2 * Copyright © 2008 Intel Corporation
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
24 * Eric Anholt <eric@anholt.net>
28 #include <linux/types.h>
29 #include <linux/slab.h>
31 #include <linux/uaccess.h>
33 #include <linux/file.h>
34 #include <linux/module.h>
35 #include <linux/mman.h>
36 #include <linux/pagemap.h>
37 #include <linux/shmem_fs.h>
38 #include <linux/dma-buf.h>
39 #include <linux/mem_encrypt.h>
40 #include <linux/pagevec.h>
42 #include <drm/drm_vma_manager.h>
43 #include <drm/drm_gem.h>
44 #include <drm/drm_print.h>
45 #include "drm_internal.h"
49 * This file provides some of the base ioctls and library routines for
50 * the graphics memory manager implemented by each device driver.
52 * Because various devices have different requirements in terms of
53 * synchronization and migration strategies, implementing that is left up to
54 * the driver, and all that the general API provides should be generic --
55 * allocating objects, reading/writing data with the cpu, freeing objects.
56 * Even there, platform-dependent optimizations for reading/writing data with
57 * the CPU mean we'll likely hook those out to driver-specific calls. However,
58 * the DRI2 implementation wants to have at least allocate/mmap be generic.
60 * The goal was to have swap-backed object allocation managed through
61 * struct file. However, file descriptors as handles to a struct file have
63 * - Process limits prevent more than 1024 or so being used at a time by
65 * - Inability to allocate high fds will aggravate the X Server's select()
66 * handling, and likely that of many GL client applications as well.
68 * This led to a plan of using our own integer IDs (called handles, following
69 * DRM terminology) to mimic fds, and implement the fd syscalls we need as
70 * ioctls. The objects themselves will still include the struct file so
71 * that we can transition to fds if the required kernel infrastructure shows
72 * up at a later date, and as our interface with shmfs for memory allocation.
76 * drm_gem_init - Initialize the GEM device fields
77 * @dev: drm_devic structure to initialize
80 drm_gem_init(struct drm_device *dev)
82 struct drm_vma_offset_manager *vma_offset_manager;
84 mutex_init(&dev->object_name_lock);
85 idr_init_base(&dev->object_name_idr, 1);
87 vma_offset_manager = kzalloc(sizeof(*vma_offset_manager), GFP_KERNEL);
88 if (!vma_offset_manager) {
89 DRM_ERROR("out of memory\n");
93 dev->vma_offset_manager = vma_offset_manager;
94 drm_vma_offset_manager_init(vma_offset_manager,
95 DRM_FILE_PAGE_OFFSET_START,
96 DRM_FILE_PAGE_OFFSET_SIZE);
102 drm_gem_destroy(struct drm_device *dev)
105 drm_vma_offset_manager_destroy(dev->vma_offset_manager);
106 kfree(dev->vma_offset_manager);
107 dev->vma_offset_manager = NULL;
111 * drm_gem_object_init - initialize an allocated shmem-backed GEM object
112 * @dev: drm_device the object should be initialized for
113 * @obj: drm_gem_object to initialize
116 * Initialize an already allocated GEM object of the specified size with
117 * shmfs backing store.
119 int drm_gem_object_init(struct drm_device *dev,
120 struct drm_gem_object *obj, size_t size)
124 drm_gem_private_object_init(dev, obj, size);
126 filp = shmem_file_setup("drm mm object", size, VM_NORESERVE);
128 return PTR_ERR(filp);
134 EXPORT_SYMBOL(drm_gem_object_init);
137 * drm_gem_private_object_init - initialize an allocated private GEM object
138 * @dev: drm_device the object should be initialized for
139 * @obj: drm_gem_object to initialize
142 * Initialize an already allocated GEM object of the specified size with
143 * no GEM provided backing store. Instead the caller is responsible for
144 * backing the object and handling it.
146 void drm_gem_private_object_init(struct drm_device *dev,
147 struct drm_gem_object *obj, size_t size)
149 BUG_ON((size & (PAGE_SIZE - 1)) != 0);
154 kref_init(&obj->refcount);
155 obj->handle_count = 0;
157 drm_vma_node_reset(&obj->vma_node);
159 EXPORT_SYMBOL(drm_gem_private_object_init);
162 drm_gem_remove_prime_handles(struct drm_gem_object *obj, struct drm_file *filp)
165 * Note: obj->dma_buf can't disappear as long as we still hold a
166 * handle reference in obj->handle_count.
168 mutex_lock(&filp->prime.lock);
170 drm_prime_remove_buf_handle_locked(&filp->prime,
173 mutex_unlock(&filp->prime.lock);
177 * drm_gem_object_handle_free - release resources bound to userspace handles
178 * @obj: GEM object to clean up.
180 * Called after the last handle to the object has been closed
182 * Removes any name for the object. Note that this must be
183 * called before drm_gem_object_free or we'll be touching
186 static void drm_gem_object_handle_free(struct drm_gem_object *obj)
188 struct drm_device *dev = obj->dev;
190 /* Remove any name for this object */
192 idr_remove(&dev->object_name_idr, obj->name);
197 static void drm_gem_object_exported_dma_buf_free(struct drm_gem_object *obj)
199 /* Unbreak the reference cycle if we have an exported dma_buf. */
201 dma_buf_put(obj->dma_buf);
207 drm_gem_object_handle_put_unlocked(struct drm_gem_object *obj)
209 struct drm_device *dev = obj->dev;
212 if (WARN_ON(obj->handle_count == 0))
216 * Must bump handle count first as this may be the last
217 * ref, in which case the object would disappear before we
221 mutex_lock(&dev->object_name_lock);
222 if (--obj->handle_count == 0) {
223 drm_gem_object_handle_free(obj);
224 drm_gem_object_exported_dma_buf_free(obj);
227 mutex_unlock(&dev->object_name_lock);
230 drm_gem_object_put_unlocked(obj);
234 * Called at device or object close to release the file's
235 * handle references on objects.
238 drm_gem_object_release_handle(int id, void *ptr, void *data)
240 struct drm_file *file_priv = data;
241 struct drm_gem_object *obj = ptr;
242 struct drm_device *dev = obj->dev;
244 if (obj->funcs && obj->funcs->close)
245 obj->funcs->close(obj, file_priv);
246 else if (dev->driver->gem_close_object)
247 dev->driver->gem_close_object(obj, file_priv);
249 if (drm_core_check_feature(dev, DRIVER_PRIME))
250 drm_gem_remove_prime_handles(obj, file_priv);
251 drm_vma_node_revoke(&obj->vma_node, file_priv);
253 drm_gem_object_handle_put_unlocked(obj);
259 * drm_gem_handle_delete - deletes the given file-private handle
260 * @filp: drm file-private structure to use for the handle look up
261 * @handle: userspace handle to delete
263 * Removes the GEM handle from the @filp lookup table which has been added with
264 * drm_gem_handle_create(). If this is the last handle also cleans up linked
265 * resources like GEM names.
268 drm_gem_handle_delete(struct drm_file *filp, u32 handle)
270 struct drm_gem_object *obj;
272 spin_lock(&filp->table_lock);
274 /* Check if we currently have a reference on the object */
275 obj = idr_replace(&filp->object_idr, NULL, handle);
276 spin_unlock(&filp->table_lock);
277 if (IS_ERR_OR_NULL(obj))
280 /* Release driver's reference and decrement refcount. */
281 drm_gem_object_release_handle(handle, obj, filp);
283 /* And finally make the handle available for future allocations. */
284 spin_lock(&filp->table_lock);
285 idr_remove(&filp->object_idr, handle);
286 spin_unlock(&filp->table_lock);
290 EXPORT_SYMBOL(drm_gem_handle_delete);
293 * drm_gem_dumb_map_offset - return the fake mmap offset for a gem object
294 * @file: drm file-private structure containing the gem object
295 * @dev: corresponding drm_device
296 * @handle: gem object handle
297 * @offset: return location for the fake mmap offset
299 * This implements the &drm_driver.dumb_map_offset kms driver callback for
300 * drivers which use gem to manage their backing storage.
303 * 0 on success or a negative error code on failure.
305 int drm_gem_dumb_map_offset(struct drm_file *file, struct drm_device *dev,
306 u32 handle, u64 *offset)
308 struct drm_gem_object *obj;
311 obj = drm_gem_object_lookup(file, handle);
315 /* Don't allow imported objects to be mapped */
316 if (obj->import_attach) {
321 ret = drm_gem_create_mmap_offset(obj);
325 *offset = drm_vma_node_offset_addr(&obj->vma_node);
327 drm_gem_object_put_unlocked(obj);
331 EXPORT_SYMBOL_GPL(drm_gem_dumb_map_offset);
334 * drm_gem_dumb_destroy - dumb fb callback helper for gem based drivers
335 * @file: drm file-private structure to remove the dumb handle from
336 * @dev: corresponding drm_device
337 * @handle: the dumb handle to remove
339 * This implements the &drm_driver.dumb_destroy kms driver callback for drivers
340 * which use gem to manage their backing storage.
342 int drm_gem_dumb_destroy(struct drm_file *file,
343 struct drm_device *dev,
346 return drm_gem_handle_delete(file, handle);
348 EXPORT_SYMBOL(drm_gem_dumb_destroy);
351 * drm_gem_handle_create_tail - internal functions to create a handle
352 * @file_priv: drm file-private structure to register the handle for
353 * @obj: object to register
354 * @handlep: pointer to return the created handle to the caller
356 * This expects the &drm_device.object_name_lock to be held already and will
357 * drop it before returning. Used to avoid races in establishing new handles
358 * when importing an object from either an flink name or a dma-buf.
360 * Handles must be release again through drm_gem_handle_delete(). This is done
361 * when userspace closes @file_priv for all attached handles, or through the
362 * GEM_CLOSE ioctl for individual handles.
365 drm_gem_handle_create_tail(struct drm_file *file_priv,
366 struct drm_gem_object *obj,
369 struct drm_device *dev = obj->dev;
373 WARN_ON(!mutex_is_locked(&dev->object_name_lock));
374 if (obj->handle_count++ == 0)
375 drm_gem_object_get(obj);
378 * Get the user-visible handle using idr. Preload and perform
379 * allocation under our spinlock.
381 idr_preload(GFP_KERNEL);
382 spin_lock(&file_priv->table_lock);
384 ret = idr_alloc(&file_priv->object_idr, obj, 1, 0, GFP_NOWAIT);
386 spin_unlock(&file_priv->table_lock);
389 mutex_unlock(&dev->object_name_lock);
395 ret = drm_vma_node_allow(&obj->vma_node, file_priv);
399 if (obj->funcs && obj->funcs->open) {
400 ret = obj->funcs->open(obj, file_priv);
403 } else if (dev->driver->gem_open_object) {
404 ret = dev->driver->gem_open_object(obj, file_priv);
413 drm_vma_node_revoke(&obj->vma_node, file_priv);
415 spin_lock(&file_priv->table_lock);
416 idr_remove(&file_priv->object_idr, handle);
417 spin_unlock(&file_priv->table_lock);
419 drm_gem_object_handle_put_unlocked(obj);
424 * drm_gem_handle_create - create a gem handle for an object
425 * @file_priv: drm file-private structure to register the handle for
426 * @obj: object to register
427 * @handlep: pionter to return the created handle to the caller
429 * Create a handle for this object. This adds a handle reference to the object,
430 * which includes a regular reference count. Callers will likely want to
431 * dereference the object afterwards.
433 * Since this publishes @obj to userspace it must be fully set up by this point,
434 * drivers must call this last in their buffer object creation callbacks.
436 int drm_gem_handle_create(struct drm_file *file_priv,
437 struct drm_gem_object *obj,
440 mutex_lock(&obj->dev->object_name_lock);
442 return drm_gem_handle_create_tail(file_priv, obj, handlep);
444 EXPORT_SYMBOL(drm_gem_handle_create);
448 * drm_gem_free_mmap_offset - release a fake mmap offset for an object
449 * @obj: obj in question
451 * This routine frees fake offsets allocated by drm_gem_create_mmap_offset().
453 * Note that drm_gem_object_release() already calls this function, so drivers
454 * don't have to take care of releasing the mmap offset themselves when freeing
458 drm_gem_free_mmap_offset(struct drm_gem_object *obj)
460 struct drm_device *dev = obj->dev;
462 drm_vma_offset_remove(dev->vma_offset_manager, &obj->vma_node);
464 EXPORT_SYMBOL(drm_gem_free_mmap_offset);
467 * drm_gem_create_mmap_offset_size - create a fake mmap offset for an object
468 * @obj: obj in question
469 * @size: the virtual size
471 * GEM memory mapping works by handing back to userspace a fake mmap offset
472 * it can use in a subsequent mmap(2) call. The DRM core code then looks
473 * up the object based on the offset and sets up the various memory mapping
476 * This routine allocates and attaches a fake offset for @obj, in cases where
477 * the virtual size differs from the physical size (ie. &drm_gem_object.size).
478 * Otherwise just use drm_gem_create_mmap_offset().
480 * This function is idempotent and handles an already allocated mmap offset
481 * transparently. Drivers do not need to check for this case.
484 drm_gem_create_mmap_offset_size(struct drm_gem_object *obj, size_t size)
486 struct drm_device *dev = obj->dev;
488 return drm_vma_offset_add(dev->vma_offset_manager, &obj->vma_node,
491 EXPORT_SYMBOL(drm_gem_create_mmap_offset_size);
494 * drm_gem_create_mmap_offset - create a fake mmap offset for an object
495 * @obj: obj in question
497 * GEM memory mapping works by handing back to userspace a fake mmap offset
498 * it can use in a subsequent mmap(2) call. The DRM core code then looks
499 * up the object based on the offset and sets up the various memory mapping
502 * This routine allocates and attaches a fake offset for @obj.
504 * Drivers can call drm_gem_free_mmap_offset() before freeing @obj to release
505 * the fake offset again.
507 int drm_gem_create_mmap_offset(struct drm_gem_object *obj)
509 return drm_gem_create_mmap_offset_size(obj, obj->size);
511 EXPORT_SYMBOL(drm_gem_create_mmap_offset);
514 * Move pages to appropriate lru and release the pagevec, decrementing the
515 * ref count of those pages.
517 static void drm_gem_check_release_pagevec(struct pagevec *pvec)
519 check_move_unevictable_pages(pvec);
520 __pagevec_release(pvec);
525 * drm_gem_get_pages - helper to allocate backing pages for a GEM object
527 * @obj: obj in question
529 * This reads the page-array of the shmem-backing storage of the given gem
530 * object. An array of pages is returned. If a page is not allocated or
531 * swapped-out, this will allocate/swap-in the required pages. Note that the
532 * whole object is covered by the page-array and pinned in memory.
534 * Use drm_gem_put_pages() to release the array and unpin all pages.
536 * This uses the GFP-mask set on the shmem-mapping (see mapping_set_gfp_mask()).
537 * If you require other GFP-masks, you have to do those allocations yourself.
539 * Note that you are not allowed to change gfp-zones during runtime. That is,
540 * shmem_read_mapping_page_gfp() must be called with the same gfp_zone(gfp) as
541 * set during initialization. If you have special zone constraints, set them
542 * after drm_gem_object_init() via mapping_set_gfp_mask(). shmem-core takes care
543 * to keep pages in the required zone during swap-in.
545 struct page **drm_gem_get_pages(struct drm_gem_object *obj)
547 struct address_space *mapping;
548 struct page *p, **pages;
552 /* This is the shared memory object that backs the GEM resource */
553 mapping = obj->filp->f_mapping;
555 /* We already BUG_ON() for non-page-aligned sizes in
556 * drm_gem_object_init(), so we should never hit this unless
557 * driver author is doing something really wrong:
559 WARN_ON((obj->size & (PAGE_SIZE - 1)) != 0);
561 npages = obj->size >> PAGE_SHIFT;
563 pages = kvmalloc_array(npages, sizeof(struct page *), GFP_KERNEL);
565 return ERR_PTR(-ENOMEM);
567 mapping_set_unevictable(mapping);
569 for (i = 0; i < npages; i++) {
570 p = shmem_read_mapping_page(mapping, i);
575 /* Make sure shmem keeps __GFP_DMA32 allocated pages in the
576 * correct region during swapin. Note that this requires
577 * __GFP_DMA32 to be set in mapping_gfp_mask(inode->i_mapping)
578 * so shmem can relocate pages during swapin if required.
580 BUG_ON(mapping_gfp_constraint(mapping, __GFP_DMA32) &&
581 (page_to_pfn(p) >= 0x00100000UL));
587 mapping_clear_unevictable(mapping);
590 if (!pagevec_add(&pvec, pages[i]))
591 drm_gem_check_release_pagevec(&pvec);
593 if (pagevec_count(&pvec))
594 drm_gem_check_release_pagevec(&pvec);
599 EXPORT_SYMBOL(drm_gem_get_pages);
602 * drm_gem_put_pages - helper to free backing pages for a GEM object
603 * @obj: obj in question
604 * @pages: pages to free
605 * @dirty: if true, pages will be marked as dirty
606 * @accessed: if true, the pages will be marked as accessed
608 void drm_gem_put_pages(struct drm_gem_object *obj, struct page **pages,
609 bool dirty, bool accessed)
612 struct address_space *mapping;
615 mapping = file_inode(obj->filp)->i_mapping;
616 mapping_clear_unevictable(mapping);
618 /* We already BUG_ON() for non-page-aligned sizes in
619 * drm_gem_object_init(), so we should never hit this unless
620 * driver author is doing something really wrong:
622 WARN_ON((obj->size & (PAGE_SIZE - 1)) != 0);
624 npages = obj->size >> PAGE_SHIFT;
627 for (i = 0; i < npages; i++) {
629 set_page_dirty(pages[i]);
632 mark_page_accessed(pages[i]);
634 /* Undo the reference we took when populating the table */
635 if (!pagevec_add(&pvec, pages[i]))
636 drm_gem_check_release_pagevec(&pvec);
638 if (pagevec_count(&pvec))
639 drm_gem_check_release_pagevec(&pvec);
643 EXPORT_SYMBOL(drm_gem_put_pages);
646 * drm_gem_object_lookup - look up a GEM object from its handle
647 * @filp: DRM file private date
648 * @handle: userspace handle
652 * A reference to the object named by the handle if such exists on @filp, NULL
655 struct drm_gem_object *
656 drm_gem_object_lookup(struct drm_file *filp, u32 handle)
658 struct drm_gem_object *obj;
660 spin_lock(&filp->table_lock);
662 /* Check if we currently have a reference on the object */
663 obj = idr_find(&filp->object_idr, handle);
665 drm_gem_object_get(obj);
667 spin_unlock(&filp->table_lock);
671 EXPORT_SYMBOL(drm_gem_object_lookup);
674 * drm_gem_close_ioctl - implementation of the GEM_CLOSE ioctl
677 * @file_priv: drm file-private structure
679 * Releases the handle to an mm object.
682 drm_gem_close_ioctl(struct drm_device *dev, void *data,
683 struct drm_file *file_priv)
685 struct drm_gem_close *args = data;
688 if (!drm_core_check_feature(dev, DRIVER_GEM))
691 ret = drm_gem_handle_delete(file_priv, args->handle);
697 * drm_gem_flink_ioctl - implementation of the GEM_FLINK ioctl
700 * @file_priv: drm file-private structure
702 * Create a global name for an object, returning the name.
704 * Note that the name does not hold a reference; when the object
705 * is freed, the name goes away.
708 drm_gem_flink_ioctl(struct drm_device *dev, void *data,
709 struct drm_file *file_priv)
711 struct drm_gem_flink *args = data;
712 struct drm_gem_object *obj;
715 if (!drm_core_check_feature(dev, DRIVER_GEM))
718 obj = drm_gem_object_lookup(file_priv, args->handle);
722 mutex_lock(&dev->object_name_lock);
723 /* prevent races with concurrent gem_close. */
724 if (obj->handle_count == 0) {
730 ret = idr_alloc(&dev->object_name_idr, obj, 1, 0, GFP_KERNEL);
737 args->name = (uint64_t) obj->name;
741 mutex_unlock(&dev->object_name_lock);
742 drm_gem_object_put_unlocked(obj);
747 * drm_gem_open - implementation of the GEM_OPEN ioctl
750 * @file_priv: drm file-private structure
752 * Open an object using the global name, returning a handle and the size.
754 * This handle (of course) holds a reference to the object, so the object
755 * will not go away until the handle is deleted.
758 drm_gem_open_ioctl(struct drm_device *dev, void *data,
759 struct drm_file *file_priv)
761 struct drm_gem_open *args = data;
762 struct drm_gem_object *obj;
766 if (!drm_core_check_feature(dev, DRIVER_GEM))
769 mutex_lock(&dev->object_name_lock);
770 obj = idr_find(&dev->object_name_idr, (int) args->name);
772 drm_gem_object_get(obj);
774 mutex_unlock(&dev->object_name_lock);
778 /* drm_gem_handle_create_tail unlocks dev->object_name_lock. */
779 ret = drm_gem_handle_create_tail(file_priv, obj, &handle);
780 drm_gem_object_put_unlocked(obj);
784 args->handle = handle;
785 args->size = obj->size;
791 * gem_gem_open - initalizes GEM file-private structures at devnode open time
792 * @dev: drm_device which is being opened by userspace
793 * @file_private: drm file-private structure to set up
795 * Called at device open time, sets up the structure for handling refcounting
799 drm_gem_open(struct drm_device *dev, struct drm_file *file_private)
801 idr_init_base(&file_private->object_idr, 1);
802 spin_lock_init(&file_private->table_lock);
806 * drm_gem_release - release file-private GEM resources
807 * @dev: drm_device which is being closed by userspace
808 * @file_private: drm file-private structure to clean up
810 * Called at close time when the filp is going away.
812 * Releases any remaining references on objects by this filp.
815 drm_gem_release(struct drm_device *dev, struct drm_file *file_private)
817 idr_for_each(&file_private->object_idr,
818 &drm_gem_object_release_handle, file_private);
819 idr_destroy(&file_private->object_idr);
823 * drm_gem_object_release - release GEM buffer object resources
824 * @obj: GEM buffer object
826 * This releases any structures and resources used by @obj and is the invers of
827 * drm_gem_object_init().
830 drm_gem_object_release(struct drm_gem_object *obj)
832 WARN_ON(obj->dma_buf);
837 drm_gem_free_mmap_offset(obj);
839 EXPORT_SYMBOL(drm_gem_object_release);
842 * drm_gem_object_free - free a GEM object
843 * @kref: kref of the object to free
845 * Called after the last reference to the object has been lost.
846 * Must be called holding &drm_device.struct_mutex.
851 drm_gem_object_free(struct kref *kref)
853 struct drm_gem_object *obj =
854 container_of(kref, struct drm_gem_object, refcount);
855 struct drm_device *dev = obj->dev;
858 obj->funcs->free(obj);
859 } else if (dev->driver->gem_free_object_unlocked) {
860 dev->driver->gem_free_object_unlocked(obj);
861 } else if (dev->driver->gem_free_object) {
862 WARN_ON(!mutex_is_locked(&dev->struct_mutex));
864 dev->driver->gem_free_object(obj);
867 EXPORT_SYMBOL(drm_gem_object_free);
870 * drm_gem_object_put_unlocked - drop a GEM buffer object reference
871 * @obj: GEM buffer object
873 * This releases a reference to @obj. Callers must not hold the
874 * &drm_device.struct_mutex lock when calling this function.
876 * See also __drm_gem_object_put().
879 drm_gem_object_put_unlocked(struct drm_gem_object *obj)
881 struct drm_device *dev;
888 if (dev->driver->gem_free_object) {
889 might_lock(&dev->struct_mutex);
890 if (kref_put_mutex(&obj->refcount, drm_gem_object_free,
892 mutex_unlock(&dev->struct_mutex);
894 kref_put(&obj->refcount, drm_gem_object_free);
897 EXPORT_SYMBOL(drm_gem_object_put_unlocked);
900 * drm_gem_object_put - release a GEM buffer object reference
901 * @obj: GEM buffer object
903 * This releases a reference to @obj. Callers must hold the
904 * &drm_device.struct_mutex lock when calling this function, even when the
905 * driver doesn't use &drm_device.struct_mutex for anything.
907 * For drivers not encumbered with legacy locking use
908 * drm_gem_object_put_unlocked() instead.
911 drm_gem_object_put(struct drm_gem_object *obj)
914 WARN_ON(!mutex_is_locked(&obj->dev->struct_mutex));
916 kref_put(&obj->refcount, drm_gem_object_free);
919 EXPORT_SYMBOL(drm_gem_object_put);
922 * drm_gem_vm_open - vma->ops->open implementation for GEM
923 * @vma: VM area structure
925 * This function implements the #vm_operations_struct open() callback for GEM
926 * drivers. This must be used together with drm_gem_vm_close().
928 void drm_gem_vm_open(struct vm_area_struct *vma)
930 struct drm_gem_object *obj = vma->vm_private_data;
932 drm_gem_object_get(obj);
934 EXPORT_SYMBOL(drm_gem_vm_open);
937 * drm_gem_vm_close - vma->ops->close implementation for GEM
938 * @vma: VM area structure
940 * This function implements the #vm_operations_struct close() callback for GEM
941 * drivers. This must be used together with drm_gem_vm_open().
943 void drm_gem_vm_close(struct vm_area_struct *vma)
945 struct drm_gem_object *obj = vma->vm_private_data;
947 drm_gem_object_put_unlocked(obj);
949 EXPORT_SYMBOL(drm_gem_vm_close);
952 * drm_gem_mmap_obj - memory map a GEM object
953 * @obj: the GEM object to map
954 * @obj_size: the object size to be mapped, in bytes
955 * @vma: VMA for the area to be mapped
957 * Set up the VMA to prepare mapping of the GEM object using the gem_vm_ops
958 * provided by the driver. Depending on their requirements, drivers can either
959 * provide a fault handler in their gem_vm_ops (in which case any accesses to
960 * the object will be trapped, to perform migration, GTT binding, surface
961 * register allocation, or performance monitoring), or mmap the buffer memory
962 * synchronously after calling drm_gem_mmap_obj.
964 * This function is mainly intended to implement the DMABUF mmap operation, when
965 * the GEM object is not looked up based on its fake offset. To implement the
966 * DRM mmap operation, drivers should use the drm_gem_mmap() function.
968 * drm_gem_mmap_obj() assumes the user is granted access to the buffer while
969 * drm_gem_mmap() prevents unprivileged users from mapping random objects. So
970 * callers must verify access restrictions before calling this helper.
972 * Return 0 or success or -EINVAL if the object size is smaller than the VMA
973 * size, or if no gem_vm_ops are provided.
975 int drm_gem_mmap_obj(struct drm_gem_object *obj, unsigned long obj_size,
976 struct vm_area_struct *vma)
978 struct drm_device *dev = obj->dev;
980 /* Check for valid size. */
981 if (obj_size < vma->vm_end - vma->vm_start)
984 if (obj->funcs && obj->funcs->vm_ops)
985 vma->vm_ops = obj->funcs->vm_ops;
986 else if (dev->driver->gem_vm_ops)
987 vma->vm_ops = dev->driver->gem_vm_ops;
991 vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP;
992 vma->vm_private_data = obj;
993 vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags));
994 vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
996 /* Take a ref for this mapping of the object, so that the fault
997 * handler can dereference the mmap offset's pointer to the object.
998 * This reference is cleaned up by the corresponding vm_close
999 * (which should happen whether the vma was created by this call, or
1000 * by a vm_open due to mremap or partial unmap or whatever).
1002 drm_gem_object_get(obj);
1006 EXPORT_SYMBOL(drm_gem_mmap_obj);
1009 * drm_gem_mmap - memory map routine for GEM objects
1010 * @filp: DRM file pointer
1011 * @vma: VMA for the area to be mapped
1013 * If a driver supports GEM object mapping, mmap calls on the DRM file
1014 * descriptor will end up here.
1016 * Look up the GEM object based on the offset passed in (vma->vm_pgoff will
1017 * contain the fake offset we created when the GTT map ioctl was called on
1018 * the object) and map it with a call to drm_gem_mmap_obj().
1020 * If the caller is not granted access to the buffer object, the mmap will fail
1021 * with EACCES. Please see the vma manager for more information.
1023 int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma)
1025 struct drm_file *priv = filp->private_data;
1026 struct drm_device *dev = priv->minor->dev;
1027 struct drm_gem_object *obj = NULL;
1028 struct drm_vma_offset_node *node;
1031 if (drm_dev_is_unplugged(dev))
1034 drm_vma_offset_lock_lookup(dev->vma_offset_manager);
1035 node = drm_vma_offset_exact_lookup_locked(dev->vma_offset_manager,
1039 obj = container_of(node, struct drm_gem_object, vma_node);
1041 * When the object is being freed, after it hits 0-refcnt it
1042 * proceeds to tear down the object. In the process it will
1043 * attempt to remove the VMA offset and so acquire this
1044 * mgr->vm_lock. Therefore if we find an object with a 0-refcnt
1045 * that matches our range, we know it is in the process of being
1046 * destroyed and will be freed as soon as we release the lock -
1047 * so we have to check for the 0-refcnted object and treat it as
1050 if (!kref_get_unless_zero(&obj->refcount))
1053 drm_vma_offset_unlock_lookup(dev->vma_offset_manager);
1058 if (!drm_vma_node_is_allowed(node, priv)) {
1059 drm_gem_object_put_unlocked(obj);
1063 if (node->readonly) {
1064 if (vma->vm_flags & VM_WRITE) {
1065 drm_gem_object_put_unlocked(obj);
1069 vma->vm_flags &= ~VM_MAYWRITE;
1072 ret = drm_gem_mmap_obj(obj, drm_vma_node_size(node) << PAGE_SHIFT,
1075 drm_gem_object_put_unlocked(obj);
1079 EXPORT_SYMBOL(drm_gem_mmap);
1081 void drm_gem_print_info(struct drm_printer *p, unsigned int indent,
1082 const struct drm_gem_object *obj)
1084 drm_printf_indent(p, indent, "name=%d\n", obj->name);
1085 drm_printf_indent(p, indent, "refcount=%u\n",
1086 kref_read(&obj->refcount));
1087 drm_printf_indent(p, indent, "start=%08lx\n",
1088 drm_vma_node_start(&obj->vma_node));
1089 drm_printf_indent(p, indent, "size=%zu\n", obj->size);
1090 drm_printf_indent(p, indent, "imported=%s\n",
1091 obj->import_attach ? "yes" : "no");
1093 if (obj->funcs && obj->funcs->print_info)
1094 obj->funcs->print_info(p, indent, obj);
1095 else if (obj->dev->driver->gem_print_info)
1096 obj->dev->driver->gem_print_info(p, indent, obj);
1100 * drm_gem_pin - Pin backing buffer in memory
1103 * Make sure the backing buffer is pinned in memory.
1106 * 0 on success or a negative error code on failure.
1108 int drm_gem_pin(struct drm_gem_object *obj)
1110 if (obj->funcs && obj->funcs->pin)
1111 return obj->funcs->pin(obj);
1112 else if (obj->dev->driver->gem_prime_pin)
1113 return obj->dev->driver->gem_prime_pin(obj);
1117 EXPORT_SYMBOL(drm_gem_pin);
1120 * drm_gem_unpin - Unpin backing buffer from memory
1123 * Relax the requirement that the backing buffer is pinned in memory.
1125 void drm_gem_unpin(struct drm_gem_object *obj)
1127 if (obj->funcs && obj->funcs->unpin)
1128 obj->funcs->unpin(obj);
1129 else if (obj->dev->driver->gem_prime_unpin)
1130 obj->dev->driver->gem_prime_unpin(obj);
1132 EXPORT_SYMBOL(drm_gem_unpin);
1135 * drm_gem_vmap - Map buffer into kernel virtual address space
1139 * A virtual pointer to a newly created GEM object or an ERR_PTR-encoded negative
1140 * error code on failure.
1142 void *drm_gem_vmap(struct drm_gem_object *obj)
1146 if (obj->funcs && obj->funcs->vmap)
1147 vaddr = obj->funcs->vmap(obj);
1148 else if (obj->dev->driver->gem_prime_vmap)
1149 vaddr = obj->dev->driver->gem_prime_vmap(obj);
1151 vaddr = ERR_PTR(-EOPNOTSUPP);
1154 vaddr = ERR_PTR(-ENOMEM);
1158 EXPORT_SYMBOL(drm_gem_vmap);
1161 * drm_gem_vunmap - Remove buffer mapping from kernel virtual address space
1163 * @vaddr: Virtual address (can be NULL)
1165 void drm_gem_vunmap(struct drm_gem_object *obj, void *vaddr)
1170 if (obj->funcs && obj->funcs->vunmap)
1171 obj->funcs->vunmap(obj, vaddr);
1172 else if (obj->dev->driver->gem_prime_vunmap)
1173 obj->dev->driver->gem_prime_vunmap(obj, vaddr);
1175 EXPORT_SYMBOL(drm_gem_vunmap);