[mirror_ubuntu-bionic-kernel.git] / arch / powerpc / crypto / crc32c-vpmsum_glue.c

#include <linux/crc32.h>
#include <crypto/internal/hash.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/cpufeature.h>
#include <asm/switch_to.h>

#define CHKSUM_BLOCK_SIZE	1
#define CHKSUM_DIGEST_SIZE	4

#define VMX_ALIGN		16
#define VMX_ALIGN_MASK		(VMX_ALIGN-1)

#define VECTOR_BREAKPOINT	512

u32 __crc32c_vpmsum(u32 crc, unsigned char const *p, size_t len);

static u32 crc32c_vpmsum(u32 crc, unsigned char const *p, size_t len)
{
	unsigned int prealign;
	unsigned int tail;

	if (len < (VECTOR_BREAKPOINT + VMX_ALIGN) || in_interrupt())
		return __crc32c_le(crc, p, len);

	if ((unsigned long)p & VMX_ALIGN_MASK) {
		prealign = VMX_ALIGN - ((unsigned long)p & VMX_ALIGN_MASK);
		crc = __crc32c_le(crc, p, prealign);
		len -= prealign;
		p += prealign;
	}

	if (len & ~VMX_ALIGN_MASK) {
		preempt_disable();
		pagefault_disable();
		enable_kernel_altivec();
		crc = __crc32c_vpmsum(crc, p, len & ~VMX_ALIGN_MASK);
		disable_kernel_altivec();
		pagefault_enable();
		preempt_enable();
	}

	tail = len & VMX_ALIGN_MASK;
	if (tail) {
		p += len & ~VMX_ALIGN_MASK;
		crc = __crc32c_le(crc, p, tail);
	}

	return crc;
}

static int crc32c_vpmsum_cra_init(struct crypto_tfm *tfm)
{
	u32 *key = crypto_tfm_ctx(tfm);

	*key = ~0;

	return 0;
}

/*
 * Setting the seed allows arbitrary accumulators and flexible XOR policy
 * If your algorithm starts with ~0, then XOR with ~0 before you set
 * the seed.
 */
static int crc32c_vpmsum_setkey(struct crypto_shash *hash, const u8 *key,
			       unsigned int keylen)
{
	u32 *mctx = crypto_shash_ctx(hash);

	if (keylen != sizeof(u32)) {
		crypto_shash_set_flags(hash, CRYPTO_TFM_RES_BAD_KEY_LEN);
		return -EINVAL;
	}
	*mctx = le32_to_cpup((__le32 *)key);
	return 0;
}

static int crc32c_vpmsum_init(struct shash_desc *desc)
{
	u32 *mctx = crypto_shash_ctx(desc->tfm);
	u32 *crcp = shash_desc_ctx(desc);

	*crcp = *mctx;

	return 0;
}

static int crc32c_vpmsum_update(struct shash_desc *desc, const u8 *data,
			       unsigned int len)
{
	u32 *crcp = shash_desc_ctx(desc);

	*crcp = crc32c_vpmsum(*crcp, data, len);

	return 0;
}

static int __crc32c_vpmsum_finup(u32 *crcp, const u8 *data, unsigned int len,
				u8 *out)
{
	*(__le32 *)out = ~cpu_to_le32(crc32c_vpmsum(*crcp, data, len));

	return 0;
}

static int crc32c_vpmsum_finup(struct shash_desc *desc, const u8 *data,
			      unsigned int len, u8 *out)
{
	return __crc32c_vpmsum_finup(shash_desc_ctx(desc), data, len, out);
}

static int crc32c_vpmsum_final(struct shash_desc *desc, u8 *out)
{
	u32 *crcp = shash_desc_ctx(desc);

	*(__le32 *)out = ~cpu_to_le32p(crcp);

	return 0;
}

static int crc32c_vpmsum_digest(struct shash_desc *desc, const u8 *data,
			       unsigned int len, u8 *out)
{
	return __crc32c_vpmsum_finup(crypto_shash_ctx(desc->tfm), data, len,
				     out);
}

static struct shash_alg alg = {
	.setkey		= crc32c_vpmsum_setkey,
	.init		= crc32c_vpmsum_init,
	.update		= crc32c_vpmsum_update,
	.final		= crc32c_vpmsum_final,
	.finup		= crc32c_vpmsum_finup,
	.digest		= crc32c_vpmsum_digest,
	.descsize	= sizeof(u32),
	.digestsize	= CHKSUM_DIGEST_SIZE,
	.base		= {
		.cra_name		= "crc32c",
		.cra_driver_name	= "crc32c-vpmsum",
		.cra_priority		= 200,
		.cra_flags		= CRYPTO_ALG_OPTIONAL_KEY,
		.cra_blocksize		= CHKSUM_BLOCK_SIZE,
		.cra_ctxsize		= sizeof(u32),
		.cra_module		= THIS_MODULE,
		.cra_init		= crc32c_vpmsum_cra_init,
	}
};

static int __init crc32c_vpmsum_mod_init(void)
{
	if (!cpu_has_feature(CPU_FTR_ARCH_207S))
		return -ENODEV;

	return crypto_register_shash(&alg);
}

static void __exit crc32c_vpmsum_mod_fini(void)
{
	crypto_unregister_shash(&alg);
}

module_cpu_feature_match(PPC_MODULE_FEATURE_VEC_CRYPTO, crc32c_vpmsum_mod_init);
module_exit(crc32c_vpmsum_mod_fini);

MODULE_AUTHOR("Anton Blanchard <anton@samba.org>");
MODULE_DESCRIPTION("CRC32C using vector polynomial multiply-sum instructions");
MODULE_LICENSE("GPL");
MODULE_ALIAS_CRYPTO("crc32c");
MODULE_ALIAS_CRYPTO("crc32c-vpmsum");
Commit	Line	Data
6dd7a82c AB	1	#include <linux/crc32.h>
	2	#include <crypto/internal/hash.h>
	3	#include <linux/init.h>
	4	#include <linux/module.h>
	5	#include <linux/string.h>
	6	#include <linux/kernel.h>
d2cf5be0	7	#include <linux/cpufeature.h>
6dd7a82c AB	8	#include <asm/switch_to.h>
	9
	10	#define CHKSUM_BLOCK_SIZE 1
	11	#define CHKSUM_DIGEST_SIZE 4
	12
	13	#define VMX_ALIGN 16
	14	#define VMX_ALIGN_MASK (VMX_ALIGN-1)
	15
	16	#define VECTOR_BREAKPOINT 512
	17
	18	u32 __crc32c_vpmsum(u32 crc, unsigned char const *p, size_t len);
	19
	20	static u32 crc32c_vpmsum(u32 crc, unsigned char const *p, size_t len)
	21	{
	22	unsigned int prealign;
	23	unsigned int tail;
	24
	25	if (len < (VECTOR_BREAKPOINT + VMX_ALIGN) \|\| in_interrupt())
	26	return __crc32c_le(crc, p, len);
	27
	28	if ((unsigned long)p & VMX_ALIGN_MASK) {
	29	prealign = VMX_ALIGN - ((unsigned long)p & VMX_ALIGN_MASK);
	30	crc = __crc32c_le(crc, p, prealign);
	31	len -= prealign;
	32	p += prealign;
	33	}
	34
	35	if (len & ~VMX_ALIGN_MASK) {
4749228f	36	preempt_disable();
6dd7a82c AB	37	pagefault_disable();
	38	enable_kernel_altivec();
	39	crc = __crc32c_vpmsum(crc, p, len & ~VMX_ALIGN_MASK);
4749228f	40	disable_kernel_altivec();
6dd7a82c	41	pagefault_enable();
4749228f	42	preempt_enable();
6dd7a82c AB	43	}
	44
	45	tail = len & VMX_ALIGN_MASK;
	46	if (tail) {
	47	p += len & ~VMX_ALIGN_MASK;
	48	crc = __crc32c_le(crc, p, tail);
	49	}
	50
	51	return crc;
	52	}
	53
	54	static int crc32c_vpmsum_cra_init(struct crypto_tfm *tfm)
	55	{
	56	u32 *key = crypto_tfm_ctx(tfm);
	57
aa2be9b3	58	*key = ~0;
6dd7a82c AB	59
	60	return 0;
	61	}
	62
	63	/*
	64	* Setting the seed allows arbitrary accumulators and flexible XOR policy
	65	* If your algorithm starts with ~0, then XOR with ~0 before you set
	66	* the seed.
	67	*/
	68	static int crc32c_vpmsum_setkey(struct crypto_shash hash, const u8 key,
	69	unsigned int keylen)
	70	{
	71	u32 *mctx = crypto_shash_ctx(hash);
	72
	73	if (keylen != sizeof(u32)) {
	74	crypto_shash_set_flags(hash, CRYPTO_TFM_RES_BAD_KEY_LEN);
	75	return -EINVAL;
	76	}
	77	mctx = le32_to_cpup((__le32 )key);
	78	return 0;
	79	}
	80
	81	static int crc32c_vpmsum_init(struct shash_desc *desc)
	82	{
	83	u32 *mctx = crypto_shash_ctx(desc->tfm);
	84	u32 *crcp = shash_desc_ctx(desc);
	85
	86	crcp = mctx;
	87
	88	return 0;
	89	}
	90
	91	static int crc32c_vpmsum_update(struct shash_desc desc, const u8 data,
	92	unsigned int len)
	93	{
	94	u32 *crcp = shash_desc_ctx(desc);
	95
	96	crcp = crc32c_vpmsum(crcp, data, len);
	97
	98	return 0;
	99	}
	100
	101	static int __crc32c_vpmsum_finup(u32 crcp, const u8 data, unsigned int len,
	102	u8 *out)
	103	{
	104	(__le32 )out = ~cpu_to_le32(crc32c_vpmsum(*crcp, data, len));
	105
	106	return 0;
	107	}
	108
	109	static int crc32c_vpmsum_finup(struct shash_desc desc, const u8 data,
	110	unsigned int len, u8 *out)
	111	{
	112	return __crc32c_vpmsum_finup(shash_desc_ctx(desc), data, len, out);
	113	}
	114
	115	static int crc32c_vpmsum_final(struct shash_desc desc, u8 out)
	116	{
	117	u32 *crcp = shash_desc_ctx(desc);
	118
	119	(__le32 )out = ~cpu_to_le32p(crcp);
	120
	121	return 0;
	122	}
123
124	static int crc32c_vpmsum_digest(struct shash_desc desc, const u8 data,
125	unsigned int len, u8 *out)
126	{
127	return __crc32c_vpmsum_finup(crypto_shash_ctx(desc->tfm), data, len,
128	out);
129	}
130
131	static struct shash_alg alg = {
132	.setkey = crc32c_vpmsum_setkey,
133	.init = crc32c_vpmsum_init,
134	.update = crc32c_vpmsum_update,
135	.final = crc32c_vpmsum_final,
136	.finup = crc32c_vpmsum_finup,
137	.digest = crc32c_vpmsum_digest,
138	.descsize = sizeof(u32),
139	.digestsize = CHKSUM_DIGEST_SIZE,
140	.base = {
141	.cra_name = "crc32c",
142	.cra_driver_name = "crc32c-vpmsum",
143	.cra_priority = 200,
b5c690bf	144	.cra_flags = CRYPTO_ALG_OPTIONAL_KEY,
6dd7a82c AB	145	.cra_blocksize = CHKSUM_BLOCK_SIZE,
	146	.cra_ctxsize = sizeof(u32),
	147	.cra_module = THIS_MODULE,
	148	.cra_init = crc32c_vpmsum_cra_init,
	149	}
	150	};
	151
	152	static int __init crc32c_vpmsum_mod_init(void)
	153	{
	154	if (!cpu_has_feature(CPU_FTR_ARCH_207S))
	155	return -ENODEV;
	156
	157	return crypto_register_shash(&alg);
	158	}
	159
	160	static void __exit crc32c_vpmsum_mod_fini(void)
	161	{
	162	crypto_unregister_shash(&alg);
	163	}
	164
d2cf5be0	165	module_cpu_feature_match(PPC_MODULE_FEATURE_VEC_CRYPTO, crc32c_vpmsum_mod_init);
6dd7a82c AB	166	module_exit(crc32c_vpmsum_mod_fini);
	167
	168	MODULE_AUTHOR("Anton Blanchard <anton@samba.org>");
	169	MODULE_DESCRIPTION("CRC32C using vector polynomial multiply-sum instructions");
	170	MODULE_LICENSE("GPL");
	171	MODULE_ALIAS_CRYPTO("crc32c");
	172	MODULE_ALIAS_CRYPTO("crc32c-vpmsum");