On Mon, Jun 19, 2023 at 06:32:52PM +0800, Sam Li wrote: > Stefan Hajnoczi <stefa...@redhat.com> 于2023年6月19日周一 18:10写道: > > On Mon, Jun 05, 2023 at 06:41:06PM +0800, Sam Li wrote: > > > diff --git a/block/qcow2.h b/block/qcow2.h > > > index 4f67eb912a..fe18dc4d97 100644 > > > --- a/block/qcow2.h > > > +++ b/block/qcow2.h > > > @@ -235,6 +235,20 @@ typedef struct Qcow2CryptoHeaderExtension { > > > uint64_t length; > > > } QEMU_PACKED Qcow2CryptoHeaderExtension; > > > > > > +typedef struct Qcow2ZonedHeaderExtension { > > > + /* Zoned device attributes */ > > > + BlockZonedProfile zoned_profile; > > > + BlockZoneModel zoned; > > > + uint32_t zone_size; > > > + uint32_t zone_capacity; > > > + uint32_t nr_zones; > > > + uint32_t zone_nr_conv; > > > + uint32_t max_active_zones; > > > + uint32_t max_open_zones; > > > + uint32_t max_append_sectors; > > > + uint8_t padding[3]; > > > > This looks strange. Why is there 3 bytes of padding at the end? Normally > > padding would align to an even power-of-two number of bytes like 2, 4, > > 8, etc. > > It is calculated as 3 if sizeof(zoned+zoned_profile) = 8. Else if it's > 16, the padding is 2.
I don't understand. Can you explain why there is padding at the end of this struct?
signature.asc
Description: PGP signature