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

[Wen Congyang]

At 03/24/2011 09:31 AM, KAMEZAWA Hiroyuki Write:
>>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;
> +        }
> +    }

Do not report error when qemuDomainAssignPCIAddresses() or virDomainDefAddImplicitControllers()
failed, because we have reported the error in these functions.

> +    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"));