diff mbox series

[v19,005/130] x86/virt/tdx: Export global metadata read infrastructure

Message ID eec524e07ee17961a4deb1cc7a1390c91d8708ff.1708933498.git.isaku.yamahata@intel.com (mailing list archive)
State New, archived
Headers show
Series [v19,001/130] x86/virt/tdx: Rename _offset to _member for TD_SYSINFO_MAP() macro | expand

Commit Message

Isaku Yamahata Feb. 26, 2024, 8:25 a.m. UTC 
From: Kai Huang <kai.huang@intel.com>

KVM will need to read a bunch of non-TDMR related metadata to create and
run TDX guests.  Export the metadata read infrastructure for KVM to use.

Specifically, export two helpers:

1) The helper which reads multiple metadata fields to a buffer of a
   structure based on the "field ID -> structure member" mapping table.

2) The low level helper which just reads a given field ID.

The two helpers cover cases when the user wants to cache a bunch of
metadata fields to a certain structure and when the user just wants to
query a specific metadata field on demand.  They are enough for KVM to
use (and also should be enough for other potential users).

Signed-off-by: Kai Huang <kai.huang@intel.com>
Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
---
 arch/x86/include/asm/tdx.h  | 22 ++++++++++++++++++++++
 arch/x86/virt/vmx/tdx/tdx.c | 25 ++++++++-----------------
 2 files changed, 30 insertions(+), 17 deletions(-)

Comments

Yi Sun March 6, 2024, 9:05 a.m. UTC | #1 
On 26.02.2024 00:25, isaku.yamahata@intel.com wrote:
>From: Kai Huang <kai.huang@intel.com>
>
>KVM will need to read a bunch of non-TDMR related metadata to create and
>run TDX guests.  Export the metadata read infrastructure for KVM to use.
>
>Specifically, export two helpers:
>
>1) The helper which reads multiple metadata fields to a buffer of a
>   structure based on the "field ID -> structure member" mapping table.
>
>2) The low level helper which just reads a given field ID.
>
>The two helpers cover cases when the user wants to cache a bunch of
>metadata fields to a certain structure and when the user just wants to
>query a specific metadata field on demand.  They are enough for KVM to
>use (and also should be enough for other potential users).
>
>Signed-off-by: Kai Huang <kai.huang@intel.com>
>Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
>Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
>---
> arch/x86/include/asm/tdx.h  | 22 ++++++++++++++++++++++
> arch/x86/virt/vmx/tdx/tdx.c | 25 ++++++++-----------------
> 2 files changed, 30 insertions(+), 17 deletions(-)
>
>diff --git a/arch/x86/include/asm/tdx.h b/arch/x86/include/asm/tdx.h
>index eba178996d84..709b9483f9e4 100644
>--- a/arch/x86/include/asm/tdx.h
>+++ b/arch/x86/include/asm/tdx.h
>@@ -116,6 +116,28 @@ static inline u64 sc_retry(sc_func_t func, u64 fn,
> int tdx_cpu_enable(void);
> int tdx_enable(void);
> const char *tdx_dump_mce_info(struct mce *m);
>+
>+struct tdx_metadata_field_mapping {
>+	u64 field_id;
>+	int offset;
>+	int size;
>+};
>+
>+#define TD_SYSINFO_MAP(_field_id, _struct, _member)	\
>+	{ .field_id = MD_FIELD_ID_##_field_id,		\
>+	  .offset   = offsetof(_struct, _member),	\
>+	  .size     = sizeof(typeof(((_struct *)0)->_member)) }
>+
>+/*
>+ * Read multiple global metadata fields to a buffer of a structure
>+ * based on the "field ID -> structure member" mapping table.
>+ */
>+int tdx_sys_metadata_read(const struct tdx_metadata_field_mapping *fields,
>+			  int nr_fields, void *stbuf);
>+
>+/* Read a single global metadata field */
>+int tdx_sys_metadata_field_read(u64 field_id, u64 *data);
>+
> #else
> static inline void tdx_init(void) { }
> static inline int tdx_cpu_enable(void) { return -ENODEV; }
>diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c
>index a19adc898df6..dc21310776ab 100644
>--- a/arch/x86/virt/vmx/tdx/tdx.c
>+++ b/arch/x86/virt/vmx/tdx/tdx.c
>@@ -251,7 +251,7 @@ static int build_tdx_memlist(struct list_head *tmb_list)
> 	return ret;
> }
>
>-static int read_sys_metadata_field(u64 field_id, u64 *data)
>+int tdx_sys_metadata_field_read(u64 field_id, u64 *data)
> {
> 	struct tdx_module_args args = {};
> 	int ret;
>@@ -270,6 +270,7 @@ static int read_sys_metadata_field(u64 field_id, u64 *data)
>
> 	return 0;
> }
>+EXPORT_SYMBOL_GPL(tdx_sys_metadata_field_read);
>
> /* Return the metadata field element size in bytes */
> static int get_metadata_field_bytes(u64 field_id)
>@@ -295,7 +296,7 @@ static int stbuf_read_sys_metadata_field(u64 field_id,
> 	if (WARN_ON_ONCE(get_metadata_field_bytes(field_id) != bytes))
> 		return -EINVAL;
>
>-	ret = read_sys_metadata_field(field_id, &tmp);
>+	ret = tdx_sys_metadata_field_read(field_id, &tmp);
> 	if (ret)
> 		return ret;
>
>@@ -304,19 +305,8 @@ static int stbuf_read_sys_metadata_field(u64 field_id,
> 	return 0;
> }
>
>-struct field_mapping {
>-	u64 field_id;
>-	int offset;
>-	int size;
>-};
>-
>-#define TD_SYSINFO_MAP(_field_id, _struct, _member)	\
>-	{ .field_id = MD_FIELD_ID_##_field_id,		\
>-	  .offset   = offsetof(_struct, _member),	\
>-	  .size     = sizeof(typeof(((_struct *)0)->_member)) }
>-
>-static int read_sys_metadata(struct field_mapping *fields, int nr_fields,
>-			     void *stbuf)
>+int tdx_sys_metadata_read(const struct tdx_metadata_field_mapping *fields,
>+			  int nr_fields, void *stbuf)
> {
> 	int i, ret;
>
>@@ -331,6 +321,7 @@ static int read_sys_metadata(struct field_mapping *fields, int nr_fields,
>
> 	return 0;
> }
>+EXPORT_SYMBOL_GPL(tdx_sys_metadata_read);
Hi Kai,

The two helpers can potentially be used by TD guests, as you mentioned.
It's a good idea to declare it in the header asm/tdx.h.

However, the function cannot be compiled if its definition remains in the
vmx/tdx/tdx.c file while disabling the CONFIG_TDX_HOST.

It would be better to move the definition to a shared location,
allowing the host and guest to share the same code.

Thanks
   --Sun, Yi
Huang, Kai March 6, 2024, 9:23 p.m. UTC | #2 
> 
> However, the function cannot be compiled if its definition remains in the
> vmx/tdx/tdx.c file while disabling the CONFIG_TDX_HOST.
> 
> It would be better to move the definition to a shared location,
> allowing the host and guest to share the same code.
> 

No not in this series.  Such change needs to be in your series.

Thanks,
-Kai
Binbin Wu March 8, 2024, 8:31 a.m. UTC | #3 
On 2/26/2024 4:25 PM, isaku.yamahata@intel.com wrote:
> From: Kai Huang <kai.huang@intel.com>
>
> KVM will need to read a bunch of non-TDMR related metadata to create and
> run TDX guests.  Export the metadata read infrastructure for KVM to use.
>
> Specifically, export two helpers:
>
> 1) The helper which reads multiple metadata fields to a buffer of a
>     structure based on the "field ID -> structure member" mapping table.
>
> 2) The low level helper which just reads a given field ID.
>
> The two helpers cover cases when the user wants to cache a bunch of
> metadata fields to a certain structure and when the user just wants to
> query a specific metadata field on demand.  They are enough for KVM to
> use (and also should be enough for other potential users).
>
> Signed-off-by: Kai Huang <kai.huang@intel.com>
> Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>

Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com>

> ---
>   arch/x86/include/asm/tdx.h  | 22 ++++++++++++++++++++++
>   arch/x86/virt/vmx/tdx/tdx.c | 25 ++++++++-----------------
>   2 files changed, 30 insertions(+), 17 deletions(-)
>
> diff --git a/arch/x86/include/asm/tdx.h b/arch/x86/include/asm/tdx.h
> index eba178996d84..709b9483f9e4 100644
> --- a/arch/x86/include/asm/tdx.h
> +++ b/arch/x86/include/asm/tdx.h
> @@ -116,6 +116,28 @@ static inline u64 sc_retry(sc_func_t func, u64 fn,
>   int tdx_cpu_enable(void);
>   int tdx_enable(void);
>   const char *tdx_dump_mce_info(struct mce *m);
> +
> +struct tdx_metadata_field_mapping {
> +	u64 field_id;
> +	int offset;
> +	int size;
> +};
> +
> +#define TD_SYSINFO_MAP(_field_id, _struct, _member)	\
> +	{ .field_id = MD_FIELD_ID_##_field_id,		\
> +	  .offset   = offsetof(_struct, _member),	\
> +	  .size     = sizeof(typeof(((_struct *)0)->_member)) }
> +
> +/*
> + * Read multiple global metadata fields to a buffer of a structure
> + * based on the "field ID -> structure member" mapping table.
> + */
> +int tdx_sys_metadata_read(const struct tdx_metadata_field_mapping *fields,
> +			  int nr_fields, void *stbuf);
> +
> +/* Read a single global metadata field */
> +int tdx_sys_metadata_field_read(u64 field_id, u64 *data);
> +
>   #else
>   static inline void tdx_init(void) { }
>   static inline int tdx_cpu_enable(void) { return -ENODEV; }
> diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c
> index a19adc898df6..dc21310776ab 100644
> --- a/arch/x86/virt/vmx/tdx/tdx.c
> +++ b/arch/x86/virt/vmx/tdx/tdx.c
> @@ -251,7 +251,7 @@ static int build_tdx_memlist(struct list_head *tmb_list)
>   	return ret;
>   }
>   
> -static int read_sys_metadata_field(u64 field_id, u64 *data)
> +int tdx_sys_metadata_field_read(u64 field_id, u64 *data)
>   {
>   	struct tdx_module_args args = {};
>   	int ret;
> @@ -270,6 +270,7 @@ static int read_sys_metadata_field(u64 field_id, u64 *data)
>   
>   	return 0;
>   }
> +EXPORT_SYMBOL_GPL(tdx_sys_metadata_field_read);
>   
>   /* Return the metadata field element size in bytes */
>   static int get_metadata_field_bytes(u64 field_id)
> @@ -295,7 +296,7 @@ static int stbuf_read_sys_metadata_field(u64 field_id,
>   	if (WARN_ON_ONCE(get_metadata_field_bytes(field_id) != bytes))
>   		return -EINVAL;
>   
> -	ret = read_sys_metadata_field(field_id, &tmp);
> +	ret = tdx_sys_metadata_field_read(field_id, &tmp);
>   	if (ret)
>   		return ret;
>   
> @@ -304,19 +305,8 @@ static int stbuf_read_sys_metadata_field(u64 field_id,
>   	return 0;
>   }
>   
> -struct field_mapping {
> -	u64 field_id;
> -	int offset;
> -	int size;
> -};
> -
> -#define TD_SYSINFO_MAP(_field_id, _struct, _member)	\
> -	{ .field_id = MD_FIELD_ID_##_field_id,		\
> -	  .offset   = offsetof(_struct, _member),	\
> -	  .size     = sizeof(typeof(((_struct *)0)->_member)) }
> -
> -static int read_sys_metadata(struct field_mapping *fields, int nr_fields,
> -			     void *stbuf)
> +int tdx_sys_metadata_read(const struct tdx_metadata_field_mapping *fields,
> +			  int nr_fields, void *stbuf)
>   {
>   	int i, ret;
>   
> @@ -331,6 +321,7 @@ static int read_sys_metadata(struct field_mapping *fields, int nr_fields,
>   
>   	return 0;
>   }
> +EXPORT_SYMBOL_GPL(tdx_sys_metadata_read);
>   
>   #define TD_SYSINFO_MAP_TDMR_INFO(_field_id, _member)	\
>   	TD_SYSINFO_MAP(_field_id, struct tdx_tdmr_sysinfo, _member)
> @@ -338,7 +329,7 @@ static int read_sys_metadata(struct field_mapping *fields, int nr_fields,
>   static int get_tdx_tdmr_sysinfo(struct tdx_tdmr_sysinfo *tdmr_sysinfo)
>   {
>   	/* Map TD_SYSINFO fields into 'struct tdx_tdmr_sysinfo': */
> -	const struct field_mapping fields[] = {
> +	const struct tdx_metadata_field_mapping fields[] = {
>   		TD_SYSINFO_MAP_TDMR_INFO(MAX_TDMRS,		max_tdmrs),
>   		TD_SYSINFO_MAP_TDMR_INFO(MAX_RESERVED_PER_TDMR, max_reserved_per_tdmr),
>   		TD_SYSINFO_MAP_TDMR_INFO(PAMT_4K_ENTRY_SIZE,    pamt_entry_size[TDX_PS_4K]),
> @@ -347,7 +338,7 @@ static int get_tdx_tdmr_sysinfo(struct tdx_tdmr_sysinfo *tdmr_sysinfo)
>   	};
>   
>   	/* Populate 'tdmr_sysinfo' fields using the mapping structure above: */
> -	return read_sys_metadata(fields, ARRAY_SIZE(fields), tdmr_sysinfo);
> +	return tdx_sys_metadata_read(fields, ARRAY_SIZE(fields), tdmr_sysinfo);
>   }
>   
>   /* Calculate the actual TDMR size */
diff mbox series

Patch

diff --git a/arch/x86/include/asm/tdx.h b/arch/x86/include/asm/tdx.h
index eba178996d84..709b9483f9e4 100644
--- a/arch/x86/include/asm/tdx.h
+++ b/arch/x86/include/asm/tdx.h
@@ -116,6 +116,28 @@  static inline u64 sc_retry(sc_func_t func, u64 fn,
 int tdx_cpu_enable(void);
 int tdx_enable(void);
 const char *tdx_dump_mce_info(struct mce *m);
+
+struct tdx_metadata_field_mapping {
+	u64 field_id;
+	int offset;
+	int size;
+};
+
+#define TD_SYSINFO_MAP(_field_id, _struct, _member)	\
+	{ .field_id = MD_FIELD_ID_##_field_id,		\
+	  .offset   = offsetof(_struct, _member),	\
+	  .size     = sizeof(typeof(((_struct *)0)->_member)) }
+
+/*
+ * Read multiple global metadata fields to a buffer of a structure
+ * based on the "field ID -> structure member" mapping table.
+ */
+int tdx_sys_metadata_read(const struct tdx_metadata_field_mapping *fields,
+			  int nr_fields, void *stbuf);
+
+/* Read a single global metadata field */
+int tdx_sys_metadata_field_read(u64 field_id, u64 *data);
+
 #else
 static inline void tdx_init(void) { }
 static inline int tdx_cpu_enable(void) { return -ENODEV; }
diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c
index a19adc898df6..dc21310776ab 100644
--- a/arch/x86/virt/vmx/tdx/tdx.c
+++ b/arch/x86/virt/vmx/tdx/tdx.c
@@ -251,7 +251,7 @@  static int build_tdx_memlist(struct list_head *tmb_list)
 	return ret;
 }
 
-static int read_sys_metadata_field(u64 field_id, u64 *data)
+int tdx_sys_metadata_field_read(u64 field_id, u64 *data)
 {
 	struct tdx_module_args args = {};
 	int ret;
@@ -270,6 +270,7 @@  static int read_sys_metadata_field(u64 field_id, u64 *data)
 
 	return 0;
 }
+EXPORT_SYMBOL_GPL(tdx_sys_metadata_field_read);
 
 /* Return the metadata field element size in bytes */
 static int get_metadata_field_bytes(u64 field_id)
@@ -295,7 +296,7 @@  static int stbuf_read_sys_metadata_field(u64 field_id,
 	if (WARN_ON_ONCE(get_metadata_field_bytes(field_id) != bytes))
 		return -EINVAL;
 
-	ret = read_sys_metadata_field(field_id, &tmp);
+	ret = tdx_sys_metadata_field_read(field_id, &tmp);
 	if (ret)
 		return ret;
 
@@ -304,19 +305,8 @@  static int stbuf_read_sys_metadata_field(u64 field_id,
 	return 0;
 }
 
-struct field_mapping {
-	u64 field_id;
-	int offset;
-	int size;
-};
-
-#define TD_SYSINFO_MAP(_field_id, _struct, _member)	\
-	{ .field_id = MD_FIELD_ID_##_field_id,		\
-	  .offset   = offsetof(_struct, _member),	\
-	  .size     = sizeof(typeof(((_struct *)0)->_member)) }
-
-static int read_sys_metadata(struct field_mapping *fields, int nr_fields,
-			     void *stbuf)
+int tdx_sys_metadata_read(const struct tdx_metadata_field_mapping *fields,
+			  int nr_fields, void *stbuf)
 {
 	int i, ret;
 
@@ -331,6 +321,7 @@  static int read_sys_metadata(struct field_mapping *fields, int nr_fields,
 
 	return 0;
 }
+EXPORT_SYMBOL_GPL(tdx_sys_metadata_read);
 
 #define TD_SYSINFO_MAP_TDMR_INFO(_field_id, _member)	\
 	TD_SYSINFO_MAP(_field_id, struct tdx_tdmr_sysinfo, _member)
@@ -338,7 +329,7 @@  static int read_sys_metadata(struct field_mapping *fields, int nr_fields,
 static int get_tdx_tdmr_sysinfo(struct tdx_tdmr_sysinfo *tdmr_sysinfo)
 {
 	/* Map TD_SYSINFO fields into 'struct tdx_tdmr_sysinfo': */
-	const struct field_mapping fields[] = {
+	const struct tdx_metadata_field_mapping fields[] = {
 		TD_SYSINFO_MAP_TDMR_INFO(MAX_TDMRS,		max_tdmrs),
 		TD_SYSINFO_MAP_TDMR_INFO(MAX_RESERVED_PER_TDMR, max_reserved_per_tdmr),
 		TD_SYSINFO_MAP_TDMR_INFO(PAMT_4K_ENTRY_SIZE,    pamt_entry_size[TDX_PS_4K]),
@@ -347,7 +338,7 @@  static int get_tdx_tdmr_sysinfo(struct tdx_tdmr_sysinfo *tdmr_sysinfo)
 	};
 
 	/* Populate 'tdmr_sysinfo' fields using the mapping structure above: */
-	return read_sys_metadata(fields, ARRAY_SIZE(fields), tdmr_sysinfo);
+	return tdx_sys_metadata_read(fields, ARRAY_SIZE(fields), tdmr_sysinfo);
 }
 
 /* Calculate the actual TDMR size */