Add two src->dest commands:
   * OPEN_RETURN_PATH - To request that the destination open the return path
   * PING - Request an acknowledge from the destination
Signed-off-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NAmit Shah <amit.shah@redhat.com>
Reviewed-by: NJuan Quintela <quintela@redhat.com>
Signed-off-by: NJuan Quintela <quintela@redhat.com>

Create QEMU_VM_COMMAND section type for sending commands from
source to destination.  These commands are not intended to convey
guest state but to control the migration process.

For use in postcopy.
Signed-off-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NAmit Shah <amit.shah@redhat.com>
Reviewed-by: NJuan Quintela <quintela@redhat.com>
Signed-off-by: NJuan Quintela <quintela@redhat.com>

In postcopy we're going to need to perform the complete phase
for postcopiable devices at a different point, start out by
renaming all of the 'complete's to make the difference obvious.
Signed-off-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NAmit Shah <amit.shah@redhat.com>
Reviewed-by: NJuan Quintela <quintela@redhat.com>
Signed-off-by: NJuan Quintela <quintela@redhat.com>

Suspend to file is very much like a migrate, and it makes life
easier if we have the Migration state available, so initialise it
in the savevm.c code for suspending.
Signed-off-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NDavid Gibson <david@gibson.dropbear.id.au>
Reviewed-by: NJuan Quintela <quintela@redhat.com>
Reviewd-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NJuan Quintela <quintela@redhat.com>

The vmstate_configuration is currently written
in 'qemu_savevm_state_begin', move it to
'qemu_savevm_state_header' since it's got a hard
requirement that it must be the 1st thing after
the header.
(In postcopy some 'command' sections get sent
early before the saving of the main sections
and hence before qemu_savevm_state_begin).
Signed-off-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NAmit Shah <amit.shah@redhat.com>
Reviewed-by: NJuan Quintela <quintela@redhat.com>
Signed-off-by: NJuan Quintela <quintela@redhat.com>

'cleanup' seems more appropriate than 'cancel'.
Signed-off-by: NLiang Li <liang.z.li@intel.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>al3
Reviewed-by: Amit Shah <amit.shah@redhat.com>al3
Signed-off-by: Juan Quintela <quintela@redhat.com>al3

The function qemu_savevm_state_cancel is called after the migration
in migration_thread, it seems strange to 'cancel' it after completion,
rename it to qemu_savevm_state_cleanup looks better.
Signed-off-by: NLiang Li <liang.z.li@intel.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>al3
Reviewed-by: Amit Shah <amit.shah@redhat.com>al3
Signed-off-by: Juan Quintela <quintela@redhat.com>al3

g_new(T, n) is neater than g_malloc(sizeof(T) * n).  It's also safer,
for two reasons.  One, it catches multiplication overflowing size_t.
Two, it returns T * rather than void *, which lets the compiler catch
more type errors.

This commit only touches allocations with size arguments of the form
sizeof(T).  Same Coccinelle semantic patch as in commit b45c03f5.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Message-Id: <1442231491-23352-1-git-send-email-armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: Nzhanghailiang <zhang.zhanghailiang@huawei.com>
Reviewed-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NAmit Shah <amit.shah@redhat.com>

This is a start on using size_t more in qemu-file and friends;
it fixes up QEMUFilePutBufferFunc and QEMUFileGetBufferFunc
to take size_t lengths and return ssize_t return values (like read(2))
and fixes up all the different implementations of them.

Note that I've not yet followed this deeply into bdrv_ implementations.
Signed-off-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <1439463094-5394-5-git-send-email-dgilbert@redhat.com>
Reviewed-by: Nzhanghailiang <zhang.zhanghailiang@huawei.com>
Reviewed-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NAmit Shah <amit.shah@redhat.com>

The free() and g_free() functions both happily accept
NULL on any platform QEMU builds on. As such putting a
conditional 'if (foo)' check before calls to 'free(foo)'
merely serves to bloat the lines of code.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NMichael Tokarev <mjt@tls.msk.ru>

When doing migration via the QMP command xen_save_devices_state, the
current runstate is not store into the global state section. Also the
current runstate is not the one we want on the receiver side.

During migration, the Xen toolstack paused QEMU before save the devices
state. Also, the toolstack expect QEMU to autostart when the migration is
finished.
So this patch store "running" as it's current runstate.
Signed-off-by: NAnthony PERARD <anthony.perard@citrix.com>
Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>

Commit df4b1024 introduced global_state
section.  But it only filled the state while doing migration.  While
doing a savevm, we stored an empty string as state.  So when we did a
loadvm, it complained that state was invalid.

Fedora 21, 4.1.1, qemu 2.4.0-rc0
> ../../configure --target-list="x86_64-softmmu"

068 2s ... - output mismatch (see 068.out.bad)
--- /home/bos/jhuston/src/qemu/tests/qemu-iotests/068.out	2015-07-08
17:56:18.588164979 -0400
+++ 068.out.bad	2015-07-09 17:39:58.636651317 -0400
@@ -6,6 +6,8 @@
 QEMU X.Y.Z monitor - type 'help' for more information
 (qemu) savevm 0
 (qemu) quit
+qemu-system-x86_64: Unknown savevm section or instance 'globalstate' 0
+qemu-system-x86_64: Error -22 while loading VM state
 QEMU X.Y.Z monitor - type 'help' for more information
 (qemu) quit
 *** done
Failures: 068
Failed 1 of 1 tests

Actually, there were two problems here:
- we registered global_state too late for load_vm (fixed on another
  patch on the list)
- we didn't store a valid state for savevm (fixed by this patch).
Reported-by: NJohn Snow <jsnow@redhat.com>
Signed-off-by: NJuan Quintela <quintela@redhat.com>
Reviewed-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NAmit Shah <amit.shah@redhat.com>
Tested-by: NChristian Borntraeger <borntraeger@de.ibm.com>

The section footers check was incorrectly checking the section_id
in the SaveStateEntry not the LoadStateEntry.  These can validly be different
if the two QEMU instances have instantiated their devices in a
different order.  The test only cares that we're finishing the same
section we started, and hence it's the LoadStateEntry that we care about.
Signed-off-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Reported-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NJuan Quintela <quintela@redhat.com>

It needs to be the first one and it is not optional, that is the reason
why it is opencoded.  For new machine types, it is required that machine
type name is the same in both sides.

It is just done right now for pc's.
Signed-off-by: NJuan Quintela <quintela@redhat.com>
Reviewed-by: NDr. David Alan Gilbert <dgilbert@redhat.com>

To make sections optional, we need to do it at the beggining of the code.
Signed-off-by: NJuan Quintela <quintela@redhat.com>
Reviewed-by: NDr. David Alan Gilbert <dgilbert@redhat.com>

The VMDescription section maybe after the EOF mark, the current code
does a 'qemu_get_byte' and either gets the header byte identifying the
description or an error (which it ignores).  Doing the 'get' upsets
RDMA which hangs on old machine types without the VMDescription.

Just avoid reading the VMDescription if we wouldn't send it.
Signed-off-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: NJuan Quintela <quintela@redhat.com>

In particular, don't include it into headers.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NLuiz Capitulino <lcapitulino@redhat.com>

Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NLuiz Capitulino <lcapitulino@redhat.com>

These macros expand into error class enumeration constant, comma,
string.  Unclean.  Has been that way since commit 13f59ae8.

The error class is always ERROR_CLASS_GENERIC_ERROR since the previous
commit.

Clean up as follows:

* Prepend every use of a QERR_ macro by ERROR_CLASS_GENERIC_ERROR, and
  delete it from the QERR_ macro.  No change after preprocessing.

* Rewrite error_set(ERROR_CLASS_GENERIC_ERROR, ...) into
  error_setg(...).  Again, no change after preprocessing.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NLuiz Capitulino <lcapitulino@redhat.com>

Badly formatted migration streams can go undetected or produce
misleading errors due to a lock of checking at the end of sections.
In particular a section that adds an extra 0x00 at the end
causes what looks like a normal end of stream and thus doesn't produce
any errors, and something that ends in a 0x01..0x04 kind of look
like real section headers and then fail when the section parser tries
to figure out which section they are.  This is made worse by the
choice of 0x00..0x04 being small numbers that are particularly common
in normal section data.

This patch adds a section footer consisting of a marker (0x7e - ~)
followed by the section-id that was also sent in the header.  If
they mismatch then it throws an error explaining which section was
being loaded.
Signed-off-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NJuan Quintela <quintela@redhat.com>
Signed-off-by: NJuan Quintela <quintela@redhat.com>

The next patch adds section footers; but we don't want to
break migration compatibility so disable them on older
machine types
Signed-off-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NJuan Quintela <quintela@redhat.com>
Signed-off-by: NJuan Quintela <quintela@redhat.com>

The header writing for device sections is open coded in
a few places, merge it into one.
Signed-off-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NJuan Quintela <quintela@redhat.com>
Signed-off-by: NJuan Quintela <quintela@redhat.com>

In postcopy we need the loadvm_handlers to be used in a couple
of different instances of the loadvm loop/routine, and thus
it can't be local any more.
Signed-off-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NDavid Gibson <david@gibson.dropbear.id.au>
Reviewed-by: NJuan Quintela <quintela@redhat.com>
Signed-off-by: NJuan Quintela <quintela@redhat.com>

There are currently lots of pieces of incoming migration state scattered
around, and postcopy is adding more, and it seems better to try and keep
it together.

allocate MIS in process_incoming_migration_co
Signed-off-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NAmit Shah <amit.shah@redhat.com>
Reviewed-by: NDavid Gibson <david@gibson.dropbear.id.au>
Reviewed-by: NJuan Quintela <quintela@redhat.com>
Signed-off-by: NJuan Quintela <quintela@redhat.com>

Split qemu_savevm_state_begin to:
  qemu_savevm_state_header   That writes the initial file header.
  qemu_savevm_state_begin    That sets up devices and does the first
                             device pass.

Used later in postcopy.
Signed-off-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NAmit Shah <amit.shah@redhat.com>
Reviewed-by: NDavid Gibson <david@gibson.dropbear.id.au>
Reviewed-by: NJuan Quintela <quintela@redhat.com>
Signed-off-by: NJuan Quintela <quintela@redhat.com>

and use it in loadvm_state and ram_load.

Where ever it's used, check the return and error if it failed.

Minor: ram_load was using a 257 byte array for its string, the
       maximum length is 255 bytes + 0 terminator, so fix to 256
Signed-off-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: NAmit Shah <amit.shah@redhat.com>
Reviewed-by: NDavid Gibson <david@gibson.dropbear.id.au>
Reviewed-by: NJuan Quintela <quintela@redhat.com>
Signed-off-by: NJuan Quintela <quintela@redhat.com>

We create optional sections with this patch.  But we already have
optional subsections.  Instead of having two mechanism that do the
same, we can just generalize it.

For subsections we just change:

- Add a needed function to VMStateDescription
- Remove VMStateSubsection (after removal of the needed function
  it is just a VMStateDescription)
- Adjust the whole tree, moving the needed function to the corresponding
  VMStateDescription
Signed-off-by: NJuan Quintela <quintela@redhat.com>

This way, we will put savevm global state here, instead of lots of variables.
Signed-off-by: NJuan Quintela <quintela@redhat.com>
Reviewed-by: NDr. David Alan Gilbert <dgilbert@redhat.com>

If anyone feels like adding himself to the list, just sent me a patch.
Signed-off-by: NJuan Quintela <quintela@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

Now, everything is in place.
Signed-off-by: NJuan Quintela <quintela@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

This is a continuation of the work started in commit 565f65d2:
"error: Use error_report_err() where appropriate"
Signed-off-by: Nzhanghailiang <zhang.zhanghailiang@huawei.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NMichael Tokarev <mjt@tls.msk.ru>

We now always send a JSON blob describing the migration file format as part
of the migration stream. However, some tools built around QEMU have proven
to stumble over this.

This patch gives the user the chance to disable said self-describing part of
the migration stream. To disable vmdesc submission, just add

  -machine suppress-vmdesc=on

to your QEMU command line.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NJuan Quintela <quintela@redhat.com>

One of the really nice things about the VM description format is that it goes
over the wire when live migration is happening. Unfortunately QEMU today closes
any socket once it sees VM_EOF coming, so we never give the VMDESC the chance to
actually land on the wire.

This patch makes QEMU read the description as well. This way we ensure that
anything wire tapping us in between will get the chance to also interpret the
stream.

Along the way we also fix virt tests that assume that number_bytes_sent on the
sender side is equal to number_bytes_read which was true before the VMDESC
patches and is true again with this patch.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Reviewed-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Tested-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: NJuan Quintela <quintela@redhat.com>

Some are called do_info_SUBCOMMAND() (old ones, usually), some
hmp_info_SUBCOMMAND(), some SUBCOMMAND_info(), sometimes SUBCOMMAND
pointlessly differs in spelling.

Normalize to hmp_info_SUBCOMMAND(), where SUBCOMMAND is exactly the
subcommand name with '-' replaced by '_'.

Exceptions:

* sun4m_irq_info(), sun4m_pic_info() renamed to sun4m_hmp_info_irq(),
  sun4m_hmp_info_pic().

* lm32_irq_info(), lm32_pic_info() renamed to lm32_hmp_info_irq(),
  lm32_hmp_info_pic().
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>

Some are called do_COMMAND() (old ones, usually), some hmp_COMMAND(),
and sometimes COMMAND pointlessly differs in spelling.

Normalize to hmp_COMMAND(), where COMMAND is exactly the command name
with '-' replaced by '_'.

Exceptions:

* do_device_add() and client_migrate_info() *not* renamed to
  hmp_device_add(), hmp_client_migrate_info(), because they're also
  QMP handlers.  They still need to be converted to QAPI.

* do_memory_dump(), do_physical_memory_dump(), do_ioport_read(),
  do_ioport_write() renamed do hmp_* instead of hmp_x(), hmp_xp(),
  hmp_i(), hmp_o(), because those names are too cryptic for my taste.

* do_info_help() renamed to hmp_info_help() instead of hmp_info(),
  because it only covers help.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>

If an internal snapshot can't be saved because migration is blocked
(most commonly probably because of AHCI), we had a really bad error
message:

$ echo -e "savevm foo\nquit" | qemu -M q35 /tmp/test.qcow2 -monitor stdio
QEMU 2.2.50 monitor - type 'help' for more information
(qemu) savevm foo
Error -22 while writing VM
(qemu) quit

This patch converts qemu_savevm_state() to the Error infrastructure so
that a useful error pointing to the problematic device is produced now:

$ echo -e "savevm foo\nquit" | qemu -M q35 /tmp/test.qcow2 -monitor stdio
QEMU 2.2.50 monitor - type 'help' for more information
(qemu) savevm foo
State blocked by non-migratable device '0000:00:1f.2/ich9_ahci'
(qemu) quit
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-id: 1423574702-23072-1-git-send-email-kwolf@redhat.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

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: NAlexander Graf <agraf@suse.de>
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NJuan Quintela <quintela@redhat.com>

Signed-off-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NJuan Quintela <quintela@redhat.com>

Mostly on the load side, so that when we get a complaint about
a migration failure we can figure out what it didn't like.
Signed-off-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NJuan Quintela <quintela@redhat.com>

Convert a bunch of fprintfs to error_reports
Signed-off-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NJuan Quintela <quintela@redhat.com>