The qemu driver accesses fields in the virDomainNetDef directly, but
with the advent of the virDomainActualNetDef, some pieces of
information may be found in a different place (the ActualNetDef) if
the network connection is of type='network' and that network is of
forward type='bridge|private|vepa|passthrough'. The previous patch
added functions to mask this difference from callers - they hide the
decision making process and just pick the value from the proper place.
This patch uses those functions in the qemu driver as a first step in
making qemu work with the new network types. At this point, the
virDomainActualNetDef is guaranteed always NULL, so the GetActualX()
function will return exactly what the def->X that's being replaced
would have returned (ie bisecting is not compromised).
There is one place (in qemu_driver.c) where the internal details of
the NetDef are directly manipulated by the code, so the GetActual
functions cannot be used there without extra additional code; that
file will be treated in a separate patch.
The virtPortProfile in the domain interface struct is now a separately
allocated object *pointed to by* (rather than contained in) the main
virDomainNetDef object. This is done to make it easier to figure out
when a virtualPortProfile has/hasn't been specified in a particular
config.
Otherwise, an ABI mismatch gives error messages attributing the target
xml string as current, and the current domain state as the new xml.
* src/qemu/qemu_migration.c (qemuMigrationBegin): Use correct
argument order.
Starting/ending jobs when closing the connection may reset any
error which was reported earlier in p2p migration. We must
save the original error before doing so. This means we can also
just call virConnectClose as normal, instead of virUnrefConnect
* src/qemu/qemu_migration.c: Preserve errors in p2p migration
Commit f548480b broke migration v3 on qemu, because the driver
passed flags on through to qemu_migration even though
qemu_migration wasn't using those flags.
* src/qemu/qemu_migration.h (QEMU_MIGRATION_FLAGS): New define.
* src/qemu/qemu_driver.c: Simplify all migration callbacks.
* src/qemu/qemu_migration.c (qemuMigrationConfirm): Fix regression.
Continuation of commit 313ac7fd, and enforce things with a syntax
check.
Technically, virNetServerClientCalculateHandleMode is not printing
a mode_t, but rather a collection of VIR_EVENT_HANDLE_* bits;
however, these bits are < 8, so there is no different in the
output, and that was the easiest way to silence the new syntax check.
* cfg.mk (sc_flags_debug): New syntax check.
(exclude_file_name_regexp--sc_flags_debug): Add exemptions.
* src/fdstream.c (virFDStreamOpenFileInternal): Print flags in
hex, mode_t in octal.
* src/libvirt-qemu.c (virDomainQemuMonitorCommand)
(virDomainQemuAttach): Likewise.
* src/locking/lock_driver_nop.c (virLockManagerNopInit): Likewise.
* src/locking/lock_driver_sanlock.c (virLockManagerSanlockInit):
Likewise.
* src/locking/lock_manager.c: Likewise.
* src/qemu/qemu_migration.c: Likewise.
* src/qemu/qemu_monitor.c: Likewise.
* src/rpc/virnetserverclient.c
(virNetServerClientCalculateHandleMode): Print mode with %o.
Most of the code in these two functions is supposed to be identical but
currently it isn't (which is natural since the code is duplicated).
Let's move common parts of these functions into qemuMigrationPrepareAny.
This also fixes qemuMigrationPrepareTunnel which didn't store received
lockState in the domain object.
Query commands are safe to be called during long running jobs (such as
migration). This patch makes them all work without the need to
special-case every single one of them.
The patch introduces new job.asyncCond condition and associated
job.asyncJob which are dedicated to asynchronous (from qemu monitor
point of view) jobs that can take arbitrarily long time to finish while
qemu monitor is still usable for other commands.
The existing job.active (and job.cond condition) is used all other
synchronous jobs (including the commands run during async job).
Locking schema is changed to use these two conditions. While asyncJob is
active, only allowed set of synchronous jobs is allowed (the set can be
different according to a particular asyncJob) so any method that
communicates to qemu monitor needs to check if it is allowed to be
executed during current asyncJob (if any). Once the check passes, the
method needs to normally acquire job.cond to ensure no other command is
running. Since domain object lock is released during that time, asyncJob
could have been started in the meantime so the method needs to recheck
the first condition. Then, normal jobs set job.active and asynchronous
jobs set job.asyncJob and optionally change the list of allowed job
groups.
Since asynchronous jobs only set job.asyncJob, other allowed commands
can still be run when domain object is unlocked (when communicating to
remote libvirtd or sleeping). To protect its own internal synchronous
commands, the asynchronous job needs to start a special nested job
before entering qemu monitor. The nested job doesn't check asyncJob, it
only acquires job.cond and sets job.active to block other jobs.
The LXC and UML drivers can both make use of auditing. Move
the qemu_audit.{c,h} files to src/conf/domain_audit.{c,h}
* src/conf/domain_audit.c: Rename from src/qemu/qemu_audit.c
* src/conf/domain_audit.h: Rename from src/qemu/qemu_audit.h
* src/Makefile.am: Remove qemu_audit.{c,h}, add domain_audit.{c,h}
* src/qemu/qemu_audit.h, src/qemu/qemu_cgroup.c,
src/qemu/qemu_command.c, src/qemu/qemu_driver.c,
src/qemu/qemu_hotplug.c, src/qemu/qemu_migration.c,
src/qemu/qemu_process.c: Update for changed audit API names
The drivers were accepting domain configs without checking if those
were actually meant for them. For example the LXC driver happily
accepts configs with type QEMU.
Add a check for the expected domain types to the virDomainDefParse*
functions.
If virDomainSaveConfig() failed, we will return NULL to source,
and the vm is still available to restart during confirm() step in
v3 protocol. So we should kill it off in qemuMigrationFinish().
In v2 protocol, we should not set vm to NULL, because we hold
a reference of vm and should unrefernce it.
Detected by Coverity. qemuDomainEventQueue requires a non-NULL
pointer; most callers silently drop the event if we encountered
and OOM situation trying to create the event.
* src/qemu/qemu_migration.c (qemuMigrationFinish): Check for OOM.
The virSecurityManagerSetFDLabel method is used to label
file descriptors associated with disk images. There will
shortly be a need to label other file descriptors in a
different way. So the current name is ambiguous. Rename
the method to virSecurityManagerSetImageFDLabel to clarify
its purpose
* src/libvirt_private.syms,
src/qemu/qemu_migration.c, src/qemu/qemu_process.c,
src/security/security_apparmor.c, src/security/security_dac.c,
src/security/security_driver.h, src/security/security_manager.c,
src/security/security_manager.h, src/security/security_selinux.c,
src/security/security_stack.c: s/FDLabel/ImageFDLabel/
The qemuMigrationPrepareDirect/PrepareTunnel methods accidentally
set the domain job to QEMU_JOB_MIGRATION_OUT when it should have
been QEMU_JOB_MIGRATION_IN. This didn't have any ill-effect, but
it is none-the-less wrong.
* src/qemu/qemu_migration.c: Fix job type
If an application is using libvirt + KVM as a piece of its
internal infrastructure to perform a specific task, it can
be desirable to guarentee the VM dies when the virConnectPtr
disconnects from libvirtd. This ensures the app can't leak
any VMs it was using. Adding VIR_DOMAIN_START_AUTOKILL as
a flag when starting guests enables this to be done.
* include/libvirt/libvirt.h.in: All VIR_DOMAIN_START_AUTOKILL
* src/qemu/qemu_driver.c: Support automatic killing of guests
upon connection close
* tools/virsh.c: Add --autokill flag to 'start' and 'create'
commands
Migration is a multi-step process
1. Begin(src)
2. Prepare(dst)
3. Perform(src)
4. Finish(dst)
5. Confirm(src)
At step 2, a QEMU process is lauched in the destination to
accept the incoming migration. Occasionally the process
that is controlling the migration workflow aborts, and fails
to call step 4, Finish. This leaves a QEMU process running
on the target (albeit with paused CPUs). Unfortunately because
step 2 actives a job on the QEMU process, it is unkillable by
normal means.
By registering the VM for autokill against the src virConnectPtr
in step 2, we can ensure that the guest is forcefully killed off
if the connection is closed without step 4 being invoked
* src/qemu/qemu_migration.c: Register autokill in PrepareDirect
and PrepareTunnel. Unregister autokill on successful run
of Finish
* src/qemu/qemu_process.c: Unregister autokill when stopping a
process
Sometimes it is useful to be able to automatically destroy a guest when
a connection is closed. For example, kill an incoming migration if
the client managing the migration dies. This introduces a map between
guest 'uuid' strings and virConnectPtr objects. When a connection is
closed, any associated guests are killed off.
* src/qemu/qemu_conf.h: Add autokill hash table to qemu driver
* src/qemu/qemu_process.c, src/qemu/qemu_process.h: Add APIs
for performing autokill of guests associated with a connection
* src/qemu/qemu_driver.c: Initialize autodestroy map
When peer-2-peer migration was invoked by a client supporting
v3, but where the target server only supported v2, we'd not
correctly shutdown the guest.
* src/qemu/qemu_migration.c: Ensure guest is shutdown in
v2 peer 2 peer migration
The v2 migration protocol doesn't use cookies, so we should not
be raising an error if the cookie parameters are NULL.
* src/qemu/qemu_migration.c: Don't raise error if cookie is NULL
In v3 migration, once migration is completed, the VM needs
to be left in a paused state until after Finish3 has been
executed on the target. Only then will the VM be killed
off. When using non-JSON QEMU monitor though, we don't
receive any 'STOP' event from QEMU, so we need to manually
set our state offline & thus release lock manager leases.
It doesn't hurt to run this on the JSON case too, just in
case the event gets lost somehow
* src/qemu/qemu_migration.c: Explicitly set VM state to
paused when migration completes
Some lock managers associate state with leases, allowing a process
to temporarily release its leases, and re-acquire them later, safe
in the knowledge that no other process has acquired + released the
leases in between.
This is already used between suspend/resume operations, and must
also be used across migration. This passes the lockstate in the
migration cookie. If the lock manager uses lockstate, then it
becomes compulsory to use the migration v3 protocol to get the
cookie support.
* src/qemu/qemu_driver.c: Validate that migration v2 protocol is
not used if lock manager needs state transfer
* src/qemu/qemu_migration.c: Transfer lock state in migration
cookie XML
Update the qemuDomainMigrateBegin method so that it accepts
an optional incoming XML document. This will be validated
for ABI compatibility against the current domain config,
and if this check passes, will be passed back out for use
by the qemuDomainMigratePrepare method on the target
* src/qemu/qemu_domain.c, src/qemu/qemu_domain.h,
src/qemu/qemu_migration.c: Allow custom XML to be passed
Originally most of libvirt domain-specific calls were blocking
during a migration.
A new mechanism to allow specific calls (blkstat/blkinfo) to be
executed in such condition has been implemented.
In the long term it'd be desirable to get a more general
solution to mark further APIs as migration safe, without needing
special case code.
* src/qemu/qemu_migration.c: add some additional job signal
flags for doing blkstat/blkinfo during a migration
* src/qemu/qemu_domain.c: add a condition variable that can be
used to efficiently wait for the migration code to clear the
signal flag
* src/qemu/qemu_driver.c: execute blkstat/blkinfo using the
job signal flags during migration
The current virDomainMigrateFinish3 method signature attempts to
distinguish two types of errors, by allowing return with ret== 0,
but ddomain == NULL, to indicate a failure to start the guest.
This is flawed, because when ret == 0, there is no way for the
virErrorPtr details to be sent back to the client.
Change the signature of virDomainMigrateFinish3 so it simply
returns a virDomainPtr, in the same way as virDomainMigrateFinish2
The disk locking code will protect against the only possible
failure mode this doesn't account for (loosing conenctivity to
libvirtd after Finish3 starts the CPUs, but before the client
sees the reply for Finish3).
* src/driver.h, src/libvirt.c, src/libvirt_internal.h: Change
virDomainMigrateFinish3 to return a virDomainPtr instead of int
* src/remote/remote_driver.c, src/remote/remote_protocol.x,
daemon/remote.c, src/qemu/qemu_driver.c, src/qemu/qemu_migration.c:
Update for API change
When doing migration, if an error occurs in Perform, it must not
be overwritten during Finish/Confirm steps. If an error occurs
in Finish, it must not be overwritten in Confirm.
Previous commit a9d12c2444 added
code to qemudDomainMigrateFinish2 to preserve the error. This
is not the right place, because it is not applicable in non-p2p
migration. The src/libvirt.c virDomainMigrateV2/3 methods need
code to preserve errors for non-p2p migration, while the
doPeer2PeerMigrate2 and doPeer2PeerMigrate3 methods contain
code to preverse errors for p2p migration.
Remove the bogus error preservation from qemudDomainMigrateFinish2
and qemudDomainMigrateFinish3.
Fix virDomainMigrateV3 and doPeer2PeerMigrate3 so that they
preserve any error hit during the Finish3 step, before invoking
Confirm3.
Finally if qemuMigrationFinish fails to resume the CPUs, it must
preserve the error before tearing down the VM, so that VM cleanup
doesn't overwrite it.
* src/libvirt.c: Preserve error before invoking Confirm3
* src/qemu/qemu_driver.c: Remove bogus error preservation
code in qemudDomainMigrateFinish2/qemudDomainMigrateFinish3
* src/qemu/qemu_migration.c: Preserve error before invoking Confirm3
and after resume fails in qemuMigrationFinish.
* src/libvirt.c: Add further debug lines in helper APIs for
migration
* src/qemu/qemu_migration.c: Add debug lines for all internal
migration API parameters
Even when failing to start CPUs, the finish method was returning
a success result. Fix this so that the QEMU process is killed
off when finish fails under v3 protocol. Also rename the
killOnFinish boolean to 'v3proto' to make it clearer that this
is a tunable based on the migration protocol version
* src/qemu/qemu_driver.c: Update for API change
* src/qemu/qemu_migration.c, src/qemu/qemu_migration.h: Kill
VM in qemuMigrationFinish if failing to start CPUs
The SPICE seamless migration process requires data to be passed
back from the target host, to the source host via a cookie.
The cookie includes the target host's hostname, but this was not
stored, merely validated. This patch explicitly records the
remote hostname after parsing the cookie, and uses it when
initiating the SPICE migration
* qemu/qemu_migration.c: Fix SPICE seamless migration hostname
Before running perform in peer-2-peer migration, the current
guest state must be recorded, so that non-live migration can
currently unpause a running guest on completion.
* src/qemu/qemu_migration.c: Move check for offline guest
to fix non-live migration
The virDomainMigratePerform3 currently has a single URI parameter
whose meaning varies. It is either
- A QEMU migration URI (normal migration)
- A libvirtd connection URI (peer2peer migration)
Unfortunately when using peer2peer migration, without also
using tunnelled migration, it is possible that both URIs are
required.
This adds a second URI parameter to the virDomainMigratePerform3
method, to cope with this scenario. Each parameter how has a fixed
meaning.
NB, there is no way to actually take advantage of this yet,
since virDomainMigrate/virDomainMigrateToURI do not have any
way to provide the 2 separate URIs
* daemon/remote.c, src/remote/remote_driver.c,
src/remote/remote_protocol.x, src/remote_protocol-structs: Add
the second URI parameter to perform3 message
* src/driver.h, src/libvirt.c, src/libvirt_internal.h: Add
the second URI parameter to Perform3 method
* src/libvirt_internal.h, src/qemu/qemu_migration.c,
src/qemu/qemu_migration.h: Update to handle URIs correctly
This extends the v3 migration protocol such that the
virDomainMigrateBegin3 and virDomainMigratePerform3
methods accept an application supplied XML config for
the target VM.
If the 'xmlin' parameter is NULL, then Begin3 uses the
current guest XML as normal. A driver implementing the
Begin3 method should either reject all non-NULL 'xmlin'
parameters, or strictly validate that the app supplied
XML does not change guest ABI.
The Perform3 method also needed the xmlin parameter to
cope with the Peer2Peer migration sequence.
NB it is not yet possible to use this capability since
neither of the public virDomainMigrate/virDomainMigrateToURI
methods have a way to pass in XML.
* daemon/remote.c, src/remote/remote_driver.c,
src/remote/remote_protocol.x, src/remote_protocol-structs:
Add 'remote_string xmlin' parameter to begin3/perform3
RPC messages
* src/libvirt.c, src/driver.h, src/libvirt_internal.h: Add
'const char *xmlin' parameter to Begin3/Perform3 methods
* src/qemu/qemu_driver.c, src/qemu/qemu_migration.c,
src/qemu/qemu_migration.h: Pass xmlin parameter around
migration methods
The qemuMigrationConfirm method shouldn't deal with final VM
cleanup, since it can be called from the peer2peer migration,
which expects to still use the 'vm' object afterwards.
Push the cleanup code out of qemuMigrationConfirm, into its
caller, qemuDomainMigrateConfirm3
* src/qemu/qemu_driver.c: Add VM cleanup code to
qemuDomainMigrateConfirm3
* src/qemu/qemu_migration.c, src/qemu/qemu_migration.h: Remove
job handling cleanup from qemuMigrationConfirm
To allow new mandatory migration cookie data to be introduced,
add support for checking supported feature flags when parsing
migration cookie.
* src/qemu/qemu_migration.c: Feature flag checking in migration
cookie parsing
When generating a cookie for a guest with no data, the
QEMU_MIGRATION_COOKIE_GRAPHICS flag was set even if no
graphics data was added. Avoid setting the flag unless
it was needed, also add a safety check for mig->graphics
being non-NULL
* src/qemu/qemu_migration.c: Avoid cookie crash for guest
with no graphics
By running the doTunnelSendAll code in a separate thread, the
main thread can do qemuMigrationWaitForCompletion as with
normal migration. This in turn ensures that job signals work
correctly and that progress monitoring can be done
* src/qemu/qemu_migration.c: Run tunnelled migration in
separate thread
Cancelling the QEMU migration may cause QEMU to flush pending
data on the migration socket. This may in turn block QEMU if
nothing reads from the other end of the socket. Closing the
socket before cancelling QEMU migration avoids this possible
deadlock.
* src/qemu/qemu_migration.c: Close sockets before cancelling
migration on failure
The 'nbytes' variable was not re-initialized to the
buffer size on each iteration of the tunnelled migration
loop. While saferead() will ensure a full read, except
on EOF, it is clearer to use the real buffer size
* src/qemu/qemu_migration.c: Always read full buffer of data
The qemuMigrationWaitForCompletion method contains a loop which
repeatedly queries QEMU to check migration progress, and also
processes job signals (pause, setspeed, setbandwidth, cancel).
The tunnelled migration loop does not currently support this
functionality, but should. Refactor the code to allow it to
be used with tunnelled migration.
Implement the v3 migration protocol, which has two extra
steps, 'begin' on the source host and 'confirm' on the
source host. All other methods also gain both input and
output cookies to allow bi-directional data passing at
all stages.
The QEMU peer2peer migration method gains another impl
to provide the v3 migration. This finally allows migration
cookies to work with tunnelled migration, which is required
for Spice seamless migration & the lock manager transfer
* src/qemu/qemu_driver.c: Wire up migrate v3 APIs
* src/qemu/qemu_migration.c, src/qemu/qemu_migration.h: Add
begin & confirm methods, and peer2peer impl of v3
