Mercurial > sdl-ios-xcode
view src/audio/mint/SDL_mintaudio_it.S @ 1176:dd2a8deeb26d
Date: Mon, 17 Oct 2005 20:09:03 -0400
From: Mark Schreiber <mark7@alumni.cmu.edu>
To: ryan@clutteredmind.org
Subject: [PATCH]SDL mprotect() crash fix
(I'm going to throw this patch your way at the suggestion of #SDL --
for some reason, I had some difficulty sending it to the main list
last time, and I go bonkers subscribing to send each email or
patch...)
Currently, when I run SDL applications as non-root using
SDL_VIDEODRIVER=dga, the fbdev fallback mprotect()s read/write the
proper size of mmapped /dev/fb0 (7.5MB), but on framebuffer release
mprotect()s read-only the range by the entire size of my video memory
(128MB), which causes a segfault:
#0 0x002a9a27 in ?? () from /lib/libc.so.6
#1 0x04a63eb6 in SDL_XDGAUnmapFramebuffer (screen=3D0) at XF86DGA2.c:978
#2 0x04a63efc in SDL_XDGACloseFramebuffer (dpy=3D0x9d3f008, screen=3D0)
at XF86DGA2.c:268
#3 0x04a68b57 in DGA_Available () at SDL_dgavideo.c:98
#4 0x04a53677 in SDL_VideoInit (driver_name=3D0xbfb0bfc7 "dga", flags=3D0)
at SDL_video.c:180
#5 0x04a2613f in SDL_InitSubSystem (flags=3D32) at SDL.c:74
#6 0x04a2617c in SDL_Init (flags=3D32) at SDL.c:166
#7 0x08049722 in main (argc=3D1, argv=3D0x0) at testwin.c:32
This is SDL 1.2.8 on Fedora Core 4, radeon driver for a Radeon 9250,
xorg-x11-6.8.2-37.
I've attached a one-line patch against SDL CVS that updates the size
of the framebuffer at framebuffer map time so that the mprotect() on
unmap will be the same size. I'm not sure if this is the best
approach (i.e. one might want to retain the original value), but it
does make my SDL applications work without segfaulting.
-- Best of luck, Mark Schreiber
| author | Ryan C. Gordon <icculus@icculus.org> |
|---|---|
| date | Sat, 19 Nov 2005 18:57:00 +0000 |
| parents | c83fa1c650dd |
| children | d48ead2d2ba5 ea2a327b92d7 |
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/* SDL - Simple DirectMedia Layer Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002 Sam Lantinga This library is free software; you can redistribute it and/or modify it under the terms of the GNU Library General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public License for more details. You should have received a copy of the GNU Library General Public License along with this library; if not, write to the Free Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA Sam Lantinga slouken@libsdl.org */ /* Audio interrupts Patrice Mandin, Didier Méquignon */ .text .globl _SDL_MintAudio_Callback .globl _SDL_MintAudio_XbiosInterrupt .globl _SDL_MintAudio_XbiosInterruptMeasureClock .globl _SDL_MintAudio_Dma8Interrupt .globl _SDL_MintAudio_StfaInterrupt .globl _SDL_MintAudio_mutex .globl _SDL_MintAudio_audiobuf .globl _SDL_MintAudio_numbuf .globl _SDL_MintAudio_audiosize .globl _SDL_MintAudio_clocktics .globl _SDL_MintAudio_stfa /* How it works: - Audio is playing buffer #0 (resp. #1) - We must calculate a sample in buffer #1 (resp. #0) so we first call the callback to do it - Then we swap the buffers */ #define savptr 0x4a2 #define savamt 0x46 /*--- Xbios interrupt vector to measure Falcon external clock ---*/ _SDL_MintAudio_XbiosInterruptMeasureClock: /* 1 mS */ btst #0,0xFFFF8901:w /* state DMA sound */ beqs SDL_MintAudio_EndIntMeasure addql #1,_SDL_MintAudio_clocktics SDL_MintAudio_EndIntMeasure: bclr #5,0xFFFFFA0F:w /* Clear service bit */ rte /*--- Xbios interrupt vector ---*/ _SDL_MintAudio_XbiosInterrupt: /* Reenable interrupts, so other interrupts can work */ movew #0x2300,sr /* Clear service bit, so other MFP interrupts can work */ bclr #5,0xfffffa0f:w /* Check if we are not already running */ tstw _SDL_MintAudio_mutex bnes SDL_MintAudio_XbiosEnd notw _SDL_MintAudio_mutex /* Swap buffers */ eorw #1,_SDL_MintAudio_numbuf moveml d0-d7/a0-a6,sp@- /* Callback */ jsr _SDL_MintAudio_Callback /* Reserve space for registers */ subl #savamt,savptr /* Set new buffer */ moveq #0,d0 movel _SDL_MintAudio_audiosize,d1 movew _SDL_MintAudio_numbuf,d0 lsll #2,d0 lea _SDL_MintAudio_audiobuf,a0 movel a0@(d0:l),a1 lea a1@(d1:l),a2 movel a2,sp@- movel a1,sp@- clrw sp@- movew #131,sp@- trap #14 lea sp@(12),sp /* Restore registers space */ addl #savamt,savptr moveml sp@+,d0-d7/a0-a6 clrw _SDL_MintAudio_mutex SDL_MintAudio_XbiosEnd: rte /*--- DMA 8 bits interrupt vector ---*/ _SDL_MintAudio_Dma8Interrupt: /* Reenable interrupts, so other interrupts can work */ movew #0x2300,sr /* Clear service bit, so other MFP interrupts can work */ bclr #5,0xfffffa0f:w /* Check if we are not already running */ tstw _SDL_MintAudio_mutex bnes SDL_MintAudio_Dma8End notw _SDL_MintAudio_mutex /* Swap buffers */ eorw #1,_SDL_MintAudio_numbuf moveml d0-d7/a0-a6,sp@- /* Callback */ jsr _SDL_MintAudio_Callback /* Set new buffer */ moveq #0,d0 movew _SDL_MintAudio_numbuf,d0 lslw #2,d0 lea _SDL_MintAudio_audiobuf,a0 movel a0@(d0:w),d1 /* Modify DMA addresses */ lea 0xffff8900:w,a0 moveb d1,a0@(0x07) /* Start address */ rorl #8,d1 moveb d1,a0@(0x05) rorl #8,d1 moveb d1,a0@(0x03) swap d1 addl _SDL_MintAudio_audiosize,d1 moveb d1,a0@(0x13) /* End address */ rorl #8,d1 moveb d1,a0@(0x11) rorl #8,d1 moveb d1,a0@(0x0f) moveml sp@+,d0-d7/a0-a6 clrw _SDL_MintAudio_mutex SDL_MintAudio_Dma8End: rte /*--- STFA interrupt vector ---*/ STFA_SOUND_START = 6 STFA_SOUND_END = STFA_SOUND_START+8 _SDL_MintAudio_StfaInterrupt: /* Reenable interrupts, so other interrupts can work */ movew #0x2300,sr /* Check if we are not already running */ tstw _SDL_MintAudio_mutex bnes SDL_MintAudio_StfaEnd notw _SDL_MintAudio_mutex /* Swap buffers */ eorw #1,_SDL_MintAudio_numbuf moveml d0-d7/a0-a6,sp@- /* Callback */ jsr _SDL_MintAudio_Callback /* Set new buffer */ moveq #0,d0 movel _SDL_MintAudio_stfa,a1 movew _SDL_MintAudio_numbuf,d0 lslw #2,d0 lea _SDL_MintAudio_audiobuf,a0 movel a0@(d0:w),d1 /* Modify STFA replay buffers */ movel d1,a1@(STFA_SOUND_START) addl _SDL_MintAudio_audiosize,d1 movel d1,a1@(STFA_SOUND_END) moveml sp@+,d0-d7/a0-a6 clrw _SDL_MintAudio_mutex SDL_MintAudio_StfaEnd: rte