drivers/s390/crypto/zcrypt_queue.c

   1 /*
   2  *  zcrypt 2.1.0
   3  *
   4  *  Copyright IBM Corp. 2001, 2012
   5  *  Author(s): Robert Burroughs
   6  *             Eric Rossman (edrossma@us.ibm.com)
   7  *             Cornelia Huck <cornelia.huck@de.ibm.com>
   8  *
   9  *  Hotplug & misc device support: Jochen Roehrig (roehrig@de.ibm.com)
  10  *  Major cleanup & driver split: Martin Schwidefsky <schwidefsky@de.ibm.com>
  11  *                                Ralph Wuerthner <rwuerthn@de.ibm.com>
  12  *  MSGTYPE restruct:             Holger Dengler <hd@linux.vnet.ibm.com>
  13  *
  14  * This program is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2, or (at your option)
  17  * any later version.
  18  *
  19  * This program is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  22  * GNU General Public License for more details.
  23  */
  24
  25 #include <linux/module.h>
  26 #include <linux/init.h>
  27 #include <linux/interrupt.h>
  28 #include <linux/miscdevice.h>
  29 #include <linux/fs.h>
  30 #include <linux/proc_fs.h>
  31 #include <linux/seq_file.h>
  32 #include <linux/compat.h>
  33 #include <linux/slab.h>
  34 #include <linux/atomic.h>
  35 #include <linux/uaccess.h>
  36 #include <linux/hw_random.h>
  37 #include <linux/debugfs.h>
  38 #include <asm/debug.h>
  39
  40 #include "zcrypt_debug.h"
  41 #include "zcrypt_api.h"
  42
  43 #include "zcrypt_msgtype6.h"
  44 #include "zcrypt_msgtype50.h"
  45
  46 /*
  47  * Device attributes common for all crypto queue devices.
  48  */
  49
  50 static ssize_t zcrypt_queue_online_show(struct device *dev,
  51                                         struct device_attribute *attr,
  52                                         char *buf)
  53 {
  54         struct zcrypt_queue *zq = to_ap_queue(dev)->private;
  55
  56         return snprintf(buf, PAGE_SIZE, "%d\n", zq->online);
  57 }
  58
  59 static ssize_t zcrypt_queue_online_store(struct device *dev,
  60                                          struct device_attribute *attr,
  61                                          const char *buf, size_t count)
  62 {
  63         struct zcrypt_queue *zq = to_ap_queue(dev)->private;
  64         struct zcrypt_card *zc = zq->zcard;
  65         int online;
  66
  67         if (sscanf(buf, "%d\n", &online) != 1 || online < 0 || online > 1)
  68                 return -EINVAL;
  69
  70         if (online && !zc->online)
  71                 return -EINVAL;
  72         zq->online = online;
  73
  74         ZCRYPT_DBF(DBF_INFO, "queue=%02x.%04x online=%d\n",
  75                    AP_QID_CARD(zq->queue->qid),
  76                    AP_QID_QUEUE(zq->queue->qid),
  77                    online);
  78
  79         if (!online)
  80                 ap_flush_queue(zq->queue);
  81         return count;
  82 }
  83
  84 static DEVICE_ATTR(online, 0644, zcrypt_queue_online_show,
  85                    zcrypt_queue_online_store);
  86
  87 static struct attribute *zcrypt_queue_attrs[] = {
  88         &dev_attr_online.attr,
  89         NULL,
  90 };
  91
  92 static const struct attribute_group zcrypt_queue_attr_group = {
  93         .attrs = zcrypt_queue_attrs,
  94 };
  95
  96 void zcrypt_queue_force_online(struct zcrypt_queue *zq, int online)
  97 {
  98         zq->online = online;
  99         if (!online)
 100                 ap_flush_queue(zq->queue);
 101 }
 102
 103 struct zcrypt_queue *zcrypt_queue_alloc(size_t max_response_size)
 104 {
 105         struct zcrypt_queue *zq;
 106
 107         zq = kzalloc(sizeof(struct zcrypt_queue), GFP_KERNEL);
 108         if (!zq)
 109                 return NULL;
 110         zq->reply.message = kmalloc(max_response_size, GFP_KERNEL);
 111         if (!zq->reply.message)
 112                 goto out_free;
 113         zq->reply.length = max_response_size;
 114         INIT_LIST_HEAD(&zq->list);
 115         kref_init(&zq->refcount);
 116         return zq;
 117
 118 out_free:
 119         kfree(zq);
 120         return NULL;
 121 }
 122 EXPORT_SYMBOL(zcrypt_queue_alloc);
 123
 124 void zcrypt_queue_free(struct zcrypt_queue *zq)
 125 {
 126         kfree(zq->reply.message);
 127         kfree(zq);
 128 }
 129 EXPORT_SYMBOL(zcrypt_queue_free);
 130
 131 static void zcrypt_queue_release(struct kref *kref)
 132 {
 133         struct zcrypt_queue *zq =
 134                 container_of(kref, struct zcrypt_queue, refcount);
 135         zcrypt_queue_free(zq);
 136 }
 137
 138 void zcrypt_queue_get(struct zcrypt_queue *zq)
 139 {
 140         kref_get(&zq->refcount);
 141 }
 142 EXPORT_SYMBOL(zcrypt_queue_get);
 143
 144 int zcrypt_queue_put(struct zcrypt_queue *zq)
 145 {
 146         return kref_put(&zq->refcount, zcrypt_queue_release);
 147 }
 148 EXPORT_SYMBOL(zcrypt_queue_put);
 149
 150 /**
 151  * zcrypt_queue_register() - Register a crypto queue device.
 152  * @zq: Pointer to a crypto queue device
 153  *
 154  * Register a crypto queue device. Returns 0 if successful.
 155  */
 156 int zcrypt_queue_register(struct zcrypt_queue *zq)
 157 {
 158         struct zcrypt_card *zc;
 159         int rc;
 160
 161         spin_lock(&zcrypt_list_lock);
 162         zc = zq->queue->card->private;
 163         zcrypt_card_get(zc);
 164         zq->zcard = zc;
 165         zq->online = 1; /* New devices are online by default. */
 166
 167         ZCRYPT_DBF(DBF_INFO, "queue=%02x.%04x register online=1\n",
 168                    AP_QID_CARD(zq->queue->qid), AP_QID_QUEUE(zq->queue->qid));
 169
 170         list_add_tail(&zq->list, &zc->zqueues);
 171         zcrypt_device_count++;
 172         spin_unlock(&zcrypt_list_lock);
 173
 174         rc = sysfs_create_group(&zq->queue->ap_dev.device.kobj,
 175                                 &zcrypt_queue_attr_group);
 176         if (rc)
 177                 goto out;
 178         get_device(&zq->queue->ap_dev.device);
 179
 180         if (zq->ops->rng) {
 181                 rc = zcrypt_rng_device_add();
 182                 if (rc)
 183                         goto out_unregister;
 184         }
 185         return 0;
 186
 187 out_unregister:
 188         sysfs_remove_group(&zq->queue->ap_dev.device.kobj,
 189                            &zcrypt_queue_attr_group);
 190         put_device(&zq->queue->ap_dev.device);
 191 out:
 192         spin_lock(&zcrypt_list_lock);
 193         list_del_init(&zq->list);
 194         spin_unlock(&zcrypt_list_lock);
 195         zcrypt_card_put(zc);
 196         return rc;
 197 }
 198 EXPORT_SYMBOL(zcrypt_queue_register);
 199
 200 /**
 201  * zcrypt_queue_unregister(): Unregister a crypto queue device.
 202  * @zq: Pointer to crypto queue device
 203  *
 204  * Unregister a crypto queue device.
 205  */
 206 void zcrypt_queue_unregister(struct zcrypt_queue *zq)
 207 {
 208         struct zcrypt_card *zc;
 209
 210         ZCRYPT_DBF(DBF_INFO, "queue=%02x.%04x unregister\n",
 211                    AP_QID_CARD(zq->queue->qid), AP_QID_QUEUE(zq->queue->qid));
 212
 213         zc = zq->zcard;
 214         spin_lock(&zcrypt_list_lock);
 215         list_del_init(&zq->list);
 216         zcrypt_device_count--;
 217         spin_unlock(&zcrypt_list_lock);
 218         zcrypt_card_put(zc);
 219         if (zq->ops->rng)
 220                 zcrypt_rng_device_remove();
 221         sysfs_remove_group(&zq->queue->ap_dev.device.kobj,
 222                            &zcrypt_queue_attr_group);
 223         put_device(&zq->queue->ap_dev.device);
 224         zcrypt_queue_put(zq);
 225 }
 226 EXPORT_SYMBOL(zcrypt_queue_unregister);