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c942fddf | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
72e59c30 SS |
2 | /* |
3 | * (c) 2017 Stefano Stabellini <stefano@aporeto.com> | |
72e59c30 SS |
4 | */ |
5 | ||
fb029875 | 6 | #include <linux/inet.h> |
72e59c30 SS |
7 | #include <linux/kthread.h> |
8 | #include <linux/list.h> | |
9 | #include <linux/radix-tree.h> | |
10 | #include <linux/module.h> | |
11 | #include <linux/semaphore.h> | |
12 | #include <linux/wait.h> | |
fb029875 SS |
13 | #include <net/sock.h> |
14 | #include <net/inet_common.h> | |
15 | #include <net/inet_connection_sock.h> | |
16 | #include <net/request_sock.h> | |
72e59c30 SS |
17 | |
18 | #include <xen/events.h> | |
19 | #include <xen/grant_table.h> | |
20 | #include <xen/xen.h> | |
21 | #include <xen/xenbus.h> | |
22 | #include <xen/interface/io/pvcalls.h> | |
23 | ||
0a9c75c2 SS |
24 | #define PVCALLS_VERSIONS "1" |
25 | #define MAX_RING_ORDER XENBUS_MAX_RING_GRANT_ORDER | |
26 | ||
9be07334 SS |
27 | struct pvcalls_back_global { |
28 | struct list_head frontends; | |
29 | struct semaphore frontends_lock; | |
30 | } pvcalls_back_global; | |
31 | ||
d0e4d560 SS |
32 | /* |
33 | * Per-frontend data structure. It contains pointers to the command | |
34 | * ring, its event channel, a list of active sockets and a tree of | |
35 | * passive sockets. | |
36 | */ | |
37 | struct pvcalls_fedata { | |
38 | struct list_head list; | |
39 | struct xenbus_device *dev; | |
40 | struct xen_pvcalls_sring *sring; | |
41 | struct xen_pvcalls_back_ring ring; | |
42 | int irq; | |
43 | struct list_head socket_mappings; | |
44 | struct radix_tree_root socketpass_mappings; | |
45 | struct semaphore socket_lock; | |
46 | }; | |
47 | ||
5db4d286 SS |
48 | struct pvcalls_ioworker { |
49 | struct work_struct register_work; | |
50 | struct workqueue_struct *wq; | |
51 | }; | |
52 | ||
53 | struct sock_mapping { | |
54 | struct list_head list; | |
55 | struct pvcalls_fedata *fedata; | |
6f474e71 | 56 | struct sockpass_mapping *sockpass; |
5db4d286 SS |
57 | struct socket *sock; |
58 | uint64_t id; | |
59 | grant_ref_t ref; | |
60 | struct pvcalls_data_intf *ring; | |
61 | void *bytes; | |
62 | struct pvcalls_data data; | |
63 | uint32_t ring_order; | |
64 | int irq; | |
65 | atomic_t read; | |
66 | atomic_t write; | |
67 | atomic_t io; | |
68 | atomic_t release; | |
69 | void (*saved_data_ready)(struct sock *sk); | |
70 | struct pvcalls_ioworker ioworker; | |
71 | }; | |
72 | ||
331a63e6 SS |
73 | struct sockpass_mapping { |
74 | struct list_head list; | |
75 | struct pvcalls_fedata *fedata; | |
76 | struct socket *sock; | |
77 | uint64_t id; | |
78 | struct xen_pvcalls_request reqcopy; | |
79 | spinlock_t copy_lock; | |
80 | struct workqueue_struct *wq; | |
81 | struct work_struct register_work; | |
82 | void (*saved_data_ready)(struct sock *sk); | |
83 | }; | |
84 | ||
5db4d286 SS |
85 | static irqreturn_t pvcalls_back_conn_event(int irq, void *sock_map); |
86 | static int pvcalls_back_release_active(struct xenbus_device *dev, | |
87 | struct pvcalls_fedata *fedata, | |
88 | struct sock_mapping *map); | |
89 | ||
5d520d85 SS |
90 | static void pvcalls_conn_back_read(void *opaque) |
91 | { | |
b3f9f773 SS |
92 | struct sock_mapping *map = (struct sock_mapping *)opaque; |
93 | struct msghdr msg; | |
94 | struct kvec vec[2]; | |
95 | RING_IDX cons, prod, size, wanted, array_size, masked_prod, masked_cons; | |
96 | int32_t error; | |
97 | struct pvcalls_data_intf *intf = map->ring; | |
98 | struct pvcalls_data *data = &map->data; | |
99 | unsigned long flags; | |
100 | int ret; | |
101 | ||
102 | array_size = XEN_FLEX_RING_SIZE(map->ring_order); | |
103 | cons = intf->in_cons; | |
104 | prod = intf->in_prod; | |
105 | error = intf->in_error; | |
106 | /* read the indexes first, then deal with the data */ | |
107 | virt_mb(); | |
108 | ||
109 | if (error) | |
110 | return; | |
111 | ||
112 | size = pvcalls_queued(prod, cons, array_size); | |
113 | if (size >= array_size) | |
114 | return; | |
115 | spin_lock_irqsave(&map->sock->sk->sk_receive_queue.lock, flags); | |
116 | if (skb_queue_empty(&map->sock->sk->sk_receive_queue)) { | |
117 | atomic_set(&map->read, 0); | |
118 | spin_unlock_irqrestore(&map->sock->sk->sk_receive_queue.lock, | |
119 | flags); | |
120 | return; | |
121 | } | |
122 | spin_unlock_irqrestore(&map->sock->sk->sk_receive_queue.lock, flags); | |
123 | wanted = array_size - size; | |
124 | masked_prod = pvcalls_mask(prod, array_size); | |
125 | masked_cons = pvcalls_mask(cons, array_size); | |
126 | ||
127 | memset(&msg, 0, sizeof(msg)); | |
b3f9f773 SS |
128 | if (masked_prod < masked_cons) { |
129 | vec[0].iov_base = data->in + masked_prod; | |
130 | vec[0].iov_len = wanted; | |
aa563d7b | 131 | iov_iter_kvec(&msg.msg_iter, WRITE, vec, 1, wanted); |
b3f9f773 SS |
132 | } else { |
133 | vec[0].iov_base = data->in + masked_prod; | |
134 | vec[0].iov_len = array_size - masked_prod; | |
135 | vec[1].iov_base = data->in; | |
136 | vec[1].iov_len = wanted - vec[0].iov_len; | |
aa563d7b | 137 | iov_iter_kvec(&msg.msg_iter, WRITE, vec, 2, wanted); |
b3f9f773 SS |
138 | } |
139 | ||
140 | atomic_set(&map->read, 0); | |
141 | ret = inet_recvmsg(map->sock, &msg, wanted, MSG_DONTWAIT); | |
142 | WARN_ON(ret > wanted); | |
143 | if (ret == -EAGAIN) /* shouldn't happen */ | |
144 | return; | |
145 | if (!ret) | |
146 | ret = -ENOTCONN; | |
147 | spin_lock_irqsave(&map->sock->sk->sk_receive_queue.lock, flags); | |
148 | if (ret > 0 && !skb_queue_empty(&map->sock->sk->sk_receive_queue)) | |
149 | atomic_inc(&map->read); | |
150 | spin_unlock_irqrestore(&map->sock->sk->sk_receive_queue.lock, flags); | |
151 | ||
152 | /* write the data, then modify the indexes */ | |
153 | virt_wmb(); | |
e6587cdb SS |
154 | if (ret < 0) { |
155 | atomic_set(&map->read, 0); | |
b3f9f773 | 156 | intf->in_error = ret; |
e6587cdb | 157 | } else |
b3f9f773 SS |
158 | intf->in_prod = prod + ret; |
159 | /* update the indexes, then notify the other end */ | |
160 | virt_wmb(); | |
161 | notify_remote_via_irq(map->irq); | |
162 | ||
163 | return; | |
5d520d85 SS |
164 | } |
165 | ||
166 | static void pvcalls_conn_back_write(struct sock_mapping *map) | |
167 | { | |
5ad9918f SS |
168 | struct pvcalls_data_intf *intf = map->ring; |
169 | struct pvcalls_data *data = &map->data; | |
170 | struct msghdr msg; | |
171 | struct kvec vec[2]; | |
172 | RING_IDX cons, prod, size, array_size; | |
173 | int ret; | |
174 | ||
175 | cons = intf->out_cons; | |
176 | prod = intf->out_prod; | |
177 | /* read the indexes before dealing with the data */ | |
178 | virt_mb(); | |
179 | ||
180 | array_size = XEN_FLEX_RING_SIZE(map->ring_order); | |
181 | size = pvcalls_queued(prod, cons, array_size); | |
182 | if (size == 0) | |
183 | return; | |
184 | ||
185 | memset(&msg, 0, sizeof(msg)); | |
186 | msg.msg_flags |= MSG_DONTWAIT; | |
5ad9918f SS |
187 | if (pvcalls_mask(prod, array_size) > pvcalls_mask(cons, array_size)) { |
188 | vec[0].iov_base = data->out + pvcalls_mask(cons, array_size); | |
189 | vec[0].iov_len = size; | |
aa563d7b | 190 | iov_iter_kvec(&msg.msg_iter, READ, vec, 1, size); |
5ad9918f SS |
191 | } else { |
192 | vec[0].iov_base = data->out + pvcalls_mask(cons, array_size); | |
193 | vec[0].iov_len = array_size - pvcalls_mask(cons, array_size); | |
194 | vec[1].iov_base = data->out; | |
195 | vec[1].iov_len = size - vec[0].iov_len; | |
aa563d7b | 196 | iov_iter_kvec(&msg.msg_iter, READ, vec, 2, size); |
5ad9918f SS |
197 | } |
198 | ||
199 | atomic_set(&map->write, 0); | |
200 | ret = inet_sendmsg(map->sock, &msg, size); | |
201 | if (ret == -EAGAIN || (ret >= 0 && ret < size)) { | |
202 | atomic_inc(&map->write); | |
203 | atomic_inc(&map->io); | |
204 | } | |
205 | if (ret == -EAGAIN) | |
206 | return; | |
207 | ||
208 | /* write the data, then update the indexes */ | |
209 | virt_wmb(); | |
210 | if (ret < 0) { | |
211 | intf->out_error = ret; | |
212 | } else { | |
213 | intf->out_error = 0; | |
214 | intf->out_cons = cons + ret; | |
215 | prod = intf->out_prod; | |
216 | } | |
217 | /* update the indexes, then notify the other end */ | |
218 | virt_wmb(); | |
219 | if (prod != cons + ret) | |
220 | atomic_inc(&map->write); | |
221 | notify_remote_via_irq(map->irq); | |
5d520d85 SS |
222 | } |
223 | ||
5db4d286 SS |
224 | static void pvcalls_back_ioworker(struct work_struct *work) |
225 | { | |
5d520d85 SS |
226 | struct pvcalls_ioworker *ioworker = container_of(work, |
227 | struct pvcalls_ioworker, register_work); | |
228 | struct sock_mapping *map = container_of(ioworker, struct sock_mapping, | |
229 | ioworker); | |
230 | ||
231 | while (atomic_read(&map->io) > 0) { | |
232 | if (atomic_read(&map->release) > 0) { | |
233 | atomic_set(&map->release, 0); | |
234 | return; | |
235 | } | |
236 | ||
237 | if (atomic_read(&map->read) > 0) | |
238 | pvcalls_conn_back_read(map); | |
239 | if (atomic_read(&map->write) > 0) | |
240 | pvcalls_conn_back_write(map); | |
241 | ||
242 | atomic_dec(&map->io); | |
243 | } | |
5db4d286 SS |
244 | } |
245 | ||
b1efa693 SS |
246 | static int pvcalls_back_socket(struct xenbus_device *dev, |
247 | struct xen_pvcalls_request *req) | |
248 | { | |
fb029875 SS |
249 | struct pvcalls_fedata *fedata; |
250 | int ret; | |
251 | struct xen_pvcalls_response *rsp; | |
252 | ||
253 | fedata = dev_get_drvdata(&dev->dev); | |
254 | ||
255 | if (req->u.socket.domain != AF_INET || | |
256 | req->u.socket.type != SOCK_STREAM || | |
257 | (req->u.socket.protocol != IPPROTO_IP && | |
258 | req->u.socket.protocol != AF_INET)) | |
259 | ret = -EAFNOSUPPORT; | |
260 | else | |
261 | ret = 0; | |
262 | ||
263 | /* leave the actual socket allocation for later */ | |
264 | ||
265 | rsp = RING_GET_RESPONSE(&fedata->ring, fedata->ring.rsp_prod_pvt++); | |
266 | rsp->req_id = req->req_id; | |
267 | rsp->cmd = req->cmd; | |
268 | rsp->u.socket.id = req->u.socket.id; | |
269 | rsp->ret = ret; | |
270 | ||
b1efa693 SS |
271 | return 0; |
272 | } | |
273 | ||
5db4d286 SS |
274 | static void pvcalls_sk_state_change(struct sock *sock) |
275 | { | |
276 | struct sock_mapping *map = sock->sk_user_data; | |
5db4d286 SS |
277 | |
278 | if (map == NULL) | |
279 | return; | |
280 | ||
e6587cdb | 281 | atomic_inc(&map->read); |
5db4d286 SS |
282 | notify_remote_via_irq(map->irq); |
283 | } | |
284 | ||
285 | static void pvcalls_sk_data_ready(struct sock *sock) | |
286 | { | |
b3f9f773 SS |
287 | struct sock_mapping *map = sock->sk_user_data; |
288 | struct pvcalls_ioworker *iow; | |
289 | ||
290 | if (map == NULL) | |
291 | return; | |
292 | ||
293 | iow = &map->ioworker; | |
294 | atomic_inc(&map->read); | |
295 | atomic_inc(&map->io); | |
296 | queue_work(iow->wq, &iow->register_work); | |
5db4d286 SS |
297 | } |
298 | ||
299 | static struct sock_mapping *pvcalls_new_active_socket( | |
300 | struct pvcalls_fedata *fedata, | |
301 | uint64_t id, | |
302 | grant_ref_t ref, | |
303 | uint32_t evtchn, | |
304 | struct socket *sock) | |
305 | { | |
306 | int ret; | |
307 | struct sock_mapping *map; | |
308 | void *page; | |
309 | ||
310 | map = kzalloc(sizeof(*map), GFP_KERNEL); | |
311 | if (map == NULL) | |
312 | return NULL; | |
313 | ||
314 | map->fedata = fedata; | |
315 | map->sock = sock; | |
316 | map->id = id; | |
317 | map->ref = ref; | |
318 | ||
319 | ret = xenbus_map_ring_valloc(fedata->dev, &ref, 1, &page); | |
320 | if (ret < 0) | |
321 | goto out; | |
322 | map->ring = page; | |
323 | map->ring_order = map->ring->ring_order; | |
324 | /* first read the order, then map the data ring */ | |
325 | virt_rmb(); | |
326 | if (map->ring_order > MAX_RING_ORDER) { | |
327 | pr_warn("%s frontend requested ring_order %u, which is > MAX (%u)\n", | |
328 | __func__, map->ring_order, MAX_RING_ORDER); | |
329 | goto out; | |
330 | } | |
331 | ret = xenbus_map_ring_valloc(fedata->dev, map->ring->ref, | |
332 | (1 << map->ring_order), &page); | |
333 | if (ret < 0) | |
334 | goto out; | |
335 | map->bytes = page; | |
336 | ||
337 | ret = bind_interdomain_evtchn_to_irqhandler(fedata->dev->otherend_id, | |
338 | evtchn, | |
339 | pvcalls_back_conn_event, | |
340 | 0, | |
341 | "pvcalls-backend", | |
342 | map); | |
343 | if (ret < 0) | |
344 | goto out; | |
345 | map->irq = ret; | |
346 | ||
347 | map->data.in = map->bytes; | |
348 | map->data.out = map->bytes + XEN_FLEX_RING_SIZE(map->ring_order); | |
349 | ||
350 | map->ioworker.wq = alloc_workqueue("pvcalls_io", WQ_UNBOUND, 1); | |
351 | if (!map->ioworker.wq) | |
352 | goto out; | |
353 | atomic_set(&map->io, 1); | |
354 | INIT_WORK(&map->ioworker.register_work, pvcalls_back_ioworker); | |
355 | ||
356 | down(&fedata->socket_lock); | |
357 | list_add_tail(&map->list, &fedata->socket_mappings); | |
358 | up(&fedata->socket_lock); | |
359 | ||
360 | write_lock_bh(&map->sock->sk->sk_callback_lock); | |
361 | map->saved_data_ready = map->sock->sk->sk_data_ready; | |
362 | map->sock->sk->sk_user_data = map; | |
363 | map->sock->sk->sk_data_ready = pvcalls_sk_data_ready; | |
364 | map->sock->sk->sk_state_change = pvcalls_sk_state_change; | |
365 | write_unlock_bh(&map->sock->sk->sk_callback_lock); | |
366 | ||
367 | return map; | |
368 | out: | |
369 | down(&fedata->socket_lock); | |
370 | list_del(&map->list); | |
371 | pvcalls_back_release_active(fedata->dev, fedata, map); | |
372 | up(&fedata->socket_lock); | |
373 | return NULL; | |
374 | } | |
375 | ||
b1efa693 SS |
376 | static int pvcalls_back_connect(struct xenbus_device *dev, |
377 | struct xen_pvcalls_request *req) | |
5db4d286 SS |
378 | { |
379 | struct pvcalls_fedata *fedata; | |
380 | int ret = -EINVAL; | |
381 | struct socket *sock; | |
382 | struct sock_mapping *map; | |
383 | struct xen_pvcalls_response *rsp; | |
384 | struct sockaddr *sa = (struct sockaddr *)&req->u.connect.addr; | |
385 | ||
386 | fedata = dev_get_drvdata(&dev->dev); | |
387 | ||
388 | if (req->u.connect.len < sizeof(sa->sa_family) || | |
389 | req->u.connect.len > sizeof(req->u.connect.addr) || | |
390 | sa->sa_family != AF_INET) | |
391 | goto out; | |
392 | ||
393 | ret = sock_create(AF_INET, SOCK_STREAM, 0, &sock); | |
394 | if (ret < 0) | |
395 | goto out; | |
396 | ret = inet_stream_connect(sock, sa, req->u.connect.len, 0); | |
397 | if (ret < 0) { | |
398 | sock_release(sock); | |
399 | goto out; | |
400 | } | |
401 | ||
402 | map = pvcalls_new_active_socket(fedata, | |
403 | req->u.connect.id, | |
404 | req->u.connect.ref, | |
405 | req->u.connect.evtchn, | |
406 | sock); | |
407 | if (!map) { | |
408 | ret = -EFAULT; | |
68d2059b | 409 | sock_release(sock); |
5db4d286 SS |
410 | } |
411 | ||
412 | out: | |
413 | rsp = RING_GET_RESPONSE(&fedata->ring, fedata->ring.rsp_prod_pvt++); | |
414 | rsp->req_id = req->req_id; | |
415 | rsp->cmd = req->cmd; | |
416 | rsp->u.connect.id = req->u.connect.id; | |
417 | rsp->ret = ret; | |
418 | ||
419 | return 0; | |
420 | } | |
421 | ||
422 | static int pvcalls_back_release_active(struct xenbus_device *dev, | |
423 | struct pvcalls_fedata *fedata, | |
424 | struct sock_mapping *map) | |
b1efa693 | 425 | { |
a51729cb SS |
426 | disable_irq(map->irq); |
427 | if (map->sock->sk != NULL) { | |
428 | write_lock_bh(&map->sock->sk->sk_callback_lock); | |
429 | map->sock->sk->sk_user_data = NULL; | |
430 | map->sock->sk->sk_data_ready = map->saved_data_ready; | |
431 | write_unlock_bh(&map->sock->sk->sk_callback_lock); | |
432 | } | |
433 | ||
434 | atomic_set(&map->release, 1); | |
435 | flush_work(&map->ioworker.register_work); | |
436 | ||
437 | xenbus_unmap_ring_vfree(dev, map->bytes); | |
438 | xenbus_unmap_ring_vfree(dev, (void *)map->ring); | |
439 | unbind_from_irqhandler(map->irq, map); | |
440 | ||
441 | sock_release(map->sock); | |
442 | kfree(map); | |
443 | ||
444 | return 0; | |
445 | } | |
446 | ||
447 | static int pvcalls_back_release_passive(struct xenbus_device *dev, | |
448 | struct pvcalls_fedata *fedata, | |
449 | struct sockpass_mapping *mappass) | |
450 | { | |
451 | if (mappass->sock->sk != NULL) { | |
452 | write_lock_bh(&mappass->sock->sk->sk_callback_lock); | |
453 | mappass->sock->sk->sk_user_data = NULL; | |
454 | mappass->sock->sk->sk_data_ready = mappass->saved_data_ready; | |
455 | write_unlock_bh(&mappass->sock->sk->sk_callback_lock); | |
456 | } | |
457 | sock_release(mappass->sock); | |
458 | flush_workqueue(mappass->wq); | |
459 | destroy_workqueue(mappass->wq); | |
460 | kfree(mappass); | |
461 | ||
b1efa693 SS |
462 | return 0; |
463 | } | |
464 | ||
465 | static int pvcalls_back_release(struct xenbus_device *dev, | |
466 | struct xen_pvcalls_request *req) | |
467 | { | |
a51729cb SS |
468 | struct pvcalls_fedata *fedata; |
469 | struct sock_mapping *map, *n; | |
470 | struct sockpass_mapping *mappass; | |
471 | int ret = 0; | |
472 | struct xen_pvcalls_response *rsp; | |
473 | ||
474 | fedata = dev_get_drvdata(&dev->dev); | |
475 | ||
476 | down(&fedata->socket_lock); | |
477 | list_for_each_entry_safe(map, n, &fedata->socket_mappings, list) { | |
478 | if (map->id == req->u.release.id) { | |
479 | list_del(&map->list); | |
480 | up(&fedata->socket_lock); | |
481 | ret = pvcalls_back_release_active(dev, fedata, map); | |
482 | goto out; | |
483 | } | |
484 | } | |
485 | mappass = radix_tree_lookup(&fedata->socketpass_mappings, | |
486 | req->u.release.id); | |
487 | if (mappass != NULL) { | |
488 | radix_tree_delete(&fedata->socketpass_mappings, mappass->id); | |
489 | up(&fedata->socket_lock); | |
490 | ret = pvcalls_back_release_passive(dev, fedata, mappass); | |
491 | } else | |
492 | up(&fedata->socket_lock); | |
493 | ||
494 | out: | |
495 | rsp = RING_GET_RESPONSE(&fedata->ring, fedata->ring.rsp_prod_pvt++); | |
496 | rsp->req_id = req->req_id; | |
497 | rsp->u.release.id = req->u.release.id; | |
498 | rsp->cmd = req->cmd; | |
499 | rsp->ret = ret; | |
b1efa693 SS |
500 | return 0; |
501 | } | |
502 | ||
331a63e6 SS |
503 | static void __pvcalls_back_accept(struct work_struct *work) |
504 | { | |
6f474e71 SS |
505 | struct sockpass_mapping *mappass = container_of( |
506 | work, struct sockpass_mapping, register_work); | |
507 | struct sock_mapping *map; | |
508 | struct pvcalls_ioworker *iow; | |
509 | struct pvcalls_fedata *fedata; | |
510 | struct socket *sock; | |
511 | struct xen_pvcalls_response *rsp; | |
512 | struct xen_pvcalls_request *req; | |
513 | int notify; | |
514 | int ret = -EINVAL; | |
515 | unsigned long flags; | |
516 | ||
517 | fedata = mappass->fedata; | |
518 | /* | |
519 | * __pvcalls_back_accept can race against pvcalls_back_accept. | |
520 | * We only need to check the value of "cmd" on read. It could be | |
521 | * done atomically, but to simplify the code on the write side, we | |
522 | * use a spinlock. | |
523 | */ | |
524 | spin_lock_irqsave(&mappass->copy_lock, flags); | |
525 | req = &mappass->reqcopy; | |
526 | if (req->cmd != PVCALLS_ACCEPT) { | |
527 | spin_unlock_irqrestore(&mappass->copy_lock, flags); | |
528 | return; | |
529 | } | |
530 | spin_unlock_irqrestore(&mappass->copy_lock, flags); | |
531 | ||
532 | sock = sock_alloc(); | |
533 | if (sock == NULL) | |
534 | goto out_error; | |
535 | sock->type = mappass->sock->type; | |
536 | sock->ops = mappass->sock->ops; | |
537 | ||
538 | ret = inet_accept(mappass->sock, sock, O_NONBLOCK, true); | |
539 | if (ret == -EAGAIN) { | |
540 | sock_release(sock); | |
76119125 | 541 | return; |
6f474e71 SS |
542 | } |
543 | ||
544 | map = pvcalls_new_active_socket(fedata, | |
545 | req->u.accept.id_new, | |
546 | req->u.accept.ref, | |
547 | req->u.accept.evtchn, | |
548 | sock); | |
549 | if (!map) { | |
550 | ret = -EFAULT; | |
551 | sock_release(sock); | |
552 | goto out_error; | |
553 | } | |
554 | ||
555 | map->sockpass = mappass; | |
556 | iow = &map->ioworker; | |
557 | atomic_inc(&map->read); | |
558 | atomic_inc(&map->io); | |
559 | queue_work(iow->wq, &iow->register_work); | |
560 | ||
561 | out_error: | |
562 | rsp = RING_GET_RESPONSE(&fedata->ring, fedata->ring.rsp_prod_pvt++); | |
563 | rsp->req_id = req->req_id; | |
564 | rsp->cmd = req->cmd; | |
565 | rsp->u.accept.id = req->u.accept.id; | |
566 | rsp->ret = ret; | |
567 | RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&fedata->ring, notify); | |
568 | if (notify) | |
569 | notify_remote_via_irq(fedata->irq); | |
570 | ||
571 | mappass->reqcopy.cmd = 0; | |
331a63e6 SS |
572 | } |
573 | ||
574 | static void pvcalls_pass_sk_data_ready(struct sock *sock) | |
575 | { | |
6f474e71 | 576 | struct sockpass_mapping *mappass = sock->sk_user_data; |
3cf33a58 SS |
577 | struct pvcalls_fedata *fedata; |
578 | struct xen_pvcalls_response *rsp; | |
579 | unsigned long flags; | |
580 | int notify; | |
6f474e71 SS |
581 | |
582 | if (mappass == NULL) | |
583 | return; | |
584 | ||
3cf33a58 SS |
585 | fedata = mappass->fedata; |
586 | spin_lock_irqsave(&mappass->copy_lock, flags); | |
587 | if (mappass->reqcopy.cmd == PVCALLS_POLL) { | |
588 | rsp = RING_GET_RESPONSE(&fedata->ring, | |
589 | fedata->ring.rsp_prod_pvt++); | |
590 | rsp->req_id = mappass->reqcopy.req_id; | |
591 | rsp->u.poll.id = mappass->reqcopy.u.poll.id; | |
592 | rsp->cmd = mappass->reqcopy.cmd; | |
593 | rsp->ret = 0; | |
594 | ||
595 | mappass->reqcopy.cmd = 0; | |
596 | spin_unlock_irqrestore(&mappass->copy_lock, flags); | |
597 | ||
598 | RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&fedata->ring, notify); | |
599 | if (notify) | |
600 | notify_remote_via_irq(mappass->fedata->irq); | |
601 | } else { | |
602 | spin_unlock_irqrestore(&mappass->copy_lock, flags); | |
603 | queue_work(mappass->wq, &mappass->register_work); | |
604 | } | |
331a63e6 SS |
605 | } |
606 | ||
b1efa693 SS |
607 | static int pvcalls_back_bind(struct xenbus_device *dev, |
608 | struct xen_pvcalls_request *req) | |
609 | { | |
331a63e6 SS |
610 | struct pvcalls_fedata *fedata; |
611 | int ret; | |
612 | struct sockpass_mapping *map; | |
613 | struct xen_pvcalls_response *rsp; | |
614 | ||
615 | fedata = dev_get_drvdata(&dev->dev); | |
616 | ||
617 | map = kzalloc(sizeof(*map), GFP_KERNEL); | |
618 | if (map == NULL) { | |
619 | ret = -ENOMEM; | |
620 | goto out; | |
621 | } | |
622 | ||
623 | INIT_WORK(&map->register_work, __pvcalls_back_accept); | |
624 | spin_lock_init(&map->copy_lock); | |
625 | map->wq = alloc_workqueue("pvcalls_wq", WQ_UNBOUND, 1); | |
626 | if (!map->wq) { | |
627 | ret = -ENOMEM; | |
628 | goto out; | |
629 | } | |
630 | ||
631 | ret = sock_create(AF_INET, SOCK_STREAM, 0, &map->sock); | |
632 | if (ret < 0) | |
633 | goto out; | |
634 | ||
635 | ret = inet_bind(map->sock, (struct sockaddr *)&req->u.bind.addr, | |
636 | req->u.bind.len); | |
637 | if (ret < 0) | |
638 | goto out; | |
639 | ||
640 | map->fedata = fedata; | |
641 | map->id = req->u.bind.id; | |
642 | ||
643 | down(&fedata->socket_lock); | |
644 | ret = radix_tree_insert(&fedata->socketpass_mappings, map->id, | |
645 | map); | |
646 | up(&fedata->socket_lock); | |
647 | if (ret) | |
648 | goto out; | |
649 | ||
650 | write_lock_bh(&map->sock->sk->sk_callback_lock); | |
651 | map->saved_data_ready = map->sock->sk->sk_data_ready; | |
652 | map->sock->sk->sk_user_data = map; | |
653 | map->sock->sk->sk_data_ready = pvcalls_pass_sk_data_ready; | |
654 | write_unlock_bh(&map->sock->sk->sk_callback_lock); | |
655 | ||
656 | out: | |
657 | if (ret) { | |
658 | if (map && map->sock) | |
659 | sock_release(map->sock); | |
660 | if (map && map->wq) | |
661 | destroy_workqueue(map->wq); | |
662 | kfree(map); | |
663 | } | |
664 | rsp = RING_GET_RESPONSE(&fedata->ring, fedata->ring.rsp_prod_pvt++); | |
665 | rsp->req_id = req->req_id; | |
666 | rsp->cmd = req->cmd; | |
667 | rsp->u.bind.id = req->u.bind.id; | |
668 | rsp->ret = ret; | |
b1efa693 SS |
669 | return 0; |
670 | } | |
671 | ||
672 | static int pvcalls_back_listen(struct xenbus_device *dev, | |
673 | struct xen_pvcalls_request *req) | |
674 | { | |
8ce3f762 SS |
675 | struct pvcalls_fedata *fedata; |
676 | int ret = -EINVAL; | |
677 | struct sockpass_mapping *map; | |
678 | struct xen_pvcalls_response *rsp; | |
679 | ||
680 | fedata = dev_get_drvdata(&dev->dev); | |
681 | ||
682 | down(&fedata->socket_lock); | |
683 | map = radix_tree_lookup(&fedata->socketpass_mappings, req->u.listen.id); | |
684 | up(&fedata->socket_lock); | |
685 | if (map == NULL) | |
686 | goto out; | |
687 | ||
688 | ret = inet_listen(map->sock, req->u.listen.backlog); | |
689 | ||
690 | out: | |
691 | rsp = RING_GET_RESPONSE(&fedata->ring, fedata->ring.rsp_prod_pvt++); | |
692 | rsp->req_id = req->req_id; | |
693 | rsp->cmd = req->cmd; | |
694 | rsp->u.listen.id = req->u.listen.id; | |
695 | rsp->ret = ret; | |
b1efa693 SS |
696 | return 0; |
697 | } | |
698 | ||
699 | static int pvcalls_back_accept(struct xenbus_device *dev, | |
700 | struct xen_pvcalls_request *req) | |
701 | { | |
6f474e71 SS |
702 | struct pvcalls_fedata *fedata; |
703 | struct sockpass_mapping *mappass; | |
704 | int ret = -EINVAL; | |
705 | struct xen_pvcalls_response *rsp; | |
706 | unsigned long flags; | |
707 | ||
708 | fedata = dev_get_drvdata(&dev->dev); | |
709 | ||
710 | down(&fedata->socket_lock); | |
711 | mappass = radix_tree_lookup(&fedata->socketpass_mappings, | |
712 | req->u.accept.id); | |
713 | up(&fedata->socket_lock); | |
714 | if (mappass == NULL) | |
715 | goto out_error; | |
716 | ||
717 | /* | |
718 | * Limitation of the current implementation: only support one | |
719 | * concurrent accept or poll call on one socket. | |
720 | */ | |
721 | spin_lock_irqsave(&mappass->copy_lock, flags); | |
722 | if (mappass->reqcopy.cmd != 0) { | |
723 | spin_unlock_irqrestore(&mappass->copy_lock, flags); | |
724 | ret = -EINTR; | |
725 | goto out_error; | |
726 | } | |
727 | ||
728 | mappass->reqcopy = *req; | |
729 | spin_unlock_irqrestore(&mappass->copy_lock, flags); | |
730 | queue_work(mappass->wq, &mappass->register_work); | |
731 | ||
732 | /* Tell the caller we don't need to send back a notification yet */ | |
733 | return -1; | |
734 | ||
735 | out_error: | |
736 | rsp = RING_GET_RESPONSE(&fedata->ring, fedata->ring.rsp_prod_pvt++); | |
737 | rsp->req_id = req->req_id; | |
738 | rsp->cmd = req->cmd; | |
739 | rsp->u.accept.id = req->u.accept.id; | |
740 | rsp->ret = ret; | |
b1efa693 SS |
741 | return 0; |
742 | } | |
743 | ||
744 | static int pvcalls_back_poll(struct xenbus_device *dev, | |
745 | struct xen_pvcalls_request *req) | |
746 | { | |
3cf33a58 SS |
747 | struct pvcalls_fedata *fedata; |
748 | struct sockpass_mapping *mappass; | |
749 | struct xen_pvcalls_response *rsp; | |
750 | struct inet_connection_sock *icsk; | |
751 | struct request_sock_queue *queue; | |
752 | unsigned long flags; | |
753 | int ret; | |
754 | bool data; | |
755 | ||
756 | fedata = dev_get_drvdata(&dev->dev); | |
757 | ||
758 | down(&fedata->socket_lock); | |
759 | mappass = radix_tree_lookup(&fedata->socketpass_mappings, | |
760 | req->u.poll.id); | |
761 | up(&fedata->socket_lock); | |
762 | if (mappass == NULL) | |
763 | return -EINVAL; | |
764 | ||
765 | /* | |
766 | * Limitation of the current implementation: only support one | |
767 | * concurrent accept or poll call on one socket. | |
768 | */ | |
769 | spin_lock_irqsave(&mappass->copy_lock, flags); | |
770 | if (mappass->reqcopy.cmd != 0) { | |
771 | ret = -EINTR; | |
772 | goto out; | |
773 | } | |
774 | ||
775 | mappass->reqcopy = *req; | |
776 | icsk = inet_csk(mappass->sock->sk); | |
777 | queue = &icsk->icsk_accept_queue; | |
778 | data = queue->rskq_accept_head != NULL; | |
779 | if (data) { | |
780 | mappass->reqcopy.cmd = 0; | |
781 | ret = 0; | |
782 | goto out; | |
783 | } | |
784 | spin_unlock_irqrestore(&mappass->copy_lock, flags); | |
785 | ||
786 | /* Tell the caller we don't need to send back a notification yet */ | |
787 | return -1; | |
788 | ||
789 | out: | |
790 | spin_unlock_irqrestore(&mappass->copy_lock, flags); | |
791 | ||
792 | rsp = RING_GET_RESPONSE(&fedata->ring, fedata->ring.rsp_prod_pvt++); | |
793 | rsp->req_id = req->req_id; | |
794 | rsp->cmd = req->cmd; | |
795 | rsp->u.poll.id = req->u.poll.id; | |
796 | rsp->ret = ret; | |
b1efa693 SS |
797 | return 0; |
798 | } | |
799 | ||
800 | static int pvcalls_back_handle_cmd(struct xenbus_device *dev, | |
801 | struct xen_pvcalls_request *req) | |
802 | { | |
803 | int ret = 0; | |
804 | ||
805 | switch (req->cmd) { | |
806 | case PVCALLS_SOCKET: | |
807 | ret = pvcalls_back_socket(dev, req); | |
808 | break; | |
809 | case PVCALLS_CONNECT: | |
810 | ret = pvcalls_back_connect(dev, req); | |
811 | break; | |
812 | case PVCALLS_RELEASE: | |
813 | ret = pvcalls_back_release(dev, req); | |
814 | break; | |
815 | case PVCALLS_BIND: | |
816 | ret = pvcalls_back_bind(dev, req); | |
817 | break; | |
818 | case PVCALLS_LISTEN: | |
819 | ret = pvcalls_back_listen(dev, req); | |
820 | break; | |
821 | case PVCALLS_ACCEPT: | |
822 | ret = pvcalls_back_accept(dev, req); | |
823 | break; | |
824 | case PVCALLS_POLL: | |
825 | ret = pvcalls_back_poll(dev, req); | |
826 | break; | |
827 | default: | |
828 | { | |
829 | struct pvcalls_fedata *fedata; | |
830 | struct xen_pvcalls_response *rsp; | |
831 | ||
832 | fedata = dev_get_drvdata(&dev->dev); | |
833 | rsp = RING_GET_RESPONSE( | |
834 | &fedata->ring, fedata->ring.rsp_prod_pvt++); | |
835 | rsp->req_id = req->req_id; | |
836 | rsp->cmd = req->cmd; | |
837 | rsp->ret = -ENOTSUPP; | |
838 | break; | |
839 | } | |
840 | } | |
841 | return ret; | |
842 | } | |
843 | ||
844 | static void pvcalls_back_work(struct pvcalls_fedata *fedata) | |
845 | { | |
846 | int notify, notify_all = 0, more = 1; | |
847 | struct xen_pvcalls_request req; | |
848 | struct xenbus_device *dev = fedata->dev; | |
849 | ||
850 | while (more) { | |
851 | while (RING_HAS_UNCONSUMED_REQUESTS(&fedata->ring)) { | |
852 | RING_COPY_REQUEST(&fedata->ring, | |
853 | fedata->ring.req_cons++, | |
854 | &req); | |
855 | ||
856 | if (!pvcalls_back_handle_cmd(dev, &req)) { | |
857 | RING_PUSH_RESPONSES_AND_CHECK_NOTIFY( | |
858 | &fedata->ring, notify); | |
859 | notify_all += notify; | |
860 | } | |
861 | } | |
862 | ||
863 | if (notify_all) { | |
864 | notify_remote_via_irq(fedata->irq); | |
865 | notify_all = 0; | |
866 | } | |
867 | ||
868 | RING_FINAL_CHECK_FOR_REQUESTS(&fedata->ring, more); | |
869 | } | |
870 | } | |
871 | ||
d0e4d560 SS |
872 | static irqreturn_t pvcalls_back_event(int irq, void *dev_id) |
873 | { | |
b1efa693 SS |
874 | struct xenbus_device *dev = dev_id; |
875 | struct pvcalls_fedata *fedata = NULL; | |
876 | ||
877 | if (dev == NULL) | |
878 | return IRQ_HANDLED; | |
879 | ||
880 | fedata = dev_get_drvdata(&dev->dev); | |
881 | if (fedata == NULL) | |
882 | return IRQ_HANDLED; | |
883 | ||
884 | pvcalls_back_work(fedata); | |
d0e4d560 SS |
885 | return IRQ_HANDLED; |
886 | } | |
887 | ||
5db4d286 SS |
888 | static irqreturn_t pvcalls_back_conn_event(int irq, void *sock_map) |
889 | { | |
5ad9918f SS |
890 | struct sock_mapping *map = sock_map; |
891 | struct pvcalls_ioworker *iow; | |
892 | ||
893 | if (map == NULL || map->sock == NULL || map->sock->sk == NULL || | |
894 | map->sock->sk->sk_user_data != map) | |
895 | return IRQ_HANDLED; | |
896 | ||
897 | iow = &map->ioworker; | |
898 | ||
899 | atomic_inc(&map->write); | |
900 | atomic_inc(&map->io); | |
901 | queue_work(iow->wq, &iow->register_work); | |
902 | ||
5db4d286 SS |
903 | return IRQ_HANDLED; |
904 | } | |
905 | ||
0a9c75c2 SS |
906 | static int backend_connect(struct xenbus_device *dev) |
907 | { | |
d0e4d560 SS |
908 | int err, evtchn; |
909 | grant_ref_t ring_ref; | |
910 | struct pvcalls_fedata *fedata = NULL; | |
911 | ||
912 | fedata = kzalloc(sizeof(struct pvcalls_fedata), GFP_KERNEL); | |
913 | if (!fedata) | |
914 | return -ENOMEM; | |
915 | ||
916 | fedata->irq = -1; | |
917 | err = xenbus_scanf(XBT_NIL, dev->otherend, "port", "%u", | |
918 | &evtchn); | |
919 | if (err != 1) { | |
920 | err = -EINVAL; | |
921 | xenbus_dev_fatal(dev, err, "reading %s/event-channel", | |
922 | dev->otherend); | |
923 | goto error; | |
924 | } | |
925 | ||
926 | err = xenbus_scanf(XBT_NIL, dev->otherend, "ring-ref", "%u", &ring_ref); | |
927 | if (err != 1) { | |
928 | err = -EINVAL; | |
929 | xenbus_dev_fatal(dev, err, "reading %s/ring-ref", | |
930 | dev->otherend); | |
931 | goto error; | |
932 | } | |
933 | ||
934 | err = bind_interdomain_evtchn_to_irq(dev->otherend_id, evtchn); | |
935 | if (err < 0) | |
936 | goto error; | |
937 | fedata->irq = err; | |
938 | ||
939 | err = request_threaded_irq(fedata->irq, NULL, pvcalls_back_event, | |
940 | IRQF_ONESHOT, "pvcalls-back", dev); | |
941 | if (err < 0) | |
942 | goto error; | |
943 | ||
944 | err = xenbus_map_ring_valloc(dev, &ring_ref, 1, | |
945 | (void **)&fedata->sring); | |
946 | if (err < 0) | |
947 | goto error; | |
948 | ||
949 | BACK_RING_INIT(&fedata->ring, fedata->sring, XEN_PAGE_SIZE * 1); | |
950 | fedata->dev = dev; | |
951 | ||
952 | INIT_LIST_HEAD(&fedata->socket_mappings); | |
953 | INIT_RADIX_TREE(&fedata->socketpass_mappings, GFP_KERNEL); | |
954 | sema_init(&fedata->socket_lock, 1); | |
955 | dev_set_drvdata(&dev->dev, fedata); | |
956 | ||
957 | down(&pvcalls_back_global.frontends_lock); | |
958 | list_add_tail(&fedata->list, &pvcalls_back_global.frontends); | |
959 | up(&pvcalls_back_global.frontends_lock); | |
960 | ||
0a9c75c2 | 961 | return 0; |
d0e4d560 SS |
962 | |
963 | error: | |
964 | if (fedata->irq >= 0) | |
965 | unbind_from_irqhandler(fedata->irq, dev); | |
966 | if (fedata->sring != NULL) | |
967 | xenbus_unmap_ring_vfree(dev, fedata->sring); | |
968 | kfree(fedata); | |
969 | return err; | |
0a9c75c2 SS |
970 | } |
971 | ||
972 | static int backend_disconnect(struct xenbus_device *dev) | |
973 | { | |
0a85d23b SS |
974 | struct pvcalls_fedata *fedata; |
975 | struct sock_mapping *map, *n; | |
976 | struct sockpass_mapping *mappass; | |
977 | struct radix_tree_iter iter; | |
978 | void **slot; | |
979 | ||
980 | ||
981 | fedata = dev_get_drvdata(&dev->dev); | |
982 | ||
983 | down(&fedata->socket_lock); | |
984 | list_for_each_entry_safe(map, n, &fedata->socket_mappings, list) { | |
985 | list_del(&map->list); | |
986 | pvcalls_back_release_active(dev, fedata, map); | |
987 | } | |
988 | ||
989 | radix_tree_for_each_slot(slot, &fedata->socketpass_mappings, &iter, 0) { | |
990 | mappass = radix_tree_deref_slot(slot); | |
991 | if (!mappass) | |
992 | continue; | |
993 | if (radix_tree_exception(mappass)) { | |
994 | if (radix_tree_deref_retry(mappass)) | |
995 | slot = radix_tree_iter_retry(&iter); | |
996 | } else { | |
997 | radix_tree_delete(&fedata->socketpass_mappings, | |
998 | mappass->id); | |
999 | pvcalls_back_release_passive(dev, fedata, mappass); | |
1000 | } | |
1001 | } | |
1002 | up(&fedata->socket_lock); | |
1003 | ||
1004 | unbind_from_irqhandler(fedata->irq, dev); | |
1005 | xenbus_unmap_ring_vfree(dev, fedata->sring); | |
1006 | ||
1007 | list_del(&fedata->list); | |
1008 | kfree(fedata); | |
1009 | dev_set_drvdata(&dev->dev, NULL); | |
1010 | ||
0a9c75c2 SS |
1011 | return 0; |
1012 | } | |
1013 | ||
72e59c30 SS |
1014 | static int pvcalls_back_probe(struct xenbus_device *dev, |
1015 | const struct xenbus_device_id *id) | |
1016 | { | |
0a9c75c2 SS |
1017 | int err, abort; |
1018 | struct xenbus_transaction xbt; | |
1019 | ||
1020 | again: | |
1021 | abort = 1; | |
1022 | ||
1023 | err = xenbus_transaction_start(&xbt); | |
1024 | if (err) { | |
1025 | pr_warn("%s cannot create xenstore transaction\n", __func__); | |
1026 | return err; | |
1027 | } | |
1028 | ||
1029 | err = xenbus_printf(xbt, dev->nodename, "versions", "%s", | |
1030 | PVCALLS_VERSIONS); | |
1031 | if (err) { | |
1032 | pr_warn("%s write out 'versions' failed\n", __func__); | |
1033 | goto abort; | |
1034 | } | |
1035 | ||
1036 | err = xenbus_printf(xbt, dev->nodename, "max-page-order", "%u", | |
1037 | MAX_RING_ORDER); | |
1038 | if (err) { | |
1039 | pr_warn("%s write out 'max-page-order' failed\n", __func__); | |
1040 | goto abort; | |
1041 | } | |
1042 | ||
1043 | err = xenbus_printf(xbt, dev->nodename, "function-calls", | |
1044 | XENBUS_FUNCTIONS_CALLS); | |
1045 | if (err) { | |
1046 | pr_warn("%s write out 'function-calls' failed\n", __func__); | |
1047 | goto abort; | |
1048 | } | |
1049 | ||
1050 | abort = 0; | |
1051 | abort: | |
1052 | err = xenbus_transaction_end(xbt, abort); | |
1053 | if (err) { | |
1054 | if (err == -EAGAIN && !abort) | |
1055 | goto again; | |
1056 | pr_warn("%s cannot complete xenstore transaction\n", __func__); | |
1057 | return err; | |
1058 | } | |
1059 | ||
1060 | if (abort) | |
1061 | return -EFAULT; | |
1062 | ||
1063 | xenbus_switch_state(dev, XenbusStateInitWait); | |
1064 | ||
72e59c30 SS |
1065 | return 0; |
1066 | } | |
1067 | ||
0a9c75c2 SS |
1068 | static void set_backend_state(struct xenbus_device *dev, |
1069 | enum xenbus_state state) | |
1070 | { | |
1071 | while (dev->state != state) { | |
1072 | switch (dev->state) { | |
1073 | case XenbusStateClosed: | |
1074 | switch (state) { | |
1075 | case XenbusStateInitWait: | |
1076 | case XenbusStateConnected: | |
1077 | xenbus_switch_state(dev, XenbusStateInitWait); | |
1078 | break; | |
1079 | case XenbusStateClosing: | |
1080 | xenbus_switch_state(dev, XenbusStateClosing); | |
1081 | break; | |
1082 | default: | |
fefcfb99 | 1083 | WARN_ON(1); |
0a9c75c2 SS |
1084 | } |
1085 | break; | |
1086 | case XenbusStateInitWait: | |
1087 | case XenbusStateInitialised: | |
1088 | switch (state) { | |
1089 | case XenbusStateConnected: | |
1090 | backend_connect(dev); | |
1091 | xenbus_switch_state(dev, XenbusStateConnected); | |
1092 | break; | |
1093 | case XenbusStateClosing: | |
1094 | case XenbusStateClosed: | |
1095 | xenbus_switch_state(dev, XenbusStateClosing); | |
1096 | break; | |
1097 | default: | |
fefcfb99 | 1098 | WARN_ON(1); |
0a9c75c2 SS |
1099 | } |
1100 | break; | |
1101 | case XenbusStateConnected: | |
1102 | switch (state) { | |
1103 | case XenbusStateInitWait: | |
1104 | case XenbusStateClosing: | |
1105 | case XenbusStateClosed: | |
1106 | down(&pvcalls_back_global.frontends_lock); | |
1107 | backend_disconnect(dev); | |
1108 | up(&pvcalls_back_global.frontends_lock); | |
1109 | xenbus_switch_state(dev, XenbusStateClosing); | |
1110 | break; | |
1111 | default: | |
fefcfb99 | 1112 | WARN_ON(1); |
0a9c75c2 SS |
1113 | } |
1114 | break; | |
1115 | case XenbusStateClosing: | |
1116 | switch (state) { | |
1117 | case XenbusStateInitWait: | |
1118 | case XenbusStateConnected: | |
1119 | case XenbusStateClosed: | |
1120 | xenbus_switch_state(dev, XenbusStateClosed); | |
1121 | break; | |
1122 | default: | |
fefcfb99 | 1123 | WARN_ON(1); |
0a9c75c2 SS |
1124 | } |
1125 | break; | |
1126 | default: | |
fefcfb99 | 1127 | WARN_ON(1); |
0a9c75c2 SS |
1128 | } |
1129 | } | |
1130 | } | |
1131 | ||
72e59c30 SS |
1132 | static void pvcalls_back_changed(struct xenbus_device *dev, |
1133 | enum xenbus_state frontend_state) | |
1134 | { | |
0a9c75c2 SS |
1135 | switch (frontend_state) { |
1136 | case XenbusStateInitialising: | |
1137 | set_backend_state(dev, XenbusStateInitWait); | |
1138 | break; | |
1139 | ||
1140 | case XenbusStateInitialised: | |
1141 | case XenbusStateConnected: | |
1142 | set_backend_state(dev, XenbusStateConnected); | |
1143 | break; | |
1144 | ||
1145 | case XenbusStateClosing: | |
1146 | set_backend_state(dev, XenbusStateClosing); | |
1147 | break; | |
1148 | ||
1149 | case XenbusStateClosed: | |
1150 | set_backend_state(dev, XenbusStateClosed); | |
1151 | if (xenbus_dev_is_online(dev)) | |
1152 | break; | |
1153 | device_unregister(&dev->dev); | |
1154 | break; | |
1155 | case XenbusStateUnknown: | |
1156 | set_backend_state(dev, XenbusStateClosed); | |
1157 | device_unregister(&dev->dev); | |
1158 | break; | |
1159 | ||
1160 | default: | |
1161 | xenbus_dev_fatal(dev, -EINVAL, "saw state %d at frontend", | |
1162 | frontend_state); | |
1163 | break; | |
1164 | } | |
72e59c30 SS |
1165 | } |
1166 | ||
1167 | static int pvcalls_back_remove(struct xenbus_device *dev) | |
1168 | { | |
1169 | return 0; | |
1170 | } | |
1171 | ||
1172 | static int pvcalls_back_uevent(struct xenbus_device *xdev, | |
1173 | struct kobj_uevent_env *env) | |
1174 | { | |
1175 | return 0; | |
1176 | } | |
1177 | ||
1178 | static const struct xenbus_device_id pvcalls_back_ids[] = { | |
1179 | { "pvcalls" }, | |
1180 | { "" } | |
1181 | }; | |
1182 | ||
1183 | static struct xenbus_driver pvcalls_back_driver = { | |
1184 | .ids = pvcalls_back_ids, | |
1185 | .probe = pvcalls_back_probe, | |
1186 | .remove = pvcalls_back_remove, | |
1187 | .uevent = pvcalls_back_uevent, | |
1188 | .otherend_changed = pvcalls_back_changed, | |
1189 | }; | |
9be07334 SS |
1190 | |
1191 | static int __init pvcalls_back_init(void) | |
1192 | { | |
1193 | int ret; | |
1194 | ||
1195 | if (!xen_domain()) | |
1196 | return -ENODEV; | |
1197 | ||
1198 | ret = xenbus_register_backend(&pvcalls_back_driver); | |
1199 | if (ret < 0) | |
1200 | return ret; | |
1201 | ||
1202 | sema_init(&pvcalls_back_global.frontends_lock, 1); | |
1203 | INIT_LIST_HEAD(&pvcalls_back_global.frontends); | |
1204 | return 0; | |
1205 | } | |
1206 | module_init(pvcalls_back_init); | |
0a85d23b SS |
1207 | |
1208 | static void __exit pvcalls_back_fin(void) | |
1209 | { | |
1210 | struct pvcalls_fedata *fedata, *nfedata; | |
1211 | ||
1212 | down(&pvcalls_back_global.frontends_lock); | |
1213 | list_for_each_entry_safe(fedata, nfedata, | |
1214 | &pvcalls_back_global.frontends, list) { | |
1215 | backend_disconnect(fedata->dev); | |
1216 | } | |
1217 | up(&pvcalls_back_global.frontends_lock); | |
1218 | ||
1219 | xenbus_unregister_driver(&pvcalls_back_driver); | |
1220 | } | |
1221 | ||
1222 | module_exit(pvcalls_back_fin); | |
24e7f84d BO |
1223 | |
1224 | MODULE_DESCRIPTION("Xen PV Calls backend driver"); | |
1225 | MODULE_AUTHOR("Stefano Stabellini <sstabellini@kernel.org>"); | |
1226 | MODULE_LICENSE("GPL"); |