From b25b071c7551495882cb8970bccd3e31d16b3667 Mon Sep 17 00:00:00 2001
From: Zheng Yan <yanzheng759@huawei.com>
Date: Tue, 11 May 2021 22:05:20 +0800
Subject: [PATCH] libvirt: Introduce virDomainGraphicsReload API
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The new virDomainGraphicsReload API is used to make the domain reload
its certificates without restart, and avoid service interruption.

Currently, only QEMU VNC TLS certificates are supported, but
flags are also reserved for subsequent scenarios.

To reload QEMU VNC TLS certificates as an example, we can call:

  virDomainGraphicsReload(domain, 0, 0);

Then the specified QMP message would be send to QEMU:
{"execute": "display-reload", "arguments":{"type": "vnc", "tls-certs": true}}

Signed-off-by: Zheng Yan <yanzheng759@huawei.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
---
 include/libvirt/libvirt-domain.h | 18 +++++++++++++
 src/driver-hypervisor.h          |  6 +++++
 src/libvirt-domain.c             | 44 ++++++++++++++++++++++++++++++++
 src/libvirt_public.syms          |  5 ++++
 4 files changed, 73 insertions(+)

diff --git a/include/libvirt/libvirt-domain.h b/include/libvirt/libvirt-domain.h
index 30cce85b29..2f5b01bbfe 100644
--- a/include/libvirt/libvirt-domain.h
+++ b/include/libvirt/libvirt-domain.h
@@ -6507,4 +6507,22 @@ int virDomainFDAssociate(virDomainPtr domain,
                          int *fds,
                          unsigned int flags);
 
+/**
+ * virDomainGraphicsReloadType:
+ *
+ * Since: 10.2.0
+ */
+typedef enum {
+    VIR_DOMAIN_GRAPHICS_RELOAD_TYPE_ANY = 0, /* reload any graphics known to libvirt (Since: 10.2.0) */
+    VIR_DOMAIN_GRAPHICS_RELOAD_TYPE_VNC = 1, /* reload vnc graphics (Since: 10.2.0) */
+# ifdef VIR_ENUM_SENTINELS
+    VIR_DOMAIN_GRAPHICS_RELOAD_TYPE_LAST /* (Since: 10.2.0) */
+# endif
+} virDomainGraphicsReloadType;
+
+int
+virDomainGraphicsReload(virDomainPtr domain,
+                        unsigned int type,
+                        unsigned int flags);
+
 #endif /* LIBVIRT_DOMAIN_H */
diff --git a/src/driver-hypervisor.h b/src/driver-hypervisor.h
index 5219344b72..4ce8da078d 100644
--- a/src/driver-hypervisor.h
+++ b/src/driver-hypervisor.h
@@ -1448,6 +1448,11 @@ typedef int
                            int *fds,
                            unsigned int flags);
 
+typedef int
+(*virDrvDomainGraphicsReload)(virDomainPtr domain,
+                              unsigned int type,
+                              unsigned int flags);
+
 typedef struct _virHypervisorDriver virHypervisorDriver;
 
 /**
@@ -1720,4 +1725,5 @@ struct _virHypervisorDriver {
     virDrvDomainGetMessages domainGetMessages;
     virDrvDomainStartDirtyRateCalc domainStartDirtyRateCalc;
     virDrvDomainFDAssociate domainFDAssociate;
+    virDrvDomainGraphicsReload domainGraphicsReload;
 };
diff --git a/src/libvirt-domain.c b/src/libvirt-domain.c
index 83abad251e..9e3c61b66a 100644
--- a/src/libvirt-domain.c
+++ b/src/libvirt-domain.c
@@ -14118,3 +14118,47 @@ virDomainFDAssociate(virDomainPtr domain,
     virDispatchError(conn);
     return -1;
 }
+
+
+/**
+ * virDomainGraphicsReload:
+ * @domain: a domain object
+ * @type: graphics type; from the virDomainGraphicsReloadType enum
+ * @flags: extra flags; not used yet, so callers should always pass 0
+ *
+ * Reload domain's graphics. This can be used to reload TLS certificates
+ * without restarting the domain.
+ *
+ * Returns 0 in case of success, -1 otherwise.
+ *
+ * Since: 10.2.0
+ */
+int
+virDomainGraphicsReload(virDomainPtr domain,
+                        unsigned int type,
+                        unsigned int flags)
+{
+    virConnectPtr conn;
+
+    VIR_DOMAIN_DEBUG(domain, "type=%u, flags=0x%x", type, flags);
+
+    virResetLastError();
+
+    virCheckDomainReturn(domain, -1);
+    conn = domain->conn;
+    virCheckReadOnlyGoto(conn->flags, error);
+
+    if (conn->driver->domainGraphicsReload) {
+        int ret;
+        ret = conn->driver->domainGraphicsReload(domain, type, flags);
+        if (ret < 0)
+            goto error;
+        return ret;
+    }
+
+    virReportUnsupportedError();
+
+ error:
+    virDispatchError(domain->conn);
+    return -1;
+}
diff --git a/src/libvirt_public.syms b/src/libvirt_public.syms
index 0304b8f824..7a3492d9d7 100644
--- a/src/libvirt_public.syms
+++ b/src/libvirt_public.syms
@@ -943,4 +943,9 @@ LIBVIRT_10.1.0 {
         virNodeDeviceUpdate;
 } LIBVIRT_9.7.0;
 
+LIBVIRT_10.2.0 {
+    global:
+        virDomainGraphicsReload;
+} LIBVIRT_10.1.0;
+
 # .... define new API here using predicted next version number ....