xref: /linux/drivers/s390/crypto/zcrypt_queue.c (revision 4b660dbd9ee2059850fd30e0df420ca7a38a1856)
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 zcrypt_queue *zq = dev_get_drvdata(dev);
44 	struct ap_queue *aq = to_ap_queue(dev);
45 	int online = aq->config && !aq->chkstop && zq->online ? 1 : 0;
46 
47 	return sysfs_emit(buf, "%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 zcrypt_queue *zq = dev_get_drvdata(dev);
55 	struct ap_queue *aq = to_ap_queue(dev);
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 		       aq->chkstop || aq->card->chkstop))
64 		return -ENODEV;
65 	if (online && !zc->online)
66 		return -EINVAL;
67 	zq->online = online;
68 
69 	ZCRYPT_DBF_INFO("%s queue=%02x.%04x online=%d\n",
70 			__func__, AP_QID_CARD(zq->queue->qid),
71 			AP_QID_QUEUE(zq->queue->qid), 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 = dev_get_drvdata(dev);
87 
88 	return sysfs_emit(buf, "%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 reply_buf_size)
115 {
116 	struct zcrypt_queue *zq;
117 
118 	zq = kzalloc(sizeof(*zq), GFP_KERNEL);
119 	if (!zq)
120 		return NULL;
121 	zq->reply.msg = kmalloc(reply_buf_size, GFP_KERNEL);
122 	if (!zq->reply.msg)
123 		goto out_free;
124 	zq->reply.bufsize = reply_buf_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 = dev_get_drvdata(&zq->queue->card->ap_dev.device);
174 	zcrypt_card_get(zc);
175 	zq->zcard = zc;
176 	zq->online = 1;	/* New devices are online by default. */
177 
178 	ZCRYPT_DBF_INFO("%s queue=%02x.%04x register online=1\n",
179 			__func__, AP_QID_CARD(zq->queue->qid),
180 			AP_QID_QUEUE(zq->queue->qid));
181 
182 	list_add_tail(&zq->list, &zc->zqueues);
183 	spin_unlock(&zcrypt_list_lock);
184 
185 	rc = sysfs_create_group(&zq->queue->ap_dev.device.kobj,
186 				&zcrypt_queue_attr_group);
187 	if (rc)
188 		goto out;
189 
190 	if (zq->ops->rng) {
191 		rc = zcrypt_rng_device_add();
192 		if (rc)
193 			goto out_unregister;
194 	}
195 	return 0;
196 
197 out_unregister:
198 	sysfs_remove_group(&zq->queue->ap_dev.device.kobj,
199 			   &zcrypt_queue_attr_group);
200 out:
201 	spin_lock(&zcrypt_list_lock);
202 	list_del_init(&zq->list);
203 	spin_unlock(&zcrypt_list_lock);
204 	zcrypt_card_put(zc);
205 	return rc;
206 }
207 EXPORT_SYMBOL(zcrypt_queue_register);
208 
209 /**
210  * zcrypt_queue_unregister(): Unregister a crypto queue device.
211  * @zq: Pointer to crypto queue device
212  *
213  * Unregister a crypto queue device.
214  */
215 void zcrypt_queue_unregister(struct zcrypt_queue *zq)
216 {
217 	struct zcrypt_card *zc;
218 
219 	ZCRYPT_DBF_INFO("%s queue=%02x.%04x unregister\n",
220 			__func__, AP_QID_CARD(zq->queue->qid),
221 			AP_QID_QUEUE(zq->queue->qid));
222 
223 	zc = zq->zcard;
224 	spin_lock(&zcrypt_list_lock);
225 	list_del_init(&zq->list);
226 	spin_unlock(&zcrypt_list_lock);
227 	if (zq->ops->rng)
228 		zcrypt_rng_device_remove();
229 	sysfs_remove_group(&zq->queue->ap_dev.device.kobj,
230 			   &zcrypt_queue_attr_group);
231 	zcrypt_card_put(zc);
232 	zcrypt_queue_put(zq);
233 }
234 EXPORT_SYMBOL(zcrypt_queue_unregister);
235