xref: /linux/drivers/crypto/nx/nx.c (revision 95e9fd10f06cb5642028b6b851e32b8c8afb4571)
1 /**
2  * Routines supporting the Power 7+ Nest Accelerators driver
3  *
4  * Copyright (C) 2011-2012 International Business Machines Inc.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; version 2 only.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
18  *
19  * Author: Kent Yoder <yoder1@us.ibm.com>
20  */
21 
22 #include <crypto/internal/hash.h>
23 #include <crypto/hash.h>
24 #include <crypto/aes.h>
25 #include <crypto/sha.h>
26 #include <crypto/algapi.h>
27 #include <crypto/scatterwalk.h>
28 #include <linux/module.h>
29 #include <linux/moduleparam.h>
30 #include <linux/types.h>
31 #include <linux/mm.h>
32 #include <linux/crypto.h>
33 #include <linux/scatterlist.h>
34 #include <linux/device.h>
35 #include <linux/of.h>
36 #include <asm/pSeries_reconfig.h>
37 #include <asm/abs_addr.h>
38 #include <asm/hvcall.h>
39 #include <asm/vio.h>
40 
41 #include "nx_csbcpb.h"
42 #include "nx.h"
43 
44 
45 /**
46  * nx_hcall_sync - make an H_COP_OP hcall for the passed in op structure
47  *
48  * @nx_ctx: the crypto context handle
49  * @op: PFO operation struct to pass in
50  * @may_sleep: flag indicating the request can sleep
51  *
52  * Make the hcall, retrying while the hardware is busy. If we cannot yield
53  * the thread, limit the number of retries to 10 here.
54  */
55 int nx_hcall_sync(struct nx_crypto_ctx *nx_ctx,
56 		  struct vio_pfo_op    *op,
57 		  u32                   may_sleep)
58 {
59 	int rc, retries = 10;
60 	struct vio_dev *viodev = nx_driver.viodev;
61 
62 	atomic_inc(&(nx_ctx->stats->sync_ops));
63 
64 	do {
65 		rc = vio_h_cop_sync(viodev, op);
66 	} while ((rc == -EBUSY && !may_sleep && retries--) ||
67 	         (rc == -EBUSY && may_sleep && cond_resched()));
68 
69 	if (rc) {
70 		dev_dbg(&viodev->dev, "vio_h_cop_sync failed: rc: %d "
71 			"hcall rc: %ld\n", rc, op->hcall_err);
72 		atomic_inc(&(nx_ctx->stats->errors));
73 		atomic_set(&(nx_ctx->stats->last_error), op->hcall_err);
74 		atomic_set(&(nx_ctx->stats->last_error_pid), current->pid);
75 	}
76 
77 	return rc;
78 }
79 
80 /**
81  * nx_build_sg_list - build an NX scatter list describing a single  buffer
82  *
83  * @sg_head: pointer to the first scatter list element to build
84  * @start_addr: pointer to the linear buffer
85  * @len: length of the data at @start_addr
86  * @sgmax: the largest number of scatter list elements we're allowed to create
87  *
88  * This function will start writing nx_sg elements at @sg_head and keep
89  * writing them until all of the data from @start_addr is described or
90  * until sgmax elements have been written. Scatter list elements will be
91  * created such that none of the elements describes a buffer that crosses a 4K
92  * boundary.
93  */
94 struct nx_sg *nx_build_sg_list(struct nx_sg *sg_head,
95 			       u8           *start_addr,
96 			       unsigned int  len,
97 			       u32           sgmax)
98 {
99 	unsigned int sg_len = 0;
100 	struct nx_sg *sg;
101 	u64 sg_addr = (u64)start_addr;
102 	u64 end_addr;
103 
104 	/* determine the start and end for this address range - slightly
105 	 * different if this is in VMALLOC_REGION */
106 	if (is_vmalloc_addr(start_addr))
107 		sg_addr = phys_to_abs(page_to_phys(vmalloc_to_page(start_addr)))
108 			  + offset_in_page(sg_addr);
109 	else
110 		sg_addr = virt_to_abs(sg_addr);
111 
112 	end_addr = sg_addr + len;
113 
114 	/* each iteration will write one struct nx_sg element and add the
115 	 * length of data described by that element to sg_len. Once @len bytes
116 	 * have been described (or @sgmax elements have been written), the
117 	 * loop ends. min_t is used to ensure @end_addr falls on the same page
118 	 * as sg_addr, if not, we need to create another nx_sg element for the
119 	 * data on the next page */
120 	for (sg = sg_head; sg_len < len; sg++) {
121 		sg->addr = sg_addr;
122 		sg_addr = min_t(u64, NX_PAGE_NUM(sg_addr + NX_PAGE_SIZE), end_addr);
123 		sg->len = sg_addr - sg->addr;
124 		sg_len += sg->len;
125 
126 		if ((sg - sg_head) == sgmax) {
127 			pr_err("nx: scatter/gather list overflow, pid: %d\n",
128 			       current->pid);
129 			return NULL;
130 		}
131 	}
132 
133 	/* return the moved sg_head pointer */
134 	return sg;
135 }
136 
137 /**
138  * nx_walk_and_build - walk a linux scatterlist and build an nx scatterlist
139  *
140  * @nx_dst: pointer to the first nx_sg element to write
141  * @sglen: max number of nx_sg entries we're allowed to write
142  * @sg_src: pointer to the source linux scatterlist to walk
143  * @start: number of bytes to fast-forward past at the beginning of @sg_src
144  * @src_len: number of bytes to walk in @sg_src
145  */
146 struct nx_sg *nx_walk_and_build(struct nx_sg       *nx_dst,
147 				unsigned int        sglen,
148 				struct scatterlist *sg_src,
149 				unsigned int        start,
150 				unsigned int        src_len)
151 {
152 	struct scatter_walk walk;
153 	struct nx_sg *nx_sg = nx_dst;
154 	unsigned int n, offset = 0, len = src_len;
155 	char *dst;
156 
157 	/* we need to fast forward through @start bytes first */
158 	for (;;) {
159 		scatterwalk_start(&walk, sg_src);
160 
161 		if (start < offset + sg_src->length)
162 			break;
163 
164 		offset += sg_src->length;
165 		sg_src = scatterwalk_sg_next(sg_src);
166 	}
167 
168 	/* start - offset is the number of bytes to advance in the scatterlist
169 	 * element we're currently looking at */
170 	scatterwalk_advance(&walk, start - offset);
171 
172 	while (len && nx_sg) {
173 		n = scatterwalk_clamp(&walk, len);
174 		if (!n) {
175 			scatterwalk_start(&walk, sg_next(walk.sg));
176 			n = scatterwalk_clamp(&walk, len);
177 		}
178 		dst = scatterwalk_map(&walk);
179 
180 		nx_sg = nx_build_sg_list(nx_sg, dst, n, sglen);
181 		len -= n;
182 
183 		scatterwalk_unmap(dst);
184 		scatterwalk_advance(&walk, n);
185 		scatterwalk_done(&walk, SCATTERWALK_FROM_SG, len);
186 	}
187 
188 	/* return the moved destination pointer */
189 	return nx_sg;
190 }
191 
192 /**
193  * nx_build_sg_lists - walk the input scatterlists and build arrays of NX
194  *                     scatterlists based on them.
195  *
196  * @nx_ctx: NX crypto context for the lists we're building
197  * @desc: the block cipher descriptor for the operation
198  * @dst: destination scatterlist
199  * @src: source scatterlist
200  * @nbytes: length of data described in the scatterlists
201  * @iv: destination for the iv data, if the algorithm requires it
202  *
203  * This is common code shared by all the AES algorithms. It uses the block
204  * cipher walk routines to traverse input and output scatterlists, building
205  * corresponding NX scatterlists
206  */
207 int nx_build_sg_lists(struct nx_crypto_ctx  *nx_ctx,
208 		      struct blkcipher_desc *desc,
209 		      struct scatterlist    *dst,
210 		      struct scatterlist    *src,
211 		      unsigned int           nbytes,
212 		      u8                    *iv)
213 {
214 	struct nx_sg *nx_insg = nx_ctx->in_sg;
215 	struct nx_sg *nx_outsg = nx_ctx->out_sg;
216 	struct blkcipher_walk walk;
217 	int rc;
218 
219 	blkcipher_walk_init(&walk, dst, src, nbytes);
220 	rc = blkcipher_walk_virt_block(desc, &walk, AES_BLOCK_SIZE);
221 	if (rc)
222 		goto out;
223 
224 	if (iv)
225 		memcpy(iv, walk.iv, AES_BLOCK_SIZE);
226 
227 	while (walk.nbytes) {
228 		nx_insg = nx_build_sg_list(nx_insg, walk.src.virt.addr,
229 					   walk.nbytes, nx_ctx->ap->sglen);
230 		nx_outsg = nx_build_sg_list(nx_outsg, walk.dst.virt.addr,
231 					    walk.nbytes, nx_ctx->ap->sglen);
232 
233 		rc = blkcipher_walk_done(desc, &walk, 0);
234 		if (rc)
235 			break;
236 	}
237 
238 	if (walk.nbytes) {
239 		nx_insg = nx_build_sg_list(nx_insg, walk.src.virt.addr,
240 					   walk.nbytes, nx_ctx->ap->sglen);
241 		nx_outsg = nx_build_sg_list(nx_outsg, walk.dst.virt.addr,
242 					    walk.nbytes, nx_ctx->ap->sglen);
243 
244 		rc = 0;
245 	}
246 
247 	/* these lengths should be negative, which will indicate to phyp that
248 	 * the input and output parameters are scatterlists, not linear
249 	 * buffers */
250 	nx_ctx->op.inlen = (nx_ctx->in_sg - nx_insg) * sizeof(struct nx_sg);
251 	nx_ctx->op.outlen = (nx_ctx->out_sg - nx_outsg) * sizeof(struct nx_sg);
252 out:
253 	return rc;
254 }
255 
256 /**
257  * nx_ctx_init - initialize an nx_ctx's vio_pfo_op struct
258  *
259  * @nx_ctx: the nx context to initialize
260  * @function: the function code for the op
261  */
262 void nx_ctx_init(struct nx_crypto_ctx *nx_ctx, unsigned int function)
263 {
264 	memset(nx_ctx->kmem, 0, nx_ctx->kmem_len);
265 	nx_ctx->csbcpb->csb.valid |= NX_CSB_VALID_BIT;
266 
267 	nx_ctx->op.flags = function;
268 	nx_ctx->op.csbcpb = virt_to_abs(nx_ctx->csbcpb);
269 	nx_ctx->op.in = virt_to_abs(nx_ctx->in_sg);
270 	nx_ctx->op.out = virt_to_abs(nx_ctx->out_sg);
271 
272 	if (nx_ctx->csbcpb_aead) {
273 		nx_ctx->csbcpb_aead->csb.valid |= NX_CSB_VALID_BIT;
274 
275 		nx_ctx->op_aead.flags = function;
276 		nx_ctx->op_aead.csbcpb = virt_to_abs(nx_ctx->csbcpb_aead);
277 		nx_ctx->op_aead.in = virt_to_abs(nx_ctx->in_sg);
278 		nx_ctx->op_aead.out = virt_to_abs(nx_ctx->out_sg);
279 	}
280 }
281 
282 static void nx_of_update_status(struct device   *dev,
283 			       struct property *p,
284 			       struct nx_of    *props)
285 {
286 	if (!strncmp(p->value, "okay", p->length)) {
287 		props->status = NX_WAITING;
288 		props->flags |= NX_OF_FLAG_STATUS_SET;
289 	} else {
290 		dev_info(dev, "%s: status '%s' is not 'okay'\n", __func__,
291 			 (char *)p->value);
292 	}
293 }
294 
295 static void nx_of_update_sglen(struct device   *dev,
296 			       struct property *p,
297 			       struct nx_of    *props)
298 {
299 	if (p->length != sizeof(props->max_sg_len)) {
300 		dev_err(dev, "%s: unexpected format for "
301 			"ibm,max-sg-len property\n", __func__);
302 		dev_dbg(dev, "%s: ibm,max-sg-len is %d bytes "
303 			"long, expected %zd bytes\n", __func__,
304 			p->length, sizeof(props->max_sg_len));
305 		return;
306 	}
307 
308 	props->max_sg_len = *(u32 *)p->value;
309 	props->flags |= NX_OF_FLAG_MAXSGLEN_SET;
310 }
311 
312 static void nx_of_update_msc(struct device   *dev,
313 			     struct property *p,
314 			     struct nx_of    *props)
315 {
316 	struct msc_triplet *trip;
317 	struct max_sync_cop *msc;
318 	unsigned int bytes_so_far, i, lenp;
319 
320 	msc = (struct max_sync_cop *)p->value;
321 	lenp = p->length;
322 
323 	/* You can't tell if the data read in for this property is sane by its
324 	 * size alone. This is because there are sizes embedded in the data
325 	 * structure. The best we can do is check lengths as we parse and bail
326 	 * as soon as a length error is detected. */
327 	bytes_so_far = 0;
328 
329 	while ((bytes_so_far + sizeof(struct max_sync_cop)) <= lenp) {
330 		bytes_so_far += sizeof(struct max_sync_cop);
331 
332 		trip = msc->trip;
333 
334 		for (i = 0;
335 		     ((bytes_so_far + sizeof(struct msc_triplet)) <= lenp) &&
336 		     i < msc->triplets;
337 		     i++) {
338 			if (msc->fc > NX_MAX_FC || msc->mode > NX_MAX_MODE) {
339 				dev_err(dev, "unknown function code/mode "
340 					"combo: %d/%d (ignored)\n", msc->fc,
341 					msc->mode);
342 				goto next_loop;
343 			}
344 
345 			switch (trip->keybitlen) {
346 			case 128:
347 			case 160:
348 				props->ap[msc->fc][msc->mode][0].databytelen =
349 					trip->databytelen;
350 				props->ap[msc->fc][msc->mode][0].sglen =
351 					trip->sglen;
352 				break;
353 			case 192:
354 				props->ap[msc->fc][msc->mode][1].databytelen =
355 					trip->databytelen;
356 				props->ap[msc->fc][msc->mode][1].sglen =
357 					trip->sglen;
358 				break;
359 			case 256:
360 				if (msc->fc == NX_FC_AES) {
361 					props->ap[msc->fc][msc->mode][2].
362 						databytelen = trip->databytelen;
363 					props->ap[msc->fc][msc->mode][2].sglen =
364 						trip->sglen;
365 				} else if (msc->fc == NX_FC_AES_HMAC ||
366 					   msc->fc == NX_FC_SHA) {
367 					props->ap[msc->fc][msc->mode][1].
368 						databytelen = trip->databytelen;
369 					props->ap[msc->fc][msc->mode][1].sglen =
370 						trip->sglen;
371 				} else {
372 					dev_warn(dev, "unknown function "
373 						"code/key bit len combo"
374 						": (%u/256)\n", msc->fc);
375 				}
376 				break;
377 			case 512:
378 				props->ap[msc->fc][msc->mode][2].databytelen =
379 					trip->databytelen;
380 				props->ap[msc->fc][msc->mode][2].sglen =
381 					trip->sglen;
382 				break;
383 			default:
384 				dev_warn(dev, "unknown function code/key bit "
385 					 "len combo: (%u/%u)\n", msc->fc,
386 					 trip->keybitlen);
387 				break;
388 			}
389 next_loop:
390 			bytes_so_far += sizeof(struct msc_triplet);
391 			trip++;
392 		}
393 
394 		msc = (struct max_sync_cop *)trip;
395 	}
396 
397 	props->flags |= NX_OF_FLAG_MAXSYNCCOP_SET;
398 }
399 
400 /**
401  * nx_of_init - read openFirmware values from the device tree
402  *
403  * @dev: device handle
404  * @props: pointer to struct to hold the properties values
405  *
406  * Called once at driver probe time, this function will read out the
407  * openFirmware properties we use at runtime. If all the OF properties are
408  * acceptable, when we exit this function props->flags will indicate that
409  * we're ready to register our crypto algorithms.
410  */
411 static void nx_of_init(struct device *dev, struct nx_of *props)
412 {
413 	struct device_node *base_node = dev->of_node;
414 	struct property *p;
415 
416 	p = of_find_property(base_node, "status", NULL);
417 	if (!p)
418 		dev_info(dev, "%s: property 'status' not found\n", __func__);
419 	else
420 		nx_of_update_status(dev, p, props);
421 
422 	p = of_find_property(base_node, "ibm,max-sg-len", NULL);
423 	if (!p)
424 		dev_info(dev, "%s: property 'ibm,max-sg-len' not found\n",
425 			 __func__);
426 	else
427 		nx_of_update_sglen(dev, p, props);
428 
429 	p = of_find_property(base_node, "ibm,max-sync-cop", NULL);
430 	if (!p)
431 		dev_info(dev, "%s: property 'ibm,max-sync-cop' not found\n",
432 			 __func__);
433 	else
434 		nx_of_update_msc(dev, p, props);
435 }
436 
437 /**
438  * nx_register_algs - register algorithms with the crypto API
439  *
440  * Called from nx_probe()
441  *
442  * If all OF properties are in an acceptable state, the driver flags will
443  * indicate that we're ready and we'll create our debugfs files and register
444  * out crypto algorithms.
445  */
446 static int nx_register_algs(void)
447 {
448 	int rc = -1;
449 
450 	if (nx_driver.of.flags != NX_OF_FLAG_MASK_READY)
451 		goto out;
452 
453 	memset(&nx_driver.stats, 0, sizeof(struct nx_stats));
454 
455 	rc = NX_DEBUGFS_INIT(&nx_driver);
456 	if (rc)
457 		goto out;
458 
459 	rc = crypto_register_alg(&nx_ecb_aes_alg);
460 	if (rc)
461 		goto out;
462 
463 	rc = crypto_register_alg(&nx_cbc_aes_alg);
464 	if (rc)
465 		goto out_unreg_ecb;
466 
467 	rc = crypto_register_alg(&nx_ctr_aes_alg);
468 	if (rc)
469 		goto out_unreg_cbc;
470 
471 	rc = crypto_register_alg(&nx_ctr3686_aes_alg);
472 	if (rc)
473 		goto out_unreg_ctr;
474 
475 	rc = crypto_register_alg(&nx_gcm_aes_alg);
476 	if (rc)
477 		goto out_unreg_ctr3686;
478 
479 	rc = crypto_register_alg(&nx_gcm4106_aes_alg);
480 	if (rc)
481 		goto out_unreg_gcm;
482 
483 	rc = crypto_register_alg(&nx_ccm_aes_alg);
484 	if (rc)
485 		goto out_unreg_gcm4106;
486 
487 	rc = crypto_register_alg(&nx_ccm4309_aes_alg);
488 	if (rc)
489 		goto out_unreg_ccm;
490 
491 	rc = crypto_register_shash(&nx_shash_sha256_alg);
492 	if (rc)
493 		goto out_unreg_ccm4309;
494 
495 	rc = crypto_register_shash(&nx_shash_sha512_alg);
496 	if (rc)
497 		goto out_unreg_s256;
498 
499 	rc = crypto_register_shash(&nx_shash_aes_xcbc_alg);
500 	if (rc)
501 		goto out_unreg_s512;
502 
503 	nx_driver.of.status = NX_OKAY;
504 
505 	goto out;
506 
507 out_unreg_s512:
508 	crypto_unregister_shash(&nx_shash_sha512_alg);
509 out_unreg_s256:
510 	crypto_unregister_shash(&nx_shash_sha256_alg);
511 out_unreg_ccm4309:
512 	crypto_unregister_alg(&nx_ccm4309_aes_alg);
513 out_unreg_ccm:
514 	crypto_unregister_alg(&nx_ccm_aes_alg);
515 out_unreg_gcm4106:
516 	crypto_unregister_alg(&nx_gcm4106_aes_alg);
517 out_unreg_gcm:
518 	crypto_unregister_alg(&nx_gcm_aes_alg);
519 out_unreg_ctr3686:
520 	crypto_unregister_alg(&nx_ctr3686_aes_alg);
521 out_unreg_ctr:
522 	crypto_unregister_alg(&nx_ctr_aes_alg);
523 out_unreg_cbc:
524 	crypto_unregister_alg(&nx_cbc_aes_alg);
525 out_unreg_ecb:
526 	crypto_unregister_alg(&nx_ecb_aes_alg);
527 out:
528 	return rc;
529 }
530 
531 /**
532  * nx_crypto_ctx_init - create and initialize a crypto api context
533  *
534  * @nx_ctx: the crypto api context
535  * @fc: function code for the context
536  * @mode: the function code specific mode for this context
537  */
538 static int nx_crypto_ctx_init(struct nx_crypto_ctx *nx_ctx, u32 fc, u32 mode)
539 {
540 	if (nx_driver.of.status != NX_OKAY) {
541 		pr_err("Attempt to initialize NX crypto context while device "
542 		       "is not available!\n");
543 		return -ENODEV;
544 	}
545 
546 	/* we need an extra page for csbcpb_aead for these modes */
547 	if (mode == NX_MODE_AES_GCM || mode == NX_MODE_AES_CCM)
548 		nx_ctx->kmem_len = (4 * NX_PAGE_SIZE) +
549 				   sizeof(struct nx_csbcpb);
550 	else
551 		nx_ctx->kmem_len = (3 * NX_PAGE_SIZE) +
552 				   sizeof(struct nx_csbcpb);
553 
554 	nx_ctx->kmem = kmalloc(nx_ctx->kmem_len, GFP_KERNEL);
555 	if (!nx_ctx->kmem)
556 		return -ENOMEM;
557 
558 	/* the csbcpb and scatterlists must be 4K aligned pages */
559 	nx_ctx->csbcpb = (struct nx_csbcpb *)(round_up((u64)nx_ctx->kmem,
560 						       (u64)NX_PAGE_SIZE));
561 	nx_ctx->in_sg = (struct nx_sg *)((u8 *)nx_ctx->csbcpb + NX_PAGE_SIZE);
562 	nx_ctx->out_sg = (struct nx_sg *)((u8 *)nx_ctx->in_sg + NX_PAGE_SIZE);
563 
564 	if (mode == NX_MODE_AES_GCM || mode == NX_MODE_AES_CCM)
565 		nx_ctx->csbcpb_aead =
566 			(struct nx_csbcpb *)((u8 *)nx_ctx->out_sg +
567 					     NX_PAGE_SIZE);
568 
569 	/* give each context a pointer to global stats and their OF
570 	 * properties */
571 	nx_ctx->stats = &nx_driver.stats;
572 	memcpy(nx_ctx->props, nx_driver.of.ap[fc][mode],
573 	       sizeof(struct alg_props) * 3);
574 
575 	return 0;
576 }
577 
578 /* entry points from the crypto tfm initializers */
579 int nx_crypto_ctx_aes_ccm_init(struct crypto_tfm *tfm)
580 {
581 	return nx_crypto_ctx_init(crypto_tfm_ctx(tfm), NX_FC_AES,
582 				  NX_MODE_AES_CCM);
583 }
584 
585 int nx_crypto_ctx_aes_gcm_init(struct crypto_tfm *tfm)
586 {
587 	return nx_crypto_ctx_init(crypto_tfm_ctx(tfm), NX_FC_AES,
588 				  NX_MODE_AES_GCM);
589 }
590 
591 int nx_crypto_ctx_aes_ctr_init(struct crypto_tfm *tfm)
592 {
593 	return nx_crypto_ctx_init(crypto_tfm_ctx(tfm), NX_FC_AES,
594 				  NX_MODE_AES_CTR);
595 }
596 
597 int nx_crypto_ctx_aes_cbc_init(struct crypto_tfm *tfm)
598 {
599 	return nx_crypto_ctx_init(crypto_tfm_ctx(tfm), NX_FC_AES,
600 				  NX_MODE_AES_CBC);
601 }
602 
603 int nx_crypto_ctx_aes_ecb_init(struct crypto_tfm *tfm)
604 {
605 	return nx_crypto_ctx_init(crypto_tfm_ctx(tfm), NX_FC_AES,
606 				  NX_MODE_AES_ECB);
607 }
608 
609 int nx_crypto_ctx_sha_init(struct crypto_tfm *tfm)
610 {
611 	return nx_crypto_ctx_init(crypto_tfm_ctx(tfm), NX_FC_SHA, NX_MODE_SHA);
612 }
613 
614 int nx_crypto_ctx_aes_xcbc_init(struct crypto_tfm *tfm)
615 {
616 	return nx_crypto_ctx_init(crypto_tfm_ctx(tfm), NX_FC_AES,
617 				  NX_MODE_AES_XCBC_MAC);
618 }
619 
620 /**
621  * nx_crypto_ctx_exit - destroy a crypto api context
622  *
623  * @tfm: the crypto transform pointer for the context
624  *
625  * As crypto API contexts are destroyed, this exit hook is called to free the
626  * memory associated with it.
627  */
628 void nx_crypto_ctx_exit(struct crypto_tfm *tfm)
629 {
630 	struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(tfm);
631 
632 	kzfree(nx_ctx->kmem);
633 	nx_ctx->csbcpb = NULL;
634 	nx_ctx->csbcpb_aead = NULL;
635 	nx_ctx->in_sg = NULL;
636 	nx_ctx->out_sg = NULL;
637 }
638 
639 static int __devinit nx_probe(struct vio_dev *viodev,
640 			      const struct vio_device_id *id)
641 {
642 	dev_dbg(&viodev->dev, "driver probed: %s resource id: 0x%x\n",
643 		viodev->name, viodev->resource_id);
644 
645 	if (nx_driver.viodev) {
646 		dev_err(&viodev->dev, "%s: Attempt to register more than one "
647 			"instance of the hardware\n", __func__);
648 		return -EINVAL;
649 	}
650 
651 	nx_driver.viodev = viodev;
652 
653 	nx_of_init(&viodev->dev, &nx_driver.of);
654 
655 	return nx_register_algs();
656 }
657 
658 static int __devexit nx_remove(struct vio_dev *viodev)
659 {
660 	dev_dbg(&viodev->dev, "entering nx_remove for UA 0x%x\n",
661 		viodev->unit_address);
662 
663 	if (nx_driver.of.status == NX_OKAY) {
664 		NX_DEBUGFS_FINI(&nx_driver);
665 
666 		crypto_unregister_alg(&nx_ccm_aes_alg);
667 		crypto_unregister_alg(&nx_ccm4309_aes_alg);
668 		crypto_unregister_alg(&nx_gcm_aes_alg);
669 		crypto_unregister_alg(&nx_gcm4106_aes_alg);
670 		crypto_unregister_alg(&nx_ctr_aes_alg);
671 		crypto_unregister_alg(&nx_ctr3686_aes_alg);
672 		crypto_unregister_alg(&nx_cbc_aes_alg);
673 		crypto_unregister_alg(&nx_ecb_aes_alg);
674 		crypto_unregister_shash(&nx_shash_sha256_alg);
675 		crypto_unregister_shash(&nx_shash_sha512_alg);
676 		crypto_unregister_shash(&nx_shash_aes_xcbc_alg);
677 	}
678 
679 	return 0;
680 }
681 
682 
683 /* module wide initialization/cleanup */
684 static int __init nx_init(void)
685 {
686 	return vio_register_driver(&nx_driver.viodriver);
687 }
688 
689 static void __exit nx_fini(void)
690 {
691 	vio_unregister_driver(&nx_driver.viodriver);
692 }
693 
694 static struct vio_device_id nx_crypto_driver_ids[] __devinitdata = {
695 	{ "ibm,sym-encryption-v1", "ibm,sym-encryption" },
696 	{ "", "" }
697 };
698 MODULE_DEVICE_TABLE(vio, nx_crypto_driver_ids);
699 
700 /* driver state structure */
701 struct nx_crypto_driver nx_driver = {
702 	.viodriver = {
703 		.id_table = nx_crypto_driver_ids,
704 		.probe = nx_probe,
705 		.remove = nx_remove,
706 		.name  = NX_NAME,
707 	},
708 };
709 
710 module_init(nx_init);
711 module_exit(nx_fini);
712 
713 MODULE_AUTHOR("Kent Yoder <yoder1@us.ibm.com>");
714 MODULE_DESCRIPTION(NX_STRING);
715 MODULE_LICENSE("GPL");
716 MODULE_VERSION(NX_VERSION);
717