ALSA: pcm: Fix mmap capability check

The hw_support_mmap() doesn't cover all memory allocation types and
might use a wrong device pointer for checking the capability.
Check the all memory allocation types more completely.

Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20210720092640.12338-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
index c88c431..6919d29 100644 (file)
--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -246,12 +246,18 @@ static bool hw_support_mmap(struct snd_pcm_substream *substream)
        if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_MMAP))
                return false;
 
-       if (substream->ops->mmap ||
-           (substream->dma_buffer.dev.type != SNDRV_DMA_TYPE_DEV &&
-            substream->dma_buffer.dev.type != SNDRV_DMA_TYPE_DEV_UC))
+       if (substream->ops->mmap)
                return true;
 
-       return dma_can_mmap(substream->dma_buffer.dev.dev);
+       switch (substream->dma_buffer.dev.type) {
+       case SNDRV_DMA_TYPE_UNKNOWN:
+               return false;
+       case SNDRV_DMA_TYPE_CONTINUOUS:
+       case SNDRV_DMA_TYPE_VMALLOC:
+               return true;
+       default:
+               return dma_can_mmap(substream->dma_buffer.dev.dev);
+       }
 }
 
 static int constrain_mask_params(struct snd_pcm_substream *substream,