table of contents
| SND_PCM_LIB_PREALLOC(9) | PCM API | SND_PCM_LIB_PREALLOC(9) |
NAME¶
snd_pcm_lib_preallocate_pages - pre-allocation for the given DMA type
SYNOPSIS¶
int snd_pcm_lib_preallocate_pages(struct snd_pcm_substream * substream, int type, struct device * data, size_t size, size_t max);
ARGUMENTS¶
substream
the pcm substream instance
type
DMA type (SNDRV_DMA_TYPE_*)
data
DMA type dependant data
size
the requested pre-allocation size in bytes
max
the max. allowed pre-allocation size
DESCRIPTION¶
Do pre-allocation for the given DMA buffer type.
When substream->dma_buf_id is set, the function tries to look for the reserved buffer, and the buffer is not freed but reserved at destruction time. The dma_buf_id must be unique for all systems (in the same DMA buffer type) e.g. using snd_dma_pci_buf_id.
Returns zero if successful, or a negative error code on failure.
COPYRIGHT¶
| May 2024 | Kernel Hackers Manual 2.6. |