xref: /linux/drivers/md/bcache/util.h (revision c0e297dc61f8d4453e07afbea1fa8d0e67cd4a34)
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 	kvfree((heap)->data);						\
56 	(heap)->data = NULL;						\
57 } while (0)
58 
59 #define heap_swap(h, i, j)	swap((h)->data[i], (h)->data[j])
60 
61 #define heap_sift(h, i, cmp)						\
62 do {									\
63 	size_t _r, _j = i;						\
64 									\
65 	for (; _j * 2 + 1 < (h)->used; _j = _r) {			\
66 		_r = _j * 2 + 1;					\
67 		if (_r + 1 < (h)->used &&				\
68 		    cmp((h)->data[_r], (h)->data[_r + 1]))		\
69 			_r++;						\
70 									\
71 		if (cmp((h)->data[_r], (h)->data[_j]))			\
72 			break;						\
73 		heap_swap(h, _r, _j);					\
74 	}								\
75 } while (0)
76 
77 #define heap_sift_down(h, i, cmp)					\
78 do {									\
79 	while (i) {							\
80 		size_t p = (i - 1) / 2;					\
81 		if (cmp((h)->data[i], (h)->data[p]))			\
82 			break;						\
83 		heap_swap(h, i, p);					\
84 		i = p;							\
85 	}								\
86 } while (0)
87 
88 #define heap_add(h, d, cmp)						\
89 ({									\
90 	bool _r = !heap_full(h);					\
91 	if (_r) {							\
92 		size_t _i = (h)->used++;				\
93 		(h)->data[_i] = d;					\
94 									\
95 		heap_sift_down(h, _i, cmp);				\
96 		heap_sift(h, _i, cmp);					\
97 	}								\
98 	_r;								\
99 })
100 
101 #define heap_pop(h, d, cmp)						\
102 ({									\
103 	bool _r = (h)->used;						\
104 	if (_r) {							\
105 		(d) = (h)->data[0];					\
106 		(h)->used--;						\
107 		heap_swap(h, 0, (h)->used);				\
108 		heap_sift(h, 0, cmp);					\
109 	}								\
110 	_r;								\
111 })
112 
113 #define heap_peek(h)	((h)->used ? (h)->data[0] : NULL)
114 
115 #define heap_full(h)	((h)->used == (h)->size)
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 	(fifo)->data = NULL;						\
139 									\
140 	if (_bytes < KMALLOC_MAX_SIZE)					\
141 		(fifo)->data = kmalloc(_bytes, (gfp));			\
142 	if ((!(fifo)->data) && ((gfp) & GFP_KERNEL))			\
143 		(fifo)->data = vmalloc(_bytes);				\
144 	(fifo)->data;							\
145 })
146 
147 #define init_fifo_exact(fifo, _size, gfp)				\
148 ({									\
149 	(fifo)->size = (_size);						\
150 	__init_fifo(fifo, gfp);						\
151 })
152 
153 #define init_fifo(fifo, _size, gfp)					\
154 ({									\
155 	(fifo)->size = (_size);						\
156 	if ((fifo)->size > 4)						\
157 		(fifo)->size = roundup_pow_of_two((fifo)->size) - 1;	\
158 	__init_fifo(fifo, gfp);						\
159 })
160 
161 #define free_fifo(fifo)							\
162 do {									\
163 	kvfree((fifo)->data);						\
164 	(fifo)->data = NULL;						\
165 } while (0)
166 
167 #define fifo_used(fifo)		(((fifo)->back - (fifo)->front) & (fifo)->mask)
168 #define fifo_free(fifo)		((fifo)->size - fifo_used(fifo))
169 
170 #define fifo_empty(fifo)	(!fifo_used(fifo))
171 #define fifo_full(fifo)		(!fifo_free(fifo))
172 
173 #define fifo_front(fifo)	((fifo)->data[(fifo)->front])
174 #define fifo_back(fifo)							\
175 	((fifo)->data[((fifo)->back - 1) & (fifo)->mask])
176 
177 #define fifo_idx(fifo, p)	(((p) - &fifo_front(fifo)) & (fifo)->mask)
178 
179 #define fifo_push_back(fifo, i)						\
180 ({									\
181 	bool _r = !fifo_full((fifo));					\
182 	if (_r) {							\
183 		(fifo)->data[(fifo)->back++] = (i);			\
184 		(fifo)->back &= (fifo)->mask;				\
185 	}								\
186 	_r;								\
187 })
188 
189 #define fifo_pop_front(fifo, i)						\
190 ({									\
191 	bool _r = !fifo_empty((fifo));					\
192 	if (_r) {							\
193 		(i) = (fifo)->data[(fifo)->front++];			\
194 		(fifo)->front &= (fifo)->mask;				\
195 	}								\
196 	_r;								\
197 })
198 
199 #define fifo_push_front(fifo, i)					\
200 ({									\
201 	bool _r = !fifo_full((fifo));					\
202 	if (_r) {							\
203 		--(fifo)->front;					\
204 		(fifo)->front &= (fifo)->mask;				\
205 		(fifo)->data[(fifo)->front] = (i);			\
206 	}								\
207 	_r;								\
208 })
209 
210 #define fifo_pop_back(fifo, i)						\
211 ({									\
212 	bool _r = !fifo_empty((fifo));					\
213 	if (_r) {							\
214 		--(fifo)->back;						\
215 		(fifo)->back &= (fifo)->mask;				\
216 		(i) = (fifo)->data[(fifo)->back]			\
217 	}								\
218 	_r;								\
219 })
220 
221 #define fifo_push(fifo, i)	fifo_push_back(fifo, (i))
222 #define fifo_pop(fifo, i)	fifo_pop_front(fifo, (i))
223 
224 #define fifo_swap(l, r)							\
225 do {									\
226 	swap((l)->front, (r)->front);					\
227 	swap((l)->back, (r)->back);					\
228 	swap((l)->size, (r)->size);					\
229 	swap((l)->mask, (r)->mask);					\
230 	swap((l)->data, (r)->data);					\
231 } while (0)
232 
233 #define fifo_move(dest, src)						\
234 do {									\
235 	typeof(*((dest)->data)) _t;					\
236 	while (!fifo_full(dest) &&					\
237 	       fifo_pop(src, _t))					\
238 		fifo_push(dest, _t);					\
239 } while (0)
240 
241 /*
242  * Simple array based allocator - preallocates a number of elements and you can
243  * never allocate more than that, also has no locking.
244  *
245  * Handy because if you know you only need a fixed number of elements you don't
246  * have to worry about memory allocation failure, and sometimes a mempool isn't
247  * what you want.
248  *
249  * We treat the free elements as entries in a singly linked list, and the
250  * freelist as a stack - allocating and freeing push and pop off the freelist.
251  */
252 
253 #define DECLARE_ARRAY_ALLOCATOR(type, name, size)			\
254 	struct {							\
255 		type	*freelist;					\
256 		type	data[size];					\
257 	} name
258 
259 #define array_alloc(array)						\
260 ({									\
261 	typeof((array)->freelist) _ret = (array)->freelist;		\
262 									\
263 	if (_ret)							\
264 		(array)->freelist = *((typeof((array)->freelist) *) _ret);\
265 									\
266 	_ret;								\
267 })
268 
269 #define array_free(array, ptr)						\
270 do {									\
271 	typeof((array)->freelist) _ptr = ptr;				\
272 									\
273 	*((typeof((array)->freelist) *) _ptr) = (array)->freelist;	\
274 	(array)->freelist = _ptr;					\
275 } while (0)
276 
277 #define array_allocator_init(array)					\
278 do {									\
279 	typeof((array)->freelist) _i;					\
280 									\
281 	BUILD_BUG_ON(sizeof((array)->data[0]) < sizeof(void *));	\
282 	(array)->freelist = NULL;					\
283 									\
284 	for (_i = (array)->data;					\
285 	     _i < (array)->data + ARRAY_SIZE((array)->data);		\
286 	     _i++)							\
287 		array_free(array, _i);					\
288 } while (0)
289 
290 #define array_freelist_empty(array)	((array)->freelist == NULL)
291 
292 #define ANYSINT_MAX(t)							\
293 	((((t) 1 << (sizeof(t) * 8 - 2)) - (t) 1) * (t) 2 + (t) 1)
294 
295 int bch_strtoint_h(const char *, int *);
296 int bch_strtouint_h(const char *, unsigned int *);
297 int bch_strtoll_h(const char *, long long *);
298 int bch_strtoull_h(const char *, unsigned long long *);
299 
300 static inline int bch_strtol_h(const char *cp, long *res)
301 {
302 #if BITS_PER_LONG == 32
303 	return bch_strtoint_h(cp, (int *) res);
304 #else
305 	return bch_strtoll_h(cp, (long long *) res);
306 #endif
307 }
308 
309 static inline int bch_strtoul_h(const char *cp, long *res)
310 {
311 #if BITS_PER_LONG == 32
312 	return bch_strtouint_h(cp, (unsigned int *) res);
313 #else
314 	return bch_strtoull_h(cp, (unsigned long long *) res);
315 #endif
316 }
317 
318 #define strtoi_h(cp, res)						\
319 	(__builtin_types_compatible_p(typeof(*res), int)		\
320 	? bch_strtoint_h(cp, (void *) res)				\
321 	: __builtin_types_compatible_p(typeof(*res), long)		\
322 	? bch_strtol_h(cp, (void *) res)				\
323 	: __builtin_types_compatible_p(typeof(*res), long long)		\
324 	? bch_strtoll_h(cp, (void *) res)				\
325 	: __builtin_types_compatible_p(typeof(*res), unsigned int)	\
326 	? bch_strtouint_h(cp, (void *) res)				\
327 	: __builtin_types_compatible_p(typeof(*res), unsigned long)	\
328 	? bch_strtoul_h(cp, (void *) res)				\
329 	: __builtin_types_compatible_p(typeof(*res), unsigned long long)\
330 	? bch_strtoull_h(cp, (void *) res) : -EINVAL)
331 
332 #define strtoul_safe(cp, var)						\
333 ({									\
334 	unsigned long _v;						\
335 	int _r = kstrtoul(cp, 10, &_v);					\
336 	if (!_r)							\
337 		var = _v;						\
338 	_r;								\
339 })
340 
341 #define strtoul_safe_clamp(cp, var, min, max)				\
342 ({									\
343 	unsigned long _v;						\
344 	int _r = kstrtoul(cp, 10, &_v);					\
345 	if (!_r)							\
346 		var = clamp_t(typeof(var), _v, min, max);		\
347 	_r;								\
348 })
349 
350 #define snprint(buf, size, var)						\
351 	snprintf(buf, size,						\
352 		__builtin_types_compatible_p(typeof(var), int)		\
353 		     ? "%i\n" :						\
354 		__builtin_types_compatible_p(typeof(var), unsigned)	\
355 		     ? "%u\n" :						\
356 		__builtin_types_compatible_p(typeof(var), long)		\
357 		     ? "%li\n" :					\
358 		__builtin_types_compatible_p(typeof(var), unsigned long)\
359 		     ? "%lu\n" :					\
360 		__builtin_types_compatible_p(typeof(var), int64_t)	\
361 		     ? "%lli\n" :					\
362 		__builtin_types_compatible_p(typeof(var), uint64_t)	\
363 		     ? "%llu\n" :					\
364 		__builtin_types_compatible_p(typeof(var), const char *)	\
365 		     ? "%s\n" : "%i\n", var)
366 
367 ssize_t bch_hprint(char *buf, int64_t v);
368 
369 bool bch_is_zero(const char *p, size_t n);
370 int bch_parse_uuid(const char *s, char *uuid);
371 
372 ssize_t bch_snprint_string_list(char *buf, size_t size, const char * const list[],
373 			    size_t selected);
374 
375 ssize_t bch_read_string_list(const char *buf, const char * const list[]);
376 
377 struct time_stats {
378 	spinlock_t	lock;
379 	/*
380 	 * all fields are in nanoseconds, averages are ewmas stored left shifted
381 	 * by 8
382 	 */
383 	uint64_t	max_duration;
384 	uint64_t	average_duration;
385 	uint64_t	average_frequency;
386 	uint64_t	last;
387 };
388 
389 void bch_time_stats_update(struct time_stats *stats, uint64_t time);
390 
391 static inline unsigned local_clock_us(void)
392 {
393 	return local_clock() >> 10;
394 }
395 
396 #define NSEC_PER_ns			1L
397 #define NSEC_PER_us			NSEC_PER_USEC
398 #define NSEC_PER_ms			NSEC_PER_MSEC
399 #define NSEC_PER_sec			NSEC_PER_SEC
400 
401 #define __print_time_stat(stats, name, stat, units)			\
402 	sysfs_print(name ## _ ## stat ## _ ## units,			\
403 		    div_u64((stats)->stat >> 8, NSEC_PER_ ## units))
404 
405 #define sysfs_print_time_stats(stats, name,				\
406 			       frequency_units,				\
407 			       duration_units)				\
408 do {									\
409 	__print_time_stat(stats, name,					\
410 			  average_frequency,	frequency_units);	\
411 	__print_time_stat(stats, name,					\
412 			  average_duration,	duration_units);	\
413 	sysfs_print(name ## _ ##max_duration ## _ ## duration_units,	\
414 			div_u64((stats)->max_duration, NSEC_PER_ ## duration_units));\
415 									\
416 	sysfs_print(name ## _last_ ## frequency_units, (stats)->last	\
417 		    ? div_s64(local_clock() - (stats)->last,		\
418 			      NSEC_PER_ ## frequency_units)		\
419 		    : -1LL);						\
420 } while (0)
421 
422 #define sysfs_time_stats_attribute(name,				\
423 				   frequency_units,			\
424 				   duration_units)			\
425 read_attribute(name ## _average_frequency_ ## frequency_units);		\
426 read_attribute(name ## _average_duration_ ## duration_units);		\
427 read_attribute(name ## _max_duration_ ## duration_units);		\
428 read_attribute(name ## _last_ ## frequency_units)
429 
430 #define sysfs_time_stats_attribute_list(name,				\
431 					frequency_units,		\
432 					duration_units)			\
433 &sysfs_ ## name ## _average_frequency_ ## frequency_units,		\
434 &sysfs_ ## name ## _average_duration_ ## duration_units,		\
435 &sysfs_ ## name ## _max_duration_ ## duration_units,			\
436 &sysfs_ ## name ## _last_ ## frequency_units,
437 
438 #define ewma_add(ewma, val, weight, factor)				\
439 ({									\
440 	(ewma) *= (weight) - 1;						\
441 	(ewma) += (val) << factor;					\
442 	(ewma) /= (weight);						\
443 	(ewma) >> factor;						\
444 })
445 
446 struct bch_ratelimit {
447 	/* Next time we want to do some work, in nanoseconds */
448 	uint64_t		next;
449 
450 	/*
451 	 * Rate at which we want to do work, in units per nanosecond
452 	 * The units here correspond to the units passed to bch_next_delay()
453 	 */
454 	unsigned		rate;
455 };
456 
457 static inline void bch_ratelimit_reset(struct bch_ratelimit *d)
458 {
459 	d->next = local_clock();
460 }
461 
462 uint64_t bch_next_delay(struct bch_ratelimit *d, uint64_t done);
463 
464 #define __DIV_SAFE(n, d, zero)						\
465 ({									\
466 	typeof(n) _n = (n);						\
467 	typeof(d) _d = (d);						\
468 	_d ? _n / _d : zero;						\
469 })
470 
471 #define DIV_SAFE(n, d)	__DIV_SAFE(n, d, 0)
472 
473 #define container_of_or_null(ptr, type, member)				\
474 ({									\
475 	typeof(ptr) _ptr = ptr;						\
476 	_ptr ? container_of(_ptr, type, member) : NULL;			\
477 })
478 
479 #define RB_INSERT(root, new, member, cmp)				\
480 ({									\
481 	__label__ dup;							\
482 	struct rb_node **n = &(root)->rb_node, *parent = NULL;		\
483 	typeof(new) this;						\
484 	int res, ret = -1;						\
485 									\
486 	while (*n) {							\
487 		parent = *n;						\
488 		this = container_of(*n, typeof(*(new)), member);	\
489 		res = cmp(new, this);					\
490 		if (!res)						\
491 			goto dup;					\
492 		n = res < 0						\
493 			? &(*n)->rb_left				\
494 			: &(*n)->rb_right;				\
495 	}								\
496 									\
497 	rb_link_node(&(new)->member, parent, n);			\
498 	rb_insert_color(&(new)->member, root);				\
499 	ret = 0;							\
500 dup:									\
501 	ret;								\
502 })
503 
504 #define RB_SEARCH(root, search, member, cmp)				\
505 ({									\
506 	struct rb_node *n = (root)->rb_node;				\
507 	typeof(&(search)) this, ret = NULL;				\
508 	int res;							\
509 									\
510 	while (n) {							\
511 		this = container_of(n, typeof(search), member);		\
512 		res = cmp(&(search), this);				\
513 		if (!res) {						\
514 			ret = this;					\
515 			break;						\
516 		}							\
517 		n = res < 0						\
518 			? n->rb_left					\
519 			: n->rb_right;					\
520 	}								\
521 	ret;								\
522 })
523 
524 #define RB_GREATER(root, search, member, cmp)				\
525 ({									\
526 	struct rb_node *n = (root)->rb_node;				\
527 	typeof(&(search)) this, ret = NULL;				\
528 	int res;							\
529 									\
530 	while (n) {							\
531 		this = container_of(n, typeof(search), member);		\
532 		res = cmp(&(search), this);				\
533 		if (res < 0) {						\
534 			ret = this;					\
535 			n = n->rb_left;					\
536 		} else							\
537 			n = n->rb_right;				\
538 	}								\
539 	ret;								\
540 })
541 
542 #define RB_FIRST(root, type, member)					\
543 	container_of_or_null(rb_first(root), type, member)
544 
545 #define RB_LAST(root, type, member)					\
546 	container_of_or_null(rb_last(root), type, member)
547 
548 #define RB_NEXT(ptr, member)						\
549 	container_of_or_null(rb_next(&(ptr)->member), typeof(*ptr), member)
550 
551 #define RB_PREV(ptr, member)						\
552 	container_of_or_null(rb_prev(&(ptr)->member), typeof(*ptr), member)
553 
554 /* Does linear interpolation between powers of two */
555 static inline unsigned fract_exp_two(unsigned x, unsigned fract_bits)
556 {
557 	unsigned fract = x & ~(~0 << fract_bits);
558 
559 	x >>= fract_bits;
560 	x   = 1 << x;
561 	x  += (x * fract) >> fract_bits;
562 
563 	return x;
564 }
565 
566 void bch_bio_map(struct bio *bio, void *base);
567 
568 static inline sector_t bdev_sectors(struct block_device *bdev)
569 {
570 	return bdev->bd_inode->i_size >> 9;
571 }
572 
573 #define closure_bio_submit(bio, cl, dev)				\
574 do {									\
575 	closure_get(cl);						\
576 	bch_generic_make_request(bio, &(dev)->bio_split_hook);		\
577 } while (0)
578 
579 uint64_t bch_crc64_update(uint64_t, const void *, size_t);
580 uint64_t bch_crc64(const void *, size_t);
581 
582 #endif /* _BCACHE_UTIL_H */
583