[libvirt] [PATCHv6 2/3] libvirt/qemu - support persistent modification of qemu disks

[KAMEZAWA Hiroyuki]

>From 1d2630896a950b87043c9e77fdbcdc23626098ee Mon Sep 17 00:00:00 2001
From: KAMEZAWA Hiroyuki <kamezawa.hiroyu at jp.fujitsu.com>
Date: Thu, 24 Mar 2011 10:05:18 +0900
Subject: [PATCHv6 2/3] libvirt/qemu - support persistent modification of qemu disks

support changes of disks by VIR_DOMAIN_DEVICE_MODIFY_CONFIG
for qemu.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu at jp.fujitsu.com>

Changelog v5->v6:
  - fixed pci address/device controller assign failure case.

Changelog v4->v5:
  - moved some functions to domain_conf.c
  - added virDomainDefAddImplicitControllers() for ide/scsi
  - report OOM.
  - clean up.
---
 src/conf/domain_conf.c   |   22 +++++++++++++++++++
 src/conf/domain_conf.h   |    3 +-
 src/libvirt_private.syms |    2 +
 src/qemu/qemu_driver.c   |   51 +++++++++++++++++++++++++++++++++++++++++++++-
 4 files changed, 76 insertions(+), 2 deletions(-)

diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index c637300..1bf8fbe 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -4859,6 +4859,19 @@ virVirtualPortProfileFormat(virBufferPtr buf,
     virBufferVSprintf(buf, "%s</virtualport>\n", indent);
 }
 
+int virDomainDiskIndexByName(virDomainDefPtr def, const char *name)
+{
+    virDomainDiskDefPtr vdisk;
+    int i;
+
+    for (i = 0; i < def->ndisks; i++) {
+        vdisk = def->disks[i];
+        if (STREQ(vdisk->dst, name))
+            return i;
+    }
+    return -1;
+}
+
 int virDomainDiskInsert(virDomainDefPtr def,
                         virDomainDiskDefPtr disk)
 {
@@ -4930,6 +4943,15 @@ void virDomainDiskRemove(virDomainDefPtr def, size_t i)
     }
 }
 
+int virDomainDiskRemoveByName(virDomainDefPtr def, const char *name)
+{
+    int i = virDomainDiskIndexByName(def, name);
+    if (i < 0)
+        return -1;
+    virDomainDiskRemove(def, i);
+    return 0;
+}
+
 
 int virDomainControllerInsert(virDomainDefPtr def,
                               virDomainControllerDefPtr controller)
diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h
index cbd0f98..236ad04 100644
--- a/src/conf/domain_conf.h
+++ b/src/conf/domain_conf.h
@@ -1258,7 +1258,7 @@ int virDomainCpuSetParse(const char **str,
                          int maxcpu);
 char *virDomainCpuSetFormat(char *cpuset,
                             int maxcpu);
-
+int virDomainDiskIndexByName(virDomainDefPtr def, const char *name);
 int virDomainDiskInsert(virDomainDefPtr def,
                         virDomainDiskDefPtr disk);
 void virDomainDiskInsertPreAlloced(virDomainDefPtr def,
@@ -1266,6 +1266,7 @@ void virDomainDiskInsertPreAlloced(virDomainDefPtr def,
 int virDomainDiskDefAssignAddress(virCapsPtr caps, virDomainDiskDefPtr def);
 
 void virDomainDiskRemove(virDomainDefPtr def, size_t i);
+int virDomainDiskRemoveByName(virDomainDefPtr def, const char *name);
 
 int virDomainControllerInsert(virDomainDefPtr def,
                               virDomainControllerDefPtr controller);
diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
index 55be36e..9ced196 100644
--- a/src/libvirt_private.syms
+++ b/src/libvirt_private.syms
@@ -243,11 +243,13 @@ virDomainDiskDefFree;
 virDomainDiskDeviceTypeToString;
 virDomainDiskErrorPolicyTypeFromString;
 virDomainDiskErrorPolicyTypeToString;
+virDomainDiskIndexByName;
 virDomainDiskInsert;
 virDomainDiskInsertPreAlloced;
 virDomainDiskIoTypeFromString;
 virDomainDiskIoTypeToString;
 virDomainDiskRemove;
+virDomainDiskRemoveByName;
 virDomainDiskTypeFromString;
 virDomainDiskTypeToString;
 virDomainFSDefFree;
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 468361b..386b654 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -4140,6 +4140,24 @@ cleanup:
     return ret;
 }
 
+static int qemuDomainDeviceAddressFixup(virDomainDefPtr vmdef, bool pci)
+{
+    if (pci) {
+        if (qemuDomainAssignPCIAddresses(vmdef)) {
+            qemuReportError(VIR_ERR_INVALID_ARG, "%s",
+                            _("device or domain PCI addresses."));
+            return -1;
+        }
+    } else {
+        if (virDomainDefAddImplicitControllers(vmdef) < 0) {
+            qemuReportError(VIR_ERR_INVALID_ARG, "%s",
+                            _("device address or domain device controllers."));
+            return -1;
+        }
+    }
+    return 0;
+}
+
 /*
  * Attach a device given by XML, the change will be persistent
  * and domain XML definition file is updated.
@@ -4147,21 +4165,52 @@ cleanup:
 static int qemuDomainAttachDevicePersistent(virDomainDefPtr vmdef,
                                             virDomainDeviceDefPtr newdev)
 {
+    virDomainDiskDefPtr disk;
+    bool pci;
+    int ret;
 
     switch(newdev->type) {
+    case VIR_DOMAIN_DEVICE_DISK:
+        disk = newdev->data.disk;
+        if (virDomainDiskIndexByName(vmdef, disk->dst) >= 0) {
+            qemuReportError(VIR_ERR_INVALID_ARG,
+                            _("target %s already exists."), disk->dst);
+            return -1;
+        }
+        if (virDomainDiskInsert(vmdef, disk)) {
+            virReportOOMError();
+            return -1;
+        }
+        pci = (disk->bus == VIR_DOMAIN_DISK_BUS_VIRTIO);
+        ret = qemuDomainDeviceAddressFixup(vmdef, pci);
+        if (ret < 0)
+            virDomainDiskRemoveByName(vmdef, disk->dst);
+        else
+            newdev->data.disk = NULL;
+        break;
     default:
         qemuReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
                         _("Sorry, the device is not supported for now"));
         return -1;
     }
 
-    return 0;
+    return ret;
 }
 
 static int qemuDomainDetachDevicePersistent(virDomainDefPtr vmdef,
                                             virDomainDeviceDefPtr device)
 {
+    virDomainDiskDefPtr disk;
+
     switch(device->type) {
+    case VIR_DOMAIN_DEVICE_DISK:
+        disk = device->data.disk;
+        if (virDomainDiskRemoveByName(vmdef, disk->dst)) {
+            qemuReportError(VIR_ERR_INVALID_ARG,
+                            _("no target device %s"), disk->dst);
+            return -1;
+        }
+        break;
     default:
         qemuReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
                         _("Sorry, the device is not supported for now"));
-- 
1.7.4.1