drivers/md/bcache/util.c

   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 }