xref: /linux/drivers/md/bcache/util.c (revision a3a4a816b4b194c45d0217e8b9e08b2639802cda)
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 #include <linux/sched/clock.h>
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)					\
23 int bch_ ## name ## _h(const char *cp, type *res)		\
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 }								\
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 
77 ssize_t bch_hprint(char *buf, int64_t v)
78 {
79 	static const char units[] = "?kMGTPEZY";
80 	char dec[4] = "";
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)
92 		snprintf(dec, sizeof(dec), ".%i", t / 100);
93 
94 	return sprintf(buf, "%lli%s%c", v, dec, units[u]);
95 }
96 
97 ssize_t bch_snprint_string_list(char *buf, size_t size, const char * const list[],
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 }
110 
111 ssize_t bch_read_string_list(const char *buf, const char * const list[])
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 }
131 
132 bool bch_is_zero(const char *p, size_t n)
133 {
134 	size_t i;
135 
136 	for (i = 0; i < n; i++)
137 		if (p[i])
138 			return false;
139 	return true;
140 }
141 
142 int bch_parse_uuid(const char *s, char *uuid)
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 }
169 
170 void bch_time_stats_update(struct time_stats *stats, uint64_t start_time)
171 {
172 	uint64_t now, duration, last;
173 
174 	spin_lock(&stats->lock);
175 
176 	now		= local_clock();
177 	duration	= time_after64(now, start_time)
178 		? now - start_time : 0;
179 	last		= time_after64(now, stats->last)
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;
196 
197 	spin_unlock(&stats->lock);
198 }
199 
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)
210 {
211 	uint64_t now = local_clock();
212 
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;
220 
221 	return time_after64(d->next, now)
222 		? div_u64(d->next - now, NSEC_PER_SEC / HZ)
223 		: 0;
224 }
225 
226 void bch_bio_map(struct bio *bio, void *base)
227 {
228 	size_t size = bio->bi_iter.bi_size;
229 	struct bio_vec *bv = bio->bi_io_vec;
230 
231 	BUG_ON(!bio->bi_iter.bi_size);
232 	BUG_ON(bio->bi_vcnt);
233 
234 	bv->bv_offset = base ? offset_in_page(base) : 0;
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 }
252 
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] = {
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,
361 };
362 
363 uint64_t bch_crc64_update(uint64_t crc, const void *_data, size_t len)
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 }
374 
375 uint64_t bch_crc64(const void *data, size_t len)
376 {
377 	uint64_t crc = 0xffffffffffffffffULL;
378 
379 	crc = bch_crc64_update(crc, data, len);
380 
381 	return crc ^ 0xffffffffffffffffULL;
382 }
383