drivers/md/bcache/util.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2
   3 #ifndef _BCACHE_UTIL_H
   4 #define _BCACHE_UTIL_H
   5
   6 #include <linux/blkdev.h>
   7 #include <linux/errno.h>
   8 #include <linux/kernel.h>
   9 #include <linux/sched/clock.h>
  10 #include <linux/llist.h>
  11 #include <linux/ratelimit.h>
  12 #include <linux/vmalloc.h>
  13 #include <linux/workqueue.h>
  14 #include <linux/crc64.h>
  15
  16 #include "closure.h"
  17
  18 struct closure;
  19
  20 #ifdef CONFIG_BCACHE_DEBUG
  21
  22 #define EBUG_ON(cond)                   BUG_ON(cond)
  23 #define atomic_dec_bug(v)       BUG_ON(atomic_dec_return(v) < 0)
  24 #define atomic_inc_bug(v, i)    BUG_ON(atomic_inc_return(v) <= i)
  25
  26 #else /* DEBUG */
  27
  28 #define EBUG_ON(cond)           do { if (cond) do {} while (0); } while (0)
  29 #define atomic_dec_bug(v)       atomic_dec(v)
  30 #define atomic_inc_bug(v, i)    atomic_inc(v)
  31
  32 #endif
  33
  34 #define DECLARE_HEAP(type, name)                                        \
  35         struct {                                                        \
  36                 size_t size, used;                                      \
  37                 type *data;                                             \
  38         } name
  39
  40 #define init_heap(heap, _size, gfp)                                     \
  41 ({                                                                      \
  42         size_t _bytes;                                                  \
  43         (heap)->used = 0;                                               \
  44         (heap)->size = (_size);                                         \
  45         _bytes = (heap)->size * sizeof(*(heap)->data);                  \
  46         (heap)->data = kvmalloc(_bytes, (gfp) & GFP_KERNEL);            \
  47         (heap)->data;                                                   \
  48 })
  49
  50 #define free_heap(heap)                                                 \
  51 do {                                                                    \
  52         kvfree((heap)->data);                                           \
  53         (heap)->data = NULL;                                            \
  54 } while (0)
  55
  56 #define heap_swap(h, i, j)      swap((h)->data[i], (h)->data[j])
  57
  58 #define heap_sift(h, i, cmp)                                            \
  59 do {                                                                    \
  60         size_t _r, _j = i;                                              \
  61                                                                         \
  62         for (; _j * 2 + 1 < (h)->used; _j = _r) {                       \
  63                 _r = _j * 2 + 1;                                        \
  64                 if (_r + 1 < (h)->used &&                               \
  65                     cmp((h)->data[_r], (h)->data[_r + 1]))              \
  66                         _r++;                                           \
  67                                                                         \
  68                 if (cmp((h)->data[_r], (h)->data[_j]))                  \
  69                         break;                                          \
  70                 heap_swap(h, _r, _j);                                   \
  71         }                                                               \
  72 } while (0)
  73
  74 #define heap_sift_down(h, i, cmp)                                       \
  75 do {                                                                    \
  76         while (i) {                                                     \
  77                 size_t p = (i - 1) / 2;                                 \
  78                 if (cmp((h)->data[i], (h)->data[p]))                    \
  79                         break;                                          \
  80                 heap_swap(h, i, p);                                     \
  81                 i = p;                                                  \
  82         }                                                               \
  83 } while (0)
  84
  85 #define heap_add(h, d, cmp)                                             \
  86 ({                                                                      \
  87         bool _r = !heap_full(h);                                        \
  88         if (_r) {                                                       \
  89                 size_t _i = (h)->used++;                                \
  90                 (h)->data[_i] = d;                                      \
  91                                                                         \
  92                 heap_sift_down(h, _i, cmp);                             \
  93                 heap_sift(h, _i, cmp);                                  \
  94         }                                                               \
  95         _r;                                                             \
  96 })
  97
  98 #define heap_pop(h, d, cmp)                                             \
  99 ({                                                                      \
 100         bool _r = (h)->used;                                            \
 101         if (_r) {                                                       \
 102                 (d) = (h)->data[0];                                     \
 103                 (h)->used--;                                            \
 104                 heap_swap(h, 0, (h)->used);                             \
 105                 heap_sift(h, 0, cmp);                                   \
 106         }                                                               \
 107         _r;                                                             \
 108 })
 109
 110 #define heap_peek(h)    ((h)->used ? (h)->data[0] : NULL)
 111
 112 #define heap_full(h)    ((h)->used == (h)->size)
 113
 114 #define DECLARE_FIFO(type, name)                                        \
 115         struct {                                                        \
 116                 size_t front, back, size, mask;                         \
 117                 type *data;                                             \
 118         } name
 119
 120 #define fifo_for_each(c, fifo, iter)                                    \
 121         for (iter = (fifo)->front;                                      \
 122              c = (fifo)->data[iter], iter != (fifo)->back;              \
 123              iter = (iter + 1) & (fifo)->mask)
 124
 125 #define __init_fifo(fifo, gfp)                                          \
 126 ({                                                                      \
 127         size_t _allocated_size, _bytes;                                 \
 128         BUG_ON(!(fifo)->size);                                          \
 129                                                                         \
 130         _allocated_size = roundup_pow_of_two((fifo)->size + 1);         \
 131         _bytes = _allocated_size * sizeof(*(fifo)->data);               \
 132                                                                         \
 133         (fifo)->mask = _allocated_size - 1;                             \
 134         (fifo)->front = (fifo)->back = 0;                               \
 135                                                                         \
 136         (fifo)->data = kvmalloc(_bytes, (gfp) & GFP_KERNEL);            \
 137         (fifo)->data;                                                   \
 138 })
 139
 140 #define init_fifo_exact(fifo, _size, gfp)                               \
 141 ({                                                                      \
 142         (fifo)->size = (_size);                                         \
 143         __init_fifo(fifo, gfp);                                         \
 144 })
 145
 146 #define init_fifo(fifo, _size, gfp)                                     \
 147 ({                                                                      \
 148         (fifo)->size = (_size);                                         \
 149         if ((fifo)->size > 4)                                           \
 150                 (fifo)->size = roundup_pow_of_two((fifo)->size) - 1;    \
 151         __init_fifo(fifo, gfp);                                         \
 152 })
 153
 154 #define free_fifo(fifo)                                                 \
 155 do {                                                                    \
 156         kvfree((fifo)->data);                                           \
 157         (fifo)->data = NULL;                                            \
 158 } while (0)
 159
 160 #define fifo_used(fifo)         (((fifo)->back - (fifo)->front) & (fifo)->mask)
 161 #define fifo_free(fifo)         ((fifo)->size - fifo_used(fifo))
 162
 163 #define fifo_empty(fifo)        (!fifo_used(fifo))
 164 #define fifo_full(fifo)         (!fifo_free(fifo))
 165
 166 #define fifo_front(fifo)        ((fifo)->data[(fifo)->front])
 167 #define fifo_back(fifo)                                                 \
 168         ((fifo)->data[((fifo)->back - 1) & (fifo)->mask])
 169
 170 #define fifo_idx(fifo, p)       (((p) - &fifo_front(fifo)) & (fifo)->mask)
 171
 172 #define fifo_push_back(fifo, i)                                         \
 173 ({                                                                      \
 174         bool _r = !fifo_full((fifo));                                   \
 175         if (_r) {                                                       \
 176                 (fifo)->data[(fifo)->back++] = (i);                     \
 177                 (fifo)->back &= (fifo)->mask;                           \
 178         }                                                               \
 179         _r;                                                             \
 180 })
 181
 182 #define fifo_pop_front(fifo, i)                                         \
 183 ({                                                                      \
 184         bool _r = !fifo_empty((fifo));                                  \
 185         if (_r) {                                                       \
 186                 (i) = (fifo)->data[(fifo)->front++];                    \
 187                 (fifo)->front &= (fifo)->mask;                          \
 188         }                                                               \
 189         _r;                                                             \
 190 })
 191
 192 #define fifo_push_front(fifo, i)                                        \
 193 ({                                                                      \
 194         bool _r = !fifo_full((fifo));                                   \
 195         if (_r) {                                                       \
 196                 --(fifo)->front;                                        \
 197                 (fifo)->front &= (fifo)->mask;                          \
 198                 (fifo)->data[(fifo)->front] = (i);                      \
 199         }                                                               \
 200         _r;                                                             \
 201 })
 202
 203 #define fifo_pop_back(fifo, i)                                          \
 204 ({                                                                      \
 205         bool _r = !fifo_empty((fifo));                                  \
 206         if (_r) {                                                       \
 207                 --(fifo)->back;                                         \
 208                 (fifo)->back &= (fifo)->mask;                           \
 209                 (i) = (fifo)->data[(fifo)->back]                        \
 210         }                                                               \
 211         _r;                                                             \
 212 })
 213
 214 #define fifo_push(fifo, i)      fifo_push_back(fifo, (i))
 215 #define fifo_pop(fifo, i)       fifo_pop_front(fifo, (i))
 216
 217 #define fifo_swap(l, r)                                                 \
 218 do {                                                                    \
 219         swap((l)->front, (r)->front);                                   \
 220         swap((l)->back, (r)->back);                                     \
 221         swap((l)->size, (r)->size);                                     \
 222         swap((l)->mask, (r)->mask);                                     \
 223         swap((l)->data, (r)->data);                                     \
 224 } while (0)
 225
 226 #define fifo_move(dest, src)                                            \
 227 do {                                                                    \
 228         typeof(*((dest)->data)) _t;                                     \
 229         while (!fifo_full(dest) &&                                      \
 230                fifo_pop(src, _t))                                       \
 231                 fifo_push(dest, _t);                                    \
 232 } while (0)
 233
 234 /*
 235  * Simple array based allocator - preallocates a number of elements and you can
 236  * never allocate more than that, also has no locking.
 237  *
 238  * Handy because if you know you only need a fixed number of elements you don't
 239  * have to worry about memory allocation failure, and sometimes a mempool isn't
 240  * what you want.
 241  *
 242  * We treat the free elements as entries in a singly linked list, and the
 243  * freelist as a stack - allocating and freeing push and pop off the freelist.
 244  */
 245
 246 #define DECLARE_ARRAY_ALLOCATOR(type, name, size)                       \
 247         struct {                                                        \
 248                 type    *freelist;                                      \
 249                 type    data[size];                                     \
 250         } name
 251
 252 #define array_alloc(array)                                              \
 253 ({                                                                      \
 254         typeof((array)->freelist) _ret = (array)->freelist;             \
 255                                                                         \
 256         if (_ret)                                                       \
 257                 (array)->freelist = *((typeof((array)->freelist) *) _ret);\
 258                                                                         \
 259         _ret;                                                           \
 260 })
 261
 262 #define array_free(array, ptr)                                          \
 263 do {                                                                    \
 264         typeof((array)->freelist) _ptr = ptr;                           \
 265                                                                         \
 266         *((typeof((array)->freelist) *) _ptr) = (array)->freelist;      \
 267         (array)->freelist = _ptr;                                       \
 268 } while (0)
 269
 270 #define array_allocator_init(array)                                     \
 271 do {                                                                    \
 272         typeof((array)->freelist) _i;                                   \
 273                                                                         \
 274         BUILD_BUG_ON(sizeof((array)->data[0]) < sizeof(void *));        \
 275         (array)->freelist = NULL;                                       \
 276                                                                         \
 277         for (_i = (array)->data;                                        \
 278              _i < (array)->data + ARRAY_SIZE((array)->data);            \
 279              _i++)                                                      \
 280                 array_free(array, _i);                                  \
 281 } while (0)
 282
 283 #define array_freelist_empty(array)     ((array)->freelist == NULL)
 284
 285 #define ANYSINT_MAX(t)                                                  \
 286         ((((t) 1 << (sizeof(t) * 8 - 2)) - (t) 1) * (t) 2 + (t) 1)
 287
 288 int bch_strtoint_h(const char *cp, int *res);
 289 int bch_strtouint_h(const char *cp, unsigned int *res);
 290 int bch_strtoll_h(const char *cp, long long *res);
 291 int bch_strtoull_h(const char *cp, unsigned long long *res);
 292
 293 static inline int bch_strtol_h(const char *cp, long *res)
 294 {
 295 #if BITS_PER_LONG == 32
 296         return bch_strtoint_h(cp, (int *) res);
 297 #else
 298         return bch_strtoll_h(cp, (long long *) res);
 299 #endif
 300 }
 301
 302 static inline int bch_strtoul_h(const char *cp, long *res)
 303 {
 304 #if BITS_PER_LONG == 32
 305         return bch_strtouint_h(cp, (unsigned int *) res);
 306 #else
 307         return bch_strtoull_h(cp, (unsigned long long *) res);
 308 #endif
 309 }
 310
 311 #define strtoi_h(cp, res)                                               \
 312         (__builtin_types_compatible_p(typeof(*res), int)                \
 313         ? bch_strtoint_h(cp, (void *) res)                              \
 314         : __builtin_types_compatible_p(typeof(*res), long)              \
 315         ? bch_strtol_h(cp, (void *) res)                                \
 316         : __builtin_types_compatible_p(typeof(*res), long long)         \
 317         ? bch_strtoll_h(cp, (void *) res)                               \
 318         : __builtin_types_compatible_p(typeof(*res), unsigned int)      \
 319         ? bch_strtouint_h(cp, (void *) res)                             \
 320         : __builtin_types_compatible_p(typeof(*res), unsigned long)     \
 321         ? bch_strtoul_h(cp, (void *) res)                               \
 322         : __builtin_types_compatible_p(typeof(*res), unsigned long long)\
 323         ? bch_strtoull_h(cp, (void *) res) : -EINVAL)
 324
 325 #define strtoul_safe(cp, var)                                           \
 326 ({                                                                      \
 327         unsigned long _v;                                               \
 328         int _r = kstrtoul(cp, 10, &_v);                                 \
 329         if (!_r)                                                        \
 330                 var = _v;                                               \
 331         _r;                                                             \
 332 })
 333
 334 #define strtoul_safe_clamp(cp, var, min, max)                           \
 335 ({                                                                      \
 336         unsigned long _v;                                               \
 337         int _r = kstrtoul(cp, 10, &_v);                                 \
 338         if (!_r)                                                        \
 339                 var = clamp_t(typeof(var), _v, min, max);               \
 340         _r;                                                             \
 341 })
 342
 343 ssize_t bch_hprint(char *buf, int64_t v);
 344
 345 bool bch_is_zero(const char *p, size_t n);
 346 int bch_parse_uuid(const char *s, char *uuid);
 347
 348 struct time_stats {
 349         spinlock_t      lock;
 350         /*
 351          * all fields are in nanoseconds, averages are ewmas stored left shifted
 352          * by 8
 353          */
 354         uint64_t        max_duration;
 355         uint64_t        average_duration;
 356         uint64_t        average_frequency;
 357         uint64_t        last;
 358 };
 359
 360 void bch_time_stats_update(struct time_stats *stats, uint64_t time);
 361
 362 static inline unsigned int local_clock_us(void)
 363 {
 364         return local_clock() >> 10;
 365 }
 366
 367 #define NSEC_PER_ns                     1L
 368 #define NSEC_PER_us                     NSEC_PER_USEC
 369 #define NSEC_PER_ms                     NSEC_PER_MSEC
 370 #define NSEC_PER_sec                    NSEC_PER_SEC
 371
 372 #define __print_time_stat(stats, name, stat, units)                     \
 373         sysfs_print(name ## _ ## stat ## _ ## units,                    \
 374                     div_u64((stats)->stat >> 8, NSEC_PER_ ## units))
 375
 376 #define sysfs_print_time_stats(stats, name,                             \
 377                                frequency_units,                         \
 378                                duration_units)                          \
 379 do {                                                                    \
 380         __print_time_stat(stats, name,                                  \
 381                           average_frequency,    frequency_units);       \
 382         __print_time_stat(stats, name,                                  \
 383                           average_duration,     duration_units);        \
 384         sysfs_print(name ## _ ##max_duration ## _ ## duration_units,    \
 385                         div_u64((stats)->max_duration,                  \
 386                                 NSEC_PER_ ## duration_units));          \
 387                                                                         \
 388         sysfs_print(name ## _last_ ## frequency_units, (stats)->last    \
 389                     ? div_s64(local_clock() - (stats)->last,            \
 390                               NSEC_PER_ ## frequency_units)             \
 391                     : -1LL);                                            \
 392 } while (0)
 393
 394 #define sysfs_time_stats_attribute(name,                                \
 395                                    frequency_units,                     \
 396                                    duration_units)                      \
 397 read_attribute(name ## _average_frequency_ ## frequency_units);         \
 398 read_attribute(name ## _average_duration_ ## duration_units);           \
 399 read_attribute(name ## _max_duration_ ## duration_units);               \
 400 read_attribute(name ## _last_ ## frequency_units)
 401
 402 #define sysfs_time_stats_attribute_list(name,                           \
 403                                         frequency_units,                \
 404                                         duration_units)                 \
 405 &sysfs_ ## name ## _average_frequency_ ## frequency_units,              \
 406 &sysfs_ ## name ## _average_duration_ ## duration_units,                \
 407 &sysfs_ ## name ## _max_duration_ ## duration_units,                    \
 408 &sysfs_ ## name ## _last_ ## frequency_units,
 409
 410 #define ewma_add(ewma, val, weight, factor)                             \
 411 ({                                                                      \
 412         (ewma) *= (weight) - 1;                                         \
 413         (ewma) += (val) << factor;                                      \
 414         (ewma) /= (weight);                                             \
 415         (ewma) >> factor;                                               \
 416 })
 417
 418 struct bch_ratelimit {
 419         /* Next time we want to do some work, in nanoseconds */
 420         uint64_t                next;
 421
 422         /*
 423          * Rate at which we want to do work, in units per second
 424          * The units here correspond to the units passed to bch_next_delay()
 425          */
 426         atomic_long_t           rate;
 427 };
 428
 429 static inline void bch_ratelimit_reset(struct bch_ratelimit *d)
 430 {
 431         d->next = local_clock();
 432 }
 433
 434 uint64_t bch_next_delay(struct bch_ratelimit *d, uint64_t done);
 435
 436 #define __DIV_SAFE(n, d, zero)                                          \
 437 ({                                                                      \
 438         typeof(n) _n = (n);                                             \
 439         typeof(d) _d = (d);                                             \
 440         _d ? _n / _d : zero;                                            \
 441 })
 442
 443 #define DIV_SAFE(n, d)  __DIV_SAFE(n, d, 0)
 444
 445 #define container_of_or_null(ptr, type, member)                         \
 446 ({                                                                      \
 447         typeof(ptr) _ptr = ptr;                                         \
 448         _ptr ? container_of(_ptr, type, member) : NULL;                 \
 449 })
 450
 451 #define RB_INSERT(root, new, member, cmp)                               \
 452 ({                                                                      \
 453         __label__ dup;                                                  \
 454         struct rb_node **n = &(root)->rb_node, *parent = NULL;          \
 455         typeof(new) this;                                               \
 456         int res, ret = -1;                                              \
 457                                                                         \
 458         while (*n) {                                                    \
 459                 parent = *n;                                            \
 460                 this = container_of(*n, typeof(*(new)), member);        \
 461                 res = cmp(new, this);                                   \
 462                 if (!res)                                               \
 463                         goto dup;                                       \
 464                 n = res < 0                                             \
 465                         ? &(*n)->rb_left                                \
 466                         : &(*n)->rb_right;                              \
 467         }                                                               \
 468                                                                         \
 469         rb_link_node(&(new)->member, parent, n);                        \
 470         rb_insert_color(&(new)->member, root);                          \
 471         ret = 0;                                                        \
 472 dup:                                                                    \
 473         ret;                                                            \
 474 })
 475
 476 #define RB_SEARCH(root, search, member, cmp)                            \
 477 ({                                                                      \
 478         struct rb_node *n = (root)->rb_node;                            \
 479         typeof(&(search)) this, ret = NULL;                             \
 480         int res;                                                        \
 481                                                                         \
 482         while (n) {                                                     \
 483                 this = container_of(n, typeof(search), member);         \
 484                 res = cmp(&(search), this);                             \
 485                 if (!res) {                                             \
 486                         ret = this;                                     \
 487                         break;                                          \
 488                 }                                                       \
 489                 n = res < 0                                             \
 490                         ? n->rb_left                                    \
 491                         : n->rb_right;                                  \
 492         }                                                               \
 493         ret;                                                            \
 494 })
 495
 496 #define RB_GREATER(root, search, member, cmp)                           \
 497 ({                                                                      \
 498         struct rb_node *n = (root)->rb_node;                            \
 499         typeof(&(search)) this, ret = NULL;                             \
 500         int res;                                                        \
 501                                                                         \
 502         while (n) {                                                     \
 503                 this = container_of(n, typeof(search), member);         \
 504                 res = cmp(&(search), this);                             \
 505                 if (res < 0) {                                          \
 506                         ret = this;                                     \
 507                         n = n->rb_left;                                 \
 508                 } else                                                  \
 509                         n = n->rb_right;                                \
 510         }                                                               \
 511         ret;                                                            \
 512 })
 513
 514 #define RB_FIRST(root, type, member)                                    \
 515         container_of_or_null(rb_first(root), type, member)
 516
 517 #define RB_LAST(root, type, member)                                     \
 518         container_of_or_null(rb_last(root), type, member)
 519
 520 #define RB_NEXT(ptr, member)                                            \
 521         container_of_or_null(rb_next(&(ptr)->member), typeof(*ptr), member)
 522
 523 #define RB_PREV(ptr, member)                                            \
 524         container_of_or_null(rb_prev(&(ptr)->member), typeof(*ptr), member)
 525
 526 static inline uint64_t bch_crc64(const void *p, size_t len)
 527 {
 528         uint64_t crc = 0xffffffffffffffffULL;
 529
 530         crc = crc64_be(crc, p, len);
 531         return crc ^ 0xffffffffffffffffULL;
 532 }
 533
 534 /*
 535  * A stepwise-linear pseudo-exponential.  This returns 1 << (x >>
 536  * frac_bits), with the less-significant bits filled in by linear
 537  * interpolation.
 538  *
 539  * This can also be interpreted as a floating-point number format,
 540  * where the low frac_bits are the mantissa (with implicit leading
 541  * 1 bit), and the more significant bits are the exponent.
 542  * The return value is 1.mantissa * 2^exponent.
 543  *
 544  * The way this is used, fract_bits is 6 and the largest possible
 545  * input is CONGESTED_MAX-1 = 1023 (exponent 16, mantissa 0x1.fc),
 546  * so the maximum output is 0x1fc00.
 547  */
 548 static inline unsigned int fract_exp_two(unsigned int x,
 549                                          unsigned int fract_bits)
 550 {
 551         unsigned int mantissa = 1 << fract_bits;        /* Implicit bit */
 552
 553         mantissa += x & (mantissa - 1);
 554         x >>= fract_bits;       /* The exponent */
 555         /* Largest intermediate value 0x7f0000 */
 556         return mantissa << x >> fract_bits;
 557 }
 558
 559 void bch_bio_map(struct bio *bio, void *base);
 560 int bch_bio_alloc_pages(struct bio *bio, gfp_t gfp_mask);
 561
 562 #endif /* _BCACHE_UTIL_H */