[tip: x86/tdx] x86/virt/tdx: Configure TDX module with the TDMRs and global KeyID

[tip: x86/tdx] x86/virt/tdx: Configure TDX module with the TDMRs and global KeyID

[tip-bot2 for Kai Huang]

The following commit has been merged into the x86/tdx branch of tip:

Commit-ID:     554ce1c36d1bbeaec42ba870bad75e200af204be
Gitweb:        https://git.kernel.org/tip/554ce1c36d1bbeaec42ba870bad75e200af204be
Author:        Kai Huang <kai.huang@intel.com>
AuthorDate:    Fri, 08 Dec 2023 09:07:33 -08:00
Committer:     Dave Hansen <dave.hansen@linux.intel.com>
CommitterDate: Fri, 08 Dec 2023 09:12:41 -08:00

x86/virt/tdx: Configure TDX module with the TDMRs and global KeyID

The TDX module uses a private KeyID as the "global KeyID" for mapping
things like the PAMT and other TDX metadata.  This KeyID has already
been reserved when detecting TDX during the kernel early boot.

Now that the "TD Memory Regions" (TDMRs) are fully built, pass them to
the TDX module together with the global KeyID.

Signed-off-by: Kai Huang <kai.huang@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Isaku Yamahata <isaku.yamahata@intel.com>
Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Yuan Yao <yuan.yao@intel.com>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/all/20231208170740.53979-13-dave.hansen%40intel.com
---
 arch/x86/virt/vmx/tdx/tdx.c | 43 +++++++++++++++++++++++++++++++++++-
 arch/x86/virt/vmx/tdx/tdx.h |  2 ++-
 2 files changed, 44 insertions(+), 1 deletion(-)

diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c
index 98283f7..5146503 100644
--- a/arch/x86/virt/vmx/tdx/tdx.c
+++ b/arch/x86/virt/vmx/tdx/tdx.c
@@ -24,6 +24,8 @@
 #include <linux/pfn.h>
 #include <linux/align.h>
 #include <linux/sort.h>
+#include <linux/log2.h>
+#include <asm/page.h>
 #include <asm/msr-index.h>
 #include <asm/msr.h>
 #include <asm/cpufeature.h>
@@ -892,6 +894,41 @@ static int construct_tdmrs(struct list_head *tmb_list,
 	return ret;
 }
 
+static int config_tdx_module(struct tdmr_info_list *tdmr_list, u64 global_keyid)
+{
+	struct tdx_module_args args = {};
+	u64 *tdmr_pa_array;
+	size_t array_sz;
+	int i, ret;
+
+	/*
+	 * TDMRs are passed to the TDX module via an array of physical
+	 * addresses of each TDMR.  The array itself also has certain
+	 * alignment requirement.
+	 */
+	array_sz = tdmr_list->nr_consumed_tdmrs * sizeof(u64);
+	array_sz = roundup_pow_of_two(array_sz);
+	if (array_sz < TDMR_INFO_PA_ARRAY_ALIGNMENT)
+		array_sz = TDMR_INFO_PA_ARRAY_ALIGNMENT;
+
+	tdmr_pa_array = kzalloc(array_sz, GFP_KERNEL);
+	if (!tdmr_pa_array)
+		return -ENOMEM;
+
+	for (i = 0; i < tdmr_list->nr_consumed_tdmrs; i++)
+		tdmr_pa_array[i] = __pa(tdmr_entry(tdmr_list, i));
+
+	args.rcx = __pa(tdmr_pa_array);
+	args.rdx = tdmr_list->nr_consumed_tdmrs;
+	args.r8 = global_keyid;
+	ret = seamcall_prerr(TDH_SYS_CONFIG, &args);
+
+	/* Free the array as it is not required anymore. */
+	kfree(tdmr_pa_array);
+
+	return ret;
+}
+
 static int init_tdx_module(void)
 {
 	struct tdx_tdmr_sysinfo tdmr_sysinfo;
@@ -927,10 +964,14 @@ static int init_tdx_module(void)
 	if (ret)
 		goto err_free_tdmrs;
 
+	/* Pass the TDMRs and the global KeyID to the TDX module */
+	ret = config_tdx_module(&tdx_tdmr_list, tdx_global_keyid);
+	if (ret)
+		goto err_free_pamts;
+
 	/*
 	 * TODO:
 	 *
-	 *  - Configure the TDMRs and the global KeyID to the TDX module.
 	 *  - Configure the global KeyID on all packages.
 	 *  - Initialize all TDMRs.
 	 *
diff --git a/arch/x86/virt/vmx/tdx/tdx.h b/arch/x86/virt/vmx/tdx/tdx.h
index 1b04efe..fa5bcf8 100644
--- a/arch/x86/virt/vmx/tdx/tdx.h
+++ b/arch/x86/virt/vmx/tdx/tdx.h
@@ -17,6 +17,7 @@
 #define TDH_SYS_INIT		33
 #define TDH_SYS_RD		34
 #define TDH_SYS_LP_INIT		35
+#define TDH_SYS_CONFIG		45
 
 /*
  * Global scope metadata field ID.
@@ -53,6 +54,7 @@ struct tdmr_reserved_area {
 } __packed;
 
 #define TDMR_INFO_ALIGNMENT	512
+#define TDMR_INFO_PA_ARRAY_ALIGNMENT	512
 
 struct tdmr_info {
 	u64 base;