Sometimes, the behaviour of QEMU changes without a change in the QMP
syntax (usually by allowing values or operations that previously
resulted in an error). QMP clients may still need to know whether
they can rely on the changed behavior.
Let's add feature flags to the QAPI schema language, so that we can make
such changes visible with schema introspection.
An example for a schema definition using feature flags looks like this:
{ 'struct': 'TestType',
'data': { 'number': 'int' },
'features': [ 'allow-negative-numbers' ] }
Introspection information then looks like this:
{ "name": "TestType", "meta-type": "object",
"members": [
{ "name": "number", "type": "int" } ],
"features": [ "allow-negative-numbers" ] }
This patch implements feature flags only for struct types. We'll
implement them more widely as needed.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20190606153803.5278-2-armbru@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Wrap generated enum and struct members and their supporting code with
#if/#endif, using the .ifcond members added in the previous patches.
We do enum and struct in a single patch because union tag enum and the
associated variants tie them together, and dealing with that to split
the patch doesn't seem worthwhile.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20181213123724.4866-18-marcandre.lureau@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
This will allow to add and access more properties associated with enum
values/members, like the associated 'if' condition. We may want to
have a specialized type QAPISchemaEnumMember, for now this will do.
Modify gen_enum() and gen_enum_lookup() for the same reason.
Suggested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20181213123724.4866-3-marcandre.lureau@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
We consciously chose in commit 1a9a507b to hide QAPI type names
from the introspection output on the wire, but added a command
line option -u to unmask the type name when doing a debug build.
The unmask option still remains useful to some other forms of
automated analysis, so it will not be removed; however, when it
is not in use, the generated .c file can be hard to read. At
the time when we first introduced masking, the generated file
consisted only of a monolithic C string, so there was no clean
way to inject any comments.
Later, in commit 7d0f982b, we switched the generation to output
a QLit object, in part to make it easier for future addition of
conditional compilation. In fact, commit d626b6c1 took advantage
of this by passing a tuple instead of a bare object for encoding
the output of conditionals. By extending that tuple, we can now
interject strategic comments.
For now, type name debug aid comments are only output once per
meta-type, rather than at all uses of the number used to encode
the type within the introspection data. But this is still a lot
more convenient than having to regenerate the file with the
unmask operation temporarily turned on - merely search the
generated file for '"NNN" =' to learn the corresponding source
name and associated definition of type NNN.
The generated qapi-introspect.c changes only with the addition
of comments, such as:
| @@ -14755,6 +15240,7 @@
| { "name", QLIT_QSTR("[485]"), },
| {}
| })),
| + /* "485" = QCryptoBlockInfoLUKSSlot */
| QLIT_QDICT(((QLitDictEntry[]) {
| { "members", QLIT_QLIST(((QLitObject[]) {
| QLIT_QDICT(((QLitDictEntry[]) {
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180827213943.33524-3-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Rebased, update to qapi-code-gen.txt corrected]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Commit 7d0f982b changed generated introspection output to no longer
produce long lines in the generated .c file, but failed to adjust
comments to match. Add some clarity that the shorter length that
matters most is the overall QMP response on the wire.
Commit 25b1ef31 triggers a pep8 formatting nit.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180827213943.33524-2-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Making 'allow-oob' optional in SchemaInfoCommand permits omitting it
in the common case. Shrinks query-qmp-schema's output from 122.1KiB
to 118.6KiB for me.
Note that out-of-band execution is still experimental (you have to
configure the monitor with x-oob=on to use it).
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180718090557.17248-1-armbru@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
According to commit 047f7038f5, option --preconfig
[...] allows pausing QEMU in the new RUN_STATE_PRECONFIG state,
allowing the configuration of QEMU from QMP before the machine
jumps into board initialization code of machine_run_board_init()
The intent is to allow management to query machine state and
additionally configure it using previous query results within one
QEMU instance (i.e. eliminate the need to start QEMU twice, 1st to
query board specific parameters and 2nd for actual VM start using
query results for additional parameters).
The implementation is a bit of a hack: it splices in an additional
main loop before machine creation, in special runstate preconfig. New
command exit-preconfig exits that main loop. QEMU continues
initializing, creates the machine, and runs the good old main loop.
The replacement of the main loop is transparent to monitors.
Sadly, some commands expect initialization to be complete. Running
them in --preconfig's main loop violates their preconditions. Since
we don't really know which commands are safe, we use a whitelist.
This drags the concept of run state into the QMP core.
The whitelist is done as a command flag in the QAPI schema (commit
d6fe3d02e9). Drags the concept of run state further into the QAPI
language.
The command flag is exposed in query-qmp-schema (also commit
d6fe3d02e9). This makes it ABI.
I consider the whole thing an offensively ugly hack, but sometimes an
ugly hack is the best we can do to solve a problem people have.
The need described by the commit message quote above is genuine. The
proper solution would be a main loop that permits complete
configuration via QMP. This is out of reach, thus the hack.
However, even though the need is genuine, it isn't urgent: libvirt is
not going to use this anytime soon. Baking a hack into ABI before it
has any users is a bad idea.
This commit reverts the parts of commit d6fe3d02e9 that affect ABI
via query-qmp-schema. The commit did the following:
(1) Add command flag 'allow-preconfig' to the QAPI schema language
(2) Pass it to code generators
(3) Have the commands.py code generator pass it to the command
registry (so commit 047f7038f5 can use it as whitelist)
(4) Add 'allow-preconfig' to SchemaInfoCommand (neglecting to update
qapi-code-gen.txt section "Client JSON Protocol introspection")
(5) Set 'allow-preconfig': true for commands qmp_capabilities,
query-commands, query-command-line-options, query-status
Revert exactly (4), plus a bit of documentation added to
qemu-tech.info in commit 047f7038f5.
Shrinks query-qmp-schema's output from 126.5KiB to 121.8KiB for me.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180705091402.26244-2-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Acked-by: Eduardo Habkost <ehabkost@redhat.com>
Acked-by: Igor Mammedov <imammedo@redhat.com>
[Straightforward conflict with commit d626b6c1ae resolved]
This commit adds 'ifcond' conditions to top-level QLit objects.
Future work will add them to object and enum type members, i.e. within
QLit objects.
Extend the QLit generator to_qlit() to accept (@obj, @cond) tuples in
addition to just @obj. The tuple causes the QLit generated for
objects for @obj with #if/#endif conditions for @cond.
See generated tests/test-qmp-introspect.c. Example diff after this
patch:
--- before 2018-01-08 11:55:24.757083654 +0100
+++ tests/test-qmp-introspect.c 2018-01-08 13:08:44.477641629 +0100
@@ -51,6 +51,8 @@
{ "name", QLIT_QSTR("EVENT_F"), },
{}
})),
+#if defined(TEST_IF_CMD)
+#if defined(TEST_IF_STRUCT)
QLIT_QDICT(((QLitDictEntry[]) {
{ "arg-type", QLIT_QSTR("5"), },
{ "meta-type", QLIT_QSTR("command"), },
@@ -58,12 +60,16 @@
{ "ret-type", QLIT_QSTR("0"), },
{}
})),
+#endif /* defined(TEST_IF_STRUCT) */
+#endif /* defined(TEST_IF_CMD) */
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180703155648.11933-9-marcandre.lureau@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The following patch is going to break list entries with #if/#endif, so
they should have the trailing ',' as suffix.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180703155648.11933-8-marcandre.lureau@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Modify the test visitor to check correct passing of values.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180703155648.11933-5-marcandre.lureau@redhat.com>
[Accidental change to roms/seabios dropped]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Commit 1a9a507b2e "qapi-introspect: Hide type names" added local
variable @jsons to improve sorting, but also removed the sorting. It
was part of a big series that went to v8, and it made sense until v2
or so...
Commit 7d0f982bfb replaced @jsons by @qlits, preserving the
uselessness.
Get rid of it.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180620124742.16979-1-armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
New option will be used to allow commands, which are prepared/need
to run, during preconfig state. Other commands that should be able
to run in preconfig state, should be amended to not expect machine
in initialized state or deal with it.
For compatibility reasons, commands that don't use new flag
'allow-preconfig' explicitly are not permitted to run in
preconfig state but allowed in all other states like they used
to be.
Within this patch allow following commands in preconfig state:
qmp_capabilities
query-qmp-schema
query-commands
query-command-line-options
query-status
exit-preconfig
to allow qmp connection, basic introspection and moving to the next
state.
PS:
set-numa-node and query-hotpluggable-cpus will be enabled later in
a separate patches.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Message-Id: <1526057503-39287-1-git-send-email-imammedo@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[ehabkost: Changed "since 2.13" to "since 3.0"]
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Here "oob" stands for "Out-Of-Band". When "allow-oob" is set, it means
the command allows out-of-band execution.
The "oob" idea is proposed by Markus Armbruster in following thread:
https://lists.gnu.org/archive/html/qemu-devel/2017-09/msg02057.html
This new "allow-oob" boolean will be exposed by "query-qmp-schema" as
well for command entries, so that QMP clients can know which commands
can be used in out-of-band calls. For example the command "migrate"
originally looks like:
{"name": "migrate", "ret-type": "17", "meta-type": "command",
"arg-type": "86"}
And it'll be changed into:
{"name": "migrate", "ret-type": "17", "allow-oob": false,
"meta-type": "command", "arg-type": "86"}
This patch only provides the QMP interface level changes. It does not
contain the real out-of-band execution implementation yet.
Suggested-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180309090006.10018-18-peterx@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[eblake: rebase on introspection done by qlit]
Signed-off-by: Eric Blake <eblake@redhat.com>
Replace the generated json string with a literal qobject. The later is
easier to deal with, at run time as well as compile time: adding #if
conditionals will be easier than in a json string.
The output of query-qmp-schema is not changed.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180305172951.2150-5-marcandre.lureau@redhat.com>
[eblake: fix python 3 failure]
Signed-off-by: Eric Blake <eblake@redhat.com>
Move qapi-schema.json to qapi/, so it's next to its modules, and all
files get generated to qapi/, not just the ones generated for modules.
Consistently name the generated files qapi-MODULE.EXT:
qmp-commands.[ch] become qapi-commands.[ch], qapi-event.[ch] become
qapi-events.[ch], and qmp-introspect.[ch] become qapi-introspect.[ch].
This gets rid of the temporary hacks in scripts/qapi/commands.py,
scripts/qapi/events.py, and scripts/qapi/common.py.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180211093607.27351-28-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
[eblake: Fix trailing dot in tpm.c, undo temporary hack for OSX toolchain]
Signed-off-by: Eric Blake <eblake@redhat.com>
The use of QAPIGen is rather shallow so far: most of the output
accumulation is not converted. Take the next step: convert output
accumulation in the code-generating visitor classes. Helper functions
outside these classes are not converted.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180211093607.27351-20-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
[eblake: rebase to earlier guardstart cleanup]
Signed-off-by: Eric Blake <eblake@redhat.com>
Whenever qapi-schema.json changes, we run six programs eleven times to
update eleven files. Similar for qga/qapi-schema.json. This is
silly. Replace the six programs by a single program that spits out
all eleven files.
The programs become modules in new Python package qapi, along with the
helper library. This requires moving them to scripts/qapi/. While
moving them, consistently drop executable mode bits.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20180211093607.27351-9-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
[eblake: move change to one-line 'blurb' earlier in series, mention mode
bit change as intentional, update qapi-code-gen.txt to match actual
generated events.c file]
Signed-off-by: Eric Blake <eblake@redhat.com>
