Commit Graph

52 Commits

Author SHA1 Message Date
Marc-André Lureau
82878dac6f char: remove explicit_be_open from CharDriverState
It's only used in qmp_chardev_add(), so use a create() argument instead.

Also switched to typedef functions for CharDriverParse/CharDriverCreate.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20161022100951.19562-7-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-24 15:46:11 +02:00
Marc-André Lureau
58fa54947e char: remove unused qemu_chr_fe_event
I introduced this function in d61b0c9a2f, but it isn't
used. Furthermore, it was incomplete, as it would need to translate QEMU
chr events to Spice port events.

(presumably it was used in the follow-up NBD-spice series that was not
completed: http://lists.gnu.org/archive/html/qemu-devel/2013-11/msg02024.html)

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20161022100951.19562-4-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-24 15:46:10 +02:00
Marc-André Lureau
72ac876248 char: rename chr_close/chr_free
The function is used to free the backend opaque pointer, let's name it
accordingly.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20161022095318.17775-23-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-24 15:46:10 +02:00
Eric Blake
32bafa8fdd qapi: Don't special-case simple union wrappers
Simple unions were carrying a special case that hid their 'data'
QMP member from the resulting C struct, via the hack method
QAPISchemaObjectTypeVariant.simple_union_type().  But by using
the work we started by unboxing flat union and alternate
branches, coupled with the ability to visit the members of an
implicit type, we can now expose the simple union's implicit
type in qapi-types.h:

| struct q_obj_ImageInfoSpecificQCow2_wrapper {
|     ImageInfoSpecificQCow2 *data;
| };
|
| struct q_obj_ImageInfoSpecificVmdk_wrapper {
|     ImageInfoSpecificVmdk *data;
| };
...
| struct ImageInfoSpecific {
|     ImageInfoSpecificKind type;
|     union { /* union tag is @type */
|         void *data;
|-        ImageInfoSpecificQCow2 *qcow2;
|-        ImageInfoSpecificVmdk *vmdk;
|+        q_obj_ImageInfoSpecificQCow2_wrapper qcow2;
|+        q_obj_ImageInfoSpecificVmdk_wrapper vmdk;
|     } u;
| };

Doing this removes asymmetry between QAPI's QMP side and its
C side (both sides now expose 'data'), and means that the
treatment of a simple union as sugar for a flat union is now
equivalent in both languages (previously the two approaches used
a different layer of dereferencing, where the simple union could
be converted to a flat union with equivalent C layout but
different {} on the wire, or to an equivalent QMP wire form
but with different C representation).  Using the implicit type
also lets us get rid of the simple_union_type() hack.

Of course, now all clients of simple unions have to adjust from
using su->u.member to using su->u.member.data; while this touches
a number of files in the tree, some earlier cleanup patches
helped minimize the change to the initialization of a temporary
variable rather than every single member access.  The generated
qapi-visit.c code is also affected by the layout change:

|@@ -7393,10 +7393,10 @@ void visit_type_ImageInfoSpecific_member
|     }
|     switch (obj->type) {
|     case IMAGE_INFO_SPECIFIC_KIND_QCOW2:
|-        visit_type_ImageInfoSpecificQCow2(v, "data", &obj->u.qcow2, &err);
|+        visit_type_q_obj_ImageInfoSpecificQCow2_wrapper_members(v, &obj->u.qcow2, &err);
|         break;
|     case IMAGE_INFO_SPECIFIC_KIND_VMDK:
|-        visit_type_ImageInfoSpecificVmdk(v, "data", &obj->u.vmdk, &err);
|+        visit_type_q_obj_ImageInfoSpecificVmdk_wrapper_members(v, &obj->u.vmdk, &err);
|         break;
|     default:
|         abort();

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1458254921-17042-13-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-03-18 10:29:26 +01:00
Eric Blake
21a933ea33 chardev: Properly initialize ChardevCommon components
Commit d0d7708b forgot to parse logging for spice chardevs and
virtual consoles. This requires making qemu_chr_parse_common()
non-static. While at it, use a temporary variable to make the
code shorter, as well as reduce the churn when a later patch
alters the layout of simple unions.

Signed-off-by: Eric Blake <eblake@redhat.com>
CC: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1455927587-28033-2-git-send-email-eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-25 16:11:29 +01:00
Peter Maydell
d38ea87ac5 all: Clean up includes
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.

This commit was created with scripts/clean-includes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1454089805-5470-16-git-send-email-peter.maydell@linaro.org
2016-02-04 17:41:30 +00:00
Daniel P. Berrange
d0d7708ba2 qemu-char: add logfile facility to all chardev backends
Typically a UNIX guest OS will log boot messages to a serial
port in addition to any graphical console. An admin user
may also wish to use the serial port for an interactive
console. A virtualization management system may wish to
collect system boot messages by logging the serial port,
but also wish to allow admins interactive access.

Currently providing such a feature forces the mgmt app
to either provide 2 separate serial ports, one for
logging boot messages and one for interactive console
login, or to proxy all output via a separate service
that can multiplex the two needs onto one serial port.
While both are valid approaches, they each have their
own downsides. The former causes confusion and extra
setup work for VM admins creating disk images. The latter
places an extra burden to re-implement much of the QEMU
chardev backends logic in libvirt or even higher level
mgmt apps and adds extra hops in the data transfer path.

A simpler approach that is satisfactory for many use
cases is to allow the QEMU chardev backends to have a
"logfile" property associated with them.

 $QEMU -chardev socket,host=localhost,port=9000,\
                server=on,nowait,id-charserial0,\
		logfile=/var/log/libvirt/qemu/test-serial0.log
       -device isa-serial,chardev=charserial0,id=serial0

This patch introduces a 'ChardevCommon' struct which
is setup as a base for all the ChardevBackend types.
Ideally this would be registered directly as a base
against ChardevBackend, rather than each type, but
the QAPI generator doesn't allow that since the
ChardevBackend is a non-discriminated union. The
ChardevCommon struct provides the optional 'logfile'
parameter, as well as 'logappend' which controls
whether QEMU truncates or appends (default truncate).

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1452516281-27519-1-git-send-email-berrange@redhat.com>
[Call qemu_chr_parse_common if cd->parse is NULL. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-01-15 18:58:02 +01:00
Eric Blake
130257dc44 char: Convert to new qapi union layout
We have two issues with our qapi union layout:
1) Even though the QMP wire format spells the tag 'type', the
C code spells it 'kind', requiring some hacks in the generator.
2) The C struct uses an anonymous union, which places all tag
values in the same namespace as all non-variant members. This
leads to spurious collisions if a tag value matches a non-variant
member's name.

Make the conversion to the new layout for character-related
code.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1445898903-12082-19-git-send-email-eblake@redhat.com>
[Commit message tweaked slightly]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-11-02 08:30:27 +01:00
Paolo Bonzini
68145e178a qemu-char: convert spice backend to data-driven creation
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-19 10:13:07 +02:00
Paolo Bonzini
4ca172817a qemu-char: add create to register_char_driver
Having creation as a member of the CharDriver struct removes the need
to export functions for qemu-char.c's usage.  After the conversion,
chardev backends implemented outside qemu-char.c will not need a stub
creation function anymore.

Ultimately all drivers will be converted.  For now, support the case
where cd->create == NULL.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-14 17:55:26 +02:00
Marc-André Lureau
f7a8beb5e6 spice: fix spice_chr_add_watch() pre-condition
Since e02bc6de30, add_watch() is called
with G_IO_HUP. Even if spice-qemu-char ignores this flag, the
precondition must be changed.

https://bugzilla.redhat.com/show_bug.cgi?id=1128992

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2015-05-29 09:56:01 +02:00
Marc-André Lureau
e95e203c08 spice-char: notify the server when chardev is writable
The spice server is polling on write, unless
SPICE_CHAR_DEVICE_NOTIFY_WRITABLE flag is set. In this case, qemu must
call spice_server_char_device_wakeup() when the frontend is writable.

Signed-off-by: Marc-André Lureau <marcandre.lureau@gmail.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2015-05-29 09:56:01 +02:00
Stefan Weil
51575c3fca spice: Add missing 'static' attribute
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-02-10 10:26:05 +03:00
Marc-André Lureau
e0883e2de0 spice: remove spice-experimental.h include
Nothing seems to be using functions from spice-experimental.h (better
that way). Let's remove its inclusion.

Signed-off-by: Marc-André Lureau <marcandre.lureau@gmail.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2014-12-16 14:15:29 +01:00
Peter Maydell
e4d50d47a9 qemu-char: Rename register_char_driver_qapi() to register_char_driver()
Now we have removed the legacy register_char_driver() we can
rename register_char_driver_qapi() to the more obvious and
shorter name.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1409653457-27863-6-git-send-email-peter.maydell@linaro.org
2014-09-16 23:36:32 +01:00
Paolo Bonzini
db39fcf1f6 qemu-char: introduce qemu_chr_alloc
The next patch will modify this function to initialize state that is
common to all backends.

Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2014-06-23 11:12:28 -04:00
Marc-André Lureau
8909114649 spice: hook qemu_chr_fe_set_open() event to ports
This wires up a spice port event on virtio-ports open/close, so the
client is notified when the other end is ready.

Signed-off-by: Marc-André Lureau <marcandre.lureau@gmail.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2014-02-03 11:05:15 +01:00
Marc-André Lureau
be733d6d48 spice-char: implement chardev port event
Wire up chardev fe_event to Spice port.

Signed-off-by: Marc-André Lureau <marcandre.lureau@gmail.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2013-12-16 10:12:20 +01:00
Marc-André Lureau
d8a03a0952 spice-char: remove unused field
Signed-off-by: Marc-André Lureau <marcandre.lureau@gmail.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2013-12-16 10:12:20 +01:00
Michael Roth
bd5c51ee6c qemu-char: don't issue CHR_EVENT_OPEN in a BH
When CHR_EVENT_OPENED was initially added, it was CHR_EVENT_RESET,
and it was issued as a bottom-half:

86e94dea5b

Which we basically used to print out a greeting/prompt for the
monitor.

AFAICT the only reason this was ever done in a BH was because in
some cases we'd modify the chr_write handler for a new chardev
backend *after* the site where we issued the reset (see:
86e94d:qemu_chr_open_stdio())

At some point this event was renamed to CHR_EVENT_OPENED, and we've
maintained the use of this BH ever since.

However, due to 9f939df955, we schedule
the BH via g_idle_add(), which is causing events to sometimes be
delivered after we've already begun processing data from backends,
leading to:

 known bugs:

  QMP:
    session negotation resets with OPENED event, in some cases this
    is causing new sessions to get sporadically reset

 potential bugs:

  hw/usb/redirect.c:
    can_read handler checks for dev->parser != NULL, which may be
    true if CLOSED BH has not been executed yet. In the past, OPENED
    quiesced outstanding CLOSED events prior to us reading client
    data. If it's delayed, our check may allow reads to occur even
    though we haven't processed the OPENED event yet, and when we
    do finally get the OPENED event, our state may get reset.

  qtest.c:
    can begin session before OPENED event is processed, leading to
    a spurious reset of the system and irq_levels

  gdbstub.c:
    may start a gdb session prior to the machine being paused

To fix these, let's just drop the BH.

Since the initial reasoning for using it still applies to an extent,
work around that by deferring the delivery of CHR_EVENT_OPENED until
after the chardevs have been fully initialized, toward the end of
qmp_chardev_add() (or some cases, qemu_chr_new_from_opts()). This
defers delivery long enough that we can be assured a CharDriverState
is fully initialized before CHR_EVENT_OPENED is sent.

Also, rather than requiring each chardev to do an explicit open, do it
automatically, and allow the small few who don't desire such behavior to
suppress the OPENED-on-init behavior by setting a 'explicit_be_open'
flag.

We additionally add missing OPENED events for stdio backends on w32,
which were previously not being issued, causing us to not recieve the
banner and initial prompts for qmp/hmp.

Reported-by: Stefan Priebe <s.priebe@profihost.ag>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Message-id: 1370636393-21044-1-git-send-email-mdroth@linux.vnet.ibm.com
Cc: qemu-stable@nongnu.org
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-06-10 11:38:37 -05:00
Hans de Goede
75c439bc65 spice-qemu-char: vmc_write: Don't write more bytes then we're asked too
This one took me eons to debug, but I've finally found it now, oh well.

The usage of the MIN macro in this line:
    last_out = MIN(len, qemu_chr_be_can_write(scd->chr));

Causes qemu_chr_be_can_write to be called *twice*, since the MIN macro
evaluates its arguments twice (bad MIN macro, bad!). And the result of
the call can change between the 2 calls since the guest may have consumed
some data from the virtio ringbuffer between the calls!

When this happens it is possible for qemu_chr_be_can_write to return less
then len in the call made for the comparision, and then to return more then
len in the actual call for the return-value of MIN, after which we will end
up writing len data + some extra garbage, not good.

This patch fixes this by only calling qemu_chr_be_can_write once.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2013-04-16 11:52:09 +02:00
Alon Levy
b010cec86b spice-qemu-char: Remove intermediate buffer
virtio-serial's buffer is valid when it calls us, and we don't
access it otherwise: vmc_read is only called in response to wakeup,
or else we set datalen=0 and throttle. Then vmc_read is called back,
we return 0 (not accessing the buffer) and set the timer to unthrottle.

Also make datalen int and not ssize_t (to fit spice_chr_write signature).

HdG: Update to apply to spice-qemu-char with new gio-channel based
flowcontrol support.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2013-04-16 11:52:09 +02:00
Hans de Goede
ae893e5e81 spice-qemu-char: Add watch support
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2013-04-16 11:52:09 +02:00
Hans de Goede
52fe0e75b7 spice-qemu-char: Remove #ifdef-ed code for old spice-server compat
We now require spice-server to be >= 0.12.0 so this is no longer needed.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2013-04-16 11:52:09 +02:00
Paolo Bonzini
dccfcd0e5f sysemu: avoid proliferation of include/ subdirectories
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-04-15 18:19:25 +02:00
Hans de Goede
e280ff5e91 spice-qemu-char: Drop hackish vmc_register on spice_chr_write
Now that the core takes care of fe_open tracking we no longer need this hack.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Message-id: 1364292483-16564-12-git-send-email-hdegoede@redhat.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-03-27 10:26:50 -05:00
Hans de Goede
574b711a92 qemu-char: Consolidate guest_close/guest_open into a set_fe_open callback
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Message-id: 1364292483-16564-7-git-send-email-hdegoede@redhat.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-03-27 10:26:49 -05:00
Hans de Goede
16665b943b qemu-char: Rename opened to be_open
Rename the opened variable to be_open to reflect that it contains the
opened state of the backend.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Message-id: 1364292483-16564-2-git-send-email-hdegoede@redhat.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-03-27 10:26:48 -05:00
Hans de Goede
344bf1e935 spice-qemu-char: Remove dead debugging code
Since commit d62e5f7036a018b2ad09f17ebd481bd28953d783
"chardev: add spice support to qapi"

It is impossible to set the debug parameter, so all the dprintf calls
are essentially nops. Since we've not needed the debug parameter in ages this
is not a problem, if it later turns out we do need some more debugging options
we can add more trace-points.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2013-03-14 09:46:18 +01:00
Hans de Goede
5e9b473a3d spice-qemu-char: Fix name parameter issues after qapi-ifying
The strings passed in through the qapi calls are dynamic memory, since
we want to have them stick around longer then just the call to
qemu_chr_open_spice_* we need to strdup them.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2013-03-14 09:46:18 +01:00
Gerd Hoffmann
cd153e2aa2 chardev: add spice support to qapi
This patch adds 'spicevmc' and 'spiceport' support to qapi and also
switches over the spice chardev initialization to the new qapi code
path.
2013-03-13 10:27:46 +01:00
Anthony Liguori
26c6061452 qemu-char: move spice registration to spice-qemu-char.c
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Message-id: 49a8d12eeb117e5530b2fab02af7681b54f9245c.1362505276.git.amit.shah@redhat.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-03-08 13:57:15 -06:00
Anthony Liguori
27dd773058 Merge remote-tracking branch 'bonzini/header-dirs' into staging
* bonzini/header-dirs: (45 commits)
  janitor: move remaining public headers to include/
  hw: move executable format header files to hw/
  fpu: move public header file to include/fpu
  softmmu: move remaining include files to include/ subdirectories
  softmmu: move include files to include/sysemu/
  misc: move include files to include/qemu/
  qom: move include files to include/qom/
  migration: move include files to include/migration/
  monitor: move include files to include/monitor/
  exec: move include files to include/exec/
  block: move include files to include/block/
  qapi: move include files to include/qobject/
  janitor: add guards to headers
  qapi: make struct Visitor opaque
  qapi: remove qapi/qapi-types-core.h
  qapi: move inclusions of qemu-common.h from headers to .c files
  ui: move files to ui/ and include/ui/
  qemu-ga: move qemu-ga files to qga/
  net: reorganize headers
  net: move net.c to net/
  ...

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2012-12-19 17:15:39 -06:00
Paolo Bonzini
927d4878b0 softmmu: move remaining include files to include/ subdirectories
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-19 08:32:46 +01:00
Paolo Bonzini
1de7afc984 misc: move include files to include/qemu/
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-19 08:32:39 +01:00
Paolo Bonzini
077805fa92 janitor: do not rely on indirect inclusions of or from qemu-char.h
Various header files rely on qemu-char.h including qemu-config.h or
main-loop.h, but they really do not need qemu-char.h at all (particularly
interesting is the case of the block layer!).  Clean this up, and also
add missing inclusions of qemu-char.h itself.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-19 08:29:52 +01:00
Marc-André Lureau
afd0b4091f spice-qemu-char: register spicevmc ports during qemu_spice_init()
Do the delayed registration of spicevmc ports after Spice server is
initialized.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2012-12-17 14:01:41 +01:00
Marc-André Lureau
7a5448ce6e spice-qemu-char: keep a list of spice chardev
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2012-12-17 14:01:41 +01:00
Marc-André Lureau
5a49d3e9a7 spice-qemu-char: add spiceport chardev
Add a new spice chardev to allow arbitrary communication between the
host and the Spice client via the spice server.

Examples:

This allows the Spice client to have a special port for the qemu
monitor:

... -chardev spiceport,name=org.qemu.monitor,id=monitorport
    -mon chardev=monitorport

v2:
- remove support for chardev to chardev linking
- conditionnaly compile with SPICE_SERVER_VERSION

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2012-12-17 14:01:41 +01:00
Marc-André Lureau
71b423f4b9 spice-qemu-char: factor out CharDriverState creation
Make the CharDriverState creation code reusable by spicevmc port.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2012-12-17 14:01:41 +01:00
Marc-André Lureau
07a54d704e spice-qemu-char: write to chardev whatever amount it can read
The current code waits until the chardev can read MIN(len, VMC_MAX)
But some chardev may never reach than amount, in fact some of them
will only ever accept write of 1. Fix the min computation and remove
the VMC_MAX constant.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2012-12-17 14:01:41 +01:00
Eduardo Elias Ferreira
4f5c017738 spice-qemu-char.c: Show what name is unsupported
Signed-off-by: Eduardo Elias Ferreira <edusf@linux.vnet.ibm.com>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2012-04-20 13:14:53 +01:00
Markus Armbruster
1f51470d04 Revert "qemu-char: Print strerror message on failure" and deps
The commit's purpose is laudable:

    The only way for chardev drivers to communicate an error was to
    return a NULL pointer, which resulted in an error message that
    said _that_ something went wrong, but not _why_.

It attempts to achieve it by changing the interface to return 0/-errno
and update qemu_chr_open_opts() to use strerror() to display a more
helpful error message.  Unfortunately, it has serious flaws:

1. Backends "socket" and "udp" return bogus error codes, because
qemu_chr_open_socket() and qemu_chr_open_udp() assume that
unix_listen_opts(), unix_connect_opts(), inet_listen_opts(),
inet_connect_opts() and inet_dgram_opts() fail with errno set
appropriately.  That assumption is wrong, and the commit turns
unspecific error messages into misleading error messages.  For
instance:

    $ qemu-system-x86_64 -nodefaults -vnc :0 -chardev socket,id=bar,host=xxx
    inet_connect: host and/or port not specified
    chardev: opening backend "socket" failed: No such file or directory

ENOENT is what happens to be in my errno when the backend returns
-errno.  Let's put ERANGE there just for giggles:

    $ qemu-system-x86_64 -nodefaults -vnc :0 -chardev socket,id=bar,host=xxx -drive if=none,iops=99999999999999999999
    inet_connect: host and/or port not specified
    chardev: opening backend "socket" failed: Numerical result out of range

Worse: when errno happens to be zero, return -errno erroneously
signals success, and qemu_chr_new_from_opts() dies dereferencing
uninitialized chr.  I observe this with "-serial unix:".

2. All qemu_chr_open_opts() knows about the error is an errno error
code.  That's simply not enough for a decent message.  For instance,
when inet_dgram() can't resolve the parameter host, which errno code
should it use?  What if it can't resolve parameter localaddr?

Clue: many backends already report errors in their open methods.
Let's revert the flawed commit along with its dependencies, and fix up
the silent error paths instead.

This reverts commit 6e1db57b2a.

Conflicts:

	console.c
	hw/baum.c
	qemu-char.c

This reverts commit aad04cd024.

The parts of commit db418a0a "Add stdio char device on windows" that
depend on the reverted change fixed up.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2012-02-24 09:06:56 -06:00
Hans de Goede
f76e4c7f16 spice-qemu-char: Generate chardev open/close events
Define a state callback and make that generate chardev open/close events when
called by the spice-server.

Notes:

1) For all but the newest spice-server versions (which have a fix for this)
the code ignores these events for a spicevmc with a subtype of vdagent, this
subtype specific knowledge is undesirable, but unavoidable for now, see:
http://lists.freedesktop.org/archives/spice-devel/2011-July/004837.html

2) This code deliberately sends the events immediately rather then from a
bh. This is done this way because:
a) There is no need to do it from a bh; and
b) Doing it from a bh actually causes issues because the spice-server may send
data immediately after the open and when the open runs from a bh, then
qemu_chr_be_can_write will return 0 for the first write which the spice-server
does not expect, when this happens the spice-server will never retry the write
causing communication to stall.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2011-11-28 16:20:51 -06:00
Peter Maydell
7b6c73690e spice-qemu-char.c: Use correct printf format char for ssize_t
Use the correct printf format string character (%z) for ssize_t.
This fixes a compile failure on 32 bit Linux with spice enabled.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2011-09-07 09:20:09 +02:00
Anthony Liguori
909cda12b5 char: rename qemu_chr_can_read() -> qemu_chr_be_can_read()
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2011-08-22 10:17:16 -05:00
Anthony Liguori
fa5efccb2a char: rename qemu_chr_read() -> qemu_chr_be_write()
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2011-08-22 10:17:16 -05:00
Anthony Liguori
7267c0947d Use glib memory allocation and free functions
qemu_malloc/qemu_free no longer exist after this commit.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2011-08-20 23:01:08 -05:00
Kevin Wolf
6e1db57b2a qemu-char: Print strerror message on failure
The only way for chardev drivers to communicate an error was to return a NULL
pointer, which resulted in an error message that said _that_ something went
wrong, but not _why_.

This patch changes the interface to return 0/-errno and updates
qemu_chr_open_opts to use strerror to display a more helpful error message.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2011-07-23 11:18:57 -05:00
Hans de Goede
35106c2df2 spice-qemu-char: Fix flow control in client -> guest direction
In the old spice-vmc device we used to have:
last_out = virtio_serial_write(&svc->port, p, MIN(len, VMC_MAX_HOST_WRITE));
if (last_out > 0)
   ...

Now in the chardev backend we have:
last_out = MIN(len, VMC_MAX_HOST_WRITE);
qemu_chr_read(scd->chr, p, last_out);
if (last_out > 0) {
   ...

Which causes us to no longer detect if the virtio port is not ready
to receive data from us. chardev actually has a mechanism to detect this,
but it requires a separate call to qemu_chr_can_read, before calling
qemu_chr_read (which return void).

This patch uses qemu_chr_can_read to fix the flow control from client to
guest.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2011-06-06 09:14:42 +02:00