drivers/s390/crypto/zcrypt_card.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  *  zcrypt 2.1.0
   4  *
   5  *  Copyright IBM Corp. 2001, 2012
   6  *  Author(s): Robert Burroughs
   7  *             Eric Rossman (edrossma@us.ibm.com)
   8  *             Cornelia Huck <cornelia.huck@de.ibm.com>
   9  *
  10  *  Hotplug & misc device support: Jochen Roehrig (roehrig@de.ibm.com)
  11  *  Major cleanup & driver split: Martin Schwidefsky <schwidefsky@de.ibm.com>
  12  *                                Ralph Wuerthner <rwuerthn@de.ibm.com>
  13  *  MSGTYPE restruct:             Holger Dengler <hd@linux.vnet.ibm.com>
  14  */
  15
  16 #include <linux/module.h>
  17 #include <linux/init.h>
  18 #include <linux/interrupt.h>
  19 #include <linux/miscdevice.h>
  20 #include <linux/fs.h>
  21 #include <linux/proc_fs.h>
  22 #include <linux/seq_file.h>
  23 #include <linux/compat.h>
  24 #include <linux/slab.h>
  25 #include <linux/atomic.h>
  26 #include <linux/uaccess.h>
  27 #include <linux/hw_random.h>
  28 #include <linux/debugfs.h>
  29 #include <asm/debug.h>
  30
  31 #include "zcrypt_debug.h"
  32 #include "zcrypt_api.h"
  33
  34 #include "zcrypt_msgtype6.h"
  35 #include "zcrypt_msgtype50.h"
  36
  37 /*
  38  * Device attributes common for all crypto card devices.
  39  */
  40
  41 static ssize_t type_show(struct device *dev,
  42                          struct device_attribute *attr, char *buf)
  43 {
  44         struct zcrypt_card *zc = to_ap_card(dev)->private;
  45
  46         return snprintf(buf, PAGE_SIZE, "%s\n", zc->type_string);
  47 }
  48
  49 static DEVICE_ATTR_RO(type);
  50
  51 static ssize_t online_show(struct device *dev,
  52                            struct device_attribute *attr,
  53                            char *buf)
  54 {
  55         struct zcrypt_card *zc = to_ap_card(dev)->private;
  56
  57         return snprintf(buf, PAGE_SIZE, "%d\n", zc->online);
  58 }
  59
  60 static ssize_t online_store(struct device *dev,
  61                             struct device_attribute *attr,
  62                             const char *buf, size_t count)
  63 {
  64         struct zcrypt_card *zc = to_ap_card(dev)->private;
  65         struct zcrypt_queue *zq;
  66         int online, id;
  67
  68         if (sscanf(buf, "%d\n", &online) != 1 || online < 0 || online > 1)
  69                 return -EINVAL;
  70
  71         zc->online = online;
  72         id = zc->card->id;
  73
  74         ZCRYPT_DBF(DBF_INFO, "card=%02x online=%d\n", id, online);
  75
  76         spin_lock(&zcrypt_list_lock);
  77         list_for_each_entry(zq, &zc->zqueues, list)
  78                 zcrypt_queue_force_online(zq, online);
  79         spin_unlock(&zcrypt_list_lock);
  80         return count;
  81 }
  82
  83 static DEVICE_ATTR_RW(online);
  84
  85 static ssize_t load_show(struct device *dev,
  86                          struct device_attribute *attr,
  87                          char *buf)
  88 {
  89         struct zcrypt_card *zc = to_ap_card(dev)->private;
  90
  91         return snprintf(buf, PAGE_SIZE, "%d\n", atomic_read(&zc->load));
  92 }
  93
  94 static DEVICE_ATTR_RO(load);
  95
  96 static struct attribute *zcrypt_card_attrs[] = {
  97         &dev_attr_type.attr,
  98         &dev_attr_online.attr,
  99         &dev_attr_load.attr,
 100         NULL,
 101 };
 102
 103 static const struct attribute_group zcrypt_card_attr_group = {
 104         .attrs = zcrypt_card_attrs,
 105 };
 106
 107 struct zcrypt_card *zcrypt_card_alloc(void)
 108 {
 109         struct zcrypt_card *zc;
 110
 111         zc = kzalloc(sizeof(struct zcrypt_card), GFP_KERNEL);
 112         if (!zc)
 113                 return NULL;
 114         INIT_LIST_HEAD(&zc->list);
 115         INIT_LIST_HEAD(&zc->zqueues);
 116         kref_init(&zc->refcount);
 117         return zc;
 118 }
 119 EXPORT_SYMBOL(zcrypt_card_alloc);
 120
 121 void zcrypt_card_free(struct zcrypt_card *zc)
 122 {
 123         kfree(zc);
 124 }
 125 EXPORT_SYMBOL(zcrypt_card_free);
 126
 127 static void zcrypt_card_release(struct kref *kref)
 128 {
 129         struct zcrypt_card *zdev =
 130                 container_of(kref, struct zcrypt_card, refcount);
 131         zcrypt_card_free(zdev);
 132 }
 133
 134 void zcrypt_card_get(struct zcrypt_card *zc)
 135 {
 136         kref_get(&zc->refcount);
 137 }
 138 EXPORT_SYMBOL(zcrypt_card_get);
 139
 140 int zcrypt_card_put(struct zcrypt_card *zc)
 141 {
 142         return kref_put(&zc->refcount, zcrypt_card_release);
 143 }
 144 EXPORT_SYMBOL(zcrypt_card_put);
 145
 146 /**
 147  * zcrypt_card_register() - Register a crypto card device.
 148  * @zc: Pointer to a crypto card device
 149  *
 150  * Register a crypto card device. Returns 0 if successful.
 151  */
 152 int zcrypt_card_register(struct zcrypt_card *zc)
 153 {
 154         int rc;
 155
 156         rc = sysfs_create_group(&zc->card->ap_dev.device.kobj,
 157                                 &zcrypt_card_attr_group);
 158         if (rc)
 159                 return rc;
 160
 161         spin_lock(&zcrypt_list_lock);
 162         list_add_tail(&zc->list, &zcrypt_card_list);
 163         spin_unlock(&zcrypt_list_lock);
 164
 165         zc->online = 1;
 166
 167         ZCRYPT_DBF(DBF_INFO, "card=%02x register online=1\n", zc->card->id);
 168
 169         return rc;
 170 }
 171 EXPORT_SYMBOL(zcrypt_card_register);
 172
 173 /**
 174  * zcrypt_card_unregister(): Unregister a crypto card device.
 175  * @zc: Pointer to crypto card device
 176  *
 177  * Unregister a crypto card device.
 178  */
 179 void zcrypt_card_unregister(struct zcrypt_card *zc)
 180 {
 181         ZCRYPT_DBF(DBF_INFO, "card=%02x unregister\n", zc->card->id);
 182
 183         spin_lock(&zcrypt_list_lock);
 184         list_del_init(&zc->list);
 185         spin_unlock(&zcrypt_list_lock);
 186         sysfs_remove_group(&zc->card->ap_dev.device.kobj,
 187                            &zcrypt_card_attr_group);
 188 }
 189 EXPORT_SYMBOL(zcrypt_card_unregister);