Use block_job_add_bdrv() instead of blocking all operations in
mirror_start_job() and unblocking them in mirror_exit().
Signed-off-by: NAlberto Garcia <berto@igalia.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

When a block job is created on a certain BlockDriverState, operations
are blocked there while the job exists. However, some block jobs may
involve additional BDSs, which must be blocked separately when the job
is created and unblocked manually afterwards.

This patch adds block_job_add_bdrv(), that simplifies this process by
keeping a list of BDSs that are involved in the specified block job.
Signed-off-by: NAlberto Garcia <berto@igalia.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

When a BlockDriverState is about to be reopened it can trigger certain
operations that need to write to disk. During this process a different
block job can be woken up. If that block job completes and also needs
to call bdrv_reopen() it can happen that it needs to do it on the same
BlockDriverState that is still in the process of being reopened.

This can have fatal consequences, like in this example:

  1) Block job A starts and sleeps after a while.
  2) Block job B starts and tries to reopen node1 (a qcow2 file).
  3) Reopening node1 means flushing and replacing its qcow2 cache.
  4) While the qcow2 cache is being flushed, job A wakes up.
  5) Job A completes and reopens node1, replacing its cache.
  6) Job B resumes, but the cache that was being flushed no longer
     exists.

This patch splits the bdrv_drain_all() call to keep all block jobs
paused during bdrv_reopen_multiple(), so that step 4 can never happen
and the operation is safe.

Note that this scenario can only happen if both bdrv_reopen() calls
are made by block jobs on the same backing chain. Otherwise there's no
chance that the same BlockDriverState appears in both reopen queues.
Signed-off-by: NAlberto Garcia <berto@igalia.com>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

bdrv_drain_all() doesn't allow the caller to do anything after all
pending requests have been completed but before block jobs are
resumed.

This patch splits bdrv_drain_all() into _begin() and _end() for that
purpose. It also adds aio_{disable,enable}_external() calls to disable
external clients in the meantime.

An important restriction of this split is that no new block jobs or
BlockDriverStates can be created between the bdrv_drain_all_begin()
and bdrv_drain_all_end() calls. This is not a concern now because
we'll only be using this in bdrv_reopen_multiple(), but it must be
dealt with if we ever have other uses cases in the future.
Signed-off-by: NAlberto Garcia <berto@igalia.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Introduce new object 'BlockdevOptionsSsh' in qapi/block-core.json to
support blockdev-add for SSH network protocol driver. Use only 'struct
InetSocketAddress' since SSH only supports connection over TCP.
Signed-off-by: NAshijeet Acharya <ashijeetacharya@gmail.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
[ kwolf: Removed host_key_check option, we want to expose this later in
  a structured way rather than as a string that must be parsed ]
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Drop the use of legacy options in favour of the InetSocketAddress
options.
Signed-off-by: NAshijeet Acharya <ashijeetacharya@gmail.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Add InetSocketAddress compatibility to SSH driver.

Add a new option "server" to the SSH block driver which then accepts
a InetSocketAddress.

"host" and "port" are supported as legacy options and are mapped to
their InetSocketAddress representation.
Signed-off-by: NAshijeet Acharya <ashijeetacharya@gmail.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Make inet_connect_saddr() in util/qemu-sockets.c public in order to be
able to use it with InetSocketAddress sockets outside of
util/qemu-sockets.c independently.
Signed-off-by: NAshijeet Acharya <ashijeetacharya@gmail.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

We have 5 options plus ("server") option which is added in the next
patch that conflict with specifying a SSH filename. We need to iterate
over all the options to check whether its key has an "server." prefix.

This iteration will help us adding the new option "server" easily.
Signed-off-by: NAshijeet Acharya <ashijeetacharya@gmail.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Two PCI fixes/improvements for s390x.

# gpg: Signature made Mon 31 Oct 2016 10:09:24 GMT
# gpg:                using RSA key 0xDECF6B93C6F02FAF
# gpg: Good signature from "Cornelia Huck <huckc@linux.vnet.ibm.com>"
# gpg:                 aka "Cornelia Huck <cornelia.huck@de.ibm.com>"
# Primary key fingerprint: C3D0 D66D C362 4FF6 A8C0  18CE DECF 6B93 C6F0 2FAF

* remotes/cohuck/tags/s390x-20161031:
  s390x/pci: Check memory region dispatching callbacks
  s390x/pci: use generic interface to inject interrupt
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Migration bits from the COLO project

# gpg: Signature made Sun 30 Oct 2016 10:39:55 GMT
# gpg:                using RSA key 0xEB0B4DFC657EF670
# gpg: Good signature from "Amit Shah <amit@amitshah.net>"
# gpg:                 aka "Amit Shah <amit@kernel.org>"
# gpg:                 aka "Amit Shah <amitshah@gmx.net>"
# Primary key fingerprint: 48CA 3722 5FE7 F4A8 B337  2735 1E9A 3B5F 8540 83B6
#      Subkey fingerprint: CC63 D332 AB8F 4617 4529  6534 EB0B 4DFC 657E F670

* remotes/amit-migration/tags/migration-for-2.8:
  MAINTAINERS: Add maintainer for COLO framework related files
  configure: Support enable/disable COLO feature
  docs: Add documentation for COLO feature
  COLO: Implement failover work for secondary VM
  COLO: Implement the process of failover for primary VM
  COLO: Introduce state to record failover process
  COLO: Add 'x-colo-lost-heartbeat' command to trigger failover
  COLO: Synchronize PVM's state to SVM periodically
  COLO: Add checkpoint-delay parameter for migrate-set-parameters
  COLO: Load VMState into QIOChannelBuffer before restore it
  COLO: Send PVM state to secondary side when do checkpoint
  COLO: Add a new RunState RUN_STATE_COLO
  COLO: Introduce checkpointing protocol
  COLO: Establish a new communicating path for COLO
  migration: Switch to COLO process after finishing loadvm
  migration: Enter into COLO mode after migration if COLO is enabled
  COLO: migrate COLO related info to secondary node
  migration: Introduce capability 'x-colo' to migration
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Xen 2016/10/28

# gpg: Signature made Sat 29 Oct 2016 02:03:42 BST
# gpg:                using RSA key 0x894F8F4870E1AE90
# gpg: Good signature from "Stefano Stabellini <sstabellini@kernel.org>"
# gpg:                 aka "Stefano Stabellini <stefano.stabellini@eu.citrix.com>"
# Primary key fingerprint: D04E 33AB A51F 67BA 07D3  0AEA 894F 8F48 70E1 AE90

* remotes/sstabellini/tags/xen-20161028-tag:
  xen: Rename xen_be_del_xendev
  xen: Rename xen_be_find_xendev
  xen: Rename xen_be_evtchn_event
  xen: Rename xen_be_send_notify
  xen: Rename xen_be_unbind_evtchn
  xen: Rename xen_be_printf to xen_pv_printf
  xen: Move xenstore cleanup and mkdir functions
  xen: Prepare xendev qtail to be shared with frontends
  xen: Move evtchn functions to xen_pvdev.c
  xen: Move xenstore_update to xen_pvdev.c
  xen: Create a new file xen_pvdev.c
  xen: Fix coding style warnings
  xen: Fix coding style errors
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

trivial patches for 2016-10-28

# gpg: Signature made Fri 28 Oct 2016 16:17:51 BST
# gpg:                using RSA key 0x701B4F6B1A693E59
# gpg: Good signature from "Michael Tokarev <mjt@tls.msk.ru>"
# gpg:                 aka "Michael Tokarev <mjt@corpit.ru>"
# gpg:                 aka "Michael Tokarev <mjt@debian.org>"
# Primary key fingerprint: 6EE1 95D1 886E 8FFB 810D  4324 457C E0A0 8044 65C5
#      Subkey fingerprint: 7B73 BAD6 8BE7 A2C2 8931  4B22 701B 4F6B 1A69 3E59

* remotes/mjt/tags/trivial-patches-fetch: (23 commits)
  Fix build for less common build directories names
  clean-up: removed duplicate #includes
  scripts/clean-includes: added duplicate #include check
  monitor: deprecate 'default' option
  qemu-ga: Remove stray 'q' in documentation
  Makefile: Fix help text for target 'installer'
  s390: avoid always-true comparison in s390_pci_generate_fid()
  migration: Remove unneeded NULL check from migrate_fd_error()
  scripts/hxtool: fix undefined behavour of echo
  qemu-options.hx: set: fix copy-paste error
  usb: Change *_exitfn return type from int to void
  MAINTAINERS: qemu-trivial information
  colo-compare: remove unused struct CompareChardevProps and 'props' variable
  milkymist-pfpu: fix potential integer overflow
  hw/block/nvme: Simplify if-statements a little bit
  target-lm32: rewrite gen_compare()
  lm32: milkymist-tmu2: fix integer overflow
  target-lm32: disable asm logging via LOG_DIS()
  target-lm32: swap operand of wcsr in LOG_DIS()
  target-lm32: fix LOG_DIS operand order
  ...
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

target-arm queue:
 * Fix reset GPIO handling for spitz, tosa boards
 * virt: add 'pmu' property for configuring whether to expose the
   vPMU to the guest
 * char: cadence: correct reset value for baud rate registers
 * versatilepb: do not run if user asks for more than 256MB RAM
 * pxa2xx: Set value default values for CCCR and CKEN on PXA255
 * arm: cubieboard: Add support for initrd
 * i.MX: Fix GPIO ISR register write

# gpg: Signature made Fri 28 Oct 2016 15:56:56 BST
# gpg:                using RSA key 0x3C2525ED14360CDE
# gpg: Good signature from "Peter Maydell <peter.maydell@linaro.org>"
# gpg:                 aka "Peter Maydell <pmaydell@gmail.com>"
# gpg:                 aka "Peter Maydell <pmaydell@chiark.greenend.org.uk>"
# Primary key fingerprint: E1A5 C593 CD41 9DE2 8E83  15CF 3C25 25ED 1436 0CDE

* remotes/pmaydell/tags/pull-target-arm-20161028:
  hw/arm/tosa: Fix reset handling
  hw/arm/spitz: Fix reset handling
  arm: virt: add PMU property to mach-virt machine type
  arm: Add an option to turn on/off vPMU support
  char: cadence: correct reset value for baud rate registers
  versatilepb: do not run if user asks for more than 256MB RAM
  hw/arm/pxa2xx: Set value default values for CCCR and CKEN on PXA255
  arm: cubieboard: Add support for initrd
  i.MX: Fix GPIO ISR register write
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

# gpg: Signature made Fri 28 Oct 2016 15:47:39 BST
# gpg:                using RSA key 0xCA35624C6A9171C6
# gpg: Good signature from "Fam Zheng <famz@redhat.com>"
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg:          There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 5003 7CB7 9706 0F76 F021  AD56 CA35 624C 6A91 71C6

* remotes/famz/tags/for-upstream:
  aio: convert from RFifoLock to QemuRecMutex
  qemu-thread: introduce QemuRecMutex
  iothread: release AioContext around aio_poll
  block: only call aio_poll on the current thread's AioContext
  qemu-img: call aio_context_acquire/release around block job
  qemu-io: acquire AioContext
  block: prepare bdrv_reopen_multiple to release AioContext
  replication: pass BlockDriverState to reopen_backing_file
  iothread: detach all block devices before stopping them
  aio: introduce qemu_get_current_aio_context
  sheepdog: use BDRV_POLL_WHILE
  nfs: use BDRV_POLL_WHILE
  nfs: move nfs_set_events out of the while loops
  block: introduce BDRV_POLL_WHILE
  qed: Implement .bdrv_drain
  block: change drain to look only at one child at a time
  block: add BDS field to count in-flight requests
  mirror: use bdrv_drained_begin/bdrv_drained_end
  blockjob: introduce .drain callback for jobs
  replication: interrupt failover if the main device is closed
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

The instructions PCI STORE, PCI LOAD and PCI STORE BLOCK
use calls to memory_region_dispatch_write() and
memory_region_dispatch_read() but do not test the return value.

Furthermore, the instruction PCI STORE BLOCK sets up a PGM_ADDRESSING
exception when the operand 3 is not within the designated PCI address
space instead of a PGM_OPERAND exception.

Let's setup a PGM_OPERAND exception in all of these failure cases.
Signed-off-by: NPierre Morel <pmorel@linux.vnet.ibm.com>
Signed-off-by: NCornelia Huck <cornelia.huck@de.ibm.com>

Let's use the generic interface to inject adapter interrupts.
Signed-off-by: NYi Min Zhao <zyimin@linux.vnet.ibm.com>
Acked-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: NCornelia Huck <cornelia.huck@de.ibm.com>

Add myself as co-maintainer of COLO framework, so that
I can get CC'ed on future patches and bugs for this feature.
Signed-off-by: Nzhanghailiang <zhang.zhanghailiang@huawei.com>
Reviewed-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NAmit Shah <amit@amitshah.net>

configure --enable-colo/--disable-colo to switch COLO
support on/off.

COLO feature doesn't depend on any other external libraries,
So here it is reasonable to enable COLO by default, to
avoid re-compile QEMU if users want to use this capability.
Signed-off-by: Nzhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: NLi Zhijian <lizhijian@cn.fujitsu.com>
Signed-off-by: NGonglei <arei.gonglei@huawei.com>
Reviewed-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NAmit Shah <amit@amitshah.net>

Introduce the design of COLO, and how to test it.
Signed-off-by: Nzhanghailiang <zhang.zhanghailiang@huawei.com>
Reviewed-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NAmit Shah <amit@amitshah.net>

If users require SVM to takeover work, COLO incoming thread should
exit from loop while failover BH helps backing to migration incoming
coroutine.
Signed-off-by: Nzhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: NLi Zhijian <lizhijian@cn.fujitsu.com>
Reviewed-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NAmit Shah <amit@amitshah.net>

For primary side, if COLO gets failover request from users.
To be exact, gets 'x_colo_lost_heartbeat' command.
COLO thread will exit the loop while the failover BH does the
cleanup work and resumes VM.
Signed-off-by: Nzhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: NLi Zhijian <lizhijian@cn.fujitsu.com>
Reviewed-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NAmit Shah <amit@amitshah.net>

When handling failover, COLO processes differently according to
the different stage of failover process, here we introduce a global
atomic variable to record the status of failover.

We add four failover status to indicate the different stage of failover process.
You should use the helpers to get and set the value.
Signed-off-by: Nzhanghailiang <zhang.zhanghailiang@huawei.com>
Reviewed-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NAmit Shah <amit@amitshah.net>

We leave users to choose whatever heartbeat solution they want,
if the heartbeat is lost, or other errors they detect, they can use
experimental command 'x_colo_lost_heartbeat' to tell COLO to do failover,
COLO will do operations accordingly.

For example, if the command is sent to the Primary side,
the Primary side will exit COLO mode, does cleanup work,
and then, PVM will take over the service work. If sent to the Secondary side,
the Secondary side will run failover work, then takes over PVM's service work.

Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Eric Blake <eblake@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Nzhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: NLi Zhijian <lizhijian@cn.fujitsu.com>
Reviewed-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NAmit Shah <amit@amitshah.net>

Do checkpoint periodically, the default interval is 200ms.
Signed-off-by: Nzhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: NLi Zhijian <lizhijian@cn.fujitsu.com>
Reviewed-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NAmit Shah <amit@amitshah.net>

Add checkpoint-delay parameter for migrate-set-parameters, so that
we can control the checkpoint frequency when COLO is in periodic mode.

Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Eric Blake <eblake@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Nzhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: NLi Zhijian <lizhijian@cn.fujitsu.com>
Reviewed-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NAmit Shah <amit@amitshah.net>

We should not destroy the state of SVM (Secondary VM) until we receive
the complete data of PVM's state, in case the primary fails in the process
of sending the state, so we cache the VM's state in secondary side before
load it into SVM.

Besides, we should call qemu_system_reset() before load VM state,
which can ensure the data is intact.
Signed-off-by: Nzhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: NLi Zhijian <lizhijian@cn.fujitsu.com>
Signed-off-by: NGonglei <arei.gonglei@huawei.com>
Reviewed-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NAmit Shah <amit@amitshah.net>

VM checkpointing is to synchronize the state of PVM to SVM, just
like migration does, we re-use save helpers to achieve migrating
PVM's state to Secondary side.

COLO need to cache the data of VM's state in the secondary side before
synchronize it to SVM. COLO need the size of the data to determine
how much data should be read in the secondary side.
So here, we can get the size of the data by saving it into I/O channel
before send it to the secondary side.
Signed-off-by: Nzhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: NGonglei <arei.gonglei@huawei.com>
Signed-off-by: NLi Zhijian <lizhijian@cn.fujitsu.com>
Reviewed-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NAmit Shah <amit@amitshah.net>

Guest will enter this state when paused to save/restore VM state
under COLO checkpoint.

Cc: Eric Blake <eblake@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Nzhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: NLi Zhijian <lizhijian@cn.fujitsu.com>
Signed-off-by: NGonglei <arei.gonglei@huawei.com>
Reviewed-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NAmit Shah <amit@amitshah.net>

We need communications protocol of user-defined to control
the checkpointing process.

The new checkpointing request is started by Primary VM,
and the interactive process like below:

Checkpoint synchronizing points:

                   Primary               Secondary
                                            initial work
'checkpoint-ready'    <-------------------- @

'checkpoint-request'  @ -------------------->
                                            Suspend (Only in hybrid mode)
'checkpoint-reply'    <-------------------- @
                      Suspend&Save state
'vmstate-send'        @ -------------------->
                      Send state            Receive state
'vmstate-received'    <-------------------- @
                      Release packets       Load state
'vmstate-load'        <-------------------- @
                      Resume                Resume (Only in hybrid mode)

                      Start Comparing (Only in hybrid mode)
NOTE:
 1) '@' who sends the message
 2) Every sync-point is synchronized by two sides with only
    one handshake(single direction) for low-latency.
    If more strict synchronization is required, a opposite direction
    sync-point should be added.
 3) Since sync-points are single direction, the remote side may
    go forward a lot when this side just receives the sync-point.
 4) For now, we only support 'periodic' checkpoint, for which
   the Secondary VM is not running, later we will support 'hybrid' mode.
Signed-off-by: Nzhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: NLi Zhijian <lizhijian@cn.fujitsu.com>
Signed-off-by: NGonglei <arei.gonglei@huawei.com>
Cc: Eric Blake <eblake@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>
Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NAmit Shah <amit@amitshah.net>

This new communication path will be used for returning messages
from Secondary side to Primary side.
Signed-off-by: Nzhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: NLi Zhijian <lizhijian@cn.fujitsu.com>
Reviewed-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NAmit Shah <amit@amitshah.net>

Switch from normal migration loadvm process into COLO checkpoint process if
COLO mode is enabled.

We add three new members to struct MigrationIncomingState,
'have_colo_incoming_thread' and 'colo_incoming_thread' record the COLO
related thread for secondary VM, 'migration_incoming_co' records the
original migration incoming coroutine.
Signed-off-by: Nzhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: NLi Zhijian <lizhijian@cn.fujitsu.com>
Reviewed-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NAmit Shah <amit@amitshah.net>

Add a new migration state: MIGRATION_STATUS_COLO. Migration source side
enters this state after the first live migration successfully finished
if COLO is enabled by command 'migrate_set_capability x-colo on'.

We reuse migration thread, so the process of checkpointing will be handled
in migration thread.
Signed-off-by: Nzhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: NLi Zhijian <lizhijian@cn.fujitsu.com>
Signed-off-by: NGonglei <arei.gonglei@huawei.com>
Reviewed-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NAmit Shah <amit@amitshah.net>

We can determine whether or not VM in destination should go into COLO mode
by referring to the info that was migrated.

We skip this section if COLO is not enabled (i.e.
migrate_set_capability colo off), so that, It doesn't break compatibility
with migration no matter whether users configure the --enable-colo/disable-colo
on the source/destination side or not;
Signed-off-by: Nzhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: NLi Zhijian <lizhijian@cn.fujitsu.com>
Signed-off-by: NGonglei <arei.gonglei@huawei.com>
Reviewed-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NAmit Shah <amit@amitshah.net>

We add helper function colo_supported() to indicate whether
colo is supported or not, with which we use to control whether or not
showing 'x-colo' string to users, they can use qmp command
'query-migrate-capabilities' or hmp command 'info migrate_capabilities'
to learn if colo is supported.

The default value for COLO (COarse-Grain LOck Stepping) is disabled.

Cc: Juan Quintela <quintela@redhat.com>
Cc: Amit Shah <amit.shah@redhat.com>
Cc: Eric Blake <eblake@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Nzhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: NLi Zhijian <lizhijian@cn.fujitsu.com>
Signed-off-by: NGonglei <arei.gonglei@huawei.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NAmit Shah <amit@amitshah.net>

Prepare xen_be_del_xendev to be shared with frontends:
 * xen_be_del_xendev -> xen_pv_del_xendev
Signed-off-by: NEmil Condrea <emilcondrea@gmail.com>
Signed-off-by: NStefano Stabellini <sstabellini@kernel.org>
Signed-off-by: NQuan Xu <xuquan8@huawei.com>
Acked-by: NAnthony PERARD <anthony.perard@citrix.com>

Prepare xen_be_find_xendev to be shared with frontends:
 * xen_be_find_xendev -> xen_pv_find_xendev
Signed-off-by: NEmil Condrea <emilcondrea@gmail.com>
Signed-off-by: NStefano Stabellini <sstabellini@kernel.org>
Signed-off-by: NQuan Xu <xuquan8@huawei.com>
Acked-by: NAnthony PERARD <anthony.perard@citrix.com>

Prepare xen_be_evtchn_event to be shared with frontends:
 * xen_be_evtchn_event -> xen_pv_evtchn_event
Signed-off-by: NEmil Condrea <emilcondrea@gmail.com>
Signed-off-by: NStefano Stabellini <sstabellini@kernel.org>
Signed-off-by: NQuan Xu <xuquan8@huawei.com>
Acked-by: NAnthony PERARD <anthony.perard@citrix.com>

Prepare xen_be_send_notify to be shared with frontends:
 * xen_be_send_notify -> xen_pv_send_notify
Signed-off-by: NEmil Condrea <emilcondrea@gmail.com>
Signed-off-by: NStefano Stabellini <sstabellini@kernel.org>
Signed-off-by: NQuan Xu <xuquan8@huawei.com>
Acked-by: NAnthony PERARD <anthony.perard@citrix.com>

Prepare xen_be_unbind_evtchn to be shared with frontends:
 * xen_be_unbind_evtchn -> xen_pv_unbind_evtchn
Signed-off-by: NEmil Condrea <emilcondrea@gmail.com>
Signed-off-by: NStefano Stabellini <sstabellini@kernel.org>
Signed-off-by: NQuan Xu <xuquan8@huawei.com>
Acked-by: NAnthony PERARD <anthony.perard@citrix.com>