xref: /openbmc/linux/drivers/md/bcache/util.h (revision 6d99a79c)
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 heap_empty(h)	((h)->used == 0)
117 
118 #define DECLARE_FIFO(type, name)					\
119 	struct {							\
120 		size_t front, back, size, mask;				\
121 		type *data;						\
122 	} name
123 
124 #define fifo_for_each(c, fifo, iter)					\
125 	for (iter = (fifo)->front;					\
126 	     c = (fifo)->data[iter], iter != (fifo)->back;		\
127 	     iter = (iter + 1) & (fifo)->mask)
128 
129 #define __init_fifo(fifo, gfp)						\
130 ({									\
131 	size_t _allocated_size, _bytes;					\
132 	BUG_ON(!(fifo)->size);						\
133 									\
134 	_allocated_size = roundup_pow_of_two((fifo)->size + 1);		\
135 	_bytes = _allocated_size * sizeof(*(fifo)->data);		\
136 									\
137 	(fifo)->mask = _allocated_size - 1;				\
138 	(fifo)->front = (fifo)->back = 0;				\
139 									\
140 	(fifo)->data = kvmalloc(_bytes, (gfp) & GFP_KERNEL);		\
141 	(fifo)->data;							\
142 })
143 
144 #define init_fifo_exact(fifo, _size, gfp)				\
145 ({									\
146 	(fifo)->size = (_size);						\
147 	__init_fifo(fifo, gfp);						\
148 })
149 
150 #define init_fifo(fifo, _size, gfp)					\
151 ({									\
152 	(fifo)->size = (_size);						\
153 	if ((fifo)->size > 4)						\
154 		(fifo)->size = roundup_pow_of_two((fifo)->size) - 1;	\
155 	__init_fifo(fifo, gfp);						\
156 })
157 
158 #define free_fifo(fifo)							\
159 do {									\
160 	kvfree((fifo)->data);						\
161 	(fifo)->data = NULL;						\
162 } while (0)
163 
164 #define fifo_used(fifo)		(((fifo)->back - (fifo)->front) & (fifo)->mask)
165 #define fifo_free(fifo)		((fifo)->size - fifo_used(fifo))
166 
167 #define fifo_empty(fifo)	(!fifo_used(fifo))
168 #define fifo_full(fifo)		(!fifo_free(fifo))
169 
170 #define fifo_front(fifo)	((fifo)->data[(fifo)->front])
171 #define fifo_back(fifo)							\
172 	((fifo)->data[((fifo)->back - 1) & (fifo)->mask])
173 
174 #define fifo_idx(fifo, p)	(((p) - &fifo_front(fifo)) & (fifo)->mask)
175 
176 #define fifo_push_back(fifo, i)						\
177 ({									\
178 	bool _r = !fifo_full((fifo));					\
179 	if (_r) {							\
180 		(fifo)->data[(fifo)->back++] = (i);			\
181 		(fifo)->back &= (fifo)->mask;				\
182 	}								\
183 	_r;								\
184 })
185 
186 #define fifo_pop_front(fifo, i)						\
187 ({									\
188 	bool _r = !fifo_empty((fifo));					\
189 	if (_r) {							\
190 		(i) = (fifo)->data[(fifo)->front++];			\
191 		(fifo)->front &= (fifo)->mask;				\
192 	}								\
193 	_r;								\
194 })
195 
196 #define fifo_push_front(fifo, i)					\
197 ({									\
198 	bool _r = !fifo_full((fifo));					\
199 	if (_r) {							\
200 		--(fifo)->front;					\
201 		(fifo)->front &= (fifo)->mask;				\
202 		(fifo)->data[(fifo)->front] = (i);			\
203 	}								\
204 	_r;								\
205 })
206 
207 #define fifo_pop_back(fifo, i)						\
208 ({									\
209 	bool _r = !fifo_empty((fifo));					\
210 	if (_r) {							\
211 		--(fifo)->back;						\
212 		(fifo)->back &= (fifo)->mask;				\
213 		(i) = (fifo)->data[(fifo)->back]			\
214 	}								\
215 	_r;								\
216 })
217 
218 #define fifo_push(fifo, i)	fifo_push_back(fifo, (i))
219 #define fifo_pop(fifo, i)	fifo_pop_front(fifo, (i))
220 
221 #define fifo_swap(l, r)							\
222 do {									\
223 	swap((l)->front, (r)->front);					\
224 	swap((l)->back, (r)->back);					\
225 	swap((l)->size, (r)->size);					\
226 	swap((l)->mask, (r)->mask);					\
227 	swap((l)->data, (r)->data);					\
228 } while (0)
229 
230 #define fifo_move(dest, src)						\
231 do {									\
232 	typeof(*((dest)->data)) _t;					\
233 	while (!fifo_full(dest) &&					\
234 	       fifo_pop(src, _t))					\
235 		fifo_push(dest, _t);					\
236 } while (0)
237 
238 /*
239  * Simple array based allocator - preallocates a number of elements and you can
240  * never allocate more than that, also has no locking.
241  *
242  * Handy because if you know you only need a fixed number of elements you don't
243  * have to worry about memory allocation failure, and sometimes a mempool isn't
244  * what you want.
245  *
246  * We treat the free elements as entries in a singly linked list, and the
247  * freelist as a stack - allocating and freeing push and pop off the freelist.
248  */
249 
250 #define DECLARE_ARRAY_ALLOCATOR(type, name, size)			\
251 	struct {							\
252 		type	*freelist;					\
253 		type	data[size];					\
254 	} name
255 
256 #define array_alloc(array)						\
257 ({									\
258 	typeof((array)->freelist) _ret = (array)->freelist;		\
259 									\
260 	if (_ret)							\
261 		(array)->freelist = *((typeof((array)->freelist) *) _ret);\
262 									\
263 	_ret;								\
264 })
265 
266 #define array_free(array, ptr)						\
267 do {									\
268 	typeof((array)->freelist) _ptr = ptr;				\
269 									\
270 	*((typeof((array)->freelist) *) _ptr) = (array)->freelist;	\
271 	(array)->freelist = _ptr;					\
272 } while (0)
273 
274 #define array_allocator_init(array)					\
275 do {									\
276 	typeof((array)->freelist) _i;					\
277 									\
278 	BUILD_BUG_ON(sizeof((array)->data[0]) < sizeof(void *));	\
279 	(array)->freelist = NULL;					\
280 									\
281 	for (_i = (array)->data;					\
282 	     _i < (array)->data + ARRAY_SIZE((array)->data);		\
283 	     _i++)							\
284 		array_free(array, _i);					\
285 } while (0)
286 
287 #define array_freelist_empty(array)	((array)->freelist == NULL)
288 
289 #define ANYSINT_MAX(t)							\
290 	((((t) 1 << (sizeof(t) * 8 - 2)) - (t) 1) * (t) 2 + (t) 1)
291 
292 int bch_strtoint_h(const char *cp, int *res);
293 int bch_strtouint_h(const char *cp, unsigned int *res);
294 int bch_strtoll_h(const char *cp, long long *res);
295 int bch_strtoull_h(const char *cp, unsigned long long *res);
296 
297 static inline int bch_strtol_h(const char *cp, long *res)
298 {
299 #if BITS_PER_LONG == 32
300 	return bch_strtoint_h(cp, (int *) res);
301 #else
302 	return bch_strtoll_h(cp, (long long *) res);
303 #endif
304 }
305 
306 static inline int bch_strtoul_h(const char *cp, long *res)
307 {
308 #if BITS_PER_LONG == 32
309 	return bch_strtouint_h(cp, (unsigned int *) res);
310 #else
311 	return bch_strtoull_h(cp, (unsigned long long *) res);
312 #endif
313 }
314 
315 #define strtoi_h(cp, res)						\
316 	(__builtin_types_compatible_p(typeof(*res), int)		\
317 	? bch_strtoint_h(cp, (void *) res)				\
318 	: __builtin_types_compatible_p(typeof(*res), long)		\
319 	? bch_strtol_h(cp, (void *) res)				\
320 	: __builtin_types_compatible_p(typeof(*res), long long)		\
321 	? bch_strtoll_h(cp, (void *) res)				\
322 	: __builtin_types_compatible_p(typeof(*res), unsigned int)	\
323 	? bch_strtouint_h(cp, (void *) res)				\
324 	: __builtin_types_compatible_p(typeof(*res), unsigned long)	\
325 	? bch_strtoul_h(cp, (void *) res)				\
326 	: __builtin_types_compatible_p(typeof(*res), unsigned long long)\
327 	? bch_strtoull_h(cp, (void *) res) : -EINVAL)
328 
329 #define strtoul_safe(cp, var)						\
330 ({									\
331 	unsigned long _v;						\
332 	int _r = kstrtoul(cp, 10, &_v);					\
333 	if (!_r)							\
334 		var = _v;						\
335 	_r;								\
336 })
337 
338 #define strtoul_safe_clamp(cp, var, min, max)				\
339 ({									\
340 	unsigned long _v;						\
341 	int _r = kstrtoul(cp, 10, &_v);					\
342 	if (!_r)							\
343 		var = clamp_t(typeof(var), _v, min, max);		\
344 	_r;								\
345 })
346 
347 #define snprint(buf, size, var)						\
348 	snprintf(buf, size,						\
349 		__builtin_types_compatible_p(typeof(var), int)		\
350 		     ? "%i\n" :						\
351 		__builtin_types_compatible_p(typeof(var), unsigned int)	\
352 		     ? "%u\n" :						\
353 		__builtin_types_compatible_p(typeof(var), long)		\
354 		     ? "%li\n" :					\
355 		__builtin_types_compatible_p(typeof(var), unsigned long)\
356 		     ? "%lu\n" :					\
357 		__builtin_types_compatible_p(typeof(var), int64_t)	\
358 		     ? "%lli\n" :					\
359 		__builtin_types_compatible_p(typeof(var), uint64_t)	\
360 		     ? "%llu\n" :					\
361 		__builtin_types_compatible_p(typeof(var), const char *)	\
362 		     ? "%s\n" : "%i\n", var)
363 
364 ssize_t bch_hprint(char *buf, int64_t v);
365 
366 bool bch_is_zero(const char *p, size_t n);
367 int bch_parse_uuid(const char *s, char *uuid);
368 
369 struct time_stats {
370 	spinlock_t	lock;
371 	/*
372 	 * all fields are in nanoseconds, averages are ewmas stored left shifted
373 	 * by 8
374 	 */
375 	uint64_t	max_duration;
376 	uint64_t	average_duration;
377 	uint64_t	average_frequency;
378 	uint64_t	last;
379 };
380 
381 void bch_time_stats_update(struct time_stats *stats, uint64_t time);
382 
383 static inline unsigned int local_clock_us(void)
384 {
385 	return local_clock() >> 10;
386 }
387 
388 #define NSEC_PER_ns			1L
389 #define NSEC_PER_us			NSEC_PER_USEC
390 #define NSEC_PER_ms			NSEC_PER_MSEC
391 #define NSEC_PER_sec			NSEC_PER_SEC
392 
393 #define __print_time_stat(stats, name, stat, units)			\
394 	sysfs_print(name ## _ ## stat ## _ ## units,			\
395 		    div_u64((stats)->stat >> 8, NSEC_PER_ ## units))
396 
397 #define sysfs_print_time_stats(stats, name,				\
398 			       frequency_units,				\
399 			       duration_units)				\
400 do {									\
401 	__print_time_stat(stats, name,					\
402 			  average_frequency,	frequency_units);	\
403 	__print_time_stat(stats, name,					\
404 			  average_duration,	duration_units);	\
405 	sysfs_print(name ## _ ##max_duration ## _ ## duration_units,	\
406 			div_u64((stats)->max_duration,			\
407 				NSEC_PER_ ## duration_units));		\
408 									\
409 	sysfs_print(name ## _last_ ## frequency_units, (stats)->last	\
410 		    ? div_s64(local_clock() - (stats)->last,		\
411 			      NSEC_PER_ ## frequency_units)		\
412 		    : -1LL);						\
413 } while (0)
414 
415 #define sysfs_time_stats_attribute(name,				\
416 				   frequency_units,			\
417 				   duration_units)			\
418 read_attribute(name ## _average_frequency_ ## frequency_units);		\
419 read_attribute(name ## _average_duration_ ## duration_units);		\
420 read_attribute(name ## _max_duration_ ## duration_units);		\
421 read_attribute(name ## _last_ ## frequency_units)
422 
423 #define sysfs_time_stats_attribute_list(name,				\
424 					frequency_units,		\
425 					duration_units)			\
426 &sysfs_ ## name ## _average_frequency_ ## frequency_units,		\
427 &sysfs_ ## name ## _average_duration_ ## duration_units,		\
428 &sysfs_ ## name ## _max_duration_ ## duration_units,			\
429 &sysfs_ ## name ## _last_ ## frequency_units,
430 
431 #define ewma_add(ewma, val, weight, factor)				\
432 ({									\
433 	(ewma) *= (weight) - 1;						\
434 	(ewma) += (val) << factor;					\
435 	(ewma) /= (weight);						\
436 	(ewma) >> factor;						\
437 })
438 
439 struct bch_ratelimit {
440 	/* Next time we want to do some work, in nanoseconds */
441 	uint64_t		next;
442 
443 	/*
444 	 * Rate at which we want to do work, in units per second
445 	 * The units here correspond to the units passed to bch_next_delay()
446 	 */
447 	atomic_long_t		rate;
448 };
449 
450 static inline void bch_ratelimit_reset(struct bch_ratelimit *d)
451 {
452 	d->next = local_clock();
453 }
454 
455 uint64_t bch_next_delay(struct bch_ratelimit *d, uint64_t done);
456 
457 #define __DIV_SAFE(n, d, zero)						\
458 ({									\
459 	typeof(n) _n = (n);						\
460 	typeof(d) _d = (d);						\
461 	_d ? _n / _d : zero;						\
462 })
463 
464 #define DIV_SAFE(n, d)	__DIV_SAFE(n, d, 0)
465 
466 #define container_of_or_null(ptr, type, member)				\
467 ({									\
468 	typeof(ptr) _ptr = ptr;						\
469 	_ptr ? container_of(_ptr, type, member) : NULL;			\
470 })
471 
472 #define RB_INSERT(root, new, member, cmp)				\
473 ({									\
474 	__label__ dup;							\
475 	struct rb_node **n = &(root)->rb_node, *parent = NULL;		\
476 	typeof(new) this;						\
477 	int res, ret = -1;						\
478 									\
479 	while (*n) {							\
480 		parent = *n;						\
481 		this = container_of(*n, typeof(*(new)), member);	\
482 		res = cmp(new, this);					\
483 		if (!res)						\
484 			goto dup;					\
485 		n = res < 0						\
486 			? &(*n)->rb_left				\
487 			: &(*n)->rb_right;				\
488 	}								\
489 									\
490 	rb_link_node(&(new)->member, parent, n);			\
491 	rb_insert_color(&(new)->member, root);				\
492 	ret = 0;							\
493 dup:									\
494 	ret;								\
495 })
496 
497 #define RB_SEARCH(root, search, member, cmp)				\
498 ({									\
499 	struct rb_node *n = (root)->rb_node;				\
500 	typeof(&(search)) this, ret = NULL;				\
501 	int res;							\
502 									\
503 	while (n) {							\
504 		this = container_of(n, typeof(search), member);		\
505 		res = cmp(&(search), this);				\
506 		if (!res) {						\
507 			ret = this;					\
508 			break;						\
509 		}							\
510 		n = res < 0						\
511 			? n->rb_left					\
512 			: n->rb_right;					\
513 	}								\
514 	ret;								\
515 })
516 
517 #define RB_GREATER(root, search, member, cmp)				\
518 ({									\
519 	struct rb_node *n = (root)->rb_node;				\
520 	typeof(&(search)) this, ret = NULL;				\
521 	int res;							\
522 									\
523 	while (n) {							\
524 		this = container_of(n, typeof(search), member);		\
525 		res = cmp(&(search), this);				\
526 		if (res < 0) {						\
527 			ret = this;					\
528 			n = n->rb_left;					\
529 		} else							\
530 			n = n->rb_right;				\
531 	}								\
532 	ret;								\
533 })
534 
535 #define RB_FIRST(root, type, member)					\
536 	container_of_or_null(rb_first(root), type, member)
537 
538 #define RB_LAST(root, type, member)					\
539 	container_of_or_null(rb_last(root), type, member)
540 
541 #define RB_NEXT(ptr, member)						\
542 	container_of_or_null(rb_next(&(ptr)->member), typeof(*ptr), member)
543 
544 #define RB_PREV(ptr, member)						\
545 	container_of_or_null(rb_prev(&(ptr)->member), typeof(*ptr), member)
546 
547 static inline uint64_t bch_crc64(const void *p, size_t len)
548 {
549 	uint64_t crc = 0xffffffffffffffffULL;
550 
551 	crc = crc64_be(crc, p, len);
552 	return crc ^ 0xffffffffffffffffULL;
553 }
554 
555 static inline uint64_t bch_crc64_update(uint64_t crc,
556 					const void *p,
557 					size_t len)
558 {
559 	crc = crc64_be(crc, p, len);
560 	return crc;
561 }
562 
563 /* Does linear interpolation between powers of two */
564 static inline unsigned int fract_exp_two(unsigned int x,
565 					 unsigned int fract_bits)
566 {
567 	unsigned int fract = x & ~(~0 << fract_bits);
568 
569 	x >>= fract_bits;
570 	x   = 1 << x;
571 	x  += (x * fract) >> fract_bits;
572 
573 	return x;
574 }
575 
576 void bch_bio_map(struct bio *bio, void *base);
577 int bch_bio_alloc_pages(struct bio *bio, gfp_t gfp_mask);
578 
579 static inline sector_t bdev_sectors(struct block_device *bdev)
580 {
581 	return bdev->bd_inode->i_size >> 9;
582 }
583 #endif /* _BCACHE_UTIL_H */
584