 175b2a6e4b
			
		
	
	
		175b2a6e4b
		
	
	
	
	
		
			
			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>
		
			
				
	
	
		
			89 lines
		
	
	
		
			2.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			89 lines
		
	
	
		
			2.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * QEMU VNC display driver
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|  *
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|  * From libvncserver/rfb/rfbproto.h
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|  * Copyright (C) 2005 Rohit Kumar, Johannes E. Schindelin
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|  * Copyright (C) 2000-2002 Constantin Kaplinsky.  All Rights Reserved.
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|  * Copyright (C) 2000 Tridia Corporation.  All Rights Reserved.
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|  * Copyright (C) 1999 AT&T Laboratories Cambridge.  All Rights Reserved.
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|  *
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|  *
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|  * Permission is hereby granted, free of charge, to any person obtaining a copy
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|  * of this software and associated documentation files (the "Software"), to deal
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|  * in the Software without restriction, including without limitation the rights
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|  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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|  * copies of the Software, and to permit persons to whom the Software is
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|  * furnished to do so, subject to the following conditions:
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|  *
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|  * The above copyright notice and this permission notice shall be included in
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|  * all copies or substantial portions of the Software.
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|  *
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|  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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|  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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|  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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|  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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|  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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|  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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|  * THE SOFTWARE.
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|  */
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| 
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| #ifndef VNC_JOBS_H
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| #define VNC_JOBS_H
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| 
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| /* Jobs */
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| VncJob *vnc_job_new(VncState *vs);
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| int vnc_job_add_rect(VncJob *job, int x, int y, int w, int h);
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| void vnc_job_push(VncJob *job);
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| bool vnc_has_job(VncState *vs);
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| void vnc_jobs_clear(VncState *vs);
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| void vnc_jobs_join(VncState *vs);
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| 
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| #ifdef CONFIG_VNC_THREAD
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| 
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| void vnc_jobs_consume_buffer(VncState *vs);
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| void vnc_start_worker_thread(void);
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| bool vnc_worker_thread_running(void);
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| void vnc_stop_worker_thread(void);
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| 
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| #endif /* CONFIG_VNC_THREAD */
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| 
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| /* Locks */
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| static inline int vnc_trylock_display(VncDisplay *vd)
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| {
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| #ifdef CONFIG_VNC_THREAD
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|     return qemu_mutex_trylock(&vd->mutex);
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| #else
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|     return 0;
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| #endif
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| }
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| 
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| static inline void vnc_lock_display(VncDisplay *vd)
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| {
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| #ifdef CONFIG_VNC_THREAD
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|     qemu_mutex_lock(&vd->mutex);
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| #endif
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| }
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| 
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| static inline void vnc_unlock_display(VncDisplay *vd)
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| {
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| #ifdef CONFIG_VNC_THREAD
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|     qemu_mutex_unlock(&vd->mutex);
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| #endif
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| }
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| 
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| static inline void vnc_lock_output(VncState *vs)
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| {
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| #ifdef CONFIG_VNC_THREAD
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|     qemu_mutex_lock(&vs->output_mutex);
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| #endif
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| }
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| 
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| static inline void vnc_unlock_output(VncState *vs)
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| {
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| #ifdef CONFIG_VNC_THREAD
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|     qemu_mutex_unlock(&vs->output_mutex);
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| #endif
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| }
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| 
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| #endif /* VNC_JOBS_H */
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