From: Zygo Blaxell ce3g8jdj@umail.furryterror.org
commit 7a54789074a54f64addf5b49bf1994f478337a83 upstream.
Currently, the command:
btrfs balance start -dconvert=single,soft .
on a Raspberry Pi produces the following kernel message:
BTRFS error (device mmcblk0p2): balance: invalid convert data profile single
This fails because we use is_power_of_2(unsigned long) to validate the new data profile, the constant for 'single' profile uses bit 48, and there are only 32 bits in a long on ARM.
Fix by open-coding the check using u64 variables.
Tested by completing the original balance command on several Raspberry Pis.
Fixes: 818255feece6 ("btrfs: use common helper instead of open coding a bit test") CC: stable@vger.kernel.org # 4.20+ Signed-off-by: Zygo Blaxell ce3g8jdj@umail.furryterror.org Reviewed-by: David Sterba dsterba@suse.com Signed-off-by: David Sterba dsterba@suse.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- fs/btrfs/volumes.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
--- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -3854,7 +3854,11 @@ static int alloc_profile_is_valid(u64 fl return !extended; /* "0" is valid for usual profiles */
/* true if exactly one bit set */ - return is_power_of_2(flags); + /* + * Don't use is_power_of_2(unsigned long) because it won't work + * for the single profile (1ULL << 48) on 32-bit CPUs. + */ + return flags != 0 && (flags & (flags - 1)) == 0; }
static inline int balance_need_close(struct btrfs_fs_info *fs_info)