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