In order to implement the new error handling and debugging
mechanism for command handlers, we need to change the cmd_new()
callback to return a value.

This commit introduces cmd_new_ret(), which returns a value and
will be used only temporarily to handle the transition from
cmd_new().

That is, as soon as all command handlers are ported to cmd_new_ret(),
it will be renamed back to cmd_new() and the new error handling
and debugging mechanism will be added on top of it.
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

QMP's chardev event callback doesn't call
json_message_parser_destroy() on CHR_EVENT_CLOSED. As the call
to json_message_parser_init() on CHR_EVENT_OPENED allocates memory,
we'are leaking on close.

Fix that by just calling json_message_parser_destroy() on
CHR_EVENT_CLOSED.
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Ideally, Monitor code should report an error only once and
return the error information up the call chain.

To assure that this happens as expected and that no error is
lost, we have an assert() in qemu_error_internal().

However, we still have not fully converted handlers using
monitor_printf() to report errors. As there can be multiple
monitor_printf() calls on an error, the assertion is easily
triggered when debugging is enabled; and we will get a memory
leak if it's not.

The solution to this problem is to allow multiple faults by only
reporting the first one, and to release the additional error objects.

A better mechanism to report multiple errors to programmers is
underway.
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

It's not needed to check the return of qobject_from_jsonf()
anymore, as an assert() has been added there.
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

With this commit QMP will be started in Capabilities Negotiation
mode, where the only command allowed to run is 'qmp_capabilities'.

All other commands will return CommandNotFound error. Asynchronous
messages are not delivered either.

When 'qmp_capabilities' is successfully executed QMP enters in
Command mode, where all commands (except 'qmp_capabilities') are
allowed to run and asynchronous messages are delivered.
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

This command will be used to enable QMP capabilities advertised
by the capabilities array.

Note that it will be mandatory to issue this command in order
to make QMP functional (although this behavior is not being
enforced by this commit).

Also, as we don't have any capabilities yet, the new command
doesn't accept any arguments. I will postpone the decision for
a format for this until we get our first capability.

Finally, this command is visible from the user Monitor too, in
the meaning that you can execute it but it won't do anything.
Making it only visible in QMP is beyond this series' goal, as
it requires changes in unrelated places.
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

With capability negotiation support clients will only have a chance
to check QEMU's version (ie. issue 'query-version') after the
negotiation procedure is done.

It might be useful to clients to check QEMU's version before
negotiating features, though.

To allow that, this commit adds the QEMU's version object to the
greeting message.

Not really sure this is needed, but doesn't hurt anyway.
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

This commit adds the basic definitions for the BLOCK_IO_ERROR
event, but actual event emission will be introduced by the
next commits.
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

This changes the error message from "Invalid CPU index" to "Invalid
parameter index" in the human monitor.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

This is a double value with optional suffixes ms, us, ns.  We'll need
this to get migrate_set_downtime() QMP-ready.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

This is a double value with optional suffixes G, g, M, m, K, k.  We'll
need this to get migrate_set_speed() QMP-ready.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Was forgotten in commit b6e098d7.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Function is_async_return() added by commit 940cc30d assumes
that 'data', which is returned by handlers, is always a QDict.

This is not true, as QLists can also be returned, in this case
we'll get a segfault.

Fix that by checking if 'data' is a QDict.
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

When using ballooning to manage overcommitted memory on a host, a system for
guests to communicate their memory usage to the host can provide information
that will minimize the impact of ballooning on the guests.  The current method
employs a daemon running in each guest that communicates memory statistics to a
host daemon at a specified time interval.  The host daemon aggregates this
information and inflates and/or deflates balloons according to the level of
host memory pressure.  This approach is effective but overly complex since a
daemon must be installed inside each guest and coordinated to communicate with
the host.  A simpler approach is to collect memory statistics in the virtio
balloon driver and communicate them directly to the hypervisor.
Signed-off-by: NAdam Litke <agl@us.ibm.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Qemu has a number of commands that can operate asynchronously (savevm, migrate,
etc) and it will be getting more.  For these commands, the user monitor needs
to be suspended, but QMP monitors could continue to to accept other commands.
This patch introduces a new command API that isolates the details of handling
different monitor types from the actual command execution.

A monitor command can use this API by implementing the mhandler.cmd_async
handler (or info_async if appropriate).  This function is responsible for
submitting the command and does not return any data although it may raise
errors.  When the command completes, the QMPCompletion callback should be
invoked with its opaque data and the command result.

The process for submitting and completing an asynchronous command is different
for QMP and user monitors.  A user monitor must be suspended at submit time and
resumed at completion time.  The user_print() function must be passed to the
QMPCompletion callback so the result can be displayed properly.  QMP monitors
are simpler.  No submit time setup is required.  When the command completes,
monitor_protocol_emitter() writes the result in JSON format.

This API can also be used to implement synchronous commands.  In this case, the
cmd_async handler should immediately call the QMPCompletion callback.  It is my
hope that this new interface will work for all commands, leading to a
drastically simplified monitor.c once all commands are ported.
Signed-off-by: NAdam Litke <agl@us.ibm.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

The returned QObject is a QList of all buses. Each bus is
represented by a QDict, which has a key with a QList of all
PCI devices attached to it. Each device is represented by
a QDict.

As has happended to other complex conversions, it's hard to
split this commit as part of it are new functions which are
called by each other.

IMPORTANT: support for printing PCI bridge attached devices
is NOT part of this commit, it's going to be added by the
next commit, as it's untested.
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

CC    i386-softmmu/monitor.o
cc1: warnings being treated as errors
/usr/src/RPM/BUILD/qemu-0.11.92/monitor.c: In function 'do_memory_save':
/usr/src/RPM/BUILD/qemu-0.11.92/monitor.c:1318: error: ignoring return value of 'fwrite', declared with attribute warn_unused_result
/usr/src/RPM/BUILD/qemu-0.11.92/monitor.c: In function 'do_physical_memory_save':
/usr/src/RPM/BUILD/qemu-0.11.92/monitor.c:1345: error: ignoring return value of 'fwrite', declared with attribute warn_unused_result
make[1]: *** [monitor.o] Error 1
Signed-off-by: NKirill A. Shutemov <kirill@shutemov.name>
Signed-off-by: NJuan Quintela <quintela@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

mon_get_cpu() can't return null pointer, because it passes its return
value to cpu_synchronize_state() first, which crashes if its argument
is null.

Remove the (pretty cheesy) handling of this non-existing error.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Commit f039a563 introduces
a regression as monitor_protocol_event() will return in
the first user Monitor it finds in the QLIST_FOREACH()
loop.

The right thing to do is to only delivery an asynchronous
event if the 'mon' is a QMP Monitor.

The aforementioned commit was an early version, if it was
applied to stable (it should) this one has to be applied
there too.
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Clean-up a little bit the RW related bits of BDRV_O_FLAGS. BDRV_O_RDONLY gone (and so is BDRV_O_ACCESS). Default value for bdrv_flags (0/zero) is READ-ONLY. Need to explicitly request READ-WRITE.

Instead of using the field 'readonly' of the BlockDriverState struct for passing the request,
pass the request in the flags parameter to the function.
Signed-off-by: NNaphtali Sprei <nsprei@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

When using a control/QMP monitor in tandem with a regular monitor, asynchronous
messages can get lost depending on the order of the QEMU program arguments.
QEMU events issued by monitor_protocol_event() always go to cur_mon.  If the
user monitor was specified on the command line first (or it has ,default), the
message will be directed to the user monitor (not the QMP monitor).
Additionally, only one QMP session is currently able to receive async messages.

To avoid this confusion, scan through the list of monitors and emit the message
on each QMP monitor.
Signed-off-by: NAdam Litke <agl@us.ibm.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

It's emitted when a VNC client session is activated by QEMU,
client's information such as port, IP and auth ID (if the
session is authenticated) are provided.

Event example:

{ "event": "VNC_INITIALIZED",
    "timestamp": {"seconds": 1263475302, "microseconds": 150772},
    "data": {
        "server": { "auth": "sasl", "family": "ipv4",
                    "service": "5901", "host": "0.0.0.0"},
        "client": { "family": "ipv4", "service": "46089",
                    "host": "127.0.0.1", "sasl_username": "lcapitulino" } } }
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

It's emitted when a VNC client disconnects from QEMU, client's
information such as port and IP address are provided.

Event example:

{ "event": "VNC_DISCONNECTED",
    "timestamp": { "seconds": 1262976601, "microseconds": 975795 },
    "data": {
        "server": { "auth": "sasl", "family": "ipv4",
                    "service": "5901", "host": "0.0.0.0" },
        "client": { "family": "ipv4", "service": "58425",
                    "host": "127.0.0.1", "sasl_username": "foo" } } }
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

It's emitted when a VNC client connects to QEMU, client's information
such as port and IP address are provided.

Note that this event is emitted right when the connection is
established. This means that it happens before authentication
procedure and session initialization.

Event example:

{ "event": "VNC_CONNECTED",
    "timestamp": { "seconds": 1262976601, "microseconds": 975795 },
    "data": {
        "server": { "auth": "sasl", "family": "ipv4",
                    "service": "5901", "host": "0.0.0.0" },
        "client": { "family": "ipv4", "service": "58425",
                    "host": "127.0.0.1" } } }
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Value stored to 'nb_per_line' is never read.
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

The monitor_protocol_event() function will free the
event's data, this is wrong as 'data' management is up
to the caller.
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Some commands return a QList of QDicts, which is valid,
but will trig the assert().

Just drop it.
Reported-by: NNathan Baum <nathan@parenthephobia.org.uk>
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

This makes do_balloon() accept megabyte values from the user
Monitor while accepting byte values for QMP.
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

This is a target long value in megabytes which should be
converted to bytes.

It will be used by handlers which accept a megabyte value
when in "user mode".
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

This is for debug purposes only.
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Currently, when a regular command doesn't have any data to output,
QMP will emit:

{ "return": "OK" }

Returning an empty dict is better though, because dicts can support
some protocol changes in a compatible way.

So, with this commit we will return:

{ "return": {} }
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Looks like I dropped this check when addressing the 'query-'
commands request.

QMP should only handle converted commands, obviously.
Reported-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

This allows to suspend command interpretation and execution
synchronously, e.g. during migration.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

The monitor_vprintf() function now touches the 'mon' pointer
before calling monitor_puts(), this causes block migration
to segfault as its functions call monitor_printf() with a
NULL 'mon'.

To fix the problem this commit moves the 'mon' NULL check
from monitor_puts() to monitor_vprintf().

This can potentially hide bugs, but for some reason this has
been the behavior for a long time.
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

The monitor_read_command() function is readline specific
and should only be used when readline is available.
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

do_balloon() should check for ballooning availability as
do_info_balloon() does.

Noted by Daniel P. Berrange <berrange@redhat.com>.
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Monitor's eject command uses 'filename' for the device name
argument, but 'device' is a better name.
Signed-off-by: NLuiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>