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