From f2bb614bb6c7f5245521195f144272ef93d9f086 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Tue, 27 Jan 2015 16:17:26 +0100 Subject: [PATCH] ALSA: line6: Clear prev_fbuf and prev_fsize properly Clearing prev_fsize in line6_pcm_acquire() is pretty racy. This can be called at any time while the stream is being played. Rather better to clear prev_fbuf and prev_fsize at the proper place like the stream stop for capture, and just after copying the monitor / impulse data inside the spinlock. Tested-by: Chris Rorvick Signed-off-by: Takashi Iwai --- sound/usb/line6/pcm.c | 8 ++++---- sound/usb/line6/playback.c | 6 +++--- 2 files changed, 7 insertions(+), 7 deletions(-) diff --git a/sound/usb/line6/pcm.c b/sound/usb/line6/pcm.c index f75825995e24..dedbe24cbf60 100644 --- a/sound/usb/line6/pcm.c +++ b/sound/usb/line6/pcm.c @@ -171,8 +171,6 @@ int line6_pcm_acquire(struct snd_line6_pcm *line6pcm, int channels) flags_final = 0; - line6pcm->prev_fbuf = NULL; - if (test_flags(flags_old, flags_new, LINE6_BITS_CAPTURE_BUFFER)) { err = line6_alloc_stream_buffer(line6pcm, &line6pcm->in); if (err < 0) @@ -193,7 +191,6 @@ int line6_pcm_acquire(struct snd_line6_pcm *line6pcm, int channels) } line6pcm->in.count = 0; - line6pcm->prev_fsize = 0; err = line6_submit_audio_in_all_urbs(line6pcm); if (err < 0) @@ -248,8 +245,11 @@ int line6_pcm_release(struct snd_line6_pcm *line6pcm, int channels) flags_new = flags_old & ~channels; } while (cmpxchg(&line6pcm->flags, flags_old, flags_new) != flags_old); - if (test_flags(flags_new, flags_old, LINE6_BITS_CAPTURE_STREAM)) + if (test_flags(flags_new, flags_old, LINE6_BITS_CAPTURE_STREAM)) { line6_unlink_audio_urbs(line6pcm, &line6pcm->in); + line6pcm->prev_fbuf = NULL; + line6pcm->prev_fsize = 0; + } if (test_flags(flags_new, flags_old, LINE6_BITS_CAPTURE_BUFFER)) { line6_wait_clear_audio_urbs(line6pcm, &line6pcm->in); diff --git a/sound/usb/line6/playback.c b/sound/usb/line6/playback.c index b4a26d0c8267..242265929145 100644 --- a/sound/usb/line6/playback.c +++ b/sound/usb/line6/playback.c @@ -166,9 +166,7 @@ static int submit_audio_out_urb(struct snd_line6_pcm *line6pcm) struct usb_iso_packet_descriptor *fout = &urb_out->iso_frame_desc[i]; - if (line6pcm->flags & LINE6_BITS_CAPTURE_STREAM) - fsize = line6pcm->prev_fsize; - + fsize = line6pcm->prev_fsize; if (fsize == 0) { int n; @@ -263,6 +261,8 @@ static int submit_audio_out_urb(struct snd_line6_pcm *line6pcm) line6pcm->volume_monitor, bytes_per_frame); } + line6pcm->prev_fbuf = NULL; + line6pcm->prev_fsize = 0; } spin_unlock(&line6pcm->in.lock);