ALSA: pcm - Call pgprot_noncached() for vmalloc'ed buffers

pgprot_noncached() can be set for vmalloc'ed buffers safely, and we'd
need non-cached behavior more or less, even for the intermediate ring-
buffers.

Now snd_pcm_lib_mmap_vmalloc() is added as the common PCM mmap callback
that is coupled with snd_pcm_lib_alloc_vmalloc_buffer() & co.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 4 insertions, 0 deletions

diff --git a/include/sound/pcm.h b/include/sound/pcm.h
index 1d4ca2aae50d..aabf48bb8ee6 100644
--- a/include/sound/pcm.h
+++ b/include/sound/pcm.h
@@ -1021,6 +1021,10 @@ int snd_pcm_lib_mmap_iomem(struct snd_pcm_substream *substream, struct vm_area_s
 #define snd_pcm_lib_mmap_iomem  NULL
 #endif
 
+int snd_pcm_lib_mmap_noncached(struct snd_pcm_substream *substream,
+                               struct vm_area_struct *area);
+#define snd_pcm_lib_mmap_vmalloc        snd_pcm_lib_mmap_noncached
+
 static inline void snd_pcm_limit_isa_dma_size(int dma, size_t *max)
 {
         *max = dma < 4 ? 64 * 1024 : 128 * 1024;