| Message ID | 20190805091159.7826-5-hch@lst.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/7] dma-mapping: move the dma_get_sgtable API comments from arm to common code | expand |
On Mon, 05 Aug 2019 11:11:56 +0200, Christoph Hellwig wrote: > > Replace the local hack with the dma_can_mmap helper to check if > a given device supports mapping DMA allocations to userspace. > > Signed-off-by: Christoph Hellwig <hch@lst.de> > --- > sound/core/pcm_native.c | 5 ++--- > 1 file changed, 2 insertions(+), 3 deletions(-) > > diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c > index 703857aab00f..81c82c3ee8a2 100644 > --- a/sound/core/pcm_native.c > +++ b/sound/core/pcm_native.c > @@ -220,12 +220,11 @@ static bool hw_support_mmap(struct snd_pcm_substream *substream) > { > if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_MMAP)) > return false; > - /* architecture supports dma_mmap_coherent()? */ > -#if defined(CONFIG_ARCH_NO_COHERENT_DMA_MMAP) || !defined(CONFIG_HAS_DMA) > + if (!dma_can_mmap(substream->dma_buffer.dev.dev)) > + return false; > if (!substream->ops->mmap && > substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV) > return false; > -#endif This won't work as expected, unfortunately. It's a bit tricky check, since the driver may have its own mmap implementation via substream->ops->mmap, and the dma_buffer.dev.dev might point to another object depending on the dma_buffer.dev.type. So please replace with something like below: --- a/sound/core/pcm_native.c +++ b/sound/core/pcm_native.c @@ -221,11 +221,10 @@ static bool hw_support_mmap(struct snd_pcm_substream *substream) if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_MMAP)) return false; /* architecture supports dma_mmap_coherent()? */ -#if defined(CONFIG_ARCH_NO_COHERENT_DMA_MMAP) || !defined(CONFIG_HAS_DMA) if (!substream->ops->mmap && - substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV) + substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV && + !dma_can_mmap(substream->dma_buffer.dev.dev)) return false; -#endif return true; } Thanks! Takashi
On Mon, Aug 05, 2019 at 11:22:03AM +0200, Takashi Iwai wrote: > This won't work as expected, unfortunately. It's a bit tricky check, > since the driver may have its own mmap implementation via > substream->ops->mmap, and the dma_buffer.dev.dev might point to > another object depending on the dma_buffer.dev.type. > > So please replace with something like below: From my gut feeling I'd reorder it a bit to make it more clear like this: http://git.infradead.org/users/hch/misc.git/commitdiff/958fccf54d00c16740522f818d23f9350498e911 if this is fine it'll be in the next version, waiting for a little more feedback on the other patches.
On Tue, 06 Aug 2019 07:29:49 +0200, Christoph Hellwig wrote: > > On Mon, Aug 05, 2019 at 11:22:03AM +0200, Takashi Iwai wrote: > > This won't work as expected, unfortunately. It's a bit tricky check, > > since the driver may have its own mmap implementation via > > substream->ops->mmap, and the dma_buffer.dev.dev might point to > > another object depending on the dma_buffer.dev.type. > > > > So please replace with something like below: > > >From my gut feeling I'd reorder it a bit to make it more clear like > this: > > http://git.infradead.org/users/hch/misc.git/commitdiff/958fccf54d00c16740522f818d23f9350498e911 > > if this is fine it'll be in the next version, waiting for a little more > feedback on the other patches. Yes, the new one looks good. Reviewed-by: Takashi Iwai <tiwai@suse.de> Thanks! Takashi
diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c index 703857aab00f..81c82c3ee8a2 100644 --- a/sound/core/pcm_native.c +++ b/sound/core/pcm_native.c @@ -220,12 +220,11 @@ static bool hw_support_mmap(struct snd_pcm_substream *substream) { if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_MMAP)) return false; - /* architecture supports dma_mmap_coherent()? */ -#if defined(CONFIG_ARCH_NO_COHERENT_DMA_MMAP) || !defined(CONFIG_HAS_DMA) + if (!dma_can_mmap(substream->dma_buffer.dev.dev)) + return false; if (!substream->ops->mmap && substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV) return false; -#endif return true; }
Replace the local hack with the dma_can_mmap helper to check if a given device supports mapping DMA allocations to userspace. Signed-off-by: Christoph Hellwig <hch@lst.de> --- sound/core/pcm_native.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-)