Hi Dave,
On 11/14/22 4:54 PM, Dave Hansen wrote:
In both the commit log and the comments, I can highlight the "subtype 0" information. Will that work for you, or do you prefer that this wrapper take the "subtype" option as argument and we pass 0 for the subtype value from the TDX guest driver?
I actually think it's a *lot* more clear if the User<->Kernel ABI just takes the subtype. But, I also heard Greg's concerns about making the ABI _too_ open-ended.
So, I really don't care. Just make it clear that, as is, this ABI is not the "TDREPORT ABI".
Are you fine with the following version?
+/* TDX Module call error codes */ +#define TDCALL_RETURN_CODE(a) ((a) >> 32) +#define TDCALL_INVALID_OPERAND 0xc0000100 + +#define TDREPORT_SUBTYPE_0 0 + +/** + * tdx_mcall_get_report0() - Wrapper to get TDREPORT0 (a.k.a. TDREPORT + * subtype 0) using TDG.MR.REPORT TDCALL. + * @reportdata: Address of the input buffer which contains user-defined + * REPORTDATA to be included into TDREPORT. + * @tdreport: Address of the output buffer to store TDREPORT. + * + * Refer to section titled "TDG.MR.REPORT leaf" in the TDX Module + * v1.0 specification for more information on TDG.MR.REPORT TDCALL. + * It is used in the TDX guest driver module to get the TDREPORT0. + * + * Return 0 on success, -EINVAL for invalid operands, or -EIO on + * other TDCALL failures. + */ +int tdx_mcall_get_report0(u8 *reportdata, u8 *tdreport) +{ + u64 ret; + + ret = __tdx_module_call(TDX_GET_REPORT, virt_to_phys(tdreport), + virt_to_phys(reportdata), TDREPORT_SUBTYPE_0, + 0, NULL); + if (ret) { + if (TDCALL_RETURN_CODE(ret) == TDCALL_INVALID_OPERAND) + return -EINVAL; + return -EIO; + } + + return 0; +} +EXPORT_SYMBOL_GPL(tdx_mcall_get_report0);