My apologies to all,
This patch depends on my previous patch (seperate blktap1/blktap2 disk
types). I should have sent them out together.
Thanks,
Ryan
On Thu, Jul 02, 2009 at 11:35:47PM -0700, Ryan O'Connor wrote:
> # HG changeset patch
> # User Ryan O'Connor <rjo@xxxxxxxxx>
> # Date 1246602456 25200
> # Node ID 2292564d6029d5a3fc6b57d51059e2bd5e0dfbec
> # Parent 6b489d139da0dd3bd4a1f673816559acf9b0a9e0
> blktap2: fix save/restore/migration
>
> blktap2 devices use a regular 'phy' vbd blkback backend, causing
> Blktap2Controller to trample the devices' parameters. This causes problems
> with
> save/restore and managed domains, among other things. This patch modifies
> Blktap2Controller to store both the vbd and tap2 parameters in xenstore, and
> stops it from trampling the device's config on device creation.
>
> * store blktap2 parameters in xenstore
> * restore blktap2 device config to original state once the underlying vbd
> device is created (this fixes managed domains)
> * use blktap2 parameters rather than vbd parameters when building blktap2
> device configurations
> * remove blktap2 specific code from XendConfig
>
> Signed-off-by: Ryan O'Connor <rjo@xxxxxxxxx>
>
> diff -r 6b489d139da0 -r 2292564d6029 tools/python/xen/xend/XendConfig.py
> --- a/tools/python/xen/xend/XendConfig.py Thu Jul 02 23:27:33 2009 -0700
> +++ b/tools/python/xen/xend/XendConfig.py Thu Jul 02 23:27:36 2009 -0700
> @@ -1120,8 +1120,6 @@ class XendConfig(dict):
> if sxp.child_value(config, 'bootable',
> None) is None:
> is_bootable =
> dev_cfg.get('bootable', 0)
> config.append(['bootable',
> int(is_bootable)])
> - if dev_cfg.has_key('required_uname'):
> - config.append(['required_uname',
> dev_cfg['required_uname']])
> config.append(['VDI', dev_cfg.get('VDI',
> '')])
>
> sxpr.append(['device', config])
> @@ -1372,13 +1370,6 @@ class XendConfig(dict):
> dev_info['driver'] = 'paravirtualised'
>
> if dev_type == 'tap' or dev_type == 'tap2':
> - if dev_info.has_key('required_uname'):
> - # Restore uname by required_uname because uname might
> - # be replaced with 'phy:/dev/xen/blktap-2/tapdev*'.
> - dev_info['uname'] = dev_info['required_uname']
> - else:
> - # Save uname for next domain start.
> - dev_info['required_uname'] = dev_info['uname']
> tap_disk_type = dev_info['uname'].split(':')[1]
> # tapdisk uname may be 'tap:<driver>' or
> 'tap:tapdisk:<driver>'
> if tap_disk_type == 'tapdisk':
> diff -r 6b489d139da0 -r 2292564d6029
> tools/python/xen/xend/server/BlktapController.py
> --- a/tools/python/xen/xend/server/BlktapController.py Thu Jul 02
> 23:27:33 2009 -0700
> +++ b/tools/python/xen/xend/server/BlktapController.py Thu Jul 02
> 23:27:36 2009 -0700
> @@ -137,10 +137,39 @@ class Blktap2Controller(BlktapController
> deviceClass,
> self.vm.getDomid(), devid)
>
> + def getDeviceDetails(self, config):
> +
> + (devid, back, front) = BlktapController.getDeviceDetails(self,
> config)
> + if self.deviceClass == 'tap2':
> + # since blktap2 uses blkback as a backend the 'params' feild contains
> + # the path to the blktap2 device (/dev/xen/blktap-2/tapdev*). As
> well,
> + # we need to store the params used to create the blktap2 device
> + # (tap:tapdisk:<driver>:/<image-path>)
> + tapdisk_uname = config.get('tapdisk_uname', '')
> + (_, tapdisk_params) = string.split(tapdisk_uname, ':', 1)
> + back['tapdisk-params'] = tapdisk_params
> +
> + return (devid, back, front)
> +
> + def getDeviceConfiguration(self, devid, transaction = None):
> +
> + # this is a blktap2 device, so we need to overwrite the 'params'
> feild
> + # with the actual blktap2 parameters. (the vbd parameters are of
> little
> + # use to us)
> + config = BlktapController.getDeviceConfiguration(self, devid,
> transaction)
> + if transaction is None:
> + tapdisk_params = self.readBackend(devid, 'tapdisk-params')
> + else:
> + tapdisk_params = self.readBackendTxn(transaction, devid,
> 'tapdisk-params')
> + if tapdisk_params:
> + config['uname'] = 'tap:' + tapdisk_params
> +
> + return config
> +
>
> def createDevice(self, config):
>
> - uname = config.get('required_uname', '')
> + uname = config.get('uname', '')
> try:
> (typ, subtyp, params, file) = string.split(uname, ':', 3)
> except:
> @@ -180,11 +209,15 @@ class Blktap2Controller(BlktapController
> stdout.close();
> stderr.close();
>
> - #modify the configuration to attach as a vbd, now that the
> - #device is configured. Then continue to create the device
> + # modify the configutration to create a blkback for the underlying
> + # blktap2 device. Note: we need to preserve the original tapdisk
> uname
> + # (it is used during save/restore and for managed domains).
> + config.update({'tapdisk_uname' : uname})
> config.update({'uname' : 'phy:' + device.rstrip()})
>
> devid = BlkifController.createDevice(self, config)
> + config.update({'uname' : uname})
> + config.pop('tapdisk_uname')
> return devid
>
> # The new blocktap implementation requires a sysfs signal to close
>
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@xxxxxxxxxxxxxxxxxxx
> http://lists.xensource.com/xen-devel
--
Ryan O'Connor <rjo@xxxxxxxxx>
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel
|
Home