Prepare for new checkpoint APIs by describing the XML that will represent a checkpoint. The checkpoint XML is modeled heavily after virDomainSnapshotPtr. (See the docs for more details). Add testsuite coverage for some minimal uses of the XML (bare minimum, the sample from html, and a full dumpxml). Although use of the REDEFINE flag will require the <domain> subelement to be present, it is easier for most of the tests to provide counterpart output produced with the NO_DOMAIN flag (particularly since synthesizing a valid <domain> during testing is not trivial). Signed-off-by: Eric Blake <eblake@xxxxxxxxxx> Reviewed-by: Daniel P. Berrangé <berrange@xxxxxxxxxx> --- docs/docs.html.in | 3 +- docs/format.html.in | 1 + docs/formatcheckpoint.html.in | 202 +++++++++++++++++++ docs/index.html.in | 3 +- docs/schemas/domaincheckpoint.rng | 87 ++++++++ libvirt.spec.in | 1 + mingw-libvirt.spec.in | 2 + tests/Makefile.am | 2 + tests/domaincheckpointxml2xmlin/empty.xml | 1 + tests/domaincheckpointxml2xmlin/redefine.xml | 63 ++++++ tests/domaincheckpointxml2xmlin/sample.xml | 7 + tests/domaincheckpointxml2xmlin/size.xml | 4 + tests/domaincheckpointxml2xmlout/empty.xml | 7 + tests/domaincheckpointxml2xmlout/sample.xml | 12 ++ tests/domaincheckpointxml2xmlout/size.xml | 11 + tests/virschematest.c | 2 + 16 files changed, 406 insertions(+), 2 deletions(-) create mode 100644 docs/formatcheckpoint.html.in create mode 100644 docs/schemas/domaincheckpoint.rng create mode 100644 tests/domaincheckpointxml2xmlin/empty.xml create mode 100644 tests/domaincheckpointxml2xmlin/redefine.xml create mode 100644 tests/domaincheckpointxml2xmlin/sample.xml create mode 100644 tests/domaincheckpointxml2xmlin/size.xml create mode 100644 tests/domaincheckpointxml2xmlout/empty.xml create mode 100644 tests/domaincheckpointxml2xmlout/sample.xml create mode 100644 tests/domaincheckpointxml2xmlout/size.xml diff --git a/docs/docs.html.in b/docs/docs.html.in index d0ff844d0c..f6e599b77b 100644 --- a/docs/docs.html.in +++ b/docs/docs.html.in @@ -80,7 +80,8 @@ <a href="formatstoragecaps.html">storage pool capabilities</a>, <a href="formatnode.html">node devices</a>, <a href="formatsecret.html">secrets</a>, - <a href="formatsnapshot.html">snapshots</a></dd> + <a href="formatsnapshot.html">snapshots</a>, + <a href="formatcheckpoint.html">checkpoints</a></dd> <dt><a href="uri.html">URI format</a></dt> <dd>The URI formats used for connecting to libvirt</dd> diff --git a/docs/format.html.in b/docs/format.html.in index 640a9957ee..20f9ef3348 100644 --- a/docs/format.html.in +++ b/docs/format.html.in @@ -25,6 +25,7 @@ <li><a href="formatnode.html">Node devices</a></li> <li><a href="formatsecret.html">Secrets</a></li> <li><a href="formatsnapshot.html">Snapshots</a></li> + <li><a href="formatcheckpoint.html">Checkpoints</a></li> </ul> <h2>Command line validation</h2> diff --git a/docs/formatcheckpoint.html.in b/docs/formatcheckpoint.html.in new file mode 100644 index 0000000000..5c844f1f27 --- /dev/null +++ b/docs/formatcheckpoint.html.in @@ -0,0 +1,202 @@ +<?xml version="1.0" encoding="UTF-8"?> +<!DOCTYPE html> +<html xmlns="http://www.w3.org/1999/xhtml"> + <body> + <h1>Checkpoint XML format</h1> + + <ul id="toc"></ul> + + <h2><a id="CheckpointAttributes">Checkpoint XML</a></h2> + + <p> + One method of capturing domain disk backups is via the use of + incremental backups. Right now, incremental backups are only + supported for the QEMU hypervisor when using qcow2 disks at the + active layer; if other disk formats are in use, capturing disk + backups requires different libvirt APIs. + </p> + <p> + Libvirt is able to facilitate incremental backups by tracking + disk checkpoints, which are points in time against which it is + easy to compute which portion of the disk has changed. Given a + full backup (a backup created from the creation of the disk to a + given point in time), coupled with the creation of a disk + checkpoint at that time, and an incremental backup (a backup + created from just the dirty portion of the disk between the + first checkpoint and the second backup operation), it is + possible to do an offline reconstruction of the state of the + disk at the time of the second backup without having to copy as + much data as a second full backup would require. Most disk + checkpoints are created in conjunction with a backup + via <code>virDomainBackupBegin()</code> or with a snapshot + via <code>virDomainSnapshotCreateXML2</code>; however, libvirt + also exposes enough support to create disk checkpoints + independently from a backup operation + via <code>virDomainCheckpointCreateXML()</code>. + </p> + <p> + Attributes of libvirt checkpoints are stored as child elements + of the <code>domaincheckpoint</code> element. At checkpoint + creation time, normally only + the <code>name</code>, <code>description</code>, + and <code>disks</code> elements are settable. The rest of the + fields are ignored on creation and will be filled in by libvirt + in for informational purposes + by <code>virDomainCheckpointGetXMLDesc()</code>. However, when + redefining a checkpoint, with + the <code>VIR_DOMAIN_CHECKPOINT_CREATE_REDEFINE</code> flag + of <code>virDomainCheckpointCreateXML()</code>, all of the XML + fields described here are relevant on input, even the fields + that are normally described as readonly for output. + </p> + <p> + Checkpoints are maintained in a hierarchy. A domain can have a + current checkpoint, which is the most recent checkpoint compared + to the current state of the domain (although a domain might have + checkpoints without a current checkpoint, if checkpoints have + been deleted in the meantime). Creating a checkpoint sets that + checkpoint as current and the prior current checkpoint is the + parent of the new checkpoint. In the future, reverting to a + domain snapshot may also affect the current checkpoint. + </p> + <p> + The top-level <code>domaincheckpoint</code> element may contain + the following elements: + </p> + <dl> + <dt><code>name</code></dt> + <dd>The optional name for this checkpoint. If the name is + omitted, libvirt will create a name based on the time of the + creation. + </dd> + <dt><code>description</code></dt> + <dd>An optional human-readable description of the checkpoint. + If the description is omitted when initially creating the + checkpoint, then this field will be empty. + </dd> + <dt><code>disks</code></dt> + <dd>On input, this is an optional listing of specific + instructions for disk checkpoints; it is needed when making a + checkpoint on only a subset of the disks associated with a + domain. In particular, since QEMU checkpoints require qcow2 + disks, this element may be needed on input for excluding guest + disks that are not in qcow2 format. If the entire element was + omitted on input, then all disks participate in the + checkpoint, otherwise, only the disks explicitly listed which + do not also use <code>checkpoint='no'</code> will + participate. On output, this is the checkpoint state of each + of the domain's disks. + <dl> + <dt><code>disk</code></dt> + <dd>This sub-element describes the checkpoint properties of + a specific disk with the following attributes: + <dl> + <dt><code>name</code></dt> + <dd>A mandatory attribute which must match either + the <code><target dev='name'/></code> or an + unambiguous <code><source file='name'/></code> + of one of + the <a href="formatdomain.html#elementsDisks">disk + devices</a> specified for the domain at the time of + the checkpoint.</dd> + <dt><code>checkpoint</code></dt> + <dd>An optional attribute; possible values + are <code>no</code> when the disk does not participate + in this checkpoint; or <code>bitmap</code> if the disk + will track all changes since the creation of this + checkpoint via a bitmap.</dd> + <dt><code>bitmap</code></dt> + <dd>The attribute <code>bitmap</code> is only valid + if <code>checkpoint='bitmap'</code>; it describes the + name of the tracking bitmap (defaulting to the + checkpoint name).</dd> + <dt><code>size</code></dt> + <dd>The attribute <code>size</code> is ignored on input; + on output, it is only present if + the <code>VIR_DOMAIN_CHECKPOINT_XML_SIZE</code> flag + was used to perform a dynamic query of the estimated + size in bytes of the changes made since the checkpoint + was created.</dd> + </dl> + </dd> + </dl> + </dd> + <dt><code>creationTime</code></dt> + <dd>A readonly representation of the time this checkpoint was + created. The time is specified in seconds since the Epoch, + UTC (i.e. Unix time). + </dd> + <dt><code>parent</code></dt> + <dd>An optional readonly representation of the parent of this + checkpoint. If present, this element contains exactly one + child element, <code>name</code>. + </dd> + <dt><code>domain</code></dt> + <dd>A readonly representation of the + inactive <a href="formatdomain.html">domain configuration</a> + at the time the checkpoint was created. This element may be + omitted for output brevity by supplying + the <code>VIR_DOMAIN_CHECKPOINT_XML_NO_DOMAIN</code> flag, but + the resulting XML is no longer viable for use with + the <code>VIR_DOMAIN_CHECKPOINT_CREATE_REDEFINE</code> flag + of <code>virDomainCheckpointCreateXML()</code>. The domain + will have security-sensitive information omitted unless the + flag <code>VIR_DOMAIN_SNAPSHOT_XML_SECURE</code> is provided + on a read-write connection. + </dd> + </dl> + + <h2><a id="example">Examples</a></h2> + + <p>Using this XML to create a checkpoint of just vda on a qemu + domain with two disks and a prior checkpoint:</p> + <pre> +<domaincheckpoint> + <description>Completion of updates after OS install</description> + <disks> + <disk name='vda' checkpoint='bitmap'/> + <disk name='vdb' checkpoint='no'/> + </disks> +</domaincheckpoint></pre> + + <p>will result in XML similar to this from + <code>virDomainCheckpointGetXMLDesc()</code>:</p> + <pre> +<domaincheckpoint> + <name>1525889631</name> + <description>Completion of updates after OS install</description> + <creationTime>1525889631</creationTime> + <parent> + <name>1525111885</name> + </parent> + <disks> + <disk name='vda' checkpoint='bitmap' bitmap='1525889631'/> + <disk name='vdb' checkpoint='no'/> + </disks> + <domain type='qemu'> + <name>fedora</name> + <uuid>93a5c045-6457-2c09-e56c-927cdf34e178</uuid> + <memory>1048576</memory> + ... + <devices> + <disk type='file' device='disk'> + <driver name='qemu' type='qcow2'/> + <source file='/path/to/file1'/> + <target dev='vda' bus='virtio'/> + </disk> + <disk type='file' device='disk' snapshot='external'> + <driver name='qemu' type='raw'/> + <source file='/path/to/file2'/> + <target dev='vdb' bus='virtio'/> + </disk> + ... + </devices> + </domain> +</domaincheckpoint></pre> + + <p>With that checkpoint created, the qcow2 image is now tracking + all changes that occur in the image since the checkpoint via + the persistent bitmap named <code>1525889631</code>. + </p> + </body> +</html> diff --git a/docs/index.html.in b/docs/index.html.in index f593445d06..0315915402 100644 --- a/docs/index.html.in +++ b/docs/index.html.in @@ -69,7 +69,8 @@ <a href="formatstoragecaps.html">storage pool capabilities</a>, <a href="formatnode.html">node devices</a>, <a href="formatsecret.html">secrets</a>, - <a href="formatsnapshot.html">snapshots</a></dd> + <a href="formatsnapshot.html">snapshots</a>, + <a href="formatcheckpoint.html">checkpoints</a></dd> <dt><a href="http://wiki.libvirt.org">Wiki</a></dt> <dd>Read further community contributed content</dd> </dl> diff --git a/docs/schemas/domaincheckpoint.rng b/docs/schemas/domaincheckpoint.rng new file mode 100644 index 0000000000..46d3ec1259 --- /dev/null +++ b/docs/schemas/domaincheckpoint.rng @@ -0,0 +1,87 @@ +<?xml version="1.0"?> +<!-- A Relax NG schema for the libvirt domain checkpoint properties XML format --> +<grammar xmlns="http://relaxng.org/ns/structure/1.0"> + <start> + <ref name='domaincheckpoint'/> + </start> + + <include href='domaincommon.rng'/> + + <define name='domaincheckpoint'> + <element name='domaincheckpoint'> + <interleave> + <optional> + <element name='name'> + <text/> + </element> + </optional> + <optional> + <element name='description'> + <text/> + </element> + </optional> + <optional> + <element name='creationTime'> + <text/> + </element> + </optional> + <optional> + <element name='disks'> + <oneOrMore> + <ref name='diskcheckpoint'/> + </oneOrMore> + </element> + </optional> + <optional> + <!-- Nested grammar ensures that any of our overrides of + storagecommon/domaincommon defines do not conflict + with any domain.rng overrides. --> + <grammar> + <include href='domain.rng'/> + </grammar> + </optional> + <optional> + <element name='parent'> + <element name='name'> + <text/> + </element> + </element> + </optional> + </interleave> + </element> + </define> + + <define name='diskcheckpoint'> + <element name='disk'> + <attribute name='name'> + <choice> + <ref name='diskTarget'/> + <ref name='absFilePath'/> + </choice> + </attribute> + <choice> + <attribute name='checkpoint'> + <value>no</value> + </attribute> + <group> + <optional> + <attribute name='checkpoint'> + <value>bitmap</value> + </attribute> + </optional> + <optional> + <attribute name='bitmap'> + <text/> + </attribute> + </optional> + <optional> + <attribute name='size'> + <ref name="unsignedLong"/> + </attribute> + </optional> + </group> + </choice> + </element> + </define> + +</grammar> diff --git a/libvirt.spec.in b/libvirt.spec.in index b7a35a0fb1..6a730befdd 100644 --- a/libvirt.spec.in +++ b/libvirt.spec.in @@ -1800,6 +1800,7 @@ exit 0 %{_datadir}/libvirt/schemas/cputypes.rng %{_datadir}/libvirt/schemas/domain.rng %{_datadir}/libvirt/schemas/domaincaps.rng +%{_datadir}/libvirt/schemas/domaincheckpoint.rng %{_datadir}/libvirt/schemas/domaincommon.rng %{_datadir}/libvirt/schemas/domainsnapshot.rng %{_datadir}/libvirt/schemas/interface.rng diff --git a/mingw-libvirt.spec.in b/mingw-libvirt.spec.in index bea822fd73..553533c88f 100644 --- a/mingw-libvirt.spec.in +++ b/mingw-libvirt.spec.in @@ -240,6 +240,7 @@ rm -rf $RPM_BUILD_ROOT%{mingw64_libexecdir}/libvirt-guests.sh %{mingw32_datadir}/libvirt/schemas/cputypes.rng %{mingw32_datadir}/libvirt/schemas/domain.rng %{mingw32_datadir}/libvirt/schemas/domaincaps.rng +%{mingw32_datadir}/libvirt/schemas/domaincheckpoint.rng %{mingw32_datadir}/libvirt/schemas/domaincommon.rng %{mingw32_datadir}/libvirt/schemas/domainsnapshot.rng %{mingw32_datadir}/libvirt/schemas/interface.rng @@ -328,6 +329,7 @@ rm -rf $RPM_BUILD_ROOT%{mingw64_libexecdir}/libvirt-guests.sh %{mingw64_datadir}/libvirt/schemas/cputypes.rng %{mingw64_datadir}/libvirt/schemas/domain.rng %{mingw64_datadir}/libvirt/schemas/domaincaps.rng +%{mingw64_datadir}/libvirt/schemas/domaincheckpoint.rng %{mingw64_datadir}/libvirt/schemas/domaincommon.rng %{mingw64_datadir}/libvirt/schemas/domainsnapshot.rng %{mingw64_datadir}/libvirt/schemas/interface.rng diff --git a/tests/Makefile.am b/tests/Makefile.am index d3cdbff8bb..c552d08e12 100644 --- a/tests/Makefile.am +++ b/tests/Makefile.am @@ -83,6 +83,8 @@ EXTRA_DIST = \ commanddata \ cputestdata \ domaincapsschemadata \ + domaincheckpointxml2xmlin \ + domaincheckpointxml2xmlout \ domainconfdata \ domainschemadata \ domainsnapshotxml2xmlin \ diff --git a/tests/domaincheckpointxml2xmlin/empty.xml b/tests/domaincheckpointxml2xmlin/empty.xml new file mode 100644 index 0000000000..dc36449142 --- /dev/null +++ b/tests/domaincheckpointxml2xmlin/empty.xml @@ -0,0 +1 @@ +<domaincheckpoint/> diff --git a/tests/domaincheckpointxml2xmlin/redefine.xml b/tests/domaincheckpointxml2xmlin/redefine.xml new file mode 100644 index 0000000000..823ae1ee2d --- /dev/null +++ b/tests/domaincheckpointxml2xmlin/redefine.xml @@ -0,0 +1,63 @@ +<domaincheckpoint> + <name>c1</name> + <creationTime>1553647812</creationTime> + <disks> + <disk name='hda' checkpoint='no'/> + <disk name='hdc' checkpoint='no'/> + <disk name='vda' checkpoint='bitmap' bitmap='c1'/> + <disk name='vdb' checkpoint='bitmap' bitmap='c1'/> + </disks> + <domain type='qemu'> + <name>QEMUGuest1</name> + <uuid>c7a5fdbd-edaf-9455-926a-d65c16db1809</uuid> + <memory unit='KiB'>219136</memory> + <currentMemory unit='KiB'>219136</currentMemory> + <vcpu placement='static'>1</vcpu> + <os> + <type arch='i686' machine='pc'>hvm</type> + <boot dev='hd'/> + </os> + <clock offset='utc'/> + <on_poweroff>destroy</on_poweroff> + <on_reboot>restart</on_reboot> + <on_crash>destroy</on_crash> + <devices> + <emulator>/usr/bin/qemu-system-i686</emulator> + <disk type='block' device='disk'> + <driver name='qemu' type='raw'/> + <source dev='/dev/HostVG/QEMUGuest1'/> + <target dev='hda' bus='ide'/> + <address type='drive' controller='0' bus='0' target='0' unit='0'/> + </disk> + <disk type='block' device='cdrom'> + <driver name='qemu' type='raw'/> + <source dev='/dev/HostVG/QEMUGuest2'/> + <target dev='hdc' bus='ide'/> + <readonly/> + <address type='drive' controller='0' bus='1' target='0' unit='0'/> + </disk> + <disk type='file' device='disk'> + <driver name='qemu' type='qcow2'/> + <source file='/tmp/data.img'/> + <target dev='vda' bus='virtio'/> + <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/> + </disk> + <disk type='file' device='disk'> + <driver name='qemu' type='qcow2'/> + <source file='/tmp/logs.img'/> + <target dev='vdb' bus='virtio'/> + <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/> + </disk> + <controller type='usb' index='0'> + <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x2'/> + </controller> + <controller type='ide' index='0'> + <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1'/> + </controller> + <controller type='pci' index='0' model='pci-root'/> + <input type='mouse' bus='ps2'/> + <input type='keyboard' bus='ps2'/> + <memballoon model='none'/> + </devices> + </domain> +</domaincheckpoint> diff --git a/tests/domaincheckpointxml2xmlin/sample.xml b/tests/domaincheckpointxml2xmlin/sample.xml new file mode 100644 index 0000000000..70ed964e1e --- /dev/null +++ b/tests/domaincheckpointxml2xmlin/sample.xml @@ -0,0 +1,7 @@ +<domaincheckpoint> + <description>Completion of updates after OS install</description> + <disks> + <disk name='vda' checkpoint='bitmap'/> + <disk name='vdb' checkpoint='no'/> + </disks> +</domaincheckpoint> diff --git a/tests/domaincheckpointxml2xmlin/size.xml b/tests/domaincheckpointxml2xmlin/size.xml new file mode 100644 index 0000000000..99ce84c7a0 --- /dev/null +++ b/tests/domaincheckpointxml2xmlin/size.xml @@ -0,0 +1,4 @@ +<domaincheckpoint> + <name>c2</name> + <description>something fun</description> +</domaincheckpoint> diff --git a/tests/domaincheckpointxml2xmlout/empty.xml b/tests/domaincheckpointxml2xmlout/empty.xml new file mode 100644 index 0000000000..6fe6124ce4 --- /dev/null +++ b/tests/domaincheckpointxml2xmlout/empty.xml @@ -0,0 +1,7 @@ +<domaincheckpoint> + <name>1525889631</name> + <creationTime>1525889631</creationTime> + <disks> + <disk name='vda' checkpoint='bitmap' bitmap='1525889631'/> + </disks> +</domaincheckpoint> diff --git a/tests/domaincheckpointxml2xmlout/sample.xml b/tests/domaincheckpointxml2xmlout/sample.xml new file mode 100644 index 0000000000..d219553435 --- /dev/null +++ b/tests/domaincheckpointxml2xmlout/sample.xml @@ -0,0 +1,12 @@ +<domaincheckpoint> + <name>1525889631</name> + <description>Completion of updates after OS install</description> + <creationTime>1525889631</creationTime> + <parent> + <name>1525111885</name> + </parent> + <disks> + <disk name='vda' checkpoint='bitmap' bitmap='1525889631'/> + <disk name='vdb' checkpoint='no'/> + </disks> +</domaincheckpoint> diff --git a/tests/domaincheckpointxml2xmlout/size.xml b/tests/domaincheckpointxml2xmlout/size.xml new file mode 100644 index 0000000000..8480e6522a --- /dev/null +++ b/tests/domaincheckpointxml2xmlout/size.xml @@ -0,0 +1,11 @@ +<domaincheckpoint> + <name>c2</name> + <description>something fun</description> + <parent> + <name>c1</name> + </parent> + <creationTime>1553648510</creationTime> + <disks> + <disk name='vda' checkpoint='bitmap' bitmap='1525889631' size='1048576'/> + </disks> +</domaincheckpoint> diff --git a/tests/virschematest.c b/tests/virschematest.c index 56bdcb2f88..fa99e67a57 100644 --- a/tests/virschematest.c +++ b/tests/virschematest.c @@ -222,6 +222,8 @@ mymain(void) "genericxml2xmloutdata", "xlconfigdata", "libxlxml2domconfigdata", "qemuhotplugtestdomains"); DO_TEST_DIR("domaincaps.rng", "domaincapsschemadata"); + DO_TEST_DIR("domaincheckpoint.rng", "domaincheckpointxml2xmlin", + "domaincheckpointxml2xmlout"); DO_TEST_DIR("domainsnapshot.rng", "domainsnapshotxml2xmlin", "domainsnapshotxml2xmlout"); DO_TEST_DIR("interface.rng", "interfaceschemadata"); -- 2.20.1 -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list