On Tue, Jun 27, 2023 at 02:12:44AM +1200, Kai Huang wrote:
> The TDX module uses a private KeyID as the "global KeyID" for mapping
> things like the PAMT and other TDX metadata. This KeyID has already
> been reserved when detecting TDX during the kernel early boot.
>
> After the list of "TD Memory Regions" (TDMRs) has been constructed to
> cover all TDX-usable memory regions, the next step is to pass them to
> the TDX module together with the global KeyID.
Reviewed-by: Yuan Yao <yuan.yao@xxxxxxxxx>
>
> Signed-off-by: Kai Huang <kai.huang@xxxxxxxxx>
> Reviewed-by: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
> Reviewed-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
> ---
>
> v11 -> v12:
> - Added Kirill's tag
>
> v10 -> v11:
> - No update
>
> v9 -> v10:
> - Code change due to change static 'tdx_tdmr_list' to local 'tdmr_list'.
>
> v8 -> v9:
> - Improved changlog to explain why initializing TDMRs can take long
> time (Dave).
> - Improved comments around 'next-to-initialize' address (Dave).
>
> v7 -> v8: (Dave)
> - Changelog:
> - explicitly call out this is the last step of TDX module initialization.
> - Trimed down changelog by removing SEAMCALL name and details.
> - Removed/trimmed down unnecessary comments.
> - Other changes due to 'struct tdmr_info_list'.
>
> v6 -> v7:
> - Removed need_resched() check. -- Andi.
>
>
> ---
> arch/x86/virt/vmx/tdx/tdx.c | 41 ++++++++++++++++++++++++++++++++++++-
> arch/x86/virt/vmx/tdx/tdx.h | 2 ++
> 2 files changed, 42 insertions(+), 1 deletion(-)
>
> diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c
> index 2bcace5cb25c..1992245290de 100644
> --- a/arch/x86/virt/vmx/tdx/tdx.c
> +++ b/arch/x86/virt/vmx/tdx/tdx.c
> @@ -26,6 +26,7 @@
> #include <linux/pfn.h>
> #include <linux/align.h>
> #include <linux/sort.h>
> +#include <linux/log2.h>
> #include <asm/msr-index.h>
> #include <asm/msr.h>
> #include <asm/archrandom.h>
> @@ -864,6 +865,39 @@ static int construct_tdmrs(struct list_head *tmb_list,
> return ret;
> }
>
> +static int config_tdx_module(struct tdmr_info_list *tdmr_list, u64 global_keyid)
> +{
> + u64 *tdmr_pa_array;
> + size_t array_sz;
> + int i, ret;
> +
> + /*
> + * TDMRs are passed to the TDX module via an array of physical
> + * addresses of each TDMR. The array itself also has certain
> + * alignment requirement.
> + */
> + array_sz = tdmr_list->nr_consumed_tdmrs * sizeof(u64);
> + array_sz = roundup_pow_of_two(array_sz);
> + if (array_sz < TDMR_INFO_PA_ARRAY_ALIGNMENT)
> + array_sz = TDMR_INFO_PA_ARRAY_ALIGNMENT;
> +
> + tdmr_pa_array = kzalloc(array_sz, GFP_KERNEL);
> + if (!tdmr_pa_array)
> + return -ENOMEM;
> +
> + for (i = 0; i < tdmr_list->nr_consumed_tdmrs; i++)
> + tdmr_pa_array[i] = __pa(tdmr_entry(tdmr_list, i));
> +
> + ret = seamcall(TDH_SYS_CONFIG, __pa(tdmr_pa_array),
> + tdmr_list->nr_consumed_tdmrs,
> + global_keyid, 0, NULL, NULL);
> +
> + /* Free the array as it is not required anymore. */
> + kfree(tdmr_pa_array);
> +
> + return ret;
> +}
> +
> static int init_tdx_module(void)
> {
> struct tdsysinfo_struct *sysinfo;
> @@ -917,16 +951,21 @@ static int init_tdx_module(void)
> if (ret)
> goto out_free_tdmrs;
>
> + /* Pass the TDMRs and the global KeyID to the TDX module */
> + ret = config_tdx_module(&tdmr_list, tdx_global_keyid);
> + if (ret)
> + goto out_free_pamts;
> +
> /*
> * TODO:
> *
> - * - Configure the TDMRs and the global KeyID to the TDX module.
> * - Configure the global KeyID on all packages.
> * - Initialize all TDMRs.
> *
> * Return error before all steps are done.
> */
> ret = -EINVAL;
> +out_free_pamts:
> if (ret)
> tdmrs_free_pamt_all(&tdmr_list);
> else
> diff --git a/arch/x86/virt/vmx/tdx/tdx.h b/arch/x86/virt/vmx/tdx/tdx.h
> index 9b5a65f37e8b..c386aa3afe2a 100644
> --- a/arch/x86/virt/vmx/tdx/tdx.h
> +++ b/arch/x86/virt/vmx/tdx/tdx.h
> @@ -24,6 +24,7 @@
> #define TDH_SYS_INFO 32
> #define TDH_SYS_INIT 33
> #define TDH_SYS_LP_INIT 35
> +#define TDH_SYS_CONFIG 45
>
> struct cmr_info {
> u64 base;
> @@ -88,6 +89,7 @@ struct tdmr_reserved_area {
> } __packed;
>
> #define TDMR_INFO_ALIGNMENT 512
> +#define TDMR_INFO_PA_ARRAY_ALIGNMENT 512
>
> struct tdmr_info {
> u64 base;
> --
> 2.40.1
>
