xref: /linux/drivers/misc/fastrpc.c (revision 17cfcb68af3bc7d5e8ae08779b1853310a2949f3)
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 		kfree(a);
531 		return -EINVAL;
532 	}
533 
534 	a->dev = attachment->dev;
535 	INIT_LIST_HEAD(&a->node);
536 	attachment->priv = a;
537 
538 	mutex_lock(&buffer->lock);
539 	list_add(&a->node, &buffer->attachments);
540 	mutex_unlock(&buffer->lock);
541 
542 	return 0;
543 }
544 
545 static void fastrpc_dma_buf_detatch(struct dma_buf *dmabuf,
546 				    struct dma_buf_attachment *attachment)
547 {
548 	struct fastrpc_dma_buf_attachment *a = attachment->priv;
549 	struct fastrpc_buf *buffer = dmabuf->priv;
550 
551 	mutex_lock(&buffer->lock);
552 	list_del(&a->node);
553 	mutex_unlock(&buffer->lock);
554 	sg_free_table(&a->sgt);
555 	kfree(a);
556 }
557 
558 static void *fastrpc_vmap(struct dma_buf *dmabuf)
559 {
560 	struct fastrpc_buf *buf = dmabuf->priv;
561 
562 	return buf->virt;
563 }
564 
565 static int fastrpc_mmap(struct dma_buf *dmabuf,
566 			struct vm_area_struct *vma)
567 {
568 	struct fastrpc_buf *buf = dmabuf->priv;
569 	size_t size = vma->vm_end - vma->vm_start;
570 
571 	return dma_mmap_coherent(buf->dev, vma, buf->virt,
572 				 FASTRPC_PHYS(buf->phys), size);
573 }
574 
575 static const struct dma_buf_ops fastrpc_dma_buf_ops = {
576 	.attach = fastrpc_dma_buf_attach,
577 	.detach = fastrpc_dma_buf_detatch,
578 	.map_dma_buf = fastrpc_map_dma_buf,
579 	.unmap_dma_buf = fastrpc_unmap_dma_buf,
580 	.mmap = fastrpc_mmap,
581 	.vmap = fastrpc_vmap,
582 	.release = fastrpc_release,
583 };
584 
585 static int fastrpc_map_create(struct fastrpc_user *fl, int fd,
586 			      u64 len, struct fastrpc_map **ppmap)
587 {
588 	struct fastrpc_session_ctx *sess = fl->sctx;
589 	struct fastrpc_map *map = NULL;
590 	int err = 0;
591 
592 	if (!fastrpc_map_find(fl, fd, ppmap))
593 		return 0;
594 
595 	map = kzalloc(sizeof(*map), GFP_KERNEL);
596 	if (!map)
597 		return -ENOMEM;
598 
599 	INIT_LIST_HEAD(&map->node);
600 	map->fl = fl;
601 	map->fd = fd;
602 	map->buf = dma_buf_get(fd);
603 	if (IS_ERR(map->buf)) {
604 		err = PTR_ERR(map->buf);
605 		goto get_err;
606 	}
607 
608 	map->attach = dma_buf_attach(map->buf, sess->dev);
609 	if (IS_ERR(map->attach)) {
610 		dev_err(sess->dev, "Failed to attach dmabuf\n");
611 		err = PTR_ERR(map->attach);
612 		goto attach_err;
613 	}
614 
615 	map->table = dma_buf_map_attachment(map->attach, DMA_BIDIRECTIONAL);
616 	if (IS_ERR(map->table)) {
617 		err = PTR_ERR(map->table);
618 		goto map_err;
619 	}
620 
621 	map->phys = sg_dma_address(map->table->sgl);
622 	map->phys += ((u64)fl->sctx->sid << 32);
623 	map->size = len;
624 	map->va = sg_virt(map->table->sgl);
625 	map->len = len;
626 	kref_init(&map->refcount);
627 
628 	spin_lock(&fl->lock);
629 	list_add_tail(&map->node, &fl->maps);
630 	spin_unlock(&fl->lock);
631 	*ppmap = map;
632 
633 	return 0;
634 
635 map_err:
636 	dma_buf_detach(map->buf, map->attach);
637 attach_err:
638 	dma_buf_put(map->buf);
639 get_err:
640 	kfree(map);
641 
642 	return err;
643 }
644 
645 /*
646  * Fastrpc payload buffer with metadata looks like:
647  *
648  * >>>>>>  START of METADATA <<<<<<<<<
649  * +---------------------------------+
650  * |           Arguments             |
651  * | type:(struct fastrpc_remote_arg)|
652  * |             (0 - N)             |
653  * +---------------------------------+
654  * |         Invoke Buffer list      |
655  * | type:(struct fastrpc_invoke_buf)|
656  * |           (0 - N)               |
657  * +---------------------------------+
658  * |         Page info list          |
659  * | type:(struct fastrpc_phy_page)  |
660  * |             (0 - N)             |
661  * +---------------------------------+
662  * |         Optional info           |
663  * |(can be specific to SoC/Firmware)|
664  * +---------------------------------+
665  * >>>>>>>>  END of METADATA <<<<<<<<<
666  * +---------------------------------+
667  * |         Inline ARGS             |
668  * |            (0-N)                |
669  * +---------------------------------+
670  */
671 
672 static int fastrpc_get_meta_size(struct fastrpc_invoke_ctx *ctx)
673 {
674 	int size = 0;
675 
676 	size = (sizeof(struct fastrpc_remote_arg) +
677 		sizeof(struct fastrpc_invoke_buf) +
678 		sizeof(struct fastrpc_phy_page)) * ctx->nscalars +
679 		sizeof(u64) * FASTRPC_MAX_FDLIST +
680 		sizeof(u32) * FASTRPC_MAX_CRCLIST;
681 
682 	return size;
683 }
684 
685 static u64 fastrpc_get_payload_size(struct fastrpc_invoke_ctx *ctx, int metalen)
686 {
687 	u64 size = 0;
688 	int i;
689 
690 	size = ALIGN(metalen, FASTRPC_ALIGN);
691 	for (i = 0; i < ctx->nscalars; i++) {
692 		if (ctx->args[i].fd == 0 || ctx->args[i].fd == -1) {
693 
694 			if (ctx->olaps[i].offset == 0)
695 				size = ALIGN(size, FASTRPC_ALIGN);
696 
697 			size += (ctx->olaps[i].mend - ctx->olaps[i].mstart);
698 		}
699 	}
700 
701 	return size;
702 }
703 
704 static int fastrpc_create_maps(struct fastrpc_invoke_ctx *ctx)
705 {
706 	struct device *dev = ctx->fl->sctx->dev;
707 	int i, err;
708 
709 	for (i = 0; i < ctx->nscalars; ++i) {
710 		/* Make sure reserved field is set to 0 */
711 		if (ctx->args[i].reserved)
712 			return -EINVAL;
713 
714 		if (ctx->args[i].fd == 0 || ctx->args[i].fd == -1 ||
715 		    ctx->args[i].length == 0)
716 			continue;
717 
718 		err = fastrpc_map_create(ctx->fl, ctx->args[i].fd,
719 					 ctx->args[i].length, &ctx->maps[i]);
720 		if (err) {
721 			dev_err(dev, "Error Creating map %d\n", err);
722 			return -EINVAL;
723 		}
724 
725 	}
726 	return 0;
727 }
728 
729 static int fastrpc_get_args(u32 kernel, struct fastrpc_invoke_ctx *ctx)
730 {
731 	struct device *dev = ctx->fl->sctx->dev;
732 	struct fastrpc_remote_arg *rpra;
733 	struct fastrpc_invoke_buf *list;
734 	struct fastrpc_phy_page *pages;
735 	int inbufs, i, oix, err = 0;
736 	u64 len, rlen, pkt_size;
737 	u64 pg_start, pg_end;
738 	uintptr_t args;
739 	int metalen;
740 
741 	inbufs = REMOTE_SCALARS_INBUFS(ctx->sc);
742 	metalen = fastrpc_get_meta_size(ctx);
743 	pkt_size = fastrpc_get_payload_size(ctx, metalen);
744 
745 	err = fastrpc_create_maps(ctx);
746 	if (err)
747 		return err;
748 
749 	ctx->msg_sz = pkt_size;
750 
751 	err = fastrpc_buf_alloc(ctx->fl, dev, pkt_size, &ctx->buf);
752 	if (err)
753 		return err;
754 
755 	rpra = ctx->buf->virt;
756 	list = ctx->buf->virt + ctx->nscalars * sizeof(*rpra);
757 	pages = ctx->buf->virt + ctx->nscalars * (sizeof(*list) +
758 		sizeof(*rpra));
759 	args = (uintptr_t)ctx->buf->virt + metalen;
760 	rlen = pkt_size - metalen;
761 	ctx->rpra = rpra;
762 
763 	for (oix = 0; oix < ctx->nbufs; ++oix) {
764 		int mlen;
765 
766 		i = ctx->olaps[oix].raix;
767 		len = ctx->args[i].length;
768 
769 		rpra[i].pv = 0;
770 		rpra[i].len = len;
771 		list[i].num = len ? 1 : 0;
772 		list[i].pgidx = i;
773 
774 		if (!len)
775 			continue;
776 
777 		if (ctx->maps[i]) {
778 			struct vm_area_struct *vma = NULL;
779 
780 			rpra[i].pv = (u64) ctx->args[i].ptr;
781 			pages[i].addr = ctx->maps[i]->phys;
782 
783 			vma = find_vma(current->mm, ctx->args[i].ptr);
784 			if (vma)
785 				pages[i].addr += ctx->args[i].ptr -
786 						 vma->vm_start;
787 
788 			pg_start = (ctx->args[i].ptr & PAGE_MASK) >> PAGE_SHIFT;
789 			pg_end = ((ctx->args[i].ptr + len - 1) & PAGE_MASK) >>
790 				  PAGE_SHIFT;
791 			pages[i].size = (pg_end - pg_start + 1) * PAGE_SIZE;
792 
793 		} else {
794 
795 			if (ctx->olaps[oix].offset == 0) {
796 				rlen -= ALIGN(args, FASTRPC_ALIGN) - args;
797 				args = ALIGN(args, FASTRPC_ALIGN);
798 			}
799 
800 			mlen = ctx->olaps[oix].mend - ctx->olaps[oix].mstart;
801 
802 			if (rlen < mlen)
803 				goto bail;
804 
805 			rpra[i].pv = args - ctx->olaps[oix].offset;
806 			pages[i].addr = ctx->buf->phys -
807 					ctx->olaps[oix].offset +
808 					(pkt_size - rlen);
809 			pages[i].addr = pages[i].addr &	PAGE_MASK;
810 
811 			pg_start = (args & PAGE_MASK) >> PAGE_SHIFT;
812 			pg_end = ((args + len - 1) & PAGE_MASK) >> PAGE_SHIFT;
813 			pages[i].size = (pg_end - pg_start + 1) * PAGE_SIZE;
814 			args = args + mlen;
815 			rlen -= mlen;
816 		}
817 
818 		if (i < inbufs && !ctx->maps[i]) {
819 			void *dst = (void *)(uintptr_t)rpra[i].pv;
820 			void *src = (void *)(uintptr_t)ctx->args[i].ptr;
821 
822 			if (!kernel) {
823 				if (copy_from_user(dst, (void __user *)src,
824 						   len)) {
825 					err = -EFAULT;
826 					goto bail;
827 				}
828 			} else {
829 				memcpy(dst, src, len);
830 			}
831 		}
832 	}
833 
834 	for (i = ctx->nbufs; i < ctx->nscalars; ++i) {
835 		rpra[i].pv = (u64) ctx->args[i].ptr;
836 		rpra[i].len = ctx->args[i].length;
837 		list[i].num = ctx->args[i].length ? 1 : 0;
838 		list[i].pgidx = i;
839 		pages[i].addr = ctx->maps[i]->phys;
840 		pages[i].size = ctx->maps[i]->size;
841 	}
842 
843 bail:
844 	if (err)
845 		dev_err(dev, "Error: get invoke args failed:%d\n", err);
846 
847 	return err;
848 }
849 
850 static int fastrpc_put_args(struct fastrpc_invoke_ctx *ctx,
851 			    u32 kernel)
852 {
853 	struct fastrpc_remote_arg *rpra = ctx->rpra;
854 	int i, inbufs;
855 
856 	inbufs = REMOTE_SCALARS_INBUFS(ctx->sc);
857 
858 	for (i = inbufs; i < ctx->nbufs; ++i) {
859 		void *src = (void *)(uintptr_t)rpra[i].pv;
860 		void *dst = (void *)(uintptr_t)ctx->args[i].ptr;
861 		u64 len = rpra[i].len;
862 
863 		if (!kernel) {
864 			if (copy_to_user((void __user *)dst, src, len))
865 				return -EFAULT;
866 		} else {
867 			memcpy(dst, src, len);
868 		}
869 	}
870 
871 	return 0;
872 }
873 
874 static int fastrpc_invoke_send(struct fastrpc_session_ctx *sctx,
875 			       struct fastrpc_invoke_ctx *ctx,
876 			       u32 kernel, uint32_t handle)
877 {
878 	struct fastrpc_channel_ctx *cctx;
879 	struct fastrpc_user *fl = ctx->fl;
880 	struct fastrpc_msg *msg = &ctx->msg;
881 
882 	cctx = fl->cctx;
883 	msg->pid = fl->tgid;
884 	msg->tid = current->pid;
885 
886 	if (kernel)
887 		msg->pid = 0;
888 
889 	msg->ctx = ctx->ctxid | fl->pd;
890 	msg->handle = handle;
891 	msg->sc = ctx->sc;
892 	msg->addr = ctx->buf ? ctx->buf->phys : 0;
893 	msg->size = roundup(ctx->msg_sz, PAGE_SIZE);
894 	fastrpc_context_get(ctx);
895 
896 	return rpmsg_send(cctx->rpdev->ept, (void *)msg, sizeof(*msg));
897 }
898 
899 static int fastrpc_internal_invoke(struct fastrpc_user *fl,  u32 kernel,
900 				   u32 handle, u32 sc,
901 				   struct fastrpc_invoke_args *args)
902 {
903 	struct fastrpc_invoke_ctx *ctx = NULL;
904 	int err = 0;
905 
906 	if (!fl->sctx)
907 		return -EINVAL;
908 
909 	if (!fl->cctx->rpdev)
910 		return -EPIPE;
911 
912 	ctx = fastrpc_context_alloc(fl, kernel, sc, args);
913 	if (IS_ERR(ctx))
914 		return PTR_ERR(ctx);
915 
916 	if (ctx->nscalars) {
917 		err = fastrpc_get_args(kernel, ctx);
918 		if (err)
919 			goto bail;
920 	}
921 
922 	/* make sure that all CPU memory writes are seen by DSP */
923 	dma_wmb();
924 	/* Send invoke buffer to remote dsp */
925 	err = fastrpc_invoke_send(fl->sctx, ctx, kernel, handle);
926 	if (err)
927 		goto bail;
928 
929 	/* Wait for remote dsp to respond or time out */
930 	err = wait_for_completion_interruptible(&ctx->work);
931 	if (err)
932 		goto bail;
933 
934 	/* Check the response from remote dsp */
935 	err = ctx->retval;
936 	if (err)
937 		goto bail;
938 
939 	if (ctx->nscalars) {
940 		/* make sure that all memory writes by DSP are seen by CPU */
941 		dma_rmb();
942 		/* populate all the output buffers with results */
943 		err = fastrpc_put_args(ctx, kernel);
944 		if (err)
945 			goto bail;
946 	}
947 
948 bail:
949 	/* We are done with this compute context, remove it from pending list */
950 	spin_lock(&fl->lock);
951 	list_del(&ctx->node);
952 	spin_unlock(&fl->lock);
953 	fastrpc_context_put(ctx);
954 
955 	if (err)
956 		dev_dbg(fl->sctx->dev, "Error: Invoke Failed %d\n", err);
957 
958 	return err;
959 }
960 
961 static int fastrpc_init_create_process(struct fastrpc_user *fl,
962 					char __user *argp)
963 {
964 	struct fastrpc_init_create init;
965 	struct fastrpc_invoke_args *args;
966 	struct fastrpc_phy_page pages[1];
967 	struct fastrpc_map *map = NULL;
968 	struct fastrpc_buf *imem = NULL;
969 	int memlen;
970 	int err;
971 	struct {
972 		int pgid;
973 		u32 namelen;
974 		u32 filelen;
975 		u32 pageslen;
976 		u32 attrs;
977 		u32 siglen;
978 	} inbuf;
979 	u32 sc;
980 
981 	args = kcalloc(FASTRPC_CREATE_PROCESS_NARGS, sizeof(*args), GFP_KERNEL);
982 	if (!args)
983 		return -ENOMEM;
984 
985 	if (copy_from_user(&init, argp, sizeof(init))) {
986 		err = -EFAULT;
987 		goto err;
988 	}
989 
990 	if (init.filelen > INIT_FILELEN_MAX) {
991 		err = -EINVAL;
992 		goto err;
993 	}
994 
995 	inbuf.pgid = fl->tgid;
996 	inbuf.namelen = strlen(current->comm) + 1;
997 	inbuf.filelen = init.filelen;
998 	inbuf.pageslen = 1;
999 	inbuf.attrs = init.attrs;
1000 	inbuf.siglen = init.siglen;
1001 	fl->pd = 1;
1002 
1003 	if (init.filelen && init.filefd) {
1004 		err = fastrpc_map_create(fl, init.filefd, init.filelen, &map);
1005 		if (err)
1006 			goto err;
1007 	}
1008 
1009 	memlen = ALIGN(max(INIT_FILELEN_MAX, (int)init.filelen * 4),
1010 		       1024 * 1024);
1011 	err = fastrpc_buf_alloc(fl, fl->sctx->dev, memlen,
1012 				&imem);
1013 	if (err)
1014 		goto err_alloc;
1015 
1016 	fl->init_mem = imem;
1017 	args[0].ptr = (u64)(uintptr_t)&inbuf;
1018 	args[0].length = sizeof(inbuf);
1019 	args[0].fd = -1;
1020 
1021 	args[1].ptr = (u64)(uintptr_t)current->comm;
1022 	args[1].length = inbuf.namelen;
1023 	args[1].fd = -1;
1024 
1025 	args[2].ptr = (u64) init.file;
1026 	args[2].length = inbuf.filelen;
1027 	args[2].fd = init.filefd;
1028 
1029 	pages[0].addr = imem->phys;
1030 	pages[0].size = imem->size;
1031 
1032 	args[3].ptr = (u64)(uintptr_t) pages;
1033 	args[3].length = 1 * sizeof(*pages);
1034 	args[3].fd = -1;
1035 
1036 	args[4].ptr = (u64)(uintptr_t)&inbuf.attrs;
1037 	args[4].length = sizeof(inbuf.attrs);
1038 	args[4].fd = -1;
1039 
1040 	args[5].ptr = (u64)(uintptr_t) &inbuf.siglen;
1041 	args[5].length = sizeof(inbuf.siglen);
1042 	args[5].fd = -1;
1043 
1044 	sc = FASTRPC_SCALARS(FASTRPC_RMID_INIT_CREATE, 4, 0);
1045 	if (init.attrs)
1046 		sc = FASTRPC_SCALARS(FASTRPC_RMID_INIT_CREATE_ATTR, 6, 0);
1047 
1048 	err = fastrpc_internal_invoke(fl, true, FASTRPC_INIT_HANDLE,
1049 				      sc, args);
1050 	if (err)
1051 		goto err_invoke;
1052 
1053 	kfree(args);
1054 
1055 	return 0;
1056 
1057 err_invoke:
1058 	fl->init_mem = NULL;
1059 	fastrpc_buf_free(imem);
1060 err_alloc:
1061 	if (map) {
1062 		spin_lock(&fl->lock);
1063 		list_del(&map->node);
1064 		spin_unlock(&fl->lock);
1065 		fastrpc_map_put(map);
1066 	}
1067 err:
1068 	kfree(args);
1069 
1070 	return err;
1071 }
1072 
1073 static struct fastrpc_session_ctx *fastrpc_session_alloc(
1074 					struct fastrpc_channel_ctx *cctx)
1075 {
1076 	struct fastrpc_session_ctx *session = NULL;
1077 	unsigned long flags;
1078 	int i;
1079 
1080 	spin_lock_irqsave(&cctx->lock, flags);
1081 	for (i = 0; i < cctx->sesscount; i++) {
1082 		if (!cctx->session[i].used && cctx->session[i].valid) {
1083 			cctx->session[i].used = true;
1084 			session = &cctx->session[i];
1085 			break;
1086 		}
1087 	}
1088 	spin_unlock_irqrestore(&cctx->lock, flags);
1089 
1090 	return session;
1091 }
1092 
1093 static void fastrpc_session_free(struct fastrpc_channel_ctx *cctx,
1094 				 struct fastrpc_session_ctx *session)
1095 {
1096 	unsigned long flags;
1097 
1098 	spin_lock_irqsave(&cctx->lock, flags);
1099 	session->used = false;
1100 	spin_unlock_irqrestore(&cctx->lock, flags);
1101 }
1102 
1103 static int fastrpc_release_current_dsp_process(struct fastrpc_user *fl)
1104 {
1105 	struct fastrpc_invoke_args args[1];
1106 	int tgid = 0;
1107 	u32 sc;
1108 
1109 	tgid = fl->tgid;
1110 	args[0].ptr = (u64)(uintptr_t) &tgid;
1111 	args[0].length = sizeof(tgid);
1112 	args[0].fd = -1;
1113 	args[0].reserved = 0;
1114 	sc = FASTRPC_SCALARS(FASTRPC_RMID_INIT_RELEASE, 1, 0);
1115 
1116 	return fastrpc_internal_invoke(fl, true, FASTRPC_INIT_HANDLE,
1117 				       sc, &args[0]);
1118 }
1119 
1120 static int fastrpc_device_release(struct inode *inode, struct file *file)
1121 {
1122 	struct fastrpc_user *fl = (struct fastrpc_user *)file->private_data;
1123 	struct fastrpc_channel_ctx *cctx = fl->cctx;
1124 	struct fastrpc_invoke_ctx *ctx, *n;
1125 	struct fastrpc_map *map, *m;
1126 	unsigned long flags;
1127 
1128 	fastrpc_release_current_dsp_process(fl);
1129 
1130 	spin_lock_irqsave(&cctx->lock, flags);
1131 	list_del(&fl->user);
1132 	spin_unlock_irqrestore(&cctx->lock, flags);
1133 
1134 	if (fl->init_mem)
1135 		fastrpc_buf_free(fl->init_mem);
1136 
1137 	list_for_each_entry_safe(ctx, n, &fl->pending, node) {
1138 		list_del(&ctx->node);
1139 		fastrpc_context_put(ctx);
1140 	}
1141 
1142 	list_for_each_entry_safe(map, m, &fl->maps, node) {
1143 		list_del(&map->node);
1144 		fastrpc_map_put(map);
1145 	}
1146 
1147 	fastrpc_session_free(cctx, fl->sctx);
1148 	fastrpc_channel_ctx_put(cctx);
1149 
1150 	mutex_destroy(&fl->mutex);
1151 	kfree(fl);
1152 	file->private_data = NULL;
1153 
1154 	return 0;
1155 }
1156 
1157 static int fastrpc_device_open(struct inode *inode, struct file *filp)
1158 {
1159 	struct fastrpc_channel_ctx *cctx = miscdev_to_cctx(filp->private_data);
1160 	struct fastrpc_user *fl = NULL;
1161 	unsigned long flags;
1162 
1163 	fl = kzalloc(sizeof(*fl), GFP_KERNEL);
1164 	if (!fl)
1165 		return -ENOMEM;
1166 
1167 	/* Released in fastrpc_device_release() */
1168 	fastrpc_channel_ctx_get(cctx);
1169 
1170 	filp->private_data = fl;
1171 	spin_lock_init(&fl->lock);
1172 	mutex_init(&fl->mutex);
1173 	INIT_LIST_HEAD(&fl->pending);
1174 	INIT_LIST_HEAD(&fl->maps);
1175 	INIT_LIST_HEAD(&fl->user);
1176 	fl->tgid = current->tgid;
1177 	fl->cctx = cctx;
1178 
1179 	fl->sctx = fastrpc_session_alloc(cctx);
1180 	if (!fl->sctx) {
1181 		dev_err(&cctx->rpdev->dev, "No session available\n");
1182 		mutex_destroy(&fl->mutex);
1183 		kfree(fl);
1184 
1185 		return -EBUSY;
1186 	}
1187 
1188 	spin_lock_irqsave(&cctx->lock, flags);
1189 	list_add_tail(&fl->user, &cctx->users);
1190 	spin_unlock_irqrestore(&cctx->lock, flags);
1191 
1192 	return 0;
1193 }
1194 
1195 static int fastrpc_dmabuf_alloc(struct fastrpc_user *fl, char __user *argp)
1196 {
1197 	struct fastrpc_alloc_dma_buf bp;
1198 	DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
1199 	struct fastrpc_buf *buf = NULL;
1200 	int err;
1201 
1202 	if (copy_from_user(&bp, argp, sizeof(bp)))
1203 		return -EFAULT;
1204 
1205 	err = fastrpc_buf_alloc(fl, fl->sctx->dev, bp.size, &buf);
1206 	if (err)
1207 		return err;
1208 	exp_info.ops = &fastrpc_dma_buf_ops;
1209 	exp_info.size = bp.size;
1210 	exp_info.flags = O_RDWR;
1211 	exp_info.priv = buf;
1212 	buf->dmabuf = dma_buf_export(&exp_info);
1213 	if (IS_ERR(buf->dmabuf)) {
1214 		err = PTR_ERR(buf->dmabuf);
1215 		fastrpc_buf_free(buf);
1216 		return err;
1217 	}
1218 
1219 	bp.fd = dma_buf_fd(buf->dmabuf, O_ACCMODE);
1220 	if (bp.fd < 0) {
1221 		dma_buf_put(buf->dmabuf);
1222 		return -EINVAL;
1223 	}
1224 
1225 	if (copy_to_user(argp, &bp, sizeof(bp))) {
1226 		dma_buf_put(buf->dmabuf);
1227 		return -EFAULT;
1228 	}
1229 
1230 	return 0;
1231 }
1232 
1233 static int fastrpc_init_attach(struct fastrpc_user *fl)
1234 {
1235 	struct fastrpc_invoke_args args[1];
1236 	int tgid = fl->tgid;
1237 	u32 sc;
1238 
1239 	args[0].ptr = (u64)(uintptr_t) &tgid;
1240 	args[0].length = sizeof(tgid);
1241 	args[0].fd = -1;
1242 	args[0].reserved = 0;
1243 	sc = FASTRPC_SCALARS(FASTRPC_RMID_INIT_ATTACH, 1, 0);
1244 	fl->pd = 0;
1245 
1246 	return fastrpc_internal_invoke(fl, true, FASTRPC_INIT_HANDLE,
1247 				       sc, &args[0]);
1248 }
1249 
1250 static int fastrpc_invoke(struct fastrpc_user *fl, char __user *argp)
1251 {
1252 	struct fastrpc_invoke_args *args = NULL;
1253 	struct fastrpc_invoke inv;
1254 	u32 nscalars;
1255 	int err;
1256 
1257 	if (copy_from_user(&inv, argp, sizeof(inv)))
1258 		return -EFAULT;
1259 
1260 	/* nscalars is truncated here to max supported value */
1261 	nscalars = REMOTE_SCALARS_LENGTH(inv.sc);
1262 	if (nscalars) {
1263 		args = kcalloc(nscalars, sizeof(*args), GFP_KERNEL);
1264 		if (!args)
1265 			return -ENOMEM;
1266 
1267 		if (copy_from_user(args, (void __user *)(uintptr_t)inv.args,
1268 				   nscalars * sizeof(*args))) {
1269 			kfree(args);
1270 			return -EFAULT;
1271 		}
1272 	}
1273 
1274 	err = fastrpc_internal_invoke(fl, false, inv.handle, inv.sc, args);
1275 	kfree(args);
1276 
1277 	return err;
1278 }
1279 
1280 static long fastrpc_device_ioctl(struct file *file, unsigned int cmd,
1281 				 unsigned long arg)
1282 {
1283 	struct fastrpc_user *fl = (struct fastrpc_user *)file->private_data;
1284 	char __user *argp = (char __user *)arg;
1285 	int err;
1286 
1287 	switch (cmd) {
1288 	case FASTRPC_IOCTL_INVOKE:
1289 		err = fastrpc_invoke(fl, argp);
1290 		break;
1291 	case FASTRPC_IOCTL_INIT_ATTACH:
1292 		err = fastrpc_init_attach(fl);
1293 		break;
1294 	case FASTRPC_IOCTL_INIT_CREATE:
1295 		err = fastrpc_init_create_process(fl, argp);
1296 		break;
1297 	case FASTRPC_IOCTL_ALLOC_DMA_BUFF:
1298 		err = fastrpc_dmabuf_alloc(fl, argp);
1299 		break;
1300 	default:
1301 		err = -ENOTTY;
1302 		break;
1303 	}
1304 
1305 	return err;
1306 }
1307 
1308 static const struct file_operations fastrpc_fops = {
1309 	.open = fastrpc_device_open,
1310 	.release = fastrpc_device_release,
1311 	.unlocked_ioctl = fastrpc_device_ioctl,
1312 	.compat_ioctl = fastrpc_device_ioctl,
1313 };
1314 
1315 static int fastrpc_cb_probe(struct platform_device *pdev)
1316 {
1317 	struct fastrpc_channel_ctx *cctx;
1318 	struct fastrpc_session_ctx *sess;
1319 	struct device *dev = &pdev->dev;
1320 	int i, sessions = 0;
1321 	unsigned long flags;
1322 	int rc;
1323 
1324 	cctx = dev_get_drvdata(dev->parent);
1325 	if (!cctx)
1326 		return -EINVAL;
1327 
1328 	of_property_read_u32(dev->of_node, "qcom,nsessions", &sessions);
1329 
1330 	spin_lock_irqsave(&cctx->lock, flags);
1331 	sess = &cctx->session[cctx->sesscount];
1332 	sess->used = false;
1333 	sess->valid = true;
1334 	sess->dev = dev;
1335 	dev_set_drvdata(dev, sess);
1336 
1337 	if (of_property_read_u32(dev->of_node, "reg", &sess->sid))
1338 		dev_info(dev, "FastRPC Session ID not specified in DT\n");
1339 
1340 	if (sessions > 0) {
1341 		struct fastrpc_session_ctx *dup_sess;
1342 
1343 		for (i = 1; i < sessions; i++) {
1344 			if (cctx->sesscount++ >= FASTRPC_MAX_SESSIONS)
1345 				break;
1346 			dup_sess = &cctx->session[cctx->sesscount];
1347 			memcpy(dup_sess, sess, sizeof(*dup_sess));
1348 		}
1349 	}
1350 	cctx->sesscount++;
1351 	spin_unlock_irqrestore(&cctx->lock, flags);
1352 	rc = dma_set_mask(dev, DMA_BIT_MASK(32));
1353 	if (rc) {
1354 		dev_err(dev, "32-bit DMA enable failed\n");
1355 		return rc;
1356 	}
1357 
1358 	return 0;
1359 }
1360 
1361 static int fastrpc_cb_remove(struct platform_device *pdev)
1362 {
1363 	struct fastrpc_channel_ctx *cctx = dev_get_drvdata(pdev->dev.parent);
1364 	struct fastrpc_session_ctx *sess = dev_get_drvdata(&pdev->dev);
1365 	unsigned long flags;
1366 	int i;
1367 
1368 	spin_lock_irqsave(&cctx->lock, flags);
1369 	for (i = 1; i < FASTRPC_MAX_SESSIONS; i++) {
1370 		if (cctx->session[i].sid == sess->sid) {
1371 			cctx->session[i].valid = false;
1372 			cctx->sesscount--;
1373 		}
1374 	}
1375 	spin_unlock_irqrestore(&cctx->lock, flags);
1376 
1377 	return 0;
1378 }
1379 
1380 static const struct of_device_id fastrpc_match_table[] = {
1381 	{ .compatible = "qcom,fastrpc-compute-cb", },
1382 	{}
1383 };
1384 
1385 static struct platform_driver fastrpc_cb_driver = {
1386 	.probe = fastrpc_cb_probe,
1387 	.remove = fastrpc_cb_remove,
1388 	.driver = {
1389 		.name = "qcom,fastrpc-cb",
1390 		.of_match_table = fastrpc_match_table,
1391 		.suppress_bind_attrs = true,
1392 	},
1393 };
1394 
1395 static int fastrpc_rpmsg_probe(struct rpmsg_device *rpdev)
1396 {
1397 	struct device *rdev = &rpdev->dev;
1398 	struct fastrpc_channel_ctx *data;
1399 	int i, err, domain_id = -1;
1400 	const char *domain;
1401 
1402 	err = of_property_read_string(rdev->of_node, "label", &domain);
1403 	if (err) {
1404 		dev_info(rdev, "FastRPC Domain not specified in DT\n");
1405 		return err;
1406 	}
1407 
1408 	for (i = 0; i <= CDSP_DOMAIN_ID; i++) {
1409 		if (!strcmp(domains[i], domain)) {
1410 			domain_id = i;
1411 			break;
1412 		}
1413 	}
1414 
1415 	if (domain_id < 0) {
1416 		dev_info(rdev, "FastRPC Invalid Domain ID %d\n", domain_id);
1417 		return -EINVAL;
1418 	}
1419 
1420 	data = kzalloc(sizeof(*data), GFP_KERNEL);
1421 	if (!data)
1422 		return -ENOMEM;
1423 
1424 	data->miscdev.minor = MISC_DYNAMIC_MINOR;
1425 	data->miscdev.name = kasprintf(GFP_KERNEL, "fastrpc-%s",
1426 				domains[domain_id]);
1427 	data->miscdev.fops = &fastrpc_fops;
1428 	err = misc_register(&data->miscdev);
1429 	if (err)
1430 		return err;
1431 
1432 	kref_init(&data->refcount);
1433 
1434 	dev_set_drvdata(&rpdev->dev, data);
1435 	dma_set_mask_and_coherent(rdev, DMA_BIT_MASK(32));
1436 	INIT_LIST_HEAD(&data->users);
1437 	spin_lock_init(&data->lock);
1438 	idr_init(&data->ctx_idr);
1439 	data->domain_id = domain_id;
1440 	data->rpdev = rpdev;
1441 
1442 	return of_platform_populate(rdev->of_node, NULL, NULL, rdev);
1443 }
1444 
1445 static void fastrpc_notify_users(struct fastrpc_user *user)
1446 {
1447 	struct fastrpc_invoke_ctx *ctx;
1448 
1449 	spin_lock(&user->lock);
1450 	list_for_each_entry(ctx, &user->pending, node)
1451 		complete(&ctx->work);
1452 	spin_unlock(&user->lock);
1453 }
1454 
1455 static void fastrpc_rpmsg_remove(struct rpmsg_device *rpdev)
1456 {
1457 	struct fastrpc_channel_ctx *cctx = dev_get_drvdata(&rpdev->dev);
1458 	struct fastrpc_user *user;
1459 	unsigned long flags;
1460 
1461 	spin_lock_irqsave(&cctx->lock, flags);
1462 	list_for_each_entry(user, &cctx->users, user)
1463 		fastrpc_notify_users(user);
1464 	spin_unlock_irqrestore(&cctx->lock, flags);
1465 
1466 	misc_deregister(&cctx->miscdev);
1467 	of_platform_depopulate(&rpdev->dev);
1468 
1469 	cctx->rpdev = NULL;
1470 	fastrpc_channel_ctx_put(cctx);
1471 }
1472 
1473 static int fastrpc_rpmsg_callback(struct rpmsg_device *rpdev, void *data,
1474 				  int len, void *priv, u32 addr)
1475 {
1476 	struct fastrpc_channel_ctx *cctx = dev_get_drvdata(&rpdev->dev);
1477 	struct fastrpc_invoke_rsp *rsp = data;
1478 	struct fastrpc_invoke_ctx *ctx;
1479 	unsigned long flags;
1480 	unsigned long ctxid;
1481 
1482 	if (len < sizeof(*rsp))
1483 		return -EINVAL;
1484 
1485 	ctxid = ((rsp->ctx & FASTRPC_CTXID_MASK) >> 4);
1486 
1487 	spin_lock_irqsave(&cctx->lock, flags);
1488 	ctx = idr_find(&cctx->ctx_idr, ctxid);
1489 	spin_unlock_irqrestore(&cctx->lock, flags);
1490 
1491 	if (!ctx) {
1492 		dev_err(&rpdev->dev, "No context ID matches response\n");
1493 		return -ENOENT;
1494 	}
1495 
1496 	ctx->retval = rsp->retval;
1497 	complete(&ctx->work);
1498 
1499 	/*
1500 	 * The DMA buffer associated with the context cannot be freed in
1501 	 * interrupt context so schedule it through a worker thread to
1502 	 * avoid a kernel BUG.
1503 	 */
1504 	schedule_work(&ctx->put_work);
1505 
1506 	return 0;
1507 }
1508 
1509 static const struct of_device_id fastrpc_rpmsg_of_match[] = {
1510 	{ .compatible = "qcom,fastrpc" },
1511 	{ },
1512 };
1513 MODULE_DEVICE_TABLE(of, fastrpc_rpmsg_of_match);
1514 
1515 static struct rpmsg_driver fastrpc_driver = {
1516 	.probe = fastrpc_rpmsg_probe,
1517 	.remove = fastrpc_rpmsg_remove,
1518 	.callback = fastrpc_rpmsg_callback,
1519 	.drv = {
1520 		.name = "qcom,fastrpc",
1521 		.of_match_table = fastrpc_rpmsg_of_match,
1522 	},
1523 };
1524 
1525 static int fastrpc_init(void)
1526 {
1527 	int ret;
1528 
1529 	ret = platform_driver_register(&fastrpc_cb_driver);
1530 	if (ret < 0) {
1531 		pr_err("fastrpc: failed to register cb driver\n");
1532 		return ret;
1533 	}
1534 
1535 	ret = register_rpmsg_driver(&fastrpc_driver);
1536 	if (ret < 0) {
1537 		pr_err("fastrpc: failed to register rpmsg driver\n");
1538 		platform_driver_unregister(&fastrpc_cb_driver);
1539 		return ret;
1540 	}
1541 
1542 	return 0;
1543 }
1544 module_init(fastrpc_init);
1545 
1546 static void fastrpc_exit(void)
1547 {
1548 	platform_driver_unregister(&fastrpc_cb_driver);
1549 	unregister_rpmsg_driver(&fastrpc_driver);
1550 }
1551 module_exit(fastrpc_exit);
1552 
1553 MODULE_LICENSE("GPL v2");
1554