GNU Linux-libre 4.19.314-gnu1
[releases.git] / drivers / md / bcache / util.h
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 DECLARE_FIFO(type, name)                                        \
117         struct {                                                        \
118                 size_t front, back, size, mask;                         \
119                 type *data;                                             \
120         } name
121
122 #define fifo_for_each(c, fifo, iter)                                    \
123         for (iter = (fifo)->front;                                      \
124              c = (fifo)->data[iter], iter != (fifo)->back;              \
125              iter = (iter + 1) & (fifo)->mask)
126
127 #define __init_fifo(fifo, gfp)                                          \
128 ({                                                                      \
129         size_t _allocated_size, _bytes;                                 \
130         BUG_ON(!(fifo)->size);                                          \
131                                                                         \
132         _allocated_size = roundup_pow_of_two((fifo)->size + 1);         \
133         _bytes = _allocated_size * sizeof(*(fifo)->data);               \
134                                                                         \
135         (fifo)->mask = _allocated_size - 1;                             \
136         (fifo)->front = (fifo)->back = 0;                               \
137                                                                         \
138         (fifo)->data = kvmalloc(_bytes, (gfp) & GFP_KERNEL);            \
139         (fifo)->data;                                                   \
140 })
141
142 #define init_fifo_exact(fifo, _size, gfp)                               \
143 ({                                                                      \
144         (fifo)->size = (_size);                                         \
145         __init_fifo(fifo, gfp);                                         \
146 })
147
148 #define init_fifo(fifo, _size, gfp)                                     \
149 ({                                                                      \
150         (fifo)->size = (_size);                                         \
151         if ((fifo)->size > 4)                                           \
152                 (fifo)->size = roundup_pow_of_two((fifo)->size) - 1;    \
153         __init_fifo(fifo, gfp);                                         \
154 })
155
156 #define free_fifo(fifo)                                                 \
157 do {                                                                    \
158         kvfree((fifo)->data);                                           \
159         (fifo)->data = NULL;                                            \
160 } while (0)
161
162 #define fifo_used(fifo)         (((fifo)->back - (fifo)->front) & (fifo)->mask)
163 #define fifo_free(fifo)         ((fifo)->size - fifo_used(fifo))
164
165 #define fifo_empty(fifo)        (!fifo_used(fifo))
166 #define fifo_full(fifo)         (!fifo_free(fifo))
167
168 #define fifo_front(fifo)        ((fifo)->data[(fifo)->front])
169 #define fifo_back(fifo)                                                 \
170         ((fifo)->data[((fifo)->back - 1) & (fifo)->mask])
171
172 #define fifo_idx(fifo, p)       (((p) - &fifo_front(fifo)) & (fifo)->mask)
173
174 #define fifo_push_back(fifo, i)                                         \
175 ({                                                                      \
176         bool _r = !fifo_full((fifo));                                   \
177         if (_r) {                                                       \
178                 (fifo)->data[(fifo)->back++] = (i);                     \
179                 (fifo)->back &= (fifo)->mask;                           \
180         }                                                               \
181         _r;                                                             \
182 })
183
184 #define fifo_pop_front(fifo, i)                                         \
185 ({                                                                      \
186         bool _r = !fifo_empty((fifo));                                  \
187         if (_r) {                                                       \
188                 (i) = (fifo)->data[(fifo)->front++];                    \
189                 (fifo)->front &= (fifo)->mask;                          \
190         }                                                               \
191         _r;                                                             \
192 })
193
194 #define fifo_push_front(fifo, i)                                        \
195 ({                                                                      \
196         bool _r = !fifo_full((fifo));                                   \
197         if (_r) {                                                       \
198                 --(fifo)->front;                                        \
199                 (fifo)->front &= (fifo)->mask;                          \
200                 (fifo)->data[(fifo)->front] = (i);                      \
201         }                                                               \
202         _r;                                                             \
203 })
204
205 #define fifo_pop_back(fifo, i)                                          \
206 ({                                                                      \
207         bool _r = !fifo_empty((fifo));                                  \
208         if (_r) {                                                       \
209                 --(fifo)->back;                                         \
210                 (fifo)->back &= (fifo)->mask;                           \
211                 (i) = (fifo)->data[(fifo)->back]                        \
212         }                                                               \
213         _r;                                                             \
214 })
215
216 #define fifo_push(fifo, i)      fifo_push_back(fifo, (i))
217 #define fifo_pop(fifo, i)       fifo_pop_front(fifo, (i))
218
219 #define fifo_swap(l, r)                                                 \
220 do {                                                                    \
221         swap((l)->front, (r)->front);                                   \
222         swap((l)->back, (r)->back);                                     \
223         swap((l)->size, (r)->size);                                     \
224         swap((l)->mask, (r)->mask);                                     \
225         swap((l)->data, (r)->data);                                     \
226 } while (0)
227
228 #define fifo_move(dest, src)                                            \
229 do {                                                                    \
230         typeof(*((dest)->data)) _t;                                     \
231         while (!fifo_full(dest) &&                                      \
232                fifo_pop(src, _t))                                       \
233                 fifo_push(dest, _t);                                    \
234 } while (0)
235
236 /*
237  * Simple array based allocator - preallocates a number of elements and you can
238  * never allocate more than that, also has no locking.
239  *
240  * Handy because if you know you only need a fixed number of elements you don't
241  * have to worry about memory allocation failure, and sometimes a mempool isn't
242  * what you want.
243  *
244  * We treat the free elements as entries in a singly linked list, and the
245  * freelist as a stack - allocating and freeing push and pop off the freelist.
246  */
247
248 #define DECLARE_ARRAY_ALLOCATOR(type, name, size)                       \
249         struct {                                                        \
250                 type    *freelist;                                      \
251                 type    data[size];                                     \
252         } name
253
254 #define array_alloc(array)                                              \
255 ({                                                                      \
256         typeof((array)->freelist) _ret = (array)->freelist;             \
257                                                                         \
258         if (_ret)                                                       \
259                 (array)->freelist = *((typeof((array)->freelist) *) _ret);\
260                                                                         \
261         _ret;                                                           \
262 })
263
264 #define array_free(array, ptr)                                          \
265 do {                                                                    \
266         typeof((array)->freelist) _ptr = ptr;                           \
267                                                                         \
268         *((typeof((array)->freelist) *) _ptr) = (array)->freelist;      \
269         (array)->freelist = _ptr;                                       \
270 } while (0)
271
272 #define array_allocator_init(array)                                     \
273 do {                                                                    \
274         typeof((array)->freelist) _i;                                   \
275                                                                         \
276         BUILD_BUG_ON(sizeof((array)->data[0]) < sizeof(void *));        \
277         (array)->freelist = NULL;                                       \
278                                                                         \
279         for (_i = (array)->data;                                        \
280              _i < (array)->data + ARRAY_SIZE((array)->data);            \
281              _i++)                                                      \
282                 array_free(array, _i);                                  \
283 } while (0)
284
285 #define array_freelist_empty(array)     ((array)->freelist == NULL)
286
287 #define ANYSINT_MAX(t)                                                  \
288         ((((t) 1 << (sizeof(t) * 8 - 2)) - (t) 1) * (t) 2 + (t) 1)
289
290 int bch_strtoint_h(const char *cp, int *res);
291 int bch_strtouint_h(const char *cp, unsigned int *res);
292 int bch_strtoll_h(const char *cp, long long *res);
293 int bch_strtoull_h(const char *cp, unsigned long long *res);
294
295 static inline int bch_strtol_h(const char *cp, long *res)
296 {
297 #if BITS_PER_LONG == 32
298         return bch_strtoint_h(cp, (int *) res);
299 #else
300         return bch_strtoll_h(cp, (long long *) res);
301 #endif
302 }
303
304 static inline int bch_strtoul_h(const char *cp, long *res)
305 {
306 #if BITS_PER_LONG == 32
307         return bch_strtouint_h(cp, (unsigned int *) res);
308 #else
309         return bch_strtoull_h(cp, (unsigned long long *) res);
310 #endif
311 }
312
313 #define strtoi_h(cp, res)                                               \
314         (__builtin_types_compatible_p(typeof(*res), int)                \
315         ? bch_strtoint_h(cp, (void *) res)                              \
316         : __builtin_types_compatible_p(typeof(*res), long)              \
317         ? bch_strtol_h(cp, (void *) res)                                \
318         : __builtin_types_compatible_p(typeof(*res), long long)         \
319         ? bch_strtoll_h(cp, (void *) res)                               \
320         : __builtin_types_compatible_p(typeof(*res), unsigned int)      \
321         ? bch_strtouint_h(cp, (void *) res)                             \
322         : __builtin_types_compatible_p(typeof(*res), unsigned long)     \
323         ? bch_strtoul_h(cp, (void *) res)                               \
324         : __builtin_types_compatible_p(typeof(*res), unsigned long long)\
325         ? bch_strtoull_h(cp, (void *) res) : -EINVAL)
326
327 #define strtoul_safe(cp, var)                                           \
328 ({                                                                      \
329         unsigned long _v;                                               \
330         int _r = kstrtoul(cp, 10, &_v);                                 \
331         if (!_r)                                                        \
332                 var = _v;                                               \
333         _r;                                                             \
334 })
335
336 #define strtoul_safe_clamp(cp, var, min, max)                           \
337 ({                                                                      \
338         unsigned long _v;                                               \
339         int _r = kstrtoul(cp, 10, &_v);                                 \
340         if (!_r)                                                        \
341                 var = clamp_t(typeof(var), _v, min, max);               \
342         _r;                                                             \
343 })
344
345 #define snprint(buf, size, var)                                         \
346         snprintf(buf, size,                                             \
347                 __builtin_types_compatible_p(typeof(var), int)          \
348                      ? "%i\n" :                                         \
349                 __builtin_types_compatible_p(typeof(var), unsigned int) \
350                      ? "%u\n" :                                         \
351                 __builtin_types_compatible_p(typeof(var), long)         \
352                      ? "%li\n" :                                        \
353                 __builtin_types_compatible_p(typeof(var), unsigned long)\
354                      ? "%lu\n" :                                        \
355                 __builtin_types_compatible_p(typeof(var), int64_t)      \
356                      ? "%lli\n" :                                       \
357                 __builtin_types_compatible_p(typeof(var), uint64_t)     \
358                      ? "%llu\n" :                                       \
359                 __builtin_types_compatible_p(typeof(var), const char *) \
360                      ? "%s\n" : "%i\n", var)
361
362 ssize_t bch_hprint(char *buf, int64_t v);
363
364 bool bch_is_zero(const char *p, size_t n);
365 int bch_parse_uuid(const char *s, char *uuid);
366
367 struct time_stats {
368         spinlock_t      lock;
369         /*
370          * all fields are in nanoseconds, averages are ewmas stored left shifted
371          * by 8
372          */
373         uint64_t        max_duration;
374         uint64_t        average_duration;
375         uint64_t        average_frequency;
376         uint64_t        last;
377 };
378
379 void bch_time_stats_update(struct time_stats *stats, uint64_t time);
380
381 static inline unsigned int local_clock_us(void)
382 {
383         return local_clock() >> 10;
384 }
385
386 #define NSEC_PER_ns                     1L
387 #define NSEC_PER_us                     NSEC_PER_USEC
388 #define NSEC_PER_ms                     NSEC_PER_MSEC
389 #define NSEC_PER_sec                    NSEC_PER_SEC
390
391 #define __print_time_stat(stats, name, stat, units)                     \
392         sysfs_print(name ## _ ## stat ## _ ## units,                    \
393                     div_u64((stats)->stat >> 8, NSEC_PER_ ## units))
394
395 #define sysfs_print_time_stats(stats, name,                             \
396                                frequency_units,                         \
397                                duration_units)                          \
398 do {                                                                    \
399         __print_time_stat(stats, name,                                  \
400                           average_frequency,    frequency_units);       \
401         __print_time_stat(stats, name,                                  \
402                           average_duration,     duration_units);        \
403         sysfs_print(name ## _ ##max_duration ## _ ## duration_units,    \
404                         div_u64((stats)->max_duration,                  \
405                                 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         atomic_long_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 static inline uint64_t bch_crc64(const void *p, size_t len)
546 {
547         uint64_t crc = 0xffffffffffffffffULL;
548
549         crc = crc64_be(crc, p, len);
550         return crc ^ 0xffffffffffffffffULL;
551 }
552
553 static inline uint64_t bch_crc64_update(uint64_t crc,
554                                         const void *p,
555                                         size_t len)
556 {
557         crc = crc64_be(crc, p, len);
558         return crc;
559 }
560
561 /* Does linear interpolation between powers of two */
562 static inline unsigned int fract_exp_two(unsigned int x,
563                                          unsigned int fract_bits)
564 {
565         unsigned int fract = x & ~(~0 << fract_bits);
566
567         x >>= fract_bits;
568         x   = 1 << x;
569         x  += (x * fract) >> fract_bits;
570
571         return x;
572 }
573
574 void bch_bio_map(struct bio *bio, void *base);
575 int bch_bio_alloc_pages(struct bio *bio, gfp_t gfp_mask);
576
577 static inline sector_t bdev_sectors(struct block_device *bdev)
578 {
579         return bdev->bd_inode->i_size >> 9;
580 }
581 #endif /* _BCACHE_UTIL_H */