LXR linux/drivers/nvdimm/e820.c

   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright (c) 2015, Christoph Hellwig.
   4 * Copyright (c) 2015, Intel Corporation.
   5 */
   6#include <linux/platform_device.h>
   7#include <linux/memory_hotplug.h>
   8#include <linux/libnvdimm.h>
   9#include <linux/module.h>
  10
  11static int e820_pmem_remove(struct platform_device *pdev)
  12{
  13        struct nvdimm_bus *nvdimm_bus = platform_get_drvdata(pdev);
  14
  15        nvdimm_bus_unregister(nvdimm_bus);
  16        return 0;
  17}
  18
  19#ifdef CONFIG_MEMORY_HOTPLUG
  20static int e820_range_to_nid(resource_size_t addr)
  21{
  22        return memory_add_physaddr_to_nid(addr);
  23}
  24#else
  25static int e820_range_to_nid(resource_size_t addr)
  26{
  27        return NUMA_NO_NODE;
  28}
  29#endif
  30
  31static int e820_register_one(struct resource *res, void *data)
  32{
  33        struct nd_region_desc ndr_desc;
  34        struct nvdimm_bus *nvdimm_bus = data;
  35
  36        memset(&ndr_desc, 0, sizeof(ndr_desc));
  37        ndr_desc.res = res;
  38        ndr_desc.numa_node = e820_range_to_nid(res->start);
  39        ndr_desc.target_node = ndr_desc.numa_node;
  40        set_bit(ND_REGION_PAGEMAP, &ndr_desc.flags);
  41        if (!nvdimm_pmem_region_create(nvdimm_bus, &ndr_desc))
  42                return -ENXIO;
  43        return 0;
  44}
  45
  46static int e820_pmem_probe(struct platform_device *pdev)
  47{
  48        static struct nvdimm_bus_descriptor nd_desc;
  49        struct device *dev = &pdev->dev;
  50        struct nvdimm_bus *nvdimm_bus;
  51        int rc = -ENXIO;
  52
  53        nd_desc.provider_name = "e820";
  54        nd_desc.module = THIS_MODULE;
  55        nvdimm_bus = nvdimm_bus_register(dev, &nd_desc);
  56        if (!nvdimm_bus)
  57                goto err;
  58        platform_set_drvdata(pdev, nvdimm_bus);
  59
  60        rc = walk_iomem_res_desc(IORES_DESC_PERSISTENT_MEMORY_LEGACY,
  61                        IORESOURCE_MEM, 0, -1, nvdimm_bus, e820_register_one);
  62        if (rc)
  63                goto err;
  64        return 0;
  65err:
  66        nvdimm_bus_unregister(nvdimm_bus);
  67        dev_err(dev, "failed to register legacy persistent memory ranges\n");
  68        return rc;
  69}
  70
  71static struct platform_driver e820_pmem_driver = {
  72        .probe = e820_pmem_probe,
  73        .remove = e820_pmem_remove,
  74        .driver = {
  75                .name = "e820_pmem",
  76        },
  77};
  78
  79module_platform_driver(e820_pmem_driver);
  80
  81MODULE_ALIAS("platform:e820_pmem*");
  82MODULE_LICENSE("GPL v2");
  83MODULE_AUTHOR("Intel Corporation");
  84