nouveau_bo.c

		ret = nouveau_bo_move_m2mf(bo, evict, ctx,
					   new_reg);
	} else
		ret = -ENODEV;

	if (ret) {
		/* Fallback to software copy. */
		ret = ttm_bo_move_memcpy(bo, ctx, new_reg);
	}

out:
	if (drm->client.device.info.family < NV_DEVICE_INFO_V0_TESLA) {
		if (ret)
			nouveau_bo_vm_cleanup(bo, NULL, &new_tile);
		else
			nouveau_bo_vm_cleanup(bo, new_tile, &nvbo->tile);
	}
out_ntfy:
	if (ret) {
		swap(*new_reg, bo->mem);
		nouveau_bo_move_ntfy(bo, false, new_reg);
		swap(*new_reg, bo->mem);
	}
	return ret;
}

static int
nouveau_bo_verify_access(struct ttm_buffer_object *bo, struct file *filp)
{
	struct nouveau_bo *nvbo = nouveau_bo(bo);

	return drm_vma_node_verify_access(&nvbo->bo.base.vma_node,
					  filp->private_data);
}

static void
nouveau_ttm_io_mem_free_locked(struct nouveau_drm *drm,
			       struct ttm_resource *reg)
{
	struct nouveau_mem *mem = nouveau_mem(reg);

	if (drm->client.mem->oclass >= NVIF_CLASS_MEM_NV50) {
		switch (reg->mem_type) {
		case TTM_PL_TT:
			if (mem->kind)
				nvif_object_unmap_handle(&mem->mem.object);
			break;
		case TTM_PL_VRAM:
			nvif_object_unmap_handle(&mem->mem.object);
			break;
		default:
			break;
		}
	}
}

static int
nouveau_ttm_io_mem_reserve(struct ttm_bo_device *bdev, struct ttm_resource *reg)
{
	struct nouveau_drm *drm = nouveau_bdev(bdev);
	struct nvkm_device *device = nvxx_device(&drm->client.device);
	struct nouveau_mem *mem = nouveau_mem(reg);
	struct nvif_mmu *mmu = &drm->client.mmu;
	int ret;

	mutex_lock(&drm->ttm.io_reserve_mutex);
retry:
	switch (reg->mem_type) {
	case TTM_PL_SYSTEM:
		/* System memory */
		ret = 0;
		goto out;
	case TTM_PL_TT:
#if IS_ENABLED(CONFIG_AGP)
		if (drm->agp.bridge) {
			reg->bus.offset = (reg->start << PAGE_SHIFT) +
				drm->agp.base;
			reg->bus.is_iomem = !drm->agp.cma;
			reg->bus.caching = ttm_write_combined;
		}
#endif
		if (drm->client.mem->oclass < NVIF_CLASS_MEM_NV50 ||
		    !mem->kind) {
			/* untiled */
			ret = 0;
			break;
		}
		fallthrough;	/* tiled memory */
	case TTM_PL_VRAM:
		reg->bus.offset = (reg->start << PAGE_SHIFT) +
			device->func->resource_addr(device, 1);
		reg->bus.is_iomem = true;

		/* Some BARs do not support being ioremapped WC */
		if (drm->client.device.info.family >= NV_DEVICE_INFO_V0_TESLA &&
		    mmu->type[drm->ttm.type_vram].type & NVIF_MEM_UNCACHED)
			reg->bus.caching = ttm_uncached;
		else
			reg->bus.caching = ttm_write_combined;

		if (drm->client.mem->oclass >= NVIF_CLASS_MEM_NV50) {
			union {
				struct nv50_mem_map_v0 nv50;
				struct gf100_mem_map_v0 gf100;
			} args;
			u64 handle, length;
			u32 argc = 0;

			switch (mem->mem.object.oclass) {
			case NVIF_CLASS_MEM_NV50:
				args.nv50.version = 0;
				args.nv50.ro = 0;
				args.nv50.kind = mem->kind;
				args.nv50.comp = mem->comp;
				argc = sizeof(args.nv50);
				break;
			case NVIF_CLASS_MEM_GF100:
				args.gf100.version = 0;
				args.gf100.ro = 0;
				args.gf100.kind = mem->kind;
				argc = sizeof(args.gf100);
				break;
			default:
				WARN_ON(1);
				break;
			}

			ret = nvif_object_map_handle(&mem->mem.object,
						     &args, argc,
						     &handle, &length);
			if (ret != 1) {
				if (WARN_ON(ret == 0))
					ret = -EINVAL;
				goto out;
			}

			reg->bus.offset = handle;
		}
		ret = 0;
		break;
	default:
		ret = -EINVAL;
	}

out:
	if (ret == -ENOSPC) {
		struct nouveau_bo *nvbo;

		nvbo = list_first_entry_or_null(&drm->ttm.io_reserve_lru,
						typeof(*nvbo),
						io_reserve_lru);
		if (nvbo) {
			list_del_init(&nvbo->io_reserve_lru);
			drm_vma_node_unmap(&nvbo->bo.base.vma_node,
					   bdev->dev_mapping);
			nouveau_ttm_io_mem_free_locked(drm, &nvbo->bo.mem);
			goto retry;
		}

	}
	mutex_unlock(&drm->ttm.io_reserve_mutex);
	return ret;
}

static void
nouveau_ttm_io_mem_free(struct ttm_bo_device *bdev, struct ttm_resource *reg)
{
	struct nouveau_drm *drm = nouveau_bdev(bdev);

	mutex_lock(&drm->ttm.io_reserve_mutex);
	nouveau_ttm_io_mem_free_locked(drm, reg);
	mutex_unlock(&drm->ttm.io_reserve_mutex);
}

vm_fault_t nouveau_ttm_fault_reserve_notify(struct ttm_buffer_object *bo)
{
	struct nouveau_drm *drm = nouveau_bdev(bo->bdev);
	struct nouveau_bo *nvbo = nouveau_bo(bo);
	struct nvkm_device *device = nvxx_device(&drm->client.device);
	u32 mappable = device->func->resource_size(device, 1) >> PAGE_SHIFT;
	int i, ret;

	/* as long as the bo isn't in vram, and isn't tiled, we've got
	 * nothing to do here.
	 */
	if (bo->mem.mem_type != TTM_PL_VRAM) {
		if (drm->client.device.info.family < NV_DEVICE_INFO_V0_TESLA ||
		    !nvbo->kind)
			return 0;

		if (bo->mem.mem_type != TTM_PL_SYSTEM)
			return 0;

		nouveau_bo_placement_set(nvbo, NOUVEAU_GEM_DOMAIN_GART, 0);

	} else {
		/* make sure bo is in mappable vram */
		if (drm->client.device.info.family >= NV_DEVICE_INFO_V0_TESLA ||
		    bo->mem.start + bo->mem.num_pages < mappable)
			return 0;

		for (i = 0; i < nvbo->placement.num_placement; ++i) {
			nvbo->placements[i].fpfn = 0;
			nvbo->placements[i].lpfn = mappable;
		}

		for (i = 0; i < nvbo->placement.num_busy_placement; ++i) {
			nvbo->busy_placements[i].fpfn = 0;
			nvbo->busy_placements[i].lpfn = mappable;
		}

		nouveau_bo_placement_set(nvbo, NOUVEAU_GEM_DOMAIN_VRAM, 0);
	}

	ret = nouveau_bo_validate(nvbo, false, false);
	if (unlikely(ret == -EBUSY || ret == -ERESTARTSYS))
		return VM_FAULT_NOPAGE;
	else if (unlikely(ret))
		return VM_FAULT_SIGBUS;

	ttm_bo_move_to_lru_tail_unlocked(bo);
	return 0;
}

static int
nouveau_ttm_tt_populate(struct ttm_bo_device *bdev,
			struct ttm_tt *ttm, struct ttm_operation_ctx *ctx)
{
	struct ttm_tt *ttm_dma = (void *)ttm;
	struct nouveau_drm *drm;
	struct device *dev;
	bool slave = !!(ttm->page_flags & TTM_PAGE_FLAG_SG);

	if (ttm_tt_is_populated(ttm))
		return 0;

	if (slave && ttm->sg) {
		drm_prime_sg_to_dma_addr_array(ttm->sg, ttm_dma->dma_address,
					       ttm->num_pages);
		return 0;
	}

	drm = nouveau_bdev(bdev);
	dev = drm->dev->dev;

	return ttm_pool_alloc(&drm->ttm.bdev.pool, ttm, ctx);
}

static void
nouveau_ttm_tt_unpopulate(struct ttm_bo_device *bdev,
			  struct ttm_tt *ttm)
{
	struct nouveau_drm *drm;
	struct device *dev;
	bool slave = !!(ttm->page_flags & TTM_PAGE_FLAG_SG);

	if (slave)
		return;

	drm = nouveau_bdev(bdev);
	dev = drm->dev->dev;

	return ttm_pool_free(&drm->ttm.bdev.pool, ttm);
}

static void
nouveau_ttm_tt_destroy(struct ttm_bo_device *bdev,
		       struct ttm_tt *ttm)
{
#if IS_ENABLED(CONFIG_AGP)
	struct nouveau_drm *drm = nouveau_bdev(bdev);
	if (drm->agp.bridge) {
		ttm_agp_unbind(ttm);
		ttm_tt_destroy_common(bdev, ttm);
		ttm_agp_destroy(ttm);
		return;
	}
#endif
	nouveau_sgdma_destroy(bdev, ttm);
}

void
nouveau_bo_fence(struct nouveau_bo *nvbo, struct nouveau_fence *fence, bool exclusive)
{
	struct dma_resv *resv = nvbo->bo.base.resv;

	if (exclusive)
		dma_resv_add_excl_fence(resv, &fence->base);
	else if (fence)
		dma_resv_add_shared_fence(resv, &fence->base);
}

static void
nouveau_bo_delete_mem_notify(struct ttm_buffer_object *bo)
{
	nouveau_bo_move_ntfy(bo, false, NULL);
}

struct ttm_bo_driver nouveau_bo_driver = {
	.ttm_tt_create = &nouveau_ttm_tt_create,
	.ttm_tt_populate = &nouveau_ttm_tt_populate,
	.ttm_tt_unpopulate = &nouveau_ttm_tt_unpopulate,
	.ttm_tt_destroy = &nouveau_ttm_tt_destroy,
	.eviction_valuable = ttm_bo_eviction_valuable,
	.evict_flags = nouveau_bo_evict_flags,
	.delete_mem_notify = nouveau_bo_delete_mem_notify,
	.move = nouveau_bo_move,
	.verify_access = nouveau_bo_verify_access,
	.io_mem_reserve = &nouveau_ttm_io_mem_reserve,
	.io_mem_free = &nouveau_ttm_io_mem_free,
};