drivers/md/bcache/util.h

   1
   2 #ifndef _BCACHE_UTIL_H
   3 #define _BCACHE_UTIL_H
   4
   5 #include <linux/errno.h>
   6 #include <linux/kernel.h>
   7 #include <linux/llist.h>
   8 #include <linux/ratelimit.h>
   9 #include <linux/vmalloc.h>
  10 #include <linux/workqueue.h>
  11
  12 #include "closure.h"
  13
  14 #define PAGE_SECTORS            (PAGE_SIZE / 512)
  15
  16 struct closure;
  17
  18 #ifdef CONFIG_BCACHE_EDEBUG
  19
  20 #define atomic_dec_bug(v)       BUG_ON(atomic_dec_return(v) < 0)
  21 #define atomic_inc_bug(v, i)    BUG_ON(atomic_inc_return(v) <= i)
  22
  23 #else /* EDEBUG */
  24
  25 #define atomic_dec_bug(v)       atomic_dec(v)
  26 #define atomic_inc_bug(v, i)    atomic_inc(v)
  27
  28 #endif
  29
  30 #define BITMASK(name, type, field, offset, size)                \
  31 static inline uint64_t name(const type *k)                      \
  32 { return (k->field >> offset) & ~(((uint64_t) ~0) << size); }   \
  33                                                                 \
  34 static inline void SET_##name(type *k, uint64_t v)              \
  35 {                                                               \
  36         k->field &= ~(~((uint64_t) ~0 << size) << offset);      \
  37         k->field |= v << offset;                                \
  38 }
  39
  40 #define DECLARE_HEAP(type, name)                                        \
  41         struct {                                                        \
  42                 size_t size, used;                                      \
  43                 type *data;                                             \
  44         } name
  45
  46 #define init_heap(heap, _size, gfp)                                     \
  47 ({                                                                      \
  48         size_t _bytes;                                                  \
  49         (heap)->used = 0;                                               \
  50         (heap)->size = (_size);                                         \
  51         _bytes = (heap)->size * sizeof(*(heap)->data);                  \
  52         (heap)->data = NULL;                                            \
  53         if (_bytes < KMALLOC_MAX_SIZE)                                  \
  54                 (heap)->data = kmalloc(_bytes, (gfp));                  \
  55         if ((!(heap)->data) && ((gfp) & GFP_KERNEL))                    \
  56                 (heap)->data = vmalloc(_bytes);                         \
  57         (heap)->data;                                                   \
  58 })
  59
  60 #define free_heap(heap)                                                 \
  61 do {                                                                    \
  62         if (is_vmalloc_addr((heap)->data))                              \
  63                 vfree((heap)->data);                                    \
  64         else                                                            \
  65                 kfree((heap)->data);                                    \
  66         (heap)->data = NULL;                                            \
  67 } while (0)
  68
  69 #define heap_swap(h, i, j)      swap((h)->data[i], (h)->data[j])
  70
  71 #define heap_sift(h, i, cmp)                                            \
  72 do {                                                                    \
  73         size_t _r, _j = i;                                              \
  74                                                                         \
  75         for (; _j * 2 + 1 < (h)->used; _j = _r) {                       \
  76                 _r = _j * 2 + 1;                                        \
  77                 if (_r + 1 < (h)->used &&                               \
  78                     cmp((h)->data[_r], (h)->data[_r + 1]))              \
  79                         _r++;                                           \
  80                                                                         \
  81                 if (cmp((h)->data[_r], (h)->data[_j]))                  \
  82                         break;                                          \
  83                 heap_swap(h, _r, _j);                                   \
  84         }                                                               \
  85 } while (0)
  86
  87 #define heap_sift_down(h, i, cmp)                                       \
  88 do {                                                                    \
  89         while (i) {                                                     \
  90                 size_t p = (i - 1) / 2;                                 \
  91                 if (cmp((h)->data[i], (h)->data[p]))                    \
  92                         break;                                          \
  93                 heap_swap(h, i, p);                                     \
  94                 i = p;                                                  \
  95         }                                                               \
  96 } while (0)
  97
  98 #define heap_add(h, d, cmp)                                             \
  99 ({                                                                      \
 100         bool _r = !heap_full(h);                                        \
 101         if (_r) {                                                       \
 102                 size_t _i = (h)->used++;                                \
 103                 (h)->data[_i] = d;                                      \
 104                                                                         \
 105                 heap_sift_down(h, _i, cmp);                             \
 106                 heap_sift(h, _i, cmp);                                  \
 107         }                                                               \
 108         _r;                                                             \
 109 })
 110
 111 #define heap_pop(h, d, cmp)                                             \
 112 ({                                                                      \
 113         bool _r = (h)->used;                                            \
 114         if (_r) {                                                       \
 115                 (d) = (h)->data[0];                                     \
 116                 (h)->used--;                                            \
 117                 heap_swap(h, 0, (h)->used);                             \
 118                 heap_sift(h, 0, cmp);                                   \
 119         }                                                               \
 120         _r;                                                             \
 121 })
 122
 123 #define heap_peek(h)    ((h)->size ? (h)->data[0] : NULL)
 124
 125 #define heap_full(h)    ((h)->used == (h)->size)
 126
 127 #define DECLARE_FIFO(type, name)                                        \
 128         struct {                                                        \
 129                 size_t front, back, size, mask;                         \
 130                 type *data;                                             \
 131         } name
 132
 133 #define fifo_for_each(c, fifo, iter)                                    \
 134         for (iter = (fifo)->front;                                      \
 135              c = (fifo)->data[iter], iter != (fifo)->back;              \
 136              iter = (iter + 1) & (fifo)->mask)
 137
 138 #define __init_fifo(fifo, gfp)                                          \
 139 ({                                                                      \
 140         size_t _allocated_size, _bytes;                                 \
 141         BUG_ON(!(fifo)->size);                                          \
 142                                                                         \
 143         _allocated_size = roundup_pow_of_two((fifo)->size + 1);         \
 144         _bytes = _allocated_size * sizeof(*(fifo)->data);               \
 145                                                                         \
 146         (fifo)->mask = _allocated_size - 1;                             \
 147         (fifo)->front = (fifo)->back = 0;                               \
 148         (fifo)->data = NULL;                                            \
 149                                                                         \
 150         if (_bytes < KMALLOC_MAX_SIZE)                                  \
 151                 (fifo)->data = kmalloc(_bytes, (gfp));                  \
 152         if ((!(fifo)->data) && ((gfp) & GFP_KERNEL))                    \
 153                 (fifo)->data = vmalloc(_bytes);                         \
 154         (fifo)->data;                                                   \
 155 })
 156
 157 #define init_fifo_exact(fifo, _size, gfp)                               \
 158 ({                                                                      \
 159         (fifo)->size = (_size);                                         \
 160         __init_fifo(fifo, gfp);                                         \
 161 })
 162
 163 #define init_fifo(fifo, _size, gfp)                                     \
 164 ({                                                                      \
 165         (fifo)->size = (_size);                                         \
 166         if ((fifo)->size > 4)                                           \
 167                 (fifo)->size = roundup_pow_of_two((fifo)->size) - 1;    \
 168         __init_fifo(fifo, gfp);                                         \
 169 })
 170
 171 #define free_fifo(fifo)                                                 \
 172 do {                                                                    \
 173         if (is_vmalloc_addr((fifo)->data))                              \
 174                 vfree((fifo)->data);                                    \
 175         else                                                            \
 176                 kfree((fifo)->data);                                    \
 177         (fifo)->data = NULL;                                            \
 178 } while (0)
 179
 180 #define fifo_used(fifo)         (((fifo)->back - (fifo)->front) & (fifo)->mask)
 181 #define fifo_free(fifo)         ((fifo)->size - fifo_used(fifo))
 182
 183 #define fifo_empty(fifo)        (!fifo_used(fifo))
 184 #define fifo_full(fifo)         (!fifo_free(fifo))
 185
 186 #define fifo_front(fifo)        ((fifo)->data[(fifo)->front])
 187 #define fifo_back(fifo)                                                 \
 188         ((fifo)->data[((fifo)->back - 1) & (fifo)->mask])
 189
 190 #define fifo_idx(fifo, p)       (((p) - &fifo_front(fifo)) & (fifo)->mask)
 191
 192 #define fifo_push_back(fifo, i)                                         \
 193 ({                                                                      \
 194         bool _r = !fifo_full((fifo));                                   \
 195         if (_r) {                                                       \
 196                 (fifo)->data[(fifo)->back++] = (i);                     \
 197                 (fifo)->back &= (fifo)->mask;                           \
 198         }                                                               \
 199         _r;                                                             \
 200 })
 201
 202 #define fifo_pop_front(fifo, i)                                         \
 203 ({                                                                      \
 204         bool _r = !fifo_empty((fifo));                                  \
 205         if (_r) {                                                       \
 206                 (i) = (fifo)->data[(fifo)->front++];                    \
 207                 (fifo)->front &= (fifo)->mask;                          \
 208         }                                                               \
 209         _r;                                                             \
 210 })
 211
 212 #define fifo_push_front(fifo, i)                                        \
 213 ({                                                                      \
 214         bool _r = !fifo_full((fifo));                                   \
 215         if (_r) {                                                       \
 216                 --(fifo)->front;                                        \
 217                 (fifo)->front &= (fifo)->mask;                          \
 218                 (fifo)->data[(fifo)->front] = (i);                      \
 219         }                                                               \
 220         _r;                                                             \
 221 })
 222
 223 #define fifo_pop_back(fifo, i)                                          \
 224 ({                                                                      \
 225         bool _r = !fifo_empty((fifo));                                  \
 226         if (_r) {                                                       \
 227                 --(fifo)->back;                                         \
 228                 (fifo)->back &= (fifo)->mask;                           \
 229                 (i) = (fifo)->data[(fifo)->back]                        \
 230         }                                                               \
 231         _r;                                                             \
 232 })
 233
 234 #define fifo_push(fifo, i)      fifo_push_back(fifo, (i))
 235 #define fifo_pop(fifo, i)       fifo_pop_front(fifo, (i))
 236
 237 #define fifo_swap(l, r)                                                 \
 238 do {                                                                    \
 239         swap((l)->front, (r)->front);                                   \
 240         swap((l)->back, (r)->back);                                     \
 241         swap((l)->size, (r)->size);                                     \
 242         swap((l)->mask, (r)->mask);                                     \
 243         swap((l)->data, (r)->data);                                     \
 244 } while (0)
 245
 246 #define fifo_move(dest, src)                                            \
 247 do {                                                                    \
 248         typeof(*((dest)->data)) _t;                                     \
 249         while (!fifo_full(dest) &&                                      \
 250                fifo_pop(src, _t))                                       \
 251                 fifo_push(dest, _t);                                    \
 252 } while (0)
 253
 254 /*
 255  * Simple array based allocator - preallocates a number of elements and you can
 256  * never allocate more than that, also has no locking.
 257  *
 258  * Handy because if you know you only need a fixed number of elements you don't
 259  * have to worry about memory allocation failure, and sometimes a mempool isn't
 260  * what you want.
 261  *
 262  * We treat the free elements as entries in a singly linked list, and the
 263  * freelist as a stack - allocating and freeing push and pop off the freelist.
 264  */
 265
 266 #define DECLARE_ARRAY_ALLOCATOR(type, name, size)                       \
 267         struct {                                                        \
 268                 type    *freelist;                                      \
 269                 type    data[size];                                     \
 270         } name
 271
 272 #define array_alloc(array)                                              \
 273 ({                                                                      \
 274         typeof((array)->freelist) _ret = (array)->freelist;             \
 275                                                                         \
 276         if (_ret)                                                       \
 277                 (array)->freelist = *((typeof((array)->freelist) *) _ret);\
 278                                                                         \
 279         _ret;                                                           \
 280 })
 281
 282 #define array_free(array, ptr)                                          \
 283 do {                                                                    \
 284         typeof((array)->freelist) _ptr = ptr;                           \
 285                                                                         \
 286         *((typeof((array)->freelist) *) _ptr) = (array)->freelist;      \
 287         (array)->freelist = _ptr;                                       \
 288 } while (0)
 289
 290 #define array_allocator_init(array)                                     \
 291 do {                                                                    \
 292         typeof((array)->freelist) _i;                                   \
 293                                                                         \
 294         BUILD_BUG_ON(sizeof((array)->data[0]) < sizeof(void *));        \
 295         (array)->freelist = NULL;                                       \
 296                                                                         \
 297         for (_i = (array)->data;                                        \
 298              _i < (array)->data + ARRAY_SIZE((array)->data);            \
 299              _i++)                                                      \
 300                 array_free(array, _i);                                  \
 301 } while (0)
 302
 303 #define array_freelist_empty(array)     ((array)->freelist == NULL)
 304
 305 #define ANYSINT_MAX(t)                                                  \
 306         ((((t) 1 << (sizeof(t) * 8 - 2)) - (t) 1) * (t) 2 + (t) 1)
 307
 308 int bch_strtoint_h(const char *, int *);
 309 int bch_strtouint_h(const char *, unsigned int *);
 310 int bch_strtoll_h(const char *, long long *);
 311 int bch_strtoull_h(const char *, unsigned long long *);
 312
 313 static inline int bch_strtol_h(const char *cp, long *res)
 314 {
 315 #if BITS_PER_LONG == 32
 316         return bch_strtoint_h(cp, (int *) res);
 317 #else
 318         return bch_strtoll_h(cp, (long long *) res);
 319 #endif
 320 }
 321
 322 static inline int bch_strtoul_h(const char *cp, long *res)
 323 {
 324 #if BITS_PER_LONG == 32
 325         return bch_strtouint_h(cp, (unsigned int *) res);
 326 #else
 327         return bch_strtoull_h(cp, (unsigned long long *) res);
 328 #endif
 329 }
 330
 331 #define strtoi_h(cp, res)                                               \
 332         (__builtin_types_compatible_p(typeof(*res), int)                \
 333         ? bch_strtoint_h(cp, (void *) res)                              \
 334         : __builtin_types_compatible_p(typeof(*res), long)              \
 335         ? bch_strtol_h(cp, (void *) res)                                \
 336         : __builtin_types_compatible_p(typeof(*res), long long)         \
 337         ? bch_strtoll_h(cp, (void *) res)                               \
 338         : __builtin_types_compatible_p(typeof(*res), unsigned int)      \
 339         ? bch_strtouint_h(cp, (void *) res)                             \
 340         : __builtin_types_compatible_p(typeof(*res), unsigned long)     \
 341         ? bch_strtoul_h(cp, (void *) res)                               \
 342         : __builtin_types_compatible_p(typeof(*res), unsigned long long)\
 343         ? bch_strtoull_h(cp, (void *) res) : -EINVAL)
 344
 345 #define strtoul_safe(cp, var)                                           \
 346 ({                                                                      \
 347         unsigned long _v;                                               \
 348         int _r = kstrtoul(cp, 10, &_v);                                 \
 349         if (!_r)                                                        \
 350                 var = _v;                                               \
 351         _r;                                                             \
 352 })
 353
 354 #define strtoul_safe_clamp(cp, var, min, max)                           \
 355 ({                                                                      \
 356         unsigned long _v;                                               \
 357         int _r = kstrtoul(cp, 10, &_v);                                 \
 358         if (!_r)                                                        \
 359                 var = clamp_t(typeof(var), _v, min, max);               \
 360         _r;                                                             \
 361 })
 362
 363 #define snprint(buf, size, var)                                         \
 364         snprintf(buf, size,                                             \
 365                 __builtin_types_compatible_p(typeof(var), int)          \
 366                      ? "%i\n" :                                         \
 367                 __builtin_types_compatible_p(typeof(var), unsigned)     \
 368                      ? "%u\n" :                                         \
 369                 __builtin_types_compatible_p(typeof(var), long)         \
 370                      ? "%li\n" :                                        \
 371                 __builtin_types_compatible_p(typeof(var), unsigned long)\
 372                      ? "%lu\n" :                                        \
 373                 __builtin_types_compatible_p(typeof(var), int64_t)      \
 374                      ? "%lli\n" :                                       \
 375                 __builtin_types_compatible_p(typeof(var), uint64_t)     \
 376                      ? "%llu\n" :                                       \
 377                 __builtin_types_compatible_p(typeof(var), const char *) \
 378                      ? "%s\n" : "%i\n", var)
 379
 380 ssize_t bch_hprint(char *buf, int64_t v);
 381
 382 bool bch_is_zero(const char *p, size_t n);
 383 int bch_parse_uuid(const char *s, char *uuid);
 384
 385 ssize_t bch_snprint_string_list(char *buf, size_t size, const char * const list[],
 386                             size_t selected);
 387
 388 ssize_t bch_read_string_list(const char *buf, const char * const list[]);
 389
 390 struct time_stats {
 391         /*
 392          * all fields are in nanoseconds, averages are ewmas stored left shifted
 393          * by 8
 394          */
 395         uint64_t        max_duration;
 396         uint64_t        average_duration;
 397         uint64_t        average_frequency;
 398         uint64_t        last;
 399 };
 400
 401 void bch_time_stats_update(struct time_stats *stats, uint64_t time);
 402
 403 #define NSEC_PER_ns                     1L
 404 #define NSEC_PER_us                     NSEC_PER_USEC
 405 #define NSEC_PER_ms                     NSEC_PER_MSEC
 406 #define NSEC_PER_sec                    NSEC_PER_SEC
 407
 408 #define __print_time_stat(stats, name, stat, units)                     \
 409         sysfs_print(name ## _ ## stat ## _ ## units,                    \
 410                     div_u64((stats)->stat >> 8, NSEC_PER_ ## units))
 411
 412 #define sysfs_print_time_stats(stats, name,                             \
 413                                frequency_units,                         \
 414                                duration_units)                          \
 415 do {                                                                    \
 416         __print_time_stat(stats, name,                                  \
 417                           average_frequency,    frequency_units);       \
 418         __print_time_stat(stats, name,                                  \
 419                           average_duration,     duration_units);        \
 420         __print_time_stat(stats, name,                                  \
 421                           max_duration,         duration_units);        \
 422                                                                         \
 423         sysfs_print(name ## _last_ ## frequency_units, (stats)->last    \
 424                     ? div_s64(local_clock() - (stats)->last,            \
 425                               NSEC_PER_ ## frequency_units)             \
 426                     : -1LL);                                            \
 427 } while (0)
 428
 429 #define sysfs_time_stats_attribute(name,                                \
 430                                    frequency_units,                     \
 431                                    duration_units)                      \
 432 read_attribute(name ## _average_frequency_ ## frequency_units);         \
 433 read_attribute(name ## _average_duration_ ## duration_units);           \
 434 read_attribute(name ## _max_duration_ ## duration_units);               \
 435 read_attribute(name ## _last_ ## frequency_units)
 436
 437 #define sysfs_time_stats_attribute_list(name,                           \
 438                                         frequency_units,                \
 439                                         duration_units)                 \
 440 &sysfs_ ## name ## _average_frequency_ ## frequency_units,              \
 441 &sysfs_ ## name ## _average_duration_ ## duration_units,                \
 442 &sysfs_ ## name ## _max_duration_ ## duration_units,                    \
 443 &sysfs_ ## name ## _last_ ## frequency_units,
 444
 445 #define ewma_add(ewma, val, weight, factor)                             \
 446 ({                                                                      \
 447         (ewma) *= (weight) - 1;                                         \
 448         (ewma) += (val) << factor;                                      \
 449         (ewma) /= (weight);                                             \
 450         (ewma) >> factor;                                               \
 451 })
 452
 453 struct bch_ratelimit {
 454         /* Next time we want to do some work, in nanoseconds */
 455         uint64_t                next;
 456
 457         /*
 458          * Rate at which we want to do work, in units per nanosecond
 459          * The units here correspond to the units passed to bch_next_delay()
 460          */
 461         unsigned                rate;
 462 };
 463
 464 static inline void bch_ratelimit_reset(struct bch_ratelimit *d)
 465 {
 466         d->next = local_clock();
 467 }
 468
 469 uint64_t bch_next_delay(struct bch_ratelimit *d, uint64_t done);
 470
 471 #define __DIV_SAFE(n, d, zero)                                          \
 472 ({                                                                      \
 473         typeof(n) _n = (n);                                             \
 474         typeof(d) _d = (d);                                             \
 475         _d ? _n / _d : zero;                                            \
 476 })
 477
 478 #define DIV_SAFE(n, d)  __DIV_SAFE(n, d, 0)
 479
 480 #define container_of_or_null(ptr, type, member)                         \
 481 ({                                                                      \
 482         typeof(ptr) _ptr = ptr;                                         \
 483         _ptr ? container_of(_ptr, type, member) : NULL;                 \
 484 })
 485
 486 #define RB_INSERT(root, new, member, cmp)                               \
 487 ({                                                                      \
 488         __label__ dup;                                                  \
 489         struct rb_node **n = &(root)->rb_node, *parent = NULL;          \
 490         typeof(new) this;                                               \
 491         int res, ret = -1;                                              \
 492                                                                         \
 493         while (*n) {                                                    \
 494                 parent = *n;                                            \
 495                 this = container_of(*n, typeof(*(new)), member);        \
 496                 res = cmp(new, this);                                   \
 497                 if (!res)                                               \
 498                         goto dup;                                       \
 499                 n = res < 0                                             \
 500                         ? &(*n)->rb_left                                \
 501                         : &(*n)->rb_right;                              \
 502         }                                                               \
 503                                                                         \
 504         rb_link_node(&(new)->member, parent, n);                        \
 505         rb_insert_color(&(new)->member, root);                          \
 506         ret = 0;                                                        \
 507 dup:                                                                    \
 508         ret;                                                            \
 509 })
 510
 511 #define RB_SEARCH(root, search, member, cmp)                            \
 512 ({                                                                      \
 513         struct rb_node *n = (root)->rb_node;                            \
 514         typeof(&(search)) this, ret = NULL;                             \
 515         int res;                                                        \
 516                                                                         \
 517         while (n) {                                                     \
 518                 this = container_of(n, typeof(search), member);         \
 519                 res = cmp(&(search), this);                             \
 520                 if (!res) {                                             \
 521                         ret = this;                                     \
 522                         break;                                          \
 523                 }                                                       \
 524                 n = res < 0                                             \
 525                         ? n->rb_left                                    \
 526                         : n->rb_right;                                  \
 527         }                                                               \
 528         ret;                                                            \
 529 })
 530
 531 #define RB_GREATER(root, search, member, cmp)                           \
 532 ({                                                                      \
 533         struct rb_node *n = (root)->rb_node;                            \
 534         typeof(&(search)) this, ret = NULL;                             \
 535         int res;                                                        \
 536                                                                         \
 537         while (n) {                                                     \
 538                 this = container_of(n, typeof(search), member);         \
 539                 res = cmp(&(search), this);                             \
 540                 if (res < 0) {                                          \
 541                         ret = this;                                     \
 542                         n = n->rb_left;                                 \
 543                 } else                                                  \
 544                         n = n->rb_right;                                \
 545         }                                                               \
 546         ret;                                                            \
 547 })
 548
 549 #define RB_FIRST(root, type, member)                                    \
 550         container_of_or_null(rb_first(root), type, member)
 551
 552 #define RB_LAST(root, type, member)                                     \
 553         container_of_or_null(rb_last(root), type, member)
 554
 555 #define RB_NEXT(ptr, member)                                            \
 556         container_of_or_null(rb_next(&(ptr)->member), typeof(*ptr), member)
 557
 558 #define RB_PREV(ptr, member)                                            \
 559         container_of_or_null(rb_prev(&(ptr)->member), typeof(*ptr), member)
 560
 561 /* Does linear interpolation between powers of two */
 562 static inline unsigned fract_exp_two(unsigned x, unsigned fract_bits)
 563 {
 564         unsigned fract = x & ~(~0 << fract_bits);
 565
 566         x >>= fract_bits;
 567         x   = 1 << x;
 568         x  += (x * fract) >> fract_bits;
 569
 570         return x;
 571 }
 572
 573 void bch_bio_map(struct bio *bio, void *base);
 574
 575 static inline sector_t bdev_sectors(struct block_device *bdev)
 576 {
 577         return bdev->bd_inode->i_size >> 9;
 578 }
 579
 580 #define closure_bio_submit(bio, cl, dev)                                \
 581 do {                                                                    \
 582         closure_get(cl);                                                \
 583         bch_generic_make_request(bio, &(dev)->bio_split_hook);          \
 584 } while (0)
 585
 586 uint64_t bch_crc64_update(uint64_t, const void *, size_t);
 587 uint64_t bch_crc64(const void *, size_t);
 588
 589 #endif /* _BCACHE_UTIL_H */