[PATCH 8/9] i386/sev: Implement ConfidentialGuestSupport functions for SEV

[Roy Hopkins <roy.hopkins@suse.com>]

The ConfidentialGuestSupport object defines a number of virtual
functions that are called during processing of IGVM directives to query
or configure initial guest state. In order to support processing of IGVM
files, these functions need to be implemented by relevant isolation
hardware support code such as SEV.

This commit implements the required functions for SEV-ES and adds
support for processing IGVM files for configuring the guest.

Signed-off-by: Roy Hopkins <roy.hopkins@suse.com>
---
 target/i386/sev.c | 77 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 77 insertions(+)

diff --git a/target/i386/sev.c b/target/i386/sev.c
index d6902432fd..b85ccff9db 100644
--- a/target/i386/sev.c
+++ b/target/i386/sev.c
@@ -37,6 +37,7 @@
 #include "qapi/qapi-commands-misc-target.h"
 #include "exec/confidential-guest-support.h"
 #include "hw/i386/pc.h"
+#include "hw/i386/e820_memory_layout.h"
 #include "exec/address-spaces.h"
 
 #define TYPE_SEV_GUEST "sev-guest"
@@ -170,6 +171,9 @@ static const char *const sev_fw_errlist[] = {
 
 #define SEV_FW_MAX_ERROR      ARRAY_SIZE(sev_fw_errlist)
 
+static int sev_launch_update_data(SevGuestState *sev_guest, uint8_t *addr,
+                                  uint64_t len);
+
 static int
 sev_ioctl(int fd, int cmd, void *data, int *error)
 {
@@ -304,6 +308,14 @@ sev_guest_finalize(Object *obj)
 {
 }
 
+static int cgs_check_support(ConfidentialGuestPlatformType platform,
+                             uint16_t platform_version, uint8_t highest_vtl,
+                             uint64_t shared_gpa_boundary)
+{
+    return (((platform == CGS_PLATFORM_SEV_ES) && sev_es_enabled()) ||
+            ((platform == CGS_PLATFORM_SEV) && sev_enabled())) ? 1 : 0;
+}
+
 static void sev_apply_cpu_context(CPUState *cpu)
 {
     SevGuestState *sev_guest = SEV_GUEST(MACHINE(qdev_get_machine())->cgs);
@@ -447,6 +459,65 @@ static int sev_set_cpu_context(uint16_t cpu_index, const void *ctx,
     return 0;
 }
 
+static int cgs_set_guest_state(hwaddr gpa, uint8_t *ptr, uint64_t len,
+                               ConfidentialGuestPageType memory_type,
+                               uint16_t cpu_index)
+{
+    SevGuestState *sev = SEV_GUEST(MACHINE(qdev_get_machine())->cgs);
+    int ret = 1;
+
+    if (!sev_enabled()) {
+        error_report("%s: attempt to configure guest memory, but SEV "
+                     "is not enabled",
+                     __func__);
+    } else if (memory_type == CGS_PAGE_TYPE_VMSA) {
+        if (!sev_es_enabled()) {
+            error_report("%s: attempt to configure initial VMSA, but SEV-ES "
+                         "is not supported",
+                         __func__);
+        } else {
+            ret = sev_set_cpu_context(cpu_index, ptr, len, gpa);
+        }
+    } else if ((memory_type != CGS_PAGE_TYPE_REQUIRED_MEMORY) &&
+               (memory_type != CGS_PAGE_TYPE_UNMEASURED)) {
+        ret = sev_launch_update_data(sev, ptr, len);
+    } else {
+        error_report(
+            "%s: attempted to configure guest memory to use memory_type %d, "
+            "but this type is not supported by SEV-ES",
+            __func__, (int)memory_type);
+    }
+    return ret;
+}
+
+static int cgs_get_mem_map_entry(int index,
+                                  ConfidentialGuestMemoryMapEntry *entry)
+{
+    if ((index < 0) || (index >= e820_get_num_entries())) {
+        return 1;
+    }
+    entry->gpa = e820_table[index].address;
+    entry->size = e820_table[index].length;
+    switch (e820_table[index].type) {
+    case E820_RAM:
+        entry->type = CGS_MEM_RAM;
+        break;
+    case E820_RESERVED:
+        entry->type = CGS_MEM_RESERVED;
+        break;
+    case E820_ACPI:
+        entry->type = CGS_MEM_ACPI;
+        break;
+    case E820_NVS:
+        entry->type = CGS_MEM_NVS;
+        break;
+    case E820_UNUSABLE:
+        entry->type = CGS_MEM_UNUSABLE;
+        break;
+    }
+    return 0;
+}
+
 static char *
 sev_guest_get_session_file(Object *obj, Error **errp)
 {
@@ -538,6 +609,7 @@ static void
 sev_guest_instance_init(Object *obj)
 {
     SevGuestState *sev = SEV_GUEST(obj);
+    ConfidentialGuestSupport *cgs = CONFIDENTIAL_GUEST_SUPPORT(obj);
 
     sev->sev_device = g_strdup(DEFAULT_SEV_DEVICE);
     sev->policy = DEFAULT_GUEST_POLICY;
@@ -550,6 +622,11 @@ sev_guest_instance_init(Object *obj)
     object_property_add_uint32_ptr(obj, "reduced-phys-bits",
                                    &sev->reduced_phys_bits,
                                    OBJ_PROP_FLAG_READWRITE);
+
+    cgs->check_support = cgs_check_support;
+    cgs->set_guest_state = cgs_set_guest_state;
+    cgs->get_mem_map_entry = cgs_get_mem_map_entry;
+
     QTAILQ_INIT(&sev->launch_vmsa);
 }
 
-- 
2.43.0