2:06 a.m.
https://bugzilla.redhat.com/show_bug.cgi?id=1434451
It comes handy for management application to be able to have a
per-device label so that it can uniquely identify devices it
cares about. The advantage of this approach is that we don't have
to generate aliases at define time (non trivial amount of work
and problems). The only thing we do is parse the user supplied
tag and format it back. For instance:
<disk type='block' device='disk'>
<driver name='qemu' type='raw'/>
<source dev='/dev/HostVG/QEMUGuest1'/>
<target dev='hda' bus='ide'/>
<alias user='myDisk0'/>
<address type='drive' controller='0' bus='0'
target='0' unit='0'/>
</disk>
Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com>
---
An alternative approach to:
https://www.redhat.com/archives/libvir-list/2017-September/msg00765.html
Honestly, I prefer this one as it's simpler and we don't have to care about
devices changing their aliases on cold plug. I mean, on cold (un-)plug we'd
have to regenerate the aliases so it might be hard to track certain device.
But with this approach, it's no problem.
Also, I'm not completely convinced about the name of @user attribute. So I'm
open for suggestions.
docs/schemas/domaincommon.rng | 13 +++++++---
src/conf/device_conf.c | 1 +
src/conf/device_conf.h | 1 +
src/conf/domain_conf.c | 20 ++++++++++-----
tests/genericxml2xmlindata/generic-user-alias.xml | 31 +++++++++++++++++++++++
tests/genericxml2xmltest.c | 2 ++
6 files changed, 59 insertions(+), 9 deletions(-)
create mode 100644 tests/genericxml2xmlindata/generic-user-alias.xml
diff --git a/docs/schemas/domaincommon.rng b/docs/schemas/domaincommon.rng
index bac371ea3..69c121ce9 100644
--- a/docs/schemas/domaincommon.rng
+++ b/docs/schemas/domaincommon.rng
@@ -5864,9 +5864,16 @@
</define>
<define name='alias'>
<element name='alias'>
- <attribute name='name'>
- <ref name='aliasName'/>
- </attribute>
+ <optional>
+ <attribute name='name'>
+ <ref name='aliasName'/>
+ </attribute>
+ </optional>
+ <optional>
+ <attribute name='user'>
+ <ref name='aliasName'/>
+ </attribute>
+ </optional>
</element>
<empty/>
</define>
diff --git a/src/conf/device_conf.c b/src/conf/device_conf.c
index d69f94fad..ced5db123 100644
--- a/src/conf/device_conf.c
+++ b/src/conf/device_conf.c
@@ -57,6 +57,7 @@ void
virDomainDeviceInfoClear(virDomainDeviceInfoPtr info)
{
VIR_FREE(info->alias);
+ VIR_FREE(info->user);
memset(&info->addr, 0, sizeof(info->addr));
info->type = VIR_DOMAIN_DEVICE_ADDRESS_TYPE_NONE;
VIR_FREE(info->romfile);
diff --git a/src/conf/device_conf.h b/src/conf/device_conf.h
index f87d6f1fc..08a9e57e3 100644
--- a/src/conf/device_conf.h
+++ b/src/conf/device_conf.h
@@ -135,6 +135,7 @@ typedef struct _virDomainDeviceInfo virDomainDeviceInfo;
typedef virDomainDeviceInfo *virDomainDeviceInfoPtr;
struct _virDomainDeviceInfo {
char *alias;
+ char *user; /* user defined ID for the device */
int type; /* virDomainDeviceAddressType */
union {
virPCIDeviceAddress pci;
diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index 87192eb2d..885825226 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -5756,6 +5756,8 @@ virDomainDeviceInfoFormat(virBufferPtr buf,
virDomainDeviceInfoPtr info,
unsigned int flags)
{
+ bool formatAlias = info->alias && !(flags &
VIR_DOMAIN_DEF_FORMAT_INACTIVE);
+
if ((flags & VIR_DOMAIN_DEF_FORMAT_ALLOW_BOOT) && info->bootIndex) {
virBufferAsprintf(buf, "<boot order='%u'",
info->bootIndex);
@@ -5764,9 +5766,13 @@ virDomainDeviceInfoFormat(virBufferPtr buf,
virBufferAddLit(buf, "/>\n");
}
- if (info->alias &&
- !(flags & VIR_DOMAIN_DEF_FORMAT_INACTIVE)) {
- virBufferAsprintf(buf, "<alias name='%s'/>\n",
info->alias);
+ if (formatAlias || info->user) {
+ virBufferAddLit(buf, "<alias");
+ if (formatAlias)
+ virBufferAsprintf(buf, " name='%s'", info->alias);
+ if (info->user)
+ virBufferAsprintf(buf, " user='%s'", info->user);
+ virBufferAddLit(buf, "/>\n");
}
if (info->mastertype == VIR_DOMAIN_CONTROLLER_MASTER_USB) {
@@ -6327,7 +6333,6 @@ virDomainDeviceInfoParseXML(xmlNodePtr node,
while (cur != NULL) {
if (cur->type == XML_ELEMENT_NODE) {
if (alias == NULL &&
- !(flags & VIR_DOMAIN_DEF_PARSE_INACTIVE) &&
virXMLNodeNameEqual(cur, "alias")) {
alias = cur;
} else if (address == NULL &&
@@ -6349,8 +6354,11 @@ virDomainDeviceInfoParseXML(xmlNodePtr node,
cur = cur->next;
}
- if (alias)
- info->alias = virXMLPropString(alias, "name");
+ if (alias) {
+ if (!(flags & VIR_DOMAIN_DEF_PARSE_INACTIVE))
+ info->alias = virXMLPropString(alias, "name");
+ info->user = virXMLPropString(alias, "user");
+ }
if (master) {
info->mastertype = VIR_DOMAIN_CONTROLLER_MASTER_USB;
diff --git a/tests/genericxml2xmlindata/generic-user-alias.xml
b/tests/genericxml2xmlindata/generic-user-alias.xml
new file mode 100644
index 000000000..025924442
--- /dev/null
+++ b/tests/genericxml2xmlindata/generic-user-alias.xml
@@ -0,0 +1,31 @@
+<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'/>
+ <alias user='myDisk0'/>
+ <address type='drive' controller='0' bus='0'
target='0' unit='0'/>
+ </disk>
+ <controller type='usb' index='0'>
+ <alias user='myController0'/>
+ </controller>
+ <controller type='ide' index='0'/>
+ <controller type='pci' index='0' model='pci-root'/>
+ <memballoon model='none'/>
+ </devices>
+</domain>
diff --git a/tests/genericxml2xmltest.c b/tests/genericxml2xmltest.c
index 0377a05e9..63a62f6a5 100644
--- a/tests/genericxml2xmltest.c
+++ b/tests/genericxml2xmltest.c
@@ -130,6 +130,8 @@ mymain(void)
DO_TEST_FULL("chardev-reconnect-invalid-mode", 0, false,
TEST_COMPARE_DOM_XML2XML_RESULT_FAIL_PARSE);
+ DO_TEST("user-alias");
+
virObjectUnref(caps);
virObjectUnref(xmlopt);
--
2.13.5