diff options
| author | Alexander Graf <agraf@suse.de> | 2015-01-22 15:01:39 +0100 |
|---|---|---|
| committer | Juan Quintela <quintela@redhat.com> | 2015-02-05 17:16:14 +0100 |
| commit | 8118f0950fc77cce7873002a5021172dd6e040b5 (patch) | |
| tree | 0a8af6231a9ed63c9a33584a1df99c7edccf944a /include | |
| parent | 972214001120e4cf2f4ac35b6ccbd1777b11e060 (diff) | |
migration: Append JSON description of migration stream
One of the annoyances of the current migration format is the fact that
it's not self-describing. In fact, it's not properly describing at all.
Some code randomly scattered throughout QEMU elaborates roughly how to
read and write a stream of bytes.
We discussed an idea during KVM Forum 2013 to add a JSON description of
the migration protocol itself to the migration stream. This patch
adds a section after the VM_END migration end marker that contains
description data on what the device sections of the stream are composed of.
This approach is backwards compatible with any QEMU version reading the
stream, because QEMU just stops reading after the VM_END marker and ignores
any data following it.
With an additional external program this allows us to decipher the
contents of any migration stream and hopefully make migration bugs easier
to track down.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Diffstat (limited to 'include')
| -rw-r--r-- | include/migration/migration.h | 1 | ||||
| -rw-r--r-- | include/migration/vmstate.h | 3 |
2 files changed, 3 insertions, 1 deletions
diff --git a/include/migration/migration.h b/include/migration/migration.h index 3cb5ba80c3..f37348b619 100644 --- a/include/migration/migration.h +++ b/include/migration/migration.h @@ -33,6 +33,7 @@ #define QEMU_VM_SECTION_END 0x03 #define QEMU_VM_SECTION_FULL 0x04 #define QEMU_VM_SUBSECTION 0x05 +#define QEMU_VM_VMDESCRIPTION 0x06 struct MigrationParams { bool blk; diff --git a/include/migration/vmstate.h b/include/migration/vmstate.h index fa307a6c0f..0b26bc68dd 100644 --- a/include/migration/vmstate.h +++ b/include/migration/vmstate.h @@ -29,6 +29,7 @@ #ifndef CONFIG_USER_ONLY #include <migration/qemu-file.h> #endif +#include <qjson.h> typedef void SaveStateHandler(QEMUFile *f, void *opaque); typedef int LoadStateHandler(QEMUFile *f, void *opaque, int version_id); @@ -801,7 +802,7 @@ extern const VMStateInfo vmstate_info_bitmap; int vmstate_load_state(QEMUFile *f, const VMStateDescription *vmsd, void *opaque, int version_id); void vmstate_save_state(QEMUFile *f, const VMStateDescription *vmsd, - void *opaque); + void *opaque, QJSON *vmdesc); int vmstate_register_with_alias_id(DeviceState *dev, int instance_id, const VMStateDescription *vmsd, |