xref: /linux/drivers/md/bcache/util.c (revision c0c914eca7f251c70facc37dfebeaf176601918d)
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)					\
22 int 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 
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 
76 ssize_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 
96 ssize_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 
110 ssize_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 
131 bool 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 
141 int 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 
169 void 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  */
208 uint64_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 
225 void 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 ? offset_in_page(base) : 0;
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 }
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 
273 static 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 
362 uint64_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 
374 uint64_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