xref: /openbmc/linux/drivers/md/bcache/util.h (revision 3b23dc52)
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 
15 #include "closure.h"
16 
17 #define PAGE_SECTORS		(PAGE_SIZE / 512)
18 
19 struct closure;
20 
21 #ifdef CONFIG_BCACHE_DEBUG
22 
23 #define EBUG_ON(cond)			BUG_ON(cond)
24 #define atomic_dec_bug(v)	BUG_ON(atomic_dec_return(v) < 0)
25 #define atomic_inc_bug(v, i)	BUG_ON(atomic_inc_return(v) <= i)
26 
27 #else /* DEBUG */
28 
29 #define EBUG_ON(cond)			do { if (cond); } while (0)
30 #define atomic_dec_bug(v)	atomic_dec(v)
31 #define atomic_inc_bug(v, i)	atomic_inc(v)
32 
33 #endif
34 
35 #define DECLARE_HEAP(type, name)					\
36 	struct {							\
37 		size_t size, used;					\
38 		type *data;						\
39 	} name
40 
41 #define init_heap(heap, _size, gfp)					\
42 ({									\
43 	size_t _bytes;							\
44 	(heap)->used = 0;						\
45 	(heap)->size = (_size);						\
46 	_bytes = (heap)->size * sizeof(*(heap)->data);			\
47 	(heap)->data = kvmalloc(_bytes, (gfp) & GFP_KERNEL);		\
48 	(heap)->data;							\
49 })
50 
51 #define free_heap(heap)							\
52 do {									\
53 	kvfree((heap)->data);						\
54 	(heap)->data = NULL;						\
55 } while (0)
56 
57 #define heap_swap(h, i, j)	swap((h)->data[i], (h)->data[j])
58 
59 #define heap_sift(h, i, cmp)						\
60 do {									\
61 	size_t _r, _j = i;						\
62 									\
63 	for (; _j * 2 + 1 < (h)->used; _j = _r) {			\
64 		_r = _j * 2 + 1;					\
65 		if (_r + 1 < (h)->used &&				\
66 		    cmp((h)->data[_r], (h)->data[_r + 1]))		\
67 			_r++;						\
68 									\
69 		if (cmp((h)->data[_r], (h)->data[_j]))			\
70 			break;						\
71 		heap_swap(h, _r, _j);					\
72 	}								\
73 } while (0)
74 
75 #define heap_sift_down(h, i, cmp)					\
76 do {									\
77 	while (i) {							\
78 		size_t p = (i - 1) / 2;					\
79 		if (cmp((h)->data[i], (h)->data[p]))			\
80 			break;						\
81 		heap_swap(h, i, p);					\
82 		i = p;							\
83 	}								\
84 } while (0)
85 
86 #define heap_add(h, d, cmp)						\
87 ({									\
88 	bool _r = !heap_full(h);					\
89 	if (_r) {							\
90 		size_t _i = (h)->used++;				\
91 		(h)->data[_i] = d;					\
92 									\
93 		heap_sift_down(h, _i, cmp);				\
94 		heap_sift(h, _i, cmp);					\
95 	}								\
96 	_r;								\
97 })
98 
99 #define heap_pop(h, d, cmp)						\
100 ({									\
101 	bool _r = (h)->used;						\
102 	if (_r) {							\
103 		(d) = (h)->data[0];					\
104 		(h)->used--;						\
105 		heap_swap(h, 0, (h)->used);				\
106 		heap_sift(h, 0, cmp);					\
107 	}								\
108 	_r;								\
109 })
110 
111 #define heap_peek(h)	((h)->used ? (h)->data[0] : NULL)
112 
113 #define heap_full(h)	((h)->used == (h)->size)
114 
115 #define heap_empty(h)	((h)->used == 0)
116 
117 #define DECLARE_FIFO(type, name)					\
118 	struct {							\
119 		size_t front, back, size, mask;				\
120 		type *data;						\
121 	} name
122 
123 #define fifo_for_each(c, fifo, iter)					\
124 	for (iter = (fifo)->front;					\
125 	     c = (fifo)->data[iter], iter != (fifo)->back;		\
126 	     iter = (iter + 1) & (fifo)->mask)
127 
128 #define __init_fifo(fifo, gfp)						\
129 ({									\
130 	size_t _allocated_size, _bytes;					\
131 	BUG_ON(!(fifo)->size);						\
132 									\
133 	_allocated_size = roundup_pow_of_two((fifo)->size + 1);		\
134 	_bytes = _allocated_size * sizeof(*(fifo)->data);		\
135 									\
136 	(fifo)->mask = _allocated_size - 1;				\
137 	(fifo)->front = (fifo)->back = 0;				\
138 									\
139 	(fifo)->data = kvmalloc(_bytes, (gfp) & GFP_KERNEL);		\
140 	(fifo)->data;							\
141 })
142 
143 #define init_fifo_exact(fifo, _size, gfp)				\
144 ({									\
145 	(fifo)->size = (_size);						\
146 	__init_fifo(fifo, gfp);						\
147 })
148 
149 #define init_fifo(fifo, _size, gfp)					\
150 ({									\
151 	(fifo)->size = (_size);						\
152 	if ((fifo)->size > 4)						\
153 		(fifo)->size = roundup_pow_of_two((fifo)->size) - 1;	\
154 	__init_fifo(fifo, gfp);						\
155 })
156 
157 #define free_fifo(fifo)							\
158 do {									\
159 	kvfree((fifo)->data);						\
160 	(fifo)->data = NULL;						\
161 } while (0)
162 
163 #define fifo_used(fifo)		(((fifo)->back - (fifo)->front) & (fifo)->mask)
164 #define fifo_free(fifo)		((fifo)->size - fifo_used(fifo))
165 
166 #define fifo_empty(fifo)	(!fifo_used(fifo))
167 #define fifo_full(fifo)		(!fifo_free(fifo))
168 
169 #define fifo_front(fifo)	((fifo)->data[(fifo)->front])
170 #define fifo_back(fifo)							\
171 	((fifo)->data[((fifo)->back - 1) & (fifo)->mask])
172 
173 #define fifo_idx(fifo, p)	(((p) - &fifo_front(fifo)) & (fifo)->mask)
174 
175 #define fifo_push_back(fifo, i)						\
176 ({									\
177 	bool _r = !fifo_full((fifo));					\
178 	if (_r) {							\
179 		(fifo)->data[(fifo)->back++] = (i);			\
180 		(fifo)->back &= (fifo)->mask;				\
181 	}								\
182 	_r;								\
183 })
184 
185 #define fifo_pop_front(fifo, i)						\
186 ({									\
187 	bool _r = !fifo_empty((fifo));					\
188 	if (_r) {							\
189 		(i) = (fifo)->data[(fifo)->front++];			\
190 		(fifo)->front &= (fifo)->mask;				\
191 	}								\
192 	_r;								\
193 })
194 
195 #define fifo_push_front(fifo, i)					\
196 ({									\
197 	bool _r = !fifo_full((fifo));					\
198 	if (_r) {							\
199 		--(fifo)->front;					\
200 		(fifo)->front &= (fifo)->mask;				\
201 		(fifo)->data[(fifo)->front] = (i);			\
202 	}								\
203 	_r;								\
204 })
205 
206 #define fifo_pop_back(fifo, i)						\
207 ({									\
208 	bool _r = !fifo_empty((fifo));					\
209 	if (_r) {							\
210 		--(fifo)->back;						\
211 		(fifo)->back &= (fifo)->mask;				\
212 		(i) = (fifo)->data[(fifo)->back]			\
213 	}								\
214 	_r;								\
215 })
216 
217 #define fifo_push(fifo, i)	fifo_push_back(fifo, (i))
218 #define fifo_pop(fifo, i)	fifo_pop_front(fifo, (i))
219 
220 #define fifo_swap(l, r)							\
221 do {									\
222 	swap((l)->front, (r)->front);					\
223 	swap((l)->back, (r)->back);					\
224 	swap((l)->size, (r)->size);					\
225 	swap((l)->mask, (r)->mask);					\
226 	swap((l)->data, (r)->data);					\
227 } while (0)
228 
229 #define fifo_move(dest, src)						\
230 do {									\
231 	typeof(*((dest)->data)) _t;					\
232 	while (!fifo_full(dest) &&					\
233 	       fifo_pop(src, _t))					\
234 		fifo_push(dest, _t);					\
235 } while (0)
236 
237 /*
238  * Simple array based allocator - preallocates a number of elements and you can
239  * never allocate more than that, also has no locking.
240  *
241  * Handy because if you know you only need a fixed number of elements you don't
242  * have to worry about memory allocation failure, and sometimes a mempool isn't
243  * what you want.
244  *
245  * We treat the free elements as entries in a singly linked list, and the
246  * freelist as a stack - allocating and freeing push and pop off the freelist.
247  */
248 
249 #define DECLARE_ARRAY_ALLOCATOR(type, name, size)			\
250 	struct {							\
251 		type	*freelist;					\
252 		type	data[size];					\
253 	} name
254 
255 #define array_alloc(array)						\
256 ({									\
257 	typeof((array)->freelist) _ret = (array)->freelist;		\
258 									\
259 	if (_ret)							\
260 		(array)->freelist = *((typeof((array)->freelist) *) _ret);\
261 									\
262 	_ret;								\
263 })
264 
265 #define array_free(array, ptr)						\
266 do {									\
267 	typeof((array)->freelist) _ptr = ptr;				\
268 									\
269 	*((typeof((array)->freelist) *) _ptr) = (array)->freelist;	\
270 	(array)->freelist = _ptr;					\
271 } while (0)
272 
273 #define array_allocator_init(array)					\
274 do {									\
275 	typeof((array)->freelist) _i;					\
276 									\
277 	BUILD_BUG_ON(sizeof((array)->data[0]) < sizeof(void *));	\
278 	(array)->freelist = NULL;					\
279 									\
280 	for (_i = (array)->data;					\
281 	     _i < (array)->data + ARRAY_SIZE((array)->data);		\
282 	     _i++)							\
283 		array_free(array, _i);					\
284 } while (0)
285 
286 #define array_freelist_empty(array)	((array)->freelist == NULL)
287 
288 #define ANYSINT_MAX(t)							\
289 	((((t) 1 << (sizeof(t) * 8 - 2)) - (t) 1) * (t) 2 + (t) 1)
290 
291 int bch_strtoint_h(const char *, int *);
292 int bch_strtouint_h(const char *, unsigned int *);
293 int bch_strtoll_h(const char *, long long *);
294 int bch_strtoull_h(const char *, unsigned long long *);
295 
296 static inline int bch_strtol_h(const char *cp, long *res)
297 {
298 #if BITS_PER_LONG == 32
299 	return bch_strtoint_h(cp, (int *) res);
300 #else
301 	return bch_strtoll_h(cp, (long long *) res);
302 #endif
303 }
304 
305 static inline int bch_strtoul_h(const char *cp, long *res)
306 {
307 #if BITS_PER_LONG == 32
308 	return bch_strtouint_h(cp, (unsigned int *) res);
309 #else
310 	return bch_strtoull_h(cp, (unsigned long long *) res);
311 #endif
312 }
313 
314 #define strtoi_h(cp, res)						\
315 	(__builtin_types_compatible_p(typeof(*res), int)		\
316 	? bch_strtoint_h(cp, (void *) res)				\
317 	: __builtin_types_compatible_p(typeof(*res), long)		\
318 	? bch_strtol_h(cp, (void *) res)				\
319 	: __builtin_types_compatible_p(typeof(*res), long long)		\
320 	? bch_strtoll_h(cp, (void *) res)				\
321 	: __builtin_types_compatible_p(typeof(*res), unsigned int)	\
322 	? bch_strtouint_h(cp, (void *) res)				\
323 	: __builtin_types_compatible_p(typeof(*res), unsigned long)	\
324 	? bch_strtoul_h(cp, (void *) res)				\
325 	: __builtin_types_compatible_p(typeof(*res), unsigned long long)\
326 	? bch_strtoull_h(cp, (void *) res) : -EINVAL)
327 
328 #define strtoul_safe(cp, var)						\
329 ({									\
330 	unsigned long _v;						\
331 	int _r = kstrtoul(cp, 10, &_v);					\
332 	if (!_r)							\
333 		var = _v;						\
334 	_r;								\
335 })
336 
337 #define strtoul_safe_clamp(cp, var, min, max)				\
338 ({									\
339 	unsigned long _v;						\
340 	int _r = kstrtoul(cp, 10, &_v);					\
341 	if (!_r)							\
342 		var = clamp_t(typeof(var), _v, min, max);		\
343 	_r;								\
344 })
345 
346 #define snprint(buf, size, var)						\
347 	snprintf(buf, size,						\
348 		__builtin_types_compatible_p(typeof(var), int)		\
349 		     ? "%i\n" :						\
350 		__builtin_types_compatible_p(typeof(var), unsigned)	\
351 		     ? "%u\n" :						\
352 		__builtin_types_compatible_p(typeof(var), long)		\
353 		     ? "%li\n" :					\
354 		__builtin_types_compatible_p(typeof(var), unsigned long)\
355 		     ? "%lu\n" :					\
356 		__builtin_types_compatible_p(typeof(var), int64_t)	\
357 		     ? "%lli\n" :					\
358 		__builtin_types_compatible_p(typeof(var), uint64_t)	\
359 		     ? "%llu\n" :					\
360 		__builtin_types_compatible_p(typeof(var), const char *)	\
361 		     ? "%s\n" : "%i\n", var)
362 
363 ssize_t bch_hprint(char *buf, int64_t v);
364 
365 bool bch_is_zero(const char *p, size_t n);
366 int bch_parse_uuid(const char *s, char *uuid);
367 
368 struct time_stats {
369 	spinlock_t	lock;
370 	/*
371 	 * all fields are in nanoseconds, averages are ewmas stored left shifted
372 	 * by 8
373 	 */
374 	uint64_t	max_duration;
375 	uint64_t	average_duration;
376 	uint64_t	average_frequency;
377 	uint64_t	last;
378 };
379 
380 void bch_time_stats_update(struct time_stats *stats, uint64_t time);
381 
382 static inline unsigned local_clock_us(void)
383 {
384 	return local_clock() >> 10;
385 }
386 
387 #define NSEC_PER_ns			1L
388 #define NSEC_PER_us			NSEC_PER_USEC
389 #define NSEC_PER_ms			NSEC_PER_MSEC
390 #define NSEC_PER_sec			NSEC_PER_SEC
391 
392 #define __print_time_stat(stats, name, stat, units)			\
393 	sysfs_print(name ## _ ## stat ## _ ## units,			\
394 		    div_u64((stats)->stat >> 8, NSEC_PER_ ## units))
395 
396 #define sysfs_print_time_stats(stats, name,				\
397 			       frequency_units,				\
398 			       duration_units)				\
399 do {									\
400 	__print_time_stat(stats, name,					\
401 			  average_frequency,	frequency_units);	\
402 	__print_time_stat(stats, name,					\
403 			  average_duration,	duration_units);	\
404 	sysfs_print(name ## _ ##max_duration ## _ ## duration_units,	\
405 			div_u64((stats)->max_duration, 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 	uint32_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 /* Does linear interpolation between powers of two */
546 static inline unsigned fract_exp_two(unsigned x, unsigned fract_bits)
547 {
548 	unsigned fract = x & ~(~0 << fract_bits);
549 
550 	x >>= fract_bits;
551 	x   = 1 << x;
552 	x  += (x * fract) >> fract_bits;
553 
554 	return x;
555 }
556 
557 void bch_bio_map(struct bio *bio, void *base);
558 int bch_bio_alloc_pages(struct bio *bio, gfp_t gfp_mask);
559 
560 static inline sector_t bdev_sectors(struct block_device *bdev)
561 {
562 	return bdev->bd_inode->i_size >> 9;
563 }
564 
565 uint64_t bch_crc64_update(uint64_t, const void *, size_t);
566 uint64_t bch_crc64(const void *, size_t);
567 
568 #endif /* _BCACHE_UTIL_H */
569