With bitset management now it becomes feasible to implement
the logic of detaching frontends from multiplexer.
Signed-off-by: Roman Penyaev <r.peniaev@gmail.com>
Cc: "Marc-André Lureau" <marcandre.lureau@redhat.com>
Cc: qemu-devel@nongnu.org
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-ID: <20241014152408.427700-8-r.peniaev@gmail.com>
Frontends can be attached and detached during run-time (although detach
is not implemented, but will follow). Counter variable of muxes is not
enough for proper attach/detach management, so this patch implements
bitset: if bit is set for the `mux_bitset` variable, then frontend
device can be found in the `backend` array (yes, huge confusion with
backend and frontends names).
Signed-off-by: Roman Penyaev <r.peniaev@gmail.com>
Cc: "Marc-André Lureau" <marcandre.lureau@redhat.com>
Cc: qemu-devel@nongnu.org
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-ID: <20241014152408.427700-7-r.peniaev@gmail.com>
Move away logic which attaches frontend device to a mux
from `char-fe.c` to actual `char-mux.c` implementation
and make it a separate function.
No logic changes are made.
Signed-off-by: Roman Penyaev <r.peniaev@gmail.com>
Cc: "Marc-André Lureau" <marcandre.lureau@redhat.com>
Cc: qemu-devel@nongnu.org
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-ID: <20241014152408.427700-6-r.peniaev@gmail.com>
There is no sense to keep `focus`, `mux_cnt`, `prod`, `cons`
and `tag` variables as signed, those represent either size,
either position in array, which both are unsigned.
`focus` member of `MuxChardev` is kept signed, because initially
set to -1.
Signed-off-by: Roman Penyaev <r.peniaev@gmail.com>
Cc: "Marc-André Lureau" <marcandre.lureau@redhat.com>
Cc: qemu-devel@nongnu.org
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-ID: <20241014152408.427700-5-r.peniaev@gmail.com>
Those are boolean variables, not signed integers.
Signed-off-by: Roman Penyaev <r.peniaev@gmail.com>
Cc: "Marc-André Lureau" <marcandre.lureau@redhat.com>
Cc: qemu-devel@nongnu.org
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-ID: <20241014152408.427700-4-r.peniaev@gmail.com>
While there are a number of uses in the code-base of the exit(0)
pattern it gets in the way of clean exit which can do all of it's
house-keeping. In particular it was reported that you can crash
plugins this way because TCG can still be running on other threads
when the atexit callback is called.
Use qmp_quit() instead which takes care of some housekeeping before
triggering the shutdown.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reported-by: Lukas Jünger <lukas.junger@greensocs.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20211026102234.3961636-19-alex.bennee@linaro.org>
"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>
Stop including sysemu/sysemu.h in files that don't need it.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210416171314.2074665-2-thuth@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
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>
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>
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>
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>
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>
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>
Commit fb5e19d2e1 originally fixed the
regression, but was inadvertently broken again in merge commit
2d6752d38d.
Fixes:
https://bugs.launchpad.net/qemu/+bug/1654137
Cc: qemu-stable@nongnu.org
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20180515152500.19460-3-f4bug@amsat.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This reverts commit 1b2503fcf7.
Unfortunately this fix regresses console handling on MIPS Malta;
since the mux ctrl-a b bug is not a regression since 2.11, we
take the conservative approach and just drop it from 2.12.
Reported-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
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>
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]
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>
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>
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>
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>
mux_chr_event() already send events to all backends, rename it,
export it, and use it from muxes_realize_done. This should help abstract
away mux implementation.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
A mechanical move, except that qemu_chr_write_all() needs to be declared
in char.h header to be used from chardev unit files.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
