summaryrefslogtreecommitdiffstats
path: root/drivers/tee/tee_shm.c
blob: df4a1553b78b1ab5123640387ab5eab526bb87a4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
/*
 * Copyright (c) 2015-2016, Linaro Limited
 *
 * This software is licensed under the terms of the GNU General Public
 * License version 2, as published by the Free Software Foundation, and
 * may be copied, distributed, and modified under those terms.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 */
#include <linux/device.h>
#include <linux/dma-buf.h>
#include <linux/fdtable.h>
#include <linux/idr.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/tee_drv.h>
#include "tee_private.h"

static void tee_shm_release(struct tee_shm *shm)
{
	struct tee_device *teedev = shm->teedev;

	mutex_lock(&teedev->mutex);
	idr_remove(&teedev->idr, shm->id);
	if (shm->ctx)
		list_del(&shm->link);
	mutex_unlock(&teedev->mutex);

	if (shm->flags & TEE_SHM_POOL) {
		struct tee_shm_pool_mgr *poolm;

		if (shm->flags & TEE_SHM_DMA_BUF)
			poolm = teedev->pool->dma_buf_mgr;
		else
			poolm = teedev->pool->private_mgr;

		poolm->ops->free(poolm, shm);
	} else if (shm->flags & TEE_SHM_REGISTER) {
		size_t n;
		int rc = teedev->desc->ops->shm_unregister(shm->ctx, shm);

		if (rc)
			dev_err(teedev->dev.parent,
				"unregister shm %p failed: %d", shm, rc);

		for (n = 0; n < shm->num_pages; n++)
			put_page(shm->pages[n]);

		kfree(shm->pages);
	}

	if (shm->ctx)
		teedev_ctx_put(shm->ctx);

	kfree(shm);

	tee_device_put(teedev);
}

static struct sg_table *tee_shm_op_map_dma_buf(struct dma_buf_attachment
			*attach, enum dma_data_direction dir)
{
	return NULL;
}

static void tee_shm_op_unmap_dma_buf(struct dma_buf_attachment *attach,
				     struct sg_table *table,
				     enum dma_data_direction dir)
{
}

static void tee_shm_op_release(struct dma_buf *dmabuf)
{
	struct tee_shm *shm = dmabuf->priv;

	tee_shm_release(shm);
}

static void *tee_shm_op_map(struct dma_buf *dmabuf, unsigned long pgnum)
{
	return NULL;
}

static int tee_shm_op_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma)
{
	struct tee_shm *shm = dmabuf->priv;
	size_t size = vma->vm_end - vma->vm_start;

	/* Refuse sharing shared memory provided by application */
	if (shm->flags & TEE_SHM_REGISTER)
		return -EINVAL;

	return remap_pfn_range(vma, vma->vm_start, shm->paddr >> PAGE_SHIFT,
			       size, vma->vm_page_prot);
}

static const struct dma_buf_ops tee_shm_dma_buf_ops = {
	.map_dma_buf = tee_shm_op_map_dma_buf,
	.unmap_dma_buf = tee_shm_op_unmap_dma_buf,
	.release = tee_shm_op_release,
	.map = tee_shm_op_map,
	.mmap = tee_shm_op_mmap,
};

static struct tee_shm *__tee_shm_alloc(struct tee_context *ctx,
				       struct tee_device *teedev,
				       size_t size, u32 flags)
{
	struct tee_shm_pool_mgr *poolm = NULL;
	struct tee_shm *shm;
	void *ret;
	int rc;

	if (ctx && ctx->teedev != teedev) {
		dev_err(teedev->dev.parent, "ctx and teedev mismatch\n");
		return ERR_PTR(-EINVAL);
	}

	if (!(flags & TEE_SHM_MAPPED)) {
		dev_err(teedev->dev.parent,
			"only mapped allocations supported\n");
		return ERR_PTR(-EINVAL);
	}

	if ((flags & ~(TEE_SHM_MAPPED | TEE_SHM_DMA_BUF))) {
		dev_err(teedev->dev.parent, "invalid shm flags 0x%x", flags);
		return ERR_PTR(-EINVAL);
	}

	if (!tee_device_get(teedev))
		return ERR_PTR(-EINVAL);

	if (!teedev->pool) {
		/* teedev has been detached from driver */
		ret = ERR_PTR(-EINVAL);
		goto err_dev_put;
	}

	shm = kzalloc(sizeof(*shm), GFP_KERNEL);
	if (!shm) {
		ret = ERR_PTR(-ENOMEM);
		goto err_dev_put;
	}

	shm->flags = flags | TEE_SHM_POOL;
	shm->teedev = teedev;
	shm->ctx = ctx;
	if (flags & TEE_SHM_DMA_BUF)
		poolm = teedev->pool->dma_buf_mgr;
	else
		poolm = teedev->pool->private_mgr;

	rc = poolm->ops->alloc(poolm, shm, size);
	if (rc) {
		ret = ERR_PTR(rc);
		goto err_kfree;
	}

	mutex_lock(&teedev->mutex);
	shm->id = idr_alloc(&teedev->idr, shm, 1, 0, GFP_KERNEL);
	mutex_unlock(&teedev->mutex);
	if (shm->id < 0) {
		ret = ERR_PTR(shm->id);
		goto err_pool_free;
	}

	if (flags & TEE_SHM_DMA_BUF) {
		DEFINE_DMA_BUF_EXPORT_INFO(exp_info);

		exp_info.ops = &tee_shm_dma_buf_ops;
		exp_info.size = shm->size;
		exp_info.flags = O_RDWR;
		exp_info.priv = shm;

		shm->dmabuf = dma_buf_export(&exp_info);
		if (IS_ERR(shm->dmabuf)) {
			ret = ERR_CAST(shm->dmabuf);
			goto err_rem;
		}
	}

	if (ctx) {
		teedev_ctx_get(ctx);
		mutex_lock(&teedev->mutex);
		list_add_tail(&shm->link, &ctx->list_shm);
		mutex_unlock(&teedev->mutex);
	}

	return shm;
err_rem:
	mutex_lock(&teedev->mutex);
	idr_remove(&teedev->idr, shm->id);
	mutex_unlock(&teedev->mutex);
err_pool_free:
	poolm->ops->free(poolm, shm);
err_kfree:
	kfree(shm);
err_dev_put:
	tee_device_put(teedev);
	return ret;
}

/**
 * tee_shm_alloc() - Allocate shared memory
 * @ctx:	Context that allocates the shared memory
 * @size:	Requested size of shared memory
 * @flags:	Flags setting properties for the requested shared memory.
 *
 * Memory allocated as global shared memory is automatically freed when the
 * TEE file pointer is closed. The @flags field uses the bits defined by
 * TEE_SHM_* in <linux/tee_drv.h>. TEE_SHM_MAPPED must currently always be
 * set. If TEE_SHM_DMA_BUF global shared memory will be allocated and
 * associated with a dma-buf handle, else driver private memory.
 */
struct tee_shm *tee_shm_alloc(struct tee_context *ctx, size_t size, u32 flags)
{
	return __tee_shm_alloc(ctx, ctx->teedev, size, flags);
}
EXPORT_SYMBOL_GPL(tee_shm_alloc);

struct tee_shm *tee_shm_priv_alloc(struct tee_device *teedev, size_t size)
{
	return __tee_shm_alloc(NULL, teedev, size, TEE_SHM_MAPPED);
}
EXPORT_SYMBOL_GPL(tee_shm_priv_alloc);

struct tee_shm *tee_shm_register(struct tee_context *ctx, unsigned long addr,
				 size_t length, u32 flags)
{
	struct tee_device *teedev = ctx->teedev;
	const u32 req_flags = TEE_SHM_DMA_BUF | TEE_SHM_USER_MAPPED;
	struct tee_shm *shm;
	void *ret;
	int rc;
	int num_pages;
	unsigned long start;

	if (flags != req_flags)
		return ERR_PTR(-ENOTSUPP);

	if (!tee_device_get(teedev))
		return ERR_PTR(-EINVAL);

	if (!teedev->desc->ops->shm_register ||
	    !teedev->desc->ops->shm_unregister) {
		tee_device_put(teedev);
		return ERR_PTR(-ENOTSUPP);
	}

	teedev_ctx_get(ctx);

	shm = kzalloc(sizeof(*shm), GFP_KERNEL);
	if (!shm) {
		ret = ERR_PTR(-ENOMEM);
		goto err;
	}

	shm->flags = flags | TEE_SHM_REGISTER;
	shm->teedev = teedev;
	shm->ctx = ctx;
	shm->id = -1;
	start = rounddown(addr, PAGE_SIZE);
	shm->offset = addr - start;
	shm->size = length;
	num_pages = (roundup(addr + length, PAGE_SIZE) - start) / PAGE_SIZE;
	shm->pages = kcalloc(num_pages, sizeof(*shm->pages), GFP_KERNEL);
	if (!shm->pages) {
		ret = ERR_PTR(-ENOMEM);
		goto err;
	}

	rc = get_user_pages_fast(start, num_pages, 1, shm->pages);
	if (rc > 0)
		shm->num_pages = rc;
	if (rc != num_pages) {
		if (rc >= 0)
			rc = -ENOMEM;
		ret = ERR_PTR(rc);
		goto err;
	}

	mutex_lock(&teedev->mutex);
	shm->id = idr_alloc(&teedev->idr, shm, 1, 0, GFP_KERNEL);
	mutex_unlock(&teedev->mutex);

	if (shm->id < 0) {
		ret = ERR_PTR(shm->id);
		goto err;
	}

	rc = teedev->desc->ops->shm_register(ctx, shm, shm->pages,
					     shm->num_pages, start);
	if (rc) {
		ret = ERR_PTR(rc);
		goto err;
	}

	if (flags & TEE_SHM_DMA_BUF) {
		DEFINE_DMA_BUF_EXPORT_INFO(exp_info);

		exp_info.ops = &tee_shm_dma_buf_ops;
		exp_info.size = shm->size;
		exp_info.flags = O_RDWR;
		exp_info.priv = shm;

		shm->dmabuf = dma_buf_export(&exp_info);
		if (IS_ERR(shm->dmabuf)) {
			ret = ERR_CAST(shm->dmabuf);
			teedev->desc->ops->shm_unregister(ctx, shm);
			goto err;
		}
	}

	mutex_lock(&teedev->mutex);
	list_add_tail(&shm->link, &ctx->list_shm);
	mutex_unlock(&teedev->mutex);

	return shm;
err:
	if (shm) {
		size_t n;

		if (shm->id >= 0) {
			mutex_lock(&teedev->mutex);
			idr_remove(&teedev->idr, shm->id);
			mutex_unlock(&teedev->mutex);
		}
		if (shm->pages) {
			for (n = 0; n < shm->num_pages; n++)
				put_page(shm->pages[n]);
			kfree(shm->pages);
		}
	}
	kfree(shm);
	teedev_ctx_put(ctx);
	tee_device_put(teedev);
	return ret;
}
EXPORT_SYMBOL_GPL(tee_shm_register);

/**
 * tee_shm_get_fd() - Increase reference count and return file descriptor
 * @shm:	Shared memory handle
 * @returns user space file descriptor to shared memory
 */
int tee_shm_get_fd(struct tee_shm *shm)
{
	int fd;

	if (!(shm->flags & TEE_SHM_DMA_BUF))
		return -EINVAL;

	fd = dma_buf_fd(shm->dmabuf, O_CLOEXEC);
	if (fd >= 0)
		get_dma_buf(shm->dmabuf);
	return fd;
}

/**
 * tee_shm_free() - Free shared memory
 * @shm:	Handle to shared memory to free
 */
void tee_shm_free(struct tee_shm *shm)
{
	/*
	 * dma_buf_put() decreases the dmabuf reference counter and will
	 * call tee_shm_release() when the last reference is gone.
	 *
	 * In the case of driver private memory we call tee_shm_release
	 * directly instead as it doesn't have a reference counter.
	 */
	if (shm->flags & TEE_SHM_DMA_BUF)
		dma_buf_put(shm->dmabuf);
	else
		tee_shm_release(shm);
}
EXPORT_SYMBOL_GPL(tee_shm_free);

/**
 * tee_shm_va2pa() - Get physical address of a virtual address
 * @shm:	Shared memory handle
 * @va:		Virtual address to tranlsate
 * @pa:		Returned physical address
 * @returns 0 on success and < 0 on failure
 */
int tee_shm_va2pa(struct tee_shm *shm, void *va, phys_addr_t *pa)
{
	if (!(shm->flags & TEE_SHM_MAPPED))
		return -EINVAL;
	/* Check that we're in the range of the shm */
	if ((char *)va < (char *)shm->kaddr)
		return -EINVAL;
	if ((char *)va >= ((char *)shm->kaddr + shm->size))
		return -EINVAL;

	return tee_shm_get_pa(
			shm, (unsigned long)va - (unsigned long)shm->kaddr, pa);
}
EXPORT_SYMBOL_GPL(tee_shm_va2pa);

/**
 * tee_shm_pa2va() - Get virtual address of a physical address
 * @shm:	Shared memory handle
 * @pa:		Physical address to tranlsate
 * @va:		Returned virtual address
 * @returns 0 on success and < 0 on failure
 */
int tee_shm_pa2va(struct tee_shm *shm, phys_addr_t pa, void **va)
{
	if (!(shm->flags & TEE_SHM_MAPPED))
		return -EINVAL;
	/* Check that we're in the range of the shm */
	if (pa < shm->paddr)
		return -EINVAL;
	if (pa >= (shm->paddr + shm->size))
		return -EINVAL;

	if (va) {
		void *v = tee_shm_get_va(shm, pa - shm->paddr);

		if (IS_ERR(v))
			return PTR_ERR(v);
		*va = v;
	}
	return 0;
}
EXPORT_SYMBOL_GPL(tee_shm_pa2va);

/**
 * tee_shm_get_va() - Get virtual address of a shared memory plus an offset
 * @shm:	Shared memory handle
 * @offs:	Offset from start of this shared memory
 * @returns virtual address of the shared memory + offs if offs is within
 *	the bounds of this shared memory, else an ERR_PTR
 */
void *tee_shm_get_va(struct tee_shm *shm, size_t offs)
{
	if (!(shm->flags & TEE_SHM_MAPPED))
		return ERR_PTR(-EINVAL);
	if (offs >= shm->size)
		return ERR_PTR(-EINVAL);
	return (char *)shm->kaddr + offs;
}
EXPORT_SYMBOL_GPL(tee_shm_get_va);

/**
 * tee_shm_get_pa() - Get physical address of a shared memory plus an offset
 * @shm:	Shared memory handle
 * @offs:	Offset from start of this shared memory
 * @pa:		Physical address to return
 * @returns 0 if offs is within the bounds of this shared memory, else an
 *	error code.
 */
int tee_shm_get_pa(struct tee_shm *shm, size_t offs, phys_addr_t *pa)
{
	if (offs >= shm->size)
		return -EINVAL;
	if (pa)
		*pa = shm->paddr + offs;
	return 0;
}
EXPORT_SYMBOL_GPL(tee_shm_get_pa);

/**
 * tee_shm_get_from_id() - Find shared memory object and increase reference
 * count
 * @ctx:	Context owning the shared memory
 * @id:		Id of shared memory object
 * @returns a pointer to 'struct tee_shm' on success or an ERR_PTR on failure
 */
struct tee_shm *tee_shm_get_from_id(struct tee_context *ctx, int id)
{
	struct tee_device *teedev;
	struct tee_shm *shm;

	if (!ctx)
		return ERR_PTR(-EINVAL);

	teedev = ctx->teedev;
	mutex_lock(&teedev->mutex);
	shm = idr_find(&teedev->idr, id);
	if (!shm || shm->ctx != ctx)
		shm = ERR_PTR(-EINVAL);
	else if (shm->flags & TEE_SHM_DMA_BUF)
		get_dma_buf(shm->dmabuf);
	mutex_unlock(&teedev->mutex);
	return shm;
}
EXPORT_SYMBOL_GPL(tee_shm_get_from_id);

/**
 * tee_shm_put() - Decrease reference count on a shared memory handle
 * @shm:	Shared memory handle
 */
void tee_shm_put(struct tee_shm *shm)
{
	if (shm->flags & TEE_SHM_DMA_BUF)
		dma_buf_put(shm->dmabuf);
}
EXPORT_SYMBOL_GPL(tee_shm_put);