• Zygo Blaxell's avatar
    btrfs: fix balance convert to single on 32-bit host CPUs · 7a547890
    Zygo Blaxell authored
    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: 818255fe ("btrfs: use common helper instead of open coding a bit test")
    CC: stable@vger.kernel.org # 4.20+
    Signed-off-by: default avatarZygo Blaxell <ce3g8jdj@umail.furryterror.org>
    Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
    Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
    7a547890
volumes.c 207 KB