On Fri, 2024-05-03 at 00:07 +0000, Edgecombe, Rick P wrote:
> On Sat, 2024-03-02 at 00:20 +1300, Kai Huang wrote:
> > TD_SYSINFO_MAP() macro actually takes the member of the 'struct
> > tdx_tdmr_sysinfo' as the second argument and uses the offsetof() to
> > calculate the offset for that member.
> >
> > Rename the macro argument _offset to _member to reflect this.
>
> The KVM patches will want to use this macro. The fact that it is misnamed will
> percolate into the KVM code if it is not updated before it gets wider callers.
> (This is a reason why this is good change from KVM's perspective).
>
> See the KVM code below:
>
> #define TDX_INFO_MAP(_field_id, _member) \
> TD_SYSINFO_MAP(_field_id, struct st, _member)
>
> struct tdx_metadata_field_mapping st_fields[] = {
> TDX_INFO_MAP(NUM_CPUID_CONFIG, num_cpuid_config),
> TDX_INFO_MAP(TDCS_BASE_SIZE, tdcs_base_size),
> TDX_INFO_MAP(TDVPS_BASE_SIZE, tdvps_base_size),
> };
> #undef TDX_INFO_MAP
>
> #define TDX_INFO_MAP(_field_id, _member) \
> TD_SYSINFO_MAP(_field_id, struct tdx_info, _member)
>
> struct tdx_metadata_field_mapping fields[] = {
> TDX_INFO_MAP(FEATURES0, features0),
> TDX_INFO_MAP(ATTRS_FIXED0, attributes_fixed0),
> TDX_INFO_MAP(ATTRS_FIXED1, attributes_fixed1),
> TDX_INFO_MAP(XFAM_FIXED0, xfam_fixed0),
> TDX_INFO_MAP(XFAM_FIXED1, xfam_fixed1),
> };
> #undef TDX_INFO_MAP
I was thinking how to respond. I guess your point is we can also mention
KVM will need to use this too so it's better to change it before it gets
wider callers. But I don't think it is needed because if it is misnamed
now then we already have a justification to do it.
And technically, I don't think the argument name used in KVM actually has
anything to do with the argument name used in the TD_SYSINFO_MAP() macro
definition here. What really matters is when they get used, we need to
pass the "real struct member":
struct whatever {
u64 a;
u16 b;
};
#define TDX_INFO_MAP_WHATEVER(_field_id, _xyz) \
TD_SYSINFO_MAP(_field_id, struct whatever, _xyz)
const struct tdx_metadata_field_mapping fields[] = {
TDX_INFO_MAP_WHATEVER(_FIELD_A, a),
TDX_INFO_MAP_WHATEVER(_FIELD_B, b),
};
No?
