Commit Graph

1111 Commits

Author SHA1 Message Date
Markus Armbruster 30cc98315f monitor: Clean up how monitor_disas() funnels output to monitor
INIT_DISASSEMBLE_INFO() takes an fprintf()-like callback and a FILE *
to pass to it.  monitor_disas() passes monitor_fprintf() and the
current monitor cast to FILE *.  monitor_fprintf() casts it right
back, and is otherwise identical to monitor_printf().  The
type-punning is ugly.

Pass qemu_fprintf() and NULL instead.

monitor_fprintf() is now unused; delete it.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20190417191805.28198-16-armbru@redhat.com>
[Commit message typo corrected]
2019-04-18 22:18:59 +02:00
Markus Armbruster 90c84c5600 qom/cpu: Simplify how CPUClass:cpu_dump_state() prints
CPUClass method dump_statistics() takes an fprintf()-like callback and
a FILE * to pass to it.  Most callers pass fprintf() and stderr.
log_cpu_state() passes fprintf() and qemu_log_file.
hmp_info_registers() passes monitor_fprintf() and the current monitor
cast to FILE *.  monitor_fprintf() casts it right back, and is
otherwise identical to monitor_printf().

The callback gets passed around a lot, which is tiresome.  The
type-punning around monitor_fprintf() is ugly.

Drop the callback, and call qemu_fprintf() instead.  Also gets rid of
the type-punning, since qemu_fprintf() takes NULL instead of the
current monitor cast to FILE *.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20190417191805.28198-15-armbru@redhat.com>
2019-04-18 22:18:59 +02:00
Markus Armbruster 11cb6c152a qom/cpu: Simplify how CPUClass::dump_statistics() prints
CPUClass method dump_statistics() takes an fprintf()-like callback and
a FILE * to pass to it.

Its only caller hmp_info_cpustats() (via cpu_dump_statistics()) passes
monitor_fprintf() and the current monitor cast to FILE *.
monitor_fprintf() casts it right back, and is otherwise identical to
monitor_printf().  The type-punning is ugly.

Drop the callback, and call qemu_printf() instead.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20190417191805.28198-13-armbru@redhat.com>
2019-04-18 22:18:59 +02:00
Markus Armbruster b6b71cb5c6 memory: Clean up how mtree_info() prints
mtree_info() takes an fprintf()-like callback and a FILE * to pass to
it, and so do its helper functions.  Passing around callback and
argument is rather tiresome.

Its only caller hmp_info_mtree() passes monitor_printf() cast to
fprintf_function and the current monitor cast to FILE *.

The type-punning is technically undefined behaviour, but works in
practice.  Clean up: drop the callback, and call qemu_printf()
instead.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20190417191805.28198-9-armbru@redhat.com>
2019-04-18 22:18:59 +02:00
Markus Armbruster ac7ff4cf5f qsp: Simplify how qsp_report() prints
qsp_report() takes an fprintf()-like callback and a FILE * to pass to
it.

Its only caller hmp_sync_profile() passes monitor_fprintf() and the
current monitor cast to FILE *.  monitor_fprintf() casts it right
back, and is otherwise identical to monitor_printf().  The
type-punning is ugly.

Drop the callback, and call qemu_printf() instead.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20190417191805.28198-7-armbru@redhat.com>
2019-04-18 22:18:59 +02:00
Markus Armbruster 76c8661595 tcg: Simplify how dump_drift_info() prints
dump_drift_info() takes an fprintf()-like callback and a FILE * to pass
to it.

Its only caller hmp_info_jit() passes monitor_fprintf() and a Monitor
* cast to FILE *.  monitor_fprintf() casts it right back, and is
otherwise identical to monitor_printf().  The type-punning is ugly.

Drop the callback, and call qemu_printf() instead.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20190417191805.28198-6-armbru@redhat.com>
2019-04-18 22:18:59 +02:00
Markus Armbruster 3de2faa9a8 tcg: Simplify how dump_exec_info() prints
dump_exec_info() takes an fprintf()-like callback and a FILE * to pass
to it.

Its only caller hmp_info_jit() passes monitor_fprintf() and the
current monitor cast to FILE *.  monitor_fprintf() casts it right
back, and is otherwise identical to monitor_printf().  The
type-punning is ugly.

Drop the callback, and call qemu_printf() instead.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20190417191805.28198-5-armbru@redhat.com>
2019-04-18 22:18:59 +02:00
Markus Armbruster d4c51a0af3 tcg: Simplify how dump_opcount_info() prints
dump_opcount_info() takes an fprintf()-like callback and a FILE * to
pass to it.

Its only caller hmp_info_opcount() passes monitor_fprintf() and the
current monitor cast to FILE *.  monitor_fprintf() casts it right
back, and is otherwise identical to monitor_printf().  The
type-punning is ugly.

Drop the callback, and call qemu_printf() instead.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20190417191805.28198-4-armbru@redhat.com>
2019-04-18 22:18:59 +02:00
Markus Armbruster ba4912cb0d trace: Simplify how st_print_trace_file_status() prints
st_print_trace_file_status() takes an fprintf()-like callback and a
FILE * to pass to it.

Its only caller hmp_trace_file() passes monitor_fprintf() and the
current monitor cast to FILE *.  monitor_fprintf() casts it right
back, and is otherwise identical to monitor_printf().  The
type-punning is ugly.

Drop the callback, and call qemu_printf() instead.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20190417191805.28198-3-armbru@redhat.com>
2019-04-18 22:18:59 +02:00
Markus Armbruster 8acb2a758b monitor: Simplify how -device/device_add print help
Commit a95db58f21 added monitor_vfprintf() as an error_printf()
generalized from stderr to arbitrary streams, then used it wrapped in
helper out_printf() to print -device/device_add help to stdout.  Use
qemu_printf() instead, and delete monitor_vfprintf() and out_printf().

Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20190417190641.26814-16-armbru@redhat.com>
2019-04-18 22:18:59 +02:00
Markus Armbruster 679cb8e1a1 monitor error: Make printf()-like functions return a value
printf() & friends return the number of characters written on success,
negative value on error.

monitor_printf(), monitor_vfprintf(), monitor_vprintf(),
error_printf(), error_printf_unless_qmp(), error_vprintf(), and
error_vprintf_unless_qmp() return void.  Some of them carry a TODO
comment asking for int instead.

Improve them to return int like printf() does.

This makes our use of monitor_printf() as fprintf_function slightly
less dirty: the function cast no longer adds a return value that isn't
there.  It still changes a parameter's pointer type.  That will be
addressed in a future commit.

monitor_vfprintf() always returns zero.  Improve it to return the
proper value.

Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20190417190641.26814-11-armbru@redhat.com>
2019-04-18 22:18:59 +02:00
Marc-André Lureau 4eaca8de26 qmp: common 'id' handling & make QGA conform to QMP spec
Let qmp_dispatch() copy the 'id' field. That way any qmp client will
conform to the specification, including QGA. Furthermore, it
simplifies the work for qemu monitor.

CC: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
2019-03-18 10:48:06 -05:00
Daniel P. Berrangé 0143840771 monitor: deprecate acl_show, acl_reset, acl_policy, acl_add, acl_remove
The various ACL related commands are obsolete now that the QAuthZ
framework for authorization is fully integrated throughout QEMU network
services. These only ever worked with VNC and were never used by libvirt.
Mark it as deprecated with no direct replacement to be provided.

Authorization is now provided by using 'object_add' together with
the 'tls-authz' or 'sasl-authz' parameters to the VNC server, and
equivalent for other network services.

Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20190227145755.26556-3-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2019-03-11 08:39:02 +01:00
Daniel P. Berrange b76806d4ec authz: delete existing ACL implementation
The 'qemu_acl' type was a previous non-QOM based attempt to provide an
authorization facility in QEMU. Because it is non-QOM based it cannot be
created via the command line and requires special monitor commands to
manipulate it.

The new QAuthZ subclasses provide a superset of the functionality in
qemu_acl, so the latter can now be deleted. The HMP 'acl_*' monitor
commands are converted to use the new QAuthZSimple data type instead
in order to provide temporary backwards compatibility.

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2019-02-26 15:32:19 +00:00
Markus Armbruster 9d7b70864a qmp: Deprecate query-events in favor of query-qmp-schema
query-events doesn't reflect compile-time configuration.  Instead of
fixing that, deprecate the command in favor of query-qmp-schema.

Libvirt prefers query-qmp-schema as of commit 22d7222ec0 "qemu: caps:
Don't call 'query-events' when we probe events from QMP schema".
It'll be in the next release.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20190214152251.2073-18-armbru@redhat.com>
2019-02-18 14:44:05 +01:00
Marc-André Lureau 25a9d6ca63 qapi: make query-cpu-definitions depend on specific targets
It depends on TARGET_PPC || TARGET_ARM || TARGET_I386 || TARGET_S390X.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190214152251.2073-15-armbru@redhat.com>
2019-02-18 14:44:05 +01:00
Marc-André Lureau 96f75b59b6 qapi: make query-cpu-model-expansion depend on s390 or x86
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190214152251.2073-14-armbru@redhat.com>
2019-02-18 14:44:05 +01:00
Marc-André Lureau 84c6499eb1 qapi: make query-gic-capabilities depend on TARGET_ARM
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190214152251.2073-13-armbru@redhat.com>
2019-02-18 14:44:05 +01:00
Marc-André Lureau 0e2f4530c1 qapi: make s390 commands depend on TARGET_S390X
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190214152251.2073-11-armbru@redhat.com>
2019-02-18 14:44:05 +01:00
Marc-André Lureau a6c7040fb0 qapi: make rtc-reset-reinjection and SEV depend on TARGET_I386
Move rtc-reset-reinjection and SEV in target.json and make them
conditional on TARGET_I386.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190214152251.2073-10-armbru@redhat.com>
2019-02-18 14:44:04 +01:00
Markus Armbruster 5d75648b56 qapi: Generate QAPIEvent stuff into separate files
Having to include qapi-events.h just for QAPIEvent is suboptimal, but
quite tolerable now.  It'll become problematic when we have events
conditional on the target, because then qapi-events.h won't be usable
from target-independent code anymore.  Avoid that by generating it
into separate files.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20190214152251.2073-6-armbru@redhat.com>
2019-02-18 14:44:04 +01:00
Paolo Bonzini 82e870bac4 monitor: do not use QTAILQ_FOREACH_SAFE across critical sections
monitor_qmp_requests_pop_any_with_lock cannot modify the monitor list
concurrently with monitor_cleanup, since the dispatch bottom half
runs in the main thread, but anyway it is a bit ugly to keep
"next" live across critical sections of monitor_lock and Coverity
complains (CID 1397072).

Replace QTAILQ_FOREACH_SAFE with a while loop and QTAILQ_FIRST,
it is cleaner and more future-proof.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-02-05 16:50:18 +01:00
Markus Armbruster a95291007b qapi: Eliminate indirection through qmp_event_get_func_emit()
The qapi_event_send_FOO() functions emit events like this:

    QMPEventFuncEmit emit;

    emit = qmp_event_get_func_emit();
    if (!emit) {
        return;
    }

    qmp = qmp_event_build_dict("FOO");
    [put event arguments into @qmp...]

    emit(QAPI_EVENT_FOO, qmp);

The value of qmp_event_get_func_emit() depends only on the program:

* In qemu-system-FOO, it's always monitor_qapi_event_queue.

* In tests/test-qmp-event, it's always event_test_emit.

* In all other programs, it's always null.

This is exactly the kind of dependence the linker is supposed to
resolve; we don't actually need an indirection.

Note that things would fall apart if we linked more than one QAPI
schema into a single program: each set of qapi_event_send_FOO() uses
its own event enumeration, yet they share a single emit function.
Which takes the event enumeration as an argument.  Which one if
there's more than one?

More seriously: how does this work even now?  qemu-system-FOO wants
QAPIEvent, and passes a function taking that to
qmp_event_set_func_emit().  test-qmp-event wants test_QAPIEvent, and
passes a function taking that to qmp_event_set_func_emit().

It works by type trickery, of course:

    typedef void (*QMPEventFuncEmit)(unsigned event, QDict *dict);

    void qmp_event_set_func_emit(QMPEventFuncEmit emit);

    QMPEventFuncEmit qmp_event_get_func_emit(void);

We use unsigned instead of the enumeration type.  Relies on both
enumerations boiling down to unsigned, which happens to be true for
the compilers we use.

Clean this up as follows:

* Generate qapi_event_send_FOO() that call PREFIX_qapi_event_emit()
  instead of the value of qmp_event_set_func_emit().

* Generate a prototype for PREFIX_qapi_event_emit() into
  qapi-events.h.

* PREFIX_ is empty for qapi/qapi-schema.json, and test_ for
  tests/qapi-schema/qapi-schema-test.json.  It's qga_ for
  qga/qapi-schema.json, and doc-good- for
  tests/qapi-schema/doc-good.json, but those don't define any events.

* Rename monitor_qapi_event_queue() to qapi_event_emit() instead of
  passing it to qmp_event_set_func_emit().  This takes care of
  qemu-system-FOO.

* Rename event_test_emit() to test_qapi_event_emit() instead of
  passing it to qmp_event_set_func_emit().  This takes care of
  tests/test-qmp-event.

* Add a qapi_event_emit() that does nothing to stubs/monitor.c.  This
  takes care of all other programs that link code emitting QMP events.

* Drop qmp_event_set_func_emit(), qmp_event_get_func_emit().

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20181218182234.28876-3-armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
[Commit message typos fixed]
2019-01-24 10:01:05 +01:00
Paolo Bonzini b58deb344d qemu/queue.h: leave head structs anonymous unless necessary
Most list head structs need not be given a name.  In most cases the
name is given just in case one is going to use QTAILQ_LAST, QTAILQ_PREV
or reverse iteration, but this does not apply to lists of other kinds,
and even for QTAILQ in practice this is only rarely needed.  In addition,
we will soon reimplement those macros completely so that they do not
need a name for the head struct.  So clean up everything, not giving a
name except in the rare case where it is necessary.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-01-11 15:46:55 +01:00
Peter Maydell b019f5e537 miscellaneous patches:
* checkpatch.pl: Enforce multiline comment syntax
  * Rename cpu_physical_memory_write_rom() to address_space_write_rom()
  * disas, monitor, elf_ops: Use address_space_read() to read memory
  * Remove load_image() in favour of load_image_size()
  * Fix some minor memory leaks in arm boards/devices
  * virt: fix broken indentation
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Merge remote-tracking branch 'remotes/pmaydell/tags/pull-misc-20181214' into staging

miscellaneous patches:
 * checkpatch.pl: Enforce multiline comment syntax
 * Rename cpu_physical_memory_write_rom() to address_space_write_rom()
 * disas, monitor, elf_ops: Use address_space_read() to read memory
 * Remove load_image() in favour of load_image_size()
 * Fix some minor memory leaks in arm boards/devices
 * virt: fix broken indentation

# gpg: Signature made Fri 14 Dec 2018 14:41:20 GMT
# gpg:                using RSA key 3C2525ED14360CDE
# gpg: Good signature from "Peter Maydell <peter.maydell@linaro.org>"
# gpg:                 aka "Peter Maydell <pmaydell@gmail.com>"
# gpg:                 aka "Peter Maydell <pmaydell@chiark.greenend.org.uk>"
# Primary key fingerprint: E1A5 C593 CD41 9DE2 8E83  15CF 3C25 25ED 1436 0CDE

* remotes/pmaydell/tags/pull-misc-20181214: (22 commits)
  virt: Fix broken indentation
  target/arm: Create timers in realize, not init
  tests/test-arm-mptimer: Don't leak string memory
  hw/sd/sdhci: Don't leak memory region in sdhci_sysbus_realize()
  hw/arm/mps2-tz.c: Free mscname string in make_dma()
  target/arm: Free name string in ARMCPRegInfo hashtable entries
  include/hw/loader.h: Document load_image_size()
  hw/core/loader.c: Remove load_image()
  device_tree.c: Don't use load_image()
  hw/block/tc58128.c: Don't use load_image()
  hw/i386/multiboot.c: Don't use load_image()
  hw/i386/pc.c: Don't use load_image()
  hw/pci/pci.c: Don't use load_image()
  hw/smbios/smbios.c: Don't use load_image()
  hw/ppc/ppc405_boards: Don't use load_image()
  hw/ppc/mac_newworld, mac_oldworld: Don't use load_image()
  elf_ops.h: Use address_space_write() to write memory
  monitor: Use address_space_read() to read memory
  disas.c: Use address_space_read() to read memory
  Rename cpu_physical_memory_write_rom() to address_space_write_rom()
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-12-16 16:32:43 +00:00
Peter Maydell 6f89ae5816 monitor: Use address_space_read() to read memory
Currently monitor.c reads physical memory using
cpu_physical_memory_read(). This effectively hard-codes
assuming that all CPUs have the same view of physical
memory. Switch to address_space_read() instead, which
lets us use the AddressSpace for the CPU we're
reading memory for (falling back to address_space_memory
if there is no CPU, as happens with the "none" board).
As a bonus, this allows us to detect failures to read memory.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20181122172653.3413-3-peter.maydell@linaro.org
2018-12-14 13:30:49 +00:00
Marc-André Lureau 335d10cd8e qapi: add conditions to REPLICATION type/commands on the schema
Add #if defined(CONFIG_REPLICATION) in generated code, and adjust the
code accordingly.

Made conditional:

* xen-set-replication, query-xen-replication-status,
  xen-colo-do-checkpoint

  Before the patch, we first register the commands unconditionally in
  generated code (requires a stub), then conditionally unregister in
  qmp_unregister_commands_hack().

  Afterwards, we register only when CONFIG_REPLICATION.  The command
  fails exactly the same, with CommandNotFound.

  Improvement, because now query-qmp-schema is accurate, and we're one
  step closer to killing qmp_unregister_commands_hack().

* enum BlockdevDriver value "replication" in command blockdev-add

* BlockdevOptions variant @replication

and related structures.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20181213123724.4866-23-marcandre.lureau@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-12-14 06:52:48 +01:00
David Hildenbrand af02f4c517 cutils: Fix qemu_strtosz() & friends to reject non-finite sizes
qemu_strtosz() & friends reject NaNs, but happily accept infinities.
They shouldn't. Fix that.

The fix makes use of qemu_strtod_finite(). To avoid ugly casts,
change the @end parameter of qemu_strtosz() & friends from char **
to const char **.

Also, add two test cases, testing that "inf" and "NaN" are properly
rejected. While at it, also fixup the function documentation.

Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20181121164421.20780-3-david@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-12-13 19:10:06 +01:00
Peter Xu 8258292e18 monitor: Remove "x-oob", offer capability "oob" unconditionally
Out-of-band command execution was introduced in commit cf869d5317.
Unfortunately, we ran into a regression, and had to turn it into an
experimental option for 2.12 (commit be933ffc23).

  http://lists.gnu.org/archive/html/qemu-devel/2018-03/msg06231.html

The regression has since been fixed (commit 951702f39c "monitor: bind
dispatch bh to iohandler context").  A thorough re-review of OOB
commands led to a few more issues, which have also been addressed.

This patch partly reverts be933ffc23 (monitor: new parameter "x-oob"),
and makes QMP monitors again offer capability "oob" whenever they can
provide it, i.e. when the monitor's character device is capable of
running in an I/O thread.

Some trivial touch-up in the test code is required to make sure qmp-test
won't break.

Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20181009062718.1914-4-peterx@redhat.com>
[Conflict with "monitor: check if chardev can switch gcontext for OOB"
resolved, commit message updated]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-12-12 10:28:27 +01:00
Peter Xu 9ab84470ff monitor: Suspend monitor instead dropping commands
When a QMP client sends in-band commands more quickly that we can
process them, we can either queue them without limit (QUEUE), drop
commands when the queue is full (DROP), or suspend receiving commands
when the queue is full (SUSPEND).  None of them is ideal:

* QUEUE lets a misbehaving client make QEMU eat memory without bounds.
Not such a hot idea.

* With DROP, the client has to cope with dropped in-band commands.  To
inform the client, we send a COMMAND_DROPPED event then.  The event is
flawed by design in two ways: it's ambiguous (see commit d621cfe0a1),
and it brings back the "eat memory without bounds" problem.

* With SUSPEND, the client has to manage the flow of in-band commands to
keep the monitor available for out-of-band commands.

We currently DROP.  Switch to SUSPEND.

Managing the flow of in-band commands to keep the monitor available for
out-of-band commands isn't really hard: just count the number of
"outstanding" in-band commands (commands sent minus replies received),
and if it exceeds the limit, hold back additional ones until it drops
below the limit again.

Note that we need to be careful pairing the suspend with a resume, or
else the monitor will hang, possibly forever.  And here since we need to
make sure both:

     (1) popping request from the req queue, and
     (2) reading length of the req queue

will be in the same critical section, we let the pop function take the
corresponding queue lock when there is a request, then we release the
lock from the caller.

Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20181009062718.1914-2-peterx@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-12-12 09:55:57 +01:00
Marc-André Lureau 34f1f3e06d monitor: avoid potential dead-lock when cleaning up
When a monitor is connected to a Spice chardev, the monitor cleanup
can dead-lock:

 #0  0x00007f43446637fd in __lll_lock_wait () at /lib64/libpthread.so.0
 #1  0x00007f434465ccf4 in pthread_mutex_lock () at /lib64/libpthread.so.0
 #2  0x0000556dd79f22ba in qemu_mutex_lock_impl (mutex=0x556dd81c9220 <monitor_lock>, file=0x556dd7ae3648 "/home/elmarco/src/qq/monitor.c", line=645) at /home/elmarco/src/qq/util/qemu-thread-posix.c:66
 #3  0x0000556dd7431bd5 in monitor_qapi_event_queue (event=QAPI_EVENT_SPICE_DISCONNECTED, qdict=0x556dd9abc850, errp=0x7fffb7bbddd8) at /home/elmarco/src/qq/monitor.c:645
 #4  0x0000556dd79d476b in qapi_event_send_spice_disconnected (server=0x556dd98ee760, client=0x556ddaaa8560, errp=0x556dd82180d0 <error_abort>) at qapi/qapi-events-ui.c:149
 #5  0x0000556dd7870fc1 in channel_event (event=3, info=0x556ddad1b590) at /home/elmarco/src/qq/ui/spice-core.c:235
 #6  0x00007f434560a6bb in reds_handle_channel_event (reds=<optimized out>, event=3, info=0x556ddad1b590) at reds.c:316
 #7  0x00007f43455f393b in main_dispatcher_self_handle_channel_event (info=0x556ddad1b590, event=3, self=0x556dd9a7d8c0) at main-dispatcher.c:197
 #8  0x00007f43455f393b in main_dispatcher_channel_event (self=0x556dd9a7d8c0, event=event@entry=3, info=0x556ddad1b590) at main-dispatcher.c:197
 #9  0x00007f4345612833 in red_stream_push_channel_event (s=s@entry=0x556ddae2ef40, event=event@entry=3) at red-stream.c:414
 #10 0x00007f434561286b in red_stream_free (s=0x556ddae2ef40) at red-stream.c:388
 #11 0x00007f43455f9ddc in red_channel_client_finalize (object=0x556dd9bb21a0) at red-channel-client.c:347
 #12 0x00007f434b5f9fb9 in g_object_unref () at /lib64/libgobject-2.0.so.0
 #13 0x00007f43455fc212 in red_channel_client_push (rcc=0x556dd9bb21a0) at red-channel-client.c:1341
 #14 0x0000556dd76081ba in spice_port_set_fe_open (chr=0x556dd9925e20, fe_open=0) at /home/elmarco/src/qq/chardev/spice.c:241
 #15 0x0000556dd796d74a in qemu_chr_fe_set_open (be=0x556dd9a37c00, fe_open=0) at /home/elmarco/src/qq/chardev/char-fe.c:340
 #16 0x0000556dd796d4d9 in qemu_chr_fe_set_handlers (b=0x556dd9a37c00, fd_can_read=0x0, fd_read=0x0, fd_event=0x0, be_change=0x0, opaque=0x0, context=0x0, set_open=true) at /home/elmarco/src/qq/chardev/char-fe.c:280
 #17 0x0000556dd796d359 in qemu_chr_fe_deinit (b=0x556dd9a37c00, del=false) at /home/elmarco/src/qq/chardev/char-fe.c:233
 #18 0x0000556dd7432240 in monitor_data_destroy (mon=0x556dd9a37c00) at /home/elmarco/src/qq/monitor.c:786
 #19 0x0000556dd743b968 in monitor_cleanup () at /home/elmarco/src/qq/monitor.c:4683
 #20 0x0000556dd75ce776 in main (argc=3, argv=0x7fffb7bbe458, envp=0x7fffb7bbe478) at /home/elmarco/src/qq/vl.c:4660

Because spice code tries to emit a "disconnected" signal on the
monitors. Fix this dead-lock by releasing the monitor lock for
flush/destroy.

monitor_lock protects mon_list, monitor_qapi_event_state and
monitor_destroyed. monitor_flush() and monitor_data_destroy() don't
access any of those variables.

monitor_cleanup()'s loop is safe because it uses
QTAILQ_FOREACH_SAFE(), and no further monitor can be added after
calling monitor_cleanup() thanks to monitor_destroyed check in
monitor_list_append().

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20181205203737.9011-8-marcandre.lureau@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-12-12 09:55:57 +01:00
Marc-André Lureau 8dac00bbfb monitor: prevent inserting new monitors after cleanup
monitor_cleanup() is one of the last things main() calls before it
returns.  In the following patch, monitor_cleanup() will release the
monitor_lock during flushing. There may be pending commands to insert
new monitors, which would modify the mon_list during iteration, and
the clean-up could thus miss those new insertions.

Add a monitor_destroyed global to check if monitor_cleanup() has been
already called. In this case, don't insert the new monitor in the
list, but free it instead. A cleaner solution would involve the main
thread telling other threads to terminate, waiting for their
termination.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20181205203737.9011-7-marcandre.lureau@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-12-12 09:55:57 +01:00
Marc-André Lureau a9a0d9b99a monitor: check if chardev can switch gcontext for OOB
Not all backends are able to switch gcontext. Those backends cannot
drive a OOB monitor (the monitor would then be blocking on main
thread).

For example, ringbuf, spice, or more esoteric input chardevs like
braille or MUX.

We already forbid MUX because not all frontends are ready to run outside
main loop.  Replace that by a context-switching feature check.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20181205203737.9011-5-marcandre.lureau@redhat.com>
[Error condition simplified, commit message adjusted accordingly]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-12-12 09:55:57 +01:00
Marc-André Lureau ef12a703b7 monitor: accept chardev input from iothread
Chardev backends may not handle safely IO events from concurrent
threads (may not handle I/O events from concurrent threads safely,
only the write path is since commit >
9005b2a758). Better to wake up the
chardev from the monitor IO thread if it's being used as the chardev
context.

Unify code paths by using a BH in all cases.

Drop the now redundant aio_notify() call.

Clean up control flow not to rely on mon->use_io_thread implying
monitor_is_qmp(mon).

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20181205203737.9011-3-marcandre.lureau@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-12-12 09:55:57 +01:00
Marc-André Lureau 88e40e4347 monitor: inline ambiguous helper functions
The function were not named with "mon_iothread", or following the AIO
vs GMainContext distinction. Inline them instead.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20181205203737.9011-2-marcandre.lureau@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-12-12 09:55:57 +01:00
Wolfgang Bumiller 8511770185 monitor: delay monitor iothread creation
Commit d32749deb6 moved the call to monitor_init_globals()
to before os_daemonize(), making it an unsuitable place to
spawn the monitor iothread as it won't be inherited over the
fork() in os_daemonize().

We now spawn the thread the first time we instantiate a
monitor which actually has use_io_thread == true.
Instantiation of monitors happens only after os_daemonize().
We still need to create the qmp_dispatcher_bh when not using
iothreads, so this now still happens in
monitor_init_globals().

Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>
Fixes: d32749deb6 ("monitor: move init global earlier")
Message-Id: <20180925081507.11873-3-w.bumiller@proxmox.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Tested-by: Peter Xu <peterx@redhat.com>
[This fixes a crash on shutdown with --daemonize]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-11-06 17:02:49 +01:00
Wolfgang Bumiller 9a3e52e346 monitor: guard iothread access by mon->use_io_thread
monitor_resume() and monitor_suspend() both want to
"kick" the I/O thread if it is there, but in
monitor_suspend() lacked the use_io_thread flag condition.
This is required when we later only spawn the thread on
first use.

Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180925081507.11873-2-w.bumiller@proxmox.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-11-06 17:02:49 +01:00
Emilio G. Cota 72fd2efbbd tcg: distribute tcg_time into TCG contexts
When we implemented per-vCPU TCG contexts, we forgot to also
distribute the tcg_time counter, which has remained as a global
accessed without any serialization, leading to potentially missed
counts.

Fix it by distributing the field over the TCG contexts, embedding
it into TCGProfile with a field called "cpu_exec_time", which is more
descriptive than "tcg_time". Add a function to query this value
directly, and for completeness, fill in the field in
tcg_profile_snapshot, even though its callers do not use it.

Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <20181010144853.13005-5-cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2018-10-18 18:58:10 -07:00
Marc-André Lureau a95db58f21 qdev-monitor: print help to stdout
qdev_device_help() is used from command line "-device help", or from
HMP "device_add". If used from command line, print help to stdout
(it is only printed on explicit demand).

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2018-10-05 16:14:22 +04:00
Collin Walling 43e87b3eaf monitor: print message when using 'help' with an unknown command
When typing 'help' followed by an unknown command, QEMU will
not print anything to the command line to let the user know
they typed a bad command. Let's fix this by printing a message
to the monitor when this happens. For example:

    (qemu) help xyz
    unknown command: 'xyz'

Reported-by: Stefan Zimmermann <stzi@linux.ibm.com>
Signed-off-by: Collin Walling <walling@linux.ibm.com>
Message-Id: <1532115624-27568-1-git-send-email-walling@linux.ibm.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-09-25 14:48:44 +01:00
Peter Maydell efd1d5229f Monitor patches for 2018-09-01
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Merge remote-tracking branch 'remotes/armbru/tags/pull-monitor-2018-09-01' into staging

Monitor patches for 2018-09-01

# gpg: Signature made Sat 01 Sep 2018 12:06:52 BST
# gpg:                using RSA key 3870B400EB918653
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>"
# gpg:                 aka "Markus Armbruster <armbru@pond.sub.org>"
# Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867  4E5F 3870 B400 EB91 8653

* remotes/armbru/tags/pull-monitor-2018-09-01:
  monitor: no need to save need_resume
  Revert "qmp: isolate responses into io thread"
  qmp: constify qmp_is_oob()
  monitor: consitify qmp_send_response() QDict argument
  monitor: accept input on resume
  monitor: simplify monitor_qmp_setup_handlers_bh

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-09-24 15:43:33 +01:00
Marc-André Lureau 176160ce78 monitor: no need to save need_resume
There is no need for per-command need_resume granularity, it should
resume after running an non-oob command on oob-disabled monitor.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180829134043.31706-5-marcandre.lureau@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-08-30 16:08:54 +02:00
Marc-André Lureau 27656018d8 Revert "qmp: isolate responses into io thread"
This reverts commit abe3cd0ff7.

There is no need to add an additional queue to send the reply to the
IOThread, because QMP response is thread safe, and chardev write path
is thread safe. It will schedule the watcher in the associated
IOThread.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180829134043.31706-4-marcandre.lureau@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-08-30 16:08:51 +02:00
Marc-André Lureau 6cd112e266 monitor: consitify qmp_send_response() QDict argument
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180829134043.31706-2-marcandre.lureau@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-08-30 16:08:42 +02:00
Marc-André Lureau 8af6bb14a3 monitor: accept input on resume
A chardev may stop trying to write if the associated can_read()
callback returned 0. This happens when the monitor is suspended.
The frontend is supposed to call qemu_chr_fe_accept_input() when it is
ready to accept data again.

An issue was observed with a spice port: pending commands may be
delayed, as the chardev is not flushed. Most chardev don't use the
accept_input() callback, and instead check regularly if they can
write. The ones that do use it are braille, mux, msmouse,
spice (abstract), spicevmc, spiceport, wctablet.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20180817173752.19136-1-marcandre.lureau@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-08-28 21:11:06 +02:00
Peter Xu 3ab72385b2 qapi: Drop qapi_event_send_FOO()'s Error ** argument
The generated qapi_event_send_FOO() take an Error ** argument.  They
can't actually fail, because all they do with the argument is passing it
to functions that can't fail: the QObject output visitor, and the
@qmp_emit callback, which is either monitor_qapi_event_queue() or
event_test_emit().

Drop the argument, and pass &error_abort to the QObject output visitor
and @qmp_emit instead.

Suggested-by: Eric Blake <eblake@redhat.com>
Suggested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180815133747.25032-4-peterx@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Commit message rewritten, update to qapi-code-gen.txt corrected]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-08-28 18:21:38 +02:00
Peter Xu 3d7a1c44e2 monitor: simplify monitor_qmp_setup_handlers_bh
When we reach monitor_qmp_setup_handlers_bh() we must be using the
IOThread then, so no need to check against it any more.  Instead, we
assert.

Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180815133747.25032-2-peterx@redhat.com>
[Insufficiently useful comment dropped]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-08-28 18:03:07 +02:00
Markus Armbruster 86cdf9ec8d json: Clean up headers
The JSON parser has three public headers, json-lexer.h, json-parser.h,
json-streamer.h.  They all contain stuff that is of no interest
outside qobject/json-*.c.

Collect the public interface in include/qapi/qmp/json-parser.h, and
everything else in qobject/json-parser-int.h.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-54-armbru@redhat.com>
2018-08-24 20:26:37 +02:00
Markus Armbruster 84a56f38b2 json: Pass lexical errors and limit violations to callback
The callback to consume JSON values takes QObject *json, Error *err.
If both are null, the callback is supposed to make up an error by
itself.  This sucks.

qjson.c's consume_json() neglects to do so, which makes
qobject_from_json() null instead of failing.  I consider that a bug.

The culprit is json_message_process_token(): it passes two null
pointers when it runs into a lexical error or a limit violation.  Fix
it to pass a proper Error object then.  Update the callbacks:

* monitor.c's handle_qmp_command(): the code to make up an error is
  now dead, drop it.

* qga/main.c's process_event(): lumps the "both null" case together
  with the "not a JSON object" case.  The former is now gone.  The
  error message "Invalid JSON syntax" is misleading for the latter.
  Improve it to "Input must be a JSON object".

* qobject/qjson.c's consume_json(): no update; check-qjson
  demonstrates qobject_from_json() now sets an error on lexical
  errors, but still doesn't on some other errors.

* tests/libqtest.c's qmp_response(): the Error object is now reliable,
  so use it to improve the error message.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-40-armbru@redhat.com>
2018-08-24 20:26:37 +02:00
Markus Armbruster 62815d85ae json: Redesign the callback to consume JSON values
The classical way to structure parser and lexer is to have the client
call the parser to get an abstract syntax tree, the parser call the
lexer to get the next token, and the lexer call some function to get
input characters.

Another way to structure them would be to have the client feed
characters to the lexer, the lexer feed tokens to the parser, and the
parser feed abstract syntax trees to some callback provided by the
client.  This way is more easily integrated into an event loop that
dispatches input characters as they arrive.

Our JSON parser is kind of between the two.  The lexer feeds tokens to
a "streamer" instead of a real parser.  The streamer accumulates
tokens until it got the sequence of tokens that comprise a single JSON
value (it counts curly braces and square brackets to decide).  It
feeds those token sequences to a callback provided by the client.  The
callback passes each token sequence to the parser, and gets back an
abstract syntax tree.

I figure it was done that way to make a straightforward recursive
descent parser possible.  "Get next token" becomes "pop the first
token off the token sequence".  Drawback: we need to store a complete
token sequence.  Each token eats 13 + input characters + malloc
overhead bytes.

Observations:

1. This is not the only way to use recursive descent.  If we replaced
   "get next token" by a coroutine yield, we could do without a
   streamer.

2. The lexer reports errors by passing a JSON_ERROR token to the
   streamer.  This communicates the offending input characters and
   their location, but no more.

3. The streamer reports errors by passing a null token sequence to the
   callback.  The (already poor) lexical error information is thrown
   away.

4. Having the callback receive a token sequence duplicates the code to
   convert token sequence to abstract syntax tree in every callback.

5. Known bug: the streamer silently drops incomplete token sequences.

This commit rectifies 4. by lifting the call of the parser from the
callbacks into the streamer.  Later commits will address 3. and 5.

The lifting removes a bug from qjson.c's parse_json(): it passed a
pointer to a non-null Error * in certain cases, as demonstrated by
check-qjson.c.

json_parser_parse() is now unused.  It's a stupid wrapper around
json_parser_parse_err().  Drop it, and rename json_parser_parse_err()
to json_parser_parse().

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-35-armbru@redhat.com>
2018-08-24 20:26:37 +02:00