From 1714332719fc91507ca24dd3567e50d7094b3001 Mon Sep 17 00:00:00 2001 From: Rob Duncan Date: Mon, 16 Jul 2018 16:35:23 -0700 Subject: [PATCH] pcm: ioplug: Transfer all available data The snd_pcm_mmap_begin() call returns the amount of contiguous data, which is less than the total available if it wraps around the buffer boundary. If we don't handle this split we leave stale data in the buffer that should have been overwritten, as well as unread data in the io_plugin that gets transferred on a subsequent call at the wrong offset. Signed-off-by: Rob Duncan Signed-off-by: Takashi Iwai --- src/pcm/pcm_ioplug.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/src/pcm/pcm_ioplug.c b/src/pcm/pcm_ioplug.c index 6d52c27b..881a1a85 100644 --- a/src/pcm/pcm_ioplug.c +++ b/src/pcm/pcm_ioplug.c @@ -716,6 +716,8 @@ static snd_pcm_sframes_t snd_pcm_ioplug_avail_update(snd_pcm_t *pcm) snd_pcm_ioplug_hw_ptr_update(pcm); if (io->data->state == SND_PCM_STATE_XRUN) return -EPIPE; + + avail = snd_pcm_mmap_avail(pcm); if (pcm->stream == SND_PCM_STREAM_CAPTURE && pcm->access != SND_PCM_ACCESS_RW_INTERLEAVED && pcm->access != SND_PCM_ACCESS_RW_NONINTERLEAVED) { @@ -728,9 +730,19 @@ static snd_pcm_sframes_t snd_pcm_ioplug_avail_update(snd_pcm_t *pcm) result = io->data->callback->transfer(io->data, areas, offset, size); if (result < 0) return result; + + /* If the available data doesn't fit in the + contiguous area at the end of the mmap we + must transfer the remaining data to the + beginning of the mmap. */ + if (size < avail) { + result = io->data->callback->transfer(io->data, areas, + 0, avail - size); + if (result < 0) + return result; + } } } - avail = snd_pcm_mmap_avail(pcm); if (avail > io->avail_max) io->avail_max = avail; return (snd_pcm_sframes_t)avail; -- 2.47.3