xref: /linux/drivers/md/bcache/util.h (revision b77e0ce62d63a761ffb7f7245a215a49f5921c2f)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 
3 #ifndef _BCACHE_UTIL_H
4 #define _BCACHE_UTIL_H
5 
6 #include <linux/blkdev.h>
7 #include <linux/errno.h>
8 #include <linux/kernel.h>
9 #include <linux/sched/clock.h>
10 #include <linux/llist.h>
11 #include <linux/ratelimit.h>
12 #include <linux/vmalloc.h>
13 #include <linux/workqueue.h>
14 #include <linux/crc64.h>
15 
16 #include "closure.h"
17 
18 #define PAGE_SECTORS		(PAGE_SIZE / 512)
19 
20 struct closure;
21 
22 #ifdef CONFIG_BCACHE_DEBUG
23 
24 #define EBUG_ON(cond)			BUG_ON(cond)
25 #define atomic_dec_bug(v)	BUG_ON(atomic_dec_return(v) < 0)
26 #define atomic_inc_bug(v, i)	BUG_ON(atomic_inc_return(v) <= i)
27 
28 #else /* DEBUG */
29 
30 #define EBUG_ON(cond)			do { if (cond); } while (0)
31 #define atomic_dec_bug(v)	atomic_dec(v)
32 #define atomic_inc_bug(v, i)	atomic_inc(v)
33 
34 #endif
35 
36 #define DECLARE_HEAP(type, name)					\
37 	struct {							\
38 		size_t size, used;					\
39 		type *data;						\
40 	} name
41 
42 #define init_heap(heap, _size, gfp)					\
43 ({									\
44 	size_t _bytes;							\
45 	(heap)->used = 0;						\
46 	(heap)->size = (_size);						\
47 	_bytes = (heap)->size * sizeof(*(heap)->data);			\
48 	(heap)->data = kvmalloc(_bytes, (gfp) & GFP_KERNEL);		\
49 	(heap)->data;							\
50 })
51 
52 #define free_heap(heap)							\
53 do {									\
54 	kvfree((heap)->data);						\
55 	(heap)->data = NULL;						\
56 } while (0)
57 
58 #define heap_swap(h, i, j)	swap((h)->data[i], (h)->data[j])
59 
60 #define heap_sift(h, i, cmp)						\
61 do {									\
62 	size_t _r, _j = i;						\
63 									\
64 	for (; _j * 2 + 1 < (h)->used; _j = _r) {			\
65 		_r = _j * 2 + 1;					\
66 		if (_r + 1 < (h)->used &&				\
67 		    cmp((h)->data[_r], (h)->data[_r + 1]))		\
68 			_r++;						\
69 									\
70 		if (cmp((h)->data[_r], (h)->data[_j]))			\
71 			break;						\
72 		heap_swap(h, _r, _j);					\
73 	}								\
74 } while (0)
75 
76 #define heap_sift_down(h, i, cmp)					\
77 do {									\
78 	while (i) {							\
79 		size_t p = (i - 1) / 2;					\
80 		if (cmp((h)->data[i], (h)->data[p]))			\
81 			break;						\
82 		heap_swap(h, i, p);					\
83 		i = p;							\
84 	}								\
85 } while (0)
86 
87 #define heap_add(h, d, cmp)						\
88 ({									\
89 	bool _r = !heap_full(h);					\
90 	if (_r) {							\
91 		size_t _i = (h)->used++;				\
92 		(h)->data[_i] = d;					\
93 									\
94 		heap_sift_down(h, _i, cmp);				\
95 		heap_sift(h, _i, cmp);					\
96 	}								\
97 	_r;								\
98 })
99 
100 #define heap_pop(h, d, cmp)						\
101 ({									\
102 	bool _r = (h)->used;						\
103 	if (_r) {							\
104 		(d) = (h)->data[0];					\
105 		(h)->used--;						\
106 		heap_swap(h, 0, (h)->used);				\
107 		heap_sift(h, 0, cmp);					\
108 	}								\
109 	_r;								\
110 })
111 
112 #define heap_peek(h)	((h)->used ? (h)->data[0] : NULL)
113 
114 #define heap_full(h)	((h)->used == (h)->size)
115 
116 #define DECLARE_FIFO(type, name)					\
117 	struct {							\
118 		size_t front, back, size, mask;				\
119 		type *data;						\
120 	} name
121 
122 #define fifo_for_each(c, fifo, iter)					\
123 	for (iter = (fifo)->front;					\
124 	     c = (fifo)->data[iter], iter != (fifo)->back;		\
125 	     iter = (iter + 1) & (fifo)->mask)
126 
127 #define __init_fifo(fifo, gfp)						\
128 ({									\
129 	size_t _allocated_size, _bytes;					\
130 	BUG_ON(!(fifo)->size);						\
131 									\
132 	_allocated_size = roundup_pow_of_two((fifo)->size + 1);		\
133 	_bytes = _allocated_size * sizeof(*(fifo)->data);		\
134 									\
135 	(fifo)->mask = _allocated_size - 1;				\
136 	(fifo)->front = (fifo)->back = 0;				\
137 									\
138 	(fifo)->data = kvmalloc(_bytes, (gfp) & GFP_KERNEL);		\
139 	(fifo)->data;							\
140 })
141 
142 #define init_fifo_exact(fifo, _size, gfp)				\
143 ({									\
144 	(fifo)->size = (_size);						\
145 	__init_fifo(fifo, gfp);						\
146 })
147 
148 #define init_fifo(fifo, _size, gfp)					\
149 ({									\
150 	(fifo)->size = (_size);						\
151 	if ((fifo)->size > 4)						\
152 		(fifo)->size = roundup_pow_of_two((fifo)->size) - 1;	\
153 	__init_fifo(fifo, gfp);						\
154 })
155 
156 #define free_fifo(fifo)							\
157 do {									\
158 	kvfree((fifo)->data);						\
159 	(fifo)->data = NULL;						\
160 } while (0)
161 
162 #define fifo_used(fifo)		(((fifo)->back - (fifo)->front) & (fifo)->mask)
163 #define fifo_free(fifo)		((fifo)->size - fifo_used(fifo))
164 
165 #define fifo_empty(fifo)	(!fifo_used(fifo))
166 #define fifo_full(fifo)		(!fifo_free(fifo))
167 
168 #define fifo_front(fifo)	((fifo)->data[(fifo)->front])
169 #define fifo_back(fifo)							\
170 	((fifo)->data[((fifo)->back - 1) & (fifo)->mask])
171 
172 #define fifo_idx(fifo, p)	(((p) - &fifo_front(fifo)) & (fifo)->mask)
173 
174 #define fifo_push_back(fifo, i)						\
175 ({									\
176 	bool _r = !fifo_full((fifo));					\
177 	if (_r) {							\
178 		(fifo)->data[(fifo)->back++] = (i);			\
179 		(fifo)->back &= (fifo)->mask;				\
180 	}								\
181 	_r;								\
182 })
183 
184 #define fifo_pop_front(fifo, i)						\
185 ({									\
186 	bool _r = !fifo_empty((fifo));					\
187 	if (_r) {							\
188 		(i) = (fifo)->data[(fifo)->front++];			\
189 		(fifo)->front &= (fifo)->mask;				\
190 	}								\
191 	_r;								\
192 })
193 
194 #define fifo_push_front(fifo, i)					\
195 ({									\
196 	bool _r = !fifo_full((fifo));					\
197 	if (_r) {							\
198 		--(fifo)->front;					\
199 		(fifo)->front &= (fifo)->mask;				\
200 		(fifo)->data[(fifo)->front] = (i);			\
201 	}								\
202 	_r;								\
203 })
204 
205 #define fifo_pop_back(fifo, i)						\
206 ({									\
207 	bool _r = !fifo_empty((fifo));					\
208 	if (_r) {							\
209 		--(fifo)->back;						\
210 		(fifo)->back &= (fifo)->mask;				\
211 		(i) = (fifo)->data[(fifo)->back]			\
212 	}								\
213 	_r;								\
214 })
215 
216 #define fifo_push(fifo, i)	fifo_push_back(fifo, (i))
217 #define fifo_pop(fifo, i)	fifo_pop_front(fifo, (i))
218 
219 #define fifo_swap(l, r)							\
220 do {									\
221 	swap((l)->front, (r)->front);					\
222 	swap((l)->back, (r)->back);					\
223 	swap((l)->size, (r)->size);					\
224 	swap((l)->mask, (r)->mask);					\
225 	swap((l)->data, (r)->data);					\
226 } while (0)
227 
228 #define fifo_move(dest, src)						\
229 do {									\
230 	typeof(*((dest)->data)) _t;					\
231 	while (!fifo_full(dest) &&					\
232 	       fifo_pop(src, _t))					\
233 		fifo_push(dest, _t);					\
234 } while (0)
235 
236 /*
237  * Simple array based allocator - preallocates a number of elements and you can
238  * never allocate more than that, also has no locking.
239  *
240  * Handy because if you know you only need a fixed number of elements you don't
241  * have to worry about memory allocation failure, and sometimes a mempool isn't
242  * what you want.
243  *
244  * We treat the free elements as entries in a singly linked list, and the
245  * freelist as a stack - allocating and freeing push and pop off the freelist.
246  */
247 
248 #define DECLARE_ARRAY_ALLOCATOR(type, name, size)			\
249 	struct {							\
250 		type	*freelist;					\
251 		type	data[size];					\
252 	} name
253 
254 #define array_alloc(array)						\
255 ({									\
256 	typeof((array)->freelist) _ret = (array)->freelist;		\
257 									\
258 	if (_ret)							\
259 		(array)->freelist = *((typeof((array)->freelist) *) _ret);\
260 									\
261 	_ret;								\
262 })
263 
264 #define array_free(array, ptr)						\
265 do {									\
266 	typeof((array)->freelist) _ptr = ptr;				\
267 									\
268 	*((typeof((array)->freelist) *) _ptr) = (array)->freelist;	\
269 	(array)->freelist = _ptr;					\
270 } while (0)
271 
272 #define array_allocator_init(array)					\
273 do {									\
274 	typeof((array)->freelist) _i;					\
275 									\
276 	BUILD_BUG_ON(sizeof((array)->data[0]) < sizeof(void *));	\
277 	(array)->freelist = NULL;					\
278 									\
279 	for (_i = (array)->data;					\
280 	     _i < (array)->data + ARRAY_SIZE((array)->data);		\
281 	     _i++)							\
282 		array_free(array, _i);					\
283 } while (0)
284 
285 #define array_freelist_empty(array)	((array)->freelist == NULL)
286 
287 #define ANYSINT_MAX(t)							\
288 	((((t) 1 << (sizeof(t) * 8 - 2)) - (t) 1) * (t) 2 + (t) 1)
289 
290 int bch_strtoint_h(const char *cp, int *res);
291 int bch_strtouint_h(const char *cp, unsigned int *res);
292 int bch_strtoll_h(const char *cp, long long *res);
293 int bch_strtoull_h(const char *cp, unsigned long long *res);
294 
295 static inline int bch_strtol_h(const char *cp, long *res)
296 {
297 #if BITS_PER_LONG == 32
298 	return bch_strtoint_h(cp, (int *) res);
299 #else
300 	return bch_strtoll_h(cp, (long long *) res);
301 #endif
302 }
303 
304 static inline int bch_strtoul_h(const char *cp, long *res)
305 {
306 #if BITS_PER_LONG == 32
307 	return bch_strtouint_h(cp, (unsigned int *) res);
308 #else
309 	return bch_strtoull_h(cp, (unsigned long long *) res);
310 #endif
311 }
312 
313 #define strtoi_h(cp, res)						\
314 	(__builtin_types_compatible_p(typeof(*res), int)		\
315 	? bch_strtoint_h(cp, (void *) res)				\
316 	: __builtin_types_compatible_p(typeof(*res), long)		\
317 	? bch_strtol_h(cp, (void *) res)				\
318 	: __builtin_types_compatible_p(typeof(*res), long long)		\
319 	? bch_strtoll_h(cp, (void *) res)				\
320 	: __builtin_types_compatible_p(typeof(*res), unsigned int)	\
321 	? bch_strtouint_h(cp, (void *) res)				\
322 	: __builtin_types_compatible_p(typeof(*res), unsigned long)	\
323 	? bch_strtoul_h(cp, (void *) res)				\
324 	: __builtin_types_compatible_p(typeof(*res), unsigned long long)\
325 	? bch_strtoull_h(cp, (void *) res) : -EINVAL)
326 
327 #define strtoul_safe(cp, var)						\
328 ({									\
329 	unsigned long _v;						\
330 	int _r = kstrtoul(cp, 10, &_v);					\
331 	if (!_r)							\
332 		var = _v;						\
333 	_r;								\
334 })
335 
336 #define strtoul_safe_clamp(cp, var, min, max)				\
337 ({									\
338 	unsigned long _v;						\
339 	int _r = kstrtoul(cp, 10, &_v);					\
340 	if (!_r)							\
341 		var = clamp_t(typeof(var), _v, min, max);		\
342 	_r;								\
343 })
344 
345 #define snprint(buf, size, var)						\
346 	snprintf(buf, size,						\
347 		__builtin_types_compatible_p(typeof(var), int)		\
348 		     ? "%i\n" :						\
349 		__builtin_types_compatible_p(typeof(var), unsigned int)	\
350 		     ? "%u\n" :						\
351 		__builtin_types_compatible_p(typeof(var), long)		\
352 		     ? "%li\n" :					\
353 		__builtin_types_compatible_p(typeof(var), unsigned long)\
354 		     ? "%lu\n" :					\
355 		__builtin_types_compatible_p(typeof(var), int64_t)	\
356 		     ? "%lli\n" :					\
357 		__builtin_types_compatible_p(typeof(var), uint64_t)	\
358 		     ? "%llu\n" :					\
359 		__builtin_types_compatible_p(typeof(var), const char *)	\
360 		     ? "%s\n" : "%i\n", var)
361 
362 ssize_t bch_hprint(char *buf, int64_t v);
363 
364 bool bch_is_zero(const char *p, size_t n);
365 int bch_parse_uuid(const char *s, char *uuid);
366 
367 struct time_stats {
368 	spinlock_t	lock;
369 	/*
370 	 * all fields are in nanoseconds, averages are ewmas stored left shifted
371 	 * by 8
372 	 */
373 	uint64_t	max_duration;
374 	uint64_t	average_duration;
375 	uint64_t	average_frequency;
376 	uint64_t	last;
377 };
378 
379 void bch_time_stats_update(struct time_stats *stats, uint64_t time);
380 
381 static inline unsigned int local_clock_us(void)
382 {
383 	return local_clock() >> 10;
384 }
385 
386 #define NSEC_PER_ns			1L
387 #define NSEC_PER_us			NSEC_PER_USEC
388 #define NSEC_PER_ms			NSEC_PER_MSEC
389 #define NSEC_PER_sec			NSEC_PER_SEC
390 
391 #define __print_time_stat(stats, name, stat, units)			\
392 	sysfs_print(name ## _ ## stat ## _ ## units,			\
393 		    div_u64((stats)->stat >> 8, NSEC_PER_ ## units))
394 
395 #define sysfs_print_time_stats(stats, name,				\
396 			       frequency_units,				\
397 			       duration_units)				\
398 do {									\
399 	__print_time_stat(stats, name,					\
400 			  average_frequency,	frequency_units);	\
401 	__print_time_stat(stats, name,					\
402 			  average_duration,	duration_units);	\
403 	sysfs_print(name ## _ ##max_duration ## _ ## duration_units,	\
404 			div_u64((stats)->max_duration,			\
405 				NSEC_PER_ ## duration_units));		\
406 									\
407 	sysfs_print(name ## _last_ ## frequency_units, (stats)->last	\
408 		    ? div_s64(local_clock() - (stats)->last,		\
409 			      NSEC_PER_ ## frequency_units)		\
410 		    : -1LL);						\
411 } while (0)
412 
413 #define sysfs_time_stats_attribute(name,				\
414 				   frequency_units,			\
415 				   duration_units)			\
416 read_attribute(name ## _average_frequency_ ## frequency_units);		\
417 read_attribute(name ## _average_duration_ ## duration_units);		\
418 read_attribute(name ## _max_duration_ ## duration_units);		\
419 read_attribute(name ## _last_ ## frequency_units)
420 
421 #define sysfs_time_stats_attribute_list(name,				\
422 					frequency_units,		\
423 					duration_units)			\
424 &sysfs_ ## name ## _average_frequency_ ## frequency_units,		\
425 &sysfs_ ## name ## _average_duration_ ## duration_units,		\
426 &sysfs_ ## name ## _max_duration_ ## duration_units,			\
427 &sysfs_ ## name ## _last_ ## frequency_units,
428 
429 #define ewma_add(ewma, val, weight, factor)				\
430 ({									\
431 	(ewma) *= (weight) - 1;						\
432 	(ewma) += (val) << factor;					\
433 	(ewma) /= (weight);						\
434 	(ewma) >> factor;						\
435 })
436 
437 struct bch_ratelimit {
438 	/* Next time we want to do some work, in nanoseconds */
439 	uint64_t		next;
440 
441 	/*
442 	 * Rate at which we want to do work, in units per second
443 	 * The units here correspond to the units passed to bch_next_delay()
444 	 */
445 	atomic_long_t		rate;
446 };
447 
448 static inline void bch_ratelimit_reset(struct bch_ratelimit *d)
449 {
450 	d->next = local_clock();
451 }
452 
453 uint64_t bch_next_delay(struct bch_ratelimit *d, uint64_t done);
454 
455 #define __DIV_SAFE(n, d, zero)						\
456 ({									\
457 	typeof(n) _n = (n);						\
458 	typeof(d) _d = (d);						\
459 	_d ? _n / _d : zero;						\
460 })
461 
462 #define DIV_SAFE(n, d)	__DIV_SAFE(n, d, 0)
463 
464 #define container_of_or_null(ptr, type, member)				\
465 ({									\
466 	typeof(ptr) _ptr = ptr;						\
467 	_ptr ? container_of(_ptr, type, member) : NULL;			\
468 })
469 
470 #define RB_INSERT(root, new, member, cmp)				\
471 ({									\
472 	__label__ dup;							\
473 	struct rb_node **n = &(root)->rb_node, *parent = NULL;		\
474 	typeof(new) this;						\
475 	int res, ret = -1;						\
476 									\
477 	while (*n) {							\
478 		parent = *n;						\
479 		this = container_of(*n, typeof(*(new)), member);	\
480 		res = cmp(new, this);					\
481 		if (!res)						\
482 			goto dup;					\
483 		n = res < 0						\
484 			? &(*n)->rb_left				\
485 			: &(*n)->rb_right;				\
486 	}								\
487 									\
488 	rb_link_node(&(new)->member, parent, n);			\
489 	rb_insert_color(&(new)->member, root);				\
490 	ret = 0;							\
491 dup:									\
492 	ret;								\
493 })
494 
495 #define RB_SEARCH(root, search, member, cmp)				\
496 ({									\
497 	struct rb_node *n = (root)->rb_node;				\
498 	typeof(&(search)) this, ret = NULL;				\
499 	int res;							\
500 									\
501 	while (n) {							\
502 		this = container_of(n, typeof(search), member);		\
503 		res = cmp(&(search), this);				\
504 		if (!res) {						\
505 			ret = this;					\
506 			break;						\
507 		}							\
508 		n = res < 0						\
509 			? n->rb_left					\
510 			: n->rb_right;					\
511 	}								\
512 	ret;								\
513 })
514 
515 #define RB_GREATER(root, search, member, cmp)				\
516 ({									\
517 	struct rb_node *n = (root)->rb_node;				\
518 	typeof(&(search)) this, ret = NULL;				\
519 	int res;							\
520 									\
521 	while (n) {							\
522 		this = container_of(n, typeof(search), member);		\
523 		res = cmp(&(search), this);				\
524 		if (res < 0) {						\
525 			ret = this;					\
526 			n = n->rb_left;					\
527 		} else							\
528 			n = n->rb_right;				\
529 	}								\
530 	ret;								\
531 })
532 
533 #define RB_FIRST(root, type, member)					\
534 	container_of_or_null(rb_first(root), type, member)
535 
536 #define RB_LAST(root, type, member)					\
537 	container_of_or_null(rb_last(root), type, member)
538 
539 #define RB_NEXT(ptr, member)						\
540 	container_of_or_null(rb_next(&(ptr)->member), typeof(*ptr), member)
541 
542 #define RB_PREV(ptr, member)						\
543 	container_of_or_null(rb_prev(&(ptr)->member), typeof(*ptr), member)
544 
545 static inline uint64_t bch_crc64(const void *p, size_t len)
546 {
547 	uint64_t crc = 0xffffffffffffffffULL;
548 
549 	crc = crc64_be(crc, p, len);
550 	return crc ^ 0xffffffffffffffffULL;
551 }
552 
553 static inline uint64_t bch_crc64_update(uint64_t crc,
554 					const void *p,
555 					size_t len)
556 {
557 	crc = crc64_be(crc, p, len);
558 	return crc;
559 }
560 
561 /*
562  * A stepwise-linear pseudo-exponential.  This returns 1 << (x >>
563  * frac_bits), with the less-significant bits filled in by linear
564  * interpolation.
565  *
566  * This can also be interpreted as a floating-point number format,
567  * where the low frac_bits are the mantissa (with implicit leading
568  * 1 bit), and the more significant bits are the exponent.
569  * The return value is 1.mantissa * 2^exponent.
570  *
571  * The way this is used, fract_bits is 6 and the largest possible
572  * input is CONGESTED_MAX-1 = 1023 (exponent 16, mantissa 0x1.fc),
573  * so the maximum output is 0x1fc00.
574  */
575 static inline unsigned int fract_exp_two(unsigned int x,
576 					 unsigned int fract_bits)
577 {
578 	unsigned int mantissa = 1 << fract_bits;	/* Implicit bit */
579 
580 	mantissa += x & (mantissa - 1);
581 	x >>= fract_bits;	/* The exponent */
582 	/* Largest intermediate value 0x7f0000 */
583 	return mantissa << x >> fract_bits;
584 }
585 
586 void bch_bio_map(struct bio *bio, void *base);
587 int bch_bio_alloc_pages(struct bio *bio, gfp_t gfp_mask);
588 
589 static inline sector_t bdev_sectors(struct block_device *bdev)
590 {
591 	return bdev->bd_inode->i_size >> 9;
592 }
593 #endif /* _BCACHE_UTIL_H */
594