参照元†
- struct snd_pcm_substream *substream
- size_t size
返り値†
/*
* try to allocate as the large pages as possible.
* stores the resultant memory size in *res_size.
*
* the minimum size is snd_minimum_buffer. it should be power of 2.
*/
static int preallocate_pcm_pages(struct snd_pcm_substream *substream, size_t size)
{
struct snd_dma_buffer *dmab = &substream->dma_buffer;
size_t orig_size = size;
int err;
do {
if ((err = snd_dma_alloc_pages(dmab->dev.type, dmab->dev.dev,
size, dmab)) < 0) {
if (err != -ENOMEM)
return err; /* fatal error */
} else
return 0;
- dmab->dev は struct snd_dma_device 型
size >>= 1;
} while (size >= snd_minimum_buffer);
dmab->bytes = 0; /* tell error */
pr_warn("ALSA pcmC%dD%d%c,%d:%s: cannot preallocate for size %zu\n",
substream->pcm->card->number, substream->pcm->device,
substream->stream ? 'c' : 'p', substream->number,
substream->pcm->name, orig_size);
- substream->pcm は struct snd_pcm * 型
- substream->pcm->card は struct snd_card * 型
- substream->pcm->device は int 型
return 0;
}
コメント†