xref: /linux/drivers/s390/crypto/zcrypt_card.c (revision 172cdcaefea5c297fdb3d20b7d5aff60ae4fbce6)
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 card devices.
37  */
38 
39 static ssize_t type_show(struct device *dev,
40 			 struct device_attribute *attr, char *buf)
41 {
42 	struct zcrypt_card *zc = to_ap_card(dev)->private;
43 
44 	return scnprintf(buf, PAGE_SIZE, "%s\n", zc->type_string);
45 }
46 
47 static DEVICE_ATTR_RO(type);
48 
49 static ssize_t online_show(struct device *dev,
50 			   struct device_attribute *attr,
51 			   char *buf)
52 {
53 	struct ap_card *ac = to_ap_card(dev);
54 	struct zcrypt_card *zc = ac->private;
55 	int online = ac->config && zc->online ? 1 : 0;
56 
57 	return scnprintf(buf, PAGE_SIZE, "%d\n", online);
58 }
59 
60 static ssize_t online_store(struct device *dev,
61 			    struct device_attribute *attr,
62 			    const char *buf, size_t count)
63 {
64 	struct ap_card *ac = to_ap_card(dev);
65 	struct zcrypt_card *zc = ac->private;
66 	struct zcrypt_queue *zq;
67 	int online, id;
68 
69 	if (sscanf(buf, "%d\n", &online) != 1 || online < 0 || online > 1)
70 		return -EINVAL;
71 
72 	if (online && !ac->config)
73 		return -ENODEV;
74 
75 	zc->online = online;
76 	id = zc->card->id;
77 
78 	ZCRYPT_DBF(DBF_INFO, "card=%02x online=%d\n", id, online);
79 
80 	spin_lock(&zcrypt_list_lock);
81 	list_for_each_entry(zq, &zc->zqueues, list)
82 		zcrypt_queue_force_online(zq, online);
83 	spin_unlock(&zcrypt_list_lock);
84 	return count;
85 }
86 
87 static DEVICE_ATTR_RW(online);
88 
89 static ssize_t load_show(struct device *dev,
90 			 struct device_attribute *attr,
91 			 char *buf)
92 {
93 	struct zcrypt_card *zc = to_ap_card(dev)->private;
94 
95 	return scnprintf(buf, PAGE_SIZE, "%d\n", atomic_read(&zc->load));
96 }
97 
98 static DEVICE_ATTR_RO(load);
99 
100 static struct attribute *zcrypt_card_attrs[] = {
101 	&dev_attr_type.attr,
102 	&dev_attr_online.attr,
103 	&dev_attr_load.attr,
104 	NULL,
105 };
106 
107 static const struct attribute_group zcrypt_card_attr_group = {
108 	.attrs = zcrypt_card_attrs,
109 };
110 
111 struct zcrypt_card *zcrypt_card_alloc(void)
112 {
113 	struct zcrypt_card *zc;
114 
115 	zc = kzalloc(sizeof(struct zcrypt_card), GFP_KERNEL);
116 	if (!zc)
117 		return NULL;
118 	INIT_LIST_HEAD(&zc->list);
119 	INIT_LIST_HEAD(&zc->zqueues);
120 	kref_init(&zc->refcount);
121 	return zc;
122 }
123 EXPORT_SYMBOL(zcrypt_card_alloc);
124 
125 void zcrypt_card_free(struct zcrypt_card *zc)
126 {
127 	kfree(zc);
128 }
129 EXPORT_SYMBOL(zcrypt_card_free);
130 
131 static void zcrypt_card_release(struct kref *kref)
132 {
133 	struct zcrypt_card *zdev =
134 		container_of(kref, struct zcrypt_card, refcount);
135 	zcrypt_card_free(zdev);
136 }
137 
138 void zcrypt_card_get(struct zcrypt_card *zc)
139 {
140 	kref_get(&zc->refcount);
141 }
142 EXPORT_SYMBOL(zcrypt_card_get);
143 
144 int zcrypt_card_put(struct zcrypt_card *zc)
145 {
146 	return kref_put(&zc->refcount, zcrypt_card_release);
147 }
148 EXPORT_SYMBOL(zcrypt_card_put);
149 
150 /**
151  * zcrypt_card_register() - Register a crypto card device.
152  * @zc: Pointer to a crypto card device
153  *
154  * Register a crypto card device. Returns 0 if successful.
155  */
156 int zcrypt_card_register(struct zcrypt_card *zc)
157 {
158 	int rc;
159 
160 	spin_lock(&zcrypt_list_lock);
161 	list_add_tail(&zc->list, &zcrypt_card_list);
162 	spin_unlock(&zcrypt_list_lock);
163 
164 	zc->online = 1;
165 
166 	ZCRYPT_DBF(DBF_INFO, "card=%02x register online=1\n", zc->card->id);
167 
168 	rc = sysfs_create_group(&zc->card->ap_dev.device.kobj,
169 				&zcrypt_card_attr_group);
170 	if (rc) {
171 		spin_lock(&zcrypt_list_lock);
172 		list_del_init(&zc->list);
173 		spin_unlock(&zcrypt_list_lock);
174 	}
175 
176 	return rc;
177 }
178 EXPORT_SYMBOL(zcrypt_card_register);
179 
180 /**
181  * zcrypt_card_unregister(): Unregister a crypto card device.
182  * @zc: Pointer to crypto card device
183  *
184  * Unregister a crypto card device.
185  */
186 void zcrypt_card_unregister(struct zcrypt_card *zc)
187 {
188 	ZCRYPT_DBF(DBF_INFO, "card=%02x unregister\n", zc->card->id);
189 
190 	spin_lock(&zcrypt_list_lock);
191 	list_del_init(&zc->list);
192 	spin_unlock(&zcrypt_list_lock);
193 	sysfs_remove_group(&zc->card->ap_dev.device.kobj,
194 			   &zcrypt_card_attr_group);
195 	zcrypt_card_put(zc);
196 }
197 EXPORT_SYMBOL(zcrypt_card_unregister);
198