[libvirt] [PATCH 4/5] libvirt/qemu - support modification of disks in inactive domain

[Wen Congyang]

At 03/03/2011 09:12 AM, KAMEZAWA Hiroyuki Write:
>>From 8d2544bc773a2222c8aa1fdfc5cade20d8c1e958 Mon Sep 17 00:00:00 2001
> From: KAMEZAWA Hiroyuki <kamezawa.hiroyu at jp.fujitsu.com>
> Date: Thu, 3 Mar 2011 09:53:08 +0900
> Subject: [PATCH 4/5] libvirt/qemu - support modification of disks in inactive domain
> 
> This patch adds support for persistent modification of disks in
> inactive domain.
> 
> Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu at jp.fujitsu.com>
> ---
>  src/qemu/qemu_driver.c |   42 ++++++++++++++++++++++++++++++++++++++++++
>  1 files changed, 42 insertions(+), 0 deletions(-)
> 
> diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
> index 3248cdc..4df6bf9 100644
> --- a/src/qemu/qemu_driver.c
> +++ b/src/qemu/qemu_driver.c
> @@ -4099,6 +4099,18 @@ cleanup:
>      return ret;
>  }
>  
> +static int qemuDomainFindDiskByName(virDomainDefPtr vmdef, const char *name)
> +{
> +    virDomainDiskDefPtr vdisk;
> +    int i;
> +
> +    for (i = 0; i < vmdef->ndisks; i++) {
> +        vdisk = vmdef->disks[i];
> +        if (STREQ(vdisk->dst, name))
> +            return i;
> +    }
> +    return -1;
> +}

This function can be moved into src/conf/domain_conf.c, and it may be used by other
driver if this driver supports attach/detach device into inactive domain.

>  /*
>   * Attach a device given by XML, the change will be persistent
>   * and domain XML definition file is updated.
> @@ -4106,9 +4118,26 @@ cleanup:
>  static int qemuDomainAttachDevicePersistent(virDomainDefPtr vmdef,
>                                              virDomainDeviceDefPtr newdev)
>  {
> +    virDomainDiskDefPtr disk;
>  
>      /* At first, check device confliction */
>      switch(newdev->type) {
> +    case VIR_DOMAIN_DEVICE_DISK:
> +        disk = newdev->data.disk;
> +        if (qemuDomainFindDiskByName(vmdef, disk->dst) >= 0) {
> +            qemuReportError(VIR_ERR_INVALID_ARG,
> +                 _("target %s already exists."), disk->dst);
> +            return -1;
> +        }
> +
> +        if (virDomainDiskInsert(vmdef, disk)) /* only failed with OOM */
> +            return -1;
> +
> +        if (disk->bus == VIR_DOMAIN_DISK_BUS_VIRTIO &&
> +            qemuDomainAssignPCIAddresses(vmdef) < 0)
> +                return -1;

Use virDomainDefAddImplicitControllers() to add any implied controllers
which aren't present and used by attached disk.

> +        newdev->data.disk = NULL;
> +        break;
>      default:
>          qemuReportError(VIR_ERR_INVALID_ARG, "%s",
>                          _("Sorry, the device is not suppored for now"));
> @@ -4121,7 +4150,20 @@ static int qemuDomainAttachDevicePersistent(virDomainDefPtr vmdef,
>  static int qemuDomainDetachDevicePersistent(virDomainDefPtr vmdef,
>                                         virDomainDeviceDefPtr device)
>  {
> +    int x;
> +    virDomainDiskDefPtr disk;
> +
>      switch(device->type) {
> +    case VIR_DOMAIN_DEVICE_DISK:
> +        disk = device->data.disk;
> +        x = qemuDomainFindDiskByName(vmdef, disk->dst);
> +        if (x < 0) {
> +            qemuReportError(VIR_ERR_INVALID_ARG,
> +                 _("target %s doesn't exist."), disk->dst);
> +            return -1;
> +        }
> +        virDomainDiskRemove(vmdef, x);
> +        break;
>      default:
>          qemuReportError(VIR_ERR_INVALID_ARG, "%s",
>                          _("Sorry, the device is not suppored for now"));