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>
Some of objects we manage can be autostarted on libvirtd startup
(e.g. domains, network, storage pools). The idea was that when
the host is started up these objects are started too without need
of user intervention. However, with the latest daemon split and
switch to socket activated, short lived daemons (we put --timeout
120 onto each daemon's command line) this doesn't do what we want
it to. The problem is not new though, we already had the session
daemon come and go and we circumvented this problem by
documenting it (see v4.10.0-92-g61b4e8aaf1). But now that we meet
the same problem at all fronts it's time to deal with it.
The solution implemented in this commit is to have a file (one
per each driver) that:
1) if doesn't exist, is created and autostart is allowed for
given driver,
2) if it does exist, then autostart is suppressed for given
driver.
All the files live in a location that doesn't survive host
reboots (/var/run/ for instance) and thus the file is
automatically not there on fresh host boot.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
The code to validate the URI path is repeated across several
files. This patch creates a common validation code to be
used across all of them.
Reviewed-by: Cole Robinson <crobinso@redhat.com>
Suggested-by: Cole Robinson <crobinso@redhat.com>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Historically URIs handled by the remote driver will always connect to
the libvirtd UNIX socket. There will now be one daemon per driver, and
each of these has its own UNIX sockets to connect to.
It will still be possible to run the traditional monolithic libvirtd
though, which will have the original UNIX socket path.
In addition there is a virproxyd daemon that doesn't run any drivers,
but provides proxying for clients accessing libvirt over IP sockets, or
tunnelling to the legacy libvirtd UNIX socket path.
Finally when running inside a daemon, the remote driver must not reject
connections unconditionally. For example, the QEMU driver needs to be
able to connect to the network driver. The remote driver must thus be
willing to handle connections even when inside the daemon, provided no
local driver is registered.
This refactoring enables the remote driver to be able to connect to the
per-driver daemons. The URI parameter "mode" accepts the values "auto",
"direct" and "legacy" to control which daemons are connected to.
The client side libvirt.conf config file also supports a "remote_mode"
setting which is used if the URI parameter is not set.
If neither the config file or URI parameter set a mode, then "auto"
is used, whereby the client looks to see which sockets actually exist
right now.
The remote driver will only ever spawn the per-driver daemons, or
the legacy libvirtd. It won't ever try to spawn virtproxyd, as
that is only there for IP based connectivity, or for access from
legacy remote clients.
If connecting to a remote host over any kind of ssh tunnel, for now we
must assume only the legacy socket exists. A future patch will introduce
a netcat replacement that is tailored for libvirt to make remote
tunnelling easier.
The configure arg '--with-remote-default-mode=legacy|direct' allows
packagers to set a default at build time. If not given, it will default
to legacy mode.
Eventually the default will switch to direct mode. Distros can choose
to do the switch earlier if desired. The main blocker is testing and
suitable SELinux/AppArmor policies.
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Require that all headers are guarded by a symbol named
LIBVIRT_$FILENAME
where $FILENAME is the uppercased filename, with all characters
outside a-z changed into '_'.
Note we do not use a leading __ because that is technically a
namespace reserved for the toolchain.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
This new flag will be set when a driver needs a remote URL in order to
work, as ESX, HyperV and Phyp.
Signed-off-by: Marcos Paulo de Souza <marcos.souza.org@gmail.com>
The driver.{c,h} files are primarily targetted at loading hypervisor
drivers and some helper functions in that area. It also, however,
contains a generically useful function for loading extension modules
that is called by the storage driver. Split that functionality off
into a new virmodule.{c,h} file to isolate it.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Currently the driver module loading code does not report an error if the
driver module is physically missing on disk. This is useful for distro
packaging optional pieces. When the daemons are split up into one daemon
per driver, we will expect module loading to always succeed. If a driver
is not desired, the entire daemon should not be installed.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Now that we've activated two hacks to prevent unloading of modules,
there is no point passing back a pointer to the loaded library handle.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Declare what URI schemes a driver supports in its virConnectDriver
struct. This allows us to skip trying to open the driver entirely
if the URI scheme doesn't match.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Add a localOnly flag to the virConnectDriver struct which allows a
driver to indicate whether it is local-only, or permits remote
connections. Stateful drivers running inside libvirtd are generally
local only. This allows us to remote the check for uri->server != NULL
from most drivers.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
When the test suite is running, we don't want to be triggering the
startup of daemons for the secondary drivers. Thus we must provide a way
to set a custom connection for the secondary drivers, to override the
default logic which opens a new connection.
This will also be useful for code where we have a whole set of separate
functions calls all needing the secret driver. Currently the connection
to the secret driver is opened & closed many times in quick
succession. This will allow us to pre-open a connection temporarily,
improving the performance of startup.
Reviewed-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Various parts of libvirt will want to open connections to secondary
drivers. The right URI to use will depend on the context, so rather than
duplicating that logic in various places, use some helper APIs. This
will also make it easier for us to later pre-open/cache connections to
avoid repeated opening & closing the same connectiong during autostart.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Right-aligning backslashes when defining macros or using complex
commands in Makefiles looks cute, but as soon as any changes is
required to the code you end up with either distractingly broken
alignment or unnecessarily big diffs where most of the changes
are just pushing all backslashes a few characters to one side.
Generated using
$ git grep -El '[[:blank:]][[:blank:]]\\$' | \
grep -E '*\.([chx]|am|mk)$$' | \
while read f; do \
sed -Ei 's/[[:blank:]]*[[:blank:]]\\$/ \\/g' "$f"; \
done
Signed-off-by: Andrea Bolognani <abologna@redhat.com>
Pass the registration function name to virDriverLoadModule so that we
can later call specific functions if necessary (e.g. for testing
purposes). This gets rid of the rather ugly automatic name generator and
unifies the code to load/initialize the modules.
It's also clear which registration function gets called.
For stateless, client side drivers, it is never correct to
probe for secondary drivers. It is only ever appropriate to
use the secondary driver that is associated with the
hypervisor in question. As a result the ESX & HyperV drivers
have both been forced to do hacks where they register no-op
drivers for the ones they don't implement.
For stateful, server side drivers, we always just want to
use the same built-in shared driver. The exception is
virtualbox which is really a stateless driver and so wants
to use its own server side secondary drivers. To deal with
this virtualbox has to be built as 3 separate loadable
modules to allow registration to work in the right order.
This can all be simplified by introducing a new struct
recording the precise set of secondary drivers each
hypervisor driver wants
struct _virConnectDriver {
virHypervisorDriverPtr hypervisorDriver;
virInterfaceDriverPtr interfaceDriver;
virNetworkDriverPtr networkDriver;
virNodeDeviceDriverPtr nodeDeviceDriver;
virNWFilterDriverPtr nwfilterDriver;
virSecretDriverPtr secretDriver;
virStorageDriverPtr storageDriver;
};
Instead of registering the hypervisor driver, we now
just register a virConnectDriver instead. This allows
us to remove all probing of secondary drivers. Once we
have chosen the primary driver, we immediately know the
correct secondary drivers to use.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
A bunch of code is wrapped in #if WITH_LIBVIRTD in order to
enable the virStateDriver to be disabled when libvirtd is not
built. Disabling this code doesn't have any real functional
benefit beyond removing 1 pointer from the virConnectPtr struct,
while having a cost of many more conditionals.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
With the large number of APIs in libvirt the driver.h file,
it is easy to get lost looking for things. Split each driver
into a separate header file based on the functional driver
groups.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
To prepare for introducing a single global driver, rename the
virDriver struct to virHypervisorDriver and the registration
API to virRegisterHypervisorDriver()
A long time ago in a galaxy far, far away it has been decided
that libvirt will manage not only domains but host as well. And
with my latest work on qemu driver supporting huge pages, we miss
the cherry on top: an API to allocate huge pages on the run.
Currently users are forced to log into the host and adjust the
huge pages pool themselves. However, with this API the problem
is gone - they can both size up and size down the pool.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Clean up all _virDomainMemoryStat.
Signed-off-by: James <james.wangyufei@huawei.com>
Signed-off-by: Wang Rui <moon.wangrui@huawei.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Clean up all _virDomainBlockStats.
Signed-off-by: James <james.wangyufei@huawei.com>
Signed-off-by: Wang Rui <moon.wangrui@huawei.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Clean up all _virDomainInterfaceStats.
Signed-off-by: Wang Yufei <james.wangyufei@huawei.com>
Signed-off-by: Wang Rui <moon.wangrui@huawei.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Let's fix this before we bake in a painful API. Since we know
that we have exactly one non-negative fd on success, we might
as well return the fd directly instead of forcing the user to
pass in a pointer. Furthermore, I found some memory and fd
leaks while reviewing the code - the idea is that on success,
libvirtd will have handed two fds in two different directions:
one to qemu, and one to the RPC client.
* include/libvirt/libvirt.h.in (virDomainOpenGraphicsFD): Drop
unneeded parameter.
* src/driver.h (virDrvDomainOpenGraphicsFD): Likewise.
* src/libvirt.c (virDomainOpenGraphicsFD): Adjust interface to
return fd directly.
* daemon/remote.c (remoteDispatchDomainOpenGraphicsFd): Adjust
semantics.
* src/qemu/qemu_driver.c (qemuDomainOpenGraphicsFD): Likewise,
and plug fd leak.
* src/remote/remote_driver.c (remoteDomainOpenGraphicsFD):
Likewise, and plug memory and fd leak.
Signed-off-by: Eric Blake <eblake@redhat.com>
This commit (finally) adds the virDomainBlockCopy API, with the
intent that it will provide more power to the existing 'virsh
blockcopy' command.
'virsh blockcopy' was first added in Apr 2012 (v0.9.12), which
corresponds to the upstream qemu 1.2 timeframe. It was done as
a hack on top of the existing virDomainBlockRebase() API call,
for two reasons: 1) it was targetting a feature that landed first
in downstream RHEL qemu, but had not stabilized in upstream qemu
at the time (and indeed, 'drive-mirror' only landed upstream in
qemu 1.3 with slight differences to the first RHEL attempt,
and later gained further parameters like granularity and buf-size
that are also worth exposing), and 2) extending an existing API
allowed it to be backported without worrying about bumping .so
versions. A virDomainBlockCopy() API was proposed at that time
[1], but we decided not to accept it into libvirt until after
upstream qemu stabilized, and it ended up getting scrapped.
Whether or not RHEL should have attempted adding a new feature
without getting it upstream first is a debate that can be held
another day; but enough time has now elapsed that we are ready to
do the interface cleanly.
[1] https://www.redhat.com/archives/libvir-list/2012-April/msg00768.html
Delaying the creation of a clean API until now has also had a
benefit: we've only recently learned of a few shortcomings in the
original design: 1) it is unable to target a network destination
(such as a gluster volume) because it hard-coded the assumption
that the destination is a local file name. Because of all the
refactoring we've done to add virStorageSourcePtr, we are in a
better position to declare an API that parses XML describing a
host storage source as the copy destination, which was not
possible had we implemented virDomainBlockCopy as it had been
originally envisioned (although a network target will have to wait
until a later libvirt release compared to the API addition to
actually be implemented). 2) the design of using MiB/sec as the
bandwidth throttle is rather coarse; qemu is actually tuned to
bytes/second, and libvirt is preventing access to that level of
detail. A later patch will add flags to existing block job API
that can request bytes/second instead of back-compat MiB/s, but as
this is a new API, we can get it right to begin with.
At least I had the foresight to create 'virsh blockcopy' as a
separate command at the UI level (commit 1f06c00) rather than
leaking the underlying API overload of virDomainBlockRebase onto
shell users.
A further note on the bandwidth option: virTypedParameters
intentionally lacks unsigned long (since variable-width
interaction between mixed 32- vs. 64-bit client/server setups is
nasty), but we have to deal with the fact that we are interacting
with existing older code that mistakenly chose unsigned long
bandwidth at a point before we decided to prohibit it in all new
API. The typed parameter is therefore unsigned long long, but
the implementation (in a later patch) will have to do overflow
detection on 32-bit platforms, as well as capping the value to
match the LLONG_MAX>>20 cap of the existing MiB/s interfaces.
* include/libvirt/libvirt.h.in (virDomainBlockCopy): New API.
(virDomainBlockJobType, virConnectDomainEventBlockJobStatus):
Update related documentation.
* src/libvirt.c (virDomainBlockCopy): Implement it.
* src/libvirt_public.syms (LIBVIRT_1.2.8): Export it.
* src/driver.h (_virDriver): New driver callback.
Signed-off-by: Eric Blake <eblake@redhat.com>
The motivation for this API is that management layers that use libvirt
usually poll for statistics using various split up APIs we currently
provide. To get all the necessary stuff, the app needs to issue a lot of
calls and aggregate the results.
The APIs I'm introducing here:
1) Returns data in a format that we can expand in the future and is
(pseudo) hierarchical. The data is returned as typed parameters where
the fields are constructed as dot-separated strings containing names and
other stuff in a list of typed params.
2) Stats for multiple (all) domains can be queried at once and are
returned in one call. This will decrease the overhead necessary to issue
multiple calls per domain multiplied by the count of domains.
3) Selectable (bit mask) fields in the returned format. This will allow
to retrieve only specific stats according to the app's need.
The stats groups will be enabled using a bit field @stats passed as the
function argument. A few sample stats groups that this API will support:
VIR_DOMAIN_STATS_STATE
VIR_DOMAIN_STATS_CPU
VIR_DOMAIN_STATS_BLOCK
VIR_DOMAIN_STATS_INTERFACE
(Note that this is only an example, the initial implementation supports
only VIR_DOMAIN_STATS_STATE while others will be added later.)
the returned typed params will use the following scheme
state.state = VIR_DOMAIN_RUNNING
state.reason = VIR_DOMAIN_RUNNING_BOOTED (the actual values according to
the enum)
cpu.count = 8
cpu.0.state = running
cpu.0.time = 1234
On some places in the libvirt code we have:
f(a,z)
instead of
f(a, z)
This trivial patch fixes couple of such occurrences.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Instead of maintaining two very similar APIs, add the "@mac" parameter
to virNetworkGetDHCPLeases and kill virNetworkGetDHCPLeasesForMAC. Both
of those functions would return data the same way, so making @mac an
optional filter simplifies a lot of stuff.
Introduce 3 new APIs, virNetworkGetDHCPLeases, virNetworkGetDHCPLeasesForMAC
and virNetworkDHCPLeaseFree.
* virNetworkGetDHCPLeases: returns the dhcp leases information for a given
virtual network.
For DHCPv4, the information returned:
- Network Interface Name
- Expiry Time
- MAC address
- IAID (NULL)
- IPv4 address (with type and prefix)
- Hostname (can be NULL)
- Client ID (can be NULL)
For DHCPv6, the information returned:
- Network Interface Name
- Expiry Time
- MAC address
- IAID (can be NULL, only in rare cases)
- IPv6 address (with type and prefix)
- Hostname (can be NULL)
- Client DUID
Note: @mac, @iaid, @ipaddr, @clientid are in ASCII form, not raw bytes.
Note: @expirytime can 0, in case the lease is for infinite time.
* virNetworkGetDHCPLeasesForMAC: returns the dhcp leases information for a
given virtual network and specified MAC Address.
* virNetworkDHCPLeaseFree: allows the upper layer application to free the
network interface object conveniently.
There is no support for flags, so user is expected to pass 0 for
both the APIs.
include/libvirt/libvirt.h.in:
* Define virNetworkGetDHCPLeases
* Define virNetworkGetDHCPLeasesForMAC
* Define virNetworkDHCPLeaseFree
src/driver.h:
* Define networkGetDHCPLeases
* Define networkGetDHCPLeasesForMAC
src/libvirt.c:
* Implement virNetworkGetDHCPLeases
* Implement virNetworkGetDHCPLeasesForMAC
* Implement virNetworkDHCPLeaseFree
src/libvirt_public.syms:
* Export the new symbols
The aim of the API is to get information on number of free pages
on the system. The API behaves similar to the
virNodeGetCellsFreeMemory(). User passes starting NUMA cell, the
count of nodes that he's interested in, pages sizes (yes,
multiple sizes can be queried at once) and the counts are
returned in an array.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
These APIs allow users to get or set time in a domain, which may come
handy if the domain has been resumed just recently and NTP is not
configured or hasn't kicked in yet and the guest is running
something time critical. In addition, NTP may refuse to re-set the clock
if the skew is too big.
In addition, new ACL attribute is introduced 'set_time'.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
These will freeze and thaw filesystems within guest specified by
@mountpoints parameters. The parameters can be NULL and 0, then all
mounted filesystems are frozen or thawed. @flags parameter, which are
currently not used, is for future extensions.
Signed-off-by: Tomoki Sekiyama <tomoki.sekiyama@hds.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
--memory-only option is introduced without compression supported. Now qemu
has support for dumping domain's memory in kdump-compressed format. This
patch adds a new virDomainCoreDumpWithFormat API, so that the format in
which qemu dumps domain's memory can be specified.
Signed-off-by: Qiao Nuohan <qiaonuohan@cn.fujitsu.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Several times in the past, qemu has implemented a new event,
but libvirt has not yet caught up to reporting that event to
the user applications. While it is possible to track libvirt
logs to see that an unknown event was received and ignored,
it would be nicer to copy what 'virsh qemu-monitor-command'
does, and expose this information to the end developer as
one of our unsupported qemu-specific commands.
If you find yourself needing to use this API for more than
just development purposes, please ask on the libvirt list
for a supported counterpart event to be added in libvirt.so.
While the supported virConnectDomainEventRegisterAny() API
takes an id which determines the signature of the callback,
this version takes a string filter and always uses the same
signature. Furthermore, I chose to expose this as a new API
instead of trying to add a new eventID at the top level, in
part because the generic option lacks event name filtering,
and in part because the normal domain event namespace should
not be polluted by a qemu-only event. I also added a flags
argument; unused for now, but we might decide to use it to
allow a user to request event names by glob or regex instead
of literal match.
This API intentionally requires full write access (while
normal event registration is allowed on read-only clients);
this is in part due to the fact that it should only be used
by debugging situations, and in part because the design of
per-event filtering in later patches ended up allowing for
duplicate registrations that could potentially be abused to
exhaust server memory - requiring write privileges means
that such abuse will not serve as a denial of service attack
against users with higher privileges.
* include/libvirt/libvirt-qemu.h
(virConnectDomainQemuMonitorEventCallback)
(virConnectDomainQemuMonitorEventRegister)
(virConnectDomainQemuMonitorEventDeregister): New prototypes.
* src/libvirt-qemu.c (virConnectDomainQemuMonitorEventRegister)
(virConnectDomainQemuMonitorEventDeregister): New functions.
* src/libvirt_qemu.syms (LIBVIRT_QEMU_1.2.1): Export them.
* src/driver.h (virDrvConnectDomainQemuMonitorEventRegister)
(virDrvConnectDomainQemuMonitorEventDeregister): New callbacks.
Signed-off-by: Eric Blake <eblake@redhat.com>
At this point it has a limited functionality and is highly
experimental. Supported domain operations are:
* define
* start
* destroy
* dumpxml
* dominfo
It's only possible to have only one disk device and only one
network, which should be of type bridge.
The libvirt_internal.h header was included by the internal.h header.
This made it painful to add new stuff to the header file that would
require some more specific types. Remove inclusion by internal.h and add
it to appropriate places manually.
Define the public API for (de-)registering network events
and the callbacks for receiving lifecycle events. The lifecycle
event includes a 'detail' parameter to match the domain lifecycle
event data, but this is currently unused.
The network events related code goes into its own set of internal
files src/conf/network_event.[ch]
The new function virConnectGetCPUModelNames allows to retrieve the list
of CPU models known by the hypervisor for a specific architecture.
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
With container based virt, it is useful to be able to pass
pre-opened file descriptors to the container init process.
This allows for containers to be auto-activated from incoming
socket connections, passing the active socket into the container.
To do this, introduce a pair of new APIs, virDomainCreateXMLWithFiles
and virDomainCreateWithFiles, which accept an array of file
descriptors. For the LXC driver, UNIX file descriptor passing
will be used to send them to libvirtd, which will them pass
them down to libvirt_lxc, which will then pass them to the container
init process.
This will only be implemented for LXC right now, but the design
is generic enough it could work with other hypervisors, hence
I suggest adding this to libvirt.so, rather than libvirt-lxc.so
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
