LXR linux/drivers/nvdimm/dax

   1/*
   2 * Copyright(c) 2013-2016 Intel Corporation. All rights reserved.
   3 *
   4 * This program is free software; you can redistribute it and/or modify
   5 * it under the terms of version 2 of the GNU General Public License as
   6 * published by the Free Software Foundation.
   7 *
   8 * This program is distributed in the hope that it will be useful, but
   9 * WITHOUT ANY WARRANTY; without even the implied warranty of
  10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11 * General Public License for more details.
  12 */
  13#include <linux/device.h>
  14#include <linux/sizes.h>
  15#include <linux/slab.h>
  16#include <linux/mm.h>
  17#include "nd-core.h"
  18#include "pfn.h"
  19#include "nd.h"
  20
  21static void nd_dax_release(struct device *dev)
  22{
  23        struct nd_region *nd_region = to_nd_region(dev->parent);
  24        struct nd_dax *nd_dax = to_nd_dax(dev);
  25        struct nd_pfn *nd_pfn = &nd_dax->nd_pfn;
  26
  27        dev_dbg(dev, "%s\n", __func__);
  28        nd_detach_ndns(dev, &nd_pfn->ndns);
  29        ida_simple_remove(&nd_region->dax_ida, nd_pfn->id);
  30        kfree(nd_pfn->uuid);
  31        kfree(nd_dax);
  32}
  33
  34static struct device_type nd_dax_device_type = {
  35        .name = "nd_dax",
  36        .release = nd_dax_release,
  37};
  38
  39bool is_nd_dax(struct device *dev)
  40{
  41        return dev ? dev->type == &nd_dax_device_type : false;
  42}
  43EXPORT_SYMBOL(is_nd_dax);
  44
  45struct nd_dax *to_nd_dax(struct device *dev)
  46{
  47        struct nd_dax *nd_dax = container_of(dev, struct nd_dax, nd_pfn.dev);
  48
  49        WARN_ON(!is_nd_dax(dev));
  50        return nd_dax;
  51}
  52EXPORT_SYMBOL(to_nd_dax);
  53
  54static const struct attribute_group *nd_dax_attribute_groups[] = {
  55        &nd_pfn_attribute_group,
  56        &nd_device_attribute_group,
  57        &nd_numa_attribute_group,
  58        NULL,
  59};
  60
  61static struct nd_dax *nd_dax_alloc(struct nd_region *nd_region)
  62{
  63        struct nd_pfn *nd_pfn;
  64        struct nd_dax *nd_dax;
  65        struct device *dev;
  66
  67        nd_dax = kzalloc(sizeof(*nd_dax), GFP_KERNEL);
  68        if (!nd_dax)
  69                return NULL;
  70
  71        nd_pfn = &nd_dax->nd_pfn;
  72        nd_pfn->id = ida_simple_get(&nd_region->dax_ida, 0, 0, GFP_KERNEL);
  73        if (nd_pfn->id < 0) {
  74                kfree(nd_dax);
  75                return NULL;
  76        }
  77
  78        dev = &nd_pfn->dev;
  79        dev_set_name(dev, "dax%d.%d", nd_region->id, nd_pfn->id);
  80        dev->groups = nd_dax_attribute_groups;
  81        dev->type = &nd_dax_device_type;
  82        dev->parent = &nd_region->dev;
  83
  84        return nd_dax;
  85}
  86
  87struct device *nd_dax_create(struct nd_region *nd_region)
  88{
  89        struct device *dev = NULL;
  90        struct nd_dax *nd_dax;
  91
  92        if (!is_memory(&nd_region->dev))
  93                return NULL;
  94
  95        nd_dax = nd_dax_alloc(nd_region);
  96        if (nd_dax)
  97                dev = nd_pfn_devinit(&nd_dax->nd_pfn, NULL);
  98        __nd_device_register(dev);
  99        return dev;
 100}
 101
 102int nd_dax_probe(struct device *dev, struct nd_namespace_common *ndns)
 103{
 104        int rc;
 105        struct nd_dax *nd_dax;
 106        struct device *dax_dev;
 107        struct nd_pfn *nd_pfn;
 108        struct nd_pfn_sb *pfn_sb;
 109        struct nd_region *nd_region = to_nd_region(ndns->dev.parent);
 110
 111        if (ndns->force_raw)
 112                return -ENODEV;
 113
 114        switch (ndns->claim_class) {
 115        case NVDIMM_CCLASS_NONE:
 116        case NVDIMM_CCLASS_DAX:
 117                break;
 118        default:
 119                return -ENODEV;
 120        }
 121
 122        nvdimm_bus_lock(&ndns->dev);
 123        nd_dax = nd_dax_alloc(nd_region);
 124        nd_pfn = &nd_dax->nd_pfn;
 125        dax_dev = nd_pfn_devinit(nd_pfn, ndns);
 126        nvdimm_bus_unlock(&ndns->dev);
 127        if (!dax_dev)
 128                return -ENOMEM;
 129        pfn_sb = devm_kzalloc(dev, sizeof(*pfn_sb), GFP_KERNEL);
 130        nd_pfn->pfn_sb = pfn_sb;
 131        rc = nd_pfn_validate(nd_pfn, DAX_SIG);
 132        dev_dbg(dev, "%s: dax: %s\n", __func__,
 133                        rc == 0 ? dev_name(dax_dev) : "<none>");
 134        if (rc < 0) {
 135                nd_detach_ndns(dax_dev, &nd_pfn->ndns);
 136                put_device(dax_dev);
 137        } else
 138                __nd_device_register(dax_dev);
 139
 140        return rc;
 141}
 142EXPORT_SYMBOL(nd_dax_probe);
 143