> The calculation is already complicated enough, let's limit it to one
> location.
>
> Cc: "Michael S. Tsirkin" <mst@xxxxxxxxxx>
> Cc: Jason Wang <jasowang@xxxxxxxxxx>
> Cc: Pankaj Gupta <pankaj.gupta.linux@xxxxxxxxx>
> Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
> ---
> drivers/virtio/virtio_mem.c | 20 +++++++++++++++-----
> 1 file changed, 15 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/virtio/virtio_mem.c b/drivers/virtio/virtio_mem.c
> index 2cc497ad8298..73ff6e9ba839 100644
> --- a/drivers/virtio/virtio_mem.c
> +++ b/drivers/virtio/virtio_mem.c
> @@ -327,6 +327,16 @@ static int virtio_mem_sbm_mb_states_prepare_next_mb(struct virtio_mem *vm)
> _mb_id--) \
> if (virtio_mem_sbm_get_mb_state(_vm, _mb_id) == _state)
>
> +/*
> + * Calculate the bit number in the sb_states bitmap for the given subblock
> + * inside the given memory block.
> + */
> +static int virtio_mem_sbm_sb_state_bit_nr(struct virtio_mem *vm,
> + unsigned long mb_id, int sb_id)
> +{
> + return (mb_id - vm->first_mb_id) * vm->nb_sb_per_mb + sb_id;
> +}
> +
> /*
> * Mark all selected subblocks plugged.
> *
> @@ -336,7 +346,7 @@ static void virtio_mem_sbm_set_sb_plugged(struct virtio_mem *vm,
> unsigned long mb_id, int sb_id,
> int count)
> {
> - const int bit = (mb_id - vm->first_mb_id) * vm->nb_sb_per_mb + sb_id;
> + const int bit = virtio_mem_sbm_sb_state_bit_nr(vm, mb_id, sb_id);
>
> __bitmap_set(vm->sbm.sb_states, bit, count);
> }
> @@ -350,7 +360,7 @@ static void virtio_mem_sbm_set_sb_unplugged(struct virtio_mem *vm,
> unsigned long mb_id, int sb_id,
> int count)
> {
> - const int bit = (mb_id - vm->first_mb_id) * vm->nb_sb_per_mb + sb_id;
> + const int bit = virtio_mem_sbm_sb_state_bit_nr(vm, mb_id, sb_id);
>
> __bitmap_clear(vm->sbm.sb_states, bit, count);
> }
> @@ -362,7 +372,7 @@ static bool virtio_mem_sbm_test_sb_plugged(struct virtio_mem *vm,
> unsigned long mb_id, int sb_id,
> int count)
> {
> - const int bit = (mb_id - vm->first_mb_id) * vm->nb_sb_per_mb + sb_id;
> + const int bit = virtio_mem_sbm_sb_state_bit_nr(vm, mb_id, sb_id);
>
> if (count == 1)
> return test_bit(bit, vm->sbm.sb_states);
> @@ -379,7 +389,7 @@ static bool virtio_mem_sbm_test_sb_unplugged(struct virtio_mem *vm,
> unsigned long mb_id, int sb_id,
> int count)
> {
> - const int bit = (mb_id - vm->first_mb_id) * vm->nb_sb_per_mb + sb_id;
> + const int bit = virtio_mem_sbm_sb_state_bit_nr(vm, mb_id, sb_id);
>
> /* TODO: Helper similar to bitmap_set() */
> return find_next_bit(vm->sbm.sb_states, bit + count, bit) >=
> @@ -393,7 +403,7 @@ static bool virtio_mem_sbm_test_sb_unplugged(struct virtio_mem *vm,
> static int virtio_mem_sbm_first_unplugged_sb(struct virtio_mem *vm,
> unsigned long mb_id)
> {
> - const int bit = (mb_id - vm->first_mb_id) * vm->nb_sb_per_mb;
> + const int bit = virtio_mem_sbm_sb_state_bit_nr(vm, mb_id, 0);
>
> return find_next_zero_bit(vm->sbm.sb_states,
> bit + vm->nb_sb_per_mb, bit) - bit;
Agree, there are alot of *b things, good to clean as much.
Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@xxxxxxxxx>
