static void backend_create_xenvif(struct backend_info *be) |
| 222 | { |
| 223 | int err; |
| 224 | long handle; |
| 225 | struct xenbus_device *dev = be->dev; |
| 226 | |
| 227 | if (be->vif != NULL) |
| 228 | return; |
| 229 | |
| 230 | err = xenbus_scanf(XBT_NIL, dev->nodename, "handle", "%li", &handle); |
| 231 | if (err != 1) { |
| 232 | xenbus_dev_fatal(dev, err, "reading handle"); |
| 233 | return; |
| 234 | } |
| 235 | |
| 236 | be->vif = xenvif_alloc(&dev->dev, dev->otherend_id, handle); |
| 237 | if (IS_ERR(be->vif)) { |
| 238 | err = PTR_ERR(be->vif); |
| 239 | be->vif = NULL; |
| 240 | xenbus_dev_fatal(dev, err, "creating interface"); |
| 241 | return; |
| 242 | } |
| 243 | |
| 244 | kobject_uevent(&dev->dev.kobj, KOBJ_ONLINE); |
| 245 | } |
| 246 | |
Paul Durrant | ea732df | 2013-09-26 12:09:52 +0100 | [diff] [blame] | 247 | static void backend_disconnect(struct backend_info *be) |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 248 | { |
Paul Durrant | 279f438 | 2013-09-17 17:46:08 +0100 | [diff] [blame] | 249 | if (be->vif) |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 250 | xenvif_disconnect(be->vif); |
Paul Durrant | 279f438 | 2013-09-17 17:46:08 +0100 | [diff] [blame] | 251 | } |
| 252 | |
Paul Durrant | ea732df | 2013-09-26 12:09:52 +0100 | [diff] [blame] | 253 | static void backend_connect(struct backend_info *be) |
Paul Durrant | 279f438 | 2013-09-17 17:46:08 +0100 | [diff] [blame] | 254 | { |
Paul Durrant | ea732df | 2013-09-26 12:09:52 +0100 | [diff] [blame] | 255 | if (be->vif) |
| 256 | connect(be); |
| 257 | } |
Paul Durrant | 279f438 | 2013-09-17 17:46:08 +0100 | [diff] [blame] | 258 | |
Paul Durrant | ea732df | 2013-09-26 12:09:52 +0100 | [diff] [blame] | 259 | static inline void backend_switch_state(struct backend_info *be, |
| 260 | enum xenbus_state state) |
| 261 | { |
| 262 | struct xenbus_device *dev = be->dev; |
| 263 | |
| 264 | pr_debug("%s -> %s\n", dev->nodename, xenbus_strstate(state)); |
| 265 | be->state = state; |
| 266 | |
| 267 | /* If we are waiting for a hotplug script then defer the |
| 268 | * actual xenbus state change. |
| 269 | */ |
| 270 | if (!be->have_hotplug_status_watch) |
| 271 | xenbus_switch_state(dev, state); |
| 272 | } |
| 273 | |
| 274 | /* Handle backend state transitions: |
| 275 | * |
| 276 | * The backend state starts in InitWait and the following transitions are |
| 277 | * allowed. |
| 278 | * |
| 279 | * InitWait -> Connected |
| 280 | * |
| 281 | * ^ \ | |
| 282 | * | \ | |
| 283 | * | \ | |
| 284 | * | \ | |
| 285 | * | \ | |
| 286 | * | \ | |
| 287 | * | V V |
| 288 | * |
| 289 | * Closed <-> Closing |
| 290 | * |
| 291 | * The state argument specifies the eventual state of the backend and the |
| 292 | * function transitions to that state via the shortest path. |
| 293 | */ |
| 294 | static void set_backend_state(struct backend_info *be, |
| 295 | enum xenbus_state state) |
| 296 | { |
| 297 | while (be->state != state) { |
| 298 | switch (be->state) { |
| 299 | case XenbusStateClosed: |
| 300 | switch (state) { |
| 301 | case XenbusStateInitWait: |
| 302 | case XenbusStateConnected: |
| 303 | pr_info("%s: prepare for reconnect\n", |
| 304 | be->dev->nodename); |
| 305 | backend_switch_state(be, XenbusStateInitWait); |
| 306 | break; |
| 307 | case XenbusStateClosing: |
| 308 | backend_switch_state(be, XenbusStateClosing); |
| 309 | break; |
| 310 | default: |
| 311 | BUG(); |
| 312 | } |
| 313 | break; |
| 314 | case XenbusStateInitWait: |
| 315 | switch (state) { |
| 316 | case XenbusStateConnected: |
| 317 | backend_connect(be); |
| 318 | backend_switch_state(be, XenbusStateConnected); |
| 319 | break; |
| 320 | case XenbusStateClosing: |
| 321 | case XenbusStateClosed: |
| 322 | backend_switch_state(be, XenbusStateClosing); |
| 323 | break; |
| 324 | default: |
| 325 | BUG(); |
| 326 | } |
| 327 | break; |
| 328 | case XenbusStateConnected: |
| 329 | switch (state) { |
| 330 | case XenbusStateInitWait: |
| 331 | case XenbusStateClosing: |
| 332 | case XenbusStateClosed: |
| 333 | backend_disconnect(be); |
| 334 | backend_switch_state(be, XenbusStateClosing); |
| 335 | break; |
| 336 | default: |
| 337 | BUG(); |
| 338 | } |
| 339 | break; |
| 340 | case XenbusStateClosing: |
| 341 | switch (state) { |
| 342 | case XenbusStateInitWait: |
| 343 | case XenbusStateConnected: |
| 344 | case XenbusStateClosed: |
| 345 | backend_switch_state(be, XenbusStateClosed); |
| 346 | break; |
| 347 | default: |
| 348 | BUG(); |
| 349 | } |
| 350 | break; |
| 351 | default: |
| 352 | BUG(); |
| 353 | } |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 354 | } |
| 355 | } |
| 356 | |
| 357 | /** |
| 358 | * Callback received when the frontend's state changes. |
| 359 | */ |
| 360 | static void frontend_changed(struct xenbus_device *dev, |
| 361 | enum xenbus_state frontend_state) |
| 362 | { |
| 363 | struct backend_info *be = dev_get_drvdata(&dev->dev); |
| 364 | |
Paul Durrant | ea732df | 2013-09-26 12:09:52 +0100 | [diff] [blame] | 365 | pr_debug("%s -> %s\n", dev->otherend, xenbus_strstate(frontend_state)); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 366 | |
| 367 | be->frontend_state = frontend_state; |
| 368 | |
| 369 | switch (frontend_state) { |
| 370 | case XenbusStateInitialising: |
Paul Durrant | ea732df | 2013-09-26 12:09:52 +0100 | [diff] [blame] | 371 | set_backend_state(be, XenbusStateInitWait); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 372 | break; |
| 373 | |
| 374 | case XenbusStateInitialised: |
| 375 | break; |
| 376 | |
| 377 | case XenbusStateConnected: |
Paul Durrant | ea732df | 2013-09-26 12:09:52 +0100 | [diff] [blame] | 378 | set_backend_state(be, XenbusStateConnected); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 379 | break; |
| 380 | |
| 381 | case XenbusStateClosing: |
Paul Durrant | ea732df | 2013-09-26 12:09:52 +0100 | [diff] [blame] | 382 | set_backend_state(be, XenbusStateClosing); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 383 | break; |
| 384 | |
| 385 | case XenbusStateClosed: |
Paul Durrant | ea732df | 2013-09-26 12:09:52 +0100 | [diff] [blame] | 386 | set_backend_state(be, XenbusStateClosed); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 387 | if (xenbus_dev_is_online(dev)) |
| 388 | break; |
| 389 | /* fall through if not online */ |
| 390 | case XenbusStateUnknown: |
Paul Durrant | ea732df | 2013-09-26 12:09:52 +0100 | [diff] [blame] | 391 | set_backend_state(be, XenbusStateClosed); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 392 | device_unregister(&dev->dev); |
| 393 | break; |
| 394 | |
| 395 | default: |
| 396 | xenbus_dev_fatal(dev, -EINVAL, "saw state %d at frontend", |
| 397 | frontend_state); |
| 398 | break; |
| 399 | } |
| 400 | } |
| 401 | |
| 402 | |
| 403 | static void xen_net_read_rate(struct xenbus_device *dev, |
| 404 | unsigned long *bytes, unsigned long *usec) |
| 405 | { |
| 406 | char *s, *e; |
| 407 | unsigned long b, u; |
| 408 | char *ratestr; |
| 409 | |
| 410 | /* Default to unlimited bandwidth. */ |
| 411 | *bytes = ~0UL; |
| 412 | *usec = 0; |
| 413 | |
| 414 | ratestr = xenbus_read(XBT_NIL, dev->nodename, "rate", NULL); |
| 415 | if (IS_ERR(ratestr)) |
| 416 | return; |
| 417 | |
| 418 | s = ratestr; |
| 419 | b = simple_strtoul(s, &e, 10); |
| 420 | if ((s == e) || (*e != ',')) |
| 421 | goto fail; |
| 422 | |
| 423 | s = e + 1; |
| 424 | u = simple_strtoul(s, &e, 10); |
| 425 | if ((s == e) || (*e != '\0')) |
| 426 | goto fail; |
| 427 | |
| 428 | *bytes = b; |
| 429 | *usec = u; |
| 430 | |
| 431 | kfree(ratestr); |
| 432 | return; |
| 433 | |
| 434 | fail: |
| 435 | pr_warn("Failed to parse network rate limit. Traffic unlimited.\n"); |
| 436 | kfree(ratestr); |
| 437 | } |
| 438 | |
| 439 | static int xen_net_read_mac(struct xenbus_device *dev, u8 mac[]) |
| 440 | { |
| 441 | char *s, *e, *macstr; |
| 442 | int i; |
| 443 | |
| 444 | macstr = s = xenbus_read(XBT_NIL, dev->nodename, "mac", NULL); |
| 445 | if (IS_ERR(macstr)) |
| 446 | return PTR_ERR(macstr); |
| 447 | |
| 448 | for (i = 0; i < ETH_ALEN; i++) { |
| 449 | mac[i] = simple_strtoul(s, &e, 16); |
| 450 | if ((s == e) || (*e != ((i == ETH_ALEN-1) ? '\0' : ':'))) { |
| 451 | kfree(macstr); |
| 452 | return -ENOENT; |
| 453 | } |
| 454 | s = e+1; |
| 455 | } |
| 456 | |
| 457 | kfree(macstr); |
| 458 | return 0; |
| 459 | } |
| 460 | |
| 461 | static void unregister_hotplug_status_watch(struct backend_info *be) |
| 462 | { |
| 463 | if (be->have_hotplug_status_watch) { |
| 464 | unregister_xenbus_watch(&be->hotplug_status_watch); |
| 465 | kfree(be->hotplug_status_watch.node); |
| 466 | } |
| 467 | be->have_hotplug_status_watch = 0; |
| 468 | } |
| 469 | |
| 470 | static void hotplug_status_changed(struct xenbus_watch *watch, |
| 471 | const char **vec, |
| 472 | unsigned int vec_size) |
| 473 | { |
| 474 | struct backend_info *be = container_of(watch, |
| 475 | struct backend_info, |
| 476 | hotplug_status_watch); |
| 477 | char *str; |
| 478 | unsigned int len; |
| 479 | |
| 480 | str = xenbus_read(XBT_NIL, be->dev->nodename, "hotplug-status", &len); |
| 481 | if (IS_ERR(str)) |
| 482 | return; |
| 483 | if (len == sizeof("connected")-1 && !memcmp(str, "connected", len)) { |
Paul Durrant | ea732df | 2013-09-26 12:09:52 +0100 | [diff] [blame] | 484 | /* Complete any pending state change */ |
| 485 | xenbus_switch_state(be->dev, be->state); |
| 486 | |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 487 | /* Not interested in this watch anymore. */ |
| 488 | unregister_hotplug_status_watch(be); |
| 489 | } |
| 490 | kfree(str); |
| 491 | } |
| 492 | |
| 493 | static void connect(struct backend_info *be) |
| 494 | { |
| 495 | int err; |
| 496 | struct xenbus_device *dev = be->dev; |
Wei Liu | e9ce7cb | 2014-06-04 10:30:42 +0100 | [diff] [blame] | 497 | unsigned long credit_bytes, credit_usec; |
| 498 | unsigned int queue_index; |
Andrew J. Bennieston | 8d3d53b | 2014-06-04 10:30:43 +0100 | [diff] [blame] | 499 | unsigned int requested_num_queues; |
Wei Liu | e9ce7cb | 2014-06-04 10:30:42 +0100 | [diff] [blame] | 500 | struct xenvif_queue *queue; |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 501 | |
Andrew J. Bennieston | 8d3d53b | 2014-06-04 10:30:43 +0100 | [diff] [blame] | 502 | /* Check whether the frontend requested multiple queues |
| 503 | * and read the number requested. |
| 504 | */ |
| 505 | err = xenbus_scanf(XBT_NIL, dev->otherend, |
| 506 | "multi-queue-num-queues", |
| 507 | "%u", &requested_num_queues); |
| 508 | if (err < 0) { |
| 509 | requested_num_queues = 1; /* Fall back to single queue */ |
| 510 | } else if (requested_num_queues > xenvif_max_queues) { |
| 511 | /* buggy or malicious guest */ |
| 512 | xenbus_dev_fatal(dev, err, |
| 513 | "guest requested %u queues, exceeding the maximum of %u.", |
| 514 | requested_num_queues, xenvif_max_queues); |
| 515 | return; |
| 516 | } |
| 517 | |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 518 | err = xen_net_read_mac(dev, be->vif->fe_dev_addr); |
| 519 | if (err) { |
| 520 | xenbus_dev_fatal(dev, err, "parsing %s/mac", dev->nodename); |
| 521 | return; |
| 522 | } |
| 523 | |
Wei Liu | e9ce7cb | 2014-06-04 10:30:42 +0100 | [diff] [blame] | 524 | xen_net_read_rate(dev, &credit_bytes, &credit_usec); |
| 525 | read_xenbus_vif_flags(be); |
| 526 | |
Andrew J. Bennieston | 8d3d53b | 2014-06-04 10:30:43 +0100 | [diff] [blame] | 527 | /* Use the number of queues requested by the frontend */ |
Wei Liu | e9ce7cb | 2014-06-04 10:30:42 +0100 | [diff] [blame] | 528 | be->vif->queues = vzalloc(requested_num_queues * |
| 529 | sizeof(struct xenvif_queue)); |
| 530 | rtnl_lock(); |
| 531 | netif_set_real_num_tx_queues(be->vif->dev, requested_num_queues); |
| 532 | rtnl_unlock(); |
| 533 | |
| 534 | for (queue_index = 0; queue_index < requested_num_queues; ++queue_index) { |
| 535 | queue = &be->vif->queues[queue_index]; |
| 536 | queue->vif = be->vif; |
| 537 | queue->id = queue_index; |
| 538 | snprintf(queue->name, sizeof(queue->name), "%s-q%u", |
| 539 | be->vif->dev->name, queue->id); |
| 540 | |
| 541 | err = xenvif_init_queue(queue); |
Andrew J. Bennieston | 8d3d53b | 2014-06-04 10:30:43 +0100 | [diff] [blame] | 542 | if (err) { |
| 543 | /* xenvif_init_queue() cleans up after itself on |
| 544 | * failure, but we need to clean up any previously |
| 545 | * initialised queues. Set num_queues to i so that |
| 546 | * earlier queues can be destroyed using the regular |
| 547 | * disconnect logic. |
| 548 | */ |
| 549 | rtnl_lock(); |
| 550 | netif_set_real_num_tx_queues(be->vif->dev, queue_index); |
| 551 | rtnl_unlock(); |
Wei Liu | e9ce7cb | 2014-06-04 10:30:42 +0100 | [diff] [blame] | 552 | goto err; |
Andrew J. Bennieston | 8d3d53b | 2014-06-04 10:30:43 +0100 | [diff] [blame] | 553 | } |
Wei Liu | e9ce7cb | 2014-06-04 10:30:42 +0100 | [diff] [blame] | 554 | |
| 555 | queue->remaining_credit = credit_bytes; |
| 556 | |
| 557 | err = connect_rings(be, queue); |
Andrew J. Bennieston | 8d3d53b | 2014-06-04 10:30:43 +0100 | [diff] [blame] | 558 | if (err) { |
| 559 | /* connect_rings() cleans up after itself on failure, |
| 560 | * but we need to clean up after xenvif_init_queue() here, |
| 561 | * and also clean up any previously initialised queues. |
| 562 | */ |
| 563 | xenvif_deinit_queue(queue); |
| 564 | rtnl_lock(); |
| 565 | netif_set_real_num_tx_queues(be->vif->dev, queue_index); |
| 566 | rtnl_unlock(); |
Wei Liu | e9ce7cb | 2014-06-04 10:30:42 +0100 | [diff] [blame] | 567 | goto err; |
Andrew J. Bennieston | 8d3d53b | 2014-06-04 10:30:43 +0100 | [diff] [blame] | 568 | } |
Wei Liu | e9ce7cb | 2014-06-04 10:30:42 +0100 | [diff] [blame] | 569 | } |
| 570 | |
| 571 | xenvif_carrier_on(be->vif); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 572 | |
| 573 | unregister_hotplug_status_watch(be); |
| 574 | err = xenbus_watch_pathfmt(dev, &be->hotplug_status_watch, |
| 575 | hotplug_status_changed, |
| 576 | "%s/%s", dev->nodename, "hotplug-status"); |
Paul Durrant | ea732df | 2013-09-26 12:09:52 +0100 | [diff] [blame] | 577 | if (!err) |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 578 | be->have_hotplug_status_watch = 1; |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 579 | |
Wei Liu | e9ce7cb | 2014-06-04 10:30:42 +0100 | [diff] [blame] | 580 | netif_tx_wake_all_queues(be->vif->dev); |
| 581 | |
| 582 | return; |
| 583 | |
| 584 | err: |
Andrew J. Bennieston | 8d3d53b | 2014-06-04 10:30:43 +0100 | [diff] [blame] | 585 | if (be->vif->dev->real_num_tx_queues > 0) |
| 586 | xenvif_disconnect(be->vif); /* Clean up existing queues */ |
Wei Liu | e9ce7cb | 2014-06-04 10:30:42 +0100 | [diff] [blame] | 587 | vfree(be->vif->queues); |
| 588 | be->vif->queues = NULL; |
| 589 | rtnl_lock(); |
| 590 | netif_set_real_num_tx_queues(be->vif->dev, 0); |
| 591 | rtnl_unlock(); |
| 592 | return; |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 593 | } |
| 594 | |
| 595 | |
Wei Liu | e9ce7cb | 2014-06-04 10:30:42 +0100 | [diff] [blame] | 596 | static int connect_rings(struct backend_info *be, struct xenvif_queue *queue) |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 597 | { |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 598 | struct xenbus_device *dev = be->dev; |
Andrew J. Bennieston | 8d3d53b | 2014-06-04 10:30:43 +0100 | [diff] [blame] | 599 | unsigned int num_queues = queue->vif->dev->real_num_tx_queues; |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 600 | unsigned long tx_ring_ref, rx_ring_ref; |
Wei Liu | e9ce7cb | 2014-06-04 10:30:42 +0100 | [diff] [blame] | 601 | unsigned int tx_evtchn, rx_evtchn; |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 602 | int err; |
Andrew J. Bennieston | 8d3d53b | 2014-06-04 10:30:43 +0100 | [diff] [blame] | 603 | char *xspath; |
| 604 | size_t xspathsize; |
| 605 | const size_t xenstore_path_ext_size = 11; /* sufficient for "/queue-NNN" */ |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 606 | |
Andrew J. Bennieston | 8d3d53b | 2014-06-04 10:30:43 +0100 | [diff] [blame] | 607 | /* If the frontend requested 1 queue, or we have fallen back |
| 608 | * to single queue due to lack of frontend support for multi- |
| 609 | * queue, expect the remaining XenStore keys in the toplevel |
| 610 | * directory. Otherwise, expect them in a subdirectory called |
| 611 | * queue-N. |
| 612 | */ |
| 613 | if (num_queues == 1) { |
| 614 | xspath = kzalloc(strlen(dev->otherend) + 1, GFP_KERNEL); |
| 615 | if (!xspath) { |
| 616 | xenbus_dev_fatal(dev, -ENOMEM, |
| 617 | "reading ring references"); |
| 618 | return -ENOMEM; |
| 619 | } |
| 620 | strcpy(xspath, dev->otherend); |
| 621 | } else { |
| 622 | xspathsize = strlen(dev->otherend) + xenstore_path_ext_size; |
| 623 | xspath = kzalloc(xspathsize, GFP_KERNEL); |
| 624 | if (!xspath) { |
| 625 | xenbus_dev_fatal(dev, -ENOMEM, |
| 626 | "reading ring references"); |
| 627 | return -ENOMEM; |
| 628 | } |
| 629 | snprintf(xspath, xspathsize, "%s/queue-%u", dev->otherend, |
| 630 | queue->id); |
| 631 | } |
| 632 | |
| 633 | err = xenbus_gather(XBT_NIL, xspath, |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 634 | "tx-ring-ref", "%lu", &tx_ring_ref, |
Wei Liu | e1f00a69 | 2013-05-22 06:34:45 +0000 | [diff] [blame] | 635 | "rx-ring-ref", "%lu", &rx_ring_ref, NULL); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 636 | if (err) { |
| 637 | xenbus_dev_fatal(dev, err, |
Wei Liu | e1f00a69 | 2013-05-22 06:34:45 +0000 | [diff] [blame] | 638 | "reading %s/ring-ref", |
Andrew J. Bennieston | 8d3d53b | 2014-06-04 10:30:43 +0100 | [diff] [blame] | 639 | xspath); |
| 640 | goto err; |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 641 | } |
| 642 | |
Wei Liu | e1f00a69 | 2013-05-22 06:34:45 +0000 | [diff] [blame] | 643 | /* Try split event channels first, then single event channel. */ |
Andrew J. Bennieston | 8d3d53b | 2014-06-04 10:30:43 +0100 | [diff] [blame] | 644 | err = xenbus_gather(XBT_NIL, xspath, |
Wei Liu | e1f00a69 | 2013-05-22 06:34:45 +0000 | [diff] [blame] | 645 | "event-channel-tx", "%u", &tx_evtchn, |
| 646 | "event-channel-rx", "%u", &rx_evtchn, NULL); |
| 647 | if (err < 0) { |
Andrew J. Bennieston | 8d3d53b | 2014-06-04 10:30:43 +0100 | [diff] [blame] | 648 | err = xenbus_scanf(XBT_NIL, xspath, |
Wei Liu | e1f00a69 | 2013-05-22 06:34:45 +0000 | [diff] [blame] | 649 | "event-channel", "%u", &tx_evtchn); |
| 650 | if (err < 0) { |
| 651 | xenbus_dev_fatal(dev, err, |
| 652 | "reading %s/event-channel(-tx/rx)", |
Andrew J. Bennieston | 8d3d53b | 2014-06-04 10:30:43 +0100 | [diff] [blame] | 653 | xspath); |
| 654 | goto err; |
Wei Liu | e1f00a69 | 2013-05-22 06:34:45 +0000 | [diff] [blame] | 655 | } |
| 656 | rx_evtchn = tx_evtchn; |
| 657 | } |
| 658 | |
Wei Liu | e9ce7cb | 2014-06-04 10:30:42 +0100 | [diff] [blame] | 659 | /* Map the shared frame, irq etc. */ |
| 660 | err = xenvif_connect(queue, tx_ring_ref, rx_ring_ref, |
| 661 | tx_evtchn, rx_evtchn); |
| 662 | if (err) { |
| 663 | xenbus_dev_fatal(dev, err, |
| 664 | "mapping shared-frames %lu/%lu port tx %u rx %u", |
| 665 | tx_ring_ref, rx_ring_ref, |
| 666 | tx_evtchn, rx_evtchn); |
Andrew J. Bennieston | 8d3d53b | 2014-06-04 10:30:43 +0100 | [diff] [blame] | 667 | goto err; |
Wei Liu | e9ce7cb | 2014-06-04 10:30:42 +0100 | [diff] [blame] | 668 | } |
| 669 | |
Andrew J. Bennieston | 8d3d53b | 2014-06-04 10:30:43 +0100 | [diff] [blame] | 670 | err = 0; |
| 671 | err: /* Regular return falls through with err == 0 */ |
| 672 | kfree(xspath); |
| 673 | return err; |
Wei Liu | e9ce7cb | 2014-06-04 10:30:42 +0100 | [diff] [blame] | 674 | } |
| 675 | |
| 676 | static int read_xenbus_vif_flags(struct backend_info *be) |
| 677 | { |
| 678 | struct xenvif *vif = be->vif; |
| 679 | struct xenbus_device *dev = be->dev; |
| 680 | unsigned int rx_copy; |
| 681 | int err, val; |
| 682 | |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 683 | err = xenbus_scanf(XBT_NIL, dev->otherend, "request-rx-copy", "%u", |
| 684 | &rx_copy); |
| 685 | if (err == -ENOENT) { |
| 686 | err = 0; |
| 687 | rx_copy = 0; |
| 688 | } |
| 689 | if (err < 0) { |
| 690 | xenbus_dev_fatal(dev, err, "reading %s/request-rx-copy", |
| 691 | dev->otherend); |
| 692 | return err; |
| 693 | } |
| 694 | if (!rx_copy) |
| 695 | return -EOPNOTSUPP; |
| 696 | |
| 697 | if (vif->dev->tx_queue_len != 0) { |
| 698 | if (xenbus_scanf(XBT_NIL, dev->otherend, |
| 699 | "feature-rx-notify", "%d", &val) < 0) |
| 700 | val = 0; |
| 701 | if (val) |
| 702 | vif->can_queue = 1; |
| 703 | else |
| 704 | /* Must be non-zero for pfifo_fast to work. */ |
| 705 | vif->dev->tx_queue_len = 1; |
| 706 | } |
| 707 | |
| 708 | if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-sg", |
| 709 | "%d", &val) < 0) |
| 710 | val = 0; |
| 711 | vif->can_sg = !!val; |
| 712 | |
Paul Durrant | 82cada2 | 2013-10-16 17:50:32 +0100 | [diff] [blame] | 713 | vif->gso_mask = 0; |
| 714 | vif->gso_prefix_mask = 0; |
| 715 | |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 716 | if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-gso-tcpv4", |
| 717 | "%d", &val) < 0) |
| 718 | val = 0; |
Paul Durrant | 82cada2 | 2013-10-16 17:50:32 +0100 | [diff] [blame] | 719 | if (val) |
| 720 | vif->gso_mask |= GSO_BIT(TCPV4); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 721 | |
| 722 | if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-gso-tcpv4-prefix", |
| 723 | "%d", &val) < 0) |
| 724 | val = 0; |
Paul Durrant | 82cada2 | 2013-10-16 17:50:32 +0100 | [diff] [blame] | 725 | if (val) |
| 726 | vif->gso_prefix_mask |= GSO_BIT(TCPV4); |
| 727 | |
| 728 | if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-gso-tcpv6", |
| 729 | "%d", &val) < 0) |
| 730 | val = 0; |
| 731 | if (val) |
| 732 | vif->gso_mask |= GSO_BIT(TCPV6); |
| 733 | |
| 734 | if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-gso-tcpv6-prefix", |
| 735 | "%d", &val) < 0) |
| 736 | val = 0; |
| 737 | if (val) |
| 738 | vif->gso_prefix_mask |= GSO_BIT(TCPV6); |
| 739 | |
| 740 | if (vif->gso_mask & vif->gso_prefix_mask) { |
| 741 | xenbus_dev_fatal(dev, err, |
| 742 | "%s: gso and gso prefix flags are not " |
| 743 | "mutually exclusive", |
| 744 | dev->otherend); |
| 745 | return -EOPNOTSUPP; |
| 746 | } |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 747 | |
| 748 | if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-no-csum-offload", |
| 749 | "%d", &val) < 0) |
| 750 | val = 0; |
Paul Durrant | 146c8a7 | 2013-10-16 17:50:28 +0100 | [diff] [blame] | 751 | vif->ip_csum = !val; |
| 752 | |
| 753 | if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-ipv6-csum-offload", |
| 754 | "%d", &val) < 0) |
| 755 | val = 0; |
| 756 | vif->ipv6_csum = !!val; |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 757 | |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 758 | return 0; |
| 759 | } |
| 760 | |
| 761 | |
| 762 | /* ** Driver Registration ** */ |
| 763 | |
| 764 | |
| 765 | static const struct xenbus_device_id netback_ids[] = { |
| 766 | { "vif" }, |
| 767 | { "" } |
| 768 | }; |
| 769 | |
| 770 | |
Jan Beulich | 73db144 | 2011-12-22 09:08:13 +0000 | [diff] [blame] | 771 | static DEFINE_XENBUS_DRIVER(netback, , |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 772 | .probe = netback_probe, |
| 773 | .remove = netback_remove, |
| 774 | .uevent = netback_uevent, |
| 775 | .otherend_changed = frontend_changed, |
Jan Beulich | 73db144 | 2011-12-22 09:08:13 +0000 | [diff] [blame] | 776 | ); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 777 | |
| 778 | int xenvif_xenbus_init(void) |
| 779 | { |
Jan Beulich | 73db144 | 2011-12-22 09:08:13 +0000 | [diff] [blame] | 780 | return xenbus_register_backend(&netback_driver); |
Ian Campbell | f942dc2 | 2011-03-15 00:06:18 +0000 | [diff] [blame] | 781 | } |
Wei Liu | b103f35 | 2013-05-16 23:26:11 +0000 | [diff] [blame] | 782 | |
| 783 | void xenvif_xenbus_fini(void) |
| 784 | { |
| 785 | return xenbus_unregister_driver(&netback_driver); |
| 786 | } |