drivers/nvdimm/bus.c

   1 /*
   2  * Copyright(c) 2013-2015 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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  14 #include <linux/uaccess.h>
  15 #include <linux/fcntl.h>
  16 #include <linux/slab.h>
  17 #include <linux/fs.h>
  18 #include <linux/io.h>
  19 #include "nd-core.h"
  20
  21 static int nvdimm_bus_major;
  22 static struct class *nd_class;
  23
  24 int nvdimm_bus_create_ndctl(struct nvdimm_bus *nvdimm_bus)
  25 {
  26         dev_t devt = MKDEV(nvdimm_bus_major, nvdimm_bus->id);
  27         struct device *dev;
  28
  29         dev = device_create(nd_class, &nvdimm_bus->dev, devt, nvdimm_bus,
  30                         "ndctl%d", nvdimm_bus->id);
  31
  32         if (IS_ERR(dev)) {
  33                 dev_dbg(&nvdimm_bus->dev, "failed to register ndctl%d: %ld\n",
  34                                 nvdimm_bus->id, PTR_ERR(dev));
  35                 return PTR_ERR(dev);
  36         }
  37         return 0;
  38 }
  39
  40 void nvdimm_bus_destroy_ndctl(struct nvdimm_bus *nvdimm_bus)
  41 {
  42         device_destroy(nd_class, MKDEV(nvdimm_bus_major, nvdimm_bus->id));
  43 }
  44
  45 static long nd_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
  46 {
  47         return -ENXIO;
  48 }
  49
  50 static const struct file_operations nvdimm_bus_fops = {
  51         .owner = THIS_MODULE,
  52         .open = nonseekable_open,
  53         .unlocked_ioctl = nd_ioctl,
  54         .compat_ioctl = nd_ioctl,
  55         .llseek = noop_llseek,
  56 };
  57
  58 int __init nvdimm_bus_init(void)
  59 {
  60         int rc;
  61
  62         rc = register_chrdev(0, "ndctl", &nvdimm_bus_fops);
  63         if (rc < 0)
  64                 return rc;
  65         nvdimm_bus_major = rc;
  66
  67         nd_class = class_create(THIS_MODULE, "nd");
  68         if (IS_ERR(nd_class))
  69                 goto err_class;
  70
  71         return 0;
  72
  73  err_class:
  74         unregister_chrdev(nvdimm_bus_major, "ndctl");
  75
  76         return rc;
  77 }
  78
  79 void __exit nvdimm_bus_exit(void)
  80 {
  81         class_destroy(nd_class);
  82         unregister_chrdev(nvdimm_bus_major, "ndctl");
  83 }