The previous patch left in an extra scope layer for ease of
review; time to remove it. No semantic change.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20171201232433.25193-5-eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Use of a do/while(0) control flow in order to permit an early break
is an unusual paradigm, and triggers a false positive with a planned
future syntax check against 'while (0);'. Rewrite the code to use a
goto instead. This patch temporarily keeps an extra level of
indentation to highlight the change; the next patch cleans it up.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20171201232433.25193-4-eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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>
The idle task will be attached to main gcontext even if the chardev
backend is running in another gcontext. Fix the only caller by
extending the g_idle_add() logic into the more powerful
g_source_attach(). It's basically g_idle_add_full() implementation, but
with the chardev's gcontext passed in.
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180104141835.17987-3-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In commit 6bbb6c0644 ("chardev: use per-dev context for
io_add_watch_poll", 2017-09-22) all the chardev watches are converted to
use per-chardev gcontext to support chardev to be run outside default
main thread. However that's still missing one call from the frontend
code. Touch that up.
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180104141835.17987-2-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Instead of creating a QIOChannelSocket directly for the chardev
server socket, use a QIONetListener. This provides the ability
to listen on multiple sockets at the same time, so enables
full support for IPv4/IPv6 dual stack.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <20171218135417.28301-2-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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>
Baum device bigger than 84 do not actually exist, but the user's own
Braille device might be wider than 84 columns. Some guest drivers
would be upset by such sizes, so clamp the device size.
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Message-Id: <20171211001950.27843-1-samuel.thibault@ens-lyon.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
applied using ./scripts/clean-includes
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Ben Warren <ben@skyportsystems.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
The tcp_chr_free_connection & tcp_chr_disconnect methods both
skip all of their cleanup work unless the 's->connected' flag
is set. This flag is set when the incoming client connection
is ready to use. Crucially this is *after* the TLS handshake
has been completed. So if the TLS handshake fails and we try
to cleanup the failed client, all the cleanup is skipped as
's->connected' is still false.
The only important thing that should be skipped in this case
is sending of the CHR_EVENT_CLOSED, because we never got as
far as sending the corresponding CHR_EVENT_OPENED. Every other
bit of cleanup can be robust against being called even when
s->connected is false.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <20171005155057.7664-1-berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Error process of baum_chr_open needs to set brlapi null, so it won't
get released twice in char_braille_finalize, which will cause
"/usr/bin/qemu-system-x86_64: double free or corruption (!prev)"
Signed-off-by: Liang Yan <lyan@suse.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
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>
It was only passed in by chr_update_read_handlers(). However when
reconnect, we'll lose that context information. So if a chardev was
running on another context (rather than the default context, the NULL
pointer), it'll switch back to the default context if reconnection
happens. But, it should really stick to the old context.
Convert all the callers of io_add_watch_poll() to use the internally
cached gcontext. Then the context should be able to survive even after
reconnections.
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <1505975754-21555-4-git-send-email-peterx@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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>
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>
baum.o already receives the sdl cflags in its per object variable, do
the same for brlapi libs to avoid cluttering libs_softmmu.
Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <20170907084700.952-1-famz@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
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>
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>
With the move of some docs/ to docs/devel/ on ac06724a71,
no references were updated.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
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>
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>
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>
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>
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>
parse function will be used by the following patch
Signed-off-by: Anton Nefedov <anton.nefedov@virtuozzo.com>
Message-Id: <1499342940-56739-2-git-send-email-anton.nefedov@virtuozzo.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When QEMU is waiting for a TCP socket connection it reports that message as
an error. This isn't an error it is just information so let's change the
report to use info_report() instead.
Signed-off-by: Alistair Francis <alistair.francis@xilinx.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <b3f3601c52843afca9a9b12c7a4fefd68e60de32.1499866456.git.alistair.francis@xilinx.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Sending a break on a serial console can be useful for debugging the
guest. But not all chardev backends support sending breaks (only telnet
and mux do). The chardev-send-break command allows to send a break even
if using other backends.
Signed-off-by: Stefan Fritsch <sf@sfritsch.de>
Acked-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20170611074817.13621-1-sf@sfritsch.de>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Use 'send a break' in all 3 pieces of text as suggested by eblake
"parport" is considered "old" since commit 88a946d32d, when "parallel"
was added. Similarly for "tty" in commit d59044ef74.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Suggested by Paolo Bonzini during series review.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
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>
There is no clear reason to have those functions associated with
frontend.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
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>
qemu_chr_fe_write() is similar to qemu_chr_write_all(): the later write
all with a chardev backend.
Make qemu_chr_write() and qemu_chr_fe_write_buffer() take an 'all'
argument. If false, handle 'partial' write the way qemu_chr_fe_write()
use to, and call qemu_chr_write() from qemu_chr_fe_write().
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>
Only the console handle shouldn't be closed, however, the "file" handle
should.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
hcom is the name of the file handle, regardless of the actual chardev
driver (serial, file, console etc..). Rename it to be more explicit.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Those 2 functions are specific to serial chardev, make it more clear.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
The "len" argument can be passed directly to win_chr_read()
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
win_chr_read_poll() is always used before win_chr_read().
We can easily fold win_chr_readfile() too.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
chardev/char.c: In function 'chardev_name_foreach':
chardev/char.c:546:19: error: comparison of unsigned expression < 0 is always false [-Werror=type-limits]
for (i = 0; i < ARRAY_SIZE(chardev_alias_table); i++) {
^
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20170530120919.8874-1-f4bug@amsat.org>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
SocketAddressLegacy is a simple union, and simple unions are awkward:
they have their variant members wrapped in a "data" object on the
wire, and require additional indirections in C. SocketAddress is the
equivalent flat union. Convert all users of SocketAddressLegacy to
SocketAddress, except for existing external interfaces.
See also commit fce5d53..9445673 and 85a82e8..c5f1ae3.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1493192202-3184-7-git-send-email-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[Minor editing accident fixed, commit message and a comment tweaked]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The next commit will rename SocketAddressFlat to SocketAddress, and
the commit after that will replace most uses of SocketAddressLegacy by
SocketAddress, replacing most of this commit's renames right back.
Note that checkpatch emits a few "line over 80 characters" warnings.
The long lines are all temporary; the SocketAddressLegacy replacement
will shorten them again.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1493192202-3184-5-git-send-email-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
but it'll come in the next pull request.
* use GDB XML register description for x86
* use _Static_assert in QEMU_BUILD_BUG_ON
* add "R:" to MAINTAINERS and get_maintainers
* checkpatch improvements
* dump threading fixes
* first part of vhost-user-scsi support
* QemuMutex tracing
* vmw_pvscsi and megasas fixes
* sgabios module update
* use Rev3 (ACPI 2.0) FADT
* deprecate -hdachs
* improve -accel documentation
* hax fix
* qemu-char GSource bugfix
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Merge remote-tracking branch 'bonzini/tags/for-upstream' into staging
A large set of small patches. I have not included yet vhost-user-scsi,
but it'll come in the next pull request.
* use GDB XML register description for x86
* use _Static_assert in QEMU_BUILD_BUG_ON
* add "R:" to MAINTAINERS and get_maintainers
* checkpatch improvements
* dump threading fixes
* first part of vhost-user-scsi support
* QemuMutex tracing
* vmw_pvscsi and megasas fixes
* sgabios module update
* use Rev3 (ACPI 2.0) FADT
* deprecate -hdachs
* improve -accel documentation
* hax fix
* qemu-char GSource bugfix
# gpg: Signature made Fri 05 May 2017 06:10:40 AM EDT
# gpg: using RSA key 0xBFFBD25F78C7AE83
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>"
# gpg: aka "Paolo Bonzini <pbonzini@redhat.com>"
# Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4 E2F7 7E15 100C CD36 69B1
# Subkey fingerprint: F133 3857 4B66 2389 866C 7682 BFFB D25F 78C7 AE83
* bonzini/tags/for-upstream: (21 commits)
vhost-scsi: create a vhost-scsi-common abstraction
libvhost-user: replace vasprintf() to fix build
get_maintainer: add subsystem to reviewer output
get_maintainer: --r (list reviewer) is on by default
get_maintainer: it's '--pattern-depth', not '-pattern-depth'
get_maintainer: Teach get_maintainer.pl about the new "R:" tag
MAINTAINERS: Add "R:" tag for self-appointed reviewers
Fix the -accel parameter and the documentation for 'hax'
dump: Acquire BQL around vm_start() in dump thread
hax: Fix memory mapping de-duplication logic
checkpatch: Disallow glib asserts in main code
trace: add qemu mutex lock and unlock trace events
vmw_pvscsi: check message ring page count at initialisation
sgabios: update for "fix wrong video attrs for int 10h,ah==13h"
scsi: avoid an off-by-one error in megasas_mmio_write
vl: deprecate the "-hdachs" option
use _Static_assert in QEMU_BUILD_BUG_ON
target/i386: Add GDB XML register description support
char: Fix removing wrong GSource that be found by fd_in_tag
hw/i386: Build-time assertion on pc/q35 reset register being identical.
...
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Instead of flushing the buffer byte by byte, call qemu_chr_be_write()
with as much byte possible accepted by the front-end.
Factor out buffer flushing in a common function udp_chr_flush_buffer().
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
