[linux-2.6-block.git] / drivers / mtd / tests / mtd_nandecctest.c

#define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/list.h>
#include <linux/random.h>
#include <linux/string.h>
#include <linux/bitops.h>
#include <linux/slab.h>
#include <linux/mtd/nand_ecc.h>

#include "mtd_test.h"

/*
 * Test the implementation for software ECC
 *
 * No actual MTD device is needed, So we don't need to warry about losing
 * important data by human error.
 *
 * This covers possible patterns of corruption which can be reliably corrected
 * or detected.
 */

#if IS_ENABLED(CONFIG_MTD_NAND)

struct nand_ecc_test {
	const char *name;
	void (*prepare)(void *, void *, void *, void *, const size_t);
	int (*verify)(void *, void *, void *, const size_t);
};

/*
 * The reason for this __change_bit_le() instead of __change_bit() is to inject
 * bit error properly within the region which is not a multiple of
 * sizeof(unsigned long) on big-endian systems
 */
#ifdef __LITTLE_ENDIAN
#define __change_bit_le(nr, addr) __change_bit(nr, addr)
#elif defined(__BIG_ENDIAN)
#define __change_bit_le(nr, addr) \
		__change_bit((nr) ^ ((BITS_PER_LONG - 1) & ~0x7), addr)
#else
#error "Unknown byte order"
#endif

static void single_bit_error_data(void *error_data, void *correct_data,
				size_t size)
{
	unsigned int offset = prandom_u32() % (size * BITS_PER_BYTE);

	memcpy(error_data, correct_data, size);
	__change_bit_le(offset, error_data);
}

static void double_bit_error_data(void *error_data, void *correct_data,
				size_t size)
{
	unsigned int offset[2];

	offset[0] = prandom_u32() % (size * BITS_PER_BYTE);
	do {
		offset[1] = prandom_u32() % (size * BITS_PER_BYTE);
	} while (offset[0] == offset[1]);

	memcpy(error_data, correct_data, size);

	__change_bit_le(offset[0], error_data);
	__change_bit_le(offset[1], error_data);
}

static unsigned int random_ecc_bit(size_t size)
{
	unsigned int offset = prandom_u32() % (3 * BITS_PER_BYTE);

	if (size == 256) {
		/*
		 * Don't inject a bit error into the insignificant bits (16th
		 * and 17th bit) in ECC code for 256 byte data block
		 */
		while (offset == 16 || offset == 17)
			offset = prandom_u32() % (3 * BITS_PER_BYTE);
	}

	return offset;
}

static void single_bit_error_ecc(void *error_ecc, void *correct_ecc,
				size_t size)
{
	unsigned int offset = random_ecc_bit(size);

	memcpy(error_ecc, correct_ecc, 3);
	__change_bit_le(offset, error_ecc);
}

static void double_bit_error_ecc(void *error_ecc, void *correct_ecc,
				size_t size)
{
	unsigned int offset[2];

	offset[0] = random_ecc_bit(size);
	do {
		offset[1] = random_ecc_bit(size);
	} while (offset[0] == offset[1]);

	memcpy(error_ecc, correct_ecc, 3);
	__change_bit_le(offset[0], error_ecc);
	__change_bit_le(offset[1], error_ecc);
}

static void no_bit_error(void *error_data, void *error_ecc,
		void *correct_data, void *correct_ecc, const size_t size)
{
	memcpy(error_data, correct_data, size);
	memcpy(error_ecc, correct_ecc, 3);
}

static int no_bit_error_verify(void *error_data, void *error_ecc,
				void *correct_data, const size_t size)
{
	unsigned char calc_ecc[3];
	int ret;

	__nand_calculate_ecc(error_data, size, calc_ecc,
			     IS_ENABLED(CONFIG_MTD_NAND_ECC_SMC));
	ret = __nand_correct_data(error_data, error_ecc, calc_ecc, size,
				  IS_ENABLED(CONFIG_MTD_NAND_ECC_SMC));
	if (ret == 0 && !memcmp(correct_data, error_data, size))
		return 0;

	return -EINVAL;
}

static void single_bit_error_in_data(void *error_data, void *error_ecc,
		void *correct_data, void *correct_ecc, const size_t size)
{
	single_bit_error_data(error_data, correct_data, size);
	memcpy(error_ecc, correct_ecc, 3);
}

static void single_bit_error_in_ecc(void *error_data, void *error_ecc,
		void *correct_data, void *correct_ecc, const size_t size)
{
	memcpy(error_data, correct_data, size);
	single_bit_error_ecc(error_ecc, correct_ecc, size);
}

static int single_bit_error_correct(void *error_data, void *error_ecc,
				void *correct_data, const size_t size)
{
	unsigned char calc_ecc[3];
	int ret;

	__nand_calculate_ecc(error_data, size, calc_ecc,
			     IS_ENABLED(CONFIG_MTD_NAND_ECC_SMC));
	ret = __nand_correct_data(error_data, error_ecc, calc_ecc, size,
				  IS_ENABLED(CONFIG_MTD_NAND_ECC_SMC));
	if (ret == 1 && !memcmp(correct_data, error_data, size))
		return 0;

	return -EINVAL;
}

static void double_bit_error_in_data(void *error_data, void *error_ecc,
		void *correct_data, void *correct_ecc, const size_t size)
{
	double_bit_error_data(error_data, correct_data, size);
	memcpy(error_ecc, correct_ecc, 3);
}

static void single_bit_error_in_data_and_ecc(void *error_data, void *error_ecc,
		void *correct_data, void *correct_ecc, const size_t size)
{
	single_bit_error_data(error_data, correct_data, size);
	single_bit_error_ecc(error_ecc, correct_ecc, size);
}

static void double_bit_error_in_ecc(void *error_data, void *error_ecc,
		void *correct_data, void *correct_ecc, const size_t size)
{
	memcpy(error_data, correct_data, size);
	double_bit_error_ecc(error_ecc, correct_ecc, size);
}

static int double_bit_error_detect(void *error_data, void *error_ecc,
				void *correct_data, const size_t size)
{
	unsigned char calc_ecc[3];
	int ret;

	__nand_calculate_ecc(error_data, size, calc_ecc,
			     IS_ENABLED(CONFIG_MTD_NAND_ECC_SMC));
	ret = __nand_correct_data(error_data, error_ecc, calc_ecc, size,
				  IS_ENABLED(CONFIG_MTD_NAND_ECC_SMC));

	return (ret == -EBADMSG) ? 0 : -EINVAL;
}

static const struct nand_ecc_test nand_ecc_test[] = {
	{
		.name = "no-bit-error",
		.prepare = no_bit_error,
		.verify = no_bit_error_verify,
	},
	{
		.name = "single-bit-error-in-data-correct",
		.prepare = single_bit_error_in_data,
		.verify = single_bit_error_correct,
	},
	{
		.name = "single-bit-error-in-ecc-correct",
		.prepare = single_bit_error_in_ecc,
		.verify = single_bit_error_correct,
	},
	{
		.name = "double-bit-error-in-data-detect",
		.prepare = double_bit_error_in_data,
		.verify = double_bit_error_detect,
	},
	{
		.name = "single-bit-error-in-data-and-ecc-detect",
		.prepare = single_bit_error_in_data_and_ecc,
		.verify = double_bit_error_detect,
	},
	{
		.name = "double-bit-error-in-ecc-detect",
		.prepare = double_bit_error_in_ecc,
		.verify = double_bit_error_detect,
	},
};

static void dump_data_ecc(void *error_data, void *error_ecc, void *correct_data,
			void *correct_ecc, const size_t size)
{
	pr_info("hexdump of error data:\n");
	print_hex_dump(KERN_INFO, "", DUMP_PREFIX_OFFSET, 16, 4,
			error_data, size, false);
	print_hex_dump(KERN_INFO, "hexdump of error ecc: ",
			DUMP_PREFIX_NONE, 16, 1, error_ecc, 3, false);

	pr_info("hexdump of correct data:\n");
	print_hex_dump(KERN_INFO, "", DUMP_PREFIX_OFFSET, 16, 4,
			correct_data, size, false);
	print_hex_dump(KERN_INFO, "hexdump of correct ecc: ",
			DUMP_PREFIX_NONE, 16, 1, correct_ecc, 3, false);
}

static int nand_ecc_test_run(const size_t size)
{
	int i;
	int err = 0;
	void *error_data;
	void *error_ecc;
	void *correct_data;
	void *correct_ecc;

	error_data = kmalloc(size, GFP_KERNEL);
	error_ecc = kmalloc(3, GFP_KERNEL);
	correct_data = kmalloc(size, GFP_KERNEL);
	correct_ecc = kmalloc(3, GFP_KERNEL);

	if (!error_data || !error_ecc || !correct_data || !correct_ecc) {
		err = -ENOMEM;
		goto error;
	}

	prandom_bytes(correct_data, size);
	__nand_calculate_ecc(correct_data, size, correct_ecc,
			     IS_ENABLED(CONFIG_MTD_NAND_ECC_SMC));

	for (i = 0; i < ARRAY_SIZE(nand_ecc_test); i++) {
		nand_ecc_test[i].prepare(error_data, error_ecc,
				correct_data, correct_ecc, size);
		err = nand_ecc_test[i].verify(error_data, error_ecc,
						correct_data, size);

		if (err) {
			pr_err("not ok - %s-%zd\n",
				nand_ecc_test[i].name, size);
			dump_data_ecc(error_data, error_ecc,
				correct_data, correct_ecc, size);
			break;
		}
		pr_info("ok - %s-%zd\n",
			nand_ecc_test[i].name, size);

		err = mtdtest_relax();
		if (err)
			break;
	}
error:
	kfree(error_data);
	kfree(error_ecc);
	kfree(correct_data);
	kfree(correct_ecc);

	return err;
}

#else

static int nand_ecc_test_run(const size_t size)
{
	return 0;
}

#endif

static int __init ecc_test_init(void)
{
	int err;

	err = nand_ecc_test_run(256);
	if (err)
		return err;

	return nand_ecc_test_run(512);
}

static void __exit ecc_test_exit(void)
{
}

module_init(ecc_test_init);
module_exit(ecc_test_exit);

MODULE_DESCRIPTION("NAND ECC function test module");
MODULE_AUTHOR("Akinobu Mita");
MODULE_LICENSE("GPL");
Commit	Line	Data
b6489d97 VN	1	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
b6489d97 VN	2
7126bd8b AM	3	#include <linux/kernel.h>
	4	#include <linux/module.h>
	5	#include <linux/list.h>
7126bd8b AM	6	#include <linux/random.h>
	7	#include <linux/string.h>
	8	#include <linux/bitops.h>
1749c00f	9	#include <linux/slab.h>
7126bd8b AM	10	#include <linux/mtd/nand_ecc.h>
7126bd8b AM	11
2a6a28e7 RW	12	#include "mtd_test.h"
2a6a28e7 RW	13
6060fb42 AM	14	/*
	15	* Test the implementation for software ECC
	16	*
	17	* No actual MTD device is needed, So we don't need to warry about losing
	18	* important data by human error.
	19	*
	20	* This covers possible patterns of corruption which can be reliably corrected
	21	* or detected.
	22	*/
	23
7e8eb8ae	24	#if IS_ENABLED(CONFIG_MTD_NAND)
7126bd8b	25
6060fb42 AM	26	struct nand_ecc_test {
	27	const char *name;
	28	void (prepare)(void , void , void , void *, const size_t);
	29	int (verify)(void , void , void , const size_t);
	30	};
	31
c092b439 AM	32	/*
	33	* The reason for this __change_bit_le() instead of __change_bit() is to inject
	34	* bit error properly within the region which is not a multiple of
	35	* sizeof(unsigned long) on big-endian systems
	36	*/
	37	#ifdef __LITTLE_ENDIAN
	38	#define __change_bit_le(nr, addr) __change_bit(nr, addr)
	39	#elif defined(__BIG_ENDIAN)
	40	#define __change_bit_le(nr, addr) \
	41	__change_bit((nr) ^ ((BITS_PER_LONG - 1) & ~0x7), addr)
	42	#else
	43	#error "Unknown byte order"
	44	#endif
	45
6060fb42 AM	46	static void single_bit_error_data(void error_data, void correct_data,
6060fb42 AM	47	size_t size)
7126bd8b	48	{
aca662a3	49	unsigned int offset = prandom_u32() % (size * BITS_PER_BYTE);
7126bd8b	50
6060fb42 AM	51	memcpy(error_data, correct_data, size);
	52	__change_bit_le(offset, error_data);
	53	}
	54
6ed089c0 AM	55	static void double_bit_error_data(void error_data, void correct_data,
	56	size_t size)
	57	{
	58	unsigned int offset[2];
	59
aca662a3	60	offset[0] = prandom_u32() % (size * BITS_PER_BYTE);
6ed089c0	61	do {
aca662a3	62	offset[1] = prandom_u32() % (size * BITS_PER_BYTE);
6ed089c0 AM	63	} while (offset[0] == offset[1]);
	64
	65	memcpy(error_data, correct_data, size);
	66
	67	__change_bit_le(offset[0], error_data);
	68	__change_bit_le(offset[1], error_data);
	69	}
	70
200ab845 AM	71	static unsigned int random_ecc_bit(size_t size)
200ab845 AM	72	{
aca662a3	73	unsigned int offset = prandom_u32() % (3 * BITS_PER_BYTE);
200ab845 AM	74
	75	if (size == 256) {
	76	/*
	77	* Don't inject a bit error into the insignificant bits (16th
	78	* and 17th bit) in ECC code for 256 byte data block
	79	*/
	80	while (offset == 16 \|\| offset == 17)
aca662a3	81	offset = prandom_u32() % (3 * BITS_PER_BYTE);
200ab845 AM	82	}
	83
	84	return offset;
	85	}
	86
	87	static void single_bit_error_ecc(void error_ecc, void correct_ecc,
	88	size_t size)
	89	{
	90	unsigned int offset = random_ecc_bit(size);
	91
	92	memcpy(error_ecc, correct_ecc, 3);
	93	__change_bit_le(offset, error_ecc);
	94	}
	95
6ed089c0 AM	96	static void double_bit_error_ecc(void error_ecc, void correct_ecc,
	97	size_t size)
	98	{
	99	unsigned int offset[2];
	100
	101	offset[0] = random_ecc_bit(size);
	102	do {
	103	offset[1] = random_ecc_bit(size);
	104	} while (offset[0] == offset[1]);
	105
	106	memcpy(error_ecc, correct_ecc, 3);
	107	__change_bit_le(offset[0], error_ecc);
	108	__change_bit_le(offset[1], error_ecc);
	109	}
	110
ccaa6795 AM	111	static void no_bit_error(void error_data, void error_ecc,
	112	void correct_data, void correct_ecc, const size_t size)
	113	{
	114	memcpy(error_data, correct_data, size);
	115	memcpy(error_ecc, correct_ecc, 3);
	116	}
	117
	118	static int no_bit_error_verify(void error_data, void error_ecc,
	119	void *correct_data, const size_t size)
	120	{
	121	unsigned char calc_ecc[3];
	122	int ret;
	123
309600c1 BB	124	__nand_calculate_ecc(error_data, size, calc_ecc,
	125	IS_ENABLED(CONFIG_MTD_NAND_ECC_SMC));
	126	ret = __nand_correct_data(error_data, error_ecc, calc_ecc, size,
	127	IS_ENABLED(CONFIG_MTD_NAND_ECC_SMC));
ccaa6795 AM	128	if (ret == 0 && !memcmp(correct_data, error_data, size))
	129	return 0;
	130
	131	return -EINVAL;
	132	}
	133
6060fb42 AM	134	static void single_bit_error_in_data(void error_data, void error_ecc,
	135	void correct_data, void correct_ecc, const size_t size)
	136	{
	137	single_bit_error_data(error_data, correct_data, size);
	138	memcpy(error_ecc, correct_ecc, 3);
	139	}
	140
200ab845 AM	141	static void single_bit_error_in_ecc(void error_data, void error_ecc,
	142	void correct_data, void correct_ecc, const size_t size)
	143	{
	144	memcpy(error_data, correct_data, size);
	145	single_bit_error_ecc(error_ecc, correct_ecc, size);
	146	}
	147
6060fb42 AM	148	static int single_bit_error_correct(void error_data, void error_ecc,
	149	void *correct_data, const size_t size)
	150	{
	151	unsigned char calc_ecc[3];
	152	int ret;
	153
309600c1 BB	154	__nand_calculate_ecc(error_data, size, calc_ecc,
	155	IS_ENABLED(CONFIG_MTD_NAND_ECC_SMC));
	156	ret = __nand_correct_data(error_data, error_ecc, calc_ecc, size,
	157	IS_ENABLED(CONFIG_MTD_NAND_ECC_SMC));
6060fb42 AM	158	if (ret == 1 && !memcmp(correct_data, error_data, size))
	159	return 0;
	160
	161	return -EINVAL;
7126bd8b AM	162	}
7126bd8b AM	163
6ed089c0 AM	164	static void double_bit_error_in_data(void error_data, void error_ecc,
	165	void correct_data, void correct_ecc, const size_t size)
	166	{
	167	double_bit_error_data(error_data, correct_data, size);
	168	memcpy(error_ecc, correct_ecc, 3);
	169	}
	170
	171	static void single_bit_error_in_data_and_ecc(void error_data, void error_ecc,
	172	void correct_data, void correct_ecc, const size_t size)
	173	{
	174	single_bit_error_data(error_data, correct_data, size);
	175	single_bit_error_ecc(error_ecc, correct_ecc, size);
	176	}
	177
	178	static void double_bit_error_in_ecc(void error_data, void error_ecc,
	179	void correct_data, void correct_ecc, const size_t size)
	180	{
	181	memcpy(error_data, correct_data, size);
	182	double_bit_error_ecc(error_ecc, correct_ecc, size);
	183	}
	184
	185	static int double_bit_error_detect(void error_data, void error_ecc,
	186	void *correct_data, const size_t size)
	187	{
	188	unsigned char calc_ecc[3];
	189	int ret;
	190
309600c1 BB	191	__nand_calculate_ecc(error_data, size, calc_ecc,
	192	IS_ENABLED(CONFIG_MTD_NAND_ECC_SMC));
	193	ret = __nand_correct_data(error_data, error_ecc, calc_ecc, size,
	194	IS_ENABLED(CONFIG_MTD_NAND_ECC_SMC));
6ed089c0	195
c57753d4	196	return (ret == -EBADMSG) ? 0 : -EINVAL;
6ed089c0 AM	197	}
6ed089c0 AM	198
6060fb42	199	static const struct nand_ecc_test nand_ecc_test[] = {
ccaa6795 AM	200	{
	201	.name = "no-bit-error",
	202	.prepare = no_bit_error,
	203	.verify = no_bit_error_verify,
	204	},
6060fb42 AM	205	{
	206	.name = "single-bit-error-in-data-correct",
	207	.prepare = single_bit_error_in_data,
	208	.verify = single_bit_error_correct,
	209	},
200ab845 AM	210	{
	211	.name = "single-bit-error-in-ecc-correct",
	212	.prepare = single_bit_error_in_ecc,
	213	.verify = single_bit_error_correct,
	214	},
6ed089c0 AM	215	{
	216	.name = "double-bit-error-in-data-detect",
	217	.prepare = double_bit_error_in_data,
	218	.verify = double_bit_error_detect,
	219	},
	220	{
	221	.name = "single-bit-error-in-data-and-ecc-detect",
	222	.prepare = single_bit_error_in_data_and_ecc,
	223	.verify = double_bit_error_detect,
	224	},
	225	{
	226	.name = "double-bit-error-in-ecc-detect",
	227	.prepare = double_bit_error_in_ecc,
	228	.verify = double_bit_error_detect,
	229	},
6060fb42 AM	230	};
6060fb42 AM	231
c5b8384a AM	232	static void dump_data_ecc(void error_data, void error_ecc, void *correct_data,
	233	void *correct_ecc, const size_t size)
	234	{
	235	pr_info("hexdump of error data:\n");
	236	print_hex_dump(KERN_INFO, "", DUMP_PREFIX_OFFSET, 16, 4,
	237	error_data, size, false);
	238	print_hex_dump(KERN_INFO, "hexdump of error ecc: ",
	239	DUMP_PREFIX_NONE, 16, 1, error_ecc, 3, false);
	240
	241	pr_info("hexdump of correct data:\n");
	242	print_hex_dump(KERN_INFO, "", DUMP_PREFIX_OFFSET, 16, 4,
	243	correct_data, size, false);
	244	print_hex_dump(KERN_INFO, "hexdump of correct ecc: ",
	245	DUMP_PREFIX_NONE, 16, 1, correct_ecc, 3, false);
	246	}
	247
6060fb42	248	static int nand_ecc_test_run(const size_t size)
7126bd8b	249	{
6060fb42	250	int i;
1749c00f AM	251	int err = 0;
	252	void *error_data;
	253	void *error_ecc;
	254	void *correct_data;
	255	void *correct_ecc;
7126bd8b	256
1749c00f AM	257	error_data = kmalloc(size, GFP_KERNEL);
	258	error_ecc = kmalloc(3, GFP_KERNEL);
	259	correct_data = kmalloc(size, GFP_KERNEL);
	260	correct_ecc = kmalloc(3, GFP_KERNEL);
	261
	262	if (!error_data \|\| !error_ecc \|\| !correct_data \|\| !correct_ecc) {
	263	err = -ENOMEM;
	264	goto error;
	265	}
7126bd8b	266
459a86d8	267	prandom_bytes(correct_data, size);
309600c1 BB	268	__nand_calculate_ecc(correct_data, size, correct_ecc,
309600c1 BB	269	IS_ENABLED(CONFIG_MTD_NAND_ECC_SMC));
6060fb42 AM	270
	271	for (i = 0; i < ARRAY_SIZE(nand_ecc_test); i++) {
	272	nand_ecc_test[i].prepare(error_data, error_ecc,
	273	correct_data, correct_ecc, size);
	274	err = nand_ecc_test[i].verify(error_data, error_ecc,
	275	correct_data, size);
	276
	277	if (err) {
b6489d97	278	pr_err("not ok - %s-%zd\n",
6060fb42 AM	279	nand_ecc_test[i].name, size);
	280	dump_data_ecc(error_data, error_ecc,
	281	correct_data, correct_ecc, size);
	282	break;
	283	}
b6489d97	284	pr_info("ok - %s-%zd\n",
6060fb42	285	nand_ecc_test[i].name, size);
2a6a28e7 RW	286
	287	err = mtdtest_relax();
	288	if (err)
	289	break;
7126bd8b	290	}
1749c00f AM	291	error:
	292	kfree(error_data);
	293	kfree(error_ecc);
	294	kfree(correct_data);
	295	kfree(correct_ecc);
	296
	297	return err;
7126bd8b AM	298	}
	299
	300	#else
	301
6060fb42	302	static int nand_ecc_test_run(const size_t size)
7126bd8b AM	303	{
	304	return 0;
	305	}
	306
	307	#endif
	308
	309	static int __init ecc_test_init(void)
	310	{
f45c2990	311	int err;
7126bd8b	312
6060fb42	313	err = nand_ecc_test_run(256);
f45c2990 AM	314	if (err)
	315	return err;
	316
6060fb42	317	return nand_ecc_test_run(512);
7126bd8b AM	318	}
	319
	320	static void __exit ecc_test_exit(void)
	321	{
	322	}
	323
	324	module_init(ecc_test_init);
	325	module_exit(ecc_test_exit);
	326
	327	MODULE_DESCRIPTION("NAND ECC function test module");
	328	MODULE_AUTHOR("Akinobu Mita");
	329	MODULE_LICENSE("GPL");