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