[libvirt] [PATCH 2/2] libvirt/qemu : allow persistent modification of netifs via A(De)ttachDeviceFlags

[KAMEZAWA Hiroyuki]

>From 3307d7228ea3c47884d626584db646d23a5a22ce Mon Sep 17 00:00:00 2001
From: KAMEZAWA Hiroyuki <kamezawa at bluextal.(none)>
Date: Wed, 23 Feb 2011 17:25:07 +0900
Subject: [PATCH 2/2] libvirt/qemu : allow persistent modification of netifs via A(De)ttachDeviceFlags

This patch allows virsh attach/detach-interface --persistent...
with qemu. Xen supports this behavior now.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu at jp.fujitsu.com>
---
 src/conf/domain_conf.c   |   25 ++++++++++++++++++++
 src/conf/domain_conf.h   |    3 ++
 src/libvirt_private.syms |    2 +
 src/qemu/qemu_driver.c   |   57 ++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 87 insertions(+), 0 deletions(-)

diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index b97c1f0..dcbf756 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -4924,6 +4924,31 @@ void virDomainDiskRemove(virDomainDefPtr def, size_t i)
     }
 }
 
+int virDomainNetInsert(virDomainDefPtr def, virDomainNetDefPtr net)
+{
+   if (VIR_REALLOC_N(def->nets, def->nnets) < 0)
+       return -1;
+   def->nets[def->nnets] = net;
+   def->nnets++;
+   return 0;
+}
+
+void virDomainNetRemove(virDomainDefPtr def, size_t i)
+{
+    if (def->nnets > 1) {
+        memmove(def->nets + i,
+                def->nets + i + 1,
+                sizeof(*def->nets) * (def->nnets - (i + 1)));
+        def->nnets--;
+        if (VIR_REALLOC_N(def->nets, def->nnets) < 0) {
+            /* ignore harmless */
+        }
+    } else {
+        VIR_FREE(def->nets);
+        def->nnets = 0;
+    }
+}
+
 
 int virDomainControllerInsert(virDomainDefPtr def,
                               virDomainControllerDefPtr controller)
diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h
index 30aeccc..396dfbc 100644
--- a/src/conf/domain_conf.h
+++ b/src/conf/domain_conf.h
@@ -1270,6 +1270,9 @@ int virDomainDiskDefAssignAddress(virCapsPtr caps, virDomainDiskDefPtr def);
 
 void virDomainDiskRemove(virDomainDefPtr def, size_t i);
 
+void virDomainNetInsert(virDomainDefPtr def, virDomainNetDefPtr net);
+void virDomainNetRemove(virDomainDefPtr def, size_t i);
+
 int virDomainControllerInsert(virDomainDefPtr def,
                               virDomainControllerDefPtr controller);
 void virDomainControllerInsertPreAlloced(virDomainDefPtr def,
diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
index 797a670..eef5266 100644
--- a/src/libvirt_private.syms
+++ b/src/libvirt_private.syms
@@ -245,6 +245,8 @@ virDomainDiskIoTypeToString;
 virDomainDiskRemove;
 virDomainDiskTypeFromString;
 virDomainDiskTypeToString;
+virDomainNetInsert;
+virDomainNetRemove;
 virDomainFSDefFree;
 virDomainFindByID;
 virDomainFindByName;
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 703f86a..ab697cd 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -4094,6 +4094,22 @@ static int qemuDomainFindDiskByName(virDomainDefPtr vmdef, const char *name)
     }
     return -1;
 }
+
+static int qemuDomainFindNetByName(virDomainDefPtr vmdef,
+	const unsigned char *mac, const char *ifname)
+{
+    virDomainNetDefPtr net;
+    int i;
+
+    for (i = 0; i < vmdef->nnets; i++) {
+        net = vmdef->nets[i];
+        if (!strcmp((char*)net->mac, (char*)mac))
+             return i;
+        if (ifname && !strcmp((char*)net->ifname, (char*)ifname))
+             return i;
+    }
+    return -1;
+}
 /*
  * Attach a device given by XML, the change will be persistent
  * and domain XML definition file is updated.
@@ -4102,6 +4118,7 @@ static int qemuDomainAttachDevicePersistent(virDomainDefPtr vmdef,
                                             virDomainDeviceDefPtr newdev)
 {
     virDomainDiskDefPtr disk;
+    virDomainNetDefPtr net;
 
     /* At first, check device confliction */
     switch(newdev->type) {
@@ -4128,6 +4145,22 @@ static int qemuDomainAttachDevicePersistent(virDomainDefPtr vmdef,
         }
         newdev->data.disk = NULL;
         break;
+    case VIR_DOMAIN_DEVICE_NET:
+        net = newdev->data.net;
+        if (qemuDomainFindNetByName(vmdef, net->mac, net->ifname) >= 0) {
+            qemuReportError(VIR_ERR_INVALID_ARG,
+                 _("target %s already exists."), disk->dst);
+            return -1;
+        }
+
+        if (virDomainNetInsert(vmdef, net)) {
+            virReportOOMError();
+            return -1;
+        }
+        /* always PCI ? */
+        qemuDomainAssignPCIAddresses(vmdef);
+        newdev->data.net = NULL;
+        break;
     default:
         qemuReportError(VIR_ERR_INVALID_ARG, "%s",
                         _("Sorry, the device is not suppored for now"));
@@ -4142,6 +4175,7 @@ static int qemuDomainDetachDevicePersistent(virDomainDefPtr vmdef,
 {
     int x;
     virDomainDiskDefPtr disk;
+    virDomainNetDefPtr net;
 
     switch(device->type) {
     case VIR_DOMAIN_DEVICE_DISK:
@@ -4154,6 +4188,29 @@ static int qemuDomainDetachDevicePersistent(virDomainDefPtr vmdef,
         }
         virDomainDiskRemove(vmdef, x);
         break;
+    case VIR_DOMAIN_DEVICE_NET:
+        net = device->data.net;
+        /* need to find mac address */
+        if (net->ifname == NULL && strlen((char*)net->mac) == 0) {
+            qemuReportError(VIR_ERR_INVALID_ARG, "%s",
+                    _("interface mac or name must be specified."));
+            return -1;
+        }
+        net = device->data.net;
+        x = qemuDomainFindNetByName(vmdef, net->mac, net->ifname);
+        if (x < 0) {
+	    if (net->ifname)
+	    	qemuReportError(VIR_ERR_INVALID_ARG,
+                    _("interface mac: %s name: %s doesn't exist."),
+		    net->mac, net->ifname);
+            else
+	    	qemuReportError(VIR_ERR_INVALID_ARG,
+		    _("interface mac: %s doesn't exist."),
+                    net->mac);
+            return -1;
+        }
+        virDomainNetRemove(vmdef, x);
+        break;
     default:
         qemuReportError(VIR_ERR_INVALID_ARG, "%s",
                         _("Sorry, the device is not suppored for now"));
-- 
1.7.1