<div dir="ltr"><div>Thank you, I see your point. We could just ignore the 'enabled' attribute from the reconnect element</div><div>when it's used in the NBD source context:</div><div> </div><div><source protocol='nbd' name='foo'> </div><div> <host name='<a href="http://example.org" rel="noreferrer" target="_blank">example.org</a> <<a href="http://example.org" rel="noreferrer" target="_blank">http://example.org</a>>' port='6000'/> <reconnect delay='10'/> </source></div><div> </div><div>Another solution would be do add a totally new XML element. </div><div>What would be your preferred solution? </div><div> </div><div>Thanks again </div><div>Christian </div><div> </div><div> </div></div> <div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Fri, 27 Jan 2023 at 23:42, Jonathon Jongsma <<a href="mailto:jjongsma@redhat.com">jjongsma@redhat.com</a>> wrote: </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">On 1/27/23 8:40 AM, Christian Nautze wrote: > Hi! > > Is it possible to get a review on this patch I send before Christmas? :) > Thank you! > > Christian > > _____________________________________________________ > > Currently it's only possible to set this parameter during domain > creation via QEMU commandline passthrough feature. > With the new delay attribute it's also possible to set this > parameter if you want to attach a new NBD disk > using "virsh attach-device domain device.xml" e.g.: > > <disk type='network' device='disk'> > <driver name='qemu' type='raw'/> > <source protocol='nbd' name='foo'> > <host name='<a href="http://example.org" rel="noreferrer" target="_blank">example.org</a> <<a href="http://example.org" rel="noreferrer" target="_blank">http://example.org</a>>' port='6000'/> > <reconnect enabled='yes' delay='10'/> In my opinion, this doesn't seem like the ideal syntax for specifying this parameter. For example, it allows you to specify something like <reconnect enabled='no' ... /> which looks like it would disable any attempt by qemu to reconnect to the nbd export. But in your code, this just results in not passing any value for 'reconnect-delay' to qemu. And I'm pretty sure qemu will still attempt to reconnect to the nbd server in this case, but you will lose all of the requests made between the disconnection and a successful reconnection. Jonathon > </source> > <target dev='vdb' bus='virtio'/> > </disk> > > Signed-off-by: Christian Nautze <christian.nautze at <a href="http://exoscale.ch" rel="noreferrer" target="_blank">exoscale.ch</a> <<a href="https://listman.redhat.com/mailman/listinfo/libvir-list" rel="noreferrer" target="_blank">https://listman.redhat.com/mailman/listinfo/libvir-list</a>>> > --- > docs/formatdomain.rst | 10 ++++++-- > src/conf/domain_conf.c | 19 +++++++++++++++ > src/conf/schemas/domaincommon.rng | 3 +++ > src/conf/schemas/storagecommon.rng | 5 ++++ > src/conf/storage_source_conf.c | 1 + > src/conf/storage_source_conf.h | 4 ++++ > src/qemu/qemu_block.c | 4 +++- > src/qemu/qemu_domain.c | 9 ++++++++ > .../disk-network-nbd.x86_64-latest.args | 23 +++++++++++-------- > tests/qemuxml2argvdata/disk-network-nbd.xml | 8 +++++++ > tests/qemuxml2xmloutdata/disk-network-nbd.xml | 9 ++++++++ > 11 files changed, 82 insertions(+), 13 deletions(-) > > diff --git a/docs/formatdomain.rst b/docs/formatdomain.rst > index d7fffc6e0b..3fbeba644a 100644 > --- a/docs/formatdomain.rst > +++ b/docs/formatdomain.rst > @@ -2938,13 +2938,19 @@ paravirtualized driver is specified via the ``disk`` element. > are intended to be default, then the entire element may be omitted. > ``reconnect`` > For disk type ``vhostuser`` configures reconnect timeout if the connection > - is lost. It has two mandatory attributes: > + is lost. This is set with the two mandatory attributes ``enabled`` and > + ``timeout``. For disk type ``network`` and protocol ``nbd`` the QEMU NBD > + reconnect delay can be set via the mandatory attributes ``enabled`` > + and ``delay``: > > ``enabled`` > If the reconnect feature is enabled, accepts ``yes`` and ``no`` > ``timeout`` > The amount of seconds after which hypervisor tries to reconnect. > - > + ``delay`` > + The amount of seconds during which all requests are paused and will be rerun > + after a successful reconnect. After that time, any delayed requests and all > + future requests before a successful reconnect will immediately fail. > > For a "file" or "volume" disk type which represents a cdrom or floppy (the > ``device`` attribute), it is possible to define policy what to do with the > diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c > index 6c088ff295..909c78ef28 100644 > --- a/src/conf/domain_conf.c > +++ b/src/conf/domain_conf.c > @@ -7024,6 +7024,22 @@ virDomainDiskSourceNetworkParse(xmlNodePtr node, > src->tlsFromConfig = !!value; > } > > + if (src->protocol == VIR_STORAGE_NET_PROTOCOL_NBD) { > + xmlNodePtr cur; > + if ((cur = virXPathNode("./reconnect", ctxt))) { > + virTristateBool enabled; > + if (virXMLPropTristateBool(cur, "enabled", VIR_XML_PROP_NONE, > + &enabled) < 0) > + return -1; > + > + if (enabled == VIR_TRISTATE_BOOL_YES) { > + if (virXMLPropUInt(cur, "delay", 10, VIR_XML_PROP_REQUIRED, > + &src->reconnectDelay) < 0) > + return -1; > + } > + } > + } > + > /* for historical reasons we store the volume and image name in one XML > * element although it complicates thing when attempting to access them. */ > if (src->path && > @@ -21729,6 +21745,9 @@ virDomainDiskSourceFormatNetwork(virBuffer *attrBuf, > virBufferAddLit(childBuf, "/>\n"); > } > > + if (src->reconnectDelay) { > + virBufferAsprintf(childBuf, "<reconnect enabled='yes' delay='%u'/>\n", src->reconnectDelay); > + } > > virBufferEscapeString(childBuf, "<snapshot name='%s'/>\n", src->snapshot); > virBufferEscapeString(childBuf, "<config file='%s'/>\n", src->configFile); > diff --git a/src/conf/schemas/domaincommon.rng b/src/conf/schemas/domaincommon.rng > index c588a48fd2..72587416fe 100644 > --- a/src/conf/schemas/domaincommon.rng > +++ b/src/conf/schemas/domaincommon.rng > @@ -2184,6 +2184,9 @@ > </optional> > <ref name="diskSourceCommon"/> > <ref name="diskSourceNetworkHost"/> > + <optional> > + <ref name="reconnect"/> > + </optional> > <optional> > <ref name="encryption"/> > </optional> > diff --git a/src/conf/schemas/storagecommon.rng b/src/conf/schemas/storagecommon.rng > index 76714c9aad..2842376e78 100644 > --- a/src/conf/schemas/storagecommon.rng > +++ b/src/conf/schemas/storagecommon.rng > @@ -61,6 +61,11 @@ > <ref name="unsignedInt"/> > </attribute> > </optional> > + <optional> > + <attribute name="delay"> > + <ref name="unsignedInt"/> > + </attribute> > + </optional> > </element> > </define> > > diff --git a/src/conf/storage_source_conf.c b/src/conf/storage_source_conf.c > index 2b4cf5e241..edfd17c77c 100644 > --- a/src/conf/storage_source_conf.c > +++ b/src/conf/storage_source_conf.c > @@ -810,6 +810,7 @@ virStorageSourceCopy(const virStorageSource *src, > def->sslverify = src->sslverify; > def->readahead = src->readahead; > def->timeout = src->timeout; > + def->reconnectDelay = src->reconnectDelay; > def->metadataCacheMaxSize = src->metadataCacheMaxSize; > > /* storage driver metadata are not copied */ > diff --git a/src/conf/storage_source_conf.h b/src/conf/storage_source_conf.h > index f2440cec6a..b60a4b3346 100644 > --- a/src/conf/storage_source_conf.h > +++ b/src/conf/storage_source_conf.h > @@ -290,6 +290,10 @@ struct _virStorageSource { > unsigned long long readahead; /* size of the readahead buffer in bytes */ > unsigned long long timeout; /* connection timeout in seconds */ > > + /* NBD QEMU reconnect-delay option, > + * 0 as default value */ > + unsigned int reconnectDelay; > + > virStorageSourceNVMeDef *nvme; /* type == VIR_STORAGE_TYPE_NVME */ > > virDomainChrSourceDef *vhostuser; /* type == VIR_STORAGE_TYPE_VHOST_USER */ > diff --git a/src/qemu/qemu_block.c b/src/qemu/qemu_block.c > index 8a6f601b29..6913c380a0 100644 > --- a/src/qemu/qemu_block.c > +++ b/src/qemu/qemu_block.c > @@ -530,6 +530,7 @@ qemuBlockStorageSourceGetNBDProps(virStorageSource *src, > "S:export", src->path, > "S:tls-creds", tlsAlias, > "S:tls-hostname", tlsHostname, > + "p:reconnect-delay", src->reconnectDelay, > NULL) < 0) > return NULL; > > @@ -1817,7 +1818,8 @@ qemuBlockGetBackingStoreString(virStorageSource *src, > src->ncookies == 0 && > src->sslverify == VIR_TRISTATE_BOOL_ABSENT && > src->timeout == 0 && > - src->readahead == 0) { > + src->readahead == 0 && > + src->reconnectDelay == 0) { > > switch ((virStorageNetProtocol) src->protocol) { > case VIR_STORAGE_NET_PROTOCOL_NBD: > diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c > index 5c05032ce3..840d857f78 100644 > --- a/src/qemu/qemu_domain.c > +++ b/src/qemu/qemu_domain.c > @@ -4927,6 +4927,15 @@ qemuDomainValidateStorageSource(virStorageSource *src, > } > } > > + if (src->reconnectDelay > 0) { > + if (actualType != VIR_STORAGE_TYPE_NETWORK || > + src->protocol != VIR_STORAGE_NET_PROTOCOL_NBD) { > + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s", > + _("reconnect delay is supported only with NBD protocol")); > + return -1; > + } > + } > + > if (src->query && > (actualType != VIR_STORAGE_TYPE_NETWORK || > (src->protocol != VIR_STORAGE_NET_PROTOCOL_HTTPS && > diff --git a/tests/qemuxml2argvdata/disk-network-nbd.x86_64-latest.args b/tests/qemuxml2argvdata/disk-network-nbd.x86_64-latest.args > index 21e619af3e..e8d13b0bd4 100644 > --- a/tests/qemuxml2argvdata/disk-network-nbd.x86_64-latest.args > +++ b/tests/qemuxml2argvdata/disk-network-nbd.x86_64-latest.args > @@ -28,21 +28,24 @@ XDG_CONFIG_HOME=/tmp/lib/domain--1-QEMUGuest1/.config \ > -no-acpi \ > -boot strict=on \ > -device '{"driver":"piix3-usb-uhci","id":"usb","bus":"pci.0","addr":"0x1.0x2"}' \ > --blockdev '{"driver":"nbd","server":{"type":"inet","host":"<a href="http://example.org" rel="noreferrer" target="_blank">example.org</a> <<a href="http://example.org" rel="noreferrer" target="_blank">http://example.org</a>>","port":"6000"},"node-name":"libvirt-5-storage","auto-read-only":true,"discard":"unmap"}' \ > +-blockdev '{"driver":"nbd","server":{"type":"inet","host":"<a href="http://example.org" rel="noreferrer" target="_blank">example.org</a> <<a href="http://example.org" rel="noreferrer" target="_blank">http://example.org</a>>","port":"6000"},"node-name":"libvirt-6-storage","auto-read-only":true,"discard":"unmap"}' \ > +-blockdev '{"node-name":"libvirt-6-format","read-only":false,"driver":"raw","file":"libvirt-6-storage"}' \ > +-device '{"driver":"virtio-blk-pci","bus":"pci.0","addr":"0x2","drive":"libvirt-6-format","id":"virtio-disk0","bootindex":1}' \ > +-blockdev '{"driver":"nbd","server":{"type":"inet","host":"<a href="http://example.org" rel="noreferrer" target="_blank">example.org</a> <<a href="http://example.org" rel="noreferrer" target="_blank">http://example.org</a>>","port":"6000"},"export":"bar","node-name":"libvirt-5-storage","auto-read-only":true,"discard":"unmap"}' \ > -blockdev '{"node-name":"libvirt-5-format","read-only":false,"driver":"raw","file":"libvirt-5-storage"}' \ > --device '{"driver":"virtio-blk-pci","bus":"pci.0","addr":"0x2","drive":"libvirt-5-format","id":"virtio-disk0","bootindex":1}' \ > --blockdev '{"driver":"nbd","server":{"type":"inet","host":"<a href="http://example.org" rel="noreferrer" target="_blank">example.org</a> <<a href="http://example.org" rel="noreferrer" target="_blank">http://example.org</a>>","port":"6000"},"export":"bar","node-name":"libvirt-4-storage","auto-read-only":true,"discard":"unmap"}' \ > +-device '{"driver":"virtio-blk-pci","bus":"pci.0","addr":"0x3","drive":"libvirt-5-format","id":"virtio-disk1"}' \ > +-blockdev '{"driver":"nbd","server":{"type":"inet","host":"::1","port":"6000"},"node-name":"libvirt-4-storage","auto-read-only":true,"discard":"unmap"}' \ > -blockdev '{"node-name":"libvirt-4-format","read-only":false,"driver":"raw","file":"libvirt-4-storage"}' \ > --device '{"driver":"virtio-blk-pci","bus":"pci.0","addr":"0x3","drive":"libvirt-4-format","id":"virtio-disk1"}' \ > --blockdev '{"driver":"nbd","server":{"type":"inet","host":"::1","port":"6000"},"node-name":"libvirt-3-storage","auto-read-only":true,"discard":"unmap"}' \ > +-device '{"driver":"virtio-blk-pci","bus":"pci.0","addr":"0x4","drive":"libvirt-4-format","id":"virtio-disk2"}' \ > +-blockdev '{"driver":"nbd","server":{"type":"inet","host":"::1","port":"6000"},"export":"bar","node-name":"libvirt-3-storage","auto-read-only":true,"discard":"unmap"}' \ > -blockdev '{"node-name":"libvirt-3-format","read-only":false,"driver":"raw","file":"libvirt-3-storage"}' \ > --device '{"driver":"virtio-blk-pci","bus":"pci.0","addr":"0x4","drive":"libvirt-3-format","id":"virtio-disk2"}' \ > --blockdev '{"driver":"nbd","server":{"type":"inet","host":"::1","port":"6000"},"export":"bar","node-name":"libvirt-2-storage","auto-read-only":true,"discard":"unmap"}' \ > +-device '{"driver":"virtio-blk-pci","bus":"pci.0","addr":"0x5","drive":"libvirt-3-format","id":"virtio-disk3"}' \ > +-blockdev '{"driver":"nbd","server":{"type":"unix","path":"/var/run/nbdsock"},"export":"bar","node-name":"libvirt-2-storage","auto-read-only":true,"discard":"unmap"}' \ > -blockdev '{"node-name":"libvirt-2-format","read-only":false,"driver":"raw","file":"libvirt-2-storage"}' \ > --device '{"driver":"virtio-blk-pci","bus":"pci.0","addr":"0x5","drive":"libvirt-2-format","id":"virtio-disk3"}' \ > --blockdev '{"driver":"nbd","server":{"type":"unix","path":"/var/run/nbdsock"},"export":"bar","node-name":"libvirt-1-storage","auto-read-only":true,"discard":"unmap"}' \ > +-device '{"driver":"virtio-blk-pci","bus":"pci.0","addr":"0x6","drive":"libvirt-2-format","id":"virtio-disk4"}' \ > +-blockdev '{"driver":"nbd","server":{"type":"inet","host":"<a href="http://example.org" rel="noreferrer" target="_blank">example.org</a> <<a href="http://example.org" rel="noreferrer" target="_blank">http://example.org</a>>","port":"6000"},"export":"foo","reconnect-delay":10,"node-name":"libvirt-1-storage","auto-read-only":true,"discard":"unmap"}' \ > -blockdev '{"node-name":"libvirt-1-format","read-only":false,"driver":"raw","file":"libvirt-1-storage"}' \ > --device '{"driver":"virtio-blk-pci","bus":"pci.0","addr":"0x6","drive":"libvirt-1-format","id":"virtio-disk4"}' \ > +-device '{"driver":"virtio-blk-pci","bus":"pci.0","addr":"0x7","drive":"libvirt-1-format","id":"virtio-disk5"}' \ > -audiodev '{"id":"audio1","driver":"none"}' \ > -sandbox on,obsolete=deny,elevateprivileges=deny,spawn=deny,resourcecontrol=deny \ > -msg timestamp=on > diff --git a/tests/qemuxml2argvdata/disk-network-nbd.xml b/tests/qemuxml2argvdata/disk-network-nbd.xml > index 8ac6cc3b7b..243ffeb1ed 100644 > --- a/tests/qemuxml2argvdata/disk-network-nbd.xml > +++ b/tests/qemuxml2argvdata/disk-network-nbd.xml > @@ -49,6 +49,14 @@ > </source> > <target dev='vde' bus='virtio'/> > </disk> > + <disk type='network' device='disk'> > + <driver name='qemu' type='raw'/> > + <source protocol='nbd' name='foo'> > + <host name='<a href="http://example.org" rel="noreferrer" target="_blank">example.org</a> <<a href="http://example.org" rel="noreferrer" target="_blank">http://example.org</a>>' port='6000'/> > + <reconnect enabled='yes' delay='10'/> > + </source> > + <target dev='vdf' bus='virtio'/> > + </disk> > <controller type='usb' index='0'/> > <controller type='ide' index='0'/> > <controller type='pci' index='0' model='pci-root'/> > diff --git a/tests/qemuxml2xmloutdata/disk-network-nbd.xml b/tests/qemuxml2xmloutdata/disk-network-nbd.xml > index f8dcca4bab..ed0c760d5b 100644 > --- a/tests/qemuxml2xmloutdata/disk-network-nbd.xml > +++ b/tests/qemuxml2xmloutdata/disk-network-nbd.xml > @@ -54,6 +54,15 @@ > <target dev='vde' bus='virtio'/> > <address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0'/> > </disk> > + <disk type='network' device='disk'> > + <driver name='qemu' type='raw'/> > + <source protocol='nbd' name='foo'> > + <host name='<a href="http://example.org" rel="noreferrer" target="_blank">example.org</a> <<a href="http://example.org" rel="noreferrer" target="_blank">http://example.org</a>>' port='6000'/> > + <reconnect enabled='yes' delay='10'/> > + </source> > + <target dev='vdf' bus='virtio'/> > + <address type='pci' domain='0x0000' bus='0x00' slot='0x07' function='0x0'/> > + </disk> > <controller type='usb' index='0'> > <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x2'/> > </controller> > -- > 2.34.1 > </blockquote></div>