The VIR_MIGRATE_PARALLEL flag is implemented using QEMU's multifd
migration capability and the corresponding multifd-channels migration
parameter.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>

The qemuMigrationParamsApply internal API was designed to apply all
migration parameters and capabilities before we start to migrate a
domain. While migration parameters are only passed to QEMU when we
explicitly want to set a specific value, capabilities are always either
enabled or disabled.

Thus when this API is called outside migration job, e.g., via a call to
qemuDomainMigrateSetMaxSpeed with VIR_DOMAIN_MIGRATE_MAX_SPEED_POSTCOPY
flag, we would call migrate-set-capabilities and disable all
capabilities. However, changing capabilities while migration is already
running does not make sense and our code should never be trying to do
so. In fact QEMU even reports an error if migrate-set-capabilities is
called during migration and qemuDomainMigrateSetMaxSpeed would fail
with:

    internal error: unable to execute QEMU command
    migrate-set-capabilities: There's a migration process in progress

With this patch qemuMigrationParamsApply never tries to call
migrate-set-capabilities outside of migration job. When the capabilities
bitmap is all zeros (which is its initial value after
qemuMigrationParamsNew), we just skip the command. But when any
capability bit is set to 1 by a non-migration job, we report an error to
highlight a bug in our code.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Acked-by: NPeter Krempa <pkrempa@redhat.com>

Instead of repetitive:
  s ? s : ""
use NULLSTR_EMPTY.
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NAndrea Bolognani <abologna@redhat.com>

This typed parameter for virDomainMigrate3 and virDomainMigrateToURI3
APIs may be used for setting maximum post-copy migration bandwidth.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

So far migration parameters were changed only at the beginning of
migration mostly via an automatic translation from flags and typed
parameters. We need to export a few more functions to support APIs which
may set migration parameters while migration is already running.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Some migration parameters supported by libvirt may use units that differ
from the units used by QEMU for the corresponding parameters. For
example, libvirt defines migration bandwidth in MiB/s while QEMU expects
B/s. Let's add a unit field to qemuMigrationParamsTPMapItem for
automatic conversion when translating between libvirt's migration typed
parameters and QEMU's migration paramteres.

This patch is a preparation for future parameters as the existing
VIR_MIGRATE_PARAM_BANDWIDTH parameter is set using "migrate_set_speed"
QMP command rather than "migrate-set-parameters" for backward
compatibility.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Missing semicolon at the end of macros can confuse some analyzers
(like cppcheck <filename>), and we have a mix of semicolon and
non-semicolon usage through the code. Let's standardize on using
a semicolon for VIR_ENUM_DECL calls.

Drop the semicolon from the final statement of the macro, so
the compiler will require callers to add a semicolon.
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>
Signed-off-by: NCole Robinson <crobinso@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: NDaniel P. Berrangé <berrange@redhat.com>

This introduces a syntax-check script that validates header files use a
common layout:

  /*
   ...copyright header...
   */
  <one blank line>
  #ifndef SYMBOL
  # define SYMBOL
  ....content....
  #endif /* SYMBOL */

For any file ending priv.h, before the #ifndef, we will require a
guard to prevent bogus imports:

  #ifndef SYMBOL_ALLOW
  # error ....
  #endif /* SYMBOL_ALLOW */
  <one blank line>

The many mistakes this script identifies are then fixed.
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

Libvirt relies on being able to kill the destination domain and resume
the source one during migration until we called "cont" on the
destination. Unfortunately, QEMU automatically activates block devices
at the end of migration even when it's called with -S. This wasn't a big
issue in the past since the guest is not running and thus no data are
written to the block devices. However, when QEMU introduced its internal
block device locks, we can no longer resume the source domain once the
destination domain already activated the block devices (and thus
acquired all locks) unless the destination domain is killed first.

Since it's impossible to synchronize the destination and the source
libvirt daemons after a failed migration, QEMU introduced a new
migration capability called "late-block-activate" which ensures QEMU
won't activate block devices until it gets "cont". The only thing we
need to do is to enable this capability whenever QEMU supports it.

https://bugzilla.redhat.com/show_bug.cgi?id=1568407

QEMU commit implementing the capability: v2.12.0-952-g0f073f44df
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Note that it's okay to pass NULL to qemuDomainDelTLSObjects in
qemuDomainAddTLSObjects as the tls-creds-x509 object was either not
created or qemu crashed.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Callers should generate the alias separately.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

No callers are using it.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

The alias of the secret for decrypting the TLS passphrase is useless
besides for TLS setup. Stop passing it around.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

We allocate a temporary bitmap but never free it.

Introduced by <commit 1f8a1a95>:
    qemu: Do not use qemuMonitorSetMigrationCapability
Signed-off-by: NJán Tomko <jtomko@redhat.com>

The code setting TLS parameters verifies that TLS is supported by
looking at the dump of parameters which will be reset after migration,
but sets the parameters in the list of new parameters. As
qemuMigrationParamsSetString did not set the 'set' property, the TLS
parameters would not be used.

This is a regression after the series refactoring migration parameters
and it resulted into TLS not being used even when requested.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>

The function is not used outside of the src/qemu/qemu_migration_params.c
file so unexport it.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>

If virJSONValueArraySize(caps) <= 0, then we will still need to
virJSONValueFree(caps) because qemuMonitorSetMigrationCapabilities
won't consume it.

Found by Coverity
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>

Trying to delete the non-existent TLS objects results in ugly error
messages in the log, which could easily confuse users. Let's avoid this
confusion by not trying to delete the objects if we were not asked to
enable TLS migration and thus we didn't created the objects anyway.

This patch restores the behavior to the state before "qemu: Reset all
migration parameters".
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

To be able to restore all migration parameters when libvirtd is
restarting during an active migration job, we need to store the original
values of all parameters (stored in priv->job.migParams) in the status
XML.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Most QEMU migration parameters directly correspond to
VIR_MIGRATE_PARAM_* typed parameters and qemuMigrationParamsFromFlags
can automatically set them according to a static mapping between libvirt
and QEMU parameters.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

The API is renamed as qemuMigrationParamsGetULL and it can be used with
any migration parameter stored as unsigned long long.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

When an always-on migration capability is supposed to be enabled on both
sides of migration, each side can only enable the feature if it is
enabled by the other side.

Thus the source host sends a list of supported migration capabilities in
the migration cookie generated in the Begin phase. The destination host
consumes the list in the Prepare phase and decides what capabilities can
be enabled when starting a QEMU process for incoming migration. Once
done the destination sends the list of supported capabilities back to
the source where it is used during the Perform phase to determine what
capabilities can be automatically enabled.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Some migration capabilities may be enabled automatically, but only if
both sides of migration support them. Thus we need to be able transfer
the list of supported migration capabilities in migration cookie.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Since the monitor code no longer needs to see this enum, we move it
to the place where migration parameters are defined and drop the
"monitor" reference from the name.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

We want to have all migration capabilities parsing and formatting at one
place, i.e., in qemu_migration_params.c. The parsing is already there in
qemuMigrationCapsCheck.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Adding support for new migration parameter requires a lot of places to
be changed (most likely by copy&paste engineering): new variables to
store the parameter value and the associated *_set bool, JSON formatter
and parser, XML formatter and parser (to be added soon), and the actual
code to set the parameter. It's pretty easy to forget about some of the
places which need to be updated and end up with incorrect support. The
goal of this patch is to let most of the places do their job without any
modifications when new parameters are added.

To achieve the goal, a new qemuMigrationParam enum is introduced and all
parameters are stored in an array indexed by the items of this enum.
This will also allow us to automatically set the migration parameters
which directly correspond to libvirt's typed parameters accepted by
virDomainMigrate* APIs.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

It's no longer used by the monitor code so we can hide it inside
qemu_migration_params.c.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

We want to have all migration parameters parsing and formatting at one
place, i.e., in qemu_migration_params.c.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

We want to have all migration parameters parsing and formatting at once
place, i.e., in qemu_migration_params.c.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Use this internal structure only in qemu_migration_params.c and change
other non-test users to use the high level qemuMigrationParams struct.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Let's separate the code which queries QEMU for migration parameters from
qemuMigrationParamsCheck into a dedicated function.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

By merging qemuMigrationAnyCompressionParse into
qemuMigrationParamsSetCompression we can drop the useless intermediate
qemuMigrationCompression structure and parse compression related typed
parameters and flags directly into qemuMigrationParams.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Since every parameter or capability set in qemuMigrationCompression
structure is now reflected in qemuMigrationParams structure, we can
replace qemuMigrationAnyCompressionDump with a new API which will work
on qemuMigrationParams.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

There's no need to call this API explicitly in the migration code. We
can pass the compression parameters to qemuMigrationParamsFromFlags and
it can internally call qemuMigrationParamsSetCompression to apply them
to the qemuMigrationParams structure.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

The code really belongs to qemu_migration_params.c.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

The API will soon be called from qemuMigrationParamsFromFlags. Let's
move it to avoid the need to add a forward declaration.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>