| Message ID | 20210720092640.12338-1-tiwai@suse.de |
|---|---|
| State | Accepted |
| Commit | c4824ae7db418aee6f50f308a20b832e58e997fd |
| Headers | show |
| Series | ALSA: pcm: Fix mmap capability check | expand |
On Fri, 30 Jul 2021 09:19:16 +0200, Jaroslav Kysela wrote: > > On 20. 07. 21 11:26, Takashi Iwai wrote: > > 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. > > This change breaks mmap for the snd-dummy driver (fake_buffer). It seems that > we need this fix? > > diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c > index 6a2971a7e6a1..09c0e2a6489c 100644 > --- a/sound/core/pcm_native.c > +++ b/sound/core/pcm_native.c > @@ -246,7 +246,7 @@ 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) > + if (substream->ops->mmap || substream->ops->page) > return true; > > switch (substream->dma_buffer.dev.type) { Yes, that would work. Or allowing the mmap for unknown buffer type by blindly relying to the hw.info flag. But ops->page check looks safer. Care to submit a proper patch? Thanks! Takashi
diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c index c88c4316c417..6919d2943b9d 100644 --- 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,
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> Signed-off-by: Takashi Iwai <tiwai@suse.de> --- sound/core/pcm_native.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-)