1SND_PCM_LIB_PREALLOC(9) PCM API SND_PCM_LIB_PREALLOC(9)
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6 snd_pcm_lib_preallocate_pages - pre-allocation for the given DMA type
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9 int snd_pcm_lib_preallocate_pages(struct snd_pcm_substream * substream,
10 int type, struct device * data,
11 size_t size, size_t max);
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14 substream
15 the pcm substream instance
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17 type
18 DMA type (SNDRV_DMA_TYPE_*)
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20 data
21 DMA type dependant data
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23 size
24 the requested pre-allocation size in bytes
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26 max
27 the max. allowed pre-allocation size
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30 Do pre-allocation for the given DMA buffer type.
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32 When substream->dma_buf_id is set, the function tries to look for the
33 reserved buffer, and the buffer is not freed but reserved at
34 destruction time. The dma_buf_id must be unique for all systems (in the
35 same DMA buffer type) e.g. using snd_dma_pci_buf_id.
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37 Returns zero if successful, or a negative error code on failure.
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40Kernel Hackers Manual 2.6. November 2011 SND_PCM_LIB_PREALLOC(9)