1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (c) 2015-2016, Linaro Limited
4 */
5 #include <linux/device.h>
6 #include <linux/dma-buf.h>
7 #include <linux/fdtable.h>
8 #include <linux/idr.h>
9 #include <linux/sched.h>
10 #include <linux/slab.h>
11 #include <linux/tee_drv.h>
12 #include "tee_private.h"
13
tee_shm_release(struct tee_shm * shm)14 static void tee_shm_release(struct tee_shm *shm)
15 {
16 struct tee_device *teedev = shm->teedev;
17
18 mutex_lock(&teedev->mutex);
19 idr_remove(&teedev->idr, shm->id);
20 if (shm->ctx)
21 list_del(&shm->link);
22 mutex_unlock(&teedev->mutex);
23
24 if (shm->flags & TEE_SHM_POOL) {
25 struct tee_shm_pool_mgr *poolm;
26
27 if (shm->flags & TEE_SHM_DMA_BUF)
28 poolm = teedev->pool->dma_buf_mgr;
29 else
30 poolm = teedev->pool->private_mgr;
31
32 poolm->ops->free(poolm, shm);
33 } else if (shm->flags & TEE_SHM_REGISTER) {
34 size_t n;
35 int rc = teedev->desc->ops->shm_unregister(shm->ctx, shm);
36
37 if (rc)
38 dev_err(teedev->dev.parent,
39 "unregister shm %p failed: %d", shm, rc);
40
41 for (n = 0; n < shm->num_pages; n++)
42 put_page(shm->pages[n]);
43
44 kfree(shm->pages);
45 }
46
47 if (shm->ctx)
48 teedev_ctx_put(shm->ctx);
49
50 kfree(shm);
51
52 tee_device_put(teedev);
53 }
54
tee_shm_op_map_dma_buf(struct dma_buf_attachment * attach,enum dma_data_direction dir)55 static struct sg_table *tee_shm_op_map_dma_buf(struct dma_buf_attachment
56 *attach, enum dma_data_direction dir)
57 {
58 return NULL;
59 }
60
tee_shm_op_unmap_dma_buf(struct dma_buf_attachment * attach,struct sg_table * table,enum dma_data_direction dir)61 static void tee_shm_op_unmap_dma_buf(struct dma_buf_attachment *attach,
62 struct sg_table *table,
63 enum dma_data_direction dir)
64 {
65 }
66
tee_shm_op_release(struct dma_buf * dmabuf)67 static void tee_shm_op_release(struct dma_buf *dmabuf)
68 {
69 struct tee_shm *shm = dmabuf->priv;
70
71 tee_shm_release(shm);
72 }
73
tee_shm_op_map(struct dma_buf * dmabuf,unsigned long pgnum)74 static void *tee_shm_op_map(struct dma_buf *dmabuf, unsigned long pgnum)
75 {
76 return NULL;
77 }
78
tee_shm_op_mmap(struct dma_buf * dmabuf,struct vm_area_struct * vma)79 static int tee_shm_op_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma)
80 {
81 struct tee_shm *shm = dmabuf->priv;
82 size_t size = vma->vm_end - vma->vm_start;
83
84 /* Refuse sharing shared memory provided by application */
85 if (shm->flags & TEE_SHM_REGISTER)
86 return -EINVAL;
87
88 return remap_pfn_range(vma, vma->vm_start, shm->paddr >> PAGE_SHIFT,
89 size, vma->vm_page_prot);
90 }
91
92 static const struct dma_buf_ops tee_shm_dma_buf_ops = {
93 .map_dma_buf = tee_shm_op_map_dma_buf,
94 .unmap_dma_buf = tee_shm_op_unmap_dma_buf,
95 .release = tee_shm_op_release,
96 .map = tee_shm_op_map,
97 .mmap = tee_shm_op_mmap,
98 };
99
__tee_shm_alloc(struct tee_context * ctx,struct tee_device * teedev,size_t size,u32 flags)100 static struct tee_shm *__tee_shm_alloc(struct tee_context *ctx,
101 struct tee_device *teedev,
102 size_t size, u32 flags)
103 {
104 struct tee_shm_pool_mgr *poolm = NULL;
105 struct tee_shm *shm;
106 void *ret;
107 int rc;
108
109 if (ctx && ctx->teedev != teedev) {
110 dev_err(teedev->dev.parent, "ctx and teedev mismatch\n");
111 return ERR_PTR(-EINVAL);
112 }
113
114 if (!(flags & TEE_SHM_MAPPED)) {
115 dev_err(teedev->dev.parent,
116 "only mapped allocations supported\n");
117 return ERR_PTR(-EINVAL);
118 }
119
120 if ((flags & ~(TEE_SHM_MAPPED | TEE_SHM_DMA_BUF))) {
121 dev_err(teedev->dev.parent, "invalid shm flags 0x%x", flags);
122 return ERR_PTR(-EINVAL);
123 }
124
125 if (!tee_device_get(teedev))
126 return ERR_PTR(-EINVAL);
127
128 if (!teedev->pool) {
129 /* teedev has been detached from driver */
130 ret = ERR_PTR(-EINVAL);
131 goto err_dev_put;
132 }
133
134 shm = kzalloc(sizeof(*shm), GFP_KERNEL);
135 if (!shm) {
136 ret = ERR_PTR(-ENOMEM);
137 goto err_dev_put;
138 }
139
140 shm->flags = flags | TEE_SHM_POOL;
141 shm->teedev = teedev;
142 shm->ctx = ctx;
143 if (flags & TEE_SHM_DMA_BUF)
144 poolm = teedev->pool->dma_buf_mgr;
145 else
146 poolm = teedev->pool->private_mgr;
147
148 rc = poolm->ops->alloc(poolm, shm, size);
149 if (rc) {
150 ret = ERR_PTR(rc);
151 goto err_kfree;
152 }
153
154 mutex_lock(&teedev->mutex);
155 shm->id = idr_alloc(&teedev->idr, shm, 1, 0, GFP_KERNEL);
156 mutex_unlock(&teedev->mutex);
157 if (shm->id < 0) {
158 ret = ERR_PTR(shm->id);
159 goto err_pool_free;
160 }
161
162 if (flags & TEE_SHM_DMA_BUF) {
163 DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
164
165 exp_info.ops = &tee_shm_dma_buf_ops;
166 exp_info.size = shm->size;
167 exp_info.flags = O_RDWR;
168 exp_info.priv = shm;
169
170 shm->dmabuf = dma_buf_export(&exp_info);
171 if (IS_ERR(shm->dmabuf)) {
172 ret = ERR_CAST(shm->dmabuf);
173 goto err_rem;
174 }
175 }
176
177 if (ctx) {
178 teedev_ctx_get(ctx);
179 mutex_lock(&teedev->mutex);
180 list_add_tail(&shm->link, &ctx->list_shm);
181 mutex_unlock(&teedev->mutex);
182 }
183
184 return shm;
185 err_rem:
186 mutex_lock(&teedev->mutex);
187 idr_remove(&teedev->idr, shm->id);
188 mutex_unlock(&teedev->mutex);
189 err_pool_free:
190 poolm->ops->free(poolm, shm);
191 err_kfree:
192 kfree(shm);
193 err_dev_put:
194 tee_device_put(teedev);
195 return ret;
196 }
197
198 /**
199 * tee_shm_alloc() - Allocate shared memory
200 * @ctx: Context that allocates the shared memory
201 * @size: Requested size of shared memory
202 * @flags: Flags setting properties for the requested shared memory.
203 *
204 * Memory allocated as global shared memory is automatically freed when the
205 * TEE file pointer is closed. The @flags field uses the bits defined by
206 * TEE_SHM_* in <linux/tee_drv.h>. TEE_SHM_MAPPED must currently always be
207 * set. If TEE_SHM_DMA_BUF global shared memory will be allocated and
208 * associated with a dma-buf handle, else driver private memory.
209 */
tee_shm_alloc(struct tee_context * ctx,size_t size,u32 flags)210 struct tee_shm *tee_shm_alloc(struct tee_context *ctx, size_t size, u32 flags)
211 {
212 return __tee_shm_alloc(ctx, ctx->teedev, size, flags);
213 }
214 EXPORT_SYMBOL_GPL(tee_shm_alloc);
215
tee_shm_priv_alloc(struct tee_device * teedev,size_t size)216 struct tee_shm *tee_shm_priv_alloc(struct tee_device *teedev, size_t size)
217 {
218 return __tee_shm_alloc(NULL, teedev, size, TEE_SHM_MAPPED);
219 }
220 EXPORT_SYMBOL_GPL(tee_shm_priv_alloc);
221
tee_shm_register(struct tee_context * ctx,unsigned long addr,size_t length,u32 flags)222 struct tee_shm *tee_shm_register(struct tee_context *ctx, unsigned long addr,
223 size_t length, u32 flags)
224 {
225 struct tee_device *teedev = ctx->teedev;
226 const u32 req_flags = TEE_SHM_DMA_BUF | TEE_SHM_USER_MAPPED;
227 struct tee_shm *shm;
228 void *ret;
229 int rc;
230 int num_pages;
231 unsigned long start;
232
233 if (flags != req_flags)
234 return ERR_PTR(-ENOTSUPP);
235
236 if (!tee_device_get(teedev))
237 return ERR_PTR(-EINVAL);
238
239 if (!teedev->desc->ops->shm_register ||
240 !teedev->desc->ops->shm_unregister) {
241 tee_device_put(teedev);
242 return ERR_PTR(-ENOTSUPP);
243 }
244
245 teedev_ctx_get(ctx);
246
247 shm = kzalloc(sizeof(*shm), GFP_KERNEL);
248 if (!shm) {
249 ret = ERR_PTR(-ENOMEM);
250 goto err;
251 }
252
253 shm->flags = flags | TEE_SHM_REGISTER;
254 shm->teedev = teedev;
255 shm->ctx = ctx;
256 shm->id = -1;
257 addr = untagged_addr(addr);
258 start = rounddown(addr, PAGE_SIZE);
259 shm->offset = addr - start;
260 shm->size = length;
261 num_pages = (roundup(addr + length, PAGE_SIZE) - start) / PAGE_SIZE;
262 shm->pages = kcalloc(num_pages, sizeof(*shm->pages), GFP_KERNEL);
263 if (!shm->pages) {
264 ret = ERR_PTR(-ENOMEM);
265 goto err;
266 }
267
268 rc = get_user_pages_fast(start, num_pages, FOLL_WRITE, shm->pages);
269 if (rc > 0)
270 shm->num_pages = rc;
271 if (rc != num_pages) {
272 if (rc >= 0)
273 rc = -ENOMEM;
274 ret = ERR_PTR(rc);
275 goto err;
276 }
277
278 mutex_lock(&teedev->mutex);
279 shm->id = idr_alloc(&teedev->idr, shm, 1, 0, GFP_KERNEL);
280 mutex_unlock(&teedev->mutex);
281
282 if (shm->id < 0) {
283 ret = ERR_PTR(shm->id);
284 goto err;
285 }
286
287 rc = teedev->desc->ops->shm_register(ctx, shm, shm->pages,
288 shm->num_pages, start);
289 if (rc) {
290 ret = ERR_PTR(rc);
291 goto err;
292 }
293
294 if (flags & TEE_SHM_DMA_BUF) {
295 DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
296
297 exp_info.ops = &tee_shm_dma_buf_ops;
298 exp_info.size = shm->size;
299 exp_info.flags = O_RDWR;
300 exp_info.priv = shm;
301
302 shm->dmabuf = dma_buf_export(&exp_info);
303 if (IS_ERR(shm->dmabuf)) {
304 ret = ERR_CAST(shm->dmabuf);
305 teedev->desc->ops->shm_unregister(ctx, shm);
306 goto err;
307 }
308 }
309
310 mutex_lock(&teedev->mutex);
311 list_add_tail(&shm->link, &ctx->list_shm);
312 mutex_unlock(&teedev->mutex);
313
314 return shm;
315 err:
316 if (shm) {
317 size_t n;
318
319 if (shm->id >= 0) {
320 mutex_lock(&teedev->mutex);
321 idr_remove(&teedev->idr, shm->id);
322 mutex_unlock(&teedev->mutex);
323 }
324 if (shm->pages) {
325 for (n = 0; n < shm->num_pages; n++)
326 put_page(shm->pages[n]);
327 kfree(shm->pages);
328 }
329 }
330 kfree(shm);
331 teedev_ctx_put(ctx);
332 tee_device_put(teedev);
333 return ret;
334 }
335 EXPORT_SYMBOL_GPL(tee_shm_register);
336
337 /**
338 * tee_shm_get_fd() - Increase reference count and return file descriptor
339 * @shm: Shared memory handle
340 * @returns user space file descriptor to shared memory
341 */
tee_shm_get_fd(struct tee_shm * shm)342 int tee_shm_get_fd(struct tee_shm *shm)
343 {
344 int fd;
345
346 if (!(shm->flags & TEE_SHM_DMA_BUF))
347 return -EINVAL;
348
349 get_dma_buf(shm->dmabuf);
350 fd = dma_buf_fd(shm->dmabuf, O_CLOEXEC);
351 if (fd < 0)
352 dma_buf_put(shm->dmabuf);
353 return fd;
354 }
355
356 /**
357 * tee_shm_free() - Free shared memory
358 * @shm: Handle to shared memory to free
359 */
tee_shm_free(struct tee_shm * shm)360 void tee_shm_free(struct tee_shm *shm)
361 {
362 /*
363 * dma_buf_put() decreases the dmabuf reference counter and will
364 * call tee_shm_release() when the last reference is gone.
365 *
366 * In the case of driver private memory we call tee_shm_release
367 * directly instead as it doesn't have a reference counter.
368 */
369 if (shm->flags & TEE_SHM_DMA_BUF)
370 dma_buf_put(shm->dmabuf);
371 else
372 tee_shm_release(shm);
373 }
374 EXPORT_SYMBOL_GPL(tee_shm_free);
375
376 /**
377 * tee_shm_va2pa() - Get physical address of a virtual address
378 * @shm: Shared memory handle
379 * @va: Virtual address to tranlsate
380 * @pa: Returned physical address
381 * @returns 0 on success and < 0 on failure
382 */
tee_shm_va2pa(struct tee_shm * shm,void * va,phys_addr_t * pa)383 int tee_shm_va2pa(struct tee_shm *shm, void *va, phys_addr_t *pa)
384 {
385 if (!(shm->flags & TEE_SHM_MAPPED))
386 return -EINVAL;
387 /* Check that we're in the range of the shm */
388 if ((char *)va < (char *)shm->kaddr)
389 return -EINVAL;
390 if ((char *)va >= ((char *)shm->kaddr + shm->size))
391 return -EINVAL;
392
393 return tee_shm_get_pa(
394 shm, (unsigned long)va - (unsigned long)shm->kaddr, pa);
395 }
396 EXPORT_SYMBOL_GPL(tee_shm_va2pa);
397
398 /**
399 * tee_shm_pa2va() - Get virtual address of a physical address
400 * @shm: Shared memory handle
401 * @pa: Physical address to tranlsate
402 * @va: Returned virtual address
403 * @returns 0 on success and < 0 on failure
404 */
tee_shm_pa2va(struct tee_shm * shm,phys_addr_t pa,void ** va)405 int tee_shm_pa2va(struct tee_shm *shm, phys_addr_t pa, void **va)
406 {
407 if (!(shm->flags & TEE_SHM_MAPPED))
408 return -EINVAL;
409 /* Check that we're in the range of the shm */
410 if (pa < shm->paddr)
411 return -EINVAL;
412 if (pa >= (shm->paddr + shm->size))
413 return -EINVAL;
414
415 if (va) {
416 void *v = tee_shm_get_va(shm, pa - shm->paddr);
417
418 if (IS_ERR(v))
419 return PTR_ERR(v);
420 *va = v;
421 }
422 return 0;
423 }
424 EXPORT_SYMBOL_GPL(tee_shm_pa2va);
425
426 /**
427 * tee_shm_get_va() - Get virtual address of a shared memory plus an offset
428 * @shm: Shared memory handle
429 * @offs: Offset from start of this shared memory
430 * @returns virtual address of the shared memory + offs if offs is within
431 * the bounds of this shared memory, else an ERR_PTR
432 */
tee_shm_get_va(struct tee_shm * shm,size_t offs)433 void *tee_shm_get_va(struct tee_shm *shm, size_t offs)
434 {
435 if (!(shm->flags & TEE_SHM_MAPPED))
436 return ERR_PTR(-EINVAL);
437 if (offs >= shm->size)
438 return ERR_PTR(-EINVAL);
439 return (char *)shm->kaddr + offs;
440 }
441 EXPORT_SYMBOL_GPL(tee_shm_get_va);
442
443 /**
444 * tee_shm_get_pa() - Get physical address of a shared memory plus an offset
445 * @shm: Shared memory handle
446 * @offs: Offset from start of this shared memory
447 * @pa: Physical address to return
448 * @returns 0 if offs is within the bounds of this shared memory, else an
449 * error code.
450 */
tee_shm_get_pa(struct tee_shm * shm,size_t offs,phys_addr_t * pa)451 int tee_shm_get_pa(struct tee_shm *shm, size_t offs, phys_addr_t *pa)
452 {
453 if (offs >= shm->size)
454 return -EINVAL;
455 if (pa)
456 *pa = shm->paddr + offs;
457 return 0;
458 }
459 EXPORT_SYMBOL_GPL(tee_shm_get_pa);
460
461 /**
462 * tee_shm_get_from_id() - Find shared memory object and increase reference
463 * count
464 * @ctx: Context owning the shared memory
465 * @id: Id of shared memory object
466 * @returns a pointer to 'struct tee_shm' on success or an ERR_PTR on failure
467 */
tee_shm_get_from_id(struct tee_context * ctx,int id)468 struct tee_shm *tee_shm_get_from_id(struct tee_context *ctx, int id)
469 {
470 struct tee_device *teedev;
471 struct tee_shm *shm;
472
473 if (!ctx)
474 return ERR_PTR(-EINVAL);
475
476 teedev = ctx->teedev;
477 mutex_lock(&teedev->mutex);
478 shm = idr_find(&teedev->idr, id);
479 if (!shm || shm->ctx != ctx)
480 shm = ERR_PTR(-EINVAL);
481 else if (shm->flags & TEE_SHM_DMA_BUF)
482 get_dma_buf(shm->dmabuf);
483 mutex_unlock(&teedev->mutex);
484 return shm;
485 }
486 EXPORT_SYMBOL_GPL(tee_shm_get_from_id);
487
488 /**
489 * tee_shm_put() - Decrease reference count on a shared memory handle
490 * @shm: Shared memory handle
491 */
tee_shm_put(struct tee_shm * shm)492 void tee_shm_put(struct tee_shm *shm)
493 {
494 if (shm->flags & TEE_SHM_DMA_BUF)
495 dma_buf_put(shm->dmabuf);
496 }
497 EXPORT_SYMBOL_GPL(tee_shm_put);
498