[PATCH v2 00/15] libxl: domain save/restore: run in a separate process

[Ian Jackson <ian.jackson@eu.citrix.com>]

This is v2 of my series to asyncify save/restore.  It appears to work
for me.  Patches 00-05 were posted before.  06-15 are new.

Preparatory work:

 01/15 libxc: xc_domain_restore, make toolstack_restore const-correct
 02/15 libxl: domain save: rename variables etc.
 03/15 libxl: domain restore: reshuffle, preparing for ao
 04/15 libxl: domain save: API changes for asynchrony

The meat:

 05/15 libxl: domain save/restore: run in a separate process

Some fixups:

 06/15 libxl: rename libxl_dom:save_helper to physmap_path
 07/15 libxl: provide libxl__xs_*_checked and libxl__xs_transaction_*
 08/15 libxl: wait for qemu to acknowledge logdirty command

Asyncify writing of qemu save file, too:

 09/15 libxl: datacopier: provide "prefix data" facilit
 10/15 libxl: prepare for asynchronous writing of qemu save file
 11/15 libxl: Make libxl__domain_save_device_model asynchronous

Unrelated bugfixes found during testing:

 12/15 xl: Handle return value from libxl_domain_suspend correctly
 13/15 libxl: do not leak dms->saved_state
 14/15 libxl: do not leak spawned middle children
 15/15 libxl: do not leak an event struct on ignored ao progress

Thanks,
Ian.