* [PATCH] ALSA: pcm: Fix mmap capability check
@ 2021-07-20 9:26 Takashi Iwai
2021-07-30 7:19 ` Jaroslav Kysela
0 siblings, 1 reply; 3+ messages in thread
From: Takashi Iwai @ 2021-07-20 9:26 UTC (permalink / raw)
To: alsa-devel
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(-)
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,
--
2.26.2
^ permalink raw reply related [flat|nested] 3+ messages in thread* Re: [PATCH] ALSA: pcm: Fix mmap capability check
2021-07-20 9:26 [PATCH] ALSA: pcm: Fix mmap capability check Takashi Iwai
@ 2021-07-30 7:19 ` Jaroslav Kysela
2021-07-30 7:42 ` Takashi Iwai
0 siblings, 1 reply; 3+ messages in thread
From: Jaroslav Kysela @ 2021-07-30 7:19 UTC (permalink / raw)
To: Takashi Iwai, alsa-devel
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) {
Jaroslav
>
> 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(-)
>
> 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,
>
--
Jaroslav Kysela <perex@perex.cz>
Linux Sound Maintainer; ALSA Project; Red Hat, Inc.
^ permalink raw reply related [flat|nested] 3+ messages in thread* Re: [PATCH] ALSA: pcm: Fix mmap capability check
2021-07-30 7:19 ` Jaroslav Kysela
@ 2021-07-30 7:42 ` Takashi Iwai
0 siblings, 0 replies; 3+ messages in thread
From: Takashi Iwai @ 2021-07-30 7:42 UTC (permalink / raw)
To: Jaroslav Kysela; +Cc: alsa-devel
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
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2021-07-30 7:43 UTC | newest]
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2021-07-20 9:26 [PATCH] ALSA: pcm: Fix mmap capability check Takashi Iwai
2021-07-30 7:19 ` Jaroslav Kysela
2021-07-30 7:42 ` Takashi Iwai
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