drivers/s390/crypto/zcrypt_card.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  *  Copyright IBM Corp. 2001, 2012
   4  *  Author(s): Robert Burroughs
   5  *             Eric Rossman (edrossma@us.ibm.com)
   6  *             Cornelia Huck <cornelia.huck@de.ibm.com>
   7  *
   8  *  Hotplug & misc device support: Jochen Roehrig (roehrig@de.ibm.com)
   9  *  Major cleanup & driver split: Martin Schwidefsky <schwidefsky@de.ibm.com>
  10  *                                Ralph Wuerthner <rwuerthn@de.ibm.com>
  11  *  MSGTYPE restruct:             Holger Dengler <hd@linux.vnet.ibm.com>
  12  */
  13
  14 #include <linux/module.h>
  15 #include <linux/init.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/miscdevice.h>
  18 #include <linux/fs.h>
  19 #include <linux/proc_fs.h>
  20 #include <linux/seq_file.h>
  21 #include <linux/compat.h>
  22 #include <linux/slab.h>
  23 #include <linux/atomic.h>
  24 #include <linux/uaccess.h>
  25 #include <linux/hw_random.h>
  26 #include <linux/debugfs.h>
  27 #include <asm/debug.h>
  28
  29 #include "zcrypt_debug.h"
  30 #include "zcrypt_api.h"
  31
  32 #include "zcrypt_msgtype6.h"
  33 #include "zcrypt_msgtype50.h"
  34
  35 /*
  36  * Device attributes common for all crypto card devices.
  37  */
  38
  39 static ssize_t type_show(struct device *dev,
  40                          struct device_attribute *attr, char *buf)
  41 {
  42         struct zcrypt_card *zc = to_ap_card(dev)->private;
  43
  44         return scnprintf(buf, PAGE_SIZE, "%s\n", zc->type_string);
  45 }
  46
  47 static DEVICE_ATTR_RO(type);
  48
  49 static ssize_t online_show(struct device *dev,
  50                            struct device_attribute *attr,
  51                            char *buf)
  52 {
  53         struct ap_card *ac = to_ap_card(dev);
  54         struct zcrypt_card *zc = ac->private;
  55         int online = ac->config && zc->online ? 1 : 0;
  56
  57         return scnprintf(buf, PAGE_SIZE, "%d\n", 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 ap_card *ac = to_ap_card(dev);
  65         struct zcrypt_card *zc = ac->private;
  66         struct zcrypt_queue *zq;
  67         int online, id;
  68
  69         if (sscanf(buf, "%d\n", &online) != 1 || online < 0 || online > 1)
  70                 return -EINVAL;
  71
  72         if (online && !ac->config)
  73                 return -ENODEV;
  74
  75         zc->online = online;
  76         id = zc->card->id;
  77
  78         ZCRYPT_DBF(DBF_INFO, "card=%02x online=%d\n", id, online);
  79
  80         spin_lock(&zcrypt_list_lock);
  81         list_for_each_entry(zq, &zc->zqueues, list)
  82                 zcrypt_queue_force_online(zq, online);
  83         spin_unlock(&zcrypt_list_lock);
  84         return count;
  85 }
  86
  87 static DEVICE_ATTR_RW(online);
  88
  89 static ssize_t load_show(struct device *dev,
  90                          struct device_attribute *attr,
  91                          char *buf)
  92 {
  93         struct zcrypt_card *zc = to_ap_card(dev)->private;
  94
  95         return scnprintf(buf, PAGE_SIZE, "%d\n", atomic_read(&zc->load));
  96 }
  97
  98 static DEVICE_ATTR_RO(load);
  99
 100 static struct attribute *zcrypt_card_attrs[] = {
 101         &dev_attr_type.attr,
 102         &dev_attr_online.attr,
 103         &dev_attr_load.attr,
 104         NULL,
 105 };
 106
 107 static const struct attribute_group zcrypt_card_attr_group = {
 108         .attrs = zcrypt_card_attrs,
 109 };
 110
 111 struct zcrypt_card *zcrypt_card_alloc(void)
 112 {
 113         struct zcrypt_card *zc;
 114
 115         zc = kzalloc(sizeof(struct zcrypt_card), GFP_KERNEL);
 116         if (!zc)
 117                 return NULL;
 118         INIT_LIST_HEAD(&zc->list);
 119         INIT_LIST_HEAD(&zc->zqueues);
 120         kref_init(&zc->refcount);
 121         return zc;
 122 }
 123 EXPORT_SYMBOL(zcrypt_card_alloc);
 124
 125 void zcrypt_card_free(struct zcrypt_card *zc)
 126 {
 127         kfree(zc);
 128 }
 129 EXPORT_SYMBOL(zcrypt_card_free);
 130
 131 static void zcrypt_card_release(struct kref *kref)
 132 {
 133         struct zcrypt_card *zdev =
 134                 container_of(kref, struct zcrypt_card, refcount);
 135         zcrypt_card_free(zdev);
 136 }
 137
 138 void zcrypt_card_get(struct zcrypt_card *zc)
 139 {
 140         kref_get(&zc->refcount);
 141 }
 142 EXPORT_SYMBOL(zcrypt_card_get);
 143
 144 int zcrypt_card_put(struct zcrypt_card *zc)
 145 {
 146         return kref_put(&zc->refcount, zcrypt_card_release);
 147 }
 148 EXPORT_SYMBOL(zcrypt_card_put);
 149
 150 /**
 151  * zcrypt_card_register() - Register a crypto card device.
 152  * @zc: Pointer to a crypto card device
 153  *
 154  * Register a crypto card device. Returns 0 if successful.
 155  */
 156 int zcrypt_card_register(struct zcrypt_card *zc)
 157 {
 158         int rc;
 159
 160         rc = sysfs_create_group(&zc->card->ap_dev.device.kobj,
 161                                 &zcrypt_card_attr_group);
 162         if (rc)
 163                 return rc;
 164
 165         spin_lock(&zcrypt_list_lock);
 166         list_add_tail(&zc->list, &zcrypt_card_list);
 167         spin_unlock(&zcrypt_list_lock);
 168
 169         zc->online = 1;
 170
 171         ZCRYPT_DBF(DBF_INFO, "card=%02x register online=1\n", zc->card->id);
 172
 173         return rc;
 174 }
 175 EXPORT_SYMBOL(zcrypt_card_register);
 176
 177 /**
 178  * zcrypt_card_unregister(): Unregister a crypto card device.
 179  * @zc: Pointer to crypto card device
 180  *
 181  * Unregister a crypto card device.
 182  */
 183 void zcrypt_card_unregister(struct zcrypt_card *zc)
 184 {
 185         ZCRYPT_DBF(DBF_INFO, "card=%02x unregister\n", zc->card->id);
 186
 187         spin_lock(&zcrypt_list_lock);
 188         list_del_init(&zc->list);
 189         spin_unlock(&zcrypt_list_lock);
 190         sysfs_remove_group(&zc->card->ap_dev.device.kobj,
 191                            &zcrypt_card_attr_group);
 192 }
 193 EXPORT_SYMBOL(zcrypt_card_unregister);