1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * random utiility code, for bcache but in theory not specific to bcache 4 * 5 * Copyright 2010, 2011 Kent Overstreet <[email protected]> 6 * Copyright 2012 Google, Inc. 7 */ 8 9 #include <linux/bio.h> 10 #include <linux/blkdev.h> 11 #include <linux/ctype.h> 12 #include <linux/debugfs.h> 13 #include <linux/module.h> 14 #include <linux/seq_file.h> 15 #include <linux/types.h> 16 #include <linux/sched/clock.h> 17 18 #include "util.h" 19 20 #define simple_strtoint(c, end, base) simple_strtol(c, end, base) 21 #define simple_strtouint(c, end, base) simple_strtoul(c, end, base) 22 23 #define STRTO_H(name, type) \ 24 int bch_ ## name ## _h(const char *cp, type *res) \ 25 { \ 26 int u = 0; \ 27 char *e; \ 28 type i = simple_ ## name(cp, &e, 10); \ 29 \ 30 switch (tolower(*e)) { \ 31 default: \ 32 return -EINVAL; \ 33 case 'y': \ 34 case 'z': \ 35 u++; \ 36 /* fall through */ \ 37 case 'e': \ 38 u++; \ 39 /* fall through */ \ 40 case 'p': \ 41 u++; \ 42 /* fall through */ \ 43 case 't': \ 44 u++; \ 45 /* fall through */ \ 46 case 'g': \ 47 u++; \ 48 /* fall through */ \ 49 case 'm': \ 50 u++; \ 51 /* fall through */ \ 52 case 'k': \ 53 u++; \ 54 if (e++ == cp) \ 55 return -EINVAL; \ 56 /* fall through */ \ 57 case '\n': \ 58 case '\0': \ 59 if (*e == '\n') \ 60 e++; \ 61 } \ 62 \ 63 if (*e) \ 64 return -EINVAL; \ 65 \ 66 while (u--) { \ 67 if ((type) ~0 > 0 && \ 68 (type) ~0 / 1024 <= i) \ 69 return -EINVAL; \ 70 if ((i > 0 && ANYSINT_MAX(type) / 1024 < i) || \ 71 (i < 0 && -ANYSINT_MAX(type) / 1024 > i)) \ 72 return -EINVAL; \ 73 i *= 1024; \ 74 } \ 75 \ 76 *res = i; \ 77 return 0; \ 78 } \ 79 80 STRTO_H(strtoint, int) 81 STRTO_H(strtouint, unsigned int) 82 STRTO_H(strtoll, long long) 83 STRTO_H(strtoull, unsigned long long) 84 85 /** 86 * bch_hprint - formats @v to human readable string for sysfs. 87 * @buf: the (at least 8 byte) buffer to format the result into. 88 * @v: signed 64 bit integer 89 * 90 * Returns the number of bytes used by format. 91 */ 92 ssize_t bch_hprint(char *buf, int64_t v) 93 { 94 static const char units[] = "?kMGTPEZY"; 95 int u = 0, t; 96 97 uint64_t q; 98 99 if (v < 0) 100 q = -v; 101 else 102 q = v; 103 104 /* For as long as the number is more than 3 digits, but at least 105 * once, shift right / divide by 1024. Keep the remainder for 106 * a digit after the decimal point. 107 */ 108 do { 109 u++; 110 111 t = q & ~(~0 << 10); 112 q >>= 10; 113 } while (q >= 1000); 114 115 if (v < 0) 116 /* '-', up to 3 digits, '.', 1 digit, 1 character, null; 117 * yields 8 bytes. 118 */ 119 return sprintf(buf, "-%llu.%i%c", q, t * 10 / 1024, units[u]); 120 else 121 return sprintf(buf, "%llu.%i%c", q, t * 10 / 1024, units[u]); 122 } 123 124 bool bch_is_zero(const char *p, size_t n) 125 { 126 size_t i; 127 128 for (i = 0; i < n; i++) 129 if (p[i]) 130 return false; 131 return true; 132 } 133 134 int bch_parse_uuid(const char *s, char *uuid) 135 { 136 size_t i, j, x; 137 138 memset(uuid, 0, 16); 139 140 for (i = 0, j = 0; 141 i < strspn(s, "-0123456789:ABCDEFabcdef") && j < 32; 142 i++) { 143 x = s[i] | 32; 144 145 switch (x) { 146 case '0'...'9': 147 x -= '0'; 148 break; 149 case 'a'...'f': 150 x -= 'a' - 10; 151 break; 152 default: 153 continue; 154 } 155 156 if (!(j & 1)) 157 x <<= 4; 158 uuid[j++ >> 1] |= x; 159 } 160 return i; 161 } 162 163 void bch_time_stats_update(struct time_stats *stats, uint64_t start_time) 164 { 165 uint64_t now, duration, last; 166 167 spin_lock(&stats->lock); 168 169 now = local_clock(); 170 duration = time_after64(now, start_time) 171 ? now - start_time : 0; 172 last = time_after64(now, stats->last) 173 ? now - stats->last : 0; 174 175 stats->max_duration = max(stats->max_duration, duration); 176 177 if (stats->last) { 178 ewma_add(stats->average_duration, duration, 8, 8); 179 180 if (stats->average_frequency) 181 ewma_add(stats->average_frequency, last, 8, 8); 182 else 183 stats->average_frequency = last << 8; 184 } else { 185 stats->average_duration = duration << 8; 186 } 187 188 stats->last = now ?: 1; 189 190 spin_unlock(&stats->lock); 191 } 192 193 /** 194 * bch_next_delay() - update ratelimiting statistics and calculate next delay 195 * @d: the struct bch_ratelimit to update 196 * @done: the amount of work done, in arbitrary units 197 * 198 * Increment @d by the amount of work done, and return how long to delay in 199 * jiffies until the next time to do some work. 200 */ 201 uint64_t bch_next_delay(struct bch_ratelimit *d, uint64_t done) 202 { 203 uint64_t now = local_clock(); 204 205 d->next += div_u64(done * NSEC_PER_SEC, atomic_long_read(&d->rate)); 206 207 /* Bound the time. Don't let us fall further than 2 seconds behind 208 * (this prevents unnecessary backlog that would make it impossible 209 * to catch up). If we're ahead of the desired writeback rate, 210 * don't let us sleep more than 2.5 seconds (so we can notice/respond 211 * if the control system tells us to speed up!). 212 */ 213 if (time_before64(now + NSEC_PER_SEC * 5LLU / 2LLU, d->next)) 214 d->next = now + NSEC_PER_SEC * 5LLU / 2LLU; 215 216 if (time_after64(now - NSEC_PER_SEC * 2, d->next)) 217 d->next = now - NSEC_PER_SEC * 2; 218 219 return time_after64(d->next, now) 220 ? div_u64(d->next - now, NSEC_PER_SEC / HZ) 221 : 0; 222 } 223 224 /* 225 * Generally it isn't good to access .bi_io_vec and .bi_vcnt directly, 226 * the preferred way is bio_add_page, but in this case, bch_bio_map() 227 * supposes that the bvec table is empty, so it is safe to access 228 * .bi_vcnt & .bi_io_vec in this way even after multipage bvec is 229 * supported. 230 */ 231 void bch_bio_map(struct bio *bio, void *base) 232 { 233 size_t size = bio->bi_iter.bi_size; 234 struct bio_vec *bv = bio->bi_io_vec; 235 236 BUG_ON(!bio->bi_iter.bi_size); 237 BUG_ON(bio->bi_vcnt); 238 239 bv->bv_offset = base ? offset_in_page(base) : 0; 240 goto start; 241 242 for (; size; bio->bi_vcnt++, bv++) { 243 bv->bv_offset = 0; 244 start: bv->bv_len = min_t(size_t, PAGE_SIZE - bv->bv_offset, 245 size); 246 if (base) { 247 bv->bv_page = is_vmalloc_addr(base) 248 ? vmalloc_to_page(base) 249 : virt_to_page(base); 250 251 base += bv->bv_len; 252 } 253 254 size -= bv->bv_len; 255 } 256 } 257 258 /** 259 * bch_bio_alloc_pages - allocates a single page for each bvec in a bio 260 * @bio: bio to allocate pages for 261 * @gfp_mask: flags for allocation 262 * 263 * Allocates pages up to @bio->bi_vcnt. 264 * 265 * Returns 0 on success, -ENOMEM on failure. On failure, any allocated pages are 266 * freed. 267 */ 268 int bch_bio_alloc_pages(struct bio *bio, gfp_t gfp_mask) 269 { 270 int i; 271 struct bio_vec *bv; 272 273 bio_for_each_segment_all(bv, bio, i) { 274 bv->bv_page = alloc_page(gfp_mask); 275 if (!bv->bv_page) { 276 while (--bv >= bio->bi_io_vec) 277 __free_page(bv->bv_page); 278 return -ENOMEM; 279 } 280 } 281 282 return 0; 283 } 284 285 /* 286 * Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group (Any 287 * use permitted, subject to terms of PostgreSQL license; see.) 288 289 * If we have a 64-bit integer type, then a 64-bit CRC looks just like the 290 * usual sort of implementation. (See Ross Williams' excellent introduction 291 * A PAINLESS GUIDE TO CRC ERROR DETECTION ALGORITHMS, available from 292 * ftp://ftp.rocksoft.com/papers/crc_v3.txt or several other net sites.) 293 * If we have no working 64-bit type, then fake it with two 32-bit registers. 294 * 295 * The present implementation is a normal (not "reflected", in Williams' 296 * terms) 64-bit CRC, using initial all-ones register contents and a final 297 * bit inversion. The chosen polynomial is borrowed from the DLT1 spec 298 * (ECMA-182, available from http://www.ecma.ch/ecma1/STAND/ECMA-182.HTM): 299 * 300 * x^64 + x^62 + x^57 + x^55 + x^54 + x^53 + x^52 + x^47 + x^46 + x^45 + 301 * x^40 + x^39 + x^38 + x^37 + x^35 + x^33 + x^32 + x^31 + x^29 + x^27 + 302 * x^24 + x^23 + x^22 + x^21 + x^19 + x^17 + x^13 + x^12 + x^10 + x^9 + 303 * x^7 + x^4 + x + 1 304 */ 305 306 static const uint64_t crc_table[256] = { 307 0x0000000000000000ULL, 0x42F0E1EBA9EA3693ULL, 0x85E1C3D753D46D26ULL, 308 0xC711223CFA3E5BB5ULL, 0x493366450E42ECDFULL, 0x0BC387AEA7A8DA4CULL, 309 0xCCD2A5925D9681F9ULL, 0x8E224479F47CB76AULL, 0x9266CC8A1C85D9BEULL, 310 0xD0962D61B56FEF2DULL, 0x17870F5D4F51B498ULL, 0x5577EEB6E6BB820BULL, 311 0xDB55AACF12C73561ULL, 0x99A54B24BB2D03F2ULL, 0x5EB4691841135847ULL, 312 0x1C4488F3E8F96ED4ULL, 0x663D78FF90E185EFULL, 0x24CD9914390BB37CULL, 313 0xE3DCBB28C335E8C9ULL, 0xA12C5AC36ADFDE5AULL, 0x2F0E1EBA9EA36930ULL, 314 0x6DFEFF5137495FA3ULL, 0xAAEFDD6DCD770416ULL, 0xE81F3C86649D3285ULL, 315 0xF45BB4758C645C51ULL, 0xB6AB559E258E6AC2ULL, 0x71BA77A2DFB03177ULL, 316 0x334A9649765A07E4ULL, 0xBD68D2308226B08EULL, 0xFF9833DB2BCC861DULL, 317 0x388911E7D1F2DDA8ULL, 0x7A79F00C7818EB3BULL, 0xCC7AF1FF21C30BDEULL, 318 0x8E8A101488293D4DULL, 0x499B3228721766F8ULL, 0x0B6BD3C3DBFD506BULL, 319 0x854997BA2F81E701ULL, 0xC7B97651866BD192ULL, 0x00A8546D7C558A27ULL, 320 0x4258B586D5BFBCB4ULL, 0x5E1C3D753D46D260ULL, 0x1CECDC9E94ACE4F3ULL, 321 0xDBFDFEA26E92BF46ULL, 0x990D1F49C77889D5ULL, 0x172F5B3033043EBFULL, 322 0x55DFBADB9AEE082CULL, 0x92CE98E760D05399ULL, 0xD03E790CC93A650AULL, 323 0xAA478900B1228E31ULL, 0xE8B768EB18C8B8A2ULL, 0x2FA64AD7E2F6E317ULL, 324 0x6D56AB3C4B1CD584ULL, 0xE374EF45BF6062EEULL, 0xA1840EAE168A547DULL, 325 0x66952C92ECB40FC8ULL, 0x2465CD79455E395BULL, 0x3821458AADA7578FULL, 326 0x7AD1A461044D611CULL, 0xBDC0865DFE733AA9ULL, 0xFF3067B657990C3AULL, 327 0x711223CFA3E5BB50ULL, 0x33E2C2240A0F8DC3ULL, 0xF4F3E018F031D676ULL, 328 0xB60301F359DBE0E5ULL, 0xDA050215EA6C212FULL, 0x98F5E3FE438617BCULL, 329 0x5FE4C1C2B9B84C09ULL, 0x1D14202910527A9AULL, 0x93366450E42ECDF0ULL, 330 0xD1C685BB4DC4FB63ULL, 0x16D7A787B7FAA0D6ULL, 0x5427466C1E109645ULL, 331 0x4863CE9FF6E9F891ULL, 0x0A932F745F03CE02ULL, 0xCD820D48A53D95B7ULL, 332 0x8F72ECA30CD7A324ULL, 0x0150A8DAF8AB144EULL, 0x43A04931514122DDULL, 333 0x84B16B0DAB7F7968ULL, 0xC6418AE602954FFBULL, 0xBC387AEA7A8DA4C0ULL, 334 0xFEC89B01D3679253ULL, 0x39D9B93D2959C9E6ULL, 0x7B2958D680B3FF75ULL, 335 0xF50B1CAF74CF481FULL, 0xB7FBFD44DD257E8CULL, 0x70EADF78271B2539ULL, 336 0x321A3E938EF113AAULL, 0x2E5EB66066087D7EULL, 0x6CAE578BCFE24BEDULL, 337 0xABBF75B735DC1058ULL, 0xE94F945C9C3626CBULL, 0x676DD025684A91A1ULL, 338 0x259D31CEC1A0A732ULL, 0xE28C13F23B9EFC87ULL, 0xA07CF2199274CA14ULL, 339 0x167FF3EACBAF2AF1ULL, 0x548F120162451C62ULL, 0x939E303D987B47D7ULL, 340 0xD16ED1D631917144ULL, 0x5F4C95AFC5EDC62EULL, 0x1DBC74446C07F0BDULL, 341 0xDAAD56789639AB08ULL, 0x985DB7933FD39D9BULL, 0x84193F60D72AF34FULL, 342 0xC6E9DE8B7EC0C5DCULL, 0x01F8FCB784FE9E69ULL, 0x43081D5C2D14A8FAULL, 343 0xCD2A5925D9681F90ULL, 0x8FDAB8CE70822903ULL, 0x48CB9AF28ABC72B6ULL, 344 0x0A3B7B1923564425ULL, 0x70428B155B4EAF1EULL, 0x32B26AFEF2A4998DULL, 345 0xF5A348C2089AC238ULL, 0xB753A929A170F4ABULL, 0x3971ED50550C43C1ULL, 346 0x7B810CBBFCE67552ULL, 0xBC902E8706D82EE7ULL, 0xFE60CF6CAF321874ULL, 347 0xE224479F47CB76A0ULL, 0xA0D4A674EE214033ULL, 0x67C58448141F1B86ULL, 348 0x253565A3BDF52D15ULL, 0xAB1721DA49899A7FULL, 0xE9E7C031E063ACECULL, 349 0x2EF6E20D1A5DF759ULL, 0x6C0603E6B3B7C1CAULL, 0xF6FAE5C07D3274CDULL, 350 0xB40A042BD4D8425EULL, 0x731B26172EE619EBULL, 0x31EBC7FC870C2F78ULL, 351 0xBFC9838573709812ULL, 0xFD39626EDA9AAE81ULL, 0x3A28405220A4F534ULL, 352 0x78D8A1B9894EC3A7ULL, 0x649C294A61B7AD73ULL, 0x266CC8A1C85D9BE0ULL, 353 0xE17DEA9D3263C055ULL, 0xA38D0B769B89F6C6ULL, 0x2DAF4F0F6FF541ACULL, 354 0x6F5FAEE4C61F773FULL, 0xA84E8CD83C212C8AULL, 0xEABE6D3395CB1A19ULL, 355 0x90C79D3FEDD3F122ULL, 0xD2377CD44439C7B1ULL, 0x15265EE8BE079C04ULL, 356 0x57D6BF0317EDAA97ULL, 0xD9F4FB7AE3911DFDULL, 0x9B041A914A7B2B6EULL, 357 0x5C1538ADB04570DBULL, 0x1EE5D94619AF4648ULL, 0x02A151B5F156289CULL, 358 0x4051B05E58BC1E0FULL, 0x87409262A28245BAULL, 0xC5B073890B687329ULL, 359 0x4B9237F0FF14C443ULL, 0x0962D61B56FEF2D0ULL, 0xCE73F427ACC0A965ULL, 360 0x8C8315CC052A9FF6ULL, 0x3A80143F5CF17F13ULL, 0x7870F5D4F51B4980ULL, 361 0xBF61D7E80F251235ULL, 0xFD913603A6CF24A6ULL, 0x73B3727A52B393CCULL, 362 0x31439391FB59A55FULL, 0xF652B1AD0167FEEAULL, 0xB4A25046A88DC879ULL, 363 0xA8E6D8B54074A6ADULL, 0xEA16395EE99E903EULL, 0x2D071B6213A0CB8BULL, 364 0x6FF7FA89BA4AFD18ULL, 0xE1D5BEF04E364A72ULL, 0xA3255F1BE7DC7CE1ULL, 365 0x64347D271DE22754ULL, 0x26C49CCCB40811C7ULL, 0x5CBD6CC0CC10FAFCULL, 366 0x1E4D8D2B65FACC6FULL, 0xD95CAF179FC497DAULL, 0x9BAC4EFC362EA149ULL, 367 0x158E0A85C2521623ULL, 0x577EEB6E6BB820B0ULL, 0x906FC95291867B05ULL, 368 0xD29F28B9386C4D96ULL, 0xCEDBA04AD0952342ULL, 0x8C2B41A1797F15D1ULL, 369 0x4B3A639D83414E64ULL, 0x09CA82762AAB78F7ULL, 0x87E8C60FDED7CF9DULL, 370 0xC51827E4773DF90EULL, 0x020905D88D03A2BBULL, 0x40F9E43324E99428ULL, 371 0x2CFFE7D5975E55E2ULL, 0x6E0F063E3EB46371ULL, 0xA91E2402C48A38C4ULL, 372 0xEBEEC5E96D600E57ULL, 0x65CC8190991CB93DULL, 0x273C607B30F68FAEULL, 373 0xE02D4247CAC8D41BULL, 0xA2DDA3AC6322E288ULL, 0xBE992B5F8BDB8C5CULL, 374 0xFC69CAB42231BACFULL, 0x3B78E888D80FE17AULL, 0x7988096371E5D7E9ULL, 375 0xF7AA4D1A85996083ULL, 0xB55AACF12C735610ULL, 0x724B8ECDD64D0DA5ULL, 376 0x30BB6F267FA73B36ULL, 0x4AC29F2A07BFD00DULL, 0x08327EC1AE55E69EULL, 377 0xCF235CFD546BBD2BULL, 0x8DD3BD16FD818BB8ULL, 0x03F1F96F09FD3CD2ULL, 378 0x41011884A0170A41ULL, 0x86103AB85A2951F4ULL, 0xC4E0DB53F3C36767ULL, 379 0xD8A453A01B3A09B3ULL, 0x9A54B24BB2D03F20ULL, 0x5D45907748EE6495ULL, 380 0x1FB5719CE1045206ULL, 0x919735E51578E56CULL, 0xD367D40EBC92D3FFULL, 381 0x1476F63246AC884AULL, 0x568617D9EF46BED9ULL, 0xE085162AB69D5E3CULL, 382 0xA275F7C11F7768AFULL, 0x6564D5FDE549331AULL, 0x279434164CA30589ULL, 383 0xA9B6706FB8DFB2E3ULL, 0xEB46918411358470ULL, 0x2C57B3B8EB0BDFC5ULL, 384 0x6EA7525342E1E956ULL, 0x72E3DAA0AA188782ULL, 0x30133B4B03F2B111ULL, 385 0xF7021977F9CCEAA4ULL, 0xB5F2F89C5026DC37ULL, 0x3BD0BCE5A45A6B5DULL, 386 0x79205D0E0DB05DCEULL, 0xBE317F32F78E067BULL, 0xFCC19ED95E6430E8ULL, 387 0x86B86ED5267CDBD3ULL, 0xC4488F3E8F96ED40ULL, 0x0359AD0275A8B6F5ULL, 388 0x41A94CE9DC428066ULL, 0xCF8B0890283E370CULL, 0x8D7BE97B81D4019FULL, 389 0x4A6ACB477BEA5A2AULL, 0x089A2AACD2006CB9ULL, 0x14DEA25F3AF9026DULL, 390 0x562E43B4931334FEULL, 0x913F6188692D6F4BULL, 0xD3CF8063C0C759D8ULL, 391 0x5DEDC41A34BBEEB2ULL, 0x1F1D25F19D51D821ULL, 0xD80C07CD676F8394ULL, 392 0x9AFCE626CE85B507ULL, 393 }; 394 395 uint64_t bch_crc64_update(uint64_t crc, const void *_data, size_t len) 396 { 397 const unsigned char *data = _data; 398 399 while (len--) { 400 int i = ((int) (crc >> 56) ^ *data++) & 0xFF; 401 crc = crc_table[i] ^ (crc << 8); 402 } 403 404 return crc; 405 } 406 407 uint64_t bch_crc64(const void *data, size_t len) 408 { 409 uint64_t crc = 0xffffffffffffffffULL; 410 411 crc = bch_crc64_update(crc, data, len); 412 413 return crc ^ 0xffffffffffffffffULL; 414 } 415