xref: /openbmc/linux/drivers/misc/fastrpc.c (revision e6f4c346)
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 		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_context_free(struct kref *ref)
297 {
298 	struct fastrpc_invoke_ctx *ctx;
299 	struct fastrpc_channel_ctx *cctx;
300 	unsigned long flags;
301 	int i;
302 
303 	ctx = container_of(ref, struct fastrpc_invoke_ctx, refcount);
304 	cctx = ctx->cctx;
305 
306 	for (i = 0; i < ctx->nscalars; i++)
307 		fastrpc_map_put(ctx->maps[i]);
308 
309 	if (ctx->buf)
310 		fastrpc_buf_free(ctx->buf);
311 
312 	spin_lock_irqsave(&cctx->lock, flags);
313 	idr_remove(&cctx->ctx_idr, ctx->ctxid >> 4);
314 	spin_unlock_irqrestore(&cctx->lock, flags);
315 
316 	kfree(ctx->maps);
317 	kfree(ctx->olaps);
318 	kfree(ctx);
319 }
320 
321 static void fastrpc_context_get(struct fastrpc_invoke_ctx *ctx)
322 {
323 	kref_get(&ctx->refcount);
324 }
325 
326 static void fastrpc_context_put(struct fastrpc_invoke_ctx *ctx)
327 {
328 	kref_put(&ctx->refcount, fastrpc_context_free);
329 }
330 
331 static void fastrpc_context_put_wq(struct work_struct *work)
332 {
333 	struct fastrpc_invoke_ctx *ctx =
334 			container_of(work, struct fastrpc_invoke_ctx, put_work);
335 
336 	fastrpc_context_put(ctx);
337 }
338 
339 #define CMP(aa, bb) ((aa) == (bb) ? 0 : (aa) < (bb) ? -1 : 1)
340 static int olaps_cmp(const void *a, const void *b)
341 {
342 	struct fastrpc_buf_overlap *pa = (struct fastrpc_buf_overlap *)a;
343 	struct fastrpc_buf_overlap *pb = (struct fastrpc_buf_overlap *)b;
344 	/* sort with lowest starting buffer first */
345 	int st = CMP(pa->start, pb->start);
346 	/* sort with highest ending buffer first */
347 	int ed = CMP(pb->end, pa->end);
348 
349 	return st == 0 ? ed : st;
350 }
351 
352 static void fastrpc_get_buff_overlaps(struct fastrpc_invoke_ctx *ctx)
353 {
354 	u64 max_end = 0;
355 	int i;
356 
357 	for (i = 0; i < ctx->nbufs; ++i) {
358 		ctx->olaps[i].start = ctx->args[i].ptr;
359 		ctx->olaps[i].end = ctx->olaps[i].start + ctx->args[i].length;
360 		ctx->olaps[i].raix = i;
361 	}
362 
363 	sort(ctx->olaps, ctx->nbufs, sizeof(*ctx->olaps), olaps_cmp, NULL);
364 
365 	for (i = 0; i < ctx->nbufs; ++i) {
366 		/* Falling inside previous range */
367 		if (ctx->olaps[i].start < max_end) {
368 			ctx->olaps[i].mstart = max_end;
369 			ctx->olaps[i].mend = ctx->olaps[i].end;
370 			ctx->olaps[i].offset = max_end - ctx->olaps[i].start;
371 
372 			if (ctx->olaps[i].end > max_end) {
373 				max_end = ctx->olaps[i].end;
374 			} else {
375 				ctx->olaps[i].mend = 0;
376 				ctx->olaps[i].mstart = 0;
377 			}
378 
379 		} else  {
380 			ctx->olaps[i].mend = ctx->olaps[i].end;
381 			ctx->olaps[i].mstart = ctx->olaps[i].start;
382 			ctx->olaps[i].offset = 0;
383 			max_end = ctx->olaps[i].end;
384 		}
385 	}
386 }
387 
388 static struct fastrpc_invoke_ctx *fastrpc_context_alloc(
389 			struct fastrpc_user *user, u32 kernel, u32 sc,
390 			struct fastrpc_invoke_args *args)
391 {
392 	struct fastrpc_channel_ctx *cctx = user->cctx;
393 	struct fastrpc_invoke_ctx *ctx = NULL;
394 	unsigned long flags;
395 	int ret;
396 
397 	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
398 	if (!ctx)
399 		return ERR_PTR(-ENOMEM);
400 
401 	INIT_LIST_HEAD(&ctx->node);
402 	ctx->fl = user;
403 	ctx->nscalars = REMOTE_SCALARS_LENGTH(sc);
404 	ctx->nbufs = REMOTE_SCALARS_INBUFS(sc) +
405 		     REMOTE_SCALARS_OUTBUFS(sc);
406 
407 	if (ctx->nscalars) {
408 		ctx->maps = kcalloc(ctx->nscalars,
409 				    sizeof(*ctx->maps), GFP_KERNEL);
410 		if (!ctx->maps) {
411 			kfree(ctx);
412 			return ERR_PTR(-ENOMEM);
413 		}
414 		ctx->olaps = kcalloc(ctx->nscalars,
415 				    sizeof(*ctx->olaps), GFP_KERNEL);
416 		if (!ctx->olaps) {
417 			kfree(ctx->maps);
418 			kfree(ctx);
419 			return ERR_PTR(-ENOMEM);
420 		}
421 		ctx->args = args;
422 		fastrpc_get_buff_overlaps(ctx);
423 	}
424 
425 	ctx->sc = sc;
426 	ctx->retval = -1;
427 	ctx->pid = current->pid;
428 	ctx->tgid = user->tgid;
429 	ctx->cctx = cctx;
430 	init_completion(&ctx->work);
431 	INIT_WORK(&ctx->put_work, fastrpc_context_put_wq);
432 
433 	spin_lock(&user->lock);
434 	list_add_tail(&ctx->node, &user->pending);
435 	spin_unlock(&user->lock);
436 
437 	spin_lock_irqsave(&cctx->lock, flags);
438 	ret = idr_alloc_cyclic(&cctx->ctx_idr, ctx, 1,
439 			       FASTRPC_CTX_MAX, GFP_ATOMIC);
440 	if (ret < 0) {
441 		spin_unlock_irqrestore(&cctx->lock, flags);
442 		goto err_idr;
443 	}
444 	ctx->ctxid = ret << 4;
445 	spin_unlock_irqrestore(&cctx->lock, flags);
446 
447 	kref_init(&ctx->refcount);
448 
449 	return ctx;
450 err_idr:
451 	spin_lock(&user->lock);
452 	list_del(&ctx->node);
453 	spin_unlock(&user->lock);
454 	kfree(ctx->maps);
455 	kfree(ctx->olaps);
456 	kfree(ctx);
457 
458 	return ERR_PTR(ret);
459 }
460 
461 static struct sg_table *
462 fastrpc_map_dma_buf(struct dma_buf_attachment *attachment,
463 		    enum dma_data_direction dir)
464 {
465 	struct fastrpc_dma_buf_attachment *a = attachment->priv;
466 	struct sg_table *table;
467 
468 	table = &a->sgt;
469 
470 	if (!dma_map_sg(attachment->dev, table->sgl, table->nents, dir))
471 		return ERR_PTR(-ENOMEM);
472 
473 	return table;
474 }
475 
476 static void fastrpc_unmap_dma_buf(struct dma_buf_attachment *attach,
477 				  struct sg_table *table,
478 				  enum dma_data_direction dir)
479 {
480 	dma_unmap_sg(attach->dev, table->sgl, table->nents, dir);
481 }
482 
483 static void fastrpc_release(struct dma_buf *dmabuf)
484 {
485 	struct fastrpc_buf *buffer = dmabuf->priv;
486 
487 	fastrpc_buf_free(buffer);
488 }
489 
490 static int fastrpc_dma_buf_attach(struct dma_buf *dmabuf,
491 				  struct dma_buf_attachment *attachment)
492 {
493 	struct fastrpc_dma_buf_attachment *a;
494 	struct fastrpc_buf *buffer = dmabuf->priv;
495 	int ret;
496 
497 	a = kzalloc(sizeof(*a), GFP_KERNEL);
498 	if (!a)
499 		return -ENOMEM;
500 
501 	ret = dma_get_sgtable(buffer->dev, &a->sgt, buffer->virt,
502 			      FASTRPC_PHYS(buffer->phys), buffer->size);
503 	if (ret < 0) {
504 		dev_err(buffer->dev, "failed to get scatterlist from DMA API\n");
505 		return -EINVAL;
506 	}
507 
508 	a->dev = attachment->dev;
509 	INIT_LIST_HEAD(&a->node);
510 	attachment->priv = a;
511 
512 	mutex_lock(&buffer->lock);
513 	list_add(&a->node, &buffer->attachments);
514 	mutex_unlock(&buffer->lock);
515 
516 	return 0;
517 }
518 
519 static void fastrpc_dma_buf_detatch(struct dma_buf *dmabuf,
520 				    struct dma_buf_attachment *attachment)
521 {
522 	struct fastrpc_dma_buf_attachment *a = attachment->priv;
523 	struct fastrpc_buf *buffer = dmabuf->priv;
524 
525 	mutex_lock(&buffer->lock);
526 	list_del(&a->node);
527 	mutex_unlock(&buffer->lock);
528 	kfree(a);
529 }
530 
531 static void *fastrpc_kmap(struct dma_buf *dmabuf, unsigned long pgnum)
532 {
533 	struct fastrpc_buf *buf = dmabuf->priv;
534 
535 	return buf->virt ? buf->virt + pgnum * PAGE_SIZE : NULL;
536 }
537 
538 static void *fastrpc_vmap(struct dma_buf *dmabuf)
539 {
540 	struct fastrpc_buf *buf = dmabuf->priv;
541 
542 	return buf->virt;
543 }
544 
545 static int fastrpc_mmap(struct dma_buf *dmabuf,
546 			struct vm_area_struct *vma)
547 {
548 	struct fastrpc_buf *buf = dmabuf->priv;
549 	size_t size = vma->vm_end - vma->vm_start;
550 
551 	return dma_mmap_coherent(buf->dev, vma, buf->virt,
552 				 FASTRPC_PHYS(buf->phys), size);
553 }
554 
555 static const struct dma_buf_ops fastrpc_dma_buf_ops = {
556 	.attach = fastrpc_dma_buf_attach,
557 	.detach = fastrpc_dma_buf_detatch,
558 	.map_dma_buf = fastrpc_map_dma_buf,
559 	.unmap_dma_buf = fastrpc_unmap_dma_buf,
560 	.mmap = fastrpc_mmap,
561 	.map = fastrpc_kmap,
562 	.vmap = fastrpc_vmap,
563 	.release = fastrpc_release,
564 };
565 
566 static int fastrpc_map_create(struct fastrpc_user *fl, int fd,
567 			      u64 len, struct fastrpc_map **ppmap)
568 {
569 	struct fastrpc_session_ctx *sess = fl->sctx;
570 	struct fastrpc_map *map = NULL;
571 	int err = 0;
572 
573 	if (!fastrpc_map_find(fl, fd, ppmap))
574 		return 0;
575 
576 	map = kzalloc(sizeof(*map), GFP_KERNEL);
577 	if (!map)
578 		return -ENOMEM;
579 
580 	INIT_LIST_HEAD(&map->node);
581 	map->fl = fl;
582 	map->fd = fd;
583 	map->buf = dma_buf_get(fd);
584 	if (IS_ERR(map->buf)) {
585 		err = PTR_ERR(map->buf);
586 		goto get_err;
587 	}
588 
589 	map->attach = dma_buf_attach(map->buf, sess->dev);
590 	if (IS_ERR(map->attach)) {
591 		dev_err(sess->dev, "Failed to attach dmabuf\n");
592 		err = PTR_ERR(map->attach);
593 		goto attach_err;
594 	}
595 
596 	map->table = dma_buf_map_attachment(map->attach, DMA_BIDIRECTIONAL);
597 	if (IS_ERR(map->table)) {
598 		err = PTR_ERR(map->table);
599 		goto map_err;
600 	}
601 
602 	map->phys = sg_dma_address(map->table->sgl);
603 	map->phys += ((u64)fl->sctx->sid << 32);
604 	map->size = len;
605 	map->va = sg_virt(map->table->sgl);
606 	map->len = len;
607 	kref_init(&map->refcount);
608 
609 	spin_lock(&fl->lock);
610 	list_add_tail(&map->node, &fl->maps);
611 	spin_unlock(&fl->lock);
612 	*ppmap = map;
613 
614 	return 0;
615 
616 map_err:
617 	dma_buf_detach(map->buf, map->attach);
618 attach_err:
619 	dma_buf_put(map->buf);
620 get_err:
621 	kfree(map);
622 
623 	return err;
624 }
625 
626 /*
627  * Fastrpc payload buffer with metadata looks like:
628  *
629  * >>>>>>  START of METADATA <<<<<<<<<
630  * +---------------------------------+
631  * |           Arguments             |
632  * | type:(struct fastrpc_remote_arg)|
633  * |             (0 - N)             |
634  * +---------------------------------+
635  * |         Invoke Buffer list      |
636  * | type:(struct fastrpc_invoke_buf)|
637  * |           (0 - N)               |
638  * +---------------------------------+
639  * |         Page info list          |
640  * | type:(struct fastrpc_phy_page)  |
641  * |             (0 - N)             |
642  * +---------------------------------+
643  * |         Optional info           |
644  * |(can be specific to SoC/Firmware)|
645  * +---------------------------------+
646  * >>>>>>>>  END of METADATA <<<<<<<<<
647  * +---------------------------------+
648  * |         Inline ARGS             |
649  * |            (0-N)                |
650  * +---------------------------------+
651  */
652 
653 static int fastrpc_get_meta_size(struct fastrpc_invoke_ctx *ctx)
654 {
655 	int size = 0;
656 
657 	size = (sizeof(struct fastrpc_remote_arg) +
658 		sizeof(struct fastrpc_invoke_buf) +
659 		sizeof(struct fastrpc_phy_page)) * ctx->nscalars +
660 		sizeof(u64) * FASTRPC_MAX_FDLIST +
661 		sizeof(u32) * FASTRPC_MAX_CRCLIST;
662 
663 	return size;
664 }
665 
666 static u64 fastrpc_get_payload_size(struct fastrpc_invoke_ctx *ctx, int metalen)
667 {
668 	u64 size = 0;
669 	int i;
670 
671 	size = ALIGN(metalen, FASTRPC_ALIGN);
672 	for (i = 0; i < ctx->nscalars; i++) {
673 		if (ctx->args[i].fd == 0 || ctx->args[i].fd == -1) {
674 
675 			if (ctx->olaps[i].offset == 0)
676 				size = ALIGN(size, FASTRPC_ALIGN);
677 
678 			size += (ctx->olaps[i].mend - ctx->olaps[i].mstart);
679 		}
680 	}
681 
682 	return size;
683 }
684 
685 static int fastrpc_create_maps(struct fastrpc_invoke_ctx *ctx)
686 {
687 	struct device *dev = ctx->fl->sctx->dev;
688 	int i, err;
689 
690 	for (i = 0; i < ctx->nscalars; ++i) {
691 		/* Make sure reserved field is set to 0 */
692 		if (ctx->args[i].reserved)
693 			return -EINVAL;
694 
695 		if (ctx->args[i].fd == 0 || ctx->args[i].fd == -1 ||
696 		    ctx->args[i].length == 0)
697 			continue;
698 
699 		err = fastrpc_map_create(ctx->fl, ctx->args[i].fd,
700 					 ctx->args[i].length, &ctx->maps[i]);
701 		if (err) {
702 			dev_err(dev, "Error Creating map %d\n", err);
703 			return -EINVAL;
704 		}
705 
706 	}
707 	return 0;
708 }
709 
710 static int fastrpc_get_args(u32 kernel, struct fastrpc_invoke_ctx *ctx)
711 {
712 	struct device *dev = ctx->fl->sctx->dev;
713 	struct fastrpc_remote_arg *rpra;
714 	struct fastrpc_invoke_buf *list;
715 	struct fastrpc_phy_page *pages;
716 	int inbufs, i, oix, err = 0;
717 	u64 len, rlen, pkt_size;
718 	u64 pg_start, pg_end;
719 	uintptr_t args;
720 	int metalen;
721 
722 	inbufs = REMOTE_SCALARS_INBUFS(ctx->sc);
723 	metalen = fastrpc_get_meta_size(ctx);
724 	pkt_size = fastrpc_get_payload_size(ctx, metalen);
725 
726 	err = fastrpc_create_maps(ctx);
727 	if (err)
728 		return err;
729 
730 	ctx->msg_sz = pkt_size;
731 
732 	err = fastrpc_buf_alloc(ctx->fl, dev, pkt_size, &ctx->buf);
733 	if (err)
734 		return err;
735 
736 	rpra = ctx->buf->virt;
737 	list = ctx->buf->virt + ctx->nscalars * sizeof(*rpra);
738 	pages = ctx->buf->virt + ctx->nscalars * (sizeof(*list) +
739 		sizeof(*rpra));
740 	args = (uintptr_t)ctx->buf->virt + metalen;
741 	rlen = pkt_size - metalen;
742 	ctx->rpra = rpra;
743 
744 	for (oix = 0; oix < ctx->nbufs; ++oix) {
745 		int mlen;
746 
747 		i = ctx->olaps[oix].raix;
748 		len = ctx->args[i].length;
749 
750 		rpra[i].pv = 0;
751 		rpra[i].len = len;
752 		list[i].num = len ? 1 : 0;
753 		list[i].pgidx = i;
754 
755 		if (!len)
756 			continue;
757 
758 		if (ctx->maps[i]) {
759 			struct vm_area_struct *vma = NULL;
760 
761 			rpra[i].pv = (u64) ctx->args[i].ptr;
762 			pages[i].addr = ctx->maps[i]->phys;
763 
764 			vma = find_vma(current->mm, ctx->args[i].ptr);
765 			if (vma)
766 				pages[i].addr += ctx->args[i].ptr -
767 						 vma->vm_start;
768 
769 			pg_start = (ctx->args[i].ptr & PAGE_MASK) >> PAGE_SHIFT;
770 			pg_end = ((ctx->args[i].ptr + len - 1) & PAGE_MASK) >>
771 				  PAGE_SHIFT;
772 			pages[i].size = (pg_end - pg_start + 1) * PAGE_SIZE;
773 
774 		} else {
775 
776 			if (ctx->olaps[oix].offset == 0) {
777 				rlen -= ALIGN(args, FASTRPC_ALIGN) - args;
778 				args = ALIGN(args, FASTRPC_ALIGN);
779 			}
780 
781 			mlen = ctx->olaps[oix].mend - ctx->olaps[oix].mstart;
782 
783 			if (rlen < mlen)
784 				goto bail;
785 
786 			rpra[i].pv = args - ctx->olaps[oix].offset;
787 			pages[i].addr = ctx->buf->phys -
788 					ctx->olaps[oix].offset +
789 					(pkt_size - rlen);
790 			pages[i].addr = pages[i].addr &	PAGE_MASK;
791 
792 			pg_start = (args & PAGE_MASK) >> PAGE_SHIFT;
793 			pg_end = ((args + len - 1) & PAGE_MASK) >> PAGE_SHIFT;
794 			pages[i].size = (pg_end - pg_start + 1) * PAGE_SIZE;
795 			args = args + mlen;
796 			rlen -= mlen;
797 		}
798 
799 		if (i < inbufs && !ctx->maps[i]) {
800 			void *dst = (void *)(uintptr_t)rpra[i].pv;
801 			void *src = (void *)(uintptr_t)ctx->args[i].ptr;
802 
803 			if (!kernel) {
804 				if (copy_from_user(dst, (void __user *)src,
805 						   len)) {
806 					err = -EFAULT;
807 					goto bail;
808 				}
809 			} else {
810 				memcpy(dst, src, len);
811 			}
812 		}
813 	}
814 
815 	for (i = ctx->nbufs; i < ctx->nscalars; ++i) {
816 		rpra[i].pv = (u64) ctx->args[i].ptr;
817 		rpra[i].len = ctx->args[i].length;
818 		list[i].num = ctx->args[i].length ? 1 : 0;
819 		list[i].pgidx = i;
820 		pages[i].addr = ctx->maps[i]->phys;
821 		pages[i].size = ctx->maps[i]->size;
822 	}
823 
824 bail:
825 	if (err)
826 		dev_err(dev, "Error: get invoke args failed:%d\n", err);
827 
828 	return err;
829 }
830 
831 static int fastrpc_put_args(struct fastrpc_invoke_ctx *ctx,
832 			    u32 kernel)
833 {
834 	struct fastrpc_remote_arg *rpra = ctx->rpra;
835 	int i, inbufs;
836 
837 	inbufs = REMOTE_SCALARS_INBUFS(ctx->sc);
838 
839 	for (i = inbufs; i < ctx->nbufs; ++i) {
840 		void *src = (void *)(uintptr_t)rpra[i].pv;
841 		void *dst = (void *)(uintptr_t)ctx->args[i].ptr;
842 		u64 len = rpra[i].len;
843 
844 		if (!kernel) {
845 			if (copy_to_user((void __user *)dst, src, len))
846 				return -EFAULT;
847 		} else {
848 			memcpy(dst, src, len);
849 		}
850 	}
851 
852 	return 0;
853 }
854 
855 static int fastrpc_invoke_send(struct fastrpc_session_ctx *sctx,
856 			       struct fastrpc_invoke_ctx *ctx,
857 			       u32 kernel, uint32_t handle)
858 {
859 	struct fastrpc_channel_ctx *cctx;
860 	struct fastrpc_user *fl = ctx->fl;
861 	struct fastrpc_msg *msg = &ctx->msg;
862 
863 	cctx = fl->cctx;
864 	msg->pid = fl->tgid;
865 	msg->tid = current->pid;
866 
867 	if (kernel)
868 		msg->pid = 0;
869 
870 	msg->ctx = ctx->ctxid | fl->pd;
871 	msg->handle = handle;
872 	msg->sc = ctx->sc;
873 	msg->addr = ctx->buf ? ctx->buf->phys : 0;
874 	msg->size = roundup(ctx->msg_sz, PAGE_SIZE);
875 	fastrpc_context_get(ctx);
876 
877 	return rpmsg_send(cctx->rpdev->ept, (void *)msg, sizeof(*msg));
878 }
879 
880 static int fastrpc_internal_invoke(struct fastrpc_user *fl,  u32 kernel,
881 				   u32 handle, u32 sc,
882 				   struct fastrpc_invoke_args *args)
883 {
884 	struct fastrpc_invoke_ctx *ctx = NULL;
885 	int err = 0;
886 
887 	if (!fl->sctx)
888 		return -EINVAL;
889 
890 	ctx = fastrpc_context_alloc(fl, kernel, sc, args);
891 	if (IS_ERR(ctx))
892 		return PTR_ERR(ctx);
893 
894 	if (ctx->nscalars) {
895 		err = fastrpc_get_args(kernel, ctx);
896 		if (err)
897 			goto bail;
898 	}
899 
900 	/* make sure that all CPU memory writes are seen by DSP */
901 	dma_wmb();
902 	/* Send invoke buffer to remote dsp */
903 	err = fastrpc_invoke_send(fl->sctx, ctx, kernel, handle);
904 	if (err)
905 		goto bail;
906 
907 	/* Wait for remote dsp to respond or time out */
908 	err = wait_for_completion_interruptible(&ctx->work);
909 	if (err)
910 		goto bail;
911 
912 	/* Check the response from remote dsp */
913 	err = ctx->retval;
914 	if (err)
915 		goto bail;
916 
917 	if (ctx->nscalars) {
918 		/* make sure that all memory writes by DSP are seen by CPU */
919 		dma_rmb();
920 		/* populate all the output buffers with results */
921 		err = fastrpc_put_args(ctx, kernel);
922 		if (err)
923 			goto bail;
924 	}
925 
926 bail:
927 	/* We are done with this compute context, remove it from pending list */
928 	spin_lock(&fl->lock);
929 	list_del(&ctx->node);
930 	spin_unlock(&fl->lock);
931 	fastrpc_context_put(ctx);
932 
933 	if (err)
934 		dev_dbg(fl->sctx->dev, "Error: Invoke Failed %d\n", err);
935 
936 	return err;
937 }
938 
939 static int fastrpc_init_create_process(struct fastrpc_user *fl,
940 					char __user *argp)
941 {
942 	struct fastrpc_init_create init;
943 	struct fastrpc_invoke_args *args;
944 	struct fastrpc_phy_page pages[1];
945 	struct fastrpc_map *map = NULL;
946 	struct fastrpc_buf *imem = NULL;
947 	int memlen;
948 	int err;
949 	struct {
950 		int pgid;
951 		u32 namelen;
952 		u32 filelen;
953 		u32 pageslen;
954 		u32 attrs;
955 		u32 siglen;
956 	} inbuf;
957 	u32 sc;
958 
959 	args = kcalloc(FASTRPC_CREATE_PROCESS_NARGS, sizeof(*args), GFP_KERNEL);
960 	if (!args)
961 		return -ENOMEM;
962 
963 	if (copy_from_user(&init, argp, sizeof(init))) {
964 		err = -EFAULT;
965 		goto err;
966 	}
967 
968 	if (init.filelen > INIT_FILELEN_MAX) {
969 		err = -EINVAL;
970 		goto err;
971 	}
972 
973 	inbuf.pgid = fl->tgid;
974 	inbuf.namelen = strlen(current->comm) + 1;
975 	inbuf.filelen = init.filelen;
976 	inbuf.pageslen = 1;
977 	inbuf.attrs = init.attrs;
978 	inbuf.siglen = init.siglen;
979 	fl->pd = 1;
980 
981 	if (init.filelen && init.filefd) {
982 		err = fastrpc_map_create(fl, init.filefd, init.filelen, &map);
983 		if (err)
984 			goto err;
985 	}
986 
987 	memlen = ALIGN(max(INIT_FILELEN_MAX, (int)init.filelen * 4),
988 		       1024 * 1024);
989 	err = fastrpc_buf_alloc(fl, fl->sctx->dev, memlen,
990 				&imem);
991 	if (err)
992 		goto err_alloc;
993 
994 	fl->init_mem = imem;
995 	args[0].ptr = (u64)(uintptr_t)&inbuf;
996 	args[0].length = sizeof(inbuf);
997 	args[0].fd = -1;
998 
999 	args[1].ptr = (u64)(uintptr_t)current->comm;
1000 	args[1].length = inbuf.namelen;
1001 	args[1].fd = -1;
1002 
1003 	args[2].ptr = (u64) init.file;
1004 	args[2].length = inbuf.filelen;
1005 	args[2].fd = init.filefd;
1006 
1007 	pages[0].addr = imem->phys;
1008 	pages[0].size = imem->size;
1009 
1010 	args[3].ptr = (u64)(uintptr_t) pages;
1011 	args[3].length = 1 * sizeof(*pages);
1012 	args[3].fd = -1;
1013 
1014 	args[4].ptr = (u64)(uintptr_t)&inbuf.attrs;
1015 	args[4].length = sizeof(inbuf.attrs);
1016 	args[4].fd = -1;
1017 
1018 	args[5].ptr = (u64)(uintptr_t) &inbuf.siglen;
1019 	args[5].length = sizeof(inbuf.siglen);
1020 	args[5].fd = -1;
1021 
1022 	sc = FASTRPC_SCALARS(FASTRPC_RMID_INIT_CREATE, 4, 0);
1023 	if (init.attrs)
1024 		sc = FASTRPC_SCALARS(FASTRPC_RMID_INIT_CREATE_ATTR, 6, 0);
1025 
1026 	err = fastrpc_internal_invoke(fl, true, FASTRPC_INIT_HANDLE,
1027 				      sc, args);
1028 	if (err)
1029 		goto err_invoke;
1030 
1031 	kfree(args);
1032 
1033 	return 0;
1034 
1035 err_invoke:
1036 	fl->init_mem = NULL;
1037 	fastrpc_buf_free(imem);
1038 err_alloc:
1039 	if (map) {
1040 		spin_lock(&fl->lock);
1041 		list_del(&map->node);
1042 		spin_unlock(&fl->lock);
1043 		fastrpc_map_put(map);
1044 	}
1045 err:
1046 	kfree(args);
1047 
1048 	return err;
1049 }
1050 
1051 static struct fastrpc_session_ctx *fastrpc_session_alloc(
1052 					struct fastrpc_channel_ctx *cctx)
1053 {
1054 	struct fastrpc_session_ctx *session = NULL;
1055 	unsigned long flags;
1056 	int i;
1057 
1058 	spin_lock_irqsave(&cctx->lock, flags);
1059 	for (i = 0; i < cctx->sesscount; i++) {
1060 		if (!cctx->session[i].used && cctx->session[i].valid) {
1061 			cctx->session[i].used = true;
1062 			session = &cctx->session[i];
1063 			break;
1064 		}
1065 	}
1066 	spin_unlock_irqrestore(&cctx->lock, flags);
1067 
1068 	return session;
1069 }
1070 
1071 static void fastrpc_session_free(struct fastrpc_channel_ctx *cctx,
1072 				 struct fastrpc_session_ctx *session)
1073 {
1074 	unsigned long flags;
1075 
1076 	spin_lock_irqsave(&cctx->lock, flags);
1077 	session->used = false;
1078 	spin_unlock_irqrestore(&cctx->lock, flags);
1079 }
1080 
1081 static int fastrpc_release_current_dsp_process(struct fastrpc_user *fl)
1082 {
1083 	struct fastrpc_invoke_args args[1];
1084 	int tgid = 0;
1085 	u32 sc;
1086 
1087 	tgid = fl->tgid;
1088 	args[0].ptr = (u64)(uintptr_t) &tgid;
1089 	args[0].length = sizeof(tgid);
1090 	args[0].fd = -1;
1091 	args[0].reserved = 0;
1092 	sc = FASTRPC_SCALARS(FASTRPC_RMID_INIT_RELEASE, 1, 0);
1093 
1094 	return fastrpc_internal_invoke(fl, true, FASTRPC_INIT_HANDLE,
1095 				       sc, &args[0]);
1096 }
1097 
1098 static int fastrpc_device_release(struct inode *inode, struct file *file)
1099 {
1100 	struct fastrpc_user *fl = (struct fastrpc_user *)file->private_data;
1101 	struct fastrpc_channel_ctx *cctx = fl->cctx;
1102 	struct fastrpc_invoke_ctx *ctx, *n;
1103 	struct fastrpc_map *map, *m;
1104 	unsigned long flags;
1105 
1106 	fastrpc_release_current_dsp_process(fl);
1107 
1108 	spin_lock_irqsave(&cctx->lock, flags);
1109 	list_del(&fl->user);
1110 	spin_unlock_irqrestore(&cctx->lock, flags);
1111 
1112 	if (fl->init_mem)
1113 		fastrpc_buf_free(fl->init_mem);
1114 
1115 	list_for_each_entry_safe(ctx, n, &fl->pending, node) {
1116 		list_del(&ctx->node);
1117 		fastrpc_context_put(ctx);
1118 	}
1119 
1120 	list_for_each_entry_safe(map, m, &fl->maps, node) {
1121 		list_del(&map->node);
1122 		fastrpc_map_put(map);
1123 	}
1124 
1125 	fastrpc_session_free(cctx, fl->sctx);
1126 
1127 	mutex_destroy(&fl->mutex);
1128 	kfree(fl);
1129 	file->private_data = NULL;
1130 
1131 	return 0;
1132 }
1133 
1134 static int fastrpc_device_open(struct inode *inode, struct file *filp)
1135 {
1136 	struct fastrpc_channel_ctx *cctx = miscdev_to_cctx(filp->private_data);
1137 	struct fastrpc_user *fl = NULL;
1138 	unsigned long flags;
1139 
1140 	fl = kzalloc(sizeof(*fl), GFP_KERNEL);
1141 	if (!fl)
1142 		return -ENOMEM;
1143 
1144 	filp->private_data = fl;
1145 	spin_lock_init(&fl->lock);
1146 	mutex_init(&fl->mutex);
1147 	INIT_LIST_HEAD(&fl->pending);
1148 	INIT_LIST_HEAD(&fl->maps);
1149 	INIT_LIST_HEAD(&fl->user);
1150 	fl->tgid = current->tgid;
1151 	fl->cctx = cctx;
1152 
1153 	fl->sctx = fastrpc_session_alloc(cctx);
1154 	if (!fl->sctx) {
1155 		dev_err(&cctx->rpdev->dev, "No session available\n");
1156 		mutex_destroy(&fl->mutex);
1157 		kfree(fl);
1158 
1159 		return -EBUSY;
1160 	}
1161 
1162 	spin_lock_irqsave(&cctx->lock, flags);
1163 	list_add_tail(&fl->user, &cctx->users);
1164 	spin_unlock_irqrestore(&cctx->lock, flags);
1165 
1166 	return 0;
1167 }
1168 
1169 static int fastrpc_dmabuf_free(struct fastrpc_user *fl, char __user *argp)
1170 {
1171 	struct dma_buf *buf;
1172 	int info;
1173 
1174 	if (copy_from_user(&info, argp, sizeof(info)))
1175 		return -EFAULT;
1176 
1177 	buf = dma_buf_get(info);
1178 	if (IS_ERR_OR_NULL(buf))
1179 		return -EINVAL;
1180 	/*
1181 	 * one for the last get and other for the ALLOC_DMA_BUFF ioctl
1182 	 */
1183 	dma_buf_put(buf);
1184 	dma_buf_put(buf);
1185 
1186 	return 0;
1187 }
1188 
1189 static int fastrpc_dmabuf_alloc(struct fastrpc_user *fl, char __user *argp)
1190 {
1191 	struct fastrpc_alloc_dma_buf bp;
1192 	DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
1193 	struct fastrpc_buf *buf = NULL;
1194 	int err;
1195 
1196 	if (copy_from_user(&bp, argp, sizeof(bp)))
1197 		return -EFAULT;
1198 
1199 	err = fastrpc_buf_alloc(fl, fl->sctx->dev, bp.size, &buf);
1200 	if (err)
1201 		return err;
1202 	exp_info.ops = &fastrpc_dma_buf_ops;
1203 	exp_info.size = bp.size;
1204 	exp_info.flags = O_RDWR;
1205 	exp_info.priv = buf;
1206 	buf->dmabuf = dma_buf_export(&exp_info);
1207 	if (IS_ERR(buf->dmabuf)) {
1208 		err = PTR_ERR(buf->dmabuf);
1209 		fastrpc_buf_free(buf);
1210 		return err;
1211 	}
1212 
1213 	bp.fd = dma_buf_fd(buf->dmabuf, O_ACCMODE);
1214 	if (bp.fd < 0) {
1215 		dma_buf_put(buf->dmabuf);
1216 		return -EINVAL;
1217 	}
1218 
1219 	if (copy_to_user(argp, &bp, sizeof(bp))) {
1220 		dma_buf_put(buf->dmabuf);
1221 		return -EFAULT;
1222 	}
1223 
1224 	get_dma_buf(buf->dmabuf);
1225 
1226 	return 0;
1227 }
1228 
1229 static int fastrpc_init_attach(struct fastrpc_user *fl)
1230 {
1231 	struct fastrpc_invoke_args args[1];
1232 	int tgid = fl->tgid;
1233 	u32 sc;
1234 
1235 	args[0].ptr = (u64)(uintptr_t) &tgid;
1236 	args[0].length = sizeof(tgid);
1237 	args[0].fd = -1;
1238 	args[0].reserved = 0;
1239 	sc = FASTRPC_SCALARS(FASTRPC_RMID_INIT_ATTACH, 1, 0);
1240 	fl->pd = 0;
1241 
1242 	return fastrpc_internal_invoke(fl, true, FASTRPC_INIT_HANDLE,
1243 				       sc, &args[0]);
1244 }
1245 
1246 static int fastrpc_invoke(struct fastrpc_user *fl, char __user *argp)
1247 {
1248 	struct fastrpc_invoke_args *args = NULL;
1249 	struct fastrpc_invoke inv;
1250 	u32 nscalars;
1251 	int err;
1252 
1253 	if (copy_from_user(&inv, argp, sizeof(inv)))
1254 		return -EFAULT;
1255 
1256 	/* nscalars is truncated here to max supported value */
1257 	nscalars = REMOTE_SCALARS_LENGTH(inv.sc);
1258 	if (nscalars) {
1259 		args = kcalloc(nscalars, sizeof(*args), GFP_KERNEL);
1260 		if (!args)
1261 			return -ENOMEM;
1262 
1263 		if (copy_from_user(args, (void __user *)(uintptr_t)inv.args,
1264 				   nscalars * sizeof(*args))) {
1265 			kfree(args);
1266 			return -EFAULT;
1267 		}
1268 	}
1269 
1270 	err = fastrpc_internal_invoke(fl, false, inv.handle, inv.sc, args);
1271 	kfree(args);
1272 
1273 	return err;
1274 }
1275 
1276 static long fastrpc_device_ioctl(struct file *file, unsigned int cmd,
1277 				 unsigned long arg)
1278 {
1279 	struct fastrpc_user *fl = (struct fastrpc_user *)file->private_data;
1280 	char __user *argp = (char __user *)arg;
1281 	int err;
1282 
1283 	switch (cmd) {
1284 	case FASTRPC_IOCTL_INVOKE:
1285 		err = fastrpc_invoke(fl, argp);
1286 		break;
1287 	case FASTRPC_IOCTL_INIT_ATTACH:
1288 		err = fastrpc_init_attach(fl);
1289 		break;
1290 	case FASTRPC_IOCTL_INIT_CREATE:
1291 		err = fastrpc_init_create_process(fl, argp);
1292 		break;
1293 	case FASTRPC_IOCTL_FREE_DMA_BUFF:
1294 		err = fastrpc_dmabuf_free(fl, argp);
1295 		break;
1296 	case FASTRPC_IOCTL_ALLOC_DMA_BUFF:
1297 		err = fastrpc_dmabuf_alloc(fl, argp);
1298 		break;
1299 	default:
1300 		err = -ENOTTY;
1301 		break;
1302 	}
1303 
1304 	return err;
1305 }
1306 
1307 static const struct file_operations fastrpc_fops = {
1308 	.open = fastrpc_device_open,
1309 	.release = fastrpc_device_release,
1310 	.unlocked_ioctl = fastrpc_device_ioctl,
1311 	.compat_ioctl = fastrpc_device_ioctl,
1312 };
1313 
1314 static int fastrpc_cb_probe(struct platform_device *pdev)
1315 {
1316 	struct fastrpc_channel_ctx *cctx;
1317 	struct fastrpc_session_ctx *sess;
1318 	struct device *dev = &pdev->dev;
1319 	int i, sessions = 0;
1320 	unsigned long flags;
1321 	int rc;
1322 
1323 	cctx = dev_get_drvdata(dev->parent);
1324 	if (!cctx)
1325 		return -EINVAL;
1326 
1327 	of_property_read_u32(dev->of_node, "qcom,nsessions", &sessions);
1328 
1329 	spin_lock_irqsave(&cctx->lock, flags);
1330 	sess = &cctx->session[cctx->sesscount];
1331 	sess->used = false;
1332 	sess->valid = true;
1333 	sess->dev = dev;
1334 	dev_set_drvdata(dev, sess);
1335 
1336 	if (of_property_read_u32(dev->of_node, "reg", &sess->sid))
1337 		dev_info(dev, "FastRPC Session ID not specified in DT\n");
1338 
1339 	if (sessions > 0) {
1340 		struct fastrpc_session_ctx *dup_sess;
1341 
1342 		for (i = 1; i < sessions; i++) {
1343 			if (cctx->sesscount++ >= FASTRPC_MAX_SESSIONS)
1344 				break;
1345 			dup_sess = &cctx->session[cctx->sesscount];
1346 			memcpy(dup_sess, sess, sizeof(*dup_sess));
1347 		}
1348 	}
1349 	cctx->sesscount++;
1350 	spin_unlock_irqrestore(&cctx->lock, flags);
1351 	rc = dma_set_mask(dev, DMA_BIT_MASK(32));
1352 	if (rc) {
1353 		dev_err(dev, "32-bit DMA enable failed\n");
1354 		return rc;
1355 	}
1356 
1357 	return 0;
1358 }
1359 
1360 static int fastrpc_cb_remove(struct platform_device *pdev)
1361 {
1362 	struct fastrpc_channel_ctx *cctx = dev_get_drvdata(pdev->dev.parent);
1363 	struct fastrpc_session_ctx *sess = dev_get_drvdata(&pdev->dev);
1364 	unsigned long flags;
1365 	int i;
1366 
1367 	spin_lock_irqsave(&cctx->lock, flags);
1368 	for (i = 1; i < FASTRPC_MAX_SESSIONS; i++) {
1369 		if (cctx->session[i].sid == sess->sid) {
1370 			cctx->session[i].valid = false;
1371 			cctx->sesscount--;
1372 		}
1373 	}
1374 	spin_unlock_irqrestore(&cctx->lock, flags);
1375 
1376 	return 0;
1377 }
1378 
1379 static const struct of_device_id fastrpc_match_table[] = {
1380 	{ .compatible = "qcom,fastrpc-compute-cb", },
1381 	{}
1382 };
1383 
1384 static struct platform_driver fastrpc_cb_driver = {
1385 	.probe = fastrpc_cb_probe,
1386 	.remove = fastrpc_cb_remove,
1387 	.driver = {
1388 		.name = "qcom,fastrpc-cb",
1389 		.of_match_table = fastrpc_match_table,
1390 		.suppress_bind_attrs = true,
1391 	},
1392 };
1393 
1394 static int fastrpc_rpmsg_probe(struct rpmsg_device *rpdev)
1395 {
1396 	struct device *rdev = &rpdev->dev;
1397 	struct fastrpc_channel_ctx *data;
1398 	int i, err, domain_id = -1;
1399 	const char *domain;
1400 
1401 	data = devm_kzalloc(rdev, sizeof(*data), GFP_KERNEL);
1402 	if (!data)
1403 		return -ENOMEM;
1404 
1405 	err = of_property_read_string(rdev->of_node, "label", &domain);
1406 	if (err) {
1407 		dev_info(rdev, "FastRPC Domain not specified in DT\n");
1408 		return err;
1409 	}
1410 
1411 	for (i = 0; i <= CDSP_DOMAIN_ID; i++) {
1412 		if (!strcmp(domains[i], domain)) {
1413 			domain_id = i;
1414 			break;
1415 		}
1416 	}
1417 
1418 	if (domain_id < 0) {
1419 		dev_info(rdev, "FastRPC Invalid Domain ID %d\n", domain_id);
1420 		return -EINVAL;
1421 	}
1422 
1423 	data->miscdev.minor = MISC_DYNAMIC_MINOR;
1424 	data->miscdev.name = kasprintf(GFP_KERNEL, "fastrpc-%s",
1425 				domains[domain_id]);
1426 	data->miscdev.fops = &fastrpc_fops;
1427 	err = misc_register(&data->miscdev);
1428 	if (err)
1429 		return err;
1430 
1431 	dev_set_drvdata(&rpdev->dev, data);
1432 	dma_set_mask_and_coherent(rdev, DMA_BIT_MASK(32));
1433 	INIT_LIST_HEAD(&data->users);
1434 	spin_lock_init(&data->lock);
1435 	idr_init(&data->ctx_idr);
1436 	data->domain_id = domain_id;
1437 	data->rpdev = rpdev;
1438 
1439 	return of_platform_populate(rdev->of_node, NULL, NULL, rdev);
1440 }
1441 
1442 static void fastrpc_notify_users(struct fastrpc_user *user)
1443 {
1444 	struct fastrpc_invoke_ctx *ctx;
1445 
1446 	spin_lock(&user->lock);
1447 	list_for_each_entry(ctx, &user->pending, node)
1448 		complete(&ctx->work);
1449 	spin_unlock(&user->lock);
1450 }
1451 
1452 static void fastrpc_rpmsg_remove(struct rpmsg_device *rpdev)
1453 {
1454 	struct fastrpc_channel_ctx *cctx = dev_get_drvdata(&rpdev->dev);
1455 	struct fastrpc_user *user;
1456 	unsigned long flags;
1457 
1458 	spin_lock_irqsave(&cctx->lock, flags);
1459 	list_for_each_entry(user, &cctx->users, user)
1460 		fastrpc_notify_users(user);
1461 	spin_unlock_irqrestore(&cctx->lock, flags);
1462 
1463 	misc_deregister(&cctx->miscdev);
1464 	of_platform_depopulate(&rpdev->dev);
1465 	kfree(cctx);
1466 }
1467 
1468 static int fastrpc_rpmsg_callback(struct rpmsg_device *rpdev, void *data,
1469 				  int len, void *priv, u32 addr)
1470 {
1471 	struct fastrpc_channel_ctx *cctx = dev_get_drvdata(&rpdev->dev);
1472 	struct fastrpc_invoke_rsp *rsp = data;
1473 	struct fastrpc_invoke_ctx *ctx;
1474 	unsigned long flags;
1475 	unsigned long ctxid;
1476 
1477 	if (len < sizeof(*rsp))
1478 		return -EINVAL;
1479 
1480 	ctxid = ((rsp->ctx & FASTRPC_CTXID_MASK) >> 4);
1481 
1482 	spin_lock_irqsave(&cctx->lock, flags);
1483 	ctx = idr_find(&cctx->ctx_idr, ctxid);
1484 	spin_unlock_irqrestore(&cctx->lock, flags);
1485 
1486 	if (!ctx) {
1487 		dev_err(&rpdev->dev, "No context ID matches response\n");
1488 		return -ENOENT;
1489 	}
1490 
1491 	ctx->retval = rsp->retval;
1492 	complete(&ctx->work);
1493 
1494 	/*
1495 	 * The DMA buffer associated with the context cannot be freed in
1496 	 * interrupt context so schedule it through a worker thread to
1497 	 * avoid a kernel BUG.
1498 	 */
1499 	schedule_work(&ctx->put_work);
1500 
1501 	return 0;
1502 }
1503 
1504 static const struct of_device_id fastrpc_rpmsg_of_match[] = {
1505 	{ .compatible = "qcom,fastrpc" },
1506 	{ },
1507 };
1508 MODULE_DEVICE_TABLE(of, fastrpc_rpmsg_of_match);
1509 
1510 static struct rpmsg_driver fastrpc_driver = {
1511 	.probe = fastrpc_rpmsg_probe,
1512 	.remove = fastrpc_rpmsg_remove,
1513 	.callback = fastrpc_rpmsg_callback,
1514 	.drv = {
1515 		.name = "qcom,fastrpc",
1516 		.of_match_table = fastrpc_rpmsg_of_match,
1517 	},
1518 };
1519 
1520 static int fastrpc_init(void)
1521 {
1522 	int ret;
1523 
1524 	ret = platform_driver_register(&fastrpc_cb_driver);
1525 	if (ret < 0) {
1526 		pr_err("fastrpc: failed to register cb driver\n");
1527 		return ret;
1528 	}
1529 
1530 	ret = register_rpmsg_driver(&fastrpc_driver);
1531 	if (ret < 0) {
1532 		pr_err("fastrpc: failed to register rpmsg driver\n");
1533 		platform_driver_unregister(&fastrpc_cb_driver);
1534 		return ret;
1535 	}
1536 
1537 	return 0;
1538 }
1539 module_init(fastrpc_init);
1540 
1541 static void fastrpc_exit(void)
1542 {
1543 	platform_driver_unregister(&fastrpc_cb_driver);
1544 	unregister_rpmsg_driver(&fastrpc_driver);
1545 }
1546 module_exit(fastrpc_exit);
1547 
1548 MODULE_LICENSE("GPL v2");
1549