26689 Commits

Author SHA1 Message Date
Ján Tomko
f84c7c67d5 qemu: eliminate ret variable in qemuExtTPMStart
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
2020-01-28 13:32:27 +01:00
Ján Tomko
06160f6708 qemu: eliminate ret variable in qemuExtTPMStartEmulator
Now that the cleanup section is empty, eliminate the cleanup
label as well as the 'ret' variable.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
2020-01-28 13:32:27 +01:00
Ján Tomko
ebe9c31f41 qemu: use g_auto in qemuExtTPMStartEmulator
Use the g_auto macros wherever possible to eliminate the cleanup
section.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
2020-01-28 13:32:27 +01:00
Ján Tomko
3efdbae5bf conf: use virXMLFormatElement in virDomainFSDefFormat
Use the virXMLFormatElement helper to format the driver element
to simplify adding further sub-elements.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
2020-01-28 10:31:41 +01:00
Andrea Bolognani
c8a3a5d79b qemu_shim: Update temporary directory template
The template still references libvirt-qemu-shim, which was at one
point the name used to refer to what we now know as virt-qemu-run.

Signed-off-by: Andrea Bolognani <abologna@redhat.com>
2020-01-27 17:57:43 +01:00
Andrea Bolognani
7dca28e229 qemu_shim: Fix typos
Signed-off-by: Andrea Bolognani <abologna@redhat.com>
2020-01-27 17:57:08 +01:00
Ján Tomko
c07ef7c563 qemu: snapshot: go through cleanup on error
A recent commit added an error check for too-nested backing chains
followed by a return, even though errors above jump to cleanup.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Fixes: b168fa88b85dec181882816ab65a59a6c4500667
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
2020-01-27 17:36:05 +01:00
Ján Tomko
26a42e7315 qemu_shim: cosmetic fixes
Remove bogus G_GNUC_UNUSED attribute and add a missing space.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Fixes: d6006672788ec0f0290d35c76ceb9672476d1ea8
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
2020-01-27 17:36:05 +01:00
Peter Krempa
d9dfc1f7de qemu: checkpoint: Extract calculation of bitmap merging for checkpoint deletion
This will allow some testing before refactoring.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2020-01-27 15:28:49 +01:00
Peter Krempa
6796194a28 qemu: checkpoint: Introduce helper to find checkpoint disk definition in parents
The algorithm is used in two places to find the parent checkpoint object
which contains given disk and then uses data from the disk. Additionally
the code is written in a very non-obvious way. Factor out the lookup of
the disk into a function which also simplifies the callers.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2020-01-27 15:28:49 +01:00
Peter Krempa
180b3422e9 qemu: domain: Remove unused qemuDomainDiskNodeFormatLookup
The function has no users now and there's no need for it as the common
pattern is to look up the whole disk object anyways.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2020-01-27 15:28:49 +01:00
Peter Krempa
f19248a139 qemu: checkpoint: tolerate missing disks on checkpoint deletion
If a disk is unplugged and then the user tries to delete a checkpoint
the code would try to use NULL node name as it was not checked.

Fix this by fetching the whole disk definition object and verifying it
was found.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2020-01-27 15:28:49 +01:00
Peter Krempa
7973f7d792 qemu: checkpoint: Use disk definition directly when creating checkpoint
Lookup the whole disk definition rather than just the node name.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2020-01-27 15:28:49 +01:00
Peter Krempa
f3e0a45a00 qemu: checkpoint: rename disk->chkdisk in qemuCheckpointAddActions
Upcoming patches will also use the domain disk definition. Rename disk
to chkdisk for clarity.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2020-01-27 15:28:49 +01:00
Peter Krempa
a303e8ea47 qemu: checkpoint: rename disk->chkdisk in qemuCheckpointDiscardBitmaps
Upcoming patches will also use the domain disk definition. Rename disk
to chkdisk for clarity.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2020-01-27 15:28:49 +01:00
Peter Krempa
44e1b85717 qemu: checkpoint: split out checkpoint deletion bitmaps
qemuCheckpointDiscard is a massive function that can be separated into
smaller bits. Extract the part that actually modifies the disk from the
metadata handling.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2020-01-27 15:28:49 +01:00
Peter Krempa
606dc66b09 qemu: checkpoint: Store whether deleted checkpoint is current in a variable
Avoid two computations by using a boolean.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2020-01-27 15:28:49 +01:00
Peter Krempa
60b580b949 qemu: capabilities: Add accessor to qemu caps machine types presence
Test code will need to know whether the virQEMUCaps object contains any
machine types already. Add a helper and expose it via 'qemu_capspriv.h'.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2020-01-27 14:55:03 +01:00
Peter Krempa
3b8feb4793 qemu: capabilities: Replace aliased machine type by copy of the canonical machine
The previous approac of just purging the alias combined with the fact
that we filled in fake machine types in the test data meant that if a
test case used an alias machine type such as 'pc' or 'q35' it would not
properly resolve to the actual data returned by qemu.

This started to be a problem since the CPU driver now looks at the
default CPU reported with the machine type.

This patch replaces the original approach of just removing the alias by
replacing it with a copy of the machine type data which the type would
alias to. This means that we are using the real data while we don't
modify the test output after every qemu upgrade.

Additionally this change will allow us to drop adding the fake machine
types later.

The test fallout is from actually excercising the CPU driver with
actual data.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2020-01-27 14:55:03 +01:00
Peter Krempa
bb61230992 qemu: capabilities: Extract code from virQEMUCapsStripMachineAliases
Separate out the internals as they will become more complex soon.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2020-01-27 14:55:03 +01:00
Peter Krempa
0b9d1a8073 qemu: domain: Validate that machine type is supported by qemu
Every supported qemu is able to return the list of machine types it
supports so we can start validating it against that list. The advantage
is a better error message, and the change will also prevent having stale
test data.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2020-01-27 14:55:03 +01:00
Daniel P. Berrangé
82dd011dbb qemu: fix linking virt-qemu-run on some distros
Debian/Ubuntu linkers are more strict that other distros requiring glib
to be linked explicitly.

macOS needs -export-dynamic instead of -Wl,--export-dynamic

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2020-01-27 13:44:56 +00:00
Daniel P. Berrangé
9a5bafd329 bhyve: add 'root' parameter to driver initializer
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2020-01-27 13:44:56 +00:00
Peter Krempa
b168fa88b8 qemu: snapshot: Prevent too-nested domain XML when doing inactive snapshot
Similarly to 510d154a0b41aa70aadabc0918d16dee22882394 we need to prevent
doing too deeply nested backing chains and reject them with a sane error
message.

Add a loop to go through the snapshots prior to attempting actually
creating them to prevent some possible inconsistent scenarios.

We don't need to do it when reusing backing chains as we'll be
re-detecting the backing chain in that case anyways.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2020-01-27 14:02:01 +01:00
Peter Krempa
8e9e73a984 qemu: snapshot: Always rewrite backingStore data when reusing existing images
Don't adopt the backing store data when reusing images provided by the
user. This will force a backing chain re-probe as users might have
passed in something unexpected in the overlay where our view of the
backing chain would not correspond.

This is done only for inactive snapshots as there we have way less
verification.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2020-01-27 14:02:01 +01:00
Daniel P. Berrangé
d600667278 qemu: introduce a new "virt-qemu-run" program
The previous "QEMU shim" proof of concept was taking an approach of only
caring about initial spawning of the QEMU process. It was then
registered with the libvirtd daemon who took over management of it. The
intent was that later libvirtd would be refactored so that the shim
retained control over the QEMU monitor and libvirt just forwarded APIs
to each shim as needed. This forwarding of APIs would require quite alot
of significant refactoring of libvirtd to achieve.

This impl thus takes a quite different approach, explicitly deciding to
keep the VMs completely separate from those seen & managed by libvirtd.
Instead it uses the new "qemu:///embed" URI scheme to embed the entire
QEMU driver in the shim, running with a custom root directory.

Once the driver is initialization, the shim starts a VM and then waits
to shutdown automatically when QEMU shuts down, or should kill QEMU if
it is terminated itself. This ought to use the AUTO_DESTROY feature but
that is not yet available in embedded mode, so we rely on installing a
few signal handlers to gracefully kill QEMU. This isn't reliable if
we crash of course, but you can restart with the same root dir.

Note this program does not expose any way to manage the QEMU process,
since there's no RPC interface enabled. It merely starts the VM and
cleans up when the guest shuts down at the end. This program is
installed to /usr/bin/virt-qemu-run enabling direct use by end users.
Most use cases will probably want to integrate the concept directly
into their respective application codebases. This standalone binary
serves as a nice demo though, and also provides a way to measure
performance of the startup process quite simply.

Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2020-01-27 11:05:02 +00:00
Daniel P. Berrangé
3e9076e777 secrets: add support for running secret driver in embedded mode
This enables support for running the secret driver embedded to the
calling application process using a URI:

   secret:///embed?root=/some/path

When using the embedded mode with a root=/var/tmp/embed, the
driver will use the following paths:

       configDir: /var/tmp/embed/etc/secrets
        stateDir: /var/tmp/embed/run/secrets

These are identical whether the embedded driver is privileged
or unprivileged.

This compares with the system instance which uses

       configDir: /etc/libvirt/secrets
        stateDir: /var/lib/libvirt/secrets

When an embedded instance of the secret driver is open, any other
embedded drivers will automatically use the embedded secret driver.

Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2020-01-27 11:04:29 +00:00
Daniel P. Berrangé
068efae5b1 qemu: add support for running QEMU driver in embedded mode
This enables support for running QEMU embedded to the calling
application process using a URI:

   qemu:///embed?root=/some/path

Note that it is important to keep the path reasonably short to
avoid risk of hitting the limit on UNIX socket path names
which is 108 characters.

When using the embedded mode with a root=/var/tmp/embed, the
driver will use the following paths:

                logDir: /var/tmp/embed/log/qemu
           swtpmLogDir: /var/tmp/embed/log/swtpm
         configBaseDir: /var/tmp/embed/etc/qemu
              stateDir: /var/tmp/embed/run/qemu
         swtpmStateDir: /var/tmp/embed/run/swtpm
              cacheDir: /var/tmp/embed/cache/qemu
                libDir: /var/tmp/embed/lib/qemu
       swtpmStorageDir: /var/tmp/embed/lib/swtpm
 defaultTLSx509certdir: /var/tmp/embed/etc/pki/qemu

These are identical whether the embedded driver is privileged
or unprivileged.

This compares with the system instance which uses

                logDir: /var/log/libvirt/qemu
           swtpmLogDir: /var/log/swtpm/libvirt/qemu
         configBaseDir: /etc/libvirt/qemu
              stateDir: /run/libvirt/qemu
         swtpmStateDir: /run/libvirt/qemu/swtpm
              cacheDir: /var/cache/libvirt/qemu
                libDir: /var/lib/libvirt/qemu
       swtpmStorageDir: /var/lib/libvirt/swtpm
 defaultTLSx509certdir: /etc/pki/qemu

At this time all features present in the QEMU driver are available when
running in embedded mode, availability matching whether the embedded
driver is privileged or unprivileged.

Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2020-01-27 11:04:03 +00:00
Daniel P. Berrangé
88446e07b2 libvirt: support an "embed" URI path selector for opening drivers
The driver URI scheme:

  "$drivername:///embed?root=/some/path"

enables a new way to use the drivers by embedding them directly in the
calling process. To use this the process must have a thread running the
libvirt event loop. This URI will then cause libvirt to dynamically load
the driver module and call its global initialization function. This
syntax is applicable to any driver, but only those will have been
modified to support a custom root directory and embed URI path will
successfully open.

The application can now make normal libvirt API calls which are all
serviced in-process with no RPC layer involved.

It is required to specify an explicit root directory, and locks will be
acquired on this directory to avoid conflicting with another app that
might accidentally pick the same directory.

Use of '/' is not explicitly forbidden, but note that the file layout
used underneath the embedded driver root does not match the file
layout used by system/session mode drivers. So this cannot be used as
a backdoor to interact with, or fake, the system/session mode drivers.

Libvirt will create arbitrary files underneath this root directory. The
root directory can be kept untouched across connection open attempts if
the application needs persistence. The application is responsible for
purging everything underneath this root directory when finally no longer
required.

Even when a virt driver is used in embedded mode, it is still possible
for it to in turn use functionality that calls out to other secondary
drivers in libvirtd. For example an embedded instance of QEMU can open
the network, secret or storage drivers in the system libvirtd.

That said, the application would typically want to at least open an
embedded secret driver ("secret:///embed?root=/some/path"). Note that
multiple different embedded drivers can use the same root prefix and
co-operate just as they would inside a normal libvirtd daemon.

A key thing to note is that for this to work, the application that links
to libvirt *MUST* be built with -Wl,--export-dynamic to ensure that
symbols from libvirt.so are exported & thus available to the dynamically
loaded driver module. If libvirt.so itself was dynamically loaded then
RTLD_GLOBAL must be passed to dlopen().

Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2020-01-27 11:03:49 +00:00
Daniel P. Berrangé
207709a031 libvirt: pass a directory path into drivers for embedded usage
The intent here is to allow the virt drivers to be run directly embedded
in an arbitrary process without interfering with libvirtd. To achieve
this they need to store all their configuration & state in a separate
directory tree from the main system or session libvirtd instances.

This can be useful for doing testing of the virt drivers in "make check"
without interfering with the user's own libvirtd instances.

It can also be used for applications using KVM/QEMU as a piece of
infrastructure to build an service, rather than for general purpose
OS hosting. A long standing example is libguestfs, which would prefer
if its temporary VMs did show up in the main libvirtd VM list, because
this confuses apps such as OpenStack Nova. A more recent example would
be Kata which is using KVM as a technology to build containers.

Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Cole Robinson <crobinso@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2020-01-27 11:02:16 +00:00
Daniel P. Berrangé
fd2a9dda87 util: add helper API for getting URI parameters
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2020-01-27 11:02:03 +00:00
Jonathon Jongsma
dee2218bc8 qemu: explicitly disable virgl when requested
If a domain is configured to have an egl-headless display and a virtio
video device, virgl will be enabled automatically within the guest, even
if the video device is configured with accel3d='no'.

In this case we should explicitly pass 'virgl=off' to qemu.

See https://bugzilla.redhat.com/show_bug.cgi?id=1791236 for more
information.

Signed-off-by: Jonathon Jongsma <jjongsma@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2020-01-25 07:51:08 +01:00
Han Han
bd51f89c30 qemu: Implement builtin rng backend
Since v4.2-rc0, QEMU introduced a builtin rng backend that uses
getrandom() syscall to generate random. Add it to libvirt with the
backend model 'builtin'.

https://bugzilla.redhat.com/show_bug.cgi?id=1785091

Signed-off-by: Han Han <hhan@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2020-01-24 17:03:35 +01:00
Han Han
6a6d00e168 conf: Add rng backend model builtin
The 'builtin' rng backend model can be used as following:
  <rng model='virtio'>
    <backend model='builtin'/>
  </rng>

Signed-off-by: Han Han <hhan@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2020-01-24 17:03:32 +01:00
Han Han
1bd17918b6 util: Do not assume comma after object id
For qemu object like rng-builtin, there are no properties after id
property. We should always set comma after object id. Otherwise it will
cause trailing comma on object:
    -object rng-builtin,id=ID,

Signed-off-by: Han Han <hhan@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2020-01-24 17:03:29 +01:00
Han Han
9378713f56 qemu_capabilities: Introduce QEMU_CAPS_OBJECT_RNG_BUILTIN
It is used to check if qemu is capable of rng-builtin object.

This object is added since qemu-4.2.0-rc0, commit 6c4e9d48.

Signed-off-by: Han Han <hhan@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2020-01-24 17:03:21 +01:00
Michal Privoznik
c76009313f qemu_capabilities: Rework domain caps cache
Since v5.6.0-48-g270583ed98 we try to cache domain capabilities,
i.e. store filled virDomainCaps in a hash table in virQEMUCaps
for future use. However, there's a race condition in the way it's
implemented. We use virQEMUCapsGetDomainCapsCache() to obtain the
pointer to the hash table, then we search the hash table for
cached data and if none is found the domcaps is constructed and
put into the table. Problem is that this is all done without any
locking, so if there are two threads trying to do the same, one
will succeed and the other will fail inserting the data into the
table.

Also, the API looks a bit fishy - obtaining pointer to the hash
table is dangerous.

The solution is to use a mutex that guards the whole operation
with the hash table. Then, the API can be changes to return
virDomainCapsPtr directly.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1791790

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
2020-01-24 14:48:44 +01:00
Michal Privoznik
cc361a34c5 qemu_conf: Avoid dereferencing NULL in virQEMUDriverGetHost{NUMACaps,CPU}
When fixing [1] I've ran attached reproducer and had it spawn
1024 threads and query capabilities XML in each one of them. This
lead libvirtd to hit the RLIMIT_NOFILE limit which was kind of
expected. What wasn't expected was a subsequent segfault. It
happened because virCPUProbeHost failed and returned NULL. We've
taken the NULL and passed it to virCapabilitiesHostNUMARef()
which dereferenced it. Code inspection showed the same flas in
virQEMUDriverGetHostNUMACaps(), so I'm fixing both places.

1: https://bugzilla.redhat.com/show_bug.cgi?id=1791790

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
2020-01-24 14:48:44 +01:00
Michal Privoznik
609acf1f5d cpu.c: Check properly for virCapabilitiesGetNodeInfo() retval
The virCapabilitiesGetNodeInfo() function has the usual return
value semantics for integeres: a negative value means an error,
zero or a positive value means success. However, the function
call done in virCPUProbeHost() doesn't check for the return value
accordingly.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
2020-01-24 14:48:44 +01:00
Peter Krempa
29d43bf96a qemu: monitor: Improve error message when QEMU reply is too large
Don't use ERANGE as it doesn't make much sense in the error message.
Also point out that the reply from qemu was too large which is not
obvious from the original error:

 error: No complete monitor response found in 10485760 bytes: Numerical result out of range

The new message will read:

 error: internal error: QEMU monitor reply exceeds buffer size (10485760 bytes)

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Jiri Denemark <jdenemar@redhat.com>
2020-01-24 13:47:45 +01:00
Peter Krempa
f4e7c792d5 qemu: block: Don't skip creation of 'luks' formatted images
libvirt treats 'luks' images as raw+encryption. The logic in
qemuBlockStorageSourceCreateFormat skipped the creation if the requested
image was raw but didn't take into account the encryption.

This manifested itself e.g. when attempting to do a virsh blockcopy with
the following XML:

    <disk type='file' device='disk'>
      <driver name='qemu' type='raw'/>
      <source file='/tmp/enccpy'>
        <encryption format='luks'>
          <secret type='passphrase' uuid='0a81f5b2-8403-7b23-c8d6-21ccc2f80d6f'/>
        </encryption>
      </source>
    </disk>

Where qemu would report the following error:

 unable to execute QEMU command 'blockdev-add': Volume is not in LUKS format

rather than actually formatting the image first.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2020-01-24 13:46:46 +01:00
Peter Krempa
ae60e05817 util: hash: Improve debugability of "Duplicate key" error message
If we get a user reporting this error message being shown it's pretty
useless in terms of actually debugging it since we don't know which hash
and which key are actually subject to the error.

This patch adds a new hash table callback which formats the
user-readable version of the hash key and reports it in the new message
which will look like:

"Duplicate hash table key 'blah'"

That way we will at least have an anchor point where to start the
search.

There are two special implementations of keys which are numeric so we
add specific printer functions for them.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2020-01-24 13:45:38 +01:00
Peter Krempa
0c3792a155 qemu: backup: Implement support for backup disk bitmap name configuration
Use the user-configured name of the bitmap when merging the appropriate
bitmaps for an incremental backup so that the user can see it as
configured. Additionally expose the default bitmap name if nothing is
configured.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
2020-01-24 13:40:53 +01:00
Peter Krempa
bce4ac55f8 qemu: backup: Implement support for backup disk export name configuration
Pass the exportname as configured when exporting the image via NBD and
fill it with the default if it's not configured.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2020-01-24 13:40:48 +01:00
Peter Krempa
12ccd8d4db conf: backup: Allow configuration of names exported via NBD
If users wish to use different name for exported disks or bitmaps
the new fields allow to do so. Additionally they also document the
current settings.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2020-01-24 13:40:48 +01:00
Peter Krempa
69908db0f6 qemu: Fix value of 'device' argument for block-commit
When using blockdev configurations the 'device' argument of
'blockdev-commit' must correspond to the topmost node in the block node
graph. Libvirt didn't do this properly in case when 'copy_on_read'
option was enabled on the disk.

Use qemuDomainDiskGetTopNodename to fix it when calling block-commit.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2020-01-24 13:40:36 +01:00
Peter Krempa
e3137539a9 qemu: Fix value of 'device' argument for blockdev-mirror
When using blockdev configurations the 'device' argument of
'blockdev-mirror' must correspond to the topmost node in the block node
graph. Libvirt didn't do this properly in case when 'copy_on_read'
option was enabled on the disk.

Use qemuDomainDiskGetTopNodename to fix it for the blockdev-mirror calls
in qemuDomainBlockCopy and the non-shared-storage migration.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2020-01-24 13:40:36 +01:00
Peter Krempa
0b0f389335 qemu: domain: Extract code to determine topmost nodename to qemuDomainDiskGetTopNodename
There are more places which require getting the topmost nodename to be
passed to qemu. Separate it out into a new function.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2020-01-24 13:40:36 +01:00
Peter Krempa
623366d130 qemu: blockcopy: Actually unplug unused images when mirror job fails to start
If a mirror job fails to start in -blockdev mode we'd not unplug the
backing files we added first because the code on the error path checked
the wrong value. 'rc' is used as status of the code which added the
images, but the state of the 'block(dev)-mirror' call is stored in 'ret'
at that point.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2020-01-24 13:40:36 +01:00
Daniel P. Berrangé
6d786f95a3 qemu: fixing auto-detecting binary in domain capabilities
The virConnectGetDomainCapabilities API accepts either a binary path
to the emulator, or desired guest arch. If guest arch is not given,
then the host arch is assumed.

In the case where the binary is not given, the code tried to find the
emulator binary in the existing list of cached emulator capabilities.
This is not valid since we switched to lazy population of the cache in:

  commit 3dd91af01f30c5bda6328454ef49f3afece755d6
  Author: Daniel P. Berrangé <berrange@redhat.com>
  Date:   Mon Dec 2 13:04:26 2019 +0000

    qemu: stop creating capabilities at driver startup

As a result of this change, if there are no persistent guests defined
using the requested guest architecture, virConnectGetDomainCapabilities
will fail to find an emulator binary.

The solution is to stop relying on the cached capabilities to find the
binary and instead use the same logic we use to pick default a binary
per arch when populating capabilities.

Tested-by: Boris Fiuczynski <fiuczy@linux.ibm.com>
Tested-by: Richard W.M. Jones <rjones@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2020-01-23 16:38:59 +00:00