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1/*2 * Copyright © 2008 Intel Corporation3 *4 * Permission is hereby granted, free of charge, to any person obtaining a5 * copy of this software and associated documentation files (the "Software"),6 * to deal in the Software without restriction, including without limitation7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,8 * and/or sell copies of the Software, and to permit persons to whom the9 * Software is furnished to do so, subject to the following conditions:10 *11 * The above copyright notice and this permission notice (including the next12 * paragraph) shall be included in all copies or substantial portions of the13 * Software.14 *15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS21 * IN THE SOFTWARE.22 *23 * Authors:24 *    Eric Anholt <eric@anholt.net>25 *26 */27 28#include <linux/dma-buf.h>29#include <linux/file.h>30#include <linux/fs.h>31#include <linux/iosys-map.h>32#include <linux/mem_encrypt.h>33#include <linux/mm.h>34#include <linux/mman.h>35#include <linux/module.h>36#include <linux/pagemap.h>37#include <linux/pagevec.h>38#include <linux/shmem_fs.h>39#include <linux/slab.h>40#include <linux/string_helpers.h>41#include <linux/types.h>42#include <linux/uaccess.h>43 44#include <drm/drm.h>45#include <drm/drm_device.h>46#include <drm/drm_drv.h>47#include <drm/drm_file.h>48#include <drm/drm_gem.h>49#include <drm/drm_managed.h>50#include <drm/drm_print.h>51#include <drm/drm_vma_manager.h>52 53#include "drm_internal.h"54 55/** @file drm_gem.c56 *57 * This file provides some of the base ioctls and library routines for58 * the graphics memory manager implemented by each device driver.59 *60 * Because various devices have different requirements in terms of61 * synchronization and migration strategies, implementing that is left up to62 * the driver, and all that the general API provides should be generic --63 * allocating objects, reading/writing data with the cpu, freeing objects.64 * Even there, platform-dependent optimizations for reading/writing data with65 * the CPU mean we'll likely hook those out to driver-specific calls.  However,66 * the DRI2 implementation wants to have at least allocate/mmap be generic.67 *68 * The goal was to have swap-backed object allocation managed through69 * struct file.  However, file descriptors as handles to a struct file have70 * two major failings:71 * - Process limits prevent more than 1024 or so being used at a time by72 *   default.73 * - Inability to allocate high fds will aggravate the X Server's select()74 *   handling, and likely that of many GL client applications as well.75 *76 * This led to a plan of using our own integer IDs (called handles, following77 * DRM terminology) to mimic fds, and implement the fd syscalls we need as78 * ioctls.  The objects themselves will still include the struct file so79 * that we can transition to fds if the required kernel infrastructure shows80 * up at a later date, and as our interface with shmfs for memory allocation.81 */82 83static void84drm_gem_init_release(struct drm_device *dev, void *ptr)85{86	drm_vma_offset_manager_destroy(dev->vma_offset_manager);87}88 89/**90 * drm_gem_init - Initialize the GEM device fields91 * @dev: drm_devic structure to initialize92 */93int94drm_gem_init(struct drm_device *dev)95{96	struct drm_vma_offset_manager *vma_offset_manager;97 98	mutex_init(&dev->object_name_lock);99	idr_init_base(&dev->object_name_idr, 1);100 101	vma_offset_manager = drmm_kzalloc(dev, sizeof(*vma_offset_manager),102					  GFP_KERNEL);103	if (!vma_offset_manager) {104		DRM_ERROR("out of memory\n");105		return -ENOMEM;106	}107 108	dev->vma_offset_manager = vma_offset_manager;109	drm_vma_offset_manager_init(vma_offset_manager,110				    DRM_FILE_PAGE_OFFSET_START,111				    DRM_FILE_PAGE_OFFSET_SIZE);112 113	return drmm_add_action(dev, drm_gem_init_release, NULL);114}115 116/**117 * drm_gem_object_init - initialize an allocated shmem-backed GEM object118 * @dev: drm_device the object should be initialized for119 * @obj: drm_gem_object to initialize120 * @size: object size121 *122 * Initialize an already allocated GEM object of the specified size with123 * shmfs backing store.124 */125int drm_gem_object_init(struct drm_device *dev,126			struct drm_gem_object *obj, size_t size)127{128	struct file *filp;129 130	drm_gem_private_object_init(dev, obj, size);131 132	filp = shmem_file_setup("drm mm object", size, VM_NORESERVE);133	if (IS_ERR(filp))134		return PTR_ERR(filp);135 136	obj->filp = filp;137 138	return 0;139}140EXPORT_SYMBOL(drm_gem_object_init);141 142/**143 * drm_gem_private_object_init - initialize an allocated private GEM object144 * @dev: drm_device the object should be initialized for145 * @obj: drm_gem_object to initialize146 * @size: object size147 *148 * Initialize an already allocated GEM object of the specified size with149 * no GEM provided backing store. Instead the caller is responsible for150 * backing the object and handling it.151 */152void drm_gem_private_object_init(struct drm_device *dev,153				 struct drm_gem_object *obj, size_t size)154{155	BUG_ON((size & (PAGE_SIZE - 1)) != 0);156 157	obj->dev = dev;158	obj->filp = NULL;159 160	kref_init(&obj->refcount);161	obj->handle_count = 0;162	obj->size = size;163	dma_resv_init(&obj->_resv);164	if (!obj->resv)165		obj->resv = &obj->_resv;166 167	if (drm_core_check_feature(dev, DRIVER_GEM_GPUVA))168		drm_gem_gpuva_init(obj);169 170	drm_vma_node_reset(&obj->vma_node);171	INIT_LIST_HEAD(&obj->lru_node);172}173EXPORT_SYMBOL(drm_gem_private_object_init);174 175/**176 * drm_gem_private_object_fini - Finalize a failed drm_gem_object177 * @obj: drm_gem_object178 *179 * Uninitialize an already allocated GEM object when it initialized failed180 */181void drm_gem_private_object_fini(struct drm_gem_object *obj)182{183	WARN_ON(obj->dma_buf);184 185	dma_resv_fini(&obj->_resv);186}187EXPORT_SYMBOL(drm_gem_private_object_fini);188 189/**190 * drm_gem_object_handle_free - release resources bound to userspace handles191 * @obj: GEM object to clean up.192 *193 * Called after the last handle to the object has been closed194 *195 * Removes any name for the object. Note that this must be196 * called before drm_gem_object_free or we'll be touching197 * freed memory198 */199static void drm_gem_object_handle_free(struct drm_gem_object *obj)200{201	struct drm_device *dev = obj->dev;202 203	/* Remove any name for this object */204	if (obj->name) {205		idr_remove(&dev->object_name_idr, obj->name);206		obj->name = 0;207	}208}209 210static void drm_gem_object_exported_dma_buf_free(struct drm_gem_object *obj)211{212	/* Unbreak the reference cycle if we have an exported dma_buf. */213	if (obj->dma_buf) {214		dma_buf_put(obj->dma_buf);215		obj->dma_buf = NULL;216	}217}218 219static void220drm_gem_object_handle_put_unlocked(struct drm_gem_object *obj)221{222	struct drm_device *dev = obj->dev;223	bool final = false;224 225	if (WARN_ON(READ_ONCE(obj->handle_count) == 0))226		return;227 228	/*229	* Must bump handle count first as this may be the last230	* ref, in which case the object would disappear before we231	* checked for a name232	*/233 234	mutex_lock(&dev->object_name_lock);235	if (--obj->handle_count == 0) {236		drm_gem_object_handle_free(obj);237		drm_gem_object_exported_dma_buf_free(obj);238		final = true;239	}240	mutex_unlock(&dev->object_name_lock);241 242	if (final)243		drm_gem_object_put(obj);244}245 246/*247 * Called at device or object close to release the file's248 * handle references on objects.249 */250static int251drm_gem_object_release_handle(int id, void *ptr, void *data)252{253	struct drm_file *file_priv = data;254	struct drm_gem_object *obj = ptr;255 256	if (obj->funcs->close)257		obj->funcs->close(obj, file_priv);258 259	drm_prime_remove_buf_handle(&file_priv->prime, id);260	drm_vma_node_revoke(&obj->vma_node, file_priv);261 262	drm_gem_object_handle_put_unlocked(obj);263 264	return 0;265}266 267/**268 * drm_gem_handle_delete - deletes the given file-private handle269 * @filp: drm file-private structure to use for the handle look up270 * @handle: userspace handle to delete271 *272 * Removes the GEM handle from the @filp lookup table which has been added with273 * drm_gem_handle_create(). If this is the last handle also cleans up linked274 * resources like GEM names.275 */276int277drm_gem_handle_delete(struct drm_file *filp, u32 handle)278{279	struct drm_gem_object *obj;280 281	spin_lock(&filp->table_lock);282 283	/* Check if we currently have a reference on the object */284	obj = idr_replace(&filp->object_idr, NULL, handle);285	spin_unlock(&filp->table_lock);286	if (IS_ERR_OR_NULL(obj))287		return -EINVAL;288 289	/* Release driver's reference and decrement refcount. */290	drm_gem_object_release_handle(handle, obj, filp);291 292	/* And finally make the handle available for future allocations. */293	spin_lock(&filp->table_lock);294	idr_remove(&filp->object_idr, handle);295	spin_unlock(&filp->table_lock);296 297	return 0;298}299EXPORT_SYMBOL(drm_gem_handle_delete);300 301/**302 * drm_gem_dumb_map_offset - return the fake mmap offset for a gem object303 * @file: drm file-private structure containing the gem object304 * @dev: corresponding drm_device305 * @handle: gem object handle306 * @offset: return location for the fake mmap offset307 *308 * This implements the &drm_driver.dumb_map_offset kms driver callback for309 * drivers which use gem to manage their backing storage.310 *311 * Returns:312 * 0 on success or a negative error code on failure.313 */314int drm_gem_dumb_map_offset(struct drm_file *file, struct drm_device *dev,315			    u32 handle, u64 *offset)316{317	struct drm_gem_object *obj;318	int ret;319 320	obj = drm_gem_object_lookup(file, handle);321	if (!obj)322		return -ENOENT;323 324	/* Don't allow imported objects to be mapped */325	if (obj->import_attach) {326		ret = -EINVAL;327		goto out;328	}329 330	ret = drm_gem_create_mmap_offset(obj);331	if (ret)332		goto out;333 334	*offset = drm_vma_node_offset_addr(&obj->vma_node);335out:336	drm_gem_object_put(obj);337 338	return ret;339}340EXPORT_SYMBOL_GPL(drm_gem_dumb_map_offset);341 342/**343 * drm_gem_handle_create_tail - internal functions to create a handle344 * @file_priv: drm file-private structure to register the handle for345 * @obj: object to register346 * @handlep: pointer to return the created handle to the caller347 *348 * This expects the &drm_device.object_name_lock to be held already and will349 * drop it before returning. Used to avoid races in establishing new handles350 * when importing an object from either an flink name or a dma-buf.351 *352 * Handles must be release again through drm_gem_handle_delete(). This is done353 * when userspace closes @file_priv for all attached handles, or through the354 * GEM_CLOSE ioctl for individual handles.355 */356int357drm_gem_handle_create_tail(struct drm_file *file_priv,358			   struct drm_gem_object *obj,359			   u32 *handlep)360{361	struct drm_device *dev = obj->dev;362	u32 handle;363	int ret;364 365	WARN_ON(!mutex_is_locked(&dev->object_name_lock));366	if (obj->handle_count++ == 0)367		drm_gem_object_get(obj);368 369	/*370	 * Get the user-visible handle using idr.  Preload and perform371	 * allocation under our spinlock.372	 */373	idr_preload(GFP_KERNEL);374	spin_lock(&file_priv->table_lock);375 376	ret = idr_alloc(&file_priv->object_idr, obj, 1, 0, GFP_NOWAIT);377 378	spin_unlock(&file_priv->table_lock);379	idr_preload_end();380 381	mutex_unlock(&dev->object_name_lock);382	if (ret < 0)383		goto err_unref;384 385	handle = ret;386 387	ret = drm_vma_node_allow(&obj->vma_node, file_priv);388	if (ret)389		goto err_remove;390 391	if (obj->funcs->open) {392		ret = obj->funcs->open(obj, file_priv);393		if (ret)394			goto err_revoke;395	}396 397	*handlep = handle;398	return 0;399 400err_revoke:401	drm_vma_node_revoke(&obj->vma_node, file_priv);402err_remove:403	spin_lock(&file_priv->table_lock);404	idr_remove(&file_priv->object_idr, handle);405	spin_unlock(&file_priv->table_lock);406err_unref:407	drm_gem_object_handle_put_unlocked(obj);408	return ret;409}410 411/**412 * drm_gem_handle_create - create a gem handle for an object413 * @file_priv: drm file-private structure to register the handle for414 * @obj: object to register415 * @handlep: pointer to return the created handle to the caller416 *417 * Create a handle for this object. This adds a handle reference to the object,418 * which includes a regular reference count. Callers will likely want to419 * dereference the object afterwards.420 *421 * Since this publishes @obj to userspace it must be fully set up by this point,422 * drivers must call this last in their buffer object creation callbacks.423 */424int drm_gem_handle_create(struct drm_file *file_priv,425			  struct drm_gem_object *obj,426			  u32 *handlep)427{428	mutex_lock(&obj->dev->object_name_lock);429 430	return drm_gem_handle_create_tail(file_priv, obj, handlep);431}432EXPORT_SYMBOL(drm_gem_handle_create);433 434 435/**436 * drm_gem_free_mmap_offset - release a fake mmap offset for an object437 * @obj: obj in question438 *439 * This routine frees fake offsets allocated by drm_gem_create_mmap_offset().440 *441 * Note that drm_gem_object_release() already calls this function, so drivers442 * don't have to take care of releasing the mmap offset themselves when freeing443 * the GEM object.444 */445void446drm_gem_free_mmap_offset(struct drm_gem_object *obj)447{448	struct drm_device *dev = obj->dev;449 450	drm_vma_offset_remove(dev->vma_offset_manager, &obj->vma_node);451}452EXPORT_SYMBOL(drm_gem_free_mmap_offset);453 454/**455 * drm_gem_create_mmap_offset_size - create a fake mmap offset for an object456 * @obj: obj in question457 * @size: the virtual size458 *459 * GEM memory mapping works by handing back to userspace a fake mmap offset460 * it can use in a subsequent mmap(2) call.  The DRM core code then looks461 * up the object based on the offset and sets up the various memory mapping462 * structures.463 *464 * This routine allocates and attaches a fake offset for @obj, in cases where465 * the virtual size differs from the physical size (ie. &drm_gem_object.size).466 * Otherwise just use drm_gem_create_mmap_offset().467 *468 * This function is idempotent and handles an already allocated mmap offset469 * transparently. Drivers do not need to check for this case.470 */471int472drm_gem_create_mmap_offset_size(struct drm_gem_object *obj, size_t size)473{474	struct drm_device *dev = obj->dev;475 476	return drm_vma_offset_add(dev->vma_offset_manager, &obj->vma_node,477				  size / PAGE_SIZE);478}479EXPORT_SYMBOL(drm_gem_create_mmap_offset_size);480 481/**482 * drm_gem_create_mmap_offset - create a fake mmap offset for an object483 * @obj: obj in question484 *485 * GEM memory mapping works by handing back to userspace a fake mmap offset486 * it can use in a subsequent mmap(2) call.  The DRM core code then looks487 * up the object based on the offset and sets up the various memory mapping488 * structures.489 *490 * This routine allocates and attaches a fake offset for @obj.491 *492 * Drivers can call drm_gem_free_mmap_offset() before freeing @obj to release493 * the fake offset again.494 */495int drm_gem_create_mmap_offset(struct drm_gem_object *obj)496{497	return drm_gem_create_mmap_offset_size(obj, obj->size);498}499EXPORT_SYMBOL(drm_gem_create_mmap_offset);500 501/*502 * Move folios to appropriate lru and release the folios, decrementing the503 * ref count of those folios.504 */505static void drm_gem_check_release_batch(struct folio_batch *fbatch)506{507	check_move_unevictable_folios(fbatch);508	__folio_batch_release(fbatch);509	cond_resched();510}511 512/**513 * drm_gem_get_pages - helper to allocate backing pages for a GEM object514 * from shmem515 * @obj: obj in question516 *517 * This reads the page-array of the shmem-backing storage of the given gem518 * object. An array of pages is returned. If a page is not allocated or519 * swapped-out, this will allocate/swap-in the required pages. Note that the520 * whole object is covered by the page-array and pinned in memory.521 *522 * Use drm_gem_put_pages() to release the array and unpin all pages.523 *524 * This uses the GFP-mask set on the shmem-mapping (see mapping_set_gfp_mask()).525 * If you require other GFP-masks, you have to do those allocations yourself.526 *527 * Note that you are not allowed to change gfp-zones during runtime. That is,528 * shmem_read_mapping_page_gfp() must be called with the same gfp_zone(gfp) as529 * set during initialization. If you have special zone constraints, set them530 * after drm_gem_object_init() via mapping_set_gfp_mask(). shmem-core takes care531 * to keep pages in the required zone during swap-in.532 *533 * This function is only valid on objects initialized with534 * drm_gem_object_init(), but not for those initialized with535 * drm_gem_private_object_init() only.536 */537struct page **drm_gem_get_pages(struct drm_gem_object *obj)538{539	struct address_space *mapping;540	struct page **pages;541	struct folio *folio;542	struct folio_batch fbatch;543	long i, j, npages;544 545	if (WARN_ON(!obj->filp))546		return ERR_PTR(-EINVAL);547 548	/* This is the shared memory object that backs the GEM resource */549	mapping = obj->filp->f_mapping;550 551	/* We already BUG_ON() for non-page-aligned sizes in552	 * drm_gem_object_init(), so we should never hit this unless553	 * driver author is doing something really wrong:554	 */555	WARN_ON((obj->size & (PAGE_SIZE - 1)) != 0);556 557	npages = obj->size >> PAGE_SHIFT;558 559	pages = kvmalloc_array(npages, sizeof(struct page *), GFP_KERNEL);560	if (pages == NULL)561		return ERR_PTR(-ENOMEM);562 563	mapping_set_unevictable(mapping);564 565	i = 0;566	while (i < npages) {567		long nr;568		folio = shmem_read_folio_gfp(mapping, i,569				mapping_gfp_mask(mapping));570		if (IS_ERR(folio))571			goto fail;572		nr = min(npages - i, folio_nr_pages(folio));573		for (j = 0; j < nr; j++, i++)574			pages[i] = folio_file_page(folio, i);575 576		/* Make sure shmem keeps __GFP_DMA32 allocated pages in the577		 * correct region during swapin. Note that this requires578		 * __GFP_DMA32 to be set in mapping_gfp_mask(inode->i_mapping)579		 * so shmem can relocate pages during swapin if required.580		 */581		BUG_ON(mapping_gfp_constraint(mapping, __GFP_DMA32) &&582				(folio_pfn(folio) >= 0x00100000UL));583	}584 585	return pages;586 587fail:588	mapping_clear_unevictable(mapping);589	folio_batch_init(&fbatch);590	j = 0;591	while (j < i) {592		struct folio *f = page_folio(pages[j]);593		if (!folio_batch_add(&fbatch, f))594			drm_gem_check_release_batch(&fbatch);595		j += folio_nr_pages(f);596	}597	if (fbatch.nr)598		drm_gem_check_release_batch(&fbatch);599 600	kvfree(pages);601	return ERR_CAST(folio);602}603EXPORT_SYMBOL(drm_gem_get_pages);604 605/**606 * drm_gem_put_pages - helper to free backing pages for a GEM object607 * @obj: obj in question608 * @pages: pages to free609 * @dirty: if true, pages will be marked as dirty610 * @accessed: if true, the pages will be marked as accessed611 */612void drm_gem_put_pages(struct drm_gem_object *obj, struct page **pages,613		bool dirty, bool accessed)614{615	int i, npages;616	struct address_space *mapping;617	struct folio_batch fbatch;618 619	mapping = file_inode(obj->filp)->i_mapping;620	mapping_clear_unevictable(mapping);621 622	/* We already BUG_ON() for non-page-aligned sizes in623	 * drm_gem_object_init(), so we should never hit this unless624	 * driver author is doing something really wrong:625	 */626	WARN_ON((obj->size & (PAGE_SIZE - 1)) != 0);627 628	npages = obj->size >> PAGE_SHIFT;629 630	folio_batch_init(&fbatch);631	for (i = 0; i < npages; i++) {632		struct folio *folio;633 634		if (!pages[i])635			continue;636		folio = page_folio(pages[i]);637 638		if (dirty)639			folio_mark_dirty(folio);640 641		if (accessed)642			folio_mark_accessed(folio);643 644		/* Undo the reference we took when populating the table */645		if (!folio_batch_add(&fbatch, folio))646			drm_gem_check_release_batch(&fbatch);647		i += folio_nr_pages(folio) - 1;648	}649	if (folio_batch_count(&fbatch))650		drm_gem_check_release_batch(&fbatch);651 652	kvfree(pages);653}654EXPORT_SYMBOL(drm_gem_put_pages);655 656static int objects_lookup(struct drm_file *filp, u32 *handle, int count,657			  struct drm_gem_object **objs)658{659	int i, ret = 0;660	struct drm_gem_object *obj;661 662	spin_lock(&filp->table_lock);663 664	for (i = 0; i < count; i++) {665		/* Check if we currently have a reference on the object */666		obj = idr_find(&filp->object_idr, handle[i]);667		if (!obj) {668			ret = -ENOENT;669			break;670		}671		drm_gem_object_get(obj);672		objs[i] = obj;673	}674	spin_unlock(&filp->table_lock);675 676	return ret;677}678 679/**680 * drm_gem_objects_lookup - look up GEM objects from an array of handles681 * @filp: DRM file private date682 * @bo_handles: user pointer to array of userspace handle683 * @count: size of handle array684 * @objs_out: returned pointer to array of drm_gem_object pointers685 *686 * Takes an array of userspace handles and returns a newly allocated array of687 * GEM objects.688 *689 * For a single handle lookup, use drm_gem_object_lookup().690 *691 * Returns:692 * @objs filled in with GEM object pointers. Returned GEM objects need to be693 * released with drm_gem_object_put(). -ENOENT is returned on a lookup694 * failure. 0 is returned on success.695 *696 */697int drm_gem_objects_lookup(struct drm_file *filp, void __user *bo_handles,698			   int count, struct drm_gem_object ***objs_out)699{700	int ret;701	u32 *handles;702	struct drm_gem_object **objs;703 704	if (!count)705		return 0;706 707	objs = kvmalloc_array(count, sizeof(struct drm_gem_object *),708			     GFP_KERNEL | __GFP_ZERO);709	if (!objs)710		return -ENOMEM;711 712	*objs_out = objs;713 714	handles = kvmalloc_array(count, sizeof(u32), GFP_KERNEL);715	if (!handles) {716		ret = -ENOMEM;717		goto out;718	}719 720	if (copy_from_user(handles, bo_handles, count * sizeof(u32))) {721		ret = -EFAULT;722		DRM_DEBUG("Failed to copy in GEM handles\n");723		goto out;724	}725 726	ret = objects_lookup(filp, handles, count, objs);727out:728	kvfree(handles);729	return ret;730 731}732EXPORT_SYMBOL(drm_gem_objects_lookup);733 734/**735 * drm_gem_object_lookup - look up a GEM object from its handle736 * @filp: DRM file private date737 * @handle: userspace handle738 *739 * If looking up an array of handles, use drm_gem_objects_lookup().740 *741 * Returns:742 * A reference to the object named by the handle if such exists on @filp, NULL743 * otherwise.744 */745struct drm_gem_object *746drm_gem_object_lookup(struct drm_file *filp, u32 handle)747{748	struct drm_gem_object *obj = NULL;749 750	objects_lookup(filp, &handle, 1, &obj);751	return obj;752}753EXPORT_SYMBOL(drm_gem_object_lookup);754 755/**756 * drm_gem_dma_resv_wait - Wait on GEM object's reservation's objects757 * shared and/or exclusive fences.758 * @filep: DRM file private date759 * @handle: userspace handle760 * @wait_all: if true, wait on all fences, else wait on just exclusive fence761 * @timeout: timeout value in jiffies or zero to return immediately762 *763 * Returns:764 * Returns -ERESTARTSYS if interrupted, 0 if the wait timed out, or765 * greater than 0 on success.766 */767long drm_gem_dma_resv_wait(struct drm_file *filep, u32 handle,768				    bool wait_all, unsigned long timeout)769{770	long ret;771	struct drm_gem_object *obj;772 773	obj = drm_gem_object_lookup(filep, handle);774	if (!obj) {775		DRM_DEBUG("Failed to look up GEM BO %d\n", handle);776		return -EINVAL;777	}778 779	ret = dma_resv_wait_timeout(obj->resv, dma_resv_usage_rw(wait_all),780				    true, timeout);781	if (ret == 0)782		ret = -ETIME;783	else if (ret > 0)784		ret = 0;785 786	drm_gem_object_put(obj);787 788	return ret;789}790EXPORT_SYMBOL(drm_gem_dma_resv_wait);791 792/**793 * drm_gem_close_ioctl - implementation of the GEM_CLOSE ioctl794 * @dev: drm_device795 * @data: ioctl data796 * @file_priv: drm file-private structure797 *798 * Releases the handle to an mm object.799 */800int801drm_gem_close_ioctl(struct drm_device *dev, void *data,802		    struct drm_file *file_priv)803{804	struct drm_gem_close *args = data;805	int ret;806 807	if (!drm_core_check_feature(dev, DRIVER_GEM))808		return -EOPNOTSUPP;809 810	ret = drm_gem_handle_delete(file_priv, args->handle);811 812	return ret;813}814 815/**816 * drm_gem_flink_ioctl - implementation of the GEM_FLINK ioctl817 * @dev: drm_device818 * @data: ioctl data819 * @file_priv: drm file-private structure820 *821 * Create a global name for an object, returning the name.822 *823 * Note that the name does not hold a reference; when the object824 * is freed, the name goes away.825 */826int827drm_gem_flink_ioctl(struct drm_device *dev, void *data,828		    struct drm_file *file_priv)829{830	struct drm_gem_flink *args = data;831	struct drm_gem_object *obj;832	int ret;833 834	if (!drm_core_check_feature(dev, DRIVER_GEM))835		return -EOPNOTSUPP;836 837	obj = drm_gem_object_lookup(file_priv, args->handle);838	if (obj == NULL)839		return -ENOENT;840 841	mutex_lock(&dev->object_name_lock);842	/* prevent races with concurrent gem_close. */843	if (obj->handle_count == 0) {844		ret = -ENOENT;845		goto err;846	}847 848	if (!obj->name) {849		ret = idr_alloc(&dev->object_name_idr, obj, 1, 0, GFP_KERNEL);850		if (ret < 0)851			goto err;852 853		obj->name = ret;854	}855 856	args->name = (uint64_t) obj->name;857	ret = 0;858 859err:860	mutex_unlock(&dev->object_name_lock);861	drm_gem_object_put(obj);862	return ret;863}864 865/**866 * drm_gem_open_ioctl - implementation of the GEM_OPEN ioctl867 * @dev: drm_device868 * @data: ioctl data869 * @file_priv: drm file-private structure870 *871 * Open an object using the global name, returning a handle and the size.872 *873 * This handle (of course) holds a reference to the object, so the object874 * will not go away until the handle is deleted.875 */876int877drm_gem_open_ioctl(struct drm_device *dev, void *data,878		   struct drm_file *file_priv)879{880	struct drm_gem_open *args = data;881	struct drm_gem_object *obj;882	int ret;883	u32 handle;884 885	if (!drm_core_check_feature(dev, DRIVER_GEM))886		return -EOPNOTSUPP;887 888	mutex_lock(&dev->object_name_lock);889	obj = idr_find(&dev->object_name_idr, (int) args->name);890	if (obj) {891		drm_gem_object_get(obj);892	} else {893		mutex_unlock(&dev->object_name_lock);894		return -ENOENT;895	}896 897	/* drm_gem_handle_create_tail unlocks dev->object_name_lock. */898	ret = drm_gem_handle_create_tail(file_priv, obj, &handle);899	if (ret)900		goto err;901 902	args->handle = handle;903	args->size = obj->size;904 905err:906	drm_gem_object_put(obj);907	return ret;908}909 910/**911 * drm_gem_open - initializes GEM file-private structures at devnode open time912 * @dev: drm_device which is being opened by userspace913 * @file_private: drm file-private structure to set up914 *915 * Called at device open time, sets up the structure for handling refcounting916 * of mm objects.917 */918void919drm_gem_open(struct drm_device *dev, struct drm_file *file_private)920{921	idr_init_base(&file_private->object_idr, 1);922	spin_lock_init(&file_private->table_lock);923}924 925/**926 * drm_gem_release - release file-private GEM resources927 * @dev: drm_device which is being closed by userspace928 * @file_private: drm file-private structure to clean up929 *930 * Called at close time when the filp is going away.931 *932 * Releases any remaining references on objects by this filp.933 */934void935drm_gem_release(struct drm_device *dev, struct drm_file *file_private)936{937	idr_for_each(&file_private->object_idr,938		     &drm_gem_object_release_handle, file_private);939	idr_destroy(&file_private->object_idr);940}941 942/**943 * drm_gem_object_release - release GEM buffer object resources944 * @obj: GEM buffer object945 *946 * This releases any structures and resources used by @obj and is the inverse of947 * drm_gem_object_init().948 */949void950drm_gem_object_release(struct drm_gem_object *obj)951{952	if (obj->filp)953		fput(obj->filp);954 955	drm_gem_private_object_fini(obj);956 957	drm_gem_free_mmap_offset(obj);958	drm_gem_lru_remove(obj);959}960EXPORT_SYMBOL(drm_gem_object_release);961 962/**963 * drm_gem_object_free - free a GEM object964 * @kref: kref of the object to free965 *966 * Called after the last reference to the object has been lost.967 *968 * Frees the object969 */970void971drm_gem_object_free(struct kref *kref)972{973	struct drm_gem_object *obj =974		container_of(kref, struct drm_gem_object, refcount);975 976	if (WARN_ON(!obj->funcs->free))977		return;978 979	obj->funcs->free(obj);980}981EXPORT_SYMBOL(drm_gem_object_free);982 983/**984 * drm_gem_vm_open - vma->ops->open implementation for GEM985 * @vma: VM area structure986 *987 * This function implements the #vm_operations_struct open() callback for GEM988 * drivers. This must be used together with drm_gem_vm_close().989 */990void drm_gem_vm_open(struct vm_area_struct *vma)991{992	struct drm_gem_object *obj = vma->vm_private_data;993 994	drm_gem_object_get(obj);995}996EXPORT_SYMBOL(drm_gem_vm_open);997 998/**999 * drm_gem_vm_close - vma->ops->close implementation for GEM1000 * @vma: VM area structure1001 *1002 * This function implements the #vm_operations_struct close() callback for GEM1003 * drivers. This must be used together with drm_gem_vm_open().1004 */1005void drm_gem_vm_close(struct vm_area_struct *vma)1006{1007	struct drm_gem_object *obj = vma->vm_private_data;1008 1009	drm_gem_object_put(obj);1010}1011EXPORT_SYMBOL(drm_gem_vm_close);1012 1013/**1014 * drm_gem_mmap_obj - memory map a GEM object1015 * @obj: the GEM object to map1016 * @obj_size: the object size to be mapped, in bytes1017 * @vma: VMA for the area to be mapped1018 *1019 * Set up the VMA to prepare mapping of the GEM object using the GEM object's1020 * vm_ops. Depending on their requirements, GEM objects can either1021 * provide a fault handler in their vm_ops (in which case any accesses to1022 * the object will be trapped, to perform migration, GTT binding, surface1023 * register allocation, or performance monitoring), or mmap the buffer memory1024 * synchronously after calling drm_gem_mmap_obj.1025 *1026 * This function is mainly intended to implement the DMABUF mmap operation, when1027 * the GEM object is not looked up based on its fake offset. To implement the1028 * DRM mmap operation, drivers should use the drm_gem_mmap() function.1029 *1030 * drm_gem_mmap_obj() assumes the user is granted access to the buffer while1031 * drm_gem_mmap() prevents unprivileged users from mapping random objects. So1032 * callers must verify access restrictions before calling this helper.1033 *1034 * Return 0 or success or -EINVAL if the object size is smaller than the VMA1035 * size, or if no vm_ops are provided.1036 */1037int drm_gem_mmap_obj(struct drm_gem_object *obj, unsigned long obj_size,1038		     struct vm_area_struct *vma)1039{1040	int ret;1041 1042	/* Check for valid size. */1043	if (obj_size < vma->vm_end - vma->vm_start)1044		return -EINVAL;1045 1046	/* Take a ref for this mapping of the object, so that the fault1047	 * handler can dereference the mmap offset's pointer to the object.1048	 * This reference is cleaned up by the corresponding vm_close1049	 * (which should happen whether the vma was created by this call, or1050	 * by a vm_open due to mremap or partial unmap or whatever).1051	 */1052	drm_gem_object_get(obj);1053 1054	vma->vm_private_data = obj;1055	vma->vm_ops = obj->funcs->vm_ops;1056 1057	if (obj->funcs->mmap) {1058		ret = obj->funcs->mmap(obj, vma);1059		if (ret)1060			goto err_drm_gem_object_put;1061		WARN_ON(!(vma->vm_flags & VM_DONTEXPAND));1062	} else {1063		if (!vma->vm_ops) {1064			ret = -EINVAL;1065			goto err_drm_gem_object_put;1066		}1067 1068		vm_flags_set(vma, VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP);1069		vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags));1070		vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);1071	}1072 1073	return 0;1074 1075err_drm_gem_object_put:1076	drm_gem_object_put(obj);1077	return ret;1078}1079EXPORT_SYMBOL(drm_gem_mmap_obj);1080 1081/**1082 * drm_gem_mmap - memory map routine for GEM objects1083 * @filp: DRM file pointer1084 * @vma: VMA for the area to be mapped1085 *1086 * If a driver supports GEM object mapping, mmap calls on the DRM file1087 * descriptor will end up here.1088 *1089 * Look up the GEM object based on the offset passed in (vma->vm_pgoff will1090 * contain the fake offset we created when the GTT map ioctl was called on1091 * the object) and map it with a call to drm_gem_mmap_obj().1092 *1093 * If the caller is not granted access to the buffer object, the mmap will fail1094 * with EACCES. Please see the vma manager for more information.1095 */1096int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma)1097{1098	struct drm_file *priv = filp->private_data;1099	struct drm_device *dev = priv->minor->dev;1100	struct drm_gem_object *obj = NULL;1101	struct drm_vma_offset_node *node;1102	int ret;1103 1104	if (drm_dev_is_unplugged(dev))1105		return -ENODEV;1106 1107	drm_vma_offset_lock_lookup(dev->vma_offset_manager);1108	node = drm_vma_offset_exact_lookup_locked(dev->vma_offset_manager,1109						  vma->vm_pgoff,1110						  vma_pages(vma));1111	if (likely(node)) {1112		obj = container_of(node, struct drm_gem_object, vma_node);1113		/*1114		 * When the object is being freed, after it hits 0-refcnt it1115		 * proceeds to tear down the object. In the process it will1116		 * attempt to remove the VMA offset and so acquire this1117		 * mgr->vm_lock.  Therefore if we find an object with a 0-refcnt1118		 * that matches our range, we know it is in the process of being1119		 * destroyed and will be freed as soon as we release the lock -1120		 * so we have to check for the 0-refcnted object and treat it as1121		 * invalid.1122		 */1123		if (!kref_get_unless_zero(&obj->refcount))1124			obj = NULL;1125	}1126	drm_vma_offset_unlock_lookup(dev->vma_offset_manager);1127 1128	if (!obj)1129		return -EINVAL;1130 1131	if (!drm_vma_node_is_allowed(node, priv)) {1132		drm_gem_object_put(obj);1133		return -EACCES;1134	}1135 1136	ret = drm_gem_mmap_obj(obj, drm_vma_node_size(node) << PAGE_SHIFT,1137			       vma);1138 1139	drm_gem_object_put(obj);1140 1141	return ret;1142}1143EXPORT_SYMBOL(drm_gem_mmap);1144 1145void drm_gem_print_info(struct drm_printer *p, unsigned int indent,1146			const struct drm_gem_object *obj)1147{1148	drm_printf_indent(p, indent, "name=%d\n", obj->name);1149	drm_printf_indent(p, indent, "refcount=%u\n",1150			  kref_read(&obj->refcount));1151	drm_printf_indent(p, indent, "start=%08lx\n",1152			  drm_vma_node_start(&obj->vma_node));1153	drm_printf_indent(p, indent, "size=%zu\n", obj->size);1154	drm_printf_indent(p, indent, "imported=%s\n",1155			  str_yes_no(obj->import_attach));1156 1157	if (obj->funcs->print_info)1158		obj->funcs->print_info(p, indent, obj);1159}1160 1161int drm_gem_pin_locked(struct drm_gem_object *obj)1162{1163	if (obj->funcs->pin)1164		return obj->funcs->pin(obj);1165 1166	return 0;1167}1168 1169void drm_gem_unpin_locked(struct drm_gem_object *obj)1170{1171	if (obj->funcs->unpin)1172		obj->funcs->unpin(obj);1173}1174 1175int drm_gem_pin(struct drm_gem_object *obj)1176{1177	int ret;1178 1179	dma_resv_lock(obj->resv, NULL);1180	ret = drm_gem_pin_locked(obj);1181	dma_resv_unlock(obj->resv);1182 1183	return ret;1184}1185 1186void drm_gem_unpin(struct drm_gem_object *obj)1187{1188	dma_resv_lock(obj->resv, NULL);1189	drm_gem_unpin_locked(obj);1190	dma_resv_unlock(obj->resv);1191}1192 1193int drm_gem_vmap(struct drm_gem_object *obj, struct iosys_map *map)1194{1195	int ret;1196 1197	dma_resv_assert_held(obj->resv);1198 1199	if (!obj->funcs->vmap)1200		return -EOPNOTSUPP;1201 1202	ret = obj->funcs->vmap(obj, map);1203	if (ret)1204		return ret;1205	else if (iosys_map_is_null(map))1206		return -ENOMEM;1207 1208	return 0;1209}1210EXPORT_SYMBOL(drm_gem_vmap);1211 1212void drm_gem_vunmap(struct drm_gem_object *obj, struct iosys_map *map)1213{1214	dma_resv_assert_held(obj->resv);1215 1216	if (iosys_map_is_null(map))1217		return;1218 1219	if (obj->funcs->vunmap)1220		obj->funcs->vunmap(obj, map);1221 1222	/* Always set the mapping to NULL. Callers may rely on this. */1223	iosys_map_clear(map);1224}1225EXPORT_SYMBOL(drm_gem_vunmap);1226 1227void drm_gem_lock(struct drm_gem_object *obj)1228{1229	dma_resv_lock(obj->resv, NULL);1230}1231EXPORT_SYMBOL(drm_gem_lock);1232 1233void drm_gem_unlock(struct drm_gem_object *obj)1234{1235	dma_resv_unlock(obj->resv);1236}1237EXPORT_SYMBOL(drm_gem_unlock);1238 1239int drm_gem_vmap_unlocked(struct drm_gem_object *obj, struct iosys_map *map)1240{1241	int ret;1242 1243	dma_resv_lock(obj->resv, NULL);1244	ret = drm_gem_vmap(obj, map);1245	dma_resv_unlock(obj->resv);1246 1247	return ret;1248}1249EXPORT_SYMBOL(drm_gem_vmap_unlocked);1250 1251void drm_gem_vunmap_unlocked(struct drm_gem_object *obj, struct iosys_map *map)1252{1253	dma_resv_lock(obj->resv, NULL);1254	drm_gem_vunmap(obj, map);1255	dma_resv_unlock(obj->resv);1256}1257EXPORT_SYMBOL(drm_gem_vunmap_unlocked);1258 1259/**1260 * drm_gem_lock_reservations - Sets up the ww context and acquires1261 * the lock on an array of GEM objects.1262 *1263 * Once you've locked your reservations, you'll want to set up space1264 * for your shared fences (if applicable), submit your job, then1265 * drm_gem_unlock_reservations().1266 *1267 * @objs: drm_gem_objects to lock1268 * @count: Number of objects in @objs1269 * @acquire_ctx: struct ww_acquire_ctx that will be initialized as1270 * part of tracking this set of locked reservations.1271 */1272int1273drm_gem_lock_reservations(struct drm_gem_object **objs, int count,1274			  struct ww_acquire_ctx *acquire_ctx)1275{1276	int contended = -1;1277	int i, ret;1278 1279	ww_acquire_init(acquire_ctx, &reservation_ww_class);1280 1281retry:1282	if (contended != -1) {1283		struct drm_gem_object *obj = objs[contended];1284 1285		ret = dma_resv_lock_slow_interruptible(obj->resv,1286								 acquire_ctx);1287		if (ret) {1288			ww_acquire_fini(acquire_ctx);1289			return ret;1290		}1291	}1292 1293	for (i = 0; i < count; i++) {1294		if (i == contended)1295			continue;1296 1297		ret = dma_resv_lock_interruptible(objs[i]->resv,1298							    acquire_ctx);1299		if (ret) {1300			int j;1301 1302			for (j = 0; j < i; j++)1303				dma_resv_unlock(objs[j]->resv);1304 1305			if (contended != -1 && contended >= i)1306				dma_resv_unlock(objs[contended]->resv);1307 1308			if (ret == -EDEADLK) {1309				contended = i;1310				goto retry;1311			}1312 1313			ww_acquire_fini(acquire_ctx);1314			return ret;1315		}1316	}1317 1318	ww_acquire_done(acquire_ctx);1319 1320	return 0;1321}1322EXPORT_SYMBOL(drm_gem_lock_reservations);1323 1324void1325drm_gem_unlock_reservations(struct drm_gem_object **objs, int count,1326			    struct ww_acquire_ctx *acquire_ctx)1327{1328	int i;1329 1330	for (i = 0; i < count; i++)1331		dma_resv_unlock(objs[i]->resv);1332 1333	ww_acquire_fini(acquire_ctx);1334}1335EXPORT_SYMBOL(drm_gem_unlock_reservations);1336 1337/**1338 * drm_gem_lru_init - initialize a LRU1339 *1340 * @lru: The LRU to initialize1341 * @lock: The lock protecting the LRU1342 */1343void1344drm_gem_lru_init(struct drm_gem_lru *lru, struct mutex *lock)1345{1346	lru->lock = lock;1347	lru->count = 0;1348	INIT_LIST_HEAD(&lru->list);1349}1350EXPORT_SYMBOL(drm_gem_lru_init);1351 1352static void1353drm_gem_lru_remove_locked(struct drm_gem_object *obj)1354{1355	obj->lru->count -= obj->size >> PAGE_SHIFT;1356	WARN_ON(obj->lru->count < 0);1357	list_del(&obj->lru_node);1358	obj->lru = NULL;1359}1360 1361/**1362 * drm_gem_lru_remove - remove object from whatever LRU it is in1363 *1364 * If the object is currently in any LRU, remove it.1365 *1366 * @obj: The GEM object to remove from current LRU1367 */1368void1369drm_gem_lru_remove(struct drm_gem_object *obj)1370{1371	struct drm_gem_lru *lru = obj->lru;1372 1373	if (!lru)1374		return;1375 1376	mutex_lock(lru->lock);1377	drm_gem_lru_remove_locked(obj);1378	mutex_unlock(lru->lock);1379}1380EXPORT_SYMBOL(drm_gem_lru_remove);1381 1382/**1383 * drm_gem_lru_move_tail_locked - move the object to the tail of the LRU1384 *1385 * Like &drm_gem_lru_move_tail but lru lock must be held1386 *1387 * @lru: The LRU to move the object into.1388 * @obj: The GEM object to move into this LRU1389 */1390void1391drm_gem_lru_move_tail_locked(struct drm_gem_lru *lru, struct drm_gem_object *obj)1392{1393	lockdep_assert_held_once(lru->lock);1394 1395	if (obj->lru)1396		drm_gem_lru_remove_locked(obj);1397 1398	lru->count += obj->size >> PAGE_SHIFT;1399	list_add_tail(&obj->lru_node, &lru->list);1400	obj->lru = lru;1401}1402EXPORT_SYMBOL(drm_gem_lru_move_tail_locked);1403 1404/**1405 * drm_gem_lru_move_tail - move the object to the tail of the LRU1406 *1407 * If the object is already in this LRU it will be moved to the1408 * tail.  Otherwise it will be removed from whichever other LRU1409 * it is in (if any) and moved into this LRU.1410 *1411 * @lru: The LRU to move the object into.1412 * @obj: The GEM object to move into this LRU1413 */1414void1415drm_gem_lru_move_tail(struct drm_gem_lru *lru, struct drm_gem_object *obj)1416{1417	mutex_lock(lru->lock);1418	drm_gem_lru_move_tail_locked(lru, obj);1419	mutex_unlock(lru->lock);1420}1421EXPORT_SYMBOL(drm_gem_lru_move_tail);1422 1423/**1424 * drm_gem_lru_scan - helper to implement shrinker.scan_objects1425 *1426 * If the shrink callback succeeds, it is expected that the driver1427 * move the object out of this LRU.1428 *1429 * If the LRU possibly contain active buffers, it is the responsibility1430 * of the shrink callback to check for this (ie. dma_resv_test_signaled())1431 * or if necessary block until the buffer becomes idle.1432 *1433 * @lru: The LRU to scan1434 * @nr_to_scan: The number of pages to try to reclaim1435 * @remaining: The number of pages left to reclaim, should be initialized by caller1436 * @shrink: Callback to try to shrink/reclaim the object.1437 */1438unsigned long1439drm_gem_lru_scan(struct drm_gem_lru *lru,1440		 unsigned int nr_to_scan,1441		 unsigned long *remaining,1442		 bool (*shrink)(struct drm_gem_object *obj))1443{1444	struct drm_gem_lru still_in_lru;1445	struct drm_gem_object *obj;1446	unsigned freed = 0;1447 1448	drm_gem_lru_init(&still_in_lru, lru->lock);1449 1450	mutex_lock(lru->lock);1451 1452	while (freed < nr_to_scan) {1453		obj = list_first_entry_or_null(&lru->list, typeof(*obj), lru_node);1454 1455		if (!obj)1456			break;1457 1458		drm_gem_lru_move_tail_locked(&still_in_lru, obj);1459 1460		/*1461		 * If it's in the process of being freed, gem_object->free()1462		 * may be blocked on lock waiting to remove it.  So just1463		 * skip it.1464		 */1465		if (!kref_get_unless_zero(&obj->refcount))1466			continue;1467 1468		/*1469		 * Now that we own a reference, we can drop the lock for the1470		 * rest of the loop body, to reduce contention with other1471		 * code paths that need the LRU lock1472		 */1473		mutex_unlock(lru->lock);1474 1475		/*1476		 * Note that this still needs to be trylock, since we can1477		 * hit shrinker in response to trying to get backing pages1478		 * for this obj (ie. while it's lock is already held)1479		 */1480		if (!dma_resv_trylock(obj->resv)) {1481			*remaining += obj->size >> PAGE_SHIFT;1482			goto tail;1483		}1484 1485		if (shrink(obj)) {1486			freed += obj->size >> PAGE_SHIFT;1487 1488			/*1489			 * If we succeeded in releasing the object's backing1490			 * pages, we expect the driver to have moved the object1491			 * out of this LRU1492			 */1493			WARN_ON(obj->lru == &still_in_lru);1494			WARN_ON(obj->lru == lru);1495		}1496 1497		dma_resv_unlock(obj->resv);1498 1499tail:1500		drm_gem_object_put(obj);1501		mutex_lock(lru->lock);1502	}1503 1504	/*1505	 * Move objects we've skipped over out of the temporary still_in_lru1506	 * back into this LRU1507	 */1508	list_for_each_entry (obj, &still_in_lru.list, lru_node)1509		obj->lru = lru;1510	list_splice_tail(&still_in_lru.list, &lru->list);1511	lru->count += still_in_lru.count;1512 1513	mutex_unlock(lru->lock);1514 1515	return freed;1516}1517EXPORT_SYMBOL(drm_gem_lru_scan);1518 1519/**1520 * drm_gem_evict - helper to evict backing pages for a GEM object1521 * @obj: obj in question1522 */1523int drm_gem_evict(struct drm_gem_object *obj)1524{1525	dma_resv_assert_held(obj->resv);1526 1527	if (!dma_resv_test_signaled(obj->resv, DMA_RESV_USAGE_READ))1528		return -EBUSY;1529 1530	if (obj->funcs->evict)1531		return obj->funcs->evict(obj);1532 1533	return 0;1534}1535EXPORT_SYMBOL(drm_gem_evict);1536