--- zzzz-none-000/linux-3.10.107/drivers/gpu/drm/drm_gem.c 2017-06-27 09:49:32.000000000 +0000 +++ scorpion-7490-727/linux-3.10.107/drivers/gpu/drm/drm_gem.c 2021-02-04 17:41:59.000000000 +0000 @@ -37,6 +37,9 @@ #include #include #include +#include +#include +#include "drm_internal.h" /** @file drm_gem.c * @@ -84,36 +87,27 @@ #endif /** - * Initialize the GEM device fields + * drm_gem_init - Initialize the GEM device fields + * @dev: drm_devic structure to initialize */ - int drm_gem_init(struct drm_device *dev) { - struct drm_gem_mm *mm; + struct drm_vma_offset_manager *vma_offset_manager; - spin_lock_init(&dev->object_name_lock); + mutex_init(&dev->object_name_lock); idr_init(&dev->object_name_idr); - mm = kzalloc(sizeof(struct drm_gem_mm), GFP_KERNEL); - if (!mm) { + vma_offset_manager = kzalloc(sizeof(*vma_offset_manager), GFP_KERNEL); + if (!vma_offset_manager) { DRM_ERROR("out of memory\n"); return -ENOMEM; } - dev->mm_private = mm; - - if (drm_ht_create(&mm->offset_hash, 12)) { - kfree(mm); - return -ENOMEM; - } - - if (drm_mm_init(&mm->offset_manager, DRM_FILE_PAGE_OFFSET_START, - DRM_FILE_PAGE_OFFSET_SIZE)) { - drm_ht_remove(&mm->offset_hash); - kfree(mm); - return -ENOMEM; - } + dev->vma_offset_manager = vma_offset_manager; + drm_vma_offset_manager_init(vma_offset_manager, + DRM_FILE_PAGE_OFFSET_START, + DRM_FILE_PAGE_OFFSET_SIZE); return 0; } @@ -121,43 +115,50 @@ void drm_gem_destroy(struct drm_device *dev) { - struct drm_gem_mm *mm = dev->mm_private; - drm_mm_takedown(&mm->offset_manager); - drm_ht_remove(&mm->offset_hash); - kfree(mm); - dev->mm_private = NULL; + drm_vma_offset_manager_destroy(dev->vma_offset_manager); + kfree(dev->vma_offset_manager); + dev->vma_offset_manager = NULL; } /** + * drm_gem_object_init - initialize an allocated shmem-backed GEM object + * @dev: drm_device the object should be initialized for + * @obj: drm_gem_object to initialize + * @size: object size + * * Initialize an already allocated GEM object of the specified size with * shmfs backing store. */ int drm_gem_object_init(struct drm_device *dev, struct drm_gem_object *obj, size_t size) { - BUG_ON((size & (PAGE_SIZE - 1)) != 0); + struct file *filp; - obj->dev = dev; - obj->filp = shmem_file_setup("drm mm object", size, VM_NORESERVE); - if (IS_ERR(obj->filp)) - return PTR_ERR(obj->filp); + drm_gem_private_object_init(dev, obj, size); - kref_init(&obj->refcount); - atomic_set(&obj->handle_count, 0); - obj->size = size; + filp = shmem_file_setup("drm mm object", size, VM_NORESERVE); + if (IS_ERR(filp)) + return PTR_ERR(filp); + + obj->filp = filp; return 0; } EXPORT_SYMBOL(drm_gem_object_init); /** + * drm_gem_private_object_init - initialize an allocated private GEM object + * @dev: drm_device the object should be initialized for + * @obj: drm_gem_object to initialize + * @size: object size + * * Initialize an already allocated GEM object of the specified size with * no GEM provided backing store. Instead the caller is responsible for * backing the object and handling it. */ -int drm_gem_private_object_init(struct drm_device *dev, - struct drm_gem_object *obj, size_t size) +void drm_gem_private_object_init(struct drm_device *dev, + struct drm_gem_object *obj, size_t size) { BUG_ON((size & (PAGE_SIZE - 1)) != 0); @@ -165,57 +166,86 @@ obj->filp = NULL; kref_init(&obj->refcount); - atomic_set(&obj->handle_count, 0); + obj->handle_count = 0; obj->size = size; - - return 0; + drm_vma_node_reset(&obj->vma_node); } EXPORT_SYMBOL(drm_gem_private_object_init); +static void +drm_gem_remove_prime_handles(struct drm_gem_object *obj, struct drm_file *filp) +{ + /* + * Note: obj->dma_buf can't disappear as long as we still hold a + * handle reference in obj->handle_count. + */ + mutex_lock(&filp->prime.lock); + if (obj->dma_buf) { + drm_prime_remove_buf_handle_locked(&filp->prime, + obj->dma_buf); + } + mutex_unlock(&filp->prime.lock); +} + /** - * Allocate a GEM object of the specified size with shmfs backing store + * drm_gem_object_handle_free - release resources bound to userspace handles + * @obj: GEM object to clean up. + * + * Called after the last handle to the object has been closed + * + * Removes any name for the object. Note that this must be + * called before drm_gem_object_free or we'll be touching + * freed memory */ -struct drm_gem_object * -drm_gem_object_alloc(struct drm_device *dev, size_t size) +static void drm_gem_object_handle_free(struct drm_gem_object *obj) { - struct drm_gem_object *obj; - - obj = kzalloc(sizeof(*obj), GFP_KERNEL); - if (!obj) - goto free; + struct drm_device *dev = obj->dev; - if (drm_gem_object_init(dev, obj, size) != 0) - goto free; + /* Remove any name for this object */ + if (obj->name) { + idr_remove(&dev->object_name_idr, obj->name); + obj->name = 0; + } +} - if (dev->driver->gem_init_object != NULL && - dev->driver->gem_init_object(obj) != 0) { - goto fput; +static void drm_gem_object_exported_dma_buf_free(struct drm_gem_object *obj) +{ + /* Unbreak the reference cycle if we have an exported dma_buf. */ + if (obj->dma_buf) { + dma_buf_put(obj->dma_buf); + obj->dma_buf = NULL; } - return obj; -fput: - /* Object_init mangles the global counters - readjust them. */ - fput(obj->filp); -free: - kfree(obj); - return NULL; } -EXPORT_SYMBOL(drm_gem_object_alloc); static void -drm_gem_remove_prime_handles(struct drm_gem_object *obj, struct drm_file *filp) +drm_gem_object_handle_unreference_unlocked(struct drm_gem_object *obj) { - if (obj->import_attach) { - drm_prime_remove_buf_handle(&filp->prime, - obj->import_attach->dmabuf); - } - if (obj->export_dma_buf) { - drm_prime_remove_buf_handle(&filp->prime, - obj->export_dma_buf); + if (WARN_ON(obj->handle_count == 0)) + return; + + /* + * Must bump handle count first as this may be the last + * ref, in which case the object would disappear before we + * checked for a name + */ + + mutex_lock(&obj->dev->object_name_lock); + if (--obj->handle_count == 0) { + drm_gem_object_handle_free(obj); + drm_gem_object_exported_dma_buf_free(obj); } + mutex_unlock(&obj->dev->object_name_lock); + + drm_gem_object_unreference_unlocked(obj); } /** - * Removes the mapping from handle to filp for this object. + * drm_gem_handle_delete - deletes the given file-private handle + * @filp: drm file-private structure to use for the handle look up + * @handle: userspace handle to delete + * + * Removes the GEM handle from the @filp lookup table and if this is the last + * handle also cleans up linked resources like GEM names. */ int drm_gem_handle_delete(struct drm_file *filp, u32 handle) @@ -246,7 +276,9 @@ idr_remove(&filp->object_idr, handle); spin_unlock(&filp->table_lock); - drm_gem_remove_prime_handles(obj, filp); + if (drm_core_check_feature(dev, DRIVER_PRIME)) + drm_gem_remove_prime_handles(obj, filp); + drm_vma_node_revoke(&obj->vma_node, filp->filp); if (dev->driver->gem_close_object) dev->driver->gem_close_object(obj, filp); @@ -257,18 +289,42 @@ EXPORT_SYMBOL(drm_gem_handle_delete); /** - * Create a handle for this object. This adds a handle reference - * to the object, which includes a regular reference count. Callers - * will likely want to dereference the object afterwards. + * drm_gem_dumb_destroy - dumb fb callback helper for gem based drivers + * @file: drm file-private structure to remove the dumb handle from + * @dev: corresponding drm_device + * @handle: the dumb handle to remove + * + * This implements the ->dumb_destroy kms driver callback for drivers which use + * gem to manage their backing storage. + */ +int drm_gem_dumb_destroy(struct drm_file *file, + struct drm_device *dev, + uint32_t handle) +{ + return drm_gem_handle_delete(file, handle); +} +EXPORT_SYMBOL(drm_gem_dumb_destroy); + +/** + * drm_gem_handle_create_tail - internal functions to create a handle + * @file_priv: drm file-private structure to register the handle for + * @obj: object to register + * @handlep: pointer to return the created handle to the caller + * + * This expects the dev->object_name_lock to be held already and will drop it + * before returning. Used to avoid races in establishing new handles when + * importing an object from either an flink name or a dma-buf. */ int -drm_gem_handle_create(struct drm_file *file_priv, - struct drm_gem_object *obj, - u32 *handlep) +drm_gem_handle_create_tail(struct drm_file *file_priv, + struct drm_gem_object *obj, + u32 *handlep) { struct drm_device *dev = obj->dev; int ret; + WARN_ON(!mutex_is_locked(&dev->object_name_lock)); + /* * Get the user-visible handle using idr. Preload and perform * allocation under our spinlock. @@ -277,24 +333,56 @@ spin_lock(&file_priv->table_lock); ret = idr_alloc(&file_priv->object_idr, obj, 1, 0, GFP_NOWAIT); - + drm_gem_object_reference(obj); + obj->handle_count++; spin_unlock(&file_priv->table_lock); idr_preload_end(); + mutex_unlock(&dev->object_name_lock); if (ret < 0) - return ret; + goto err_unref; + *handlep = ret; - drm_gem_object_handle_reference(obj); + ret = drm_vma_node_allow(&obj->vma_node, file_priv->filp); + if (ret) + goto err_remove; if (dev->driver->gem_open_object) { ret = dev->driver->gem_open_object(obj, file_priv); - if (ret) { - drm_gem_handle_delete(file_priv, *handlep); - return ret; - } + if (ret) + goto err_revoke; } return 0; + +err_revoke: + drm_vma_node_revoke(&obj->vma_node, file_priv->filp); +err_remove: + spin_lock(&file_priv->table_lock); + idr_remove(&file_priv->object_idr, *handlep); + spin_unlock(&file_priv->table_lock); +err_unref: + drm_gem_object_handle_unreference_unlocked(obj); + return ret; +} + +/** + * drm_gem_handle_create - create a gem handle for an object + * @file_priv: drm file-private structure to register the handle for + * @obj: object to register + * @handlep: pionter to return the created handle to the caller + * + * Create a handle for this object. This adds a handle reference + * to the object, which includes a regular reference count. Callers + * will likely want to dereference the object afterwards. + */ +int drm_gem_handle_create(struct drm_file *file_priv, + struct drm_gem_object *obj, + u32 *handlep) +{ + mutex_lock(&obj->dev->object_name_lock); + + return drm_gem_handle_create_tail(file_priv, obj, handlep); } EXPORT_SYMBOL(drm_gem_handle_create); @@ -309,82 +397,154 @@ drm_gem_free_mmap_offset(struct drm_gem_object *obj) { struct drm_device *dev = obj->dev; - struct drm_gem_mm *mm = dev->mm_private; - struct drm_map_list *list = &obj->map_list; - drm_ht_remove_item(&mm->offset_hash, &list->hash); - drm_mm_put_block(list->file_offset_node); - kfree(list->map); - list->map = NULL; + drm_vma_offset_remove(dev->vma_offset_manager, &obj->vma_node); } EXPORT_SYMBOL(drm_gem_free_mmap_offset); /** - * drm_gem_create_mmap_offset - create a fake mmap offset for an object + * drm_gem_create_mmap_offset_size - create a fake mmap offset for an object * @obj: obj in question + * @size: the virtual size * * GEM memory mapping works by handing back to userspace a fake mmap offset * it can use in a subsequent mmap(2) call. The DRM core code then looks * up the object based on the offset and sets up the various memory mapping * structures. * - * This routine allocates and attaches a fake offset for @obj. + * This routine allocates and attaches a fake offset for @obj, in cases where + * the virtual size differs from the physical size (ie. obj->size). Otherwise + * just use drm_gem_create_mmap_offset(). */ int -drm_gem_create_mmap_offset(struct drm_gem_object *obj) +drm_gem_create_mmap_offset_size(struct drm_gem_object *obj, size_t size) { struct drm_device *dev = obj->dev; - struct drm_gem_mm *mm = dev->mm_private; - struct drm_map_list *list; - struct drm_local_map *map; - int ret; - /* Set the object up for mmap'ing */ - list = &obj->map_list; - list->map = kzalloc(sizeof(struct drm_map_list), GFP_KERNEL); - if (!list->map) - return -ENOMEM; + return drm_vma_offset_add(dev->vma_offset_manager, &obj->vma_node, + size / PAGE_SIZE); +} +EXPORT_SYMBOL(drm_gem_create_mmap_offset_size); - map = list->map; - map->type = _DRM_GEM; - map->size = obj->size; - map->handle = obj; - - /* Get a DRM GEM mmap offset allocated... */ - list->file_offset_node = drm_mm_search_free(&mm->offset_manager, - obj->size / PAGE_SIZE, 0, false); - - if (!list->file_offset_node) { - DRM_ERROR("failed to allocate offset for bo %d\n", obj->name); - ret = -ENOSPC; - goto out_free_list; - } - - list->file_offset_node = drm_mm_get_block(list->file_offset_node, - obj->size / PAGE_SIZE, 0); - if (!list->file_offset_node) { - ret = -ENOMEM; - goto out_free_list; - } - - list->hash.key = list->file_offset_node->start; - ret = drm_ht_insert_item(&mm->offset_hash, &list->hash); - if (ret) { - DRM_ERROR("failed to add to map hash\n"); - goto out_free_mm; +/** + * drm_gem_create_mmap_offset - create a fake mmap offset for an object + * @obj: obj in question + * + * GEM memory mapping works by handing back to userspace a fake mmap offset + * it can use in a subsequent mmap(2) call. The DRM core code then looks + * up the object based on the offset and sets up the various memory mapping + * structures. + * + * This routine allocates and attaches a fake offset for @obj. + */ +int drm_gem_create_mmap_offset(struct drm_gem_object *obj) +{ + return drm_gem_create_mmap_offset_size(obj, obj->size); +} +EXPORT_SYMBOL(drm_gem_create_mmap_offset); + +/** + * drm_gem_get_pages - helper to allocate backing pages for a GEM object + * from shmem + * @obj: obj in question + * + * This reads the page-array of the shmem-backing storage of the given gem + * object. An array of pages is returned. If a page is not allocated or + * swapped-out, this will allocate/swap-in the required pages. Note that the + * whole object is covered by the page-array and pinned in memory. + * + * Use drm_gem_put_pages() to release the array and unpin all pages. + * + * This uses the GFP-mask set on the shmem-mapping (see mapping_set_gfp_mask()). + * If you require other GFP-masks, you have to do those allocations yourself. + * + * Note that you are not allowed to change gfp-zones during runtime. That is, + * shmem_read_mapping_page_gfp() must be called with the same gfp_zone(gfp) as + * set during initialization. If you have special zone constraints, set them + * after drm_gem_init_object() via mapping_set_gfp_mask(). shmem-core takes care + * to keep pages in the required zone during swap-in. + */ +struct page **drm_gem_get_pages(struct drm_gem_object *obj) +{ + struct address_space *mapping; + struct page *p, **pages; + int i, npages; + + /* This is the shared memory object that backs the GEM resource */ + mapping = file_inode(obj->filp)->i_mapping; + + /* We already BUG_ON() for non-page-aligned sizes in + * drm_gem_object_init(), so we should never hit this unless + * driver author is doing something really wrong: + */ + WARN_ON((obj->size & (PAGE_SIZE - 1)) != 0); + + npages = obj->size >> PAGE_SHIFT; + + pages = drm_malloc_ab(npages, sizeof(struct page *)); + if (pages == NULL) + return ERR_PTR(-ENOMEM); + + for (i = 0; i < npages; i++) { + p = shmem_read_mapping_page(mapping, i); + if (IS_ERR(p)) + goto fail; + pages[i] = p; + + /* Make sure shmem keeps __GFP_DMA32 allocated pages in the + * correct region during swapin. Note that this requires + * __GFP_DMA32 to be set in mapping_gfp_mask(inode->i_mapping) + * so shmem can relocate pages during swapin if required. + */ + BUG_ON(mapping_gfp_constraint(mapping, __GFP_DMA32) && + (page_to_pfn(p) >= 0x00100000UL)); } - return 0; + return pages; -out_free_mm: - drm_mm_put_block(list->file_offset_node); -out_free_list: - kfree(list->map); - list->map = NULL; +fail: + while (i--) + page_cache_release(pages[i]); - return ret; + drm_free_large(pages); + return ERR_CAST(p); } -EXPORT_SYMBOL(drm_gem_create_mmap_offset); +EXPORT_SYMBOL(drm_gem_get_pages); + +/** + * drm_gem_put_pages - helper to free backing pages for a GEM object + * @obj: obj in question + * @pages: pages to free + * @dirty: if true, pages will be marked as dirty + * @accessed: if true, the pages will be marked as accessed + */ +void drm_gem_put_pages(struct drm_gem_object *obj, struct page **pages, + bool dirty, bool accessed) +{ + int i, npages; + + /* We already BUG_ON() for non-page-aligned sizes in + * drm_gem_object_init(), so we should never hit this unless + * driver author is doing something really wrong: + */ + WARN_ON((obj->size & (PAGE_SIZE - 1)) != 0); + + npages = obj->size >> PAGE_SHIFT; + + for (i = 0; i < npages; i++) { + if (dirty) + set_page_dirty(pages[i]); + + if (accessed) + mark_page_accessed(pages[i]); + + /* Undo the reference we took when populating the table */ + page_cache_release(pages[i]); + } + + drm_free_large(pages); +} +EXPORT_SYMBOL(drm_gem_put_pages); /** Returns a reference to the object named by the handle. */ struct drm_gem_object * @@ -411,6 +571,11 @@ EXPORT_SYMBOL(drm_gem_object_lookup); /** + * drm_gem_close_ioctl - implementation of the GEM_CLOSE ioctl + * @dev: drm_device + * @data: ioctl data + * @file_priv: drm file-private structure + * * Releases the handle to an mm object. */ int @@ -420,7 +585,7 @@ struct drm_gem_close *args = data; int ret; - if (!(dev->driver->driver_features & DRIVER_GEM)) + if (!drm_core_check_feature(dev, DRIVER_GEM)) return -ENODEV; ret = drm_gem_handle_delete(file_priv, args->handle); @@ -429,6 +594,11 @@ } /** + * drm_gem_flink_ioctl - implementation of the GEM_FLINK ioctl + * @dev: drm_device + * @data: ioctl data + * @file_priv: drm file-private structure + * * Create a global name for an object, returning the name. * * Note that the name does not hold a reference; when the object @@ -442,37 +612,45 @@ struct drm_gem_object *obj; int ret; - if (!(dev->driver->driver_features & DRIVER_GEM)) + if (!drm_core_check_feature(dev, DRIVER_GEM)) return -ENODEV; obj = drm_gem_object_lookup(dev, file_priv, args->handle); if (obj == NULL) return -ENOENT; + mutex_lock(&dev->object_name_lock); idr_preload(GFP_KERNEL); - spin_lock(&dev->object_name_lock); + /* prevent races with concurrent gem_close. */ + if (obj->handle_count == 0) { + ret = -ENOENT; + goto err; + } + if (!obj->name) { ret = idr_alloc(&dev->object_name_idr, obj, 1, 0, GFP_NOWAIT); if (ret < 0) goto err; obj->name = ret; - - /* Allocate a reference for the name table. */ - drm_gem_object_reference(obj); } args->name = (uint64_t) obj->name; ret = 0; err: - spin_unlock(&dev->object_name_lock); idr_preload_end(); + mutex_unlock(&dev->object_name_lock); drm_gem_object_unreference_unlocked(obj); return ret; } /** + * drm_gem_open - implementation of the GEM_OPEN ioctl + * @dev: drm_device + * @data: ioctl data + * @file_priv: drm file-private structure + * * Open an object using the global name, returning a handle and the size. * * This handle (of course) holds a reference to the object, so the object @@ -487,18 +665,20 @@ int ret; u32 handle; - if (!(dev->driver->driver_features & DRIVER_GEM)) + if (!drm_core_check_feature(dev, DRIVER_GEM)) return -ENODEV; - spin_lock(&dev->object_name_lock); + mutex_lock(&dev->object_name_lock); obj = idr_find(&dev->object_name_idr, (int) args->name); - if (obj) + if (obj) { drm_gem_object_reference(obj); - spin_unlock(&dev->object_name_lock); - if (!obj) + } else { + mutex_unlock(&dev->object_name_lock); return -ENOENT; + } - ret = drm_gem_handle_create(file_priv, obj, &handle); + /* drm_gem_handle_create_tail unlocks dev->object_name_lock. */ + ret = drm_gem_handle_create_tail(file_priv, obj, &handle); drm_gem_object_unreference_unlocked(obj); if (ret) return ret; @@ -510,6 +690,10 @@ } /** + * gem_gem_open - initalizes GEM file-private structures at devnode open time + * @dev: drm_device which is being opened by userspace + * @file_private: drm file-private structure to set up + * * Called at device open time, sets up the structure for handling refcounting * of mm objects. */ @@ -520,7 +704,7 @@ spin_lock_init(&file_private->table_lock); } -/** +/* * Called at device close to release the file's * handle references on objects. */ @@ -531,7 +715,9 @@ struct drm_gem_object *obj = ptr; struct drm_device *dev = obj->dev; - drm_gem_remove_prime_handles(obj, file_priv); + if (drm_core_check_feature(dev, DRIVER_PRIME)) + drm_gem_remove_prime_handles(obj, file_priv); + drm_vma_node_revoke(&obj->vma_node, file_priv->filp); if (dev->driver->gem_close_object) dev->driver->gem_close_object(obj, file_priv); @@ -542,6 +728,10 @@ } /** + * drm_gem_release - release file-private GEM resources + * @dev: drm_device which is being closed by userspace + * @file_private: drm file-private structure to clean up + * * Called at close time when the filp is going away. * * Releases any remaining references on objects by this filp. @@ -557,12 +747,19 @@ void drm_gem_object_release(struct drm_gem_object *obj) { + WARN_ON(obj->dma_buf); + if (obj->filp) - fput(obj->filp); + fput(obj->filp); + + drm_gem_free_mmap_offset(obj); } EXPORT_SYMBOL(drm_gem_object_release); /** + * drm_gem_object_free - free a GEM object + * @kref: kref of the object to free + * * Called after the last reference to the object has been lost. * Must be called holding struct_ mutex * @@ -571,75 +768,85 @@ void drm_gem_object_free(struct kref *kref) { - struct drm_gem_object *obj = (struct drm_gem_object *) kref; + struct drm_gem_object *obj = + container_of(kref, struct drm_gem_object, refcount); struct drm_device *dev = obj->dev; - BUG_ON(!mutex_is_locked(&dev->struct_mutex)); + WARN_ON(!mutex_is_locked(&dev->struct_mutex)); if (dev->driver->gem_free_object != NULL) dev->driver->gem_free_object(obj); } EXPORT_SYMBOL(drm_gem_object_free); -static void drm_gem_object_ref_bug(struct kref *list_kref) -{ - BUG(); -} - -/** - * Called after the last handle to the object has been closed - * - * Removes any name for the object. Note that this must be - * called before drm_gem_object_free or we'll be touching - * freed memory - */ -void drm_gem_object_handle_free(struct drm_gem_object *obj) -{ - struct drm_device *dev = obj->dev; - - /* Remove any name for this object */ - spin_lock(&dev->object_name_lock); - if (obj->name) { - idr_remove(&dev->object_name_idr, obj->name); - obj->name = 0; - spin_unlock(&dev->object_name_lock); - /* - * The object name held a reference to this object, drop - * that now. - * - * This cannot be the last reference, since the handle holds one too. - */ - kref_put(&obj->refcount, drm_gem_object_ref_bug); - } else - spin_unlock(&dev->object_name_lock); - -} -EXPORT_SYMBOL(drm_gem_object_handle_free); - void drm_gem_vm_open(struct vm_area_struct *vma) { struct drm_gem_object *obj = vma->vm_private_data; drm_gem_object_reference(obj); - - mutex_lock(&obj->dev->struct_mutex); - drm_vm_open_locked(obj->dev, vma); - mutex_unlock(&obj->dev->struct_mutex); } EXPORT_SYMBOL(drm_gem_vm_open); void drm_gem_vm_close(struct vm_area_struct *vma) { struct drm_gem_object *obj = vma->vm_private_data; - struct drm_device *dev = obj->dev; - mutex_lock(&dev->struct_mutex); - drm_vm_close_locked(obj->dev, vma); - drm_gem_object_unreference(obj); - mutex_unlock(&dev->struct_mutex); + drm_gem_object_unreference_unlocked(obj); } EXPORT_SYMBOL(drm_gem_vm_close); +/** + * drm_gem_mmap_obj - memory map a GEM object + * @obj: the GEM object to map + * @obj_size: the object size to be mapped, in bytes + * @vma: VMA for the area to be mapped + * + * Set up the VMA to prepare mapping of the GEM object using the gem_vm_ops + * provided by the driver. Depending on their requirements, drivers can either + * provide a fault handler in their gem_vm_ops (in which case any accesses to + * the object will be trapped, to perform migration, GTT binding, surface + * register allocation, or performance monitoring), or mmap the buffer memory + * synchronously after calling drm_gem_mmap_obj. + * + * This function is mainly intended to implement the DMABUF mmap operation, when + * the GEM object is not looked up based on its fake offset. To implement the + * DRM mmap operation, drivers should use the drm_gem_mmap() function. + * + * drm_gem_mmap_obj() assumes the user is granted access to the buffer while + * drm_gem_mmap() prevents unprivileged users from mapping random objects. So + * callers must verify access restrictions before calling this helper. + * + * Return 0 or success or -EINVAL if the object size is smaller than the VMA + * size, or if no gem_vm_ops are provided. + */ +int drm_gem_mmap_obj(struct drm_gem_object *obj, unsigned long obj_size, + struct vm_area_struct *vma) +{ + struct drm_device *dev = obj->dev; + + /* Check for valid size. */ + if (obj_size < vma->vm_end - vma->vm_start) + return -EINVAL; + + if (!dev->driver->gem_vm_ops) + return -EINVAL; + + vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP; + vma->vm_ops = dev->driver->gem_vm_ops; + vma->vm_private_data = obj; + vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags)); + + /* Take a ref for this mapping of the object, so that the fault + * handler can dereference the mmap offset's pointer to the object. + * This reference is cleaned up by the corresponding vm_close + * (which should happen whether the vma was created by this call, or + * by a vm_open due to mremap or partial unmap or whatever). + */ + drm_gem_object_reference(obj); + + return 0; +} +EXPORT_SYMBOL(drm_gem_mmap_obj); /** * drm_gem_mmap - memory map routine for GEM objects @@ -649,68 +856,57 @@ * If a driver supports GEM object mapping, mmap calls on the DRM file * descriptor will end up here. * - * If we find the object based on the offset passed in (vma->vm_pgoff will + * Look up the GEM object based on the offset passed in (vma->vm_pgoff will * contain the fake offset we created when the GTT map ioctl was called on - * the object), we set up the driver fault handler so that any accesses - * to the object can be trapped, to perform migration, GTT binding, surface - * register allocation, or performance monitoring. + * the object) and map it with a call to drm_gem_mmap_obj(). + * + * If the caller is not granted access to the buffer object, the mmap will fail + * with EACCES. Please see the vma manager for more information. */ int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma) { struct drm_file *priv = filp->private_data; struct drm_device *dev = priv->minor->dev; - struct drm_gem_mm *mm = dev->mm_private; - struct drm_local_map *map = NULL; - struct drm_gem_object *obj; - struct drm_hash_item *hash; - int ret = 0; + struct drm_gem_object *obj = NULL; + struct drm_vma_offset_node *node; + int ret; if (drm_device_is_unplugged(dev)) return -ENODEV; - mutex_lock(&dev->struct_mutex); - - if (drm_ht_find_item(&mm->offset_hash, vma->vm_pgoff, &hash)) { - mutex_unlock(&dev->struct_mutex); - return drm_mmap(filp, vma); - } - - map = drm_hash_entry(hash, struct drm_map_list, hash)->map; - if (!map || - ((map->flags & _DRM_RESTRICTED) && !capable(CAP_SYS_ADMIN))) { - ret = -EPERM; - goto out_unlock; + drm_vma_offset_lock_lookup(dev->vma_offset_manager); + node = drm_vma_offset_exact_lookup_locked(dev->vma_offset_manager, + vma->vm_pgoff, + vma_pages(vma)); + if (likely(node)) { + obj = container_of(node, struct drm_gem_object, vma_node); + /* + * When the object is being freed, after it hits 0-refcnt it + * proceeds to tear down the object. In the process it will + * attempt to remove the VMA offset and so acquire this + * mgr->vm_lock. Therefore if we find an object with a 0-refcnt + * that matches our range, we know it is in the process of being + * destroyed and will be freed as soon as we release the lock - + * so we have to check for the 0-refcnted object and treat it as + * invalid. + */ + if (!kref_get_unless_zero(&obj->refcount)) + obj = NULL; } + drm_vma_offset_unlock_lookup(dev->vma_offset_manager); - /* Check for valid size. */ - if (map->size < vma->vm_end - vma->vm_start) { - ret = -EINVAL; - goto out_unlock; - } + if (!obj) + return -EINVAL; - obj = map->handle; - if (!obj->dev->driver->gem_vm_ops) { - ret = -EINVAL; - goto out_unlock; + if (!drm_vma_node_is_allowed(node, filp)) { + drm_gem_object_unreference_unlocked(obj); + return -EACCES; } - vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP; - vma->vm_ops = obj->dev->driver->gem_vm_ops; - vma->vm_private_data = map->handle; - vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags)); - - /* Take a ref for this mapping of the object, so that the fault - * handler can dereference the mmap offset's pointer to the object. - * This reference is cleaned up by the corresponding vm_close - * (which should happen whether the vma was created by this call, or - * by a vm_open due to mremap or partial unmap or whatever). - */ - drm_gem_object_reference(obj); - - drm_vm_open_locked(dev, vma); + ret = drm_gem_mmap_obj(obj, drm_vma_node_size(node) << PAGE_SHIFT, + vma); -out_unlock: - mutex_unlock(&dev->struct_mutex); + drm_gem_object_unreference_unlocked(obj); return ret; }