drivers/gpu/drm/panthor/panthor_gem.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0 or MIT
 /* Copyright 2019 Linaro, Ltd, Rob Herring <robh@kernel.org> */
 /* Copyright 2023 Collabora ltd. */

 #include <linux/cleanup.h>
 #include <linux/dma-buf.h>
 #include <linux/dma-mapping.h>
 #include <linux/err.h>
 #include <linux/slab.h>

 #include <drm/drm_print.h>
 #include <drm/panthor_drm.h>

 #include "panthor_device.h"
 #include "panthor_fw.h"
 #include "panthor_gem.h"
 #include "panthor_mmu.h"

 #ifdef CONFIG_DEBUG_FS
 static void panthor_gem_debugfs_bo_init(struct panthor_gem_object *bo)
 {
 	INIT_LIST_HEAD(&bo->debugfs.node);
 }

 static void panthor_gem_debugfs_bo_add(struct panthor_gem_object *bo)
 {
 	struct panthor_device *ptdev = container_of(bo->base.base.dev,
 						    struct panthor_device, base);

 	bo->debugfs.creator.tgid = current->group_leader->pid;
 	get_task_comm(bo->debugfs.creator.process_name, current->group_leader);

 	mutex_lock(&ptdev->gems.lock);
 	list_add_tail(&bo->debugfs.node, &ptdev->gems.node);
 	mutex_unlock(&ptdev->gems.lock);
 }

 static void panthor_gem_debugfs_bo_rm(struct panthor_gem_object *bo)
 {
 	struct panthor_device *ptdev = container_of(bo->base.base.dev,
 						    struct panthor_device, base);

 	if (list_empty(&bo->debugfs.node))
 		return;

 	mutex_lock(&ptdev->gems.lock);
 	list_del_init(&bo->debugfs.node);
 	mutex_unlock(&ptdev->gems.lock);
 }

 static void panthor_gem_debugfs_set_usage_flags(struct panthor_gem_object *bo, u32 usage_flags)
 {
 	bo->debugfs.flags = usage_flags;
 	panthor_gem_debugfs_bo_add(bo);
 }
 #else
 static void panthor_gem_debugfs_bo_rm(struct panthor_gem_object *bo) {}
 static void panthor_gem_debugfs_set_usage_flags(struct panthor_gem_object *bo, u32 usage_flags) {}
 static void panthor_gem_debugfs_bo_init(struct panthor_gem_object *bo) {}
 #endif

 static void panthor_gem_free_object(struct drm_gem_object *obj)
 {
 	struct panthor_gem_object *bo = to_panthor_bo(obj);
 	struct drm_gem_object *vm_root_gem = bo->exclusive_vm_root_gem;

 	panthor_gem_debugfs_bo_rm(bo);

 	/*
 	 * Label might have been allocated with kstrdup_const(),
 	 * we need to take that into account when freeing the memory
 	 */
 	kfree_const(bo->label.str);

 	mutex_destroy(&bo->label.lock);

 	drm_gem_free_mmap_offset(&bo->base.base);
 	drm_gem_shmem_free(&bo->base);
 	drm_gem_object_put(vm_root_gem);
 }

 /**
  * panthor_kernel_bo_destroy() - Destroy a kernel buffer object
  * @bo: Kernel buffer object to destroy. If NULL or an ERR_PTR(), the destruction
  * is skipped.
  */
 void panthor_kernel_bo_destroy(struct panthor_kernel_bo *bo)
 {
 	struct panthor_vm *vm;

 	if (IS_ERR_OR_NULL(bo))
 		return;

 	vm = bo->vm;
 	panthor_kernel_bo_vunmap(bo);

 	drm_WARN_ON(bo->obj->dev,
 		    to_panthor_bo(bo->obj)->exclusive_vm_root_gem != panthor_vm_root_gem(vm));
 	panthor_vm_unmap_range(vm, bo->va_node.start, bo->va_node.size);
 	panthor_vm_free_va(vm, &bo->va_node);
 	drm_gem_object_put(bo->obj);
 	panthor_vm_put(vm);
 	kfree(bo);
 }

 /**
  * panthor_kernel_bo_create() - Create and map a GEM object to a VM
  * @ptdev: Device.
  * @vm: VM to map the GEM to. If NULL, the kernel object is not GPU mapped.
  * @size: Size of the buffer object.
  * @bo_flags: Combination of drm_panthor_bo_flags flags.
  * @vm_map_flags: Combination of drm_panthor_vm_bind_op_flags (only those
  * that are related to map operations).
  * @gpu_va: GPU address assigned when mapping to the VM.
  * If gpu_va == PANTHOR_VM_KERNEL_AUTO_VA, the virtual address will be
  * automatically allocated.
  * @name: Descriptive label of the BO's contents
  *
  * Return: A valid pointer in case of success, an ERR_PTR() otherwise.
  */
 struct panthor_kernel_bo *
 panthor_kernel_bo_create(struct panthor_device *ptdev, struct panthor_vm *vm,
 			 size_t size, u32 bo_flags, u32 vm_map_flags,
 			 u64 gpu_va, const char *name)
 {
 	struct drm_gem_shmem_object *obj;
 	struct panthor_kernel_bo *kbo;
 	struct panthor_gem_object *bo;
 	u32 debug_flags = PANTHOR_DEBUGFS_GEM_USAGE_FLAG_KERNEL;
 	int ret;

 	if (drm_WARN_ON(&ptdev->base, !vm))
 		return ERR_PTR(-EINVAL);

 	kbo = kzalloc(sizeof(*kbo), GFP_KERNEL);
 	if (!kbo)
 		return ERR_PTR(-ENOMEM);

 	obj = drm_gem_shmem_create(&ptdev->base, size);
 	if (IS_ERR(obj)) {
 		ret = PTR_ERR(obj);
 		goto err_free_bo;
 	}

 	bo = to_panthor_bo(&obj->base);
 	kbo->obj = &obj->base;
 	bo->flags = bo_flags;
 	bo->exclusive_vm_root_gem = panthor_vm_root_gem(vm);
 	drm_gem_object_get(bo->exclusive_vm_root_gem);
 	bo->base.base.resv = bo->exclusive_vm_root_gem->resv;

 	if (vm == panthor_fw_vm(ptdev))
 		debug_flags |= PANTHOR_DEBUGFS_GEM_USAGE_FLAG_FW_MAPPED;

 	panthor_gem_kernel_bo_set_label(kbo, name);
 	panthor_gem_debugfs_set_usage_flags(to_panthor_bo(kbo->obj), debug_flags);

 	/* The system and GPU MMU page size might differ, which becomes a
 	 * problem for FW sections that need to be mapped at explicit address
 	 * since our PAGE_SIZE alignment might cover a VA range that's
 	 * expected to be used for another section.
 	 * Make sure we never map more than we need.
 	 */
 	size = ALIGN(size, panthor_vm_page_size(vm));
 	ret = panthor_vm_alloc_va(vm, gpu_va, size, &kbo->va_node);
 	if (ret)
 		goto err_put_obj;

 	ret = panthor_vm_map_bo_range(vm, bo, 0, size, kbo->va_node.start, vm_map_flags);
 	if (ret)
 		goto err_free_va;

 	kbo->vm = panthor_vm_get(vm);
 	return kbo;

 err_free_va:
 	panthor_vm_free_va(vm, &kbo->va_node);

 err_put_obj:
 	drm_gem_object_put(&obj->base);

 err_free_bo:
 	kfree(kbo);
 	return ERR_PTR(ret);
 }

 static struct dma_buf *
 panthor_gem_prime_export(struct drm_gem_object *obj, int flags)
 {
 	/* We can't export GEMs that have an exclusive VM. */
 	if (to_panthor_bo(obj)->exclusive_vm_root_gem)
 		return ERR_PTR(-EINVAL);

 	return drm_gem_prime_export(obj, flags);
 }

 static enum drm_gem_object_status panthor_gem_status(struct drm_gem_object *obj)
 {
 	struct panthor_gem_object *bo = to_panthor_bo(obj);
 	enum drm_gem_object_status res = 0;

 	if (drm_gem_is_imported(&bo->base.base) || bo->base.pages)
 		res |= DRM_GEM_OBJECT_RESIDENT;

 	return res;
 }

 static const struct drm_gem_object_funcs panthor_gem_funcs = {
 	.free = panthor_gem_free_object,
 	.print_info = drm_gem_shmem_object_print_info,
 	.pin = drm_gem_shmem_object_pin,
 	.unpin = drm_gem_shmem_object_unpin,
 	.get_sg_table = drm_gem_shmem_object_get_sg_table,
 	.vmap = drm_gem_shmem_object_vmap,
 	.vunmap = drm_gem_shmem_object_vunmap,
 	.mmap = drm_gem_shmem_object_mmap,
 	.status = panthor_gem_status,
 	.export = panthor_gem_prime_export,
 	.vm_ops = &drm_gem_shmem_vm_ops,
 };

 /**
  * panthor_gem_create_object - Implementation of driver->gem_create_object.
  * @ddev: DRM device
  * @size: Size in bytes of the memory the object will reference
  *
  * This lets the GEM helpers allocate object structs for us, and keep
  * our BO stats correct.
  */
 struct drm_gem_object *panthor_gem_create_object(struct drm_device *ddev, size_t size)
 {
 	struct panthor_device *ptdev = container_of(ddev, struct panthor_device, base);
 	struct panthor_gem_object *obj;

 	obj = kzalloc(sizeof(*obj), GFP_KERNEL);
 	if (!obj)
 		return ERR_PTR(-ENOMEM);

 	obj->base.base.funcs = &panthor_gem_funcs;
 	obj->base.map_wc = !ptdev->coherent;
 	mutex_init(&obj->label.lock);

 	panthor_gem_debugfs_bo_init(obj);

 	return &obj->base.base;
 }

 /**
  * panthor_gem_create_with_handle() - Create a GEM object and attach it to a handle.
  * @file: DRM file.
  * @ddev: DRM device.
  * @exclusive_vm: Exclusive VM. Not NULL if the GEM object can't be shared.
  * @size: Size of the GEM object to allocate.
  * @flags: Combination of drm_panthor_bo_flags flags.
  * @handle: Pointer holding the handle pointing to the new GEM object.
  *
  * Return: Zero on success
  */
 int
 panthor_gem_create_with_handle(struct drm_file *file,
 			       struct drm_device *ddev,
 			       struct panthor_vm *exclusive_vm,
 			       u64 *size, u32 flags, u32 *handle)
 {
 	int ret;
 	struct drm_gem_shmem_object *shmem;
 	struct panthor_gem_object *bo;

 	shmem = drm_gem_shmem_create(ddev, *size);
 	if (IS_ERR(shmem))
 		return PTR_ERR(shmem);

 	bo = to_panthor_bo(&shmem->base);
 	bo->flags = flags;

 	if (exclusive_vm) {
 		bo->exclusive_vm_root_gem = panthor_vm_root_gem(exclusive_vm);
 		drm_gem_object_get(bo->exclusive_vm_root_gem);
 		bo->base.base.resv = bo->exclusive_vm_root_gem->resv;
 	}

 	panthor_gem_debugfs_set_usage_flags(bo, 0);

 	/* If this is a write-combine mapping, we query the sgt to force a CPU
 	 * cache flush (dma_map_sgtable() is called when the sgt is created).
 	 * This ensures the zero-ing is visible to any uncached mapping created
 	 * by vmap/mmap.
 	 * FIXME: Ideally this should be done when pages are allocated, not at
 	 * BO creation time.
 	 */
 	if (shmem->map_wc) {
 		struct sg_table *sgt;

 		sgt = drm_gem_shmem_get_pages_sgt(shmem);
 		if (IS_ERR(sgt)) {
 			ret = PTR_ERR(sgt);
 			goto out_put_gem;
 		}
 	}

 	/*
 	 * Allocate an id of idr table where the obj is registered
 	 * and handle has the id what user can see.
 	 */
 	ret = drm_gem_handle_create(file, &shmem->base, handle);
 	if (!ret)
 		*size = bo->base.base.size;

 out_put_gem:
 	/* drop reference from allocate - handle holds it now. */
 	drm_gem_object_put(&shmem->base);

 	return ret;
 }

 void
 panthor_gem_bo_set_label(struct drm_gem_object *obj, const char *label)
 {
 	struct panthor_gem_object *bo = to_panthor_bo(obj);
 	const char *old_label;

 	scoped_guard(mutex, &bo->label.lock) {
 		old_label = bo->label.str;
 		bo->label.str = label;
 	}

 	kfree_const(old_label);
 }

 void
 panthor_gem_kernel_bo_set_label(struct panthor_kernel_bo *bo, const char *label)
 {
 	const char *str;

 	/* We should never attempt labelling a UM-exposed GEM object */
 	if (drm_WARN_ON(bo->obj->dev, bo->obj->handle_count > 0))
 		return;

 	if (!label)
 		return;

 	str = kstrdup_const(label, GFP_KERNEL);
 	if (!str) {
 		/* Failing to allocate memory for a label isn't a fatal condition */
 		drm_warn(bo->obj->dev, "Not enough memory to allocate BO label");
 		return;
 	}

 	panthor_gem_bo_set_label(bo->obj, str);
 }

 #ifdef CONFIG_DEBUG_FS
 struct gem_size_totals {
 	size_t size;
 	size_t resident;
 	size_t reclaimable;
 };

 static void panthor_gem_debugfs_print_flag_names(struct seq_file *m)
 {
 	int len;
 	int i;

 	static const char * const gem_state_flags_names[] = {
 		[PANTHOR_DEBUGFS_GEM_STATE_IMPORTED_BIT] = "imported",
 		[PANTHOR_DEBUGFS_GEM_STATE_EXPORTED_BIT] = "exported",
 	};

 	static const char * const gem_usage_flags_names[] = {
 		[PANTHOR_DEBUGFS_GEM_USAGE_KERNEL_BIT] = "kernel",
 		[PANTHOR_DEBUGFS_GEM_USAGE_FW_MAPPED_BIT] = "fw-mapped",
 	};

 	seq_puts(m, "GEM state flags: ");
 	for (i = 0, len = ARRAY_SIZE(gem_state_flags_names); i < len; i++) {
 		if (!gem_state_flags_names[i])
 			continue;
 		seq_printf(m, "%s (0x%x)%s", gem_state_flags_names[i],
 			   (u32)BIT(i), (i < len - 1) ? ", " : "\n");
 	}

 	seq_puts(m, "GEM usage flags: ");
 	for (i = 0, len = ARRAY_SIZE(gem_usage_flags_names); i < len; i++) {
 		if (!gem_usage_flags_names[i])
 			continue;
 		seq_printf(m, "%s (0x%x)%s", gem_usage_flags_names[i],
 			   (u32)BIT(i), (i < len - 1) ? ", " : "\n\n");
 	}
 }

 static void panthor_gem_debugfs_bo_print(struct panthor_gem_object *bo,
 					 struct seq_file *m,
 					 struct gem_size_totals *totals)
 {
 	unsigned int refcount = kref_read(&bo->base.base.refcount);
 	char creator_info[32] = {};
 	size_t resident_size;
 	u32 gem_usage_flags = bo->debugfs.flags;
 	u32 gem_state_flags = 0;

 	/* Skip BOs being destroyed. */
 	if (!refcount)
 		return;

 	resident_size = bo->base.pages ? bo->base.base.size : 0;

 	snprintf(creator_info, sizeof(creator_info),
 		 "%s/%d", bo->debugfs.creator.process_name, bo->debugfs.creator.tgid);
 	seq_printf(m, "%-32s%-16d%-16d%-16zd%-16zd0x%-16lx",
 		   creator_info,
 		   bo->base.base.name,
 		   refcount,
 		   bo->base.base.size,
 		   resident_size,
 		   drm_vma_node_start(&bo->base.base.vma_node));

 	if (bo->base.base.import_attach)
 		gem_state_flags |= PANTHOR_DEBUGFS_GEM_STATE_FLAG_IMPORTED;
 	if (bo->base.base.dma_buf)
 		gem_state_flags |= PANTHOR_DEBUGFS_GEM_STATE_FLAG_EXPORTED;

 	seq_printf(m, "0x%-8x 0x%-10x", gem_state_flags, gem_usage_flags);

 	scoped_guard(mutex, &bo->label.lock) {
 		seq_printf(m, "%s\n", bo->label.str ? : "");
 	}

 	totals->size += bo->base.base.size;
 	totals->resident += resident_size;
 	if (bo->base.madv > 0)
 		totals->reclaimable += resident_size;
 }

 void panthor_gem_debugfs_print_bos(struct panthor_device *ptdev,
 				   struct seq_file *m)
 {
 	struct gem_size_totals totals = {0};
 	struct panthor_gem_object *bo;

 	panthor_gem_debugfs_print_flag_names(m);

 	seq_puts(m, "created-by                      global-name     refcount        size            resident-size   file-offset       state      usage       label\n");
 	seq_puts(m, "----------------------------------------------------------------------------------------------------------------------------------------------\n");

 	scoped_guard(mutex, &ptdev->gems.lock) {
 		list_for_each_entry(bo, &ptdev->gems.node, debugfs.node) {
 			panthor_gem_debugfs_bo_print(bo, m, &totals);
 		}
 	}

 	seq_puts(m, "==============================================================================================================================================\n");
 	seq_printf(m, "Total size: %zd, Total resident: %zd, Total reclaimable: %zd\n",
 		   totals.size, totals.resident, totals.reclaimable);
 }
 #endif
	// SPDX-License-Identifier: GPL-2.0 or MIT
	/* Copyright 2019 Linaro, Ltd, Rob Herring <robh@kernel.org> */
	/* Copyright 2023 Collabora ltd. */

	#include <linux/cleanup.h>
	#include <linux/dma-buf.h>
	#include <linux/dma-mapping.h>
	#include <linux/err.h>
	#include <linux/slab.h>

	#include <drm/drm_print.h>
	#include <drm/panthor_drm.h>

	#include "panthor_device.h"
	#include "panthor_fw.h"
	#include "panthor_gem.h"
	#include "panthor_mmu.h"

	#ifdef CONFIG_DEBUG_FS
	static void panthor_gem_debugfs_bo_init(struct panthor_gem_object *bo)
	{
	INIT_LIST_HEAD(&bo->debugfs.node);
	}

	static void panthor_gem_debugfs_bo_add(struct panthor_gem_object *bo)
	{
	struct panthor_device *ptdev = container_of(bo->base.base.dev,
	struct panthor_device, base);

	bo->debugfs.creator.tgid = current->group_leader->pid;
	get_task_comm(bo->debugfs.creator.process_name, current->group_leader);

	mutex_lock(&ptdev->gems.lock);
	list_add_tail(&bo->debugfs.node, &ptdev->gems.node);
	mutex_unlock(&ptdev->gems.lock);
	}

	static void panthor_gem_debugfs_bo_rm(struct panthor_gem_object *bo)
	{
	struct panthor_device *ptdev = container_of(bo->base.base.dev,
	struct panthor_device, base);

	if (list_empty(&bo->debugfs.node))
	return;

	mutex_lock(&ptdev->gems.lock);
	list_del_init(&bo->debugfs.node);
	mutex_unlock(&ptdev->gems.lock);
	}

	static void panthor_gem_debugfs_set_usage_flags(struct panthor_gem_object *bo, u32 usage_flags)
	{
	bo->debugfs.flags = usage_flags;
	panthor_gem_debugfs_bo_add(bo);
	}
	#else
	static void panthor_gem_debugfs_bo_rm(struct panthor_gem_object *bo) {}
	static void panthor_gem_debugfs_set_usage_flags(struct panthor_gem_object *bo, u32 usage_flags) {}
	static void panthor_gem_debugfs_bo_init(struct panthor_gem_object *bo) {}
	#endif

	static void panthor_gem_free_object(struct drm_gem_object *obj)
	{
	struct panthor_gem_object *bo = to_panthor_bo(obj);
	struct drm_gem_object *vm_root_gem = bo->exclusive_vm_root_gem;

	panthor_gem_debugfs_bo_rm(bo);

	/*
	* Label might have been allocated with kstrdup_const(),
	* we need to take that into account when freeing the memory
	*/
	kfree_const(bo->label.str);

	mutex_destroy(&bo->label.lock);

	drm_gem_free_mmap_offset(&bo->base.base);
	drm_gem_shmem_free(&bo->base);
	drm_gem_object_put(vm_root_gem);
	}

	/**
	* panthor_kernel_bo_destroy() - Destroy a kernel buffer object
	* @bo: Kernel buffer object to destroy. If NULL or an ERR_PTR(), the destruction
	* is skipped.
	*/
	void panthor_kernel_bo_destroy(struct panthor_kernel_bo *bo)
	{
	struct panthor_vm *vm;

	if (IS_ERR_OR_NULL(bo))
	return;

	vm = bo->vm;
	panthor_kernel_bo_vunmap(bo);

	drm_WARN_ON(bo->obj->dev,
	to_panthor_bo(bo->obj)->exclusive_vm_root_gem != panthor_vm_root_gem(vm));
	panthor_vm_unmap_range(vm, bo->va_node.start, bo->va_node.size);
	panthor_vm_free_va(vm, &bo->va_node);
	drm_gem_object_put(bo->obj);
	panthor_vm_put(vm);
	kfree(bo);
	}

	/**
	* panthor_kernel_bo_create() - Create and map a GEM object to a VM
	* @ptdev: Device.
	* @vm: VM to map the GEM to. If NULL, the kernel object is not GPU mapped.
	* @size: Size of the buffer object.
	* @bo_flags: Combination of drm_panthor_bo_flags flags.
	* @vm_map_flags: Combination of drm_panthor_vm_bind_op_flags (only those
	* that are related to map operations).
	* @gpu_va: GPU address assigned when mapping to the VM.
	* If gpu_va == PANTHOR_VM_KERNEL_AUTO_VA, the virtual address will be
	* automatically allocated.
	* @name: Descriptive label of the BO's contents
	*
	* Return: A valid pointer in case of success, an ERR_PTR() otherwise.
	*/
	struct panthor_kernel_bo *
	panthor_kernel_bo_create(struct panthor_device ptdev, struct panthor_vm vm,
	size_t size, u32 bo_flags, u32 vm_map_flags,
	u64 gpu_va, const char *name)
	{
	struct drm_gem_shmem_object *obj;
	struct panthor_kernel_bo *kbo;
	struct panthor_gem_object *bo;
	u32 debug_flags = PANTHOR_DEBUGFS_GEM_USAGE_FLAG_KERNEL;
	int ret;

	if (drm_WARN_ON(&ptdev->base, !vm))
	return ERR_PTR(-EINVAL);

	kbo = kzalloc(sizeof(*kbo), GFP_KERNEL);
	if (!kbo)
	return ERR_PTR(-ENOMEM);

	obj = drm_gem_shmem_create(&ptdev->base, size);
	if (IS_ERR(obj)) {
	ret = PTR_ERR(obj);
	goto err_free_bo;
	}

	bo = to_panthor_bo(&obj->base);
	kbo->obj = &obj->base;
	bo->flags = bo_flags;
	bo->exclusive_vm_root_gem = panthor_vm_root_gem(vm);
	drm_gem_object_get(bo->exclusive_vm_root_gem);
	bo->base.base.resv = bo->exclusive_vm_root_gem->resv;

	if (vm == panthor_fw_vm(ptdev))
	debug_flags \|= PANTHOR_DEBUGFS_GEM_USAGE_FLAG_FW_MAPPED;

	panthor_gem_kernel_bo_set_label(kbo, name);
	panthor_gem_debugfs_set_usage_flags(to_panthor_bo(kbo->obj), debug_flags);

	/* The system and GPU MMU page size might differ, which becomes a
	* problem for FW sections that need to be mapped at explicit address
	* since our PAGE_SIZE alignment might cover a VA range that's
	* expected to be used for another section.
	* Make sure we never map more than we need.
	*/
	size = ALIGN(size, panthor_vm_page_size(vm));
	ret = panthor_vm_alloc_va(vm, gpu_va, size, &kbo->va_node);
	if (ret)
	goto err_put_obj;

	ret = panthor_vm_map_bo_range(vm, bo, 0, size, kbo->va_node.start, vm_map_flags);
	if (ret)
	goto err_free_va;

	kbo->vm = panthor_vm_get(vm);
	return kbo;

	err_free_va:
	panthor_vm_free_va(vm, &kbo->va_node);

	err_put_obj:
	drm_gem_object_put(&obj->base);

	err_free_bo:
	kfree(kbo);
	return ERR_PTR(ret);
	}

	static struct dma_buf *
	panthor_gem_prime_export(struct drm_gem_object *obj, int flags)
	{
	/* We can't export GEMs that have an exclusive VM. */
	if (to_panthor_bo(obj)->exclusive_vm_root_gem)
	return ERR_PTR(-EINVAL);

	return drm_gem_prime_export(obj, flags);
	}

	static enum drm_gem_object_status panthor_gem_status(struct drm_gem_object *obj)
	{
	struct panthor_gem_object *bo = to_panthor_bo(obj);
	enum drm_gem_object_status res = 0;

	if (drm_gem_is_imported(&bo->base.base) \|\| bo->base.pages)
	res \|= DRM_GEM_OBJECT_RESIDENT;

	return res;
	}

	static const struct drm_gem_object_funcs panthor_gem_funcs = {
	.free = panthor_gem_free_object,
	.print_info = drm_gem_shmem_object_print_info,
	.pin = drm_gem_shmem_object_pin,
	.unpin = drm_gem_shmem_object_unpin,
	.get_sg_table = drm_gem_shmem_object_get_sg_table,
	.vmap = drm_gem_shmem_object_vmap,
	.vunmap = drm_gem_shmem_object_vunmap,
	.mmap = drm_gem_shmem_object_mmap,
	.status = panthor_gem_status,
	.export = panthor_gem_prime_export,
	.vm_ops = &drm_gem_shmem_vm_ops,
	};

	/**
	* panthor_gem_create_object - Implementation of driver->gem_create_object.
	* @ddev: DRM device
	* @size: Size in bytes of the memory the object will reference
	*
	* This lets the GEM helpers allocate object structs for us, and keep
	* our BO stats correct.
	*/
	struct drm_gem_object panthor_gem_create_object(struct drm_device ddev, size_t size)
	{
	struct panthor_device *ptdev = container_of(ddev, struct panthor_device, base);
	struct panthor_gem_object *obj;

	obj = kzalloc(sizeof(*obj), GFP_KERNEL);
	if (!obj)
	return ERR_PTR(-ENOMEM);

	obj->base.base.funcs = &panthor_gem_funcs;
	obj->base.map_wc = !ptdev->coherent;
	mutex_init(&obj->label.lock);

	panthor_gem_debugfs_bo_init(obj);

	return &obj->base.base;
	}

	/**
	* panthor_gem_create_with_handle() - Create a GEM object and attach it to a handle.
	* @file: DRM file.
	* @ddev: DRM device.
	* @exclusive_vm: Exclusive VM. Not NULL if the GEM object can't be shared.
	* @size: Size of the GEM object to allocate.
	* @flags: Combination of drm_panthor_bo_flags flags.
	* @handle: Pointer holding the handle pointing to the new GEM object.
	*
	* Return: Zero on success
	*/
	int
	panthor_gem_create_with_handle(struct drm_file *file,
	struct drm_device *ddev,
	struct panthor_vm *exclusive_vm,
	u64 size, u32 flags, u32 handle)
	{
	int ret;
	struct drm_gem_shmem_object *shmem;
	struct panthor_gem_object *bo;

	shmem = drm_gem_shmem_create(ddev, *size);
	if (IS_ERR(shmem))
	return PTR_ERR(shmem);

	bo = to_panthor_bo(&shmem->base);
	bo->flags = flags;

	if (exclusive_vm) {
	bo->exclusive_vm_root_gem = panthor_vm_root_gem(exclusive_vm);
	drm_gem_object_get(bo->exclusive_vm_root_gem);
	bo->base.base.resv = bo->exclusive_vm_root_gem->resv;
	}

	panthor_gem_debugfs_set_usage_flags(bo, 0);

	/* If this is a write-combine mapping, we query the sgt to force a CPU
	* cache flush (dma_map_sgtable() is called when the sgt is created).
	* This ensures the zero-ing is visible to any uncached mapping created
	* by vmap/mmap.
	* FIXME: Ideally this should be done when pages are allocated, not at
	* BO creation time.
	*/
	if (shmem->map_wc) {
	struct sg_table *sgt;

	sgt = drm_gem_shmem_get_pages_sgt(shmem);
	if (IS_ERR(sgt)) {
	ret = PTR_ERR(sgt);
	goto out_put_gem;
	}
	}

	/*
	* Allocate an id of idr table where the obj is registered
	* and handle has the id what user can see.
	*/
	ret = drm_gem_handle_create(file, &shmem->base, handle);
	if (!ret)
	*size = bo->base.base.size;

	out_put_gem:
	/* drop reference from allocate - handle holds it now. */
	drm_gem_object_put(&shmem->base);

	return ret;
	}

	void
	panthor_gem_bo_set_label(struct drm_gem_object obj, const char label)
	{
	struct panthor_gem_object *bo = to_panthor_bo(obj);
	const char *old_label;

	scoped_guard(mutex, &bo->label.lock) {
	old_label = bo->label.str;
	bo->label.str = label;
	}

	kfree_const(old_label);
	}

	void
	panthor_gem_kernel_bo_set_label(struct panthor_kernel_bo bo, const char label)
	{
	const char *str;

	/* We should never attempt labelling a UM-exposed GEM object */
	if (drm_WARN_ON(bo->obj->dev, bo->obj->handle_count > 0))
	return;

	if (!label)
	return;

	str = kstrdup_const(label, GFP_KERNEL);
	if (!str) {
	/* Failing to allocate memory for a label isn't a fatal condition */
	drm_warn(bo->obj->dev, "Not enough memory to allocate BO label");
	return;
	}

	panthor_gem_bo_set_label(bo->obj, str);
	}

	#ifdef CONFIG_DEBUG_FS
	struct gem_size_totals {
	size_t size;
	size_t resident;
	size_t reclaimable;
	};

	static void panthor_gem_debugfs_print_flag_names(struct seq_file *m)
	{
	int len;
	int i;

	static const char * const gem_state_flags_names[] = {
	[PANTHOR_DEBUGFS_GEM_STATE_IMPORTED_BIT] = "imported",
	[PANTHOR_DEBUGFS_GEM_STATE_EXPORTED_BIT] = "exported",
	};

	static const char * const gem_usage_flags_names[] = {
	[PANTHOR_DEBUGFS_GEM_USAGE_KERNEL_BIT] = "kernel",
	[PANTHOR_DEBUGFS_GEM_USAGE_FW_MAPPED_BIT] = "fw-mapped",
	};

	seq_puts(m, "GEM state flags: ");
	for (i = 0, len = ARRAY_SIZE(gem_state_flags_names); i < len; i++) {
	if (!gem_state_flags_names[i])
	continue;
	seq_printf(m, "%s (0x%x)%s", gem_state_flags_names[i],
	(u32)BIT(i), (i < len - 1) ? ", " : "\n");
	}

	seq_puts(m, "GEM usage flags: ");
	for (i = 0, len = ARRAY_SIZE(gem_usage_flags_names); i < len; i++) {
	if (!gem_usage_flags_names[i])
	continue;
	seq_printf(m, "%s (0x%x)%s", gem_usage_flags_names[i],
	(u32)BIT(i), (i < len - 1) ? ", " : "\n\n");
	}
	}

	static void panthor_gem_debugfs_bo_print(struct panthor_gem_object *bo,
	struct seq_file *m,
	struct gem_size_totals *totals)
	{
	unsigned int refcount = kref_read(&bo->base.base.refcount);
	char creator_info[32] = {};
	size_t resident_size;
	u32 gem_usage_flags = bo->debugfs.flags;
	u32 gem_state_flags = 0;

	/* Skip BOs being destroyed. */
	if (!refcount)
	return;

	resident_size = bo->base.pages ? bo->base.base.size : 0;

	snprintf(creator_info, sizeof(creator_info),
	"%s/%d", bo->debugfs.creator.process_name, bo->debugfs.creator.tgid);
	seq_printf(m, "%-32s%-16d%-16d%-16zd%-16zd0x%-16lx",
	creator_info,
	bo->base.base.name,
	refcount,
	bo->base.base.size,
	resident_size,
	drm_vma_node_start(&bo->base.base.vma_node));

	if (bo->base.base.import_attach)
	gem_state_flags \|= PANTHOR_DEBUGFS_GEM_STATE_FLAG_IMPORTED;
	if (bo->base.base.dma_buf)
	gem_state_flags \|= PANTHOR_DEBUGFS_GEM_STATE_FLAG_EXPORTED;

	seq_printf(m, "0x%-8x 0x%-10x", gem_state_flags, gem_usage_flags);

	scoped_guard(mutex, &bo->label.lock) {
	seq_printf(m, "%s\n", bo->label.str ? : "");
	}

	totals->size += bo->base.base.size;
	totals->resident += resident_size;
	if (bo->base.madv > 0)
	totals->reclaimable += resident_size;
	}

	void panthor_gem_debugfs_print_bos(struct panthor_device *ptdev,
	struct seq_file *m)
	{
	struct gem_size_totals totals = {0};
	struct panthor_gem_object *bo;

	panthor_gem_debugfs_print_flag_names(m);

	seq_puts(m, "created-by global-name refcount size resident-size file-offset state usage label\n");
	seq_puts(m, "----------------------------------------------------------------------------------------------------------------------------------------------\n");

	scoped_guard(mutex, &ptdev->gems.lock) {
	list_for_each_entry(bo, &ptdev->gems.node, debugfs.node) {
	panthor_gem_debugfs_bo_print(bo, m, &totals);
	}
	}

	seq_puts(m, "==============================================================================================================================================\n");
	seq_printf(m, "Total size: %zd, Total resident: %zd, Total reclaimable: %zd\n",
	totals.size, totals.resident, totals.reclaimable);
	}
	#endif