qemu-patch-raspberry4/ui/vnc-jobs.h
Corentin Chary 175b2a6e4b vnc: don't mess up with iohandlers in the vnc thread
The threaded VNC servers messed up with QEMU fd handlers without
any kind of locking, and that can cause some nasty race conditions.

Using qemu_mutex_lock_iothread() won't work because vnc_dpy_cpy(),
which will wait for the current job queue to finish, can be called with
the iothread lock held.

Instead, we now store the data in a temporary buffer, and use a bottom
half to notify the main thread that new data is available.

vnc_[un]lock_ouput() is still needed to access VncState members like
abort, csock or jobs_buffer.

Signed-off-by: Corentin Chary <corentin.chary@gmail.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2012-03-14 16:22:46 -05:00

89 lines
2.5 KiB
C

/*
* QEMU VNC display driver
*
* From libvncserver/rfb/rfbproto.h
* Copyright (C) 2005 Rohit Kumar, Johannes E. Schindelin
* Copyright (C) 2000-2002 Constantin Kaplinsky. All Rights Reserved.
* Copyright (C) 2000 Tridia Corporation. All Rights Reserved.
* Copyright (C) 1999 AT&T Laboratories Cambridge. All Rights Reserved.
*
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#ifndef VNC_JOBS_H
#define VNC_JOBS_H
/* Jobs */
VncJob *vnc_job_new(VncState *vs);
int vnc_job_add_rect(VncJob *job, int x, int y, int w, int h);
void vnc_job_push(VncJob *job);
bool vnc_has_job(VncState *vs);
void vnc_jobs_clear(VncState *vs);
void vnc_jobs_join(VncState *vs);
#ifdef CONFIG_VNC_THREAD
void vnc_jobs_consume_buffer(VncState *vs);
void vnc_start_worker_thread(void);
bool vnc_worker_thread_running(void);
void vnc_stop_worker_thread(void);
#endif /* CONFIG_VNC_THREAD */
/* Locks */
static inline int vnc_trylock_display(VncDisplay *vd)
{
#ifdef CONFIG_VNC_THREAD
return qemu_mutex_trylock(&vd->mutex);
#else
return 0;
#endif
}
static inline void vnc_lock_display(VncDisplay *vd)
{
#ifdef CONFIG_VNC_THREAD
qemu_mutex_lock(&vd->mutex);
#endif
}
static inline void vnc_unlock_display(VncDisplay *vd)
{
#ifdef CONFIG_VNC_THREAD
qemu_mutex_unlock(&vd->mutex);
#endif
}
static inline void vnc_lock_output(VncState *vs)
{
#ifdef CONFIG_VNC_THREAD
qemu_mutex_lock(&vs->output_mutex);
#endif
}
static inline void vnc_unlock_output(VncState *vs)
{
#ifdef CONFIG_VNC_THREAD
qemu_mutex_unlock(&vs->output_mutex);
#endif
}
#endif /* VNC_JOBS_H */