drivers/dax/hmem.c

// SPDX-License-Identifier: GPL-2.0
#include <linux/platform_device.h>
#include <linux/memregion.h>
#include <linux/module.h>
#include <linux/pfn_t.h>
#include "bus.h"

static int dax_hmem_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct dev_pagemap pgmap = { };
	struct dax_region *dax_region;
	struct memregion_info *mri;
	struct dev_dax *dev_dax;
	struct resource *res;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res)
		return -ENOMEM;

	mri = dev->platform_data;
	memcpy(&pgmap.res, res, sizeof(*res));

	dax_region = alloc_dax_region(dev, pdev->id, res, mri->target_node,
			PMD_SIZE, PFN_DEV|PFN_MAP);
	if (!dax_region)
		return -ENOMEM;

	dev_dax = devm_create_dev_dax(dax_region, 0, &pgmap);
	if (IS_ERR(dev_dax))
		return PTR_ERR(dev_dax);

	/* child dev_dax instances now own the lifetime of the dax_region */
	dax_region_put(dax_region);
	return 0;
}

static int dax_hmem_remove(struct platform_device *pdev)
{
	/* devm handles teardown */
	return 0;
}

static struct platform_driver dax_hmem_driver = {
	.probe = dax_hmem_probe,
	.remove = dax_hmem_remove,
	.driver = {
		.name = "hmem",
	},
};

module_platform_driver(dax_hmem_driver);

MODULE_ALIAS("platform:hmem*");
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Intel Corporation");