[PATCH v3 42/70] i386/tdx: Track mem_ptr for each firmware entry of TDVF

Xiaoyao Li
2023-11-15T07:21:07Z

For each TDVF sections, QEMU needs to copy the content to guest
private memory via KVM API (KVM_TDX_INIT_MEM_REGION).

Introduce a field @mem_ptr for TdxFirmwareEntry to track the memory
pointer of each TDVF sections. So that QEMU can add/copy them to guest
private memory later.

TDVF sections can be classified into two groups:
- Firmware itself, e.g., TDVF BFV and CFV, that located separately from
guest RAM. Its memory pointer is the bios pointer.

- Sections located at guest RAM, e.g., TEMP_MEM and TD_HOB.
mmap a new memory range for them.

Register a machine_init_done callback to do the stuff.

Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
---
hw/i386/tdvf.c | 1 +
include/hw/i386/tdvf.h | 7 +++++++
target/i386/kvm/tdx.c | 31 +++++++++++++++++++++++++++++++
3 files changed, 39 insertions(+)

diff --git a/hw/i386/tdvf.c b/hw/i386/tdvf.c
index ff51f40088f0..0a6445705160 100644
--- a/hw/i386/tdvf.c
+++ b/hw/i386/tdvf.c
@@ -189,6 +189,7 @@ int tdvf_parse_metadata(TdxFirmware *fw, void *flash_ptr, int size)
}
g_free(sections);

+ fw->mem_ptr = flash_ptr;
return 0;

err:
diff --git a/include/hw/i386/tdvf.h b/include/hw/i386/tdvf.h
index 593341eb2e93..d880af245a73 100644
--- a/include/hw/i386/tdvf.h
+++ b/include/hw/i386/tdvf.h
@@ -39,13 +39,20 @@ typedef struct TdxFirmwareEntry {
uint64_t size;
uint32_t type;
uint32_t attributes;
+
+ void *mem_ptr;
} TdxFirmwareEntry;

typedef struct TdxFirmware {
+ void *mem_ptr;
+
uint32_t nr_entries;
TdxFirmwareEntry *entries;
} TdxFirmware;

+#define for_each_tdx_fw_entry(fw, e) \
+ for (e = (fw)->entries; e != (fw)->entries + (fw)->nr_entries; e++)
+
int tdvf_parse_metadata(TdxFirmware *fw, void *flash_ptr, int size);

#endif /* HW_I386_TDVF_H */
diff --git a/target/i386/kvm/tdx.c b/target/i386/kvm/tdx.c
index cfe623fdd4e6..03c7f7ab2720 100644
--- a/target/i386/kvm/tdx.c
+++ b/target/i386/kvm/tdx.c
@@ -14,6 +14,7 @@
#include "qemu/osdep.h"
#include "qemu/error-report.h"
#include "qemu/base64.h"
+#include "qemu/mmap-alloc.h"
#include "qapi/error.h"
#include "qom/object_interfaces.h"
#include "standard-headers/asm-x86/kvm_para.h"
@@ -22,6 +23,7 @@
#include "exec/address-spaces.h"

#include "hw/i386/x86.h"
+#include "hw/i386/tdvf.h"
#include "kvm_i386.h"
#include "tdx.h"
#include "../cpu-internal.h"
@@ -457,6 +459,33 @@ static void update_tdx_cpuid_lookup_by_tdx_caps(void)
(tdx_caps->xfam_fixed1 & CPUID_XSTATE_XSS_MASK) >> 32;
}

+static void tdx_finalize_vm(Notifier *notifier, void *unused)
+{
+ TdxFirmware *tdvf = &tdx_guest->tdvf;
+ TdxFirmwareEntry *entry;
+
+ for_each_tdx_fw_entry(tdvf, entry) {
+ switch (entry->type) {
+ case TDVF_SECTION_TYPE_BFV:
+ case TDVF_SECTION_TYPE_CFV:
+ entry->mem_ptr = tdvf->mem_ptr + entry->data_offset;
+ break;
+ case TDVF_SECTION_TYPE_TD_HOB:
+ case TDVF_SECTION_TYPE_TEMP_MEM:
+ entry->mem_ptr = qemu_ram_mmap(-1, entry->size,
+ qemu_real_host_page_size(), 0, 0);
+ break;
+ default:
+ error_report("Unsupported TDVF section %d", entry->type);
+ exit(1);
+ }
+ }
+}
+
+static Notifier tdx_machine_done_notify = {
+ .notify = tdx_finalize_vm,
+};
+
int tdx_kvm_init(MachineState *ms, Error **errp)
{
TdxGuest *tdx = TDX_GUEST(OBJECT(ms->cgs));
@@ -482,6 +511,8 @@ int tdx_kvm_init(MachineState *ms, Error **errp)
*/
kvm_readonly_mem_allowed = false;

+ qemu_add_machine_init_done_notifier(&tdx_machine_done_notify);
+
tdx_guest = tdx;
return 0;
}
--
2.34.1