Commit Graph

299 Commits

Author SHA1 Message Date
Liang Li
73a8912b8a migration: Fix multi-thread compression bug
Recently, a bug related to multiple thread compression feature for
live migration is reported. The destination side will be blocked
during live migration if there are heavy workload in host and
memory intensive workload in guest, this is most likely to happen
when there is one decompression thread.

Some parts of the decompression code are incorrect:
1. The main thread receives data from source side will enter a busy
loop to wait for a free decompression thread.
2. A lock is needed to protect the decomp_param[idx]->start, because
it is checked in the main thread and is updated in the decompression
thread.

Fix these two issues by following the code pattern for compression.

Signed-off-by: Liang Li <liang.z.li@intel.com>
Reported-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Tested-by: Daniel P. Berrange <berrange@redhat.com>

Signed-off-by: Liang Li <liang.z.li@intel.com>
Message-Id: <1462433579-13691-2-git-send-email-liang.z.li@intel.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-06-17 18:24:01 +05:30
Denis V. Lunev
6dcf66681a migration: fix inability to save VM after snapshot
The following sequence of operations fails:
    virsh start vm
    virsh snapshot-create vm
    virshh save vm --file file
with the following error
    error: Failed to save domain vm to file
    error: internal error: unable to execute QEMU command 'migrate':
    There's a migration process in progress

The problem is that qemu_savevm_state() calls migrate_init() which sets
migration state to MIGRATION_STATUS_SETUP and never cleaned it up.
This patch do the job.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
CC: Juan Quintela <quintela@redhat.com>
CC: Amit Shah <amit.shah@redhat.com>
Message-Id: <1466003203-26263-1-git-send-email-den@openvz.org>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-06-17 18:23:57 +05:30
Dr. David Alan Gilbert
023ad1a6e9 migration: Trace improvements
A couple of improvements to tracing that have come out of helping
people with migration problems:
  * vmstate_n_elems trace the count/name - for when you have problems
    getting array counts right
  * vmstate_subsection_load_bad - add the idstr, for when you receive a
    subsection you weren't expecting.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <1465896986-16132-1-git-send-email-dgilbert@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-06-17 18:23:53 +05:30
Peter Maydell
4d88513157 migration: Don't use *_to_cpup() and cpu_to_*w()
The *_to_cpup() and cpu_to_*w() functions just compose a pointer
dereference with a byteswap. Instead use ld*_p() and st*_p(),
which handle potential pointer misalignment and avoid the need
to cast the pointer.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Message-Id: <1465574962-2710-1-git-send-email-peter.maydell@linaro.org>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-06-17 18:23:49 +05:30
Paolo Bonzini
02d0e09503 os-posix: include sys/mman.h
qemu/osdep.h checks whether MAP_ANONYMOUS is defined, but this check
is bogus without a previous inclusion of sys/mman.h.  Include it in
sysemu/os-posix.h and remove it from everywhere else.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-16 18:39:03 +02:00
Daniel P. Berrange
22724f4921 migration: rename functions to starting migrations
Apply the following renames for starting incoming migration:

 process_incoming_migration -> migration_fd_process_incoming
 migration_set_incoming_channel -> migration_channel_process_incoming
 migration_tls_set_incoming_channel -> migration_tls_channel_process_incoming

and for starting outgoing migration:

 migration_set_outgoing_channel -> migration_channel_connect
 migration_tls_set_outgoing_channel -> migration_tls_channel_connect

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1464776234-9910-3-git-send-email-berrange@redhat.com
Message-Id: <1464776234-9910-3-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-06-16 09:51:37 +05:30
Dr. David Alan Gilbert
096631bd95 Postcopy: Check for support when setting the capability
Knowing whether the destination host supports migration with
postcopy can be tricky.
The destination doesn't need the capability set, however
if we set it then use the opportunity to do the test and
tell the user/management layer early.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-id: 1465816605-29488-7-git-send-email-dgilbert@redhat.com
Message-Id: <1465816605-29488-7-git-send-email-dgilbert@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-06-16 09:50:07 +05:30
Dr. David Alan Gilbert
d3bf5418e2 Postcopy: Add stats on page requests
On the source, add a count of page requests received from the
destination.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Denis V. Lunev <den@openvz.org>
Message-id: 1465816605-29488-4-git-send-email-dgilbert@redhat.com
Message-Id: <1465816605-29488-4-git-send-email-dgilbert@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-06-16 09:50:07 +05:30
Dr. David Alan Gilbert
a22463a5dc Migration: Split out ram part of qmp_query_migrate
The RAM section of qmp_query_migrate is reasonably complex
and repeated 3 times.  Split it out into a helper.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1465816605-29488-3-git-send-email-dgilbert@redhat.com
Reviwed-by: Denis V. Lunev <den@openvz.org>
Message-Id: <1465816605-29488-3-git-send-email-dgilbert@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-06-16 09:50:07 +05:30
Dr. David Alan Gilbert
d688c62d09 Postcopy: Avoid 0 length discards
The discard code in migration/ram.c would send request for
zero length discards in the case where no discards were needed.
It doesn't appear to have had any bad effect.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Denis V. Lunev <den@openvz.org>
Message-id: 1465816605-29488-2-git-send-email-dgilbert@redhat.com
Message-Id: <1465816605-29488-2-git-send-email-dgilbert@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-06-16 09:50:07 +05:30
Wen Congyang
88c16567d2 Introduce "xen-load-devices-state"
Introduce a "xen-load-devices-state" QAPI command that can be used to
load the state of all devices, but not the RAM or the block devices of
the VM.

We only have hmp commands savevm/loadvm, and qmp commands
xen-save-devices-state.

We use this new command for COLO:
1. suspend both primary vm and secondary vm
2. sync the state
3. resume both primary vm and secondary vm

In such case, we need to update all devices' state in any time.

Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Changlong Xie <xiecl.fnst@cn.fujitsu.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
2016-06-13 11:50:53 +01:00
Kevin Wolf
ebd2f9e7db migration/block: Convert saving to BlockBackend
This creates a new BlockBackend for copying data from an images to the
migration stream on the source host. All I/O for block migration goes
through BlockBackend now.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-06-08 10:21:08 +02:00
Kevin Wolf
ad2964b4ff migration/block: Convert load to BlockBackend
This converts the loading part of block migration to use BlockBackend
interfaces rather than accessing the BlockDriverState directly.

Note that this takes a lazy shortcut. We should really use a separate
BlockBackend that is configured for the migration rather than for the
guest (e.g. writethrough caching is unnecessary) and holds its own
reference to the BlockDriverState, but the impact isn't that big and we
didn't have a separate migration reference before either, so it must be
good enough, I guess...

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-06-08 10:21:08 +02:00
Eric Blake
74021bc497 block: Switch bdrv_write_zeroes() to byte interface
Rename to bdrv_pwrite_zeroes() to let the compiler ensure we
cater to the updated semantics.  Do the same for bdrv_co_write_zeroes().

Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-06-08 10:21:08 +02:00
Peter Maydell
030c98aff1 all: Remove unnecessary glib.h includes
Remove glib.h includes, as it is provided by osdep.h.

This commit was created with scripts/clean-includes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Tested-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2016-06-07 18:19:24 +03:00
Paolo Bonzini
f615f39616 exec: remove ram_addr argument from qemu_ram_block_from_host
Of the two callers, one does not use it, and the other can compute
it itself based on the other output argument (offset) and the RAMBlock.

Reviewed-by: Marc-André Lureau <marcandre.lureau@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-29 09:11:12 +02:00
Peter Maydell
aef11b8d33 migration: add TLS support to the migration data channel
This is a big refactoring of the migration backend code - moving away from
 QEMUFile to the new QIOChannel framework introduced here.  This brings a
 good level of abstraction and reduction of many lines of code.
 
 This series also adds the ability for many backends (all except RDMA) to
 use TLS for encrypting the migration data between the endpoints.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2
 
 iQIcBAABCAAGBQJXRpKMAAoJEOsLTfxlfvZw2FMQAJmrp8ijvJNtdBa51bNY+xVx
 zvrHDpWco/HxxqyBIGxG7g8Iq+wpNsdgoRxoQkfgIz9RkZiNrzb1kGRiqNFFBKFX
 ziK1QQQ12ETUXwQ6VguBuwLDvCCenyUti0HfKkceG+Zu5263fyp+VzL+PuEtteT3
 M0pZRrifj/TQqCBXR8yhBAo2dCiFETLVoruE+iNg2ipI3JDizxy8bdOU2gfnTayf
 na7lE53pI+Wy8KE+qrhtsEgjHFp48uJ0HwQIIumvVndXFpIhRzCcN/aeVCjNYRjo
 GeI18OJxcimRDwsnfuOwuZKhRcjWfa8WEIKsi8LdRTZFpFL6y9R57XNTBIFfbjOF
 0lkmFTqJTBi3OTPjj0hMjpjOfXhyKUnwdqCAYlAxeuWHhqPDDhtEcnNtGdmQzx4Z
 KvYzc3t31o1gPin024UUfA528PNREszaXhTM90/Dj0dhVSMoG1VQsQjxzkPXxdM1
 wemfic+77Bk4oUrSplhdvvk4nySDWeseEjfdyVU2ixqldy8Ib1+6H+PCjWNotpQ0
 YiDOHBy3rrUh6NhIqb0C2PWvd/9Aqs0nHQHJ8QKYK574MDbVo8mKTACFdoSYoZ1u
 wuif7NL6qkyS55szf0dm8zPBCJ5nIR5SQE98E7+ptXNa8AipfFsTkZrr3aOjcdey
 98AWF9KaZOWRfwgIm3Ft
 =AYEK
 -----END PGP SIGNATURE-----

Merge remote-tracking branch 'remotes/amit-migration/tags/migration-2.7-2' into staging

migration: add TLS support to the migration data channel

This is a big refactoring of the migration backend code - moving away from
QEMUFile to the new QIOChannel framework introduced here.  This brings a
good level of abstraction and reduction of many lines of code.

This series also adds the ability for many backends (all except RDMA) to
use TLS for encrypting the migration data between the endpoints.

# gpg: Signature made Thu 26 May 2016 07:07:08 BST using RSA key ID 657EF670
# gpg: Good signature from "Amit Shah <amit@amitshah.net>"
# gpg:                 aka "Amit Shah <amit@kernel.org>"
# gpg:                 aka "Amit Shah <amitshah@gmx.net>"

* remotes/amit-migration/tags/migration-2.7-2: (28 commits)
  migration: remove qemu_get_fd method from QEMUFile
  migration: remove support for non-iovec based write handlers
  migration: add support for encrypting data with TLS
  migration: define 'tls-creds' and 'tls-hostname' migration parameters
  migration: don't use an array for storing migrate parameters
  migration: move definition of struct QEMUFile back into qemu-file.c
  migration: delete QEMUFile stdio implementation
  migration: delete QEMUFile sockets implementation
  migration: delete QEMUSizedBuffer struct
  migration: delete QEMUFile buffer implementation
  migration: convert savevm to use QIOChannel for writing to files
  migration: convert RDMA to use QIOChannel interface
  migration: convert exec socket protocol to use QIOChannel
  migration: convert fd socket protocol to use QIOChannel
  migration: convert tcp socket protocol to use QIOChannel
  migration: rename unix.c to socket.c
  migration: convert unix socket protocol to use QIOChannel
  migration: convert post-copy to use QIOChannelBuffer
  migration: add reporting of errors for outgoing migration
  migration: add helpers for creating QEMUFile from a QIOChannel
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-05-26 16:09:27 +01:00
Daniel P. Berrange
12992c16d9 migration: remove qemu_get_fd method from QEMUFile
Now that there is a set_blocking callback in QEMUFileOps,
and all users needing non-blocking support have been
converted to QIOChannel, there is no longer any codepath
requiring the qemu_get_fd() method for QEMUFile. Remove it
to avoid further code being introduced with an expectation
of direct file handle access.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-29-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:32:21 +05:30
Daniel P. Berrange
11808bb0c4 migration: remove support for non-iovec based write handlers
All the remaining QEMUFile implementations provide an iovec
based write handler, so the put_buffer callback can be removed
to simplify the code.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-28-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:32:18 +05:30
Daniel P. Berrange
e122636562 migration: add support for encrypting data with TLS
This extends the migration_set_incoming_channel and
migration_set_outgoing_channel methods so that they
will automatically wrap the QIOChannel in a
QIOChannelTLS instance if TLS credentials are configured
in the migration parameters.

This allows TLS to work for tcp, unix, fd and exec
migration protocols. It does not (currently) work for
RDMA since it does not use these APIs, but it is
unlikely that TLS would be desired with RDMA anyway
since it would degrade the performance to that seen
with TCP defeating the purpose of using RDMA.

On the target host, QEMU would be launched with a set
of TLS credentials for a server endpoint

 $ qemu-system-x86_64 -monitor stdio -incoming defer \
    -object tls-creds-x509,dir=/home/berrange/security/qemutls,endpoint=server,id=tls0 \
    ...other args...

To enable incoming TLS migration 2 monitor commands are
then used

  (qemu) migrate_set_str_parameter tls-creds tls0
  (qemu) migrate_incoming tcp:myhostname:9000

On the source host, QEMU is launched in a similar
manner but using client endpoint credentials

 $ qemu-system-x86_64 -monitor stdio \
    -object tls-creds-x509,dir=/home/berrange/security/qemutls,endpoint=client,id=tls0 \
    ...other args...

To enable outgoing TLS migration 2 monitor commands are
then used

  (qemu) migrate_set_str_parameter tls-creds tls0
  (qemu) migrate tcp:otherhostname:9000

Thanks to earlier improvements to error reporting,
TLS errors can be seen 'info migrate' when doing a
detached migration. For example:

  (qemu) info migrate
  capabilities: xbzrle: off rdma-pin-all: off auto-converge: off zero-blocks: off compress: off events: off x-postcopy-ram: off
  Migration status: failed
  total time: 0 milliseconds
  error description: TLS handshake failed: The TLS connection was non-properly terminated.

Or

  (qemu) info migrate
  capabilities: xbzrle: off rdma-pin-all: off auto-converge: off zero-blocks: off compress: off events: off x-postcopy-ram: off
  Migration status: failed
  total time: 0 milliseconds
  error description: Certificate does not match the hostname localhost

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-27-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:32:13 +05:30
Daniel P. Berrange
69ef1f36b0 migration: define 'tls-creds' and 'tls-hostname' migration parameters
Define two new migration parameters to be used with TLS encryption.
The 'tls-creds' parameter provides the ID of an instance of the
'tls-creds' object type, or rather a subclass such as 'tls-creds-x509'.
Providing these credentials will enable use of TLS on the migration
data stream.

If using x509 certificates, together with a migration URI that does
not include a hostname, the 'tls-hostname' parameter provides the
hostname to use when verifying the server's x509 certificate. This
allows TLS to be used in combination with fd: and exec: protocols
where a TCP connection is established by a 3rd party outside of
QEMU.

NB, this requires changing the migrate_set_parameter method in the
HMP to accept a 's' (string) value instead of 'i' (integer). This
is backwards compatible, because the parsing of strings allows the
quotes to be optional, thus any integer is also a valid string.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-26-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:32:10 +05:30
Daniel P. Berrange
2594f56d4c migration: don't use an array for storing migrate parameters
The MigrateState struct uses an array for storing migration
parameters. This presumes that all future parameters will
be integers too, which is not going to be the case. There
is no functional reason why an array is used, if anything
it makes the code less clear. The QAPI schema already
defines a struct - MigrationParameters - capable of storing
all the individual parameters, so just use that instead of
an array.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-25-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:32:07 +05:30
Daniel P. Berrange
a24939f279 migration: move definition of struct QEMUFile back into qemu-file.c
Now that the memory buffer based QEMUFile impl is gone, there
is no need for any backend to be accessing internals of the
QEMUFile struct, so it can be moved back into qemu-file.c

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-24-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:32:05 +05:30
Daniel P. Berrange
7fdc61c75d migration: delete QEMUFile stdio implementation
Now that the exec migration backend and savevm have converted
to use the QIOChannel based QEMUFile, there is no user remaining
for the stdio based QEMUFile impl and it can be deleted.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-23-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:32:03 +05:30
Daniel P. Berrange
40946ae40b migration: delete QEMUFile sockets implementation
Now that the tcp, unix and fd migration backends have converted
to use the QIOChannel based QEMUFile, there is no user remaining
for the sockets based QEMUFile impl and it can be deleted.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-22-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:32:00 +05:30
Daniel P. Berrange
2a22b4f370 migration: delete QEMUSizedBuffer struct
Now that we don't have have a buffer based QemuFile
implementation, the QEMUSizedBuffer code is also
unused and can be deleted. A simpler buffer class
also exists in util/buffer.c which other code can
used as needed.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-21-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:31:58 +05:30
Daniel P. Berrange
8b7c5c0f52 migration: delete QEMUFile buffer implementation
The qemu_bufopen() method is no longer used, so the memory
buffer based QEMUFile backend can be deleted entirely.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-20-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:31:55 +05:30
Daniel P. Berrange
8925839f00 migration: convert savevm to use QIOChannel for writing to files
Convert the exec savevm code to use QIOChannel and QEMUFileChannel,
instead of the stdio APIs.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-19-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:31:53 +05:30
Daniel P. Berrange
6ddd2d76ca migration: convert RDMA to use QIOChannel interface
This converts the RDMA code to provide a subclass of QIOChannel
that uses RDMA for the data transport.

This implementation of RDMA does not correctly handle non-blocking
mode. Reads might block if there was not already some pending data
and writes will block until all data is sent. This flawed behaviour
was already present in the existing impl, so appears to not be a
critical problem at this time. It should be on the list of things
to fix in the future though.

The RDMA code would be much better off it it could be split up in
a generic RDMA layer, a QIOChannel impl based on RMDA, and then
the RMDA migration glue. This is left as a future exercise for
the brave.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-18-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:31:50 +05:30
Daniel P. Berrange
527792fae6 migration: convert exec socket protocol to use QIOChannel
Convert the exec socket migration protocol driver to use
QIOChannel and QEMUFileChannel, instead of the stdio
popen APIs. It can be unconditionally built because the
QIOChannelCommand class can report suitable error messages
on platforms which can't fork processes.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-17-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:31:47 +05:30
Daniel P. Berrange
64802ee57f migration: convert fd socket protocol to use QIOChannel
Convert the fd socket migration protocol driver to use
QIOChannel and QEMUFileChannel, instead of plain sockets
APIs. It can be unconditionally built because the
QIOChannel APIs it uses will take care to report suitable
error messages if needed.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-16-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:31:45 +05:30
Daniel P. Berrange
e65c67e4da migration: convert tcp socket protocol to use QIOChannel
Drop the current TCP socket migration driver and extend
the new generic socket driver to cope with the TCP address
format

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-15-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:31:42 +05:30
Daniel P. Berrange
6f860ae755 migration: rename unix.c to socket.c
The unix.c file will be nearly the same as the tcp.c file,
only differing in the initial SocketAddress creation code.
Rename unix.c to socket.c and refactor it a little to
prepare for merging the TCP code.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-14-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:31:40 +05:30
Daniel P. Berrange
d984464eb9 migration: convert unix socket protocol to use QIOChannel
Convert the unix socket migration protocol driver to use
QIOChannel and QEMUFileChannel, instead of plain sockets
APIs. It can be unconditionally built, since the socket
impl of QIOChannel will report a suitable error on platforms
where UNIX sockets are unavailable.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-13-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:31:37 +05:30
Daniel P. Berrange
61b67d473d migration: convert post-copy to use QIOChannelBuffer
The post-copy code does some I/O to/from an intermediate
in-memory buffer rather than direct to the underlying
I/O channel. Switch this code to use QIOChannelBuffer
instead of QEMUSizedBuffer.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-12-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:31:34 +05:30
Daniel P. Berrange
d59ce6f344 migration: add reporting of errors for outgoing migration
Currently if an application initiates an outgoing migration,
it may or may not, get an error reported back on failure. If
the error occurs synchronously to the 'migrate' command
execution, the client app will see the error message. This
is the case for DNS lookup failures. If the error occurs
asynchronously to the monitor command though, the error
will be thrown away and the client left guessing about
what went wrong. This is the case for failure to connect
to the TCP server (eg due to wrong port, or firewall
rules, or other similar errors).

In the future we'll be adding more scope for errors to
happen asynchronously with the TLS protocol handshake.
TLS errors are hard to diagnose even when they are well
reported, so discarding errors entirely will make it
impossible to debug TLS connection problems.

Management apps which do migration are already using
'query-migrate' / 'info migrate' to check up on progress
of background migration operations and to see their end
status. This is a fine place to also include the error
message when things go wrong.

This patch thus adds an 'error-desc' field to the
MigrationInfo struct, which will be populated when
the 'status' is set to 'failed':

(qemu) migrate -d tcp:localhost:9001
(qemu) info migrate
capabilities: xbzrle: off rdma-pin-all: off auto-converge: off zero-blocks: off compress: off events: off x-postcopy-ram: off
Migration status: failed (Error connecting to socket: Connection refused)
total time: 0 milliseconds

In the HMP, when doing non-detached migration, it is
also possible to display this error message directly
to the app.

(qemu) migrate tcp:localhost:9001
Error connecting to socket: Connection refused

Or with QMP

  {
    "execute": "query-migrate",
    "arguments": {}
  }
  {
    "return": {
      "status": "failed",
      "error-desc": "address resolution failed for myhost:9000: No address associated with hostname"
    }
  }

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <1461751518-12128-11-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:31:30 +05:30
Daniel P. Berrange
48f07489ed migration: add helpers for creating QEMUFile from a QIOChannel
Currently creating a QEMUFile instance from a QIOChannel is
quite simple only requiring a single call to
qemu_fopen_channel_input or  qemu_fopen_channel_output
depending on the end of migration connection.

When QEMU gains TLS support, however, there will need to be
a TLS negotiation done inbetween creation of the QIOChannel
and creation of the final QEMUFile. Introduce some helper
methods that will encapsulate this logic, isolating the
migration protocol drivers from knowledge about TLS.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Acked-by: Juan Quintela <quintela@redhat.com>
Message-Id: <1461751518-12128-10-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:31:27 +05:30
Daniel P. Berrange
a9cfeb33bb migration: introduce a new QEMUFile impl based on QIOChannel
Introduce a new QEMUFile implementation that is based on
the QIOChannel objects. This impl is different from existing
impls in that there is no file descriptor that can be made
available, as some channels may be based on higher level
protocols such as TLS.

Although the QIOChannel based implementation can trivially
provide a bi-directional stream, initially we have separate
functions for opening input & output directions to fit with
the expectation of the current QEMUFile interface.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-9-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:31:24 +05:30
Daniel P. Berrange
9e4d2b98ee migration: force QEMUFile to blocking mode for outgoing migration
Instead of relying on the default QEMUFile I/O blocking flag
state, explicitly turn on blocking I/O for outgoing migration
since it takes place in a background thread.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <1461751518-12128-8-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:31:21 +05:30
Daniel P. Berrange
06ad513532 migration: introduce set_blocking function in QEMUFileOps
Remove the assumption that every QEMUFile implementation has
a file descriptor available by introducing a new function
in QEMUFileOps to change the blocking state of a QEMUFile.

If not set, it will fallback to the original code using
the get_fd method.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <1461751518-12128-7-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:31:19 +05:30
Daniel P. Berrange
0436e09f96 migration: split migration hooks out of QEMUFileOps
The QEMUFileOps struct contains the I/O subsystem callbacks
and the migration stage hooks. Split the hooks out into a
separate QEMUFileHooks struct to make it easier to refactor
the I/O side of QEMUFile without affecting the hooks.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <1461751518-12128-6-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:31:16 +05:30
Daniel P. Berrange
baf51e7739 migration: ensure qemu_fflush() always writes full data amount
The QEMUFile writev_buffer / put_buffer functions are expected
to write out the full set of requested data, blocking until
complete. The qemu_fflush() caller does not expect to deal with
partial writes. Clarify the function comments and add a sanity
check to the code to catch mistaken implementations.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <1461751518-12128-5-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-26 11:31:14 +05:30
Kevin Wolf
88be7b4be4 block: Fix bdrv_next() memory leak
The bdrv_next() users all leaked the BdrvNextIterator after completing
the iteration. Simply changing bdrv_next() to free the iterator before
returning NULL at the end of list doesn't work because some callers exit
the loop before looking at all BDSes.

This patch moves the BdrvNextIterator from the heap to the stack of
the caller and switches to a bdrv_first()/bdrv_next() interface for
initialising the iterator.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
2016-05-25 19:04:10 +02:00
Peter Maydell
99694362ee migration fixes:
- ensure src block devices continue fine after a failed migration
 - fail on migration blockers; helps 9p savevm/loadvm
 - move autoconverge commands out of experimental state
 - move the migration-specific qjson in migration/
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2
 
 iQIcBAABCAAGBQJXQzqdAAoJEOsLTfxlfvZwMDgP/0WjJc6tcrRYWPnZ0I4+6/1A
 MByxfBf0LBeST5/A8HDOg8KrTasNHXKisMAQ5kHUxxWLuzF9GYScLdZ2Sf+2VrP2
 rRLJXW2c56cVPsc3j4ZU5t93SO5Q2Dd1hZ2uabu5XMMH2IhtO5H05wfPkkMdRZO2
 XzRt97z0LRBHOvh4O/ZfGjtEaMlmUTpl5X/PpPUW+o6yeDZU00kWFUz7BR7D9q27
 Adru6G8N3pN3KJEMWMqIdmlgoSTEdebTItwLLJ7XwKlKF+bPwr/gsqM6i66C0ahB
 HjpS2T4ly7U33B2JdWElDCZSwlFXAy3Tv7oB0mHgCEqgfryabQXRupVpK0Vyk2EV
 yV7Hf+R/DdkHBNeCCl+rduQiA6ed/DFHSa62vt796Yilf2vUlvdeuh4d1aNp5uxo
 M4QCuxOUsvp75b9mBEuVhz/CCgkq/Hm8HlMZX6/lDTyvNc7qKQnVKWCx95zGsKem
 vPMKxfrKNPY6J08LcjXtqfNNdJEQ5Z1St2a9HiDg5eWuWT2vCgRrjizkMH5zbKEx
 5BJbJlifY1JN7f5+guh9trQRRfB4CTAuuTOLrOH7xbST7jGNaFKAlmzsV0s0xDxF
 /47GcSz5uzLY4T2S4BMSu88mt3gVMTUIaZYxphHvCHqiOMuYG33HHLm8FyAdMBS2
 hhyG4UcKTJtxiO5ymqv5
 =RpPT
 -----END PGP SIGNATURE-----

Merge remote-tracking branch 'remotes/amit-migration/tags/migration-2.7-1' into staging

migration fixes:

- ensure src block devices continue fine after a failed migration
- fail on migration blockers; helps 9p savevm/loadvm
- move autoconverge commands out of experimental state
- move the migration-specific qjson in migration/

# gpg: Signature made Mon 23 May 2016 18:15:09 BST using RSA key ID 657EF670
# gpg: Good signature from "Amit Shah <amit@amitshah.net>"
# gpg:                 aka "Amit Shah <amit@kernel.org>"
# gpg:                 aka "Amit Shah <amitshah@gmx.net>"

* remotes/amit-migration/tags/migration-2.7-1:
  migration: regain control of images when migration fails to complete
  savevm: fail if migration blockers are present
  migration: Promote improved autoconverge commands out of experimental state
  migration/qjson: Drop gratuitous use of QOM
  migration: Move qjson.[ch] to migration/

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-05-24 12:21:07 +01:00
Greg Kurz
fe904ea824 migration: regain control of images when migration fails to complete
We currently have an error path during migration that can cause
the source QEMU to abort:

migration_thread()
  migration_completion()
    runstate_is_running() ----------------> true if guest is running
    bdrv_inactivate_all() ----------------> inactivate images
    qemu_savevm_state_complete_precopy()
     ... qemu_fflush()
           socket_writev_buffer() --------> error because destination fails
         qemu_fflush() -------------------> set error on migration stream
  migration_completion() -----------------> set migrate state to FAILED
migration_thread() -----------------------> break migration loop
  vm_start() -----------------------------> restart guest with inactive
                                            images

and you get:

qemu-system-ppc64: socket_writev_buffer: Got err=104 for (32768/18446744073709551615)
qemu-system-ppc64: /home/greg/Work/qemu/qemu-master/block/io.c:1342:bdrv_co_do_pwritev: Assertion `!(bs->open_flags & 0x0800)' failed.
Aborted (core dumped)

If we try postcopy with a similar scenario, we also get the writev error
message but QEMU leaves the guest paused because entered_postcopy is true.

We could possibly do the same with precopy and leave the guest paused.
But since the historical default for migration errors is to restart the
source, this patch adds a call to bdrv_invalidate_cache_all() instead.

Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Message-Id: <146357896785.6003.11983081732454362715.stgit@bahia.huguette.org>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-23 22:19:36 +05:30
Greg Kurz
24f3902b08 savevm: fail if migration blockers are present
QEMU has currently two ways to prevent migration to occur:
- migration blocker when it depends on runtime state
- VMStateDescription.unmigratable when migration is not supported at all

This patch gathers all the logic into a single function to be called from
both the savevm and the migrate paths.

This fixes a bug with 9p, at least, where savevm would succeed and the
following would happen in the guest after loadvm:

$ ls /host
ls: cannot access /host: Protocol error

With this patch:

(qemu) savevm foo
Migration is disabled when VirtFS export path '/' is mounted in the guest
using mount_tag 'host'

Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <146239057139.11271.9011797645454781543.stgit@bahia.huguette.org>

[Update subject according to Paolo's suggestion - Amit]

Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-23 21:44:08 +05:30
Gonglei
fa53a0e53e memory: drop find_ram_block()
On the one hand, we have already qemu_get_ram_block() whose function
is similar. On the other hand, we can directly use mr->ram_block but
searching RAMblock by ram_addr which is a kind of waste.

Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-Id: <1462845901-89716-2-git-send-email-arei.gonglei@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-23 16:53:44 +02:00
Jason J. Herne
d85a31d1f4 migration: Promote improved autoconverge commands out of experimental state
The new autoconverge throttling commands have been tested for a release now. It
is time to move them out of the experimental state.

Signed-off-by: Jason J. Herne <jjherne@linux.vnet.ibm.com>
Message-Id: <1461262038-8197-1-git-send-email-jjherne@linux.vnet.ibm.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-23 16:05:09 +05:30
Markus Armbruster
b72fe9e690 migration/qjson: Drop gratuitous use of QOM
All the use of QOM buys us here is the ability to destroy the thing
with object_unref(OBJECT(vmdesc)).  Not worth the notational overhead.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <1462380558-2030-3-git-send-email-armbru@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-23 14:16:12 +05:30
Markus Armbruster
17b74b9867 migration: Move qjson.[ch] to migration/
Type QJSON lets you build JSON text.  Its interface mirrors (a subset
of) abstract JSON syntax.

QAPI output visitors also produce JSON text.  They assert their
preconditions and invariants, and therefore abort on incorrect use.

Contrastingly, QJSON does *not* detect incorrect use.  It happily
produces invalid JSON then.  This is what migration wants.

QJSON was designed for migration, and migration is its only user.
Move it to migration/ for proper coverage by MAINTAINERS, and to deter
accidental use outside migration.

[Pointed out by Eric: QJSON was added in commits 0457d07..b174257
 -- Amit]

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <1462380558-2030-2-git-send-email-armbru@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-05-23 14:16:09 +05:30