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_pmem_probe(struct platform_device *pdev)
  42 {
  43         static struct nvdimm_bus_descriptor nd_desc;
  44         struct device *dev = &pdev->dev;
  45         struct nvdimm_bus *nvdimm_bus;
  46         struct resource *p;
  47
  48         nd_desc.attr_groups = e820_pmem_attribute_groups;
  49         nd_desc.provider_name = "e820";
  50         nvdimm_bus = nvdimm_bus_register(dev, &nd_desc);
  51         if (!nvdimm_bus)
  52                 goto err;
  53         platform_set_drvdata(pdev, nvdimm_bus);
  54
  55         for (p = iomem_resource.child; p ; p = p->sibling) {
  56                 struct nd_region_desc ndr_desc;
  57
  58                 if (strncmp(p->name, "Persistent Memory (legacy)", 26) != 0)
  59                         continue;
  60
  61                 memset(&ndr_desc, 0, sizeof(ndr_desc));
  62                 ndr_desc.res = p;
  63                 ndr_desc.attr_groups = e820_pmem_region_attribute_groups;
  64                 ndr_desc.numa_node = e820_range_to_nid(p->start);
  65                 set_bit(ND_REGION_PAGEMAP, &ndr_desc.flags);
  66                 if (!nvdimm_pmem_region_create(nvdimm_bus, &ndr_desc))
  67                         goto err;
  68         }
  69
  70         return 0;
  71
  72  err:
  73         nvdimm_bus_unregister(nvdimm_bus);
  74         dev_err(dev, "failed to register legacy persistent memory ranges\n");
  75         return -ENXIO;
  76 }
  77
  78 static struct platform_driver e820_pmem_driver = {
  79         .probe = e820_pmem_probe,
  80         .remove = e820_pmem_remove,
  81         .driver = {
  82                 .name = "e820_pmem",
  83         },
  84 };
  85
  86 static __init int e820_pmem_init(void)
  87 {
  88         return platform_driver_register(&e820_pmem_driver);
  89 }
  90
  91 static __exit void e820_pmem_exit(void)
  92 {
  93         platform_driver_unregister(&e820_pmem_driver);
  94 }
  95
  96 MODULE_ALIAS("platform:e820_pmem*");
  97 MODULE_LICENSE("GPL v2");
  98 MODULE_AUTHOR("Intel Corporation");
  99 module_init(e820_pmem_init);
 100 module_exit(e820_pmem_exit);