| /* |
| * Copyright © 2008 Intel Corporation |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining a |
| * copy of this software and associated documentation files (the "Software"), |
| * to deal in the Software without restriction, including without limitation |
| * the rights to use, copy, modify, merge, publish, distribute, sublicense, |
| * and/or sell copies of the Software, and to permit persons to whom the |
| * Software is furnished to do so, subject to the following conditions: |
| * |
| * The above copyright notice and this permission notice (including the next |
| * paragraph) shall be included in all copies or substantial portions of the |
| * Software. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING |
| * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS |
| * IN THE SOFTWARE. |
| * |
| * Authors: |
| * Eric Anholt <eric@anholt.net> |
| * |
| */ |
| |
| #include <linux/types.h> |
| #include <linux/slab.h> |
| #include <linux/mm.h> |
| #include <linux/uaccess.h> |
| #include <linux/fs.h> |
| #include <linux/file.h> |
| #include <linux/module.h> |
| #include <linux/mman.h> |
| #include <linux/pagemap.h> |
| #include <linux/shmem_fs.h> |
| #include <linux/dma-buf.h> |
| #include <drm/drmP.h> |
| #include <drm/drm_vma_manager.h> |
| |
| /** @file drm_gem.c |
| * |
| * This file provides some of the base ioctls and library routines for |
| * the graphics memory manager implemented by each device driver. |
| * |
| * Because various devices have different requirements in terms of |
| * synchronization and migration strategies, implementing that is left up to |
| * the driver, and all that the general API provides should be generic -- |
| * allocating objects, reading/writing data with the cpu, freeing objects. |
| * Even there, platform-dependent optimizations for reading/writing data with |
| * the CPU mean we'll likely hook those out to driver-specific calls. However, |
| * the DRI2 implementation wants to have at least allocate/mmap be generic. |
| * |
| * The goal was to have swap-backed object allocation managed through |
| * struct file. However, file descriptors as handles to a struct file have |
| * two major failings: |
| * - Process limits prevent more than 1024 or so being used at a time by |
| * default. |
| * - Inability to allocate high fds will aggravate the X Server's select() |
| * handling, and likely that of many GL client applications as well. |
| * |
| * This led to a plan of using our own integer IDs (called handles, following |
| * DRM terminology) to mimic fds, and implement the fd syscalls we need as |
| * ioctls. The objects themselves will still include the struct file so |
| * that we can transition to fds if the required kernel infrastructure shows |
| * up at a later date, and as our interface with shmfs for memory allocation. |
| */ |
| |
| /* |
| * We make up offsets for buffer objects so we can recognize them at |
| * mmap time. |
| */ |
| |
| /* pgoff in mmap is an unsigned long, so we need to make sure that |
| * the faked up offset will fit |
| */ |
| |
| #if BITS_PER_LONG == 64 |
| #define DRM_FILE_PAGE_OFFSET_START ((0xFFFFFFFFUL >> PAGE_SHIFT) + 1) |
| #define DRM_FILE_PAGE_OFFSET_SIZE ((0xFFFFFFFFUL >> PAGE_SHIFT) * 16) |
| #else |
| #define DRM_FILE_PAGE_OFFSET_START ((0xFFFFFFFUL >> PAGE_SHIFT) + 1) |
| #define DRM_FILE_PAGE_OFFSET_SIZE ((0xFFFFFFFUL >> PAGE_SHIFT) * 16) |
| #endif |
| |
| /** |
| * Initialize the GEM device fields |
| */ |
| |
| int |
| drm_gem_init(struct drm_device *dev) |
| { |
| struct drm_vma_offset_manager *vma_offset_manager; |
| |
| mutex_init(&dev->object_name_lock); |
| idr_init(&dev->object_name_idr); |
| |
| vma_offset_manager = kzalloc(sizeof(*vma_offset_manager), GFP_KERNEL); |
| if (!vma_offset_manager) { |
| DRM_ERROR("out of memory\n"); |
| 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; |
| } |
| |
| void |
| drm_gem_destroy(struct drm_device *dev) |
| { |
| |
| drm_vma_offset_manager_destroy(dev->vma_offset_manager); |
| kfree(dev->vma_offset_manager); |
| dev->vma_offset_manager = NULL; |
| } |
| |
| /** |
| * 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) |
| { |
| struct file *filp; |
| |
| filp = shmem_file_setup("drm mm object", size, VM_NORESERVE); |
| if (IS_ERR(filp)) |
| return PTR_ERR(filp); |
| |
| drm_gem_private_object_init(dev, obj, size); |
| obj->filp = filp; |
| |
| return 0; |
| } |
| EXPORT_SYMBOL(drm_gem_object_init); |
| |
| /** |
| * 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. |
| */ |
| 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); |
| |
| obj->dev = dev; |
| obj->filp = NULL; |
| |
| kref_init(&obj->refcount); |
| obj->handle_count = 0; |
| obj->size = size; |
| 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); |
| } |
| |
| /** |
| * 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 |
| */ |
| static void drm_gem_object_handle_free(struct drm_gem_object *obj) |
| { |
| struct drm_device *dev = obj->dev; |
| |
| /* Remove any name for this object */ |
| if (obj->name) { |
| idr_remove(&dev->object_name_idr, obj->name); |
| obj->name = 0; |
| } |
| } |
| |
| 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; |
| } |
| } |
| |
| static void |
| drm_gem_object_handle_unreference_unlocked(struct drm_gem_object *obj) |
| { |
| 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. |
| */ |
| int |
| drm_gem_handle_delete(struct drm_file *filp, u32 handle) |
| { |
| struct drm_device *dev; |
| struct drm_gem_object *obj; |
| |
| /* This is gross. The idr system doesn't let us try a delete and |
| * return an error code. It just spews if you fail at deleting. |
| * So, we have to grab a lock around finding the object and then |
| * doing the delete on it and dropping the refcount, or the user |
| * could race us to double-decrement the refcount and cause a |
| * use-after-free later. Given the frequency of our handle lookups, |
| * we may want to use ida for number allocation and a hash table |
| * for the pointers, anyway. |
| */ |
| spin_lock(&filp->table_lock); |
| |
| /* Check if we currently have a reference on the object */ |
| obj = idr_find(&filp->object_idr, handle); |
| if (obj == NULL) { |
| spin_unlock(&filp->table_lock); |
| return -EINVAL; |
| } |
| dev = obj->dev; |
| |
| /* Release reference and decrement refcount. */ |
| idr_remove(&filp->object_idr, handle); |
| spin_unlock(&filp->table_lock); |
| |
| 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); |
| drm_gem_object_handle_unreference_unlocked(obj); |
| |
| return 0; |
| } |
| EXPORT_SYMBOL(drm_gem_handle_delete); |
| |
| /** |
| * drm_gem_dumb_destroy - dumb fb callback helper for gem based drivers |
| * |
| * 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 |
| * |
| * 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_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. |
| */ |
| idr_preload(GFP_KERNEL); |
| 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) { |
| drm_gem_object_handle_unreference_unlocked(obj); |
| return ret; |
| } |
| *handlep = ret; |
| |
| 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); |
| if (ret) { |
| drm_gem_handle_delete(file_priv, *handlep); |
| return ret; |
| } |
| } |
| |
| return 0; |
| } |
| |
| /** |
| * 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); |
| |
| |
| /** |
| * drm_gem_free_mmap_offset - release a fake mmap offset for an object |
| * @obj: obj in question |
| * |
| * This routine frees fake offsets allocated by drm_gem_create_mmap_offset(). |
| */ |
| void |
| drm_gem_free_mmap_offset(struct drm_gem_object *obj) |
| { |
| struct drm_device *dev = obj->dev; |
| |
| drm_vma_offset_remove(dev->vma_offset_manager, &obj->vma_node); |
| } |
| EXPORT_SYMBOL(drm_gem_free_mmap_offset); |
| |
| /** |
| * 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, 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_size(struct drm_gem_object *obj, size_t size) |
| { |
| struct drm_device *dev = obj->dev; |
| |
| return drm_vma_offset_add(dev->vma_offset_manager, &obj->vma_node, |
| size / PAGE_SIZE); |
| } |
| EXPORT_SYMBOL(drm_gem_create_mmap_offset_size); |
| |
| /** |
| * 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 |
| * @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); |
| |
| npages = obj->size >> PAGE_SHIFT; |
| |
| pages = drm_malloc_ab(npages, sizeof(struct page *)); |
| if (pages == NULL) |
| return ERR_PTR(-ENOMEM); |
| |
| 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; |
| |
| /* There is a hypothetical issue w/ drivers that require |
| * buffer memory in the low 4GB.. if the pages are un- |
| * pinned, and swapped out, they can end up swapped back |
| * in above 4GB. If pages are already in memory, then |
| * shmem_read_mapping_page_gfp will ignore the gfpmask, |
| * even if the already in-memory page disobeys the mask. |
| * |
| * It is only a theoretical issue today, because none of |
| * the devices with this limitation can be populated with |
| * enough memory to trigger the issue. But this BUG_ON() |
| * is here as a reminder in case the problem with |
| * shmem_read_mapping_page_gfp() isn't solved by the time |
| * it does become a real issue. |
| * |
| * See this thread: http://lkml.org/lkml/2011/7/11/238 |
| */ |
| BUG_ON((gfpmask & __GFP_DMA32) && |
| (page_to_pfn(p) >= 0x00100000UL)); |
| } |
| |
| return pages; |
| |
| fail: |
| while (i--) |
| page_cache_release(pages[i]); |
| |
| drm_free_large(pages); |
| return ERR_CAST(p); |
| } |
| 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 * |
| drm_gem_object_lookup(struct drm_device *dev, struct drm_file *filp, |
| u32 handle) |
| { |
| struct drm_gem_object *obj; |
| |
| spin_lock(&filp->table_lock); |
| |
| /* Check if we currently have a reference on the object */ |
| obj = idr_find(&filp->object_idr, handle); |
| if (obj == NULL) { |
| spin_unlock(&filp->table_lock); |
| return NULL; |
| } |
| |
| drm_gem_object_reference(obj); |
| |
| spin_unlock(&filp->table_lock); |
| |
| return obj; |
| } |
| EXPORT_SYMBOL(drm_gem_object_lookup); |
| |
| /** |
| * Releases the handle to an mm object. |
| */ |
| int |
| drm_gem_close_ioctl(struct drm_device *dev, void *data, |
| struct drm_file *file_priv) |
| { |
| struct drm_gem_close *args = data; |
| int ret; |
| |
| if (!(dev->driver->driver_features & DRIVER_GEM)) |
| return -ENODEV; |
| |
| ret = drm_gem_handle_delete(file_priv, args->handle); |
| |
| return ret; |
| } |
| |
| /** |
| * Create a global name for an object, returning the name. |
| * |
| * Note that the name does not hold a reference; when the object |
| * is freed, the name goes away. |
| */ |
| int |
| drm_gem_flink_ioctl(struct drm_device *dev, void *data, |
| struct drm_file *file_priv) |
| { |
| struct drm_gem_flink *args = data; |
| struct drm_gem_object *obj; |
| int ret; |
| |
| if (!(dev->driver->driver_features & 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); |
| /* 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; |
| } |
| |
| 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; |
| } |
| |
| /** |
| * 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 |
| * will not go away until the handle is deleted. |
| */ |
| int |
| drm_gem_open_ioctl(struct drm_device *dev, void *data, |
| struct drm_file *file_priv) |
| { |
| struct drm_gem_open *args = data; |
| struct drm_gem_object *obj; |
| int ret; |
| u32 handle; |
| |
| if (!(dev->driver->driver_features & DRIVER_GEM)) |
| return -ENODEV; |
| |
| mutex_lock(&dev->object_name_lock); |
| obj = idr_find(&dev->object_name_idr, (int) args->name); |
| if (obj) { |
| drm_gem_object_reference(obj); |
| } else { |
| mutex_unlock(&dev->object_name_lock); |
| return -ENOENT; |
| } |
| |
| /* 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; |
| |
| args->handle = handle; |
| args->size = obj->size; |
| |
| return 0; |
| } |
| |
| /** |
| * Called at device open time, sets up the structure for handling refcounting |
| * of mm objects. |
| */ |
| void |
| drm_gem_open(struct drm_device *dev, struct drm_file *file_private) |
| { |
| idr_init(&file_private->object_idr); |
| spin_lock_init(&file_private->table_lock); |
| } |
| |
| /** |
| * Called at device close to release the file's |
| * handle references on objects. |
| */ |
| static int |
| drm_gem_object_release_handle(int id, void *ptr, void *data) |
| { |
| struct drm_file *file_priv = data; |
| struct drm_gem_object *obj = ptr; |
| struct drm_device *dev = obj->dev; |
| |
| 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); |
| |
| drm_gem_object_handle_unreference_unlocked(obj); |
| |
| return 0; |
| } |
| |
| /** |
| * Called at close time when the filp is going away. |
| * |
| * Releases any remaining references on objects by this filp. |
| */ |
| void |
| 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_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); |
| } |
| EXPORT_SYMBOL(drm_gem_object_release); |
| |
| /** |
| * Called after the last reference to the object has been lost. |
| * Must be called holding struct_ mutex |
| * |
| * Frees the object |
| */ |
| void |
| drm_gem_object_free(struct kref *kref) |
| { |
| struct drm_gem_object *obj = (struct drm_gem_object *) kref; |
| struct drm_device *dev = obj->dev; |
| |
| BUG_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); |
| |
| 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); |
| } |
| 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 |
| * @filp: DRM file pointer |
| * @vma: VMA for the area to be mapped |
| * |
| * If a driver supports GEM object mapping, mmap calls on the DRM file |
| * descriptor will end up here. |
| * |
| * 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) 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_object *obj; |
| struct drm_vma_offset_node *node; |
| int ret = 0; |
| |
| if (drm_device_is_unplugged(dev)) |
| return -ENODEV; |
| |
| mutex_lock(&dev->struct_mutex); |
| |
| 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; |
| } |
| |
| obj = container_of(node, struct drm_gem_object, vma_node); |
| ret = drm_gem_mmap_obj(obj, drm_vma_node_size(node) << PAGE_SHIFT, vma); |
| |
| mutex_unlock(&dev->struct_mutex); |
| |
| return ret; |
| } |
| EXPORT_SYMBOL(drm_gem_mmap); |