1 // SPDX-License-Identifier: GPL-2.0-or-later
12 #include <linux/dma-buf.h>
13 #include <linux/dma-mapping.h>
46  * __drm_gem_cma_create - Create a GEM CMA object without allocating memory
55  * A struct drm_gem_cma_object * on success or an ERR_PTR()-encoded negative
65 	if (drm->driver->gem_create_object)  in __drm_gem_cma_create()
66 		gem_obj = drm->driver->gem_create_object(drm, size);  in __drm_gem_cma_create()
70 		return ERR_PTR(-ENOMEM);  in __drm_gem_cma_create()
72 	if (!gem_obj->funcs)  in __drm_gem_cma_create()
73 		gem_obj->funcs = &drm_gem_cma_default_funcs;  in __drm_gem_cma_create()
80 		/* Always use writecombine for dma-buf mappings */  in __drm_gem_cma_create()
81 		cma_obj->map_noncoherent = false;  in __drm_gem_cma_create()
102  * drm_gem_cma_create - allocate an object with the given size
110  * A struct drm_gem_cma_object * on success or an ERR_PTR()-encoded negative
125 	if (cma_obj->map_noncoherent) {  in drm_gem_cma_create()
126 		cma_obj->vaddr = dma_alloc_noncoherent(drm->dev, size,  in drm_gem_cma_create()
127 						       &cma_obj->paddr,  in drm_gem_cma_create()
131 		cma_obj->vaddr = dma_alloc_wc(drm->dev, size, &cma_obj->paddr,  in drm_gem_cma_create()
134 	if (!cma_obj->vaddr) {  in drm_gem_cma_create()
137 		ret = -ENOMEM;  in drm_gem_cma_create()
144 	drm_gem_object_put(&cma_obj->base);  in drm_gem_cma_create()
150  * drm_gem_cma_create_with_handle - allocate an object with the given size and
152  * @file_priv: DRM file-private structure to register the handle for
162  * A struct drm_gem_cma_object * on success or an ERR_PTR()-encoded negative
178 	gem_obj = &cma_obj->base;  in drm_gem_cma_create_with_handle()
185 	/* drop reference from allocate - handle holds it now. */  in drm_gem_cma_create_with_handle()
194  * drm_gem_cma_free_object - free resources associated with a CMA GEM object
206 	struct dma_buf_map map = DMA_BUF_MAP_INIT_VADDR(cma_obj->vaddr);  in drm_gem_cma_free_object()
208 	if (gem_obj->import_attach) {  in drm_gem_cma_free_object()
209 		if (cma_obj->vaddr)  in drm_gem_cma_free_object()
210 			dma_buf_vunmap(gem_obj->import_attach->dmabuf, &map);  in drm_gem_cma_free_object()
211 		drm_prime_gem_destroy(gem_obj, cma_obj->sgt);  in drm_gem_cma_free_object()
212 	} else if (cma_obj->vaddr) {  in drm_gem_cma_free_object()
213 		dma_free_wc(gem_obj->dev->dev, cma_obj->base.size,  in drm_gem_cma_free_object()
214 			    cma_obj->vaddr, cma_obj->paddr);  in drm_gem_cma_free_object()
224  * drm_gem_cma_dumb_create_internal - create a dumb buffer object
225  * @file_priv: DRM file-private structure to create the dumb buffer for
241 	unsigned int min_pitch = DIV_ROUND_UP(args->width * args->bpp, 8);  in drm_gem_cma_dumb_create_internal()
244 	if (args->pitch < min_pitch)  in drm_gem_cma_dumb_create_internal()
245 		args->pitch = min_pitch;  in drm_gem_cma_dumb_create_internal()
247 	if (args->size < args->pitch * args->height)  in drm_gem_cma_dumb_create_internal()
248 		args->size = args->pitch * args->height;  in drm_gem_cma_dumb_create_internal()
250 	cma_obj = drm_gem_cma_create_with_handle(file_priv, drm, args->size,  in drm_gem_cma_dumb_create_internal()
251 						 &args->handle);  in drm_gem_cma_dumb_create_internal()
257  * drm_gem_cma_dumb_create - create a dumb buffer object
258  * @file_priv: DRM file-private structure to create the dumb buffer for
280 	args->pitch = DIV_ROUND_UP(args->width * args->bpp, 8);  in drm_gem_cma_dumb_create()
281 	args->size = args->pitch * args->height;  in drm_gem_cma_dumb_create()
283 	cma_obj = drm_gem_cma_create_with_handle(file_priv, drm, args->size,  in drm_gem_cma_dumb_create()
284 						 &args->handle);  in drm_gem_cma_dumb_create()
297  * drm_gem_cma_get_unmapped_area - propose address for mapping in noMMU cases
320 	struct drm_file *priv = filp->private_data;  in drm_gem_cma_get_unmapped_area()
321 	struct drm_device *dev = priv->minor->dev;  in drm_gem_cma_get_unmapped_area()
325 		return -ENODEV;  in drm_gem_cma_get_unmapped_area()
327 	drm_vma_offset_lock_lookup(dev->vma_offset_manager);  in drm_gem_cma_get_unmapped_area()
328 	node = drm_vma_offset_exact_lookup_locked(dev->vma_offset_manager,  in drm_gem_cma_get_unmapped_area()
334 		 * When the object is being freed, after it hits 0-refcnt it  in drm_gem_cma_get_unmapped_area()
337 		 * mgr->vm_lock.  Therefore if we find an object with a 0-refcnt  in drm_gem_cma_get_unmapped_area()
339 		 * destroyed and will be freed as soon as we release the lock -  in drm_gem_cma_get_unmapped_area()
340 		 * so we have to check for the 0-refcnted object and treat it as  in drm_gem_cma_get_unmapped_area()
343 		if (!kref_get_unless_zero(&obj->refcount))  in drm_gem_cma_get_unmapped_area()
347 	drm_vma_offset_unlock_lookup(dev->vma_offset_manager);  in drm_gem_cma_get_unmapped_area()
350 		return -EINVAL;  in drm_gem_cma_get_unmapped_area()
354 		return -EACCES;  in drm_gem_cma_get_unmapped_area()
361 	return cma_obj->vaddr ? (unsigned long)cma_obj->vaddr : -EINVAL;  in drm_gem_cma_get_unmapped_area()
367  * drm_gem_cma_print_info() - Print &drm_gem_cma_object info for debugfs
372  * This function can be used as the &drm_driver->gem_print_info callback.
380 	drm_printf_indent(p, indent, "paddr=%pad\n", &cma_obj->paddr);  in drm_gem_cma_print_info()
381 	drm_printf_indent(p, indent, "vaddr=%p\n", cma_obj->vaddr);  in drm_gem_cma_print_info()
386  * drm_gem_cma_get_sg_table - provide a scatter/gather table of pinned
390  * This function exports a scatter/gather table by
395  * A pointer to the scatter/gather table of pinned pages or NULL on failure.
405 		return ERR_PTR(-ENOMEM);  in drm_gem_cma_get_sg_table()
407 	ret = dma_get_sgtable(obj->dev->dev, sgt, cma_obj->vaddr,  in drm_gem_cma_get_sg_table()
408 			      cma_obj->paddr, obj->size);  in drm_gem_cma_get_sg_table()
421  * drm_gem_cma_prime_import_sg_table - produce a CMA GEM object from another
422  *     driver's scatter/gather table of pinned pages
424  * @attach: DMA-BUF attachment
425  * @sgt: scatter/gather table of pinned pages
427  * This function imports a scatter/gather table exported via DMA-BUF by
429  * (i.e. the scatter/gather table must contain a single entry). Drivers that
434  * A pointer to a newly created GEM object or an ERR_PTR-encoded negative
445 	if (drm_prime_get_contiguous_size(sgt) < attach->dmabuf->size)  in drm_gem_cma_prime_import_sg_table()
446 		return ERR_PTR(-EINVAL);  in drm_gem_cma_prime_import_sg_table()
449 	cma_obj = __drm_gem_cma_create(dev, attach->dmabuf->size, true);  in drm_gem_cma_prime_import_sg_table()
453 	cma_obj->paddr = sg_dma_address(sgt->sgl);  in drm_gem_cma_prime_import_sg_table()
454 	cma_obj->sgt = sgt;  in drm_gem_cma_prime_import_sg_table()
456 	DRM_DEBUG_PRIME("dma_addr = %pad, size = %zu\n", &cma_obj->paddr, attach->dmabuf->size);  in drm_gem_cma_prime_import_sg_table()
458 	return &cma_obj->base;  in drm_gem_cma_prime_import_sg_table()
463  * drm_gem_cma_vmap - map a CMA GEM object into the kernel's virtual
482 	dma_buf_map_set_vaddr(map, cma_obj->vaddr);  in drm_gem_cma_vmap()
489  * drm_gem_cma_mmap - memory-map an exported CMA GEM object
495  * object instead of using on-demand faulting. Drivers that use the CMA
511 	vma->vm_pgoff -= drm_vma_node_start(&obj->vma_node);  in drm_gem_cma_mmap()
512 	vma->vm_flags &= ~VM_PFNMAP;  in drm_gem_cma_mmap()
516 	if (cma_obj->map_noncoherent) {  in drm_gem_cma_mmap()
517 		vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);  in drm_gem_cma_mmap()
519 		ret = dma_mmap_pages(cma_obj->base.dev->dev,  in drm_gem_cma_mmap()
520 				     vma, vma->vm_end - vma->vm_start,  in drm_gem_cma_mmap()
521 				     virt_to_page(cma_obj->vaddr));  in drm_gem_cma_mmap()
523 		ret = dma_mmap_wc(cma_obj->base.dev->dev, vma, cma_obj->vaddr,  in drm_gem_cma_mmap()
524 				  cma_obj->paddr, vma->vm_end - vma->vm_start);  in drm_gem_cma_mmap()
534  * drm_gem_cma_prime_import_sg_table_vmap - PRIME import another driver's
535  *	scatter/gather table and get the virtual address of the buffer
537  * @attach: DMA-BUF attachment
538  * @sgt: Scatter/gather table of pinned pages
540  * This function imports a scatter/gather table using
550  * A pointer to a newly created GEM object or an ERR_PTR-encoded negative
563 	ret = dma_buf_vmap(attach->dmabuf, &map);  in drm_gem_cma_prime_import_sg_table_vmap()
571 		dma_buf_vunmap(attach->dmabuf, &map);  in drm_gem_cma_prime_import_sg_table_vmap()
576 	cma_obj->vaddr = map.vaddr;  in drm_gem_cma_prime_import_sg_table_vmap()