drivers/nvdimm/dax_devs.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright(c) 2013-2016 Intel Corporation. All rights reserved.
   4  */
   5 #include <linux/device.h>
   6 #include <linux/sizes.h>
   7 #include <linux/slab.h>
   8 #include <linux/mm.h>
   9 #include "nd-core.h"
  10 #include "pfn.h"
  11 #include "nd.h"
  12
  13 static void nd_dax_release(struct device *dev)
  14 {
  15         struct nd_region *nd_region = to_nd_region(dev->parent);
  16         struct nd_dax *nd_dax = to_nd_dax(dev);
  17         struct nd_pfn *nd_pfn = &nd_dax->nd_pfn;
  18
  19         dev_dbg(dev, "trace\n");
  20         nd_detach_ndns(dev, &nd_pfn->ndns);
  21         ida_simple_remove(&nd_region->dax_ida, nd_pfn->id);
  22         kfree(nd_pfn->uuid);
  23         kfree(nd_dax);
  24 }
  25
  26 struct nd_dax *to_nd_dax(struct device *dev)
  27 {
  28         struct nd_dax *nd_dax = container_of(dev, struct nd_dax, nd_pfn.dev);
  29
  30         WARN_ON(!is_nd_dax(dev));
  31         return nd_dax;
  32 }
  33 EXPORT_SYMBOL(to_nd_dax);
  34
  35 static const struct device_type nd_dax_device_type = {
  36         .name = "nd_dax",
  37         .release = nd_dax_release,
  38         .groups = nd_pfn_attribute_groups,
  39 };
  40
  41 bool is_nd_dax(struct device *dev)
  42 {
  43         return dev ? dev->type == &nd_dax_device_type : false;
  44 }
  45 EXPORT_SYMBOL(is_nd_dax);
  46
  47 static struct nd_dax *nd_dax_alloc(struct nd_region *nd_region)
  48 {
  49         struct nd_pfn *nd_pfn;
  50         struct nd_dax *nd_dax;
  51         struct device *dev;
  52
  53         nd_dax = kzalloc(sizeof(*nd_dax), GFP_KERNEL);
  54         if (!nd_dax)
  55                 return NULL;
  56
  57         nd_pfn = &nd_dax->nd_pfn;
  58         nd_pfn->id = ida_simple_get(&nd_region->dax_ida, 0, 0, GFP_KERNEL);
  59         if (nd_pfn->id < 0) {
  60                 kfree(nd_dax);
  61                 return NULL;
  62         }
  63
  64         dev = &nd_pfn->dev;
  65         dev_set_name(dev, "dax%d.%d", nd_region->id, nd_pfn->id);
  66         dev->type = &nd_dax_device_type;
  67         dev->parent = &nd_region->dev;
  68
  69         return nd_dax;
  70 }
  71
  72 struct device *nd_dax_create(struct nd_region *nd_region)
  73 {
  74         struct device *dev = NULL;
  75         struct nd_dax *nd_dax;
  76
  77         if (!is_memory(&nd_region->dev))
  78                 return NULL;
  79
  80         nd_dax = nd_dax_alloc(nd_region);
  81         if (nd_dax)
  82                 dev = nd_pfn_devinit(&nd_dax->nd_pfn, NULL);
  83         nd_device_register(dev);
  84         return dev;
  85 }
  86
  87 int nd_dax_probe(struct device *dev, struct nd_namespace_common *ndns)
  88 {
  89         int rc;
  90         struct nd_dax *nd_dax;
  91         struct device *dax_dev;
  92         struct nd_pfn *nd_pfn;
  93         struct nd_pfn_sb *pfn_sb;
  94         struct nd_region *nd_region = to_nd_region(ndns->dev.parent);
  95
  96         if (ndns->force_raw)
  97                 return -ENODEV;
  98
  99         switch (ndns->claim_class) {
 100         case NVDIMM_CCLASS_NONE:
 101         case NVDIMM_CCLASS_DAX:
 102                 break;
 103         default:
 104                 return -ENODEV;
 105         }
 106
 107         nvdimm_bus_lock(&ndns->dev);
 108         nd_dax = nd_dax_alloc(nd_region);
 109         nd_pfn = &nd_dax->nd_pfn;
 110         dax_dev = nd_pfn_devinit(nd_pfn, ndns);
 111         nvdimm_bus_unlock(&ndns->dev);
 112         if (!dax_dev)
 113                 return -ENOMEM;
 114         pfn_sb = devm_kmalloc(dev, sizeof(*pfn_sb), GFP_KERNEL);
 115         nd_pfn->pfn_sb = pfn_sb;
 116         rc = nd_pfn_validate(nd_pfn, DAX_SIG);
 117         dev_dbg(dev, "dax: %s\n", rc == 0 ? dev_name(dax_dev) : "<none>");
 118         if (rc < 0) {
 119                 nd_detach_ndns(dax_dev, &nd_pfn->ndns);
 120                 put_device(dax_dev);
 121         } else
 122                 nd_device_register(dax_dev);
 123
 124         return rc;
 125 }
 126 EXPORT_SYMBOL(nd_dax_probe);