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 <linux/uio.h> 13 #include "tee_private.h" 14 15 static void release_registered_pages(struct tee_shm *shm) 16 { 17 if (shm->pages) { 18 if (shm->flags & TEE_SHM_USER_MAPPED) { 19 unpin_user_pages(shm->pages, shm->num_pages); 20 } else { 21 size_t n; 22 23 for (n = 0; n < shm->num_pages; n++) 24 put_page(shm->pages[n]); 25 } 26 27 kfree(shm->pages); 28 } 29 } 30 31 static void tee_shm_release(struct tee_shm *shm) 32 { 33 struct tee_device *teedev = shm->ctx->teedev; 34 35 if (shm->flags & TEE_SHM_DMA_BUF) { 36 mutex_lock(&teedev->mutex); 37 idr_remove(&teedev->idr, shm->id); 38 mutex_unlock(&teedev->mutex); 39 } 40 41 if (shm->flags & TEE_SHM_POOL) { 42 struct tee_shm_pool_mgr *poolm; 43 44 if (shm->flags & TEE_SHM_DMA_BUF) 45 poolm = teedev->pool->dma_buf_mgr; 46 else 47 poolm = teedev->pool->private_mgr; 48 49 poolm->ops->free(poolm, shm); 50 } else if (shm->flags & TEE_SHM_REGISTER) { 51 int rc = teedev->desc->ops->shm_unregister(shm->ctx, shm); 52 53 if (rc) 54 dev_err(teedev->dev.parent, 55 "unregister shm %p failed: %d", shm, rc); 56 57 release_registered_pages(shm); 58 } 59 60 teedev_ctx_put(shm->ctx); 61 62 kfree(shm); 63 64 tee_device_put(teedev); 65 } 66 67 static struct sg_table *tee_shm_op_map_dma_buf(struct dma_buf_attachment 68 *attach, enum dma_data_direction dir) 69 { 70 return NULL; 71 } 72 73 static void tee_shm_op_unmap_dma_buf(struct dma_buf_attachment *attach, 74 struct sg_table *table, 75 enum dma_data_direction dir) 76 { 77 } 78 79 static void tee_shm_op_release(struct dma_buf *dmabuf) 80 { 81 struct tee_shm *shm = dmabuf->priv; 82 83 tee_shm_release(shm); 84 } 85 86 static int tee_shm_op_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma) 87 { 88 struct tee_shm *shm = dmabuf->priv; 89 size_t size = vma->vm_end - vma->vm_start; 90 91 /* Refuse sharing shared memory provided by application */ 92 if (shm->flags & TEE_SHM_USER_MAPPED) 93 return -EINVAL; 94 95 return remap_pfn_range(vma, vma->vm_start, shm->paddr >> PAGE_SHIFT, 96 size, vma->vm_page_prot); 97 } 98 99 static const struct dma_buf_ops tee_shm_dma_buf_ops = { 100 .map_dma_buf = tee_shm_op_map_dma_buf, 101 .unmap_dma_buf = tee_shm_op_unmap_dma_buf, 102 .release = tee_shm_op_release, 103 .mmap = tee_shm_op_mmap, 104 }; 105 106 struct tee_shm *tee_shm_alloc(struct tee_context *ctx, size_t size, u32 flags) 107 { 108 struct tee_device *teedev = ctx->teedev; 109 struct tee_shm_pool_mgr *poolm = NULL; 110 struct tee_shm *shm; 111 void *ret; 112 int rc; 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 | TEE_SHM_PRIV))) { 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->ctx = ctx; 142 if (flags & TEE_SHM_DMA_BUF) 143 poolm = teedev->pool->dma_buf_mgr; 144 else 145 poolm = teedev->pool->private_mgr; 146 147 rc = poolm->ops->alloc(poolm, shm, size); 148 if (rc) { 149 ret = ERR_PTR(rc); 150 goto err_kfree; 151 } 152 153 154 if (flags & TEE_SHM_DMA_BUF) { 155 DEFINE_DMA_BUF_EXPORT_INFO(exp_info); 156 157 mutex_lock(&teedev->mutex); 158 shm->id = idr_alloc(&teedev->idr, shm, 1, 0, GFP_KERNEL); 159 mutex_unlock(&teedev->mutex); 160 if (shm->id < 0) { 161 ret = ERR_PTR(shm->id); 162 goto err_pool_free; 163 } 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 teedev_ctx_get(ctx); 178 179 return shm; 180 err_rem: 181 if (flags & TEE_SHM_DMA_BUF) { 182 mutex_lock(&teedev->mutex); 183 idr_remove(&teedev->idr, shm->id); 184 mutex_unlock(&teedev->mutex); 185 } 186 err_pool_free: 187 poolm->ops->free(poolm, shm); 188 err_kfree: 189 kfree(shm); 190 err_dev_put: 191 tee_device_put(teedev); 192 return ret; 193 } 194 EXPORT_SYMBOL_GPL(tee_shm_alloc); 195 196 /** 197 * tee_shm_alloc_kernel_buf() - Allocate shared memory for kernel buffer 198 * @ctx: Context that allocates the shared memory 199 * @size: Requested size of shared memory 200 * 201 * The returned memory registered in secure world and is suitable to be 202 * passed as a memory buffer in parameter argument to 203 * tee_client_invoke_func(). The memory allocated is later freed with a 204 * call to tee_shm_free(). 205 * 206 * @returns a pointer to 'struct tee_shm' 207 */ 208 struct tee_shm *tee_shm_alloc_kernel_buf(struct tee_context *ctx, size_t size) 209 { 210 return tee_shm_alloc(ctx, size, TEE_SHM_MAPPED); 211 } 212 EXPORT_SYMBOL_GPL(tee_shm_alloc_kernel_buf); 213 214 struct tee_shm *tee_shm_register(struct tee_context *ctx, unsigned long addr, 215 size_t length, u32 flags) 216 { 217 struct tee_device *teedev = ctx->teedev; 218 const u32 req_user_flags = TEE_SHM_DMA_BUF | TEE_SHM_USER_MAPPED; 219 const u32 req_kernel_flags = TEE_SHM_DMA_BUF | TEE_SHM_KERNEL_MAPPED; 220 struct tee_shm *shm; 221 void *ret; 222 int rc; 223 int num_pages; 224 unsigned long start; 225 226 if (flags != req_user_flags && flags != req_kernel_flags) 227 return ERR_PTR(-ENOTSUPP); 228 229 if (!tee_device_get(teedev)) 230 return ERR_PTR(-EINVAL); 231 232 if (!teedev->desc->ops->shm_register || 233 !teedev->desc->ops->shm_unregister) { 234 tee_device_put(teedev); 235 return ERR_PTR(-ENOTSUPP); 236 } 237 238 teedev_ctx_get(ctx); 239 240 shm = kzalloc(sizeof(*shm), GFP_KERNEL); 241 if (!shm) { 242 ret = ERR_PTR(-ENOMEM); 243 goto err; 244 } 245 246 shm->flags = flags | TEE_SHM_REGISTER; 247 shm->ctx = ctx; 248 shm->id = -1; 249 addr = untagged_addr(addr); 250 start = rounddown(addr, PAGE_SIZE); 251 shm->offset = addr - start; 252 shm->size = length; 253 num_pages = (roundup(addr + length, PAGE_SIZE) - start) / PAGE_SIZE; 254 shm->pages = kcalloc(num_pages, sizeof(*shm->pages), GFP_KERNEL); 255 if (!shm->pages) { 256 ret = ERR_PTR(-ENOMEM); 257 goto err; 258 } 259 260 if (flags & TEE_SHM_USER_MAPPED) { 261 rc = pin_user_pages_fast(start, num_pages, FOLL_WRITE, 262 shm->pages); 263 } else { 264 struct kvec *kiov; 265 int i; 266 267 kiov = kcalloc(num_pages, sizeof(*kiov), GFP_KERNEL); 268 if (!kiov) { 269 ret = ERR_PTR(-ENOMEM); 270 goto err; 271 } 272 273 for (i = 0; i < num_pages; i++) { 274 kiov[i].iov_base = (void *)(start + i * PAGE_SIZE); 275 kiov[i].iov_len = PAGE_SIZE; 276 } 277 278 rc = get_kernel_pages(kiov, num_pages, 0, shm->pages); 279 kfree(kiov); 280 } 281 if (rc > 0) 282 shm->num_pages = rc; 283 if (rc != num_pages) { 284 if (rc >= 0) 285 rc = -ENOMEM; 286 ret = ERR_PTR(rc); 287 goto err; 288 } 289 290 mutex_lock(&teedev->mutex); 291 shm->id = idr_alloc(&teedev->idr, shm, 1, 0, GFP_KERNEL); 292 mutex_unlock(&teedev->mutex); 293 294 if (shm->id < 0) { 295 ret = ERR_PTR(shm->id); 296 goto err; 297 } 298 299 rc = teedev->desc->ops->shm_register(ctx, shm, shm->pages, 300 shm->num_pages, start); 301 if (rc) { 302 ret = ERR_PTR(rc); 303 goto err; 304 } 305 306 if (flags & TEE_SHM_DMA_BUF) { 307 DEFINE_DMA_BUF_EXPORT_INFO(exp_info); 308 309 exp_info.ops = &tee_shm_dma_buf_ops; 310 exp_info.size = shm->size; 311 exp_info.flags = O_RDWR; 312 exp_info.priv = shm; 313 314 shm->dmabuf = dma_buf_export(&exp_info); 315 if (IS_ERR(shm->dmabuf)) { 316 ret = ERR_CAST(shm->dmabuf); 317 teedev->desc->ops->shm_unregister(ctx, shm); 318 goto err; 319 } 320 } 321 322 return shm; 323 err: 324 if (shm) { 325 if (shm->id >= 0) { 326 mutex_lock(&teedev->mutex); 327 idr_remove(&teedev->idr, shm->id); 328 mutex_unlock(&teedev->mutex); 329 } 330 release_registered_pages(shm); 331 } 332 kfree(shm); 333 teedev_ctx_put(ctx); 334 tee_device_put(teedev); 335 return ret; 336 } 337 EXPORT_SYMBOL_GPL(tee_shm_register); 338 339 /** 340 * tee_shm_get_fd() - Increase reference count and return file descriptor 341 * @shm: Shared memory handle 342 * @returns user space file descriptor to shared memory 343 */ 344 int tee_shm_get_fd(struct tee_shm *shm) 345 { 346 int fd; 347 348 if (!(shm->flags & TEE_SHM_DMA_BUF)) 349 return -EINVAL; 350 351 get_dma_buf(shm->dmabuf); 352 fd = dma_buf_fd(shm->dmabuf, O_CLOEXEC); 353 if (fd < 0) 354 dma_buf_put(shm->dmabuf); 355 return fd; 356 } 357 358 /** 359 * tee_shm_free() - Free shared memory 360 * @shm: Handle to shared memory to free 361 */ 362 void tee_shm_free(struct tee_shm *shm) 363 { 364 /* 365 * dma_buf_put() decreases the dmabuf reference counter and will 366 * call tee_shm_release() when the last reference is gone. 367 * 368 * In the case of driver private memory we call tee_shm_release 369 * directly instead as it doesn't have a reference counter. 370 */ 371 if (shm->flags & TEE_SHM_DMA_BUF) 372 dma_buf_put(shm->dmabuf); 373 else 374 tee_shm_release(shm); 375 } 376 EXPORT_SYMBOL_GPL(tee_shm_free); 377 378 /** 379 * tee_shm_va2pa() - Get physical address of a virtual address 380 * @shm: Shared memory handle 381 * @va: Virtual address to tranlsate 382 * @pa: Returned physical address 383 * @returns 0 on success and < 0 on failure 384 */ 385 int tee_shm_va2pa(struct tee_shm *shm, void *va, phys_addr_t *pa) 386 { 387 if (!(shm->flags & TEE_SHM_MAPPED)) 388 return -EINVAL; 389 /* Check that we're in the range of the shm */ 390 if ((char *)va < (char *)shm->kaddr) 391 return -EINVAL; 392 if ((char *)va >= ((char *)shm->kaddr + shm->size)) 393 return -EINVAL; 394 395 return tee_shm_get_pa( 396 shm, (unsigned long)va - (unsigned long)shm->kaddr, pa); 397 } 398 EXPORT_SYMBOL_GPL(tee_shm_va2pa); 399 400 /** 401 * tee_shm_pa2va() - Get virtual address of a physical address 402 * @shm: Shared memory handle 403 * @pa: Physical address to tranlsate 404 * @va: Returned virtual address 405 * @returns 0 on success and < 0 on failure 406 */ 407 int tee_shm_pa2va(struct tee_shm *shm, phys_addr_t pa, void **va) 408 { 409 if (!(shm->flags & TEE_SHM_MAPPED)) 410 return -EINVAL; 411 /* Check that we're in the range of the shm */ 412 if (pa < shm->paddr) 413 return -EINVAL; 414 if (pa >= (shm->paddr + shm->size)) 415 return -EINVAL; 416 417 if (va) { 418 void *v = tee_shm_get_va(shm, pa - shm->paddr); 419 420 if (IS_ERR(v)) 421 return PTR_ERR(v); 422 *va = v; 423 } 424 return 0; 425 } 426 EXPORT_SYMBOL_GPL(tee_shm_pa2va); 427 428 /** 429 * tee_shm_get_va() - Get virtual address of a shared memory plus an offset 430 * @shm: Shared memory handle 431 * @offs: Offset from start of this shared memory 432 * @returns virtual address of the shared memory + offs if offs is within 433 * the bounds of this shared memory, else an ERR_PTR 434 */ 435 void *tee_shm_get_va(struct tee_shm *shm, size_t offs) 436 { 437 if (!(shm->flags & TEE_SHM_MAPPED)) 438 return ERR_PTR(-EINVAL); 439 if (offs >= shm->size) 440 return ERR_PTR(-EINVAL); 441 return (char *)shm->kaddr + offs; 442 } 443 EXPORT_SYMBOL_GPL(tee_shm_get_va); 444 445 /** 446 * tee_shm_get_pa() - Get physical address of a shared memory plus an offset 447 * @shm: Shared memory handle 448 * @offs: Offset from start of this shared memory 449 * @pa: Physical address to return 450 * @returns 0 if offs is within the bounds of this shared memory, else an 451 * error code. 452 */ 453 int tee_shm_get_pa(struct tee_shm *shm, size_t offs, phys_addr_t *pa) 454 { 455 if (offs >= shm->size) 456 return -EINVAL; 457 if (pa) 458 *pa = shm->paddr + offs; 459 return 0; 460 } 461 EXPORT_SYMBOL_GPL(tee_shm_get_pa); 462 463 /** 464 * tee_shm_get_from_id() - Find shared memory object and increase reference 465 * count 466 * @ctx: Context owning the shared memory 467 * @id: Id of shared memory object 468 * @returns a pointer to 'struct tee_shm' on success or an ERR_PTR on failure 469 */ 470 struct tee_shm *tee_shm_get_from_id(struct tee_context *ctx, int id) 471 { 472 struct tee_device *teedev; 473 struct tee_shm *shm; 474 475 if (!ctx) 476 return ERR_PTR(-EINVAL); 477 478 teedev = ctx->teedev; 479 mutex_lock(&teedev->mutex); 480 shm = idr_find(&teedev->idr, id); 481 if (!shm || shm->ctx != ctx) 482 shm = ERR_PTR(-EINVAL); 483 else if (shm->flags & TEE_SHM_DMA_BUF) 484 get_dma_buf(shm->dmabuf); 485 mutex_unlock(&teedev->mutex); 486 return shm; 487 } 488 EXPORT_SYMBOL_GPL(tee_shm_get_from_id); 489 490 /** 491 * tee_shm_put() - Decrease reference count on a shared memory handle 492 * @shm: Shared memory handle 493 */ 494 void tee_shm_put(struct tee_shm *shm) 495 { 496 if (shm->flags & TEE_SHM_DMA_BUF) 497 dma_buf_put(shm->dmabuf); 498 } 499 EXPORT_SYMBOL_GPL(tee_shm_put); 500