[RFC,v3,20/36] i386/tdx: Get and store the mem_ptr of TDVF firmware

Commit Message

Xiaoyao Li March 17, 2022, 1:58 p.m. UTC

QEMU needs to later copy the context of TDVF firmware to guest private
memory. So get the mem_ptr of CODE.fd and VARS.fd and store them in
tdx_guest object.

Signed-off-by: Xiaoyao Li <[e-mail]>
---
 hw/i386/pc_sysfw.c         | 20 ++++++++++++--------
 include/hw/i386/tdvf.h     |  4 ++++
 target/i386/kvm/tdx-stub.c |  5 +++++
 target/i386/kvm/tdx.c      |  7 +++++++
 target/i386/kvm/tdx.h      |  1 +
 5 files changed, 29 insertions(+), 8 deletions(-)

Patch

diff --git a/hw/i386/pc_sysfw.c b/hw/i386/pc_sysfw.c
index bdec29fd9519..fbe3e42278cd 100644
--- a/hw/i386/pc_sysfw.c
+++ b/hw/i386/pc_sysfw.c
@@ -147,8 +147,8 @@  static void pc_system_flash_map(PCMachineState *pcms,
     int64_t size;
     PFlashCFI01 *system_flash;
     MemoryRegion *flash_mem;
-    void *flash_ptr;
-    int flash_size;
+    void *flash_ptr[2] = {NULL, NULL};
+    int flash_size[2];
     int ret;
 
     assert(PC_MACHINE_GET_CLASS(pcms)->pci_enabled);
@@ -197,29 +197,29 @@  static void pc_system_flash_map(PCMachineState *pcms,
                             0x100000000ULL - total_size);
         }
 
+        flash_ptr[i] = memory_region_get_ram_ptr(flash_mem);
+        flash_size[i] = memory_region_size(flash_mem);
         if (i == 0) {
             pc_isa_bios_init(rom_memory, flash_mem, size);
 
-            flash_ptr = memory_region_get_ram_ptr(flash_mem);
-            flash_size = memory_region_size(flash_mem);
             /*
              * OVMF places a GUIDed structures in the flash, so
              * search for them
              */
-            pc_system_parse_ovmf_flash(flash_ptr, flash_size);
+            pc_system_parse_ovmf_flash(flash_ptr[i], flash_size[i]);
 
             /* Encrypt the pflash boot ROM */
             if (sev_enabled()) {
 
-                ret = sev_es_save_reset_vector(flash_ptr, flash_size);
+                ret = sev_es_save_reset_vector(flash_ptr[i], flash_size[i]);
                 if (ret) {
                     error_report("failed to locate and/or save reset vector");
                     exit(1);
                 }
 
-                sev_encrypt_flash(flash_ptr, flash_size, &error_fatal);
+                sev_encrypt_flash(flash_ptr[i], flash_size[i], &error_fatal);
             } else if (is_tdx_vm()) {
-                ret = tdx_parse_tdvf(flash_ptr, flash_size);
+                ret = tdx_parse_tdvf(flash_ptr[i], flash_size[i]);
                 if (ret) {
                     error_report("failed to parse TDVF in pflash for TDX VM");
                     exit(1);
@@ -227,6 +227,10 @@  static void pc_system_flash_map(PCMachineState *pcms,
             }
         }
     }
+
+    if (is_tdx_vm()) {
+        tdx_set_code_vars_ptr(flash_ptr[0], flash_ptr[1]);
+    }
 }
 
 void pc_system_firmware_init(PCMachineState *pcms,
diff --git a/include/hw/i386/tdvf.h b/include/hw/i386/tdvf.h
index 593341eb2e93..773bd39a3bff 100644
--- a/include/hw/i386/tdvf.h
+++ b/include/hw/i386/tdvf.h
@@ -42,6 +42,10 @@  typedef struct TdxFirmwareEntry {
 } TdxFirmwareEntry;
 
 typedef struct TdxFirmware {
+    bool split_tdvf;
+    void *code_ptr;
+    void *vars_ptr;
+
     uint32_t nr_entries;
     TdxFirmwareEntry *entries;
 } TdxFirmware;
diff --git a/target/i386/kvm/tdx-stub.c b/target/i386/kvm/tdx-stub.c
index 395a59721266..b548b4578276 100644
--- a/target/i386/kvm/tdx-stub.c
+++ b/target/i386/kvm/tdx-stub.c
@@ -17,3 +17,8 @@  int tdx_parse_tdvf(void *flash_ptr, int size)
 {
     return -EINVAL;
 }
+
+void tdx_set_code_vars_ptr(void *code_ptr, void *vars_ptr)
+{
+    g_assert_not_reached();
+}
diff --git a/target/i386/kvm/tdx.c b/target/i386/kvm/tdx.c
index 7f34b14dc504..cd88b6dfc280 100644
--- a/target/i386/kvm/tdx.c
+++ b/target/i386/kvm/tdx.c
@@ -265,6 +265,13 @@  int tdx_parse_tdvf(void *flash_ptr, int size)
     return tdvf_parse_metadata(&tdx_guest->tdvf, flash_ptr, size);
 }
 
+void tdx_set_code_vars_ptr(void *code_ptr, void *vars_ptr)
+{
+    tdx_guest->tdvf.code_ptr = code_ptr;
+    tdx_guest->tdvf.vars_ptr = vars_ptr;
+    tdx_guest->tdvf.split_tdvf = vars_ptr ? true : false;
+}
+
 static bool tdx_guest_get_sept_ve_disable(Object *obj, Error **errp)
 {
     TdxGuest *tdx = TDX_GUEST(obj);
diff --git a/target/i386/kvm/tdx.h b/target/i386/kvm/tdx.h
index 12bcf25bb95b..b3cedd0d5d0c 100644
--- a/target/i386/kvm/tdx.h
+++ b/target/i386/kvm/tdx.h
@@ -37,5 +37,6 @@  void tdx_get_supported_cpuid(uint32_t function, uint32_t index, int reg,
                              uint32_t *ret);
 int tdx_pre_create_vcpu(CPUState *cpu);
 int tdx_parse_tdvf(void *flash_ptr, int size);
+void tdx_set_code_vars_ptr(void *code_ptr, void *vars_ptr);
 
 #endif /* QEMU_I386_TDX_H */