linux/drivers/dax/kmem.c

// SPDX-License-Identifier: GPL-2.0
/* Copyright(c) 2016-2019 Intel Corporation. All rights reserved. */
#include <linux/memremap.h>
#include <linux/pagemap.h>
#include <linux/memory.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/pfn_t.h>
#include <linux/slab.h>
#include <linux/dax.h>
#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/mman.h>
#include <linux/memory-tiers.h>
#include <linux/memory_hotplug.h>
#include "dax-private.h"
#include "bus.h"

/*
 * Default abstract distance assigned to the NUMA node onlined
 * by DAX/kmem if the low level platform driver didn't initialize
 * one for this NUMA node.
 */
#define MEMTIER_DEFAULT_DAX_ADISTANCE …

/* Memory resource name used for add_memory_driver_managed(). */
static const char *kmem_name;
/* Set if any memory will remain added when the driver will be unloaded. */
static bool any_hotremove_failed;

static int dax_kmem_range(struct dev_dax *dev_dax, int i, struct range *r)
{ … }

struct dax_kmem_data { … };

static DEFINE_MUTEX(kmem_memory_type_lock);
static LIST_HEAD(kmem_memory_types);

static struct memory_dev_type *kmem_find_alloc_memory_type(int adist)
{ … }

static void kmem_put_memory_types(void)
{ … }

static int dev_dax_kmem_probe(struct dev_dax *dev_dax)
{ … }

#ifdef CONFIG_MEMORY_HOTREMOVE
static void dev_dax_kmem_remove(struct dev_dax *dev_dax)
{ … }
#else
static void dev_dax_kmem_remove(struct dev_dax *dev_dax)
{
	/*
	 * Without hotremove purposely leak the request_mem_region() for the
	 * device-dax range and return '0' to ->remove() attempts. The removal
	 * of the device from the driver always succeeds, but the region is
	 * permanently pinned as reserved by the unreleased
	 * request_mem_region().
	 */
	any_hotremove_failed = true;
}
#endif /* CONFIG_MEMORY_HOTREMOVE */

static struct dax_device_driver device_dax_kmem_driver = …;

static int __init dax_kmem_init(void)
{ … }

static void __exit dax_kmem_exit(void)
{ … }

MODULE_AUTHOR(…) …;
MODULE_DESCRIPTION(…) …;
MODULE_LICENSE(…) …;
module_init(…) …;
module_exit(dax_kmem_exit);
MODULE_ALIAS_DAX_DEVICE(…);