drivers/s390/crypto/zcrypt_queue.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 queue devices.
  39  */
  40
  41 static ssize_t zcrypt_queue_online_show(struct device *dev,
  42                                         struct device_attribute *attr,
  43                                         char *buf)
  44 {
  45         struct zcrypt_queue *zq = to_ap_queue(dev)->private;
  46
  47         return snprintf(buf, PAGE_SIZE, "%d\n", zq->online);
  48 }
  49
  50 static ssize_t zcrypt_queue_online_store(struct device *dev,
  51                                          struct device_attribute *attr,
  52                                          const char *buf, size_t count)
  53 {
  54         struct zcrypt_queue *zq = to_ap_queue(dev)->private;
  55         struct zcrypt_card *zc = zq->zcard;
  56         int online;
  57
  58         if (sscanf(buf, "%d\n", &online) != 1 || online < 0 || online > 1)
  59                 return -EINVAL;
  60
  61         if (online && !zc->online)
  62                 return -EINVAL;
  63         zq->online = online;
  64
  65         ZCRYPT_DBF(DBF_INFO, "queue=%02x.%04x online=%d\n",
  66                    AP_QID_CARD(zq->queue->qid),
  67                    AP_QID_QUEUE(zq->queue->qid),
  68                    online);
  69
  70         if (!online)
  71                 ap_flush_queue(zq->queue);
  72         return count;
  73 }
  74
  75 static DEVICE_ATTR(online, 0644, zcrypt_queue_online_show,
  76                    zcrypt_queue_online_store);
  77
  78 static struct attribute *zcrypt_queue_attrs[] = {
  79         &dev_attr_online.attr,
  80         NULL,
  81 };
  82
  83 static const struct attribute_group zcrypt_queue_attr_group = {
  84         .attrs = zcrypt_queue_attrs,
  85 };
  86
  87 void zcrypt_queue_force_online(struct zcrypt_queue *zq, int online)
  88 {
  89         zq->online = online;
  90         if (!online)
  91                 ap_flush_queue(zq->queue);
  92 }
  93
  94 struct zcrypt_queue *zcrypt_queue_alloc(size_t max_response_size)
  95 {
  96         struct zcrypt_queue *zq;
  97
  98         zq = kzalloc(sizeof(struct zcrypt_queue), GFP_KERNEL);
  99         if (!zq)
 100                 return NULL;
 101         zq->reply.message = kmalloc(max_response_size, GFP_KERNEL);
 102         if (!zq->reply.message)
 103                 goto out_free;
 104         zq->reply.length = max_response_size;
 105         INIT_LIST_HEAD(&zq->list);
 106         kref_init(&zq->refcount);
 107         return zq;
 108
 109 out_free:
 110         kfree(zq);
 111         return NULL;
 112 }
 113 EXPORT_SYMBOL(zcrypt_queue_alloc);
 114
 115 void zcrypt_queue_free(struct zcrypt_queue *zq)
 116 {
 117         kfree(zq->reply.message);
 118         kfree(zq);
 119 }
 120 EXPORT_SYMBOL(zcrypt_queue_free);
 121
 122 static void zcrypt_queue_release(struct kref *kref)
 123 {
 124         struct zcrypt_queue *zq =
 125                 container_of(kref, struct zcrypt_queue, refcount);
 126         zcrypt_queue_free(zq);
 127 }
 128
 129 void zcrypt_queue_get(struct zcrypt_queue *zq)
 130 {
 131         kref_get(&zq->refcount);
 132 }
 133 EXPORT_SYMBOL(zcrypt_queue_get);
 134
 135 int zcrypt_queue_put(struct zcrypt_queue *zq)
 136 {
 137         return kref_put(&zq->refcount, zcrypt_queue_release);
 138 }
 139 EXPORT_SYMBOL(zcrypt_queue_put);
 140
 141 /**
 142  * zcrypt_queue_register() - Register a crypto queue device.
 143  * @zq: Pointer to a crypto queue device
 144  *
 145  * Register a crypto queue device. Returns 0 if successful.
 146  */
 147 int zcrypt_queue_register(struct zcrypt_queue *zq)
 148 {
 149         struct zcrypt_card *zc;
 150         int rc;
 151
 152         spin_lock(&zcrypt_list_lock);
 153         zc = zq->queue->card->private;
 154         zcrypt_card_get(zc);
 155         zq->zcard = zc;
 156         zq->online = 1; /* New devices are online by default. */
 157
 158         ZCRYPT_DBF(DBF_INFO, "queue=%02x.%04x register online=1\n",
 159                    AP_QID_CARD(zq->queue->qid), AP_QID_QUEUE(zq->queue->qid));
 160
 161         list_add_tail(&zq->list, &zc->zqueues);
 162         zcrypt_device_count++;
 163         spin_unlock(&zcrypt_list_lock);
 164
 165         rc = sysfs_create_group(&zq->queue->ap_dev.device.kobj,
 166                                 &zcrypt_queue_attr_group);
 167         if (rc)
 168                 goto out;
 169         get_device(&zq->queue->ap_dev.device);
 170
 171         if (zq->ops->rng) {
 172                 rc = zcrypt_rng_device_add();
 173                 if (rc)
 174                         goto out_unregister;
 175         }
 176         return 0;
 177
 178 out_unregister:
 179         sysfs_remove_group(&zq->queue->ap_dev.device.kobj,
 180                            &zcrypt_queue_attr_group);
 181         put_device(&zq->queue->ap_dev.device);
 182 out:
 183         spin_lock(&zcrypt_list_lock);
 184         list_del_init(&zq->list);
 185         spin_unlock(&zcrypt_list_lock);
 186         zcrypt_card_put(zc);
 187         return rc;
 188 }
 189 EXPORT_SYMBOL(zcrypt_queue_register);
 190
 191 /**
 192  * zcrypt_queue_unregister(): Unregister a crypto queue device.
 193  * @zq: Pointer to crypto queue device
 194  *
 195  * Unregister a crypto queue device.
 196  */
 197 void zcrypt_queue_unregister(struct zcrypt_queue *zq)
 198 {
 199         struct zcrypt_card *zc;
 200
 201         ZCRYPT_DBF(DBF_INFO, "queue=%02x.%04x unregister\n",
 202                    AP_QID_CARD(zq->queue->qid), AP_QID_QUEUE(zq->queue->qid));
 203
 204         zc = zq->zcard;
 205         spin_lock(&zcrypt_list_lock);
 206         list_del_init(&zq->list);
 207         zcrypt_device_count--;
 208         spin_unlock(&zcrypt_list_lock);
 209         zcrypt_card_put(zc);
 210         if (zq->ops->rng)
 211                 zcrypt_rng_device_remove();
 212         sysfs_remove_group(&zq->queue->ap_dev.device.kobj,
 213                            &zcrypt_queue_attr_group);
 214         put_device(&zq->queue->ap_dev.device);
 215         zcrypt_queue_put(zq);
 216 }
 217 EXPORT_SYMBOL(zcrypt_queue_unregister);