[RFC PATCH v2 06/10] x86/virt/tdx: Convert the handoff metadata reader

[Chao Gao <chao.gao@intel.com>]

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

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

AI was used under supervision to review code and workshop logs

Signed-off-by: Chao Gao <chao.gao@intel.com>
---
 arch/x86/virt/vmx/tdx/tdx.c                 | 12 ++++++++++++
 arch/x86/virt/vmx/tdx/tdx.h                 |  3 +++
 arch/x86/virt/vmx/tdx/tdx_global_metadata.c | 13 -------------
 3 files changed, 15 insertions(+), 13 deletions(-)

diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c
index 7b6b1ee075a3..2bd7a2c9432b 100644
--- a/arch/x86/virt/vmx/tdx/tdx.c
+++ b/arch/x86/virt/vmx/tdx/tdx.c
@@ -499,6 +499,18 @@ 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);
 }
 
+#define TDX_SYSINFO_MAP_HANDOFF(_field_id, _member) \
+	TDX_SYSINFO_MAP(_field_id, struct tdx_sys_info_handoff, _member)
+
+static const struct field_mapping handoff_mappings[] = {
+	TDX_SYSINFO_MAP_HANDOFF(MODULE_HV, module_hv),
+};
+
+static int get_tdx_sys_info_handoff(struct tdx_sys_info_handoff *handoff)
+{
+	return read_sys_metadata_table(handoff_mappings, handoff);
+}
+
 #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 f33eb7dc7b45..6f99e4cdcc19 100644
--- a/arch/x86/virt/vmx/tdx/tdx.h
+++ b/arch/x86/virt/vmx/tdx/tdx.h
@@ -86,6 +86,9 @@
 #define TDX_MD_FIELD_ID_TDCS_BASE_SIZE			0x9800000100000100ULL
 #define TDX_MD_FIELD_ID_TDVPS_BASE_SIZE			0x9800000100000200ULL
 
+/* Class "TDX Module Handoff" */
+#define TDX_MD_FIELD_ID_MODULE_HV			0x8900000100000000ULL
+
 /* 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 c6b375771265..36bbf42dead9 100644
--- a/arch/x86/virt/vmx/tdx/tdx_global_metadata.c
+++ b/arch/x86/virt/vmx/tdx/tdx_global_metadata.c
@@ -40,19 +40,6 @@ static __init int get_tdx_sys_info_td_conf(struct tdx_sys_info_td_conf *sysinfo_
 	return ret;
 }
 
-static int get_tdx_sys_info_handoff(struct tdx_sys_info_handoff *sysinfo_handoff)
-{
-	int ret;
-	u64 val;
-
-	ret = read_sys_metadata_field(0x8900000100000000, &val);
-	if (ret)
-		return ret;
-
-	sysinfo_handoff->module_hv = val;
-	return 0;
-}
-
 static __init int get_tdx_sys_info(struct tdx_sys_info *sysinfo)
 {
 	int ret = 0;
-- 
2.52.0