xref: /openbmc/linux/drivers/md/bcache/util.c (revision 711aab1d)
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 /**
78  * bch_hprint() - formats @v to human readable string for sysfs.
79  *
80  * @v - signed 64 bit integer
81  * @buf - the (at least 8 byte) buffer to format the result into.
82  *
83  * Returns the number of bytes used by format.
84  */
85 ssize_t bch_hprint(char *buf, int64_t v)
86 {
87 	static const char units[] = "?kMGTPEZY";
88 	int u = 0, t;
89 
90 	uint64_t q;
91 
92 	if (v < 0)
93 		q = -v;
94 	else
95 		q = v;
96 
97 	/* For as long as the number is more than 3 digits, but at least
98 	 * once, shift right / divide by 1024.  Keep the remainder for
99 	 * a digit after the decimal point.
100 	 */
101 	do {
102 		u++;
103 
104 		t = q & ~(~0 << 10);
105 		q >>= 10;
106 	} while (q >= 1000);
107 
108 	if (v < 0)
109 		/* '-', up to 3 digits, '.', 1 digit, 1 character, null;
110 		 * yields 8 bytes.
111 		 */
112 		return sprintf(buf, "-%llu.%i%c", q, t * 10 / 1024, units[u]);
113 	else
114 		return sprintf(buf, "%llu.%i%c", q, t * 10 / 1024, units[u]);
115 }
116 
117 ssize_t bch_snprint_string_list(char *buf, size_t size, const char * const list[],
118 			    size_t selected)
119 {
120 	char *out = buf;
121 	size_t i;
122 
123 	for (i = 0; list[i]; i++)
124 		out += snprintf(out, buf + size - out,
125 				i == selected ? "[%s] " : "%s ", list[i]);
126 
127 	out[-1] = '\n';
128 	return out - buf;
129 }
130 
131 ssize_t bch_read_string_list(const char *buf, const char * const list[])
132 {
133 	size_t i;
134 	char *s, *d = kstrndup(buf, PAGE_SIZE - 1, GFP_KERNEL);
135 	if (!d)
136 		return -ENOMEM;
137 
138 	s = strim(d);
139 
140 	for (i = 0; list[i]; i++)
141 		if (!strcmp(list[i], s))
142 			break;
143 
144 	kfree(d);
145 
146 	if (!list[i])
147 		return -EINVAL;
148 
149 	return i;
150 }
151 
152 bool bch_is_zero(const char *p, size_t n)
153 {
154 	size_t i;
155 
156 	for (i = 0; i < n; i++)
157 		if (p[i])
158 			return false;
159 	return true;
160 }
161 
162 int bch_parse_uuid(const char *s, char *uuid)
163 {
164 	size_t i, j, x;
165 	memset(uuid, 0, 16);
166 
167 	for (i = 0, j = 0;
168 	     i < strspn(s, "-0123456789:ABCDEFabcdef") && j < 32;
169 	     i++) {
170 		x = s[i] | 32;
171 
172 		switch (x) {
173 		case '0'...'9':
174 			x -= '0';
175 			break;
176 		case 'a'...'f':
177 			x -= 'a' - 10;
178 			break;
179 		default:
180 			continue;
181 		}
182 
183 		if (!(j & 1))
184 			x <<= 4;
185 		uuid[j++ >> 1] |= x;
186 	}
187 	return i;
188 }
189 
190 void bch_time_stats_update(struct time_stats *stats, uint64_t start_time)
191 {
192 	uint64_t now, duration, last;
193 
194 	spin_lock(&stats->lock);
195 
196 	now		= local_clock();
197 	duration	= time_after64(now, start_time)
198 		? now - start_time : 0;
199 	last		= time_after64(now, stats->last)
200 		? now - stats->last : 0;
201 
202 	stats->max_duration = max(stats->max_duration, duration);
203 
204 	if (stats->last) {
205 		ewma_add(stats->average_duration, duration, 8, 8);
206 
207 		if (stats->average_frequency)
208 			ewma_add(stats->average_frequency, last, 8, 8);
209 		else
210 			stats->average_frequency  = last << 8;
211 	} else {
212 		stats->average_duration  = duration << 8;
213 	}
214 
215 	stats->last = now ?: 1;
216 
217 	spin_unlock(&stats->lock);
218 }
219 
220 /**
221  * bch_next_delay() - increment @d by the amount of work done, and return how
222  * long to delay until the next time to do some work.
223  *
224  * @d - the struct bch_ratelimit to update
225  * @done - the amount of work done, in arbitrary units
226  *
227  * Returns the amount of time to delay by, in jiffies
228  */
229 uint64_t bch_next_delay(struct bch_ratelimit *d, uint64_t done)
230 {
231 	uint64_t now = local_clock();
232 
233 	d->next += div_u64(done * NSEC_PER_SEC, d->rate);
234 
235 	if (time_before64(now + NSEC_PER_SEC, d->next))
236 		d->next = now + NSEC_PER_SEC;
237 
238 	if (time_after64(now - NSEC_PER_SEC * 2, d->next))
239 		d->next = now - NSEC_PER_SEC * 2;
240 
241 	return time_after64(d->next, now)
242 		? div_u64(d->next - now, NSEC_PER_SEC / HZ)
243 		: 0;
244 }
245 
246 void bch_bio_map(struct bio *bio, void *base)
247 {
248 	size_t size = bio->bi_iter.bi_size;
249 	struct bio_vec *bv = bio->bi_io_vec;
250 
251 	BUG_ON(!bio->bi_iter.bi_size);
252 	BUG_ON(bio->bi_vcnt);
253 
254 	bv->bv_offset = base ? offset_in_page(base) : 0;
255 	goto start;
256 
257 	for (; size; bio->bi_vcnt++, bv++) {
258 		bv->bv_offset	= 0;
259 start:		bv->bv_len	= min_t(size_t, PAGE_SIZE - bv->bv_offset,
260 					size);
261 		if (base) {
262 			bv->bv_page = is_vmalloc_addr(base)
263 				? vmalloc_to_page(base)
264 				: virt_to_page(base);
265 
266 			base += bv->bv_len;
267 		}
268 
269 		size -= bv->bv_len;
270 	}
271 }
272 
273 /*
274  * Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group (Any
275  * use permitted, subject to terms of PostgreSQL license; see.)
276 
277  * If we have a 64-bit integer type, then a 64-bit CRC looks just like the
278  * usual sort of implementation. (See Ross Williams' excellent introduction
279  * A PAINLESS GUIDE TO CRC ERROR DETECTION ALGORITHMS, available from
280  * ftp://ftp.rocksoft.com/papers/crc_v3.txt or several other net sites.)
281  * If we have no working 64-bit type, then fake it with two 32-bit registers.
282  *
283  * The present implementation is a normal (not "reflected", in Williams'
284  * terms) 64-bit CRC, using initial all-ones register contents and a final
285  * bit inversion. The chosen polynomial is borrowed from the DLT1 spec
286  * (ECMA-182, available from http://www.ecma.ch/ecma1/STAND/ECMA-182.HTM):
287  *
288  * x^64 + x^62 + x^57 + x^55 + x^54 + x^53 + x^52 + x^47 + x^46 + x^45 +
289  * x^40 + x^39 + x^38 + x^37 + x^35 + x^33 + x^32 + x^31 + x^29 + x^27 +
290  * x^24 + x^23 + x^22 + x^21 + x^19 + x^17 + x^13 + x^12 + x^10 + x^9 +
291  * x^7 + x^4 + x + 1
292 */
293 
294 static const uint64_t crc_table[256] = {
295 	0x0000000000000000ULL, 0x42F0E1EBA9EA3693ULL, 0x85E1C3D753D46D26ULL,
296 	0xC711223CFA3E5BB5ULL, 0x493366450E42ECDFULL, 0x0BC387AEA7A8DA4CULL,
297 	0xCCD2A5925D9681F9ULL, 0x8E224479F47CB76AULL, 0x9266CC8A1C85D9BEULL,
298 	0xD0962D61B56FEF2DULL, 0x17870F5D4F51B498ULL, 0x5577EEB6E6BB820BULL,
299 	0xDB55AACF12C73561ULL, 0x99A54B24BB2D03F2ULL, 0x5EB4691841135847ULL,
300 	0x1C4488F3E8F96ED4ULL, 0x663D78FF90E185EFULL, 0x24CD9914390BB37CULL,
301 	0xE3DCBB28C335E8C9ULL, 0xA12C5AC36ADFDE5AULL, 0x2F0E1EBA9EA36930ULL,
302 	0x6DFEFF5137495FA3ULL, 0xAAEFDD6DCD770416ULL, 0xE81F3C86649D3285ULL,
303 	0xF45BB4758C645C51ULL, 0xB6AB559E258E6AC2ULL, 0x71BA77A2DFB03177ULL,
304 	0x334A9649765A07E4ULL, 0xBD68D2308226B08EULL, 0xFF9833DB2BCC861DULL,
305 	0x388911E7D1F2DDA8ULL, 0x7A79F00C7818EB3BULL, 0xCC7AF1FF21C30BDEULL,
306 	0x8E8A101488293D4DULL, 0x499B3228721766F8ULL, 0x0B6BD3C3DBFD506BULL,
307 	0x854997BA2F81E701ULL, 0xC7B97651866BD192ULL, 0x00A8546D7C558A27ULL,
308 	0x4258B586D5BFBCB4ULL, 0x5E1C3D753D46D260ULL, 0x1CECDC9E94ACE4F3ULL,
309 	0xDBFDFEA26E92BF46ULL, 0x990D1F49C77889D5ULL, 0x172F5B3033043EBFULL,
310 	0x55DFBADB9AEE082CULL, 0x92CE98E760D05399ULL, 0xD03E790CC93A650AULL,
311 	0xAA478900B1228E31ULL, 0xE8B768EB18C8B8A2ULL, 0x2FA64AD7E2F6E317ULL,
312 	0x6D56AB3C4B1CD584ULL, 0xE374EF45BF6062EEULL, 0xA1840EAE168A547DULL,
313 	0x66952C92ECB40FC8ULL, 0x2465CD79455E395BULL, 0x3821458AADA7578FULL,
314 	0x7AD1A461044D611CULL, 0xBDC0865DFE733AA9ULL, 0xFF3067B657990C3AULL,
315 	0x711223CFA3E5BB50ULL, 0x33E2C2240A0F8DC3ULL, 0xF4F3E018F031D676ULL,
316 	0xB60301F359DBE0E5ULL, 0xDA050215EA6C212FULL, 0x98F5E3FE438617BCULL,
317 	0x5FE4C1C2B9B84C09ULL, 0x1D14202910527A9AULL, 0x93366450E42ECDF0ULL,
318 	0xD1C685BB4DC4FB63ULL, 0x16D7A787B7FAA0D6ULL, 0x5427466C1E109645ULL,
319 	0x4863CE9FF6E9F891ULL, 0x0A932F745F03CE02ULL, 0xCD820D48A53D95B7ULL,
320 	0x8F72ECA30CD7A324ULL, 0x0150A8DAF8AB144EULL, 0x43A04931514122DDULL,
321 	0x84B16B0DAB7F7968ULL, 0xC6418AE602954FFBULL, 0xBC387AEA7A8DA4C0ULL,
322 	0xFEC89B01D3679253ULL, 0x39D9B93D2959C9E6ULL, 0x7B2958D680B3FF75ULL,
323 	0xF50B1CAF74CF481FULL, 0xB7FBFD44DD257E8CULL, 0x70EADF78271B2539ULL,
324 	0x321A3E938EF113AAULL, 0x2E5EB66066087D7EULL, 0x6CAE578BCFE24BEDULL,
325 	0xABBF75B735DC1058ULL, 0xE94F945C9C3626CBULL, 0x676DD025684A91A1ULL,
326 	0x259D31CEC1A0A732ULL, 0xE28C13F23B9EFC87ULL, 0xA07CF2199274CA14ULL,
327 	0x167FF3EACBAF2AF1ULL, 0x548F120162451C62ULL, 0x939E303D987B47D7ULL,
328 	0xD16ED1D631917144ULL, 0x5F4C95AFC5EDC62EULL, 0x1DBC74446C07F0BDULL,
329 	0xDAAD56789639AB08ULL, 0x985DB7933FD39D9BULL, 0x84193F60D72AF34FULL,
330 	0xC6E9DE8B7EC0C5DCULL, 0x01F8FCB784FE9E69ULL, 0x43081D5C2D14A8FAULL,
331 	0xCD2A5925D9681F90ULL, 0x8FDAB8CE70822903ULL, 0x48CB9AF28ABC72B6ULL,
332 	0x0A3B7B1923564425ULL, 0x70428B155B4EAF1EULL, 0x32B26AFEF2A4998DULL,
333 	0xF5A348C2089AC238ULL, 0xB753A929A170F4ABULL, 0x3971ED50550C43C1ULL,
334 	0x7B810CBBFCE67552ULL, 0xBC902E8706D82EE7ULL, 0xFE60CF6CAF321874ULL,
335 	0xE224479F47CB76A0ULL, 0xA0D4A674EE214033ULL, 0x67C58448141F1B86ULL,
336 	0x253565A3BDF52D15ULL, 0xAB1721DA49899A7FULL, 0xE9E7C031E063ACECULL,
337 	0x2EF6E20D1A5DF759ULL, 0x6C0603E6B3B7C1CAULL, 0xF6FAE5C07D3274CDULL,
338 	0xB40A042BD4D8425EULL, 0x731B26172EE619EBULL, 0x31EBC7FC870C2F78ULL,
339 	0xBFC9838573709812ULL, 0xFD39626EDA9AAE81ULL, 0x3A28405220A4F534ULL,
340 	0x78D8A1B9894EC3A7ULL, 0x649C294A61B7AD73ULL, 0x266CC8A1C85D9BE0ULL,
341 	0xE17DEA9D3263C055ULL, 0xA38D0B769B89F6C6ULL, 0x2DAF4F0F6FF541ACULL,
342 	0x6F5FAEE4C61F773FULL, 0xA84E8CD83C212C8AULL, 0xEABE6D3395CB1A19ULL,
343 	0x90C79D3FEDD3F122ULL, 0xD2377CD44439C7B1ULL, 0x15265EE8BE079C04ULL,
344 	0x57D6BF0317EDAA97ULL, 0xD9F4FB7AE3911DFDULL, 0x9B041A914A7B2B6EULL,
345 	0x5C1538ADB04570DBULL, 0x1EE5D94619AF4648ULL, 0x02A151B5F156289CULL,
346 	0x4051B05E58BC1E0FULL, 0x87409262A28245BAULL, 0xC5B073890B687329ULL,
347 	0x4B9237F0FF14C443ULL, 0x0962D61B56FEF2D0ULL, 0xCE73F427ACC0A965ULL,
348 	0x8C8315CC052A9FF6ULL, 0x3A80143F5CF17F13ULL, 0x7870F5D4F51B4980ULL,
349 	0xBF61D7E80F251235ULL, 0xFD913603A6CF24A6ULL, 0x73B3727A52B393CCULL,
350 	0x31439391FB59A55FULL, 0xF652B1AD0167FEEAULL, 0xB4A25046A88DC879ULL,
351 	0xA8E6D8B54074A6ADULL, 0xEA16395EE99E903EULL, 0x2D071B6213A0CB8BULL,
352 	0x6FF7FA89BA4AFD18ULL, 0xE1D5BEF04E364A72ULL, 0xA3255F1BE7DC7CE1ULL,
353 	0x64347D271DE22754ULL, 0x26C49CCCB40811C7ULL, 0x5CBD6CC0CC10FAFCULL,
354 	0x1E4D8D2B65FACC6FULL, 0xD95CAF179FC497DAULL, 0x9BAC4EFC362EA149ULL,
355 	0x158E0A85C2521623ULL, 0x577EEB6E6BB820B0ULL, 0x906FC95291867B05ULL,
356 	0xD29F28B9386C4D96ULL, 0xCEDBA04AD0952342ULL, 0x8C2B41A1797F15D1ULL,
357 	0x4B3A639D83414E64ULL, 0x09CA82762AAB78F7ULL, 0x87E8C60FDED7CF9DULL,
358 	0xC51827E4773DF90EULL, 0x020905D88D03A2BBULL, 0x40F9E43324E99428ULL,
359 	0x2CFFE7D5975E55E2ULL, 0x6E0F063E3EB46371ULL, 0xA91E2402C48A38C4ULL,
360 	0xEBEEC5E96D600E57ULL, 0x65CC8190991CB93DULL, 0x273C607B30F68FAEULL,
361 	0xE02D4247CAC8D41BULL, 0xA2DDA3AC6322E288ULL, 0xBE992B5F8BDB8C5CULL,
362 	0xFC69CAB42231BACFULL, 0x3B78E888D80FE17AULL, 0x7988096371E5D7E9ULL,
363 	0xF7AA4D1A85996083ULL, 0xB55AACF12C735610ULL, 0x724B8ECDD64D0DA5ULL,
364 	0x30BB6F267FA73B36ULL, 0x4AC29F2A07BFD00DULL, 0x08327EC1AE55E69EULL,
365 	0xCF235CFD546BBD2BULL, 0x8DD3BD16FD818BB8ULL, 0x03F1F96F09FD3CD2ULL,
366 	0x41011884A0170A41ULL, 0x86103AB85A2951F4ULL, 0xC4E0DB53F3C36767ULL,
367 	0xD8A453A01B3A09B3ULL, 0x9A54B24BB2D03F20ULL, 0x5D45907748EE6495ULL,
368 	0x1FB5719CE1045206ULL, 0x919735E51578E56CULL, 0xD367D40EBC92D3FFULL,
369 	0x1476F63246AC884AULL, 0x568617D9EF46BED9ULL, 0xE085162AB69D5E3CULL,
370 	0xA275F7C11F7768AFULL, 0x6564D5FDE549331AULL, 0x279434164CA30589ULL,
371 	0xA9B6706FB8DFB2E3ULL, 0xEB46918411358470ULL, 0x2C57B3B8EB0BDFC5ULL,
372 	0x6EA7525342E1E956ULL, 0x72E3DAA0AA188782ULL, 0x30133B4B03F2B111ULL,
373 	0xF7021977F9CCEAA4ULL, 0xB5F2F89C5026DC37ULL, 0x3BD0BCE5A45A6B5DULL,
374 	0x79205D0E0DB05DCEULL, 0xBE317F32F78E067BULL, 0xFCC19ED95E6430E8ULL,
375 	0x86B86ED5267CDBD3ULL, 0xC4488F3E8F96ED40ULL, 0x0359AD0275A8B6F5ULL,
376 	0x41A94CE9DC428066ULL, 0xCF8B0890283E370CULL, 0x8D7BE97B81D4019FULL,
377 	0x4A6ACB477BEA5A2AULL, 0x089A2AACD2006CB9ULL, 0x14DEA25F3AF9026DULL,
378 	0x562E43B4931334FEULL, 0x913F6188692D6F4BULL, 0xD3CF8063C0C759D8ULL,
379 	0x5DEDC41A34BBEEB2ULL, 0x1F1D25F19D51D821ULL, 0xD80C07CD676F8394ULL,
380 	0x9AFCE626CE85B507ULL,
381 };
382 
383 uint64_t bch_crc64_update(uint64_t crc, const void *_data, size_t len)
384 {
385 	const unsigned char *data = _data;
386 
387 	while (len--) {
388 		int i = ((int) (crc >> 56) ^ *data++) & 0xFF;
389 		crc = crc_table[i] ^ (crc << 8);
390 	}
391 
392 	return crc;
393 }
394 
395 uint64_t bch_crc64(const void *data, size_t len)
396 {
397 	uint64_t crc = 0xffffffffffffffffULL;
398 
399 	crc = bch_crc64_update(crc, data, len);
400 
401 	return crc ^ 0xffffffffffffffffULL;
402 }
403