xref: /linux/drivers/md/bcache/util.h (revision c98be0c96db00e9b6b02d31e0fa7590c54cdaaac)
1 
2 #ifndef _BCACHE_UTIL_H
3 #define _BCACHE_UTIL_H
4 
5 #include <linux/blkdev.h>
6 #include <linux/errno.h>
7 #include <linux/kernel.h>
8 #include <linux/llist.h>
9 #include <linux/ratelimit.h>
10 #include <linux/vmalloc.h>
11 #include <linux/workqueue.h>
12 
13 #include "closure.h"
14 
15 #define PAGE_SECTORS		(PAGE_SIZE / 512)
16 
17 struct closure;
18 
19 #ifdef CONFIG_BCACHE_DEBUG
20 
21 #define EBUG_ON(cond)			BUG_ON(cond)
22 #define atomic_dec_bug(v)	BUG_ON(atomic_dec_return(v) < 0)
23 #define atomic_inc_bug(v, i)	BUG_ON(atomic_inc_return(v) <= i)
24 
25 #else /* DEBUG */
26 
27 #define EBUG_ON(cond)			do { if (cond); } while (0)
28 #define atomic_dec_bug(v)	atomic_dec(v)
29 #define atomic_inc_bug(v, i)	atomic_inc(v)
30 
31 #endif
32 
33 #define DECLARE_HEAP(type, name)					\
34 	struct {							\
35 		size_t size, used;					\
36 		type *data;						\
37 	} name
38 
39 #define init_heap(heap, _size, gfp)					\
40 ({									\
41 	size_t _bytes;							\
42 	(heap)->used = 0;						\
43 	(heap)->size = (_size);						\
44 	_bytes = (heap)->size * sizeof(*(heap)->data);			\
45 	(heap)->data = NULL;						\
46 	if (_bytes < KMALLOC_MAX_SIZE)					\
47 		(heap)->data = kmalloc(_bytes, (gfp));			\
48 	if ((!(heap)->data) && ((gfp) & GFP_KERNEL))			\
49 		(heap)->data = vmalloc(_bytes);				\
50 	(heap)->data;							\
51 })
52 
53 #define free_heap(heap)							\
54 do {									\
55 	if (is_vmalloc_addr((heap)->data))				\
56 		vfree((heap)->data);					\
57 	else								\
58 		kfree((heap)->data);					\
59 	(heap)->data = NULL;						\
60 } while (0)
61 
62 #define heap_swap(h, i, j)	swap((h)->data[i], (h)->data[j])
63 
64 #define heap_sift(h, i, cmp)						\
65 do {									\
66 	size_t _r, _j = i;						\
67 									\
68 	for (; _j * 2 + 1 < (h)->used; _j = _r) {			\
69 		_r = _j * 2 + 1;					\
70 		if (_r + 1 < (h)->used &&				\
71 		    cmp((h)->data[_r], (h)->data[_r + 1]))		\
72 			_r++;						\
73 									\
74 		if (cmp((h)->data[_r], (h)->data[_j]))			\
75 			break;						\
76 		heap_swap(h, _r, _j);					\
77 	}								\
78 } while (0)
79 
80 #define heap_sift_down(h, i, cmp)					\
81 do {									\
82 	while (i) {							\
83 		size_t p = (i - 1) / 2;					\
84 		if (cmp((h)->data[i], (h)->data[p]))			\
85 			break;						\
86 		heap_swap(h, i, p);					\
87 		i = p;							\
88 	}								\
89 } while (0)
90 
91 #define heap_add(h, d, cmp)						\
92 ({									\
93 	bool _r = !heap_full(h);					\
94 	if (_r) {							\
95 		size_t _i = (h)->used++;				\
96 		(h)->data[_i] = d;					\
97 									\
98 		heap_sift_down(h, _i, cmp);				\
99 		heap_sift(h, _i, cmp);					\
100 	}								\
101 	_r;								\
102 })
103 
104 #define heap_pop(h, d, cmp)						\
105 ({									\
106 	bool _r = (h)->used;						\
107 	if (_r) {							\
108 		(d) = (h)->data[0];					\
109 		(h)->used--;						\
110 		heap_swap(h, 0, (h)->used);				\
111 		heap_sift(h, 0, cmp);					\
112 	}								\
113 	_r;								\
114 })
115 
116 #define heap_peek(h)	((h)->used ? (h)->data[0] : NULL)
117 
118 #define heap_full(h)	((h)->used == (h)->size)
119 
120 #define DECLARE_FIFO(type, name)					\
121 	struct {							\
122 		size_t front, back, size, mask;				\
123 		type *data;						\
124 	} name
125 
126 #define fifo_for_each(c, fifo, iter)					\
127 	for (iter = (fifo)->front;					\
128 	     c = (fifo)->data[iter], iter != (fifo)->back;		\
129 	     iter = (iter + 1) & (fifo)->mask)
130 
131 #define __init_fifo(fifo, gfp)						\
132 ({									\
133 	size_t _allocated_size, _bytes;					\
134 	BUG_ON(!(fifo)->size);						\
135 									\
136 	_allocated_size = roundup_pow_of_two((fifo)->size + 1);		\
137 	_bytes = _allocated_size * sizeof(*(fifo)->data);		\
138 									\
139 	(fifo)->mask = _allocated_size - 1;				\
140 	(fifo)->front = (fifo)->back = 0;				\
141 	(fifo)->data = NULL;						\
142 									\
143 	if (_bytes < KMALLOC_MAX_SIZE)					\
144 		(fifo)->data = kmalloc(_bytes, (gfp));			\
145 	if ((!(fifo)->data) && ((gfp) & GFP_KERNEL))			\
146 		(fifo)->data = vmalloc(_bytes);				\
147 	(fifo)->data;							\
148 })
149 
150 #define init_fifo_exact(fifo, _size, gfp)				\
151 ({									\
152 	(fifo)->size = (_size);						\
153 	__init_fifo(fifo, gfp);						\
154 })
155 
156 #define init_fifo(fifo, _size, gfp)					\
157 ({									\
158 	(fifo)->size = (_size);						\
159 	if ((fifo)->size > 4)						\
160 		(fifo)->size = roundup_pow_of_two((fifo)->size) - 1;	\
161 	__init_fifo(fifo, gfp);						\
162 })
163 
164 #define free_fifo(fifo)							\
165 do {									\
166 	if (is_vmalloc_addr((fifo)->data))				\
167 		vfree((fifo)->data);					\
168 	else								\
169 		kfree((fifo)->data);					\
170 	(fifo)->data = NULL;						\
171 } while (0)
172 
173 #define fifo_used(fifo)		(((fifo)->back - (fifo)->front) & (fifo)->mask)
174 #define fifo_free(fifo)		((fifo)->size - fifo_used(fifo))
175 
176 #define fifo_empty(fifo)	(!fifo_used(fifo))
177 #define fifo_full(fifo)		(!fifo_free(fifo))
178 
179 #define fifo_front(fifo)	((fifo)->data[(fifo)->front])
180 #define fifo_back(fifo)							\
181 	((fifo)->data[((fifo)->back - 1) & (fifo)->mask])
182 
183 #define fifo_idx(fifo, p)	(((p) - &fifo_front(fifo)) & (fifo)->mask)
184 
185 #define fifo_push_back(fifo, i)						\
186 ({									\
187 	bool _r = !fifo_full((fifo));					\
188 	if (_r) {							\
189 		(fifo)->data[(fifo)->back++] = (i);			\
190 		(fifo)->back &= (fifo)->mask;				\
191 	}								\
192 	_r;								\
193 })
194 
195 #define fifo_pop_front(fifo, i)						\
196 ({									\
197 	bool _r = !fifo_empty((fifo));					\
198 	if (_r) {							\
199 		(i) = (fifo)->data[(fifo)->front++];			\
200 		(fifo)->front &= (fifo)->mask;				\
201 	}								\
202 	_r;								\
203 })
204 
205 #define fifo_push_front(fifo, i)					\
206 ({									\
207 	bool _r = !fifo_full((fifo));					\
208 	if (_r) {							\
209 		--(fifo)->front;					\
210 		(fifo)->front &= (fifo)->mask;				\
211 		(fifo)->data[(fifo)->front] = (i);			\
212 	}								\
213 	_r;								\
214 })
215 
216 #define fifo_pop_back(fifo, i)						\
217 ({									\
218 	bool _r = !fifo_empty((fifo));					\
219 	if (_r) {							\
220 		--(fifo)->back;						\
221 		(fifo)->back &= (fifo)->mask;				\
222 		(i) = (fifo)->data[(fifo)->back]			\
223 	}								\
224 	_r;								\
225 })
226 
227 #define fifo_push(fifo, i)	fifo_push_back(fifo, (i))
228 #define fifo_pop(fifo, i)	fifo_pop_front(fifo, (i))
229 
230 #define fifo_swap(l, r)							\
231 do {									\
232 	swap((l)->front, (r)->front);					\
233 	swap((l)->back, (r)->back);					\
234 	swap((l)->size, (r)->size);					\
235 	swap((l)->mask, (r)->mask);					\
236 	swap((l)->data, (r)->data);					\
237 } while (0)
238 
239 #define fifo_move(dest, src)						\
240 do {									\
241 	typeof(*((dest)->data)) _t;					\
242 	while (!fifo_full(dest) &&					\
243 	       fifo_pop(src, _t))					\
244 		fifo_push(dest, _t);					\
245 } while (0)
246 
247 /*
248  * Simple array based allocator - preallocates a number of elements and you can
249  * never allocate more than that, also has no locking.
250  *
251  * Handy because if you know you only need a fixed number of elements you don't
252  * have to worry about memory allocation failure, and sometimes a mempool isn't
253  * what you want.
254  *
255  * We treat the free elements as entries in a singly linked list, and the
256  * freelist as a stack - allocating and freeing push and pop off the freelist.
257  */
258 
259 #define DECLARE_ARRAY_ALLOCATOR(type, name, size)			\
260 	struct {							\
261 		type	*freelist;					\
262 		type	data[size];					\
263 	} name
264 
265 #define array_alloc(array)						\
266 ({									\
267 	typeof((array)->freelist) _ret = (array)->freelist;		\
268 									\
269 	if (_ret)							\
270 		(array)->freelist = *((typeof((array)->freelist) *) _ret);\
271 									\
272 	_ret;								\
273 })
274 
275 #define array_free(array, ptr)						\
276 do {									\
277 	typeof((array)->freelist) _ptr = ptr;				\
278 									\
279 	*((typeof((array)->freelist) *) _ptr) = (array)->freelist;	\
280 	(array)->freelist = _ptr;					\
281 } while (0)
282 
283 #define array_allocator_init(array)					\
284 do {									\
285 	typeof((array)->freelist) _i;					\
286 									\
287 	BUILD_BUG_ON(sizeof((array)->data[0]) < sizeof(void *));	\
288 	(array)->freelist = NULL;					\
289 									\
290 	for (_i = (array)->data;					\
291 	     _i < (array)->data + ARRAY_SIZE((array)->data);		\
292 	     _i++)							\
293 		array_free(array, _i);					\
294 } while (0)
295 
296 #define array_freelist_empty(array)	((array)->freelist == NULL)
297 
298 #define ANYSINT_MAX(t)							\
299 	((((t) 1 << (sizeof(t) * 8 - 2)) - (t) 1) * (t) 2 + (t) 1)
300 
301 int bch_strtoint_h(const char *, int *);
302 int bch_strtouint_h(const char *, unsigned int *);
303 int bch_strtoll_h(const char *, long long *);
304 int bch_strtoull_h(const char *, unsigned long long *);
305 
306 static inline int bch_strtol_h(const char *cp, long *res)
307 {
308 #if BITS_PER_LONG == 32
309 	return bch_strtoint_h(cp, (int *) res);
310 #else
311 	return bch_strtoll_h(cp, (long long *) res);
312 #endif
313 }
314 
315 static inline int bch_strtoul_h(const char *cp, long *res)
316 {
317 #if BITS_PER_LONG == 32
318 	return bch_strtouint_h(cp, (unsigned int *) res);
319 #else
320 	return bch_strtoull_h(cp, (unsigned long long *) res);
321 #endif
322 }
323 
324 #define strtoi_h(cp, res)						\
325 	(__builtin_types_compatible_p(typeof(*res), int)		\
326 	? bch_strtoint_h(cp, (void *) res)				\
327 	: __builtin_types_compatible_p(typeof(*res), long)		\
328 	? bch_strtol_h(cp, (void *) res)				\
329 	: __builtin_types_compatible_p(typeof(*res), long long)		\
330 	? bch_strtoll_h(cp, (void *) res)				\
331 	: __builtin_types_compatible_p(typeof(*res), unsigned int)	\
332 	? bch_strtouint_h(cp, (void *) res)				\
333 	: __builtin_types_compatible_p(typeof(*res), unsigned long)	\
334 	? bch_strtoul_h(cp, (void *) res)				\
335 	: __builtin_types_compatible_p(typeof(*res), unsigned long long)\
336 	? bch_strtoull_h(cp, (void *) res) : -EINVAL)
337 
338 #define strtoul_safe(cp, var)						\
339 ({									\
340 	unsigned long _v;						\
341 	int _r = kstrtoul(cp, 10, &_v);					\
342 	if (!_r)							\
343 		var = _v;						\
344 	_r;								\
345 })
346 
347 #define strtoul_safe_clamp(cp, var, min, max)				\
348 ({									\
349 	unsigned long _v;						\
350 	int _r = kstrtoul(cp, 10, &_v);					\
351 	if (!_r)							\
352 		var = clamp_t(typeof(var), _v, min, max);		\
353 	_r;								\
354 })
355 
356 #define snprint(buf, size, var)						\
357 	snprintf(buf, size,						\
358 		__builtin_types_compatible_p(typeof(var), int)		\
359 		     ? "%i\n" :						\
360 		__builtin_types_compatible_p(typeof(var), unsigned)	\
361 		     ? "%u\n" :						\
362 		__builtin_types_compatible_p(typeof(var), long)		\
363 		     ? "%li\n" :					\
364 		__builtin_types_compatible_p(typeof(var), unsigned long)\
365 		     ? "%lu\n" :					\
366 		__builtin_types_compatible_p(typeof(var), int64_t)	\
367 		     ? "%lli\n" :					\
368 		__builtin_types_compatible_p(typeof(var), uint64_t)	\
369 		     ? "%llu\n" :					\
370 		__builtin_types_compatible_p(typeof(var), const char *)	\
371 		     ? "%s\n" : "%i\n", var)
372 
373 ssize_t bch_hprint(char *buf, int64_t v);
374 
375 bool bch_is_zero(const char *p, size_t n);
376 int bch_parse_uuid(const char *s, char *uuid);
377 
378 ssize_t bch_snprint_string_list(char *buf, size_t size, const char * const list[],
379 			    size_t selected);
380 
381 ssize_t bch_read_string_list(const char *buf, const char * const list[]);
382 
383 struct time_stats {
384 	spinlock_t	lock;
385 	/*
386 	 * all fields are in nanoseconds, averages are ewmas stored left shifted
387 	 * by 8
388 	 */
389 	uint64_t	max_duration;
390 	uint64_t	average_duration;
391 	uint64_t	average_frequency;
392 	uint64_t	last;
393 };
394 
395 void bch_time_stats_update(struct time_stats *stats, uint64_t time);
396 
397 static inline unsigned local_clock_us(void)
398 {
399 	return local_clock() >> 10;
400 }
401 
402 #define NSEC_PER_ns			1L
403 #define NSEC_PER_us			NSEC_PER_USEC
404 #define NSEC_PER_ms			NSEC_PER_MSEC
405 #define NSEC_PER_sec			NSEC_PER_SEC
406 
407 #define __print_time_stat(stats, name, stat, units)			\
408 	sysfs_print(name ## _ ## stat ## _ ## units,			\
409 		    div_u64((stats)->stat >> 8, NSEC_PER_ ## units))
410 
411 #define sysfs_print_time_stats(stats, name,				\
412 			       frequency_units,				\
413 			       duration_units)				\
414 do {									\
415 	__print_time_stat(stats, name,					\
416 			  average_frequency,	frequency_units);	\
417 	__print_time_stat(stats, name,					\
418 			  average_duration,	duration_units);	\
419 	__print_time_stat(stats, name,					\
420 			  max_duration,		duration_units);	\
421 									\
422 	sysfs_print(name ## _last_ ## frequency_units, (stats)->last	\
423 		    ? div_s64(local_clock() - (stats)->last,		\
424 			      NSEC_PER_ ## frequency_units)		\
425 		    : -1LL);						\
426 } while (0)
427 
428 #define sysfs_time_stats_attribute(name,				\
429 				   frequency_units,			\
430 				   duration_units)			\
431 read_attribute(name ## _average_frequency_ ## frequency_units);		\
432 read_attribute(name ## _average_duration_ ## duration_units);		\
433 read_attribute(name ## _max_duration_ ## duration_units);		\
434 read_attribute(name ## _last_ ## frequency_units)
435 
436 #define sysfs_time_stats_attribute_list(name,				\
437 					frequency_units,		\
438 					duration_units)			\
439 &sysfs_ ## name ## _average_frequency_ ## frequency_units,		\
440 &sysfs_ ## name ## _average_duration_ ## duration_units,		\
441 &sysfs_ ## name ## _max_duration_ ## duration_units,			\
442 &sysfs_ ## name ## _last_ ## frequency_units,
443 
444 #define ewma_add(ewma, val, weight, factor)				\
445 ({									\
446 	(ewma) *= (weight) - 1;						\
447 	(ewma) += (val) << factor;					\
448 	(ewma) /= (weight);						\
449 	(ewma) >> factor;						\
450 })
451 
452 struct bch_ratelimit {
453 	/* Next time we want to do some work, in nanoseconds */
454 	uint64_t		next;
455 
456 	/*
457 	 * Rate at which we want to do work, in units per nanosecond
458 	 * The units here correspond to the units passed to bch_next_delay()
459 	 */
460 	unsigned		rate;
461 };
462 
463 static inline void bch_ratelimit_reset(struct bch_ratelimit *d)
464 {
465 	d->next = local_clock();
466 }
467 
468 uint64_t bch_next_delay(struct bch_ratelimit *d, uint64_t done);
469 
470 #define __DIV_SAFE(n, d, zero)						\
471 ({									\
472 	typeof(n) _n = (n);						\
473 	typeof(d) _d = (d);						\
474 	_d ? _n / _d : zero;						\
475 })
476 
477 #define DIV_SAFE(n, d)	__DIV_SAFE(n, d, 0)
478 
479 #define container_of_or_null(ptr, type, member)				\
480 ({									\
481 	typeof(ptr) _ptr = ptr;						\
482 	_ptr ? container_of(_ptr, type, member) : NULL;			\
483 })
484 
485 #define RB_INSERT(root, new, member, cmp)				\
486 ({									\
487 	__label__ dup;							\
488 	struct rb_node **n = &(root)->rb_node, *parent = NULL;		\
489 	typeof(new) this;						\
490 	int res, ret = -1;						\
491 									\
492 	while (*n) {							\
493 		parent = *n;						\
494 		this = container_of(*n, typeof(*(new)), member);	\
495 		res = cmp(new, this);					\
496 		if (!res)						\
497 			goto dup;					\
498 		n = res < 0						\
499 			? &(*n)->rb_left				\
500 			: &(*n)->rb_right;				\
501 	}								\
502 									\
503 	rb_link_node(&(new)->member, parent, n);			\
504 	rb_insert_color(&(new)->member, root);				\
505 	ret = 0;							\
506 dup:									\
507 	ret;								\
508 })
509 
510 #define RB_SEARCH(root, search, member, cmp)				\
511 ({									\
512 	struct rb_node *n = (root)->rb_node;				\
513 	typeof(&(search)) this, ret = NULL;				\
514 	int res;							\
515 									\
516 	while (n) {							\
517 		this = container_of(n, typeof(search), member);		\
518 		res = cmp(&(search), this);				\
519 		if (!res) {						\
520 			ret = this;					\
521 			break;						\
522 		}							\
523 		n = res < 0						\
524 			? n->rb_left					\
525 			: n->rb_right;					\
526 	}								\
527 	ret;								\
528 })
529 
530 #define RB_GREATER(root, search, member, cmp)				\
531 ({									\
532 	struct rb_node *n = (root)->rb_node;				\
533 	typeof(&(search)) this, ret = NULL;				\
534 	int res;							\
535 									\
536 	while (n) {							\
537 		this = container_of(n, typeof(search), member);		\
538 		res = cmp(&(search), this);				\
539 		if (res < 0) {						\
540 			ret = this;					\
541 			n = n->rb_left;					\
542 		} else							\
543 			n = n->rb_right;				\
544 	}								\
545 	ret;								\
546 })
547 
548 #define RB_FIRST(root, type, member)					\
549 	container_of_or_null(rb_first(root), type, member)
550 
551 #define RB_LAST(root, type, member)					\
552 	container_of_or_null(rb_last(root), type, member)
553 
554 #define RB_NEXT(ptr, member)						\
555 	container_of_or_null(rb_next(&(ptr)->member), typeof(*ptr), member)
556 
557 #define RB_PREV(ptr, member)						\
558 	container_of_or_null(rb_prev(&(ptr)->member), typeof(*ptr), member)
559 
560 /* Does linear interpolation between powers of two */
561 static inline unsigned fract_exp_two(unsigned x, unsigned fract_bits)
562 {
563 	unsigned fract = x & ~(~0 << fract_bits);
564 
565 	x >>= fract_bits;
566 	x   = 1 << x;
567 	x  += (x * fract) >> fract_bits;
568 
569 	return x;
570 }
571 
572 void bch_bio_map(struct bio *bio, void *base);
573 
574 static inline sector_t bdev_sectors(struct block_device *bdev)
575 {
576 	return bdev->bd_inode->i_size >> 9;
577 }
578 
579 #define closure_bio_submit(bio, cl, dev)				\
580 do {									\
581 	closure_get(cl);						\
582 	bch_generic_make_request(bio, &(dev)->bio_split_hook);		\
583 } while (0)
584 
585 uint64_t bch_crc64_update(uint64_t, const void *, size_t);
586 uint64_t bch_crc64(const void *, size_t);
587 
588 #endif /* _BCACHE_UTIL_H */
589