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| author | David Sterba <dsterba@suse.com> | 2019-10-01 19:40:15 +0200 |
|---|---|---|
| committer | David Sterba <dsterba@suse.com> | 2019-11-18 12:46:50 +0100 |
| commit | 79c8264e443471eb2748c93680acce54d14d2225 (patch) | |
| tree | 380f4761db1fe9933d8c3dfd84e4b5282c7a533c | |
| parent | e62869be1ed7569bf12a5dc28c5b7ee5823f9cf3 (diff) | |
btrfs: add 64bit safe helper for power of two checks
As is_power_of_two takes unsigned long, it's not safe on 32bit
architectures, but we could pass any u64 value in seveal places. Add a
separate helper and also an alias that better expresses the purpose for
which the helper is used.
Signed-off-by: David Sterba <dsterba@suse.com>
| -rw-r--r-- | fs/btrfs/misc.h | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/fs/btrfs/misc.h b/fs/btrfs/misc.h index 7d564924dfeb..72bab64ecf60 100644 --- a/fs/btrfs/misc.h +++ b/fs/btrfs/misc.h @@ -47,4 +47,15 @@ static inline u64 div_factor_fine(u64 num, int 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); +} + #endif |