s390/crypto/zcrypt_card.c

0001 // SPDX-License-Identifier: GPL-2.0+
0002 /*
0003  *  Copyright IBM Corp. 2001, 2012
0004  *  Author(s): Robert Burroughs
0005  *         Eric Rossman (edrossma@us.ibm.com)
0006  *         Cornelia Huck <cornelia.huck@de.ibm.com>
0007  *
0008  *  Hotplug & misc device support: Jochen Roehrig (roehrig@de.ibm.com)
0009  *  Major cleanup & driver split: Martin Schwidefsky <schwidefsky@de.ibm.com>
0010  *                Ralph Wuerthner <rwuerthn@de.ibm.com>
0011  *  MSGTYPE restruct:         Holger Dengler <hd@linux.vnet.ibm.com>
0012  */
0013
0014 #include <linux/module.h>
0015 #include <linux/init.h>
0016 #include <linux/interrupt.h>
0017 #include <linux/miscdevice.h>
0018 #include <linux/fs.h>
0019 #include <linux/proc_fs.h>
0020 #include <linux/seq_file.h>
0021 #include <linux/compat.h>
0022 #include <linux/slab.h>
0023 #include <linux/atomic.h>
0024 #include <linux/uaccess.h>
0025 #include <linux/hw_random.h>
0026 #include <linux/debugfs.h>
0027 #include <asm/debug.h>
0028
0029 #include "zcrypt_debug.h"
0030 #include "zcrypt_api.h"
0031
0032 #include "zcrypt_msgtype6.h"
0033 #include "zcrypt_msgtype50.h"
0034
0035 /*
0036  * Device attributes common for all crypto card devices.
0037  */
0038
0039 static ssize_t type_show(struct device *dev,
0040              struct device_attribute *attr, char *buf)
0041 {
0042     struct zcrypt_card *zc = dev_get_drvdata(dev);
0043
0044     return scnprintf(buf, PAGE_SIZE, "%s\n", zc->type_string);
0045 }
0046
0047 static DEVICE_ATTR_RO(type);
0048
0049 static ssize_t online_show(struct device *dev,
0050                struct device_attribute *attr,
0051                char *buf)
0052 {
0053     struct zcrypt_card *zc = dev_get_drvdata(dev);
0054     struct ap_card *ac = to_ap_card(dev);
0055     int online = ac->config && zc->online ? 1 : 0;
0056
0057     return scnprintf(buf, PAGE_SIZE, "%d\n", online);
0058 }
0059
0060 static ssize_t online_store(struct device *dev,
0061                 struct device_attribute *attr,
0062                 const char *buf, size_t count)
0063 {
0064     struct zcrypt_card *zc = dev_get_drvdata(dev);
0065     struct ap_card *ac = to_ap_card(dev);
0066     struct zcrypt_queue *zq;
0067     int online, id, i = 0, maxzqs = 0;
0068     struct zcrypt_queue **zq_uelist = NULL;
0069
0070     if (sscanf(buf, "%d\n", &online) != 1 || online < 0 || online > 1)
0071         return -EINVAL;
0072
0073     if (online && !ac->config)
0074         return -ENODEV;
0075
0076     zc->online = online;
0077     id = zc->card->id;
0078
0079     ZCRYPT_DBF_INFO("%s card=%02x online=%d\n", __func__, id, online);
0080
0081     ap_send_online_uevent(&ac->ap_dev, online);
0082
0083     spin_lock(&zcrypt_list_lock);
0084     /*
0085      * As we are in atomic context here, directly sending uevents
0086      * does not work. So collect the zqueues in a dynamic array
0087      * and process them after zcrypt_list_lock release. As we get/put
0088      * the zqueue objects, we make sure they exist after lock release.
0089      */
0090     list_for_each_entry(zq, &zc->zqueues, list)
0091         maxzqs++;
0092     if (maxzqs > 0)
0093         zq_uelist = kcalloc(maxzqs + 1, sizeof(*zq_uelist), GFP_ATOMIC);
0094     list_for_each_entry(zq, &zc->zqueues, list)
0095         if (zcrypt_queue_force_online(zq, online))
0096             if (zq_uelist) {
0097                 zcrypt_queue_get(zq);
0098                 zq_uelist[i++] = zq;
0099             }
0100     spin_unlock(&zcrypt_list_lock);
0101     if (zq_uelist) {
0102         for (i = 0; zq_uelist[i]; i++) {
0103             zq = zq_uelist[i];
0104             ap_send_online_uevent(&zq->queue->ap_dev, online);
0105             zcrypt_queue_put(zq);
0106         }
0107         kfree(zq_uelist);
0108     }
0109
0110     return count;
0111 }
0112
0113 static DEVICE_ATTR_RW(online);
0114
0115 static ssize_t load_show(struct device *dev,
0116              struct device_attribute *attr,
0117              char *buf)
0118 {
0119     struct zcrypt_card *zc = dev_get_drvdata(dev);
0120
0121     return scnprintf(buf, PAGE_SIZE, "%d\n", atomic_read(&zc->load));
0122 }
0123
0124 static DEVICE_ATTR_RO(load);
0125
0126 static struct attribute *zcrypt_card_attrs[] = {
0127     &dev_attr_type.attr,
0128     &dev_attr_online.attr,
0129     &dev_attr_load.attr,
0130     NULL,
0131 };
0132
0133 static const struct attribute_group zcrypt_card_attr_group = {
0134     .attrs = zcrypt_card_attrs,
0135 };
0136
0137 struct zcrypt_card *zcrypt_card_alloc(void)
0138 {
0139     struct zcrypt_card *zc;
0140
0141     zc = kzalloc(sizeof(*zc), GFP_KERNEL);
0142     if (!zc)
0143         return NULL;
0144     INIT_LIST_HEAD(&zc->list);
0145     INIT_LIST_HEAD(&zc->zqueues);
0146     kref_init(&zc->refcount);
0147     return zc;
0148 }
0149 EXPORT_SYMBOL(zcrypt_card_alloc);
0150
0151 void zcrypt_card_free(struct zcrypt_card *zc)
0152 {
0153     kfree(zc);
0154 }
0155 EXPORT_SYMBOL(zcrypt_card_free);
0156
0157 static void zcrypt_card_release(struct kref *kref)
0158 {
0159     struct zcrypt_card *zdev =
0160         container_of(kref, struct zcrypt_card, refcount);
0161     zcrypt_card_free(zdev);
0162 }
0163
0164 void zcrypt_card_get(struct zcrypt_card *zc)
0165 {
0166     kref_get(&zc->refcount);
0167 }
0168 EXPORT_SYMBOL(zcrypt_card_get);
0169
0170 int zcrypt_card_put(struct zcrypt_card *zc)
0171 {
0172     return kref_put(&zc->refcount, zcrypt_card_release);
0173 }
0174 EXPORT_SYMBOL(zcrypt_card_put);
0175
0176 /**
0177  * zcrypt_card_register() - Register a crypto card device.
0178  * @zc: Pointer to a crypto card device
0179  *
0180  * Register a crypto card device. Returns 0 if successful.
0181  */
0182 int zcrypt_card_register(struct zcrypt_card *zc)
0183 {
0184     int rc;
0185
0186     spin_lock(&zcrypt_list_lock);
0187     list_add_tail(&zc->list, &zcrypt_card_list);
0188     spin_unlock(&zcrypt_list_lock);
0189
0190     zc->online = 1;
0191
0192     ZCRYPT_DBF_INFO("%s card=%02x register online=1\n",
0193             __func__, zc->card->id);
0194
0195     rc = sysfs_create_group(&zc->card->ap_dev.device.kobj,
0196                 &zcrypt_card_attr_group);
0197     if (rc) {
0198         spin_lock(&zcrypt_list_lock);
0199         list_del_init(&zc->list);
0200         spin_unlock(&zcrypt_list_lock);
0201     }
0202
0203     return rc;
0204 }
0205 EXPORT_SYMBOL(zcrypt_card_register);
0206
0207 /**
0208  * zcrypt_card_unregister(): Unregister a crypto card device.
0209  * @zc: Pointer to crypto card device
0210  *
0211  * Unregister a crypto card device.
0212  */
0213 void zcrypt_card_unregister(struct zcrypt_card *zc)
0214 {
0215     ZCRYPT_DBF_INFO("%s card=%02x unregister\n",
0216             __func__, zc->card->id);
0217
0218     spin_lock(&zcrypt_list_lock);
0219     list_del_init(&zc->list);
0220     spin_unlock(&zcrypt_list_lock);
0221     sysfs_remove_group(&zc->card->ap_dev.device.kobj,
0222                &zcrypt_card_attr_group);
0223     zcrypt_card_put(zc);
0224 }
0225 EXPORT_SYMBOL(zcrypt_card_unregister);