1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * NVIDIA Tegra DRM GEM helper functions 4 * 5 * Copyright (C) 2012 Sascha Hauer, Pengutronix 6 * Copyright (C) 2013-2015 NVIDIA CORPORATION, All rights reserved. 7 * 8 * Based on the GEM/CMA helpers 9 * 10 * Copyright (c) 2011 Samsung Electronics Co., Ltd. 11 */ 12 13 #include <linux/dma-buf.h> 14 #include <linux/iommu.h> 15 16 #include <drm/drm_drv.h> 17 #include <drm/drm_prime.h> 18 #include <drm/tegra_drm.h> 19 20 #include "drm.h" 21 #include "gem.h" 22 23 static void tegra_bo_put(struct host1x_bo *bo) 24 { 25 struct tegra_bo *obj = host1x_to_tegra_bo(bo); 26 27 drm_gem_object_put(&obj->gem); 28 } 29 30 /* XXX move this into lib/scatterlist.c? */ 31 static int sg_alloc_table_from_sg(struct sg_table *sgt, struct scatterlist *sg, 32 unsigned int nents, gfp_t gfp_mask) 33 { 34 struct scatterlist *dst; 35 unsigned int i; 36 int err; 37 38 err = sg_alloc_table(sgt, nents, gfp_mask); 39 if (err < 0) 40 return err; 41 42 dst = sgt->sgl; 43 44 for (i = 0; i < nents; i++) { 45 sg_set_page(dst, sg_page(sg), sg->length, 0); 46 dst = sg_next(dst); 47 sg = sg_next(sg); 48 } 49 50 return 0; 51 } 52 53 static struct sg_table *tegra_bo_pin(struct device *dev, struct host1x_bo *bo, 54 dma_addr_t *phys) 55 { 56 struct tegra_bo *obj = host1x_to_tegra_bo(bo); 57 struct sg_table *sgt; 58 int err; 59 60 /* 61 * If we've manually mapped the buffer object through the IOMMU, make 62 * sure to return the IOVA address of our mapping. 63 * 64 * Similarly, for buffers that have been allocated by the DMA API the 65 * physical address can be used for devices that are not attached to 66 * an IOMMU. For these devices, callers must pass a valid pointer via 67 * the @phys argument. 68 * 69 * Imported buffers were also already mapped at import time, so the 70 * existing mapping can be reused. 71 */ 72 if (phys) { 73 *phys = obj->iova; 74 return NULL; 75 } 76 77 /* 78 * If we don't have a mapping for this buffer yet, return an SG table 79 * so that host1x can do the mapping for us via the DMA API. 80 */ 81 sgt = kzalloc(sizeof(*sgt), GFP_KERNEL); 82 if (!sgt) 83 return ERR_PTR(-ENOMEM); 84 85 if (obj->pages) { 86 /* 87 * If the buffer object was allocated from the explicit IOMMU 88 * API code paths, construct an SG table from the pages. 89 */ 90 err = sg_alloc_table_from_pages(sgt, obj->pages, obj->num_pages, 91 0, obj->gem.size, GFP_KERNEL); 92 if (err < 0) 93 goto free; 94 } else if (obj->sgt) { 95 /* 96 * If the buffer object already has an SG table but no pages 97 * were allocated for it, it means the buffer was imported and 98 * the SG table needs to be copied to avoid overwriting any 99 * other potential users of the original SG table. 100 */ 101 err = sg_alloc_table_from_sg(sgt, obj->sgt->sgl, obj->sgt->nents, 102 GFP_KERNEL); 103 if (err < 0) 104 goto free; 105 } else { 106 /* 107 * If the buffer object had no pages allocated and if it was 108 * not imported, it had to be allocated with the DMA API, so 109 * the DMA API helper can be used. 110 */ 111 err = dma_get_sgtable(dev, sgt, obj->vaddr, obj->iova, 112 obj->gem.size); 113 if (err < 0) 114 goto free; 115 } 116 117 return sgt; 118 119 free: 120 kfree(sgt); 121 return ERR_PTR(err); 122 } 123 124 static void tegra_bo_unpin(struct device *dev, struct sg_table *sgt) 125 { 126 if (sgt) { 127 sg_free_table(sgt); 128 kfree(sgt); 129 } 130 } 131 132 static void *tegra_bo_mmap(struct host1x_bo *bo) 133 { 134 struct tegra_bo *obj = host1x_to_tegra_bo(bo); 135 struct dma_buf_map map; 136 int ret; 137 138 if (obj->vaddr) { 139 return obj->vaddr; 140 } else if (obj->gem.import_attach) { 141 ret = dma_buf_vmap(obj->gem.import_attach->dmabuf, &map); 142 return ret ? NULL : map.vaddr; 143 } else { 144 return vmap(obj->pages, obj->num_pages, VM_MAP, 145 pgprot_writecombine(PAGE_KERNEL)); 146 } 147 } 148 149 static void tegra_bo_munmap(struct host1x_bo *bo, void *addr) 150 { 151 struct tegra_bo *obj = host1x_to_tegra_bo(bo); 152 153 if (obj->vaddr) 154 return; 155 else if (obj->gem.import_attach) 156 dma_buf_vunmap(obj->gem.import_attach->dmabuf, addr); 157 else 158 vunmap(addr); 159 } 160 161 static struct host1x_bo *tegra_bo_get(struct host1x_bo *bo) 162 { 163 struct tegra_bo *obj = host1x_to_tegra_bo(bo); 164 165 drm_gem_object_get(&obj->gem); 166 167 return bo; 168 } 169 170 static const struct host1x_bo_ops tegra_bo_ops = { 171 .get = tegra_bo_get, 172 .put = tegra_bo_put, 173 .pin = tegra_bo_pin, 174 .unpin = tegra_bo_unpin, 175 .mmap = tegra_bo_mmap, 176 .munmap = tegra_bo_munmap, 177 }; 178 179 static int tegra_bo_iommu_map(struct tegra_drm *tegra, struct tegra_bo *bo) 180 { 181 int prot = IOMMU_READ | IOMMU_WRITE; 182 int err; 183 184 if (bo->mm) 185 return -EBUSY; 186 187 bo->mm = kzalloc(sizeof(*bo->mm), GFP_KERNEL); 188 if (!bo->mm) 189 return -ENOMEM; 190 191 mutex_lock(&tegra->mm_lock); 192 193 err = drm_mm_insert_node_generic(&tegra->mm, 194 bo->mm, bo->gem.size, PAGE_SIZE, 0, 0); 195 if (err < 0) { 196 dev_err(tegra->drm->dev, "out of I/O virtual memory: %d\n", 197 err); 198 goto unlock; 199 } 200 201 bo->iova = bo->mm->start; 202 203 bo->size = iommu_map_sg(tegra->domain, bo->iova, bo->sgt->sgl, 204 bo->sgt->nents, prot); 205 if (!bo->size) { 206 dev_err(tegra->drm->dev, "failed to map buffer\n"); 207 err = -ENOMEM; 208 goto remove; 209 } 210 211 mutex_unlock(&tegra->mm_lock); 212 213 return 0; 214 215 remove: 216 drm_mm_remove_node(bo->mm); 217 unlock: 218 mutex_unlock(&tegra->mm_lock); 219 kfree(bo->mm); 220 return err; 221 } 222 223 static int tegra_bo_iommu_unmap(struct tegra_drm *tegra, struct tegra_bo *bo) 224 { 225 if (!bo->mm) 226 return 0; 227 228 mutex_lock(&tegra->mm_lock); 229 iommu_unmap(tegra->domain, bo->iova, bo->size); 230 drm_mm_remove_node(bo->mm); 231 mutex_unlock(&tegra->mm_lock); 232 233 kfree(bo->mm); 234 235 return 0; 236 } 237 238 static const struct drm_gem_object_funcs tegra_gem_object_funcs = { 239 .free = tegra_bo_free_object, 240 .export = tegra_gem_prime_export, 241 .vm_ops = &tegra_bo_vm_ops, 242 }; 243 244 static struct tegra_bo *tegra_bo_alloc_object(struct drm_device *drm, 245 size_t size) 246 { 247 struct tegra_bo *bo; 248 int err; 249 250 bo = kzalloc(sizeof(*bo), GFP_KERNEL); 251 if (!bo) 252 return ERR_PTR(-ENOMEM); 253 254 bo->gem.funcs = &tegra_gem_object_funcs; 255 256 host1x_bo_init(&bo->base, &tegra_bo_ops); 257 size = round_up(size, PAGE_SIZE); 258 259 err = drm_gem_object_init(drm, &bo->gem, size); 260 if (err < 0) 261 goto free; 262 263 err = drm_gem_create_mmap_offset(&bo->gem); 264 if (err < 0) 265 goto release; 266 267 return bo; 268 269 release: 270 drm_gem_object_release(&bo->gem); 271 free: 272 kfree(bo); 273 return ERR_PTR(err); 274 } 275 276 static void tegra_bo_free(struct drm_device *drm, struct tegra_bo *bo) 277 { 278 if (bo->pages) { 279 dma_unmap_sg(drm->dev, bo->sgt->sgl, bo->sgt->nents, 280 DMA_FROM_DEVICE); 281 drm_gem_put_pages(&bo->gem, bo->pages, true, true); 282 sg_free_table(bo->sgt); 283 kfree(bo->sgt); 284 } else if (bo->vaddr) { 285 dma_free_wc(drm->dev, bo->gem.size, bo->vaddr, bo->iova); 286 } 287 } 288 289 static int tegra_bo_get_pages(struct drm_device *drm, struct tegra_bo *bo) 290 { 291 int err; 292 293 bo->pages = drm_gem_get_pages(&bo->gem); 294 if (IS_ERR(bo->pages)) 295 return PTR_ERR(bo->pages); 296 297 bo->num_pages = bo->gem.size >> PAGE_SHIFT; 298 299 bo->sgt = drm_prime_pages_to_sg(bo->gem.dev, bo->pages, bo->num_pages); 300 if (IS_ERR(bo->sgt)) { 301 err = PTR_ERR(bo->sgt); 302 goto put_pages; 303 } 304 305 err = dma_map_sg(drm->dev, bo->sgt->sgl, bo->sgt->nents, 306 DMA_FROM_DEVICE); 307 if (err == 0) { 308 err = -EFAULT; 309 goto free_sgt; 310 } 311 312 return 0; 313 314 free_sgt: 315 sg_free_table(bo->sgt); 316 kfree(bo->sgt); 317 put_pages: 318 drm_gem_put_pages(&bo->gem, bo->pages, false, false); 319 return err; 320 } 321 322 static int tegra_bo_alloc(struct drm_device *drm, struct tegra_bo *bo) 323 { 324 struct tegra_drm *tegra = drm->dev_private; 325 int err; 326 327 if (tegra->domain) { 328 err = tegra_bo_get_pages(drm, bo); 329 if (err < 0) 330 return err; 331 332 err = tegra_bo_iommu_map(tegra, bo); 333 if (err < 0) { 334 tegra_bo_free(drm, bo); 335 return err; 336 } 337 } else { 338 size_t size = bo->gem.size; 339 340 bo->vaddr = dma_alloc_wc(drm->dev, size, &bo->iova, 341 GFP_KERNEL | __GFP_NOWARN); 342 if (!bo->vaddr) { 343 dev_err(drm->dev, 344 "failed to allocate buffer of size %zu\n", 345 size); 346 return -ENOMEM; 347 } 348 } 349 350 return 0; 351 } 352 353 struct tegra_bo *tegra_bo_create(struct drm_device *drm, size_t size, 354 unsigned long flags) 355 { 356 struct tegra_bo *bo; 357 int err; 358 359 bo = tegra_bo_alloc_object(drm, size); 360 if (IS_ERR(bo)) 361 return bo; 362 363 err = tegra_bo_alloc(drm, bo); 364 if (err < 0) 365 goto release; 366 367 if (flags & DRM_TEGRA_GEM_CREATE_TILED) 368 bo->tiling.mode = TEGRA_BO_TILING_MODE_TILED; 369 370 if (flags & DRM_TEGRA_GEM_CREATE_BOTTOM_UP) 371 bo->flags |= TEGRA_BO_BOTTOM_UP; 372 373 return bo; 374 375 release: 376 drm_gem_object_release(&bo->gem); 377 kfree(bo); 378 return ERR_PTR(err); 379 } 380 381 struct tegra_bo *tegra_bo_create_with_handle(struct drm_file *file, 382 struct drm_device *drm, 383 size_t size, 384 unsigned long flags, 385 u32 *handle) 386 { 387 struct tegra_bo *bo; 388 int err; 389 390 bo = tegra_bo_create(drm, size, flags); 391 if (IS_ERR(bo)) 392 return bo; 393 394 err = drm_gem_handle_create(file, &bo->gem, handle); 395 if (err) { 396 tegra_bo_free_object(&bo->gem); 397 return ERR_PTR(err); 398 } 399 400 drm_gem_object_put(&bo->gem); 401 402 return bo; 403 } 404 405 static struct tegra_bo *tegra_bo_import(struct drm_device *drm, 406 struct dma_buf *buf) 407 { 408 struct tegra_drm *tegra = drm->dev_private; 409 struct dma_buf_attachment *attach; 410 struct tegra_bo *bo; 411 int err; 412 413 bo = tegra_bo_alloc_object(drm, buf->size); 414 if (IS_ERR(bo)) 415 return bo; 416 417 attach = dma_buf_attach(buf, drm->dev); 418 if (IS_ERR(attach)) { 419 err = PTR_ERR(attach); 420 goto free; 421 } 422 423 get_dma_buf(buf); 424 425 bo->sgt = dma_buf_map_attachment(attach, DMA_TO_DEVICE); 426 if (IS_ERR(bo->sgt)) { 427 err = PTR_ERR(bo->sgt); 428 goto detach; 429 } 430 431 if (tegra->domain) { 432 err = tegra_bo_iommu_map(tegra, bo); 433 if (err < 0) 434 goto detach; 435 } 436 437 bo->gem.import_attach = attach; 438 439 return bo; 440 441 detach: 442 if (!IS_ERR_OR_NULL(bo->sgt)) 443 dma_buf_unmap_attachment(attach, bo->sgt, DMA_TO_DEVICE); 444 445 dma_buf_detach(buf, attach); 446 dma_buf_put(buf); 447 free: 448 drm_gem_object_release(&bo->gem); 449 kfree(bo); 450 return ERR_PTR(err); 451 } 452 453 void tegra_bo_free_object(struct drm_gem_object *gem) 454 { 455 struct tegra_drm *tegra = gem->dev->dev_private; 456 struct tegra_bo *bo = to_tegra_bo(gem); 457 458 if (tegra->domain) 459 tegra_bo_iommu_unmap(tegra, bo); 460 461 if (gem->import_attach) { 462 dma_buf_unmap_attachment(gem->import_attach, bo->sgt, 463 DMA_TO_DEVICE); 464 drm_prime_gem_destroy(gem, NULL); 465 } else { 466 tegra_bo_free(gem->dev, bo); 467 } 468 469 drm_gem_object_release(gem); 470 kfree(bo); 471 } 472 473 int tegra_bo_dumb_create(struct drm_file *file, struct drm_device *drm, 474 struct drm_mode_create_dumb *args) 475 { 476 unsigned int min_pitch = DIV_ROUND_UP(args->width * args->bpp, 8); 477 struct tegra_drm *tegra = drm->dev_private; 478 struct tegra_bo *bo; 479 480 args->pitch = round_up(min_pitch, tegra->pitch_align); 481 args->size = args->pitch * args->height; 482 483 bo = tegra_bo_create_with_handle(file, drm, args->size, 0, 484 &args->handle); 485 if (IS_ERR(bo)) 486 return PTR_ERR(bo); 487 488 return 0; 489 } 490 491 static vm_fault_t tegra_bo_fault(struct vm_fault *vmf) 492 { 493 struct vm_area_struct *vma = vmf->vma; 494 struct drm_gem_object *gem = vma->vm_private_data; 495 struct tegra_bo *bo = to_tegra_bo(gem); 496 struct page *page; 497 pgoff_t offset; 498 499 if (!bo->pages) 500 return VM_FAULT_SIGBUS; 501 502 offset = (vmf->address - vma->vm_start) >> PAGE_SHIFT; 503 page = bo->pages[offset]; 504 505 return vmf_insert_page(vma, vmf->address, page); 506 } 507 508 const struct vm_operations_struct tegra_bo_vm_ops = { 509 .fault = tegra_bo_fault, 510 .open = drm_gem_vm_open, 511 .close = drm_gem_vm_close, 512 }; 513 514 int __tegra_gem_mmap(struct drm_gem_object *gem, struct vm_area_struct *vma) 515 { 516 struct tegra_bo *bo = to_tegra_bo(gem); 517 518 if (!bo->pages) { 519 unsigned long vm_pgoff = vma->vm_pgoff; 520 int err; 521 522 /* 523 * Clear the VM_PFNMAP flag that was set by drm_gem_mmap(), 524 * and set the vm_pgoff (used as a fake buffer offset by DRM) 525 * to 0 as we want to map the whole buffer. 526 */ 527 vma->vm_flags &= ~VM_PFNMAP; 528 vma->vm_pgoff = 0; 529 530 err = dma_mmap_wc(gem->dev->dev, vma, bo->vaddr, bo->iova, 531 gem->size); 532 if (err < 0) { 533 drm_gem_vm_close(vma); 534 return err; 535 } 536 537 vma->vm_pgoff = vm_pgoff; 538 } else { 539 pgprot_t prot = vm_get_page_prot(vma->vm_flags); 540 541 vma->vm_flags |= VM_MIXEDMAP; 542 vma->vm_flags &= ~VM_PFNMAP; 543 544 vma->vm_page_prot = pgprot_writecombine(prot); 545 } 546 547 return 0; 548 } 549 550 int tegra_drm_mmap(struct file *file, struct vm_area_struct *vma) 551 { 552 struct drm_gem_object *gem; 553 int err; 554 555 err = drm_gem_mmap(file, vma); 556 if (err < 0) 557 return err; 558 559 gem = vma->vm_private_data; 560 561 return __tegra_gem_mmap(gem, vma); 562 } 563 564 static struct sg_table * 565 tegra_gem_prime_map_dma_buf(struct dma_buf_attachment *attach, 566 enum dma_data_direction dir) 567 { 568 struct drm_gem_object *gem = attach->dmabuf->priv; 569 struct tegra_bo *bo = to_tegra_bo(gem); 570 struct sg_table *sgt; 571 572 sgt = kmalloc(sizeof(*sgt), GFP_KERNEL); 573 if (!sgt) 574 return NULL; 575 576 if (bo->pages) { 577 if (sg_alloc_table_from_pages(sgt, bo->pages, bo->num_pages, 578 0, gem->size, GFP_KERNEL) < 0) 579 goto free; 580 } else { 581 if (dma_get_sgtable(attach->dev, sgt, bo->vaddr, bo->iova, 582 gem->size) < 0) 583 goto free; 584 } 585 586 if (dma_map_sg(attach->dev, sgt->sgl, sgt->nents, dir) == 0) 587 goto free; 588 589 return sgt; 590 591 free: 592 sg_free_table(sgt); 593 kfree(sgt); 594 return NULL; 595 } 596 597 static void tegra_gem_prime_unmap_dma_buf(struct dma_buf_attachment *attach, 598 struct sg_table *sgt, 599 enum dma_data_direction dir) 600 { 601 struct drm_gem_object *gem = attach->dmabuf->priv; 602 struct tegra_bo *bo = to_tegra_bo(gem); 603 604 if (bo->pages) 605 dma_unmap_sg(attach->dev, sgt->sgl, sgt->nents, dir); 606 607 sg_free_table(sgt); 608 kfree(sgt); 609 } 610 611 static void tegra_gem_prime_release(struct dma_buf *buf) 612 { 613 drm_gem_dmabuf_release(buf); 614 } 615 616 static int tegra_gem_prime_begin_cpu_access(struct dma_buf *buf, 617 enum dma_data_direction direction) 618 { 619 struct drm_gem_object *gem = buf->priv; 620 struct tegra_bo *bo = to_tegra_bo(gem); 621 struct drm_device *drm = gem->dev; 622 623 if (bo->pages) 624 dma_sync_sg_for_cpu(drm->dev, bo->sgt->sgl, bo->sgt->nents, 625 DMA_FROM_DEVICE); 626 627 return 0; 628 } 629 630 static int tegra_gem_prime_end_cpu_access(struct dma_buf *buf, 631 enum dma_data_direction direction) 632 { 633 struct drm_gem_object *gem = buf->priv; 634 struct tegra_bo *bo = to_tegra_bo(gem); 635 struct drm_device *drm = gem->dev; 636 637 if (bo->pages) 638 dma_sync_sg_for_device(drm->dev, bo->sgt->sgl, bo->sgt->nents, 639 DMA_TO_DEVICE); 640 641 return 0; 642 } 643 644 static int tegra_gem_prime_mmap(struct dma_buf *buf, struct vm_area_struct *vma) 645 { 646 struct drm_gem_object *gem = buf->priv; 647 int err; 648 649 err = drm_gem_mmap_obj(gem, gem->size, vma); 650 if (err < 0) 651 return err; 652 653 return __tegra_gem_mmap(gem, vma); 654 } 655 656 static int tegra_gem_prime_vmap(struct dma_buf *buf, struct dma_buf_map *map) 657 { 658 struct drm_gem_object *gem = buf->priv; 659 struct tegra_bo *bo = to_tegra_bo(gem); 660 661 dma_buf_map_set_vaddr(map, bo->vaddr); 662 663 return 0; 664 } 665 666 static void tegra_gem_prime_vunmap(struct dma_buf *buf, void *vaddr) 667 { 668 } 669 670 static const struct dma_buf_ops tegra_gem_prime_dmabuf_ops = { 671 .map_dma_buf = tegra_gem_prime_map_dma_buf, 672 .unmap_dma_buf = tegra_gem_prime_unmap_dma_buf, 673 .release = tegra_gem_prime_release, 674 .begin_cpu_access = tegra_gem_prime_begin_cpu_access, 675 .end_cpu_access = tegra_gem_prime_end_cpu_access, 676 .mmap = tegra_gem_prime_mmap, 677 .vmap = tegra_gem_prime_vmap, 678 .vunmap = tegra_gem_prime_vunmap, 679 }; 680 681 struct dma_buf *tegra_gem_prime_export(struct drm_gem_object *gem, 682 int flags) 683 { 684 DEFINE_DMA_BUF_EXPORT_INFO(exp_info); 685 686 exp_info.exp_name = KBUILD_MODNAME; 687 exp_info.owner = gem->dev->driver->fops->owner; 688 exp_info.ops = &tegra_gem_prime_dmabuf_ops; 689 exp_info.size = gem->size; 690 exp_info.flags = flags; 691 exp_info.priv = gem; 692 693 return drm_gem_dmabuf_export(gem->dev, &exp_info); 694 } 695 696 struct drm_gem_object *tegra_gem_prime_import(struct drm_device *drm, 697 struct dma_buf *buf) 698 { 699 struct tegra_bo *bo; 700 701 if (buf->ops == &tegra_gem_prime_dmabuf_ops) { 702 struct drm_gem_object *gem = buf->priv; 703 704 if (gem->dev == drm) { 705 drm_gem_object_get(gem); 706 return gem; 707 } 708 } 709 710 bo = tegra_bo_import(drm, buf); 711 if (IS_ERR(bo)) 712 return ERR_CAST(bo); 713 714 return &bo->gem; 715 } 716