target/i386: Add the query-sgx-capabilities QMP command
Libvirt can use query-sgx-capabilities to get the host
sgx capabilities to decide how to allocate SGX EPC size to VM.
Signed-off-by: Yang Zhong <yang.zhong@intel.com>
Message-Id: <20210910102258.46648-3-yang.zhong@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/hw/i386/sgx-stub.c b/hw/i386/sgx-stub.c
index 485e16e..3be9f5c 100644
--- a/hw/i386/sgx-stub.c
+++ b/hw/i386/sgx-stub.c
@@ -9,6 +9,12 @@
return NULL;
}
+SGXInfo *sgx_get_capabilities(Error **errp)
+{
+ error_setg(errp, "SGX support is not compiled in");
+ return NULL;
+}
+
void pc_machine_init_sgx_epc(PCMachineState *pcms)
{
memset(&pcms->sgx_epc, 0, sizeof(SGXEPCState));
diff --git a/hw/i386/sgx.c b/hw/i386/sgx.c
index ea75398..e481e93 100644
--- a/hw/i386/sgx.c
+++ b/hw/i386/sgx.c
@@ -18,6 +18,72 @@
#include "qapi/error.h"
#include "exec/address-spaces.h"
#include "hw/i386/sgx.h"
+#include "sysemu/hw_accel.h"
+
+#define SGX_MAX_EPC_SECTIONS 8
+#define SGX_CPUID_EPC_INVALID 0x0
+
+/* A valid EPC section. */
+#define SGX_CPUID_EPC_SECTION 0x1
+#define SGX_CPUID_EPC_MASK 0xF
+
+static uint64_t sgx_calc_section_metric(uint64_t low, uint64_t high)
+{
+ return (low & MAKE_64BIT_MASK(12, 20)) +
+ ((high & MAKE_64BIT_MASK(0, 20)) << 32);
+}
+
+static uint64_t sgx_calc_host_epc_section_size(void)
+{
+ uint32_t i, type;
+ uint32_t eax, ebx, ecx, edx;
+ uint64_t size = 0;
+
+ for (i = 0; i < SGX_MAX_EPC_SECTIONS; i++) {
+ host_cpuid(0x12, i + 2, &eax, &ebx, &ecx, &edx);
+
+ type = eax & SGX_CPUID_EPC_MASK;
+ if (type == SGX_CPUID_EPC_INVALID) {
+ break;
+ }
+
+ if (type != SGX_CPUID_EPC_SECTION) {
+ break;
+ }
+
+ size += sgx_calc_section_metric(ecx, edx);
+ }
+
+ return size;
+}
+
+SGXInfo *sgx_get_capabilities(Error **errp)
+{
+ SGXInfo *info = NULL;
+ uint32_t eax, ebx, ecx, edx;
+
+ int fd = qemu_open_old("/dev/sgx_vepc", O_RDWR);
+ if (fd < 0) {
+ error_setg(errp, "SGX is not enabled in KVM");
+ return NULL;
+ }
+
+ info = g_new0(SGXInfo, 1);
+ host_cpuid(0x7, 0, &eax, &ebx, &ecx, &edx);
+
+ info->sgx = ebx & (1U << 2) ? true : false;
+ info->flc = ecx & (1U << 30) ? true : false;
+
+ host_cpuid(0x12, 0, &eax, &ebx, &ecx, &edx);
+ info->sgx1 = eax & (1U << 0) ? true : false;
+ info->sgx2 = eax & (1U << 1) ? true : false;
+
+ info->section_size = sgx_calc_host_epc_section_size();
+
+ close(fd);
+
+ return info;
+}
SGXInfo *sgx_get_info(Error **errp)
{
diff --git a/include/hw/i386/sgx.h b/include/hw/i386/sgx.h
index 2bf90b3..16fc257 100644
--- a/include/hw/i386/sgx.h
+++ b/include/hw/i386/sgx.h
@@ -7,5 +7,6 @@
#include "qapi/qapi-types-misc-target.h"
SGXInfo *sgx_get_info(Error **errp);
+SGXInfo *sgx_get_capabilities(Error **errp);
#endif
diff --git a/qapi/misc-target.json b/qapi/misc-target.json
index e2a347c..594fbd1 100644
--- a/qapi/misc-target.json
+++ b/qapi/misc-target.json
@@ -376,3 +376,21 @@
#
##
{ 'command': 'query-sgx', 'returns': 'SGXInfo', 'if': 'TARGET_I386' }
+
+##
+# @query-sgx-capabilities:
+#
+# Returns information from host SGX capabilities
+#
+# Returns: @SGXInfo
+#
+# Since: 6.2
+#
+# Example:
+#
+# -> { "execute": "query-sgx-capabilities" }
+# <- { "return": { "sgx": true, "sgx1" : true, "sgx2" : true,
+# "flc": true, "section-size" : 0 } }
+#
+##
+{ 'command': 'query-sgx-capabilities', 'returns': 'SGXInfo', 'if': 'TARGET_I386' }
diff --git a/target/i386/monitor.c b/target/i386/monitor.c
index d7384ba..196c1c9 100644
--- a/target/i386/monitor.c
+++ b/target/i386/monitor.c
@@ -790,3 +790,8 @@
monitor_printf(mon, "size: %" PRIu64 "\n",
info->section_size);
}
+
+SGXInfo *qmp_query_sgx_capabilities(Error **errp)
+{
+ return sgx_get_capabilities(errp);
+}
diff --git a/tests/qtest/qmp-cmd-test.c b/tests/qtest/qmp-cmd-test.c
index b75f336..1af2f74 100644
--- a/tests/qtest/qmp-cmd-test.c
+++ b/tests/qtest/qmp-cmd-test.c
@@ -101,6 +101,7 @@
"query-sev",
"query-sev-capabilities",
"query-sgx",
+ "query-sgx-capabilities",
NULL
};
int i;
