fs/bcachefs/util.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _BCACHEFS_UTIL_H
   3 #define _BCACHEFS_UTIL_H
   4
   5 #include <linux/bio.h>
   6 #include <linux/blkdev.h>
   7 #include <linux/closure.h>
   8 #include <linux/errno.h>
   9 #include <linux/freezer.h>
  10 #include <linux/kernel.h>
  11 #include <linux/min_heap.h>
  12 #include <linux/sched/clock.h>
  13 #include <linux/llist.h>
  14 #include <linux/log2.h>
  15 #include <linux/percpu.h>
  16 #include <linux/preempt.h>
  17 #include <linux/ratelimit.h>
  18 #include <linux/slab.h>
  19 #include <linux/vmalloc.h>
  20 #include <linux/workqueue.h>
  21
  22 #include "mean_and_variance.h"
  23
  24 #include "darray.h"
  25 #include "time_stats.h"
  26
  27 struct closure;
  28
  29 #ifdef CONFIG_BCACHEFS_DEBUG
  30 #define EBUG_ON(cond)           BUG_ON(cond)
  31 #else
  32 #define EBUG_ON(cond)
  33 #endif
  34
  35 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
  36 #define CPU_BIG_ENDIAN          0
  37 #elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
  38 #define CPU_BIG_ENDIAN          1
  39 #endif
  40
  41 /* type hackery */
  42
  43 #define type_is_exact(_val, _type)                                      \
  44         __builtin_types_compatible_p(typeof(_val), _type)
  45
  46 #define type_is(_val, _type)                                            \
  47         (__builtin_types_compatible_p(typeof(_val), _type) ||           \
  48          __builtin_types_compatible_p(typeof(_val), const _type))
  49
  50 /* Userspace doesn't align allocations as nicely as the kernel allocators: */
  51 static inline size_t buf_pages(void *p, size_t len)
  52 {
  53         return DIV_ROUND_UP(len +
  54                             ((unsigned long) p & (PAGE_SIZE - 1)),
  55                             PAGE_SIZE);
  56 }
  57
  58 #define init_heap(heap, _size, gfp)                                     \
  59 ({                                                                      \
  60         (heap)->nr = 0;                                         \
  61         (heap)->size = (_size);                                         \
  62         (heap)->data = kvmalloc((heap)->size * sizeof((heap)->data[0]),\
  63                                  (gfp));                                \
  64 })
  65
  66 #define free_heap(heap)                                                 \
  67 do {                                                                    \
  68         kvfree((heap)->data);                                           \
  69         (heap)->data = NULL;                                            \
  70 } while (0)
  71
  72 #define ANYSINT_MAX(t)                                                  \
  73         ((((t) 1 << (sizeof(t) * 8 - 2)) - (t) 1) * (t) 2 + (t) 1)
  74
  75 #include "printbuf.h"
  76
  77 #define prt_vprintf(_out, ...)          bch2_prt_vprintf(_out, __VA_ARGS__)
  78 #define prt_printf(_out, ...)           bch2_prt_printf(_out, __VA_ARGS__)
  79 #define printbuf_str(_buf)              bch2_printbuf_str(_buf)
  80 #define printbuf_exit(_buf)             bch2_printbuf_exit(_buf)
  81
  82 #define printbuf_tabstops_reset(_buf)   bch2_printbuf_tabstops_reset(_buf)
  83 #define printbuf_tabstop_pop(_buf)      bch2_printbuf_tabstop_pop(_buf)
  84 #define printbuf_tabstop_push(_buf, _n) bch2_printbuf_tabstop_push(_buf, _n)
  85
  86 #define printbuf_indent_add(_out, _n)   bch2_printbuf_indent_add(_out, _n)
  87 #define printbuf_indent_sub(_out, _n)   bch2_printbuf_indent_sub(_out, _n)
  88
  89 #define prt_newline(_out)               bch2_prt_newline(_out)
  90 #define prt_tab(_out)                   bch2_prt_tab(_out)
  91 #define prt_tab_rjust(_out)             bch2_prt_tab_rjust(_out)
  92
  93 #define prt_bytes_indented(...)         bch2_prt_bytes_indented(__VA_ARGS__)
  94 #define prt_u64(_out, _v)               prt_printf(_out, "%llu", (u64) (_v))
  95 #define prt_human_readable_u64(...)     bch2_prt_human_readable_u64(__VA_ARGS__)
  96 #define prt_human_readable_s64(...)     bch2_prt_human_readable_s64(__VA_ARGS__)
  97 #define prt_units_u64(...)              bch2_prt_units_u64(__VA_ARGS__)
  98 #define prt_units_s64(...)              bch2_prt_units_s64(__VA_ARGS__)
  99 #define prt_string_option(...)          bch2_prt_string_option(__VA_ARGS__)
 100 #define prt_bitflags(...)               bch2_prt_bitflags(__VA_ARGS__)
 101 #define prt_bitflags_vector(...)        bch2_prt_bitflags_vector(__VA_ARGS__)
 102
 103 void bch2_pr_time_units(struct printbuf *, u64);
 104 void bch2_prt_datetime(struct printbuf *, time64_t);
 105
 106 #ifdef __KERNEL__
 107 static inline void uuid_unparse_lower(u8 *uuid, char *out)
 108 {
 109         sprintf(out, "%pUb", uuid);
 110 }
 111 #else
 112 #include <uuid/uuid.h>
 113 #endif
 114
 115 static inline void pr_uuid(struct printbuf *out, u8 *uuid)
 116 {
 117         char uuid_str[40];
 118
 119         uuid_unparse_lower(uuid, uuid_str);
 120         prt_printf(out, "%s", uuid_str);
 121 }
 122
 123 int bch2_strtoint_h(const char *, int *);
 124 int bch2_strtouint_h(const char *, unsigned int *);
 125 int bch2_strtoll_h(const char *, long long *);
 126 int bch2_strtoull_h(const char *, unsigned long long *);
 127 int bch2_strtou64_h(const char *, u64 *);
 128
 129 static inline int bch2_strtol_h(const char *cp, long *res)
 130 {
 131 #if BITS_PER_LONG == 32
 132         return bch2_strtoint_h(cp, (int *) res);
 133 #else
 134         return bch2_strtoll_h(cp, (long long *) res);
 135 #endif
 136 }
 137
 138 static inline int bch2_strtoul_h(const char *cp, long *res)
 139 {
 140 #if BITS_PER_LONG == 32
 141         return bch2_strtouint_h(cp, (unsigned int *) res);
 142 #else
 143         return bch2_strtoull_h(cp, (unsigned long long *) res);
 144 #endif
 145 }
 146
 147 #define strtoi_h(cp, res)                                               \
 148         ( type_is(*res, int)            ? bch2_strtoint_h(cp, (void *) res)\
 149         : type_is(*res, long)           ? bch2_strtol_h(cp, (void *) res)\
 150         : type_is(*res, long long)      ? bch2_strtoll_h(cp, (void *) res)\
 151         : type_is(*res, unsigned)       ? bch2_strtouint_h(cp, (void *) res)\
 152         : type_is(*res, unsigned long)  ? bch2_strtoul_h(cp, (void *) res)\
 153         : type_is(*res, unsigned long long) ? bch2_strtoull_h(cp, (void *) res)\
 154         : -EINVAL)
 155
 156 #define strtoul_safe(cp, var)                                           \
 157 ({                                                                      \
 158         unsigned long _v;                                               \
 159         int _r = kstrtoul(cp, 10, &_v);                                 \
 160         if (!_r)                                                        \
 161                 var = _v;                                               \
 162         _r;                                                             \
 163 })
 164
 165 #define strtoul_safe_clamp(cp, var, min, max)                           \
 166 ({                                                                      \
 167         unsigned long _v;                                               \
 168         int _r = kstrtoul(cp, 10, &_v);                                 \
 169         if (!_r)                                                        \
 170                 var = clamp_t(typeof(var), _v, min, max);               \
 171         _r;                                                             \
 172 })
 173
 174 #define strtoul_safe_restrict(cp, var, min, max)                        \
 175 ({                                                                      \
 176         unsigned long _v;                                               \
 177         int _r = kstrtoul(cp, 10, &_v);                                 \
 178         if (!_r && _v >= min && _v <= max)                              \
 179                 var = _v;                                               \
 180         else                                                            \
 181                 _r = -EINVAL;                                           \
 182         _r;                                                             \
 183 })
 184
 185 #define snprint(out, var)                                               \
 186         prt_printf(out,                                                 \
 187                    type_is(var, int)            ? "%i\n"                \
 188                  : type_is(var, unsigned)       ? "%u\n"                \
 189                  : type_is(var, long)           ? "%li\n"               \
 190                  : type_is(var, unsigned long)  ? "%lu\n"               \
 191                  : type_is(var, s64)            ? "%lli\n"              \
 192                  : type_is(var, u64)            ? "%llu\n"              \
 193                  : type_is(var, char *)         ? "%s\n"                \
 194                  : "%i\n", var)
 195
 196 bool bch2_is_zero(const void *, size_t);
 197
 198 u64 bch2_read_flag_list(const char *, const char * const[]);
 199
 200 void bch2_prt_u64_base2_nbits(struct printbuf *, u64, unsigned);
 201 void bch2_prt_u64_base2(struct printbuf *, u64);
 202
 203 void bch2_print_string_as_lines(const char *prefix, const char *lines);
 204 void bch2_print_string_as_lines_nonblocking(const char *prefix, const char *lines);
 205
 206 typedef DARRAY(unsigned long) bch_stacktrace;
 207 int bch2_save_backtrace(bch_stacktrace *stack, struct task_struct *, unsigned, gfp_t);
 208 void bch2_prt_backtrace(struct printbuf *, bch_stacktrace *);
 209 int bch2_prt_task_backtrace(struct printbuf *, struct task_struct *, unsigned, gfp_t);
 210
 211 static inline void prt_bdevname(struct printbuf *out, struct block_device *bdev)
 212 {
 213 #ifdef __KERNEL__
 214         prt_printf(out, "%pg", bdev);
 215 #else
 216         prt_str(out, bdev->name);
 217 #endif
 218 }
 219
 220 void bch2_time_stats_to_text(struct printbuf *, struct bch2_time_stats *);
 221
 222 #define ewma_add(ewma, val, weight)                                     \
 223 ({                                                                      \
 224         typeof(ewma) _ewma = (ewma);                                    \
 225         typeof(weight) _weight = (weight);                              \
 226                                                                         \
 227         (((_ewma << _weight) - _ewma) + (val)) >> _weight;              \
 228 })
 229
 230 struct bch_ratelimit {
 231         /* Next time we want to do some work, in nanoseconds */
 232         u64                     next;
 233
 234         /*
 235          * Rate at which we want to do work, in units per nanosecond
 236          * The units here correspond to the units passed to
 237          * bch2_ratelimit_increment()
 238          */
 239         unsigned                rate;
 240 };
 241
 242 static inline void bch2_ratelimit_reset(struct bch_ratelimit *d)
 243 {
 244         d->next = local_clock();
 245 }
 246
 247 u64 bch2_ratelimit_delay(struct bch_ratelimit *);
 248 void bch2_ratelimit_increment(struct bch_ratelimit *, u64);
 249
 250 struct bch_pd_controller {
 251         struct bch_ratelimit    rate;
 252         unsigned long           last_update;
 253
 254         s64                     last_actual;
 255         s64                     smoothed_derivative;
 256
 257         unsigned                p_term_inverse;
 258         unsigned                d_smooth;
 259         unsigned                d_term;
 260
 261         /* for exporting to sysfs (no effect on behavior) */
 262         s64                     last_derivative;
 263         s64                     last_proportional;
 264         s64                     last_change;
 265         s64                     last_target;
 266
 267         /*
 268          * If true, the rate will not increase if bch2_ratelimit_delay()
 269          * is not being called often enough.
 270          */
 271         bool                    backpressure;
 272 };
 273
 274 void bch2_pd_controller_update(struct bch_pd_controller *, s64, s64, int);
 275 void bch2_pd_controller_init(struct bch_pd_controller *);
 276 void bch2_pd_controller_debug_to_text(struct printbuf *, struct bch_pd_controller *);
 277
 278 #define sysfs_pd_controller_attribute(name)                             \
 279         rw_attribute(name##_rate);                                      \
 280         rw_attribute(name##_rate_bytes);                                \
 281         rw_attribute(name##_rate_d_term);                               \
 282         rw_attribute(name##_rate_p_term_inverse);                       \
 283         read_attribute(name##_rate_debug)
 284
 285 #define sysfs_pd_controller_files(name)                                 \
 286         &sysfs_##name##_rate,                                           \
 287         &sysfs_##name##_rate_bytes,                                     \
 288         &sysfs_##name##_rate_d_term,                                    \
 289         &sysfs_##name##_rate_p_term_inverse,                            \
 290         &sysfs_##name##_rate_debug
 291
 292 #define sysfs_pd_controller_show(name, var)                             \
 293 do {                                                                    \
 294         sysfs_hprint(name##_rate,               (var)->rate.rate);      \
 295         sysfs_print(name##_rate_bytes,          (var)->rate.rate);      \
 296         sysfs_print(name##_rate_d_term,         (var)->d_term);         \
 297         sysfs_print(name##_rate_p_term_inverse, (var)->p_term_inverse); \
 298                                                                         \
 299         if (attr == &sysfs_##name##_rate_debug)                         \
 300                 bch2_pd_controller_debug_to_text(out, var);             \
 301 } while (0)
 302
 303 #define sysfs_pd_controller_store(name, var)                            \
 304 do {                                                                    \
 305         sysfs_strtoul_clamp(name##_rate,                                \
 306                             (var)->rate.rate, 1, UINT_MAX);             \
 307         sysfs_strtoul_clamp(name##_rate_bytes,                          \
 308                             (var)->rate.rate, 1, UINT_MAX);             \
 309         sysfs_strtoul(name##_rate_d_term,       (var)->d_term);         \
 310         sysfs_strtoul_clamp(name##_rate_p_term_inverse,                 \
 311                             (var)->p_term_inverse, 1, INT_MAX);         \
 312 } while (0)
 313
 314 #define container_of_or_null(ptr, type, member)                         \
 315 ({                                                                      \
 316         typeof(ptr) _ptr = ptr;                                         \
 317         _ptr ? container_of(_ptr, type, member) : NULL;                 \
 318 })
 319
 320 /* Does linear interpolation between powers of two */
 321 static inline unsigned fract_exp_two(unsigned x, unsigned fract_bits)
 322 {
 323         unsigned fract = x & ~(~0 << fract_bits);
 324
 325         x >>= fract_bits;
 326         x   = 1 << x;
 327         x  += (x * fract) >> fract_bits;
 328
 329         return x;
 330 }
 331
 332 void bch2_bio_map(struct bio *bio, void *base, size_t);
 333 int bch2_bio_alloc_pages(struct bio *, size_t, gfp_t);
 334
 335 #define closure_bio_submit(bio, cl)                                     \
 336 do {                                                                    \
 337         closure_get(cl);                                                \
 338         submit_bio(bio);                                                \
 339 } while (0)
 340
 341 #define kthread_wait(cond)                                              \
 342 ({                                                                      \
 343         int _ret = 0;                                                   \
 344                                                                         \
 345         while (1) {                                                     \
 346                 set_current_state(TASK_INTERRUPTIBLE);                  \
 347                 if (kthread_should_stop()) {                            \
 348                         _ret = -1;                                      \
 349                         break;                                          \
 350                 }                                                       \
 351                                                                         \
 352                 if (cond)                                               \
 353                         break;                                          \
 354                                                                         \
 355                 schedule();                                             \
 356         }                                                               \
 357         set_current_state(TASK_RUNNING);                                \
 358         _ret;                                                           \
 359 })
 360
 361 #define kthread_wait_freezable(cond)                                    \
 362 ({                                                                      \
 363         int _ret = 0;                                                   \
 364         while (1) {                                                     \
 365                 set_current_state(TASK_INTERRUPTIBLE);                  \
 366                 if (kthread_should_stop()) {                            \
 367                         _ret = -1;                                      \
 368                         break;                                          \
 369                 }                                                       \
 370                                                                         \
 371                 if (cond)                                               \
 372                         break;                                          \
 373                                                                         \
 374                 schedule();                                             \
 375                 try_to_freeze();                                        \
 376         }                                                               \
 377         set_current_state(TASK_RUNNING);                                \
 378         _ret;                                                           \
 379 })
 380
 381 size_t bch2_rand_range(size_t);
 382
 383 void memcpy_to_bio(struct bio *, struct bvec_iter, const void *);
 384 void memcpy_from_bio(void *, struct bio *, struct bvec_iter);
 385
 386 static inline void memcpy_u64s_small(void *dst, const void *src,
 387                                      unsigned u64s)
 388 {
 389         u64 *d = dst;
 390         const u64 *s = src;
 391
 392         while (u64s--)
 393                 *d++ = *s++;
 394 }
 395
 396 static inline void __memcpy_u64s(void *dst, const void *src,
 397                                  unsigned u64s)
 398 {
 399 #ifdef CONFIG_X86_64
 400         long d0, d1, d2;
 401
 402         asm volatile("rep ; movsq"
 403                      : "=&c" (d0), "=&D" (d1), "=&S" (d2)
 404                      : "0" (u64s), "1" (dst), "2" (src)
 405                      : "memory");
 406 #else
 407         u64 *d = dst;
 408         const u64 *s = src;
 409
 410         while (u64s--)
 411                 *d++ = *s++;
 412 #endif
 413 }
 414
 415 static inline void memcpy_u64s(void *dst, const void *src,
 416                                unsigned u64s)
 417 {
 418         EBUG_ON(!(dst >= src + u64s * sizeof(u64) ||
 419                  dst + u64s * sizeof(u64) <= src));
 420
 421         __memcpy_u64s(dst, src, u64s);
 422 }
 423
 424 static inline void __memmove_u64s_down(void *dst, const void *src,
 425                                        unsigned u64s)
 426 {
 427         __memcpy_u64s(dst, src, u64s);
 428 }
 429
 430 static inline void memmove_u64s_down(void *dst, const void *src,
 431                                      unsigned u64s)
 432 {
 433         EBUG_ON(dst > src);
 434
 435         __memmove_u64s_down(dst, src, u64s);
 436 }
 437
 438 static inline void __memmove_u64s_down_small(void *dst, const void *src,
 439                                        unsigned u64s)
 440 {
 441         memcpy_u64s_small(dst, src, u64s);
 442 }
 443
 444 static inline void memmove_u64s_down_small(void *dst, const void *src,
 445                                      unsigned u64s)
 446 {
 447         EBUG_ON(dst > src);
 448
 449         __memmove_u64s_down_small(dst, src, u64s);
 450 }
 451
 452 static inline void __memmove_u64s_up_small(void *_dst, const void *_src,
 453                                            unsigned u64s)
 454 {
 455         u64 *dst = (u64 *) _dst + u64s;
 456         u64 *src = (u64 *) _src + u64s;
 457
 458         while (u64s--)
 459                 *--dst = *--src;
 460 }
 461
 462 static inline void memmove_u64s_up_small(void *dst, const void *src,
 463                                          unsigned u64s)
 464 {
 465         EBUG_ON(dst < src);
 466
 467         __memmove_u64s_up_small(dst, src, u64s);
 468 }
 469
 470 static inline void __memmove_u64s_up(void *_dst, const void *_src,
 471                                      unsigned u64s)
 472 {
 473         u64 *dst = (u64 *) _dst + u64s - 1;
 474         u64 *src = (u64 *) _src + u64s - 1;
 475
 476 #ifdef CONFIG_X86_64
 477         long d0, d1, d2;
 478
 479         asm volatile("std ;\n"
 480                      "rep ; movsq\n"
 481                      "cld ;\n"
 482                      : "=&c" (d0), "=&D" (d1), "=&S" (d2)
 483                      : "0" (u64s), "1" (dst), "2" (src)
 484                      : "memory");
 485 #else
 486         while (u64s--)
 487                 *dst-- = *src--;
 488 #endif
 489 }
 490
 491 static inline void memmove_u64s_up(void *dst, const void *src,
 492                                    unsigned u64s)
 493 {
 494         EBUG_ON(dst < src);
 495
 496         __memmove_u64s_up(dst, src, u64s);
 497 }
 498
 499 static inline void memmove_u64s(void *dst, const void *src,
 500                                 unsigned u64s)
 501 {
 502         if (dst < src)
 503                 __memmove_u64s_down(dst, src, u64s);
 504         else
 505                 __memmove_u64s_up(dst, src, u64s);
 506 }
 507
 508 /* Set the last few bytes up to a u64 boundary given an offset into a buffer. */
 509 static inline void memset_u64s_tail(void *s, int c, unsigned bytes)
 510 {
 511         unsigned rem = round_up(bytes, sizeof(u64)) - bytes;
 512
 513         memset(s + bytes, c, rem);
 514 }
 515
 516 /* just the memmove, doesn't update @_nr */
 517 #define __array_insert_item(_array, _nr, _pos)                          \
 518         memmove(&(_array)[(_pos) + 1],                                  \
 519                 &(_array)[(_pos)],                                      \
 520                 sizeof((_array)[0]) * ((_nr) - (_pos)))
 521
 522 #define array_insert_item(_array, _nr, _pos, _new_item)                 \
 523 do {                                                                    \
 524         __array_insert_item(_array, _nr, _pos);                         \
 525         (_nr)++;                                                        \
 526         (_array)[(_pos)] = (_new_item);                                 \
 527 } while (0)
 528
 529 #define array_remove_items(_array, _nr, _pos, _nr_to_remove)            \
 530 do {                                                                    \
 531         (_nr) -= (_nr_to_remove);                                       \
 532         memmove(&(_array)[(_pos)],                                      \
 533                 &(_array)[(_pos) + (_nr_to_remove)],                    \
 534                 sizeof((_array)[0]) * ((_nr) - (_pos)));                \
 535 } while (0)
 536
 537 #define array_remove_item(_array, _nr, _pos)                            \
 538         array_remove_items(_array, _nr, _pos, 1)
 539
 540 static inline void __move_gap(void *array, size_t element_size,
 541                               size_t nr, size_t size,
 542                               size_t old_gap, size_t new_gap)
 543 {
 544         size_t gap_end = old_gap + size - nr;
 545
 546         if (new_gap < old_gap) {
 547                 size_t move = old_gap - new_gap;
 548
 549                 memmove(array + element_size * (gap_end - move),
 550                         array + element_size * (old_gap - move),
 551                                 element_size * move);
 552         } else if (new_gap > old_gap) {
 553                 size_t move = new_gap - old_gap;
 554
 555                 memmove(array + element_size * old_gap,
 556                         array + element_size * gap_end,
 557                                 element_size * move);
 558         }
 559 }
 560
 561 /* Move the gap in a gap buffer: */
 562 #define move_gap(_d, _new_gap)                                          \
 563 do {                                                                    \
 564         BUG_ON(_new_gap > (_d)->nr);                                    \
 565         BUG_ON((_d)->gap > (_d)->nr);                                   \
 566                                                                         \
 567         __move_gap((_d)->data, sizeof((_d)->data[0]),                   \
 568                    (_d)->nr, (_d)->size, (_d)->gap, _new_gap);          \
 569         (_d)->gap = _new_gap;                                           \
 570 } while (0)
 571
 572 #define bubble_sort(_base, _nr, _cmp)                                   \
 573 do {                                                                    \
 574         ssize_t _i, _last;                                              \
 575         bool _swapped = true;                                           \
 576                                                                         \
 577         for (_last= (ssize_t) (_nr) - 1; _last > 0 && _swapped; --_last) {\
 578                 _swapped = false;                                       \
 579                 for (_i = 0; _i < _last; _i++)                          \
 580                         if (_cmp((_base)[_i], (_base)[_i + 1]) > 0) {   \
 581                                 swap((_base)[_i], (_base)[_i + 1]);     \
 582                                 _swapped = true;                        \
 583                         }                                               \
 584         }                                                               \
 585 } while (0)
 586
 587 #define per_cpu_sum(_p)                                                 \
 588 ({                                                                      \
 589         typeof(*_p) _ret = 0;                                           \
 590                                                                         \
 591         int cpu;                                                        \
 592         for_each_possible_cpu(cpu)                                      \
 593                 _ret += *per_cpu_ptr(_p, cpu);                          \
 594         _ret;                                                           \
 595 })
 596
 597 static inline u64 percpu_u64_get(u64 __percpu *src)
 598 {
 599         return per_cpu_sum(src);
 600 }
 601
 602 static inline void percpu_u64_set(u64 __percpu *dst, u64 src)
 603 {
 604         int cpu;
 605
 606         for_each_possible_cpu(cpu)
 607                 *per_cpu_ptr(dst, cpu) = 0;
 608         this_cpu_write(*dst, src);
 609 }
 610
 611 static inline void acc_u64s(u64 *acc, const u64 *src, unsigned nr)
 612 {
 613         for (unsigned i = 0; i < nr; i++)
 614                 acc[i] += src[i];
 615 }
 616
 617 static inline void acc_u64s_percpu(u64 *acc, const u64 __percpu *src,
 618                                    unsigned nr)
 619 {
 620         int cpu;
 621
 622         for_each_possible_cpu(cpu)
 623                 acc_u64s(acc, per_cpu_ptr(src, cpu), nr);
 624 }
 625
 626 static inline void percpu_memset(void __percpu *p, int c, size_t bytes)
 627 {
 628         int cpu;
 629
 630         for_each_possible_cpu(cpu)
 631                 memset(per_cpu_ptr(p, cpu), c, bytes);
 632 }
 633
 634 u64 *bch2_acc_percpu_u64s(u64 __percpu *, unsigned);
 635
 636 #define cmp_int(l, r)           ((l > r) - (l < r))
 637
 638 static inline int u8_cmp(u8 l, u8 r)
 639 {
 640         return cmp_int(l, r);
 641 }
 642
 643 static inline int cmp_le32(__le32 l, __le32 r)
 644 {
 645         return cmp_int(le32_to_cpu(l), le32_to_cpu(r));
 646 }
 647
 648 #include <linux/uuid.h>
 649
 650 #define QSTR(n) { { { .len = strlen(n) } }, .name = n }
 651
 652 static inline bool qstr_eq(const struct qstr l, const struct qstr r)
 653 {
 654         return l.len == r.len && !memcmp(l.name, r.name, l.len);
 655 }
 656
 657 void bch2_darray_str_exit(darray_str *);
 658 int bch2_split_devs(const char *, darray_str *);
 659
 660 #ifdef __KERNEL__
 661
 662 __must_check
 663 static inline int copy_to_user_errcode(void __user *to, const void *from, unsigned long n)
 664 {
 665         return copy_to_user(to, from, n) ? -EFAULT : 0;
 666 }
 667
 668 __must_check
 669 static inline int copy_from_user_errcode(void *to, const void __user *from, unsigned long n)
 670 {
 671         return copy_from_user(to, from, n) ? -EFAULT : 0;
 672 }
 673
 674 #endif
 675
 676 static inline void mod_bit(long nr, volatile unsigned long *addr, bool v)
 677 {
 678         if (v)
 679                 set_bit(nr, addr);
 680         else
 681                 clear_bit(nr, addr);
 682 }
 683
 684 static inline void __set_bit_le64(size_t bit, __le64 *addr)
 685 {
 686         addr[bit / 64] |= cpu_to_le64(BIT_ULL(bit % 64));
 687 }
 688
 689 static inline void __clear_bit_le64(size_t bit, __le64 *addr)
 690 {
 691         addr[bit / 64] &= ~cpu_to_le64(BIT_ULL(bit % 64));
 692 }
 693
 694 static inline bool test_bit_le64(size_t bit, __le64 *addr)
 695 {
 696         return (addr[bit / 64] & cpu_to_le64(BIT_ULL(bit % 64))) != 0;
 697 }
 698
 699 #endif /* _BCACHEFS_UTIL_H */