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
17struct 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)							\
54do {									\
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)						\
65do {									\
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)					\
81do {									\
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)							\
165do {									\
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)							\
231do {									\
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)						\
240do {									\
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)						\
276do {									\
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)					\
284do {									\
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
301int bch_strtoint_h(const char *, int *);
302int bch_strtouint_h(const char *, unsigned int *);
303int bch_strtoll_h(const char *, long long *);
304int bch_strtoull_h(const char *, unsigned long long *);
305
306static 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
315static 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
373ssize_t bch_hprint(char *buf, int64_t v);
374
375bool bch_is_zero(const char *p, size_t n);
376int bch_parse_uuid(const char *s, char *uuid);
377
378ssize_t bch_snprint_string_list(char *buf, size_t size, const char * const list[],
379			    size_t selected);
380
381ssize_t bch_read_string_list(const char *buf, const char * const list[]);
382
383struct 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
395void bch_time_stats_update(struct time_stats *stats, uint64_t time);
396
397static 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)				\
414do {									\
415	__print_time_stat(stats, name,					\
416			  average_frequency,	frequency_units);	\
417	__print_time_stat(stats, name,					\
418			  average_duration,	duration_units);	\
419	sysfs_print(name ## _ ##max_duration ## _ ## duration_units,	\
420			div_u64((stats)->max_duration, NSEC_PER_ ## 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)			\
431read_attribute(name ## _average_frequency_ ## frequency_units);		\
432read_attribute(name ## _average_duration_ ## duration_units);		\
433read_attribute(name ## _max_duration_ ## duration_units);		\
434read_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
452struct 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
463static inline void bch_ratelimit_reset(struct bch_ratelimit *d)
464{
465	d->next = local_clock();
466}
467
468uint64_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;							\
506dup:									\
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 */
561static 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
572void bch_bio_map(struct bio *bio, void *base);
573
574static 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)				\
580do {									\
581	closure_get(cl);						\
582	bch_generic_make_request(bio, &(dev)->bio_split_hook);		\
583} while (0)
584
585uint64_t bch_crc64_update(uint64_t, const void *, size_t);
586uint64_t bch_crc64(const void *, size_t);
587
588#endif /* _BCACHE_UTIL_H */
589