On Mon, Oct 12, 2020 at 02:53:12PM +0200, David Hildenbrand wrote: >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> Reviewed-by: Wei Yang <richard.weiyang@xxxxxxxxxxxxxxxxx> >--- > 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; >-- >2.26.2 -- Wei Yang Help you, Help me