xref: /linux/fs/bcachefs/util.h (revision 78c3925c048c752334873f56c3a3d1c9d53e0416)
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/sched/clock.h>
12 #include <linux/llist.h>
13 #include <linux/log2.h>
14 #include <linux/percpu.h>
15 #include <linux/preempt.h>
16 #include <linux/ratelimit.h>
17 #include <linux/slab.h>
18 #include <linux/vmalloc.h>
19 #include <linux/workqueue.h>
20 
21 #include "mean_and_variance.h"
22 
23 #include "darray.h"
24 #include "time_stats.h"
25 
26 struct closure;
27 
28 #ifdef CONFIG_BCACHEFS_DEBUG
29 #define EBUG_ON(cond)		BUG_ON(cond)
30 #else
31 #define EBUG_ON(cond)
32 #endif
33 
34 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
35 #define CPU_BIG_ENDIAN		0
36 #elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
37 #define CPU_BIG_ENDIAN		1
38 #endif
39 
40 /* type hackery */
41 
42 #define type_is_exact(_val, _type)					\
43 	__builtin_types_compatible_p(typeof(_val), _type)
44 
45 #define type_is(_val, _type)						\
46 	(__builtin_types_compatible_p(typeof(_val), _type) ||		\
47 	 __builtin_types_compatible_p(typeof(_val), const _type))
48 
49 /* Userspace doesn't align allocations as nicely as the kernel allocators: */
50 static inline size_t buf_pages(void *p, size_t len)
51 {
52 	return DIV_ROUND_UP(len +
53 			    ((unsigned long) p & (PAGE_SIZE - 1)),
54 			    PAGE_SIZE);
55 }
56 
57 #define HEAP(type)							\
58 struct {								\
59 	size_t size, used;						\
60 	type *data;							\
61 }
62 
63 #define DECLARE_HEAP(type, name) HEAP(type) name
64 
65 #define init_heap(heap, _size, gfp)					\
66 ({									\
67 	(heap)->used = 0;						\
68 	(heap)->size = (_size);						\
69 	(heap)->data = kvmalloc((heap)->size * sizeof((heap)->data[0]),\
70 				 (gfp));				\
71 })
72 
73 #define free_heap(heap)							\
74 do {									\
75 	kvfree((heap)->data);						\
76 	(heap)->data = NULL;						\
77 } while (0)
78 
79 #define heap_set_backpointer(h, i, _fn)					\
80 do {									\
81 	void (*fn)(typeof(h), size_t) = _fn;				\
82 	if (fn)								\
83 		fn(h, i);						\
84 } while (0)
85 
86 #define heap_swap(h, i, j, set_backpointer)				\
87 do {									\
88 	swap((h)->data[i], (h)->data[j]);				\
89 	heap_set_backpointer(h, i, set_backpointer);			\
90 	heap_set_backpointer(h, j, set_backpointer);			\
91 } while (0)
92 
93 #define heap_peek(h)							\
94 ({									\
95 	EBUG_ON(!(h)->used);						\
96 	(h)->data[0];							\
97 })
98 
99 #define heap_full(h)	((h)->used == (h)->size)
100 
101 #define heap_sift_down(h, i, cmp, set_backpointer)			\
102 do {									\
103 	size_t _c, _j = i;						\
104 									\
105 	for (; _j * 2 + 1 < (h)->used; _j = _c) {			\
106 		_c = _j * 2 + 1;					\
107 		if (_c + 1 < (h)->used &&				\
108 		    cmp(h, (h)->data[_c], (h)->data[_c + 1]) >= 0)	\
109 			_c++;						\
110 									\
111 		if (cmp(h, (h)->data[_c], (h)->data[_j]) >= 0)		\
112 			break;						\
113 		heap_swap(h, _c, _j, set_backpointer);			\
114 	}								\
115 } while (0)
116 
117 #define heap_sift_up(h, i, cmp, set_backpointer)			\
118 do {									\
119 	while (i) {							\
120 		size_t p = (i - 1) / 2;					\
121 		if (cmp(h, (h)->data[i], (h)->data[p]) >= 0)		\
122 			break;						\
123 		heap_swap(h, i, p, set_backpointer);			\
124 		i = p;							\
125 	}								\
126 } while (0)
127 
128 #define __heap_add(h, d, cmp, set_backpointer)				\
129 ({									\
130 	size_t _i = (h)->used++;					\
131 	(h)->data[_i] = d;						\
132 	heap_set_backpointer(h, _i, set_backpointer);			\
133 									\
134 	heap_sift_up(h, _i, cmp, set_backpointer);			\
135 	_i;								\
136 })
137 
138 #define heap_add(h, d, cmp, set_backpointer)				\
139 ({									\
140 	bool _r = !heap_full(h);					\
141 	if (_r)								\
142 		__heap_add(h, d, cmp, set_backpointer);			\
143 	_r;								\
144 })
145 
146 #define heap_add_or_replace(h, new, cmp, set_backpointer)		\
147 do {									\
148 	if (!heap_add(h, new, cmp, set_backpointer) &&			\
149 	    cmp(h, new, heap_peek(h)) >= 0) {				\
150 		(h)->data[0] = new;					\
151 		heap_set_backpointer(h, 0, set_backpointer);		\
152 		heap_sift_down(h, 0, cmp, set_backpointer);		\
153 	}								\
154 } while (0)
155 
156 #define heap_del(h, i, cmp, set_backpointer)				\
157 do {									\
158 	size_t _i = (i);						\
159 									\
160 	BUG_ON(_i >= (h)->used);					\
161 	(h)->used--;							\
162 	if ((_i) < (h)->used) {						\
163 		heap_swap(h, _i, (h)->used, set_backpointer);		\
164 		heap_sift_up(h, _i, cmp, set_backpointer);		\
165 		heap_sift_down(h, _i, cmp, set_backpointer);		\
166 	}								\
167 } while (0)
168 
169 #define heap_pop(h, d, cmp, set_backpointer)				\
170 ({									\
171 	bool _r = (h)->used;						\
172 	if (_r) {							\
173 		(d) = (h)->data[0];					\
174 		heap_del(h, 0, cmp, set_backpointer);			\
175 	}								\
176 	_r;								\
177 })
178 
179 #define heap_resort(heap, cmp, set_backpointer)				\
180 do {									\
181 	ssize_t _i;							\
182 	for (_i = (ssize_t) (heap)->used / 2 -  1; _i >= 0; --_i)	\
183 		heap_sift_down(heap, _i, cmp, set_backpointer);		\
184 } while (0)
185 
186 #define ANYSINT_MAX(t)							\
187 	((((t) 1 << (sizeof(t) * 8 - 2)) - (t) 1) * (t) 2 + (t) 1)
188 
189 #include "printbuf.h"
190 
191 #define prt_vprintf(_out, ...)		bch2_prt_vprintf(_out, __VA_ARGS__)
192 #define prt_printf(_out, ...)		bch2_prt_printf(_out, __VA_ARGS__)
193 #define printbuf_str(_buf)		bch2_printbuf_str(_buf)
194 #define printbuf_exit(_buf)		bch2_printbuf_exit(_buf)
195 
196 #define printbuf_tabstops_reset(_buf)	bch2_printbuf_tabstops_reset(_buf)
197 #define printbuf_tabstop_pop(_buf)	bch2_printbuf_tabstop_pop(_buf)
198 #define printbuf_tabstop_push(_buf, _n)	bch2_printbuf_tabstop_push(_buf, _n)
199 
200 #define printbuf_indent_add(_out, _n)	bch2_printbuf_indent_add(_out, _n)
201 #define printbuf_indent_sub(_out, _n)	bch2_printbuf_indent_sub(_out, _n)
202 
203 #define prt_newline(_out)		bch2_prt_newline(_out)
204 #define prt_tab(_out)			bch2_prt_tab(_out)
205 #define prt_tab_rjust(_out)		bch2_prt_tab_rjust(_out)
206 
207 #define prt_bytes_indented(...)		bch2_prt_bytes_indented(__VA_ARGS__)
208 #define prt_u64(_out, _v)		prt_printf(_out, "%llu", (u64) (_v))
209 #define prt_human_readable_u64(...)	bch2_prt_human_readable_u64(__VA_ARGS__)
210 #define prt_human_readable_s64(...)	bch2_prt_human_readable_s64(__VA_ARGS__)
211 #define prt_units_u64(...)		bch2_prt_units_u64(__VA_ARGS__)
212 #define prt_units_s64(...)		bch2_prt_units_s64(__VA_ARGS__)
213 #define prt_string_option(...)		bch2_prt_string_option(__VA_ARGS__)
214 #define prt_bitflags(...)		bch2_prt_bitflags(__VA_ARGS__)
215 #define prt_bitflags_vector(...)	bch2_prt_bitflags_vector(__VA_ARGS__)
216 
217 void bch2_pr_time_units(struct printbuf *, u64);
218 void bch2_prt_datetime(struct printbuf *, time64_t);
219 
220 #ifdef __KERNEL__
221 static inline void uuid_unparse_lower(u8 *uuid, char *out)
222 {
223 	sprintf(out, "%pUb", uuid);
224 }
225 #else
226 #include <uuid/uuid.h>
227 #endif
228 
229 static inline void pr_uuid(struct printbuf *out, u8 *uuid)
230 {
231 	char uuid_str[40];
232 
233 	uuid_unparse_lower(uuid, uuid_str);
234 	prt_printf(out, "%s", uuid_str);
235 }
236 
237 int bch2_strtoint_h(const char *, int *);
238 int bch2_strtouint_h(const char *, unsigned int *);
239 int bch2_strtoll_h(const char *, long long *);
240 int bch2_strtoull_h(const char *, unsigned long long *);
241 int bch2_strtou64_h(const char *, u64 *);
242 
243 static inline int bch2_strtol_h(const char *cp, long *res)
244 {
245 #if BITS_PER_LONG == 32
246 	return bch2_strtoint_h(cp, (int *) res);
247 #else
248 	return bch2_strtoll_h(cp, (long long *) res);
249 #endif
250 }
251 
252 static inline int bch2_strtoul_h(const char *cp, long *res)
253 {
254 #if BITS_PER_LONG == 32
255 	return bch2_strtouint_h(cp, (unsigned int *) res);
256 #else
257 	return bch2_strtoull_h(cp, (unsigned long long *) res);
258 #endif
259 }
260 
261 #define strtoi_h(cp, res)						\
262 	( type_is(*res, int)		? bch2_strtoint_h(cp, (void *) res)\
263 	: type_is(*res, long)		? bch2_strtol_h(cp, (void *) res)\
264 	: type_is(*res, long long)	? bch2_strtoll_h(cp, (void *) res)\
265 	: type_is(*res, unsigned)	? bch2_strtouint_h(cp, (void *) res)\
266 	: type_is(*res, unsigned long)	? bch2_strtoul_h(cp, (void *) res)\
267 	: type_is(*res, unsigned long long) ? bch2_strtoull_h(cp, (void *) res)\
268 	: -EINVAL)
269 
270 #define strtoul_safe(cp, var)						\
271 ({									\
272 	unsigned long _v;						\
273 	int _r = kstrtoul(cp, 10, &_v);					\
274 	if (!_r)							\
275 		var = _v;						\
276 	_r;								\
277 })
278 
279 #define strtoul_safe_clamp(cp, var, min, max)				\
280 ({									\
281 	unsigned long _v;						\
282 	int _r = kstrtoul(cp, 10, &_v);					\
283 	if (!_r)							\
284 		var = clamp_t(typeof(var), _v, min, max);		\
285 	_r;								\
286 })
287 
288 #define strtoul_safe_restrict(cp, var, min, max)			\
289 ({									\
290 	unsigned long _v;						\
291 	int _r = kstrtoul(cp, 10, &_v);					\
292 	if (!_r && _v >= min && _v <= max)				\
293 		var = _v;						\
294 	else								\
295 		_r = -EINVAL;						\
296 	_r;								\
297 })
298 
299 #define snprint(out, var)						\
300 	prt_printf(out,							\
301 		   type_is(var, int)		? "%i\n"		\
302 		 : type_is(var, unsigned)	? "%u\n"		\
303 		 : type_is(var, long)		? "%li\n"		\
304 		 : type_is(var, unsigned long)	? "%lu\n"		\
305 		 : type_is(var, s64)		? "%lli\n"		\
306 		 : type_is(var, u64)		? "%llu\n"		\
307 		 : type_is(var, char *)		? "%s\n"		\
308 		 : "%i\n", var)
309 
310 bool bch2_is_zero(const void *, size_t);
311 
312 u64 bch2_read_flag_list(char *, const char * const[]);
313 
314 void bch2_prt_u64_base2_nbits(struct printbuf *, u64, unsigned);
315 void bch2_prt_u64_base2(struct printbuf *, u64);
316 
317 void bch2_print_string_as_lines(const char *prefix, const char *lines);
318 
319 typedef DARRAY(unsigned long) bch_stacktrace;
320 int bch2_save_backtrace(bch_stacktrace *stack, struct task_struct *, unsigned, gfp_t);
321 void bch2_prt_backtrace(struct printbuf *, bch_stacktrace *);
322 int bch2_prt_task_backtrace(struct printbuf *, struct task_struct *, unsigned, gfp_t);
323 
324 static inline void prt_bdevname(struct printbuf *out, struct block_device *bdev)
325 {
326 #ifdef __KERNEL__
327 	prt_printf(out, "%pg", bdev);
328 #else
329 	prt_str(out, bdev->name);
330 #endif
331 }
332 
333 void bch2_time_stats_to_text(struct printbuf *, struct bch2_time_stats *);
334 
335 #define ewma_add(ewma, val, weight)					\
336 ({									\
337 	typeof(ewma) _ewma = (ewma);					\
338 	typeof(weight) _weight = (weight);				\
339 									\
340 	(((_ewma << _weight) - _ewma) + (val)) >> _weight;		\
341 })
342 
343 struct bch_ratelimit {
344 	/* Next time we want to do some work, in nanoseconds */
345 	u64			next;
346 
347 	/*
348 	 * Rate at which we want to do work, in units per nanosecond
349 	 * The units here correspond to the units passed to
350 	 * bch2_ratelimit_increment()
351 	 */
352 	unsigned		rate;
353 };
354 
355 static inline void bch2_ratelimit_reset(struct bch_ratelimit *d)
356 {
357 	d->next = local_clock();
358 }
359 
360 u64 bch2_ratelimit_delay(struct bch_ratelimit *);
361 void bch2_ratelimit_increment(struct bch_ratelimit *, u64);
362 
363 struct bch_pd_controller {
364 	struct bch_ratelimit	rate;
365 	unsigned long		last_update;
366 
367 	s64			last_actual;
368 	s64			smoothed_derivative;
369 
370 	unsigned		p_term_inverse;
371 	unsigned		d_smooth;
372 	unsigned		d_term;
373 
374 	/* for exporting to sysfs (no effect on behavior) */
375 	s64			last_derivative;
376 	s64			last_proportional;
377 	s64			last_change;
378 	s64			last_target;
379 
380 	/*
381 	 * If true, the rate will not increase if bch2_ratelimit_delay()
382 	 * is not being called often enough.
383 	 */
384 	bool			backpressure;
385 };
386 
387 void bch2_pd_controller_update(struct bch_pd_controller *, s64, s64, int);
388 void bch2_pd_controller_init(struct bch_pd_controller *);
389 void bch2_pd_controller_debug_to_text(struct printbuf *, struct bch_pd_controller *);
390 
391 #define sysfs_pd_controller_attribute(name)				\
392 	rw_attribute(name##_rate);					\
393 	rw_attribute(name##_rate_bytes);				\
394 	rw_attribute(name##_rate_d_term);				\
395 	rw_attribute(name##_rate_p_term_inverse);			\
396 	read_attribute(name##_rate_debug)
397 
398 #define sysfs_pd_controller_files(name)					\
399 	&sysfs_##name##_rate,						\
400 	&sysfs_##name##_rate_bytes,					\
401 	&sysfs_##name##_rate_d_term,					\
402 	&sysfs_##name##_rate_p_term_inverse,				\
403 	&sysfs_##name##_rate_debug
404 
405 #define sysfs_pd_controller_show(name, var)				\
406 do {									\
407 	sysfs_hprint(name##_rate,		(var)->rate.rate);	\
408 	sysfs_print(name##_rate_bytes,		(var)->rate.rate);	\
409 	sysfs_print(name##_rate_d_term,		(var)->d_term);		\
410 	sysfs_print(name##_rate_p_term_inverse,	(var)->p_term_inverse);	\
411 									\
412 	if (attr == &sysfs_##name##_rate_debug)				\
413 		bch2_pd_controller_debug_to_text(out, var);		\
414 } while (0)
415 
416 #define sysfs_pd_controller_store(name, var)				\
417 do {									\
418 	sysfs_strtoul_clamp(name##_rate,				\
419 			    (var)->rate.rate, 1, UINT_MAX);		\
420 	sysfs_strtoul_clamp(name##_rate_bytes,				\
421 			    (var)->rate.rate, 1, UINT_MAX);		\
422 	sysfs_strtoul(name##_rate_d_term,	(var)->d_term);		\
423 	sysfs_strtoul_clamp(name##_rate_p_term_inverse,			\
424 			    (var)->p_term_inverse, 1, INT_MAX);		\
425 } while (0)
426 
427 #define container_of_or_null(ptr, type, member)				\
428 ({									\
429 	typeof(ptr) _ptr = ptr;						\
430 	_ptr ? container_of(_ptr, type, member) : NULL;			\
431 })
432 
433 /* Does linear interpolation between powers of two */
434 static inline unsigned fract_exp_two(unsigned x, unsigned fract_bits)
435 {
436 	unsigned fract = x & ~(~0 << fract_bits);
437 
438 	x >>= fract_bits;
439 	x   = 1 << x;
440 	x  += (x * fract) >> fract_bits;
441 
442 	return x;
443 }
444 
445 void bch2_bio_map(struct bio *bio, void *base, size_t);
446 int bch2_bio_alloc_pages(struct bio *, size_t, gfp_t);
447 
448 static inline sector_t bdev_sectors(struct block_device *bdev)
449 {
450 	return bdev->bd_inode->i_size >> 9;
451 }
452 
453 #define closure_bio_submit(bio, cl)					\
454 do {									\
455 	closure_get(cl);						\
456 	submit_bio(bio);						\
457 } while (0)
458 
459 #define kthread_wait(cond)						\
460 ({									\
461 	int _ret = 0;							\
462 									\
463 	while (1) {							\
464 		set_current_state(TASK_INTERRUPTIBLE);			\
465 		if (kthread_should_stop()) {				\
466 			_ret = -1;					\
467 			break;						\
468 		}							\
469 									\
470 		if (cond)						\
471 			break;						\
472 									\
473 		schedule();						\
474 	}								\
475 	set_current_state(TASK_RUNNING);				\
476 	_ret;								\
477 })
478 
479 #define kthread_wait_freezable(cond)					\
480 ({									\
481 	int _ret = 0;							\
482 	while (1) {							\
483 		set_current_state(TASK_INTERRUPTIBLE);			\
484 		if (kthread_should_stop()) {				\
485 			_ret = -1;					\
486 			break;						\
487 		}							\
488 									\
489 		if (cond)						\
490 			break;						\
491 									\
492 		schedule();						\
493 		try_to_freeze();					\
494 	}								\
495 	set_current_state(TASK_RUNNING);				\
496 	_ret;								\
497 })
498 
499 size_t bch2_rand_range(size_t);
500 
501 void memcpy_to_bio(struct bio *, struct bvec_iter, const void *);
502 void memcpy_from_bio(void *, struct bio *, struct bvec_iter);
503 
504 static inline void memcpy_u64s_small(void *dst, const void *src,
505 				     unsigned u64s)
506 {
507 	u64 *d = dst;
508 	const u64 *s = src;
509 
510 	while (u64s--)
511 		*d++ = *s++;
512 }
513 
514 static inline void __memcpy_u64s(void *dst, const void *src,
515 				 unsigned u64s)
516 {
517 #ifdef CONFIG_X86_64
518 	long d0, d1, d2;
519 
520 	asm volatile("rep ; movsq"
521 		     : "=&c" (d0), "=&D" (d1), "=&S" (d2)
522 		     : "0" (u64s), "1" (dst), "2" (src)
523 		     : "memory");
524 #else
525 	u64 *d = dst;
526 	const u64 *s = src;
527 
528 	while (u64s--)
529 		*d++ = *s++;
530 #endif
531 }
532 
533 static inline void memcpy_u64s(void *dst, const void *src,
534 			       unsigned u64s)
535 {
536 	EBUG_ON(!(dst >= src + u64s * sizeof(u64) ||
537 		 dst + u64s * sizeof(u64) <= src));
538 
539 	__memcpy_u64s(dst, src, u64s);
540 }
541 
542 static inline void __memmove_u64s_down(void *dst, const void *src,
543 				       unsigned u64s)
544 {
545 	__memcpy_u64s(dst, src, u64s);
546 }
547 
548 static inline void memmove_u64s_down(void *dst, const void *src,
549 				     unsigned u64s)
550 {
551 	EBUG_ON(dst > src);
552 
553 	__memmove_u64s_down(dst, src, u64s);
554 }
555 
556 static inline void __memmove_u64s_down_small(void *dst, const void *src,
557 				       unsigned u64s)
558 {
559 	memcpy_u64s_small(dst, src, u64s);
560 }
561 
562 static inline void memmove_u64s_down_small(void *dst, const void *src,
563 				     unsigned u64s)
564 {
565 	EBUG_ON(dst > src);
566 
567 	__memmove_u64s_down_small(dst, src, u64s);
568 }
569 
570 static inline void __memmove_u64s_up_small(void *_dst, const void *_src,
571 					   unsigned u64s)
572 {
573 	u64 *dst = (u64 *) _dst + u64s;
574 	u64 *src = (u64 *) _src + u64s;
575 
576 	while (u64s--)
577 		*--dst = *--src;
578 }
579 
580 static inline void memmove_u64s_up_small(void *dst, const void *src,
581 					 unsigned u64s)
582 {
583 	EBUG_ON(dst < src);
584 
585 	__memmove_u64s_up_small(dst, src, u64s);
586 }
587 
588 static inline void __memmove_u64s_up(void *_dst, const void *_src,
589 				     unsigned u64s)
590 {
591 	u64 *dst = (u64 *) _dst + u64s - 1;
592 	u64 *src = (u64 *) _src + u64s - 1;
593 
594 #ifdef CONFIG_X86_64
595 	long d0, d1, d2;
596 
597 	asm volatile("std ;\n"
598 		     "rep ; movsq\n"
599 		     "cld ;\n"
600 		     : "=&c" (d0), "=&D" (d1), "=&S" (d2)
601 		     : "0" (u64s), "1" (dst), "2" (src)
602 		     : "memory");
603 #else
604 	while (u64s--)
605 		*dst-- = *src--;
606 #endif
607 }
608 
609 static inline void memmove_u64s_up(void *dst, const void *src,
610 				   unsigned u64s)
611 {
612 	EBUG_ON(dst < src);
613 
614 	__memmove_u64s_up(dst, src, u64s);
615 }
616 
617 static inline void memmove_u64s(void *dst, const void *src,
618 				unsigned u64s)
619 {
620 	if (dst < src)
621 		__memmove_u64s_down(dst, src, u64s);
622 	else
623 		__memmove_u64s_up(dst, src, u64s);
624 }
625 
626 /* Set the last few bytes up to a u64 boundary given an offset into a buffer. */
627 static inline void memset_u64s_tail(void *s, int c, unsigned bytes)
628 {
629 	unsigned rem = round_up(bytes, sizeof(u64)) - bytes;
630 
631 	memset(s + bytes, c, rem);
632 }
633 
634 void sort_cmp_size(void *base, size_t num, size_t size,
635 	  int (*cmp_func)(const void *, const void *, size_t),
636 	  void (*swap_func)(void *, void *, size_t));
637 
638 /* just the memmove, doesn't update @_nr */
639 #define __array_insert_item(_array, _nr, _pos)				\
640 	memmove(&(_array)[(_pos) + 1],					\
641 		&(_array)[(_pos)],					\
642 		sizeof((_array)[0]) * ((_nr) - (_pos)))
643 
644 #define array_insert_item(_array, _nr, _pos, _new_item)			\
645 do {									\
646 	__array_insert_item(_array, _nr, _pos);				\
647 	(_nr)++;							\
648 	(_array)[(_pos)] = (_new_item);					\
649 } while (0)
650 
651 #define array_remove_items(_array, _nr, _pos, _nr_to_remove)		\
652 do {									\
653 	(_nr) -= (_nr_to_remove);					\
654 	memmove(&(_array)[(_pos)],					\
655 		&(_array)[(_pos) + (_nr_to_remove)],			\
656 		sizeof((_array)[0]) * ((_nr) - (_pos)));		\
657 } while (0)
658 
659 #define array_remove_item(_array, _nr, _pos)				\
660 	array_remove_items(_array, _nr, _pos, 1)
661 
662 static inline void __move_gap(void *array, size_t element_size,
663 			      size_t nr, size_t size,
664 			      size_t old_gap, size_t new_gap)
665 {
666 	size_t gap_end = old_gap + size - nr;
667 
668 	if (new_gap < old_gap) {
669 		size_t move = old_gap - new_gap;
670 
671 		memmove(array + element_size * (gap_end - move),
672 			array + element_size * (old_gap - move),
673 				element_size * move);
674 	} else if (new_gap > old_gap) {
675 		size_t move = new_gap - old_gap;
676 
677 		memmove(array + element_size * old_gap,
678 			array + element_size * gap_end,
679 				element_size * move);
680 	}
681 }
682 
683 /* Move the gap in a gap buffer: */
684 #define move_gap(_d, _new_gap)						\
685 do {									\
686 	__move_gap((_d)->data, sizeof((_d)->data[0]),			\
687 		   (_d)->nr, (_d)->size, (_d)->gap, _new_gap);		\
688 	(_d)->gap = _new_gap;						\
689 } while (0)
690 
691 #define bubble_sort(_base, _nr, _cmp)					\
692 do {									\
693 	ssize_t _i, _last;						\
694 	bool _swapped = true;						\
695 									\
696 	for (_last= (ssize_t) (_nr) - 1; _last > 0 && _swapped; --_last) {\
697 		_swapped = false;					\
698 		for (_i = 0; _i < _last; _i++)				\
699 			if (_cmp((_base)[_i], (_base)[_i + 1]) > 0) {	\
700 				swap((_base)[_i], (_base)[_i + 1]);	\
701 				_swapped = true;			\
702 			}						\
703 	}								\
704 } while (0)
705 
706 static inline u64 percpu_u64_get(u64 __percpu *src)
707 {
708 	u64 ret = 0;
709 	int cpu;
710 
711 	for_each_possible_cpu(cpu)
712 		ret += *per_cpu_ptr(src, cpu);
713 	return ret;
714 }
715 
716 static inline void percpu_u64_set(u64 __percpu *dst, u64 src)
717 {
718 	int cpu;
719 
720 	for_each_possible_cpu(cpu)
721 		*per_cpu_ptr(dst, cpu) = 0;
722 	this_cpu_write(*dst, src);
723 }
724 
725 static inline void acc_u64s(u64 *acc, const u64 *src, unsigned nr)
726 {
727 	unsigned i;
728 
729 	for (i = 0; i < nr; i++)
730 		acc[i] += src[i];
731 }
732 
733 static inline void acc_u64s_percpu(u64 *acc, const u64 __percpu *src,
734 				   unsigned nr)
735 {
736 	int cpu;
737 
738 	for_each_possible_cpu(cpu)
739 		acc_u64s(acc, per_cpu_ptr(src, cpu), nr);
740 }
741 
742 static inline void percpu_memset(void __percpu *p, int c, size_t bytes)
743 {
744 	int cpu;
745 
746 	for_each_possible_cpu(cpu)
747 		memset(per_cpu_ptr(p, cpu), c, bytes);
748 }
749 
750 u64 *bch2_acc_percpu_u64s(u64 __percpu *, unsigned);
751 
752 #define cmp_int(l, r)		((l > r) - (l < r))
753 
754 static inline int u8_cmp(u8 l, u8 r)
755 {
756 	return cmp_int(l, r);
757 }
758 
759 static inline int cmp_le32(__le32 l, __le32 r)
760 {
761 	return cmp_int(le32_to_cpu(l), le32_to_cpu(r));
762 }
763 
764 #include <linux/uuid.h>
765 
766 #define QSTR(n) { { { .len = strlen(n) } }, .name = n }
767 
768 static inline bool qstr_eq(const struct qstr l, const struct qstr r)
769 {
770 	return l.len == r.len && !memcmp(l.name, r.name, l.len);
771 }
772 
773 void bch2_darray_str_exit(darray_str *);
774 int bch2_split_devs(const char *, darray_str *);
775 
776 #ifdef __KERNEL__
777 
778 __must_check
779 static inline int copy_to_user_errcode(void __user *to, const void *from, unsigned long n)
780 {
781 	return copy_to_user(to, from, n) ? -EFAULT : 0;
782 }
783 
784 __must_check
785 static inline int copy_from_user_errcode(void *to, const void __user *from, unsigned long n)
786 {
787 	return copy_from_user(to, from, n) ? -EFAULT : 0;
788 }
789 
790 #endif
791 
792 static inline void __set_bit_le64(size_t bit, __le64 *addr)
793 {
794 	addr[bit / 64] |= cpu_to_le64(BIT_ULL(bit % 64));
795 }
796 
797 #endif /* _BCACHEFS_UTIL_H */
798