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