[PATCH v4 30/33] qmp: Add the qmp_query_sgx_capabilities()

[Yang Zhong <yang.zhong@intel.com>]

Libvirt can use qmp_query_sgx_capabilities() to get the host
sgx capabilities.

Signed-off-by: Yang Zhong <yang.zhong@intel.com>

v1-->v2:
   - Changed the blurb error and "Since: 5.1" to "Since: 6.1"(Eric Blake).
---
 hw/i386/sgx.c              | 66 ++++++++++++++++++++++++++++++++++++++
 include/hw/i386/pc.h       |  1 +
 monitor/qmp-cmds.c         |  5 +++
 qapi/misc.json             | 19 +++++++++++
 stubs/sgx-stub.c           |  5 +++
 tests/qtest/qmp-cmd-test.c |  1 +
 6 files changed, 97 insertions(+)

diff --git a/hw/i386/sgx.c b/hw/i386/sgx.c
index beff7e3cf0..993e885980 100644
--- a/hw/i386/sgx.c
+++ b/hw/i386/sgx.c
@@ -17,6 +17,72 @@
 #include "monitor/qdev.h"
 #include "qapi/error.h"
 #include "exec/address-spaces.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              GENMASK(3, 0)
+
+static uint64_t sgx_calc_section_metric(uint64_t low, uint64_t high)
+{
+    return (low & GENMASK_ULL(31, 12)) +
+           ((high & GENMASK_ULL(19, 0)) << 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(void)
 {
diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h
index de351ec48a..6f687e62bc 100644
--- a/include/hw/i386/pc.h
+++ b/include/hw/i386/pc.h
@@ -207,6 +207,7 @@ void pc_machine_init_sgx_epc(PCMachineState *pcms);
 void sgx_memory_backend_reset(HostMemoryBackend *backend, int fd,
                               Error **errp);
 SGXInfo *sgx_get_info(void);
+SGXInfo *sgx_get_capabilities(Error **errp);
 
 extern GlobalProperty pc_compat_5_2[];
 extern const size_t pc_compat_5_2_len;
diff --git a/monitor/qmp-cmds.c b/monitor/qmp-cmds.c
index 48f7708ffe..f1360e9f4e 100644
--- a/monitor/qmp-cmds.c
+++ b/monitor/qmp-cmds.c
@@ -365,3 +365,8 @@ SGXInfo *qmp_query_sgx(Error **errp)
 
     return info;
 }
+
+SGXInfo *qmp_query_sgx_capabilities(Error **errp)
+{
+    return sgx_get_capabilities(errp);
+}
diff --git a/qapi/misc.json b/qapi/misc.json
index 83b45a1460..8d1a78d138 100644
--- a/qapi/misc.json
+++ b/qapi/misc.json
@@ -561,3 +561,22 @@
 #
 ##
 { 'command': 'query-sgx', 'returns': 'SGXInfo' }
+
+
+##
+# @query-sgx-capabilities:
+#
+# Returns information from host SGX capabilities
+#
+# Returns: @SGXInfo
+#
+# Since: 6.1
+#
+# Example:
+#
+# -> { "execute": "query-sgx-capabilities" }
+# <- { "return": { "sgx": true, "sgx1" : true, "sgx2" : true,
+#                  "flc": true, "section-size" : 0 } }
+#
+##
+{ 'command': 'query-sgx-capabilities', 'returns': 'SGXInfo' }
diff --git a/stubs/sgx-stub.c b/stubs/sgx-stub.c
index c2b59a88fd..1dedf3f3db 100644
--- a/stubs/sgx-stub.c
+++ b/stubs/sgx-stub.c
@@ -5,3 +5,8 @@ SGXInfo *sgx_get_info(void)
 {
     return NULL;
 }
+
+SGXInfo *sgx_get_capabilities(Error **errp)
+{
+    return NULL;
+}
diff --git a/tests/qtest/qmp-cmd-test.c b/tests/qtest/qmp-cmd-test.c
index b75f3364f3..1af2f74c28 100644
--- a/tests/qtest/qmp-cmd-test.c
+++ b/tests/qtest/qmp-cmd-test.c
@@ -101,6 +101,7 @@ static bool query_is_ignored(const char *cmd)
         "query-sev",
         "query-sev-capabilities",
         "query-sgx",
+        "query-sgx-capabilities",
         NULL
     };
     int i;