qdsp5: audio: Protect common data between ADSP ISR and flush operation
During NEEDS_DATA or BUFFER_UPDATE event processing in ISR
context, if flush command is issued by application then
there is chance of concurrent access of some of the variables
shared between ISR and Process context. This may result in race
condition causing values of these shared variables to be
inconsistent.
Fix this by protecting these variables using spin lock. Also corrected
locking sequence order in encode drivers.
Change-Id: I06b4d08053ad13d1b118ab6f29e69e95b49d133f
Signed-off-by: Manish Dewangan <manish@codeaurora.org>
diff --git a/arch/arm/mach-msm/qdsp5/audio_mp3.c b/arch/arm/mach-msm/qdsp5/audio_mp3.c
index c4b464a..dfd8528 100644
--- a/arch/arm/mach-msm/qdsp5/audio_mp3.c
+++ b/arch/arm/mach-msm/qdsp5/audio_mp3.c
@@ -4,7 +4,7 @@
*
* Copyright (C) 2008 Google, Inc.
* Copyright (C) 2008 HTC Corporation
- * Copyright (c) 2009-2011, Code Aurora Forum. All rights reserved.
+ * Copyright (c) 2009-2012, Code Aurora Forum. All rights reserved.
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
@@ -853,12 +853,16 @@
static void audio_flush(struct audio *audio)
{
+ unsigned long flags;
+
+ spin_lock_irqsave(&audio->dsp_lock, flags);
audio->out[0].used = 0;
audio->out[1].used = 0;
audio->out_head = 0;
audio->out_tail = 0;
audio->reserved = 0;
audio->out_needed = 0;
+ spin_unlock_irqrestore(&audio->dsp_lock, flags);
atomic_set(&audio->out_bytes, 0);
}
@@ -885,13 +889,15 @@
static void audio_flush_pcm_buf(struct audio *audio)
{
uint8_t index;
+ unsigned long flags;
+ spin_lock_irqsave(&audio->dsp_lock, flags);
for (index = 0; index < PCM_BUF_MAX_COUNT; index++)
audio->in[index].used = 0;
-
audio->buf_refresh = 0;
audio->read_next = 0;
audio->fill_next = 0;
+ spin_unlock_irqrestore(&audio->dsp_lock, flags);
}
static void audio_ioport_reset(struct audio *audio)