Commit Graph

284 Commits

Author SHA1 Message Date
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.
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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/
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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
Peter Maydell 6bd8ab6889 Block layer patches
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Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging

Block layer patches

# gpg: Signature made Thu 19 May 2016 16:09:27 BST using RSA key ID C88F2FD6
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>"

* remotes/kevin/tags/for-upstream: (31 commits)
  qemu-iotests: Fix regression in 136 on aio_read invalid
  qemu-iotests: Simplify 109 with unaligned qemu-img compare
  qemu-io: Fix recent UI updates
  block: clarify error message for qmp-eject
  qemu-iotests: Some more write_zeroes tests
  qcow2: Fix write_zeroes with partially allocated backing file cluster
  qcow2: fix condition in is_zero_cluster
  block: Propagate AioContext change to all children
  block: Remove BlockDriverState.blk
  block: Don't return throttling info in query-named-block-nodes
  block: Avoid bs->blk in bdrv_next()
  block: Add bdrv_has_blk()
  block: Remove bdrv_aio_multiwrite()
  blockjob: Don't touch BDS iostatus
  blockjob: Don't set iostatus of target
  block: User BdrvChild callback for device name
  block: Use BdrvChild callbacks for change_media/resize
  block: Don't check throttled reqs in bdrv_requests_pending()
  Revert "block: Forbid I/O throttling on nodes with multiple parents for 2.6"
  block: Remove bdrv_move_feature_fields()
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-05-19 16:54:12 +01:00
Kevin Wolf 7c8eece45b block: Avoid bs->blk in bdrv_next()
We need to introduce a separate BdrvNextIterator struct that can keep
more state than just the current BDS in order to avoid using the bs->blk
pointer.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-05-19 16:45:31 +02:00
Paolo Bonzini 33c11879fd qemu-common: push cpu.h inclusion out of qemu-common.h
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-19 16:42:29 +02:00
Stefan Weil cb8d4c8f54 Fix some typos found by codespell
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2016-05-18 15:04:27 +03:00
Veronia Bahaa f348b6d1a5 util: move declarations out of qemu-common.h
Move declarations out of qemu-common.h for functions declared in
utils/ files: e.g. include/qemu/path.h for utils/path.c.
Move inline functions out of qemu-common.h and into new files (e.g.
include/qemu/bcd.h)

Signed-off-by: Veronia Bahaa <veroniabahaa@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22 22:20:17 +01:00
Markus Armbruster da34e65cb4 include/qemu/osdep.h: Don't include qapi/error.h
Commit 57cb38b included qapi/error.h into qemu/osdep.h to get the
Error typedef.  Since then, we've moved to include qemu/osdep.h
everywhere.  Its file comment explains: "To avoid getting into
possible circular include dependencies, this file should not include
any other QEMU headers, with the exceptions of config-host.h,
compiler.h, os-posix.h and os-win32.h, all of which are doing a
similar job to this file and are under similar constraints."
qapi/error.h doesn't do a similar job, and it doesn't adhere to
similar constraints: it includes qapi-types.h.  That's in excess of
100KiB of crap most .c files don't actually need.

Add the typedef to qemu/typedefs.h, and include that instead of
qapi/error.h.  Include qapi/error.h in .c files that need it and don't
get it now.  Include qapi-types.h in qom/object.h for uint16List.

Update scripts/clean-includes accordingly.  Update it further to match
reality: replace config.h by config-target.h, add sysemu/os-posix.h,
sysemu/os-win32.h.  Update the list of includes in the qemu/osdep.h
comment quoted above similarly.

This reduces the number of objects depending on qapi/error.h from "all
of them" to less than a third.  Unfortunately, the number depending on
qapi-types.h shrinks only a little.  More work is needed for that one.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
[Fix compilation without the spice devel packages. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22 22:20:15 +01:00
Peter Maydell 0dcee62261 migration:
- postcopy is no longer experimental
  - fix a use-after-free in postcopy
  - fix a compile warning
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Merge remote-tracking branch 'remotes/amit-migration/tags/migration-for-2.6-7' into staging

migration:
 - postcopy is no longer experimental
 - fix a use-after-free in postcopy
 - fix a compile warning

# gpg: Signature made Fri 11 Mar 2016 12:29:33 GMT using RSA key ID 854083B6
# 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-for-2.6-7:
  postcopy: Remove the x-
  postcopy: listen thread is never joined
  migration: fix use-after-free in loadvm_postcopy_handle_run_bh
  migration: fix warning for source_return_path_thread

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-03-14 13:51:21 +00:00
Dr. David Alan Gilbert 32c3db5b26 postcopy: Remove the x-
Postcopy seems to have survived a cycle with only a few fixes,
and Jiri has the current libvirt wired up and working
( https://www.redhat.com/archives/libvir-list/2016-March/msg00080.html )
so remove the experimental tag.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1457690016-9070-3-git-send-email-dgilbert@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-03-11 17:53:59 +05:30
Dr. David Alan Gilbert a587a3fe6c postcopy: listen thread is never joined
We don't join the listen thread, it does its own cleanup.
Mark as detached not joinable.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reported-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1457690016-9070-2-git-send-email-dgilbert@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-03-11 17:53:59 +05:30
Denis V. Lunev 8646992279 migration: fix use-after-free in loadvm_postcopy_handle_run_bh
MigrationState is destroyed before we can come into bottom half.

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>
CC: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <1457537708-8622-1-git-send-email-den@openvz.org>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-03-11 12:58:45 +05:30
Peter Xu 568b01caf3 migration: fix warning for source_return_path_thread
max_len is not necessary, while it brings a warning during compilation
when specify "-Wstack-usage=1000000". Replacing using sizeof().

Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <1457503932-31763-1-git-send-email-peterx@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-03-11 12:58:37 +05:30
Daniel P. Berrange b16a44e13e osdep: remove use of socket_error() from all code
Now that QEMU wraps the Win32 sockets methods to automatically
set errno upon failure, there is no reason for callers to use
the socket_error() method. They can rely on accessing errno
even on Win32. Remove all use of socket_error() from general
code, leaving it as a static method in oslib-win32.c only.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-03-10 17:19:34 +00:00
Dr. David Alan Gilbert 614e8018ed Postcopy: Fix sync count in info migrate
I'd missed the sync count off in the postcopy case.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Message-id: 1456394631-18010-1-git-send-email-dgilbert@redhat.com
Message-Id: <1456394631-18010-1-git-send-email-dgilbert@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-03-08 16:52:27 +05:30
Greg Kurz 902c053d83 migration: allow machine to enforce configuration section migration
Migration of pseries-2.3 doesn't have configuration section. Unfortunately,
QEMU 2.4/2.4.1/2.5 are buggy and always stream and expect the configuration
section, and break migration both ways.

This patch introduces a property which allows to enforce a configuration
section for machines who don't have one.

It can be set at startup:

-machine enforce-config-section=on

or later from the QEMU monitor:

qom-set /machine enforce-config-section on

It is up to the tooling to set or unset this property according to the
version of the QEMU at the other end of the pipe.

Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-02-28 16:19:02 +11:00
Denis V. Lunev ea6a55bcc0 migration (postcopy): move bdrv_invalidate_cache_all of of coroutine context
There is a possibility to hit an assert in qcow2_get_specific_info that
s->qcow_version is undefined. This happens when VM in starting from
suspended state, i.e. it processes incoming migration, and in the same
time 'info block' is called.

The problem is that qcow2_invalidate_cache() closes the image and
memset()s BDRVQcowState in the middle.

The patch moves processing of bdrv_invalidate_cache_all out of
coroutine context for postcopy migration to avoid that. This function
is called with the following stack:
  process_incoming_migration_co
  qemu_loadvm_state
  qemu_loadvm_state_main
  loadvm_process_command
  loadvm_postcopy_handle_run

Signed-off-by: Denis V. Lunev <den@openvz.org>
Tested-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Juan Quintela <quintela@redhat.com>
CC: Amit Shah <amit.shah@redhat.com>
Message-Id: <1456304019-10507-3-git-send-email-den@openvz.org>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-02-26 20:40:08 +05:30