xref: /openbmc/linux/drivers/misc/fastrpc.c (revision f519f0be)
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 INIT_MEMLEN_MAX  (8 * 1024 * 1024)
37 #define FASTRPC_DEVICE_NAME	"fastrpc"
38 
39 /* Retrives number of input buffers from the scalars parameter */
40 #define REMOTE_SCALARS_INBUFS(sc)	(((sc) >> 16) & 0x0ff)
41 
42 /* Retrives number of output buffers from the scalars parameter */
43 #define REMOTE_SCALARS_OUTBUFS(sc)	(((sc) >> 8) & 0x0ff)
44 
45 /* Retrives number of input handles from the scalars parameter */
46 #define REMOTE_SCALARS_INHANDLES(sc)	(((sc) >> 4) & 0x0f)
47 
48 /* Retrives number of output handles from the scalars parameter */
49 #define REMOTE_SCALARS_OUTHANDLES(sc)	((sc) & 0x0f)
50 
51 #define REMOTE_SCALARS_LENGTH(sc)	(REMOTE_SCALARS_INBUFS(sc) +   \
52 					 REMOTE_SCALARS_OUTBUFS(sc) +  \
53 					 REMOTE_SCALARS_INHANDLES(sc)+ \
54 					 REMOTE_SCALARS_OUTHANDLES(sc))
55 #define FASTRPC_BUILD_SCALARS(attr, method, in, out, oin, oout)  \
56 				(((attr & 0x07) << 29) |		\
57 				((method & 0x1f) << 24) |	\
58 				((in & 0xff) << 16) |		\
59 				((out & 0xff) <<  8) |		\
60 				((oin & 0x0f) <<  4) |		\
61 				(oout & 0x0f))
62 
63 #define FASTRPC_SCALARS(method, in, out) \
64 		FASTRPC_BUILD_SCALARS(0, method, in, out, 0, 0)
65 
66 #define FASTRPC_CREATE_PROCESS_NARGS	6
67 /* Remote Method id table */
68 #define FASTRPC_RMID_INIT_ATTACH	0
69 #define FASTRPC_RMID_INIT_RELEASE	1
70 #define FASTRPC_RMID_INIT_CREATE	6
71 #define FASTRPC_RMID_INIT_CREATE_ATTR	7
72 #define FASTRPC_RMID_INIT_CREATE_STATIC	8
73 
74 #define miscdev_to_cctx(d) container_of(d, struct fastrpc_channel_ctx, miscdev)
75 
76 static const char *domains[FASTRPC_DEV_MAX] = { "adsp", "mdsp",
77 						"sdsp", "cdsp"};
78 struct fastrpc_phy_page {
79 	u64 addr;		/* physical address */
80 	u64 size;		/* size of contiguous region */
81 };
82 
83 struct fastrpc_invoke_buf {
84 	u32 num;		/* number of contiguous regions */
85 	u32 pgidx;		/* index to start of contiguous region */
86 };
87 
88 struct fastrpc_remote_arg {
89 	u64 pv;
90 	u64 len;
91 };
92 
93 struct fastrpc_msg {
94 	int pid;		/* process group id */
95 	int tid;		/* thread id */
96 	u64 ctx;		/* invoke caller context */
97 	u32 handle;	/* handle to invoke */
98 	u32 sc;		/* scalars structure describing the data */
99 	u64 addr;		/* physical address */
100 	u64 size;		/* size of contiguous region */
101 };
102 
103 struct fastrpc_invoke_rsp {
104 	u64 ctx;		/* invoke caller context */
105 	int retval;		/* invoke return value */
106 };
107 
108 struct fastrpc_buf_overlap {
109 	u64 start;
110 	u64 end;
111 	int raix;
112 	u64 mstart;
113 	u64 mend;
114 	u64 offset;
115 };
116 
117 struct fastrpc_buf {
118 	struct fastrpc_user *fl;
119 	struct dma_buf *dmabuf;
120 	struct device *dev;
121 	void *virt;
122 	u64 phys;
123 	u64 size;
124 	/* Lock for dma buf attachments */
125 	struct mutex lock;
126 	struct list_head attachments;
127 };
128 
129 struct fastrpc_dma_buf_attachment {
130 	struct device *dev;
131 	struct sg_table sgt;
132 	struct list_head node;
133 };
134 
135 struct fastrpc_map {
136 	struct list_head node;
137 	struct fastrpc_user *fl;
138 	int fd;
139 	struct dma_buf *buf;
140 	struct sg_table *table;
141 	struct dma_buf_attachment *attach;
142 	u64 phys;
143 	u64 size;
144 	void *va;
145 	u64 len;
146 	struct kref refcount;
147 };
148 
149 struct fastrpc_invoke_ctx {
150 	int nscalars;
151 	int nbufs;
152 	int retval;
153 	int pid;
154 	int tgid;
155 	u32 sc;
156 	u32 *crc;
157 	u64 ctxid;
158 	u64 msg_sz;
159 	struct kref refcount;
160 	struct list_head node; /* list of ctxs */
161 	struct completion work;
162 	struct work_struct put_work;
163 	struct fastrpc_msg msg;
164 	struct fastrpc_user *fl;
165 	struct fastrpc_remote_arg *rpra;
166 	struct fastrpc_map **maps;
167 	struct fastrpc_buf *buf;
168 	struct fastrpc_invoke_args *args;
169 	struct fastrpc_buf_overlap *olaps;
170 	struct fastrpc_channel_ctx *cctx;
171 };
172 
173 struct fastrpc_session_ctx {
174 	struct device *dev;
175 	int sid;
176 	bool used;
177 	bool valid;
178 };
179 
180 struct fastrpc_channel_ctx {
181 	int domain_id;
182 	int sesscount;
183 	struct rpmsg_device *rpdev;
184 	struct fastrpc_session_ctx session[FASTRPC_MAX_SESSIONS];
185 	spinlock_t lock;
186 	struct idr ctx_idr;
187 	struct list_head users;
188 	struct miscdevice miscdev;
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 		return -ENOMEM;
284 
285 	if (fl->sctx && fl->sctx->sid)
286 		buf->phys += ((u64)fl->sctx->sid << 32);
287 
288 	*obuf = buf;
289 
290 	return 0;
291 }
292 
293 static void fastrpc_context_free(struct kref *ref)
294 {
295 	struct fastrpc_invoke_ctx *ctx;
296 	struct fastrpc_channel_ctx *cctx;
297 	unsigned long flags;
298 	int i;
299 
300 	ctx = container_of(ref, struct fastrpc_invoke_ctx, refcount);
301 	cctx = ctx->cctx;
302 
303 	for (i = 0; i < ctx->nscalars; i++)
304 		fastrpc_map_put(ctx->maps[i]);
305 
306 	if (ctx->buf)
307 		fastrpc_buf_free(ctx->buf);
308 
309 	spin_lock_irqsave(&cctx->lock, flags);
310 	idr_remove(&cctx->ctx_idr, ctx->ctxid >> 4);
311 	spin_unlock_irqrestore(&cctx->lock, flags);
312 
313 	kfree(ctx->maps);
314 	kfree(ctx->olaps);
315 	kfree(ctx);
316 }
317 
318 static void fastrpc_context_get(struct fastrpc_invoke_ctx *ctx)
319 {
320 	kref_get(&ctx->refcount);
321 }
322 
323 static void fastrpc_context_put(struct fastrpc_invoke_ctx *ctx)
324 {
325 	kref_put(&ctx->refcount, fastrpc_context_free);
326 }
327 
328 static void fastrpc_context_put_wq(struct work_struct *work)
329 {
330 	struct fastrpc_invoke_ctx *ctx =
331 			container_of(work, struct fastrpc_invoke_ctx, put_work);
332 
333 	fastrpc_context_put(ctx);
334 }
335 
336 #define CMP(aa, bb) ((aa) == (bb) ? 0 : (aa) < (bb) ? -1 : 1)
337 static int olaps_cmp(const void *a, const void *b)
338 {
339 	struct fastrpc_buf_overlap *pa = (struct fastrpc_buf_overlap *)a;
340 	struct fastrpc_buf_overlap *pb = (struct fastrpc_buf_overlap *)b;
341 	/* sort with lowest starting buffer first */
342 	int st = CMP(pa->start, pb->start);
343 	/* sort with highest ending buffer first */
344 	int ed = CMP(pb->end, pa->end);
345 
346 	return st == 0 ? ed : st;
347 }
348 
349 static void fastrpc_get_buff_overlaps(struct fastrpc_invoke_ctx *ctx)
350 {
351 	u64 max_end = 0;
352 	int i;
353 
354 	for (i = 0; i < ctx->nbufs; ++i) {
355 		ctx->olaps[i].start = ctx->args[i].ptr;
356 		ctx->olaps[i].end = ctx->olaps[i].start + ctx->args[i].length;
357 		ctx->olaps[i].raix = i;
358 	}
359 
360 	sort(ctx->olaps, ctx->nbufs, sizeof(*ctx->olaps), olaps_cmp, NULL);
361 
362 	for (i = 0; i < ctx->nbufs; ++i) {
363 		/* Falling inside previous range */
364 		if (ctx->olaps[i].start < max_end) {
365 			ctx->olaps[i].mstart = max_end;
366 			ctx->olaps[i].mend = ctx->olaps[i].end;
367 			ctx->olaps[i].offset = max_end - ctx->olaps[i].start;
368 
369 			if (ctx->olaps[i].end > max_end) {
370 				max_end = ctx->olaps[i].end;
371 			} else {
372 				ctx->olaps[i].mend = 0;
373 				ctx->olaps[i].mstart = 0;
374 			}
375 
376 		} else  {
377 			ctx->olaps[i].mend = ctx->olaps[i].end;
378 			ctx->olaps[i].mstart = ctx->olaps[i].start;
379 			ctx->olaps[i].offset = 0;
380 			max_end = ctx->olaps[i].end;
381 		}
382 	}
383 }
384 
385 static struct fastrpc_invoke_ctx *fastrpc_context_alloc(
386 			struct fastrpc_user *user, u32 kernel, u32 sc,
387 			struct fastrpc_invoke_args *args)
388 {
389 	struct fastrpc_channel_ctx *cctx = user->cctx;
390 	struct fastrpc_invoke_ctx *ctx = NULL;
391 	unsigned long flags;
392 	int ret;
393 
394 	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
395 	if (!ctx)
396 		return ERR_PTR(-ENOMEM);
397 
398 	INIT_LIST_HEAD(&ctx->node);
399 	ctx->fl = user;
400 	ctx->nscalars = REMOTE_SCALARS_LENGTH(sc);
401 	ctx->nbufs = REMOTE_SCALARS_INBUFS(sc) +
402 		     REMOTE_SCALARS_OUTBUFS(sc);
403 
404 	if (ctx->nscalars) {
405 		ctx->maps = kcalloc(ctx->nscalars,
406 				    sizeof(*ctx->maps), GFP_KERNEL);
407 		if (!ctx->maps) {
408 			kfree(ctx);
409 			return ERR_PTR(-ENOMEM);
410 		}
411 		ctx->olaps = kcalloc(ctx->nscalars,
412 				    sizeof(*ctx->olaps), GFP_KERNEL);
413 		if (!ctx->olaps) {
414 			kfree(ctx->maps);
415 			kfree(ctx);
416 			return ERR_PTR(-ENOMEM);
417 		}
418 		ctx->args = args;
419 		fastrpc_get_buff_overlaps(ctx);
420 	}
421 
422 	ctx->sc = sc;
423 	ctx->retval = -1;
424 	ctx->pid = current->pid;
425 	ctx->tgid = user->tgid;
426 	ctx->cctx = cctx;
427 	init_completion(&ctx->work);
428 	INIT_WORK(&ctx->put_work, fastrpc_context_put_wq);
429 
430 	spin_lock(&user->lock);
431 	list_add_tail(&ctx->node, &user->pending);
432 	spin_unlock(&user->lock);
433 
434 	spin_lock_irqsave(&cctx->lock, flags);
435 	ret = idr_alloc_cyclic(&cctx->ctx_idr, ctx, 1,
436 			       FASTRPC_CTX_MAX, GFP_ATOMIC);
437 	if (ret < 0) {
438 		spin_unlock_irqrestore(&cctx->lock, flags);
439 		goto err_idr;
440 	}
441 	ctx->ctxid = ret << 4;
442 	spin_unlock_irqrestore(&cctx->lock, flags);
443 
444 	kref_init(&ctx->refcount);
445 
446 	return ctx;
447 err_idr:
448 	spin_lock(&user->lock);
449 	list_del(&ctx->node);
450 	spin_unlock(&user->lock);
451 	kfree(ctx->maps);
452 	kfree(ctx->olaps);
453 	kfree(ctx);
454 
455 	return ERR_PTR(ret);
456 }
457 
458 static struct sg_table *
459 fastrpc_map_dma_buf(struct dma_buf_attachment *attachment,
460 		    enum dma_data_direction dir)
461 {
462 	struct fastrpc_dma_buf_attachment *a = attachment->priv;
463 	struct sg_table *table;
464 
465 	table = &a->sgt;
466 
467 	if (!dma_map_sg(attachment->dev, table->sgl, table->nents, dir))
468 		return ERR_PTR(-ENOMEM);
469 
470 	return table;
471 }
472 
473 static void fastrpc_unmap_dma_buf(struct dma_buf_attachment *attach,
474 				  struct sg_table *table,
475 				  enum dma_data_direction dir)
476 {
477 	dma_unmap_sg(attach->dev, table->sgl, table->nents, dir);
478 }
479 
480 static void fastrpc_release(struct dma_buf *dmabuf)
481 {
482 	struct fastrpc_buf *buffer = dmabuf->priv;
483 
484 	fastrpc_buf_free(buffer);
485 }
486 
487 static int fastrpc_dma_buf_attach(struct dma_buf *dmabuf,
488 				  struct dma_buf_attachment *attachment)
489 {
490 	struct fastrpc_dma_buf_attachment *a;
491 	struct fastrpc_buf *buffer = dmabuf->priv;
492 	int ret;
493 
494 	a = kzalloc(sizeof(*a), GFP_KERNEL);
495 	if (!a)
496 		return -ENOMEM;
497 
498 	ret = dma_get_sgtable(buffer->dev, &a->sgt, buffer->virt,
499 			      FASTRPC_PHYS(buffer->phys), buffer->size);
500 	if (ret < 0) {
501 		dev_err(buffer->dev, "failed to get scatterlist from DMA API\n");
502 		return -EINVAL;
503 	}
504 
505 	a->dev = attachment->dev;
506 	INIT_LIST_HEAD(&a->node);
507 	attachment->priv = a;
508 
509 	mutex_lock(&buffer->lock);
510 	list_add(&a->node, &buffer->attachments);
511 	mutex_unlock(&buffer->lock);
512 
513 	return 0;
514 }
515 
516 static void fastrpc_dma_buf_detatch(struct dma_buf *dmabuf,
517 				    struct dma_buf_attachment *attachment)
518 {
519 	struct fastrpc_dma_buf_attachment *a = attachment->priv;
520 	struct fastrpc_buf *buffer = dmabuf->priv;
521 
522 	mutex_lock(&buffer->lock);
523 	list_del(&a->node);
524 	mutex_unlock(&buffer->lock);
525 	kfree(a);
526 }
527 
528 static void *fastrpc_kmap(struct dma_buf *dmabuf, unsigned long pgnum)
529 {
530 	struct fastrpc_buf *buf = dmabuf->priv;
531 
532 	return buf->virt ? buf->virt + pgnum * PAGE_SIZE : NULL;
533 }
534 
535 static void *fastrpc_vmap(struct dma_buf *dmabuf)
536 {
537 	struct fastrpc_buf *buf = dmabuf->priv;
538 
539 	return buf->virt;
540 }
541 
542 static int fastrpc_mmap(struct dma_buf *dmabuf,
543 			struct vm_area_struct *vma)
544 {
545 	struct fastrpc_buf *buf = dmabuf->priv;
546 	size_t size = vma->vm_end - vma->vm_start;
547 
548 	return dma_mmap_coherent(buf->dev, vma, buf->virt,
549 				 FASTRPC_PHYS(buf->phys), size);
550 }
551 
552 static const struct dma_buf_ops fastrpc_dma_buf_ops = {
553 	.attach = fastrpc_dma_buf_attach,
554 	.detach = fastrpc_dma_buf_detatch,
555 	.map_dma_buf = fastrpc_map_dma_buf,
556 	.unmap_dma_buf = fastrpc_unmap_dma_buf,
557 	.mmap = fastrpc_mmap,
558 	.map = fastrpc_kmap,
559 	.vmap = fastrpc_vmap,
560 	.release = fastrpc_release,
561 };
562 
563 static int fastrpc_map_create(struct fastrpc_user *fl, int fd,
564 			      u64 len, struct fastrpc_map **ppmap)
565 {
566 	struct fastrpc_session_ctx *sess = fl->sctx;
567 	struct fastrpc_map *map = NULL;
568 	int err = 0;
569 
570 	if (!fastrpc_map_find(fl, fd, ppmap))
571 		return 0;
572 
573 	map = kzalloc(sizeof(*map), GFP_KERNEL);
574 	if (!map)
575 		return -ENOMEM;
576 
577 	INIT_LIST_HEAD(&map->node);
578 	map->fl = fl;
579 	map->fd = fd;
580 	map->buf = dma_buf_get(fd);
581 	if (IS_ERR(map->buf)) {
582 		err = PTR_ERR(map->buf);
583 		goto get_err;
584 	}
585 
586 	map->attach = dma_buf_attach(map->buf, sess->dev);
587 	if (IS_ERR(map->attach)) {
588 		dev_err(sess->dev, "Failed to attach dmabuf\n");
589 		err = PTR_ERR(map->attach);
590 		goto attach_err;
591 	}
592 
593 	map->table = dma_buf_map_attachment(map->attach, DMA_BIDIRECTIONAL);
594 	if (IS_ERR(map->table)) {
595 		err = PTR_ERR(map->table);
596 		goto map_err;
597 	}
598 
599 	map->phys = sg_dma_address(map->table->sgl);
600 	map->phys += ((u64)fl->sctx->sid << 32);
601 	map->size = len;
602 	map->va = sg_virt(map->table->sgl);
603 	map->len = len;
604 	kref_init(&map->refcount);
605 
606 	spin_lock(&fl->lock);
607 	list_add_tail(&map->node, &fl->maps);
608 	spin_unlock(&fl->lock);
609 	*ppmap = map;
610 
611 	return 0;
612 
613 map_err:
614 	dma_buf_detach(map->buf, map->attach);
615 attach_err:
616 	dma_buf_put(map->buf);
617 get_err:
618 	kfree(map);
619 
620 	return err;
621 }
622 
623 /*
624  * Fastrpc payload buffer with metadata looks like:
625  *
626  * >>>>>>  START of METADATA <<<<<<<<<
627  * +---------------------------------+
628  * |           Arguments             |
629  * | type:(struct fastrpc_remote_arg)|
630  * |             (0 - N)             |
631  * +---------------------------------+
632  * |         Invoke Buffer list      |
633  * | type:(struct fastrpc_invoke_buf)|
634  * |           (0 - N)               |
635  * +---------------------------------+
636  * |         Page info list          |
637  * | type:(struct fastrpc_phy_page)  |
638  * |             (0 - N)             |
639  * +---------------------------------+
640  * |         Optional info           |
641  * |(can be specific to SoC/Firmware)|
642  * +---------------------------------+
643  * >>>>>>>>  END of METADATA <<<<<<<<<
644  * +---------------------------------+
645  * |         Inline ARGS             |
646  * |            (0-N)                |
647  * +---------------------------------+
648  */
649 
650 static int fastrpc_get_meta_size(struct fastrpc_invoke_ctx *ctx)
651 {
652 	int size = 0;
653 
654 	size = (sizeof(struct fastrpc_remote_arg) +
655 		sizeof(struct fastrpc_invoke_buf) +
656 		sizeof(struct fastrpc_phy_page)) * ctx->nscalars +
657 		sizeof(u64) * FASTRPC_MAX_FDLIST +
658 		sizeof(u32) * FASTRPC_MAX_CRCLIST;
659 
660 	return size;
661 }
662 
663 static u64 fastrpc_get_payload_size(struct fastrpc_invoke_ctx *ctx, int metalen)
664 {
665 	u64 size = 0;
666 	int i;
667 
668 	size = ALIGN(metalen, FASTRPC_ALIGN);
669 	for (i = 0; i < ctx->nscalars; i++) {
670 		if (ctx->args[i].fd == 0 || ctx->args[i].fd == -1) {
671 
672 			if (ctx->olaps[i].offset == 0)
673 				size = ALIGN(size, FASTRPC_ALIGN);
674 
675 			size += (ctx->olaps[i].mend - ctx->olaps[i].mstart);
676 		}
677 	}
678 
679 	return size;
680 }
681 
682 static int fastrpc_create_maps(struct fastrpc_invoke_ctx *ctx)
683 {
684 	struct device *dev = ctx->fl->sctx->dev;
685 	int i, err;
686 
687 	for (i = 0; i < ctx->nscalars; ++i) {
688 		/* Make sure reserved field is set to 0 */
689 		if (ctx->args[i].reserved)
690 			return -EINVAL;
691 
692 		if (ctx->args[i].fd == 0 || ctx->args[i].fd == -1 ||
693 		    ctx->args[i].length == 0)
694 			continue;
695 
696 		err = fastrpc_map_create(ctx->fl, ctx->args[i].fd,
697 					 ctx->args[i].length, &ctx->maps[i]);
698 		if (err) {
699 			dev_err(dev, "Error Creating map %d\n", err);
700 			return -EINVAL;
701 		}
702 
703 	}
704 	return 0;
705 }
706 
707 static int fastrpc_get_args(u32 kernel, struct fastrpc_invoke_ctx *ctx)
708 {
709 	struct device *dev = ctx->fl->sctx->dev;
710 	struct fastrpc_remote_arg *rpra;
711 	struct fastrpc_invoke_buf *list;
712 	struct fastrpc_phy_page *pages;
713 	int inbufs, i, oix, err = 0;
714 	u64 len, rlen, pkt_size;
715 	u64 pg_start, pg_end;
716 	uintptr_t args;
717 	int metalen;
718 
719 	inbufs = REMOTE_SCALARS_INBUFS(ctx->sc);
720 	metalen = fastrpc_get_meta_size(ctx);
721 	pkt_size = fastrpc_get_payload_size(ctx, metalen);
722 
723 	err = fastrpc_create_maps(ctx);
724 	if (err)
725 		return err;
726 
727 	ctx->msg_sz = pkt_size;
728 
729 	err = fastrpc_buf_alloc(ctx->fl, dev, pkt_size, &ctx->buf);
730 	if (err)
731 		return err;
732 
733 	rpra = ctx->buf->virt;
734 	list = ctx->buf->virt + ctx->nscalars * sizeof(*rpra);
735 	pages = ctx->buf->virt + ctx->nscalars * (sizeof(*list) +
736 		sizeof(*rpra));
737 	args = (uintptr_t)ctx->buf->virt + metalen;
738 	rlen = pkt_size - metalen;
739 	ctx->rpra = rpra;
740 
741 	for (oix = 0; oix < ctx->nbufs; ++oix) {
742 		int mlen;
743 
744 		i = ctx->olaps[oix].raix;
745 		len = ctx->args[i].length;
746 
747 		rpra[i].pv = 0;
748 		rpra[i].len = len;
749 		list[i].num = len ? 1 : 0;
750 		list[i].pgidx = i;
751 
752 		if (!len)
753 			continue;
754 
755 		if (ctx->maps[i]) {
756 			struct vm_area_struct *vma = NULL;
757 
758 			rpra[i].pv = (u64) ctx->args[i].ptr;
759 			pages[i].addr = ctx->maps[i]->phys;
760 
761 			vma = find_vma(current->mm, ctx->args[i].ptr);
762 			if (vma)
763 				pages[i].addr += ctx->args[i].ptr -
764 						 vma->vm_start;
765 
766 			pg_start = (ctx->args[i].ptr & PAGE_MASK) >> PAGE_SHIFT;
767 			pg_end = ((ctx->args[i].ptr + len - 1) & PAGE_MASK) >>
768 				  PAGE_SHIFT;
769 			pages[i].size = (pg_end - pg_start + 1) * PAGE_SIZE;
770 
771 		} else {
772 
773 			if (ctx->olaps[oix].offset == 0) {
774 				rlen -= ALIGN(args, FASTRPC_ALIGN) - args;
775 				args = ALIGN(args, FASTRPC_ALIGN);
776 			}
777 
778 			mlen = ctx->olaps[oix].mend - ctx->olaps[oix].mstart;
779 
780 			if (rlen < mlen)
781 				goto bail;
782 
783 			rpra[i].pv = args - ctx->olaps[oix].offset;
784 			pages[i].addr = ctx->buf->phys -
785 					ctx->olaps[oix].offset +
786 					(pkt_size - rlen);
787 			pages[i].addr = pages[i].addr &	PAGE_MASK;
788 
789 			pg_start = (args & PAGE_MASK) >> PAGE_SHIFT;
790 			pg_end = ((args + len - 1) & PAGE_MASK) >> PAGE_SHIFT;
791 			pages[i].size = (pg_end - pg_start + 1) * PAGE_SIZE;
792 			args = args + mlen;
793 			rlen -= mlen;
794 		}
795 
796 		if (i < inbufs && !ctx->maps[i]) {
797 			void *dst = (void *)(uintptr_t)rpra[i].pv;
798 			void *src = (void *)(uintptr_t)ctx->args[i].ptr;
799 
800 			if (!kernel) {
801 				if (copy_from_user(dst, (void __user *)src,
802 						   len)) {
803 					err = -EFAULT;
804 					goto bail;
805 				}
806 			} else {
807 				memcpy(dst, src, len);
808 			}
809 		}
810 	}
811 
812 	for (i = ctx->nbufs; i < ctx->nscalars; ++i) {
813 		rpra[i].pv = (u64) ctx->args[i].ptr;
814 		rpra[i].len = ctx->args[i].length;
815 		list[i].num = ctx->args[i].length ? 1 : 0;
816 		list[i].pgidx = i;
817 		pages[i].addr = ctx->maps[i]->phys;
818 		pages[i].size = ctx->maps[i]->size;
819 	}
820 
821 bail:
822 	if (err)
823 		dev_err(dev, "Error: get invoke args failed:%d\n", err);
824 
825 	return err;
826 }
827 
828 static int fastrpc_put_args(struct fastrpc_invoke_ctx *ctx,
829 			    u32 kernel)
830 {
831 	struct fastrpc_remote_arg *rpra = ctx->rpra;
832 	int i, inbufs;
833 
834 	inbufs = REMOTE_SCALARS_INBUFS(ctx->sc);
835 
836 	for (i = inbufs; i < ctx->nbufs; ++i) {
837 		void *src = (void *)(uintptr_t)rpra[i].pv;
838 		void *dst = (void *)(uintptr_t)ctx->args[i].ptr;
839 		u64 len = rpra[i].len;
840 
841 		if (!kernel) {
842 			if (copy_to_user((void __user *)dst, src, len))
843 				return -EFAULT;
844 		} else {
845 			memcpy(dst, src, len);
846 		}
847 	}
848 
849 	return 0;
850 }
851 
852 static int fastrpc_invoke_send(struct fastrpc_session_ctx *sctx,
853 			       struct fastrpc_invoke_ctx *ctx,
854 			       u32 kernel, uint32_t handle)
855 {
856 	struct fastrpc_channel_ctx *cctx;
857 	struct fastrpc_user *fl = ctx->fl;
858 	struct fastrpc_msg *msg = &ctx->msg;
859 
860 	cctx = fl->cctx;
861 	msg->pid = fl->tgid;
862 	msg->tid = current->pid;
863 
864 	if (kernel)
865 		msg->pid = 0;
866 
867 	msg->ctx = ctx->ctxid | fl->pd;
868 	msg->handle = handle;
869 	msg->sc = ctx->sc;
870 	msg->addr = ctx->buf ? ctx->buf->phys : 0;
871 	msg->size = roundup(ctx->msg_sz, PAGE_SIZE);
872 	fastrpc_context_get(ctx);
873 
874 	return rpmsg_send(cctx->rpdev->ept, (void *)msg, sizeof(*msg));
875 }
876 
877 static int fastrpc_internal_invoke(struct fastrpc_user *fl,  u32 kernel,
878 				   u32 handle, u32 sc,
879 				   struct fastrpc_invoke_args *args)
880 {
881 	struct fastrpc_invoke_ctx *ctx = NULL;
882 	int err = 0;
883 
884 	if (!fl->sctx)
885 		return -EINVAL;
886 
887 	ctx = fastrpc_context_alloc(fl, kernel, sc, args);
888 	if (IS_ERR(ctx))
889 		return PTR_ERR(ctx);
890 
891 	if (ctx->nscalars) {
892 		err = fastrpc_get_args(kernel, ctx);
893 		if (err)
894 			goto bail;
895 	}
896 
897 	/* make sure that all CPU memory writes are seen by DSP */
898 	dma_wmb();
899 	/* Send invoke buffer to remote dsp */
900 	err = fastrpc_invoke_send(fl->sctx, ctx, kernel, handle);
901 	if (err)
902 		goto bail;
903 
904 	/* Wait for remote dsp to respond or time out */
905 	err = wait_for_completion_interruptible(&ctx->work);
906 	if (err)
907 		goto bail;
908 
909 	/* Check the response from remote dsp */
910 	err = ctx->retval;
911 	if (err)
912 		goto bail;
913 
914 	if (ctx->nscalars) {
915 		/* make sure that all memory writes by DSP are seen by CPU */
916 		dma_rmb();
917 		/* populate all the output buffers with results */
918 		err = fastrpc_put_args(ctx, kernel);
919 		if (err)
920 			goto bail;
921 	}
922 
923 bail:
924 	/* We are done with this compute context, remove it from pending list */
925 	spin_lock(&fl->lock);
926 	list_del(&ctx->node);
927 	spin_unlock(&fl->lock);
928 	fastrpc_context_put(ctx);
929 
930 	if (err)
931 		dev_dbg(fl->sctx->dev, "Error: Invoke Failed %d\n", err);
932 
933 	return err;
934 }
935 
936 static int fastrpc_init_create_process(struct fastrpc_user *fl,
937 					char __user *argp)
938 {
939 	struct fastrpc_init_create init;
940 	struct fastrpc_invoke_args *args;
941 	struct fastrpc_phy_page pages[1];
942 	struct fastrpc_map *map = NULL;
943 	struct fastrpc_buf *imem = NULL;
944 	int memlen;
945 	int err;
946 	struct {
947 		int pgid;
948 		u32 namelen;
949 		u32 filelen;
950 		u32 pageslen;
951 		u32 attrs;
952 		u32 siglen;
953 	} inbuf;
954 	u32 sc;
955 
956 	args = kcalloc(FASTRPC_CREATE_PROCESS_NARGS, sizeof(*args), GFP_KERNEL);
957 	if (!args)
958 		return -ENOMEM;
959 
960 	if (copy_from_user(&init, argp, sizeof(init))) {
961 		err = -EFAULT;
962 		goto err;
963 	}
964 
965 	if (init.filelen > INIT_FILELEN_MAX) {
966 		err = -EINVAL;
967 		goto err;
968 	}
969 
970 	inbuf.pgid = fl->tgid;
971 	inbuf.namelen = strlen(current->comm) + 1;
972 	inbuf.filelen = init.filelen;
973 	inbuf.pageslen = 1;
974 	inbuf.attrs = init.attrs;
975 	inbuf.siglen = init.siglen;
976 	fl->pd = 1;
977 
978 	if (init.filelen && init.filefd) {
979 		err = fastrpc_map_create(fl, init.filefd, init.filelen, &map);
980 		if (err)
981 			goto err;
982 	}
983 
984 	memlen = ALIGN(max(INIT_FILELEN_MAX, (int)init.filelen * 4),
985 		       1024 * 1024);
986 	err = fastrpc_buf_alloc(fl, fl->sctx->dev, memlen,
987 				&imem);
988 	if (err)
989 		goto err_alloc;
990 
991 	fl->init_mem = imem;
992 	args[0].ptr = (u64)(uintptr_t)&inbuf;
993 	args[0].length = sizeof(inbuf);
994 	args[0].fd = -1;
995 
996 	args[1].ptr = (u64)(uintptr_t)current->comm;
997 	args[1].length = inbuf.namelen;
998 	args[1].fd = -1;
999 
1000 	args[2].ptr = (u64) init.file;
1001 	args[2].length = inbuf.filelen;
1002 	args[2].fd = init.filefd;
1003 
1004 	pages[0].addr = imem->phys;
1005 	pages[0].size = imem->size;
1006 
1007 	args[3].ptr = (u64)(uintptr_t) pages;
1008 	args[3].length = 1 * sizeof(*pages);
1009 	args[3].fd = -1;
1010 
1011 	args[4].ptr = (u64)(uintptr_t)&inbuf.attrs;
1012 	args[4].length = sizeof(inbuf.attrs);
1013 	args[4].fd = -1;
1014 
1015 	args[5].ptr = (u64)(uintptr_t) &inbuf.siglen;
1016 	args[5].length = sizeof(inbuf.siglen);
1017 	args[5].fd = -1;
1018 
1019 	sc = FASTRPC_SCALARS(FASTRPC_RMID_INIT_CREATE, 4, 0);
1020 	if (init.attrs)
1021 		sc = FASTRPC_SCALARS(FASTRPC_RMID_INIT_CREATE_ATTR, 6, 0);
1022 
1023 	err = fastrpc_internal_invoke(fl, true, FASTRPC_INIT_HANDLE,
1024 				      sc, args);
1025 	if (err)
1026 		goto err_invoke;
1027 
1028 	kfree(args);
1029 
1030 	return 0;
1031 
1032 err_invoke:
1033 	fl->init_mem = NULL;
1034 	fastrpc_buf_free(imem);
1035 err_alloc:
1036 	if (map) {
1037 		spin_lock(&fl->lock);
1038 		list_del(&map->node);
1039 		spin_unlock(&fl->lock);
1040 		fastrpc_map_put(map);
1041 	}
1042 err:
1043 	kfree(args);
1044 
1045 	return err;
1046 }
1047 
1048 static struct fastrpc_session_ctx *fastrpc_session_alloc(
1049 					struct fastrpc_channel_ctx *cctx)
1050 {
1051 	struct fastrpc_session_ctx *session = NULL;
1052 	unsigned long flags;
1053 	int i;
1054 
1055 	spin_lock_irqsave(&cctx->lock, flags);
1056 	for (i = 0; i < cctx->sesscount; i++) {
1057 		if (!cctx->session[i].used && cctx->session[i].valid) {
1058 			cctx->session[i].used = true;
1059 			session = &cctx->session[i];
1060 			break;
1061 		}
1062 	}
1063 	spin_unlock_irqrestore(&cctx->lock, flags);
1064 
1065 	return session;
1066 }
1067 
1068 static void fastrpc_session_free(struct fastrpc_channel_ctx *cctx,
1069 				 struct fastrpc_session_ctx *session)
1070 {
1071 	unsigned long flags;
1072 
1073 	spin_lock_irqsave(&cctx->lock, flags);
1074 	session->used = false;
1075 	spin_unlock_irqrestore(&cctx->lock, flags);
1076 }
1077 
1078 static int fastrpc_release_current_dsp_process(struct fastrpc_user *fl)
1079 {
1080 	struct fastrpc_invoke_args args[1];
1081 	int tgid = 0;
1082 	u32 sc;
1083 
1084 	tgid = fl->tgid;
1085 	args[0].ptr = (u64)(uintptr_t) &tgid;
1086 	args[0].length = sizeof(tgid);
1087 	args[0].fd = -1;
1088 	args[0].reserved = 0;
1089 	sc = FASTRPC_SCALARS(FASTRPC_RMID_INIT_RELEASE, 1, 0);
1090 
1091 	return fastrpc_internal_invoke(fl, true, FASTRPC_INIT_HANDLE,
1092 				       sc, &args[0]);
1093 }
1094 
1095 static int fastrpc_device_release(struct inode *inode, struct file *file)
1096 {
1097 	struct fastrpc_user *fl = (struct fastrpc_user *)file->private_data;
1098 	struct fastrpc_channel_ctx *cctx = fl->cctx;
1099 	struct fastrpc_invoke_ctx *ctx, *n;
1100 	struct fastrpc_map *map, *m;
1101 	unsigned long flags;
1102 
1103 	fastrpc_release_current_dsp_process(fl);
1104 
1105 	spin_lock_irqsave(&cctx->lock, flags);
1106 	list_del(&fl->user);
1107 	spin_unlock_irqrestore(&cctx->lock, flags);
1108 
1109 	if (fl->init_mem)
1110 		fastrpc_buf_free(fl->init_mem);
1111 
1112 	list_for_each_entry_safe(ctx, n, &fl->pending, node) {
1113 		list_del(&ctx->node);
1114 		fastrpc_context_put(ctx);
1115 	}
1116 
1117 	list_for_each_entry_safe(map, m, &fl->maps, node) {
1118 		list_del(&map->node);
1119 		fastrpc_map_put(map);
1120 	}
1121 
1122 	fastrpc_session_free(cctx, fl->sctx);
1123 
1124 	mutex_destroy(&fl->mutex);
1125 	kfree(fl);
1126 	file->private_data = NULL;
1127 
1128 	return 0;
1129 }
1130 
1131 static int fastrpc_device_open(struct inode *inode, struct file *filp)
1132 {
1133 	struct fastrpc_channel_ctx *cctx = miscdev_to_cctx(filp->private_data);
1134 	struct fastrpc_user *fl = NULL;
1135 	unsigned long flags;
1136 
1137 	fl = kzalloc(sizeof(*fl), GFP_KERNEL);
1138 	if (!fl)
1139 		return -ENOMEM;
1140 
1141 	filp->private_data = fl;
1142 	spin_lock_init(&fl->lock);
1143 	mutex_init(&fl->mutex);
1144 	INIT_LIST_HEAD(&fl->pending);
1145 	INIT_LIST_HEAD(&fl->maps);
1146 	INIT_LIST_HEAD(&fl->user);
1147 	fl->tgid = current->tgid;
1148 	fl->cctx = cctx;
1149 
1150 	fl->sctx = fastrpc_session_alloc(cctx);
1151 	if (!fl->sctx) {
1152 		dev_err(&cctx->rpdev->dev, "No session available\n");
1153 		mutex_destroy(&fl->mutex);
1154 		kfree(fl);
1155 
1156 		return -EBUSY;
1157 	}
1158 
1159 	spin_lock_irqsave(&cctx->lock, flags);
1160 	list_add_tail(&fl->user, &cctx->users);
1161 	spin_unlock_irqrestore(&cctx->lock, flags);
1162 
1163 	return 0;
1164 }
1165 
1166 static int fastrpc_dmabuf_free(struct fastrpc_user *fl, char __user *argp)
1167 {
1168 	struct dma_buf *buf;
1169 	int info;
1170 
1171 	if (copy_from_user(&info, argp, sizeof(info)))
1172 		return -EFAULT;
1173 
1174 	buf = dma_buf_get(info);
1175 	if (IS_ERR_OR_NULL(buf))
1176 		return -EINVAL;
1177 	/*
1178 	 * one for the last get and other for the ALLOC_DMA_BUFF ioctl
1179 	 */
1180 	dma_buf_put(buf);
1181 	dma_buf_put(buf);
1182 
1183 	return 0;
1184 }
1185 
1186 static int fastrpc_dmabuf_alloc(struct fastrpc_user *fl, char __user *argp)
1187 {
1188 	struct fastrpc_alloc_dma_buf bp;
1189 	DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
1190 	struct fastrpc_buf *buf = NULL;
1191 	int err;
1192 
1193 	if (copy_from_user(&bp, argp, sizeof(bp)))
1194 		return -EFAULT;
1195 
1196 	err = fastrpc_buf_alloc(fl, fl->sctx->dev, bp.size, &buf);
1197 	if (err)
1198 		return err;
1199 	exp_info.ops = &fastrpc_dma_buf_ops;
1200 	exp_info.size = bp.size;
1201 	exp_info.flags = O_RDWR;
1202 	exp_info.priv = buf;
1203 	buf->dmabuf = dma_buf_export(&exp_info);
1204 	if (IS_ERR(buf->dmabuf)) {
1205 		err = PTR_ERR(buf->dmabuf);
1206 		fastrpc_buf_free(buf);
1207 		return err;
1208 	}
1209 
1210 	bp.fd = dma_buf_fd(buf->dmabuf, O_ACCMODE);
1211 	if (bp.fd < 0) {
1212 		dma_buf_put(buf->dmabuf);
1213 		return -EINVAL;
1214 	}
1215 
1216 	if (copy_to_user(argp, &bp, sizeof(bp))) {
1217 		dma_buf_put(buf->dmabuf);
1218 		return -EFAULT;
1219 	}
1220 
1221 	get_dma_buf(buf->dmabuf);
1222 
1223 	return 0;
1224 }
1225 
1226 static int fastrpc_init_attach(struct fastrpc_user *fl)
1227 {
1228 	struct fastrpc_invoke_args args[1];
1229 	int tgid = fl->tgid;
1230 	u32 sc;
1231 
1232 	args[0].ptr = (u64)(uintptr_t) &tgid;
1233 	args[0].length = sizeof(tgid);
1234 	args[0].fd = -1;
1235 	args[0].reserved = 0;
1236 	sc = FASTRPC_SCALARS(FASTRPC_RMID_INIT_ATTACH, 1, 0);
1237 	fl->pd = 0;
1238 
1239 	return fastrpc_internal_invoke(fl, true, FASTRPC_INIT_HANDLE,
1240 				       sc, &args[0]);
1241 }
1242 
1243 static int fastrpc_invoke(struct fastrpc_user *fl, char __user *argp)
1244 {
1245 	struct fastrpc_invoke_args *args = NULL;
1246 	struct fastrpc_invoke inv;
1247 	u32 nscalars;
1248 	int err;
1249 
1250 	if (copy_from_user(&inv, argp, sizeof(inv)))
1251 		return -EFAULT;
1252 
1253 	/* nscalars is truncated here to max supported value */
1254 	nscalars = REMOTE_SCALARS_LENGTH(inv.sc);
1255 	if (nscalars) {
1256 		args = kcalloc(nscalars, sizeof(*args), GFP_KERNEL);
1257 		if (!args)
1258 			return -ENOMEM;
1259 
1260 		if (copy_from_user(args, (void __user *)(uintptr_t)inv.args,
1261 				   nscalars * sizeof(*args))) {
1262 			kfree(args);
1263 			return -EFAULT;
1264 		}
1265 	}
1266 
1267 	err = fastrpc_internal_invoke(fl, false, inv.handle, inv.sc, args);
1268 	kfree(args);
1269 
1270 	return err;
1271 }
1272 
1273 static long fastrpc_device_ioctl(struct file *file, unsigned int cmd,
1274 				 unsigned long arg)
1275 {
1276 	struct fastrpc_user *fl = (struct fastrpc_user *)file->private_data;
1277 	char __user *argp = (char __user *)arg;
1278 	int err;
1279 
1280 	switch (cmd) {
1281 	case FASTRPC_IOCTL_INVOKE:
1282 		err = fastrpc_invoke(fl, argp);
1283 		break;
1284 	case FASTRPC_IOCTL_INIT_ATTACH:
1285 		err = fastrpc_init_attach(fl);
1286 		break;
1287 	case FASTRPC_IOCTL_INIT_CREATE:
1288 		err = fastrpc_init_create_process(fl, argp);
1289 		break;
1290 	case FASTRPC_IOCTL_FREE_DMA_BUFF:
1291 		err = fastrpc_dmabuf_free(fl, argp);
1292 		break;
1293 	case FASTRPC_IOCTL_ALLOC_DMA_BUFF:
1294 		err = fastrpc_dmabuf_alloc(fl, argp);
1295 		break;
1296 	default:
1297 		err = -ENOTTY;
1298 		break;
1299 	}
1300 
1301 	return err;
1302 }
1303 
1304 static const struct file_operations fastrpc_fops = {
1305 	.open = fastrpc_device_open,
1306 	.release = fastrpc_device_release,
1307 	.unlocked_ioctl = fastrpc_device_ioctl,
1308 	.compat_ioctl = fastrpc_device_ioctl,
1309 };
1310 
1311 static int fastrpc_cb_probe(struct platform_device *pdev)
1312 {
1313 	struct fastrpc_channel_ctx *cctx;
1314 	struct fastrpc_session_ctx *sess;
1315 	struct device *dev = &pdev->dev;
1316 	int i, sessions = 0;
1317 	unsigned long flags;
1318 	int rc;
1319 
1320 	cctx = dev_get_drvdata(dev->parent);
1321 	if (!cctx)
1322 		return -EINVAL;
1323 
1324 	of_property_read_u32(dev->of_node, "qcom,nsessions", &sessions);
1325 
1326 	spin_lock_irqsave(&cctx->lock, flags);
1327 	sess = &cctx->session[cctx->sesscount];
1328 	sess->used = false;
1329 	sess->valid = true;
1330 	sess->dev = dev;
1331 	dev_set_drvdata(dev, sess);
1332 
1333 	if (of_property_read_u32(dev->of_node, "reg", &sess->sid))
1334 		dev_info(dev, "FastRPC Session ID not specified in DT\n");
1335 
1336 	if (sessions > 0) {
1337 		struct fastrpc_session_ctx *dup_sess;
1338 
1339 		for (i = 1; i < sessions; i++) {
1340 			if (cctx->sesscount++ >= FASTRPC_MAX_SESSIONS)
1341 				break;
1342 			dup_sess = &cctx->session[cctx->sesscount];
1343 			memcpy(dup_sess, sess, sizeof(*dup_sess));
1344 		}
1345 	}
1346 	cctx->sesscount++;
1347 	spin_unlock_irqrestore(&cctx->lock, flags);
1348 	rc = dma_set_mask(dev, DMA_BIT_MASK(32));
1349 	if (rc) {
1350 		dev_err(dev, "32-bit DMA enable failed\n");
1351 		return rc;
1352 	}
1353 
1354 	return 0;
1355 }
1356 
1357 static int fastrpc_cb_remove(struct platform_device *pdev)
1358 {
1359 	struct fastrpc_channel_ctx *cctx = dev_get_drvdata(pdev->dev.parent);
1360 	struct fastrpc_session_ctx *sess = dev_get_drvdata(&pdev->dev);
1361 	unsigned long flags;
1362 	int i;
1363 
1364 	spin_lock_irqsave(&cctx->lock, flags);
1365 	for (i = 1; i < FASTRPC_MAX_SESSIONS; i++) {
1366 		if (cctx->session[i].sid == sess->sid) {
1367 			cctx->session[i].valid = false;
1368 			cctx->sesscount--;
1369 		}
1370 	}
1371 	spin_unlock_irqrestore(&cctx->lock, flags);
1372 
1373 	return 0;
1374 }
1375 
1376 static const struct of_device_id fastrpc_match_table[] = {
1377 	{ .compatible = "qcom,fastrpc-compute-cb", },
1378 	{}
1379 };
1380 
1381 static struct platform_driver fastrpc_cb_driver = {
1382 	.probe = fastrpc_cb_probe,
1383 	.remove = fastrpc_cb_remove,
1384 	.driver = {
1385 		.name = "qcom,fastrpc-cb",
1386 		.of_match_table = fastrpc_match_table,
1387 		.suppress_bind_attrs = true,
1388 	},
1389 };
1390 
1391 static int fastrpc_rpmsg_probe(struct rpmsg_device *rpdev)
1392 {
1393 	struct device *rdev = &rpdev->dev;
1394 	struct fastrpc_channel_ctx *data;
1395 	int i, err, domain_id = -1;
1396 	const char *domain;
1397 
1398 	data = devm_kzalloc(rdev, sizeof(*data), GFP_KERNEL);
1399 	if (!data)
1400 		return -ENOMEM;
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->miscdev.minor = MISC_DYNAMIC_MINOR;
1421 	data->miscdev.name = kasprintf(GFP_KERNEL, "fastrpc-%s",
1422 				domains[domain_id]);
1423 	data->miscdev.fops = &fastrpc_fops;
1424 	err = misc_register(&data->miscdev);
1425 	if (err)
1426 		return err;
1427 
1428 	dev_set_drvdata(&rpdev->dev, data);
1429 	dma_set_mask_and_coherent(rdev, DMA_BIT_MASK(32));
1430 	INIT_LIST_HEAD(&data->users);
1431 	spin_lock_init(&data->lock);
1432 	idr_init(&data->ctx_idr);
1433 	data->domain_id = domain_id;
1434 	data->rpdev = rpdev;
1435 
1436 	return of_platform_populate(rdev->of_node, NULL, NULL, rdev);
1437 }
1438 
1439 static void fastrpc_notify_users(struct fastrpc_user *user)
1440 {
1441 	struct fastrpc_invoke_ctx *ctx;
1442 
1443 	spin_lock(&user->lock);
1444 	list_for_each_entry(ctx, &user->pending, node)
1445 		complete(&ctx->work);
1446 	spin_unlock(&user->lock);
1447 }
1448 
1449 static void fastrpc_rpmsg_remove(struct rpmsg_device *rpdev)
1450 {
1451 	struct fastrpc_channel_ctx *cctx = dev_get_drvdata(&rpdev->dev);
1452 	struct fastrpc_user *user;
1453 	unsigned long flags;
1454 
1455 	spin_lock_irqsave(&cctx->lock, flags);
1456 	list_for_each_entry(user, &cctx->users, user)
1457 		fastrpc_notify_users(user);
1458 	spin_unlock_irqrestore(&cctx->lock, flags);
1459 
1460 	misc_deregister(&cctx->miscdev);
1461 	of_platform_depopulate(&rpdev->dev);
1462 	kfree(cctx);
1463 }
1464 
1465 static int fastrpc_rpmsg_callback(struct rpmsg_device *rpdev, void *data,
1466 				  int len, void *priv, u32 addr)
1467 {
1468 	struct fastrpc_channel_ctx *cctx = dev_get_drvdata(&rpdev->dev);
1469 	struct fastrpc_invoke_rsp *rsp = data;
1470 	struct fastrpc_invoke_ctx *ctx;
1471 	unsigned long flags;
1472 	unsigned long ctxid;
1473 
1474 	if (len < sizeof(*rsp))
1475 		return -EINVAL;
1476 
1477 	ctxid = ((rsp->ctx & FASTRPC_CTXID_MASK) >> 4);
1478 
1479 	spin_lock_irqsave(&cctx->lock, flags);
1480 	ctx = idr_find(&cctx->ctx_idr, ctxid);
1481 	spin_unlock_irqrestore(&cctx->lock, flags);
1482 
1483 	if (!ctx) {
1484 		dev_err(&rpdev->dev, "No context ID matches response\n");
1485 		return -ENOENT;
1486 	}
1487 
1488 	ctx->retval = rsp->retval;
1489 	complete(&ctx->work);
1490 
1491 	/*
1492 	 * The DMA buffer associated with the context cannot be freed in
1493 	 * interrupt context so schedule it through a worker thread to
1494 	 * avoid a kernel BUG.
1495 	 */
1496 	schedule_work(&ctx->put_work);
1497 
1498 	return 0;
1499 }
1500 
1501 static const struct of_device_id fastrpc_rpmsg_of_match[] = {
1502 	{ .compatible = "qcom,fastrpc" },
1503 	{ },
1504 };
1505 MODULE_DEVICE_TABLE(of, fastrpc_rpmsg_of_match);
1506 
1507 static struct rpmsg_driver fastrpc_driver = {
1508 	.probe = fastrpc_rpmsg_probe,
1509 	.remove = fastrpc_rpmsg_remove,
1510 	.callback = fastrpc_rpmsg_callback,
1511 	.drv = {
1512 		.name = "qcom,fastrpc",
1513 		.of_match_table = fastrpc_rpmsg_of_match,
1514 	},
1515 };
1516 
1517 static int fastrpc_init(void)
1518 {
1519 	int ret;
1520 
1521 	ret = platform_driver_register(&fastrpc_cb_driver);
1522 	if (ret < 0) {
1523 		pr_err("fastrpc: failed to register cb driver\n");
1524 		return ret;
1525 	}
1526 
1527 	ret = register_rpmsg_driver(&fastrpc_driver);
1528 	if (ret < 0) {
1529 		pr_err("fastrpc: failed to register rpmsg driver\n");
1530 		platform_driver_unregister(&fastrpc_cb_driver);
1531 		return ret;
1532 	}
1533 
1534 	return 0;
1535 }
1536 module_init(fastrpc_init);
1537 
1538 static void fastrpc_exit(void)
1539 {
1540 	platform_driver_unregister(&fastrpc_cb_driver);
1541 	unregister_rpmsg_driver(&fastrpc_driver);
1542 }
1543 module_exit(fastrpc_exit);
1544 
1545 MODULE_LICENSE("GPL v2");
1546