[PATCH v6 2/6] qemu: Add command-line to generate SGX EPC memory backend

[Haibin Huang <haibin.huang@xxxxxxxxx>]

From: Lin Yang <lin.a.yang@xxxxxxxxx>

According to the result parsing from xml, add the argument of
SGX EPC memory backend into QEMU command line:

    #qemu-system-x86_64 \
        ...... \
        -object memory-backend-epc,id=mem1,size=64M,prealloc=on \
        -object memory-backend-epc,id=mem2,size=28M \
        -M sgx-epc.0.memdev=mem1,sgx-epc.1.memdev=mem2
---
 src/qemu/qemu_alias.c   |  8 +++++---
 src/qemu/qemu_command.c | 41 +++++++++++++++++++++++++++++++++++++----
 src/qemu/qemu_domain.c  |  8 +++++++-
 3 files changed, 49 insertions(+), 8 deletions(-)

diff --git a/src/qemu/qemu_alias.c b/src/qemu/qemu_alias.c
index 101ab5608f..d935ae6847 100644
--- a/src/qemu/qemu_alias.c
+++ b/src/qemu/qemu_alias.c
@@ -487,10 +487,12 @@ qemuAssignDeviceMemoryAlias(virDomainDefPtr def,
 
     if (mem->model == VIR_DOMAIN_MEMORY_MODEL_DIMM)
         prefix = "dimm";
-    else
+    else if (mem->model == VIR_DOMAIN_MEMORY_MODEL_NVDIMM)
         prefix = "nvdimm";
+    else
+        prefix = "epc";
 
-    if (oldAlias) {
+    if (oldAlias || mem->model == VIR_DOMAIN_MEMORY_MODEL_SGX_EPC) {
         for (i = 0; i < def->nmems; i++) {
             if ((idx = qemuDomainDeviceAliasIndex(&def->mems[i]->info, prefix)) >= maxidx)
                 maxidx = idx + 1;
@@ -674,7 +676,7 @@ qemuAssignDeviceAliases(virDomainDefPtr def, virQEMUCapsPtr qemuCaps)
             return -1;
     }
     for (i = 0; i < def->nmems; i++) {
-        if (qemuAssignDeviceMemoryAlias(NULL, def->mems[i], false) < 0)
+        if (qemuAssignDeviceMemoryAlias(def, def->mems[i], false) < 0)
             return -1;
     }
     if (def->vsock) {
diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index 4a1d0c3e9e..dba76d3f78 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -3143,6 +3143,14 @@ qemuBuildMemoryBackendProps(virJSONValuePtr *backendProps,
 
         if (qemuBuildMemoryBackendPropsShare(props, memAccess) < 0)
             return -1;
+    } else if (mem->model == VIR_DOMAIN_MEMORY_MODEL_SGX_EPC) {
+        backendType = "memory-backend-epc";
+        if (!priv->memPrealloc)
+            prealloc = true;
+        if (virJSONValueObjectAdd(props,
+                                  "B:prealloc", prealloc,
+                                  NULL) < 0)
+            return -1;
     } else {
         backendType = "memory-backend-ram";
     }
@@ -7477,6 +7485,8 @@ qemuBuildMemoryDeviceCommandLine(virCommandPtr cmd,
                                  qemuDomainObjPrivatePtr priv)
 {
     size_t i;
+    g_auto(virBuffer) epcBuf = VIR_BUFFER_INITIALIZER;
+    int epcNum = 0;
 
     /* memory hotplug requires NUMA to be enabled - we already checked
      * that memory devices are present only when NUMA is */
@@ -7490,12 +7500,35 @@ qemuBuildMemoryDeviceCommandLine(virCommandPtr cmd,
         virCommandAddArg(cmd, "-object");
         virCommandAddArgBuffer(cmd, &buf);
 
-        if (!(dimmStr = qemuBuildMemoryDeviceStr(def->mems[i], priv)))
-            return -1;
+        switch ((virDomainMemoryModel) def->mems[i]->model) {
+        case VIR_DOMAIN_MEMORY_MODEL_NVDIMM:
+        case VIR_DOMAIN_MEMORY_MODEL_DIMM:
+            if (!(dimmStr = qemuBuildMemoryDeviceStr(def->mems[i], priv)))
+                return -1;
+
+            virCommandAddArgList(cmd, "-device", dimmStr, NULL);
+
+            VIR_FREE(dimmStr);
+            break;
+
+        case VIR_DOMAIN_MEMORY_MODEL_SGX_EPC:
+            if (virBufferUse(&epcBuf) > 0)
+                virBufferAddChar(&epcBuf, ',');
+
+            virBufferAsprintf(&epcBuf, "sgx-epc.%d.memdev=%s", epcNum++,
+                              g_strdup_printf("mem%s", def->mems[i]->info.alias));
+
+            break;
 
-        virCommandAddArgList(cmd, "-device", dimmStr, NULL);
+        case VIR_DOMAIN_MEMORY_MODEL_NONE:
+        case VIR_DOMAIN_MEMORY_MODEL_LAST:
+            break;
+        }
+    }
 
-        VIR_FREE(dimmStr);
+    if (virBufferUse(&epcBuf) > 0) {
+        virCommandAddArg(cmd, "-M");
+        virCommandAddArgBuffer(cmd, &epcBuf);
     }
 
     return 0;
diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c
index 55c874da16..d9e2da5f70 100644
--- a/src/qemu/qemu_domain.c
+++ b/src/qemu/qemu_domain.c
@@ -8430,7 +8430,7 @@ qemuDomainDefValidateMemoryHotplug(const virDomainDef *def,
                                    virQEMUCapsPtr qemuCaps,
                                    const virDomainMemoryDef *mem)
 {
-    unsigned int nmems = def->nmems;
+    unsigned int nmems = 0;
     unsigned long long hotplugSpace;
     unsigned long long hotplugMemory = 0;
     bool needPCDimmCap = false;
@@ -8439,6 +8439,12 @@ qemuDomainDefValidateMemoryHotplug(const virDomainDef *def,
 
     hotplugSpace = def->mem.max_memory - virDomainDefGetMemoryInitial(def);
 
+    for (i = 0; i < def->nmems; i++) {
+        if (def->mems[i]->model == VIR_DOMAIN_MEMORY_MODEL_DIMM ||
+            def->mems[i]->model == VIR_DOMAIN_MEMORY_MODEL_NVDIMM)
+            nmems++;
+    }
+
     if (mem) {
         nmems++;
         hotplugMemory = mem->size;
-- 
2.17.1