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

diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c
index 98283f728a816907e2de1fdb41de07aeb28b40e7..5146503233c07b9331d5931ef9b776b6ede80102 100644 (file)
--- 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 1b04efece9dbddc01fd1a22b714557db4c8e4b68..fa5bcf8b5a9ca70434d15ee3380834ea265ed4c0 100644 (file)
--- 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;