[libvirt] [PATCHv3] LXC: Fix handling of RAM filesystem size units
Since 76b644c when the support for RAM filesystems was introduced, libvirt accepted the following XML: <source usage='1024' unit='KiB'/> This was parsed correctly and internally stored in bytes, but it was formatted as (with an extra 's'): <source usage='1024' units='KiB'/> When read again, this was treated as if the units were missing, meaning libvirt was unable to parse its own XML correctly. The usage attribute was documented as being in KiB, but it was not scaled if the unit was missing. Transient domains still worked, because this was balanced by an extra 'k' in the mount options. This patch: Changes the parser to use 'units' instead of 'unit', as the latter was never documented (fixing persistent domains). Removes the extra 'k' from the tmpfs mount options, which is needed because now we parse our own XML correctly. Changes the default input unit to KiB to match documentation, fixing: https://bugzilla.redhat.com/show_bug.cgi?id=1015689 --- v1: https://www.redhat.com/archives/libvir-list/2013-October/msg00361.html v2: keeps the output unit KiB changes the default input unit to KiB accepts 'units' as well as 'unit' in input XML v3: drop 'unit' completely as it was never documented docs/formatdomain.html.in | 6 +++-- docs/schemas/domaincommon.rng | 2 +- src/conf/domain_conf.c | 9 ++++--- src/lxc/lxc_container.c | 2 +- tests/domainschematest | 2 +- tests/lxcxml2xmldata/lxc-filesystem-ram.xml | 33 ++++++++++++++++++++++++++ tests/lxcxml2xmloutdata/lxc-filesystem-ram.xml | 33 ++++++++++++++++++++++++++ tests/lxcxml2xmltest.c | 1 + 8 files changed, 78 insertions(+), 10 deletions(-) create mode 100644 tests/lxcxml2xmldata/lxc-filesystem-ram.xml create mode 100644 tests/lxcxml2xmloutdata/lxc-filesystem-ram.xml diff --git a/docs/formatdomain.html.in b/docs/formatdomain.html.in index 3689399..8f74487 100644 --- a/docs/formatdomain.html.in +++ b/docs/formatdomain.html.in @@ -2213,7 +2213,8 @@ <dd> An in-memory filesystem, using memory from the host OS. The source element has a single attribute <code>usage</code> - which gives the memory usage limit in kibibytes. Only used + which gives the memory usage limit in KiB, unless units + are specified by the <code>units</code> attribute. Only used by LXC driver. <span class="since"> (since 0.9.13)</span></dd> <dt><code>type='bind'</code></dt> @@ -2279,7 +2280,8 @@ <code>name</code> attribute must be used with <code>type='template'</code>, and the <code>dir</code> attribute must be used with <code>type='mount'</code>. The <code>usage</code> attribute - is used with <code>type='ram'</code> to set the memory limit in KB. + is used with <code>type='ram'</code> to set the memory limit in KiB, + unless units are specified by the <code>units</code> attribute. </dd> <dt><code>target</code></dt> diff --git a/docs/schemas/domaincommon.rng b/docs/schemas/domaincommon.rng index 5c5301d..10b017f 100644 --- a/docs/schemas/domaincommon.rng +++ b/docs/schemas/domaincommon.rng @@ -1732,7 +1732,7 @@ <ref name="unsignedLong"/> </attribute> <optional> - <attribute name='unit'> + <attribute name='units'> <ref name='unit'/> </attribute> </optional> diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c index 0d63845..e3737bc 100644 --- a/src/conf/domain_conf.c +++ b/src/conf/domain_conf.c @@ -5916,7 +5916,7 @@ virDomainFSDefParseXML(xmlNodePtr node, char *accessmode = NULL; char *wrpolicy = NULL; char *usage = NULL; - char *unit = NULL; + char *units = NULL; ctxt->node = node; @@ -5972,7 +5972,7 @@ virDomainFSDefParseXML(xmlNodePtr node, source = virXMLPropString(cur, "name"); else if (def->type == VIR_DOMAIN_FS_TYPE_RAM) { usage = virXMLPropString(cur, "usage"); - unit = virXMLPropString(cur, "unit"); + units = virXMLPropString(cur, "units"); } } else if (!target && xmlStrEqual(cur->name, BAD_CAST "target")) { @@ -6042,8 +6042,7 @@ virDomainFSDefParseXML(xmlNodePtr node, usage); goto error; } - if (unit && - virScaleInteger(&def->usage, unit, + if (virScaleInteger(&def->usage, units, 1024, ULLONG_MAX) < 0) goto error; } @@ -6065,7 +6064,7 @@ cleanup: VIR_FREE(accessmode); VIR_FREE(wrpolicy); VIR_FREE(usage); - VIR_FREE(unit); + VIR_FREE(units); VIR_FREE(format); return def; diff --git a/src/lxc/lxc_container.c b/src/lxc/lxc_container.c index b1f429c..7c722cc 100644 --- a/src/lxc/lxc_container.c +++ b/src/lxc/lxc_container.c @@ -1428,7 +1428,7 @@ static int lxcContainerMountFSTmpfs(virDomainFSDefPtr fs, VIR_DEBUG("usage=%lld sec=%s", fs->usage, sec_mount_options); if (virAsprintf(&data, - "size=%lldk%s", fs->usage, sec_mount_options) < 0) + "size=%lld%s", fs->usage, sec_mount_options) < 0) goto cleanup; if (virFileMakePath(fs->dst) < 0) { diff --git a/tests/domainschematest b/tests/domainschematest index 0e360ca..9ebf0b9 100755 --- a/tests/domainschematest +++ b/tests/domainschematest @@ -7,7 +7,7 @@ DIRS="" DIRS="$DIRS domainschemadata qemuxml2argvdata sexpr2xmldata" DIRS="$DIRS xmconfigdata xml2sexprdata qemuxml2xmloutdata " -DIRS="$DIRS lxcxml2xmldata" +DIRS="$DIRS lxcxml2xmldata lxcxml2xmloutdata" SCHEMA="domain.rng" check_schema "$DIRS" "$SCHEMA" diff --git a/tests/lxcxml2xmldata/lxc-filesystem-ram.xml b/tests/lxcxml2xmldata/lxc-filesystem-ram.xml new file mode 100644 index 0000000..002fde6 --- /dev/null +++ b/tests/lxcxml2xmldata/lxc-filesystem-ram.xml @@ -0,0 +1,33 @@ +<domain type='lxc'> + <name>demo</name> + <uuid>8369f1ac-7e46-e869-4ca5-759d51478066</uuid> + <memory unit='KiB'>500000</memory> + <currentMemory unit='KiB'>500000</currentMemory> + <vcpu placement='static'>1</vcpu> + <os> + <type arch='x86_64'>exe</type> + <init>/bin/sh</init> + </os> + <clock offset='utc'/> + <on_poweroff>destroy</on_poweroff> + <on_reboot>restart</on_reboot> + <on_crash>destroy</on_crash> + <devices> + <emulator>/usr/libexec/libvirt_lxc</emulator> + <filesystem type='ram'> + <source usage='1048576'/> + <target dir='/mnt/mississippi'/> + </filesystem> + <filesystem type='ram'> + <source usage='1048576' units='bytes'/> + <target dir='/mnt/antananarivo'/> + </filesystem> + <filesystem type='ram'> + <source usage='1024' units='KiB'/> + <target dir='/mnt/ouagadougou'/> + </filesystem> + <console type='pty'> + <target type='lxc' port='0'/> + </console> + </devices> +</domain> diff --git a/tests/lxcxml2xmloutdata/lxc-filesystem-ram.xml b/tests/lxcxml2xmloutdata/lxc-filesystem-ram.xml new file mode 100644 index 0000000..d2369a2 --- /dev/null +++ b/tests/lxcxml2xmloutdata/lxc-filesystem-ram.xml @@ -0,0 +1,33 @@ +<domain type='lxc'> + <name>demo</name> + <uuid>8369f1ac-7e46-e869-4ca5-759d51478066</uuid> + <memory unit='KiB'>500000</memory> + <currentMemory unit='KiB'>500000</currentMemory> + <vcpu placement='static'>1</vcpu> + <os> + <type arch='x86_64'>exe</type> + <init>/bin/sh</init> + </os> + <clock offset='utc'/> + <on_poweroff>destroy</on_poweroff> + <on_reboot>restart</on_reboot> + <on_crash>destroy</on_crash> + <devices> + <emulator>/usr/libexec/libvirt_lxc</emulator> + <filesystem type='ram' accessmode='passthrough'> + <source usage='1048576' units='KiB'/> + <target dir='/mnt/mississippi'/> + </filesystem> + <filesystem type='ram' accessmode='passthrough'> + <source usage='1024' units='KiB'/> + <target dir='/mnt/antananarivo'/> + </filesystem> + <filesystem type='ram' accessmode='passthrough'> + <source usage='1024' units='KiB'/> + <target dir='/mnt/ouagadougou'/> + </filesystem> + <console type='pty'> + <target type='lxc' port='0'/> + </console> + </devices> +</domain> diff --git a/tests/lxcxml2xmltest.c b/tests/lxcxml2xmltest.c index 5846ab0..1692e4b 100644 --- a/tests/lxcxml2xmltest.c +++ b/tests/lxcxml2xmltest.c @@ -136,6 +136,7 @@ mymain(void) DO_TEST("systemd"); DO_TEST("hostdev"); DO_TEST("disk-formats"); + DO_TEST_DIFFERENT("filesystem-ram"); virObjectUnref(caps); virObjectUnref(xmlopt); -- 1.8.1.5
On 10/09/2013 08:13 AM, Ján Tomko wrote:
Since 76b644c when the support for RAM filesystems was introduced, libvirt accepted the following XML: <source usage='1024' unit='KiB'/>
This was parsed correctly and internally stored in bytes, but it was formatted as (with an extra 's'): <source usage='1024' units='KiB'/> When read again, this was treated as if the units were missing, meaning libvirt was unable to parse its own XML correctly.
Also mention that programs in the wild parse and then pass in the variant with the extra 's'.
The usage attribute was documented as being in KiB, but it was not scaled if the unit was missing. Transient domains still worked, because this was balanced by an extra 'k' in the mount options.
This patch: Changes the parser to use 'units' instead of 'unit', as the latter was never documented (fixing persistent domains).
Removes the extra 'k' from the tmpfs mount options, which is needed because now we parse our own XML correctly.
Changes the default input unit to KiB to match documentation, fixing: https://bugzilla.redhat.com/show_bug.cgi?id=1015689 ---
I think we're finally at a sane state. ACK with one nit:
+++ b/src/lxc/lxc_container.c @@ -1428,7 +1428,7 @@ static int lxcContainerMountFSTmpfs(virDomainFSDefPtr fs, VIR_DEBUG("usage=%lld sec=%s", fs->usage, sec_mount_options);
if (virAsprintf(&data, - "size=%lldk%s", fs->usage, sec_mount_options) < 0) + "size=%lld%s", fs->usage, sec_mount_options) < 0)
Please also modify the .h file that declares fs->usage to add a comment that we are storing it in-memory as bytes. -- Eric Blake eblake redhat com +1-919-301-3266 Libvirt virtualization library http://libvirt.org
On 10/09/2013 04:58 PM, Eric Blake wrote:
On 10/09/2013 08:13 AM, Ján Tomko wrote:
Since 76b644c when the support for RAM filesystems was introduced, libvirt accepted the following XML: <source usage='1024' unit='KiB'/>
This was parsed correctly and internally stored in bytes, but it was formatted as (with an extra 's'): <source usage='1024' units='KiB'/> When read again, this was treated as if the units were missing, meaning libvirt was unable to parse its own XML correctly.
Also mention that programs in the wild parse and then pass in the variant with the extra 's'.
...
I think we're finally at a sane state.
ACK with one nit:
Pushed with the added comment and amended commit message. Jan
+++ b/src/lxc/lxc_container.c @@ -1428,7 +1428,7 @@ static int lxcContainerMountFSTmpfs(virDomainFSDefPtr fs, VIR_DEBUG("usage=%lld sec=%s", fs->usage, sec_mount_options);
if (virAsprintf(&data, - "size=%lldk%s", fs->usage, sec_mount_options) < 0) + "size=%lld%s", fs->usage, sec_mount_options) < 0)
Please also modify the .h file that declares fs->usage to add a comment that we are storing it in-memory as bytes.
participants (2)
-
Eric Blake -
Ján Tomko