1 /*
2  *  linux/drivers/s390/crypto/zcrypt_api.c
3  *
4  *  zcrypt 2.1.0
5  *
6  *  Copyright (C)  2001, 2006 IBM Corporation
7  *  Author(s): Robert Burroughs
8  *	       Eric Rossman (edrossma@us.ibm.com)
9  *	       Cornelia Huck <cornelia.huck@de.ibm.com>
10  *
11  *  Hotplug & misc device support: Jochen Roehrig (roehrig@de.ibm.com)
12  *  Major cleanup & driver split: Martin Schwidefsky <schwidefsky@de.ibm.com>
13  *				  Ralph Wuerthner <rwuerthn@de.ibm.com>
14  *
15  * This program is free software; you can redistribute it and/or modify
16  * it under the terms of the GNU General Public License as published by
17  * the Free Software Foundation; either version 2, or (at your option)
18  * any later version.
19  *
20  * This program is distributed in the hope that it will be useful,
21  * but WITHOUT ANY WARRANTY; without even the implied warranty of
22  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
23  * GNU General Public License for more details.
24  *
25  * You should have received a copy of the GNU General Public License
26  * along with this program; if not, write to the Free Software
27  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
28  */
29 
30 #include <linux/module.h>
31 #include <linux/init.h>
32 #include <linux/interrupt.h>
33 #include <linux/miscdevice.h>
34 #include <linux/fs.h>
35 #include <linux/proc_fs.h>
36 #include <linux/seq_file.h>
37 #include <linux/compat.h>
38 #include <linux/slab.h>
39 #include <linux/atomic.h>
40 #include <asm/uaccess.h>
41 #include <linux/hw_random.h>
42 
43 #include "zcrypt_api.h"
44 
45 /*
46  * Module description.
47  */
48 MODULE_AUTHOR("IBM Corporation");
49 MODULE_DESCRIPTION("Cryptographic Coprocessor interface, "
50 		   "Copyright 2001, 2006 IBM Corporation");
51 MODULE_LICENSE("GPL");
52 
53 static DEFINE_SPINLOCK(zcrypt_device_lock);
54 static LIST_HEAD(zcrypt_device_list);
55 static int zcrypt_device_count = 0;
56 static atomic_t zcrypt_open_count = ATOMIC_INIT(0);
57 
58 static int zcrypt_rng_device_add(void);
59 static void zcrypt_rng_device_remove(void);
60 
61 /*
62  * Device attributes common for all crypto devices.
63  */
zcrypt_type_show(struct device * dev,struct device_attribute * attr,char * buf)64 static ssize_t zcrypt_type_show(struct device *dev,
65 				struct device_attribute *attr, char *buf)
66 {
67 	struct zcrypt_device *zdev = to_ap_dev(dev)->private;
68 	return snprintf(buf, PAGE_SIZE, "%s\n", zdev->type_string);
69 }
70 
71 static DEVICE_ATTR(type, 0444, zcrypt_type_show, NULL);
72 
zcrypt_online_show(struct device * dev,struct device_attribute * attr,char * buf)73 static ssize_t zcrypt_online_show(struct device *dev,
74 				  struct device_attribute *attr, char *buf)
75 {
76 	struct zcrypt_device *zdev = to_ap_dev(dev)->private;
77 	return snprintf(buf, PAGE_SIZE, "%d\n", zdev->online);
78 }
79 
zcrypt_online_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)80 static ssize_t zcrypt_online_store(struct device *dev,
81 				   struct device_attribute *attr,
82 				   const char *buf, size_t count)
83 {
84 	struct zcrypt_device *zdev = to_ap_dev(dev)->private;
85 	int online;
86 
87 	if (sscanf(buf, "%d\n", &online) != 1 || online < 0 || online > 1)
88 		return -EINVAL;
89 	zdev->online = online;
90 	if (!online)
91 		ap_flush_queue(zdev->ap_dev);
92 	return count;
93 }
94 
95 static DEVICE_ATTR(online, 0644, zcrypt_online_show, zcrypt_online_store);
96 
97 static struct attribute * zcrypt_device_attrs[] = {
98 	&dev_attr_type.attr,
99 	&dev_attr_online.attr,
100 	NULL,
101 };
102 
103 static struct attribute_group zcrypt_device_attr_group = {
104 	.attrs = zcrypt_device_attrs,
105 };
106 
107 /**
108  * __zcrypt_increase_preference(): Increase preference of a crypto device.
109  * @zdev: Pointer the crypto device
110  *
111  * Move the device towards the head of the device list.
112  * Need to be called while holding the zcrypt device list lock.
113  * Note: cards with speed_rating of 0 are kept at the end of the list.
114  */
__zcrypt_increase_preference(struct zcrypt_device * zdev)115 static void __zcrypt_increase_preference(struct zcrypt_device *zdev)
116 {
117 	struct zcrypt_device *tmp;
118 	struct list_head *l;
119 
120 	if (zdev->speed_rating == 0)
121 		return;
122 	for (l = zdev->list.prev; l != &zcrypt_device_list; l = l->prev) {
123 		tmp = list_entry(l, struct zcrypt_device, list);
124 		if ((tmp->request_count + 1) * tmp->speed_rating <=
125 		    (zdev->request_count + 1) * zdev->speed_rating &&
126 		    tmp->speed_rating != 0)
127 			break;
128 	}
129 	if (l == zdev->list.prev)
130 		return;
131 	/* Move zdev behind l */
132 	list_move(&zdev->list, l);
133 }
134 
135 /**
136  * __zcrypt_decrease_preference(): Decrease preference of a crypto device.
137  * @zdev: Pointer to a crypto device.
138  *
139  * Move the device towards the tail of the device list.
140  * Need to be called while holding the zcrypt device list lock.
141  * Note: cards with speed_rating of 0 are kept at the end of the list.
142  */
__zcrypt_decrease_preference(struct zcrypt_device * zdev)143 static void __zcrypt_decrease_preference(struct zcrypt_device *zdev)
144 {
145 	struct zcrypt_device *tmp;
146 	struct list_head *l;
147 
148 	if (zdev->speed_rating == 0)
149 		return;
150 	for (l = zdev->list.next; l != &zcrypt_device_list; l = l->next) {
151 		tmp = list_entry(l, struct zcrypt_device, list);
152 		if ((tmp->request_count + 1) * tmp->speed_rating >
153 		    (zdev->request_count + 1) * zdev->speed_rating ||
154 		    tmp->speed_rating == 0)
155 			break;
156 	}
157 	if (l == zdev->list.next)
158 		return;
159 	/* Move zdev before l */
160 	list_move_tail(&zdev->list, l);
161 }
162 
zcrypt_device_release(struct kref * kref)163 static void zcrypt_device_release(struct kref *kref)
164 {
165 	struct zcrypt_device *zdev =
166 		container_of(kref, struct zcrypt_device, refcount);
167 	zcrypt_device_free(zdev);
168 }
169 
zcrypt_device_get(struct zcrypt_device * zdev)170 void zcrypt_device_get(struct zcrypt_device *zdev)
171 {
172 	kref_get(&zdev->refcount);
173 }
174 EXPORT_SYMBOL(zcrypt_device_get);
175 
zcrypt_device_put(struct zcrypt_device * zdev)176 int zcrypt_device_put(struct zcrypt_device *zdev)
177 {
178 	return kref_put(&zdev->refcount, zcrypt_device_release);
179 }
180 EXPORT_SYMBOL(zcrypt_device_put);
181 
zcrypt_device_alloc(size_t max_response_size)182 struct zcrypt_device *zcrypt_device_alloc(size_t max_response_size)
183 {
184 	struct zcrypt_device *zdev;
185 
186 	zdev = kzalloc(sizeof(struct zcrypt_device), GFP_KERNEL);
187 	if (!zdev)
188 		return NULL;
189 	zdev->reply.message = kmalloc(max_response_size, GFP_KERNEL);
190 	if (!zdev->reply.message)
191 		goto out_free;
192 	zdev->reply.length = max_response_size;
193 	spin_lock_init(&zdev->lock);
194 	INIT_LIST_HEAD(&zdev->list);
195 	return zdev;
196 
197 out_free:
198 	kfree(zdev);
199 	return NULL;
200 }
201 EXPORT_SYMBOL(zcrypt_device_alloc);
202 
zcrypt_device_free(struct zcrypt_device * zdev)203 void zcrypt_device_free(struct zcrypt_device *zdev)
204 {
205 	kfree(zdev->reply.message);
206 	kfree(zdev);
207 }
208 EXPORT_SYMBOL(zcrypt_device_free);
209 
210 /**
211  * zcrypt_device_register() - Register a crypto device.
212  * @zdev: Pointer to a crypto device
213  *
214  * Register a crypto device. Returns 0 if successful.
215  */
zcrypt_device_register(struct zcrypt_device * zdev)216 int zcrypt_device_register(struct zcrypt_device *zdev)
217 {
218 	int rc;
219 
220 	rc = sysfs_create_group(&zdev->ap_dev->device.kobj,
221 				&zcrypt_device_attr_group);
222 	if (rc)
223 		goto out;
224 	get_device(&zdev->ap_dev->device);
225 	kref_init(&zdev->refcount);
226 	spin_lock_bh(&zcrypt_device_lock);
227 	zdev->online = 1;	/* New devices are online by default. */
228 	list_add_tail(&zdev->list, &zcrypt_device_list);
229 	__zcrypt_increase_preference(zdev);
230 	zcrypt_device_count++;
231 	spin_unlock_bh(&zcrypt_device_lock);
232 	if (zdev->ops->rng) {
233 		rc = zcrypt_rng_device_add();
234 		if (rc)
235 			goto out_unregister;
236 	}
237 	return 0;
238 
239 out_unregister:
240 	spin_lock_bh(&zcrypt_device_lock);
241 	zcrypt_device_count--;
242 	list_del_init(&zdev->list);
243 	spin_unlock_bh(&zcrypt_device_lock);
244 	sysfs_remove_group(&zdev->ap_dev->device.kobj,
245 			   &zcrypt_device_attr_group);
246 	put_device(&zdev->ap_dev->device);
247 	zcrypt_device_put(zdev);
248 out:
249 	return rc;
250 }
251 EXPORT_SYMBOL(zcrypt_device_register);
252 
253 /**
254  * zcrypt_device_unregister(): Unregister a crypto device.
255  * @zdev: Pointer to crypto device
256  *
257  * Unregister a crypto device.
258  */
zcrypt_device_unregister(struct zcrypt_device * zdev)259 void zcrypt_device_unregister(struct zcrypt_device *zdev)
260 {
261 	if (zdev->ops->rng)
262 		zcrypt_rng_device_remove();
263 	spin_lock_bh(&zcrypt_device_lock);
264 	zcrypt_device_count--;
265 	list_del_init(&zdev->list);
266 	spin_unlock_bh(&zcrypt_device_lock);
267 	sysfs_remove_group(&zdev->ap_dev->device.kobj,
268 			   &zcrypt_device_attr_group);
269 	put_device(&zdev->ap_dev->device);
270 	zcrypt_device_put(zdev);
271 }
272 EXPORT_SYMBOL(zcrypt_device_unregister);
273 
274 /**
275  * zcrypt_read (): Not supported beyond zcrypt 1.3.1.
276  *
277  * This function is not supported beyond zcrypt 1.3.1.
278  */
zcrypt_read(struct file * filp,char __user * buf,size_t count,loff_t * f_pos)279 static ssize_t zcrypt_read(struct file *filp, char __user *buf,
280 			   size_t count, loff_t *f_pos)
281 {
282 	return -EPERM;
283 }
284 
285 /**
286  * zcrypt_write(): Not allowed.
287  *
288  * Write is is not allowed
289  */
zcrypt_write(struct file * filp,const char __user * buf,size_t count,loff_t * f_pos)290 static ssize_t zcrypt_write(struct file *filp, const char __user *buf,
291 			    size_t count, loff_t *f_pos)
292 {
293 	return -EPERM;
294 }
295 
296 /**
297  * zcrypt_open(): Count number of users.
298  *
299  * Device open function to count number of users.
300  */
zcrypt_open(struct inode * inode,struct file * filp)301 static int zcrypt_open(struct inode *inode, struct file *filp)
302 {
303 	atomic_inc(&zcrypt_open_count);
304 	return nonseekable_open(inode, filp);
305 }
306 
307 /**
308  * zcrypt_release(): Count number of users.
309  *
310  * Device close function to count number of users.
311  */
zcrypt_release(struct inode * inode,struct file * filp)312 static int zcrypt_release(struct inode *inode, struct file *filp)
313 {
314 	atomic_dec(&zcrypt_open_count);
315 	return 0;
316 }
317 
318 /*
319  * zcrypt ioctls.
320  */
zcrypt_rsa_modexpo(struct ica_rsa_modexpo * mex)321 static long zcrypt_rsa_modexpo(struct ica_rsa_modexpo *mex)
322 {
323 	struct zcrypt_device *zdev;
324 	int rc;
325 
326 	if (mex->outputdatalength < mex->inputdatalength)
327 		return -EINVAL;
328 	/*
329 	 * As long as outputdatalength is big enough, we can set the
330 	 * outputdatalength equal to the inputdatalength, since that is the
331 	 * number of bytes we will copy in any case
332 	 */
333 	mex->outputdatalength = mex->inputdatalength;
334 
335 	spin_lock_bh(&zcrypt_device_lock);
336 	list_for_each_entry(zdev, &zcrypt_device_list, list) {
337 		if (!zdev->online ||
338 		    !zdev->ops->rsa_modexpo ||
339 		    zdev->min_mod_size > mex->inputdatalength ||
340 		    zdev->max_mod_size < mex->inputdatalength)
341 			continue;
342 		zcrypt_device_get(zdev);
343 		get_device(&zdev->ap_dev->device);
344 		zdev->request_count++;
345 		__zcrypt_decrease_preference(zdev);
346 		if (try_module_get(zdev->ap_dev->drv->driver.owner)) {
347 			spin_unlock_bh(&zcrypt_device_lock);
348 			rc = zdev->ops->rsa_modexpo(zdev, mex);
349 			spin_lock_bh(&zcrypt_device_lock);
350 			module_put(zdev->ap_dev->drv->driver.owner);
351 		}
352 		else
353 			rc = -EAGAIN;
354 		zdev->request_count--;
355 		__zcrypt_increase_preference(zdev);
356 		put_device(&zdev->ap_dev->device);
357 		zcrypt_device_put(zdev);
358 		spin_unlock_bh(&zcrypt_device_lock);
359 		return rc;
360 	}
361 	spin_unlock_bh(&zcrypt_device_lock);
362 	return -ENODEV;
363 }
364 
zcrypt_rsa_crt(struct ica_rsa_modexpo_crt * crt)365 static long zcrypt_rsa_crt(struct ica_rsa_modexpo_crt *crt)
366 {
367 	struct zcrypt_device *zdev;
368 	unsigned long long z1, z2, z3;
369 	int rc, copied;
370 
371 	if (crt->outputdatalength < crt->inputdatalength ||
372 	    (crt->inputdatalength & 1))
373 		return -EINVAL;
374 	/*
375 	 * As long as outputdatalength is big enough, we can set the
376 	 * outputdatalength equal to the inputdatalength, since that is the
377 	 * number of bytes we will copy in any case
378 	 */
379 	crt->outputdatalength = crt->inputdatalength;
380 
381 	copied = 0;
382  restart:
383 	spin_lock_bh(&zcrypt_device_lock);
384 	list_for_each_entry(zdev, &zcrypt_device_list, list) {
385 		if (!zdev->online ||
386 		    !zdev->ops->rsa_modexpo_crt ||
387 		    zdev->min_mod_size > crt->inputdatalength ||
388 		    zdev->max_mod_size < crt->inputdatalength)
389 			continue;
390 		if (zdev->short_crt && crt->inputdatalength > 240) {
391 			/*
392 			 * Check inputdata for leading zeros for cards
393 			 * that can't handle np_prime, bp_key, or
394 			 * u_mult_inv > 128 bytes.
395 			 */
396 			if (copied == 0) {
397 				unsigned int len;
398 				spin_unlock_bh(&zcrypt_device_lock);
399 				/* len is max 256 / 2 - 120 = 8
400 				 * For bigger device just assume len of leading
401 				 * 0s is 8 as stated in the requirements for
402 				 * ica_rsa_modexpo_crt struct in zcrypt.h.
403 				 */
404 				if (crt->inputdatalength <= 256)
405 					len = crt->inputdatalength / 2 - 120;
406 				else
407 					len = 8;
408 				if (len > sizeof(z1))
409 					return -EFAULT;
410 				z1 = z2 = z3 = 0;
411 				if (copy_from_user(&z1, crt->np_prime, len) ||
412 				    copy_from_user(&z2, crt->bp_key, len) ||
413 				    copy_from_user(&z3, crt->u_mult_inv, len))
414 					return -EFAULT;
415 				z1 = z2 = z3 = 0;
416 				copied = 1;
417 				/*
418 				 * We have to restart device lookup -
419 				 * the device list may have changed by now.
420 				 */
421 				goto restart;
422 			}
423 			if (z1 != 0ULL || z2 != 0ULL || z3 != 0ULL)
424 				/* The device can't handle this request. */
425 				continue;
426 		}
427 		zcrypt_device_get(zdev);
428 		get_device(&zdev->ap_dev->device);
429 		zdev->request_count++;
430 		__zcrypt_decrease_preference(zdev);
431 		if (try_module_get(zdev->ap_dev->drv->driver.owner)) {
432 			spin_unlock_bh(&zcrypt_device_lock);
433 			rc = zdev->ops->rsa_modexpo_crt(zdev, crt);
434 			spin_lock_bh(&zcrypt_device_lock);
435 			module_put(zdev->ap_dev->drv->driver.owner);
436 		}
437 		else
438 			rc = -EAGAIN;
439 		zdev->request_count--;
440 		__zcrypt_increase_preference(zdev);
441 		put_device(&zdev->ap_dev->device);
442 		zcrypt_device_put(zdev);
443 		spin_unlock_bh(&zcrypt_device_lock);
444 		return rc;
445 	}
446 	spin_unlock_bh(&zcrypt_device_lock);
447 	return -ENODEV;
448 }
449 
zcrypt_send_cprb(struct ica_xcRB * xcRB)450 static long zcrypt_send_cprb(struct ica_xcRB *xcRB)
451 {
452 	struct zcrypt_device *zdev;
453 	int rc;
454 
455 	spin_lock_bh(&zcrypt_device_lock);
456 	list_for_each_entry(zdev, &zcrypt_device_list, list) {
457 		if (!zdev->online || !zdev->ops->send_cprb ||
458 		    (xcRB->user_defined != AUTOSELECT &&
459 			AP_QID_DEVICE(zdev->ap_dev->qid) != xcRB->user_defined)
460 		    )
461 			continue;
462 		zcrypt_device_get(zdev);
463 		get_device(&zdev->ap_dev->device);
464 		zdev->request_count++;
465 		__zcrypt_decrease_preference(zdev);
466 		if (try_module_get(zdev->ap_dev->drv->driver.owner)) {
467 			spin_unlock_bh(&zcrypt_device_lock);
468 			rc = zdev->ops->send_cprb(zdev, xcRB);
469 			spin_lock_bh(&zcrypt_device_lock);
470 			module_put(zdev->ap_dev->drv->driver.owner);
471 		}
472 		else
473 			rc = -EAGAIN;
474 		zdev->request_count--;
475 		__zcrypt_increase_preference(zdev);
476 		put_device(&zdev->ap_dev->device);
477 		zcrypt_device_put(zdev);
478 		spin_unlock_bh(&zcrypt_device_lock);
479 		return rc;
480 	}
481 	spin_unlock_bh(&zcrypt_device_lock);
482 	return -ENODEV;
483 }
484 
zcrypt_rng(char * buffer)485 static long zcrypt_rng(char *buffer)
486 {
487 	struct zcrypt_device *zdev;
488 	int rc;
489 
490 	spin_lock_bh(&zcrypt_device_lock);
491 	list_for_each_entry(zdev, &zcrypt_device_list, list) {
492 		if (!zdev->online || !zdev->ops->rng)
493 			continue;
494 		zcrypt_device_get(zdev);
495 		get_device(&zdev->ap_dev->device);
496 		zdev->request_count++;
497 		__zcrypt_decrease_preference(zdev);
498 		if (try_module_get(zdev->ap_dev->drv->driver.owner)) {
499 			spin_unlock_bh(&zcrypt_device_lock);
500 			rc = zdev->ops->rng(zdev, buffer);
501 			spin_lock_bh(&zcrypt_device_lock);
502 			module_put(zdev->ap_dev->drv->driver.owner);
503 		} else
504 			rc = -EAGAIN;
505 		zdev->request_count--;
506 		__zcrypt_increase_preference(zdev);
507 		put_device(&zdev->ap_dev->device);
508 		zcrypt_device_put(zdev);
509 		spin_unlock_bh(&zcrypt_device_lock);
510 		return rc;
511 	}
512 	spin_unlock_bh(&zcrypt_device_lock);
513 	return -ENODEV;
514 }
515 
zcrypt_status_mask(char status[AP_DEVICES])516 static void zcrypt_status_mask(char status[AP_DEVICES])
517 {
518 	struct zcrypt_device *zdev;
519 
520 	memset(status, 0, sizeof(char) * AP_DEVICES);
521 	spin_lock_bh(&zcrypt_device_lock);
522 	list_for_each_entry(zdev, &zcrypt_device_list, list)
523 		status[AP_QID_DEVICE(zdev->ap_dev->qid)] =
524 			zdev->online ? zdev->user_space_type : 0x0d;
525 	spin_unlock_bh(&zcrypt_device_lock);
526 }
527 
zcrypt_qdepth_mask(char qdepth[AP_DEVICES])528 static void zcrypt_qdepth_mask(char qdepth[AP_DEVICES])
529 {
530 	struct zcrypt_device *zdev;
531 
532 	memset(qdepth, 0, sizeof(char)	* AP_DEVICES);
533 	spin_lock_bh(&zcrypt_device_lock);
534 	list_for_each_entry(zdev, &zcrypt_device_list, list) {
535 		spin_lock(&zdev->ap_dev->lock);
536 		qdepth[AP_QID_DEVICE(zdev->ap_dev->qid)] =
537 			zdev->ap_dev->pendingq_count +
538 			zdev->ap_dev->requestq_count;
539 		spin_unlock(&zdev->ap_dev->lock);
540 	}
541 	spin_unlock_bh(&zcrypt_device_lock);
542 }
543 
zcrypt_perdev_reqcnt(int reqcnt[AP_DEVICES])544 static void zcrypt_perdev_reqcnt(int reqcnt[AP_DEVICES])
545 {
546 	struct zcrypt_device *zdev;
547 
548 	memset(reqcnt, 0, sizeof(int) * AP_DEVICES);
549 	spin_lock_bh(&zcrypt_device_lock);
550 	list_for_each_entry(zdev, &zcrypt_device_list, list) {
551 		spin_lock(&zdev->ap_dev->lock);
552 		reqcnt[AP_QID_DEVICE(zdev->ap_dev->qid)] =
553 			zdev->ap_dev->total_request_count;
554 		spin_unlock(&zdev->ap_dev->lock);
555 	}
556 	spin_unlock_bh(&zcrypt_device_lock);
557 }
558 
zcrypt_pendingq_count(void)559 static int zcrypt_pendingq_count(void)
560 {
561 	struct zcrypt_device *zdev;
562 	int pendingq_count = 0;
563 
564 	spin_lock_bh(&zcrypt_device_lock);
565 	list_for_each_entry(zdev, &zcrypt_device_list, list) {
566 		spin_lock(&zdev->ap_dev->lock);
567 		pendingq_count += zdev->ap_dev->pendingq_count;
568 		spin_unlock(&zdev->ap_dev->lock);
569 	}
570 	spin_unlock_bh(&zcrypt_device_lock);
571 	return pendingq_count;
572 }
573 
zcrypt_requestq_count(void)574 static int zcrypt_requestq_count(void)
575 {
576 	struct zcrypt_device *zdev;
577 	int requestq_count = 0;
578 
579 	spin_lock_bh(&zcrypt_device_lock);
580 	list_for_each_entry(zdev, &zcrypt_device_list, list) {
581 		spin_lock(&zdev->ap_dev->lock);
582 		requestq_count += zdev->ap_dev->requestq_count;
583 		spin_unlock(&zdev->ap_dev->lock);
584 	}
585 	spin_unlock_bh(&zcrypt_device_lock);
586 	return requestq_count;
587 }
588 
zcrypt_count_type(int type)589 static int zcrypt_count_type(int type)
590 {
591 	struct zcrypt_device *zdev;
592 	int device_count = 0;
593 
594 	spin_lock_bh(&zcrypt_device_lock);
595 	list_for_each_entry(zdev, &zcrypt_device_list, list)
596 		if (zdev->user_space_type == type)
597 			device_count++;
598 	spin_unlock_bh(&zcrypt_device_lock);
599 	return device_count;
600 }
601 
602 /**
603  * zcrypt_ica_status(): Old, depracted combi status call.
604  *
605  * Old, deprecated combi status call.
606  */
zcrypt_ica_status(struct file * filp,unsigned long arg)607 static long zcrypt_ica_status(struct file *filp, unsigned long arg)
608 {
609 	struct ica_z90_status *pstat;
610 	int ret;
611 
612 	pstat = kzalloc(sizeof(*pstat), GFP_KERNEL);
613 	if (!pstat)
614 		return -ENOMEM;
615 	pstat->totalcount = zcrypt_device_count;
616 	pstat->leedslitecount = zcrypt_count_type(ZCRYPT_PCICA);
617 	pstat->leeds2count = zcrypt_count_type(ZCRYPT_PCICC);
618 	pstat->requestqWaitCount = zcrypt_requestq_count();
619 	pstat->pendingqWaitCount = zcrypt_pendingq_count();
620 	pstat->totalOpenCount = atomic_read(&zcrypt_open_count);
621 	pstat->cryptoDomain = ap_domain_index;
622 	zcrypt_status_mask(pstat->status);
623 	zcrypt_qdepth_mask(pstat->qdepth);
624 	ret = 0;
625 	if (copy_to_user((void __user *) arg, pstat, sizeof(*pstat)))
626 		ret = -EFAULT;
627 	kfree(pstat);
628 	return ret;
629 }
630 
zcrypt_unlocked_ioctl(struct file * filp,unsigned int cmd,unsigned long arg)631 static long zcrypt_unlocked_ioctl(struct file *filp, unsigned int cmd,
632 				  unsigned long arg)
633 {
634 	int rc;
635 
636 	switch (cmd) {
637 	case ICARSAMODEXPO: {
638 		struct ica_rsa_modexpo __user *umex = (void __user *) arg;
639 		struct ica_rsa_modexpo mex;
640 		if (copy_from_user(&mex, umex, sizeof(mex)))
641 			return -EFAULT;
642 		do {
643 			rc = zcrypt_rsa_modexpo(&mex);
644 		} while (rc == -EAGAIN);
645 		if (rc)
646 			return rc;
647 		return put_user(mex.outputdatalength, &umex->outputdatalength);
648 	}
649 	case ICARSACRT: {
650 		struct ica_rsa_modexpo_crt __user *ucrt = (void __user *) arg;
651 		struct ica_rsa_modexpo_crt crt;
652 		if (copy_from_user(&crt, ucrt, sizeof(crt)))
653 			return -EFAULT;
654 		do {
655 			rc = zcrypt_rsa_crt(&crt);
656 		} while (rc == -EAGAIN);
657 		if (rc)
658 			return rc;
659 		return put_user(crt.outputdatalength, &ucrt->outputdatalength);
660 	}
661 	case ZSECSENDCPRB: {
662 		struct ica_xcRB __user *uxcRB = (void __user *) arg;
663 		struct ica_xcRB xcRB;
664 		if (copy_from_user(&xcRB, uxcRB, sizeof(xcRB)))
665 			return -EFAULT;
666 		do {
667 			rc = zcrypt_send_cprb(&xcRB);
668 		} while (rc == -EAGAIN);
669 		if (copy_to_user(uxcRB, &xcRB, sizeof(xcRB)))
670 			return -EFAULT;
671 		return rc;
672 	}
673 	case Z90STAT_STATUS_MASK: {
674 		char status[AP_DEVICES];
675 		zcrypt_status_mask(status);
676 		if (copy_to_user((char __user *) arg, status,
677 				 sizeof(char) * AP_DEVICES))
678 			return -EFAULT;
679 		return 0;
680 	}
681 	case Z90STAT_QDEPTH_MASK: {
682 		char qdepth[AP_DEVICES];
683 		zcrypt_qdepth_mask(qdepth);
684 		if (copy_to_user((char __user *) arg, qdepth,
685 				 sizeof(char) * AP_DEVICES))
686 			return -EFAULT;
687 		return 0;
688 	}
689 	case Z90STAT_PERDEV_REQCNT: {
690 		int reqcnt[AP_DEVICES];
691 		zcrypt_perdev_reqcnt(reqcnt);
692 		if (copy_to_user((int __user *) arg, reqcnt,
693 				 sizeof(int) * AP_DEVICES))
694 			return -EFAULT;
695 		return 0;
696 	}
697 	case Z90STAT_REQUESTQ_COUNT:
698 		return put_user(zcrypt_requestq_count(), (int __user *) arg);
699 	case Z90STAT_PENDINGQ_COUNT:
700 		return put_user(zcrypt_pendingq_count(), (int __user *) arg);
701 	case Z90STAT_TOTALOPEN_COUNT:
702 		return put_user(atomic_read(&zcrypt_open_count),
703 				(int __user *) arg);
704 	case Z90STAT_DOMAIN_INDEX:
705 		return put_user(ap_domain_index, (int __user *) arg);
706 	/*
707 	 * Deprecated ioctls. Don't add another device count ioctl,
708 	 * you can count them yourself in the user space with the
709 	 * output of the Z90STAT_STATUS_MASK ioctl.
710 	 */
711 	case ICAZ90STATUS:
712 		return zcrypt_ica_status(filp, arg);
713 	case Z90STAT_TOTALCOUNT:
714 		return put_user(zcrypt_device_count, (int __user *) arg);
715 	case Z90STAT_PCICACOUNT:
716 		return put_user(zcrypt_count_type(ZCRYPT_PCICA),
717 				(int __user *) arg);
718 	case Z90STAT_PCICCCOUNT:
719 		return put_user(zcrypt_count_type(ZCRYPT_PCICC),
720 				(int __user *) arg);
721 	case Z90STAT_PCIXCCMCL2COUNT:
722 		return put_user(zcrypt_count_type(ZCRYPT_PCIXCC_MCL2),
723 				(int __user *) arg);
724 	case Z90STAT_PCIXCCMCL3COUNT:
725 		return put_user(zcrypt_count_type(ZCRYPT_PCIXCC_MCL3),
726 				(int __user *) arg);
727 	case Z90STAT_PCIXCCCOUNT:
728 		return put_user(zcrypt_count_type(ZCRYPT_PCIXCC_MCL2) +
729 				zcrypt_count_type(ZCRYPT_PCIXCC_MCL3),
730 				(int __user *) arg);
731 	case Z90STAT_CEX2CCOUNT:
732 		return put_user(zcrypt_count_type(ZCRYPT_CEX2C),
733 				(int __user *) arg);
734 	case Z90STAT_CEX2ACOUNT:
735 		return put_user(zcrypt_count_type(ZCRYPT_CEX2A),
736 				(int __user *) arg);
737 	default:
738 		/* unknown ioctl number */
739 		return -ENOIOCTLCMD;
740 	}
741 }
742 
743 #ifdef CONFIG_COMPAT
744 /*
745  * ioctl32 conversion routines
746  */
747 struct compat_ica_rsa_modexpo {
748 	compat_uptr_t	inputdata;
749 	unsigned int	inputdatalength;
750 	compat_uptr_t	outputdata;
751 	unsigned int	outputdatalength;
752 	compat_uptr_t	b_key;
753 	compat_uptr_t	n_modulus;
754 };
755 
trans_modexpo32(struct file * filp,unsigned int cmd,unsigned long arg)756 static long trans_modexpo32(struct file *filp, unsigned int cmd,
757 			    unsigned long arg)
758 {
759 	struct compat_ica_rsa_modexpo __user *umex32 = compat_ptr(arg);
760 	struct compat_ica_rsa_modexpo mex32;
761 	struct ica_rsa_modexpo mex64;
762 	long rc;
763 
764 	if (copy_from_user(&mex32, umex32, sizeof(mex32)))
765 		return -EFAULT;
766 	mex64.inputdata = compat_ptr(mex32.inputdata);
767 	mex64.inputdatalength = mex32.inputdatalength;
768 	mex64.outputdata = compat_ptr(mex32.outputdata);
769 	mex64.outputdatalength = mex32.outputdatalength;
770 	mex64.b_key = compat_ptr(mex32.b_key);
771 	mex64.n_modulus = compat_ptr(mex32.n_modulus);
772 	do {
773 		rc = zcrypt_rsa_modexpo(&mex64);
774 	} while (rc == -EAGAIN);
775 	if (!rc)
776 		rc = put_user(mex64.outputdatalength,
777 			      &umex32->outputdatalength);
778 	return rc;
779 }
780 
781 struct compat_ica_rsa_modexpo_crt {
782 	compat_uptr_t	inputdata;
783 	unsigned int	inputdatalength;
784 	compat_uptr_t	outputdata;
785 	unsigned int	outputdatalength;
786 	compat_uptr_t	bp_key;
787 	compat_uptr_t	bq_key;
788 	compat_uptr_t	np_prime;
789 	compat_uptr_t	nq_prime;
790 	compat_uptr_t	u_mult_inv;
791 };
792 
trans_modexpo_crt32(struct file * filp,unsigned int cmd,unsigned long arg)793 static long trans_modexpo_crt32(struct file *filp, unsigned int cmd,
794 				unsigned long arg)
795 {
796 	struct compat_ica_rsa_modexpo_crt __user *ucrt32 = compat_ptr(arg);
797 	struct compat_ica_rsa_modexpo_crt crt32;
798 	struct ica_rsa_modexpo_crt crt64;
799 	long rc;
800 
801 	if (copy_from_user(&crt32, ucrt32, sizeof(crt32)))
802 		return -EFAULT;
803 	crt64.inputdata = compat_ptr(crt32.inputdata);
804 	crt64.inputdatalength = crt32.inputdatalength;
805 	crt64.outputdata=  compat_ptr(crt32.outputdata);
806 	crt64.outputdatalength = crt32.outputdatalength;
807 	crt64.bp_key = compat_ptr(crt32.bp_key);
808 	crt64.bq_key = compat_ptr(crt32.bq_key);
809 	crt64.np_prime = compat_ptr(crt32.np_prime);
810 	crt64.nq_prime = compat_ptr(crt32.nq_prime);
811 	crt64.u_mult_inv = compat_ptr(crt32.u_mult_inv);
812 	do {
813 		rc = zcrypt_rsa_crt(&crt64);
814 	} while (rc == -EAGAIN);
815 	if (!rc)
816 		rc = put_user(crt64.outputdatalength,
817 			      &ucrt32->outputdatalength);
818 	return rc;
819 }
820 
821 struct compat_ica_xcRB {
822 	unsigned short	agent_ID;
823 	unsigned int	user_defined;
824 	unsigned short	request_ID;
825 	unsigned int	request_control_blk_length;
826 	unsigned char	padding1[16 - sizeof (compat_uptr_t)];
827 	compat_uptr_t	request_control_blk_addr;
828 	unsigned int	request_data_length;
829 	char		padding2[16 - sizeof (compat_uptr_t)];
830 	compat_uptr_t	request_data_address;
831 	unsigned int	reply_control_blk_length;
832 	char		padding3[16 - sizeof (compat_uptr_t)];
833 	compat_uptr_t	reply_control_blk_addr;
834 	unsigned int	reply_data_length;
835 	char		padding4[16 - sizeof (compat_uptr_t)];
836 	compat_uptr_t	reply_data_addr;
837 	unsigned short	priority_window;
838 	unsigned int	status;
839 } __attribute__((packed));
840 
trans_xcRB32(struct file * filp,unsigned int cmd,unsigned long arg)841 static long trans_xcRB32(struct file *filp, unsigned int cmd,
842 			 unsigned long arg)
843 {
844 	struct compat_ica_xcRB __user *uxcRB32 = compat_ptr(arg);
845 	struct compat_ica_xcRB xcRB32;
846 	struct ica_xcRB xcRB64;
847 	long rc;
848 
849 	if (copy_from_user(&xcRB32, uxcRB32, sizeof(xcRB32)))
850 		return -EFAULT;
851 	xcRB64.agent_ID = xcRB32.agent_ID;
852 	xcRB64.user_defined = xcRB32.user_defined;
853 	xcRB64.request_ID = xcRB32.request_ID;
854 	xcRB64.request_control_blk_length =
855 		xcRB32.request_control_blk_length;
856 	xcRB64.request_control_blk_addr =
857 		compat_ptr(xcRB32.request_control_blk_addr);
858 	xcRB64.request_data_length =
859 		xcRB32.request_data_length;
860 	xcRB64.request_data_address =
861 		compat_ptr(xcRB32.request_data_address);
862 	xcRB64.reply_control_blk_length =
863 		xcRB32.reply_control_blk_length;
864 	xcRB64.reply_control_blk_addr =
865 		compat_ptr(xcRB32.reply_control_blk_addr);
866 	xcRB64.reply_data_length = xcRB32.reply_data_length;
867 	xcRB64.reply_data_addr =
868 		compat_ptr(xcRB32.reply_data_addr);
869 	xcRB64.priority_window = xcRB32.priority_window;
870 	xcRB64.status = xcRB32.status;
871 	do {
872 		rc = zcrypt_send_cprb(&xcRB64);
873 	} while (rc == -EAGAIN);
874 	xcRB32.reply_control_blk_length = xcRB64.reply_control_blk_length;
875 	xcRB32.reply_data_length = xcRB64.reply_data_length;
876 	xcRB32.status = xcRB64.status;
877 	if (copy_to_user(uxcRB32, &xcRB32, sizeof(xcRB32)))
878 			return -EFAULT;
879 	return rc;
880 }
881 
zcrypt_compat_ioctl(struct file * filp,unsigned int cmd,unsigned long arg)882 static long zcrypt_compat_ioctl(struct file *filp, unsigned int cmd,
883 			 unsigned long arg)
884 {
885 	if (cmd == ICARSAMODEXPO)
886 		return trans_modexpo32(filp, cmd, arg);
887 	if (cmd == ICARSACRT)
888 		return trans_modexpo_crt32(filp, cmd, arg);
889 	if (cmd == ZSECSENDCPRB)
890 		return trans_xcRB32(filp, cmd, arg);
891 	return zcrypt_unlocked_ioctl(filp, cmd, arg);
892 }
893 #endif
894 
895 /*
896  * Misc device file operations.
897  */
898 static const struct file_operations zcrypt_fops = {
899 	.owner		= THIS_MODULE,
900 	.read		= zcrypt_read,
901 	.write		= zcrypt_write,
902 	.unlocked_ioctl	= zcrypt_unlocked_ioctl,
903 #ifdef CONFIG_COMPAT
904 	.compat_ioctl	= zcrypt_compat_ioctl,
905 #endif
906 	.open		= zcrypt_open,
907 	.release	= zcrypt_release,
908 	.llseek		= no_llseek,
909 };
910 
911 /*
912  * Misc device.
913  */
914 static struct miscdevice zcrypt_misc_device = {
915 	.minor	    = MISC_DYNAMIC_MINOR,
916 	.name	    = "z90crypt",
917 	.fops	    = &zcrypt_fops,
918 };
919 
920 /*
921  * Deprecated /proc entry support.
922  */
923 static struct proc_dir_entry *zcrypt_entry;
924 
sprintcl(struct seq_file * m,unsigned char * addr,unsigned int len)925 static void sprintcl(struct seq_file *m, unsigned char *addr, unsigned int len)
926 {
927 	int i;
928 
929 	for (i = 0; i < len; i++)
930 		seq_printf(m, "%01x", (unsigned int) addr[i]);
931 	seq_putc(m, ' ');
932 }
933 
sprintrw(struct seq_file * m,unsigned char * addr,unsigned int len)934 static void sprintrw(struct seq_file *m, unsigned char *addr, unsigned int len)
935 {
936 	int inl, c, cx;
937 
938 	seq_printf(m, "	   ");
939 	inl = 0;
940 	for (c = 0; c < (len / 16); c++) {
941 		sprintcl(m, addr+inl, 16);
942 		inl += 16;
943 	}
944 	cx = len%16;
945 	if (cx) {
946 		sprintcl(m, addr+inl, cx);
947 		inl += cx;
948 	}
949 	seq_putc(m, '\n');
950 }
951 
sprinthx(unsigned char * title,struct seq_file * m,unsigned char * addr,unsigned int len)952 static void sprinthx(unsigned char *title, struct seq_file *m,
953 		     unsigned char *addr, unsigned int len)
954 {
955 	int inl, r, rx;
956 
957 	seq_printf(m, "\n%s\n", title);
958 	inl = 0;
959 	for (r = 0; r < (len / 64); r++) {
960 		sprintrw(m, addr+inl, 64);
961 		inl += 64;
962 	}
963 	rx = len % 64;
964 	if (rx) {
965 		sprintrw(m, addr+inl, rx);
966 		inl += rx;
967 	}
968 	seq_putc(m, '\n');
969 }
970 
sprinthx4(unsigned char * title,struct seq_file * m,unsigned int * array,unsigned int len)971 static void sprinthx4(unsigned char *title, struct seq_file *m,
972 		      unsigned int *array, unsigned int len)
973 {
974 	int r;
975 
976 	seq_printf(m, "\n%s\n", title);
977 	for (r = 0; r < len; r++) {
978 		if ((r % 8) == 0)
979 			seq_printf(m, "    ");
980 		seq_printf(m, "%08X ", array[r]);
981 		if ((r % 8) == 7)
982 			seq_putc(m, '\n');
983 	}
984 	seq_putc(m, '\n');
985 }
986 
zcrypt_proc_show(struct seq_file * m,void * v)987 static int zcrypt_proc_show(struct seq_file *m, void *v)
988 {
989 	char workarea[sizeof(int) * AP_DEVICES];
990 
991 	seq_printf(m, "\nzcrypt version: %d.%d.%d\n",
992 		   ZCRYPT_VERSION, ZCRYPT_RELEASE, ZCRYPT_VARIANT);
993 	seq_printf(m, "Cryptographic domain: %d\n", ap_domain_index);
994 	seq_printf(m, "Total device count: %d\n", zcrypt_device_count);
995 	seq_printf(m, "PCICA count: %d\n", zcrypt_count_type(ZCRYPT_PCICA));
996 	seq_printf(m, "PCICC count: %d\n", zcrypt_count_type(ZCRYPT_PCICC));
997 	seq_printf(m, "PCIXCC MCL2 count: %d\n",
998 		   zcrypt_count_type(ZCRYPT_PCIXCC_MCL2));
999 	seq_printf(m, "PCIXCC MCL3 count: %d\n",
1000 		   zcrypt_count_type(ZCRYPT_PCIXCC_MCL3));
1001 	seq_printf(m, "CEX2C count: %d\n", zcrypt_count_type(ZCRYPT_CEX2C));
1002 	seq_printf(m, "CEX2A count: %d\n", zcrypt_count_type(ZCRYPT_CEX2A));
1003 	seq_printf(m, "CEX3C count: %d\n", zcrypt_count_type(ZCRYPT_CEX3C));
1004 	seq_printf(m, "CEX3A count: %d\n", zcrypt_count_type(ZCRYPT_CEX3A));
1005 	seq_printf(m, "requestq count: %d\n", zcrypt_requestq_count());
1006 	seq_printf(m, "pendingq count: %d\n", zcrypt_pendingq_count());
1007 	seq_printf(m, "Total open handles: %d\n\n",
1008 		   atomic_read(&zcrypt_open_count));
1009 	zcrypt_status_mask(workarea);
1010 	sprinthx("Online devices: 1=PCICA 2=PCICC 3=PCIXCC(MCL2) "
1011 		 "4=PCIXCC(MCL3) 5=CEX2C 6=CEX2A 7=CEX3C 8=CEX3A",
1012 		 m, workarea, AP_DEVICES);
1013 	zcrypt_qdepth_mask(workarea);
1014 	sprinthx("Waiting work element counts", m, workarea, AP_DEVICES);
1015 	zcrypt_perdev_reqcnt((int *) workarea);
1016 	sprinthx4("Per-device successfully completed request counts",
1017 		  m, (unsigned int *) workarea, AP_DEVICES);
1018 	return 0;
1019 }
1020 
zcrypt_proc_open(struct inode * inode,struct file * file)1021 static int zcrypt_proc_open(struct inode *inode, struct file *file)
1022 {
1023 	return single_open(file, zcrypt_proc_show, NULL);
1024 }
1025 
zcrypt_disable_card(int index)1026 static void zcrypt_disable_card(int index)
1027 {
1028 	struct zcrypt_device *zdev;
1029 
1030 	spin_lock_bh(&zcrypt_device_lock);
1031 	list_for_each_entry(zdev, &zcrypt_device_list, list)
1032 		if (AP_QID_DEVICE(zdev->ap_dev->qid) == index) {
1033 			zdev->online = 0;
1034 			ap_flush_queue(zdev->ap_dev);
1035 			break;
1036 		}
1037 	spin_unlock_bh(&zcrypt_device_lock);
1038 }
1039 
zcrypt_enable_card(int index)1040 static void zcrypt_enable_card(int index)
1041 {
1042 	struct zcrypt_device *zdev;
1043 
1044 	spin_lock_bh(&zcrypt_device_lock);
1045 	list_for_each_entry(zdev, &zcrypt_device_list, list)
1046 		if (AP_QID_DEVICE(zdev->ap_dev->qid) == index) {
1047 			zdev->online = 1;
1048 			break;
1049 		}
1050 	spin_unlock_bh(&zcrypt_device_lock);
1051 }
1052 
zcrypt_proc_write(struct file * file,const char __user * buffer,size_t count,loff_t * pos)1053 static ssize_t zcrypt_proc_write(struct file *file, const char __user *buffer,
1054 				 size_t count, loff_t *pos)
1055 {
1056 	unsigned char *lbuf, *ptr;
1057 	size_t local_count;
1058 	int j;
1059 
1060 	if (count <= 0)
1061 		return 0;
1062 
1063 #define LBUFSIZE 1200UL
1064 	lbuf = kmalloc(LBUFSIZE, GFP_KERNEL);
1065 	if (!lbuf)
1066 		return 0;
1067 
1068 	local_count = min(LBUFSIZE - 1, count);
1069 	if (copy_from_user(lbuf, buffer, local_count) != 0) {
1070 		kfree(lbuf);
1071 		return -EFAULT;
1072 	}
1073 	lbuf[local_count] = '\0';
1074 
1075 	ptr = strstr(lbuf, "Online devices");
1076 	if (!ptr)
1077 		goto out;
1078 	ptr = strstr(ptr, "\n");
1079 	if (!ptr)
1080 		goto out;
1081 	ptr++;
1082 
1083 	if (strstr(ptr, "Waiting work element counts") == NULL)
1084 		goto out;
1085 
1086 	for (j = 0; j < 64 && *ptr; ptr++) {
1087 		/*
1088 		 * '0' for no device, '1' for PCICA, '2' for PCICC,
1089 		 * '3' for PCIXCC_MCL2, '4' for PCIXCC_MCL3,
1090 		 * '5' for CEX2C and '6' for CEX2A'
1091 		 * '7' for CEX3C and '8' for CEX3A
1092 		 */
1093 		if (*ptr >= '0' && *ptr <= '8')
1094 			j++;
1095 		else if (*ptr == 'd' || *ptr == 'D')
1096 			zcrypt_disable_card(j++);
1097 		else if (*ptr == 'e' || *ptr == 'E')
1098 			zcrypt_enable_card(j++);
1099 		else if (*ptr != ' ' && *ptr != '\t')
1100 			break;
1101 	}
1102 out:
1103 	kfree(lbuf);
1104 	return count;
1105 }
1106 
1107 static const struct file_operations zcrypt_proc_fops = {
1108 	.owner		= THIS_MODULE,
1109 	.open		= zcrypt_proc_open,
1110 	.read		= seq_read,
1111 	.llseek		= seq_lseek,
1112 	.release	= single_release,
1113 	.write		= zcrypt_proc_write,
1114 };
1115 
1116 static int zcrypt_rng_device_count;
1117 static u32 *zcrypt_rng_buffer;
1118 static int zcrypt_rng_buffer_index;
1119 static DEFINE_MUTEX(zcrypt_rng_mutex);
1120 
zcrypt_rng_data_read(struct hwrng * rng,u32 * data)1121 static int zcrypt_rng_data_read(struct hwrng *rng, u32 *data)
1122 {
1123 	int rc;
1124 
1125 	/*
1126 	 * We don't need locking here because the RNG API guarantees serialized
1127 	 * read method calls.
1128 	 */
1129 	if (zcrypt_rng_buffer_index == 0) {
1130 		rc = zcrypt_rng((char *) zcrypt_rng_buffer);
1131 		if (rc < 0)
1132 			return -EIO;
1133 		zcrypt_rng_buffer_index = rc / sizeof *data;
1134 	}
1135 	*data = zcrypt_rng_buffer[--zcrypt_rng_buffer_index];
1136 	return sizeof *data;
1137 }
1138 
1139 static struct hwrng zcrypt_rng_dev = {
1140 	.name		= "zcrypt",
1141 	.data_read	= zcrypt_rng_data_read,
1142 };
1143 
zcrypt_rng_device_add(void)1144 static int zcrypt_rng_device_add(void)
1145 {
1146 	int rc = 0;
1147 
1148 	mutex_lock(&zcrypt_rng_mutex);
1149 	if (zcrypt_rng_device_count == 0) {
1150 		zcrypt_rng_buffer = (u32 *) get_zeroed_page(GFP_KERNEL);
1151 		if (!zcrypt_rng_buffer) {
1152 			rc = -ENOMEM;
1153 			goto out;
1154 		}
1155 		zcrypt_rng_buffer_index = 0;
1156 		rc = hwrng_register(&zcrypt_rng_dev);
1157 		if (rc)
1158 			goto out_free;
1159 		zcrypt_rng_device_count = 1;
1160 	} else
1161 		zcrypt_rng_device_count++;
1162 	mutex_unlock(&zcrypt_rng_mutex);
1163 	return 0;
1164 
1165 out_free:
1166 	free_page((unsigned long) zcrypt_rng_buffer);
1167 out:
1168 	mutex_unlock(&zcrypt_rng_mutex);
1169 	return rc;
1170 }
1171 
zcrypt_rng_device_remove(void)1172 static void zcrypt_rng_device_remove(void)
1173 {
1174 	mutex_lock(&zcrypt_rng_mutex);
1175 	zcrypt_rng_device_count--;
1176 	if (zcrypt_rng_device_count == 0) {
1177 		hwrng_unregister(&zcrypt_rng_dev);
1178 		free_page((unsigned long) zcrypt_rng_buffer);
1179 	}
1180 	mutex_unlock(&zcrypt_rng_mutex);
1181 }
1182 
1183 /**
1184  * zcrypt_api_init(): Module initialization.
1185  *
1186  * The module initialization code.
1187  */
zcrypt_api_init(void)1188 int __init zcrypt_api_init(void)
1189 {
1190 	int rc;
1191 
1192 	/* Register the request sprayer. */
1193 	rc = misc_register(&zcrypt_misc_device);
1194 	if (rc < 0)
1195 		goto out;
1196 
1197 	/* Set up the proc file system */
1198 	zcrypt_entry = proc_create("driver/z90crypt", 0644, NULL, &zcrypt_proc_fops);
1199 	if (!zcrypt_entry) {
1200 		rc = -ENOMEM;
1201 		goto out_misc;
1202 	}
1203 
1204 	return 0;
1205 
1206 out_misc:
1207 	misc_deregister(&zcrypt_misc_device);
1208 out:
1209 	return rc;
1210 }
1211 
1212 /**
1213  * zcrypt_api_exit(): Module termination.
1214  *
1215  * The module termination code.
1216  */
zcrypt_api_exit(void)1217 void zcrypt_api_exit(void)
1218 {
1219 	remove_proc_entry("driver/z90crypt", NULL);
1220 	misc_deregister(&zcrypt_misc_device);
1221 }
1222 
1223 module_init(zcrypt_api_init);
1224 module_exit(zcrypt_api_exit);
1225