Orange Pi5 kernel

/* SPDX-License-Identifier: GPL-2.0 */
/* Copyright (C) 2019 Arm Ltd.
 *
 * Based on msm_gem_freedreno.c:
 * Copyright (C) 2016 Red Hat
 * Author: Rob Clark <robdclark@gmail.com>
 */
 
#include <linux/list.h>
 
#include <drm/drm_device.h>
#include <drm/drm_gem_shmem_helper.h>
 
#include "panfrost_device.h"
#include "panfrost_gem.h"
#include "panfrost_mmu.h"
 
static unsigned long
panfrost_gem_shrinker_count(struct shrinker *shrinker, struct shrink_control *sc)
{
<------>struct panfrost_device *pfdev =
<------><------>container_of(shrinker, struct panfrost_device, shrinker);
<------>struct drm_gem_shmem_object *shmem;
<------>unsigned long count = 0;
 
<------>if (!mutex_trylock(&pfdev->shrinker_lock))
<------><------>return 0;
 
<------>list_for_each_entry(shmem, &pfdev->shrinker_list, madv_list) {
<------><------>if (drm_gem_shmem_is_purgeable(shmem))
<------><------><------>count += shmem->base.size >> PAGE_SHIFT;
<------>}
 
<------>mutex_unlock(&pfdev->shrinker_lock);
 
<------>return count;
}
 
static bool panfrost_gem_purge(struct drm_gem_object *obj)
{
<------>struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
<------>struct panfrost_gem_object *bo = to_panfrost_bo(obj);
<------>bool ret = false;
 
<------>if (atomic_read(&bo->gpu_usecount))
<------><------>return false;
 
<------>if (!mutex_trylock(&bo->mappings.lock))
<------><------>return false;
 
<------>if (!mutex_trylock(&shmem->pages_lock))
<------><------>goto unlock_mappings;
 
<------>panfrost_gem_teardown_mappings_locked(bo);
<------>drm_gem_shmem_purge_locked(obj);
<------>ret = true;
 
<------>mutex_unlock(&shmem->pages_lock);
 
unlock_mappings:
<------>mutex_unlock(&bo->mappings.lock);
<------>return ret;
}
 
static unsigned long
panfrost_gem_shrinker_scan(struct shrinker *shrinker, struct shrink_control *sc)
{
<------>struct panfrost_device *pfdev =
<------><------>container_of(shrinker, struct panfrost_device, shrinker);
<------>struct drm_gem_shmem_object *shmem, *tmp;
<------>unsigned long freed = 0;
 
<------>if (!mutex_trylock(&pfdev->shrinker_lock))
<------><------>return SHRINK_STOP;
 
<------>list_for_each_entry_safe(shmem, tmp, &pfdev->shrinker_list, madv_list) {
<------><------>if (freed >= sc->nr_to_scan)
<------><------><------>break;
<------><------>if (drm_gem_shmem_is_purgeable(shmem) &&
<------><------>    panfrost_gem_purge(&shmem->base)) {
<------><------><------>freed += shmem->base.size >> PAGE_SHIFT;
<------><------><------>list_del_init(&shmem->madv_list);
<------><------>}
<------>}
 
<------>mutex_unlock(&pfdev->shrinker_lock);
 
<------>if (freed > 0)
<------><------>pr_info_ratelimited("Purging %lu bytes\n", freed << PAGE_SHIFT);
 
<------>return freed;
}
 
/**
 * panfrost_gem_shrinker_init - Initialize panfrost shrinker
 * @dev: DRM device
 *
 * This function registers and sets up the panfrost shrinker.
 */
void panfrost_gem_shrinker_init(struct drm_device *dev)
{
<------>struct panfrost_device *pfdev = dev->dev_private;
<------>pfdev->shrinker.count_objects = panfrost_gem_shrinker_count;
<------>pfdev->shrinker.scan_objects = panfrost_gem_shrinker_scan;
<------>pfdev->shrinker.seeks = DEFAULT_SEEKS;
<------>WARN_ON(register_shrinker(&pfdev->shrinker));
}
 
/**
 * panfrost_gem_shrinker_cleanup - Clean up panfrost shrinker
 * @dev: DRM device
 *
 * This function unregisters the panfrost shrinker.
 */
void panfrost_gem_shrinker_cleanup(struct drm_device *dev)
{
<------>struct panfrost_device *pfdev = dev->dev_private;
 
<------>if (pfdev->shrinker.nr_deferred) {
<------><------>unregister_shrinker(&pfdev->shrinker);
<------>}
}