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Commit | Line | Data |
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f942dc25 IC |
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 | |
adf8d3ff | 18 | * along with this program; if not, see <http://www.gnu.org/licenses/>. |
f942dc25 IC |
19 | */ |
20 | ||
21 | #include "common.h" | |
e9ce7cb6 WL |
22 | #include <linux/vmalloc.h> |
23 | #include <linux/rtnetlink.h> | |
f942dc25 IC |
24 | |
25 | struct backend_info { | |
26 | struct xenbus_device *dev; | |
27 | struct xenvif *vif; | |
ea732dff PD |
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 | ||
f942dc25 IC |
34 | enum xenbus_state frontend_state; |
35 | struct xenbus_watch hotplug_status_watch; | |
17938a69 | 36 | u8 have_hotplug_status_watch:1; |
f942dc25 IC |
37 | }; |
38 | ||
e9ce7cb6 WL |
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); | |
2dd34339 | 42 | static int backend_create_xenvif(struct backend_info *be); |
f942dc25 | 43 | static void unregister_hotplug_status_watch(struct backend_info *be); |
dc62ccac DV |
44 | static void set_backend_state(struct backend_info *be, |
45 | enum xenbus_state state); | |
f942dc25 | 46 | |
f51de243 ZK |
47 | #ifdef CONFIG_DEBUG_FS |
48 | struct dentry *xen_netback_dbg_root = NULL; | |
49 | ||
50 | static int xenvif_read_io_ring(struct seq_file *m, void *v) | |
51 | { | |
52 | struct xenvif_queue *queue = m->private; | |
53 | struct xen_netif_tx_back_ring *tx_ring = &queue->tx; | |
54 | struct xen_netif_rx_back_ring *rx_ring = &queue->rx; | |
f48da8b1 | 55 | struct netdev_queue *dev_queue; |
f51de243 ZK |
56 | |
57 | if (tx_ring->sring) { | |
58 | struct xen_netif_tx_sring *sring = tx_ring->sring; | |
59 | ||
60 | seq_printf(m, "Queue %d\nTX: nr_ents %u\n", queue->id, | |
61 | tx_ring->nr_ents); | |
62 | seq_printf(m, "req prod %u (%d) cons %u (%d) event %u (%d)\n", | |
63 | sring->req_prod, | |
64 | sring->req_prod - sring->rsp_prod, | |
65 | tx_ring->req_cons, | |
66 | tx_ring->req_cons - sring->rsp_prod, | |
67 | sring->req_event, | |
68 | sring->req_event - sring->rsp_prod); | |
69 | seq_printf(m, "rsp prod %u (base) pvt %u (%d) event %u (%d)\n", | |
70 | sring->rsp_prod, | |
71 | tx_ring->rsp_prod_pvt, | |
72 | tx_ring->rsp_prod_pvt - sring->rsp_prod, | |
73 | sring->rsp_event, | |
74 | sring->rsp_event - sring->rsp_prod); | |
75 | seq_printf(m, "pending prod %u pending cons %u nr_pending_reqs %u\n", | |
76 | queue->pending_prod, | |
77 | queue->pending_cons, | |
78 | nr_pending_reqs(queue)); | |
79 | seq_printf(m, "dealloc prod %u dealloc cons %u dealloc_queue %u\n\n", | |
80 | queue->dealloc_prod, | |
81 | queue->dealloc_cons, | |
82 | queue->dealloc_prod - queue->dealloc_cons); | |
83 | } | |
84 | ||
85 | if (rx_ring->sring) { | |
86 | struct xen_netif_rx_sring *sring = rx_ring->sring; | |
87 | ||
88 | seq_printf(m, "RX: nr_ents %u\n", rx_ring->nr_ents); | |
89 | seq_printf(m, "req prod %u (%d) cons %u (%d) event %u (%d)\n", | |
90 | sring->req_prod, | |
91 | sring->req_prod - sring->rsp_prod, | |
92 | rx_ring->req_cons, | |
93 | rx_ring->req_cons - sring->rsp_prod, | |
94 | sring->req_event, | |
95 | sring->req_event - sring->rsp_prod); | |
96 | seq_printf(m, "rsp prod %u (base) pvt %u (%d) event %u (%d)\n\n", | |
97 | sring->rsp_prod, | |
98 | rx_ring->rsp_prod_pvt, | |
99 | rx_ring->rsp_prod_pvt - sring->rsp_prod, | |
100 | sring->rsp_event, | |
101 | sring->rsp_event - sring->rsp_prod); | |
102 | } | |
103 | ||
104 | seq_printf(m, "NAPI state: %lx NAPI weight: %d TX queue len %u\n" | |
105 | "Credit timer_pending: %d, credit: %lu, usec: %lu\n" | |
106 | "remaining: %lu, expires: %lu, now: %lu\n", | |
107 | queue->napi.state, queue->napi.weight, | |
108 | skb_queue_len(&queue->tx_queue), | |
109 | timer_pending(&queue->credit_timeout), | |
110 | queue->credit_bytes, | |
111 | queue->credit_usec, | |
112 | queue->remaining_credit, | |
113 | queue->credit_timeout.expires, | |
114 | jiffies); | |
115 | ||
f48da8b1 DV |
116 | dev_queue = netdev_get_tx_queue(queue->vif->dev, queue->id); |
117 | ||
118 | seq_printf(m, "\nRx internal queue: len %u max %u pkts %u %s\n", | |
119 | queue->rx_queue_len, queue->rx_queue_max, | |
120 | skb_queue_len(&queue->rx_queue), | |
121 | netif_tx_queue_stopped(dev_queue) ? "stopped" : "running"); | |
122 | ||
f51de243 ZK |
123 | return 0; |
124 | } | |
125 | ||
126 | #define XENVIF_KICK_STR "kick" | |
5c807005 | 127 | #define BUFFER_SIZE 32 |
f51de243 ZK |
128 | |
129 | static ssize_t | |
130 | xenvif_write_io_ring(struct file *filp, const char __user *buf, size_t count, | |
131 | loff_t *ppos) | |
132 | { | |
133 | struct xenvif_queue *queue = | |
134 | ((struct seq_file *)filp->private_data)->private; | |
135 | int len; | |
5c807005 | 136 | char write[BUFFER_SIZE]; |
f51de243 ZK |
137 | |
138 | /* don't allow partial writes and check the length */ | |
139 | if (*ppos != 0) | |
140 | return 0; | |
5c807005 | 141 | if (count >= sizeof(write)) |
f51de243 ZK |
142 | return -ENOSPC; |
143 | ||
144 | len = simple_write_to_buffer(write, | |
5c807005 | 145 | sizeof(write) - 1, |
f51de243 ZK |
146 | ppos, |
147 | buf, | |
148 | count); | |
149 | if (len < 0) | |
150 | return len; | |
151 | ||
5c807005 WL |
152 | write[len] = '\0'; |
153 | ||
f51de243 ZK |
154 | if (!strncmp(write, XENVIF_KICK_STR, sizeof(XENVIF_KICK_STR) - 1)) |
155 | xenvif_interrupt(0, (void *)queue); | |
156 | else { | |
157 | pr_warn("Unknown command to io_ring_q%d. Available: kick\n", | |
158 | queue->id); | |
159 | count = -EINVAL; | |
160 | } | |
161 | return count; | |
162 | } | |
163 | ||
164 | static int xenvif_dump_open(struct inode *inode, struct file *filp) | |
165 | { | |
166 | int ret; | |
167 | void *queue = NULL; | |
168 | ||
169 | if (inode->i_private) | |
170 | queue = inode->i_private; | |
171 | ret = single_open(filp, xenvif_read_io_ring, queue); | |
172 | filp->f_mode |= FMODE_PWRITE; | |
173 | return ret; | |
174 | } | |
175 | ||
176 | static const struct file_operations xenvif_dbg_io_ring_ops_fops = { | |
177 | .owner = THIS_MODULE, | |
178 | .open = xenvif_dump_open, | |
179 | .read = seq_read, | |
180 | .llseek = seq_lseek, | |
181 | .release = single_release, | |
182 | .write = xenvif_write_io_ring, | |
183 | }; | |
184 | ||
628fa76b | 185 | static void xenvif_debugfs_addif(struct xenvif *vif) |
f51de243 ZK |
186 | { |
187 | struct dentry *pfile; | |
f51de243 ZK |
188 | int i; |
189 | ||
190 | if (IS_ERR_OR_NULL(xen_netback_dbg_root)) | |
191 | return; | |
192 | ||
193 | vif->xenvif_dbg_root = debugfs_create_dir(vif->dev->name, | |
194 | xen_netback_dbg_root); | |
195 | if (!IS_ERR_OR_NULL(vif->xenvif_dbg_root)) { | |
196 | for (i = 0; i < vif->num_queues; ++i) { | |
197 | char filename[sizeof("io_ring_q") + 4]; | |
198 | ||
199 | snprintf(filename, sizeof(filename), "io_ring_q%d", i); | |
200 | pfile = debugfs_create_file(filename, | |
201 | S_IRUSR | S_IWUSR, | |
202 | vif->xenvif_dbg_root, | |
203 | &vif->queues[i], | |
204 | &xenvif_dbg_io_ring_ops_fops); | |
205 | if (IS_ERR_OR_NULL(pfile)) | |
206 | pr_warn("Creation of io_ring file returned %ld!\n", | |
207 | PTR_ERR(pfile)); | |
208 | } | |
209 | } else | |
210 | netdev_warn(vif->dev, | |
211 | "Creation of vif debugfs dir returned %ld!\n", | |
212 | PTR_ERR(vif->xenvif_dbg_root)); | |
213 | } | |
214 | ||
215 | static void xenvif_debugfs_delif(struct xenvif *vif) | |
216 | { | |
217 | if (IS_ERR_OR_NULL(xen_netback_dbg_root)) | |
218 | return; | |
219 | ||
220 | if (!IS_ERR_OR_NULL(vif->xenvif_dbg_root)) | |
221 | debugfs_remove_recursive(vif->xenvif_dbg_root); | |
222 | vif->xenvif_dbg_root = NULL; | |
223 | } | |
224 | #endif /* CONFIG_DEBUG_FS */ | |
225 | ||
f942dc25 IC |
226 | static int netback_remove(struct xenbus_device *dev) |
227 | { | |
228 | struct backend_info *be = dev_get_drvdata(&dev->dev); | |
229 | ||
dc62ccac DV |
230 | set_backend_state(be, XenbusStateClosed); |
231 | ||
f942dc25 IC |
232 | unregister_hotplug_status_watch(be); |
233 | if (be->vif) { | |
234 | kobject_uevent(&dev->dev.kobj, KOBJ_OFFLINE); | |
235 | xenbus_rm(XBT_NIL, dev->nodename, "hotplug-status"); | |
279f438e | 236 | xenvif_free(be->vif); |
f942dc25 IC |
237 | be->vif = NULL; |
238 | } | |
239 | kfree(be); | |
240 | dev_set_drvdata(&dev->dev, NULL); | |
241 | return 0; | |
242 | } | |
243 | ||
244 | ||
245 | /** | |
246 | * Entry point to this code when a new device is created. Allocate the basic | |
247 | * structures and switch to InitWait. | |
248 | */ | |
249 | static int netback_probe(struct xenbus_device *dev, | |
250 | const struct xenbus_device_id *id) | |
251 | { | |
252 | const char *message; | |
253 | struct xenbus_transaction xbt; | |
254 | int err; | |
255 | int sg; | |
256 | struct backend_info *be = kzalloc(sizeof(struct backend_info), | |
257 | GFP_KERNEL); | |
258 | if (!be) { | |
259 | xenbus_dev_fatal(dev, -ENOMEM, | |
260 | "allocating backend structure"); | |
261 | return -ENOMEM; | |
262 | } | |
263 | ||
264 | be->dev = dev; | |
265 | dev_set_drvdata(&dev->dev, be); | |
266 | ||
267 | sg = 1; | |
268 | ||
269 | do { | |
270 | err = xenbus_transaction_start(&xbt); | |
271 | if (err) { | |
272 | xenbus_dev_fatal(dev, err, "starting transaction"); | |
273 | goto fail; | |
274 | } | |
275 | ||
276 | err = xenbus_printf(xbt, dev->nodename, "feature-sg", "%d", sg); | |
277 | if (err) { | |
278 | message = "writing feature-sg"; | |
279 | goto abort_transaction; | |
280 | } | |
281 | ||
282 | err = xenbus_printf(xbt, dev->nodename, "feature-gso-tcpv4", | |
283 | "%d", sg); | |
284 | if (err) { | |
285 | message = "writing feature-gso-tcpv4"; | |
286 | goto abort_transaction; | |
287 | } | |
288 | ||
a9468587 PD |
289 | err = xenbus_printf(xbt, dev->nodename, "feature-gso-tcpv6", |
290 | "%d", sg); | |
291 | if (err) { | |
292 | message = "writing feature-gso-tcpv6"; | |
293 | goto abort_transaction; | |
294 | } | |
295 | ||
2eba61d5 PD |
296 | /* We support partial checksum setup for IPv6 packets */ |
297 | err = xenbus_printf(xbt, dev->nodename, | |
298 | "feature-ipv6-csum-offload", | |
299 | "%d", 1); | |
300 | if (err) { | |
301 | message = "writing feature-ipv6-csum-offload"; | |
302 | goto abort_transaction; | |
303 | } | |
304 | ||
f942dc25 IC |
305 | /* We support rx-copy path. */ |
306 | err = xenbus_printf(xbt, dev->nodename, | |
307 | "feature-rx-copy", "%d", 1); | |
308 | if (err) { | |
309 | message = "writing feature-rx-copy"; | |
310 | goto abort_transaction; | |
311 | } | |
312 | ||
313 | /* | |
314 | * We don't support rx-flip path (except old guests who don't | |
315 | * grok this feature flag). | |
316 | */ | |
317 | err = xenbus_printf(xbt, dev->nodename, | |
318 | "feature-rx-flip", "%d", 0); | |
319 | if (err) { | |
320 | message = "writing feature-rx-flip"; | |
321 | goto abort_transaction; | |
322 | } | |
323 | ||
324 | err = xenbus_transaction_end(xbt, 0); | |
325 | } while (err == -EAGAIN); | |
326 | ||
327 | if (err) { | |
328 | xenbus_dev_fatal(dev, err, "completing transaction"); | |
329 | goto fail; | |
330 | } | |
331 | ||
e1f00a69 WL |
332 | /* |
333 | * Split event channels support, this is optional so it is not | |
334 | * put inside the above loop. | |
335 | */ | |
336 | err = xenbus_printf(XBT_NIL, dev->nodename, | |
337 | "feature-split-event-channels", | |
338 | "%u", separate_tx_rx_irq); | |
339 | if (err) | |
8ef2c3bc | 340 | pr_debug("Error writing feature-split-event-channels\n"); |
e1f00a69 | 341 | |
8d3d53b3 AB |
342 | /* Multi-queue support: This is an optional feature. */ |
343 | err = xenbus_printf(XBT_NIL, dev->nodename, | |
344 | "multi-queue-max-queues", "%u", xenvif_max_queues); | |
345 | if (err) | |
346 | pr_debug("Error writing multi-queue-max-queues\n"); | |
347 | ||
f942dc25 IC |
348 | err = xenbus_switch_state(dev, XenbusStateInitWait); |
349 | if (err) | |
350 | goto fail; | |
351 | ||
ea732dff PD |
352 | be->state = XenbusStateInitWait; |
353 | ||
f942dc25 | 354 | /* This kicks hotplug scripts, so do it immediately. */ |
2dd34339 AK |
355 | err = backend_create_xenvif(be); |
356 | if (err) | |
357 | goto fail; | |
f942dc25 IC |
358 | |
359 | return 0; | |
360 | ||
361 | abort_transaction: | |
362 | xenbus_transaction_end(xbt, 1); | |
363 | xenbus_dev_fatal(dev, err, "%s", message); | |
364 | fail: | |
8ef2c3bc | 365 | pr_debug("failed\n"); |
f942dc25 IC |
366 | netback_remove(dev); |
367 | return err; | |
368 | } | |
369 | ||
370 | ||
371 | /* | |
372 | * Handle the creation of the hotplug script environment. We add the script | |
373 | * and vif variables to the environment, for the benefit of the vif-* hotplug | |
374 | * scripts. | |
375 | */ | |
376 | static int netback_uevent(struct xenbus_device *xdev, | |
377 | struct kobj_uevent_env *env) | |
378 | { | |
379 | struct backend_info *be = dev_get_drvdata(&xdev->dev); | |
380 | char *val; | |
381 | ||
382 | val = xenbus_read(XBT_NIL, xdev->nodename, "script", NULL); | |
383 | if (IS_ERR(val)) { | |
384 | int err = PTR_ERR(val); | |
385 | xenbus_dev_fatal(xdev, err, "reading script"); | |
386 | return err; | |
387 | } else { | |
388 | if (add_uevent_var(env, "script=%s", val)) { | |
389 | kfree(val); | |
390 | return -ENOMEM; | |
391 | } | |
392 | kfree(val); | |
393 | } | |
394 | ||
395 | if (!be || !be->vif) | |
396 | return 0; | |
397 | ||
398 | return add_uevent_var(env, "vif=%s", be->vif->dev->name); | |
399 | } | |
400 | ||
401 | ||
2dd34339 | 402 | static int backend_create_xenvif(struct backend_info *be) |
f942dc25 IC |
403 | { |
404 | int err; | |
405 | long handle; | |
406 | struct xenbus_device *dev = be->dev; | |
407 | ||
408 | if (be->vif != NULL) | |
2dd34339 | 409 | return 0; |
f942dc25 IC |
410 | |
411 | err = xenbus_scanf(XBT_NIL, dev->nodename, "handle", "%li", &handle); | |
412 | if (err != 1) { | |
413 | xenbus_dev_fatal(dev, err, "reading handle"); | |
2dd34339 | 414 | return (err < 0) ? err : -EINVAL; |
f942dc25 IC |
415 | } |
416 | ||
417 | be->vif = xenvif_alloc(&dev->dev, dev->otherend_id, handle); | |
418 | if (IS_ERR(be->vif)) { | |
419 | err = PTR_ERR(be->vif); | |
420 | be->vif = NULL; | |
421 | xenbus_dev_fatal(dev, err, "creating interface"); | |
2dd34339 | 422 | return err; |
f942dc25 IC |
423 | } |
424 | ||
425 | kobject_uevent(&dev->dev.kobj, KOBJ_ONLINE); | |
2dd34339 | 426 | return 0; |
f942dc25 IC |
427 | } |
428 | ||
ea732dff | 429 | static void backend_disconnect(struct backend_info *be) |
f942dc25 | 430 | { |
f51de243 ZK |
431 | if (be->vif) { |
432 | #ifdef CONFIG_DEBUG_FS | |
433 | xenvif_debugfs_delif(be->vif); | |
434 | #endif /* CONFIG_DEBUG_FS */ | |
279f438e | 435 | xenvif_disconnect(be->vif); |
f51de243 | 436 | } |
279f438e PD |
437 | } |
438 | ||
ea732dff | 439 | static void backend_connect(struct backend_info *be) |
279f438e | 440 | { |
ea732dff PD |
441 | if (be->vif) |
442 | connect(be); | |
443 | } | |
279f438e | 444 | |
ea732dff PD |
445 | static inline void backend_switch_state(struct backend_info *be, |
446 | enum xenbus_state state) | |
447 | { | |
448 | struct xenbus_device *dev = be->dev; | |
449 | ||
450 | pr_debug("%s -> %s\n", dev->nodename, xenbus_strstate(state)); | |
451 | be->state = state; | |
452 | ||
453 | /* If we are waiting for a hotplug script then defer the | |
454 | * actual xenbus state change. | |
455 | */ | |
456 | if (!be->have_hotplug_status_watch) | |
457 | xenbus_switch_state(dev, state); | |
458 | } | |
459 | ||
460 | /* Handle backend state transitions: | |
461 | * | |
462 | * The backend state starts in InitWait and the following transitions are | |
463 | * allowed. | |
464 | * | |
465 | * InitWait -> Connected | |
466 | * | |
467 | * ^ \ | | |
468 | * | \ | | |
469 | * | \ | | |
470 | * | \ | | |
471 | * | \ | | |
472 | * | \ | | |
473 | * | V V | |
474 | * | |
475 | * Closed <-> Closing | |
476 | * | |
477 | * The state argument specifies the eventual state of the backend and the | |
478 | * function transitions to that state via the shortest path. | |
479 | */ | |
480 | static void set_backend_state(struct backend_info *be, | |
481 | enum xenbus_state state) | |
482 | { | |
483 | while (be->state != state) { | |
484 | switch (be->state) { | |
485 | case XenbusStateClosed: | |
486 | switch (state) { | |
487 | case XenbusStateInitWait: | |
488 | case XenbusStateConnected: | |
489 | pr_info("%s: prepare for reconnect\n", | |
490 | be->dev->nodename); | |
491 | backend_switch_state(be, XenbusStateInitWait); | |
492 | break; | |
493 | case XenbusStateClosing: | |
494 | backend_switch_state(be, XenbusStateClosing); | |
495 | break; | |
496 | default: | |
497 | BUG(); | |
498 | } | |
499 | break; | |
500 | case XenbusStateInitWait: | |
501 | switch (state) { | |
502 | case XenbusStateConnected: | |
503 | backend_connect(be); | |
504 | backend_switch_state(be, XenbusStateConnected); | |
505 | break; | |
506 | case XenbusStateClosing: | |
507 | case XenbusStateClosed: | |
508 | backend_switch_state(be, XenbusStateClosing); | |
509 | break; | |
510 | default: | |
511 | BUG(); | |
512 | } | |
513 | break; | |
514 | case XenbusStateConnected: | |
515 | switch (state) { | |
516 | case XenbusStateInitWait: | |
517 | case XenbusStateClosing: | |
518 | case XenbusStateClosed: | |
519 | backend_disconnect(be); | |
520 | backend_switch_state(be, XenbusStateClosing); | |
521 | break; | |
522 | default: | |
523 | BUG(); | |
524 | } | |
525 | break; | |
526 | case XenbusStateClosing: | |
527 | switch (state) { | |
528 | case XenbusStateInitWait: | |
529 | case XenbusStateConnected: | |
530 | case XenbusStateClosed: | |
531 | backend_switch_state(be, XenbusStateClosed); | |
532 | break; | |
533 | default: | |
534 | BUG(); | |
535 | } | |
536 | break; | |
537 | default: | |
538 | BUG(); | |
539 | } | |
f942dc25 IC |
540 | } |
541 | } | |
542 | ||
543 | /** | |
544 | * Callback received when the frontend's state changes. | |
545 | */ | |
546 | static void frontend_changed(struct xenbus_device *dev, | |
547 | enum xenbus_state frontend_state) | |
548 | { | |
549 | struct backend_info *be = dev_get_drvdata(&dev->dev); | |
550 | ||
ea732dff | 551 | pr_debug("%s -> %s\n", dev->otherend, xenbus_strstate(frontend_state)); |
f942dc25 IC |
552 | |
553 | be->frontend_state = frontend_state; | |
554 | ||
555 | switch (frontend_state) { | |
556 | case XenbusStateInitialising: | |
ea732dff | 557 | set_backend_state(be, XenbusStateInitWait); |
f942dc25 IC |
558 | break; |
559 | ||
560 | case XenbusStateInitialised: | |
561 | break; | |
562 | ||
563 | case XenbusStateConnected: | |
ea732dff | 564 | set_backend_state(be, XenbusStateConnected); |
f942dc25 IC |
565 | break; |
566 | ||
567 | case XenbusStateClosing: | |
ea732dff | 568 | set_backend_state(be, XenbusStateClosing); |
f942dc25 IC |
569 | break; |
570 | ||
571 | case XenbusStateClosed: | |
ea732dff | 572 | set_backend_state(be, XenbusStateClosed); |
f942dc25 IC |
573 | if (xenbus_dev_is_online(dev)) |
574 | break; | |
575 | /* fall through if not online */ | |
576 | case XenbusStateUnknown: | |
ea732dff | 577 | set_backend_state(be, XenbusStateClosed); |
f942dc25 IC |
578 | device_unregister(&dev->dev); |
579 | break; | |
580 | ||
581 | default: | |
582 | xenbus_dev_fatal(dev, -EINVAL, "saw state %d at frontend", | |
583 | frontend_state); | |
584 | break; | |
585 | } | |
586 | } | |
587 | ||
588 | ||
589 | static void xen_net_read_rate(struct xenbus_device *dev, | |
590 | unsigned long *bytes, unsigned long *usec) | |
591 | { | |
592 | char *s, *e; | |
593 | unsigned long b, u; | |
594 | char *ratestr; | |
595 | ||
596 | /* Default to unlimited bandwidth. */ | |
597 | *bytes = ~0UL; | |
598 | *usec = 0; | |
599 | ||
600 | ratestr = xenbus_read(XBT_NIL, dev->nodename, "rate", NULL); | |
601 | if (IS_ERR(ratestr)) | |
602 | return; | |
603 | ||
604 | s = ratestr; | |
605 | b = simple_strtoul(s, &e, 10); | |
606 | if ((s == e) || (*e != ',')) | |
607 | goto fail; | |
608 | ||
609 | s = e + 1; | |
610 | u = simple_strtoul(s, &e, 10); | |
611 | if ((s == e) || (*e != '\0')) | |
612 | goto fail; | |
613 | ||
614 | *bytes = b; | |
615 | *usec = u; | |
616 | ||
617 | kfree(ratestr); | |
618 | return; | |
619 | ||
620 | fail: | |
621 | pr_warn("Failed to parse network rate limit. Traffic unlimited.\n"); | |
622 | kfree(ratestr); | |
623 | } | |
624 | ||
625 | static int xen_net_read_mac(struct xenbus_device *dev, u8 mac[]) | |
626 | { | |
627 | char *s, *e, *macstr; | |
628 | int i; | |
629 | ||
630 | macstr = s = xenbus_read(XBT_NIL, dev->nodename, "mac", NULL); | |
631 | if (IS_ERR(macstr)) | |
632 | return PTR_ERR(macstr); | |
633 | ||
634 | for (i = 0; i < ETH_ALEN; i++) { | |
635 | mac[i] = simple_strtoul(s, &e, 16); | |
636 | if ((s == e) || (*e != ((i == ETH_ALEN-1) ? '\0' : ':'))) { | |
637 | kfree(macstr); | |
638 | return -ENOENT; | |
639 | } | |
640 | s = e+1; | |
641 | } | |
642 | ||
643 | kfree(macstr); | |
644 | return 0; | |
645 | } | |
646 | ||
647 | static void unregister_hotplug_status_watch(struct backend_info *be) | |
648 | { | |
649 | if (be->have_hotplug_status_watch) { | |
650 | unregister_xenbus_watch(&be->hotplug_status_watch); | |
651 | kfree(be->hotplug_status_watch.node); | |
652 | } | |
653 | be->have_hotplug_status_watch = 0; | |
654 | } | |
655 | ||
656 | static void hotplug_status_changed(struct xenbus_watch *watch, | |
657 | const char **vec, | |
658 | unsigned int vec_size) | |
659 | { | |
660 | struct backend_info *be = container_of(watch, | |
661 | struct backend_info, | |
662 | hotplug_status_watch); | |
663 | char *str; | |
664 | unsigned int len; | |
665 | ||
666 | str = xenbus_read(XBT_NIL, be->dev->nodename, "hotplug-status", &len); | |
667 | if (IS_ERR(str)) | |
668 | return; | |
669 | if (len == sizeof("connected")-1 && !memcmp(str, "connected", len)) { | |
ea732dff PD |
670 | /* Complete any pending state change */ |
671 | xenbus_switch_state(be->dev, be->state); | |
672 | ||
f942dc25 IC |
673 | /* Not interested in this watch anymore. */ |
674 | unregister_hotplug_status_watch(be); | |
675 | } | |
676 | kfree(str); | |
677 | } | |
678 | ||
679 | static void connect(struct backend_info *be) | |
680 | { | |
681 | int err; | |
682 | struct xenbus_device *dev = be->dev; | |
e9ce7cb6 WL |
683 | unsigned long credit_bytes, credit_usec; |
684 | unsigned int queue_index; | |
8d3d53b3 | 685 | unsigned int requested_num_queues; |
e9ce7cb6 | 686 | struct xenvif_queue *queue; |
f942dc25 | 687 | |
8d3d53b3 AB |
688 | /* Check whether the frontend requested multiple queues |
689 | * and read the number requested. | |
690 | */ | |
691 | err = xenbus_scanf(XBT_NIL, dev->otherend, | |
692 | "multi-queue-num-queues", | |
693 | "%u", &requested_num_queues); | |
694 | if (err < 0) { | |
695 | requested_num_queues = 1; /* Fall back to single queue */ | |
696 | } else if (requested_num_queues > xenvif_max_queues) { | |
697 | /* buggy or malicious guest */ | |
698 | xenbus_dev_fatal(dev, err, | |
699 | "guest requested %u queues, exceeding the maximum of %u.", | |
700 | requested_num_queues, xenvif_max_queues); | |
701 | return; | |
702 | } | |
703 | ||
f942dc25 IC |
704 | err = xen_net_read_mac(dev, be->vif->fe_dev_addr); |
705 | if (err) { | |
706 | xenbus_dev_fatal(dev, err, "parsing %s/mac", dev->nodename); | |
707 | return; | |
708 | } | |
709 | ||
e9ce7cb6 WL |
710 | xen_net_read_rate(dev, &credit_bytes, &credit_usec); |
711 | read_xenbus_vif_flags(be); | |
712 | ||
8d3d53b3 | 713 | /* Use the number of queues requested by the frontend */ |
e9ce7cb6 WL |
714 | be->vif->queues = vzalloc(requested_num_queues * |
715 | sizeof(struct xenvif_queue)); | |
f7b50c4e | 716 | be->vif->num_queues = requested_num_queues; |
ecf08d2d | 717 | be->vif->stalled_queues = requested_num_queues; |
e9ce7cb6 WL |
718 | |
719 | for (queue_index = 0; queue_index < requested_num_queues; ++queue_index) { | |
720 | queue = &be->vif->queues[queue_index]; | |
721 | queue->vif = be->vif; | |
722 | queue->id = queue_index; | |
723 | snprintf(queue->name, sizeof(queue->name), "%s-q%u", | |
724 | be->vif->dev->name, queue->id); | |
725 | ||
726 | err = xenvif_init_queue(queue); | |
8d3d53b3 AB |
727 | if (err) { |
728 | /* xenvif_init_queue() cleans up after itself on | |
729 | * failure, but we need to clean up any previously | |
730 | * initialised queues. Set num_queues to i so that | |
731 | * earlier queues can be destroyed using the regular | |
732 | * disconnect logic. | |
733 | */ | |
f7b50c4e | 734 | be->vif->num_queues = queue_index; |
e9ce7cb6 | 735 | goto err; |
8d3d53b3 | 736 | } |
e9ce7cb6 WL |
737 | |
738 | queue->remaining_credit = credit_bytes; | |
739 | ||
740 | err = connect_rings(be, queue); | |
8d3d53b3 AB |
741 | if (err) { |
742 | /* connect_rings() cleans up after itself on failure, | |
743 | * but we need to clean up after xenvif_init_queue() here, | |
744 | * and also clean up any previously initialised queues. | |
745 | */ | |
746 | xenvif_deinit_queue(queue); | |
f7b50c4e | 747 | be->vif->num_queues = queue_index; |
e9ce7cb6 | 748 | goto err; |
8d3d53b3 | 749 | } |
628fa76b WL |
750 | } |
751 | ||
f51de243 | 752 | #ifdef CONFIG_DEBUG_FS |
628fa76b | 753 | xenvif_debugfs_addif(be->vif); |
f51de243 | 754 | #endif /* CONFIG_DEBUG_FS */ |
e9ce7cb6 | 755 | |
f7b50c4e WL |
756 | /* Initialisation completed, tell core driver the number of |
757 | * active queues. | |
758 | */ | |
759 | rtnl_lock(); | |
760 | netif_set_real_num_tx_queues(be->vif->dev, requested_num_queues); | |
761 | netif_set_real_num_rx_queues(be->vif->dev, requested_num_queues); | |
762 | rtnl_unlock(); | |
763 | ||
e9ce7cb6 | 764 | xenvif_carrier_on(be->vif); |
f942dc25 IC |
765 | |
766 | unregister_hotplug_status_watch(be); | |
767 | err = xenbus_watch_pathfmt(dev, &be->hotplug_status_watch, | |
768 | hotplug_status_changed, | |
769 | "%s/%s", dev->nodename, "hotplug-status"); | |
ea732dff | 770 | if (!err) |
f942dc25 | 771 | be->have_hotplug_status_watch = 1; |
f942dc25 | 772 | |
e9ce7cb6 WL |
773 | netif_tx_wake_all_queues(be->vif->dev); |
774 | ||
775 | return; | |
776 | ||
777 | err: | |
f7b50c4e | 778 | if (be->vif->num_queues > 0) |
8d3d53b3 | 779 | xenvif_disconnect(be->vif); /* Clean up existing queues */ |
e9ce7cb6 WL |
780 | vfree(be->vif->queues); |
781 | be->vif->queues = NULL; | |
f7b50c4e | 782 | be->vif->num_queues = 0; |
e9ce7cb6 | 783 | return; |
f942dc25 IC |
784 | } |
785 | ||
786 | ||
e9ce7cb6 | 787 | static int connect_rings(struct backend_info *be, struct xenvif_queue *queue) |
f942dc25 | 788 | { |
f942dc25 | 789 | struct xenbus_device *dev = be->dev; |
f7b50c4e | 790 | unsigned int num_queues = queue->vif->num_queues; |
f942dc25 | 791 | unsigned long tx_ring_ref, rx_ring_ref; |
e9ce7cb6 | 792 | unsigned int tx_evtchn, rx_evtchn; |
f942dc25 | 793 | int err; |
8d3d53b3 AB |
794 | char *xspath; |
795 | size_t xspathsize; | |
796 | const size_t xenstore_path_ext_size = 11; /* sufficient for "/queue-NNN" */ | |
797 | ||
798 | /* If the frontend requested 1 queue, or we have fallen back | |
799 | * to single queue due to lack of frontend support for multi- | |
800 | * queue, expect the remaining XenStore keys in the toplevel | |
801 | * directory. Otherwise, expect them in a subdirectory called | |
802 | * queue-N. | |
803 | */ | |
804 | if (num_queues == 1) { | |
805 | xspath = kzalloc(strlen(dev->otherend) + 1, GFP_KERNEL); | |
806 | if (!xspath) { | |
807 | xenbus_dev_fatal(dev, -ENOMEM, | |
808 | "reading ring references"); | |
809 | return -ENOMEM; | |
810 | } | |
811 | strcpy(xspath, dev->otherend); | |
812 | } else { | |
813 | xspathsize = strlen(dev->otherend) + xenstore_path_ext_size; | |
814 | xspath = kzalloc(xspathsize, GFP_KERNEL); | |
815 | if (!xspath) { | |
816 | xenbus_dev_fatal(dev, -ENOMEM, | |
817 | "reading ring references"); | |
818 | return -ENOMEM; | |
819 | } | |
820 | snprintf(xspath, xspathsize, "%s/queue-%u", dev->otherend, | |
821 | queue->id); | |
822 | } | |
f942dc25 | 823 | |
8d3d53b3 | 824 | err = xenbus_gather(XBT_NIL, xspath, |
f942dc25 | 825 | "tx-ring-ref", "%lu", &tx_ring_ref, |
e1f00a69 | 826 | "rx-ring-ref", "%lu", &rx_ring_ref, NULL); |
f942dc25 IC |
827 | if (err) { |
828 | xenbus_dev_fatal(dev, err, | |
e1f00a69 | 829 | "reading %s/ring-ref", |
8d3d53b3 AB |
830 | xspath); |
831 | goto err; | |
f942dc25 IC |
832 | } |
833 | ||
e1f00a69 | 834 | /* Try split event channels first, then single event channel. */ |
8d3d53b3 | 835 | err = xenbus_gather(XBT_NIL, xspath, |
e1f00a69 WL |
836 | "event-channel-tx", "%u", &tx_evtchn, |
837 | "event-channel-rx", "%u", &rx_evtchn, NULL); | |
838 | if (err < 0) { | |
8d3d53b3 | 839 | err = xenbus_scanf(XBT_NIL, xspath, |
e1f00a69 WL |
840 | "event-channel", "%u", &tx_evtchn); |
841 | if (err < 0) { | |
842 | xenbus_dev_fatal(dev, err, | |
843 | "reading %s/event-channel(-tx/rx)", | |
8d3d53b3 AB |
844 | xspath); |
845 | goto err; | |
e1f00a69 WL |
846 | } |
847 | rx_evtchn = tx_evtchn; | |
848 | } | |
849 | ||
e9ce7cb6 WL |
850 | /* Map the shared frame, irq etc. */ |
851 | err = xenvif_connect(queue, tx_ring_ref, rx_ring_ref, | |
852 | tx_evtchn, rx_evtchn); | |
853 | if (err) { | |
854 | xenbus_dev_fatal(dev, err, | |
855 | "mapping shared-frames %lu/%lu port tx %u rx %u", | |
856 | tx_ring_ref, rx_ring_ref, | |
857 | tx_evtchn, rx_evtchn); | |
8d3d53b3 | 858 | goto err; |
e9ce7cb6 WL |
859 | } |
860 | ||
8d3d53b3 AB |
861 | err = 0; |
862 | err: /* Regular return falls through with err == 0 */ | |
863 | kfree(xspath); | |
864 | return err; | |
e9ce7cb6 WL |
865 | } |
866 | ||
867 | static int read_xenbus_vif_flags(struct backend_info *be) | |
868 | { | |
869 | struct xenvif *vif = be->vif; | |
870 | struct xenbus_device *dev = be->dev; | |
871 | unsigned int rx_copy; | |
872 | int err, val; | |
873 | ||
f942dc25 IC |
874 | err = xenbus_scanf(XBT_NIL, dev->otherend, "request-rx-copy", "%u", |
875 | &rx_copy); | |
876 | if (err == -ENOENT) { | |
877 | err = 0; | |
878 | rx_copy = 0; | |
879 | } | |
880 | if (err < 0) { | |
881 | xenbus_dev_fatal(dev, err, "reading %s/request-rx-copy", | |
882 | dev->otherend); | |
883 | return err; | |
884 | } | |
885 | if (!rx_copy) | |
886 | return -EOPNOTSUPP; | |
887 | ||
bc96f648 DV |
888 | if (xenbus_scanf(XBT_NIL, dev->otherend, |
889 | "feature-rx-notify", "%d", &val) < 0 || val == 0) { | |
890 | xenbus_dev_fatal(dev, -EINVAL, "feature-rx-notify is mandatory"); | |
891 | return -EINVAL; | |
f942dc25 IC |
892 | } |
893 | ||
894 | if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-sg", | |
895 | "%d", &val) < 0) | |
896 | val = 0; | |
897 | vif->can_sg = !!val; | |
898 | ||
82cada22 PD |
899 | vif->gso_mask = 0; |
900 | vif->gso_prefix_mask = 0; | |
901 | ||
f942dc25 IC |
902 | if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-gso-tcpv4", |
903 | "%d", &val) < 0) | |
904 | val = 0; | |
82cada22 PD |
905 | if (val) |
906 | vif->gso_mask |= GSO_BIT(TCPV4); | |
f942dc25 IC |
907 | |
908 | if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-gso-tcpv4-prefix", | |
909 | "%d", &val) < 0) | |
910 | val = 0; | |
82cada22 PD |
911 | if (val) |
912 | vif->gso_prefix_mask |= GSO_BIT(TCPV4); | |
913 | ||
914 | if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-gso-tcpv6", | |
915 | "%d", &val) < 0) | |
916 | val = 0; | |
917 | if (val) | |
918 | vif->gso_mask |= GSO_BIT(TCPV6); | |
919 | ||
920 | if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-gso-tcpv6-prefix", | |
921 | "%d", &val) < 0) | |
922 | val = 0; | |
923 | if (val) | |
924 | vif->gso_prefix_mask |= GSO_BIT(TCPV6); | |
925 | ||
926 | if (vif->gso_mask & vif->gso_prefix_mask) { | |
927 | xenbus_dev_fatal(dev, err, | |
928 | "%s: gso and gso prefix flags are not " | |
929 | "mutually exclusive", | |
930 | dev->otherend); | |
931 | return -EOPNOTSUPP; | |
932 | } | |
f942dc25 IC |
933 | |
934 | if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-no-csum-offload", | |
935 | "%d", &val) < 0) | |
936 | val = 0; | |
146c8a77 PD |
937 | vif->ip_csum = !val; |
938 | ||
939 | if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-ipv6-csum-offload", | |
940 | "%d", &val) < 0) | |
941 | val = 0; | |
942 | vif->ipv6_csum = !!val; | |
f942dc25 | 943 | |
f942dc25 IC |
944 | return 0; |
945 | } | |
946 | ||
f942dc25 IC |
947 | static const struct xenbus_device_id netback_ids[] = { |
948 | { "vif" }, | |
949 | { "" } | |
950 | }; | |
951 | ||
95afae48 DV |
952 | static struct xenbus_driver netback_driver = { |
953 | .ids = netback_ids, | |
f942dc25 IC |
954 | .probe = netback_probe, |
955 | .remove = netback_remove, | |
956 | .uevent = netback_uevent, | |
957 | .otherend_changed = frontend_changed, | |
95afae48 | 958 | }; |
f942dc25 IC |
959 | |
960 | int xenvif_xenbus_init(void) | |
961 | { | |
73db144b | 962 | return xenbus_register_backend(&netback_driver); |
f942dc25 | 963 | } |
b103f358 WL |
964 | |
965 | void xenvif_xenbus_fini(void) | |
966 | { | |
967 | return xenbus_unregister_driver(&netback_driver); | |
968 | } |