[libvirt] [PATCHv5 3/3] libvirt/qemu - support support persistent modification of qemu interfaces

[Wen Congyang]

At 03/16/2011 02:46 PM, KAMEZAWA Hiroyuki Write:
>>From d69f7c07571c8adfc7720aab77aa1f103eb6e95b Mon Sep 17 00:00:00 2001
> From: KAMEZAWA Hiroyuki <kamezawa.hiroyu at jp.fujitsu.com>
> Date: Wed, 16 Mar 2011 15:39:14 +0900
> Subject: [PATCHv5 3/3] libvirt/qemu - support support persistent modification of qemu interfaces.
> 
>  support changes of interfaces by VIR_DOMAIN_DEVICE_MODIFY_CONFIG
>  for qemu.
> 
>  Changelog v4->v5
>    - fixed mac handling.
>    - moved some functions to domain_conf.c
>    - clean up.
> 
> Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu at jp.fujitsu.com>
> ---
>  src/conf/domain_conf.c   |   56 ++++++++++++++++++++++++++++++++++++++++++++++
>  src/conf/domain_conf.h   |    5 ++++
>  src/libvirt_private.syms |    4 +++
>  src/qemu/qemu_driver.c   |   38 +++++++++++++++++++++++++++++++
>  4 files changed, 103 insertions(+), 0 deletions(-)
> 
> diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
> index 1d39481..9e4dea6 100644
> --- a/src/conf/domain_conf.c
> +++ b/src/conf/domain_conf.c
> @@ -4952,6 +4952,62 @@ int virDomainDiskRemoveByName(virDomainDefPtr def, const char *name)
>      return 0;
>  }
>  
> +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;
> +}
> +
> +int virDomainNetIndexByMac(virDomainDefPtr def, const unsigned char*mac)
> +{
> +    int i;
> +
> +    for (i = 0; i < def->nnets; i++)
> +        if (memcmp(def->nets[i]->mac, mac, VIR_MAC_BUFLEN))
> +            return i;
> +    return -1;
> +}
> +
> +int virDomainNetIndexByIfname(virDomainDefPtr def, const char*name)
> +{
> +    int i;
> +
> +    for (i = 0; i < def->nnets; i++) {
> +        if (def->nets[i]->ifname && STREQ(def->nets[i]->ifname, name))
> +            return i;
> +    }
> +    return -1;
> +}
> +
> +static 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 virDomainNetRemoveByMac(virDomainDefPtr def, const unsigned char *mac)
> +{
> +    int i;
> +
> +    i = virDomainNetIndexByMac(def, mac);
> +    if (i < 0)
> +        return -1;
> +    virDomainNetRemove(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 320ca13..d5154f6 100644
> --- a/src/conf/domain_conf.h
> +++ b/src/conf/domain_conf.h
> @@ -1271,6 +1271,11 @@ int virDomainDiskDefAssignAddress(virCapsPtr caps, virDomainDiskDefPtr def);
>  void virDomainDiskRemove(virDomainDefPtr def, size_t i);
>  int virDomainDiskRemoveByName(virDomainDefPtr def, const char *name);
>  
> +int virDomainNetIndexByIfname(virDomainDefPtr def, const char *ifname);
> +int virDomainNetIndexByMac(virDomainDefPtr def, const unsigned char *mac);
> +int virDomainNetInsert(virDomainDefPtr dev, virDomainNetDefPtr net);
> +int virDomainNetRemoveByMac(virDomainDefPtr def, const unsigned char *mac);
> +
>  int virDomainControllerInsert(virDomainDefPtr def,
>                                virDomainControllerDefPtr controller);
>  void virDomainControllerInsertPreAlloced(virDomainDefPtr def,
> diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
> index 1761dfb..cdc63db 100644
> --- a/src/libvirt_private.syms
> +++ b/src/libvirt_private.syms
> @@ -277,6 +277,10 @@ virDomainMemballoonModelTypeFromString;
>  virDomainMemballoonModelTypeToString;
>  virDomainNetDefFree;
>  virDomainNetTypeToString;
> +virDomainNetIndexByIfname;
> +virDomainNetIndexByMac;
> +virDomainNetInsert;
> +virDomainNetRemoveByMac;
>  virDomainObjAssignDef;
>  virDomainObjSetDefTransient;
>  virDomainObjGetPersistentDef;
> diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
> index d6d7ad0..45b1bf0 100644
> --- a/src/qemu/qemu_driver.c
> +++ b/src/qemu/qemu_driver.c
> @@ -4138,6 +4138,7 @@ static int qemuDomainAttachDevicePersistent(virDomainDefPtr vmdef,
>                                              virDomainDeviceDefPtr newdev)
>  {
>      virDomainDiskDefPtr disk;
> +    virDomainNetDefPtr net;
>  
>      switch(newdev->type) {
>      case VIR_DOMAIN_DEVICE_DISK:
> @@ -4158,6 +4159,31 @@ static int qemuDomainAttachDevicePersistent(virDomainDefPtr vmdef,
>              return -1;
>          newdev->data.disk = NULL;
>          break;
> +    case VIR_DOMAIN_DEVICE_NET:
> +        net = newdev->data.net;
> +        /* check mac */
> +        if (virDomainNetIndexByMac(vmdef, net->mac) >= 0) {
> +            char macbuf[VIR_MAC_STRING_BUFLEN];
> +
> +            virFormatMacAddr(net->mac, macbuf);
> +            qemuReportError(VIR_ERR_INVALID_ARG,
> +                            _("target mac %s already exists."), macbuf);
> +            return -1;
> +        }
> +        /* Sanity check : test ifname confliction. */
> +        if (net->ifname && virDomainNetIndexByIfname(vmdef, net->ifname) >= 0) {
> +            qemuReportError(VIR_ERR_INVALID_ARG,
> +                            _("target NIC %s already exists."), net->ifname);
> +            return -1;
> +        }
> +        if (virDomainNetInsert(vmdef, net)) {
> +            virReportOOMError();
> +            return -1;
> +        }
> +        if (qemuDomainAssignPCIAddresses(vmdef) < 0)
> +            return -1;

When qemuDomainAssignPCIAddresses() failed, we should remove net from vmdef,
otherwise, it will cause libvirtd crashed.

> +        newdev->data.net = NULL;
> +        break;
>      default:
>          qemuReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
>                          _("Sorry, the device is not supported for now"));
> @@ -4171,6 +4197,7 @@ static int qemuDomainDetachDevicePersistent(virDomainDefPtr vmdef,
>                                              virDomainDeviceDefPtr device)
>  {
>      virDomainDiskDefPtr disk;
> +    virDomainNetDefPtr net;
>  
>      switch(device->type) {
>      case VIR_DOMAIN_DEVICE_DISK:
> @@ -4181,6 +4208,17 @@ static int qemuDomainDetachDevicePersistent(virDomainDefPtr vmdef,
>              return -1;
>          }
>          break;
> +    case VIR_DOMAIN_DEVICE_NET:
> +        net = device->data.net;
> +        if (virDomainNetRemoveByMac(vmdef, net->mac)) {
> +            char macbuf[VIR_MAC_STRING_BUFLEN];
> +
> +            virFormatMacAddr(net->mac, macbuf);
> +            qemuReportError(VIR_ERR_INVALID_ARG,
> +                            _("no interface with mac %s"), macbuf);
> +            return -1;
> +        }
> +        break;
>      default:
>          qemuReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
>                          _("Sorry, the device is not supported for now"));