Commit Graph

248 Commits

Author SHA1 Message Date
Kashyap Chamarthy
a910523a24 qmp-commands.hx: Update the supported 'transaction' operations
Although the canonical source of reference for QMP commands is
qapi-schema.json, for consistency's sake, update qmp-commands.hx to
state the list of supported transactionable operations, namely:

    drive-backup
    blockdev-backup
    blockdev-snapshot-internal-sync
    abort
    block-dirty-bitmap-add
    block-dirty-bitmap-clear

Also update the possible values for the "type" action array.

Signed-off-by: Kashyap Chamarthy <kchamart@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-10-16 15:34:29 +02:00
Daniel P. Berrange
6287d827d4 monitor: allow device_del to accept QOM paths
Currently device_del requires that the client provide the
device short ID. device_add allows devices to be created
without giving an ID, at which point there is no way to
delete them with device_del. The QOM object path, however,
provides an alternative way to identify the devices.

Allowing device_del to accept an object path ensures all
devices are deletable regardless of whether they have an
ID.

 (qemu) device_add usb-mouse
 (qemu) qom-list /machine/peripheral-anon
 device[0] (child<usb-mouse>)
 type (string)
 (qemu) device_del /machine/peripheral-anon/device[0]

Devices are required to be marked as hotpluggable
otherwise an error is raised

 (qemu) device_del /machine/unattached/device[4]
 Device 'PIIX3' does not support hotplugging

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1441974836-17476-1-git-send-email-berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[Commit message touched up, accidental white-space change dropped]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-09-22 11:31:56 +02:00
Markus Armbruster
39a1815816 qapi: New QMP command query-qmp-schema for QMP introspection
qapi/introspect.json defines the introspection schema.  It's designed
for QMP introspection, but should do for similar uses, such as QGA.

The introspection schema does not reflect all the rules and
restrictions that apply to QAPI schemata.  A valid QAPI schema has an
introspection value conforming to the introspection schema, but the
converse is not true.

Introspection lowers away a number of schema details, and makes
implicit things explicit:

* The built-in types are declared with their JSON type.

  All integer types are mapped to 'int', because how many bits we use
  internally is an implementation detail.  It could be pressed into
  external interface service as very approximate range information,
  but that's a bad idea.  If we need range information, we better do
  it properly.

* Implicit type definitions are made explicit, and given
  auto-generated names:

  - Array types, named by appending "List" to the name of their
    element type, like in generated C.

  - The enumeration types implicitly defined by simple union types,
    named by appending "Kind" to the name of their simple union type,
    like in generated C.

  - Types that don't occur in generated C.  Their names start with ':'
    so they don't clash with the user's names.

* All type references are by name.

* The struct and union types are generalized into an object type.

* Base types are flattened.

* Commands take a single argument and return a single result.

  Dictionary argument or list result is an implicit type definition.

  The empty object type is used when a command takes no arguments or
  produces no results.

  The argument is always of object type, but the introspection schema
  doesn't reflect that.

  The 'gen': false directive is omitted as implementation detail.

  The 'success-response' directive is omitted as well for now, even
  though it's not an implementation detail, because it's not used by
  QMP.

* Events carry a single data value.

  Implicit type definition and empty object type use, just like for
  commands.

  The value is of object type, but the introspection schema doesn't
  reflect that.

* Types not used by commands or events are omitted.

  Indirect use counts as use.

* Optional members have a default, which can only be null right now

  Instead of a mandatory "optional" flag, we have an optional default.
  No default means mandatory, default null means optional without
  default value.  Non-null is available for optional with default
  (possible future extension).

* Clients should *not* look up types by name, because type names are
  not ABI.  Look up the command or event you're interested in, then
  follow the references.

  TODO Should we hide the type names to eliminate the temptation?

New generator scripts/qapi-introspect.py computes an introspection
value for its input, and generates a C variable holding it.

It can generate awfully long lines.  Marked TODO.

A new test-qmp-input-visitor test case feeds its result for both
tests/qapi-schema/qapi-schema-test.json and qapi-schema.json to a
QmpInputVisitor to verify it actually conforms to the schema.

New QMP command query-qmp-schema takes its return value from that
variable.  Its reply is some 85KiBytes for me right now.

If this turns out to be too much, we have a couple of options:

* We can use shorter names in the JSON.  Not the QMP style.

* Optionally return the sub-schema for commands and events given as
  arguments.

  Right now qmp_query_schema() sends the string literal computed by
  qmp-introspect.py.  To compute sub-schema at run time, we'd have to
  duplicate parts of qapi-introspect.py in C.  Unattractive.

* Let clients cache the output of query-qmp-schema.

  It changes only on QEMU upgrades, i.e. rarely.  Provide a command
  query-qmp-schema-hash.  Clients can have a cache indexed by hash,
  and re-query the schema only when they don't have it cached.  Even
  simpler: put the hash in the QMP greeting.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-09-21 09:56:49 +02:00
Markus Armbruster
b8a98326d5 qapi-schema: Fix up misleading specification of netdev_add
It doesn't take a 'props' argument, let alone one in the format
"NAME=VALUE,..."

The bogus arguments specification doesn't matter due to 'gen': false.
Clean it up to be incomplete rather than wrong, and document the
incompleteness.

While there, improve netdev_add usage example in the manual: add a
device option to show how it's done.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1442401589-24189-24-git-send-email-armbru@redhat.com>
2015-09-21 09:56:49 +02:00
Markus Armbruster
6eb3937e9b qom: Don't use 'gen': false for qom-get, qom-set, object-add
With the previous commit, the generated marshalers just work, and save
us a bit of handwritten code.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1442401589-24189-23-git-send-email-armbru@redhat.com>
2015-09-21 09:56:49 +02:00
Markus Armbruster
7fad30f06e qapi: Rename qmp_marshal_input_FOO() to qmp_marshal_FOO()
These functions marshal both input and output.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1442401589-24189-17-git-send-email-armbru@redhat.com>
2015-09-21 09:56:48 +02:00
Jason J. Herne
7ee0c3e33a s390x: Dump storage keys qmp command
Provide a dump-skeys qmp command to allow the end user to dump storage
keys. This is useful for debugging problems with guest storage key support
within Qemu and for guest operating system developers.

Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Jason J. Herne <jjherne@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-09-03 12:17:54 +02:00
Juan Quintela
72e72e1a71 migration: Write documetation for events capabilites
Reported-by: Jiri Denemark <jdenemar@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-07-15 09:07:54 +02:00
Fam Zheng
0fc9f8ea28 qmp: Add optional bool "unmap" to drive-mirror
If specified as "true", it allows discarding on target sectors where source is
not allocated.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-07-02 10:06:23 +01:00
John Snow
4b80ab2b7d qapi: Rename 'dirty-bitmap' mode to 'incremental'
If we wish to make differential backups a feature that's easy to access,
it might be pertinent to rename the "dirty-bitmap" mode to "incremental"
to make it clear what /type/ of backup the dirty-bitmap is helping us
perform.

This is an API breaking change, but 2.4 has not yet gone live,
so we have this flexibility.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 1433463642-21840-2-git-send-email-jsnow@redhat.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-07-02 09:20:18 +01:00
Dr. David Alan Gilbert
4aab6282f8 Grammar: 'as to'->'as for'
Fixup migrate-incoming text as requested by Eric in:

 http://lists.nongnu.org/archive/html/qemu-devel/2015-03/msg03362.html

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-06-23 19:57:27 +03:00
Markus Armbruster
485febc6d1 qmp: Wean off qerror_report()
The traditional QMP command handler interface

    int qmp_FOO(Monitor *mon, const QDict *params, QObject **ret_data);

doesn't provide for returning an Error object.  Instead, the handler
is expected to stash it in the monitor with qerror_report().

When we rebased QMP on top of QAPI, we didn't change this interface.
Instead, commit 776574d introduced "middle mode" as a temporary aid
for converting existing QMP commands to QAPI one by one.  More than
three years later, we're still using it.

Middle mode has two effects:

* Instead of the native input marshallers

      static void qmp_marshal_input_FOO(QDict *, QObject **, Error **)

  it generates input marshallers conforming to the traditional QMP
  command handler interface.

* It suppresses generation of code to register them with
  qmp_register_command()

  This permits giving them internal linkage.

As long as we need qmp-commands.hx, we can't use the registry behind
qmp_register_command(), so the latter has to stay for now.

The former has to go to get rid of qerror_report().  Changing all QMP
commands to fit the QAPI mold in one go was impractical back when we
started, but by now there are just a few stragglers left:
do_qmp_capabilities(), qmp_qom_set(), qmp_qom_get(), qmp_object_add(),
qmp_netdev_add(), do_device_add().

Switch middle mode to generate native input marshallers, and adapt the
stragglers.  Simplifies both the monitor code and the stragglers.

Rename do_qmp_capabilities() to qmp_capabilities(), and
do_device_add() to qmp_device_add, because that's how QMP command
handlers are named today.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
2015-06-22 18:20:40 +02:00
Peter Maydell
8aeaa055f5 -----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
 
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 =mx5x
 -----END PGP SIGNATURE-----

Merge remote-tracking branch 'remotes/stefanha/tags/block-pull-request' into staging

# gpg: Signature made Fri Jun 12 15:57:47 2015 BST using RSA key ID 81AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>"
# gpg:                 aka "Stefan Hajnoczi <stefanha@gmail.com>"

* remotes/stefanha/tags/block-pull-request:
  qemu-iotests: expand test 093 to support group throttling
  throttle: Update throttle infrastructure copyright
  throttle: add the name of the ThrottleGroup to BlockDeviceInfo
  throttle: acquire the ThrottleGroup lock in bdrv_swap()
  throttle: Add throttle group support
  throttle: Add throttle group infrastructure tests
  throttle: Add throttle group infrastructure
  throttle: Extract timers from ThrottleState into a separate structure
  raw-posix: Fix .bdrv_co_get_block_status() for unaligned image size
  Revert "iothread: release iothread around aio_poll"

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-06-12 18:04:14 +01:00
Alberto Garcia
76f4afb40f throttle: Add throttle group support
The throttle group support use a cooperative round robin scheduling
algorithm.

The principles of the algorithm are simple:
- Each BDS of the group is used as a token in a circular way.
- The active BDS computes if a wait must be done and arms the right
  timer.
- If a wait must be done the token timer will be armed so the token
  will become the next active BDS.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: f0082a86f3ac01c46170f7eafe2101a92e8fde39.1433779731.git.berto@igalia.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-06-12 14:00:00 +01:00
Scott Feldman
fafa4d508b qmp/hmp: add rocker device support
Add QMP/HMP support for rocker devices.  This is mostly for debugging purposes
to see inside the device's tables and port configurations.  Some examples:

(qemu) info rocker sw1
name: sw1
id: 0x0000013512005452
ports: 4

(qemu) info rocker-ports sw1
            ena/    speed/ auto
      port  link    duplex neg?
     sw1.1  up     10G  FD  No
     sw1.2  up     10G  FD  No
     sw1.3  !ena   10G  FD  No
     sw1.4  !ena   10G  FD  No

(qemu) info rocker-of-dpa-flows sw1
prio tbl hits key(mask) --> actions
2    60       pport 1 vlan 1 LLDP src 00:02:00:00:02:00 dst 01:80:c2:00:00:0e
2    60       pport 1 vlan 1 ARP src 00:02:00:00:02:00 dst 00:02:00:00:03:00
2    60       pport 2 vlan 2 IPv6 src 00:02:00:00:03:00 dst 33:33:ff:00:00:02 proto 58
3    50       vlan 2 dst 33:33:ff:00:00:02 --> write group 0x32000001 goto tbl 60
2    60       pport 2 vlan 2 IPv6 src 00:02:00:00:03:00 dst 33:33:ff:00:03:00 proto 58
3    50  1    vlan 2 dst 33:33:ff:00:03:00 --> write group 0x32000001 goto tbl 60
2    60       pport 2 vlan 2 ARP src 00:02:00:00:03:00 dst 00:02:00:00:02:00
3    50  2    vlan 2 dst 00:02:00:00:02:00 --> write group 0x02000001 goto tbl 60
2    60  1    pport 2 vlan 2 IP src 00:02:00:00:03:00 dst 00:02:00:00:02:00 proto 1
3    50  2    vlan 1 dst 00:02:00:00:03:00 --> write group 0x01000002 goto tbl 60
2    60  1    pport 1 vlan 1 IP src 00:02:00:00:02:00 dst 00:02:00:00:03:00 proto 1
2    60       pport 1 vlan 1 IPv6 src 00:02:00:00:02:00 dst 33:33:ff:00:00:01 proto 58
3    50       vlan 1 dst 33:33:ff:00:00:01 --> write group 0x31000000 goto tbl 60
2    60       pport 1 vlan 1 IPv6 src 00:02:00:00:02:00 dst 33:33:ff:00:02:00 proto 58
3    50  1    vlan 1 dst 33:33:ff:00:02:00 --> write group 0x31000000 goto tbl 60
1    60  173  pport 2 vlan 2 LLDP src <any> dst 01:80:c2:00:00:0e --> write group 0x02000000
1    60  6    pport 2 vlan 2 IPv6 src <any> dst <any> --> write group 0x02000000
1    60  174  pport 1 vlan 1 LLDP src <any> dst 01:80:c2:00:00:0e --> write group 0x01000000
1    60  174  pport 2 vlan 2 IP src <any> dst <any> --> write group 0x02000000
1    60  6    pport 1 vlan 1 IPv6 src <any> dst <any> --> write group 0x01000000
1    60  181  pport 2 vlan 2 ARP src <any> dst <any> --> write group 0x02000000
1    10  715  pport 2 --> apply new vlan 2 goto tbl 20
1    60  177  pport 1 vlan 1 ARP src <any> dst <any> --> write group 0x01000000
1    60  174  pport 1 vlan 1 IP src <any> dst <any> --> write group 0x01000000
1    10  717  pport 1 --> apply new vlan 1 goto tbl 20
1    0   1432 pport 0(0xffff) --> goto tbl 10

(qemu) info rocker-of-dpa-groups sw1
id (decode) --> buckets
0x32000001 (type L2 multicast vlan 2 index 1) --> groups [0x02000001,0x02000000]
0x02000001 (type L2 interface vlan 2 pport 1) --> pop vlan out pport 1
0x01000002 (type L2 interface vlan 1 pport 2) --> pop vlan out pport 2
0x02000000 (type L2 interface vlan 2 pport 0) --> pop vlan out pport 0
0x01000000 (type L2 interface vlan 1 pport 0) --> pop vlan out pport 0
0x31000000 (type L2 multicast vlan 1 index 0) --> groups [0x01000002,0x01000000]

[Added "query-" prefixes to rocker.json commands as suggested by Eric
Blake <eblake@redhat.com>.
--Stefan]

Signed-off-by: Scott Feldman <sfeldma@gmail.com>
Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Message-id: 1433985681-56138-5-git-send-email-sfeldma@gmail.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-06-12 13:42:17 +01:00
Markus Armbruster
b8a185bc9a monitor: Convert client_migrate_info to QAPI
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
2015-06-02 09:59:13 +02:00
Markus Armbruster
13cadefbda monitor: Improve and document client_migrate_info protocol error
Protocol must be spice, vnc isn't implemented.  Fix up documentation.

Attempts to use vnc or any other unknown protocol yield the misleading
error message "Invalid parameter 'protocol'".  Improve it to
"Parameter 'protocol' expects spice".

Cc: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by. Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
2015-06-02 09:59:13 +02:00
Eduardo Habkost
58f88d4b7e qmp: Add qom_path field to query-cpus command
This will allow clients to query additional information directly using
qom-get on the CPU objects.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-05-14 17:25:46 +02:00
Liang Li
85de83231e migration: Add qmp commands to set and query parameters
Add the qmp commands to tune and query the parameters used in live
migration.

Signed-off-by: Liang Li <liang.z.li@intel.com>
Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-05-07 18:31:53 +02:00
John Snow
5403432f39 qmp-commands: Fix typo
Just a trivial patch to correct a QMP example in qmp-commands.hx.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-04-30 16:06:17 +03:00
John Snow
e74e6b78e6 qmp: add block-dirty-bitmap-clear
Add bdrv_clear_dirty_bitmap and a matching QMP command,
qmp_block_dirty_bitmap_clear that enables a user to reset
the bitmap attached to a drive.

This allows us to reset a bitmap in the event of a full
drive backup.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1429314609-29776-12-git-send-email-jsnow@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-04-28 15:36:10 +02:00
John Snow
d58d845397 qmp: Add support of "dirty-bitmap" sync mode for drive-backup
For "dirty-bitmap" sync mode, the block job will iterate through the
given dirty bitmap to decide if a sector needs backup (backup all the
dirty clusters and skip clean ones), just as allocation conditions of
"top" sync mode.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1429314609-29776-11-git-send-email-jsnow@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-04-28 15:36:10 +02:00
John Snow
341ebc2f81 qmp: Add block-dirty-bitmap-add and block-dirty-bitmap-remove
The new command pair is added to manage a user created dirty bitmap. The
dirty bitmap's name is mandatory and must be unique for the same device,
but different devices can have bitmaps with the same names.

The granularity is an optional field. If it is not specified, we will
choose a default granularity based on the cluster size if available,
clamped to between 4K and 64K to mirror how the 'mirror' code was
already choosing granularity. If we do not have cluster size info
available, we choose 64K. This code has been factored out into a helper
shared with block/mirror.

This patch also introduces the 'block_dirty_bitmap_lookup' helper,
which takes a device name and a dirty bitmap name and validates the
lookup, returning NULL and setting errp if there is a problem with
either field. This helper will be re-used in future patches in this
series.

The types added to block-core.json will be re-used in future patches
in this series, see:
'qapi: Add transaction support to block-dirty-bitmap-{add, enable, disable}'

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1429314609-29776-5-git-send-email-jsnow@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-04-28 15:36:10 +02:00
Stefan Hajnoczi
ec683d6040 block: document block-stream in qmp-commands.hx
The 'block-stream' QMP command is documented in block-core.json but not
qmp-commands.hx.  Add a summary of the command to qmp-commands.hx
(similar to the documentation for 'block-commit').

Reported-by: Kashyap Chamarthy <kchamart@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 1429094622-26218-1-git-send-email-stefanha@redhat.com
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-04-28 15:36:09 +02:00
Peter Maydell
3d27b09cf6 spice: misc fixes.
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Merge remote-tracking branch 'remotes/spice/tags/pull-spice-20150427-1' into staging

spice: misc fixes.

# gpg: Signature made Mon Apr 27 12:03:16 2015 BST using RSA key ID D3E87138
# gpg: Good signature from "Gerd Hoffmann (work) <kraxel@redhat.com>"
# gpg:                 aka "Gerd Hoffmann <gerd@kraxel.org>"
# gpg:                 aka "Gerd Hoffmann (private) <kraxel@gmail.com>"

* remotes/spice/tags/pull-spice-20150427-1:
  spice: learn to hide cursor
  spice: set pointer position on hotspot
  spice: fix mouse cursor position
  spice: fix simple display on bigendian hosts
  monitor: Make client_migrate_info synchronous

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-04-27 20:00:57 +01:00
Markus Armbruster
3b5704b2f8 monitor: Make client_migrate_info synchronous
Live migration with spice works like this today:

  (1) client_migrate_info monitor cmd
  (2) spice server notifies client, client connects to target host.
  (3) qemu waits until spice client connect is finished.
  (4) send over vmstate (i.e. main part of live migration).
  (5) spice handover to target host.

(3) is implemented by making client_migrate_info a async monitor
command.  This is the only async monitor command we have.

The original reason to implement this dance was that qemu did not accept
new tcp connections while the incoming migration was running, so (2) and
(4) could not be done in parallel.  That issue was fixed long ago though.
Qemu version 1.3.0 (released Dec 2012) and newer happily accept tcp
connects while the incoming migration runs.

Time to drop step (3).  This patch does exactly that, by making the
monitor command synchronous and removing the code needed to handle the
async monitor command in ui/spice-core.c

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2015-04-27 12:46:57 +02:00
Paolo Bonzini
43d0a2c1af qmp-commands: fix incorrect uses of ":O" specifier
As far as the QMP parser is concerned, neither the 'O' nor the 'q' format specifiers
put any constraint on the command.  However, there are two differences:

1) from a documentation point of view 'O' says that this command takes
a dictionary.  The dictionary will be converted to QemuOpts in the
handler to match the corresponding HMP command.

2) 'O' sets QMP_ACCEPT_UNKNOWNS, resulting in the command accepting invalid
extra arguments.  For example the following is accepted:

   { "execute": "send-key",
        "arguments": { "keys": [ { "type": "qcode", "data": "ctrl" },
                                 { "type": "qcode", "data": "alt" },
                                 { "type": "qcode", "data": "delete" } ], "foo": "bar" } }

Neither send-key nor migrate-set-capabilities take a QemuOpts-like
dictionary; they take an array of dictionaries.  And neither command
really wants to have extra unknown arguments.  Thus, the right
specifier to use in this case is 'q'; with this patch the above
command fails with

   {"error": {"class": "GenericError", "desc": "Invalid parameter 'foo'"}}

as intended.

Reported-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2015-04-24 14:18:06 -04:00
Markus Armbruster
da2cf4e803 block: Document blockdev-add's immaturity
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1426858337-21423-1-git-send-email-armbru@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-03-27 10:01:12 +00:00
Peter Maydell
3e5f6234b4 Block patches for 2.3.0-rc1
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Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging

Block patches for 2.3.0-rc1

# gpg: Signature made Thu Mar 19 15:03:26 2015 GMT using RSA key ID C88F2FD6
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>"

* remotes/kevin/tags/for-upstream:
  block: Fix blockdev-backup not to use funky error class
  raw-posix: Deprecate aio=threads fallback without O_DIRECT
  raw-posix: Deprecate host floppy passthrough

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-03-19 17:47:08 +00:00
Markus Armbruster
92a539d22e raw-posix: Deprecate host floppy passthrough
Raise your hand if you have a physical floppy drive in a computer
you've powered on in 2015.  Okay, I see we got a few weirdos in the
audience.  That's okay, weirdos are welcome here.

Kidding aside, media change detection doesn't fully work, isn't going
to be fixed, and floppy passthrough just isn't earning its keep
anymore.

Deprecate block driver host_floppy now, so we can drop it after a
grace period.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-03-19 11:43:02 +01:00
Markus Armbruster
293811f6c1 qmp: Drop unused .user_print from command definitions
.user_print isn't used with QMP commands, only with HMP commands.
Copied over when QMP got its own command table in commit 82a56f0.
Most of them have been dropped since, but a few stragglers remain.
Drop them.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-03-19 11:11:55 +03:00
Dr. David Alan Gilbert
bf1ae1f4dc Add migrate_incoming
Add migrate_incoming/migrate-incoming to start an incoming
migration.

Once a qemu has been started with
    -incoming defer

the migration can be started by issuing:
    migrate_incoming uri

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-03-16 14:31:07 +01:00
Alberto Garcia
3599d46ba2 qmp-commands.hx: Fix several typos
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-03-10 08:15:33 +03:00
Francesco Romani
e2462113b2 block: add event when disk usage exceeds threshold
Managing applications, like oVirt (http://www.ovirt.org), make extensive
use of thin-provisioned disk images.
To let the guest run smoothly and be not unnecessarily paused, oVirt sets
a disk usage threshold (so called 'high water mark') based on the occupation
of the device,  and automatically extends the image once the threshold
is reached or exceeded.

In order to detect the crossing of the threshold, oVirt has no choice but
aggressively polling the QEMU monitor using the query-blockstats command.
This lead to unnecessary system load, and is made even worse under scale:
deployments with hundreds of VMs are no longer rare.

To fix this, this patch adds:
* A new monitor command `block-set-write-threshold', to set a mark for
  a given block device.
* A new event `BLOCK_WRITE_THRESHOLD', to report if a block device
  usage exceeds the threshold.
* A new `write_threshold' field into the `BlockDeviceInfo' structure,
  to report the configured threshold.

This will allow the managing application to use smarter and more
efficient monitoring, greatly reducing the need of polling.

[Updated qemu-iotests 067 output to add the new 'write_threshold'
property. --Stefan]
[Changed g_assert_false() to !g_assert() to fix the build on older glib
versions. --Kevin]

Signed-off-by: Francesco Romani <fromani@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1421068273-692-1-git-send-email-fromani@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-02-06 17:24:21 +01:00
Peter Lieven
f4564d53c6 block: add accounting for merged requests
Signed-off-by: Peter Lieven <pl@kamp.de>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-02-06 17:24:21 +01:00
Gerd Hoffmann
df88768460 monitor: add query-vnc-servers command
Add new query vnc qmp command, for the lack of better ideas just name it
"query-vnc-servers".  Changes over query-vnc:

 * It returns a list of vnc servers, so multiple vnc server instances
   are covered.
 * Each vnc server returns a list of server sockets.  Followup patch
   will use that to also report websockets.  In case we add support for
   multiple server sockets server sockets (to better support ipv4+ipv6
   dualstack) we can add them to the list too.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2015-01-22 11:18:47 +01:00
Fam Zheng
c29c1dd312 qmp: Add command 'blockdev-backup'
Similar to drive-backup, but this command uses a device id as target
instead of creating/opening an image file.

Also add blocker on target bs, since the target is also a named device
now.

Add check and report error for bs == target which became possible but is
an illegal case with introduction of blockdev-backup.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-id: 1418899027-8445-3-git-send-email-famz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2015-01-13 11:47:56 +00:00
zhanghailiang
d6d69731f5 qmp-command.hx: add missing docs for migration capabilites
Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2014-12-16 17:47:35 +05:30
Peter Maydell
99c9c3cb24 trivial patches for 2014-12-11
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Merge remote-tracking branch 'remotes/mjt/tags/pull-trivial-patches-2014-12-11' into staging

trivial patches for 2014-12-11

# gpg: Signature made Thu 11 Dec 2014 18:13:58 GMT using RSA key ID A4C3D7DB
# gpg: Good signature from "Michael Tokarev <mjt@tls.msk.ru>"
# gpg:                 aka "Michael Tokarev <mjt@corpit.ru>"
# gpg:                 aka "Michael Tokarev <mjt@debian.org>"

* remotes/mjt/tags/pull-trivial-patches-2014-12-11:
  Sort include/qemu/typedefs.h
  hpet: increase spelling precision
  pflash_cfi02.c: associate "cfi.pflash02" to "Storage devices" category
  vt82c686: fix coverity warning about out-of-bounds write
  virtio: remove useless declaration of virtio_net_init()
  qapi-schema: fix typo about change-vnc-password
  fw_cfg: remove superfluous blank line
  get_maintainer.pl: Remove the --git-chief-penguins option
  configure: Replace which(1) with "has"
  util: Use g_new() & friends where that makes obvious sense
  util: Fuse g_malloc(); memset() into g_new0()
  util: Drop superfluous conditionals around g_free()
  Drop superfluous conditionals around g_strdup()
  Drop superfluous conditionals around qemu_opts_del()
  usb: delete redundant brackets in usb_host_handle_control()
  virtio-bus: avoid breaking build when open DEBUG switch
  acpi-build: Make DPRINTF working for acpi-build
  acpi-build: adjust indention 8 -> 4 spaces
  target-s390x: fix possible out of bounds read
  qmp: fix typo in input-send-event examples

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-12-11 18:27:02 +00:00
Fam Zheng
f71eaa74c0 qmp: Add optional switch "query-nodes" in query-blockstats
This bool option will allow query all the node names. It iterates all
the BDSes that are assigned a name, also in this case don't query up the
backing chain.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10 10:25:29 +01:00
Amos Kong
b5369dd841 qmp: fix typo in input-send-event examples
Lack of two closed bracket in json commands.

Signed-off-by: Amos Kong <akong@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2014-12-10 11:14:44 +03:00
Gerd Hoffmann
df5b2adb73 input: move input-send-event into experimental namespace
Ongoing discussions on how we are going to specify the console,
so tag the command as experiental so we can refine things in
the 2.3 development cycle.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-id: 1416923657-10614-1-git-send-email-armbru@redhat.com
[Spell out "not a stable API", and x- the QAPI schema, too]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Amos Kong <akong@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-11-25 17:03:31 +00:00
Amos Kong
51fc44768a QMP/input-send-event: make console parameter optional
The 'QemuConsole' is the input source for handler, we share some
input handlers to process the input events from different QemuConsole.

Normally we only have one set of keyboard, mouse, usbtablet, etc.
The devices have different mask, it's fine to just checking mask to
insure that the handler has the ability to process the event.

I saw we try to bind console to handler in usb/dev-hid.c, but display
always isn't available at that time.

If we have multiseat setup (as Gerd said), we only have 'problem' in
this case. Actually event from different devices have the same effect
for system, it's fine to always use the first available handler
without caring about the console.

For send-key command, we just pass a NULL for console parameter in
calling qemu_input_event_send_key(NULL, ..), but 'input-send-event'
needs to care more devices.

Conclusion:
Generally assigning the special console is meanless, and we can't
directly remove the QMP parameter for compatibility.

So we can make the parameter optional. The parameter might be useful
for some special condition: we have multiple devices without binding
console and they all have the ability(mask) to process events, and
we don't want to use the first one.

Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Amos Kong <akong@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2014-11-13 11:06:40 +01:00
Marcelo Tosatti
50c6617fcb add input-send-event command
Which allows specification of absolute/relative,
up/down and console parameters.

Suggested by Gerd Hoffman.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2014-10-02 09:58:14 +02:00
Lluís Vilanova
1dde0f48d5 trace: [qmp] Add commands to query and control event tracing state
Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Message-id: 20140825111957.31112.31733.stgit@fimbulvetr.bsc.es
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-26 09:34:38 +01:00
Stefan Hajnoczi
550830f935 block: delete cow block driver
This patch removes support for the cow file format.

Normally we do not break backwards compatibility but in this case there
is no impact and it is the most logical option.  Extraordinary claims
require extraordinary evidence so I will show why removing the cow block
driver is the right thing to do.

The cow file format is the disk image format for Usermode Linux, a way
of running a Linux system in userspace.  The performance of UML was
never great and it was hacky, but it enjoyed some popularity before
hardware virtualization support became mainstream.

QEMU's block/cow.c is supposed to read this image file format.
Unfortunately the file format was underspecified:

1. Earlier Linux versions used the MAXPATHLEN constant for the backing
   filename field.  The value of MAXPATHLEN can change, so Linux
   switched to a 4096 literal but QEMU has a 1024 literal.

2. Padding was not used on the header struct (both in the Linux kernel
   and in QEMU) so the struct layout varied across architectures.  In
   particular, i386 and x86_64 were different due to int64_t alignment
   differences.  Linux now uses __attribute__((packed)), QEMU does not.

Therefore:

1. QEMU cow images do not conform to the Linux cow image file format.

2. cow images cannot be shared between different host architectures.

This means QEMU cow images are useless and QEMU has not had bug reports
from users actually hitting these issues.

Let's get rid of this thing, it serves no purpose and no one will be
affected.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-id: 1410877464-20481-1-git-send-email-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22 11:39:45 +01:00
Alexey Kardashevskiy
9cb805fd26 cpus: Define callback for QEMU "nmi" command
This introduces an NMI (Non Maskable Interrupt) interface with
a single nmi_monitor_handler() method. A machine or a device can
implement it. This searches for an QOM object with this interface
and if it is implemented, calls it. The callback implements an action
required to cause debug crash dump on in-kernel debugger invocation.
The callback returns Error**.

This adds a nmi_monitor_handle() helper which walks through
all objects to find the interface. The interface method is called
for all found instances.

This adds support for it in qmp_inject_nmi(). Since no architecture
supports it at the moment, there is no change in behaviour.

This changes inject-nmi command description for HMP and QMP.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-08-25 13:25:16 +02:00
Jeff Cody
13d8cc515d block: add backing-file option to block-stream
On some image chains, QEMU may not always be able to resolve the
filenames properly, when updating the backing file of an image
after a block job.

For instance, certain relative pathnames may fail, or drives may
have been specified originally by file descriptor (e.g. /dev/fd/???),
or a relative protocol pathname may have been used.

In these instances, QEMU may lack the information to be able to make
the correct choice, but the user or management layer most likely does
have that knowledge.

With this extension to the block-stream api, the user is able to change
the backing file of the active layer as part of the block-stream
operation.

This allows the change to be 'safe', in the sense that if the attempt
to write the active image metadata fails, then the block-stream
operation returns failure, without disrupting the guest.

If a backing file string is not specified in the command, the backing
file string to use is determined in the same manner as it was
previously.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-07-01 10:47:01 +02:00
Jeff Cody
54e2690090 block: extend block-commit to accept a string for the backing file
On some image chains, QEMU may not always be able to resolve the
filenames properly, when updating the backing file of an image
after a block commit.

For instance, certain relative pathnames may fail, or drives may
have been specified originally by file descriptor (e.g. /dev/fd/???),
or a relative protocol pathname may have been used.

In these instances, QEMU may lack the information to be able to make
the correct choice, but the user or management layer most likely does
have that knowledge.

With this extension to the block-commit api, the user is able to change
the backing file of the overlay image as part of the block-commit
operation.

This allows the change to be 'safe', in the sense that if the attempt
to write the overlay image metadata fails, then the block-commit
operation returns failure, without disrupting the guest.

If the commit top is the active layer, then specifying the backing
file string will be treated as an error (there is no overlay image
to modify in that case).

If a backing file string is not specified in the command, the backing
file string to use is determined in the same manner as it was
previously.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-07-01 10:47:01 +02:00
Jeff Cody
fa40e65622 block: add QAPI command to allow live backing file change
This allows a user to make a live change to the backing file recorded in
an open image.

The image file to modify can be specified 2 ways:

1) image filename
2) image node-name

Note: this does not cause the backing file itself to be reopened; it
merely changes the backing filename in the image file structure, and
in internal BDS structures.

It is the responsibility of the user to pass a filename string that
can be resolved when the image chain is reopened, and the filename
string is not validated.

A good analogy for this command is that it is a live version of
'qemu-img rebase -u', with respect to changing the backing file string.

[Jeff is offline so I respun this patch in his absence.  Dropped image
filename since using node-name is preferred and this is a new command.
No need to introduce the limitations of finding images by filename.
--Stefan]

Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-07-01 10:46:38 +02:00