[PATCH v4 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>
Reviewed-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
---
v4:
 - Collect tags [Rick]
 - Drop per-class macros [Nikolay, Dave]
---
 arch/x86/virt/vmx/tdx/tdx.c                 |  6 +++++-
 arch/x86/virt/vmx/tdx/tdx.h                 |  3 +++
 arch/x86/virt/vmx/tdx/tdx_global_metadata.c | 13 -------------
 3 files changed, 8 insertions(+), 14 deletions(-)

diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c
index bd0c8359eb55..ebf9d4d721e1 100644
--- a/arch/x86/virt/vmx/tdx/tdx.c
+++ b/arch/x86/virt/vmx/tdx/tdx.c
@@ -467,6 +467,10 @@ static const struct field_mapping td_ctrl_mappings[] __initconst = {
 	FIELD_MAP(TDX_FIELD_TDVPS_BASE_SIZE,	td_ctrl, tdvps_base_size),
 };
 
+static const struct field_mapping handoff_mappings[] = {
+	FIELD_MAP(TDX_FIELD_MODULE_HV, handoff, module_hv),
+};
+
 #include "tdx_global_metadata.c"
 
 static __init int check_features(struct tdx_sys_info *sysinfo)
@@ -1394,7 +1398,7 @@ int tdx_module_shutdown(void)
 	int ret;
 	int cpu;
 
-	ret = get_tdx_sys_info_handoff(&handoff);
+	ret = read_sys_metadata_table(handoff_mappings, &handoff);
 	/*
 	 * Handoff information is required for proper
 	 * shutdown. Refuse to shut down without it.
diff --git a/arch/x86/virt/vmx/tdx/tdx.h b/arch/x86/virt/vmx/tdx/tdx.h
index 8bd8928c1802..720e301f599e 100644
--- a/arch/x86/virt/vmx/tdx/tdx.h
+++ b/arch/x86/virt/vmx/tdx/tdx.h
@@ -78,6 +78,9 @@
 #define TDX_FIELD_TDCS_BASE_SIZE		0x9800000100000100ULL
 #define TDX_FIELD_TDVPS_BASE_SIZE		0x9800000100000200ULL
 
+/* Class "TDX Module Handoff" */
+#define TDX_FIELD_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 6025421874cd..f1aeccd08027 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