[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[4] = "";
	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)
		snprintf(dec, sizeof(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, duration, last;

	spin_lock(&stats->lock);

	now		= local_clock();
	duration	= time_after64(now, start_time)
		? now - start_time : 0;
	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;

	spin_unlock(&stats->lock);
}

/**
 * bch_next_delay() - increment @d by the amount of work done, and return how
 * long to delay until the next time to do some work.
 *
 * @d - the struct bch_ratelimit to update
 * @done - the amount of work done, in arbitrary units
 *
 * Returns the amount of time to delay by, in jiffies
 */
uint64_t bch_next_delay(struct bch_ratelimit *d, uint64_t done)
{
	uint64_t now = local_clock();

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

	if (time_before64(now + NSEC_PER_SEC, d->next))
		d->next = now + NSEC_PER_SEC;

	if (time_after64(now - NSEC_PER_SEC * 2, d->next))
		d->next = now - NSEC_PER_SEC * 2;

	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_iter.bi_size;
	struct bio_vec *bv = bio->bi_io_vec;

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

	bv->bv_offset = base ? offset_in_page(base) : 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;
	}
}

/*
 * 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] = {
	0x0000000000000000ULL, 0x42F0E1EBA9EA3693ULL, 0x85E1C3D753D46D26ULL,
	0xC711223CFA3E5BB5ULL, 0x493366450E42ECDFULL, 0x0BC387AEA7A8DA4CULL,
	0xCCD2A5925D9681F9ULL, 0x8E224479F47CB76AULL, 0x9266CC8A1C85D9BEULL,
	0xD0962D61B56FEF2DULL, 0x17870F5D4F51B498ULL, 0x5577EEB6E6BB820BULL,
	0xDB55AACF12C73561ULL, 0x99A54B24BB2D03F2ULL, 0x5EB4691841135847ULL,
	0x1C4488F3E8F96ED4ULL, 0x663D78FF90E185EFULL, 0x24CD9914390BB37CULL,
	0xE3DCBB28C335E8C9ULL, 0xA12C5AC36ADFDE5AULL, 0x2F0E1EBA9EA36930ULL,
	0x6DFEFF5137495FA3ULL, 0xAAEFDD6DCD770416ULL, 0xE81F3C86649D3285ULL,
	0xF45BB4758C645C51ULL, 0xB6AB559E258E6AC2ULL, 0x71BA77A2DFB03177ULL,
	0x334A9649765A07E4ULL, 0xBD68D2308226B08EULL, 0xFF9833DB2BCC861DULL,
	0x388911E7D1F2DDA8ULL, 0x7A79F00C7818EB3BULL, 0xCC7AF1FF21C30BDEULL,
	0x8E8A101488293D4DULL, 0x499B3228721766F8ULL, 0x0B6BD3C3DBFD506BULL,
	0x854997BA2F81E701ULL, 0xC7B97651866BD192ULL, 0x00A8546D7C558A27ULL,
	0x4258B586D5BFBCB4ULL, 0x5E1C3D753D46D260ULL, 0x1CECDC9E94ACE4F3ULL,
	0xDBFDFEA26E92BF46ULL, 0x990D1F49C77889D5ULL, 0x172F5B3033043EBFULL,
	0x55DFBADB9AEE082CULL, 0x92CE98E760D05399ULL, 0xD03E790CC93A650AULL,
	0xAA478900B1228E31ULL, 0xE8B768EB18C8B8A2ULL, 0x2FA64AD7E2F6E317ULL,
	0x6D56AB3C4B1CD584ULL, 0xE374EF45BF6062EEULL, 0xA1840EAE168A547DULL,
	0x66952C92ECB40FC8ULL, 0x2465CD79455E395BULL, 0x3821458AADA7578FULL,
	0x7AD1A461044D611CULL, 0xBDC0865DFE733AA9ULL, 0xFF3067B657990C3AULL,
	0x711223CFA3E5BB50ULL, 0x33E2C2240A0F8DC3ULL, 0xF4F3E018F031D676ULL,
	0xB60301F359DBE0E5ULL, 0xDA050215EA6C212FULL, 0x98F5E3FE438617BCULL,
	0x5FE4C1C2B9B84C09ULL, 0x1D14202910527A9AULL, 0x93366450E42ECDF0ULL,
	0xD1C685BB4DC4FB63ULL, 0x16D7A787B7FAA0D6ULL, 0x5427466C1E109645ULL,
	0x4863CE9FF6E9F891ULL, 0x0A932F745F03CE02ULL, 0xCD820D48A53D95B7ULL,
	0x8F72ECA30CD7A324ULL, 0x0150A8DAF8AB144EULL, 0x43A04931514122DDULL,
	0x84B16B0DAB7F7968ULL, 0xC6418AE602954FFBULL, 0xBC387AEA7A8DA4C0ULL,
	0xFEC89B01D3679253ULL, 0x39D9B93D2959C9E6ULL, 0x7B2958D680B3FF75ULL,
	0xF50B1CAF74CF481FULL, 0xB7FBFD44DD257E8CULL, 0x70EADF78271B2539ULL,
	0x321A3E938EF113AAULL, 0x2E5EB66066087D7EULL, 0x6CAE578BCFE24BEDULL,
	0xABBF75B735DC1058ULL, 0xE94F945C9C3626CBULL, 0x676DD025684A91A1ULL,
	0x259D31CEC1A0A732ULL, 0xE28C13F23B9EFC87ULL, 0xA07CF2199274CA14ULL,
	0x167FF3EACBAF2AF1ULL, 0x548F120162451C62ULL, 0x939E303D987B47D7ULL,
	0xD16ED1D631917144ULL, 0x5F4C95AFC5EDC62EULL, 0x1DBC74446C07F0BDULL,
	0xDAAD56789639AB08ULL, 0x985DB7933FD39D9BULL, 0x84193F60D72AF34FULL,
	0xC6E9DE8B7EC0C5DCULL, 0x01F8FCB784FE9E69ULL, 0x43081D5C2D14A8FAULL,
	0xCD2A5925D9681F90ULL, 0x8FDAB8CE70822903ULL, 0x48CB9AF28ABC72B6ULL,
	0x0A3B7B1923564425ULL, 0x70428B155B4EAF1EULL, 0x32B26AFEF2A4998DULL,
	0xF5A348C2089AC238ULL, 0xB753A929A170F4ABULL, 0x3971ED50550C43C1ULL,
	0x7B810CBBFCE67552ULL, 0xBC902E8706D82EE7ULL, 0xFE60CF6CAF321874ULL,
	0xE224479F47CB76A0ULL, 0xA0D4A674EE214033ULL, 0x67C58448141F1B86ULL,
	0x253565A3BDF52D15ULL, 0xAB1721DA49899A7FULL, 0xE9E7C031E063ACECULL,
	0x2EF6E20D1A5DF759ULL, 0x6C0603E6B3B7C1CAULL, 0xF6FAE5C07D3274CDULL,
	0xB40A042BD4D8425EULL, 0x731B26172EE619EBULL, 0x31EBC7FC870C2F78ULL,
	0xBFC9838573709812ULL, 0xFD39626EDA9AAE81ULL, 0x3A28405220A4F534ULL,
	0x78D8A1B9894EC3A7ULL, 0x649C294A61B7AD73ULL, 0x266CC8A1C85D9BE0ULL,
	0xE17DEA9D3263C055ULL, 0xA38D0B769B89F6C6ULL, 0x2DAF4F0F6FF541ACULL,
	0x6F5FAEE4C61F773FULL, 0xA84E8CD83C212C8AULL, 0xEABE6D3395CB1A19ULL,
	0x90C79D3FEDD3F122ULL, 0xD2377CD44439C7B1ULL, 0x15265EE8BE079C04ULL,
	0x57D6BF0317EDAA97ULL, 0xD9F4FB7AE3911DFDULL, 0x9B041A914A7B2B6EULL,
	0x5C1538ADB04570DBULL, 0x1EE5D94619AF4648ULL, 0x02A151B5F156289CULL,
	0x4051B05E58BC1E0FULL, 0x87409262A28245BAULL, 0xC5B073890B687329ULL,
	0x4B9237F0FF14C443ULL, 0x0962D61B56FEF2D0ULL, 0xCE73F427ACC0A965ULL,
	0x8C8315CC052A9FF6ULL, 0x3A80143F5CF17F13ULL, 0x7870F5D4F51B4980ULL,
	0xBF61D7E80F251235ULL, 0xFD913603A6CF24A6ULL, 0x73B3727A52B393CCULL,
	0x31439391FB59A55FULL, 0xF652B1AD0167FEEAULL, 0xB4A25046A88DC879ULL,
	0xA8E6D8B54074A6ADULL, 0xEA16395EE99E903EULL, 0x2D071B6213A0CB8BULL,
	0x6FF7FA89BA4AFD18ULL, 0xE1D5BEF04E364A72ULL, 0xA3255F1BE7DC7CE1ULL,
	0x64347D271DE22754ULL, 0x26C49CCCB40811C7ULL, 0x5CBD6CC0CC10FAFCULL,
	0x1E4D8D2B65FACC6FULL, 0xD95CAF179FC497DAULL, 0x9BAC4EFC362EA149ULL,
	0x158E0A85C2521623ULL, 0x577EEB6E6BB820B0ULL, 0x906FC95291867B05ULL,
	0xD29F28B9386C4D96ULL, 0xCEDBA04AD0952342ULL, 0x8C2B41A1797F15D1ULL,
	0x4B3A639D83414E64ULL, 0x09CA82762AAB78F7ULL, 0x87E8C60FDED7CF9DULL,
	0xC51827E4773DF90EULL, 0x020905D88D03A2BBULL, 0x40F9E43324E99428ULL,
	0x2CFFE7D5975E55E2ULL, 0x6E0F063E3EB46371ULL, 0xA91E2402C48A38C4ULL,
	0xEBEEC5E96D600E57ULL, 0x65CC8190991CB93DULL, 0x273C607B30F68FAEULL,
	0xE02D4247CAC8D41BULL, 0xA2DDA3AC6322E288ULL, 0xBE992B5F8BDB8C5CULL,
	0xFC69CAB42231BACFULL, 0x3B78E888D80FE17AULL, 0x7988096371E5D7E9ULL,
	0xF7AA4D1A85996083ULL, 0xB55AACF12C735610ULL, 0x724B8ECDD64D0DA5ULL,
	0x30BB6F267FA73B36ULL, 0x4AC29F2A07BFD00DULL, 0x08327EC1AE55E69EULL,
	0xCF235CFD546BBD2BULL, 0x8DD3BD16FD818BB8ULL, 0x03F1F96F09FD3CD2ULL,
	0x41011884A0170A41ULL, 0x86103AB85A2951F4ULL, 0xC4E0DB53F3C36767ULL,
	0xD8A453A01B3A09B3ULL, 0x9A54B24BB2D03F20ULL, 0x5D45907748EE6495ULL,
	0x1FB5719CE1045206ULL, 0x919735E51578E56CULL, 0xD367D40EBC92D3FFULL,
	0x1476F63246AC884AULL, 0x568617D9EF46BED9ULL, 0xE085162AB69D5E3CULL,
	0xA275F7C11F7768AFULL, 0x6564D5FDE549331AULL, 0x279434164CA30589ULL,
	0xA9B6706FB8DFB2E3ULL, 0xEB46918411358470ULL, 0x2C57B3B8EB0BDFC5ULL,
	0x6EA7525342E1E956ULL, 0x72E3DAA0AA188782ULL, 0x30133B4B03F2B111ULL,
	0xF7021977F9CCEAA4ULL, 0xB5F2F89C5026DC37ULL, 0x3BD0BCE5A45A6B5DULL,
	0x79205D0E0DB05DCEULL, 0xBE317F32F78E067BULL, 0xFCC19ED95E6430E8ULL,
	0x86B86ED5267CDBD3ULL, 0xC4488F3E8F96ED40ULL, 0x0359AD0275A8B6F5ULL,
	0x41A94CE9DC428066ULL, 0xCF8B0890283E370CULL, 0x8D7BE97B81D4019FULL,
	0x4A6ACB477BEA5A2AULL, 0x089A2AACD2006CB9ULL, 0x14DEA25F3AF9026DULL,
	0x562E43B4931334FEULL, 0x913F6188692D6F4BULL, 0xD3CF8063C0C759D8ULL,
	0x5DEDC41A34BBEEB2ULL, 0x1F1D25F19D51D821ULL, 0xD80C07CD676F8394ULL,
	0x9AFCE626CE85B507ULL,
};

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 = 0xffffffffffffffffULL;

	crc = bch_crc64_update(crc, data, len);

	return crc ^ 0xffffffffffffffffULL;
}
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	{
cafe5635 KO	78	static const char units[] = "?kMGTPEZY";
91bbcfc3	79	char dec[4] = "";
cafe5635 KO	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)
91bbcfc3	91	snprintf(dec, sizeof(dec), ".%i", t / 100);
cafe5635 KO	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	170	{
65d22e91 KO	171	uint64_t now, duration, last;
	172
	173	spin_lock(&stats->lock);
	174
	175	now = local_clock();
	176	duration = time_after64(now, start_time)
cafe5635	177	? now - start_time : 0;
65d22e91	178	last = time_after64(now, stats->last)
cafe5635 KO	179	? now - stats->last : 0;
	180
	181	stats->max_duration = max(stats->max_duration, duration);
	182
	183	if (stats->last) {
	184	ewma_add(stats->average_duration, duration, 8, 8);
	185
	186	if (stats->average_frequency)
	187	ewma_add(stats->average_frequency, last, 8, 8);
	188	else
	189	stats->average_frequency = last << 8;
	190	} else {
	191	stats->average_duration = duration << 8;
	192	}
	193
	194	stats->last = now ?: 1;
65d22e91 KO	195
65d22e91 KO	196	spin_unlock(&stats->lock);
cafe5635	197	}
cafe5635	198
c2a4f318 KO	199	/**
	200	* bch_next_delay() - increment @d by the amount of work done, and return how
	201	* long to delay until the next time to do some work.
	202	*
	203	* @d - the struct bch_ratelimit to update
	204	* @done - the amount of work done, in arbitrary units
	205	*
	206	* Returns the amount of time to delay by, in jiffies
	207	*/
	208	uint64_t bch_next_delay(struct bch_ratelimit *d, uint64_t done)
cafe5635 KO	209	{
	210	uint64_t now = local_clock();
	211
16749c23 KO	212	d->next += div_u64(done * NSEC_PER_SEC, d->rate);
	213
	214	if (time_before64(now + NSEC_PER_SEC, d->next))
	215	d->next = now + NSEC_PER_SEC;
	216
	217	if (time_after64(now - NSEC_PER_SEC * 2, d->next))
	218	d->next = now - NSEC_PER_SEC * 2;
cafe5635 KO	219
	220	return time_after64(d->next, now)
	221	? div_u64(d->next - now, NSEC_PER_SEC / HZ)
	222	: 0;
	223	}
cafe5635	224
169ef1cf	225	void bch_bio_map(struct bio bio, void base)
cafe5635	226	{
4f024f37	227	size_t size = bio->bi_iter.bi_size;
cafe5635 KO	228	struct bio_vec *bv = bio->bi_io_vec;
cafe5635 KO	229
4f024f37	230	BUG_ON(!bio->bi_iter.bi_size);
cafe5635 KO	231	BUG_ON(bio->bi_vcnt);
cafe5635 KO	232
93bbf583	233	bv->bv_offset = base ? offset_in_page(base) : 0;
cafe5635 KO	234	goto start;
	235
	236	for (; size; bio->bi_vcnt++, bv++) {
	237	bv->bv_offset = 0;
	238	start: bv->bv_len = min_t(size_t, PAGE_SIZE - bv->bv_offset,
	239	size);
	240	if (base) {
	241	bv->bv_page = is_vmalloc_addr(base)
	242	? vmalloc_to_page(base)
	243	: virt_to_page(base);
	244
	245	base += bv->bv_len;
	246	}
	247
	248	size -= bv->bv_len;
	249	}
	250	}
cafe5635	251
cafe5635 KO	252	/*
	253	* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group (Any
	254	* use permitted, subject to terms of PostgreSQL license; see.)
	255
	256	* If we have a 64-bit integer type, then a 64-bit CRC looks just like the
	257	* usual sort of implementation. (See Ross Williams' excellent introduction
	258	* A PAINLESS GUIDE TO CRC ERROR DETECTION ALGORITHMS, available from
	259	* ftp://ftp.rocksoft.com/papers/crc_v3.txt or several other net sites.)
	260	* If we have no working 64-bit type, then fake it with two 32-bit registers.
	261	*
	262	* The present implementation is a normal (not "reflected", in Williams'
	263	* terms) 64-bit CRC, using initial all-ones register contents and a final
	264	* bit inversion. The chosen polynomial is borrowed from the DLT1 spec
	265	* (ECMA-182, available from http://www.ecma.ch/ecma1/STAND/ECMA-182.HTM):
	266	*
	267	* x^64 + x^62 + x^57 + x^55 + x^54 + x^53 + x^52 + x^47 + x^46 + x^45 +
	268	* x^40 + x^39 + x^38 + x^37 + x^35 + x^33 + x^32 + x^31 + x^29 + x^27 +
	269	* x^24 + x^23 + x^22 + x^21 + x^19 + x^17 + x^13 + x^12 + x^10 + x^9 +
	270	* x^7 + x^4 + x + 1
	271	*/
	272
	273	static const uint64_t crc_table[256] = {
c19ed23a KO	274	0x0000000000000000ULL, 0x42F0E1EBA9EA3693ULL, 0x85E1C3D753D46D26ULL,
	275	0xC711223CFA3E5BB5ULL, 0x493366450E42ECDFULL, 0x0BC387AEA7A8DA4CULL,
	276	0xCCD2A5925D9681F9ULL, 0x8E224479F47CB76AULL, 0x9266CC8A1C85D9BEULL,
	277	0xD0962D61B56FEF2DULL, 0x17870F5D4F51B498ULL, 0x5577EEB6E6BB820BULL,
	278	0xDB55AACF12C73561ULL, 0x99A54B24BB2D03F2ULL, 0x5EB4691841135847ULL,
	279	0x1C4488F3E8F96ED4ULL, 0x663D78FF90E185EFULL, 0x24CD9914390BB37CULL,
	280	0xE3DCBB28C335E8C9ULL, 0xA12C5AC36ADFDE5AULL, 0x2F0E1EBA9EA36930ULL,
	281	0x6DFEFF5137495FA3ULL, 0xAAEFDD6DCD770416ULL, 0xE81F3C86649D3285ULL,
	282	0xF45BB4758C645C51ULL, 0xB6AB559E258E6AC2ULL, 0x71BA77A2DFB03177ULL,
	283	0x334A9649765A07E4ULL, 0xBD68D2308226B08EULL, 0xFF9833DB2BCC861DULL,
	284	0x388911E7D1F2DDA8ULL, 0x7A79F00C7818EB3BULL, 0xCC7AF1FF21C30BDEULL,
	285	0x8E8A101488293D4DULL, 0x499B3228721766F8ULL, 0x0B6BD3C3DBFD506BULL,
	286	0x854997BA2F81E701ULL, 0xC7B97651866BD192ULL, 0x00A8546D7C558A27ULL,
	287	0x4258B586D5BFBCB4ULL, 0x5E1C3D753D46D260ULL, 0x1CECDC9E94ACE4F3ULL,
	288	0xDBFDFEA26E92BF46ULL, 0x990D1F49C77889D5ULL, 0x172F5B3033043EBFULL,
	289	0x55DFBADB9AEE082CULL, 0x92CE98E760D05399ULL, 0xD03E790CC93A650AULL,
	290	0xAA478900B1228E31ULL, 0xE8B768EB18C8B8A2ULL, 0x2FA64AD7E2F6E317ULL,
	291	0x6D56AB3C4B1CD584ULL, 0xE374EF45BF6062EEULL, 0xA1840EAE168A547DULL,
	292	0x66952C92ECB40FC8ULL, 0x2465CD79455E395BULL, 0x3821458AADA7578FULL,
	293	0x7AD1A461044D611CULL, 0xBDC0865DFE733AA9ULL, 0xFF3067B657990C3AULL,
	294	0x711223CFA3E5BB50ULL, 0x33E2C2240A0F8DC3ULL, 0xF4F3E018F031D676ULL,
	295	0xB60301F359DBE0E5ULL, 0xDA050215EA6C212FULL, 0x98F5E3FE438617BCULL,
	296	0x5FE4C1C2B9B84C09ULL, 0x1D14202910527A9AULL, 0x93366450E42ECDF0ULL,
	297	0xD1C685BB4DC4FB63ULL, 0x16D7A787B7FAA0D6ULL, 0x5427466C1E109645ULL,
	298	0x4863CE9FF6E9F891ULL, 0x0A932F745F03CE02ULL, 0xCD820D48A53D95B7ULL,
	299	0x8F72ECA30CD7A324ULL, 0x0150A8DAF8AB144EULL, 0x43A04931514122DDULL,
	300	0x84B16B0DAB7F7968ULL, 0xC6418AE602954FFBULL, 0xBC387AEA7A8DA4C0ULL,
	301	0xFEC89B01D3679253ULL, 0x39D9B93D2959C9E6ULL, 0x7B2958D680B3FF75ULL,
	302	0xF50B1CAF74CF481FULL, 0xB7FBFD44DD257E8CULL, 0x70EADF78271B2539ULL,
	303	0x321A3E938EF113AAULL, 0x2E5EB66066087D7EULL, 0x6CAE578BCFE24BEDULL,
	304	0xABBF75B735DC1058ULL, 0xE94F945C9C3626CBULL, 0x676DD025684A91A1ULL,
	305	0x259D31CEC1A0A732ULL, 0xE28C13F23B9EFC87ULL, 0xA07CF2199274CA14ULL,
	306	0x167FF3EACBAF2AF1ULL, 0x548F120162451C62ULL, 0x939E303D987B47D7ULL,
	307	0xD16ED1D631917144ULL, 0x5F4C95AFC5EDC62EULL, 0x1DBC74446C07F0BDULL,
	308	0xDAAD56789639AB08ULL, 0x985DB7933FD39D9BULL, 0x84193F60D72AF34FULL,
	309	0xC6E9DE8B7EC0C5DCULL, 0x01F8FCB784FE9E69ULL, 0x43081D5C2D14A8FAULL,
	310	0xCD2A5925D9681F90ULL, 0x8FDAB8CE70822903ULL, 0x48CB9AF28ABC72B6ULL,
	311	0x0A3B7B1923564425ULL, 0x70428B155B4EAF1EULL, 0x32B26AFEF2A4998DULL,
	312	0xF5A348C2089AC238ULL, 0xB753A929A170F4ABULL, 0x3971ED50550C43C1ULL,
	313	0x7B810CBBFCE67552ULL, 0xBC902E8706D82EE7ULL, 0xFE60CF6CAF321874ULL,
	314	0xE224479F47CB76A0ULL, 0xA0D4A674EE214033ULL, 0x67C58448141F1B86ULL,
	315	0x253565A3BDF52D15ULL, 0xAB1721DA49899A7FULL, 0xE9E7C031E063ACECULL,
	316	0x2EF6E20D1A5DF759ULL, 0x6C0603E6B3B7C1CAULL, 0xF6FAE5C07D3274CDULL,
	317	0xB40A042BD4D8425EULL, 0x731B26172EE619EBULL, 0x31EBC7FC870C2F78ULL,
	318	0xBFC9838573709812ULL, 0xFD39626EDA9AAE81ULL, 0x3A28405220A4F534ULL,
	319	0x78D8A1B9894EC3A7ULL, 0x649C294A61B7AD73ULL, 0x266CC8A1C85D9BE0ULL,
	320	0xE17DEA9D3263C055ULL, 0xA38D0B769B89F6C6ULL, 0x2DAF4F0F6FF541ACULL,
	321	0x6F5FAEE4C61F773FULL, 0xA84E8CD83C212C8AULL, 0xEABE6D3395CB1A19ULL,
	322	0x90C79D3FEDD3F122ULL, 0xD2377CD44439C7B1ULL, 0x15265EE8BE079C04ULL,
	323	0x57D6BF0317EDAA97ULL, 0xD9F4FB7AE3911DFDULL, 0x9B041A914A7B2B6EULL,
	324	0x5C1538ADB04570DBULL, 0x1EE5D94619AF4648ULL, 0x02A151B5F156289CULL,
	325	0x4051B05E58BC1E0FULL, 0x87409262A28245BAULL, 0xC5B073890B687329ULL,
	326	0x4B9237F0FF14C443ULL, 0x0962D61B56FEF2D0ULL, 0xCE73F427ACC0A965ULL,
	327	0x8C8315CC052A9FF6ULL, 0x3A80143F5CF17F13ULL, 0x7870F5D4F51B4980ULL,
	328	0xBF61D7E80F251235ULL, 0xFD913603A6CF24A6ULL, 0x73B3727A52B393CCULL,
	329	0x31439391FB59A55FULL, 0xF652B1AD0167FEEAULL, 0xB4A25046A88DC879ULL,
	330	0xA8E6D8B54074A6ADULL, 0xEA16395EE99E903EULL, 0x2D071B6213A0CB8BULL,
	331	0x6FF7FA89BA4AFD18ULL, 0xE1D5BEF04E364A72ULL, 0xA3255F1BE7DC7CE1ULL,
	332	0x64347D271DE22754ULL, 0x26C49CCCB40811C7ULL, 0x5CBD6CC0CC10FAFCULL,
	333	0x1E4D8D2B65FACC6FULL, 0xD95CAF179FC497DAULL, 0x9BAC4EFC362EA149ULL,
	334	0x158E0A85C2521623ULL, 0x577EEB6E6BB820B0ULL, 0x906FC95291867B05ULL,
	335	0xD29F28B9386C4D96ULL, 0xCEDBA04AD0952342ULL, 0x8C2B41A1797F15D1ULL,
	336	0x4B3A639D83414E64ULL, 0x09CA82762AAB78F7ULL, 0x87E8C60FDED7CF9DULL,
	337	0xC51827E4773DF90EULL, 0x020905D88D03A2BBULL, 0x40F9E43324E99428ULL,
338	0x2CFFE7D5975E55E2ULL, 0x6E0F063E3EB46371ULL, 0xA91E2402C48A38C4ULL,
339	0xEBEEC5E96D600E57ULL, 0x65CC8190991CB93DULL, 0x273C607B30F68FAEULL,
340	0xE02D4247CAC8D41BULL, 0xA2DDA3AC6322E288ULL, 0xBE992B5F8BDB8C5CULL,
341	0xFC69CAB42231BACFULL, 0x3B78E888D80FE17AULL, 0x7988096371E5D7E9ULL,
342	0xF7AA4D1A85996083ULL, 0xB55AACF12C735610ULL, 0x724B8ECDD64D0DA5ULL,
343	0x30BB6F267FA73B36ULL, 0x4AC29F2A07BFD00DULL, 0x08327EC1AE55E69EULL,
344	0xCF235CFD546BBD2BULL, 0x8DD3BD16FD818BB8ULL, 0x03F1F96F09FD3CD2ULL,
345	0x41011884A0170A41ULL, 0x86103AB85A2951F4ULL, 0xC4E0DB53F3C36767ULL,
346	0xD8A453A01B3A09B3ULL, 0x9A54B24BB2D03F20ULL, 0x5D45907748EE6495ULL,
347	0x1FB5719CE1045206ULL, 0x919735E51578E56CULL, 0xD367D40EBC92D3FFULL,
348	0x1476F63246AC884AULL, 0x568617D9EF46BED9ULL, 0xE085162AB69D5E3CULL,
349	0xA275F7C11F7768AFULL, 0x6564D5FDE549331AULL, 0x279434164CA30589ULL,
350	0xA9B6706FB8DFB2E3ULL, 0xEB46918411358470ULL, 0x2C57B3B8EB0BDFC5ULL,
351	0x6EA7525342E1E956ULL, 0x72E3DAA0AA188782ULL, 0x30133B4B03F2B111ULL,
352	0xF7021977F9CCEAA4ULL, 0xB5F2F89C5026DC37ULL, 0x3BD0BCE5A45A6B5DULL,
353	0x79205D0E0DB05DCEULL, 0xBE317F32F78E067BULL, 0xFCC19ED95E6430E8ULL,
354	0x86B86ED5267CDBD3ULL, 0xC4488F3E8F96ED40ULL, 0x0359AD0275A8B6F5ULL,
355	0x41A94CE9DC428066ULL, 0xCF8B0890283E370CULL, 0x8D7BE97B81D4019FULL,
356	0x4A6ACB477BEA5A2AULL, 0x089A2AACD2006CB9ULL, 0x14DEA25F3AF9026DULL,
357	0x562E43B4931334FEULL, 0x913F6188692D6F4BULL, 0xD3CF8063C0C759D8ULL,
358	0x5DEDC41A34BBEEB2ULL, 0x1F1D25F19D51D821ULL, 0xD80C07CD676F8394ULL,
359	0x9AFCE626CE85B507ULL,
cafe5635 KO	360	};
cafe5635 KO	361
169ef1cf	362	uint64_t bch_crc64_update(uint64_t crc, const void *_data, size_t len)
cafe5635 KO	363	{
	364	const unsigned char *data = _data;
	365
	366	while (len--) {
	367	int i = ((int) (crc >> 56) ^ *data++) & 0xFF;
	368	crc = crc_table[i] ^ (crc << 8);
	369	}
	370
	371	return crc;
	372	}
cafe5635	373
169ef1cf	374	uint64_t bch_crc64(const void *data, size_t len)
cafe5635	375	{
c19ed23a	376	uint64_t crc = 0xffffffffffffffffULL;
cafe5635	377
169ef1cf	378	crc = bch_crc64_update(crc, data, len);
cafe5635	379
c19ed23a	380	return crc ^ 0xffffffffffffffffULL;
cafe5635	381	}