116 lines
2.4 KiB
C
116 lines
2.4 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
|
|
#ifndef BTRFS_MISC_H
|
|
#define BTRFS_MISC_H
|
|
|
|
#include <linux/sched.h>
|
|
#include <linux/wait.h>
|
|
#include <asm/div64.h>
|
|
#include <linux/rbtree.h>
|
|
|
|
#define in_range(b, first, len) ((b) >= (first) && (b) < (first) + (len))
|
|
|
|
static inline void cond_wake_up(struct wait_queue_head *wq)
|
|
{
|
|
/*
|
|
* This implies a full smp_mb barrier, see comments for
|
|
* waitqueue_active why.
|
|
*/
|
|
if (wq_has_sleeper(wq))
|
|
wake_up(wq);
|
|
}
|
|
|
|
static inline void cond_wake_up_nomb(struct wait_queue_head *wq)
|
|
{
|
|
/*
|
|
* Special case for conditional wakeup where the barrier required for
|
|
* waitqueue_active is implied by some of the preceding code. Eg. one
|
|
* of such atomic operations (atomic_dec_and_return, ...), or a
|
|
* unlock/lock sequence, etc.
|
|
*/
|
|
if (waitqueue_active(wq))
|
|
wake_up(wq);
|
|
}
|
|
|
|
static inline u64 div_factor(u64 num, int factor)
|
|
{
|
|
if (factor == 10)
|
|
return num;
|
|
num *= factor;
|
|
return div_u64(num, 10);
|
|
}
|
|
|
|
static inline u64 div_factor_fine(u64 num, int factor)
|
|
{
|
|
if (factor == 100)
|
|
return num;
|
|
num *= factor;
|
|
return div_u64(num, 100);
|
|
}
|
|
|
|
/* Copy of is_power_of_two that is 64bit safe */
|
|
static inline bool is_power_of_two_u64(u64 n)
|
|
{
|
|
return n != 0 && (n & (n - 1)) == 0;
|
|
}
|
|
|
|
static inline bool has_single_bit_set(u64 n)
|
|
{
|
|
return is_power_of_two_u64(n);
|
|
}
|
|
|
|
/*
|
|
* Simple bytenr based rb_tree relate structures
|
|
*
|
|
* Any structure wants to use bytenr as single search index should have their
|
|
* structure start with these members.
|
|
*/
|
|
struct rb_simple_node {
|
|
struct rb_node rb_node;
|
|
u64 bytenr;
|
|
};
|
|
|
|
static inline struct rb_node *rb_simple_search(struct rb_root *root, u64 bytenr)
|
|
{
|
|
struct rb_node *node = root->rb_node;
|
|
struct rb_simple_node *entry;
|
|
|
|
while (node) {
|
|
entry = rb_entry(node, struct rb_simple_node, rb_node);
|
|
|
|
if (bytenr < entry->bytenr)
|
|
node = node->rb_left;
|
|
else if (bytenr > entry->bytenr)
|
|
node = node->rb_right;
|
|
else
|
|
return node;
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
static inline struct rb_node *rb_simple_insert(struct rb_root *root, u64 bytenr,
|
|
struct rb_node *node)
|
|
{
|
|
struct rb_node **p = &root->rb_node;
|
|
struct rb_node *parent = NULL;
|
|
struct rb_simple_node *entry;
|
|
|
|
while (*p) {
|
|
parent = *p;
|
|
entry = rb_entry(parent, struct rb_simple_node, rb_node);
|
|
|
|
if (bytenr < entry->bytenr)
|
|
p = &(*p)->rb_left;
|
|
else if (bytenr > entry->bytenr)
|
|
p = &(*p)->rb_right;
|
|
else
|
|
return parent;
|
|
}
|
|
|
|
rb_link_node(node, parent, p);
|
|
rb_insert_color(node, root);
|
|
return NULL;
|
|
}
|
|
|
|
#endif
|