[go: nahoru, domu]
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)					\
22int bch_ ## name ## _h(const char *cp, type *res)		\
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}								\
70
71STRTO_H(strtoint, int)
72STRTO_H(strtouint, unsigned int)
73STRTO_H(strtoll, long long)
74STRTO_H(strtoull, unsigned long long)
75
76ssize_t bch_hprint(char *buf, int64_t v)
77{
78	static const char units[] = "?kMGTPEZY";
79	char dec[4] = "";
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		snprintf(dec, sizeof(dec), ".%i", t / 100);
92
93	return sprintf(buf, "%lli%s%c", v, dec, units[u]);
94}
95
96ssize_t bch_snprint_string_list(char *buf, size_t size, const char * const list[],
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}
109
110ssize_t bch_read_string_list(const char *buf, const char * const list[])
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}
130
131bool bch_is_zero(const char *p, size_t n)
132{
133	size_t i;
134
135	for (i = 0; i < n; i++)
136		if (p[i])
137			return false;
138	return true;
139}
140
141int bch_parse_uuid(const char *s, char *uuid)
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}
168
169void bch_time_stats_update(struct time_stats *stats, uint64_t start_time)
170{
171	uint64_t now, duration, last;
172
173	spin_lock(&stats->lock);
174
175	now		= local_clock();
176	duration	= time_after64(now, start_time)
177		? now - start_time : 0;
178	last		= time_after64(now, stats->last)
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;
195
196	spin_unlock(&stats->lock);
197}
198
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 */
208uint64_t bch_next_delay(struct bch_ratelimit *d, uint64_t done)
209{
210	uint64_t now = local_clock();
211
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;
219
220	return time_after64(d->next, now)
221		? div_u64(d->next - now, NSEC_PER_SEC / HZ)
222		: 0;
223}
224
225void bch_bio_map(struct bio *bio, void *base)
226{
227	size_t size = bio->bi_iter.bi_size;
228	struct bio_vec *bv = bio->bi_io_vec;
229
230	BUG_ON(!bio->bi_iter.bi_size);
231	BUG_ON(bio->bi_vcnt);
232
233	bv->bv_offset = base ? ((unsigned long) base) % PAGE_SIZE : 0;
234	goto start;
235
236	for (; size; bio->bi_vcnt++, bv++) {
237		bv->bv_offset	= 0;
238start:		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}
251
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
273static const uint64_t crc_table[256] = {
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,
360};
361
362uint64_t bch_crc64_update(uint64_t crc, const void *_data, size_t len)
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}
373
374uint64_t bch_crc64(const void *data, size_t len)
375{
376	uint64_t crc = 0xffffffffffffffffULL;
377
378	crc = bch_crc64_update(crc, data, len);
379
380	return crc ^ 0xffffffffffffffffULL;
381}
382