drivers/s390/crypto/zcrypt_queue.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 queue devices.
  37  */
  38
  39 static ssize_t online_show(struct device *dev,
  40                            struct device_attribute *attr,
  41                            char *buf)
  42 {
  43         struct ap_queue *aq = to_ap_queue(dev);
  44         struct zcrypt_queue *zq = aq->private;
  45         int online = aq->config && zq->online ? 1 : 0;
  46
  47         return scnprintf(buf, PAGE_SIZE, "%d\n", 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 ap_queue *aq = to_ap_queue(dev);
  55         struct zcrypt_queue *zq = aq->private;
  56         struct zcrypt_card *zc = zq->zcard;
  57         int online;
  58
  59         if (sscanf(buf, "%d\n", &online) != 1 || online < 0 || online > 1)
  60                 return -EINVAL;
  61
  62         if (online && (!aq->config || !aq->card->config))
  63                 return -ENODEV;
  64         if (online && !zc->online)
  65                 return -EINVAL;
  66         zq->online = online;
  67
  68         ZCRYPT_DBF(DBF_INFO, "queue=%02x.%04x online=%d\n",
  69                    AP_QID_CARD(zq->queue->qid),
  70                    AP_QID_QUEUE(zq->queue->qid),
  71                    online);
  72
  73         ap_send_online_uevent(&aq->ap_dev, online);
  74
  75         if (!online)
  76                 ap_flush_queue(zq->queue);
  77         return count;
  78 }
  79
  80 static DEVICE_ATTR_RW(online);
  81
  82 static ssize_t load_show(struct device *dev,
  83                          struct device_attribute *attr,
  84                          char *buf)
  85 {
  86         struct zcrypt_queue *zq = to_ap_queue(dev)->private;
  87
  88         return scnprintf(buf, PAGE_SIZE, "%d\n", atomic_read(&zq->load));
  89 }
  90
  91 static DEVICE_ATTR_RO(load);
  92
  93 static struct attribute *zcrypt_queue_attrs[] = {
  94         &dev_attr_online.attr,
  95         &dev_attr_load.attr,
  96         NULL,
  97 };
  98
  99 static const struct attribute_group zcrypt_queue_attr_group = {
 100         .attrs = zcrypt_queue_attrs,
 101 };
 102
 103 bool zcrypt_queue_force_online(struct zcrypt_queue *zq, int online)
 104 {
 105         if (!!zq->online != !!online) {
 106                 zq->online = online;
 107                 if (!online)
 108                         ap_flush_queue(zq->queue);
 109                 return true;
 110         }
 111         return false;
 112 }
 113
 114 struct zcrypt_queue *zcrypt_queue_alloc(size_t max_response_size)
 115 {
 116         struct zcrypt_queue *zq;
 117
 118         zq = kzalloc(sizeof(struct zcrypt_queue), GFP_KERNEL);
 119         if (!zq)
 120                 return NULL;
 121         zq->reply.msg = kmalloc(max_response_size, GFP_KERNEL);
 122         if (!zq->reply.msg)
 123                 goto out_free;
 124         zq->reply.len = max_response_size;
 125         INIT_LIST_HEAD(&zq->list);
 126         kref_init(&zq->refcount);
 127         return zq;
 128
 129 out_free:
 130         kfree(zq);
 131         return NULL;
 132 }
 133 EXPORT_SYMBOL(zcrypt_queue_alloc);
 134
 135 void zcrypt_queue_free(struct zcrypt_queue *zq)
 136 {
 137         kfree(zq->reply.msg);
 138         kfree(zq);
 139 }
 140 EXPORT_SYMBOL(zcrypt_queue_free);
 141
 142 static void zcrypt_queue_release(struct kref *kref)
 143 {
 144         struct zcrypt_queue *zq =
 145                 container_of(kref, struct zcrypt_queue, refcount);
 146         zcrypt_queue_free(zq);
 147 }
 148
 149 void zcrypt_queue_get(struct zcrypt_queue *zq)
 150 {
 151         kref_get(&zq->refcount);
 152 }
 153 EXPORT_SYMBOL(zcrypt_queue_get);
 154
 155 int zcrypt_queue_put(struct zcrypt_queue *zq)
 156 {
 157         return kref_put(&zq->refcount, zcrypt_queue_release);
 158 }
 159 EXPORT_SYMBOL(zcrypt_queue_put);
 160
 161 /**
 162  * zcrypt_queue_register() - Register a crypto queue device.
 163  * @zq: Pointer to a crypto queue device
 164  *
 165  * Register a crypto queue device. Returns 0 if successful.
 166  */
 167 int zcrypt_queue_register(struct zcrypt_queue *zq)
 168 {
 169         struct zcrypt_card *zc;
 170         int rc;
 171
 172         spin_lock(&zcrypt_list_lock);
 173         zc = zq->queue->card->private;
 174         zcrypt_card_get(zc);
 175         zq->zcard = zc;
 176         zq->online = 1; /* New devices are online by default. */
 177
 178         ZCRYPT_DBF(DBF_INFO, "queue=%02x.%04x register online=1\n",
 179                    AP_QID_CARD(zq->queue->qid), AP_QID_QUEUE(zq->queue->qid));
 180
 181         list_add_tail(&zq->list, &zc->zqueues);
 182         spin_unlock(&zcrypt_list_lock);
 183
 184         rc = sysfs_create_group(&zq->queue->ap_dev.device.kobj,
 185                                 &zcrypt_queue_attr_group);
 186         if (rc)
 187                 goto out;
 188
 189         if (zq->ops->rng) {
 190                 rc = zcrypt_rng_device_add();
 191                 if (rc)
 192                         goto out_unregister;
 193         }
 194         return 0;
 195
 196 out_unregister:
 197         sysfs_remove_group(&zq->queue->ap_dev.device.kobj,
 198                            &zcrypt_queue_attr_group);
 199 out:
 200         spin_lock(&zcrypt_list_lock);
 201         list_del_init(&zq->list);
 202         spin_unlock(&zcrypt_list_lock);
 203         zcrypt_card_put(zc);
 204         return rc;
 205 }
 206 EXPORT_SYMBOL(zcrypt_queue_register);
 207
 208 /**
 209  * zcrypt_queue_unregister(): Unregister a crypto queue device.
 210  * @zq: Pointer to crypto queue device
 211  *
 212  * Unregister a crypto queue device.
 213  */
 214 void zcrypt_queue_unregister(struct zcrypt_queue *zq)
 215 {
 216         struct zcrypt_card *zc;
 217
 218         ZCRYPT_DBF(DBF_INFO, "queue=%02x.%04x unregister\n",
 219                    AP_QID_CARD(zq->queue->qid), AP_QID_QUEUE(zq->queue->qid));
 220
 221         zc = zq->zcard;
 222         spin_lock(&zcrypt_list_lock);
 223         list_del_init(&zq->list);
 224         spin_unlock(&zcrypt_list_lock);
 225         if (zq->ops->rng)
 226                 zcrypt_rng_device_remove();
 227         sysfs_remove_group(&zq->queue->ap_dev.device.kobj,
 228                            &zcrypt_queue_attr_group);
 229         zcrypt_card_put(zc);
 230         zcrypt_queue_put(zq);
 231 }
 232 EXPORT_SYMBOL(zcrypt_queue_unregister);