drivers/md/bcache/util.h

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