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(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 : "" (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 : "" (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 */
700
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