1/* SPDX-License-Identifier: GPL-2.0 */
 2
 3#ifndef BTRFS_MISC_H
 4#define BTRFS_MISC_H
 5
 6#include <linux/sched.h>
 7#include <linux/wait.h>
 8#include <asm/div64.h>
 
 9
10#define in_range(b, first, len) ((b) >= (first) && (b) < (first) + (len))
11
12static inline void cond_wake_up(struct wait_queue_head *wq)
13{
14	/*
15	 * This implies a full smp_mb barrier, see comments for
16	 * waitqueue_active why.
17	 */
18	if (wq_has_sleeper(wq))
19		wake_up(wq);
20}
21
22static inline void cond_wake_up_nomb(struct wait_queue_head *wq)
23{
24	/*
25	 * Special case for conditional wakeup where the barrier required for
26	 * waitqueue_active is implied by some of the preceding code. Eg. one
27	 * of such atomic operations (atomic_dec_and_return, ...), or a
28	 * unlock/lock sequence, etc.
29	 */
30	if (waitqueue_active(wq))
31		wake_up(wq);
32}
33
34static inline u64 div_factor(u64 num, int factor)
35{
36	if (factor == 10)
37		return num;
38	num *= factor;
39	return div_u64(num, 10);
40}
41
42static inline u64 div_factor_fine(u64 num, int factor)
43{
44	if (factor == 100)
45		return num;
46	num *= factor;
47	return div_u64(num, 100);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
48}
49
50#endif

  1/* SPDX-License-Identifier: GPL-2.0 */
  2
  3#ifndef BTRFS_MISC_H
  4#define BTRFS_MISC_H
  5
  6#include <linux/sched.h>
  7#include <linux/wait.h>
  8#include <asm/div64.h>
  9#include <linux/rbtree.h>
 10
 11#define in_range(b, first, len) ((b) >= (first) && (b) < (first) + (len))
 12
 13static inline void cond_wake_up(struct wait_queue_head *wq)
 14{
 15	/*
 16	 * This implies a full smp_mb barrier, see comments for
 17	 * waitqueue_active why.
 18	 */
 19	if (wq_has_sleeper(wq))
 20		wake_up(wq);
 21}
 22
 23static inline void cond_wake_up_nomb(struct wait_queue_head *wq)
 24{
 25	/*
 26	 * Special case for conditional wakeup where the barrier required for
 27	 * waitqueue_active is implied by some of the preceding code. Eg. one
 28	 * of such atomic operations (atomic_dec_and_return, ...), or a
 29	 * unlock/lock sequence, etc.
 30	 */
 31	if (waitqueue_active(wq))
 32		wake_up(wq);
 33}
 34
 35static inline u64 div_factor(u64 num, int factor)
 36{
 37	if (factor == 10)
 38		return num;
 39	num *= factor;
 40	return div_u64(num, 10);
 41}
 42
 43static inline u64 div_factor_fine(u64 num, int factor)
 44{
 45	if (factor == 100)
 46		return num;
 47	num *= factor;
 48	return div_u64(num, 100);
 49}
 50
 51/* Copy of is_power_of_two that is 64bit safe */
 52static inline bool is_power_of_two_u64(u64 n)
 53{
 54	return n != 0 && (n & (n - 1)) == 0;
 55}
 56
 57static inline bool has_single_bit_set(u64 n)
 58{
 59	return is_power_of_two_u64(n);
 60}
 61
 62/*
 63 * Simple bytenr based rb_tree relate structures
 64 *
 65 * Any structure wants to use bytenr as single search index should have their
 66 * structure start with these members.
 67 */
 68struct rb_simple_node {
 69	struct rb_node rb_node;
 70	u64 bytenr;
 71};
 72
 73static inline struct rb_node *rb_simple_search(struct rb_root *root, u64 bytenr)
 74{
 75	struct rb_node *node = root->rb_node;
 76	struct rb_simple_node *entry;
 77
 78	while (node) {
 79		entry = rb_entry(node, struct rb_simple_node, rb_node);
 80
 81		if (bytenr < entry->bytenr)
 82			node = node->rb_left;
 83		else if (bytenr > entry->bytenr)
 84			node = node->rb_right;
 85		else
 86			return node;
 87	}
 88	return NULL;
 89}
 90
 91static inline struct rb_node *rb_simple_insert(struct rb_root *root, u64 bytenr,
 92					       struct rb_node *node)
 93{
 94	struct rb_node **p = &root->rb_node;
 95	struct rb_node *parent = NULL;
 96	struct rb_simple_node *entry;
 97
 98	while (*p) {
 99		parent = *p;
100		entry = rb_entry(parent, struct rb_simple_node, rb_node);
101
102		if (bytenr < entry->bytenr)
103			p = &(*p)->rb_left;
104		else if (bytenr > entry->bytenr)
105			p = &(*p)->rb_right;
106		else
107			return parent;
108	}
109
110	rb_link_node(node, parent, p);
111	rb_insert_color(node, root);
112	return NULL;
113}
114
115#endif