Re: [libvirt] [PATCH v3 1/2] conf: Add support of zero-detection for disks

This option allows or disallows detection of zero-writes if it is set to "on" or "off", respectively. It can be also set to "unmap" in which case it will try discarding that part of image based on the value of the "discard" option.

Signed-off-by: Martin Kletzander <mkletzan(a)redhat.com&gt; --- docs/formatdomain.html.in | 10 +++++ docs/schemas/domaincommon.rng | 12 ++++++ src/conf/domain_conf.c | 21 +++++++++- src/conf/domain_conf.h | 11 ++++++ src/libvirt_private.syms | 2 + .../qemuxml2argv-disk-drive-detect-zeroes.xml | 45 ++++++++++++++++++++++ .../qemuxml2xmlout-disk-drive-detect-zeroes.xml | 1 + tests/qemuxml2xmltest.c | 1 + 8 files changed, 101 insertions(+), 2 deletions(-) create mode 100644 tests/qemuxml2argvdata/qemuxml2argv-disk-drive-detect-zeroes.xml create mode 120000 tests/qemuxml2xmloutdata/qemuxml2xmlout-disk-drive-detect-zeroes.xml diff --git a/docs/formatdomain.html.in b/docs/formatdomain.html.in index d2db53b41823..3d09f511a8c4 100644 --- a/docs/formatdomain.html.in +++ b/docs/formatdomain.html.in @@ -2564,6 +2564,16 @@ are numbered from 1 to the domain iothreads value. <span class='since'>Since 1.2.8 (QEMU only)</span> </li> + <li> + The optional <code>detect_zeroes</code> attribute controls + whether to detect zero write requests. The value can be "off", + "on" or "unmap". First two values turn the detection off and + on, respectively, the third value turns the detection on and

+ tries to discard such areas from the image based on the value + of <code>discard</code> above (it will act as "on" if + <code>discard</code> is set to "ignore").

+ <span class='since'>Since 1.3.1 (QEMU and KVM only)</span>

+ </li> </ul> </dd> <dt><code>backenddomain</code></dt>

diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c index d8bed670f243..1a336d08cda5 100644 --- a/src/conf/domain_conf.c +++ b/src/conf/domain_conf.c

@@ -7062,7 +7068,7 @@ virDomainDiskDefDriverParseXML(virDomainDiskDefPtr def, } else { if ((def->src->format = virStorageFileFormatTypeFromString(tmp)) <= 0) { virReportError(VIR_ERR_CONFIG_UNSUPPORTED, - _("unknown driver format value '%s'"), tmp); + _("unknown driver type value '%s'"), tmp);

goto cleanup; } }