git.sesse.net Git - bcachefs-tools-debian/blob - libbcachefs/util.h

   1 #ifndef _BCACHE_UTIL_H
   2 #define _BCACHE_UTIL_H
   3
   4 #include <linux/bio.h>
   5 #include <linux/blkdev.h>
   6 #include <linux/closure.h>
   7 #include <linux/errno.h>
   8 #include <linux/blkdev.h>
   9 #include <linux/freezer.h>
  10 #include <linux/kernel.h>
  11 #include <linux/llist.h>
  12 #include <linux/log2.h>
  13 #include <linux/ratelimit.h>
  14 #include <linux/slab.h>
  15 #include <linux/vmalloc.h>
  16 #include <linux/workqueue.h>
  17
  18 #define PAGE_SECTOR_SHIFT       (PAGE_SHIFT - 9)
  19 #define PAGE_SECTORS            (1UL << PAGE_SECTOR_SHIFT)
  20
  21 struct closure;
  22
  23 #ifdef CONFIG_BCACHEFS_DEBUG
  24
  25 #define EBUG_ON(cond)           BUG_ON(cond)
  26 #define atomic_dec_bug(v)       BUG_ON(atomic_dec_return(v) < 0)
  27 #define atomic_inc_bug(v, i)    BUG_ON(atomic_inc_return(v) <= i)
  28 #define atomic_sub_bug(i, v)    BUG_ON(atomic_sub_return(i, v) < 0)
  29 #define atomic_add_bug(i, v)    BUG_ON(atomic_add_return(i, v) < 0)
  30 #define atomic_long_dec_bug(v)          BUG_ON(atomic_long_dec_return(v) < 0)
  31 #define atomic_long_sub_bug(i, v)       BUG_ON(atomic_long_sub_return(i, v) < 0)
  32 #define atomic64_dec_bug(v)     BUG_ON(atomic64_dec_return(v) < 0)
  33 #define atomic64_inc_bug(v, i)  BUG_ON(atomic64_inc_return(v) <= i)
  34 #define atomic64_sub_bug(i, v)  BUG_ON(atomic64_sub_return(i, v) < 0)
  35 #define atomic64_add_bug(i, v)  BUG_ON(atomic64_add_return(i, v) < 0)
  36
  37 #define memcpy(_dst, _src, _len)                                        \
  38 do {                                                                    \
  39         BUG_ON(!((void *) (_dst) >= (void *) (_src) + (_len) ||         \
  40                  (void *) (_dst) + (_len) <= (void *) (_src)));         \
  41         memcpy(_dst, _src, _len);                                       \
  42 } while (0)
  43
  44 #else /* DEBUG */
  45
  46 #define EBUG_ON(cond)
  47 #define atomic_dec_bug(v)       atomic_dec(v)
  48 #define atomic_inc_bug(v, i)    atomic_inc(v)
  49 #define atomic_sub_bug(i, v)    atomic_sub(i, v)
  50 #define atomic_add_bug(i, v)    atomic_add(i, v)
  51 #define atomic_long_dec_bug(v)          atomic_long_dec(v)
  52 #define atomic_long_sub_bug(i, v)       atomic_long_sub(i, v)
  53 #define atomic64_dec_bug(v)     atomic64_dec(v)
  54 #define atomic64_inc_bug(v, i)  atomic64_inc(v)
  55 #define atomic64_sub_bug(i, v)  atomic64_sub(i, v)
  56 #define atomic64_add_bug(i, v)  atomic64_add(i, v)
  57
  58 #endif
  59
  60 #ifndef __CHECKER__
  61 #define __flatten __attribute__((flatten))
  62 #else
  63 /* sparse doesn't know about attribute((flatten)) */
  64 #define __flatten
  65 #endif
  66
  67 #ifdef __LITTLE_ENDIAN
  68 #define CPU_BIG_ENDIAN          0
  69 #else
  70 #define CPU_BIG_ENDIAN          1
  71 #endif
  72
  73 /* type hackery */
  74
  75 #define type_is_exact(_val, _type)                                      \
  76         __builtin_types_compatible_p(typeof(_val), _type)
  77
  78 #define type_is(_val, _type)                                            \
  79         (__builtin_types_compatible_p(typeof(_val), _type) ||           \
  80          __builtin_types_compatible_p(typeof(_val), const _type))
  81
  82 static inline void kvpfree(void *p, size_t size)
  83 {
  84         if (size < PAGE_SIZE)
  85                 kfree(p);
  86         else if (is_vmalloc_addr(p))
  87                 vfree(p);
  88         else
  89                 free_pages((unsigned long) p, get_order(size));
  90
  91 }
  92
  93 static inline void *kvpmalloc(size_t size, gfp_t gfp_mask)
  94 {
  95         return size < PAGE_SIZE ? kmalloc(size, gfp_mask)
  96                 :  (void *) __get_free_pages(gfp_mask, get_order(size))
  97                 ?: __vmalloc(size, gfp_mask, PAGE_KERNEL);
  98 }
  99
 100 #define DECLARE_HEAP(type, name)                                        \
 101         struct {                                                        \
 102                 size_t size, used;                                      \
 103                 type *data;                                             \
 104         } name
 105
 106 #define init_heap(heap, _size, gfp)                                     \
 107 ({                                                                      \
 108         (heap)->used = 0;                                               \
 109         (heap)->size = (_size);                                         \
 110         (heap)->data = kvpmalloc((heap)->size * sizeof((heap)->data[0]),\
 111                                  (gfp));                                \
 112 })
 113
 114 #define free_heap(heap)                                                 \
 115 do {                                                                    \
 116         kvpfree((heap)->data, (heap)->size * sizeof((heap)->data[0]));  \
 117         (heap)->data = NULL;                                            \
 118 } while (0)
 119
 120 #define heap_swap(h, i, j)      swap((h)->data[i], (h)->data[j])
 121
 122 #define heap_sift(h, i, cmp)                                            \
 123 do {                                                                    \
 124         size_t _r, _j = i;                                              \
 125                                                                         \
 126         for (; _j * 2 + 1 < (h)->used; _j = _r) {                       \
 127                 _r = _j * 2 + 1;                                        \
 128                 if (_r + 1 < (h)->used &&                               \
 129                     cmp((h)->data[_r], (h)->data[_r + 1]))              \
 130                         _r++;                                           \
 131                                                                         \
 132                 if (cmp((h)->data[_r], (h)->data[_j]))                  \
 133                         break;                                          \
 134                 heap_swap(h, _r, _j);                                   \
 135         }                                                               \
 136 } while (0)
 137
 138 #define heap_sift_down(h, i, cmp)                                       \
 139 do {                                                                    \
 140         while (i) {                                                     \
 141                 size_t p = (i - 1) / 2;                                 \
 142                 if (cmp((h)->data[i], (h)->data[p]))                    \
 143                         break;                                          \
 144                 heap_swap(h, i, p);                                     \
 145                 i = p;                                                  \
 146         }                                                               \
 147 } while (0)
 148
 149 #define heap_add(h, d, cmp)                                             \
 150 ({                                                                      \
 151         bool _r = !heap_full(h);                                        \
 152         if (_r) {                                                       \
 153                 size_t _i = (h)->used++;                                \
 154                 (h)->data[_i] = d;                                      \
 155                                                                         \
 156                 heap_sift_down(h, _i, cmp);                             \
 157                 heap_sift(h, _i, cmp);                                  \
 158         }                                                               \
 159         _r;                                                             \
 160 })
 161
 162 #define heap_del(h, i, cmp)                                             \
 163 do {                                                                    \
 164         size_t _i = (i);                                                \
 165                                                                         \
 166         BUG_ON(_i >= (h)->used);                                        \
 167         (h)->used--;                                                    \
 168         heap_swap(h, _i, (h)->used);                                    \
 169         heap_sift_down(h, _i, cmp);                                     \
 170         heap_sift(h, _i, cmp);                                          \
 171 } while (0)
 172
 173 #define heap_pop(h, d, cmp)                                             \
 174 ({                                                                      \
 175         bool _r = (h)->used;                                            \
 176         if (_r) {                                                       \
 177                 (d) = (h)->data[0];                                     \
 178                 heap_del(h, 0, cmp);                                    \
 179         }                                                               \
 180         _r;                                                             \
 181 })
 182
 183 #define heap_peek(h)                                                    \
 184 ({                                                                      \
 185         EBUG_ON(!(h)->used);                                            \
 186         (h)->data[0];                                                   \
 187 })
 188
 189 #define heap_full(h)    ((h)->used == (h)->size)
 190
 191 #define heap_resort(heap, cmp)                                          \
 192 do {                                                                    \
 193         ssize_t _i;                                                     \
 194         for (_i = (ssize_t) (heap)->used / 2 -  1; _i >= 0; --_i)       \
 195                 heap_sift(heap, _i, cmp);                               \
 196 } while (0)
 197
 198 /*
 199  * Simple array based allocator - preallocates a number of elements and you can
 200  * never allocate more than that, also has no locking.
 201  *
 202  * Handy because if you know you only need a fixed number of elements you don't
 203  * have to worry about memory allocation failure, and sometimes a mempool isn't
 204  * what you want.
 205  *
 206  * We treat the free elements as entries in a singly linked list, and the
 207  * freelist as a stack - allocating and freeing push and pop off the freelist.
 208  */
 209
 210 #define DECLARE_ARRAY_ALLOCATOR(type, name, size)                       \
 211         struct {                                                        \
 212                 type    *freelist;                                      \
 213                 type    data[size];                                     \
 214         } name
 215
 216 #define array_alloc(array)                                              \
 217 ({                                                                      \
 218         typeof((array)->freelist) _ret = (array)->freelist;             \
 219                                                                         \
 220         if (_ret)                                                       \
 221                 (array)->freelist = *((typeof((array)->freelist) *) _ret);\
 222                                                                         \
 223         _ret;                                                           \
 224 })
 225
 226 #define array_free(array, ptr)                                          \
 227 do {                                                                    \
 228         typeof((array)->freelist) _ptr = ptr;                           \
 229                                                                         \
 230         *((typeof((array)->freelist) *) _ptr) = (array)->freelist;      \
 231         (array)->freelist = _ptr;                                       \
 232 } while (0)
 233
 234 #define array_allocator_init(array)                                     \
 235 do {                                                                    \
 236         typeof((array)->freelist) _i;                                   \
 237                                                                         \
 238         BUILD_BUG_ON(sizeof((array)->data[0]) < sizeof(void *));        \
 239         (array)->freelist = NULL;                                       \
 240                                                                         \
 241         for (_i = (array)->data;                                        \
 242              _i < (array)->data + ARRAY_SIZE((array)->data);            \
 243              _i++)                                                      \
 244                 array_free(array, _i);                                  \
 245 } while (0)
 246
 247 #define array_freelist_empty(array)     ((array)->freelist == NULL)
 248
 249 #define ANYSINT_MAX(t)                                                  \
 250         ((((t) 1 << (sizeof(t) * 8 - 2)) - (t) 1) * (t) 2 + (t) 1)
 251
 252 int bch2_strtoint_h(const char *, int *);
 253 int bch2_strtouint_h(const char *, unsigned int *);
 254 int bch2_strtoll_h(const char *, long long *);
 255 int bch2_strtoull_h(const char *, unsigned long long *);
 256
 257 static inline int bch2_strtol_h(const char *cp, long *res)
 258 {
 259 #if BITS_PER_LONG == 32
 260         return bch2_strtoint_h(cp, (int *) res);
 261 #else
 262         return bch2_strtoll_h(cp, (long long *) res);
 263 #endif
 264 }
 265
 266 static inline int bch2_strtoul_h(const char *cp, long *res)
 267 {
 268 #if BITS_PER_LONG == 32
 269         return bch2_strtouint_h(cp, (unsigned int *) res);
 270 #else
 271         return bch2_strtoull_h(cp, (unsigned long long *) res);
 272 #endif
 273 }
 274
 275 #define strtoi_h(cp, res)                                               \
 276         ( type_is(*res, int)            ? bch2_strtoint_h(cp, (void *) res)\
 277         : type_is(*res, long)           ? bch2_strtol_h(cp, (void *) res)\
 278         : type_is(*res, long long)      ? bch2_strtoll_h(cp, (void *) res)\
 279         : type_is(*res, unsigned)       ? bch2_strtouint_h(cp, (void *) res)\
 280         : type_is(*res, unsigned long)  ? bch2_strtoul_h(cp, (void *) res)\
 281         : type_is(*res, unsigned long long) ? bch2_strtoull_h(cp, (void *) res)\
 282         : -EINVAL)
 283
 284 #define strtoul_safe(cp, var)                                           \
 285 ({                                                                      \
 286         unsigned long _v;                                               \
 287         int _r = kstrtoul(cp, 10, &_v);                                 \
 288         if (!_r)                                                        \
 289                 var = _v;                                               \
 290         _r;                                                             \
 291 })
 292
 293 #define strtoul_safe_clamp(cp, var, min, max)                           \
 294 ({                                                                      \
 295         unsigned long _v;                                               \
 296         int _r = kstrtoul(cp, 10, &_v);                                 \
 297         if (!_r)                                                        \
 298                 var = clamp_t(typeof(var), _v, min, max);               \
 299         _r;                                                             \
 300 })
 301
 302 #define strtoul_safe_restrict(cp, var, min, max)                        \
 303 ({                                                                      \
 304         unsigned long _v;                                               \
 305         int _r = kstrtoul(cp, 10, &_v);                                 \
 306         if (!_r && _v >= min && _v <= max)                              \
 307                 var = _v;                                               \
 308         else                                                            \
 309                 _r = -EINVAL;                                           \
 310         _r;                                                             \
 311 })
 312
 313 #define snprint(buf, size, var)                                         \
 314         snprintf(buf, size,                                             \
 315                    type_is(var, int)            ? "%i\n"                \
 316                  : type_is(var, unsigned)       ? "%u\n"                \
 317                  : type_is(var, long)           ? "%li\n"               \
 318                  : type_is(var, unsigned long)  ? "%lu\n"               \
 319                  : type_is(var, s64)            ? "%lli\n"              \
 320                  : type_is(var, u64)            ? "%llu\n"              \
 321                  : type_is(var, char *)         ? "%s\n"                \
 322                  : "%i\n", var)
 323
 324 ssize_t bch2_hprint(char *buf, s64 v);
 325
 326 bool bch2_is_zero(const void *, size_t);
 327
 328 ssize_t bch2_snprint_string_list(char *buf, size_t size, const char * const list[],
 329                             size_t selected);
 330
 331 ssize_t bch2_read_string_list(const char *buf, const char * const list[]);
 332
 333 struct time_stats {
 334         spinlock_t      lock;
 335         u64             count;
 336         /*
 337          * all fields are in nanoseconds, averages are ewmas stored left shifted
 338          * by 8
 339          */
 340         u64             last_duration;
 341         u64             max_duration;
 342         u64             average_duration;
 343         u64             average_frequency;
 344         u64             last;
 345 };
 346
 347 void bch2_time_stats_clear(struct time_stats *stats);
 348 void __bch2_time_stats_update(struct time_stats *stats, u64 time);
 349 void bch2_time_stats_update(struct time_stats *stats, u64 time);
 350
 351 static inline unsigned local_clock_us(void)
 352 {
 353         return local_clock() >> 10;
 354 }
 355
 356 #define NSEC_PER_ns                     1L
 357 #define NSEC_PER_us                     NSEC_PER_USEC
 358 #define NSEC_PER_ms                     NSEC_PER_MSEC
 359 #define NSEC_PER_sec                    NSEC_PER_SEC
 360
 361 #define __print_time_stat(stats, name, stat, units)                     \
 362         sysfs_print(name ## _ ## stat ## _ ## units,                    \
 363                     div_u64((stats)->stat >> 8, NSEC_PER_ ## units))
 364
 365 #define sysfs_print_time_stats(stats, name,                             \
 366                                frequency_units,                         \
 367                                duration_units)                          \
 368 do {                                                                    \
 369         __print_time_stat(stats, name,                                  \
 370                           average_frequency,    frequency_units);       \
 371         __print_time_stat(stats, name,                                  \
 372                           average_duration,     duration_units);        \
 373         sysfs_print(name ## _ ##count, (stats)->count);                 \
 374         sysfs_print(name ## _ ##last_duration ## _ ## duration_units,   \
 375                         div_u64((stats)->last_duration,                 \
 376                                 NSEC_PER_ ## duration_units));          \
 377         sysfs_print(name ## _ ##max_duration ## _ ## duration_units,    \
 378                         div_u64((stats)->max_duration,                  \
 379                                 NSEC_PER_ ## duration_units));          \
 380                                                                         \
 381         sysfs_print(name ## _last_ ## frequency_units, (stats)->last    \
 382                     ? div_s64(local_clock() - (stats)->last,            \
 383                               NSEC_PER_ ## frequency_units)             \
 384                     : -1LL);                                            \
 385 } while (0)
 386
 387 #define sysfs_clear_time_stats(stats, name)                             \
 388 do {                                                                    \
 389         if (attr == &sysfs_ ## name ## _clear)                          \
 390                 bch2_time_stats_clear(stats);                           \
 391 } while (0)
 392
 393 #define sysfs_time_stats_attribute(name,                                \
 394                                    frequency_units,                     \
 395                                    duration_units)                      \
 396 write_attribute(name ## _clear);                                        \
 397 read_attribute(name ## _count);                                         \
 398 read_attribute(name ## _average_frequency_ ## frequency_units);         \
 399 read_attribute(name ## _average_duration_ ## duration_units);           \
 400 read_attribute(name ## _last_duration_ ## duration_units);              \
 401 read_attribute(name ## _max_duration_ ## duration_units);               \
 402 read_attribute(name ## _last_ ## frequency_units)
 403
 404 #define sysfs_time_stats_attribute_list(name,                           \
 405                                         frequency_units,                \
 406                                         duration_units)                 \
 407 &sysfs_ ## name ## _clear,                                              \
 408 &sysfs_ ## name ## _count,                                              \
 409 &sysfs_ ## name ## _average_frequency_ ## frequency_units,              \
 410 &sysfs_ ## name ## _average_duration_ ## duration_units,                \
 411 &sysfs_ ## name ## _last_duration_ ## duration_units,                   \
 412 &sysfs_ ## name ## _max_duration_ ## duration_units,                    \
 413 &sysfs_ ## name ## _last_ ## frequency_units,
 414
 415 #define ewma_add(ewma, val, weight)                                     \
 416 ({                                                                      \
 417         typeof(ewma) _ewma = (ewma);                                    \
 418         typeof(weight) _weight = (weight);                              \
 419                                                                         \
 420         (((_ewma << _weight) - _ewma) + (val)) >> _weight;              \
 421 })
 422
 423 struct bch_ratelimit {
 424         /* Next time we want to do some work, in nanoseconds */
 425         u64                     next;
 426
 427         /*
 428          * Rate at which we want to do work, in units per nanosecond
 429          * The units here correspond to the units passed to
 430          * bch2_ratelimit_increment()
 431          */
 432         unsigned                rate;
 433 };
 434
 435 static inline void bch2_ratelimit_reset(struct bch_ratelimit *d)
 436 {
 437         d->next = local_clock();
 438 }
 439
 440 u64 bch2_ratelimit_delay(struct bch_ratelimit *);
 441 void bch2_ratelimit_increment(struct bch_ratelimit *, u64);
 442 int bch2_ratelimit_wait_freezable_stoppable(struct bch_ratelimit *);
 443
 444 struct bch_pd_controller {
 445         struct bch_ratelimit    rate;
 446         unsigned long           last_update;
 447
 448         s64                     last_actual;
 449         s64                     smoothed_derivative;
 450
 451         unsigned                p_term_inverse;
 452         unsigned                d_smooth;
 453         unsigned                d_term;
 454
 455         /* for exporting to sysfs (no effect on behavior) */
 456         s64                     last_derivative;
 457         s64                     last_proportional;
 458         s64                     last_change;
 459         s64                     last_target;
 460
 461         /* If true, the rate will not increase if bch2_ratelimit_delay()
 462          * is not being called often enough. */
 463         bool                    backpressure;
 464 };
 465
 466 void bch2_pd_controller_update(struct bch_pd_controller *, s64, s64, int);
 467 void bch2_pd_controller_init(struct bch_pd_controller *);
 468 size_t bch2_pd_controller_print_debug(struct bch_pd_controller *, char *);
 469
 470 #define sysfs_pd_controller_attribute(name)                             \
 471         rw_attribute(name##_rate);                                      \
 472         rw_attribute(name##_rate_bytes);                                \
 473         rw_attribute(name##_rate_d_term);                               \
 474         rw_attribute(name##_rate_p_term_inverse);                       \
 475         read_attribute(name##_rate_debug)
 476
 477 #define sysfs_pd_controller_files(name)                                 \
 478         &sysfs_##name##_rate,                                           \
 479         &sysfs_##name##_rate_bytes,                                     \
 480         &sysfs_##name##_rate_d_term,                                    \
 481         &sysfs_##name##_rate_p_term_inverse,                            \
 482         &sysfs_##name##_rate_debug
 483
 484 #define sysfs_pd_controller_show(name, var)                             \
 485 do {                                                                    \
 486         sysfs_hprint(name##_rate,               (var)->rate.rate);      \
 487         sysfs_print(name##_rate_bytes,          (var)->rate.rate);      \
 488         sysfs_print(name##_rate_d_term,         (var)->d_term);         \
 489         sysfs_print(name##_rate_p_term_inverse, (var)->p_term_inverse); \
 490                                                                         \
 491         if (attr == &sysfs_##name##_rate_debug)                         \
 492                 return bch2_pd_controller_print_debug(var, buf);                \
 493 } while (0)
 494
 495 #define sysfs_pd_controller_store(name, var)                            \
 496 do {                                                                    \
 497         sysfs_strtoul_clamp(name##_rate,                                \
 498                             (var)->rate.rate, 1, UINT_MAX);             \
 499         sysfs_strtoul_clamp(name##_rate_bytes,                          \
 500                             (var)->rate.rate, 1, UINT_MAX);             \
 501         sysfs_strtoul(name##_rate_d_term,       (var)->d_term);         \
 502         sysfs_strtoul_clamp(name##_rate_p_term_inverse,                 \
 503                             (var)->p_term_inverse, 1, INT_MAX);         \
 504 } while (0)
 505
 506 #define __DIV_SAFE(n, d, zero)                                          \
 507 ({                                                                      \
 508         typeof(n) _n = (n);                                             \
 509         typeof(d) _d = (d);                                             \
 510         _d ? _n / _d : zero;                                            \
 511 })
 512
 513 #define DIV_SAFE(n, d)  __DIV_SAFE(n, d, 0)
 514
 515 #define container_of_or_null(ptr, type, member)                         \
 516 ({                                                                      \
 517         typeof(ptr) _ptr = ptr;                                         \
 518         _ptr ? container_of(_ptr, type, member) : NULL;                 \
 519 })
 520
 521 #define RB_INSERT(root, new, member, cmp)                               \
 522 ({                                                                      \
 523         __label__ dup;                                                  \
 524         struct rb_node **n = &(root)->rb_node, *parent = NULL;          \
 525         typeof(new) this;                                               \
 526         int res, ret = -1;                                              \
 527                                                                         \
 528         while (*n) {                                                    \
 529                 parent = *n;                                            \
 530                 this = container_of(*n, typeof(*(new)), member);        \
 531                 res = cmp(new, this);                                   \
 532                 if (!res)                                               \
 533                         goto dup;                                       \
 534                 n = res < 0                                             \
 535                         ? &(*n)->rb_left                                \
 536                         : &(*n)->rb_right;                              \
 537         }                                                               \
 538                                                                         \
 539         rb_link_node(&(new)->member, parent, n);                        \
 540         rb_insert_color(&(new)->member, root);                          \
 541         ret = 0;                                                        \
 542 dup:                                                                    \
 543         ret;                                                            \
 544 })
 545
 546 #define RB_SEARCH(root, search, member, cmp)                            \
 547 ({                                                                      \
 548         struct rb_node *n = (root)->rb_node;                            \
 549         typeof(&(search)) this, ret = NULL;                             \
 550         int res;                                                        \
 551                                                                         \
 552         while (n) {                                                     \
 553                 this = container_of(n, typeof(search), member);         \
 554                 res = cmp(&(search), this);                             \
 555                 if (!res) {                                             \
 556                         ret = this;                                     \
 557                         break;                                          \
 558                 }                                                       \
 559                 n = res < 0                                             \
 560                         ? n->rb_left                                    \
 561                         : n->rb_right;                                  \
 562         }                                                               \
 563         ret;                                                            \
 564 })
 565
 566 #define RB_GREATER(root, search, member, cmp)                           \
 567 ({                                                                      \
 568         struct rb_node *n = (root)->rb_node;                            \
 569         typeof(&(search)) this, ret = NULL;                             \
 570         int res;                                                        \
 571                                                                         \
 572         while (n) {                                                     \
 573                 this = container_of(n, typeof(search), member);         \
 574                 res = cmp(&(search), this);                             \
 575                 if (res < 0) {                                          \
 576                         ret = this;                                     \
 577                         n = n->rb_left;                                 \
 578                 } else                                                  \
 579                         n = n->rb_right;                                \
 580         }                                                               \
 581         ret;                                                            \
 582 })
 583
 584 #define RB_FIRST(root, type, member)                                    \
 585         container_of_or_null(rb_first(root), type, member)
 586
 587 #define RB_LAST(root, type, member)                                     \
 588         container_of_or_null(rb_last(root), type, member)
 589
 590 #define RB_NEXT(ptr, member)                                            \
 591         container_of_or_null(rb_next(&(ptr)->member), typeof(*ptr), member)
 592
 593 #define RB_PREV(ptr, member)                                            \
 594         container_of_or_null(rb_prev(&(ptr)->member), typeof(*ptr), member)
 595
 596 /* Does linear interpolation between powers of two */
 597 static inline unsigned fract_exp_two(unsigned x, unsigned fract_bits)
 598 {
 599         unsigned fract = x & ~(~0 << fract_bits);
 600
 601         x >>= fract_bits;
 602         x   = 1 << x;
 603         x  += (x * fract) >> fract_bits;
 604
 605         return x;
 606 }
 607
 608 void bch2_bio_map(struct bio *bio, void *base);
 609
 610 static inline sector_t bdev_sectors(struct block_device *bdev)
 611 {
 612         return bdev->bd_inode->i_size >> 9;
 613 }
 614
 615 #define closure_bio_submit(bio, cl)                                     \
 616 do {                                                                    \
 617         closure_get(cl);                                                \
 618         submit_bio(bio);                                                \
 619 } while (0)
 620
 621 #define kthread_wait_freezable(cond)                                    \
 622 ({                                                                      \
 623         int _ret = 0;                                                   \
 624         while (1) {                                                     \
 625                 set_current_state(TASK_INTERRUPTIBLE);                  \
 626                 if (kthread_should_stop()) {                            \
 627                         _ret = -1;                                      \
 628                         break;                                          \
 629                 }                                                       \
 630                                                                         \
 631                 if (cond)                                               \
 632                         break;                                          \
 633                                                                         \
 634                 schedule();                                             \
 635                 try_to_freeze();                                        \
 636         }                                                               \
 637         set_current_state(TASK_RUNNING);                                \
 638         _ret;                                                           \
 639 })
 640
 641 size_t bch2_rand_range(size_t);
 642
 643 void memcpy_to_bio(struct bio *, struct bvec_iter, void *);
 644 void memcpy_from_bio(void *, struct bio *, struct bvec_iter);
 645
 646 static inline void __memcpy_u64s(void *dst, const void *src,
 647                                  unsigned u64s)
 648 {
 649 #ifdef CONFIG_X86_64
 650         long d0, d1, d2;
 651         asm volatile("rep ; movsq"
 652                      : "=&c" (d0), "=&D" (d1), "=&S" (d2)
 653                      : "0" (u64s), "1" (dst), "2" (src)
 654                      : "memory");
 655 #else
 656         u64 *d = dst;
 657         const u64 *s = src;
 658
 659         while (u64s--)
 660                 *d++ = *s++;
 661 #endif
 662 }
 663
 664 static inline void memcpy_u64s(void *dst, const void *src,
 665                                unsigned u64s)
 666 {
 667         EBUG_ON(!(dst >= src + u64s * sizeof(u64) ||
 668                  dst + u64s * sizeof(u64) <= src));
 669
 670         __memcpy_u64s(dst, src, u64s);
 671 }
 672
 673 static inline void __memmove_u64s_down(void *dst, const void *src,
 674                                        unsigned u64s)
 675 {
 676         __memcpy_u64s(dst, src, u64s);
 677 }
 678
 679 static inline void memmove_u64s_down(void *dst, const void *src,
 680                                      unsigned u64s)
 681 {
 682         EBUG_ON(dst > src);
 683
 684         __memmove_u64s_down(dst, src, u64s);
 685 }
 686
 687 static inline void __memmove_u64s_up(void *_dst, const void *_src,
 688                                      unsigned u64s)
 689 {
 690         u64 *dst = (u64 *) _dst + u64s - 1;
 691         u64 *src = (u64 *) _src + u64s - 1;
 692
 693 #ifdef CONFIG_X86_64
 694         long d0, d1, d2;
 695         asm volatile("std ;\n"
 696                      "rep ; movsq\n"
 697                      "cld ;\n"
 698                      : "=&c" (d0), "=&D" (d1), "=&S" (d2)
 699                      : "0" (u64s), "1" (dst), "2" (src)
 700                      : "memory");
 701 #else
 702         while (u64s--)
 703                 *dst-- = *src--;
 704 #endif
 705 }
 706
 707 static inline void memmove_u64s_up(void *dst, const void *src,
 708                                    unsigned u64s)
 709 {
 710         EBUG_ON(dst < src);
 711
 712         __memmove_u64s_up(dst, src, u64s);
 713 }
 714
 715 static inline void memmove_u64s(void *dst, const void *src,
 716                                 unsigned u64s)
 717 {
 718         if (dst < src)
 719                 __memmove_u64s_down(dst, src, u64s);
 720         else
 721                 __memmove_u64s_up(dst, src, u64s);
 722 }
 723
 724 static inline struct bio_vec next_contig_bvec(struct bio *bio,
 725                                               struct bvec_iter *iter)
 726 {
 727         struct bio_vec bv = bio_iter_iovec(bio, *iter);
 728
 729         bio_advance_iter(bio, iter, bv.bv_len);
 730 #ifndef CONFIG_HIGHMEM
 731         while (iter->bi_size) {
 732                 struct bio_vec next = bio_iter_iovec(bio, *iter);
 733
 734                 if (page_address(bv.bv_page) + bv.bv_offset + bv.bv_len !=
 735                     page_address(next.bv_page) + next.bv_offset)
 736                         break;
 737
 738                 bv.bv_len += next.bv_len;
 739                 bio_advance_iter(bio, iter, next.bv_len);
 740         }
 741 #endif
 742         return bv;
 743 }
 744
 745 #define __bio_for_each_contig_segment(bv, bio, iter, start)             \
 746         for (iter = (start);                                            \
 747              (iter).bi_size &&                                          \
 748                 ((bv = next_contig_bvec((bio), &(iter))), 1);)
 749
 750 #define bio_for_each_contig_segment(bv, bio, iter)                      \
 751         __bio_for_each_contig_segment(bv, bio, iter, (bio)->bi_iter)
 752
 753 #endif /* _BCACHE_UTIL_H */