Re: [libvirt] [PATCH 3/7] conf: add features to volume target XML

Add <features> and <compat> elements to volume target XML. <compat> is a string which for qcow2 represents the QEMU version it should be compatible with. Valid values are 0.10 and 1.1. 1.1 is implicit if the <features> element is present, otherwise qemu-img default is used. 0.10 can be specified to explicitly create older images after the qemu-img default changes.

<features> contains optional features, so far <lazy_refcounts/> is available, which enables caching of reference counters, improving performance for snapshots. --- docs/formatstorage.html.in | 19 +++++++ docs/schemas/Makefile.am | 1 + docs/schemas/storagefilefeatures.rng | 24 +++++++++ docs/schemas/storagevol.rng | 7 +++ libvirt.spec.in | 1 + mingw-libvirt.spec.in | 2 + src/conf/storage_conf.c | 74 +++++++++++++++++++++++++++ src/conf/storage_conf.h | 7 ++- src/libvirt_private.syms | 2 + src/storage/storage_backend_fs.c | 10 ++++ tests/storagevolxml2xmlin/vol-qcow2-1.1.xml | 32 ++++++++++++ tests/storagevolxml2xmlin/vol-qcow2-lazy.xml | 35 +++++++++++++ tests/storagevolxml2xmlout/vol-qcow2-1.1.xml | 33 ++++++++++++ tests/storagevolxml2xmlout/vol-qcow2-lazy.xml | 35 +++++++++++++ tests/storagevolxml2xmltest.c | 2 + 15 files changed, 282 insertions(+), 2 deletions(-) create mode 100644 docs/schemas/storagefilefeatures.rng create mode 100644 tests/storagevolxml2xmlin/vol-qcow2-1.1.xml create mode 100644 tests/storagevolxml2xmlin/vol-qcow2-lazy.xml create mode 100644 tests/storagevolxml2xmlout/vol-qcow2-1.1.xml create mode 100644 tests/storagevolxml2xmlout/vol-qcow2-lazy.xml diff --git a/docs/formatstorage.html.in b/docs/formatstorage.html.in index 1a45915..30a07f4 100644 --- a/docs/formatstorage.html.in +++ b/docs/formatstorage.html.in @@ -334,6 +334,10 @@ &lt;mode&gt;0744&lt;/mode&gt; &lt;label&gt;virt_image_t&lt;/label&gt; &lt;/permissions&gt; + &lt;compat&gt;1.1&lt;/compat&gt; + &lt;features&gt; + &lt;lazy_refcounts/&gt; + &lt;/features&gt; &lt;/target&gt;</pre> <dl> @@ -362,6 +366,21 @@ contains the MAC (eg SELinux) label string. <span class="since">Since 0.4.1</span> </dd> + <dt><code>compat</code></dt> + <dd>Specify compatibility level. So far, this is only used for + <code>type='qcow2'</code> volumes. Valid values are <code>0.10</code> + and <code>1.1</code> so far, specifying QEMU version the images should + be compatible with. If the <code>feature</code> element is present, + 1.1 is used. If omitted, qemu-img default is used.

+ <span class="since">Since 1.0.6</span>

+ </dd> + <dt><code>features</code></dt> + <dd>Format-specific features. Only used for <code>qcow2</code> now. + Valid sub-elements are: + <code>&lt;lazy_refcounts/&gt;</code> - allow delayed reference + counter updates.

+ <span class="since">Since 1.0.6</span>

+ </dd> </dl> <h3><a name="StorageVolBacking">Backing store elements</a></h3> diff --git a/docs/schemas/Makefile.am b/docs/schemas/Makefile.am index 8da2c67..47d1941 100644 --- a/docs/schemas/Makefile.am +++ b/docs/schemas/Makefile.am @@ -28,6 +28,7 @@ schema_DATA = \ nwfilter.rng \ secret.rng \ storageencryption.rng \ + storagefilefeatures.rng \ storagepool.rng \ storagevol.rng diff --git a/docs/schemas/storagefilefeatures.rng b/docs/schemas/storagefilefeatures.rng new file mode 100644 index 0000000..96a1829 --- /dev/null +++ b/docs/schemas/storagefilefeatures.rng @@ -0,0 +1,24 @@ +<?xml version="1.0"?> +<!-- A Relax NG schema for the libvirt volume features XML format --> +<grammar xmlns="http://relaxng.org/ns/structure/1.0" + datatypeLibrary="http://www.w3.org/2001/XMLSchema-datatypes"> + + <define name='compat'> + <element name='compat'> + <data type='string'> + <param name='pattern'>[^,]+</param>

+ </data> + </element> + </define> + <define name='fileFormatFeatures'> + <element name='features'> + <interleave> + <optional> + <element name='lazy_refcounts'> + <empty/> + </element> + </optional> + </interleave> + </element> + </define> +</grammar>

diff --git a/src/conf/storage_conf.c b/src/conf/storage_conf.c index c58b728..35ad502 100644 --- a/src/conf/storage_conf.c +++ b/src/conf/storage_conf.c @@ -97,6 +97,8 @@ VIR_ENUM_IMPL(virStoragePoolSourceAdapterType, typedef const char *(*virStorageVolFormatToString)(int format); typedef int (*virStorageVolFormatFromString)(const char *format); +typedef const char *(*virStorageVolFeatureToString)(int feature); +typedef int (*virStorageVolFeatureFromString)(const char *feature); typedef const char *(*virStoragePoolFormatToString)(int format); typedef int (*virStoragePoolFormatFromString)(const char *format); @@ -107,6 +109,9 @@ struct _virStorageVolOptions { int defaultFormat; virStorageVolFormatToString formatToString; virStorageVolFormatFromString formatFromString; + virStorageVolFeatureToString featureToString; + virStorageVolFeatureFromString featureFromString; + int featureLast;

}; /* Flags to indicate mandatory components in the pool source */

@@ -1335,12 +1353,46 @@ virStorageVolDefParseXML(virStoragePoolDefPtr pool, VIR_FREE(format); } + ret->target.compat = virXPathString("string(./target/compat)", ctxt); + if (ret->target.compat && strchr(ret->target.compat, ',')) { + virReportError(VIR_ERR_XML_ERROR, "%s", + _("forbidden characters in 'compat' attribute"));

+ goto cleanup; + } + + if (virXPathNode("./target/features", ctxt) && options->featureLast) { + if ((n = virXPathNodeSet("./target/features/*", ctxt, &nodes)) < 0) + goto cleanup; + + if (!ret->target.compat && VIR_STRDUP(ret->target.compat, "1.1") < 0) + goto cleanup; + + if (!(ret->target.features = virBitmapNew(options->featureLast))) + goto no_memory; +

+ for (i = 0; i < n; i++) { + int f = options->featureFromString((const char*)nodes[i]->name); + + if (f < 0) { + virReportError(VIR_ERR_XML_ERROR, _("unsupported feature %s"), + (const char*)nodes[i]->name); + goto cleanup; + } + ignore_value(virBitmapSetBit(ret->target.features, f)); + } + VIR_FREE(nodes); + } +

if (virStorageDefParsePerms(ctxt, &ret->backingStore.perms, "./backingStore/permissions", DEFAULT_VOL_PERM_MODE) < 0) goto error; +no_memory: + virReportOOMError(); +

cleanup: + VIR_FREE(nodes); VIR_FREE(allocation); VIR_FREE(capacity); VIR_FREE(unit);