drivers/pci/hotplug/rpadlpar_sysfs.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Interface for Dynamic Logical Partitioning of I/O Slots on
   4  * RPA-compliant PPC64 platform.
   5  *
   6  * John Rose <johnrose@austin.ibm.com>
   7  * October 2003
   8  *
   9  * Copyright (C) 2003 IBM.
  10  */
  11 #include <linux/kobject.h>
  12 #include <linux/string.h>
  13 #include <linux/pci.h>
  14 #include <linux/pci_hotplug.h>
  15 #include "rpaphp.h"
  16 #include "rpadlpar.h"
  17 #include "../pci.h"
  18
  19 #define DLPAR_KOBJ_NAME       "control"
  20
  21 /* Those two have no quotes because they are passed to __ATTR() which
  22  * stringifies the argument (yuck !)
  23  */
  24 #define ADD_SLOT_ATTR_NAME    add_slot
  25 #define REMOVE_SLOT_ATTR_NAME remove_slot
  26
  27 static ssize_t add_slot_store(struct kobject *kobj, struct kobj_attribute *attr,
  28                               const char *buf, size_t nbytes)
  29 {
  30         char drc_name[MAX_DRC_NAME_LEN];
  31         char *end;
  32         int rc;
  33
  34         if (nbytes >= MAX_DRC_NAME_LEN)
  35                 return 0;
  36
  37         memcpy(drc_name, buf, nbytes);
  38
  39         end = strchr(drc_name, '\n');
  40         if (!end)
  41                 end = &drc_name[nbytes];
  42         *end = '\0';
  43
  44         rc = dlpar_add_slot(drc_name);
  45         if (rc)
  46                 return rc;
  47
  48         return nbytes;
  49 }
  50
  51 static ssize_t add_slot_show(struct kobject *kobj,
  52                              struct kobj_attribute *attr, char *buf)
  53 {
  54         return sprintf(buf, "0\n");
  55 }
  56
  57 static ssize_t remove_slot_store(struct kobject *kobj,
  58                                  struct kobj_attribute *attr,
  59                                  const char *buf, size_t nbytes)
  60 {
  61         char drc_name[MAX_DRC_NAME_LEN];
  62         int rc;
  63         char *end;
  64
  65         if (nbytes >= MAX_DRC_NAME_LEN)
  66                 return 0;
  67
  68         memcpy(drc_name, buf, nbytes);
  69
  70         end = strchr(drc_name, '\n');
  71         if (!end)
  72                 end = &drc_name[nbytes];
  73         *end = '\0';
  74
  75         rc = dlpar_remove_slot(drc_name);
  76         if (rc)
  77                 return rc;
  78
  79         return nbytes;
  80 }
  81
  82 static ssize_t remove_slot_show(struct kobject *kobj,
  83                                 struct kobj_attribute *attr, char *buf)
  84 {
  85         return sprintf(buf, "0\n");
  86 }
  87
  88 static struct kobj_attribute add_slot_attr =
  89         __ATTR(ADD_SLOT_ATTR_NAME, 0644, add_slot_show, add_slot_store);
  90
  91 static struct kobj_attribute remove_slot_attr =
  92         __ATTR(REMOVE_SLOT_ATTR_NAME, 0644, remove_slot_show, remove_slot_store);
  93
  94 static struct attribute *default_attrs[] = {
  95         &add_slot_attr.attr,
  96         &remove_slot_attr.attr,
  97         NULL,
  98 };
  99
 100 static const struct attribute_group dlpar_attr_group = {
 101         .attrs = default_attrs,
 102 };
 103
 104 static struct kobject *dlpar_kobj;
 105
 106 int dlpar_sysfs_init(void)
 107 {
 108         int error;
 109
 110         dlpar_kobj = kobject_create_and_add(DLPAR_KOBJ_NAME,
 111                                             &pci_slots_kset->kobj);
 112         if (!dlpar_kobj)
 113                 return -EINVAL;
 114
 115         error = sysfs_create_group(dlpar_kobj, &dlpar_attr_group);
 116         if (error)
 117                 kobject_put(dlpar_kobj);
 118         return error;
 119 }
 120
 121 void dlpar_sysfs_exit(void)
 122 {
 123         sysfs_remove_group(dlpar_kobj, &dlpar_attr_group);
 124         kobject_put(dlpar_kobj);
 125 }