[PATCH 1/4] ALSA: pcm: Use dma_mmap_coherent() on x86, too

Takashi Iwai tiwai at suse.de
Mon Jun 15 18:00:42 CEST 2020


We avoided the explicit use of dma_mmap_coherent() on x86 because of a
spurious warning in x86 APT code in the past.  However, this blindly
assumes that the pages allocated via dma_alloc_coherent() on x86 are
the ones convertible via virt_to_page() (that is used in the default
mmap handler), and it's no longer true; with the indirect DMA ops,
this can be handled differently.  The only certain way for doing mmap
such pages is the dma_mmap_coherent(), and the warning seems already
gone in the recent code, so let's use it consistently.

Signed-off-by: Takashi Iwai <tiwai at suse.de>
---
 sound/core/pcm_native.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
index 9630d2523948..1e51c849d3d4 100644
--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -3713,7 +3713,6 @@ int snd_pcm_lib_default_mmap(struct snd_pcm_substream *substream,
 				area->vm_end - area->vm_start, area->vm_page_prot);
 	}
 #endif /* CONFIG_GENERIC_ALLOCATOR */
-#ifndef CONFIG_X86 /* for avoiding warnings arch/x86/mm/pat.c */
 	if (IS_ENABLED(CONFIG_HAS_DMA) && !substream->ops->page &&
 	    (substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV ||
 	     substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV_UC))
@@ -3722,7 +3721,6 @@ int snd_pcm_lib_default_mmap(struct snd_pcm_substream *substream,
 					 substream->runtime->dma_area,
 					 substream->runtime->dma_addr,
 					 substream->runtime->dma_bytes);
-#endif /* CONFIG_X86 */
 	/* mmap with fault handler */
 	area->vm_ops = &snd_pcm_vm_ops_data_fault;
 	return 0;
-- 
2.16.4



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