xref: /openbmc/linux/fs/btrfs/misc.h (revision 08283d30)
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 
12 static 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 
22 static 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 
34 static 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 
42 static 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
51