xref: /openbmc/linux/drivers/misc/fastrpc.c (revision ecd25094)
1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (c) 2011-2018, The Linux Foundation. All rights reserved.
3 // Copyright (c) 2018, Linaro Limited
4 
5 #include <linux/completion.h>
6 #include <linux/device.h>
7 #include <linux/dma-buf.h>
8 #include <linux/dma-mapping.h>
9 #include <linux/idr.h>
10 #include <linux/list.h>
11 #include <linux/miscdevice.h>
12 #include <linux/module.h>
13 #include <linux/of_address.h>
14 #include <linux/of.h>
15 #include <linux/sort.h>
16 #include <linux/of_platform.h>
17 #include <linux/rpmsg.h>
18 #include <linux/scatterlist.h>
19 #include <linux/slab.h>
20 #include <uapi/misc/fastrpc.h>
21 
22 #define ADSP_DOMAIN_ID (0)
23 #define MDSP_DOMAIN_ID (1)
24 #define SDSP_DOMAIN_ID (2)
25 #define CDSP_DOMAIN_ID (3)
26 #define FASTRPC_DEV_MAX		4 /* adsp, mdsp, slpi, cdsp*/
27 #define FASTRPC_MAX_SESSIONS	9 /*8 compute, 1 cpz*/
28 #define FASTRPC_ALIGN		128
29 #define FASTRPC_MAX_FDLIST	16
30 #define FASTRPC_MAX_CRCLIST	64
31 #define FASTRPC_PHYS(p)	((p) & 0xffffffff)
32 #define FASTRPC_CTX_MAX (256)
33 #define FASTRPC_INIT_HANDLE	1
34 #define FASTRPC_CTXID_MASK (0xFF0)
35 #define INIT_FILELEN_MAX (64 * 1024 * 1024)
36 #define FASTRPC_DEVICE_NAME	"fastrpc"
37 
38 /* Retrives number of input buffers from the scalars parameter */
39 #define REMOTE_SCALARS_INBUFS(sc)	(((sc) >> 16) & 0x0ff)
40 
41 /* Retrives number of output buffers from the scalars parameter */
42 #define REMOTE_SCALARS_OUTBUFS(sc)	(((sc) >> 8) & 0x0ff)
43 
44 /* Retrives number of input handles from the scalars parameter */
45 #define REMOTE_SCALARS_INHANDLES(sc)	(((sc) >> 4) & 0x0f)
46 
47 /* Retrives number of output handles from the scalars parameter */
48 #define REMOTE_SCALARS_OUTHANDLES(sc)	((sc) & 0x0f)
49 
50 #define REMOTE_SCALARS_LENGTH(sc)	(REMOTE_SCALARS_INBUFS(sc) +   \
51 					 REMOTE_SCALARS_OUTBUFS(sc) +  \
52 					 REMOTE_SCALARS_INHANDLES(sc)+ \
53 					 REMOTE_SCALARS_OUTHANDLES(sc))
54 #define FASTRPC_BUILD_SCALARS(attr, method, in, out, oin, oout)  \
55 				(((attr & 0x07) << 29) |		\
56 				((method & 0x1f) << 24) |	\
57 				((in & 0xff) << 16) |		\
58 				((out & 0xff) <<  8) |		\
59 				((oin & 0x0f) <<  4) |		\
60 				(oout & 0x0f))
61 
62 #define FASTRPC_SCALARS(method, in, out) \
63 		FASTRPC_BUILD_SCALARS(0, method, in, out, 0, 0)
64 
65 #define FASTRPC_CREATE_PROCESS_NARGS	6
66 /* Remote Method id table */
67 #define FASTRPC_RMID_INIT_ATTACH	0
68 #define FASTRPC_RMID_INIT_RELEASE	1
69 #define FASTRPC_RMID_INIT_CREATE	6
70 #define FASTRPC_RMID_INIT_CREATE_ATTR	7
71 #define FASTRPC_RMID_INIT_CREATE_STATIC	8
72 
73 #define miscdev_to_cctx(d) container_of(d, struct fastrpc_channel_ctx, miscdev)
74 
75 static const char *domains[FASTRPC_DEV_MAX] = { "adsp", "mdsp",
76 						"sdsp", "cdsp"};
77 struct fastrpc_phy_page {
78 	u64 addr;		/* physical address */
79 	u64 size;		/* size of contiguous region */
80 };
81 
82 struct fastrpc_invoke_buf {
83 	u32 num;		/* number of contiguous regions */
84 	u32 pgidx;		/* index to start of contiguous region */
85 };
86 
87 struct fastrpc_remote_arg {
88 	u64 pv;
89 	u64 len;
90 };
91 
92 struct fastrpc_msg {
93 	int pid;		/* process group id */
94 	int tid;		/* thread id */
95 	u64 ctx;		/* invoke caller context */
96 	u32 handle;	/* handle to invoke */
97 	u32 sc;		/* scalars structure describing the data */
98 	u64 addr;		/* physical address */
99 	u64 size;		/* size of contiguous region */
100 };
101 
102 struct fastrpc_invoke_rsp {
103 	u64 ctx;		/* invoke caller context */
104 	int retval;		/* invoke return value */
105 };
106 
107 struct fastrpc_buf_overlap {
108 	u64 start;
109 	u64 end;
110 	int raix;
111 	u64 mstart;
112 	u64 mend;
113 	u64 offset;
114 };
115 
116 struct fastrpc_buf {
117 	struct fastrpc_user *fl;
118 	struct dma_buf *dmabuf;
119 	struct device *dev;
120 	void *virt;
121 	u64 phys;
122 	u64 size;
123 	/* Lock for dma buf attachments */
124 	struct mutex lock;
125 	struct list_head attachments;
126 };
127 
128 struct fastrpc_dma_buf_attachment {
129 	struct device *dev;
130 	struct sg_table sgt;
131 	struct list_head node;
132 };
133 
134 struct fastrpc_map {
135 	struct list_head node;
136 	struct fastrpc_user *fl;
137 	int fd;
138 	struct dma_buf *buf;
139 	struct sg_table *table;
140 	struct dma_buf_attachment *attach;
141 	u64 phys;
142 	u64 size;
143 	void *va;
144 	u64 len;
145 	struct kref refcount;
146 };
147 
148 struct fastrpc_invoke_ctx {
149 	int nscalars;
150 	int nbufs;
151 	int retval;
152 	int pid;
153 	int tgid;
154 	u32 sc;
155 	u32 *crc;
156 	u64 ctxid;
157 	u64 msg_sz;
158 	struct kref refcount;
159 	struct list_head node; /* list of ctxs */
160 	struct completion work;
161 	struct work_struct put_work;
162 	struct fastrpc_msg msg;
163 	struct fastrpc_user *fl;
164 	struct fastrpc_remote_arg *rpra;
165 	struct fastrpc_map **maps;
166 	struct fastrpc_buf *buf;
167 	struct fastrpc_invoke_args *args;
168 	struct fastrpc_buf_overlap *olaps;
169 	struct fastrpc_channel_ctx *cctx;
170 };
171 
172 struct fastrpc_session_ctx {
173 	struct device *dev;
174 	int sid;
175 	bool used;
176 	bool valid;
177 };
178 
179 struct fastrpc_channel_ctx {
180 	int domain_id;
181 	int sesscount;
182 	struct rpmsg_device *rpdev;
183 	struct fastrpc_session_ctx session[FASTRPC_MAX_SESSIONS];
184 	spinlock_t lock;
185 	struct idr ctx_idr;
186 	struct list_head users;
187 	struct miscdevice miscdev;
188 	struct kref refcount;
189 };
190 
191 struct fastrpc_user {
192 	struct list_head user;
193 	struct list_head maps;
194 	struct list_head pending;
195 
196 	struct fastrpc_channel_ctx *cctx;
197 	struct fastrpc_session_ctx *sctx;
198 	struct fastrpc_buf *init_mem;
199 
200 	int tgid;
201 	int pd;
202 	/* Lock for lists */
203 	spinlock_t lock;
204 	/* lock for allocations */
205 	struct mutex mutex;
206 };
207 
208 static void fastrpc_free_map(struct kref *ref)
209 {
210 	struct fastrpc_map *map;
211 
212 	map = container_of(ref, struct fastrpc_map, refcount);
213 
214 	if (map->table) {
215 		dma_buf_unmap_attachment(map->attach, map->table,
216 					 DMA_BIDIRECTIONAL);
217 		dma_buf_detach(map->buf, map->attach);
218 		dma_buf_put(map->buf);
219 	}
220 
221 	kfree(map);
222 }
223 
224 static void fastrpc_map_put(struct fastrpc_map *map)
225 {
226 	if (map)
227 		kref_put(&map->refcount, fastrpc_free_map);
228 }
229 
230 static void fastrpc_map_get(struct fastrpc_map *map)
231 {
232 	if (map)
233 		kref_get(&map->refcount);
234 }
235 
236 static int fastrpc_map_find(struct fastrpc_user *fl, int fd,
237 			    struct fastrpc_map **ppmap)
238 {
239 	struct fastrpc_map *map = NULL;
240 
241 	mutex_lock(&fl->mutex);
242 	list_for_each_entry(map, &fl->maps, node) {
243 		if (map->fd == fd) {
244 			fastrpc_map_get(map);
245 			*ppmap = map;
246 			mutex_unlock(&fl->mutex);
247 			return 0;
248 		}
249 	}
250 	mutex_unlock(&fl->mutex);
251 
252 	return -ENOENT;
253 }
254 
255 static void fastrpc_buf_free(struct fastrpc_buf *buf)
256 {
257 	dma_free_coherent(buf->dev, buf->size, buf->virt,
258 			  FASTRPC_PHYS(buf->phys));
259 	kfree(buf);
260 }
261 
262 static int fastrpc_buf_alloc(struct fastrpc_user *fl, struct device *dev,
263 			     u64 size, struct fastrpc_buf **obuf)
264 {
265 	struct fastrpc_buf *buf;
266 
267 	buf = kzalloc(sizeof(*buf), GFP_KERNEL);
268 	if (!buf)
269 		return -ENOMEM;
270 
271 	INIT_LIST_HEAD(&buf->attachments);
272 	mutex_init(&buf->lock);
273 
274 	buf->fl = fl;
275 	buf->virt = NULL;
276 	buf->phys = 0;
277 	buf->size = size;
278 	buf->dev = dev;
279 
280 	buf->virt = dma_alloc_coherent(dev, buf->size, (dma_addr_t *)&buf->phys,
281 				       GFP_KERNEL);
282 	if (!buf->virt) {
283 		mutex_destroy(&buf->lock);
284 		kfree(buf);
285 		return -ENOMEM;
286 	}
287 
288 	if (fl->sctx && fl->sctx->sid)
289 		buf->phys += ((u64)fl->sctx->sid << 32);
290 
291 	*obuf = buf;
292 
293 	return 0;
294 }
295 
296 static void fastrpc_channel_ctx_free(struct kref *ref)
297 {
298 	struct fastrpc_channel_ctx *cctx;
299 
300 	cctx = container_of(ref, struct fastrpc_channel_ctx, refcount);
301 
302 	kfree(cctx);
303 }
304 
305 static void fastrpc_channel_ctx_get(struct fastrpc_channel_ctx *cctx)
306 {
307 	kref_get(&cctx->refcount);
308 }
309 
310 static void fastrpc_channel_ctx_put(struct fastrpc_channel_ctx *cctx)
311 {
312 	kref_put(&cctx->refcount, fastrpc_channel_ctx_free);
313 }
314 
315 static void fastrpc_context_free(struct kref *ref)
316 {
317 	struct fastrpc_invoke_ctx *ctx;
318 	struct fastrpc_channel_ctx *cctx;
319 	unsigned long flags;
320 	int i;
321 
322 	ctx = container_of(ref, struct fastrpc_invoke_ctx, refcount);
323 	cctx = ctx->cctx;
324 
325 	for (i = 0; i < ctx->nscalars; i++)
326 		fastrpc_map_put(ctx->maps[i]);
327 
328 	if (ctx->buf)
329 		fastrpc_buf_free(ctx->buf);
330 
331 	spin_lock_irqsave(&cctx->lock, flags);
332 	idr_remove(&cctx->ctx_idr, ctx->ctxid >> 4);
333 	spin_unlock_irqrestore(&cctx->lock, flags);
334 
335 	kfree(ctx->maps);
336 	kfree(ctx->olaps);
337 	kfree(ctx);
338 
339 	fastrpc_channel_ctx_put(cctx);
340 }
341 
342 static void fastrpc_context_get(struct fastrpc_invoke_ctx *ctx)
343 {
344 	kref_get(&ctx->refcount);
345 }
346 
347 static void fastrpc_context_put(struct fastrpc_invoke_ctx *ctx)
348 {
349 	kref_put(&ctx->refcount, fastrpc_context_free);
350 }
351 
352 static void fastrpc_context_put_wq(struct work_struct *work)
353 {
354 	struct fastrpc_invoke_ctx *ctx =
355 			container_of(work, struct fastrpc_invoke_ctx, put_work);
356 
357 	fastrpc_context_put(ctx);
358 }
359 
360 #define CMP(aa, bb) ((aa) == (bb) ? 0 : (aa) < (bb) ? -1 : 1)
361 static int olaps_cmp(const void *a, const void *b)
362 {
363 	struct fastrpc_buf_overlap *pa = (struct fastrpc_buf_overlap *)a;
364 	struct fastrpc_buf_overlap *pb = (struct fastrpc_buf_overlap *)b;
365 	/* sort with lowest starting buffer first */
366 	int st = CMP(pa->start, pb->start);
367 	/* sort with highest ending buffer first */
368 	int ed = CMP(pb->end, pa->end);
369 
370 	return st == 0 ? ed : st;
371 }
372 
373 static void fastrpc_get_buff_overlaps(struct fastrpc_invoke_ctx *ctx)
374 {
375 	u64 max_end = 0;
376 	int i;
377 
378 	for (i = 0; i < ctx->nbufs; ++i) {
379 		ctx->olaps[i].start = ctx->args[i].ptr;
380 		ctx->olaps[i].end = ctx->olaps[i].start + ctx->args[i].length;
381 		ctx->olaps[i].raix = i;
382 	}
383 
384 	sort(ctx->olaps, ctx->nbufs, sizeof(*ctx->olaps), olaps_cmp, NULL);
385 
386 	for (i = 0; i < ctx->nbufs; ++i) {
387 		/* Falling inside previous range */
388 		if (ctx->olaps[i].start < max_end) {
389 			ctx->olaps[i].mstart = max_end;
390 			ctx->olaps[i].mend = ctx->olaps[i].end;
391 			ctx->olaps[i].offset = max_end - ctx->olaps[i].start;
392 
393 			if (ctx->olaps[i].end > max_end) {
394 				max_end = ctx->olaps[i].end;
395 			} else {
396 				ctx->olaps[i].mend = 0;
397 				ctx->olaps[i].mstart = 0;
398 			}
399 
400 		} else  {
401 			ctx->olaps[i].mend = ctx->olaps[i].end;
402 			ctx->olaps[i].mstart = ctx->olaps[i].start;
403 			ctx->olaps[i].offset = 0;
404 			max_end = ctx->olaps[i].end;
405 		}
406 	}
407 }
408 
409 static struct fastrpc_invoke_ctx *fastrpc_context_alloc(
410 			struct fastrpc_user *user, u32 kernel, u32 sc,
411 			struct fastrpc_invoke_args *args)
412 {
413 	struct fastrpc_channel_ctx *cctx = user->cctx;
414 	struct fastrpc_invoke_ctx *ctx = NULL;
415 	unsigned long flags;
416 	int ret;
417 
418 	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
419 	if (!ctx)
420 		return ERR_PTR(-ENOMEM);
421 
422 	INIT_LIST_HEAD(&ctx->node);
423 	ctx->fl = user;
424 	ctx->nscalars = REMOTE_SCALARS_LENGTH(sc);
425 	ctx->nbufs = REMOTE_SCALARS_INBUFS(sc) +
426 		     REMOTE_SCALARS_OUTBUFS(sc);
427 
428 	if (ctx->nscalars) {
429 		ctx->maps = kcalloc(ctx->nscalars,
430 				    sizeof(*ctx->maps), GFP_KERNEL);
431 		if (!ctx->maps) {
432 			kfree(ctx);
433 			return ERR_PTR(-ENOMEM);
434 		}
435 		ctx->olaps = kcalloc(ctx->nscalars,
436 				    sizeof(*ctx->olaps), GFP_KERNEL);
437 		if (!ctx->olaps) {
438 			kfree(ctx->maps);
439 			kfree(ctx);
440 			return ERR_PTR(-ENOMEM);
441 		}
442 		ctx->args = args;
443 		fastrpc_get_buff_overlaps(ctx);
444 	}
445 
446 	/* Released in fastrpc_context_put() */
447 	fastrpc_channel_ctx_get(cctx);
448 
449 	ctx->sc = sc;
450 	ctx->retval = -1;
451 	ctx->pid = current->pid;
452 	ctx->tgid = user->tgid;
453 	ctx->cctx = cctx;
454 	init_completion(&ctx->work);
455 	INIT_WORK(&ctx->put_work, fastrpc_context_put_wq);
456 
457 	spin_lock(&user->lock);
458 	list_add_tail(&ctx->node, &user->pending);
459 	spin_unlock(&user->lock);
460 
461 	spin_lock_irqsave(&cctx->lock, flags);
462 	ret = idr_alloc_cyclic(&cctx->ctx_idr, ctx, 1,
463 			       FASTRPC_CTX_MAX, GFP_ATOMIC);
464 	if (ret < 0) {
465 		spin_unlock_irqrestore(&cctx->lock, flags);
466 		goto err_idr;
467 	}
468 	ctx->ctxid = ret << 4;
469 	spin_unlock_irqrestore(&cctx->lock, flags);
470 
471 	kref_init(&ctx->refcount);
472 
473 	return ctx;
474 err_idr:
475 	spin_lock(&user->lock);
476 	list_del(&ctx->node);
477 	spin_unlock(&user->lock);
478 	fastrpc_channel_ctx_put(cctx);
479 	kfree(ctx->maps);
480 	kfree(ctx->olaps);
481 	kfree(ctx);
482 
483 	return ERR_PTR(ret);
484 }
485 
486 static struct sg_table *
487 fastrpc_map_dma_buf(struct dma_buf_attachment *attachment,
488 		    enum dma_data_direction dir)
489 {
490 	struct fastrpc_dma_buf_attachment *a = attachment->priv;
491 	struct sg_table *table;
492 
493 	table = &a->sgt;
494 
495 	if (!dma_map_sg(attachment->dev, table->sgl, table->nents, dir))
496 		return ERR_PTR(-ENOMEM);
497 
498 	return table;
499 }
500 
501 static void fastrpc_unmap_dma_buf(struct dma_buf_attachment *attach,
502 				  struct sg_table *table,
503 				  enum dma_data_direction dir)
504 {
505 	dma_unmap_sg(attach->dev, table->sgl, table->nents, dir);
506 }
507 
508 static void fastrpc_release(struct dma_buf *dmabuf)
509 {
510 	struct fastrpc_buf *buffer = dmabuf->priv;
511 
512 	fastrpc_buf_free(buffer);
513 }
514 
515 static int fastrpc_dma_buf_attach(struct dma_buf *dmabuf,
516 				  struct dma_buf_attachment *attachment)
517 {
518 	struct fastrpc_dma_buf_attachment *a;
519 	struct fastrpc_buf *buffer = dmabuf->priv;
520 	int ret;
521 
522 	a = kzalloc(sizeof(*a), GFP_KERNEL);
523 	if (!a)
524 		return -ENOMEM;
525 
526 	ret = dma_get_sgtable(buffer->dev, &a->sgt, buffer->virt,
527 			      FASTRPC_PHYS(buffer->phys), buffer->size);
528 	if (ret < 0) {
529 		dev_err(buffer->dev, "failed to get scatterlist from DMA API\n");
530 		return -EINVAL;
531 	}
532 
533 	a->dev = attachment->dev;
534 	INIT_LIST_HEAD(&a->node);
535 	attachment->priv = a;
536 
537 	mutex_lock(&buffer->lock);
538 	list_add(&a->node, &buffer->attachments);
539 	mutex_unlock(&buffer->lock);
540 
541 	return 0;
542 }
543 
544 static void fastrpc_dma_buf_detatch(struct dma_buf *dmabuf,
545 				    struct dma_buf_attachment *attachment)
546 {
547 	struct fastrpc_dma_buf_attachment *a = attachment->priv;
548 	struct fastrpc_buf *buffer = dmabuf->priv;
549 
550 	mutex_lock(&buffer->lock);
551 	list_del(&a->node);
552 	mutex_unlock(&buffer->lock);
553 	sg_free_table(&a->sgt);
554 	kfree(a);
555 }
556 
557 static void *fastrpc_kmap(struct dma_buf *dmabuf, unsigned long pgnum)
558 {
559 	struct fastrpc_buf *buf = dmabuf->priv;
560 
561 	return buf->virt ? buf->virt + pgnum * PAGE_SIZE : NULL;
562 }
563 
564 static void *fastrpc_vmap(struct dma_buf *dmabuf)
565 {
566 	struct fastrpc_buf *buf = dmabuf->priv;
567 
568 	return buf->virt;
569 }
570 
571 static int fastrpc_mmap(struct dma_buf *dmabuf,
572 			struct vm_area_struct *vma)
573 {
574 	struct fastrpc_buf *buf = dmabuf->priv;
575 	size_t size = vma->vm_end - vma->vm_start;
576 
577 	return dma_mmap_coherent(buf->dev, vma, buf->virt,
578 				 FASTRPC_PHYS(buf->phys), size);
579 }
580 
581 static const struct dma_buf_ops fastrpc_dma_buf_ops = {
582 	.attach = fastrpc_dma_buf_attach,
583 	.detach = fastrpc_dma_buf_detatch,
584 	.map_dma_buf = fastrpc_map_dma_buf,
585 	.unmap_dma_buf = fastrpc_unmap_dma_buf,
586 	.mmap = fastrpc_mmap,
587 	.map = fastrpc_kmap,
588 	.vmap = fastrpc_vmap,
589 	.release = fastrpc_release,
590 };
591 
592 static int fastrpc_map_create(struct fastrpc_user *fl, int fd,
593 			      u64 len, struct fastrpc_map **ppmap)
594 {
595 	struct fastrpc_session_ctx *sess = fl->sctx;
596 	struct fastrpc_map *map = NULL;
597 	int err = 0;
598 
599 	if (!fastrpc_map_find(fl, fd, ppmap))
600 		return 0;
601 
602 	map = kzalloc(sizeof(*map), GFP_KERNEL);
603 	if (!map)
604 		return -ENOMEM;
605 
606 	INIT_LIST_HEAD(&map->node);
607 	map->fl = fl;
608 	map->fd = fd;
609 	map->buf = dma_buf_get(fd);
610 	if (IS_ERR(map->buf)) {
611 		err = PTR_ERR(map->buf);
612 		goto get_err;
613 	}
614 
615 	map->attach = dma_buf_attach(map->buf, sess->dev);
616 	if (IS_ERR(map->attach)) {
617 		dev_err(sess->dev, "Failed to attach dmabuf\n");
618 		err = PTR_ERR(map->attach);
619 		goto attach_err;
620 	}
621 
622 	map->table = dma_buf_map_attachment(map->attach, DMA_BIDIRECTIONAL);
623 	if (IS_ERR(map->table)) {
624 		err = PTR_ERR(map->table);
625 		goto map_err;
626 	}
627 
628 	map->phys = sg_dma_address(map->table->sgl);
629 	map->phys += ((u64)fl->sctx->sid << 32);
630 	map->size = len;
631 	map->va = sg_virt(map->table->sgl);
632 	map->len = len;
633 	kref_init(&map->refcount);
634 
635 	spin_lock(&fl->lock);
636 	list_add_tail(&map->node, &fl->maps);
637 	spin_unlock(&fl->lock);
638 	*ppmap = map;
639 
640 	return 0;
641 
642 map_err:
643 	dma_buf_detach(map->buf, map->attach);
644 attach_err:
645 	dma_buf_put(map->buf);
646 get_err:
647 	kfree(map);
648 
649 	return err;
650 }
651 
652 /*
653  * Fastrpc payload buffer with metadata looks like:
654  *
655  * >>>>>>  START of METADATA <<<<<<<<<
656  * +---------------------------------+
657  * |           Arguments             |
658  * | type:(struct fastrpc_remote_arg)|
659  * |             (0 - N)             |
660  * +---------------------------------+
661  * |         Invoke Buffer list      |
662  * | type:(struct fastrpc_invoke_buf)|
663  * |           (0 - N)               |
664  * +---------------------------------+
665  * |         Page info list          |
666  * | type:(struct fastrpc_phy_page)  |
667  * |             (0 - N)             |
668  * +---------------------------------+
669  * |         Optional info           |
670  * |(can be specific to SoC/Firmware)|
671  * +---------------------------------+
672  * >>>>>>>>  END of METADATA <<<<<<<<<
673  * +---------------------------------+
674  * |         Inline ARGS             |
675  * |            (0-N)                |
676  * +---------------------------------+
677  */
678 
679 static int fastrpc_get_meta_size(struct fastrpc_invoke_ctx *ctx)
680 {
681 	int size = 0;
682 
683 	size = (sizeof(struct fastrpc_remote_arg) +
684 		sizeof(struct fastrpc_invoke_buf) +
685 		sizeof(struct fastrpc_phy_page)) * ctx->nscalars +
686 		sizeof(u64) * FASTRPC_MAX_FDLIST +
687 		sizeof(u32) * FASTRPC_MAX_CRCLIST;
688 
689 	return size;
690 }
691 
692 static u64 fastrpc_get_payload_size(struct fastrpc_invoke_ctx *ctx, int metalen)
693 {
694 	u64 size = 0;
695 	int i;
696 
697 	size = ALIGN(metalen, FASTRPC_ALIGN);
698 	for (i = 0; i < ctx->nscalars; i++) {
699 		if (ctx->args[i].fd == 0 || ctx->args[i].fd == -1) {
700 
701 			if (ctx->olaps[i].offset == 0)
702 				size = ALIGN(size, FASTRPC_ALIGN);
703 
704 			size += (ctx->olaps[i].mend - ctx->olaps[i].mstart);
705 		}
706 	}
707 
708 	return size;
709 }
710 
711 static int fastrpc_create_maps(struct fastrpc_invoke_ctx *ctx)
712 {
713 	struct device *dev = ctx->fl->sctx->dev;
714 	int i, err;
715 
716 	for (i = 0; i < ctx->nscalars; ++i) {
717 		/* Make sure reserved field is set to 0 */
718 		if (ctx->args[i].reserved)
719 			return -EINVAL;
720 
721 		if (ctx->args[i].fd == 0 || ctx->args[i].fd == -1 ||
722 		    ctx->args[i].length == 0)
723 			continue;
724 
725 		err = fastrpc_map_create(ctx->fl, ctx->args[i].fd,
726 					 ctx->args[i].length, &ctx->maps[i]);
727 		if (err) {
728 			dev_err(dev, "Error Creating map %d\n", err);
729 			return -EINVAL;
730 		}
731 
732 	}
733 	return 0;
734 }
735 
736 static int fastrpc_get_args(u32 kernel, struct fastrpc_invoke_ctx *ctx)
737 {
738 	struct device *dev = ctx->fl->sctx->dev;
739 	struct fastrpc_remote_arg *rpra;
740 	struct fastrpc_invoke_buf *list;
741 	struct fastrpc_phy_page *pages;
742 	int inbufs, i, oix, err = 0;
743 	u64 len, rlen, pkt_size;
744 	u64 pg_start, pg_end;
745 	uintptr_t args;
746 	int metalen;
747 
748 	inbufs = REMOTE_SCALARS_INBUFS(ctx->sc);
749 	metalen = fastrpc_get_meta_size(ctx);
750 	pkt_size = fastrpc_get_payload_size(ctx, metalen);
751 
752 	err = fastrpc_create_maps(ctx);
753 	if (err)
754 		return err;
755 
756 	ctx->msg_sz = pkt_size;
757 
758 	err = fastrpc_buf_alloc(ctx->fl, dev, pkt_size, &ctx->buf);
759 	if (err)
760 		return err;
761 
762 	rpra = ctx->buf->virt;
763 	list = ctx->buf->virt + ctx->nscalars * sizeof(*rpra);
764 	pages = ctx->buf->virt + ctx->nscalars * (sizeof(*list) +
765 		sizeof(*rpra));
766 	args = (uintptr_t)ctx->buf->virt + metalen;
767 	rlen = pkt_size - metalen;
768 	ctx->rpra = rpra;
769 
770 	for (oix = 0; oix < ctx->nbufs; ++oix) {
771 		int mlen;
772 
773 		i = ctx->olaps[oix].raix;
774 		len = ctx->args[i].length;
775 
776 		rpra[i].pv = 0;
777 		rpra[i].len = len;
778 		list[i].num = len ? 1 : 0;
779 		list[i].pgidx = i;
780 
781 		if (!len)
782 			continue;
783 
784 		if (ctx->maps[i]) {
785 			struct vm_area_struct *vma = NULL;
786 
787 			rpra[i].pv = (u64) ctx->args[i].ptr;
788 			pages[i].addr = ctx->maps[i]->phys;
789 
790 			vma = find_vma(current->mm, ctx->args[i].ptr);
791 			if (vma)
792 				pages[i].addr += ctx->args[i].ptr -
793 						 vma->vm_start;
794 
795 			pg_start = (ctx->args[i].ptr & PAGE_MASK) >> PAGE_SHIFT;
796 			pg_end = ((ctx->args[i].ptr + len - 1) & PAGE_MASK) >>
797 				  PAGE_SHIFT;
798 			pages[i].size = (pg_end - pg_start + 1) * PAGE_SIZE;
799 
800 		} else {
801 
802 			if (ctx->olaps[oix].offset == 0) {
803 				rlen -= ALIGN(args, FASTRPC_ALIGN) - args;
804 				args = ALIGN(args, FASTRPC_ALIGN);
805 			}
806 
807 			mlen = ctx->olaps[oix].mend - ctx->olaps[oix].mstart;
808 
809 			if (rlen < mlen)
810 				goto bail;
811 
812 			rpra[i].pv = args - ctx->olaps[oix].offset;
813 			pages[i].addr = ctx->buf->phys -
814 					ctx->olaps[oix].offset +
815 					(pkt_size - rlen);
816 			pages[i].addr = pages[i].addr &	PAGE_MASK;
817 
818 			pg_start = (args & PAGE_MASK) >> PAGE_SHIFT;
819 			pg_end = ((args + len - 1) & PAGE_MASK) >> PAGE_SHIFT;
820 			pages[i].size = (pg_end - pg_start + 1) * PAGE_SIZE;
821 			args = args + mlen;
822 			rlen -= mlen;
823 		}
824 
825 		if (i < inbufs && !ctx->maps[i]) {
826 			void *dst = (void *)(uintptr_t)rpra[i].pv;
827 			void *src = (void *)(uintptr_t)ctx->args[i].ptr;
828 
829 			if (!kernel) {
830 				if (copy_from_user(dst, (void __user *)src,
831 						   len)) {
832 					err = -EFAULT;
833 					goto bail;
834 				}
835 			} else {
836 				memcpy(dst, src, len);
837 			}
838 		}
839 	}
840 
841 	for (i = ctx->nbufs; i < ctx->nscalars; ++i) {
842 		rpra[i].pv = (u64) ctx->args[i].ptr;
843 		rpra[i].len = ctx->args[i].length;
844 		list[i].num = ctx->args[i].length ? 1 : 0;
845 		list[i].pgidx = i;
846 		pages[i].addr = ctx->maps[i]->phys;
847 		pages[i].size = ctx->maps[i]->size;
848 	}
849 
850 bail:
851 	if (err)
852 		dev_err(dev, "Error: get invoke args failed:%d\n", err);
853 
854 	return err;
855 }
856 
857 static int fastrpc_put_args(struct fastrpc_invoke_ctx *ctx,
858 			    u32 kernel)
859 {
860 	struct fastrpc_remote_arg *rpra = ctx->rpra;
861 	int i, inbufs;
862 
863 	inbufs = REMOTE_SCALARS_INBUFS(ctx->sc);
864 
865 	for (i = inbufs; i < ctx->nbufs; ++i) {
866 		void *src = (void *)(uintptr_t)rpra[i].pv;
867 		void *dst = (void *)(uintptr_t)ctx->args[i].ptr;
868 		u64 len = rpra[i].len;
869 
870 		if (!kernel) {
871 			if (copy_to_user((void __user *)dst, src, len))
872 				return -EFAULT;
873 		} else {
874 			memcpy(dst, src, len);
875 		}
876 	}
877 
878 	return 0;
879 }
880 
881 static int fastrpc_invoke_send(struct fastrpc_session_ctx *sctx,
882 			       struct fastrpc_invoke_ctx *ctx,
883 			       u32 kernel, uint32_t handle)
884 {
885 	struct fastrpc_channel_ctx *cctx;
886 	struct fastrpc_user *fl = ctx->fl;
887 	struct fastrpc_msg *msg = &ctx->msg;
888 
889 	cctx = fl->cctx;
890 	msg->pid = fl->tgid;
891 	msg->tid = current->pid;
892 
893 	if (kernel)
894 		msg->pid = 0;
895 
896 	msg->ctx = ctx->ctxid | fl->pd;
897 	msg->handle = handle;
898 	msg->sc = ctx->sc;
899 	msg->addr = ctx->buf ? ctx->buf->phys : 0;
900 	msg->size = roundup(ctx->msg_sz, PAGE_SIZE);
901 	fastrpc_context_get(ctx);
902 
903 	return rpmsg_send(cctx->rpdev->ept, (void *)msg, sizeof(*msg));
904 }
905 
906 static int fastrpc_internal_invoke(struct fastrpc_user *fl,  u32 kernel,
907 				   u32 handle, u32 sc,
908 				   struct fastrpc_invoke_args *args)
909 {
910 	struct fastrpc_invoke_ctx *ctx = NULL;
911 	int err = 0;
912 
913 	if (!fl->sctx)
914 		return -EINVAL;
915 
916 	if (!fl->cctx->rpdev)
917 		return -EPIPE;
918 
919 	ctx = fastrpc_context_alloc(fl, kernel, sc, args);
920 	if (IS_ERR(ctx))
921 		return PTR_ERR(ctx);
922 
923 	if (ctx->nscalars) {
924 		err = fastrpc_get_args(kernel, ctx);
925 		if (err)
926 			goto bail;
927 	}
928 
929 	/* make sure that all CPU memory writes are seen by DSP */
930 	dma_wmb();
931 	/* Send invoke buffer to remote dsp */
932 	err = fastrpc_invoke_send(fl->sctx, ctx, kernel, handle);
933 	if (err)
934 		goto bail;
935 
936 	/* Wait for remote dsp to respond or time out */
937 	err = wait_for_completion_interruptible(&ctx->work);
938 	if (err)
939 		goto bail;
940 
941 	/* Check the response from remote dsp */
942 	err = ctx->retval;
943 	if (err)
944 		goto bail;
945 
946 	if (ctx->nscalars) {
947 		/* make sure that all memory writes by DSP are seen by CPU */
948 		dma_rmb();
949 		/* populate all the output buffers with results */
950 		err = fastrpc_put_args(ctx, kernel);
951 		if (err)
952 			goto bail;
953 	}
954 
955 bail:
956 	/* We are done with this compute context, remove it from pending list */
957 	spin_lock(&fl->lock);
958 	list_del(&ctx->node);
959 	spin_unlock(&fl->lock);
960 	fastrpc_context_put(ctx);
961 
962 	if (err)
963 		dev_dbg(fl->sctx->dev, "Error: Invoke Failed %d\n", err);
964 
965 	return err;
966 }
967 
968 static int fastrpc_init_create_process(struct fastrpc_user *fl,
969 					char __user *argp)
970 {
971 	struct fastrpc_init_create init;
972 	struct fastrpc_invoke_args *args;
973 	struct fastrpc_phy_page pages[1];
974 	struct fastrpc_map *map = NULL;
975 	struct fastrpc_buf *imem = NULL;
976 	int memlen;
977 	int err;
978 	struct {
979 		int pgid;
980 		u32 namelen;
981 		u32 filelen;
982 		u32 pageslen;
983 		u32 attrs;
984 		u32 siglen;
985 	} inbuf;
986 	u32 sc;
987 
988 	args = kcalloc(FASTRPC_CREATE_PROCESS_NARGS, sizeof(*args), GFP_KERNEL);
989 	if (!args)
990 		return -ENOMEM;
991 
992 	if (copy_from_user(&init, argp, sizeof(init))) {
993 		err = -EFAULT;
994 		goto err;
995 	}
996 
997 	if (init.filelen > INIT_FILELEN_MAX) {
998 		err = -EINVAL;
999 		goto err;
1000 	}
1001 
1002 	inbuf.pgid = fl->tgid;
1003 	inbuf.namelen = strlen(current->comm) + 1;
1004 	inbuf.filelen = init.filelen;
1005 	inbuf.pageslen = 1;
1006 	inbuf.attrs = init.attrs;
1007 	inbuf.siglen = init.siglen;
1008 	fl->pd = 1;
1009 
1010 	if (init.filelen && init.filefd) {
1011 		err = fastrpc_map_create(fl, init.filefd, init.filelen, &map);
1012 		if (err)
1013 			goto err;
1014 	}
1015 
1016 	memlen = ALIGN(max(INIT_FILELEN_MAX, (int)init.filelen * 4),
1017 		       1024 * 1024);
1018 	err = fastrpc_buf_alloc(fl, fl->sctx->dev, memlen,
1019 				&imem);
1020 	if (err)
1021 		goto err_alloc;
1022 
1023 	fl->init_mem = imem;
1024 	args[0].ptr = (u64)(uintptr_t)&inbuf;
1025 	args[0].length = sizeof(inbuf);
1026 	args[0].fd = -1;
1027 
1028 	args[1].ptr = (u64)(uintptr_t)current->comm;
1029 	args[1].length = inbuf.namelen;
1030 	args[1].fd = -1;
1031 
1032 	args[2].ptr = (u64) init.file;
1033 	args[2].length = inbuf.filelen;
1034 	args[2].fd = init.filefd;
1035 
1036 	pages[0].addr = imem->phys;
1037 	pages[0].size = imem->size;
1038 
1039 	args[3].ptr = (u64)(uintptr_t) pages;
1040 	args[3].length = 1 * sizeof(*pages);
1041 	args[3].fd = -1;
1042 
1043 	args[4].ptr = (u64)(uintptr_t)&inbuf.attrs;
1044 	args[4].length = sizeof(inbuf.attrs);
1045 	args[4].fd = -1;
1046 
1047 	args[5].ptr = (u64)(uintptr_t) &inbuf.siglen;
1048 	args[5].length = sizeof(inbuf.siglen);
1049 	args[5].fd = -1;
1050 
1051 	sc = FASTRPC_SCALARS(FASTRPC_RMID_INIT_CREATE, 4, 0);
1052 	if (init.attrs)
1053 		sc = FASTRPC_SCALARS(FASTRPC_RMID_INIT_CREATE_ATTR, 6, 0);
1054 
1055 	err = fastrpc_internal_invoke(fl, true, FASTRPC_INIT_HANDLE,
1056 				      sc, args);
1057 	if (err)
1058 		goto err_invoke;
1059 
1060 	kfree(args);
1061 
1062 	return 0;
1063 
1064 err_invoke:
1065 	fl->init_mem = NULL;
1066 	fastrpc_buf_free(imem);
1067 err_alloc:
1068 	if (map) {
1069 		spin_lock(&fl->lock);
1070 		list_del(&map->node);
1071 		spin_unlock(&fl->lock);
1072 		fastrpc_map_put(map);
1073 	}
1074 err:
1075 	kfree(args);
1076 
1077 	return err;
1078 }
1079 
1080 static struct fastrpc_session_ctx *fastrpc_session_alloc(
1081 					struct fastrpc_channel_ctx *cctx)
1082 {
1083 	struct fastrpc_session_ctx *session = NULL;
1084 	unsigned long flags;
1085 	int i;
1086 
1087 	spin_lock_irqsave(&cctx->lock, flags);
1088 	for (i = 0; i < cctx->sesscount; i++) {
1089 		if (!cctx->session[i].used && cctx->session[i].valid) {
1090 			cctx->session[i].used = true;
1091 			session = &cctx->session[i];
1092 			break;
1093 		}
1094 	}
1095 	spin_unlock_irqrestore(&cctx->lock, flags);
1096 
1097 	return session;
1098 }
1099 
1100 static void fastrpc_session_free(struct fastrpc_channel_ctx *cctx,
1101 				 struct fastrpc_session_ctx *session)
1102 {
1103 	unsigned long flags;
1104 
1105 	spin_lock_irqsave(&cctx->lock, flags);
1106 	session->used = false;
1107 	spin_unlock_irqrestore(&cctx->lock, flags);
1108 }
1109 
1110 static int fastrpc_release_current_dsp_process(struct fastrpc_user *fl)
1111 {
1112 	struct fastrpc_invoke_args args[1];
1113 	int tgid = 0;
1114 	u32 sc;
1115 
1116 	tgid = fl->tgid;
1117 	args[0].ptr = (u64)(uintptr_t) &tgid;
1118 	args[0].length = sizeof(tgid);
1119 	args[0].fd = -1;
1120 	args[0].reserved = 0;
1121 	sc = FASTRPC_SCALARS(FASTRPC_RMID_INIT_RELEASE, 1, 0);
1122 
1123 	return fastrpc_internal_invoke(fl, true, FASTRPC_INIT_HANDLE,
1124 				       sc, &args[0]);
1125 }
1126 
1127 static int fastrpc_device_release(struct inode *inode, struct file *file)
1128 {
1129 	struct fastrpc_user *fl = (struct fastrpc_user *)file->private_data;
1130 	struct fastrpc_channel_ctx *cctx = fl->cctx;
1131 	struct fastrpc_invoke_ctx *ctx, *n;
1132 	struct fastrpc_map *map, *m;
1133 	unsigned long flags;
1134 
1135 	fastrpc_release_current_dsp_process(fl);
1136 
1137 	spin_lock_irqsave(&cctx->lock, flags);
1138 	list_del(&fl->user);
1139 	spin_unlock_irqrestore(&cctx->lock, flags);
1140 
1141 	if (fl->init_mem)
1142 		fastrpc_buf_free(fl->init_mem);
1143 
1144 	list_for_each_entry_safe(ctx, n, &fl->pending, node) {
1145 		list_del(&ctx->node);
1146 		fastrpc_context_put(ctx);
1147 	}
1148 
1149 	list_for_each_entry_safe(map, m, &fl->maps, node) {
1150 		list_del(&map->node);
1151 		fastrpc_map_put(map);
1152 	}
1153 
1154 	fastrpc_session_free(cctx, fl->sctx);
1155 	fastrpc_channel_ctx_put(cctx);
1156 
1157 	mutex_destroy(&fl->mutex);
1158 	kfree(fl);
1159 	file->private_data = NULL;
1160 
1161 	return 0;
1162 }
1163 
1164 static int fastrpc_device_open(struct inode *inode, struct file *filp)
1165 {
1166 	struct fastrpc_channel_ctx *cctx = miscdev_to_cctx(filp->private_data);
1167 	struct fastrpc_user *fl = NULL;
1168 	unsigned long flags;
1169 
1170 	fl = kzalloc(sizeof(*fl), GFP_KERNEL);
1171 	if (!fl)
1172 		return -ENOMEM;
1173 
1174 	/* Released in fastrpc_device_release() */
1175 	fastrpc_channel_ctx_get(cctx);
1176 
1177 	filp->private_data = fl;
1178 	spin_lock_init(&fl->lock);
1179 	mutex_init(&fl->mutex);
1180 	INIT_LIST_HEAD(&fl->pending);
1181 	INIT_LIST_HEAD(&fl->maps);
1182 	INIT_LIST_HEAD(&fl->user);
1183 	fl->tgid = current->tgid;
1184 	fl->cctx = cctx;
1185 
1186 	fl->sctx = fastrpc_session_alloc(cctx);
1187 	if (!fl->sctx) {
1188 		dev_err(&cctx->rpdev->dev, "No session available\n");
1189 		mutex_destroy(&fl->mutex);
1190 		kfree(fl);
1191 
1192 		return -EBUSY;
1193 	}
1194 
1195 	spin_lock_irqsave(&cctx->lock, flags);
1196 	list_add_tail(&fl->user, &cctx->users);
1197 	spin_unlock_irqrestore(&cctx->lock, flags);
1198 
1199 	return 0;
1200 }
1201 
1202 static int fastrpc_dmabuf_alloc(struct fastrpc_user *fl, char __user *argp)
1203 {
1204 	struct fastrpc_alloc_dma_buf bp;
1205 	DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
1206 	struct fastrpc_buf *buf = NULL;
1207 	int err;
1208 
1209 	if (copy_from_user(&bp, argp, sizeof(bp)))
1210 		return -EFAULT;
1211 
1212 	err = fastrpc_buf_alloc(fl, fl->sctx->dev, bp.size, &buf);
1213 	if (err)
1214 		return err;
1215 	exp_info.ops = &fastrpc_dma_buf_ops;
1216 	exp_info.size = bp.size;
1217 	exp_info.flags = O_RDWR;
1218 	exp_info.priv = buf;
1219 	buf->dmabuf = dma_buf_export(&exp_info);
1220 	if (IS_ERR(buf->dmabuf)) {
1221 		err = PTR_ERR(buf->dmabuf);
1222 		fastrpc_buf_free(buf);
1223 		return err;
1224 	}
1225 
1226 	bp.fd = dma_buf_fd(buf->dmabuf, O_ACCMODE);
1227 	if (bp.fd < 0) {
1228 		dma_buf_put(buf->dmabuf);
1229 		return -EINVAL;
1230 	}
1231 
1232 	if (copy_to_user(argp, &bp, sizeof(bp))) {
1233 		dma_buf_put(buf->dmabuf);
1234 		return -EFAULT;
1235 	}
1236 
1237 	return 0;
1238 }
1239 
1240 static int fastrpc_init_attach(struct fastrpc_user *fl)
1241 {
1242 	struct fastrpc_invoke_args args[1];
1243 	int tgid = fl->tgid;
1244 	u32 sc;
1245 
1246 	args[0].ptr = (u64)(uintptr_t) &tgid;
1247 	args[0].length = sizeof(tgid);
1248 	args[0].fd = -1;
1249 	args[0].reserved = 0;
1250 	sc = FASTRPC_SCALARS(FASTRPC_RMID_INIT_ATTACH, 1, 0);
1251 	fl->pd = 0;
1252 
1253 	return fastrpc_internal_invoke(fl, true, FASTRPC_INIT_HANDLE,
1254 				       sc, &args[0]);
1255 }
1256 
1257 static int fastrpc_invoke(struct fastrpc_user *fl, char __user *argp)
1258 {
1259 	struct fastrpc_invoke_args *args = NULL;
1260 	struct fastrpc_invoke inv;
1261 	u32 nscalars;
1262 	int err;
1263 
1264 	if (copy_from_user(&inv, argp, sizeof(inv)))
1265 		return -EFAULT;
1266 
1267 	/* nscalars is truncated here to max supported value */
1268 	nscalars = REMOTE_SCALARS_LENGTH(inv.sc);
1269 	if (nscalars) {
1270 		args = kcalloc(nscalars, sizeof(*args), GFP_KERNEL);
1271 		if (!args)
1272 			return -ENOMEM;
1273 
1274 		if (copy_from_user(args, (void __user *)(uintptr_t)inv.args,
1275 				   nscalars * sizeof(*args))) {
1276 			kfree(args);
1277 			return -EFAULT;
1278 		}
1279 	}
1280 
1281 	err = fastrpc_internal_invoke(fl, false, inv.handle, inv.sc, args);
1282 	kfree(args);
1283 
1284 	return err;
1285 }
1286 
1287 static long fastrpc_device_ioctl(struct file *file, unsigned int cmd,
1288 				 unsigned long arg)
1289 {
1290 	struct fastrpc_user *fl = (struct fastrpc_user *)file->private_data;
1291 	char __user *argp = (char __user *)arg;
1292 	int err;
1293 
1294 	switch (cmd) {
1295 	case FASTRPC_IOCTL_INVOKE:
1296 		err = fastrpc_invoke(fl, argp);
1297 		break;
1298 	case FASTRPC_IOCTL_INIT_ATTACH:
1299 		err = fastrpc_init_attach(fl);
1300 		break;
1301 	case FASTRPC_IOCTL_INIT_CREATE:
1302 		err = fastrpc_init_create_process(fl, argp);
1303 		break;
1304 	case FASTRPC_IOCTL_ALLOC_DMA_BUFF:
1305 		err = fastrpc_dmabuf_alloc(fl, argp);
1306 		break;
1307 	default:
1308 		err = -ENOTTY;
1309 		break;
1310 	}
1311 
1312 	return err;
1313 }
1314 
1315 static const struct file_operations fastrpc_fops = {
1316 	.open = fastrpc_device_open,
1317 	.release = fastrpc_device_release,
1318 	.unlocked_ioctl = fastrpc_device_ioctl,
1319 	.compat_ioctl = fastrpc_device_ioctl,
1320 };
1321 
1322 static int fastrpc_cb_probe(struct platform_device *pdev)
1323 {
1324 	struct fastrpc_channel_ctx *cctx;
1325 	struct fastrpc_session_ctx *sess;
1326 	struct device *dev = &pdev->dev;
1327 	int i, sessions = 0;
1328 	unsigned long flags;
1329 	int rc;
1330 
1331 	cctx = dev_get_drvdata(dev->parent);
1332 	if (!cctx)
1333 		return -EINVAL;
1334 
1335 	of_property_read_u32(dev->of_node, "qcom,nsessions", &sessions);
1336 
1337 	spin_lock_irqsave(&cctx->lock, flags);
1338 	sess = &cctx->session[cctx->sesscount];
1339 	sess->used = false;
1340 	sess->valid = true;
1341 	sess->dev = dev;
1342 	dev_set_drvdata(dev, sess);
1343 
1344 	if (of_property_read_u32(dev->of_node, "reg", &sess->sid))
1345 		dev_info(dev, "FastRPC Session ID not specified in DT\n");
1346 
1347 	if (sessions > 0) {
1348 		struct fastrpc_session_ctx *dup_sess;
1349 
1350 		for (i = 1; i < sessions; i++) {
1351 			if (cctx->sesscount++ >= FASTRPC_MAX_SESSIONS)
1352 				break;
1353 			dup_sess = &cctx->session[cctx->sesscount];
1354 			memcpy(dup_sess, sess, sizeof(*dup_sess));
1355 		}
1356 	}
1357 	cctx->sesscount++;
1358 	spin_unlock_irqrestore(&cctx->lock, flags);
1359 	rc = dma_set_mask(dev, DMA_BIT_MASK(32));
1360 	if (rc) {
1361 		dev_err(dev, "32-bit DMA enable failed\n");
1362 		return rc;
1363 	}
1364 
1365 	return 0;
1366 }
1367 
1368 static int fastrpc_cb_remove(struct platform_device *pdev)
1369 {
1370 	struct fastrpc_channel_ctx *cctx = dev_get_drvdata(pdev->dev.parent);
1371 	struct fastrpc_session_ctx *sess = dev_get_drvdata(&pdev->dev);
1372 	unsigned long flags;
1373 	int i;
1374 
1375 	spin_lock_irqsave(&cctx->lock, flags);
1376 	for (i = 1; i < FASTRPC_MAX_SESSIONS; i++) {
1377 		if (cctx->session[i].sid == sess->sid) {
1378 			cctx->session[i].valid = false;
1379 			cctx->sesscount--;
1380 		}
1381 	}
1382 	spin_unlock_irqrestore(&cctx->lock, flags);
1383 
1384 	return 0;
1385 }
1386 
1387 static const struct of_device_id fastrpc_match_table[] = {
1388 	{ .compatible = "qcom,fastrpc-compute-cb", },
1389 	{}
1390 };
1391 
1392 static struct platform_driver fastrpc_cb_driver = {
1393 	.probe = fastrpc_cb_probe,
1394 	.remove = fastrpc_cb_remove,
1395 	.driver = {
1396 		.name = "qcom,fastrpc-cb",
1397 		.of_match_table = fastrpc_match_table,
1398 		.suppress_bind_attrs = true,
1399 	},
1400 };
1401 
1402 static int fastrpc_rpmsg_probe(struct rpmsg_device *rpdev)
1403 {
1404 	struct device *rdev = &rpdev->dev;
1405 	struct fastrpc_channel_ctx *data;
1406 	int i, err, domain_id = -1;
1407 	const char *domain;
1408 
1409 	err = of_property_read_string(rdev->of_node, "label", &domain);
1410 	if (err) {
1411 		dev_info(rdev, "FastRPC Domain not specified in DT\n");
1412 		return err;
1413 	}
1414 
1415 	for (i = 0; i <= CDSP_DOMAIN_ID; i++) {
1416 		if (!strcmp(domains[i], domain)) {
1417 			domain_id = i;
1418 			break;
1419 		}
1420 	}
1421 
1422 	if (domain_id < 0) {
1423 		dev_info(rdev, "FastRPC Invalid Domain ID %d\n", domain_id);
1424 		return -EINVAL;
1425 	}
1426 
1427 	data = kzalloc(sizeof(*data), GFP_KERNEL);
1428 	if (!data)
1429 		return -ENOMEM;
1430 
1431 	data->miscdev.minor = MISC_DYNAMIC_MINOR;
1432 	data->miscdev.name = kasprintf(GFP_KERNEL, "fastrpc-%s",
1433 				domains[domain_id]);
1434 	data->miscdev.fops = &fastrpc_fops;
1435 	err = misc_register(&data->miscdev);
1436 	if (err)
1437 		return err;
1438 
1439 	kref_init(&data->refcount);
1440 
1441 	dev_set_drvdata(&rpdev->dev, data);
1442 	dma_set_mask_and_coherent(rdev, DMA_BIT_MASK(32));
1443 	INIT_LIST_HEAD(&data->users);
1444 	spin_lock_init(&data->lock);
1445 	idr_init(&data->ctx_idr);
1446 	data->domain_id = domain_id;
1447 	data->rpdev = rpdev;
1448 
1449 	return of_platform_populate(rdev->of_node, NULL, NULL, rdev);
1450 }
1451 
1452 static void fastrpc_notify_users(struct fastrpc_user *user)
1453 {
1454 	struct fastrpc_invoke_ctx *ctx;
1455 
1456 	spin_lock(&user->lock);
1457 	list_for_each_entry(ctx, &user->pending, node)
1458 		complete(&ctx->work);
1459 	spin_unlock(&user->lock);
1460 }
1461 
1462 static void fastrpc_rpmsg_remove(struct rpmsg_device *rpdev)
1463 {
1464 	struct fastrpc_channel_ctx *cctx = dev_get_drvdata(&rpdev->dev);
1465 	struct fastrpc_user *user;
1466 	unsigned long flags;
1467 
1468 	spin_lock_irqsave(&cctx->lock, flags);
1469 	list_for_each_entry(user, &cctx->users, user)
1470 		fastrpc_notify_users(user);
1471 	spin_unlock_irqrestore(&cctx->lock, flags);
1472 
1473 	misc_deregister(&cctx->miscdev);
1474 	of_platform_depopulate(&rpdev->dev);
1475 
1476 	cctx->rpdev = NULL;
1477 	fastrpc_channel_ctx_put(cctx);
1478 }
1479 
1480 static int fastrpc_rpmsg_callback(struct rpmsg_device *rpdev, void *data,
1481 				  int len, void *priv, u32 addr)
1482 {
1483 	struct fastrpc_channel_ctx *cctx = dev_get_drvdata(&rpdev->dev);
1484 	struct fastrpc_invoke_rsp *rsp = data;
1485 	struct fastrpc_invoke_ctx *ctx;
1486 	unsigned long flags;
1487 	unsigned long ctxid;
1488 
1489 	if (len < sizeof(*rsp))
1490 		return -EINVAL;
1491 
1492 	ctxid = ((rsp->ctx & FASTRPC_CTXID_MASK) >> 4);
1493 
1494 	spin_lock_irqsave(&cctx->lock, flags);
1495 	ctx = idr_find(&cctx->ctx_idr, ctxid);
1496 	spin_unlock_irqrestore(&cctx->lock, flags);
1497 
1498 	if (!ctx) {
1499 		dev_err(&rpdev->dev, "No context ID matches response\n");
1500 		return -ENOENT;
1501 	}
1502 
1503 	ctx->retval = rsp->retval;
1504 	complete(&ctx->work);
1505 
1506 	/*
1507 	 * The DMA buffer associated with the context cannot be freed in
1508 	 * interrupt context so schedule it through a worker thread to
1509 	 * avoid a kernel BUG.
1510 	 */
1511 	schedule_work(&ctx->put_work);
1512 
1513 	return 0;
1514 }
1515 
1516 static const struct of_device_id fastrpc_rpmsg_of_match[] = {
1517 	{ .compatible = "qcom,fastrpc" },
1518 	{ },
1519 };
1520 MODULE_DEVICE_TABLE(of, fastrpc_rpmsg_of_match);
1521 
1522 static struct rpmsg_driver fastrpc_driver = {
1523 	.probe = fastrpc_rpmsg_probe,
1524 	.remove = fastrpc_rpmsg_remove,
1525 	.callback = fastrpc_rpmsg_callback,
1526 	.drv = {
1527 		.name = "qcom,fastrpc",
1528 		.of_match_table = fastrpc_rpmsg_of_match,
1529 	},
1530 };
1531 
1532 static int fastrpc_init(void)
1533 {
1534 	int ret;
1535 
1536 	ret = platform_driver_register(&fastrpc_cb_driver);
1537 	if (ret < 0) {
1538 		pr_err("fastrpc: failed to register cb driver\n");
1539 		return ret;
1540 	}
1541 
1542 	ret = register_rpmsg_driver(&fastrpc_driver);
1543 	if (ret < 0) {
1544 		pr_err("fastrpc: failed to register rpmsg driver\n");
1545 		platform_driver_unregister(&fastrpc_cb_driver);
1546 		return ret;
1547 	}
1548 
1549 	return 0;
1550 }
1551 module_init(fastrpc_init);
1552 
1553 static void fastrpc_exit(void)
1554 {
1555 	platform_driver_unregister(&fastrpc_cb_driver);
1556 	unregister_rpmsg_driver(&fastrpc_driver);
1557 }
1558 module_exit(fastrpc_exit);
1559 
1560 MODULE_LICENSE("GPL v2");
1561