Commit Graph

143 Commits

Author SHA1 Message Date
Jiri Denemark
93d56e9df1 qemu: Add APIs for migrate-incoming QMP command
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2015-11-19 09:41:23 +01:00
Shivangi Dhir
7383b8cc06 qemu: Make virtType of type virDomainVirtType
Earlier virtType was of type int. After, introducing the enum VIR_DOMAIN_VIRT_NONE,
the type of virtType is modified to virDomainVirtType.
2015-09-25 15:34:09 -04:00
Peter Krempa
78aefb5275 qemu: monitor: Remove qemuMonitorGetBlockExtent
Now that qemuMonitorGetAllBlockStatsInfo collects also wr_highest_offset
the whole function can be killed.
2015-06-26 16:41:24 +02:00
Jiri Denemark
3a18bd2d7a qemu: Refactor qemuMonitorBlockJobInfo
"query-block-jobs" QMP command returns all running block jobs at once,
while qemuMonitorBlockJobInfo would only report one. This is not very
nice in case we need to check several block jobs. This patch refactors
the monitor code to always parse all block jobs and store them in a
hash.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2015-06-19 15:15:11 +02:00
Ján Tomko
c09e1729df Remove path argument from qemuMonitorJSONFindLinkPath
All the callers use "/" anyway.
2015-06-05 16:01:23 +02:00
Ján Tomko
5aca919b6c Introduce qemuMonitorJSONFindLinkPath
When traversing through the QOM tree, we're looking for
a link to a device, e.g.:
link<virtio-balloon-pci>

Introduce a helper that will format the link name at the start,
instead of doing it every time while recursing through the tree.
2015-06-05 16:00:51 +02:00
Ján Tomko
88710cee75 Move qemuMonitorFindObjectPath to qemu_monitor_json
This function is specific to the JSON monitor.
2015-06-05 15:55:22 +02:00
Peter Krempa
987b70777a qemu: monitor: Make qemuMonitorSetBalloon operate on unsinged long long 2015-06-03 09:42:08 +02:00
Peter Krempa
065a81082d qemu: blockPull: Refactor the rest of qemuDomainBlockJobImpl
Since it now handles only block pull code paths we can refactor it and
remove tons of cruft.
2015-04-14 10:00:56 +02:00
Peter Krempa
cfc0a3d4ce qemu: blockjob: Separate qemuDomainBlockJobAbort from qemuDomainBlockJobImpl
Sacrifice a few lines of code in favor of the code being more readable.
2015-04-14 10:00:56 +02:00
Peter Krempa
1344a74ef2 qemu: blockjob: Split qemuDomainBlockJobSetSpeed from qemuDomainBlockJobImpl
qemuDomainBlockJobImpl become an unmaintainable mess over the years of
adding new stuff to it. This patch starts splitting up individual
functions from it until it can be killed entirely.

In bulk this will add lines of code rather than delete them but it will
be traded for maintainability.
2015-04-14 10:00:56 +02:00
Peter Krempa
db37f3cc3a qemu: Clean up old leftovers in qemuMonitorDrivePivot
There are two leftover unused variables. Remove them and clean up the
fallout of the change.
2015-04-09 14:18:48 +02:00
Ján Tomko
9e48f6cf9f Rename qemuMonitorIOThreadsInfo* to qemuMonitorIOThreadInfo*
It only deals with a single thread.
2015-03-26 16:11:10 +01:00
Peter Krempa
5cdfaa31c4 qemu: memdev: Add infrastructure to load memory device information
When using 'dimm' memory devices with qemu, some of the information
like the slot number and base address need to be reloaded from qemu
after process start so that it reflects the actual state. The state then
allows to use memory devices across migrations.
2015-03-23 14:25:15 +01:00
Eric Blake
f9ea3d6011 qemu: read backing chain names from qemu
https://bugzilla.redhat.com/show_bug.cgi?id=1199182 documents that
after a series of disk snapshots into existing destination images,
followed by active commits of the top image, it is possible for
qemu 2.2 and earlier to end up tracking a different name for the
image than what it would have had when opening the chain afresh.
That is, when starting with the chain 'a <- b <- c', the name
associated with 'b' is how it was spelled in the metadata of 'c',
but when starting with 'a', taking two snapshots into 'a <- b <- c',
then committing 'c' back into 'b', the name associated with 'b' is
now the name used when taking the first snapshot.

Sadly, older qemu doesn't know how to treat different spellings of
the same filename as identical files (it uses strcmp() instead of
checking for the same inode), which means libvirt's attempt to
commit an image using solely the names learned from qcow2 metadata
fails with a cryptic:

error: internal error: unable to execute QEMU command 'block-commit': Top image file /tmp/images/c/../b/b not found

even though the file exists.  Trying to teach libvirt the rules on
which name qemu will expect is not worth the effort (besides, we'd
have to remember it across libvirtd restarts, and track whether a
file was opened via metadata or via snapshot creation for a given
qemu process); it is easier to just always directly ask qemu what
string it expects to see in the first place.

As a safety valve, we validate that any name returned by qemu
still maps to the same local file as we have tracked it, so that
a compromised qemu cannot accidentally cause us to act on an
incorrect file.

* src/qemu/qemu_monitor.h (qemuMonitorDiskNameLookup): New
prototype.
* src/qemu/qemu_monitor_json.h (qemuMonitorJSONDiskNameLookup):
Likewise.
* src/qemu/qemu_monitor.c (qemuMonitorDiskNameLookup): New function.
* src/qemu/qemu_monitor_json.c (qemuMonitorJSONDiskNameLookup)
(qemuMonitorJSONDiskNameLookupOne): Likewise.
* src/qemu/qemu_driver.c (qemuDomainBlockCommit)
(qemuDomainBlockJobImpl): Use it.

Signed-off-by: Eric Blake <eblake@redhat.com>
2015-03-17 11:57:53 -06:00
Peter Krempa
d3534a43e6 qemu: monitor: Kill qemuMonitorGetBlockStats(Info,ParamsNumber)
The functions and their QMP and HMP implementations are no longer needed
since everything is now done via the *AllStats functions.
2015-03-11 11:28:04 +01:00
Peter Krempa
4f6b6788c4 qemu: blockstats: Switch to caller allocated hash table
Allocate the hash table in the monitor wrapper function instead of the
worker itself so that the text monitor impl that will be added in the
next patch doesn't have to duplicate it.
2015-03-11 11:28:03 +01:00
Peter Krempa
32288fc9b9 qemu: monitor: Drop parsing of 'errs' from block info
The error count statistic is not supported by qemu, so there's no need
to pass the variables around if the result is ignored anyways.
2015-03-11 11:28:03 +01:00
Pavel Hrdina
ce745914b3 qemu_process: detect updated video ram size values from QEMU
QEMU internally updates the size of video memory if the domain XML had
provided too low memory size or there are some dependencies for a QXL
devices 'vgamem' and 'ram' size. We need to know about the changes and
store them into the status XML to not break migration or managedsave
through different libvirt versions.

The values would be loaded only if the "vgamem_mb" property exists for
the device.  The presence of the "vgamem_mb" also tells that the
"ram_size" and "vram_size" exists for QXL devices.

Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
2015-01-14 11:55:51 +01:00
Eric Blake
7b11f5e554 getstats: prepare monitor collection for recursion
A future patch will allow recursion into backing chains when
collecting block stats.  This patch should not change behavior,
but merely moves out the common code that will be reused once
recursion is enabled, and adds the parameter that will turn on
recursion.

* src/qemu/qemu_monitor.h (qemuMonitorGetAllBlockStatsInfo)
(qemuMonitorBlockStatsUpdateCapacity): Add recursion parameter,
although it is ignored for now.
* src/qemu/qemu_monitor.h (qemuMonitorGetAllBlockStatsInfo)
(qemuMonitorBlockStatsUpdateCapacity): Likewise.
* src/qemu/qemu_monitor_json.h
(qemuMonitorJSONGetAllBlockStatsInfo)
(qemuMonitorJSONBlockStatsUpdateCapacity): Likewise.
* src/qemu/qemu_monitor_json.c
(qemuMonitorJSONGetAllBlockStatsInfo)
(qemuMonitorJSONBlockStatsUpdateCapacity): Add parameter, and
split...
(qemuMonitorJSONGetOneBlockStatsInfo)
(qemuMonitorJSONBlockStatsUpdateCapacityOne): ...into helpers.
(qemuMonitorJSONGetBlockStatsInfo): Update caller.
* src/qemu/qemu_driver.c (qemuDomainGetStatsBlock): Update caller.
* src/qemu/qemu_migration.c (qemuMigrationCookieAddNBD): Likewise.

Signed-off-by: Eric Blake <eblake@redhat.com>
2014-12-16 16:08:04 -07:00
Peter Krempa
e9a4506963 qemu: monitor: Rename and improve qemuMonitorGetPtyPaths
To unify future additions that require information from "query-chardev"
rename qemuMonitorGetPtyPaths and friends to qemuMonitorGetChardevInfo
and move the allocation of the returned hash into the top level
function.
2014-11-21 11:00:10 +01:00
Jiri Denemark
ab393383c8 qemu: Always set migration capabilities
We used to set migration capabilities only when a user asked for them in
flags. This is fine when migration succeeds since the QEMU process is
killed in the end but in case migration fails or if it's cancelled, some
capabilities may remain turned on with no way to turn them off. To fix
that, migration capabilities have to be turned on if requested but
explicitly turned off in case they were not requested but QEMU supports
them.

https://bugzilla.redhat.com/show_bug.cgi?id=1163953
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2014-11-13 20:33:28 +01:00
Matthias Gatto
d506a51aeb qemu: Add bps_max and friends qemu driver
Add support for bps_max and friends in the driver part.
In the part checking if a qemu is running, check if the running binary
support bps_max, if not print an error message, if yes add it to
"info" variable

Signed-off-by: Matthias Gatto <matthias.gatto@outscale.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2014-11-10 17:18:17 +01:00
Peter Krempa
6908f8cab3 qemu: monitor: Add functions for object hot-add/remove
To allow live modification of device backends in qemu libvirt needs to
be able to hot-add/remove "objects". Add monitor backend functions to
allow this.

This function will be used for hot-add/remove of RNG backends,
IOThreads, memory backing objects, etc.
2014-10-15 10:27:50 +02:00
Laine Stump
ab989962d4 qemu: qemuMonitorQueryRxFilter - retrieve guest netdev rx-filter
This function can be called at any time to get the current status of a
guest's network device rx-filter. In particular it is useful to call
after libvirt recieves a NIC_RX_FILTER_CHANGED event - this event only
tells you that something has changed in the rx-filter, the details are
retrieved with the query-rx-filter monitor command (only available in
the json monitor). The command sent to the qemu monitor looks like this:

  {"execute":"query-rx-filter", "arguments": {"name":"net2"} }'

and the results will look something like this:

{
    "return": [
        {
            "promiscuous": false,
            "name": "net2",
            "main-mac": "52:54:00:98:2d:e3",
            "unicast": "normal",
            "vlan": "normal",
            "vlan-table": [
                42,
                0
            ],
            "unicast-table": [

            ],
            "multicast": "normal",
            "multicast-overflow": false,
            "unicast-overflow": false,
            "multicast-table": [
                "33:33:ff:98:2d:e3",
                "01:80:c2:00:00:21",
                "01:00:5e:00:00:fb",
                "33:33:ff:98:2d:e2",
                "01:00:5e:00:00:01",
                "33:33:00:00:00:01"
            ],
            "broadcast-allowed": false
        }
    ],
    "id": "libvirt-14"
}

This is all parsed from JSON into a virNetDevRxFilter object for
easier consumption. (unicast-table is usually empty, but is also an
array of mac addresses similar to multicast-table).

(NB: LIBNL_CFLAGS was added to tests/Makefile.am because virnetdev.h
now includes util/virnetlink.h, which includes netlink/msg.h when
appropriate. Without LIBNL_CFLAGS, gcc can't find that file (if
libnl/netlink isn't available, LIBNL_CFLAGS will be empty and
virnetlink.h won't try to include netlink/msg.h anyway).)
2014-10-06 13:32:38 -04:00
Peter Krempa
8caded6b8e qemu: monitor: Add helper function to fill physical/virtual image size
While our code gathers block stats via "query-blockstats" some
information need to be gathered via "query-block". Add a helper function
that will update the blockstats structure if requested.
2014-10-01 10:58:33 +02:00
Peter Krempa
96c0f57a82 qemu: monitor: return block stats data as a hash to avoid disk mixup
The current block stats code matched up the disk name with the actual
stats by the order in the data returned from qemu. This unfortunately
isn't right as qemu may return the disks in any order. Fix this by
returning a hash of stats and index them by the disk alias.
2014-09-30 11:01:55 +02:00
Jiri Denemark
b3fd95e368 qemu: Add RDMA migration capabilities 2014-09-23 08:11:49 +02:00
Francesco Romani
290e3c6b07 qemu: bulk stats: implement block group
This patch implements the VIR_DOMAIN_STATS_BLOCK group of statistics.

To do so, a helper function to get the block stats of all the disks of
a domain is added.

Signed-off-by: Francesco Romani <fromani@redhat.com>
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
2014-09-17 18:15:10 +02:00
John Ferlan
4cf6bfab4c qemu: Issue query-iothreads and to get list of active IOThreads
Generate infrastructure and test to handle fetching the QMP
IOThreads data.
2014-09-15 13:18:56 -04:00
Eric Blake
eef91f9470 blockcopy: add qemu implementation of new tunables
Upstream qemu 1.4 added some drive-mirror tunables not present
when it was first introduced in 1.3.  Management apps may want
to set these in some cases (for example, without tuning
granularity down to sector size, a copy may end up occupying
more bytes than the original because an entire cluster is
copied even when only a sector within the cluster is dirty,
although tuning it down results in more CPU time to do the
copy).  I haven't personally needed to use the parameters, but
since they exist, and since the new API supports virTypedParams,
we might as well expose them.

Since the tuning parameters aren't often used, and omitted from
the QMP command when unspecified, I think it is safe to rely on
qemu 1.3 to issue an error about them being unsupported, rather
than trying to create a new capability bit in libvirt.

Meanwhile, all versions of qemu from 1.4 to 2.1 have a bug where
a bad granularity (such as non-power-of-2) gives a poor message:
error: internal error: unable to execute QEMU command 'drive-mirror': Invalid parameter 'drive-virtio-disk0'

because of abuse of QERR_INVALID_PARAMETER (which is supposed to
name the parameter that was given a bad value, rather than the
value passed to some other parameter).  I don't see that a
capability check will help, so we'll just live with it (and it
has since been improved in upstream qemu).

* src/qemu/qemu_monitor.h (qemuMonitorDriveMirror): Add
parameters.
* src/qemu/qemu_monitor.c (qemuMonitorDriveMirror): Likewise.
* src/qemu/qemu_monitor_json.h (qemuMonitorJSONDriveMirror):
Likewise.
* src/qemu/qemu_monitor_json.c (qemuMonitorJSONDriveMirror):
Likewise.
* src/qemu/qemu_driver.c (qemuDomainBlockCopyCommon): Likewise.
(qemuDomainBlockRebase, qemuDomainBlockCopy): Adjust callers.
* src/qemu/qemu_migration.c (qemuMigrationDriveMirror): Likewise.
* tests/qemumonitorjsontest.c (qemuMonitorJSONDriveMirror): Likewise.

Signed-off-by: Eric Blake <eblake@redhat.com>
2014-09-12 08:11:11 -06:00
Eric Blake
db33cc2494 blockjob: allow finer bandwidth tuning for query
While reviewing the new virDomainBlockCopy API, Peter Krempa
pointed out that our existing design of using MiB/s for block
job bandwidth is rather coarse, especially since qemu tracks
it in bytes/s; so virDomainBlockCopy only accepts bytes/s.
But once the new API is implemented for qemu, we will be in
the situation where it is possible to set a value that cannot
be accurately reflected back to the user, because the existing
virDomainGetBlockJobInfo defaults to the coarser units.

Fortunately, we have an escape hatch; and one that has already
served us well in the past: we can use the flags argument to
specify which scale to use (see virDomainBlockResize for prior
art).  This patch fixes the query side of the API; made easier
by previous patches that split the query side out from the
modification code.  Later patches will address the virsh
interface, as well retrofitting all other blockjob APIs to
also accept a flag for toggling bandwidth units.

* include/libvirt/libvirt.h.in (_virDomainBlockJobInfo)
(VIR_DOMAIN_BLOCK_COPY_BANDWIDTH): Document sizing issues.
(virDomainBlockJobInfoFlags): New enum.
* src/libvirt.c (virDomainGetBlockJobInfo): Document new flag.
* src/qemu/qemu_monitor.h (qemuMonitorBlockJobInfo): Add parameter.
* src/qemu/qemu_monitor.c (qemuMonitorBlockJobInfo): Likewise.
* src/qemu/qemu_monitor_json.h (qemuMonitorJSONBlockJobInfo):
Likewise.
* src/qemu/qemu_monitor_json.c (qemuMonitorJSONBlockJobInfo)
(qemuMonitorJSONGetBlockJobInfoOne): Likewise. Don't scale here.
* src/qemu/qemu_migration.c (qemuMigrationDriveMirror): Update
callers.
* src/qemu/qemu_driver.c (qemuDomainBlockPivot)
(qemuDomainBlockJobImpl): Likewise.
(qemuDomainGetBlockJobInfo): Likewise, and support new flag.

Signed-off-by: Eric Blake <eblake@redhat.com>
2014-09-05 11:20:12 -06:00
Eric Blake
ced813652b blockjob: split out block info monitor handling
Another layer of overly-multiplexed code that deserves to be
split into obviously separate paths for query vs. modify.
This continues the cleanup started in commit cefe0ba.

In the process, make some tweaks to simplify the logic when
parsing the JSON reply.  There should be no user-visible
semantic changes.

* src/qemu/qemu_monitor.h (qemuMonitorBlockJob): Drop parameter.
(qemuMonitorBlockJobInfo): New prototype.
(BLOCK_JOB_INFO): Drop enum.
* src/qemu/qemu_monitor_json.h (qemuMonitorJSONBlockJob)
(qemuMonitorJSONBlockJobInfo): Likewise.
* src/qemu/qemu_monitor.c (qemuMonitorBlockJob): Split...
(qemuMonitorBlockJobInfo): ...into second function.
* src/qemu/qemu_monitor_json.c (qemuMonitorJSONBlockJob): Move
block info portions...
(qemuMonitorJSONGetBlockJobInfo): ...here, and rename...
(qemuMonitorJSONBlockJobInfo): ...and export.
(qemuMonitorJSONGetBlockJobInfoOne): Alter return semantics.
* src/qemu/qemu_driver.c (qemuDomainBlockPivot)
(qemuDomainBlockJobImpl, qemuDomainGetBlockJobInfo): Adjust
callers.
* src/qemu/qemu_migration.c (qemuMigrationDriveMirror)
(qemuMigrationCancelDriveMirror): Likewise.

Signed-off-by: Eric Blake <eblake@redhat.com>
2014-09-05 10:37:08 -06:00
Michal Privoznik
b606bbb416 qemu: Issue rtc-reset-reinjection command after guest-set-time
https://bugzilla.redhat.com/show_bug.cgi?id=1103245

An advice appeared there on the qemu-devel list [1]. When a domain is
suspended and then resumed guest kernel is not aware of this. So we've
introduced virDomainSetTime API that resets the time within guest
using qemu-ga. On the other hand, qemu itself is trying to make RTC
beat faster to catch the difference. But if we don't tell qemu that
guest's time was reset via the other method, both mechanisms are
applied resulting in again wrong guest time. In order to avoid summing
both corrections we need to tell qemu that it should not use the RTC
injection if the guest time is set via guest agent.

1: http://www.mail-archive.com/qemu-devel@nongnu.org/msg236435.html

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2014-08-20 14:20:05 +02:00
Martin Kletzander
7bc1db5a1d qemu: allow qmp probing for cmdline options without params
That can be lately achieved with by having .param == NULL in the
virQEMUCapsCommandLineProps struct.

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
2014-07-16 20:15:46 +02:00
Peter Krempa
a448713a45 qemu: monitor: Add support for backing name specification for block-stream
To allow changing the name that is recorded in the top of the current
image chain used in a block pull/rebase operation, we need to specify
the backing name to qemu. This is done via the "backing-file" attribute
to the block-stream commad.
2014-07-04 13:00:17 +02:00
Peter Krempa
c29b652912 qemu: monitor: Add argument for specifying backing name for block commit
To allow changing the name that is recorded in the overlay of the TOP
image used in a block commit operation, we need to specify the backing
name to qemu. This is done via the "backing-file" attribute to the
block-commit command.
2014-07-04 13:00:16 +02:00
Eric Blake
47549d5a17 blockjob: allow omitted arguments to QMP block-commit
We are about to turn on support for active block commit.  Although
qemu 2.0 was the first version to mostly support it, that version
mis-handles 0-length files, and doesn't have anything available for
easy probing.  But qemu 2.1 fixed bugs, and made life simpler by
letting the 'top' argument be optional.  Unless someone begs for
active commit with qemu 2.0, for now we are just going to enable
it only by probing for qemu 2.1 behavior (anyone backporting active
commit can also backport the optional argument behavior).  This
requires qemu.git commit 7676e2c597000eff3a7233b40cca768b358f9bc9.

Although all our actual uses of block-commit supply arguments for
both base and top, we can omit both arguments and use a bogus
device string to trigger an interesting behavior in qemu.  All QMP
commands first do argument validation, failing with GenericError
if a mandatory argument is missing.  Once that passes, the code
in the specific command gets to do further checking, and the qemu
developers made sure that if device is the only supplied argument,
then the block-commit code will look up the device first, with a
failure of DeviceNotFound, before attempting any further argument
validation (most other validations fail with GenericError).  Thus,
the category of error class can reliably be used to decipher
whether the top argument was optional, which in turn implies a
working active commit.  Since we expect our bogus device string to
trigger an error either way, the code is written to return a
distinct return value without spamming the logs.

* src/qemu/qemu_monitor.h (qemuMonitorSupportsActiveCommit): New
prototype.
* src/qemu/qemu_monitor.c (qemuMonitorSupportsActiveCommit):
Implement it.
* src/qemu/qemu_monitor_json.h (qemuMonitorJSONBlockCommit):
Allow NULL for top and base, for probing purposes.
* src/qemu/qemu_monitor_json.c (qemuMonitorJSONBlockCommit):
Likewise, implementing the probe.
* tests/qemumonitorjsontest.c (mymain): Enable...
(testQemuMonitorJSONqemuMonitorSupportsActiveCommit): ...a new test.

Signed-off-by: Eric Blake <eblake@redhat.com>
2014-07-03 14:19:51 -06:00
Julio Faracco
5a2bd4c917 conf: more enum cleanups in "src/conf/domain_conf.h"
In "src/conf/domain_conf.h" there are many enum declarations. The
cleanup in this header filer was started, but it wasn't enough and
there are many other files that has enum variables declared. So, the
commit was starting to be big. This commit finish the cleanup in this
header file and in other files that has enum variables, parameters,
or functions declared.

Signed-off-by: Julio Faracco <jcfaracco@gmail.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2014-06-02 15:32:58 -06:00
Qiao Nuohan
8c023e3187 qemu: add support for virDomainCoreDumpWithFormat API
This patch makes qemu driver support virDomainCoreDumpWithFormat API.

Signed-off-by: Qiao Nuohan <qiaonuohan@cn.fujitsu.com>
2014-03-24 14:14:14 -06:00
Qiao Nuohan
43177e2fd0 qemu: add qemuMonitorGetDumpGuestMemoryCapability
This patch adds qemuMonitorGetDumpGuestMemoryCapability, which is used to check
whether the specified dump-guest-memory format is supported by qemu.

Signed-off-by: Qiao Nuohan <qiaonuohan@cn.fujitsu.com>
2014-03-24 14:14:14 -06:00
Eric Blake
359f4b11a6 qemu: don't munge user input during block commit
While investigating https://bugzilla.redhat.com/show_bug.cgi?id=1061827
I noticed that we pass user input unscathed for block-pull, but
always pass a canonical absolute name through for block-commit.
[Note that we probably _ought_ to validate that the user's request
for block-pull actually matches the backing chain, the way we already
do for block-commit - but that's a separate issue.  Further note that
the ability to pass user input through unscathed allows backdoors
such as specifying a backing image that is a network URI such as
a gluster disk, instead of forcing things to the local file system;
which is an area still under active investigation on whether libvirt
needs to behave differently for network disks.]

Since qemu may write the name that the user passed in as the backing
file, a user may have a reason to want a relative file name passed
through to qemu, and always munging things to absolute prevents that.

Put another way, if you have the backing chain:

[A] <- [B(back=./A)] <- [C(back=./B)]

and commit B into A (virsh blockcommit $dom vda --base A --top B),
the metadata of C will have to be re-written. But should it be
rewritten as [C(back=./A)] or as [C(back=/path/to/A)]?  Still up in
the air is whether qemu's decision should be based on whether B
and/or C had relative paths, or on whether the --base and/or
--top arguments to the command were relative paths; but if we always
pass a canonical name, we've prevented the spelling of the command
arguments from being part of the hueristics that qemu uses.

I also audited the code, and verified that we never call
qemuMonitorBlockCommit() with a NULL base, either before or after
the change to qemu_driver.c.

* src/qemu/qemu_driver.c (qemuDomainBlockCommit): Preserve user's
spelling, since absolute vs. relative matters to qemu.
* src/qemu/qemu_monitor.h (qemuMonitorBlockCommit): Base is never
null.
* src/qemu/qemu_monitor.c (qemuMonitorBlockCommit): Likewise.
* src/qemu/qemu_monitor_json.h (qemuMonitorJSONBlockCommit):
Likewise.
* src/qemu/qemu_monitor_json.c (qemuMonitorJSONBlockCommit):
Likewise.

Signed-off-by: Eric Blake <eblake@redhat.com>
2014-03-11 17:53:19 -06:00
Peter Krempa
a6a6f84af9 qemu: Change return type of qemuMonitorGetGuestCPU()
To allow returning more granular errors, change the error type to an
integer.
2013-11-12 19:35:51 +01:00
Jiri Denemark
3afde0756f qemu: Add monitor APIs to fetch CPUID data from QEMU
The qemu monitor supports retrieval of actual CPUID bits presented to
the guest using QMP monitor. Add APIs to extract these information and
tests for them.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
2013-11-08 09:44:36 +01:00
John Ferlan
0cacffac64 Remove ATTRIBUTE_NONNULL(3) from qemuMonitorJSONDrivePivot
The header definition didn't match the function declaration, so adjusted
header to reflect the definition.

Found during a Coverity build where STATIC_ANALYSIS is enabled resulting
in the internal.h adding __nonnull__ handling to arguments.

Commit '6d264c91' added support for the qemuMonitorJSONDrivePivot() and
commit 'fbc3adc9' added a corresponding test which ended up triggering
the build failure which I didn't notice until today!
2013-10-17 19:36:42 -04:00
Jiri Denemark
58b147ad07 qemu: Introduce qemuMonitorGetDeviceAliases
This API provides a NULL-terminated list of devices which are currently
attached to a QEMU domain.
2013-07-19 18:45:47 +02:00
John Ferlan
ab60062117 Add capability to fetch balloon stats
This patch will add the qemuMonitorJSONGetMemoryStats() to execute a
"guest-stats" on the balloonpath using "get-qom" replacing the former
mechanism which looked through the "query-ballon" returned data for
the fields.  The "query-balloon" code only returns 'actual' memory.
Rather than duplicating the existing code, have the JSON API use the
GetBalloonInfo API.

A check in the qemuMonitorGetMemoryStats() will be made to ensure the
balloon driver path has been set.  Since the underlying JSON code can
return data not associated with the balloon driver, we don't fail on
a failure to get the balloonpath.  Of course since we've made the check,
we can then set the ballooninit flag.  Getting the path here is primarily
due to the process reconnect path which doesn't attempt to set the
collection period.
2013-07-16 08:44:52 -04:00
John Ferlan
ffdf82a9da Determine whether to start balloon memory stats gathering.
At vm startup and attach attempt to set the balloon driver statistics
collection period based on the value found in the domain xml file. This
is not done at reconnect since it's possible that a collection period
was set on the live guest and making the set period call would reset to
whatever value is stored in the config file.

Setting the stats collection period has a side effect of searching through
the qom-list output for the virtio balloon driver and making sure that it
has the right properties in order to allow setting of a collection period
and eventually fetching of statistics.

The walk through the qom-list is expensive and thus the balloonpath will
be saved in the monitor private structure as well as a flag indicating
that the initialization has already been attempted (in the event that a
path is not found, no sense to keep checking).

This processing model conforms to the qom object model model which
requires setting object properties after device startup. That is, it's
not possible to pass the period along via the startup code as it won't
be recognized.
2013-07-16 08:44:52 -04:00
John Ferlan
50336d871a Add qemuMonitorJSONSetObjectProperty() method for QMP qom-set command
Add a new qemuMonitorJSONSetObjectProperty() method to support invocation
of the 'qom-set' JSON monitor command with a provided path, property, and
expected data type to set.

NOTE: The set API was added only for the purpose of the qemumonitorjsontest

The test code uses the same "/machine/i440fx" property as the get test and
attempts to set the "realized" property to "true" (which it should be set
at anyway).
2013-07-15 12:26:16 -04:00
John Ferlan
bdce278984 Add qemuMonitorJSONGetObjectProperty() method for QMP qom-get command
Add a new qemuMonitorJSONGetObjectProperty() method to support invocation
of the 'qom-get' JSON monitor command with a provided path, property, and
expected data type return. The qemuMonitorJSONObjectProperty is similar to
virTypedParameter; however, a future patch will extend it a bit to include
a void pointer to balloon driver statistic data.

NOTE: The ObjectProperty structures and API are added only for the
      purpose of the qemumonitorjsontest

The provided test will execute a qom-get on "/machine/i440fx" which will
return a property "realized".
2013-07-15 12:26:16 -04:00