drivers/nvdimm/e820.c

   1 /*
   2  * Copyright (c) 2015, Christoph Hellwig.
   3  * Copyright (c) 2015, Intel Corporation.
   4  */
   5 #include <linux/platform_device.h>
   6 #include <linux/memory_hotplug.h>
   7 #include <linux/libnvdimm.h>
   8 #include <linux/module.h>
   9
  10 static const struct attribute_group *e820_pmem_attribute_groups[] = {
  11         &nvdimm_bus_attribute_group,
  12         NULL,
  13 };
  14
  15 static const struct attribute_group *e820_pmem_region_attribute_groups[] = {
  16         &nd_region_attribute_group,
  17         &nd_device_attribute_group,
  18         NULL,
  19 };
  20
  21 static int e820_pmem_remove(struct platform_device *pdev)
  22 {
  23         struct nvdimm_bus *nvdimm_bus = platform_get_drvdata(pdev);
  24
  25         nvdimm_bus_unregister(nvdimm_bus);
  26         return 0;
  27 }
  28
  29 #ifdef CONFIG_MEMORY_HOTPLUG
  30 static int e820_range_to_nid(resource_size_t addr)
  31 {
  32         return memory_add_physaddr_to_nid(addr);
  33 }
  34 #else
  35 static int e820_range_to_nid(resource_size_t addr)
  36 {
  37         return NUMA_NO_NODE;
  38 }
  39 #endif
  40
  41 static int e820_register_one(struct resource *res, void *data)
  42 {
  43         struct nd_region_desc ndr_desc;
  44         struct nvdimm_bus *nvdimm_bus = data;
  45
  46         memset(&ndr_desc, 0, sizeof(ndr_desc));
  47         ndr_desc.res = res;
  48         ndr_desc.attr_groups = e820_pmem_region_attribute_groups;
  49         ndr_desc.numa_node = e820_range_to_nid(res->start);
  50         ndr_desc.target_node = ndr_desc.numa_node;
  51         set_bit(ND_REGION_PAGEMAP, &ndr_desc.flags);
  52         if (!nvdimm_pmem_region_create(nvdimm_bus, &ndr_desc))
  53                 return -ENXIO;
  54         return 0;
  55 }
  56
  57 static int e820_pmem_probe(struct platform_device *pdev)
  58 {
  59         static struct nvdimm_bus_descriptor nd_desc;
  60         struct device *dev = &pdev->dev;
  61         struct nvdimm_bus *nvdimm_bus;
  62         int rc = -ENXIO;
  63
  64         nd_desc.attr_groups = e820_pmem_attribute_groups;
  65         nd_desc.provider_name = "e820";
  66         nd_desc.module = THIS_MODULE;
  67         nvdimm_bus = nvdimm_bus_register(dev, &nd_desc);
  68         if (!nvdimm_bus)
  69                 goto err;
  70         platform_set_drvdata(pdev, nvdimm_bus);
  71
  72         rc = walk_iomem_res_desc(IORES_DESC_PERSISTENT_MEMORY_LEGACY,
  73                         IORESOURCE_MEM, 0, -1, nvdimm_bus, e820_register_one);
  74         if (rc)
  75                 goto err;
  76         return 0;
  77 err:
  78         nvdimm_bus_unregister(nvdimm_bus);
  79         dev_err(dev, "failed to register legacy persistent memory ranges\n");
  80         return rc;
  81 }
  82
  83 static struct platform_driver e820_pmem_driver = {
  84         .probe = e820_pmem_probe,
  85         .remove = e820_pmem_remove,
  86         .driver = {
  87                 .name = "e820_pmem",
  88         },
  89 };
  90
  91 module_platform_driver(e820_pmem_driver);
  92
  93 MODULE_ALIAS("platform:e820_pmem*");
  94 MODULE_LICENSE("GPL v2");
  95 MODULE_AUTHOR("Intel Corporation");