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 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 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_RW(online);
  76
  77 static ssize_t load_show(struct device *dev,
  78                          struct device_attribute *attr,
  79                          char *buf)
  80 {
  81         struct zcrypt_queue *zq = to_ap_queue(dev)->private;
  82
  83         return snprintf(buf, PAGE_SIZE, "%d\n", atomic_read(&zq->load));
  84 }
  85
  86 static DEVICE_ATTR_RO(load);
  87
  88 static struct attribute *zcrypt_queue_attrs[] = {
  89         &dev_attr_online.attr,
  90         &dev_attr_load.attr,
  91         NULL,
  92 };
  93
  94 static const struct attribute_group zcrypt_queue_attr_group = {
  95         .attrs = zcrypt_queue_attrs,
  96 };
  97
  98 void zcrypt_queue_force_online(struct zcrypt_queue *zq, int online)
  99 {
 100         zq->online = online;
 101         if (!online)
 102                 ap_flush_queue(zq->queue);
 103 }
 104
 105 struct zcrypt_queue *zcrypt_queue_alloc(size_t max_response_size)
 106 {
 107         struct zcrypt_queue *zq;
 108
 109         zq = kzalloc(sizeof(struct zcrypt_queue), GFP_KERNEL);
 110         if (!zq)
 111                 return NULL;
 112         zq->reply.message = kmalloc(max_response_size, GFP_KERNEL);
 113         if (!zq->reply.message)
 114                 goto out_free;
 115         zq->reply.length = max_response_size;
 116         INIT_LIST_HEAD(&zq->list);
 117         kref_init(&zq->refcount);
 118         return zq;
 119
 120 out_free:
 121         kfree(zq);
 122         return NULL;
 123 }
 124 EXPORT_SYMBOL(zcrypt_queue_alloc);
 125
 126 void zcrypt_queue_free(struct zcrypt_queue *zq)
 127 {
 128         kfree(zq->reply.message);
 129         kfree(zq);
 130 }
 131 EXPORT_SYMBOL(zcrypt_queue_free);
 132
 133 static void zcrypt_queue_release(struct kref *kref)
 134 {
 135         struct zcrypt_queue *zq =
 136                 container_of(kref, struct zcrypt_queue, refcount);
 137         zcrypt_queue_free(zq);
 138 }
 139
 140 void zcrypt_queue_get(struct zcrypt_queue *zq)
 141 {
 142         kref_get(&zq->refcount);
 143 }
 144 EXPORT_SYMBOL(zcrypt_queue_get);
 145
 146 int zcrypt_queue_put(struct zcrypt_queue *zq)
 147 {
 148         return kref_put(&zq->refcount, zcrypt_queue_release);
 149 }
 150 EXPORT_SYMBOL(zcrypt_queue_put);
 151
 152 /**
 153  * zcrypt_queue_register() - Register a crypto queue device.
 154  * @zq: Pointer to a crypto queue device
 155  *
 156  * Register a crypto queue device. Returns 0 if successful.
 157  */
 158 int zcrypt_queue_register(struct zcrypt_queue *zq)
 159 {
 160         struct zcrypt_card *zc;
 161         int rc;
 162
 163         spin_lock(&zcrypt_list_lock);
 164         zc = zq->queue->card->private;
 165         zcrypt_card_get(zc);
 166         zq->zcard = zc;
 167         zq->online = 1; /* New devices are online by default. */
 168
 169         ZCRYPT_DBF(DBF_INFO, "queue=%02x.%04x register online=1\n",
 170                    AP_QID_CARD(zq->queue->qid), AP_QID_QUEUE(zq->queue->qid));
 171
 172         list_add_tail(&zq->list, &zc->zqueues);
 173         zcrypt_device_count++;
 174         spin_unlock(&zcrypt_list_lock);
 175
 176         rc = sysfs_create_group(&zq->queue->ap_dev.device.kobj,
 177                                 &zcrypt_queue_attr_group);
 178         if (rc)
 179                 goto out;
 180         get_device(&zq->queue->ap_dev.device);
 181
 182         if (zq->ops->rng) {
 183                 rc = zcrypt_rng_device_add();
 184                 if (rc)
 185                         goto out_unregister;
 186         }
 187         return 0;
 188
 189 out_unregister:
 190         sysfs_remove_group(&zq->queue->ap_dev.device.kobj,
 191                            &zcrypt_queue_attr_group);
 192         put_device(&zq->queue->ap_dev.device);
 193 out:
 194         spin_lock(&zcrypt_list_lock);
 195         list_del_init(&zq->list);
 196         spin_unlock(&zcrypt_list_lock);
 197         zcrypt_card_put(zc);
 198         return rc;
 199 }
 200 EXPORT_SYMBOL(zcrypt_queue_register);
 201
 202 /**
 203  * zcrypt_queue_unregister(): Unregister a crypto queue device.
 204  * @zq: Pointer to crypto queue device
 205  *
 206  * Unregister a crypto queue device.
 207  */
 208 void zcrypt_queue_unregister(struct zcrypt_queue *zq)
 209 {
 210         struct zcrypt_card *zc;
 211
 212         ZCRYPT_DBF(DBF_INFO, "queue=%02x.%04x unregister\n",
 213                    AP_QID_CARD(zq->queue->qid), AP_QID_QUEUE(zq->queue->qid));
 214
 215         zc = zq->zcard;
 216         spin_lock(&zcrypt_list_lock);
 217         list_del_init(&zq->list);
 218         zcrypt_device_count--;
 219         spin_unlock(&zcrypt_list_lock);
 220         zcrypt_card_put(zc);
 221         if (zq->ops->rng)
 222                 zcrypt_rng_device_remove();
 223         sysfs_remove_group(&zq->queue->ap_dev.device.kobj,
 224                            &zcrypt_queue_attr_group);
 225         put_device(&zq->queue->ap_dev.device);
 226         zcrypt_queue_put(zq);
 227 }
 228 EXPORT_SYMBOL(zcrypt_queue_unregister);