Commit | Line | Data |
---|---|---|
72e59c30 SS |
1 | /* |
2 | * (c) 2017 Stefano Stabellini <stefano@aporeto.com> | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or modify | |
5 | * it under the terms of the GNU General Public License as published by | |
6 | * the Free Software Foundation; either version 2 of the License, or | |
7 | * (at your option) any later version. | |
8 | * | |
9 | * This program is distributed in the hope that it will be useful, | |
10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
12 | * GNU General Public License for more details. | |
13 | */ | |
14 | ||
fb029875 | 15 | #include <linux/inet.h> |
72e59c30 SS |
16 | #include <linux/kthread.h> |
17 | #include <linux/list.h> | |
18 | #include <linux/radix-tree.h> | |
19 | #include <linux/module.h> | |
20 | #include <linux/semaphore.h> | |
21 | #include <linux/wait.h> | |
fb029875 SS |
22 | #include <net/sock.h> |
23 | #include <net/inet_common.h> | |
24 | #include <net/inet_connection_sock.h> | |
25 | #include <net/request_sock.h> | |
72e59c30 SS |
26 | |
27 | #include <xen/events.h> | |
28 | #include <xen/grant_table.h> | |
29 | #include <xen/xen.h> | |
30 | #include <xen/xenbus.h> | |
31 | #include <xen/interface/io/pvcalls.h> | |
32 | ||
0a9c75c2 SS |
33 | #define PVCALLS_VERSIONS "1" |
34 | #define MAX_RING_ORDER XENBUS_MAX_RING_GRANT_ORDER | |
35 | ||
9be07334 SS |
36 | struct pvcalls_back_global { |
37 | struct list_head frontends; | |
38 | struct semaphore frontends_lock; | |
39 | } pvcalls_back_global; | |
40 | ||
d0e4d560 SS |
41 | /* |
42 | * Per-frontend data structure. It contains pointers to the command | |
43 | * ring, its event channel, a list of active sockets and a tree of | |
44 | * passive sockets. | |
45 | */ | |
46 | struct pvcalls_fedata { | |
47 | struct list_head list; | |
48 | struct xenbus_device *dev; | |
49 | struct xen_pvcalls_sring *sring; | |
50 | struct xen_pvcalls_back_ring ring; | |
51 | int irq; | |
52 | struct list_head socket_mappings; | |
53 | struct radix_tree_root socketpass_mappings; | |
54 | struct semaphore socket_lock; | |
55 | }; | |
56 | ||
5db4d286 SS |
57 | struct pvcalls_ioworker { |
58 | struct work_struct register_work; | |
59 | struct workqueue_struct *wq; | |
60 | }; | |
61 | ||
62 | struct sock_mapping { | |
63 | struct list_head list; | |
64 | struct pvcalls_fedata *fedata; | |
6f474e71 | 65 | struct sockpass_mapping *sockpass; |
5db4d286 SS |
66 | struct socket *sock; |
67 | uint64_t id; | |
68 | grant_ref_t ref; | |
69 | struct pvcalls_data_intf *ring; | |
70 | void *bytes; | |
71 | struct pvcalls_data data; | |
72 | uint32_t ring_order; | |
73 | int irq; | |
74 | atomic_t read; | |
75 | atomic_t write; | |
76 | atomic_t io; | |
77 | atomic_t release; | |
78 | void (*saved_data_ready)(struct sock *sk); | |
79 | struct pvcalls_ioworker ioworker; | |
80 | }; | |
81 | ||
331a63e6 SS |
82 | struct sockpass_mapping { |
83 | struct list_head list; | |
84 | struct pvcalls_fedata *fedata; | |
85 | struct socket *sock; | |
86 | uint64_t id; | |
87 | struct xen_pvcalls_request reqcopy; | |
88 | spinlock_t copy_lock; | |
89 | struct workqueue_struct *wq; | |
90 | struct work_struct register_work; | |
91 | void (*saved_data_ready)(struct sock *sk); | |
92 | }; | |
93 | ||
5db4d286 SS |
94 | static irqreturn_t pvcalls_back_conn_event(int irq, void *sock_map); |
95 | static int pvcalls_back_release_active(struct xenbus_device *dev, | |
96 | struct pvcalls_fedata *fedata, | |
97 | struct sock_mapping *map); | |
98 | ||
5d520d85 SS |
99 | static void pvcalls_conn_back_read(void *opaque) |
100 | { | |
b3f9f773 SS |
101 | struct sock_mapping *map = (struct sock_mapping *)opaque; |
102 | struct msghdr msg; | |
103 | struct kvec vec[2]; | |
104 | RING_IDX cons, prod, size, wanted, array_size, masked_prod, masked_cons; | |
105 | int32_t error; | |
106 | struct pvcalls_data_intf *intf = map->ring; | |
107 | struct pvcalls_data *data = &map->data; | |
108 | unsigned long flags; | |
109 | int ret; | |
110 | ||
111 | array_size = XEN_FLEX_RING_SIZE(map->ring_order); | |
112 | cons = intf->in_cons; | |
113 | prod = intf->in_prod; | |
114 | error = intf->in_error; | |
115 | /* read the indexes first, then deal with the data */ | |
116 | virt_mb(); | |
117 | ||
118 | if (error) | |
119 | return; | |
120 | ||
121 | size = pvcalls_queued(prod, cons, array_size); | |
122 | if (size >= array_size) | |
123 | return; | |
124 | spin_lock_irqsave(&map->sock->sk->sk_receive_queue.lock, flags); | |
125 | if (skb_queue_empty(&map->sock->sk->sk_receive_queue)) { | |
126 | atomic_set(&map->read, 0); | |
127 | spin_unlock_irqrestore(&map->sock->sk->sk_receive_queue.lock, | |
128 | flags); | |
129 | return; | |
130 | } | |
131 | spin_unlock_irqrestore(&map->sock->sk->sk_receive_queue.lock, flags); | |
132 | wanted = array_size - size; | |
133 | masked_prod = pvcalls_mask(prod, array_size); | |
134 | masked_cons = pvcalls_mask(cons, array_size); | |
135 | ||
136 | memset(&msg, 0, sizeof(msg)); | |
b3f9f773 SS |
137 | if (masked_prod < masked_cons) { |
138 | vec[0].iov_base = data->in + masked_prod; | |
139 | vec[0].iov_len = wanted; | |
83683dc6 | 140 | iov_iter_kvec(&msg.msg_iter, ITER_KVEC|WRITE, vec, 1, wanted); |
b3f9f773 SS |
141 | } else { |
142 | vec[0].iov_base = data->in + masked_prod; | |
143 | vec[0].iov_len = array_size - masked_prod; | |
144 | vec[1].iov_base = data->in; | |
145 | vec[1].iov_len = wanted - vec[0].iov_len; | |
83683dc6 | 146 | iov_iter_kvec(&msg.msg_iter, ITER_KVEC|WRITE, vec, 2, wanted); |
b3f9f773 SS |
147 | } |
148 | ||
149 | atomic_set(&map->read, 0); | |
150 | ret = inet_recvmsg(map->sock, &msg, wanted, MSG_DONTWAIT); | |
151 | WARN_ON(ret > wanted); | |
152 | if (ret == -EAGAIN) /* shouldn't happen */ | |
153 | return; | |
154 | if (!ret) | |
155 | ret = -ENOTCONN; | |
156 | spin_lock_irqsave(&map->sock->sk->sk_receive_queue.lock, flags); | |
157 | if (ret > 0 && !skb_queue_empty(&map->sock->sk->sk_receive_queue)) | |
158 | atomic_inc(&map->read); | |
159 | spin_unlock_irqrestore(&map->sock->sk->sk_receive_queue.lock, flags); | |
160 | ||
161 | /* write the data, then modify the indexes */ | |
162 | virt_wmb(); | |
163 | if (ret < 0) | |
164 | intf->in_error = ret; | |
165 | else | |
166 | intf->in_prod = prod + ret; | |
167 | /* update the indexes, then notify the other end */ | |
168 | virt_wmb(); | |
169 | notify_remote_via_irq(map->irq); | |
170 | ||
171 | return; | |
5d520d85 SS |
172 | } |
173 | ||
174 | static void pvcalls_conn_back_write(struct sock_mapping *map) | |
175 | { | |
5ad9918f SS |
176 | struct pvcalls_data_intf *intf = map->ring; |
177 | struct pvcalls_data *data = &map->data; | |
178 | struct msghdr msg; | |
179 | struct kvec vec[2]; | |
180 | RING_IDX cons, prod, size, array_size; | |
181 | int ret; | |
182 | ||
183 | cons = intf->out_cons; | |
184 | prod = intf->out_prod; | |
185 | /* read the indexes before dealing with the data */ | |
186 | virt_mb(); | |
187 | ||
188 | array_size = XEN_FLEX_RING_SIZE(map->ring_order); | |
189 | size = pvcalls_queued(prod, cons, array_size); | |
190 | if (size == 0) | |
191 | return; | |
192 | ||
193 | memset(&msg, 0, sizeof(msg)); | |
194 | msg.msg_flags |= MSG_DONTWAIT; | |
5ad9918f SS |
195 | if (pvcalls_mask(prod, array_size) > pvcalls_mask(cons, array_size)) { |
196 | vec[0].iov_base = data->out + pvcalls_mask(cons, array_size); | |
197 | vec[0].iov_len = size; | |
83683dc6 | 198 | iov_iter_kvec(&msg.msg_iter, ITER_KVEC|READ, vec, 1, size); |
5ad9918f SS |
199 | } else { |
200 | vec[0].iov_base = data->out + pvcalls_mask(cons, array_size); | |
201 | vec[0].iov_len = array_size - pvcalls_mask(cons, array_size); | |
202 | vec[1].iov_base = data->out; | |
203 | vec[1].iov_len = size - vec[0].iov_len; | |
83683dc6 | 204 | iov_iter_kvec(&msg.msg_iter, ITER_KVEC|READ, vec, 2, size); |
5ad9918f SS |
205 | } |
206 | ||
207 | atomic_set(&map->write, 0); | |
208 | ret = inet_sendmsg(map->sock, &msg, size); | |
209 | if (ret == -EAGAIN || (ret >= 0 && ret < size)) { | |
210 | atomic_inc(&map->write); | |
211 | atomic_inc(&map->io); | |
212 | } | |
213 | if (ret == -EAGAIN) | |
214 | return; | |
215 | ||
216 | /* write the data, then update the indexes */ | |
217 | virt_wmb(); | |
218 | if (ret < 0) { | |
219 | intf->out_error = ret; | |
220 | } else { | |
221 | intf->out_error = 0; | |
222 | intf->out_cons = cons + ret; | |
223 | prod = intf->out_prod; | |
224 | } | |
225 | /* update the indexes, then notify the other end */ | |
226 | virt_wmb(); | |
227 | if (prod != cons + ret) | |
228 | atomic_inc(&map->write); | |
229 | notify_remote_via_irq(map->irq); | |
5d520d85 SS |
230 | } |
231 | ||
5db4d286 SS |
232 | static void pvcalls_back_ioworker(struct work_struct *work) |
233 | { | |
5d520d85 SS |
234 | struct pvcalls_ioworker *ioworker = container_of(work, |
235 | struct pvcalls_ioworker, register_work); | |
236 | struct sock_mapping *map = container_of(ioworker, struct sock_mapping, | |
237 | ioworker); | |
238 | ||
239 | while (atomic_read(&map->io) > 0) { | |
240 | if (atomic_read(&map->release) > 0) { | |
241 | atomic_set(&map->release, 0); | |
242 | return; | |
243 | } | |
244 | ||
245 | if (atomic_read(&map->read) > 0) | |
246 | pvcalls_conn_back_read(map); | |
247 | if (atomic_read(&map->write) > 0) | |
248 | pvcalls_conn_back_write(map); | |
249 | ||
250 | atomic_dec(&map->io); | |
251 | } | |
5db4d286 SS |
252 | } |
253 | ||
b1efa693 SS |
254 | static int pvcalls_back_socket(struct xenbus_device *dev, |
255 | struct xen_pvcalls_request *req) | |
256 | { | |
fb029875 SS |
257 | struct pvcalls_fedata *fedata; |
258 | int ret; | |
259 | struct xen_pvcalls_response *rsp; | |
260 | ||
261 | fedata = dev_get_drvdata(&dev->dev); | |
262 | ||
263 | if (req->u.socket.domain != AF_INET || | |
264 | req->u.socket.type != SOCK_STREAM || | |
265 | (req->u.socket.protocol != IPPROTO_IP && | |
266 | req->u.socket.protocol != AF_INET)) | |
267 | ret = -EAFNOSUPPORT; | |
268 | else | |
269 | ret = 0; | |
270 | ||
271 | /* leave the actual socket allocation for later */ | |
272 | ||
273 | rsp = RING_GET_RESPONSE(&fedata->ring, fedata->ring.rsp_prod_pvt++); | |
274 | rsp->req_id = req->req_id; | |
275 | rsp->cmd = req->cmd; | |
276 | rsp->u.socket.id = req->u.socket.id; | |
277 | rsp->ret = ret; | |
278 | ||
b1efa693 SS |
279 | return 0; |
280 | } | |
281 | ||
5db4d286 SS |
282 | static void pvcalls_sk_state_change(struct sock *sock) |
283 | { | |
284 | struct sock_mapping *map = sock->sk_user_data; | |
285 | struct pvcalls_data_intf *intf; | |
286 | ||
287 | if (map == NULL) | |
288 | return; | |
289 | ||
290 | intf = map->ring; | |
291 | intf->in_error = -ENOTCONN; | |
292 | notify_remote_via_irq(map->irq); | |
293 | } | |
294 | ||
295 | static void pvcalls_sk_data_ready(struct sock *sock) | |
296 | { | |
b3f9f773 SS |
297 | struct sock_mapping *map = sock->sk_user_data; |
298 | struct pvcalls_ioworker *iow; | |
299 | ||
300 | if (map == NULL) | |
301 | return; | |
302 | ||
303 | iow = &map->ioworker; | |
304 | atomic_inc(&map->read); | |
305 | atomic_inc(&map->io); | |
306 | queue_work(iow->wq, &iow->register_work); | |
5db4d286 SS |
307 | } |
308 | ||
309 | static struct sock_mapping *pvcalls_new_active_socket( | |
310 | struct pvcalls_fedata *fedata, | |
311 | uint64_t id, | |
312 | grant_ref_t ref, | |
313 | uint32_t evtchn, | |
314 | struct socket *sock) | |
315 | { | |
316 | int ret; | |
317 | struct sock_mapping *map; | |
318 | void *page; | |
319 | ||
320 | map = kzalloc(sizeof(*map), GFP_KERNEL); | |
321 | if (map == NULL) | |
322 | return NULL; | |
323 | ||
324 | map->fedata = fedata; | |
325 | map->sock = sock; | |
326 | map->id = id; | |
327 | map->ref = ref; | |
328 | ||
329 | ret = xenbus_map_ring_valloc(fedata->dev, &ref, 1, &page); | |
330 | if (ret < 0) | |
331 | goto out; | |
332 | map->ring = page; | |
333 | map->ring_order = map->ring->ring_order; | |
334 | /* first read the order, then map the data ring */ | |
335 | virt_rmb(); | |
336 | if (map->ring_order > MAX_RING_ORDER) { | |
337 | pr_warn("%s frontend requested ring_order %u, which is > MAX (%u)\n", | |
338 | __func__, map->ring_order, MAX_RING_ORDER); | |
339 | goto out; | |
340 | } | |
341 | ret = xenbus_map_ring_valloc(fedata->dev, map->ring->ref, | |
342 | (1 << map->ring_order), &page); | |
343 | if (ret < 0) | |
344 | goto out; | |
345 | map->bytes = page; | |
346 | ||
347 | ret = bind_interdomain_evtchn_to_irqhandler(fedata->dev->otherend_id, | |
348 | evtchn, | |
349 | pvcalls_back_conn_event, | |
350 | 0, | |
351 | "pvcalls-backend", | |
352 | map); | |
353 | if (ret < 0) | |
354 | goto out; | |
355 | map->irq = ret; | |
356 | ||
357 | map->data.in = map->bytes; | |
358 | map->data.out = map->bytes + XEN_FLEX_RING_SIZE(map->ring_order); | |
359 | ||
360 | map->ioworker.wq = alloc_workqueue("pvcalls_io", WQ_UNBOUND, 1); | |
361 | if (!map->ioworker.wq) | |
362 | goto out; | |
363 | atomic_set(&map->io, 1); | |
364 | INIT_WORK(&map->ioworker.register_work, pvcalls_back_ioworker); | |
365 | ||
366 | down(&fedata->socket_lock); | |
367 | list_add_tail(&map->list, &fedata->socket_mappings); | |
368 | up(&fedata->socket_lock); | |
369 | ||
370 | write_lock_bh(&map->sock->sk->sk_callback_lock); | |
371 | map->saved_data_ready = map->sock->sk->sk_data_ready; | |
372 | map->sock->sk->sk_user_data = map; | |
373 | map->sock->sk->sk_data_ready = pvcalls_sk_data_ready; | |
374 | map->sock->sk->sk_state_change = pvcalls_sk_state_change; | |
375 | write_unlock_bh(&map->sock->sk->sk_callback_lock); | |
376 | ||
377 | return map; | |
378 | out: | |
379 | down(&fedata->socket_lock); | |
380 | list_del(&map->list); | |
381 | pvcalls_back_release_active(fedata->dev, fedata, map); | |
382 | up(&fedata->socket_lock); | |
383 | return NULL; | |
384 | } | |
385 | ||
b1efa693 SS |
386 | static int pvcalls_back_connect(struct xenbus_device *dev, |
387 | struct xen_pvcalls_request *req) | |
5db4d286 SS |
388 | { |
389 | struct pvcalls_fedata *fedata; | |
390 | int ret = -EINVAL; | |
391 | struct socket *sock; | |
392 | struct sock_mapping *map; | |
393 | struct xen_pvcalls_response *rsp; | |
394 | struct sockaddr *sa = (struct sockaddr *)&req->u.connect.addr; | |
395 | ||
396 | fedata = dev_get_drvdata(&dev->dev); | |
397 | ||
398 | if (req->u.connect.len < sizeof(sa->sa_family) || | |
399 | req->u.connect.len > sizeof(req->u.connect.addr) || | |
400 | sa->sa_family != AF_INET) | |
401 | goto out; | |
402 | ||
403 | ret = sock_create(AF_INET, SOCK_STREAM, 0, &sock); | |
404 | if (ret < 0) | |
405 | goto out; | |
406 | ret = inet_stream_connect(sock, sa, req->u.connect.len, 0); | |
407 | if (ret < 0) { | |
408 | sock_release(sock); | |
409 | goto out; | |
410 | } | |
411 | ||
412 | map = pvcalls_new_active_socket(fedata, | |
413 | req->u.connect.id, | |
414 | req->u.connect.ref, | |
415 | req->u.connect.evtchn, | |
416 | sock); | |
417 | if (!map) { | |
418 | ret = -EFAULT; | |
419 | sock_release(map->sock); | |
420 | } | |
421 | ||
422 | out: | |
423 | rsp = RING_GET_RESPONSE(&fedata->ring, fedata->ring.rsp_prod_pvt++); | |
424 | rsp->req_id = req->req_id; | |
425 | rsp->cmd = req->cmd; | |
426 | rsp->u.connect.id = req->u.connect.id; | |
427 | rsp->ret = ret; | |
428 | ||
429 | return 0; | |
430 | } | |
431 | ||
432 | static int pvcalls_back_release_active(struct xenbus_device *dev, | |
433 | struct pvcalls_fedata *fedata, | |
434 | struct sock_mapping *map) | |
b1efa693 | 435 | { |
a51729cb SS |
436 | disable_irq(map->irq); |
437 | if (map->sock->sk != NULL) { | |
438 | write_lock_bh(&map->sock->sk->sk_callback_lock); | |
439 | map->sock->sk->sk_user_data = NULL; | |
440 | map->sock->sk->sk_data_ready = map->saved_data_ready; | |
441 | write_unlock_bh(&map->sock->sk->sk_callback_lock); | |
442 | } | |
443 | ||
444 | atomic_set(&map->release, 1); | |
445 | flush_work(&map->ioworker.register_work); | |
446 | ||
447 | xenbus_unmap_ring_vfree(dev, map->bytes); | |
448 | xenbus_unmap_ring_vfree(dev, (void *)map->ring); | |
449 | unbind_from_irqhandler(map->irq, map); | |
450 | ||
451 | sock_release(map->sock); | |
452 | kfree(map); | |
453 | ||
454 | return 0; | |
455 | } | |
456 | ||
457 | static int pvcalls_back_release_passive(struct xenbus_device *dev, | |
458 | struct pvcalls_fedata *fedata, | |
459 | struct sockpass_mapping *mappass) | |
460 | { | |
461 | if (mappass->sock->sk != NULL) { | |
462 | write_lock_bh(&mappass->sock->sk->sk_callback_lock); | |
463 | mappass->sock->sk->sk_user_data = NULL; | |
464 | mappass->sock->sk->sk_data_ready = mappass->saved_data_ready; | |
465 | write_unlock_bh(&mappass->sock->sk->sk_callback_lock); | |
466 | } | |
467 | sock_release(mappass->sock); | |
468 | flush_workqueue(mappass->wq); | |
469 | destroy_workqueue(mappass->wq); | |
470 | kfree(mappass); | |
471 | ||
b1efa693 SS |
472 | return 0; |
473 | } | |
474 | ||
475 | static int pvcalls_back_release(struct xenbus_device *dev, | |
476 | struct xen_pvcalls_request *req) | |
477 | { | |
a51729cb SS |
478 | struct pvcalls_fedata *fedata; |
479 | struct sock_mapping *map, *n; | |
480 | struct sockpass_mapping *mappass; | |
481 | int ret = 0; | |
482 | struct xen_pvcalls_response *rsp; | |
483 | ||
484 | fedata = dev_get_drvdata(&dev->dev); | |
485 | ||
486 | down(&fedata->socket_lock); | |
487 | list_for_each_entry_safe(map, n, &fedata->socket_mappings, list) { | |
488 | if (map->id == req->u.release.id) { | |
489 | list_del(&map->list); | |
490 | up(&fedata->socket_lock); | |
491 | ret = pvcalls_back_release_active(dev, fedata, map); | |
492 | goto out; | |
493 | } | |
494 | } | |
495 | mappass = radix_tree_lookup(&fedata->socketpass_mappings, | |
496 | req->u.release.id); | |
497 | if (mappass != NULL) { | |
498 | radix_tree_delete(&fedata->socketpass_mappings, mappass->id); | |
499 | up(&fedata->socket_lock); | |
500 | ret = pvcalls_back_release_passive(dev, fedata, mappass); | |
501 | } else | |
502 | up(&fedata->socket_lock); | |
503 | ||
504 | out: | |
505 | rsp = RING_GET_RESPONSE(&fedata->ring, fedata->ring.rsp_prod_pvt++); | |
506 | rsp->req_id = req->req_id; | |
507 | rsp->u.release.id = req->u.release.id; | |
508 | rsp->cmd = req->cmd; | |
509 | rsp->ret = ret; | |
b1efa693 SS |
510 | return 0; |
511 | } | |
512 | ||
331a63e6 SS |
513 | static void __pvcalls_back_accept(struct work_struct *work) |
514 | { | |
6f474e71 SS |
515 | struct sockpass_mapping *mappass = container_of( |
516 | work, struct sockpass_mapping, register_work); | |
517 | struct sock_mapping *map; | |
518 | struct pvcalls_ioworker *iow; | |
519 | struct pvcalls_fedata *fedata; | |
520 | struct socket *sock; | |
521 | struct xen_pvcalls_response *rsp; | |
522 | struct xen_pvcalls_request *req; | |
523 | int notify; | |
524 | int ret = -EINVAL; | |
525 | unsigned long flags; | |
526 | ||
527 | fedata = mappass->fedata; | |
528 | /* | |
529 | * __pvcalls_back_accept can race against pvcalls_back_accept. | |
530 | * We only need to check the value of "cmd" on read. It could be | |
531 | * done atomically, but to simplify the code on the write side, we | |
532 | * use a spinlock. | |
533 | */ | |
534 | spin_lock_irqsave(&mappass->copy_lock, flags); | |
535 | req = &mappass->reqcopy; | |
536 | if (req->cmd != PVCALLS_ACCEPT) { | |
537 | spin_unlock_irqrestore(&mappass->copy_lock, flags); | |
538 | return; | |
539 | } | |
540 | spin_unlock_irqrestore(&mappass->copy_lock, flags); | |
541 | ||
542 | sock = sock_alloc(); | |
543 | if (sock == NULL) | |
544 | goto out_error; | |
545 | sock->type = mappass->sock->type; | |
546 | sock->ops = mappass->sock->ops; | |
547 | ||
548 | ret = inet_accept(mappass->sock, sock, O_NONBLOCK, true); | |
549 | if (ret == -EAGAIN) { | |
550 | sock_release(sock); | |
76119125 | 551 | return; |
6f474e71 SS |
552 | } |
553 | ||
554 | map = pvcalls_new_active_socket(fedata, | |
555 | req->u.accept.id_new, | |
556 | req->u.accept.ref, | |
557 | req->u.accept.evtchn, | |
558 | sock); | |
559 | if (!map) { | |
560 | ret = -EFAULT; | |
561 | sock_release(sock); | |
562 | goto out_error; | |
563 | } | |
564 | ||
565 | map->sockpass = mappass; | |
566 | iow = &map->ioworker; | |
567 | atomic_inc(&map->read); | |
568 | atomic_inc(&map->io); | |
569 | queue_work(iow->wq, &iow->register_work); | |
570 | ||
571 | out_error: | |
572 | rsp = RING_GET_RESPONSE(&fedata->ring, fedata->ring.rsp_prod_pvt++); | |
573 | rsp->req_id = req->req_id; | |
574 | rsp->cmd = req->cmd; | |
575 | rsp->u.accept.id = req->u.accept.id; | |
576 | rsp->ret = ret; | |
577 | RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&fedata->ring, notify); | |
578 | if (notify) | |
579 | notify_remote_via_irq(fedata->irq); | |
580 | ||
581 | mappass->reqcopy.cmd = 0; | |
331a63e6 SS |
582 | } |
583 | ||
584 | static void pvcalls_pass_sk_data_ready(struct sock *sock) | |
585 | { | |
6f474e71 | 586 | struct sockpass_mapping *mappass = sock->sk_user_data; |
3cf33a58 SS |
587 | struct pvcalls_fedata *fedata; |
588 | struct xen_pvcalls_response *rsp; | |
589 | unsigned long flags; | |
590 | int notify; | |
6f474e71 SS |
591 | |
592 | if (mappass == NULL) | |
593 | return; | |
594 | ||
3cf33a58 SS |
595 | fedata = mappass->fedata; |
596 | spin_lock_irqsave(&mappass->copy_lock, flags); | |
597 | if (mappass->reqcopy.cmd == PVCALLS_POLL) { | |
598 | rsp = RING_GET_RESPONSE(&fedata->ring, | |
599 | fedata->ring.rsp_prod_pvt++); | |
600 | rsp->req_id = mappass->reqcopy.req_id; | |
601 | rsp->u.poll.id = mappass->reqcopy.u.poll.id; | |
602 | rsp->cmd = mappass->reqcopy.cmd; | |
603 | rsp->ret = 0; | |
604 | ||
605 | mappass->reqcopy.cmd = 0; | |
606 | spin_unlock_irqrestore(&mappass->copy_lock, flags); | |
607 | ||
608 | RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&fedata->ring, notify); | |
609 | if (notify) | |
610 | notify_remote_via_irq(mappass->fedata->irq); | |
611 | } else { | |
612 | spin_unlock_irqrestore(&mappass->copy_lock, flags); | |
613 | queue_work(mappass->wq, &mappass->register_work); | |
614 | } | |
331a63e6 SS |
615 | } |
616 | ||
b1efa693 SS |
617 | static int pvcalls_back_bind(struct xenbus_device *dev, |
618 | struct xen_pvcalls_request *req) | |
619 | { | |
331a63e6 SS |
620 | struct pvcalls_fedata *fedata; |
621 | int ret; | |
622 | struct sockpass_mapping *map; | |
623 | struct xen_pvcalls_response *rsp; | |
624 | ||
625 | fedata = dev_get_drvdata(&dev->dev); | |
626 | ||
627 | map = kzalloc(sizeof(*map), GFP_KERNEL); | |
628 | if (map == NULL) { | |
629 | ret = -ENOMEM; | |
630 | goto out; | |
631 | } | |
632 | ||
633 | INIT_WORK(&map->register_work, __pvcalls_back_accept); | |
634 | spin_lock_init(&map->copy_lock); | |
635 | map->wq = alloc_workqueue("pvcalls_wq", WQ_UNBOUND, 1); | |
636 | if (!map->wq) { | |
637 | ret = -ENOMEM; | |
638 | goto out; | |
639 | } | |
640 | ||
641 | ret = sock_create(AF_INET, SOCK_STREAM, 0, &map->sock); | |
642 | if (ret < 0) | |
643 | goto out; | |
644 | ||
645 | ret = inet_bind(map->sock, (struct sockaddr *)&req->u.bind.addr, | |
646 | req->u.bind.len); | |
647 | if (ret < 0) | |
648 | goto out; | |
649 | ||
650 | map->fedata = fedata; | |
651 | map->id = req->u.bind.id; | |
652 | ||
653 | down(&fedata->socket_lock); | |
654 | ret = radix_tree_insert(&fedata->socketpass_mappings, map->id, | |
655 | map); | |
656 | up(&fedata->socket_lock); | |
657 | if (ret) | |
658 | goto out; | |
659 | ||
660 | write_lock_bh(&map->sock->sk->sk_callback_lock); | |
661 | map->saved_data_ready = map->sock->sk->sk_data_ready; | |
662 | map->sock->sk->sk_user_data = map; | |
663 | map->sock->sk->sk_data_ready = pvcalls_pass_sk_data_ready; | |
664 | write_unlock_bh(&map->sock->sk->sk_callback_lock); | |
665 | ||
666 | out: | |
667 | if (ret) { | |
668 | if (map && map->sock) | |
669 | sock_release(map->sock); | |
670 | if (map && map->wq) | |
671 | destroy_workqueue(map->wq); | |
672 | kfree(map); | |
673 | } | |
674 | rsp = RING_GET_RESPONSE(&fedata->ring, fedata->ring.rsp_prod_pvt++); | |
675 | rsp->req_id = req->req_id; | |
676 | rsp->cmd = req->cmd; | |
677 | rsp->u.bind.id = req->u.bind.id; | |
678 | rsp->ret = ret; | |
b1efa693 SS |
679 | return 0; |
680 | } | |
681 | ||
682 | static int pvcalls_back_listen(struct xenbus_device *dev, | |
683 | struct xen_pvcalls_request *req) | |
684 | { | |
8ce3f762 SS |
685 | struct pvcalls_fedata *fedata; |
686 | int ret = -EINVAL; | |
687 | struct sockpass_mapping *map; | |
688 | struct xen_pvcalls_response *rsp; | |
689 | ||
690 | fedata = dev_get_drvdata(&dev->dev); | |
691 | ||
692 | down(&fedata->socket_lock); | |
693 | map = radix_tree_lookup(&fedata->socketpass_mappings, req->u.listen.id); | |
694 | up(&fedata->socket_lock); | |
695 | if (map == NULL) | |
696 | goto out; | |
697 | ||
698 | ret = inet_listen(map->sock, req->u.listen.backlog); | |
699 | ||
700 | out: | |
701 | rsp = RING_GET_RESPONSE(&fedata->ring, fedata->ring.rsp_prod_pvt++); | |
702 | rsp->req_id = req->req_id; | |
703 | rsp->cmd = req->cmd; | |
704 | rsp->u.listen.id = req->u.listen.id; | |
705 | rsp->ret = ret; | |
b1efa693 SS |
706 | return 0; |
707 | } | |
708 | ||
709 | static int pvcalls_back_accept(struct xenbus_device *dev, | |
710 | struct xen_pvcalls_request *req) | |
711 | { | |
6f474e71 SS |
712 | struct pvcalls_fedata *fedata; |
713 | struct sockpass_mapping *mappass; | |
714 | int ret = -EINVAL; | |
715 | struct xen_pvcalls_response *rsp; | |
716 | unsigned long flags; | |
717 | ||
718 | fedata = dev_get_drvdata(&dev->dev); | |
719 | ||
720 | down(&fedata->socket_lock); | |
721 | mappass = radix_tree_lookup(&fedata->socketpass_mappings, | |
722 | req->u.accept.id); | |
723 | up(&fedata->socket_lock); | |
724 | if (mappass == NULL) | |
725 | goto out_error; | |
726 | ||
727 | /* | |
728 | * Limitation of the current implementation: only support one | |
729 | * concurrent accept or poll call on one socket. | |
730 | */ | |
731 | spin_lock_irqsave(&mappass->copy_lock, flags); | |
732 | if (mappass->reqcopy.cmd != 0) { | |
733 | spin_unlock_irqrestore(&mappass->copy_lock, flags); | |
734 | ret = -EINTR; | |
735 | goto out_error; | |
736 | } | |
737 | ||
738 | mappass->reqcopy = *req; | |
739 | spin_unlock_irqrestore(&mappass->copy_lock, flags); | |
740 | queue_work(mappass->wq, &mappass->register_work); | |
741 | ||
742 | /* Tell the caller we don't need to send back a notification yet */ | |
743 | return -1; | |
744 | ||
745 | out_error: | |
746 | rsp = RING_GET_RESPONSE(&fedata->ring, fedata->ring.rsp_prod_pvt++); | |
747 | rsp->req_id = req->req_id; | |
748 | rsp->cmd = req->cmd; | |
749 | rsp->u.accept.id = req->u.accept.id; | |
750 | rsp->ret = ret; | |
b1efa693 SS |
751 | return 0; |
752 | } | |
753 | ||
754 | static int pvcalls_back_poll(struct xenbus_device *dev, | |
755 | struct xen_pvcalls_request *req) | |
756 | { | |
3cf33a58 SS |
757 | struct pvcalls_fedata *fedata; |
758 | struct sockpass_mapping *mappass; | |
759 | struct xen_pvcalls_response *rsp; | |
760 | struct inet_connection_sock *icsk; | |
761 | struct request_sock_queue *queue; | |
762 | unsigned long flags; | |
763 | int ret; | |
764 | bool data; | |
765 | ||
766 | fedata = dev_get_drvdata(&dev->dev); | |
767 | ||
768 | down(&fedata->socket_lock); | |
769 | mappass = radix_tree_lookup(&fedata->socketpass_mappings, | |
770 | req->u.poll.id); | |
771 | up(&fedata->socket_lock); | |
772 | if (mappass == NULL) | |
773 | return -EINVAL; | |
774 | ||
775 | /* | |
776 | * Limitation of the current implementation: only support one | |
777 | * concurrent accept or poll call on one socket. | |
778 | */ | |
779 | spin_lock_irqsave(&mappass->copy_lock, flags); | |
780 | if (mappass->reqcopy.cmd != 0) { | |
781 | ret = -EINTR; | |
782 | goto out; | |
783 | } | |
784 | ||
785 | mappass->reqcopy = *req; | |
786 | icsk = inet_csk(mappass->sock->sk); | |
787 | queue = &icsk->icsk_accept_queue; | |
788 | data = queue->rskq_accept_head != NULL; | |
789 | if (data) { | |
790 | mappass->reqcopy.cmd = 0; | |
791 | ret = 0; | |
792 | goto out; | |
793 | } | |
794 | spin_unlock_irqrestore(&mappass->copy_lock, flags); | |
795 | ||
796 | /* Tell the caller we don't need to send back a notification yet */ | |
797 | return -1; | |
798 | ||
799 | out: | |
800 | spin_unlock_irqrestore(&mappass->copy_lock, flags); | |
801 | ||
802 | rsp = RING_GET_RESPONSE(&fedata->ring, fedata->ring.rsp_prod_pvt++); | |
803 | rsp->req_id = req->req_id; | |
804 | rsp->cmd = req->cmd; | |
805 | rsp->u.poll.id = req->u.poll.id; | |
806 | rsp->ret = ret; | |
b1efa693 SS |
807 | return 0; |
808 | } | |
809 | ||
810 | static int pvcalls_back_handle_cmd(struct xenbus_device *dev, | |
811 | struct xen_pvcalls_request *req) | |
812 | { | |
813 | int ret = 0; | |
814 | ||
815 | switch (req->cmd) { | |
816 | case PVCALLS_SOCKET: | |
817 | ret = pvcalls_back_socket(dev, req); | |
818 | break; | |
819 | case PVCALLS_CONNECT: | |
820 | ret = pvcalls_back_connect(dev, req); | |
821 | break; | |
822 | case PVCALLS_RELEASE: | |
823 | ret = pvcalls_back_release(dev, req); | |
824 | break; | |
825 | case PVCALLS_BIND: | |
826 | ret = pvcalls_back_bind(dev, req); | |
827 | break; | |
828 | case PVCALLS_LISTEN: | |
829 | ret = pvcalls_back_listen(dev, req); | |
830 | break; | |
831 | case PVCALLS_ACCEPT: | |
832 | ret = pvcalls_back_accept(dev, req); | |
833 | break; | |
834 | case PVCALLS_POLL: | |
835 | ret = pvcalls_back_poll(dev, req); | |
836 | break; | |
837 | default: | |
838 | { | |
839 | struct pvcalls_fedata *fedata; | |
840 | struct xen_pvcalls_response *rsp; | |
841 | ||
842 | fedata = dev_get_drvdata(&dev->dev); | |
843 | rsp = RING_GET_RESPONSE( | |
844 | &fedata->ring, fedata->ring.rsp_prod_pvt++); | |
845 | rsp->req_id = req->req_id; | |
846 | rsp->cmd = req->cmd; | |
847 | rsp->ret = -ENOTSUPP; | |
848 | break; | |
849 | } | |
850 | } | |
851 | return ret; | |
852 | } | |
853 | ||
854 | static void pvcalls_back_work(struct pvcalls_fedata *fedata) | |
855 | { | |
856 | int notify, notify_all = 0, more = 1; | |
857 | struct xen_pvcalls_request req; | |
858 | struct xenbus_device *dev = fedata->dev; | |
859 | ||
860 | while (more) { | |
861 | while (RING_HAS_UNCONSUMED_REQUESTS(&fedata->ring)) { | |
862 | RING_COPY_REQUEST(&fedata->ring, | |
863 | fedata->ring.req_cons++, | |
864 | &req); | |
865 | ||
866 | if (!pvcalls_back_handle_cmd(dev, &req)) { | |
867 | RING_PUSH_RESPONSES_AND_CHECK_NOTIFY( | |
868 | &fedata->ring, notify); | |
869 | notify_all += notify; | |
870 | } | |
871 | } | |
872 | ||
873 | if (notify_all) { | |
874 | notify_remote_via_irq(fedata->irq); | |
875 | notify_all = 0; | |
876 | } | |
877 | ||
878 | RING_FINAL_CHECK_FOR_REQUESTS(&fedata->ring, more); | |
879 | } | |
880 | } | |
881 | ||
d0e4d560 SS |
882 | static irqreturn_t pvcalls_back_event(int irq, void *dev_id) |
883 | { | |
b1efa693 SS |
884 | struct xenbus_device *dev = dev_id; |
885 | struct pvcalls_fedata *fedata = NULL; | |
886 | ||
887 | if (dev == NULL) | |
888 | return IRQ_HANDLED; | |
889 | ||
890 | fedata = dev_get_drvdata(&dev->dev); | |
891 | if (fedata == NULL) | |
892 | return IRQ_HANDLED; | |
893 | ||
894 | pvcalls_back_work(fedata); | |
d0e4d560 SS |
895 | return IRQ_HANDLED; |
896 | } | |
897 | ||
5db4d286 SS |
898 | static irqreturn_t pvcalls_back_conn_event(int irq, void *sock_map) |
899 | { | |
5ad9918f SS |
900 | struct sock_mapping *map = sock_map; |
901 | struct pvcalls_ioworker *iow; | |
902 | ||
903 | if (map == NULL || map->sock == NULL || map->sock->sk == NULL || | |
904 | map->sock->sk->sk_user_data != map) | |
905 | return IRQ_HANDLED; | |
906 | ||
907 | iow = &map->ioworker; | |
908 | ||
909 | atomic_inc(&map->write); | |
910 | atomic_inc(&map->io); | |
911 | queue_work(iow->wq, &iow->register_work); | |
912 | ||
5db4d286 SS |
913 | return IRQ_HANDLED; |
914 | } | |
915 | ||
0a9c75c2 SS |
916 | static int backend_connect(struct xenbus_device *dev) |
917 | { | |
d0e4d560 SS |
918 | int err, evtchn; |
919 | grant_ref_t ring_ref; | |
920 | struct pvcalls_fedata *fedata = NULL; | |
921 | ||
922 | fedata = kzalloc(sizeof(struct pvcalls_fedata), GFP_KERNEL); | |
923 | if (!fedata) | |
924 | return -ENOMEM; | |
925 | ||
926 | fedata->irq = -1; | |
927 | err = xenbus_scanf(XBT_NIL, dev->otherend, "port", "%u", | |
928 | &evtchn); | |
929 | if (err != 1) { | |
930 | err = -EINVAL; | |
931 | xenbus_dev_fatal(dev, err, "reading %s/event-channel", | |
932 | dev->otherend); | |
933 | goto error; | |
934 | } | |
935 | ||
936 | err = xenbus_scanf(XBT_NIL, dev->otherend, "ring-ref", "%u", &ring_ref); | |
937 | if (err != 1) { | |
938 | err = -EINVAL; | |
939 | xenbus_dev_fatal(dev, err, "reading %s/ring-ref", | |
940 | dev->otherend); | |
941 | goto error; | |
942 | } | |
943 | ||
944 | err = bind_interdomain_evtchn_to_irq(dev->otherend_id, evtchn); | |
945 | if (err < 0) | |
946 | goto error; | |
947 | fedata->irq = err; | |
948 | ||
949 | err = request_threaded_irq(fedata->irq, NULL, pvcalls_back_event, | |
950 | IRQF_ONESHOT, "pvcalls-back", dev); | |
951 | if (err < 0) | |
952 | goto error; | |
953 | ||
954 | err = xenbus_map_ring_valloc(dev, &ring_ref, 1, | |
955 | (void **)&fedata->sring); | |
956 | if (err < 0) | |
957 | goto error; | |
958 | ||
959 | BACK_RING_INIT(&fedata->ring, fedata->sring, XEN_PAGE_SIZE * 1); | |
960 | fedata->dev = dev; | |
961 | ||
962 | INIT_LIST_HEAD(&fedata->socket_mappings); | |
963 | INIT_RADIX_TREE(&fedata->socketpass_mappings, GFP_KERNEL); | |
964 | sema_init(&fedata->socket_lock, 1); | |
965 | dev_set_drvdata(&dev->dev, fedata); | |
966 | ||
967 | down(&pvcalls_back_global.frontends_lock); | |
968 | list_add_tail(&fedata->list, &pvcalls_back_global.frontends); | |
969 | up(&pvcalls_back_global.frontends_lock); | |
970 | ||
0a9c75c2 | 971 | return 0; |
d0e4d560 SS |
972 | |
973 | error: | |
974 | if (fedata->irq >= 0) | |
975 | unbind_from_irqhandler(fedata->irq, dev); | |
976 | if (fedata->sring != NULL) | |
977 | xenbus_unmap_ring_vfree(dev, fedata->sring); | |
978 | kfree(fedata); | |
979 | return err; | |
0a9c75c2 SS |
980 | } |
981 | ||
982 | static int backend_disconnect(struct xenbus_device *dev) | |
983 | { | |
0a85d23b SS |
984 | struct pvcalls_fedata *fedata; |
985 | struct sock_mapping *map, *n; | |
986 | struct sockpass_mapping *mappass; | |
987 | struct radix_tree_iter iter; | |
988 | void **slot; | |
989 | ||
990 | ||
991 | fedata = dev_get_drvdata(&dev->dev); | |
992 | ||
993 | down(&fedata->socket_lock); | |
994 | list_for_each_entry_safe(map, n, &fedata->socket_mappings, list) { | |
995 | list_del(&map->list); | |
996 | pvcalls_back_release_active(dev, fedata, map); | |
997 | } | |
998 | ||
999 | radix_tree_for_each_slot(slot, &fedata->socketpass_mappings, &iter, 0) { | |
1000 | mappass = radix_tree_deref_slot(slot); | |
1001 | if (!mappass) | |
1002 | continue; | |
1003 | if (radix_tree_exception(mappass)) { | |
1004 | if (radix_tree_deref_retry(mappass)) | |
1005 | slot = radix_tree_iter_retry(&iter); | |
1006 | } else { | |
1007 | radix_tree_delete(&fedata->socketpass_mappings, | |
1008 | mappass->id); | |
1009 | pvcalls_back_release_passive(dev, fedata, mappass); | |
1010 | } | |
1011 | } | |
1012 | up(&fedata->socket_lock); | |
1013 | ||
1014 | unbind_from_irqhandler(fedata->irq, dev); | |
1015 | xenbus_unmap_ring_vfree(dev, fedata->sring); | |
1016 | ||
1017 | list_del(&fedata->list); | |
1018 | kfree(fedata); | |
1019 | dev_set_drvdata(&dev->dev, NULL); | |
1020 | ||
0a9c75c2 SS |
1021 | return 0; |
1022 | } | |
1023 | ||
72e59c30 SS |
1024 | static int pvcalls_back_probe(struct xenbus_device *dev, |
1025 | const struct xenbus_device_id *id) | |
1026 | { | |
0a9c75c2 SS |
1027 | int err, abort; |
1028 | struct xenbus_transaction xbt; | |
1029 | ||
1030 | again: | |
1031 | abort = 1; | |
1032 | ||
1033 | err = xenbus_transaction_start(&xbt); | |
1034 | if (err) { | |
1035 | pr_warn("%s cannot create xenstore transaction\n", __func__); | |
1036 | return err; | |
1037 | } | |
1038 | ||
1039 | err = xenbus_printf(xbt, dev->nodename, "versions", "%s", | |
1040 | PVCALLS_VERSIONS); | |
1041 | if (err) { | |
1042 | pr_warn("%s write out 'versions' failed\n", __func__); | |
1043 | goto abort; | |
1044 | } | |
1045 | ||
1046 | err = xenbus_printf(xbt, dev->nodename, "max-page-order", "%u", | |
1047 | MAX_RING_ORDER); | |
1048 | if (err) { | |
1049 | pr_warn("%s write out 'max-page-order' failed\n", __func__); | |
1050 | goto abort; | |
1051 | } | |
1052 | ||
1053 | err = xenbus_printf(xbt, dev->nodename, "function-calls", | |
1054 | XENBUS_FUNCTIONS_CALLS); | |
1055 | if (err) { | |
1056 | pr_warn("%s write out 'function-calls' failed\n", __func__); | |
1057 | goto abort; | |
1058 | } | |
1059 | ||
1060 | abort = 0; | |
1061 | abort: | |
1062 | err = xenbus_transaction_end(xbt, abort); | |
1063 | if (err) { | |
1064 | if (err == -EAGAIN && !abort) | |
1065 | goto again; | |
1066 | pr_warn("%s cannot complete xenstore transaction\n", __func__); | |
1067 | return err; | |
1068 | } | |
1069 | ||
1070 | if (abort) | |
1071 | return -EFAULT; | |
1072 | ||
1073 | xenbus_switch_state(dev, XenbusStateInitWait); | |
1074 | ||
72e59c30 SS |
1075 | return 0; |
1076 | } | |
1077 | ||
0a9c75c2 SS |
1078 | static void set_backend_state(struct xenbus_device *dev, |
1079 | enum xenbus_state state) | |
1080 | { | |
1081 | while (dev->state != state) { | |
1082 | switch (dev->state) { | |
1083 | case XenbusStateClosed: | |
1084 | switch (state) { | |
1085 | case XenbusStateInitWait: | |
1086 | case XenbusStateConnected: | |
1087 | xenbus_switch_state(dev, XenbusStateInitWait); | |
1088 | break; | |
1089 | case XenbusStateClosing: | |
1090 | xenbus_switch_state(dev, XenbusStateClosing); | |
1091 | break; | |
1092 | default: | |
fefcfb99 | 1093 | WARN_ON(1); |
0a9c75c2 SS |
1094 | } |
1095 | break; | |
1096 | case XenbusStateInitWait: | |
1097 | case XenbusStateInitialised: | |
1098 | switch (state) { | |
1099 | case XenbusStateConnected: | |
1100 | backend_connect(dev); | |
1101 | xenbus_switch_state(dev, XenbusStateConnected); | |
1102 | break; | |
1103 | case XenbusStateClosing: | |
1104 | case XenbusStateClosed: | |
1105 | xenbus_switch_state(dev, XenbusStateClosing); | |
1106 | break; | |
1107 | default: | |
fefcfb99 | 1108 | WARN_ON(1); |
0a9c75c2 SS |
1109 | } |
1110 | break; | |
1111 | case XenbusStateConnected: | |
1112 | switch (state) { | |
1113 | case XenbusStateInitWait: | |
1114 | case XenbusStateClosing: | |
1115 | case XenbusStateClosed: | |
1116 | down(&pvcalls_back_global.frontends_lock); | |
1117 | backend_disconnect(dev); | |
1118 | up(&pvcalls_back_global.frontends_lock); | |
1119 | xenbus_switch_state(dev, XenbusStateClosing); | |
1120 | break; | |
1121 | default: | |
fefcfb99 | 1122 | WARN_ON(1); |
0a9c75c2 SS |
1123 | } |
1124 | break; | |
1125 | case XenbusStateClosing: | |
1126 | switch (state) { | |
1127 | case XenbusStateInitWait: | |
1128 | case XenbusStateConnected: | |
1129 | case XenbusStateClosed: | |
1130 | xenbus_switch_state(dev, XenbusStateClosed); | |
1131 | break; | |
1132 | default: | |
fefcfb99 | 1133 | WARN_ON(1); |
0a9c75c2 SS |
1134 | } |
1135 | break; | |
1136 | default: | |
fefcfb99 | 1137 | WARN_ON(1); |
0a9c75c2 SS |
1138 | } |
1139 | } | |
1140 | } | |
1141 | ||
72e59c30 SS |
1142 | static void pvcalls_back_changed(struct xenbus_device *dev, |
1143 | enum xenbus_state frontend_state) | |
1144 | { | |
0a9c75c2 SS |
1145 | switch (frontend_state) { |
1146 | case XenbusStateInitialising: | |
1147 | set_backend_state(dev, XenbusStateInitWait); | |
1148 | break; | |
1149 | ||
1150 | case XenbusStateInitialised: | |
1151 | case XenbusStateConnected: | |
1152 | set_backend_state(dev, XenbusStateConnected); | |
1153 | break; | |
1154 | ||
1155 | case XenbusStateClosing: | |
1156 | set_backend_state(dev, XenbusStateClosing); | |
1157 | break; | |
1158 | ||
1159 | case XenbusStateClosed: | |
1160 | set_backend_state(dev, XenbusStateClosed); | |
1161 | if (xenbus_dev_is_online(dev)) | |
1162 | break; | |
1163 | device_unregister(&dev->dev); | |
1164 | break; | |
1165 | case XenbusStateUnknown: | |
1166 | set_backend_state(dev, XenbusStateClosed); | |
1167 | device_unregister(&dev->dev); | |
1168 | break; | |
1169 | ||
1170 | default: | |
1171 | xenbus_dev_fatal(dev, -EINVAL, "saw state %d at frontend", | |
1172 | frontend_state); | |
1173 | break; | |
1174 | } | |
72e59c30 SS |
1175 | } |
1176 | ||
1177 | static int pvcalls_back_remove(struct xenbus_device *dev) | |
1178 | { | |
1179 | return 0; | |
1180 | } | |
1181 | ||
1182 | static int pvcalls_back_uevent(struct xenbus_device *xdev, | |
1183 | struct kobj_uevent_env *env) | |
1184 | { | |
1185 | return 0; | |
1186 | } | |
1187 | ||
1188 | static const struct xenbus_device_id pvcalls_back_ids[] = { | |
1189 | { "pvcalls" }, | |
1190 | { "" } | |
1191 | }; | |
1192 | ||
1193 | static struct xenbus_driver pvcalls_back_driver = { | |
1194 | .ids = pvcalls_back_ids, | |
1195 | .probe = pvcalls_back_probe, | |
1196 | .remove = pvcalls_back_remove, | |
1197 | .uevent = pvcalls_back_uevent, | |
1198 | .otherend_changed = pvcalls_back_changed, | |
1199 | }; | |
9be07334 SS |
1200 | |
1201 | static int __init pvcalls_back_init(void) | |
1202 | { | |
1203 | int ret; | |
1204 | ||
1205 | if (!xen_domain()) | |
1206 | return -ENODEV; | |
1207 | ||
1208 | ret = xenbus_register_backend(&pvcalls_back_driver); | |
1209 | if (ret < 0) | |
1210 | return ret; | |
1211 | ||
1212 | sema_init(&pvcalls_back_global.frontends_lock, 1); | |
1213 | INIT_LIST_HEAD(&pvcalls_back_global.frontends); | |
1214 | return 0; | |
1215 | } | |
1216 | module_init(pvcalls_back_init); | |
0a85d23b SS |
1217 | |
1218 | static void __exit pvcalls_back_fin(void) | |
1219 | { | |
1220 | struct pvcalls_fedata *fedata, *nfedata; | |
1221 | ||
1222 | down(&pvcalls_back_global.frontends_lock); | |
1223 | list_for_each_entry_safe(fedata, nfedata, | |
1224 | &pvcalls_back_global.frontends, list) { | |
1225 | backend_disconnect(fedata->dev); | |
1226 | } | |
1227 | up(&pvcalls_back_global.frontends_lock); | |
1228 | ||
1229 | xenbus_unregister_driver(&pvcalls_back_driver); | |
1230 | } | |
1231 | ||
1232 | module_exit(pvcalls_back_fin); | |
24e7f84d BO |
1233 | |
1234 | MODULE_DESCRIPTION("Xen PV Calls backend driver"); | |
1235 | MODULE_AUTHOR("Stefano Stabellini <sstabellini@kernel.org>"); | |
1236 | MODULE_LICENSE("GPL"); |