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); 135 136 if (obj->vaddr) 137 return obj->vaddr; 138 else if (obj->gem.import_attach) 139 return dma_buf_vmap(obj->gem.import_attach->dmabuf); 140 else 141 return vmap(obj->pages, obj->num_pages, VM_MAP, 142 pgprot_writecombine(PAGE_KERNEL)); 143 } 144 145 static void tegra_bo_munmap(struct host1x_bo *bo, void *addr) 146 { 147 struct tegra_bo *obj = host1x_to_tegra_bo(bo); 148 149 if (obj->vaddr) 150 return; 151 else if (obj->gem.import_attach) 152 dma_buf_vunmap(obj->gem.import_attach->dmabuf, addr); 153 else 154 vunmap(addr); 155 } 156 157 static struct host1x_bo *tegra_bo_get(struct host1x_bo *bo) 158 { 159 struct tegra_bo *obj = host1x_to_tegra_bo(bo); 160 161 drm_gem_object_get(&obj->gem); 162 163 return bo; 164 } 165 166 static const struct host1x_bo_ops tegra_bo_ops = { 167 .get = tegra_bo_get, 168 .put = tegra_bo_put, 169 .pin = tegra_bo_pin, 170 .unpin = tegra_bo_unpin, 171 .mmap = tegra_bo_mmap, 172 .munmap = tegra_bo_munmap, 173 }; 174 175 static int tegra_bo_iommu_map(struct tegra_drm *tegra, struct tegra_bo *bo) 176 { 177 int prot = IOMMU_READ | IOMMU_WRITE; 178 int err; 179 180 if (bo->mm) 181 return -EBUSY; 182 183 bo->mm = kzalloc(sizeof(*bo->mm), GFP_KERNEL); 184 if (!bo->mm) 185 return -ENOMEM; 186 187 mutex_lock(&tegra->mm_lock); 188 189 err = drm_mm_insert_node_generic(&tegra->mm, 190 bo->mm, bo->gem.size, PAGE_SIZE, 0, 0); 191 if (err < 0) { 192 dev_err(tegra->drm->dev, "out of I/O virtual memory: %d\n", 193 err); 194 goto unlock; 195 } 196 197 bo->iova = bo->mm->start; 198 199 bo->size = iommu_map_sg(tegra->domain, bo->iova, bo->sgt->sgl, 200 bo->sgt->nents, prot); 201 if (!bo->size) { 202 dev_err(tegra->drm->dev, "failed to map buffer\n"); 203 err = -ENOMEM; 204 goto remove; 205 } 206 207 mutex_unlock(&tegra->mm_lock); 208 209 return 0; 210 211 remove: 212 drm_mm_remove_node(bo->mm); 213 unlock: 214 mutex_unlock(&tegra->mm_lock); 215 kfree(bo->mm); 216 return err; 217 } 218 219 static int tegra_bo_iommu_unmap(struct tegra_drm *tegra, struct tegra_bo *bo) 220 { 221 if (!bo->mm) 222 return 0; 223 224 mutex_lock(&tegra->mm_lock); 225 iommu_unmap(tegra->domain, bo->iova, bo->size); 226 drm_mm_remove_node(bo->mm); 227 mutex_unlock(&tegra->mm_lock); 228 229 kfree(bo->mm); 230 231 return 0; 232 } 233 234 static const struct drm_gem_object_funcs tegra_gem_object_funcs = { 235 .free = tegra_bo_free_object, 236 .export = tegra_gem_prime_export, 237 .vm_ops = &tegra_bo_vm_ops, 238 }; 239 240 static struct tegra_bo *tegra_bo_alloc_object(struct drm_device *drm, 241 size_t size) 242 { 243 struct tegra_bo *bo; 244 int err; 245 246 bo = kzalloc(sizeof(*bo), GFP_KERNEL); 247 if (!bo) 248 return ERR_PTR(-ENOMEM); 249 250 bo->gem.funcs = &tegra_gem_object_funcs; 251 252 host1x_bo_init(&bo->base, &tegra_bo_ops); 253 size = round_up(size, PAGE_SIZE); 254 255 err = drm_gem_object_init(drm, &bo->gem, size); 256 if (err < 0) 257 goto free; 258 259 err = drm_gem_create_mmap_offset(&bo->gem); 260 if (err < 0) 261 goto release; 262 263 return bo; 264 265 release: 266 drm_gem_object_release(&bo->gem); 267 free: 268 kfree(bo); 269 return ERR_PTR(err); 270 } 271 272 static void tegra_bo_free(struct drm_device *drm, struct tegra_bo *bo) 273 { 274 if (bo->pages) { 275 dma_unmap_sg(drm->dev, bo->sgt->sgl, bo->sgt->nents, 276 DMA_FROM_DEVICE); 277 drm_gem_put_pages(&bo->gem, bo->pages, true, true); 278 sg_free_table(bo->sgt); 279 kfree(bo->sgt); 280 } else if (bo->vaddr) { 281 dma_free_wc(drm->dev, bo->gem.size, bo->vaddr, bo->iova); 282 } 283 } 284 285 static int tegra_bo_get_pages(struct drm_device *drm, struct tegra_bo *bo) 286 { 287 int err; 288 289 bo->pages = drm_gem_get_pages(&bo->gem); 290 if (IS_ERR(bo->pages)) 291 return PTR_ERR(bo->pages); 292 293 bo->num_pages = bo->gem.size >> PAGE_SHIFT; 294 295 bo->sgt = drm_prime_pages_to_sg(bo->gem.dev, bo->pages, bo->num_pages); 296 if (IS_ERR(bo->sgt)) { 297 err = PTR_ERR(bo->sgt); 298 goto put_pages; 299 } 300 301 err = dma_map_sg(drm->dev, bo->sgt->sgl, bo->sgt->nents, 302 DMA_FROM_DEVICE); 303 if (err == 0) { 304 err = -EFAULT; 305 goto free_sgt; 306 } 307 308 return 0; 309 310 free_sgt: 311 sg_free_table(bo->sgt); 312 kfree(bo->sgt); 313 put_pages: 314 drm_gem_put_pages(&bo->gem, bo->pages, false, false); 315 return err; 316 } 317 318 static int tegra_bo_alloc(struct drm_device *drm, struct tegra_bo *bo) 319 { 320 struct tegra_drm *tegra = drm->dev_private; 321 int err; 322 323 if (tegra->domain) { 324 err = tegra_bo_get_pages(drm, bo); 325 if (err < 0) 326 return err; 327 328 err = tegra_bo_iommu_map(tegra, bo); 329 if (err < 0) { 330 tegra_bo_free(drm, bo); 331 return err; 332 } 333 } else { 334 size_t size = bo->gem.size; 335 336 bo->vaddr = dma_alloc_wc(drm->dev, size, &bo->iova, 337 GFP_KERNEL | __GFP_NOWARN); 338 if (!bo->vaddr) { 339 dev_err(drm->dev, 340 "failed to allocate buffer of size %zu\n", 341 size); 342 return -ENOMEM; 343 } 344 } 345 346 return 0; 347 } 348 349 struct tegra_bo *tegra_bo_create(struct drm_device *drm, size_t size, 350 unsigned long flags) 351 { 352 struct tegra_bo *bo; 353 int err; 354 355 bo = tegra_bo_alloc_object(drm, size); 356 if (IS_ERR(bo)) 357 return bo; 358 359 err = tegra_bo_alloc(drm, bo); 360 if (err < 0) 361 goto release; 362 363 if (flags & DRM_TEGRA_GEM_CREATE_TILED) 364 bo->tiling.mode = TEGRA_BO_TILING_MODE_TILED; 365 366 if (flags & DRM_TEGRA_GEM_CREATE_BOTTOM_UP) 367 bo->flags |= TEGRA_BO_BOTTOM_UP; 368 369 return bo; 370 371 release: 372 drm_gem_object_release(&bo->gem); 373 kfree(bo); 374 return ERR_PTR(err); 375 } 376 377 struct tegra_bo *tegra_bo_create_with_handle(struct drm_file *file, 378 struct drm_device *drm, 379 size_t size, 380 unsigned long flags, 381 u32 *handle) 382 { 383 struct tegra_bo *bo; 384 int err; 385 386 bo = tegra_bo_create(drm, size, flags); 387 if (IS_ERR(bo)) 388 return bo; 389 390 err = drm_gem_handle_create(file, &bo->gem, handle); 391 if (err) { 392 tegra_bo_free_object(&bo->gem); 393 return ERR_PTR(err); 394 } 395 396 drm_gem_object_put(&bo->gem); 397 398 return bo; 399 } 400 401 static struct tegra_bo *tegra_bo_import(struct drm_device *drm, 402 struct dma_buf *buf) 403 { 404 struct tegra_drm *tegra = drm->dev_private; 405 struct dma_buf_attachment *attach; 406 struct tegra_bo *bo; 407 int err; 408 409 bo = tegra_bo_alloc_object(drm, buf->size); 410 if (IS_ERR(bo)) 411 return bo; 412 413 attach = dma_buf_attach(buf, drm->dev); 414 if (IS_ERR(attach)) { 415 err = PTR_ERR(attach); 416 goto free; 417 } 418 419 get_dma_buf(buf); 420 421 bo->sgt = dma_buf_map_attachment(attach, DMA_TO_DEVICE); 422 if (IS_ERR(bo->sgt)) { 423 err = PTR_ERR(bo->sgt); 424 goto detach; 425 } 426 427 if (tegra->domain) { 428 err = tegra_bo_iommu_map(tegra, bo); 429 if (err < 0) 430 goto detach; 431 } 432 433 bo->gem.import_attach = attach; 434 435 return bo; 436 437 detach: 438 if (!IS_ERR_OR_NULL(bo->sgt)) 439 dma_buf_unmap_attachment(attach, bo->sgt, DMA_TO_DEVICE); 440 441 dma_buf_detach(buf, attach); 442 dma_buf_put(buf); 443 free: 444 drm_gem_object_release(&bo->gem); 445 kfree(bo); 446 return ERR_PTR(err); 447 } 448 449 void tegra_bo_free_object(struct drm_gem_object *gem) 450 { 451 struct tegra_drm *tegra = gem->dev->dev_private; 452 struct tegra_bo *bo = to_tegra_bo(gem); 453 454 if (tegra->domain) 455 tegra_bo_iommu_unmap(tegra, bo); 456 457 if (gem->import_attach) { 458 dma_buf_unmap_attachment(gem->import_attach, bo->sgt, 459 DMA_TO_DEVICE); 460 drm_prime_gem_destroy(gem, NULL); 461 } else { 462 tegra_bo_free(gem->dev, bo); 463 } 464 465 drm_gem_object_release(gem); 466 kfree(bo); 467 } 468 469 int tegra_bo_dumb_create(struct drm_file *file, struct drm_device *drm, 470 struct drm_mode_create_dumb *args) 471 { 472 unsigned int min_pitch = DIV_ROUND_UP(args->width * args->bpp, 8); 473 struct tegra_drm *tegra = drm->dev_private; 474 struct tegra_bo *bo; 475 476 args->pitch = round_up(min_pitch, tegra->pitch_align); 477 args->size = args->pitch * args->height; 478 479 bo = tegra_bo_create_with_handle(file, drm, args->size, 0, 480 &args->handle); 481 if (IS_ERR(bo)) 482 return PTR_ERR(bo); 483 484 return 0; 485 } 486 487 static vm_fault_t tegra_bo_fault(struct vm_fault *vmf) 488 { 489 struct vm_area_struct *vma = vmf->vma; 490 struct drm_gem_object *gem = vma->vm_private_data; 491 struct tegra_bo *bo = to_tegra_bo(gem); 492 struct page *page; 493 pgoff_t offset; 494 495 if (!bo->pages) 496 return VM_FAULT_SIGBUS; 497 498 offset = (vmf->address - vma->vm_start) >> PAGE_SHIFT; 499 page = bo->pages[offset]; 500 501 return vmf_insert_page(vma, vmf->address, page); 502 } 503 504 const struct vm_operations_struct tegra_bo_vm_ops = { 505 .fault = tegra_bo_fault, 506 .open = drm_gem_vm_open, 507 .close = drm_gem_vm_close, 508 }; 509 510 int __tegra_gem_mmap(struct drm_gem_object *gem, struct vm_area_struct *vma) 511 { 512 struct tegra_bo *bo = to_tegra_bo(gem); 513 514 if (!bo->pages) { 515 unsigned long vm_pgoff = vma->vm_pgoff; 516 int err; 517 518 /* 519 * Clear the VM_PFNMAP flag that was set by drm_gem_mmap(), 520 * and set the vm_pgoff (used as a fake buffer offset by DRM) 521 * to 0 as we want to map the whole buffer. 522 */ 523 vma->vm_flags &= ~VM_PFNMAP; 524 vma->vm_pgoff = 0; 525 526 err = dma_mmap_wc(gem->dev->dev, vma, bo->vaddr, bo->iova, 527 gem->size); 528 if (err < 0) { 529 drm_gem_vm_close(vma); 530 return err; 531 } 532 533 vma->vm_pgoff = vm_pgoff; 534 } else { 535 pgprot_t prot = vm_get_page_prot(vma->vm_flags); 536 537 vma->vm_flags |= VM_MIXEDMAP; 538 vma->vm_flags &= ~VM_PFNMAP; 539 540 vma->vm_page_prot = pgprot_writecombine(prot); 541 } 542 543 return 0; 544 } 545 546 int tegra_drm_mmap(struct file *file, struct vm_area_struct *vma) 547 { 548 struct drm_gem_object *gem; 549 int err; 550 551 err = drm_gem_mmap(file, vma); 552 if (err < 0) 553 return err; 554 555 gem = vma->vm_private_data; 556 557 return __tegra_gem_mmap(gem, vma); 558 } 559 560 static struct sg_table * 561 tegra_gem_prime_map_dma_buf(struct dma_buf_attachment *attach, 562 enum dma_data_direction dir) 563 { 564 struct drm_gem_object *gem = attach->dmabuf->priv; 565 struct tegra_bo *bo = to_tegra_bo(gem); 566 struct sg_table *sgt; 567 568 sgt = kmalloc(sizeof(*sgt), GFP_KERNEL); 569 if (!sgt) 570 return NULL; 571 572 if (bo->pages) { 573 if (sg_alloc_table_from_pages(sgt, bo->pages, bo->num_pages, 574 0, gem->size, GFP_KERNEL) < 0) 575 goto free; 576 } else { 577 if (dma_get_sgtable(attach->dev, sgt, bo->vaddr, bo->iova, 578 gem->size) < 0) 579 goto free; 580 } 581 582 if (dma_map_sg(attach->dev, sgt->sgl, sgt->nents, dir) == 0) 583 goto free; 584 585 return sgt; 586 587 free: 588 sg_free_table(sgt); 589 kfree(sgt); 590 return NULL; 591 } 592 593 static void tegra_gem_prime_unmap_dma_buf(struct dma_buf_attachment *attach, 594 struct sg_table *sgt, 595 enum dma_data_direction dir) 596 { 597 struct drm_gem_object *gem = attach->dmabuf->priv; 598 struct tegra_bo *bo = to_tegra_bo(gem); 599 600 if (bo->pages) 601 dma_unmap_sg(attach->dev, sgt->sgl, sgt->nents, dir); 602 603 sg_free_table(sgt); 604 kfree(sgt); 605 } 606 607 static void tegra_gem_prime_release(struct dma_buf *buf) 608 { 609 drm_gem_dmabuf_release(buf); 610 } 611 612 static int tegra_gem_prime_begin_cpu_access(struct dma_buf *buf, 613 enum dma_data_direction direction) 614 { 615 struct drm_gem_object *gem = buf->priv; 616 struct tegra_bo *bo = to_tegra_bo(gem); 617 struct drm_device *drm = gem->dev; 618 619 if (bo->pages) 620 dma_sync_sg_for_cpu(drm->dev, bo->sgt->sgl, bo->sgt->nents, 621 DMA_FROM_DEVICE); 622 623 return 0; 624 } 625 626 static int tegra_gem_prime_end_cpu_access(struct dma_buf *buf, 627 enum dma_data_direction direction) 628 { 629 struct drm_gem_object *gem = buf->priv; 630 struct tegra_bo *bo = to_tegra_bo(gem); 631 struct drm_device *drm = gem->dev; 632 633 if (bo->pages) 634 dma_sync_sg_for_device(drm->dev, bo->sgt->sgl, bo->sgt->nents, 635 DMA_TO_DEVICE); 636 637 return 0; 638 } 639 640 static int tegra_gem_prime_mmap(struct dma_buf *buf, struct vm_area_struct *vma) 641 { 642 struct drm_gem_object *gem = buf->priv; 643 int err; 644 645 err = drm_gem_mmap_obj(gem, gem->size, vma); 646 if (err < 0) 647 return err; 648 649 return __tegra_gem_mmap(gem, vma); 650 } 651 652 static void *tegra_gem_prime_vmap(struct dma_buf *buf) 653 { 654 struct drm_gem_object *gem = buf->priv; 655 struct tegra_bo *bo = to_tegra_bo(gem); 656 657 return bo->vaddr; 658 } 659 660 static void tegra_gem_prime_vunmap(struct dma_buf *buf, void *vaddr) 661 { 662 } 663 664 static const struct dma_buf_ops tegra_gem_prime_dmabuf_ops = { 665 .map_dma_buf = tegra_gem_prime_map_dma_buf, 666 .unmap_dma_buf = tegra_gem_prime_unmap_dma_buf, 667 .release = tegra_gem_prime_release, 668 .begin_cpu_access = tegra_gem_prime_begin_cpu_access, 669 .end_cpu_access = tegra_gem_prime_end_cpu_access, 670 .mmap = tegra_gem_prime_mmap, 671 .vmap = tegra_gem_prime_vmap, 672 .vunmap = tegra_gem_prime_vunmap, 673 }; 674 675 struct dma_buf *tegra_gem_prime_export(struct drm_gem_object *gem, 676 int flags) 677 { 678 DEFINE_DMA_BUF_EXPORT_INFO(exp_info); 679 680 exp_info.exp_name = KBUILD_MODNAME; 681 exp_info.owner = gem->dev->driver->fops->owner; 682 exp_info.ops = &tegra_gem_prime_dmabuf_ops; 683 exp_info.size = gem->size; 684 exp_info.flags = flags; 685 exp_info.priv = gem; 686 687 return drm_gem_dmabuf_export(gem->dev, &exp_info); 688 } 689 690 struct drm_gem_object *tegra_gem_prime_import(struct drm_device *drm, 691 struct dma_buf *buf) 692 { 693 struct tegra_bo *bo; 694 695 if (buf->ops == &tegra_gem_prime_dmabuf_ops) { 696 struct drm_gem_object *gem = buf->priv; 697 698 if (gem->dev == drm) { 699 drm_gem_object_get(gem); 700 return gem; 701 } 702 } 703 704 bo = tegra_bo_import(drm, buf); 705 if (IS_ERR(bo)) 706 return ERR_CAST(bo); 707 708 return &bo->gem; 709 } 710