[RFC PATCH v2 05/10] x86/virt/tdx: Convert the td_ctrl metadata reader

From: Chao Gao

Date: Fri Sep 18 2026 - 09:40:47 EST


Continue converting the metadata readers to the table-driven helper.

Add a table that pairs each field ID with the 'struct
tdx_sys_info_td_ctrl' member that holds its value, and read all fields by
walking that table.

Annotate the table as __initconst as it is referenced only during init.

AI was used under supervision to review code and workshop logs

Signed-off-by: Chao Gao <chao.gao@xxxxxxxxx>
---
arch/x86/virt/vmx/tdx/tdx.c | 14 ++++++++++++++
arch/x86/virt/vmx/tdx/tdx.h | 5 +++++
arch/x86/virt/vmx/tdx/tdx_global_metadata.c | 15 ---------------
3 files changed, 19 insertions(+), 15 deletions(-)

diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c
index 72aed3fc2b25..7b6b1ee075a3 100644
--- a/arch/x86/virt/vmx/tdx/tdx.c
+++ b/arch/x86/virt/vmx/tdx/tdx.c
@@ -485,6 +485,20 @@ static __init int get_tdx_sys_info_tdmr_dpamt(struct tdx_sys_info_tdmr *tdmr)
return read_sys_metadata_table(dpamt_mappings, tdmr);
}

+#define TDX_SYSINFO_MAP_TD_CTRL(_field_id, _member) \
+ TDX_SYSINFO_MAP(_field_id, struct tdx_sys_info_td_ctrl, _member)
+
+static const struct field_mapping td_ctrl_mappings[] __initconst = {
+ TDX_SYSINFO_MAP_TD_CTRL(TDR_BASE_SIZE, tdr_base_size),
+ TDX_SYSINFO_MAP_TD_CTRL(TDCS_BASE_SIZE, tdcs_base_size),
+ TDX_SYSINFO_MAP_TD_CTRL(TDVPS_BASE_SIZE, tdvps_base_size),
+};
+
+static __init int get_tdx_sys_info_td_ctrl(struct tdx_sys_info_td_ctrl *td_ctrl)
+{
+ return read_sys_metadata_table(td_ctrl_mappings, td_ctrl);
+}
+
#include "tdx_global_metadata.c"

static __init int check_features(struct tdx_sys_info *sysinfo)
diff --git a/arch/x86/virt/vmx/tdx/tdx.h b/arch/x86/virt/vmx/tdx/tdx.h
index 9a8c32b180e1..f33eb7dc7b45 100644
--- a/arch/x86/virt/vmx/tdx/tdx.h
+++ b/arch/x86/virt/vmx/tdx/tdx.h
@@ -81,6 +81,11 @@
#define TDX_MD_FIELD_ID_PAMT_1G_ENTRY_SIZE 0x9100000100000012ULL
#define TDX_MD_FIELD_ID_PAMT_PAGE_BITMAP_ENTRY_BITS 0x9100000000000013ULL

+/* Class "TD Control Structures" */
+#define TDX_MD_FIELD_ID_TDR_BASE_SIZE 0x9800000100000000ULL
+#define TDX_MD_FIELD_ID_TDCS_BASE_SIZE 0x9800000100000100ULL
+#define TDX_MD_FIELD_ID_TDVPS_BASE_SIZE 0x9800000100000200ULL
+
/* TDX page types */
#define PT_NDA 0x0
#define PT_RSVD 0x1
diff --git a/arch/x86/virt/vmx/tdx/tdx_global_metadata.c b/arch/x86/virt/vmx/tdx/tdx_global_metadata.c
index f0673dc28cb9..c6b375771265 100644
--- a/arch/x86/virt/vmx/tdx/tdx_global_metadata.c
+++ b/arch/x86/virt/vmx/tdx/tdx_global_metadata.c
@@ -7,21 +7,6 @@
* Include this file to other C file instead.
*/

-static __init int get_tdx_sys_info_td_ctrl(struct tdx_sys_info_td_ctrl *sysinfo_td_ctrl)
-{
- int ret = 0;
- u64 val;
-
- if (!ret && !(ret = read_sys_metadata_field(0x9800000100000000, &val)))
- sysinfo_td_ctrl->tdr_base_size = val;
- if (!ret && !(ret = read_sys_metadata_field(0x9800000100000100, &val)))
- sysinfo_td_ctrl->tdcs_base_size = val;
- if (!ret && !(ret = read_sys_metadata_field(0x9800000100000200, &val)))
- sysinfo_td_ctrl->tdvps_base_size = val;
-
- return ret;
-}
-
static __init int get_tdx_sys_info_td_conf(struct tdx_sys_info_td_conf *sysinfo_td_conf)
{
int ret = 0;
--
2.52.0