[linux-2.6-block.git] / drivers / md / bcache / util.c

/*
 * random utiility code, for bcache but in theory not specific to bcache
 *
 * Copyright 2010, 2011 Kent Overstreet <kent.overstreet@gmail.com>
 * Copyright 2012 Google, Inc.
 */

#include <linux/bio.h>
#include <linux/blkdev.h>
#include <linux/ctype.h>
#include <linux/debugfs.h>
#include <linux/module.h>
#include <linux/seq_file.h>
#include <linux/types.h>

#include "util.h"

#define simple_strtoint(c, end, base)	simple_strtol(c, end, base)
#define simple_strtouint(c, end, base)	simple_strtoul(c, end, base)

#define STRTO_H(name, type)					\
int bch_ ## name ## _h(const char *cp, type *res)		\
{								\
	int u = 0;						\
	char *e;						\
	type i = simple_ ## name(cp, &e, 10);			\
								\
	switch (tolower(*e)) {					\
	default:						\
		return -EINVAL;					\
	case 'y':						\
	case 'z':						\
		u++;						\
	case 'e':						\
		u++;						\
	case 'p':						\
		u++;						\
	case 't':						\
		u++;						\
	case 'g':						\
		u++;						\
	case 'm':						\
		u++;						\
	case 'k':						\
		u++;						\
		if (e++ == cp)					\
			return -EINVAL;				\
	case '\n':						\
	case '\0':						\
		if (*e == '\n')					\
			e++;					\
	}							\
								\
	if (*e)							\
		return -EINVAL;					\
								\
	while (u--) {						\
		if ((type) ~0 > 0 &&				\
		    (type) ~0 / 1024 <= i)			\
			return -EINVAL;				\
		if ((i > 0 && ANYSINT_MAX(type) / 1024 < i) ||	\
		    (i < 0 && -ANYSINT_MAX(type) / 1024 > i))	\
			return -EINVAL;				\
		i *= 1024;					\
	}							\
								\
	*res = i;						\
	return 0;						\
}								\

STRTO_H(strtoint, int)
STRTO_H(strtouint, unsigned int)
STRTO_H(strtoll, long long)
STRTO_H(strtoull, unsigned long long)

ssize_t bch_hprint(char *buf, int64_t v)
{
	static const char units[] = "?kMGTPEZY";
	char dec[3] = "";
	int u, t = 0;

	for (u = 0; v >= 1024 || v <= -1024; u++) {
		t = v & ~(~0 << 10);
		v >>= 10;
	}

	if (!u)
		return sprintf(buf, "%llu", v);

	if (v < 100 && v > -100)
		sprintf(dec, ".%i", t / 100);

	return sprintf(buf, "%lli%s%c", v, dec, units[u]);
}

ssize_t bch_snprint_string_list(char *buf, size_t size, const char * const list[],
			    size_t selected)
{
	char *out = buf;
	size_t i;

	for (i = 0; list[i]; i++)
		out += snprintf(out, buf + size - out,
				i == selected ? "[%s] " : "%s ", list[i]);

	out[-1] = '\n';
	return out - buf;
}

ssize_t bch_read_string_list(const char *buf, const char * const list[])
{
	size_t i;
	char *s, *d = kstrndup(buf, PAGE_SIZE - 1, GFP_KERNEL);
	if (!d)
		return -ENOMEM;

	s = strim(d);

	for (i = 0; list[i]; i++)
		if (!strcmp(list[i], s))
			break;

	kfree(d);

	if (!list[i])
		return -EINVAL;

	return i;
}

bool bch_is_zero(const char *p, size_t n)
{
	size_t i;

	for (i = 0; i < n; i++)
		if (p[i])
			return false;
	return true;
}

int bch_parse_uuid(const char *s, char *uuid)
{
	size_t i, j, x;
	memset(uuid, 0, 16);

	for (i = 0, j = 0;
	     i < strspn(s, "-0123456789:ABCDEFabcdef") && j < 32;
	     i++) {
		x = s[i] | 32;

		switch (x) {
		case '0'...'9':
			x -= '0';
			break;
		case 'a'...'f':
			x -= 'a' - 10;
			break;
		default:
			continue;
		}

		if (!(j & 1))
			x <<= 4;
		uuid[j++ >> 1] |= x;
	}
	return i;
}

void bch_time_stats_update(struct time_stats *stats, uint64_t start_time)
{
	uint64_t now		= local_clock();
	uint64_t duration	= time_after64(now, start_time)
		? now - start_time : 0;
	uint64_t last		= time_after64(now, stats->last)
		? now - stats->last : 0;

	stats->max_duration = max(stats->max_duration, duration);

	if (stats->last) {
		ewma_add(stats->average_duration, duration, 8, 8);

		if (stats->average_frequency)
			ewma_add(stats->average_frequency, last, 8, 8);
		else
			stats->average_frequency  = last << 8;
	} else {
		stats->average_duration  = duration << 8;
	}

	stats->last = now ?: 1;
}

unsigned bch_next_delay(struct ratelimit *d, uint64_t done)
{
	uint64_t now = local_clock();

	d->next += div_u64(done, d->rate);

	return time_after64(d->next, now)
		? div_u64(d->next - now, NSEC_PER_SEC / HZ)
		: 0;
}

void bch_bio_map(struct bio *bio, void *base)
{
	size_t size = bio->bi_size;
	struct bio_vec *bv = bio->bi_io_vec;

	BUG_ON(!bio->bi_size);
	BUG_ON(bio->bi_vcnt);

	bv->bv_offset = base ? ((unsigned long) base) % PAGE_SIZE : 0;
	goto start;

	for (; size; bio->bi_vcnt++, bv++) {
		bv->bv_offset	= 0;
start:		bv->bv_len	= min_t(size_t, PAGE_SIZE - bv->bv_offset,
					size);
		if (base) {
			bv->bv_page = is_vmalloc_addr(base)
				? vmalloc_to_page(base)
				: virt_to_page(base);

			base += bv->bv_len;
		}

		size -= bv->bv_len;
	}
}

int bch_bio_alloc_pages(struct bio *bio, gfp_t gfp)
{
	int i;
	struct bio_vec *bv;

	bio_for_each_segment(bv, bio, i) {
		bv->bv_page = alloc_page(gfp);
		if (!bv->bv_page) {
			while (bv-- != bio->bi_io_vec + bio->bi_idx)
				__free_page(bv->bv_page);
			return -ENOMEM;
		}
	}

	return 0;
}

/*
 * Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group (Any
 * use permitted, subject to terms of PostgreSQL license; see.)

 * If we have a 64-bit integer type, then a 64-bit CRC looks just like the
 * usual sort of implementation. (See Ross Williams' excellent introduction
 * A PAINLESS GUIDE TO CRC ERROR DETECTION ALGORITHMS, available from
 * ftp://ftp.rocksoft.com/papers/crc_v3.txt or several other net sites.)
 * If we have no working 64-bit type, then fake it with two 32-bit registers.
 *
 * The present implementation is a normal (not "reflected", in Williams'
 * terms) 64-bit CRC, using initial all-ones register contents and a final
 * bit inversion. The chosen polynomial is borrowed from the DLT1 spec
 * (ECMA-182, available from http://www.ecma.ch/ecma1/STAND/ECMA-182.HTM):
 *
 * x^64 + x^62 + x^57 + x^55 + x^54 + x^53 + x^52 + x^47 + x^46 + x^45 +
 * x^40 + x^39 + x^38 + x^37 + x^35 + x^33 + x^32 + x^31 + x^29 + x^27 +
 * x^24 + x^23 + x^22 + x^21 + x^19 + x^17 + x^13 + x^12 + x^10 + x^9 +
 * x^7 + x^4 + x + 1
*/

static const uint64_t crc_table[256] = {
	0x0000000000000000, 0x42F0E1EBA9EA3693, 0x85E1C3D753D46D26,
	0xC711223CFA3E5BB5, 0x493366450E42ECDF, 0x0BC387AEA7A8DA4C,
	0xCCD2A5925D9681F9, 0x8E224479F47CB76A, 0x9266CC8A1C85D9BE,
	0xD0962D61B56FEF2D, 0x17870F5D4F51B498, 0x5577EEB6E6BB820B,
	0xDB55AACF12C73561, 0x99A54B24BB2D03F2, 0x5EB4691841135847,
	0x1C4488F3E8F96ED4, 0x663D78FF90E185EF, 0x24CD9914390BB37C,
	0xE3DCBB28C335E8C9, 0xA12C5AC36ADFDE5A, 0x2F0E1EBA9EA36930,
	0x6DFEFF5137495FA3, 0xAAEFDD6DCD770416, 0xE81F3C86649D3285,
	0xF45BB4758C645C51, 0xB6AB559E258E6AC2, 0x71BA77A2DFB03177,
	0x334A9649765A07E4, 0xBD68D2308226B08E, 0xFF9833DB2BCC861D,
	0x388911E7D1F2DDA8, 0x7A79F00C7818EB3B, 0xCC7AF1FF21C30BDE,
	0x8E8A101488293D4D, 0x499B3228721766F8, 0x0B6BD3C3DBFD506B,
	0x854997BA2F81E701, 0xC7B97651866BD192, 0x00A8546D7C558A27,
	0x4258B586D5BFBCB4, 0x5E1C3D753D46D260, 0x1CECDC9E94ACE4F3,
	0xDBFDFEA26E92BF46, 0x990D1F49C77889D5, 0x172F5B3033043EBF,
	0x55DFBADB9AEE082C, 0x92CE98E760D05399, 0xD03E790CC93A650A,
	0xAA478900B1228E31, 0xE8B768EB18C8B8A2, 0x2FA64AD7E2F6E317,
	0x6D56AB3C4B1CD584, 0xE374EF45BF6062EE, 0xA1840EAE168A547D,
	0x66952C92ECB40FC8, 0x2465CD79455E395B, 0x3821458AADA7578F,
	0x7AD1A461044D611C, 0xBDC0865DFE733AA9, 0xFF3067B657990C3A,
	0x711223CFA3E5BB50, 0x33E2C2240A0F8DC3, 0xF4F3E018F031D676,
	0xB60301F359DBE0E5, 0xDA050215EA6C212F, 0x98F5E3FE438617BC,
	0x5FE4C1C2B9B84C09, 0x1D14202910527A9A, 0x93366450E42ECDF0,
	0xD1C685BB4DC4FB63, 0x16D7A787B7FAA0D6, 0x5427466C1E109645,
	0x4863CE9FF6E9F891, 0x0A932F745F03CE02, 0xCD820D48A53D95B7,
	0x8F72ECA30CD7A324, 0x0150A8DAF8AB144E, 0x43A04931514122DD,
	0x84B16B0DAB7F7968, 0xC6418AE602954FFB, 0xBC387AEA7A8DA4C0,
	0xFEC89B01D3679253, 0x39D9B93D2959C9E6, 0x7B2958D680B3FF75,
	0xF50B1CAF74CF481F, 0xB7FBFD44DD257E8C, 0x70EADF78271B2539,
	0x321A3E938EF113AA, 0x2E5EB66066087D7E, 0x6CAE578BCFE24BED,
	0xABBF75B735DC1058, 0xE94F945C9C3626CB, 0x676DD025684A91A1,
	0x259D31CEC1A0A732, 0xE28C13F23B9EFC87, 0xA07CF2199274CA14,
	0x167FF3EACBAF2AF1, 0x548F120162451C62, 0x939E303D987B47D7,
	0xD16ED1D631917144, 0x5F4C95AFC5EDC62E, 0x1DBC74446C07F0BD,
	0xDAAD56789639AB08, 0x985DB7933FD39D9B, 0x84193F60D72AF34F,
	0xC6E9DE8B7EC0C5DC, 0x01F8FCB784FE9E69, 0x43081D5C2D14A8FA,
	0xCD2A5925D9681F90, 0x8FDAB8CE70822903, 0x48CB9AF28ABC72B6,
	0x0A3B7B1923564425, 0x70428B155B4EAF1E, 0x32B26AFEF2A4998D,
	0xF5A348C2089AC238, 0xB753A929A170F4AB, 0x3971ED50550C43C1,
	0x7B810CBBFCE67552, 0xBC902E8706D82EE7, 0xFE60CF6CAF321874,
	0xE224479F47CB76A0, 0xA0D4A674EE214033, 0x67C58448141F1B86,
	0x253565A3BDF52D15, 0xAB1721DA49899A7F, 0xE9E7C031E063ACEC,
	0x2EF6E20D1A5DF759, 0x6C0603E6B3B7C1CA, 0xF6FAE5C07D3274CD,
	0xB40A042BD4D8425E, 0x731B26172EE619EB, 0x31EBC7FC870C2F78,
	0xBFC9838573709812, 0xFD39626EDA9AAE81, 0x3A28405220A4F534,
	0x78D8A1B9894EC3A7, 0x649C294A61B7AD73, 0x266CC8A1C85D9BE0,
	0xE17DEA9D3263C055, 0xA38D0B769B89F6C6, 0x2DAF4F0F6FF541AC,
	0x6F5FAEE4C61F773F, 0xA84E8CD83C212C8A, 0xEABE6D3395CB1A19,
	0x90C79D3FEDD3F122, 0xD2377CD44439C7B1, 0x15265EE8BE079C04,
	0x57D6BF0317EDAA97, 0xD9F4FB7AE3911DFD, 0x9B041A914A7B2B6E,
	0x5C1538ADB04570DB, 0x1EE5D94619AF4648, 0x02A151B5F156289C,
	0x4051B05E58BC1E0F, 0x87409262A28245BA, 0xC5B073890B687329,
	0x4B9237F0FF14C443, 0x0962D61B56FEF2D0, 0xCE73F427ACC0A965,
	0x8C8315CC052A9FF6, 0x3A80143F5CF17F13, 0x7870F5D4F51B4980,
	0xBF61D7E80F251235, 0xFD913603A6CF24A6, 0x73B3727A52B393CC,
	0x31439391FB59A55F, 0xF652B1AD0167FEEA, 0xB4A25046A88DC879,
	0xA8E6D8B54074A6AD, 0xEA16395EE99E903E, 0x2D071B6213A0CB8B,
	0x6FF7FA89BA4AFD18, 0xE1D5BEF04E364A72, 0xA3255F1BE7DC7CE1,
	0x64347D271DE22754, 0x26C49CCCB40811C7, 0x5CBD6CC0CC10FAFC,
	0x1E4D8D2B65FACC6F, 0xD95CAF179FC497DA, 0x9BAC4EFC362EA149,
	0x158E0A85C2521623, 0x577EEB6E6BB820B0, 0x906FC95291867B05,
	0xD29F28B9386C4D96, 0xCEDBA04AD0952342, 0x8C2B41A1797F15D1,
	0x4B3A639D83414E64, 0x09CA82762AAB78F7, 0x87E8C60FDED7CF9D,
	0xC51827E4773DF90E, 0x020905D88D03A2BB, 0x40F9E43324E99428,
	0x2CFFE7D5975E55E2, 0x6E0F063E3EB46371, 0xA91E2402C48A38C4,
	0xEBEEC5E96D600E57, 0x65CC8190991CB93D, 0x273C607B30F68FAE,
	0xE02D4247CAC8D41B, 0xA2DDA3AC6322E288, 0xBE992B5F8BDB8C5C,
	0xFC69CAB42231BACF, 0x3B78E888D80FE17A, 0x7988096371E5D7E9,
	0xF7AA4D1A85996083, 0xB55AACF12C735610, 0x724B8ECDD64D0DA5,
	0x30BB6F267FA73B36, 0x4AC29F2A07BFD00D, 0x08327EC1AE55E69E,
	0xCF235CFD546BBD2B, 0x8DD3BD16FD818BB8, 0x03F1F96F09FD3CD2,
	0x41011884A0170A41, 0x86103AB85A2951F4, 0xC4E0DB53F3C36767,
	0xD8A453A01B3A09B3, 0x9A54B24BB2D03F20, 0x5D45907748EE6495,
	0x1FB5719CE1045206, 0x919735E51578E56C, 0xD367D40EBC92D3FF,
	0x1476F63246AC884A, 0x568617D9EF46BED9, 0xE085162AB69D5E3C,
	0xA275F7C11F7768AF, 0x6564D5FDE549331A, 0x279434164CA30589,
	0xA9B6706FB8DFB2E3, 0xEB46918411358470, 0x2C57B3B8EB0BDFC5,
	0x6EA7525342E1E956, 0x72E3DAA0AA188782, 0x30133B4B03F2B111,
	0xF7021977F9CCEAA4, 0xB5F2F89C5026DC37, 0x3BD0BCE5A45A6B5D,
	0x79205D0E0DB05DCE, 0xBE317F32F78E067B, 0xFCC19ED95E6430E8,
	0x86B86ED5267CDBD3, 0xC4488F3E8F96ED40, 0x0359AD0275A8B6F5,
	0x41A94CE9DC428066, 0xCF8B0890283E370C, 0x8D7BE97B81D4019F,
	0x4A6ACB477BEA5A2A, 0x089A2AACD2006CB9, 0x14DEA25F3AF9026D,
	0x562E43B4931334FE, 0x913F6188692D6F4B, 0xD3CF8063C0C759D8,
	0x5DEDC41A34BBEEB2, 0x1F1D25F19D51D821, 0xD80C07CD676F8394,
	0x9AFCE626CE85B507
};

uint64_t bch_crc64_update(uint64_t crc, const void *_data, size_t len)
{
	const unsigned char *data = _data;

	while (len--) {
		int i = ((int) (crc >> 56) ^ *data++) & 0xFF;
		crc = crc_table[i] ^ (crc << 8);
	}

	return crc;
}

uint64_t bch_crc64(const void *data, size_t len)
{
	uint64_t crc = 0xffffffffffffffff;

	crc = bch_crc64_update(crc, data, len);

	return crc ^ 0xffffffffffffffff;
}
Commit	Line	Data
cafe5635 KO	1	/*
	2	* random utiility code, for bcache but in theory not specific to bcache
	3	*
	4	* Copyright 2010, 2011 Kent Overstreet <kent.overstreet@gmail.com>
	5	* Copyright 2012 Google, Inc.
	6	*/
	7
	8	#include <linux/bio.h>
	9	#include <linux/blkdev.h>
	10	#include <linux/ctype.h>
	11	#include <linux/debugfs.h>
	12	#include <linux/module.h>
	13	#include <linux/seq_file.h>
	14	#include <linux/types.h>
	15
	16	#include "util.h"
	17
	18	#define simple_strtoint(c, end, base) simple_strtol(c, end, base)
	19	#define simple_strtouint(c, end, base) simple_strtoul(c, end, base)
	20
	21	#define STRTO_H(name, type) \
169ef1cf	22	int bch_ ## name ## _h(const char cp, type res) \
cafe5635 KO	23	{ \
	24	int u = 0; \
	25	char *e; \
	26	type i = simple_ ## name(cp, &e, 10); \
	27	\
	28	switch (tolower(*e)) { \
	29	default: \
	30	return -EINVAL; \
	31	case 'y': \
	32	case 'z': \
	33	u++; \
	34	case 'e': \
	35	u++; \
	36	case 'p': \
	37	u++; \
	38	case 't': \
	39	u++; \
	40	case 'g': \
	41	u++; \
	42	case 'm': \
	43	u++; \
	44	case 'k': \
	45	u++; \
	46	if (e++ == cp) \
	47	return -EINVAL; \
	48	case '\n': \
	49	case '\0': \
	50	if (*e == '\n') \
	51	e++; \
	52	} \
	53	\
	54	if (*e) \
	55	return -EINVAL; \
	56	\
	57	while (u--) { \
	58	if ((type) ~0 > 0 && \
	59	(type) ~0 / 1024 <= i) \
	60	return -EINVAL; \
	61	if ((i > 0 && ANYSINT_MAX(type) / 1024 < i) \|\| \
	62	(i < 0 && -ANYSINT_MAX(type) / 1024 > i)) \
	63	return -EINVAL; \
	64	i *= 1024; \
	65	} \
	66	\
	67	*res = i; \
	68	return 0; \
	69	} \
cafe5635 KO	70
	71	STRTO_H(strtoint, int)
	72	STRTO_H(strtouint, unsigned int)
	73	STRTO_H(strtoll, long long)
	74	STRTO_H(strtoull, unsigned long long)
	75
169ef1cf	76	ssize_t bch_hprint(char *buf, int64_t v)
cafe5635 KO	77	{
	78	static const char units[] = "?kMGTPEZY";
	79	char dec[3] = "";
	80	int u, t = 0;
	81
	82	for (u = 0; v >= 1024 \|\| v <= -1024; u++) {
	83	t = v & ~(~0 << 10);
	84	v >>= 10;
	85	}
	86
	87	if (!u)
	88	return sprintf(buf, "%llu", v);
	89
	90	if (v < 100 && v > -100)
	91	sprintf(dec, ".%i", t / 100);
	92
	93	return sprintf(buf, "%lli%s%c", v, dec, units[u]);
	94	}
cafe5635	95
169ef1cf	96	ssize_t bch_snprint_string_list(char buf, size_t size, const char const list[],
cafe5635 KO	97	size_t selected)
	98	{
	99	char *out = buf;
	100	size_t i;
	101
	102	for (i = 0; list[i]; i++)
	103	out += snprintf(out, buf + size - out,
	104	i == selected ? "[%s] " : "%s ", list[i]);
	105
	106	out[-1] = '\n';
	107	return out - buf;
	108	}
cafe5635	109
169ef1cf	110	ssize_t bch_read_string_list(const char buf, const char const list[])
cafe5635 KO	111	{
	112	size_t i;
	113	char s, d = kstrndup(buf, PAGE_SIZE - 1, GFP_KERNEL);
	114	if (!d)
	115	return -ENOMEM;
	116
	117	s = strim(d);
	118
	119	for (i = 0; list[i]; i++)
	120	if (!strcmp(list[i], s))
	121	break;
	122
	123	kfree(d);
	124
	125	if (!list[i])
	126	return -EINVAL;
	127
	128	return i;
	129	}
cafe5635	130
169ef1cf	131	bool bch_is_zero(const char *p, size_t n)
cafe5635 KO	132	{
	133	size_t i;
	134
	135	for (i = 0; i < n; i++)
	136	if (p[i])
	137	return false;
	138	return true;
	139	}
cafe5635	140
169ef1cf	141	int bch_parse_uuid(const char s, char uuid)
cafe5635 KO	142	{
	143	size_t i, j, x;
	144	memset(uuid, 0, 16);
	145
	146	for (i = 0, j = 0;
	147	i < strspn(s, "-0123456789:ABCDEFabcdef") && j < 32;
	148	i++) {
	149	x = s[i] \| 32;
	150
	151	switch (x) {
	152	case '0'...'9':
	153	x -= '0';
	154	break;
	155	case 'a'...'f':
	156	x -= 'a' - 10;
	157	break;
	158	default:
	159	continue;
	160	}
	161
	162	if (!(j & 1))
	163	x <<= 4;
	164	uuid[j++ >> 1] \|= x;
	165	}
	166	return i;
	167	}
cafe5635	168
169ef1cf	169	void bch_time_stats_update(struct time_stats *stats, uint64_t start_time)
cafe5635 KO	170	{
	171	uint64_t now = local_clock();
	172	uint64_t duration = time_after64(now, start_time)
	173	? now - start_time : 0;
	174	uint64_t last = time_after64(now, stats->last)
	175	? now - stats->last : 0;
	176
	177	stats->max_duration = max(stats->max_duration, duration);
	178
	179	if (stats->last) {
	180	ewma_add(stats->average_duration, duration, 8, 8);
	181
	182	if (stats->average_frequency)
	183	ewma_add(stats->average_frequency, last, 8, 8);
	184	else
	185	stats->average_frequency = last << 8;
	186	} else {
	187	stats->average_duration = duration << 8;
	188	}
	189
	190	stats->last = now ?: 1;
	191	}
cafe5635	192
169ef1cf	193	unsigned bch_next_delay(struct ratelimit *d, uint64_t done)
cafe5635 KO	194	{
	195	uint64_t now = local_clock();
	196
	197	d->next += div_u64(done, d->rate);
	198
	199	return time_after64(d->next, now)
	200	? div_u64(d->next - now, NSEC_PER_SEC / HZ)
	201	: 0;
	202	}
cafe5635	203
169ef1cf	204	void bch_bio_map(struct bio bio, void base)
cafe5635 KO	205	{
	206	size_t size = bio->bi_size;
	207	struct bio_vec *bv = bio->bi_io_vec;
	208
	209	BUG_ON(!bio->bi_size);
	210	BUG_ON(bio->bi_vcnt);
	211
	212	bv->bv_offset = base ? ((unsigned long) base) % PAGE_SIZE : 0;
	213	goto start;
	214
	215	for (; size; bio->bi_vcnt++, bv++) {
	216	bv->bv_offset = 0;
	217	start: bv->bv_len = min_t(size_t, PAGE_SIZE - bv->bv_offset,
	218	size);
	219	if (base) {
	220	bv->bv_page = is_vmalloc_addr(base)
	221	? vmalloc_to_page(base)
	222	: virt_to_page(base);
	223
	224	base += bv->bv_len;
	225	}
	226
	227	size -= bv->bv_len;
	228	}
	229	}
cafe5635	230
169ef1cf	231	int bch_bio_alloc_pages(struct bio *bio, gfp_t gfp)
cafe5635 KO	232	{
	233	int i;
	234	struct bio_vec *bv;
	235
	236	bio_for_each_segment(bv, bio, i) {
	237	bv->bv_page = alloc_page(gfp);
	238	if (!bv->bv_page) {
	239	while (bv-- != bio->bi_io_vec + bio->bi_idx)
	240	__free_page(bv->bv_page);
	241	return -ENOMEM;
	242	}
	243	}
	244
	245	return 0;
	246	}
cafe5635 KO	247
	248	/*
	249	* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group (Any
	250	* use permitted, subject to terms of PostgreSQL license; see.)
	251
	252	* If we have a 64-bit integer type, then a 64-bit CRC looks just like the
	253	* usual sort of implementation. (See Ross Williams' excellent introduction
	254	* A PAINLESS GUIDE TO CRC ERROR DETECTION ALGORITHMS, available from
	255	* ftp://ftp.rocksoft.com/papers/crc_v3.txt or several other net sites.)
	256	* If we have no working 64-bit type, then fake it with two 32-bit registers.
	257	*
	258	* The present implementation is a normal (not "reflected", in Williams'
	259	* terms) 64-bit CRC, using initial all-ones register contents and a final
	260	* bit inversion. The chosen polynomial is borrowed from the DLT1 spec
	261	* (ECMA-182, available from http://www.ecma.ch/ecma1/STAND/ECMA-182.HTM):
	262	*
	263	* x^64 + x^62 + x^57 + x^55 + x^54 + x^53 + x^52 + x^47 + x^46 + x^45 +
	264	* x^40 + x^39 + x^38 + x^37 + x^35 + x^33 + x^32 + x^31 + x^29 + x^27 +
	265	* x^24 + x^23 + x^22 + x^21 + x^19 + x^17 + x^13 + x^12 + x^10 + x^9 +
	266	* x^7 + x^4 + x + 1
	267	*/
	268
	269	static const uint64_t crc_table[256] = {
	270	0x0000000000000000, 0x42F0E1EBA9EA3693, 0x85E1C3D753D46D26,
	271	0xC711223CFA3E5BB5, 0x493366450E42ECDF, 0x0BC387AEA7A8DA4C,
	272	0xCCD2A5925D9681F9, 0x8E224479F47CB76A, 0x9266CC8A1C85D9BE,
	273	0xD0962D61B56FEF2D, 0x17870F5D4F51B498, 0x5577EEB6E6BB820B,
	274	0xDB55AACF12C73561, 0x99A54B24BB2D03F2, 0x5EB4691841135847,
	275	0x1C4488F3E8F96ED4, 0x663D78FF90E185EF, 0x24CD9914390BB37C,
	276	0xE3DCBB28C335E8C9, 0xA12C5AC36ADFDE5A, 0x2F0E1EBA9EA36930,
	277	0x6DFEFF5137495FA3, 0xAAEFDD6DCD770416, 0xE81F3C86649D3285,
	278	0xF45BB4758C645C51, 0xB6AB559E258E6AC2, 0x71BA77A2DFB03177,
	279	0x334A9649765A07E4, 0xBD68D2308226B08E, 0xFF9833DB2BCC861D,
	280	0x388911E7D1F2DDA8, 0x7A79F00C7818EB3B, 0xCC7AF1FF21C30BDE,
	281	0x8E8A101488293D4D, 0x499B3228721766F8, 0x0B6BD3C3DBFD506B,
	282	0x854997BA2F81E701, 0xC7B97651866BD192, 0x00A8546D7C558A27,
	283	0x4258B586D5BFBCB4, 0x5E1C3D753D46D260, 0x1CECDC9E94ACE4F3,
	284	0xDBFDFEA26E92BF46, 0x990D1F49C77889D5, 0x172F5B3033043EBF,
	285	0x55DFBADB9AEE082C, 0x92CE98E760D05399, 0xD03E790CC93A650A,
	286	0xAA478900B1228E31, 0xE8B768EB18C8B8A2, 0x2FA64AD7E2F6E317,
	287	0x6D56AB3C4B1CD584, 0xE374EF45BF6062EE, 0xA1840EAE168A547D,
	288	0x66952C92ECB40FC8, 0x2465CD79455E395B, 0x3821458AADA7578F,
	289	0x7AD1A461044D611C, 0xBDC0865DFE733AA9, 0xFF3067B657990C3A,
	290	0x711223CFA3E5BB50, 0x33E2C2240A0F8DC3, 0xF4F3E018F031D676,
	291	0xB60301F359DBE0E5, 0xDA050215EA6C212F, 0x98F5E3FE438617BC,
	292	0x5FE4C1C2B9B84C09, 0x1D14202910527A9A, 0x93366450E42ECDF0,
	293	0xD1C685BB4DC4FB63, 0x16D7A787B7FAA0D6, 0x5427466C1E109645,
	294	0x4863CE9FF6E9F891, 0x0A932F745F03CE02, 0xCD820D48A53D95B7,
	295	0x8F72ECA30CD7A324, 0x0150A8DAF8AB144E, 0x43A04931514122DD,
	296	0x84B16B0DAB7F7968, 0xC6418AE602954FFB, 0xBC387AEA7A8DA4C0,
	297	0xFEC89B01D3679253, 0x39D9B93D2959C9E6, 0x7B2958D680B3FF75,
	298	0xF50B1CAF74CF481F, 0xB7FBFD44DD257E8C, 0x70EADF78271B2539,
	299	0x321A3E938EF113AA, 0x2E5EB66066087D7E, 0x6CAE578BCFE24BED,
	300	0xABBF75B735DC1058, 0xE94F945C9C3626CB, 0x676DD025684A91A1,
	301	0x259D31CEC1A0A732, 0xE28C13F23B9EFC87, 0xA07CF2199274CA14,
	302	0x167FF3EACBAF2AF1, 0x548F120162451C62, 0x939E303D987B47D7,
	303	0xD16ED1D631917144, 0x5F4C95AFC5EDC62E, 0x1DBC74446C07F0BD,
	304	0xDAAD56789639AB08, 0x985DB7933FD39D9B, 0x84193F60D72AF34F,
	305	0xC6E9DE8B7EC0C5DC, 0x01F8FCB784FE9E69, 0x43081D5C2D14A8FA,
	306	0xCD2A5925D9681F90, 0x8FDAB8CE70822903, 0x48CB9AF28ABC72B6,
	307	0x0A3B7B1923564425, 0x70428B155B4EAF1E, 0x32B26AFEF2A4998D,
	308	0xF5A348C2089AC238, 0xB753A929A170F4AB, 0x3971ED50550C43C1,
	309	0x7B810CBBFCE67552, 0xBC902E8706D82EE7, 0xFE60CF6CAF321874,
	310	0xE224479F47CB76A0, 0xA0D4A674EE214033, 0x67C58448141F1B86,
311	0x253565A3BDF52D15, 0xAB1721DA49899A7F, 0xE9E7C031E063ACEC,
312	0x2EF6E20D1A5DF759, 0x6C0603E6B3B7C1CA, 0xF6FAE5C07D3274CD,
313	0xB40A042BD4D8425E, 0x731B26172EE619EB, 0x31EBC7FC870C2F78,
314	0xBFC9838573709812, 0xFD39626EDA9AAE81, 0x3A28405220A4F534,
315	0x78D8A1B9894EC3A7, 0x649C294A61B7AD73, 0x266CC8A1C85D9BE0,
316	0xE17DEA9D3263C055, 0xA38D0B769B89F6C6, 0x2DAF4F0F6FF541AC,
317	0x6F5FAEE4C61F773F, 0xA84E8CD83C212C8A, 0xEABE6D3395CB1A19,
318	0x90C79D3FEDD3F122, 0xD2377CD44439C7B1, 0x15265EE8BE079C04,
319	0x57D6BF0317EDAA97, 0xD9F4FB7AE3911DFD, 0x9B041A914A7B2B6E,
320	0x5C1538ADB04570DB, 0x1EE5D94619AF4648, 0x02A151B5F156289C,
321	0x4051B05E58BC1E0F, 0x87409262A28245BA, 0xC5B073890B687329,
322	0x4B9237F0FF14C443, 0x0962D61B56FEF2D0, 0xCE73F427ACC0A965,
323	0x8C8315CC052A9FF6, 0x3A80143F5CF17F13, 0x7870F5D4F51B4980,
324	0xBF61D7E80F251235, 0xFD913603A6CF24A6, 0x73B3727A52B393CC,
325	0x31439391FB59A55F, 0xF652B1AD0167FEEA, 0xB4A25046A88DC879,
326	0xA8E6D8B54074A6AD, 0xEA16395EE99E903E, 0x2D071B6213A0CB8B,
327	0x6FF7FA89BA4AFD18, 0xE1D5BEF04E364A72, 0xA3255F1BE7DC7CE1,
328	0x64347D271DE22754, 0x26C49CCCB40811C7, 0x5CBD6CC0CC10FAFC,
329	0x1E4D8D2B65FACC6F, 0xD95CAF179FC497DA, 0x9BAC4EFC362EA149,
330	0x158E0A85C2521623, 0x577EEB6E6BB820B0, 0x906FC95291867B05,
331	0xD29F28B9386C4D96, 0xCEDBA04AD0952342, 0x8C2B41A1797F15D1,
332	0x4B3A639D83414E64, 0x09CA82762AAB78F7, 0x87E8C60FDED7CF9D,
333	0xC51827E4773DF90E, 0x020905D88D03A2BB, 0x40F9E43324E99428,
334	0x2CFFE7D5975E55E2, 0x6E0F063E3EB46371, 0xA91E2402C48A38C4,
335	0xEBEEC5E96D600E57, 0x65CC8190991CB93D, 0x273C607B30F68FAE,
336	0xE02D4247CAC8D41B, 0xA2DDA3AC6322E288, 0xBE992B5F8BDB8C5C,
337	0xFC69CAB42231BACF, 0x3B78E888D80FE17A, 0x7988096371E5D7E9,
338	0xF7AA4D1A85996083, 0xB55AACF12C735610, 0x724B8ECDD64D0DA5,
339	0x30BB6F267FA73B36, 0x4AC29F2A07BFD00D, 0x08327EC1AE55E69E,
340	0xCF235CFD546BBD2B, 0x8DD3BD16FD818BB8, 0x03F1F96F09FD3CD2,
341	0x41011884A0170A41, 0x86103AB85A2951F4, 0xC4E0DB53F3C36767,
342	0xD8A453A01B3A09B3, 0x9A54B24BB2D03F20, 0x5D45907748EE6495,
343	0x1FB5719CE1045206, 0x919735E51578E56C, 0xD367D40EBC92D3FF,
344	0x1476F63246AC884A, 0x568617D9EF46BED9, 0xE085162AB69D5E3C,
345	0xA275F7C11F7768AF, 0x6564D5FDE549331A, 0x279434164CA30589,
346	0xA9B6706FB8DFB2E3, 0xEB46918411358470, 0x2C57B3B8EB0BDFC5,
347	0x6EA7525342E1E956, 0x72E3DAA0AA188782, 0x30133B4B03F2B111,
348	0xF7021977F9CCEAA4, 0xB5F2F89C5026DC37, 0x3BD0BCE5A45A6B5D,
349	0x79205D0E0DB05DCE, 0xBE317F32F78E067B, 0xFCC19ED95E6430E8,
350	0x86B86ED5267CDBD3, 0xC4488F3E8F96ED40, 0x0359AD0275A8B6F5,
351	0x41A94CE9DC428066, 0xCF8B0890283E370C, 0x8D7BE97B81D4019F,
352	0x4A6ACB477BEA5A2A, 0x089A2AACD2006CB9, 0x14DEA25F3AF9026D,
353	0x562E43B4931334FE, 0x913F6188692D6F4B, 0xD3CF8063C0C759D8,
354	0x5DEDC41A34BBEEB2, 0x1F1D25F19D51D821, 0xD80C07CD676F8394,
355	0x9AFCE626CE85B507
356	};
357
169ef1cf	358	uint64_t bch_crc64_update(uint64_t crc, const void *_data, size_t len)
cafe5635 KO	359	{
	360	const unsigned char *data = _data;
	361
	362	while (len--) {
	363	int i = ((int) (crc >> 56) ^ *data++) & 0xFF;
	364	crc = crc_table[i] ^ (crc << 8);
	365	}
	366
	367	return crc;
	368	}
cafe5635	369
169ef1cf	370	uint64_t bch_crc64(const void *data, size_t len)
cafe5635 KO	371	{
	372	uint64_t crc = 0xffffffffffffffff;
	373
169ef1cf	374	crc = bch_crc64_update(crc, data, len);
cafe5635 KO	375
	376	return crc ^ 0xffffffffffffffff;
	377	}