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

   1 #ifndef _BCACHEFS_UTIL_H
   2 #define _BCACHEFS_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/freezer.h>
   9 #include <linux/kernel.h>
  10 #include <linux/sched/clock.h>
  11 #include <linux/llist.h>
  12 #include <linux/log2.h>
  13 #include <linux/percpu.h>
  14 #include <linux/ratelimit.h>
  15 #include <linux/slab.h>
  16 #include <linux/vmalloc.h>
  17 #include <linux/workqueue.h>
  18
  19 #define PAGE_SECTOR_SHIFT       (PAGE_SHIFT - 9)
  20 #define PAGE_SECTORS            (1UL << PAGE_SECTOR_SHIFT)
  21
  22 struct closure;
  23
  24 #ifdef CONFIG_BCACHEFS_DEBUG
  25
  26 #define EBUG_ON(cond)           BUG_ON(cond)
  27 #define atomic_dec_bug(v)       BUG_ON(atomic_dec_return(v) < 0)
  28 #define atomic_inc_bug(v, i)    BUG_ON(atomic_inc_return(v) <= i)
  29 #define atomic_sub_bug(i, v)    BUG_ON(atomic_sub_return(i, v) < 0)
  30 #define atomic_add_bug(i, v)    BUG_ON(atomic_add_return(i, v) < 0)
  31 #define atomic_long_dec_bug(v)          BUG_ON(atomic_long_dec_return(v) < 0)
  32 #define atomic_long_sub_bug(i, v)       BUG_ON(atomic_long_sub_return(i, v) < 0)
  33 #define atomic64_dec_bug(v)     BUG_ON(atomic64_dec_return(v) < 0)
  34 #define atomic64_inc_bug(v, i)  BUG_ON(atomic64_inc_return(v) <= i)
  35 #define atomic64_sub_bug(i, v)  BUG_ON(atomic64_sub_return(i, v) < 0)
  36 #define atomic64_add_bug(i, v)  BUG_ON(atomic64_add_return(i, v) < 0)
  37
  38 #define memcpy(dst, src, len)                                           \
  39 ({                                                                      \
  40         void *_dst = (dst);                                             \
  41         const void *_src = (src);                                       \
  42         size_t _len = (len);                                            \
  43                                                                         \
  44         BUG_ON(!((void *) (_dst) >= (void *) (_src) + (_len) ||         \
  45                  (void *) (_dst) + (_len) <= (void *) (_src)));         \
  46         memcpy(_dst, _src, _len);                                       \
  47 })
  48
  49 #else /* DEBUG */
  50
  51 #define EBUG_ON(cond)
  52 #define atomic_dec_bug(v)       atomic_dec(v)
  53 #define atomic_inc_bug(v, i)    atomic_inc(v)
  54 #define atomic_sub_bug(i, v)    atomic_sub(i, v)
  55 #define atomic_add_bug(i, v)    atomic_add(i, v)
  56 #define atomic_long_dec_bug(v)          atomic_long_dec(v)
  57 #define atomic_long_sub_bug(i, v)       atomic_long_sub(i, v)
  58 #define atomic64_dec_bug(v)     atomic64_dec(v)
  59 #define atomic64_inc_bug(v, i)  atomic64_inc(v)
  60 #define atomic64_sub_bug(i, v)  atomic64_sub(i, v)
  61 #define atomic64_add_bug(i, v)  atomic64_add(i, v)
  62
  63 #endif
  64
  65 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
  66 #define CPU_BIG_ENDIAN          0
  67 #elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
  68 #define CPU_BIG_ENDIAN          1
  69 #endif
  70
  71 /* type hackery */
  72
  73 #define type_is_exact(_val, _type)                                      \
  74         __builtin_types_compatible_p(typeof(_val), _type)
  75
  76 #define type_is(_val, _type)                                            \
  77         (__builtin_types_compatible_p(typeof(_val), _type) ||           \
  78          __builtin_types_compatible_p(typeof(_val), const _type))
  79
  80 /* Userspace doesn't align allocations as nicely as the kernel allocators: */
  81 static inline size_t buf_pages(void *p, size_t len)
  82 {
  83         return DIV_ROUND_UP(len +
  84                             ((unsigned long) p & (PAGE_SIZE - 1)),
  85                             PAGE_SIZE);
  86 }
  87
  88 static inline void vpfree(void *p, size_t size)
  89 {
  90         if (is_vmalloc_addr(p))
  91                 vfree(p);
  92         else
  93                 free_pages((unsigned long) p, get_order(size));
  94 }
  95
  96 static inline void *vpmalloc(size_t size, gfp_t gfp_mask)
  97 {
  98         return (void *) __get_free_pages(gfp_mask|__GFP_NOWARN,
  99                                          get_order(size)) ?:
 100                 __vmalloc(size, gfp_mask, PAGE_KERNEL);
 101 }
 102
 103 static inline void kvpfree(void *p, size_t size)
 104 {
 105         if (size < PAGE_SIZE)
 106                 kfree(p);
 107         else
 108                 vpfree(p, size);
 109 }
 110
 111 static inline void *kvpmalloc(size_t size, gfp_t gfp_mask)
 112 {
 113         return size < PAGE_SIZE
 114                 ? kmalloc(size, gfp_mask)
 115                 : vpmalloc(size, gfp_mask);
 116 }
 117
 118 int mempool_init_kvpmalloc_pool(mempool_t *, int, size_t);
 119
 120 #define HEAP(type)                                                      \
 121 struct {                                                                \
 122         size_t size, used;                                              \
 123         type *data;                                                     \
 124 }
 125
 126 #define DECLARE_HEAP(type, name) HEAP(type) name
 127
 128 #define init_heap(heap, _size, gfp)                                     \
 129 ({                                                                      \
 130         (heap)->used = 0;                                               \
 131         (heap)->size = (_size);                                         \
 132         (heap)->data = kvpmalloc((heap)->size * sizeof((heap)->data[0]),\
 133                                  (gfp));                                \
 134 })
 135
 136 #define free_heap(heap)                                                 \
 137 do {                                                                    \
 138         kvpfree((heap)->data, (heap)->size * sizeof((heap)->data[0]));  \
 139         (heap)->data = NULL;                                            \
 140 } while (0)
 141
 142 #define heap_set_backpointer(h, i, _fn)                                 \
 143 do {                                                                    \
 144         void (*fn)(typeof(h), size_t) = _fn;                            \
 145         if (fn)                                                         \
 146                 fn(h, i);                                               \
 147 } while (0)
 148
 149 #define heap_swap(h, i, j, set_backpointer)                             \
 150 do {                                                                    \
 151         swap((h)->data[i], (h)->data[j]);                               \
 152         heap_set_backpointer(h, i, set_backpointer);                    \
 153         heap_set_backpointer(h, j, set_backpointer);                    \
 154 } while (0)
 155
 156 #define heap_peek(h)                                                    \
 157 ({                                                                      \
 158         EBUG_ON(!(h)->used);                                            \
 159         (h)->data[0];                                                   \
 160 })
 161
 162 #define heap_full(h)    ((h)->used == (h)->size)
 163
 164 #define heap_sift_down(h, i, cmp, set_backpointer)                      \
 165 do {                                                                    \
 166         size_t _c, _j = i;                                              \
 167                                                                         \
 168         for (; _j * 2 + 1 < (h)->used; _j = _c) {                       \
 169                 _c = _j * 2 + 1;                                        \
 170                 if (_c + 1 < (h)->used &&                               \
 171                     cmp(h, (h)->data[_c], (h)->data[_c + 1]) >= 0)      \
 172                         _c++;                                           \
 173                                                                         \
 174                 if (cmp(h, (h)->data[_c], (h)->data[_j]) >= 0)          \
 175                         break;                                          \
 176                 heap_swap(h, _c, _j, set_backpointer);                  \
 177         }                                                               \
 178 } while (0)
 179
 180 #define heap_sift_up(h, i, cmp, set_backpointer)                        \
 181 do {                                                                    \
 182         while (i) {                                                     \
 183                 size_t p = (i - 1) / 2;                                 \
 184                 if (cmp(h, (h)->data[i], (h)->data[p]) >= 0)            \
 185                         break;                                          \
 186                 heap_swap(h, i, p, set_backpointer);                    \
 187                 i = p;                                                  \
 188         }                                                               \
 189 } while (0)
 190
 191 #define __heap_add(h, d, cmp, set_backpointer)                          \
 192 ({                                                                      \
 193         size_t _i = (h)->used++;                                        \
 194         (h)->data[_i] = d;                                              \
 195         heap_set_backpointer(h, _i, set_backpointer);                   \
 196                                                                         \
 197         heap_sift_up(h, _i, cmp, set_backpointer);                      \
 198         _i;                                                             \
 199 })
 200
 201 #define heap_add(h, d, cmp, set_backpointer)                            \
 202 ({                                                                      \
 203         bool _r = !heap_full(h);                                        \
 204         if (_r)                                                         \
 205                 __heap_add(h, d, cmp, set_backpointer);                 \
 206         _r;                                                             \
 207 })
 208
 209 #define heap_add_or_replace(h, new, cmp, set_backpointer)               \
 210 do {                                                                    \
 211         if (!heap_add(h, new, cmp, set_backpointer) &&                  \
 212             cmp(h, new, heap_peek(h)) >= 0) {                           \
 213                 (h)->data[0] = new;                                     \
 214                 heap_set_backpointer(h, 0, set_backpointer);            \
 215                 heap_sift_down(h, 0, cmp, set_backpointer);             \
 216         }                                                               \
 217 } while (0)
 218
 219 #define heap_del(h, i, cmp, set_backpointer)                            \
 220 do {                                                                    \
 221         size_t _i = (i);                                                \
 222                                                                         \
 223         BUG_ON(_i >= (h)->used);                                        \
 224         (h)->used--;                                                    \
 225         heap_swap(h, _i, (h)->used, set_backpointer);                   \
 226         heap_sift_up(h, _i, cmp, set_backpointer);                      \
 227         heap_sift_down(h, _i, cmp, set_backpointer);                    \
 228 } while (0)
 229
 230 #define heap_pop(h, d, cmp, set_backpointer)                            \
 231 ({                                                                      \
 232         bool _r = (h)->used;                                            \
 233         if (_r) {                                                       \
 234                 (d) = (h)->data[0];                                     \
 235                 heap_del(h, 0, cmp, set_backpointer);                   \
 236         }                                                               \
 237         _r;                                                             \
 238 })
 239
 240 #define heap_resort(heap, cmp, set_backpointer)                         \
 241 do {                                                                    \
 242         ssize_t _i;                                                     \
 243         for (_i = (ssize_t) (heap)->used / 2 -  1; _i >= 0; --_i)       \
 244                 heap_sift_down(heap, _i, cmp, set_backpointer);         \
 245 } while (0)
 246
 247 #define ANYSINT_MAX(t)                                                  \
 248         ((((t) 1 << (sizeof(t) * 8 - 2)) - (t) 1) * (t) 2 + (t) 1)
 249
 250 struct printbuf {
 251         char            *pos;
 252         char            *end;
 253 };
 254
 255 static inline size_t printbuf_remaining(struct printbuf *buf)
 256 {
 257         return buf->end - buf->pos;
 258 }
 259
 260 #define _PBUF(_buf, _len)                                               \
 261         ((struct printbuf) {                                            \
 262                 .pos    = _buf,                                         \
 263                 .end    = _buf + _len,                                  \
 264         })
 265
 266 #define PBUF(_buf) _PBUF(_buf, sizeof(_buf))
 267
 268 #define pr_buf(_out, ...)                                               \
 269 do {                                                                    \
 270         (_out)->pos += scnprintf((_out)->pos, printbuf_remaining(_out), \
 271                                  __VA_ARGS__);                          \
 272 } while (0)
 273
 274 void bch_scnmemcpy(struct printbuf *, const char *, size_t);
 275
 276 int bch2_strtoint_h(const char *, int *);
 277 int bch2_strtouint_h(const char *, unsigned int *);
 278 int bch2_strtoll_h(const char *, long long *);
 279 int bch2_strtoull_h(const char *, unsigned long long *);
 280 int bch2_strtou64_h(const char *, u64 *);
 281
 282 static inline int bch2_strtol_h(const char *cp, long *res)
 283 {
 284 #if BITS_PER_LONG == 32
 285         return bch2_strtoint_h(cp, (int *) res);
 286 #else
 287         return bch2_strtoll_h(cp, (long long *) res);
 288 #endif
 289 }
 290
 291 static inline int bch2_strtoul_h(const char *cp, long *res)
 292 {
 293 #if BITS_PER_LONG == 32
 294         return bch2_strtouint_h(cp, (unsigned int *) res);
 295 #else
 296         return bch2_strtoull_h(cp, (unsigned long long *) res);
 297 #endif
 298 }
 299
 300 #define strtoi_h(cp, res)                                               \
 301         ( type_is(*res, int)            ? bch2_strtoint_h(cp, (void *) res)\
 302         : type_is(*res, long)           ? bch2_strtol_h(cp, (void *) res)\
 303         : type_is(*res, long long)      ? bch2_strtoll_h(cp, (void *) res)\
 304         : type_is(*res, unsigned)       ? bch2_strtouint_h(cp, (void *) res)\
 305         : type_is(*res, unsigned long)  ? bch2_strtoul_h(cp, (void *) res)\
 306         : type_is(*res, unsigned long long) ? bch2_strtoull_h(cp, (void *) res)\
 307         : -EINVAL)
 308
 309 #define strtoul_safe(cp, var)                                           \
 310 ({                                                                      \
 311         unsigned long _v;                                               \
 312         int _r = kstrtoul(cp, 10, &_v);                                 \
 313         if (!_r)                                                        \
 314                 var = _v;                                               \
 315         _r;                                                             \
 316 })
 317
 318 #define strtoul_safe_clamp(cp, var, min, max)                           \
 319 ({                                                                      \
 320         unsigned long _v;                                               \
 321         int _r = kstrtoul(cp, 10, &_v);                                 \
 322         if (!_r)                                                        \
 323                 var = clamp_t(typeof(var), _v, min, max);               \
 324         _r;                                                             \
 325 })
 326
 327 #define strtoul_safe_restrict(cp, var, min, max)                        \
 328 ({                                                                      \
 329         unsigned long _v;                                               \
 330         int _r = kstrtoul(cp, 10, &_v);                                 \
 331         if (!_r && _v >= min && _v <= max)                              \
 332                 var = _v;                                               \
 333         else                                                            \
 334                 _r = -EINVAL;                                           \
 335         _r;                                                             \
 336 })
 337
 338 #define snprint(buf, size, var)                                         \
 339         snprintf(buf, size,                                             \
 340                    type_is(var, int)            ? "%i\n"                \
 341                  : type_is(var, unsigned)       ? "%u\n"                \
 342                  : type_is(var, long)           ? "%li\n"               \
 343                  : type_is(var, unsigned long)  ? "%lu\n"               \
 344                  : type_is(var, s64)            ? "%lli\n"              \
 345                  : type_is(var, u64)            ? "%llu\n"              \
 346                  : type_is(var, char *)         ? "%s\n"                \
 347                  : "%i\n", var)
 348
 349 void bch2_hprint(struct printbuf *, s64);
 350
 351 bool bch2_is_zero(const void *, size_t);
 352
 353 void bch2_string_opt_to_text(struct printbuf *,
 354                              const char * const [], size_t);
 355
 356 void bch2_flags_to_text(struct printbuf *, const char * const[], u64);
 357 u64 bch2_read_flag_list(char *, const char * const[]);
 358
 359 #define NR_QUANTILES    15
 360 #define QUANTILE_IDX(i) inorder_to_eytzinger0(i, NR_QUANTILES)
 361 #define QUANTILE_FIRST  eytzinger0_first(NR_QUANTILES)
 362 #define QUANTILE_LAST   eytzinger0_last(NR_QUANTILES)
 363
 364 struct quantiles {
 365         struct quantile_entry {
 366                 u64     m;
 367                 u64     step;
 368         }               entries[NR_QUANTILES];
 369 };
 370
 371 struct time_stat_buffer {
 372         unsigned        nr;
 373         struct time_stat_buffer_entry {
 374                 u64     start;
 375                 u64     end;
 376         }               entries[32];
 377 };
 378
 379 struct time_stats {
 380         spinlock_t      lock;
 381         u64             count;
 382         /* all fields are in nanoseconds */
 383         u64             average_duration;
 384         u64             average_frequency;
 385         u64             max_duration;
 386         u64             last_event;
 387         struct quantiles quantiles;
 388
 389         struct time_stat_buffer __percpu *buffer;
 390 };
 391
 392 void __bch2_time_stats_update(struct time_stats *stats, u64, u64);
 393
 394 static inline void bch2_time_stats_update(struct time_stats *stats, u64 start)
 395 {
 396         __bch2_time_stats_update(stats, start, local_clock());
 397 }
 398
 399 size_t bch2_time_stats_print(struct time_stats *, char *, size_t);
 400
 401 void bch2_time_stats_exit(struct time_stats *);
 402 void bch2_time_stats_init(struct time_stats *);
 403
 404 #define ewma_add(ewma, val, weight)                                     \
 405 ({                                                                      \
 406         typeof(ewma) _ewma = (ewma);                                    \
 407         typeof(weight) _weight = (weight);                              \
 408                                                                         \
 409         (((_ewma << _weight) - _ewma) + (val)) >> _weight;              \
 410 })
 411
 412 struct bch_ratelimit {
 413         /* Next time we want to do some work, in nanoseconds */
 414         u64                     next;
 415
 416         /*
 417          * Rate at which we want to do work, in units per nanosecond
 418          * The units here correspond to the units passed to
 419          * bch2_ratelimit_increment()
 420          */
 421         unsigned                rate;
 422 };
 423
 424 static inline void bch2_ratelimit_reset(struct bch_ratelimit *d)
 425 {
 426         d->next = local_clock();
 427 }
 428
 429 u64 bch2_ratelimit_delay(struct bch_ratelimit *);
 430 void bch2_ratelimit_increment(struct bch_ratelimit *, u64);
 431
 432 struct bch_pd_controller {
 433         struct bch_ratelimit    rate;
 434         unsigned long           last_update;
 435
 436         s64                     last_actual;
 437         s64                     smoothed_derivative;
 438
 439         unsigned                p_term_inverse;
 440         unsigned                d_smooth;
 441         unsigned                d_term;
 442
 443         /* for exporting to sysfs (no effect on behavior) */
 444         s64                     last_derivative;
 445         s64                     last_proportional;
 446         s64                     last_change;
 447         s64                     last_target;
 448
 449         /* If true, the rate will not increase if bch2_ratelimit_delay()
 450          * is not being called often enough. */
 451         bool                    backpressure;
 452 };
 453
 454 void bch2_pd_controller_update(struct bch_pd_controller *, s64, s64, int);
 455 void bch2_pd_controller_init(struct bch_pd_controller *);
 456 size_t bch2_pd_controller_print_debug(struct bch_pd_controller *, char *);
 457
 458 #define sysfs_pd_controller_attribute(name)                             \
 459         rw_attribute(name##_rate);                                      \
 460         rw_attribute(name##_rate_bytes);                                \
 461         rw_attribute(name##_rate_d_term);                               \
 462         rw_attribute(name##_rate_p_term_inverse);                       \
 463         read_attribute(name##_rate_debug)
 464
 465 #define sysfs_pd_controller_files(name)                                 \
 466         &sysfs_##name##_rate,                                           \
 467         &sysfs_##name##_rate_bytes,                                     \
 468         &sysfs_##name##_rate_d_term,                                    \
 469         &sysfs_##name##_rate_p_term_inverse,                            \
 470         &sysfs_##name##_rate_debug
 471
 472 #define sysfs_pd_controller_show(name, var)                             \
 473 do {                                                                    \
 474         sysfs_hprint(name##_rate,               (var)->rate.rate);      \
 475         sysfs_print(name##_rate_bytes,          (var)->rate.rate);      \
 476         sysfs_print(name##_rate_d_term,         (var)->d_term);         \
 477         sysfs_print(name##_rate_p_term_inverse, (var)->p_term_inverse); \
 478                                                                         \
 479         if (attr == &sysfs_##name##_rate_debug)                         \
 480                 return bch2_pd_controller_print_debug(var, buf);                \
 481 } while (0)
 482
 483 #define sysfs_pd_controller_store(name, var)                            \
 484 do {                                                                    \
 485         sysfs_strtoul_clamp(name##_rate,                                \
 486                             (var)->rate.rate, 1, UINT_MAX);             \
 487         sysfs_strtoul_clamp(name##_rate_bytes,                          \
 488                             (var)->rate.rate, 1, UINT_MAX);             \
 489         sysfs_strtoul(name##_rate_d_term,       (var)->d_term);         \
 490         sysfs_strtoul_clamp(name##_rate_p_term_inverse,                 \
 491                             (var)->p_term_inverse, 1, INT_MAX);         \
 492 } while (0)
 493
 494 #define container_of_or_null(ptr, type, member)                         \
 495 ({                                                                      \
 496         typeof(ptr) _ptr = ptr;                                         \
 497         _ptr ? container_of(_ptr, type, member) : NULL;                 \
 498 })
 499
 500 /* Does linear interpolation between powers of two */
 501 static inline unsigned fract_exp_two(unsigned x, unsigned fract_bits)
 502 {
 503         unsigned fract = x & ~(~0 << fract_bits);
 504
 505         x >>= fract_bits;
 506         x   = 1 << x;
 507         x  += (x * fract) >> fract_bits;
 508
 509         return x;
 510 }
 511
 512 void bch2_bio_map(struct bio *bio, void *base);
 513 int bch2_bio_alloc_pages(struct bio *bio, gfp_t gfp_mask);
 514
 515 static inline sector_t bdev_sectors(struct block_device *bdev)
 516 {
 517         return bdev->bd_inode->i_size >> 9;
 518 }
 519
 520 #define closure_bio_submit(bio, cl)                                     \
 521 do {                                                                    \
 522         closure_get(cl);                                                \
 523         submit_bio(bio);                                                \
 524 } while (0)
 525
 526 #define kthread_wait_freezable(cond)                                    \
 527 ({                                                                      \
 528         int _ret = 0;                                                   \
 529         while (1) {                                                     \
 530                 set_current_state(TASK_INTERRUPTIBLE);                  \
 531                 if (kthread_should_stop()) {                            \
 532                         _ret = -1;                                      \
 533                         break;                                          \
 534                 }                                                       \
 535                                                                         \
 536                 if (cond)                                               \
 537                         break;                                          \
 538                                                                         \
 539                 schedule();                                             \
 540                 try_to_freeze();                                        \
 541         }                                                               \
 542         set_current_state(TASK_RUNNING);                                \
 543         _ret;                                                           \
 544 })
 545
 546 size_t bch2_rand_range(size_t);
 547
 548 void memcpy_to_bio(struct bio *, struct bvec_iter, void *);
 549 void memcpy_from_bio(void *, struct bio *, struct bvec_iter);
 550
 551 static inline void __memcpy_u64s(void *dst, const void *src,
 552                                  unsigned u64s)
 553 {
 554 #ifdef CONFIG_X86_64
 555         long d0, d1, d2;
 556         asm volatile("rep ; movsq"
 557                      : "=&c" (d0), "=&D" (d1), "=&S" (d2)
 558                      : "0" (u64s), "1" (dst), "2" (src)
 559                      : "memory");
 560 #else
 561         u64 *d = dst;
 562         const u64 *s = src;
 563
 564         while (u64s--)
 565                 *d++ = *s++;
 566 #endif
 567 }
 568
 569 static inline void memcpy_u64s(void *dst, const void *src,
 570                                unsigned u64s)
 571 {
 572         EBUG_ON(!(dst >= src + u64s * sizeof(u64) ||
 573                  dst + u64s * sizeof(u64) <= src));
 574
 575         __memcpy_u64s(dst, src, u64s);
 576 }
 577
 578 static inline void __memmove_u64s_down(void *dst, const void *src,
 579                                        unsigned u64s)
 580 {
 581         __memcpy_u64s(dst, src, u64s);
 582 }
 583
 584 static inline void memmove_u64s_down(void *dst, const void *src,
 585                                      unsigned u64s)
 586 {
 587         EBUG_ON(dst > src);
 588
 589         __memmove_u64s_down(dst, src, u64s);
 590 }
 591
 592 static inline void __memmove_u64s_up(void *_dst, const void *_src,
 593                                      unsigned u64s)
 594 {
 595         u64 *dst = (u64 *) _dst + u64s - 1;
 596         u64 *src = (u64 *) _src + u64s - 1;
 597
 598 #ifdef CONFIG_X86_64
 599         long d0, d1, d2;
 600         asm volatile("std ;\n"
 601                      "rep ; movsq\n"
 602                      "cld ;\n"
 603                      : "=&c" (d0), "=&D" (d1), "=&S" (d2)
 604                      : "0" (u64s), "1" (dst), "2" (src)
 605                      : "memory");
 606 #else
 607         while (u64s--)
 608                 *dst-- = *src--;
 609 #endif
 610 }
 611
 612 static inline void memmove_u64s_up(void *dst, const void *src,
 613                                    unsigned u64s)
 614 {
 615         EBUG_ON(dst < src);
 616
 617         __memmove_u64s_up(dst, src, u64s);
 618 }
 619
 620 static inline void memmove_u64s(void *dst, const void *src,
 621                                 unsigned u64s)
 622 {
 623         if (dst < src)
 624                 __memmove_u64s_down(dst, src, u64s);
 625         else
 626                 __memmove_u64s_up(dst, src, u64s);
 627 }
 628
 629 static inline struct bio_vec next_contig_bvec(struct bio *bio,
 630                                               struct bvec_iter *iter)
 631 {
 632         struct bio_vec bv = bio_iter_iovec(bio, *iter);
 633
 634         bio_advance_iter(bio, iter, bv.bv_len);
 635 #ifndef CONFIG_HIGHMEM
 636         while (iter->bi_size) {
 637                 struct bio_vec next = bio_iter_iovec(bio, *iter);
 638
 639                 if (page_address(bv.bv_page) + bv.bv_offset + bv.bv_len !=
 640                     page_address(next.bv_page) + next.bv_offset)
 641                         break;
 642
 643                 bv.bv_len += next.bv_len;
 644                 bio_advance_iter(bio, iter, next.bv_len);
 645         }
 646 #endif
 647         return bv;
 648 }
 649
 650 #define __bio_for_each_contig_segment(bv, bio, iter, start)             \
 651         for (iter = (start);                                            \
 652              (iter).bi_size &&                                          \
 653                 ((bv = next_contig_bvec((bio), &(iter))), 1);)
 654
 655 #define bio_for_each_contig_segment(bv, bio, iter)                      \
 656         __bio_for_each_contig_segment(bv, bio, iter, (bio)->bi_iter)
 657
 658 void sort_cmp_size(void *base, size_t num, size_t size,
 659           int (*cmp_func)(const void *, const void *, size_t),
 660           void (*swap_func)(void *, void *, size_t));
 661
 662 /* just the memmove, doesn't update @_nr */
 663 #define __array_insert_item(_array, _nr, _pos)                          \
 664         memmove(&(_array)[(_pos) + 1],                                  \
 665                 &(_array)[(_pos)],                                      \
 666                 sizeof((_array)[0]) * ((_nr) - (_pos)))
 667
 668 #define array_insert_item(_array, _nr, _pos, _new_item)                 \
 669 do {                                                                    \
 670         __array_insert_item(_array, _nr, _pos);                         \
 671         (_nr)++;                                                        \
 672         (_array)[(_pos)] = (_new_item);                                 \
 673 } while (0)
 674
 675 #define array_remove_items(_array, _nr, _pos, _nr_to_remove)            \
 676 do {                                                                    \
 677         (_nr) -= (_nr_to_remove);                                       \
 678         memmove(&(_array)[(_pos)],                                      \
 679                 &(_array)[(_pos) + (_nr_to_remove)],                    \
 680                 sizeof((_array)[0]) * ((_nr) - (_pos)));                \
 681 } while (0)
 682
 683 #define array_remove_item(_array, _nr, _pos)                            \
 684         array_remove_items(_array, _nr, _pos, 1)
 685
 686 #define bubble_sort(_base, _nr, _cmp)                                   \
 687 do {                                                                    \
 688         ssize_t _i, _end;                                               \
 689         bool _swapped = true;                                           \
 690                                                                         \
 691         for (_end = (ssize_t) (_nr) - 1; _end > 0 && _swapped; --_end) {\
 692                 _swapped = false;                                       \
 693                 for (_i = 0; _i < _end; _i++)                           \
 694                         if (_cmp((_base)[_i], (_base)[_i + 1]) > 0) {   \
 695                                 swap((_base)[_i], (_base)[_i + 1]);     \
 696                                 _swapped = true;                        \
 697                         }                                               \
 698         }                                                               \
 699 } while (0)
 700
 701 static inline void acc_u64s(u64 *acc, const u64 *src, unsigned nr)
 702 {
 703         unsigned i;
 704
 705         for (i = 0; i < nr; i++)
 706                 acc[i] += src[i];
 707 }
 708
 709 static inline void acc_u64s_percpu(u64 *acc, const u64 __percpu *src,
 710                                    unsigned nr)
 711 {
 712         int cpu;
 713
 714         for_each_possible_cpu(cpu)
 715                 acc_u64s(acc, per_cpu_ptr(src, cpu), nr);
 716 }
 717
 718 u64 *bch2_acc_percpu_u64s(u64 __percpu *, unsigned);
 719
 720 #endif /* _BCACHEFS_UTIL_H */