Commit Graph

48 Commits

Author SHA1 Message Date
Marc-André Lureau
3e301c8d7e ui/dbus: add chardev backend & interface
Add a new chardev backend which allows D-Bus client to handle the
chardev stream & events.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
2021-12-21 10:50:22 +04:00
Marc-André Lureau
fa670c808a chardev: make socket derivable
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2021-12-21 10:50:22 +04:00
Marc-André Lureau
78e3e1d046 chardev: add some comments about the class methods
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210804154848.557328-5-marcandre.lureau@redhat.com>
2021-09-14 16:57:11 +04:00
Marc-André Lureau
5eed493d01 chardev: remove needless class method
"chr_option_parsed" is only implemented by the "mux" chardev, we can
specialize the code there to avoid the needless generic class method.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2021-09-14 16:53:55 +04:00
Marc-André Lureau
bf7b1eab25 chardev: mark explicitly first argument as poisoned
Since commit 9894dc0cdc "char: convert
from GIOChannel to QIOChannel", the first argument to the watch callback
can actually be a QIOChannel, which is not a GIOChannel (but a QEMU
Object).

Even though we never used that pointer, change the callback type to warn
the users. Possibly a better fix later, we may want to store the
callback and call it from intermediary functions.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2021-08-05 16:15:33 +04:00
Lukas Straub
feb774ca3f chardev: Fix yank with the chardev-change case
When changing from chardev-socket (which supports yank) to
chardev-socket again, it fails, because the new chardev attempts
to register a new yank instance. This in turn fails, as there
still is the yank instance from the current chardev. Also,
the old chardev shouldn't unregister the yank instance when it
is freed.

To fix this, now the new chardev only registers a yank instance if
the current chardev doesn't support yank and thus hasn't registered
one already. Also, when the old chardev is freed, it now only
unregisters the yank instance if the new chardev doesn't need it.

If the initialization of the new chardev fails, it still has
chr->handover_yank_instance set and won't unregister the yank
instance when it is freed.

s->registered_yank is always true here, as chardev-change only works
on user-visible chardevs and those are guraranteed to register a
yank instance as they are initialized via
chardev_new()
 qemu_char_open()
  cc->open() (qmp_chardev_open_socket()).

Signed-off-by: Lukas Straub <lukasstraub2@web.de>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Tested-by: Li Zhang <li.zhang@cloud.ionos.com>
Message-Id: <9637888d7591d2971975188478bb707299a1dc04.1617127849.git.lukasstraub2@web.de>
2021-04-01 15:27:44 +04:00
Paolo Bonzini
5a1ee6077b chardev: do not use machine_init_done
machine_init_done is not the right flag to check when preconfig
is taken into account; for example "./qemu-system-x86_64 -serial
mon:stdio -preconfig" does not print the QEMU monitor header until after
exit_preconfig.  Add back a custom bool for mux character devices.  This
partially undoes commit c7278b4355 ("chardev: introduce chr_machine_done
hook", 2018-03-12), but it keeps the cleaner logic using a function
pointer in ChardevClass.

Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-15 12:51:51 -05:00
Gerd Hoffmann
93ab5844b2 chardev/spice: simplify chardev setup
Initialize spice before chardevs.  That allows to register the spice
chardevs directly in the init function and removes the need to maintain
a linked list of chardevs just for registration.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-id: 20201014121120.13482-5-kraxel@redhat.com
2020-10-15 11:14:40 +02:00
Gerd Hoffmann
70122d6230 chardev/spice: make qemu_chr_open_spice_port static
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20201014121120.13482-4-kraxel@redhat.com
2020-10-15 11:14:40 +02:00
Eduardo Habkost
a489d1951c Use OBJECT_DECLARE_TYPE when possible
This converts existing DECLARE_OBJ_CHECKERS usage to
OBJECT_DECLARE_TYPE when possible.

 $ ./scripts/codeconverter/converter.py -i \
   --pattern=AddObjectDeclareType $(git grep -l '' -- '*.[ch]')

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Acked-by: Paul Durrant <paul@xen.org>
Message-Id: <20200916182519.415636-5-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2020-09-18 14:12:32 -04:00
Eduardo Habkost
8110fa1d94 Use DECLARE_*CHECKER* macros
Generated using:

 $ ./scripts/codeconverter/converter.py -i \
   --pattern=TypeCheckMacro $(git grep -l '' -- '*.[ch]')

Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20200831210740.126168-12-ehabkost@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20200831210740.126168-13-ehabkost@redhat.com>
Message-Id: <20200831210740.126168-14-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2020-09-09 09:27:09 -04:00
Eduardo Habkost
db1015e92e Move QOM typedefs and add missing includes
Some typedefs and macros are defined after the type check macros.
This makes it difficult to automatically replace their
definitions with OBJECT_DECLARE_TYPE.

Patch generated using:

 $ ./scripts/codeconverter/converter.py -i \
   --pattern=QOMStructTypedefSplit $(git grep -l '' -- '*.[ch]')

which will split "typdef struct { ... } TypedefName"
declarations.

Followed by:

 $ ./scripts/codeconverter/converter.py -i --pattern=MoveSymbols \
    $(git grep -l '' -- '*.[ch]')

which will:
- move the typedefs and #defines above the type check macros
- add missing #include "qom/object.h" lines if necessary

Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20200831210740.126168-9-ehabkost@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20200831210740.126168-10-ehabkost@redhat.com>
Message-Id: <20200831210740.126168-11-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2020-09-09 09:26:43 -04:00
Philippe Mathieu-Daudé
ffa0f7eb57 chardev: Reduce "char-mux.h" scope, rename it "chardev-internal.h"
No file out of chardev/ requires access to this header,
restrict its scope.

Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200423202112.644-5-philmd@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
2020-07-13 11:59:47 +04:00
Philippe Mathieu-Daudé
083b266f69 chardev: Use QEMUChrEvent enum in IOEventHandler typedef
The Chardev events are listed in the QEMUChrEvent enum.

By using the enum in the IOEventHandler typedef we:

- make the IOEventHandler type more explicit (this handler
  process out-of-band information, while the IOReadHandler
  is in-band),
- help static code analyzers.

This patch was produced with the following spatch script:

  @match@
  expression backend, opaque, context, set_open;
  identifier fd_can_read, fd_read, fd_event, be_change;
  @@
  qemu_chr_fe_set_handlers(backend, fd_can_read, fd_read, fd_event,
                           be_change, opaque, context, set_open);

  @depends on match@
  identifier opaque, event;
  identifier match.fd_event;
  @@
   static
  -void fd_event(void *opaque, int event)
  +void fd_event(void *opaque, QEMUChrEvent event)
   {
   ...
   }

Then the typedef was modified manually in
include/chardev/char-fe.h.

Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: Corey Minyard <cminyard@mvista.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20191218172009.8868-15-philmd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-08 11:15:35 +01:00
Paolo Bonzini
2fa9044a4f chardev: use QEMUChrEvent instead of int
This uses the QEMUChrEvent enum everywhere except in IOEventHandler.
The IOEventHandler change needs to happen at once for all front ends and
is done with Coccinelle in the next patch.

(Extracted from a patch by Philippe Mathieu-Daudé).

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-01-08 11:14:49 +01:00
Markus Armbruster
db72581598 Include qemu/main-loop.h less
In my "build everything" tree, changing qemu/main-loop.h triggers a
recompile of some 5600 out of 6600 objects (not counting tests and
objects that don't depend on qemu/osdep.h).  It includes block/aio.h,
which in turn includes qemu/event_notifier.h, qemu/notify.h,
qemu/processor.h, qemu/qsp.h, qemu/queue.h, qemu/thread-posix.h,
qemu/thread.h, qemu/timer.h, and a few more.

Include qemu/main-loop.h only where it's needed.  Touching it now
recompiles only some 1700 objects.  For block/aio.h and
qemu/event_notifier.h, these numbers drop from 5600 to 2800.  For the
others, they shrink only slightly.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190812052359.30071-21-armbru@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2019-08-16 13:31:52 +02:00
Markus Armbruster
a8d2532645 Include qemu-common.h exactly where needed
No header includes qemu-common.h after this commit, as prescribed by
qemu-common.h's file comment.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190523143508.25387-5-armbru@redhat.com>
[Rebased with conflicts resolved automatically, except for
include/hw/arm/xlnx-zynqmp.h hw/arm/nrf51_soc.c hw/arm/msf2-soc.c
block/qcow2-refcount.c block/qcow2-cluster.c block/qcow2-cache.c
target/arm/cpu.h target/lm32/cpu.h target/m68k/cpu.h target/mips/cpu.h
target/moxie/cpu.h target/nios2/cpu.h target/openrisc/cpu.h
target/riscv/cpu.h target/tilegx/cpu.h target/tricore/cpu.h
target/unicore32/cpu.h target/xtensa/cpu.h; bsd-user/main.c and
net/tap-bsd.c fixed up]
2019-06-12 13:20:20 +02:00
Markus Armbruster
a8b991b52d Clean up ill-advised or unusual header guards
Leading underscores are ill-advised because such identifiers are
reserved.  Trailing underscores are merely ugly.  Strip both.

Our header guards commonly end in _H.  Normalize the exceptions.

Done with scripts/clean-header-guards.pl.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190315145123.28030-7-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
[Changes to slirp/ dropped, as we're about to spin it off]
2019-05-13 08:58:55 +02:00
Marc-André Lureau
24fa7da3ca char: move SpiceChardev and open_spice_port() to spice.h header
This will allow easier subclassing of SpiceChardev, in upcoming
"display: add -display spice-app launching external application"
patch.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Tested-by: Victor Toso <victortoso@redhat.com>
Message-id: 20190221110703.5775-7-marcandre.lureau@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2019-02-21 14:09:17 +01:00
Marc-André Lureau
64c3f266dd chardev: add a note about frontend sources and context switch
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20190206174328.9736-5-marcandre.lureau@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
2019-02-13 16:46:39 +01:00
Marc-André Lureau
3d9e232240 char: update the mux handlers in class callback
Instead of handling mux chardev in a special way in
qemu_chr_fe_set_handlers(), we may use the chr_update_read_handler
class callback instead.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20190206174328.9736-2-marcandre.lureau@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
2019-02-13 15:36:14 +01:00
Paolo Bonzini
4ad6f6cb14 char: allow specifying a GMainContext at opening time
This will be needed by vhost-user-test, when each test switches to
its own GMainLoop and GMainContext.  Otherwise, for a reconnecting
socket the initial connection will happen on the default GMainContext,
and no one will be listening on it.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20190202110834.24880-1-pbonzini@redhat.com>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
2019-02-13 14:23:39 +01:00
Artem Pisarenko
7a9657ef53 chardev: fix mess in OPENED/CLOSED events when muxed
When chardev is multiplexed (mux=on) there are a lot of cases where
CHR_EVENT_OPENED/CHR_EVENT_CLOSED events pairing (expected from
frontend side) is broken. There are either generation of multiple
repeated or extra CHR_EVENT_OPENED events, or CHR_EVENT_CLOSED just
isn't generated at all.
This is mostly because 'qemu_chr_fe_set_handlers()' function makes its
own (and often wrong) implicit decision on updated frontend state and
invokes 'fd_event' callback with 'CHR_EVENT_OPENED'. And even worse,
it doesn't do symmetric action in opposite direction, as someone may
expect (i.e. it doesn't invoke previously set 'fd_event' with
'CHR_EVENT_CLOSED'). Muxed chardev uses trick by calling this function
again to replace callback handlers with its own ones, but it doesn't
account for such side effect.
Fix that using extended version of this function with added argument
for disabling side effect and keep original function for compatibility
with lots of frontends already using this interface and being
"tolerant" to its side effects.
One more source of event duplication is just line of code in
char-mux.c, which does far more than comment above says (obvious fix).

Signed-off-by: Artem Pisarenko <artem.k.pisarenko@gmail.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <7dde6abbd21682857f8294644013173c0b9949b3.1541507990.git.artem.k.pisarenko@gmail.com>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
2019-02-12 17:35:56 +01:00
Marc-André Lureau
9ac3788b0b char: add a QEMU_CHAR_FEATURE_GCONTEXT flag
QEMU_CHAR_FEATURE_GCONTEXT declares the character device can switch
GMainContext.

Assert we don't switch context when the character device doesn't
provide this feature.  Character device users must not violate this
restriction.  In particular, user configurations that violate them
must be rejected.

Existing frontend that rely on context switching would now assert() if
the backend doesn't allow it (instead of silently producing undesired
events in the default context). Following patches improve the
situation by reporting an error earlier instead, on the frontend side.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20181205203737.9011-4-marcandre.lureau@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-12-12 09:55:57 +01:00
Marc-André Lureau
95e30b2a13 chardev: mark the calls that allow an implicit mux monitor
This is mostly for readability of the code. Let's make it clear which
callers can create an implicit monitor when the chardev is muxed.

This will also enforce a safer behaviour, as we don't really support
creating monitor anywhere/anytime at the moment. Add an assert() to
make sure the programmer explicitely wanted that behaviour.

There are documented cases, such as: -serial/-parallel/-virtioconsole
and to less extent -debugcon.

Less obvious and questionable ones are -gdb, SLIRP -guestfwd and Xen
console. Add a FIXME note for those, but keep the support for now.

Other qemu_chr_new() callers either have a fixed parameter/filename
string or do not need it, such as -qtest:

* qtest.c: qtest_init()
  Afaik, only used by tests/libqtest.c, without mux. I don't think we
  support it outside of qemu testing: drop support for implicit mux
  monitor (qemu_chr_new() call: no implicit mux now).

* hw/
  All with literal @filename argument that doesn't enable mux monitor.

* tests/
  All with @filename argument that doesn't enable mux monitor.

On a related note, the list of monitor creation places:

- the chardev creators listed above: all from command line (except
  perhaps Xen console?)

- -gdb & hmp gdbserver will create a "GDB monitor command" chardev
  that is wired to an HMP monitor.

- -mon command line option

From this short study, I would like to think that a monitor may only
be created in the main thread today, though I remain skeptical :)

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
2018-10-03 14:45:05 +04:00
Marc-André Lureau
5662576ad0 char.h: fix gtk-doc comment style
Fix up conformance to GTK-Doc function comment style, as documented in
https://developer.gnome.org/gtk-doc-manual/stable/documenting_symbols.html.en

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
2018-10-03 14:45:05 +04:00
Julia Suvorova
7351681ec2 chardev/char-fe: Fix typos
Fixup some typos in the comments.

Signed-off-by: Julia Suvorova <jusual@mail.ru>
Message-Id: <20180813093402.10852-1-jusual@mail.ru>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-08-23 13:32:50 +02:00
Peter Xu
d88610111b chardev: comment details for CLOSED event
It was unclear before on what does the CLOSED event mean.  Meanwhile we
add a TODO to fix up the CLOSED event in the future when the in/out
ports are different for a chardev.

CC: Paolo Bonzini <pbonzini@redhat.com>
CC: "Marc-André Lureau" <marcandre.lureau@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180620073223.31964-2-peterx@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-06-30 17:50:48 +02:00
Peter Xu
c7278b4355 chardev: introduce chr_machine_done hook
Introduce ChardevClass.chr_machine_done() hook so that chardevs can run
customized procedures after machine init.

There was an existing mux user already that did similar thing but used a
raw machine done notifier.  Generalize it into a framework, and let the
mux chardevs provide such a class-specific hook to achieve the same
thing.  Then we can move the mux related code to the char-mux.c file.

Since at it, replace the mux_realized variable with the global
machine_init_done varible.

This notifier framework will be further leverged by other type of
chardevs soon.

Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180306053320.15401-6-peterx@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-03-12 16:12:46 +01:00
Markus Armbruster
9af2398977 Include less of the generated modular QAPI headers
In my "build everything" tree, a change to the types in
qapi-schema.json triggers a recompile of about 4800 out of 5100
objects.

The previous commit split up qmp-commands.h, qmp-event.h, qmp-visit.h,
qapi-types.h.  Each of these headers still includes all its shards.
Reduce compile time by including just the shards we actually need.

To illustrate the benefits: adding a type to qapi/migration.json now
recompiles some 2300 instead of 4800 objects.  The next commit will
improve it further.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180211093607.27351-24-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
[eblake: rebase to master]
Signed-off-by: Eric Blake <eblake@redhat.com>
2018-03-02 13:45:50 -06:00
Markus Armbruster
922a01a013 Move include qemu/option.h from qemu-common.h to actual users
qemu-common.h includes qemu/option.h, but most places that include the
former don't actually need the latter.  Drop the include, and add it
to the places that actually need it.

While there, drop superfluous includes of both headers, and
separate #include from file comment with a blank line.

This cleanup makes the number of objects depending on qemu/option.h
drop from 4545 (out of 4743) to 284 in my "build everything" tree.

Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-20-armbru@redhat.com>
[Semantic conflict with commit bdd6a90a9e in block/nvme.c resolved]
2018-02-09 13:52:16 +01:00
Peter Xu
2c716ba150 chardev: introduce qemu_chr_timeout_add_ms()
It's a replacement of g_timeout_add[_seconds]() for chardevs.  Chardevs
now can have dedicated gcontext, we should always bind chardev tasks
onto those gcontext rather than the default main context.  Since there
are quite a few of g_timeout_add[_seconds]() callers, a new function
qemu_chr_timeout_add_ms() is introduced.

One thing to mention is that, terminal3270 is still always running on
main gcontext.  However let's convert that as well since it's still part
of chardev codes and in case one day we'll miss that when we move it out
of main gcontext too.

Also, convert all the timers from GSource tags into GSource pointers.
Gsource tag IDs and g_source_remove()s can only work with default
gcontext, while now these GSources can logically be attached to other
contexts.  So let's use explicit g_source_destroy() plus another
g_source_unref() to remove a timer.

Note: when in the timer handler, we don't need the g_source_destroy()
any more since that'll be done automatically if the timer handler
returns false (and that's what all the current handlers do).

Yet another note: in pty_chr_rearm_timer() we take special care for
ms=1000.  This patch merged the two cases into one.

Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180104141835.17987-4-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-01-12 13:22:02 +01:00
Marc-André Lureau
d09c4a4787 chardev: fix backend events regression with mux chardev
Kirill noticied that on recent versions on QEMU he was not able to
trigger SysRq to invoke debug capabilites of Linux Kernel.  He tracked
it down to qemu_chr_be_event() ignoring CHR_EVENT_BREAK due s->be
being NULL. The bug was introduced in 2.8, commit a4afa548fc ("char:
move front end handlers in CharBackend"). Since the commit, the
qemu_chr_be_event() failed to deliver CHR_EVENT_BREAK due to
qemu_chr_fe_init() does not set s->be in case of mux.

Let's fix this by teaching mux to send an event to the frontend with
the focus.

Reported-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Fixes: a4afa548fc ("char: move front end handlers in CharBackend")
Message-Id: <20171103152824.21948-2-marcandre.lureau@redhat.com>
Tested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-12-21 09:30:32 +01:00
Peter Xu
bb86d05f4a chardev: remove context in chr_update_read_handler
We had a per-chardev cache for context, then we don't need this
parameter to be passed in every time when chr_update_read_handler()
called.  As long as we are calling chr_update_read_handler() using
qemu_chr_be_update_read_handlers() we'll be fine.

Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <1505975754-21555-5-git-send-email-peterx@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-09-22 21:07:27 +02:00
Peter Xu
95eeeba669 chardev: add Chardev.gcontext field
It caches the gcontext that is used to poll the chardev IO.  Before this
patch, we only passed it in via chr_update_read_handlers().  However
that may not be enough if the char backend is disconnected and
reconnected afterward.  There are chardev codes that still assumed the
context be NULL (which is the main context).  Will fix that up in
following up patches.

Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <1505975754-21555-3-git-send-email-peterx@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-09-22 21:07:27 +02:00
Peter Xu
07241c205c chardev: new qemu_chr_be_update_read_handlers()
Add a wrapper for the chr_update_read_handler().

Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <1505975754-21555-2-git-send-email-peterx@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-09-22 21:07:27 +02:00
Anton Nefedov
0ec846bfac char: don't exit on hmp 'chardev-add help'
qemu_chr_new_from_opts() is used from both vl.c and hmp,
and it is quite confusing to see qemu suddenly exit after receiving a help
option in hmp.

Do exit(0) from vl.c instead.

Signed-off-by: Anton Nefedov <anton.nefedov@virtuozzo.com>
Message-Id: <1500977081-120929-1-git-send-email-anton.nefedov@virtuozzo.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-08-01 17:27:33 +02:00
Marc-André Lureau
4db0db1fa6 char-fd: remove useless chr pointer
Apparently unused since it was introduced in commit
a29753f8aa. Now, it can be trivially
accessed by CHARDEV() of self.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20170720100046.4424-1-marcandre.lureau@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-08-01 17:27:33 +02:00
Anton Nefedov
75b601602b hmp: add hmp analogue for qmp-chardev-change
Signed-off-by: Anton Nefedov <anton.nefedov@virtuozzo.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Acked-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <1499342940-56739-11-git-send-email-anton.nefedov@virtuozzo.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-07-14 11:04:34 +02:00
Anton Nefedov
3065070153 char: avoid chardevice direct access
frontends should avoid accessing CharDriver struct where possible

Signed-off-by: Anton Nefedov <anton.nefedov@virtuozzo.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <1499342940-56739-6-git-send-email-anton.nefedov@virtuozzo.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-07-14 11:04:33 +02:00
Anton Nefedov
7c44a2a9d1 char: forbid direct chardevice access for hotswap devices
qemu_chr_fe_get_driver() is unsafe, frontends with hotswap support
should not access CharDriver ptr directly as CharDriver might change.

Signed-off-by: Anton Nefedov <anton.nefedov@virtuozzo.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <1499342940-56739-5-git-send-email-anton.nefedov@virtuozzo.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-07-14 11:04:33 +02:00
Anton Nefedov
7bb86085e6 char: chardevice hotswap
This patch adds a possibility to change a char device without a frontend
removal.

Ideally, it would have to happen transparently to a frontend, i.e.
frontend would continue its regular operation.
However, backends are not stateless and are set up by the frontends
via qemu_chr_fe_<> functions, and it's not (generally) possible to replay
that setup entirely in a backend code, as different chardevs respond
to the setup calls differently, so do frontends work differently basing
on those setup responses.
Moreover, some frontend can generally get and save the backend pointer
(qemu_chr_fe_get_driver()), and it will become invalid after backend change.

So, a frontend which would like to support chardev hotswap has to register
a "backend change" handler, and redo its backend setup there.

Signed-off-by: Anton Nefedov <anton.nefedov@virtuozzo.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <1499342940-56739-4-git-send-email-anton.nefedov@virtuozzo.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-07-14 11:04:33 +02:00
Anton Nefedov
81517ba37a char: add backend hotswap handler
Frontends should have an interface to setup the handler of a backend change.
The interface will be used in the next commits

Signed-off-by: Anton Nefedov <anton.nefedov@virtuozzo.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <1499342940-56739-3-git-send-email-anton.nefedov@virtuozzo.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-07-14 11:04:33 +02:00
Marc-André Lureau
d203c64398 char: fix alias devices regression
Fix regression from commit 4d43a603c7, where the serial and parallel
headers got removed from char.c, which broke the alias table.

Move the HAVE_CHARDEV_SERIAL/HAVE_CHARDEV_PARPORT to osdep.h instead
of being in separate headers.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2017-06-08 17:57:36 +04:00
Marc-André Lureau
1ce2610c10 char: make chr_fe_deinit() optionaly delete backend
This simplifies removing a backend for a frontend user (no need to
retrieve the associated driver and separate delete call etc).

NB: many frontends have questionable handling of ending a chardev. They
should probably delete the backend to prevent broken reusage.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2017-06-02 11:33:53 +04:00
Marc-André Lureau
4d43a603c7 char: move CharBackend handling in char-fe unit
Move all the frontend struct and methods to a seperate unit. This avoids
accidentally mixing backend and frontend calls, and helps with readabilty.

Make qemu_chr_replay() a macro shared by both char and char-fe.

Export qemu_chr_write(), and use a macro for qemu_chr_write_all()

(nb: yes, CharBackend is for char frontend :)

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2017-06-02 11:33:53 +04:00
Marc-André Lureau
7566c6efe7 chardev: serial & parallel declaration to own headers
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2017-06-02 11:33:52 +04:00
Marc-André Lureau
8228e353d8 chardev: move headers to include/chardev
So they are all in one place. The following patch will move serial &
parallel declarations to the respective headers.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2017-06-02 11:33:52 +04:00