[v5,36/65] i386/tdx: load TDVF for TD guest

Commit Message

Xiaoyao Li Feb. 29, 2024, 6:36 a.m. UTC

From: Chao Peng <[e-mail]>

TDVF(OVMF) needs to run at private memory for TD guest. TDX cannot
support pflash device since it doesn't support read-only private memory.
Thus load TDVF(OVMF) with -bios option for TDs.

Use memory_region_init_ram_guest_memfd() to allocate the MemoryRegion
for TDVF because it needs to be located at private memory.

Also store the MemoryRegion pointer of TDVF since the shared ramblock of
it can be discared after it gets copied to private ramblock.

Signed-off-by: Chao Peng <[e-mail]>
Co-developed-by: Xiaoyao Li <[e-mail]>
Signed-off-by: Xiaoyao Li <[e-mail]>
---
 hw/i386/x86.c         | 13 +++++++++++--
 target/i386/kvm/tdx.c |  7 +++++++
 target/i386/kvm/tdx.h |  3 +++
 3 files changed, 21 insertions(+), 2 deletions(-)

Patch

diff --git a/hw/i386/x86.c b/hw/i386/x86.c
index fa7095310f37..5a0cadc88c4f 100644
--- a/hw/i386/x86.c
+++ b/hw/i386/x86.c
@@ -47,6 +47,7 @@ 
 #include "hw/intc/i8259.h"
 #include "hw/rtc/mc146818rtc.h"
 #include "target/i386/sev.h"
+#include "kvm/tdx.h"
 
 #include "hw/acpi/cpu_hotplug.h"
 #include "hw/irq.h"
@@ -1157,9 +1158,17 @@  void x86_bios_rom_init(MachineState *ms, const char *default_firmware,
         (bios_size % 65536) != 0) {
         goto bios_error;
     }
+
     bios = g_malloc(sizeof(*bios));
-    memory_region_init_ram(bios, NULL, "pc.bios", bios_size, &error_fatal);
-    if (sev_enabled()) {
+    if (is_tdx_vm()) {
+        memory_region_init_ram_guest_memfd(bios, NULL, "pc.bios", bios_size,
+                                           &error_fatal);
+        tdx_set_tdvf_region(bios);
+    } else {
+        memory_region_init_ram(bios, NULL, "pc.bios", bios_size, &error_fatal);
+    }
+
+    if (sev_enabled() || is_tdx_vm()) {
         /*
          * The concept of a "reset" simply doesn't exist for
          * confidential computing guests, we have to destroy and
diff --git a/target/i386/kvm/tdx.c b/target/i386/kvm/tdx.c
index 13f069171db7..7c8e14e3cc58 100644
--- a/target/i386/kvm/tdx.c
+++ b/target/i386/kvm/tdx.c
@@ -19,6 +19,7 @@ 
 #include "standard-headers/asm-x86/kvm_para.h"
 #include "sysemu/kvm.h"
 #include "sysemu/sysemu.h"
+#include "exec/ramblock.h"
 
 #include "hw/i386/x86.h"
 #include "kvm_i386.h"
@@ -463,6 +464,12 @@  static void update_tdx_cpuid_lookup_by_tdx_caps(void)
             (tdx_caps->xfam_fixed1 & CPUID_XSTATE_XSS_MASK) >> 32;
 }
 
+void tdx_set_tdvf_region(MemoryRegion *tdvf_mr)
+{
+    assert(!tdx_guest->tdvf_mr);
+    tdx_guest->tdvf_mr = tdvf_mr;
+}
+
 static int tdx_kvm_init(ConfidentialGuestSupport *cgs, Error **errp)
 {
     MachineState *ms = MACHINE(qdev_get_machine());
diff --git a/target/i386/kvm/tdx.h b/target/i386/kvm/tdx.h
index 2697e6bdfb1d..c021223001a5 100644
--- a/target/i386/kvm/tdx.h
+++ b/target/i386/kvm/tdx.h
@@ -24,6 +24,8 @@  typedef struct TdxGuest {
     char *mrconfigid;       /* base64 encoded sha348 digest */
     char *mrowner;          /* base64 encoded sha348 digest */
     char *mrownerconfig;    /* base64 encoded sha348 digest */
+
+    MemoryRegion *tdvf_mr;
 } TdxGuest;
 
 #ifdef CONFIG_TDX
@@ -35,5 +37,6 @@  bool is_tdx_vm(void);
 void tdx_get_supported_cpuid(uint32_t function, uint32_t index, int reg,
                              uint32_t *ret);
 int tdx_pre_create_vcpu(CPUState *cpu, Error **errp);
+void tdx_set_tdvf_region(MemoryRegion *tdvf_mr);
 
 #endif /* QEMU_I386_TDX_H */