[RFC PATCH v6 010/104] x86/virt/tdx: Add a helper function to return system wide info about TDX module

[isaku . yamahata]

From: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>

TDX KVM needs system-wide information about the TDX module, struct
tdsysinfo_struct.  Add a helper function tdx_get_sysinfo() to return it
instead of KVM getting it with various error checks.  Move out the struct
definition about it to common place tdx_host.h.

Signed-off-by: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
---
 arch/x86/include/asm/tdx.h  | 55 +++++++++++++++++++++++++++++++++++++
 arch/x86/virt/vmx/tdx/tdx.c | 16 +++++++++--
 arch/x86/virt/vmx/tdx/tdx.h | 52 -----------------------------------
 3 files changed, 69 insertions(+), 54 deletions(-)

diff --git a/arch/x86/include/asm/tdx.h b/arch/x86/include/asm/tdx.h
index f8f459e28254..0670c86de015 100644
--- a/arch/x86/include/asm/tdx.h
+++ b/arch/x86/include/asm/tdx.h
@@ -91,17 +91,72 @@ static inline long tdx_kvm_hypercall(unsigned int nr, unsigned long p1,
 #endif /* CONFIG_INTEL_TDX_GUEST && CONFIG_KVM_GUEST */
 
 #ifdef CONFIG_INTEL_TDX_HOST
+struct tdx_cpuid_config {
+	u32	leaf;
+	u32	sub_leaf;
+	u32	eax;
+	u32	ebx;
+	u32	ecx;
+	u32	edx;
+} __packed;
+
+#define TDSYSINFO_STRUCT_SIZE		1024
+#define TDSYSINFO_STRUCT_ALIGNMENT	1024
+
+struct tdsysinfo_struct {
+	/* TDX-SEAM Module Info */
+	u32	attributes;
+	u32	vendor_id;
+	u32	build_date;
+	u16	build_num;
+	u16	minor_version;
+	u16	major_version;
+	u8	reserved0[14];
+	/* Memory Info */
+	u16	max_tdmrs;
+	u16	max_reserved_per_tdmr;
+	u16	pamt_entry_size;
+	u8	reserved1[10];
+	/* Control Struct Info */
+	u16	tdcs_base_size;
+	u8	reserved2[2];
+	u16	tdvps_base_size;
+	u8	tdvps_xfam_dependent_size;
+	u8	reserved3[9];
+	/* TD Capabilities */
+	u64	attributes_fixed0;
+	u64	attributes_fixed1;
+	u64	xfam_fixed0;
+	u64	xfam_fixed1;
+	u8	reserved4[32];
+	u32	num_cpuid_config;
+	/*
+	 * The actual number of CPUID_CONFIG depends on above
+	 * 'num_cpuid_config'.  The size of 'struct tdsysinfo_struct'
+	 * is 1024B defined by TDX architecture.  Use a union with
+	 * specific padding to make 'sizeof(struct tdsysinfo_struct)'
+	 * equal to 1024.
+	 */
+	union {
+		struct tdx_cpuid_config	cpuid_configs[0];
+		u8			reserved5[892];
+	};
+} __packed __aligned(TDSYSINFO_STRUCT_ALIGNMENT);
+
 bool __seamrr_enabled(void);
 void tdx_detect_cpu(struct cpuinfo_x86 *c);
 int tdx_detect(void);
 int tdx_init(void);
 bool platform_has_tdx(void);
+const struct tdsysinfo_struct *tdx_get_sysinfo(void);
 #else
 static inline bool __seamrr_enabled(void) { return false; }
 static inline void tdx_detect_cpu(struct cpuinfo_x86 *c) { }
 static inline int tdx_detect(void) { return -ENODEV; }
 static inline int tdx_init(void) { return -ENODEV; }
 static inline bool platform_has_tdx(void) { return false; }
+struct tdsysinfo_struct;
+static inline const struct tdsysinfo_struct *tdx_get_sysinfo(void) { return NULL; }
 #endif /* CONFIG_INTEL_TDX_HOST */
 
 #endif /* !__ASSEMBLY__ */
diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c
index e8044114079d..1ef22c445126 100644
--- a/arch/x86/virt/vmx/tdx/tdx.c
+++ b/arch/x86/virt/vmx/tdx/tdx.c
@@ -645,7 +645,7 @@ static int sanitize_cmrs(struct cmr_info *cmr_array, int cmr_num)
 	return 0;
 }
 
-static int tdx_get_sysinfo(void)
+static int __tdx_get_sysinfo(void)
 {
 	struct tdx_module_output out;
 	u64 tdsysinfo_sz, cmr_num;
@@ -680,6 +680,18 @@ static int tdx_get_sysinfo(void)
 	return sanitize_cmrs(tdx_cmr_array, cmr_num);
 }
 
+const struct tdsysinfo_struct *tdx_get_sysinfo(void)
+{
+       const struct tdsysinfo_struct *r = NULL;
+
+       mutex_lock(&tdx_module_lock);
+       if (tdx_module_status == TDX_MODULE_INITIALIZED)
+	       r = &tdx_sysinfo;
+       mutex_unlock(&tdx_module_lock);
+       return r;
+}
+EXPORT_SYMBOL_GPL(tdx_get_sysinfo);
+
 /* Check whether one e820 entry is RAM and could be used as TDX memory */
 static bool e820_entry_is_ram(struct e820_entry *entry)
 {
@@ -1467,7 +1479,7 @@ static int init_tdx_module(void)
 		goto out;
 
 	/* Get TDX module information and CMRs */
-	ret = tdx_get_sysinfo();
+	ret = __tdx_get_sysinfo();
 	if (ret)
 		goto out;
 
diff --git a/arch/x86/virt/vmx/tdx/tdx.h b/arch/x86/virt/vmx/tdx/tdx.h
index 212f83374c0a..b071d299327b 100644
--- a/arch/x86/virt/vmx/tdx/tdx.h
+++ b/arch/x86/virt/vmx/tdx/tdx.h
@@ -37,58 +37,6 @@ struct cmr_info {
 #define MAX_CMRS			32
 #define CMR_INFO_ARRAY_ALIGNMENT	512
 
-struct cpuid_config {
-	u32	leaf;
-	u32	sub_leaf;
-	u32	eax;
-	u32	ebx;
-	u32	ecx;
-	u32	edx;
-} __packed;
-
-#define TDSYSINFO_STRUCT_SIZE		1024
-#define TDSYSINFO_STRUCT_ALIGNMENT	1024
-
-struct tdsysinfo_struct {
-	/* TDX-SEAM Module Info */
-	u32	attributes;
-	u32	vendor_id;
-	u32	build_date;
-	u16	build_num;
-	u16	minor_version;
-	u16	major_version;
-	u8	reserved0[14];
-	/* Memory Info */
-	u16	max_tdmrs;
-	u16	max_reserved_per_tdmr;
-	u16	pamt_entry_size;
-	u8	reserved1[10];
-	/* Control Struct Info */
-	u16	tdcs_base_size;
-	u8	reserved2[2];
-	u16	tdvps_base_size;
-	u8	tdvps_xfam_dependent_size;
-	u8	reserved3[9];
-	/* TD Capabilities */
-	u64	attributes_fixed0;
-	u64	attributes_fixed1;
-	u64	xfam_fixed0;
-	u64	xfam_fixed1;
-	u8	reserved4[32];
-	u32	num_cpuid_config;
-	/*
-	 * The actual number of CPUID_CONFIG depends on above
-	 * 'num_cpuid_config'.  The size of 'struct tdsysinfo_struct'
-	 * is 1024B defined by TDX architecture.  Use a union with
-	 * specific padding to make 'sizeof(struct tdsysinfo_struct)'
-	 * equal to 1024.
-	 */
-	union {
-		struct cpuid_config	cpuid_configs[0];
-		u8			reserved5[892];
-	};
-} __packed __aligned(TDSYSINFO_STRUCT_ALIGNMENT);
-
 struct tdmr_reserved_area {
 	u64 offset;
 	u64 size;
-- 
2.25.1