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 reservation_object_init(&obj->_resv);
159 obj->resv = &obj->_resv;
161 drm_vma_node_reset(&obj->vma_node);
163 EXPORT_SYMBOL(drm_gem_private_object_init);
166 drm_gem_remove_prime_handles(struct drm_gem_object *obj, struct drm_file *filp)
169 * Note: obj->dma_buf can't disappear as long as we still hold a
170 * handle reference in obj->handle_count.
172 mutex_lock(&filp->prime.lock);
174 drm_prime_remove_buf_handle_locked(&filp->prime,
177 mutex_unlock(&filp->prime.lock);
181 * drm_gem_object_handle_free - release resources bound to userspace handles
182 * @obj: GEM object to clean up.
184 * Called after the last handle to the object has been closed
186 * Removes any name for the object. Note that this must be
187 * called before drm_gem_object_free or we'll be touching
190 static void drm_gem_object_handle_free(struct drm_gem_object *obj)
192 struct drm_device *dev = obj->dev;
194 /* Remove any name for this object */
196 idr_remove(&dev->object_name_idr, obj->name);
201 static void drm_gem_object_exported_dma_buf_free(struct drm_gem_object *obj)
203 /* Unbreak the reference cycle if we have an exported dma_buf. */
205 dma_buf_put(obj->dma_buf);
211 drm_gem_object_handle_put_unlocked(struct drm_gem_object *obj)
213 struct drm_device *dev = obj->dev;
216 if (WARN_ON(obj->handle_count == 0))
220 * Must bump handle count first as this may be the last
221 * ref, in which case the object would disappear before we
225 mutex_lock(&dev->object_name_lock);
226 if (--obj->handle_count == 0) {
227 drm_gem_object_handle_free(obj);
228 drm_gem_object_exported_dma_buf_free(obj);
231 mutex_unlock(&dev->object_name_lock);
234 drm_gem_object_put_unlocked(obj);
238 * Called at device or object close to release the file's
239 * handle references on objects.
242 drm_gem_object_release_handle(int id, void *ptr, void *data)
244 struct drm_file *file_priv = data;
245 struct drm_gem_object *obj = ptr;
246 struct drm_device *dev = obj->dev;
248 if (obj->funcs && obj->funcs->close)
249 obj->funcs->close(obj, file_priv);
250 else if (dev->driver->gem_close_object)
251 dev->driver->gem_close_object(obj, file_priv);
253 if (drm_core_check_feature(dev, DRIVER_PRIME))
254 drm_gem_remove_prime_handles(obj, file_priv);
255 drm_vma_node_revoke(&obj->vma_node, file_priv);
257 drm_gem_object_handle_put_unlocked(obj);
263 * drm_gem_handle_delete - deletes the given file-private handle
264 * @filp: drm file-private structure to use for the handle look up
265 * @handle: userspace handle to delete
267 * Removes the GEM handle from the @filp lookup table which has been added with
268 * drm_gem_handle_create(). If this is the last handle also cleans up linked
269 * resources like GEM names.
272 drm_gem_handle_delete(struct drm_file *filp, u32 handle)
274 struct drm_gem_object *obj;
276 spin_lock(&filp->table_lock);
278 /* Check if we currently have a reference on the object */
279 obj = idr_replace(&filp->object_idr, NULL, handle);
280 spin_unlock(&filp->table_lock);
281 if (IS_ERR_OR_NULL(obj))
284 /* Release driver's reference and decrement refcount. */
285 drm_gem_object_release_handle(handle, obj, filp);
287 /* And finally make the handle available for future allocations. */
288 spin_lock(&filp->table_lock);
289 idr_remove(&filp->object_idr, handle);
290 spin_unlock(&filp->table_lock);
294 EXPORT_SYMBOL(drm_gem_handle_delete);
297 * drm_gem_dumb_map_offset - return the fake mmap offset for a gem object
298 * @file: drm file-private structure containing the gem object
299 * @dev: corresponding drm_device
300 * @handle: gem object handle
301 * @offset: return location for the fake mmap offset
303 * This implements the &drm_driver.dumb_map_offset kms driver callback for
304 * drivers which use gem to manage their backing storage.
307 * 0 on success or a negative error code on failure.
309 int drm_gem_dumb_map_offset(struct drm_file *file, struct drm_device *dev,
310 u32 handle, u64 *offset)
312 struct drm_gem_object *obj;
315 obj = drm_gem_object_lookup(file, handle);
319 /* Don't allow imported objects to be mapped */
320 if (obj->import_attach) {
325 ret = drm_gem_create_mmap_offset(obj);
329 *offset = drm_vma_node_offset_addr(&obj->vma_node);
331 drm_gem_object_put_unlocked(obj);
335 EXPORT_SYMBOL_GPL(drm_gem_dumb_map_offset);
338 * drm_gem_dumb_destroy - dumb fb callback helper for gem based drivers
339 * @file: drm file-private structure to remove the dumb handle from
340 * @dev: corresponding drm_device
341 * @handle: the dumb handle to remove
343 * This implements the &drm_driver.dumb_destroy kms driver callback for drivers
344 * which use gem to manage their backing storage.
346 int drm_gem_dumb_destroy(struct drm_file *file,
347 struct drm_device *dev,
350 return drm_gem_handle_delete(file, handle);
352 EXPORT_SYMBOL(drm_gem_dumb_destroy);
355 * drm_gem_handle_create_tail - internal functions to create a handle
356 * @file_priv: drm file-private structure to register the handle for
357 * @obj: object to register
358 * @handlep: pointer to return the created handle to the caller
360 * This expects the &drm_device.object_name_lock to be held already and will
361 * drop it before returning. Used to avoid races in establishing new handles
362 * when importing an object from either an flink name or a dma-buf.
364 * Handles must be release again through drm_gem_handle_delete(). This is done
365 * when userspace closes @file_priv for all attached handles, or through the
366 * GEM_CLOSE ioctl for individual handles.
369 drm_gem_handle_create_tail(struct drm_file *file_priv,
370 struct drm_gem_object *obj,
373 struct drm_device *dev = obj->dev;
377 WARN_ON(!mutex_is_locked(&dev->object_name_lock));
378 if (obj->handle_count++ == 0)
379 drm_gem_object_get(obj);
382 * Get the user-visible handle using idr. Preload and perform
383 * allocation under our spinlock.
385 idr_preload(GFP_KERNEL);
386 spin_lock(&file_priv->table_lock);
388 ret = idr_alloc(&file_priv->object_idr, obj, 1, 0, GFP_NOWAIT);
390 spin_unlock(&file_priv->table_lock);
393 mutex_unlock(&dev->object_name_lock);
399 ret = drm_vma_node_allow(&obj->vma_node, file_priv);
403 if (obj->funcs && obj->funcs->open) {
404 ret = obj->funcs->open(obj, file_priv);
407 } else if (dev->driver->gem_open_object) {
408 ret = dev->driver->gem_open_object(obj, file_priv);
417 drm_vma_node_revoke(&obj->vma_node, file_priv);
419 spin_lock(&file_priv->table_lock);
420 idr_remove(&file_priv->object_idr, handle);
421 spin_unlock(&file_priv->table_lock);
423 drm_gem_object_handle_put_unlocked(obj);
428 * drm_gem_handle_create - create a gem handle for an object
429 * @file_priv: drm file-private structure to register the handle for
430 * @obj: object to register
431 * @handlep: pionter to return the created handle to the caller
433 * Create a handle for this object. This adds a handle reference to the object,
434 * which includes a regular reference count. Callers will likely want to
435 * dereference the object afterwards.
437 * Since this publishes @obj to userspace it must be fully set up by this point,
438 * drivers must call this last in their buffer object creation callbacks.
440 int drm_gem_handle_create(struct drm_file *file_priv,
441 struct drm_gem_object *obj,
444 mutex_lock(&obj->dev->object_name_lock);
446 return drm_gem_handle_create_tail(file_priv, obj, handlep);
448 EXPORT_SYMBOL(drm_gem_handle_create);
452 * drm_gem_free_mmap_offset - release a fake mmap offset for an object
453 * @obj: obj in question
455 * This routine frees fake offsets allocated by drm_gem_create_mmap_offset().
457 * Note that drm_gem_object_release() already calls this function, so drivers
458 * don't have to take care of releasing the mmap offset themselves when freeing
462 drm_gem_free_mmap_offset(struct drm_gem_object *obj)
464 struct drm_device *dev = obj->dev;
466 drm_vma_offset_remove(dev->vma_offset_manager, &obj->vma_node);
468 EXPORT_SYMBOL(drm_gem_free_mmap_offset);
471 * drm_gem_create_mmap_offset_size - create a fake mmap offset for an object
472 * @obj: obj in question
473 * @size: the virtual size
475 * GEM memory mapping works by handing back to userspace a fake mmap offset
476 * it can use in a subsequent mmap(2) call. The DRM core code then looks
477 * up the object based on the offset and sets up the various memory mapping
480 * This routine allocates and attaches a fake offset for @obj, in cases where
481 * the virtual size differs from the physical size (ie. &drm_gem_object.size).
482 * Otherwise just use drm_gem_create_mmap_offset().
484 * This function is idempotent and handles an already allocated mmap offset
485 * transparently. Drivers do not need to check for this case.
488 drm_gem_create_mmap_offset_size(struct drm_gem_object *obj, size_t size)
490 struct drm_device *dev = obj->dev;
492 return drm_vma_offset_add(dev->vma_offset_manager, &obj->vma_node,
495 EXPORT_SYMBOL(drm_gem_create_mmap_offset_size);
498 * drm_gem_create_mmap_offset - create a fake mmap offset for an object
499 * @obj: obj in question
501 * GEM memory mapping works by handing back to userspace a fake mmap offset
502 * it can use in a subsequent mmap(2) call. The DRM core code then looks
503 * up the object based on the offset and sets up the various memory mapping
506 * This routine allocates and attaches a fake offset for @obj.
508 * Drivers can call drm_gem_free_mmap_offset() before freeing @obj to release
509 * the fake offset again.
511 int drm_gem_create_mmap_offset(struct drm_gem_object *obj)
513 return drm_gem_create_mmap_offset_size(obj, obj->size);
515 EXPORT_SYMBOL(drm_gem_create_mmap_offset);
518 * Move pages to appropriate lru and release the pagevec, decrementing the
519 * ref count of those pages.
521 static void drm_gem_check_release_pagevec(struct pagevec *pvec)
523 check_move_unevictable_pages(pvec);
524 __pagevec_release(pvec);
529 * drm_gem_get_pages - helper to allocate backing pages for a GEM object
531 * @obj: obj in question
533 * This reads the page-array of the shmem-backing storage of the given gem
534 * object. An array of pages is returned. If a page is not allocated or
535 * swapped-out, this will allocate/swap-in the required pages. Note that the
536 * whole object is covered by the page-array and pinned in memory.
538 * Use drm_gem_put_pages() to release the array and unpin all pages.
540 * This uses the GFP-mask set on the shmem-mapping (see mapping_set_gfp_mask()).
541 * If you require other GFP-masks, you have to do those allocations yourself.
543 * Note that you are not allowed to change gfp-zones during runtime. That is,
544 * shmem_read_mapping_page_gfp() must be called with the same gfp_zone(gfp) as
545 * set during initialization. If you have special zone constraints, set them
546 * after drm_gem_object_init() via mapping_set_gfp_mask(). shmem-core takes care
547 * to keep pages in the required zone during swap-in.
549 struct page **drm_gem_get_pages(struct drm_gem_object *obj)
551 struct address_space *mapping;
552 struct page *p, **pages;
556 /* This is the shared memory object that backs the GEM resource */
557 mapping = obj->filp->f_mapping;
559 /* We already BUG_ON() for non-page-aligned sizes in
560 * drm_gem_object_init(), so we should never hit this unless
561 * driver author is doing something really wrong:
563 WARN_ON((obj->size & (PAGE_SIZE - 1)) != 0);
565 npages = obj->size >> PAGE_SHIFT;
567 pages = kvmalloc_array(npages, sizeof(struct page *), GFP_KERNEL);
569 return ERR_PTR(-ENOMEM);
571 mapping_set_unevictable(mapping);
573 for (i = 0; i < npages; i++) {
574 p = shmem_read_mapping_page(mapping, i);
579 /* Make sure shmem keeps __GFP_DMA32 allocated pages in the
580 * correct region during swapin. Note that this requires
581 * __GFP_DMA32 to be set in mapping_gfp_mask(inode->i_mapping)
582 * so shmem can relocate pages during swapin if required.
584 BUG_ON(mapping_gfp_constraint(mapping, __GFP_DMA32) &&
585 (page_to_pfn(p) >= 0x00100000UL));
591 mapping_clear_unevictable(mapping);
594 if (!pagevec_add(&pvec, pages[i]))
595 drm_gem_check_release_pagevec(&pvec);
597 if (pagevec_count(&pvec))
598 drm_gem_check_release_pagevec(&pvec);
603 EXPORT_SYMBOL(drm_gem_get_pages);
606 * drm_gem_put_pages - helper to free backing pages for a GEM object
607 * @obj: obj in question
608 * @pages: pages to free
609 * @dirty: if true, pages will be marked as dirty
610 * @accessed: if true, the pages will be marked as accessed
612 void drm_gem_put_pages(struct drm_gem_object *obj, struct page **pages,
613 bool dirty, bool accessed)
616 struct address_space *mapping;
619 mapping = file_inode(obj->filp)->i_mapping;
620 mapping_clear_unevictable(mapping);
622 /* We already BUG_ON() for non-page-aligned sizes in
623 * drm_gem_object_init(), so we should never hit this unless
624 * driver author is doing something really wrong:
626 WARN_ON((obj->size & (PAGE_SIZE - 1)) != 0);
628 npages = obj->size >> PAGE_SHIFT;
631 for (i = 0; i < npages; i++) {
633 set_page_dirty(pages[i]);
636 mark_page_accessed(pages[i]);
638 /* Undo the reference we took when populating the table */
639 if (!pagevec_add(&pvec, pages[i]))
640 drm_gem_check_release_pagevec(&pvec);
642 if (pagevec_count(&pvec))
643 drm_gem_check_release_pagevec(&pvec);
647 EXPORT_SYMBOL(drm_gem_put_pages);
650 * drm_gem_object_lookup - look up a GEM object from its handle
651 * @filp: DRM file private date
652 * @handle: userspace handle
656 * A reference to the object named by the handle if such exists on @filp, NULL
659 struct drm_gem_object *
660 drm_gem_object_lookup(struct drm_file *filp, u32 handle)
662 struct drm_gem_object *obj;
664 spin_lock(&filp->table_lock);
666 /* Check if we currently have a reference on the object */
667 obj = idr_find(&filp->object_idr, handle);
669 drm_gem_object_get(obj);
671 spin_unlock(&filp->table_lock);
675 EXPORT_SYMBOL(drm_gem_object_lookup);
678 * drm_gem_reservation_object_wait - Wait on GEM object's reservation's objects
679 * shared and/or exclusive fences.
680 * @filep: DRM file private date
681 * @handle: userspace handle
682 * @wait_all: if true, wait on all fences, else wait on just exclusive fence
683 * @timeout: timeout value in jiffies or zero to return immediately
687 * Returns -ERESTARTSYS if interrupted, 0 if the wait timed out, or
688 * greater than 0 on success.
690 long drm_gem_reservation_object_wait(struct drm_file *filep, u32 handle,
691 bool wait_all, unsigned long timeout)
694 struct drm_gem_object *obj;
696 obj = drm_gem_object_lookup(filep, handle);
698 DRM_DEBUG("Failed to look up GEM BO %d\n", handle);
702 ret = reservation_object_wait_timeout_rcu(obj->resv, wait_all,
709 drm_gem_object_put_unlocked(obj);
713 EXPORT_SYMBOL(drm_gem_reservation_object_wait);
716 * drm_gem_close_ioctl - implementation of the GEM_CLOSE ioctl
719 * @file_priv: drm file-private structure
721 * Releases the handle to an mm object.
724 drm_gem_close_ioctl(struct drm_device *dev, void *data,
725 struct drm_file *file_priv)
727 struct drm_gem_close *args = data;
730 if (!drm_core_check_feature(dev, DRIVER_GEM))
733 ret = drm_gem_handle_delete(file_priv, args->handle);
739 * drm_gem_flink_ioctl - implementation of the GEM_FLINK ioctl
742 * @file_priv: drm file-private structure
744 * Create a global name for an object, returning the name.
746 * Note that the name does not hold a reference; when the object
747 * is freed, the name goes away.
750 drm_gem_flink_ioctl(struct drm_device *dev, void *data,
751 struct drm_file *file_priv)
753 struct drm_gem_flink *args = data;
754 struct drm_gem_object *obj;
757 if (!drm_core_check_feature(dev, DRIVER_GEM))
760 obj = drm_gem_object_lookup(file_priv, args->handle);
764 mutex_lock(&dev->object_name_lock);
765 /* prevent races with concurrent gem_close. */
766 if (obj->handle_count == 0) {
772 ret = idr_alloc(&dev->object_name_idr, obj, 1, 0, GFP_KERNEL);
779 args->name = (uint64_t) obj->name;
783 mutex_unlock(&dev->object_name_lock);
784 drm_gem_object_put_unlocked(obj);
789 * drm_gem_open - implementation of the GEM_OPEN ioctl
792 * @file_priv: drm file-private structure
794 * Open an object using the global name, returning a handle and the size.
796 * This handle (of course) holds a reference to the object, so the object
797 * will not go away until the handle is deleted.
800 drm_gem_open_ioctl(struct drm_device *dev, void *data,
801 struct drm_file *file_priv)
803 struct drm_gem_open *args = data;
804 struct drm_gem_object *obj;
808 if (!drm_core_check_feature(dev, DRIVER_GEM))
811 mutex_lock(&dev->object_name_lock);
812 obj = idr_find(&dev->object_name_idr, (int) args->name);
814 drm_gem_object_get(obj);
816 mutex_unlock(&dev->object_name_lock);
820 /* drm_gem_handle_create_tail unlocks dev->object_name_lock. */
821 ret = drm_gem_handle_create_tail(file_priv, obj, &handle);
822 drm_gem_object_put_unlocked(obj);
826 args->handle = handle;
827 args->size = obj->size;
833 * gem_gem_open - initalizes GEM file-private structures at devnode open time
834 * @dev: drm_device which is being opened by userspace
835 * @file_private: drm file-private structure to set up
837 * Called at device open time, sets up the structure for handling refcounting
841 drm_gem_open(struct drm_device *dev, struct drm_file *file_private)
843 idr_init_base(&file_private->object_idr, 1);
844 spin_lock_init(&file_private->table_lock);
848 * drm_gem_release - release file-private GEM resources
849 * @dev: drm_device which is being closed by userspace
850 * @file_private: drm file-private structure to clean up
852 * Called at close time when the filp is going away.
854 * Releases any remaining references on objects by this filp.
857 drm_gem_release(struct drm_device *dev, struct drm_file *file_private)
859 idr_for_each(&file_private->object_idr,
860 &drm_gem_object_release_handle, file_private);
861 idr_destroy(&file_private->object_idr);
865 * drm_gem_object_release - release GEM buffer object resources
866 * @obj: GEM buffer object
868 * This releases any structures and resources used by @obj and is the invers of
869 * drm_gem_object_init().
872 drm_gem_object_release(struct drm_gem_object *obj)
874 WARN_ON(obj->dma_buf);
879 reservation_object_fini(&obj->_resv);
880 drm_gem_free_mmap_offset(obj);
882 EXPORT_SYMBOL(drm_gem_object_release);
885 * drm_gem_object_free - free a GEM object
886 * @kref: kref of the object to free
888 * Called after the last reference to the object has been lost.
889 * Must be called holding &drm_device.struct_mutex.
894 drm_gem_object_free(struct kref *kref)
896 struct drm_gem_object *obj =
897 container_of(kref, struct drm_gem_object, refcount);
898 struct drm_device *dev = obj->dev;
901 obj->funcs->free(obj);
902 } else if (dev->driver->gem_free_object_unlocked) {
903 dev->driver->gem_free_object_unlocked(obj);
904 } else if (dev->driver->gem_free_object) {
905 WARN_ON(!mutex_is_locked(&dev->struct_mutex));
907 dev->driver->gem_free_object(obj);
910 EXPORT_SYMBOL(drm_gem_object_free);
913 * drm_gem_object_put_unlocked - drop a GEM buffer object reference
914 * @obj: GEM buffer object
916 * This releases a reference to @obj. Callers must not hold the
917 * &drm_device.struct_mutex lock when calling this function.
919 * See also __drm_gem_object_put().
922 drm_gem_object_put_unlocked(struct drm_gem_object *obj)
924 struct drm_device *dev;
931 if (dev->driver->gem_free_object) {
932 might_lock(&dev->struct_mutex);
933 if (kref_put_mutex(&obj->refcount, drm_gem_object_free,
935 mutex_unlock(&dev->struct_mutex);
937 kref_put(&obj->refcount, drm_gem_object_free);
940 EXPORT_SYMBOL(drm_gem_object_put_unlocked);
943 * drm_gem_object_put - release a GEM buffer object reference
944 * @obj: GEM buffer object
946 * This releases a reference to @obj. Callers must hold the
947 * &drm_device.struct_mutex lock when calling this function, even when the
948 * driver doesn't use &drm_device.struct_mutex for anything.
950 * For drivers not encumbered with legacy locking use
951 * drm_gem_object_put_unlocked() instead.
954 drm_gem_object_put(struct drm_gem_object *obj)
957 WARN_ON(!mutex_is_locked(&obj->dev->struct_mutex));
959 kref_put(&obj->refcount, drm_gem_object_free);
962 EXPORT_SYMBOL(drm_gem_object_put);
965 * drm_gem_vm_open - vma->ops->open implementation for GEM
966 * @vma: VM area structure
968 * This function implements the #vm_operations_struct open() callback for GEM
969 * drivers. This must be used together with drm_gem_vm_close().
971 void drm_gem_vm_open(struct vm_area_struct *vma)
973 struct drm_gem_object *obj = vma->vm_private_data;
975 drm_gem_object_get(obj);
977 EXPORT_SYMBOL(drm_gem_vm_open);
980 * drm_gem_vm_close - vma->ops->close implementation for GEM
981 * @vma: VM area structure
983 * This function implements the #vm_operations_struct close() callback for GEM
984 * drivers. This must be used together with drm_gem_vm_open().
986 void drm_gem_vm_close(struct vm_area_struct *vma)
988 struct drm_gem_object *obj = vma->vm_private_data;
990 drm_gem_object_put_unlocked(obj);
992 EXPORT_SYMBOL(drm_gem_vm_close);
995 * drm_gem_mmap_obj - memory map a GEM object
996 * @obj: the GEM object to map
997 * @obj_size: the object size to be mapped, in bytes
998 * @vma: VMA for the area to be mapped
1000 * Set up the VMA to prepare mapping of the GEM object using the gem_vm_ops
1001 * provided by the driver. Depending on their requirements, drivers can either
1002 * provide a fault handler in their gem_vm_ops (in which case any accesses to
1003 * the object will be trapped, to perform migration, GTT binding, surface
1004 * register allocation, or performance monitoring), or mmap the buffer memory
1005 * synchronously after calling drm_gem_mmap_obj.
1007 * This function is mainly intended to implement the DMABUF mmap operation, when
1008 * the GEM object is not looked up based on its fake offset. To implement the
1009 * DRM mmap operation, drivers should use the drm_gem_mmap() function.
1011 * drm_gem_mmap_obj() assumes the user is granted access to the buffer while
1012 * drm_gem_mmap() prevents unprivileged users from mapping random objects. So
1013 * callers must verify access restrictions before calling this helper.
1015 * Return 0 or success or -EINVAL if the object size is smaller than the VMA
1016 * size, or if no gem_vm_ops are provided.
1018 int drm_gem_mmap_obj(struct drm_gem_object *obj, unsigned long obj_size,
1019 struct vm_area_struct *vma)
1021 struct drm_device *dev = obj->dev;
1023 /* Check for valid size. */
1024 if (obj_size < vma->vm_end - vma->vm_start)
1027 if (obj->funcs && obj->funcs->vm_ops)
1028 vma->vm_ops = obj->funcs->vm_ops;
1029 else if (dev->driver->gem_vm_ops)
1030 vma->vm_ops = dev->driver->gem_vm_ops;
1034 vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP;
1035 vma->vm_private_data = obj;
1036 vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags));
1037 vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
1039 /* Take a ref for this mapping of the object, so that the fault
1040 * handler can dereference the mmap offset's pointer to the object.
1041 * This reference is cleaned up by the corresponding vm_close
1042 * (which should happen whether the vma was created by this call, or
1043 * by a vm_open due to mremap or partial unmap or whatever).
1045 drm_gem_object_get(obj);
1049 EXPORT_SYMBOL(drm_gem_mmap_obj);
1052 * drm_gem_mmap - memory map routine for GEM objects
1053 * @filp: DRM file pointer
1054 * @vma: VMA for the area to be mapped
1056 * If a driver supports GEM object mapping, mmap calls on the DRM file
1057 * descriptor will end up here.
1059 * Look up the GEM object based on the offset passed in (vma->vm_pgoff will
1060 * contain the fake offset we created when the GTT map ioctl was called on
1061 * the object) and map it with a call to drm_gem_mmap_obj().
1063 * If the caller is not granted access to the buffer object, the mmap will fail
1064 * with EACCES. Please see the vma manager for more information.
1066 int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma)
1068 struct drm_file *priv = filp->private_data;
1069 struct drm_device *dev = priv->minor->dev;
1070 struct drm_gem_object *obj = NULL;
1071 struct drm_vma_offset_node *node;
1074 if (drm_dev_is_unplugged(dev))
1077 drm_vma_offset_lock_lookup(dev->vma_offset_manager);
1078 node = drm_vma_offset_exact_lookup_locked(dev->vma_offset_manager,
1082 obj = container_of(node, struct drm_gem_object, vma_node);
1084 * When the object is being freed, after it hits 0-refcnt it
1085 * proceeds to tear down the object. In the process it will
1086 * attempt to remove the VMA offset and so acquire this
1087 * mgr->vm_lock. Therefore if we find an object with a 0-refcnt
1088 * that matches our range, we know it is in the process of being
1089 * destroyed and will be freed as soon as we release the lock -
1090 * so we have to check for the 0-refcnted object and treat it as
1093 if (!kref_get_unless_zero(&obj->refcount))
1096 drm_vma_offset_unlock_lookup(dev->vma_offset_manager);
1101 if (!drm_vma_node_is_allowed(node, priv)) {
1102 drm_gem_object_put_unlocked(obj);
1106 if (node->readonly) {
1107 if (vma->vm_flags & VM_WRITE) {
1108 drm_gem_object_put_unlocked(obj);
1112 vma->vm_flags &= ~VM_MAYWRITE;
1115 ret = drm_gem_mmap_obj(obj, drm_vma_node_size(node) << PAGE_SHIFT,
1118 drm_gem_object_put_unlocked(obj);
1122 EXPORT_SYMBOL(drm_gem_mmap);
1124 void drm_gem_print_info(struct drm_printer *p, unsigned int indent,
1125 const struct drm_gem_object *obj)
1127 drm_printf_indent(p, indent, "name=%d\n", obj->name);
1128 drm_printf_indent(p, indent, "refcount=%u\n",
1129 kref_read(&obj->refcount));
1130 drm_printf_indent(p, indent, "start=%08lx\n",
1131 drm_vma_node_start(&obj->vma_node));
1132 drm_printf_indent(p, indent, "size=%zu\n", obj->size);
1133 drm_printf_indent(p, indent, "imported=%s\n",
1134 obj->import_attach ? "yes" : "no");
1136 if (obj->funcs && obj->funcs->print_info)
1137 obj->funcs->print_info(p, indent, obj);
1138 else if (obj->dev->driver->gem_print_info)
1139 obj->dev->driver->gem_print_info(p, indent, obj);
1143 * drm_gem_pin - Pin backing buffer in memory
1146 * Make sure the backing buffer is pinned in memory.
1149 * 0 on success or a negative error code on failure.
1151 int drm_gem_pin(struct drm_gem_object *obj)
1153 if (obj->funcs && obj->funcs->pin)
1154 return obj->funcs->pin(obj);
1155 else if (obj->dev->driver->gem_prime_pin)
1156 return obj->dev->driver->gem_prime_pin(obj);
1160 EXPORT_SYMBOL(drm_gem_pin);
1163 * drm_gem_unpin - Unpin backing buffer from memory
1166 * Relax the requirement that the backing buffer is pinned in memory.
1168 void drm_gem_unpin(struct drm_gem_object *obj)
1170 if (obj->funcs && obj->funcs->unpin)
1171 obj->funcs->unpin(obj);
1172 else if (obj->dev->driver->gem_prime_unpin)
1173 obj->dev->driver->gem_prime_unpin(obj);
1175 EXPORT_SYMBOL(drm_gem_unpin);
1178 * drm_gem_vmap - Map buffer into kernel virtual address space
1182 * A virtual pointer to a newly created GEM object or an ERR_PTR-encoded negative
1183 * error code on failure.
1185 void *drm_gem_vmap(struct drm_gem_object *obj)
1189 if (obj->funcs && obj->funcs->vmap)
1190 vaddr = obj->funcs->vmap(obj);
1191 else if (obj->dev->driver->gem_prime_vmap)
1192 vaddr = obj->dev->driver->gem_prime_vmap(obj);
1194 vaddr = ERR_PTR(-EOPNOTSUPP);
1197 vaddr = ERR_PTR(-ENOMEM);
1201 EXPORT_SYMBOL(drm_gem_vmap);
1204 * drm_gem_vunmap - Remove buffer mapping from kernel virtual address space
1206 * @vaddr: Virtual address (can be NULL)
1208 void drm_gem_vunmap(struct drm_gem_object *obj, void *vaddr)
1213 if (obj->funcs && obj->funcs->vunmap)
1214 obj->funcs->vunmap(obj, vaddr);
1215 else if (obj->dev->driver->gem_prime_vunmap)
1216 obj->dev->driver->gem_prime_vunmap(obj, vaddr);
1218 EXPORT_SYMBOL(drm_gem_vunmap);
1221 * drm_gem_lock_reservations - Sets up the ww context and acquires
1222 * the lock on an array of GEM objects.
1224 * Once you've locked your reservations, you'll want to set up space
1225 * for your shared fences (if applicable), submit your job, then
1226 * drm_gem_unlock_reservations().
1228 * @objs: drm_gem_objects to lock
1229 * @count: Number of objects in @objs
1230 * @acquire_ctx: struct ww_acquire_ctx that will be initialized as
1231 * part of tracking this set of locked reservations.
1234 drm_gem_lock_reservations(struct drm_gem_object **objs, int count,
1235 struct ww_acquire_ctx *acquire_ctx)
1240 ww_acquire_init(acquire_ctx, &reservation_ww_class);
1243 if (contended != -1) {
1244 struct drm_gem_object *obj = objs[contended];
1246 ret = ww_mutex_lock_slow_interruptible(&obj->resv->lock,
1249 ww_acquire_done(acquire_ctx);
1254 for (i = 0; i < count; i++) {
1258 ret = ww_mutex_lock_interruptible(&objs[i]->resv->lock,
1263 for (j = 0; j < i; j++)
1264 ww_mutex_unlock(&objs[j]->resv->lock);
1266 if (contended != -1 && contended >= i)
1267 ww_mutex_unlock(&objs[contended]->resv->lock);
1269 if (ret == -EDEADLK) {
1274 ww_acquire_done(acquire_ctx);
1279 ww_acquire_done(acquire_ctx);
1283 EXPORT_SYMBOL(drm_gem_lock_reservations);
1286 drm_gem_unlock_reservations(struct drm_gem_object **objs, int count,
1287 struct ww_acquire_ctx *acquire_ctx)
1291 for (i = 0; i < count; i++)
1292 ww_mutex_unlock(&objs[i]->resv->lock);
1294 ww_acquire_fini(acquire_ctx);
1296 EXPORT_SYMBOL(drm_gem_unlock_reservations);