[mirror_ubuntu-bionic-kernel.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 <linux/sched/clock.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>
e6017571	15	#include <linux/sched/clock.h>
cafe5635 KO	16
	17	#include "util.h"
	18
	19	#define simple_strtoint(c, end, base) simple_strtol(c, end, base)
	20	#define simple_strtouint(c, end, base) simple_strtoul(c, end, base)
	21
	22	#define STRTO_H(name, type) \
169ef1cf	23	int bch_ ## name ## _h(const char cp, type res) \
cafe5635 KO	24	{ \
	25	int u = 0; \
	26	char *e; \
	27	type i = simple_ ## name(cp, &e, 10); \
	28	\
	29	switch (tolower(*e)) { \
	30	default: \
	31	return -EINVAL; \
	32	case 'y': \
	33	case 'z': \
	34	u++; \
	35	case 'e': \
	36	u++; \
	37	case 'p': \
	38	u++; \
	39	case 't': \
	40	u++; \
	41	case 'g': \
	42	u++; \
	43	case 'm': \
	44	u++; \
	45	case 'k': \
	46	u++; \
	47	if (e++ == cp) \
	48	return -EINVAL; \
	49	case '\n': \
	50	case '\0': \
	51	if (*e == '\n') \
	52	e++; \
	53	} \
	54	\
	55	if (*e) \
	56	return -EINVAL; \
	57	\
	58	while (u--) { \
	59	if ((type) ~0 > 0 && \
	60	(type) ~0 / 1024 <= i) \
	61	return -EINVAL; \
	62	if ((i > 0 && ANYSINT_MAX(type) / 1024 < i) \|\| \
	63	(i < 0 && -ANYSINT_MAX(type) / 1024 > i)) \
	64	return -EINVAL; \
	65	i *= 1024; \
	66	} \
	67	\
	68	*res = i; \
	69	return 0; \
	70	} \
cafe5635 KO	71
	72	STRTO_H(strtoint, int)
	73	STRTO_H(strtouint, unsigned int)
	74	STRTO_H(strtoll, long long)
	75	STRTO_H(strtoull, unsigned long long)
	76
169ef1cf	77	ssize_t bch_hprint(char *buf, int64_t v)
cafe5635 KO	78	{
cafe5635 KO	79	static const char units[] = "?kMGTPEZY";
91bbcfc3	80	char dec[4] = "";
cafe5635 KO	81	int u, t = 0;
	82
	83	for (u = 0; v >= 1024 \|\| v <= -1024; u++) {
	84	t = v & ~(~0 << 10);
	85	v >>= 10;
	86	}
	87
	88	if (!u)
	89	return sprintf(buf, "%llu", v);
	90
	91	if (v < 100 && v > -100)
91bbcfc3	92	snprintf(dec, sizeof(dec), ".%i", t / 100);
cafe5635 KO	93
	94	return sprintf(buf, "%lli%s%c", v, dec, units[u]);
	95	}
cafe5635	96
169ef1cf	97	ssize_t bch_snprint_string_list(char buf, size_t size, const char const list[],
cafe5635 KO	98	size_t selected)
	99	{
	100	char *out = buf;
	101	size_t i;
	102
	103	for (i = 0; list[i]; i++)
	104	out += snprintf(out, buf + size - out,
	105	i == selected ? "[%s] " : "%s ", list[i]);
	106
	107	out[-1] = '\n';
	108	return out - buf;
	109	}
cafe5635	110
169ef1cf	111	ssize_t bch_read_string_list(const char buf, const char const list[])
cafe5635 KO	112	{
	113	size_t i;
	114	char s, d = kstrndup(buf, PAGE_SIZE - 1, GFP_KERNEL);
	115	if (!d)
	116	return -ENOMEM;
	117
	118	s = strim(d);
	119
	120	for (i = 0; list[i]; i++)
	121	if (!strcmp(list[i], s))
	122	break;
	123
	124	kfree(d);
	125
	126	if (!list[i])
	127	return -EINVAL;
	128
	129	return i;
	130	}
cafe5635	131
169ef1cf	132	bool bch_is_zero(const char *p, size_t n)
cafe5635 KO	133	{
	134	size_t i;
	135
	136	for (i = 0; i < n; i++)
	137	if (p[i])
	138	return false;
	139	return true;
	140	}
cafe5635	141
169ef1cf	142	int bch_parse_uuid(const char s, char uuid)
cafe5635 KO	143	{
	144	size_t i, j, x;
	145	memset(uuid, 0, 16);
	146
	147	for (i = 0, j = 0;
	148	i < strspn(s, "-0123456789:ABCDEFabcdef") && j < 32;
	149	i++) {
	150	x = s[i] \| 32;
	151
	152	switch (x) {
	153	case '0'...'9':
	154	x -= '0';
	155	break;
	156	case 'a'...'f':
	157	x -= 'a' - 10;
	158	break;
	159	default:
	160	continue;
	161	}
	162
	163	if (!(j & 1))
	164	x <<= 4;
	165	uuid[j++ >> 1] \|= x;
	166	}
	167	return i;
	168	}
cafe5635	169
169ef1cf	170	void bch_time_stats_update(struct time_stats *stats, uint64_t start_time)
cafe5635	171	{
65d22e91 KO	172	uint64_t now, duration, last;
	173
	174	spin_lock(&stats->lock);
	175
	176	now = local_clock();
	177	duration = time_after64(now, start_time)
cafe5635	178	? now - start_time : 0;
65d22e91	179	last = time_after64(now, stats->last)
cafe5635 KO	180	? now - stats->last : 0;
	181
	182	stats->max_duration = max(stats->max_duration, duration);
	183
	184	if (stats->last) {
	185	ewma_add(stats->average_duration, duration, 8, 8);
	186
	187	if (stats->average_frequency)
	188	ewma_add(stats->average_frequency, last, 8, 8);
	189	else
	190	stats->average_frequency = last << 8;
	191	} else {
	192	stats->average_duration = duration << 8;
	193	}
	194
	195	stats->last = now ?: 1;
65d22e91 KO	196
65d22e91 KO	197	spin_unlock(&stats->lock);
cafe5635	198	}
cafe5635	199
c2a4f318 KO	200	/**
	201	* bch_next_delay() - increment @d by the amount of work done, and return how
	202	* long to delay until the next time to do some work.
	203	*
	204	* @d - the struct bch_ratelimit to update
	205	* @done - the amount of work done, in arbitrary units
	206	*
	207	* Returns the amount of time to delay by, in jiffies
	208	*/
	209	uint64_t bch_next_delay(struct bch_ratelimit *d, uint64_t done)
cafe5635 KO	210	{
	211	uint64_t now = local_clock();
	212
16749c23 KO	213	d->next += div_u64(done * NSEC_PER_SEC, d->rate);
	214
	215	if (time_before64(now + NSEC_PER_SEC, d->next))
	216	d->next = now + NSEC_PER_SEC;
	217
	218	if (time_after64(now - NSEC_PER_SEC * 2, d->next))
	219	d->next = now - NSEC_PER_SEC * 2;
cafe5635 KO	220
	221	return time_after64(d->next, now)
	222	? div_u64(d->next - now, NSEC_PER_SEC / HZ)
	223	: 0;
	224	}
cafe5635	225
169ef1cf	226	void bch_bio_map(struct bio bio, void base)
cafe5635	227	{
4f024f37	228	size_t size = bio->bi_iter.bi_size;
cafe5635 KO	229	struct bio_vec *bv = bio->bi_io_vec;
cafe5635 KO	230
4f024f37	231	BUG_ON(!bio->bi_iter.bi_size);
cafe5635 KO	232	BUG_ON(bio->bi_vcnt);
cafe5635 KO	233
93bbf583	234	bv->bv_offset = base ? offset_in_page(base) : 0;
cafe5635 KO	235	goto start;
	236
	237	for (; size; bio->bi_vcnt++, bv++) {
	238	bv->bv_offset = 0;
	239	start: bv->bv_len = min_t(size_t, PAGE_SIZE - bv->bv_offset,
	240	size);
	241	if (base) {
	242	bv->bv_page = is_vmalloc_addr(base)
	243	? vmalloc_to_page(base)
	244	: virt_to_page(base);
	245
	246	base += bv->bv_len;
	247	}
	248
	249	size -= bv->bv_len;
	250	}
	251	}
cafe5635	252
cafe5635 KO	253	/*
	254	* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group (Any
	255	* use permitted, subject to terms of PostgreSQL license; see.)
	256
	257	* If we have a 64-bit integer type, then a 64-bit CRC looks just like the
	258	* usual sort of implementation. (See Ross Williams' excellent introduction
	259	* A PAINLESS GUIDE TO CRC ERROR DETECTION ALGORITHMS, available from
	260	* ftp://ftp.rocksoft.com/papers/crc_v3.txt or several other net sites.)
	261	* If we have no working 64-bit type, then fake it with two 32-bit registers.
	262	*
	263	* The present implementation is a normal (not "reflected", in Williams'
	264	* terms) 64-bit CRC, using initial all-ones register contents and a final
	265	* bit inversion. The chosen polynomial is borrowed from the DLT1 spec
	266	* (ECMA-182, available from http://www.ecma.ch/ecma1/STAND/ECMA-182.HTM):
	267	*
	268	* x^64 + x^62 + x^57 + x^55 + x^54 + x^53 + x^52 + x^47 + x^46 + x^45 +
	269	* x^40 + x^39 + x^38 + x^37 + x^35 + x^33 + x^32 + x^31 + x^29 + x^27 +
	270	* x^24 + x^23 + x^22 + x^21 + x^19 + x^17 + x^13 + x^12 + x^10 + x^9 +
	271	* x^7 + x^4 + x + 1
	272	*/
	273
	274	static const uint64_t crc_table[256] = {
c19ed23a KO	275	0x0000000000000000ULL, 0x42F0E1EBA9EA3693ULL, 0x85E1C3D753D46D26ULL,
	276	0xC711223CFA3E5BB5ULL, 0x493366450E42ECDFULL, 0x0BC387AEA7A8DA4CULL,
	277	0xCCD2A5925D9681F9ULL, 0x8E224479F47CB76AULL, 0x9266CC8A1C85D9BEULL,
	278	0xD0962D61B56FEF2DULL, 0x17870F5D4F51B498ULL, 0x5577EEB6E6BB820BULL,
	279	0xDB55AACF12C73561ULL, 0x99A54B24BB2D03F2ULL, 0x5EB4691841135847ULL,
	280	0x1C4488F3E8F96ED4ULL, 0x663D78FF90E185EFULL, 0x24CD9914390BB37CULL,
	281	0xE3DCBB28C335E8C9ULL, 0xA12C5AC36ADFDE5AULL, 0x2F0E1EBA9EA36930ULL,
	282	0x6DFEFF5137495FA3ULL, 0xAAEFDD6DCD770416ULL, 0xE81F3C86649D3285ULL,
	283	0xF45BB4758C645C51ULL, 0xB6AB559E258E6AC2ULL, 0x71BA77A2DFB03177ULL,
	284	0x334A9649765A07E4ULL, 0xBD68D2308226B08EULL, 0xFF9833DB2BCC861DULL,
	285	0x388911E7D1F2DDA8ULL, 0x7A79F00C7818EB3BULL, 0xCC7AF1FF21C30BDEULL,
	286	0x8E8A101488293D4DULL, 0x499B3228721766F8ULL, 0x0B6BD3C3DBFD506BULL,
	287	0x854997BA2F81E701ULL, 0xC7B97651866BD192ULL, 0x00A8546D7C558A27ULL,
	288	0x4258B586D5BFBCB4ULL, 0x5E1C3D753D46D260ULL, 0x1CECDC9E94ACE4F3ULL,
	289	0xDBFDFEA26E92BF46ULL, 0x990D1F49C77889D5ULL, 0x172F5B3033043EBFULL,
	290	0x55DFBADB9AEE082CULL, 0x92CE98E760D05399ULL, 0xD03E790CC93A650AULL,
	291	0xAA478900B1228E31ULL, 0xE8B768EB18C8B8A2ULL, 0x2FA64AD7E2F6E317ULL,
	292	0x6D56AB3C4B1CD584ULL, 0xE374EF45BF6062EEULL, 0xA1840EAE168A547DULL,
	293	0x66952C92ECB40FC8ULL, 0x2465CD79455E395BULL, 0x3821458AADA7578FULL,
	294	0x7AD1A461044D611CULL, 0xBDC0865DFE733AA9ULL, 0xFF3067B657990C3AULL,
	295	0x711223CFA3E5BB50ULL, 0x33E2C2240A0F8DC3ULL, 0xF4F3E018F031D676ULL,
	296	0xB60301F359DBE0E5ULL, 0xDA050215EA6C212FULL, 0x98F5E3FE438617BCULL,
	297	0x5FE4C1C2B9B84C09ULL, 0x1D14202910527A9AULL, 0x93366450E42ECDF0ULL,
	298	0xD1C685BB4DC4FB63ULL, 0x16D7A787B7FAA0D6ULL, 0x5427466C1E109645ULL,
	299	0x4863CE9FF6E9F891ULL, 0x0A932F745F03CE02ULL, 0xCD820D48A53D95B7ULL,
	300	0x8F72ECA30CD7A324ULL, 0x0150A8DAF8AB144EULL, 0x43A04931514122DDULL,
	301	0x84B16B0DAB7F7968ULL, 0xC6418AE602954FFBULL, 0xBC387AEA7A8DA4C0ULL,
	302	0xFEC89B01D3679253ULL, 0x39D9B93D2959C9E6ULL, 0x7B2958D680B3FF75ULL,
	303	0xF50B1CAF74CF481FULL, 0xB7FBFD44DD257E8CULL, 0x70EADF78271B2539ULL,
	304	0x321A3E938EF113AAULL, 0x2E5EB66066087D7EULL, 0x6CAE578BCFE24BEDULL,
	305	0xABBF75B735DC1058ULL, 0xE94F945C9C3626CBULL, 0x676DD025684A91A1ULL,
	306	0x259D31CEC1A0A732ULL, 0xE28C13F23B9EFC87ULL, 0xA07CF2199274CA14ULL,
	307	0x167FF3EACBAF2AF1ULL, 0x548F120162451C62ULL, 0x939E303D987B47D7ULL,
	308	0xD16ED1D631917144ULL, 0x5F4C95AFC5EDC62EULL, 0x1DBC74446C07F0BDULL,
	309	0xDAAD56789639AB08ULL, 0x985DB7933FD39D9BULL, 0x84193F60D72AF34FULL,
	310	0xC6E9DE8B7EC0C5DCULL, 0x01F8FCB784FE9E69ULL, 0x43081D5C2D14A8FAULL,
	311	0xCD2A5925D9681F90ULL, 0x8FDAB8CE70822903ULL, 0x48CB9AF28ABC72B6ULL,
	312	0x0A3B7B1923564425ULL, 0x70428B155B4EAF1EULL, 0x32B26AFEF2A4998DULL,
	313	0xF5A348C2089AC238ULL, 0xB753A929A170F4ABULL, 0x3971ED50550C43C1ULL,
	314	0x7B810CBBFCE67552ULL, 0xBC902E8706D82EE7ULL, 0xFE60CF6CAF321874ULL,
	315	0xE224479F47CB76A0ULL, 0xA0D4A674EE214033ULL, 0x67C58448141F1B86ULL,
	316	0x253565A3BDF52D15ULL, 0xAB1721DA49899A7FULL, 0xE9E7C031E063ACECULL,
	317	0x2EF6E20D1A5DF759ULL, 0x6C0603E6B3B7C1CAULL, 0xF6FAE5C07D3274CDULL,
	318	0xB40A042BD4D8425EULL, 0x731B26172EE619EBULL, 0x31EBC7FC870C2F78ULL,
	319	0xBFC9838573709812ULL, 0xFD39626EDA9AAE81ULL, 0x3A28405220A4F534ULL,
	320	0x78D8A1B9894EC3A7ULL, 0x649C294A61B7AD73ULL, 0x266CC8A1C85D9BE0ULL,
	321	0xE17DEA9D3263C055ULL, 0xA38D0B769B89F6C6ULL, 0x2DAF4F0F6FF541ACULL,
	322	0x6F5FAEE4C61F773FULL, 0xA84E8CD83C212C8AULL, 0xEABE6D3395CB1A19ULL,
	323	0x90C79D3FEDD3F122ULL, 0xD2377CD44439C7B1ULL, 0x15265EE8BE079C04ULL,
	324	0x57D6BF0317EDAA97ULL, 0xD9F4FB7AE3911DFDULL, 0x9B041A914A7B2B6EULL,
	325	0x5C1538ADB04570DBULL, 0x1EE5D94619AF4648ULL, 0x02A151B5F156289CULL,
	326	0x4051B05E58BC1E0FULL, 0x87409262A28245BAULL, 0xC5B073890B687329ULL,
	327	0x4B9237F0FF14C443ULL, 0x0962D61B56FEF2D0ULL, 0xCE73F427ACC0A965ULL,
	328	0x8C8315CC052A9FF6ULL, 0x3A80143F5CF17F13ULL, 0x7870F5D4F51B4980ULL,
	329	0xBF61D7E80F251235ULL, 0xFD913603A6CF24A6ULL, 0x73B3727A52B393CCULL,
	330	0x31439391FB59A55FULL, 0xF652B1AD0167FEEAULL, 0xB4A25046A88DC879ULL,
	331	0xA8E6D8B54074A6ADULL, 0xEA16395EE99E903EULL, 0x2D071B6213A0CB8BULL,
	332	0x6FF7FA89BA4AFD18ULL, 0xE1D5BEF04E364A72ULL, 0xA3255F1BE7DC7CE1ULL,
	333	0x64347D271DE22754ULL, 0x26C49CCCB40811C7ULL, 0x5CBD6CC0CC10FAFCULL,
	334	0x1E4D8D2B65FACC6FULL, 0xD95CAF179FC497DAULL, 0x9BAC4EFC362EA149ULL,
	335	0x158E0A85C2521623ULL, 0x577EEB6E6BB820B0ULL, 0x906FC95291867B05ULL,
	336	0xD29F28B9386C4D96ULL, 0xCEDBA04AD0952342ULL, 0x8C2B41A1797F15D1ULL,
	337	0x4B3A639D83414E64ULL, 0x09CA82762AAB78F7ULL, 0x87E8C60FDED7CF9DULL,
	338	0xC51827E4773DF90EULL, 0x020905D88D03A2BBULL, 0x40F9E43324E99428ULL,
339	0x2CFFE7D5975E55E2ULL, 0x6E0F063E3EB46371ULL, 0xA91E2402C48A38C4ULL,
340	0xEBEEC5E96D600E57ULL, 0x65CC8190991CB93DULL, 0x273C607B30F68FAEULL,
341	0xE02D4247CAC8D41BULL, 0xA2DDA3AC6322E288ULL, 0xBE992B5F8BDB8C5CULL,
342	0xFC69CAB42231BACFULL, 0x3B78E888D80FE17AULL, 0x7988096371E5D7E9ULL,
343	0xF7AA4D1A85996083ULL, 0xB55AACF12C735610ULL, 0x724B8ECDD64D0DA5ULL,
344	0x30BB6F267FA73B36ULL, 0x4AC29F2A07BFD00DULL, 0x08327EC1AE55E69EULL,
345	0xCF235CFD546BBD2BULL, 0x8DD3BD16FD818BB8ULL, 0x03F1F96F09FD3CD2ULL,
346	0x41011884A0170A41ULL, 0x86103AB85A2951F4ULL, 0xC4E0DB53F3C36767ULL,
347	0xD8A453A01B3A09B3ULL, 0x9A54B24BB2D03F20ULL, 0x5D45907748EE6495ULL,
348	0x1FB5719CE1045206ULL, 0x919735E51578E56CULL, 0xD367D40EBC92D3FFULL,
349	0x1476F63246AC884AULL, 0x568617D9EF46BED9ULL, 0xE085162AB69D5E3CULL,
350	0xA275F7C11F7768AFULL, 0x6564D5FDE549331AULL, 0x279434164CA30589ULL,
351	0xA9B6706FB8DFB2E3ULL, 0xEB46918411358470ULL, 0x2C57B3B8EB0BDFC5ULL,
352	0x6EA7525342E1E956ULL, 0x72E3DAA0AA188782ULL, 0x30133B4B03F2B111ULL,
353	0xF7021977F9CCEAA4ULL, 0xB5F2F89C5026DC37ULL, 0x3BD0BCE5A45A6B5DULL,
354	0x79205D0E0DB05DCEULL, 0xBE317F32F78E067BULL, 0xFCC19ED95E6430E8ULL,
355	0x86B86ED5267CDBD3ULL, 0xC4488F3E8F96ED40ULL, 0x0359AD0275A8B6F5ULL,
356	0x41A94CE9DC428066ULL, 0xCF8B0890283E370CULL, 0x8D7BE97B81D4019FULL,
357	0x4A6ACB477BEA5A2AULL, 0x089A2AACD2006CB9ULL, 0x14DEA25F3AF9026DULL,
358	0x562E43B4931334FEULL, 0x913F6188692D6F4BULL, 0xD3CF8063C0C759D8ULL,
359	0x5DEDC41A34BBEEB2ULL, 0x1F1D25F19D51D821ULL, 0xD80C07CD676F8394ULL,
360	0x9AFCE626CE85B507ULL,
cafe5635 KO	361	};
cafe5635 KO	362
169ef1cf	363	uint64_t bch_crc64_update(uint64_t crc, const void *_data, size_t len)
cafe5635 KO	364	{
	365	const unsigned char *data = _data;
	366
	367	while (len--) {
	368	int i = ((int) (crc >> 56) ^ *data++) & 0xFF;
	369	crc = crc_table[i] ^ (crc << 8);
	370	}
	371
	372	return crc;
	373	}
cafe5635	374
169ef1cf	375	uint64_t bch_crc64(const void *data, size_t len)
cafe5635	376	{
c19ed23a	377	uint64_t crc = 0xffffffffffffffffULL;
cafe5635	378
169ef1cf	379	crc = bch_crc64_update(crc, data, len);
cafe5635	380
c19ed23a	381	return crc ^ 0xffffffffffffffffULL;
cafe5635	382	}