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bcabbcca OBC |
1 | /* |
2 | * Virtio-based remote processor messaging bus | |
3 | * | |
4 | * Copyright (C) 2011 Texas Instruments, Inc. | |
5 | * Copyright (C) 2011 Google, Inc. | |
6 | * | |
7 | * Ohad Ben-Cohen <ohad@wizery.com> | |
8 | * Brian Swetland <swetland@google.com> | |
9 | * | |
10 | * This software is licensed under the terms of the GNU General Public | |
11 | * License version 2, as published by the Free Software Foundation, and | |
12 | * may be copied, distributed, and modified under those terms. | |
13 | * | |
14 | * This program is distributed in the hope that it will be useful, | |
15 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
16 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
17 | * GNU General Public License for more details. | |
18 | */ | |
19 | ||
20 | #define pr_fmt(fmt) "%s: " fmt, __func__ | |
21 | ||
22 | #include <linux/kernel.h> | |
23 | #include <linux/module.h> | |
24 | #include <linux/virtio.h> | |
25 | #include <linux/virtio_ids.h> | |
26 | #include <linux/virtio_config.h> | |
27 | #include <linux/scatterlist.h> | |
28 | #include <linux/dma-mapping.h> | |
29 | #include <linux/slab.h> | |
30 | #include <linux/idr.h> | |
31 | #include <linux/jiffies.h> | |
32 | #include <linux/sched.h> | |
33 | #include <linux/wait.h> | |
34 | #include <linux/rpmsg.h> | |
35 | #include <linux/mutex.h> | |
a16644cb | 36 | #include <linux/of_device.h> |
bcabbcca | 37 | |
8b881c07 BA |
38 | #include "rpmsg_internal.h" |
39 | ||
bcabbcca OBC |
40 | /** |
41 | * struct virtproc_info - virtual remote processor state | |
42 | * @vdev: the virtio device | |
43 | * @rvq: rx virtqueue | |
44 | * @svq: tx virtqueue | |
45 | * @rbufs: kernel address of rx buffers | |
46 | * @sbufs: kernel address of tx buffers | |
b1b98914 | 47 | * @num_bufs: total number of buffers for rx and tx |
bcabbcca OBC |
48 | * @last_sbuf: index of last tx buffer used |
49 | * @bufs_dma: dma base addr of the buffers | |
50 | * @tx_lock: protects svq, sbufs and sleepers, to allow concurrent senders. | |
51 | * sending a message might require waking up a dozing remote | |
52 | * processor, which involves sleeping, hence the mutex. | |
53 | * @endpoints: idr of local endpoints, allows fast retrieval | |
54 | * @endpoints_lock: lock of the endpoints set | |
55 | * @sendq: wait queue of sending contexts waiting for a tx buffers | |
56 | * @sleepers: number of senders that are waiting for a tx buffer | |
57 | * @ns_ept: the bus's name service endpoint | |
58 | * | |
59 | * This structure stores the rpmsg state of a given virtio remote processor | |
60 | * device (there might be several virtio proc devices for each physical | |
61 | * remote processor). | |
62 | */ | |
63 | struct virtproc_info { | |
64 | struct virtio_device *vdev; | |
65 | struct virtqueue *rvq, *svq; | |
66 | void *rbufs, *sbufs; | |
b1b98914 | 67 | unsigned int num_bufs; |
bcabbcca OBC |
68 | int last_sbuf; |
69 | dma_addr_t bufs_dma; | |
70 | struct mutex tx_lock; | |
71 | struct idr endpoints; | |
72 | struct mutex endpoints_lock; | |
73 | wait_queue_head_t sendq; | |
74 | atomic_t sleepers; | |
75 | struct rpmsg_endpoint *ns_ept; | |
76 | }; | |
77 | ||
e88dae5d BA |
78 | /* The feature bitmap for virtio rpmsg */ |
79 | #define VIRTIO_RPMSG_F_NS 0 /* RP supports name service notifications */ | |
80 | ||
81 | /** | |
82 | * struct rpmsg_hdr - common header for all rpmsg messages | |
83 | * @src: source address | |
84 | * @dst: destination address | |
85 | * @reserved: reserved for future use | |
86 | * @len: length of payload (in bytes) | |
87 | * @flags: message flags | |
88 | * @data: @len bytes of message payload data | |
89 | * | |
90 | * Every message sent(/received) on the rpmsg bus begins with this header. | |
91 | */ | |
92 | struct rpmsg_hdr { | |
93 | u32 src; | |
94 | u32 dst; | |
95 | u32 reserved; | |
96 | u16 len; | |
97 | u16 flags; | |
98 | u8 data[0]; | |
99 | } __packed; | |
100 | ||
101 | /** | |
102 | * struct rpmsg_ns_msg - dynamic name service announcement message | |
103 | * @name: name of remote service that is published | |
104 | * @addr: address of remote service that is published | |
105 | * @flags: indicates whether service is created or destroyed | |
106 | * | |
107 | * This message is sent across to publish a new service, or announce | |
108 | * about its removal. When we receive these messages, an appropriate | |
109 | * rpmsg channel (i.e device) is created/destroyed. In turn, the ->probe() | |
110 | * or ->remove() handler of the appropriate rpmsg driver will be invoked | |
111 | * (if/as-soon-as one is registered). | |
112 | */ | |
113 | struct rpmsg_ns_msg { | |
114 | char name[RPMSG_NAME_SIZE]; | |
115 | u32 addr; | |
116 | u32 flags; | |
117 | } __packed; | |
118 | ||
119 | /** | |
120 | * enum rpmsg_ns_flags - dynamic name service announcement flags | |
121 | * | |
122 | * @RPMSG_NS_CREATE: a new remote service was just created | |
123 | * @RPMSG_NS_DESTROY: a known remote service was just destroyed | |
124 | */ | |
125 | enum rpmsg_ns_flags { | |
126 | RPMSG_NS_CREATE = 0, | |
127 | RPMSG_NS_DESTROY = 1, | |
128 | }; | |
129 | ||
3bf950ff BA |
130 | /** |
131 | * @vrp: the remote processor this channel belongs to | |
132 | */ | |
133 | struct virtio_rpmsg_channel { | |
134 | struct rpmsg_device rpdev; | |
135 | ||
136 | struct virtproc_info *vrp; | |
137 | }; | |
138 | ||
139 | #define to_virtio_rpmsg_channel(_rpdev) \ | |
140 | container_of(_rpdev, struct virtio_rpmsg_channel, rpdev) | |
141 | ||
bcabbcca | 142 | /* |
b1b98914 SA |
143 | * We're allocating buffers of 512 bytes each for communications. The |
144 | * number of buffers will be computed from the number of buffers supported | |
145 | * by the vring, upto a maximum of 512 buffers (256 in each direction). | |
bcabbcca OBC |
146 | * |
147 | * Each buffer will have 16 bytes for the msg header and 496 bytes for | |
148 | * the payload. | |
149 | * | |
b1b98914 | 150 | * This will utilize a maximum total space of 256KB for the buffers. |
bcabbcca OBC |
151 | * |
152 | * We might also want to add support for user-provided buffers in time. | |
153 | * This will allow bigger buffer size flexibility, and can also be used | |
154 | * to achieve zero-copy messaging. | |
155 | * | |
156 | * Note that these numbers are purely a decision of this driver - we | |
157 | * can change this without changing anything in the firmware of the remote | |
158 | * processor. | |
159 | */ | |
b1b98914 | 160 | #define MAX_RPMSG_NUM_BUFS (512) |
bcabbcca | 161 | #define RPMSG_BUF_SIZE (512) |
bcabbcca OBC |
162 | |
163 | /* | |
164 | * Local addresses are dynamically allocated on-demand. | |
165 | * We do not dynamically assign addresses from the low 1024 range, | |
166 | * in order to reserve that address range for predefined services. | |
167 | */ | |
168 | #define RPMSG_RESERVED_ADDRESSES (1024) | |
169 | ||
170 | /* Address 53 is reserved for advertising remote services */ | |
171 | #define RPMSG_NS_ADDR (53) | |
172 | ||
8a228ecf BA |
173 | static void virtio_rpmsg_destroy_ept(struct rpmsg_endpoint *ept); |
174 | static int virtio_rpmsg_send(struct rpmsg_endpoint *ept, void *data, int len); | |
175 | static int virtio_rpmsg_sendto(struct rpmsg_endpoint *ept, void *data, int len, | |
176 | u32 dst); | |
177 | static int virtio_rpmsg_send_offchannel(struct rpmsg_endpoint *ept, u32 src, | |
178 | u32 dst, void *data, int len); | |
179 | static int virtio_rpmsg_trysend(struct rpmsg_endpoint *ept, void *data, int len); | |
180 | static int virtio_rpmsg_trysendto(struct rpmsg_endpoint *ept, void *data, | |
181 | int len, u32 dst); | |
182 | static int virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, | |
183 | u32 dst, void *data, int len); | |
bcabbcca | 184 | |
8a228ecf BA |
185 | static const struct rpmsg_endpoint_ops virtio_endpoint_ops = { |
186 | .destroy_ept = virtio_rpmsg_destroy_ept, | |
187 | .send = virtio_rpmsg_send, | |
188 | .sendto = virtio_rpmsg_sendto, | |
189 | .send_offchannel = virtio_rpmsg_send_offchannel, | |
190 | .trysend = virtio_rpmsg_trysend, | |
191 | .trysendto = virtio_rpmsg_trysendto, | |
192 | .trysend_offchannel = virtio_rpmsg_trysend_offchannel, | |
193 | }; | |
194 | ||
5a081caa OBC |
195 | /** |
196 | * __ept_release() - deallocate an rpmsg endpoint | |
197 | * @kref: the ept's reference count | |
198 | * | |
199 | * This function deallocates an ept, and is invoked when its @kref refcount | |
200 | * drops to zero. | |
201 | * | |
202 | * Never invoke this function directly! | |
203 | */ | |
204 | static void __ept_release(struct kref *kref) | |
205 | { | |
206 | struct rpmsg_endpoint *ept = container_of(kref, struct rpmsg_endpoint, | |
207 | refcount); | |
208 | /* | |
209 | * At this point no one holds a reference to ept anymore, | |
210 | * so we can directly free it | |
211 | */ | |
212 | kfree(ept); | |
213 | } | |
214 | ||
bcabbcca OBC |
215 | /* for more info, see below documentation of rpmsg_create_ept() */ |
216 | static struct rpmsg_endpoint *__rpmsg_create_ept(struct virtproc_info *vrp, | |
92e1de51 | 217 | struct rpmsg_device *rpdev, |
0963679c AS |
218 | rpmsg_rx_cb_t cb, |
219 | void *priv, u32 addr) | |
bcabbcca | 220 | { |
d0ffce77 | 221 | int id_min, id_max, id; |
bcabbcca OBC |
222 | struct rpmsg_endpoint *ept; |
223 | struct device *dev = rpdev ? &rpdev->dev : &vrp->vdev->dev; | |
224 | ||
bcabbcca | 225 | ept = kzalloc(sizeof(*ept), GFP_KERNEL); |
a8bb3fd9 | 226 | if (!ept) |
bcabbcca | 227 | return NULL; |
bcabbcca | 228 | |
5a081caa | 229 | kref_init(&ept->refcount); |
15fd943a | 230 | mutex_init(&ept->cb_lock); |
5a081caa | 231 | |
bcabbcca OBC |
232 | ept->rpdev = rpdev; |
233 | ept->cb = cb; | |
234 | ept->priv = priv; | |
8a228ecf | 235 | ept->ops = &virtio_endpoint_ops; |
bcabbcca OBC |
236 | |
237 | /* do we need to allocate a local address ? */ | |
d0ffce77 TH |
238 | if (addr == RPMSG_ADDR_ANY) { |
239 | id_min = RPMSG_RESERVED_ADDRESSES; | |
240 | id_max = 0; | |
241 | } else { | |
242 | id_min = addr; | |
243 | id_max = addr + 1; | |
244 | } | |
bcabbcca OBC |
245 | |
246 | mutex_lock(&vrp->endpoints_lock); | |
247 | ||
248 | /* bind the endpoint to an rpmsg address (and allocate one if needed) */ | |
d0ffce77 TH |
249 | id = idr_alloc(&vrp->endpoints, ept, id_min, id_max, GFP_KERNEL); |
250 | if (id < 0) { | |
251 | dev_err(dev, "idr_alloc failed: %d\n", id); | |
bcabbcca OBC |
252 | goto free_ept; |
253 | } | |
d0ffce77 | 254 | ept->addr = id; |
bcabbcca OBC |
255 | |
256 | mutex_unlock(&vrp->endpoints_lock); | |
257 | ||
258 | return ept; | |
259 | ||
bcabbcca OBC |
260 | free_ept: |
261 | mutex_unlock(&vrp->endpoints_lock); | |
5a081caa | 262 | kref_put(&ept->refcount, __ept_release); |
bcabbcca OBC |
263 | return NULL; |
264 | } | |
265 | ||
36b72c7d BA |
266 | static struct rpmsg_endpoint *virtio_rpmsg_create_ept(struct rpmsg_device *rpdev, |
267 | rpmsg_rx_cb_t cb, | |
268 | void *priv, | |
269 | struct rpmsg_channel_info chinfo) | |
270 | { | |
3bf950ff BA |
271 | struct virtio_rpmsg_channel *vch = to_virtio_rpmsg_channel(rpdev); |
272 | ||
273 | return __rpmsg_create_ept(vch->vrp, rpdev, cb, priv, chinfo.src); | |
36b72c7d BA |
274 | } |
275 | ||
bcabbcca | 276 | /** |
fa2d7795 OBC |
277 | * __rpmsg_destroy_ept() - destroy an existing rpmsg endpoint |
278 | * @vrp: virtproc which owns this ept | |
bcabbcca OBC |
279 | * @ept: endpoing to destroy |
280 | * | |
fa2d7795 OBC |
281 | * An internal function which destroy an ept without assuming it is |
282 | * bound to an rpmsg channel. This is needed for handling the internal | |
283 | * name service endpoint, which isn't bound to an rpmsg channel. | |
284 | * See also __rpmsg_create_ept(). | |
bcabbcca | 285 | */ |
fa2d7795 OBC |
286 | static void |
287 | __rpmsg_destroy_ept(struct virtproc_info *vrp, struct rpmsg_endpoint *ept) | |
bcabbcca | 288 | { |
15fd943a | 289 | /* make sure new inbound messages can't find this ept anymore */ |
bcabbcca OBC |
290 | mutex_lock(&vrp->endpoints_lock); |
291 | idr_remove(&vrp->endpoints, ept->addr); | |
292 | mutex_unlock(&vrp->endpoints_lock); | |
293 | ||
15fd943a OBC |
294 | /* make sure in-flight inbound messages won't invoke cb anymore */ |
295 | mutex_lock(&ept->cb_lock); | |
296 | ept->cb = NULL; | |
297 | mutex_unlock(&ept->cb_lock); | |
298 | ||
5a081caa | 299 | kref_put(&ept->refcount, __ept_release); |
bcabbcca | 300 | } |
fa2d7795 | 301 | |
8a228ecf BA |
302 | static void virtio_rpmsg_destroy_ept(struct rpmsg_endpoint *ept) |
303 | { | |
3bf950ff BA |
304 | struct virtio_rpmsg_channel *vch = to_virtio_rpmsg_channel(ept->rpdev); |
305 | ||
306 | __rpmsg_destroy_ept(vch->vrp, ept); | |
8a228ecf BA |
307 | } |
308 | ||
36b72c7d BA |
309 | static int virtio_rpmsg_announce_create(struct rpmsg_device *rpdev) |
310 | { | |
3bf950ff BA |
311 | struct virtio_rpmsg_channel *vch = to_virtio_rpmsg_channel(rpdev); |
312 | struct virtproc_info *vrp = vch->vrp; | |
36b72c7d BA |
313 | struct device *dev = &rpdev->dev; |
314 | int err = 0; | |
315 | ||
bcabbcca OBC |
316 | /* need to tell remote processor's name service about this channel ? */ |
317 | if (rpdev->announce && | |
0963679c | 318 | virtio_has_feature(vrp->vdev, VIRTIO_RPMSG_F_NS)) { |
bcabbcca OBC |
319 | struct rpmsg_ns_msg nsm; |
320 | ||
321 | strncpy(nsm.name, rpdev->id.name, RPMSG_NAME_SIZE); | |
2a48d732 | 322 | nsm.addr = rpdev->ept->addr; |
bcabbcca OBC |
323 | nsm.flags = RPMSG_NS_CREATE; |
324 | ||
2a48d732 | 325 | err = rpmsg_sendto(rpdev->ept, &nsm, sizeof(nsm), RPMSG_NS_ADDR); |
bcabbcca OBC |
326 | if (err) |
327 | dev_err(dev, "failed to announce service %d\n", err); | |
328 | } | |
329 | ||
bcabbcca OBC |
330 | return err; |
331 | } | |
332 | ||
36b72c7d | 333 | static int virtio_rpmsg_announce_destroy(struct rpmsg_device *rpdev) |
bcabbcca | 334 | { |
3bf950ff BA |
335 | struct virtio_rpmsg_channel *vch = to_virtio_rpmsg_channel(rpdev); |
336 | struct virtproc_info *vrp = vch->vrp; | |
36b72c7d | 337 | struct device *dev = &rpdev->dev; |
bcabbcca OBC |
338 | int err = 0; |
339 | ||
340 | /* tell remote processor's name service we're removing this channel */ | |
341 | if (rpdev->announce && | |
0963679c | 342 | virtio_has_feature(vrp->vdev, VIRTIO_RPMSG_F_NS)) { |
bcabbcca OBC |
343 | struct rpmsg_ns_msg nsm; |
344 | ||
345 | strncpy(nsm.name, rpdev->id.name, RPMSG_NAME_SIZE); | |
346 | nsm.addr = rpdev->src; | |
347 | nsm.flags = RPMSG_NS_DESTROY; | |
348 | ||
2a48d732 | 349 | err = rpmsg_sendto(rpdev->ept, &nsm, sizeof(nsm), RPMSG_NS_ADDR); |
bcabbcca OBC |
350 | if (err) |
351 | dev_err(dev, "failed to announce service %d\n", err); | |
352 | } | |
353 | ||
36b72c7d BA |
354 | return err; |
355 | } | |
356 | ||
36b72c7d BA |
357 | static const struct rpmsg_device_ops virtio_rpmsg_ops = { |
358 | .create_ept = virtio_rpmsg_create_ept, | |
359 | .announce_create = virtio_rpmsg_announce_create, | |
360 | .announce_destroy = virtio_rpmsg_announce_destroy, | |
361 | }; | |
362 | ||
b0b03b81 BA |
363 | static void virtio_rpmsg_release_device(struct device *dev) |
364 | { | |
365 | struct rpmsg_device *rpdev = to_rpmsg_device(dev); | |
366 | struct virtio_rpmsg_channel *vch = to_virtio_rpmsg_channel(rpdev); | |
367 | ||
368 | kfree(vch); | |
369 | } | |
370 | ||
bcabbcca OBC |
371 | /* |
372 | * create an rpmsg channel using its name and address info. | |
373 | * this function will be used to create both static and dynamic | |
374 | * channels. | |
375 | */ | |
92e1de51 BA |
376 | static struct rpmsg_device *rpmsg_create_channel(struct virtproc_info *vrp, |
377 | struct rpmsg_channel_info *chinfo) | |
bcabbcca | 378 | { |
3bf950ff | 379 | struct virtio_rpmsg_channel *vch; |
92e1de51 | 380 | struct rpmsg_device *rpdev; |
bcabbcca OBC |
381 | struct device *tmp, *dev = &vrp->vdev->dev; |
382 | int ret; | |
383 | ||
384 | /* make sure a similar channel doesn't already exist */ | |
8b881c07 | 385 | tmp = rpmsg_find_device(dev, chinfo); |
bcabbcca OBC |
386 | if (tmp) { |
387 | /* decrement the matched device's refcount back */ | |
388 | put_device(tmp); | |
389 | dev_err(dev, "channel %s:%x:%x already exist\n", | |
390 | chinfo->name, chinfo->src, chinfo->dst); | |
391 | return NULL; | |
392 | } | |
393 | ||
3bf950ff BA |
394 | vch = kzalloc(sizeof(*vch), GFP_KERNEL); |
395 | if (!vch) | |
bcabbcca | 396 | return NULL; |
bcabbcca | 397 | |
3bf950ff BA |
398 | /* Link the channel to our vrp */ |
399 | vch->vrp = vrp; | |
400 | ||
401 | /* Assign callbacks for rpmsg_channel */ | |
402 | vch->rpdev.ops = &virtio_rpmsg_ops; | |
403 | ||
404 | /* Assign public information to the rpmsg_device */ | |
405 | rpdev = &vch->rpdev; | |
bcabbcca OBC |
406 | rpdev->src = chinfo->src; |
407 | rpdev->dst = chinfo->dst; | |
36b72c7d | 408 | rpdev->ops = &virtio_rpmsg_ops; |
bcabbcca OBC |
409 | |
410 | /* | |
411 | * rpmsg server channels has predefined local address (for now), | |
412 | * and their existence needs to be announced remotely | |
413 | */ | |
c8ced113 | 414 | rpdev->announce = rpdev->src != RPMSG_ADDR_ANY; |
bcabbcca OBC |
415 | |
416 | strncpy(rpdev->id.name, chinfo->name, RPMSG_NAME_SIZE); | |
417 | ||
6eed598a | 418 | rpdev->dev.parent = &vrp->vdev->dev; |
b0b03b81 | 419 | rpdev->dev.release = virtio_rpmsg_release_device; |
6eed598a BA |
420 | ret = rpmsg_register_device(rpdev); |
421 | if (ret) | |
422 | return NULL; | |
423 | ||
424 | return rpdev; | |
425 | } | |
426 | ||
bcabbcca OBC |
427 | /* super simple buffer "allocator" that is just enough for now */ |
428 | static void *get_a_tx_buf(struct virtproc_info *vrp) | |
429 | { | |
430 | unsigned int len; | |
431 | void *ret; | |
432 | ||
433 | /* support multiple concurrent senders */ | |
434 | mutex_lock(&vrp->tx_lock); | |
435 | ||
436 | /* | |
437 | * either pick the next unused tx buffer | |
438 | * (half of our buffers are used for sending messages) | |
439 | */ | |
b1b98914 | 440 | if (vrp->last_sbuf < vrp->num_bufs / 2) |
bcabbcca OBC |
441 | ret = vrp->sbufs + RPMSG_BUF_SIZE * vrp->last_sbuf++; |
442 | /* or recycle a used one */ | |
443 | else | |
444 | ret = virtqueue_get_buf(vrp->svq, &len); | |
445 | ||
446 | mutex_unlock(&vrp->tx_lock); | |
447 | ||
448 | return ret; | |
449 | } | |
450 | ||
451 | /** | |
452 | * rpmsg_upref_sleepers() - enable "tx-complete" interrupts, if needed | |
453 | * @vrp: virtual remote processor state | |
454 | * | |
455 | * This function is called before a sender is blocked, waiting for | |
456 | * a tx buffer to become available. | |
457 | * | |
458 | * If we already have blocking senders, this function merely increases | |
459 | * the "sleepers" reference count, and exits. | |
460 | * | |
461 | * Otherwise, if this is the first sender to block, we also enable | |
462 | * virtio's tx callbacks, so we'd be immediately notified when a tx | |
463 | * buffer is consumed (we rely on virtio's tx callback in order | |
464 | * to wake up sleeping senders as soon as a tx buffer is used by the | |
465 | * remote processor). | |
466 | */ | |
467 | static void rpmsg_upref_sleepers(struct virtproc_info *vrp) | |
468 | { | |
469 | /* support multiple concurrent senders */ | |
470 | mutex_lock(&vrp->tx_lock); | |
471 | ||
472 | /* are we the first sleeping context waiting for tx buffers ? */ | |
473 | if (atomic_inc_return(&vrp->sleepers) == 1) | |
474 | /* enable "tx-complete" interrupts before dozing off */ | |
475 | virtqueue_enable_cb(vrp->svq); | |
476 | ||
477 | mutex_unlock(&vrp->tx_lock); | |
478 | } | |
479 | ||
480 | /** | |
481 | * rpmsg_downref_sleepers() - disable "tx-complete" interrupts, if needed | |
482 | * @vrp: virtual remote processor state | |
483 | * | |
484 | * This function is called after a sender, that waited for a tx buffer | |
485 | * to become available, is unblocked. | |
486 | * | |
487 | * If we still have blocking senders, this function merely decreases | |
488 | * the "sleepers" reference count, and exits. | |
489 | * | |
490 | * Otherwise, if there are no more blocking senders, we also disable | |
491 | * virtio's tx callbacks, to avoid the overhead incurred with handling | |
492 | * those (now redundant) interrupts. | |
493 | */ | |
494 | static void rpmsg_downref_sleepers(struct virtproc_info *vrp) | |
495 | { | |
496 | /* support multiple concurrent senders */ | |
497 | mutex_lock(&vrp->tx_lock); | |
498 | ||
499 | /* are we the last sleeping context waiting for tx buffers ? */ | |
500 | if (atomic_dec_and_test(&vrp->sleepers)) | |
501 | /* disable "tx-complete" interrupts */ | |
502 | virtqueue_disable_cb(vrp->svq); | |
503 | ||
504 | mutex_unlock(&vrp->tx_lock); | |
505 | } | |
506 | ||
507 | /** | |
508 | * rpmsg_send_offchannel_raw() - send a message across to the remote processor | |
509 | * @rpdev: the rpmsg channel | |
510 | * @src: source address | |
511 | * @dst: destination address | |
512 | * @data: payload of message | |
513 | * @len: length of payload | |
514 | * @wait: indicates whether caller should block in case no TX buffers available | |
515 | * | |
516 | * This function is the base implementation for all of the rpmsg sending API. | |
517 | * | |
518 | * It will send @data of length @len to @dst, and say it's from @src. The | |
519 | * message will be sent to the remote processor which the @rpdev channel | |
520 | * belongs to. | |
521 | * | |
522 | * The message is sent using one of the TX buffers that are available for | |
523 | * communication with this remote processor. | |
524 | * | |
525 | * If @wait is true, the caller will be blocked until either a TX buffer is | |
526 | * available, or 15 seconds elapses (we don't want callers to | |
527 | * sleep indefinitely due to misbehaving remote processors), and in that | |
528 | * case -ERESTARTSYS is returned. The number '15' itself was picked | |
529 | * arbitrarily; there's little point in asking drivers to provide a timeout | |
530 | * value themselves. | |
531 | * | |
532 | * Otherwise, if @wait is false, and there are no TX buffers available, | |
533 | * the function will immediately fail, and -ENOMEM will be returned. | |
534 | * | |
535 | * Normally drivers shouldn't use this function directly; instead, drivers | |
536 | * should use the appropriate rpmsg_{try}send{to, _offchannel} API | |
537 | * (see include/linux/rpmsg.h). | |
538 | * | |
539 | * Returns 0 on success and an appropriate error value on failure. | |
540 | */ | |
8a228ecf BA |
541 | static int rpmsg_send_offchannel_raw(struct rpmsg_device *rpdev, |
542 | u32 src, u32 dst, | |
543 | void *data, int len, bool wait) | |
bcabbcca | 544 | { |
3bf950ff BA |
545 | struct virtio_rpmsg_channel *vch = to_virtio_rpmsg_channel(rpdev); |
546 | struct virtproc_info *vrp = vch->vrp; | |
bcabbcca OBC |
547 | struct device *dev = &rpdev->dev; |
548 | struct scatterlist sg; | |
549 | struct rpmsg_hdr *msg; | |
550 | int err; | |
551 | ||
552 | /* bcasting isn't allowed */ | |
553 | if (src == RPMSG_ADDR_ANY || dst == RPMSG_ADDR_ANY) { | |
554 | dev_err(dev, "invalid addr (src 0x%x, dst 0x%x)\n", src, dst); | |
555 | return -EINVAL; | |
556 | } | |
557 | ||
558 | /* | |
559 | * We currently use fixed-sized buffers, and therefore the payload | |
560 | * length is limited. | |
561 | * | |
562 | * One of the possible improvements here is either to support | |
563 | * user-provided buffers (and then we can also support zero-copy | |
564 | * messaging), or to improve the buffer allocator, to support | |
565 | * variable-length buffer sizes. | |
566 | */ | |
567 | if (len > RPMSG_BUF_SIZE - sizeof(struct rpmsg_hdr)) { | |
568 | dev_err(dev, "message is too big (%d)\n", len); | |
569 | return -EMSGSIZE; | |
570 | } | |
571 | ||
572 | /* grab a buffer */ | |
573 | msg = get_a_tx_buf(vrp); | |
574 | if (!msg && !wait) | |
575 | return -ENOMEM; | |
576 | ||
577 | /* no free buffer ? wait for one (but bail after 15 seconds) */ | |
578 | while (!msg) { | |
579 | /* enable "tx-complete" interrupts, if not already enabled */ | |
580 | rpmsg_upref_sleepers(vrp); | |
581 | ||
582 | /* | |
583 | * sleep until a free buffer is available or 15 secs elapse. | |
584 | * the timeout period is not configurable because there's | |
585 | * little point in asking drivers to specify that. | |
586 | * if later this happens to be required, it'd be easy to add. | |
587 | */ | |
588 | err = wait_event_interruptible_timeout(vrp->sendq, | |
589 | (msg = get_a_tx_buf(vrp)), | |
590 | msecs_to_jiffies(15000)); | |
591 | ||
592 | /* disable "tx-complete" interrupts if we're the last sleeper */ | |
593 | rpmsg_downref_sleepers(vrp); | |
594 | ||
595 | /* timeout ? */ | |
596 | if (!err) { | |
597 | dev_err(dev, "timeout waiting for a tx buffer\n"); | |
598 | return -ERESTARTSYS; | |
599 | } | |
600 | } | |
601 | ||
602 | msg->len = len; | |
603 | msg->flags = 0; | |
604 | msg->src = src; | |
605 | msg->dst = dst; | |
606 | msg->reserved = 0; | |
607 | memcpy(msg->data, data, len); | |
608 | ||
609 | dev_dbg(dev, "TX From 0x%x, To 0x%x, Len %d, Flags %d, Reserved %d\n", | |
0963679c | 610 | msg->src, msg->dst, msg->len, msg->flags, msg->reserved); |
211e3a93 AS |
611 | #if defined(CONFIG_DYNAMIC_DEBUG) |
612 | dynamic_hex_dump("rpmsg_virtio TX: ", DUMP_PREFIX_NONE, 16, 1, | |
613 | msg, sizeof(*msg) + msg->len, true); | |
614 | #endif | |
bcabbcca OBC |
615 | |
616 | sg_init_one(&sg, msg, sizeof(*msg) + len); | |
617 | ||
618 | mutex_lock(&vrp->tx_lock); | |
619 | ||
620 | /* add message to the remote processor's virtqueue */ | |
cee51d69 | 621 | err = virtqueue_add_outbuf(vrp->svq, &sg, 1, msg, GFP_KERNEL); |
57e1a373 | 622 | if (err) { |
bcabbcca OBC |
623 | /* |
624 | * need to reclaim the buffer here, otherwise it's lost | |
625 | * (memory won't leak, but rpmsg won't use it again for TX). | |
626 | * this will wait for a buffer management overhaul. | |
627 | */ | |
cee51d69 | 628 | dev_err(dev, "virtqueue_add_outbuf failed: %d\n", err); |
bcabbcca OBC |
629 | goto out; |
630 | } | |
631 | ||
632 | /* tell the remote processor it has a pending message to read */ | |
633 | virtqueue_kick(vrp->svq); | |
bcabbcca OBC |
634 | out: |
635 | mutex_unlock(&vrp->tx_lock); | |
636 | return err; | |
637 | } | |
638 | EXPORT_SYMBOL(rpmsg_send_offchannel_raw); | |
639 | ||
8a228ecf BA |
640 | static int virtio_rpmsg_send(struct rpmsg_endpoint *ept, void *data, int len) |
641 | { | |
642 | struct rpmsg_device *rpdev = ept->rpdev; | |
643 | u32 src = ept->addr, dst = rpdev->dst; | |
644 | ||
645 | return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, true); | |
646 | } | |
647 | ||
648 | static int virtio_rpmsg_sendto(struct rpmsg_endpoint *ept, void *data, int len, | |
649 | u32 dst) | |
650 | { | |
651 | struct rpmsg_device *rpdev = ept->rpdev; | |
652 | u32 src = ept->addr; | |
653 | ||
654 | return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, true); | |
655 | } | |
656 | ||
657 | static int virtio_rpmsg_send_offchannel(struct rpmsg_endpoint *ept, u32 src, | |
658 | u32 dst, void *data, int len) | |
659 | { | |
660 | struct rpmsg_device *rpdev = ept->rpdev; | |
661 | ||
662 | return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, true); | |
663 | } | |
664 | ||
665 | static int virtio_rpmsg_trysend(struct rpmsg_endpoint *ept, void *data, int len) | |
666 | { | |
667 | struct rpmsg_device *rpdev = ept->rpdev; | |
668 | u32 src = ept->addr, dst = rpdev->dst; | |
669 | ||
670 | return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, false); | |
671 | } | |
672 | ||
673 | static int virtio_rpmsg_trysendto(struct rpmsg_endpoint *ept, void *data, | |
674 | int len, u32 dst) | |
675 | { | |
676 | struct rpmsg_device *rpdev = ept->rpdev; | |
677 | u32 src = ept->addr; | |
678 | ||
679 | return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, false); | |
680 | } | |
681 | ||
682 | static int virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, | |
683 | u32 dst, void *data, int len) | |
684 | { | |
685 | struct rpmsg_device *rpdev = ept->rpdev; | |
686 | ||
687 | return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, false); | |
688 | } | |
689 | ||
1aa7d6a5 RT |
690 | static int rpmsg_recv_single(struct virtproc_info *vrp, struct device *dev, |
691 | struct rpmsg_hdr *msg, unsigned int len) | |
bcabbcca | 692 | { |
bcabbcca OBC |
693 | struct rpmsg_endpoint *ept; |
694 | struct scatterlist sg; | |
bcabbcca OBC |
695 | int err; |
696 | ||
bcabbcca | 697 | dev_dbg(dev, "From: 0x%x, To: 0x%x, Len: %d, Flags: %d, Reserved: %d\n", |
0963679c | 698 | msg->src, msg->dst, msg->len, msg->flags, msg->reserved); |
211e3a93 AS |
699 | #if defined(CONFIG_DYNAMIC_DEBUG) |
700 | dynamic_hex_dump("rpmsg_virtio RX: ", DUMP_PREFIX_NONE, 16, 1, | |
701 | msg, sizeof(*msg) + msg->len, true); | |
702 | #endif | |
bcabbcca | 703 | |
9648224e OBC |
704 | /* |
705 | * We currently use fixed-sized buffers, so trivially sanitize | |
706 | * the reported payload length. | |
707 | */ | |
708 | if (len > RPMSG_BUF_SIZE || | |
0963679c | 709 | msg->len > (len - sizeof(struct rpmsg_hdr))) { |
9648224e | 710 | dev_warn(dev, "inbound msg too big: (%d, %d)\n", len, msg->len); |
1aa7d6a5 | 711 | return -EINVAL; |
9648224e OBC |
712 | } |
713 | ||
bcabbcca OBC |
714 | /* use the dst addr to fetch the callback of the appropriate user */ |
715 | mutex_lock(&vrp->endpoints_lock); | |
5a081caa | 716 | |
bcabbcca | 717 | ept = idr_find(&vrp->endpoints, msg->dst); |
5a081caa OBC |
718 | |
719 | /* let's make sure no one deallocates ept while we use it */ | |
720 | if (ept) | |
721 | kref_get(&ept->refcount); | |
722 | ||
bcabbcca OBC |
723 | mutex_unlock(&vrp->endpoints_lock); |
724 | ||
15fd943a OBC |
725 | if (ept) { |
726 | /* make sure ept->cb doesn't go away while we use it */ | |
727 | mutex_lock(&ept->cb_lock); | |
bcabbcca | 728 | |
15fd943a OBC |
729 | if (ept->cb) |
730 | ept->cb(ept->rpdev, msg->data, msg->len, ept->priv, | |
731 | msg->src); | |
732 | ||
733 | mutex_unlock(&ept->cb_lock); | |
734 | ||
735 | /* farewell, ept, we don't need you anymore */ | |
5a081caa | 736 | kref_put(&ept->refcount, __ept_release); |
15fd943a | 737 | } else |
8a168ca7 | 738 | dev_warn(dev, "msg received with no recipient\n"); |
5a081caa | 739 | |
f1d9e9c7 OBC |
740 | /* publish the real size of the buffer */ |
741 | sg_init_one(&sg, msg, RPMSG_BUF_SIZE); | |
bcabbcca OBC |
742 | |
743 | /* add the buffer back to the remote processor's virtqueue */ | |
cee51d69 | 744 | err = virtqueue_add_inbuf(vrp->rvq, &sg, 1, msg, GFP_KERNEL); |
bcabbcca OBC |
745 | if (err < 0) { |
746 | dev_err(dev, "failed to add a virtqueue buffer: %d\n", err); | |
1aa7d6a5 RT |
747 | return err; |
748 | } | |
749 | ||
750 | return 0; | |
751 | } | |
752 | ||
753 | /* called when an rx buffer is used, and it's time to digest a message */ | |
754 | static void rpmsg_recv_done(struct virtqueue *rvq) | |
755 | { | |
756 | struct virtproc_info *vrp = rvq->vdev->priv; | |
757 | struct device *dev = &rvq->vdev->dev; | |
758 | struct rpmsg_hdr *msg; | |
759 | unsigned int len, msgs_received = 0; | |
760 | int err; | |
761 | ||
762 | msg = virtqueue_get_buf(rvq, &len); | |
763 | if (!msg) { | |
764 | dev_err(dev, "uhm, incoming signal, but no used buffer ?\n"); | |
bcabbcca OBC |
765 | return; |
766 | } | |
767 | ||
1aa7d6a5 RT |
768 | while (msg) { |
769 | err = rpmsg_recv_single(vrp, dev, msg, len); | |
770 | if (err) | |
771 | break; | |
772 | ||
773 | msgs_received++; | |
774 | ||
775 | msg = virtqueue_get_buf(rvq, &len); | |
6c49fbe3 | 776 | } |
1aa7d6a5 RT |
777 | |
778 | dev_dbg(dev, "Received %u messages\n", msgs_received); | |
779 | ||
bcabbcca | 780 | /* tell the remote processor we added another available rx buffer */ |
1aa7d6a5 RT |
781 | if (msgs_received) |
782 | virtqueue_kick(vrp->rvq); | |
bcabbcca OBC |
783 | } |
784 | ||
785 | /* | |
786 | * This is invoked whenever the remote processor completed processing | |
787 | * a TX msg we just sent it, and the buffer is put back to the used ring. | |
788 | * | |
789 | * Normally, though, we suppress this "tx complete" interrupt in order to | |
790 | * avoid the incurred overhead. | |
791 | */ | |
792 | static void rpmsg_xmit_done(struct virtqueue *svq) | |
793 | { | |
794 | struct virtproc_info *vrp = svq->vdev->priv; | |
795 | ||
796 | dev_dbg(&svq->vdev->dev, "%s\n", __func__); | |
797 | ||
798 | /* wake up potential senders that are waiting for a tx buffer */ | |
799 | wake_up_interruptible(&vrp->sendq); | |
800 | } | |
801 | ||
802 | /* invoked when a name service announcement arrives */ | |
4b83c52a BA |
803 | static int rpmsg_ns_cb(struct rpmsg_device *rpdev, void *data, int len, |
804 | void *priv, u32 src) | |
bcabbcca OBC |
805 | { |
806 | struct rpmsg_ns_msg *msg = data; | |
92e1de51 | 807 | struct rpmsg_device *newch; |
bcabbcca OBC |
808 | struct rpmsg_channel_info chinfo; |
809 | struct virtproc_info *vrp = priv; | |
810 | struct device *dev = &vrp->vdev->dev; | |
811 | int ret; | |
812 | ||
211e3a93 AS |
813 | #if defined(CONFIG_DYNAMIC_DEBUG) |
814 | dynamic_hex_dump("NS announcement: ", DUMP_PREFIX_NONE, 16, 1, | |
815 | data, len, true); | |
816 | #endif | |
bcabbcca OBC |
817 | |
818 | if (len != sizeof(*msg)) { | |
819 | dev_err(dev, "malformed ns msg (%d)\n", len); | |
4b83c52a | 820 | return -EINVAL; |
bcabbcca OBC |
821 | } |
822 | ||
823 | /* | |
824 | * the name service ept does _not_ belong to a real rpmsg channel, | |
825 | * and is handled by the rpmsg bus itself. | |
826 | * for sanity reasons, make sure a valid rpdev has _not_ sneaked | |
827 | * in somehow. | |
828 | */ | |
829 | if (rpdev) { | |
830 | dev_err(dev, "anomaly: ns ept has an rpdev handle\n"); | |
4b83c52a | 831 | return -EINVAL; |
bcabbcca OBC |
832 | } |
833 | ||
834 | /* don't trust the remote processor for null terminating the name */ | |
835 | msg->name[RPMSG_NAME_SIZE - 1] = '\0'; | |
836 | ||
837 | dev_info(dev, "%sing channel %s addr 0x%x\n", | |
0963679c AS |
838 | msg->flags & RPMSG_NS_DESTROY ? "destroy" : "creat", |
839 | msg->name, msg->addr); | |
bcabbcca OBC |
840 | |
841 | strncpy(chinfo.name, msg->name, sizeof(chinfo.name)); | |
842 | chinfo.src = RPMSG_ADDR_ANY; | |
843 | chinfo.dst = msg->addr; | |
844 | ||
845 | if (msg->flags & RPMSG_NS_DESTROY) { | |
5e619b48 | 846 | ret = rpmsg_unregister_device(&vrp->vdev->dev, &chinfo); |
bcabbcca OBC |
847 | if (ret) |
848 | dev_err(dev, "rpmsg_destroy_channel failed: %d\n", ret); | |
849 | } else { | |
850 | newch = rpmsg_create_channel(vrp, &chinfo); | |
851 | if (!newch) | |
852 | dev_err(dev, "rpmsg_create_channel failed\n"); | |
853 | } | |
4b83c52a BA |
854 | |
855 | return 0; | |
bcabbcca OBC |
856 | } |
857 | ||
858 | static int rpmsg_probe(struct virtio_device *vdev) | |
859 | { | |
860 | vq_callback_t *vq_cbs[] = { rpmsg_recv_done, rpmsg_xmit_done }; | |
f7ad26ff | 861 | static const char * const names[] = { "input", "output" }; |
bcabbcca OBC |
862 | struct virtqueue *vqs[2]; |
863 | struct virtproc_info *vrp; | |
864 | void *bufs_va; | |
865 | int err = 0, i; | |
b1b98914 | 866 | size_t total_buf_space; |
71e4b8bf | 867 | bool notify; |
bcabbcca OBC |
868 | |
869 | vrp = kzalloc(sizeof(*vrp), GFP_KERNEL); | |
870 | if (!vrp) | |
871 | return -ENOMEM; | |
872 | ||
873 | vrp->vdev = vdev; | |
874 | ||
875 | idr_init(&vrp->endpoints); | |
876 | mutex_init(&vrp->endpoints_lock); | |
877 | mutex_init(&vrp->tx_lock); | |
878 | init_waitqueue_head(&vrp->sendq); | |
879 | ||
880 | /* We expect two virtqueues, rx and tx (and in this order) */ | |
9b2bbdb2 | 881 | err = virtio_find_vqs(vdev, 2, vqs, vq_cbs, names, NULL); |
bcabbcca OBC |
882 | if (err) |
883 | goto free_vrp; | |
884 | ||
885 | vrp->rvq = vqs[0]; | |
886 | vrp->svq = vqs[1]; | |
887 | ||
b1b98914 SA |
888 | /* we expect symmetric tx/rx vrings */ |
889 | WARN_ON(virtqueue_get_vring_size(vrp->rvq) != | |
890 | virtqueue_get_vring_size(vrp->svq)); | |
891 | ||
892 | /* we need less buffers if vrings are small */ | |
893 | if (virtqueue_get_vring_size(vrp->rvq) < MAX_RPMSG_NUM_BUFS / 2) | |
894 | vrp->num_bufs = virtqueue_get_vring_size(vrp->rvq) * 2; | |
895 | else | |
896 | vrp->num_bufs = MAX_RPMSG_NUM_BUFS; | |
897 | ||
898 | total_buf_space = vrp->num_bufs * RPMSG_BUF_SIZE; | |
899 | ||
bcabbcca | 900 | /* allocate coherent memory for the buffers */ |
b5ab5e24 | 901 | bufs_va = dma_alloc_coherent(vdev->dev.parent->parent, |
b1b98914 SA |
902 | total_buf_space, &vrp->bufs_dma, |
903 | GFP_KERNEL); | |
3119b487 WY |
904 | if (!bufs_va) { |
905 | err = -ENOMEM; | |
bcabbcca | 906 | goto vqs_del; |
3119b487 | 907 | } |
bcabbcca | 908 | |
8d95b322 AS |
909 | dev_dbg(&vdev->dev, "buffers: va %p, dma %pad\n", |
910 | bufs_va, &vrp->bufs_dma); | |
bcabbcca OBC |
911 | |
912 | /* half of the buffers is dedicated for RX */ | |
913 | vrp->rbufs = bufs_va; | |
914 | ||
915 | /* and half is dedicated for TX */ | |
b1b98914 | 916 | vrp->sbufs = bufs_va + total_buf_space / 2; |
bcabbcca OBC |
917 | |
918 | /* set up the receive buffers */ | |
b1b98914 | 919 | for (i = 0; i < vrp->num_bufs / 2; i++) { |
bcabbcca OBC |
920 | struct scatterlist sg; |
921 | void *cpu_addr = vrp->rbufs + i * RPMSG_BUF_SIZE; | |
922 | ||
923 | sg_init_one(&sg, cpu_addr, RPMSG_BUF_SIZE); | |
924 | ||
cee51d69 | 925 | err = virtqueue_add_inbuf(vrp->rvq, &sg, 1, cpu_addr, |
0963679c | 926 | GFP_KERNEL); |
57e1a373 | 927 | WARN_ON(err); /* sanity check; this can't really happen */ |
bcabbcca OBC |
928 | } |
929 | ||
930 | /* suppress "tx-complete" interrupts */ | |
931 | virtqueue_disable_cb(vrp->svq); | |
932 | ||
933 | vdev->priv = vrp; | |
934 | ||
935 | /* if supported by the remote processor, enable the name service */ | |
936 | if (virtio_has_feature(vdev, VIRTIO_RPMSG_F_NS)) { | |
937 | /* a dedicated endpoint handles the name service msgs */ | |
938 | vrp->ns_ept = __rpmsg_create_ept(vrp, NULL, rpmsg_ns_cb, | |
939 | vrp, RPMSG_NS_ADDR); | |
940 | if (!vrp->ns_ept) { | |
941 | dev_err(&vdev->dev, "failed to create the ns ept\n"); | |
942 | err = -ENOMEM; | |
943 | goto free_coherent; | |
944 | } | |
945 | } | |
946 | ||
71e4b8bf MT |
947 | /* |
948 | * Prepare to kick but don't notify yet - we can't do this before | |
949 | * device is ready. | |
950 | */ | |
951 | notify = virtqueue_kick_prepare(vrp->rvq); | |
952 | ||
953 | /* From this point on, we can notify and get callbacks. */ | |
954 | virtio_device_ready(vdev); | |
955 | ||
bcabbcca | 956 | /* tell the remote processor it can start sending messages */ |
71e4b8bf MT |
957 | /* |
958 | * this might be concurrent with callbacks, but we are only | |
959 | * doing notify, not a full kick here, so that's ok. | |
960 | */ | |
961 | if (notify) | |
962 | virtqueue_notify(vrp->rvq); | |
bcabbcca OBC |
963 | |
964 | dev_info(&vdev->dev, "rpmsg host is online\n"); | |
965 | ||
966 | return 0; | |
967 | ||
968 | free_coherent: | |
b1b98914 SA |
969 | dma_free_coherent(vdev->dev.parent->parent, total_buf_space, |
970 | bufs_va, vrp->bufs_dma); | |
bcabbcca OBC |
971 | vqs_del: |
972 | vdev->config->del_vqs(vrp->vdev); | |
973 | free_vrp: | |
974 | kfree(vrp); | |
975 | return err; | |
976 | } | |
977 | ||
978 | static int rpmsg_remove_device(struct device *dev, void *data) | |
979 | { | |
980 | device_unregister(dev); | |
981 | ||
982 | return 0; | |
983 | } | |
984 | ||
0fe763c5 | 985 | static void rpmsg_remove(struct virtio_device *vdev) |
bcabbcca OBC |
986 | { |
987 | struct virtproc_info *vrp = vdev->priv; | |
b1b98914 | 988 | size_t total_buf_space = vrp->num_bufs * RPMSG_BUF_SIZE; |
bcabbcca OBC |
989 | int ret; |
990 | ||
991 | vdev->config->reset(vdev); | |
992 | ||
993 | ret = device_for_each_child(&vdev->dev, NULL, rpmsg_remove_device); | |
994 | if (ret) | |
995 | dev_warn(&vdev->dev, "can't remove rpmsg device: %d\n", ret); | |
996 | ||
fa2d7795 OBC |
997 | if (vrp->ns_ept) |
998 | __rpmsg_destroy_ept(vrp, vrp->ns_ept); | |
999 | ||
bcabbcca OBC |
1000 | idr_destroy(&vrp->endpoints); |
1001 | ||
1002 | vdev->config->del_vqs(vrp->vdev); | |
1003 | ||
b1b98914 SA |
1004 | dma_free_coherent(vdev->dev.parent->parent, total_buf_space, |
1005 | vrp->rbufs, vrp->bufs_dma); | |
bcabbcca OBC |
1006 | |
1007 | kfree(vrp); | |
1008 | } | |
1009 | ||
1010 | static struct virtio_device_id id_table[] = { | |
1011 | { VIRTIO_ID_RPMSG, VIRTIO_DEV_ANY_ID }, | |
1012 | { 0 }, | |
1013 | }; | |
1014 | ||
1015 | static unsigned int features[] = { | |
1016 | VIRTIO_RPMSG_F_NS, | |
1017 | }; | |
1018 | ||
1019 | static struct virtio_driver virtio_ipc_driver = { | |
1020 | .feature_table = features, | |
1021 | .feature_table_size = ARRAY_SIZE(features), | |
1022 | .driver.name = KBUILD_MODNAME, | |
1023 | .driver.owner = THIS_MODULE, | |
1024 | .id_table = id_table, | |
1025 | .probe = rpmsg_probe, | |
0fe763c5 | 1026 | .remove = rpmsg_remove, |
bcabbcca OBC |
1027 | }; |
1028 | ||
1029 | static int __init rpmsg_init(void) | |
1030 | { | |
1031 | int ret; | |
1032 | ||
bcabbcca | 1033 | ret = register_virtio_driver(&virtio_ipc_driver); |
5e619b48 | 1034 | if (ret) |
bcabbcca | 1035 | pr_err("failed to register virtio driver: %d\n", ret); |
bcabbcca OBC |
1036 | |
1037 | return ret; | |
1038 | } | |
96342526 | 1039 | subsys_initcall(rpmsg_init); |
bcabbcca OBC |
1040 | |
1041 | static void __exit rpmsg_fini(void) | |
1042 | { | |
1043 | unregister_virtio_driver(&virtio_ipc_driver); | |
bcabbcca OBC |
1044 | } |
1045 | module_exit(rpmsg_fini); | |
1046 | ||
1047 | MODULE_DEVICE_TABLE(virtio, id_table); | |
1048 | MODULE_DESCRIPTION("Virtio-based remote processor messaging bus"); | |
1049 | MODULE_LICENSE("GPL v2"); |