path: root/drivers/gpu/drm/amd/amdkfd/kfd_process.c

/*
 * Copyright 2014 Advanced Micro Devices, Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 */

#include <linux/mutex.h>
#include <linux/log2.h>
#include <linux/sched.h>
#include <linux/sched/mm.h>
#include <linux/sched/task.h>
#include <linux/slab.h>
#include <linux/amd-iommu.h>
#include <linux/notifier.h>
#include <linux/compat.h>
#include <linux/mman.h>
#include <linux/file.h>
#include "amdgpu_amdkfd.h"

struct mm_struct;

#include "kfd_priv.h"
#include "kfd_device_queue_manager.h"
#include "kfd_dbgmgr.h"
#include "kfd_iommu.h"

/*
 * List of struct kfd_process (field kfd_process).
 * Unique/indexed by mm_struct*
 */
DEFINE_HASHTABLE(kfd_processes_table, KFD_PROCESS_TABLE_SIZE);
static DEFINE_MUTEX(kfd_processes_mutex);

DEFINE_SRCU(kfd_processes_srcu);

/* For process termination handling */
static struct workqueue_struct *kfd_process_wq;

/* Ordered, single-threaded workqueue for restoring evicted
 * processes. Restoring multiple processes concurrently under memory
 * pressure can lead to processes blocking each other from validating
 * their BOs and result in a live-lock situation where processes
 * remain evicted indefinitely.
 */
static struct workqueue_struct *kfd_restore_wq;

static struct kfd_process *find_process(const struct task_struct *thread);
static void kfd_process_ref_release(struct kref *ref);
static struct kfd_process *create_process(const struct task_struct *thread,
					struct file *filep);

static void evict_process_worker(struct work_struct *work);
static void restore_process_worker(struct work_struct *work);

struct kfd_procfs_tree {
	struct kobject *kobj;
};

static struct kfd_procfs_tree procfs;

static ssize_t kfd_procfs_show(struct kobject *kobj, struct attribute *attr,
			       char *buffer)
{
	int val = 0;

	if (strcmp(attr->name, "pasid") == 0) {
		struct kfd_process *p = container_of(attr, struct kfd_process,
						     attr_pasid);
		val = p->pasid;
	} else {
		pr_err("Invalid attribute");
		return -EINVAL;
	}

	return snprintf(buffer, PAGE_SIZE, "%d\n", val);
}

static void kfd_procfs_kobj_release(struct kobject *kobj)
{
	kfree(kobj);
}

static const struct sysfs_ops kfd_procfs_ops = {
	.show = kfd_procfs_show,
};

static struct kobj_type procfs_type = {
	.release = kfd_procfs_kobj_release,
	.sysfs_ops = &kfd_procfs_ops,
};

void kfd_procfs_init(void)
{
	int ret = 0;

	procfs.kobj = kfd_alloc_struct(procfs.kobj);
	if (!procfs.kobj)
		return;

	ret = kobject_init_and_add(procfs.kobj, &procfs_type,
				   &kfd_device->kobj, "proc");
	if (ret) {
		pr_warn("Could not create procfs proc folder");
		/* If we fail to create the procfs, clean up */
		kfd_procfs_shutdown();
	}
}

void kfd_procfs_shutdown(void)
{
	if (procfs.kobj) {
		kobject_del(procfs.kobj);
		kobject_put(procfs.kobj);
		procfs.kobj = NULL;
	}
}

int kfd_process_create_wq(void)
{
	if (!kfd_process_wq)
		kfd_process_wq = alloc_workqueue("kfd_process_wq", 0, 0);
	if (!kfd_restore_wq)
		kfd_restore_wq = alloc_ordered_workqueue("kfd_restore_wq", 0);

	if (!kfd_process_wq || !kfd_restore_wq) {
		kfd_process_destroy_wq();