diff options
Diffstat (limited to 'drivers/gpu/drm/drm_gem.c')
| -rw-r--r-- | drivers/gpu/drm/drm_gem.c | 645 |
1 files changed, 404 insertions, 241 deletions
diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c index 24efae464e2..f7d71190aad 100644 --- a/drivers/gpu/drm/drm_gem.c +++ b/drivers/gpu/drm/drm_gem.c @@ -37,6 +37,7 @@ #include <linux/shmem_fs.h> #include <linux/dma-buf.h> #include <drm/drmP.h> +#include <drm/drm_vma_manager.h> /** @file drm_gem.c * @@ -84,36 +85,27 @@ #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 +113,50 @@ drm_gem_init(struct drm_device *dev) 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_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 +164,86 @@ int drm_gem_private_object_init(struct drm_device *dev, 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_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_imported_buf_handle(&filp->prime, - obj->import_attach->dmabuf); - } - if (obj->export_dma_buf) { - drm_prime_remove_imported_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 +274,9 @@ drm_gem_handle_delete(struct drm_file *filp, u32 handle) 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); @@ -257,36 +287,66 @@ drm_gem_handle_delete(struct drm_file *filp, u32 handle) 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: pionter 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. + * Get the user-visible handle using idr. Preload and perform + * allocation under our spinlock. */ -again: - /* ensure there is space available to allocate a handle */ - if (idr_pre_get(&file_priv->object_idr, GFP_KERNEL) == 0) - return -ENOMEM; - - /* do the allocation under our spinlock */ + idr_preload(GFP_KERNEL); spin_lock(&file_priv->table_lock); - ret = idr_get_new_above(&file_priv->object_idr, obj, 1, (int *)handlep); + + 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); - if (ret == -EAGAIN) - goto again; - else if (ret) + idr_preload_end(); + mutex_unlock(&dev->object_name_lock); + if (ret < 0) { + drm_gem_object_handle_unreference_unlocked(obj); return ret; + } + *handlep = ret; - drm_gem_object_handle_reference(obj); + ret = drm_vma_node_allow(&obj->vma_node, file_priv->filp); + if (ret) { + drm_gem_handle_delete(file_priv, *handlep); + return ret; + } if (dev->driver->gem_open_object) { ret = dev->driver->gem_open_object(obj, file_priv); @@ -298,6 +358,26 @@ again: return 0; } + +/** + * 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); @@ -311,82 +391,143 @@ void 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; +/** + * 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); - /* Get a DRM GEM mmap offset allocated... */ - list->file_offset_node = drm_mm_search_free(&mm->offset_manager, - obj->size / PAGE_SIZE, 0, false); +/** + * drm_gem_get_pages - helper to allocate backing pages for a GEM object + * from shmem + * @obj: obj in question + * @gfpmask: gfp mask of requested pages + */ +struct page **drm_gem_get_pages(struct drm_gem_object *obj, gfp_t gfpmask) +{ + struct inode *inode; + struct address_space *mapping; + struct page *p, **pages; + int i, npages; + + /* This is the shared memory object that backs the GEM resource */ + inode = file_inode(obj->filp); + mapping = inode->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); - if (!list->file_offset_node) { - DRM_ERROR("failed to allocate offset for bo %d\n", obj->name); - ret = -ENOSPC; - goto out_free_list; - } + npages = obj->size >> PAGE_SHIFT; - 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; - } + pages = drm_malloc_ab(npages, sizeof(struct page *)); + if (pages == NULL) + return ERR_PTR(-ENOMEM); - 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; + gfpmask |= mapping_gfp_mask(mapping); + + for (i = 0; i < npages; i++) { + p = shmem_read_mapping_page_gfp(mapping, i, gfpmask); + 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((gfpmask & __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 * @@ -413,6 +554,11 @@ drm_gem_object_lookup(struct drm_device *dev, struct drm_file *filp, 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 @@ -431,6 +577,11 @@ drm_gem_close_ioctl(struct drm_device *dev, void *data, } /** + * 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 @@ -451,38 +602,38 @@ drm_gem_flink_ioctl(struct drm_device *dev, void *data, if (obj == NULL) return -ENOENT; -again: - if (idr_pre_get(&dev->object_name_idr, GFP_KERNEL) == 0) { - ret = -ENOMEM; + mutex_lock(&dev->object_name_lock); + idr_preload(GFP_KERNEL); + /* prevent races with concurrent gem_close. */ + if (obj->handle_count == 0) { + ret = -ENOENT; goto err; } - spin_lock(&dev->object_name_lock); if (!obj->name) { - ret = idr_get_new_above(&dev->object_name_idr, obj, 1, - &obj->name); - args->name = (uint64_t) obj->name; - spin_unlock(&dev->object_name_lock); - - if (ret == -EAGAIN) - goto again; - else if (ret) + ret = idr_alloc(&dev->object_name_idr, obj, 1, 0, GFP_NOWAIT); + if (ret < 0) goto err; - /* Allocate a reference for the name table. */ - drm_gem_object_reference(obj); - } else { - args->name = (uint64_t) obj->name; - spin_unlock(&dev->object_name_lock); - ret = 0; + obj->name = ret; } + args->name = (uint64_t) obj->name; + ret = 0; + err: + 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 @@ -500,15 +651,17 @@ drm_gem_open_ioctl(struct drm_device *dev, void *data, if (!(dev->driver->driver_features & 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; @@ -520,6 +673,10 @@ drm_gem_open_ioctl(struct drm_device *dev, void *data, } /** + * 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. */ @@ -530,7 +687,7 @@ drm_gem_open(struct drm_device *dev, struct drm_file *file_private) spin_lock_init(&file_private->table_lock); } -/** +/* * Called at device close to release the file's * handle references on objects. */ @@ -541,7 +698,9 @@ drm_gem_object_release_handle(int id, void *ptr, void *data) 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); @@ -552,6 +711,10 @@ drm_gem_object_release_handle(int id, void *ptr, void *data) } /** + * 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. @@ -561,20 +724,25 @@ drm_gem_release(struct drm_device *dev, struct drm_file *file_private) { idr_for_each(&file_private->object_idr, &drm_gem_object_release_handle, file_private); - - idr_remove_all(&file_private->object_idr); idr_destroy(&file_private->object_idr); } 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 * @@ -593,41 +761,6 @@ drm_gem_object_free(struct kref *kref) } 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; @@ -652,6 +785,63 @@ void drm_gem_vm_close(struct vm_area_struct *vma) } 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. + * + * NOTE: This function has to be protected with dev->struct_mutex + * + * 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; + + lockdep_assert_held(&dev->struct_mutex); + + /* 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); + + drm_vm_open_locked(dev, vma); + return 0; +} +EXPORT_SYMBOL(drm_gem_mmap_obj); /** * drm_gem_mmap - memory map routine for GEM objects @@ -661,67 +851,40 @@ EXPORT_SYMBOL(drm_gem_vm_close); * 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_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)) { + node = drm_vma_offset_exact_lookup(dev->vma_offset_manager, + vma->vm_pgoff, + vma_pages(vma)); + if (!node) { mutex_unlock(&dev->struct_mutex); return drm_mmap(filp, vma); + } else if (!drm_vma_node_is_allowed(node, filp)) { + mutex_unlock(&dev->struct_mutex); + return -EACCES; } - 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; - } - - /* Check for valid size. */ - if (map->size < vma->vm_end - vma->vm_start) { - ret = -EINVAL; - goto out_unlock; - } - - obj = map->handle; - if (!obj->dev->driver->gem_vm_ops) { - ret = -EINVAL; - goto out_unlock; - } - - 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); + obj = container_of(node, struct drm_gem_object, vma_node); + ret = drm_gem_mmap_obj(obj, drm_vma_node_size(node) << PAGE_SHIFT, vma); -out_unlock: mutex_unlock(&dev->struct_mutex); return ret; |
