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 snprintf(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 zcrypt_card *zc = to_ap_card(dev)->private;
  54
  55         return snprintf(buf, PAGE_SIZE, "%d\n", zc->online);
  56 }
  57
  58 static ssize_t online_store(struct device *dev,
  59                             struct device_attribute *attr,
  60                             const char *buf, size_t count)
  61 {
  62         struct zcrypt_card *zc = to_ap_card(dev)->private;
  63         struct zcrypt_queue *zq;
  64         int online, id;
  65
  66         if (sscanf(buf, "%d\n", &online) != 1 || online < 0 || online > 1)
  67                 return -EINVAL;
  68
  69         zc->online = online;
  70         id = zc->card->id;
  71
  72         ZCRYPT_DBF(DBF_INFO, "card=%02x online=%d\n", id, online);
  73
  74         spin_lock(&zcrypt_list_lock);
  75         list_for_each_entry(zq, &zc->zqueues, list)
  76                 zcrypt_queue_force_online(zq, online);
  77         spin_unlock(&zcrypt_list_lock);
  78         return count;
  79 }
  80
  81 static DEVICE_ATTR_RW(online);
  82
  83 static ssize_t load_show(struct device *dev,
  84                          struct device_attribute *attr,
  85                          char *buf)
  86 {
  87         struct zcrypt_card *zc = to_ap_card(dev)->private;
  88
  89         return snprintf(buf, PAGE_SIZE, "%d\n", atomic_read(&zc->load));
  90 }
  91
  92 static DEVICE_ATTR_RO(load);
  93
  94 static struct attribute *zcrypt_card_attrs[] = {
  95         &dev_attr_type.attr,
  96         &dev_attr_online.attr,
  97         &dev_attr_load.attr,
  98         NULL,
  99 };
 100
 101 static const struct attribute_group zcrypt_card_attr_group = {
 102         .attrs = zcrypt_card_attrs,
 103 };
 104
 105 struct zcrypt_card *zcrypt_card_alloc(void)
 106 {
 107         struct zcrypt_card *zc;
 108
 109         zc = kzalloc(sizeof(struct zcrypt_card), GFP_KERNEL);
 110         if (!zc)
 111                 return NULL;
 112         INIT_LIST_HEAD(&zc->list);
 113         INIT_LIST_HEAD(&zc->zqueues);
 114         kref_init(&zc->refcount);
 115         return zc;
 116 }
 117 EXPORT_SYMBOL(zcrypt_card_alloc);
 118
 119 void zcrypt_card_free(struct zcrypt_card *zc)
 120 {
 121         kfree(zc);
 122 }
 123 EXPORT_SYMBOL(zcrypt_card_free);
 124
 125 static void zcrypt_card_release(struct kref *kref)
 126 {
 127         struct zcrypt_card *zdev =
 128                 container_of(kref, struct zcrypt_card, refcount);
 129         zcrypt_card_free(zdev);
 130 }
 131
 132 void zcrypt_card_get(struct zcrypt_card *zc)
 133 {
 134         kref_get(&zc->refcount);
 135 }
 136 EXPORT_SYMBOL(zcrypt_card_get);
 137
 138 int zcrypt_card_put(struct zcrypt_card *zc)
 139 {
 140         return kref_put(&zc->refcount, zcrypt_card_release);
 141 }
 142 EXPORT_SYMBOL(zcrypt_card_put);
 143
 144 /**
 145  * zcrypt_card_register() - Register a crypto card device.
 146  * @zc: Pointer to a crypto card device
 147  *
 148  * Register a crypto card device. Returns 0 if successful.
 149  */
 150 int zcrypt_card_register(struct zcrypt_card *zc)
 151 {
 152         int rc;
 153
 154         rc = sysfs_create_group(&zc->card->ap_dev.device.kobj,
 155                                 &zcrypt_card_attr_group);
 156         if (rc)
 157                 return rc;
 158
 159         spin_lock(&zcrypt_list_lock);
 160         list_add_tail(&zc->list, &zcrypt_card_list);
 161         spin_unlock(&zcrypt_list_lock);
 162
 163         zc->online = 1;
 164
 165         ZCRYPT_DBF(DBF_INFO, "card=%02x register online=1\n", zc->card->id);
 166
 167         return rc;
 168 }
 169 EXPORT_SYMBOL(zcrypt_card_register);
 170
 171 /**
 172  * zcrypt_card_unregister(): Unregister a crypto card device.
 173  * @zc: Pointer to crypto card device
 174  *
 175  * Unregister a crypto card device.
 176  */
 177 void zcrypt_card_unregister(struct zcrypt_card *zc)
 178 {
 179         ZCRYPT_DBF(DBF_INFO, "card=%02x unregister\n", zc->card->id);
 180
 181         spin_lock(&zcrypt_list_lock);
 182         list_del_init(&zc->list);
 183         spin_unlock(&zcrypt_list_lock);
 184         sysfs_remove_group(&zc->card->ap_dev.device.kobj,
 185                            &zcrypt_card_attr_group);
 186 }
 187 EXPORT_SYMBOL(zcrypt_card_unregister);