From f173f6a79c759b5d286940f5a58d43f38366ebae Mon Sep 17 00:00:00 2001
From: Michal Privoznik <mprivozn@redhat.com>
Date: Mon, 27 Feb 2023 10:58:27 +0100
Subject: [PATCH] qemu_monitor: Switch to virDomainMemoryModel enum in
 qemuMonitorJSONGetMemoryDeviceInfo()

When processing memory devices (as a reply from QEMU), a bunch of
STREQ()-s is used. Fortunately, the set of strings we process is
the same as virDomainMemoryModel enum. Therefore, we can use
virDomainMemoryModelTypeFromString() and then use integer
comparison (well, switch()). This has an upside: introducing a
new memory model lets us see what places need adjusting
immediately at compile time.

NB, this is in contrast with cmd line generator
(qemuBuildMemoryDeviceProps()), where more specific models are
generated (e.g. "pc-dimm", "virtio-mem-pci", etc.). But QEMU
reports back the parent model, instead of specific child
instance.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Kristina Hanicova <khanicov@redhat.com>
---
 src/qemu/qemu_monitor_json.c | 54 +++++++++++++++++++++++++-----------
 1 file changed, 38 insertions(+), 16 deletions(-)

diff --git a/src/qemu/qemu_monitor_json.c b/src/qemu/qemu_monitor_json.c
index d76fea8b00..5ed1f9442e 100644
--- a/src/qemu/qemu_monitor_json.c
+++ b/src/qemu/qemu_monitor_json.c
@@ -7210,16 +7210,22 @@ qemuMonitorJSONGetMemoryDeviceInfo(qemuMonitor *mon,
         virJSONValue *elem = virJSONValueArrayGet(data, i);
         g_autofree qemuMonitorMemoryDeviceInfo *meminfo = NULL;
         virJSONValue *dimminfo;
-        const char *devalias;
-        const char *type;
+        const char *devalias = NULL;
+        const char *modelStr;
+        int model;
 
-        if (!(type = virJSONValueObjectGetString(elem, "type"))) {
+        if (!(modelStr = virJSONValueObjectGetString(elem, "type"))) {
             virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                            _("query-memory-devices reply data doesn't contain "
                              "enum type discriminator"));
             return -1;
         }
 
+        if ((model = virDomainMemoryModelTypeFromString(modelStr)) < 0) {
+            VIR_WARN("Unknown memory model: %s", modelStr);
+            continue;
+        }
+
         if (!(dimminfo = virJSONValueObjectGetObject(elem, "data"))) {
             virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                            _("query-memory-devices reply data doesn't "
@@ -7227,30 +7233,40 @@ qemuMonitorJSONGetMemoryDeviceInfo(qemuMonitor *mon,
             return -1;
         }
 
-        if (STREQ(type, "dimm") || STREQ(type, "nvdimm") || STREQ(type, "virtio-mem")) {
+        switch ((virDomainMemoryModel) model) {
+        case VIR_DOMAIN_MEMORY_MODEL_DIMM:
+        case VIR_DOMAIN_MEMORY_MODEL_NVDIMM:
+        case VIR_DOMAIN_MEMORY_MODEL_VIRTIO_MEM:
             /* While 'id' attribute is marked as optional in QEMU's QAPI
-            * specification, Libvirt always sets it. Thus we can fail if not
-            * present. */
+             * specification, Libvirt always sets it. Thus we can fail if not
+             * present. */
             if (!(devalias = virJSONValueObjectGetString(dimminfo, "id"))) {
                 virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
-                            _("dimm memory info data is missing 'id'"));
+                               _("dimm memory info data is missing 'id'"));
                 return -1;
             }
-        } else if (STREQ(type, "sgx-epc")) {
+            break;
+
+        case VIR_DOMAIN_MEMORY_MODEL_SGX_EPC:
             if (!(devalias = virJSONValueObjectGetString(dimminfo, "memdev"))) {
                 virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
-                            _("sgx-epc memory info data is missing 'memdev'"));
+                               _("sgx-epc memory info data is missing 'memdev'"));
                 return -1;
             }
-        } else {
+            break;
+
+        case VIR_DOMAIN_MEMORY_MODEL_VIRTIO_PMEM:
+        case VIR_DOMAIN_MEMORY_MODEL_NONE:
+        case VIR_DOMAIN_MEMORY_MODEL_LAST:
             /* type not handled yet */
             continue;
         }
 
         meminfo = g_new0(qemuMonitorMemoryDeviceInfo, 1);
 
-        /* dimm memory devices */
-        if (STREQ(type, "dimm") || STREQ(type, "nvdimm")) {
+        switch ((virDomainMemoryModel) model) {
+        case VIR_DOMAIN_MEMORY_MODEL_DIMM:
+        case VIR_DOMAIN_MEMORY_MODEL_NVDIMM:
             if (virJSONValueObjectGetNumberUlong(dimminfo, "addr",
                                                  &meminfo->address) < 0) {
                 virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
@@ -7280,16 +7296,18 @@ qemuMonitorJSONGetMemoryDeviceInfo(qemuMonitor *mon,
                 return -1;
 
             }
+            break;
 
-        } else if (STREQ(type, "virtio-mem")) {
+        case VIR_DOMAIN_MEMORY_MODEL_VIRTIO_MEM:
             if (virJSONValueObjectGetNumberUlong(dimminfo, "size",
                                                  &meminfo->size) < 0) {
                 virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                                _("malformed/missing size in virtio memory info"));
                 return -1;
             }
-        } else if (STREQ(type, "sgx-epc")) {
-            /* sgx-epc memory devices */
+            break;
+
+        case VIR_DOMAIN_MEMORY_MODEL_SGX_EPC:
             if (virJSONValueObjectGetNumberUlong(dimminfo, "memaddr",
                                                  &meminfo->address) < 0) {
                 virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
@@ -7303,7 +7321,11 @@ qemuMonitorJSONGetMemoryDeviceInfo(qemuMonitor *mon,
                                _("malformed/missing size in sgx-epc memory info"));
                 return -1;
             }
-        } else {
+            break;
+
+        case VIR_DOMAIN_MEMORY_MODEL_VIRTIO_PMEM:
+        case VIR_DOMAIN_MEMORY_MODEL_NONE:
+        case VIR_DOMAIN_MEMORY_MODEL_LAST:
             /* type not handled yet */
             continue;
         }