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