This is a note to let you know that I've just added the patch titled
ALSA: pcm: Check mmap capability of runtime dma buffer at first
to the 5.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
alsa-pcm-check-mmap-capability-of-runtime-dma-buffer-at-first.patch
and it can be found in the queue-5.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From cbea6e5a7772b7a5b80baa8f98fd77853487fd2a Mon Sep 17 00:00:00 2001
From: Takashi Iwai <tiwai@xxxxxxx>
Date: Mon, 9 Aug 2021 09:18:27 +0200
Subject: ALSA: pcm: Check mmap capability of runtime dma buffer at first
From: Takashi Iwai <tiwai@xxxxxxx>
commit cbea6e5a7772b7a5b80baa8f98fd77853487fd2a upstream.
Currently we check only the substream->dma_buffer as the preset of the
buffer configuration for verifying the availability of mmap. But a
few drivers rather set up the buffer in the own way without the
standard buffer preallocation using substream->dma_buffer, and they
miss the proper checks. (Now it's working more or less fine as most
of them are running only on x86).
Actually, they may set up the runtime dma_buffer (referred via
snd_pcm_get_dma_buf()) at the open callback, though. That is, this
could have been used as the primary source.
This patch changes the hw_support_mmap() function to check the runtime
dma buffer at first. It's usually NULL with the standard buffer
preallocation, and in that case, we continue checking
substream->dma_buffer as fallback.
Link: https://lore.kernel.org/r/20210809071829.22238-2-tiwai@xxxxxxx
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
sound/core/pcm_native.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -243,13 +243,18 @@ int snd_pcm_info_user(struct snd_pcm_sub
static bool hw_support_mmap(struct snd_pcm_substream *substream)
{
+ struct snd_dma_buffer *dmabuf;
+
if (!(substream->runtime->hw.info & SNDRV_PCM_INFO_MMAP))
return false;
if (substream->ops->mmap || substream->ops->page)
return true;
- switch (substream->dma_buffer.dev.type) {
+ dmabuf = snd_pcm_get_dma_buf(substream);
+ if (!dmabuf)
+ dmabuf = &substream->dma_buffer;
+ switch (dmabuf->dev.type) {
case SNDRV_DMA_TYPE_UNKNOWN:
/* we can't know the device, so just assume that the driver does
* everything right
@@ -259,7 +264,7 @@ static bool hw_support_mmap(struct snd_p
case SNDRV_DMA_TYPE_VMALLOC:
return true;
default:
- return dma_can_mmap(substream->dma_buffer.dev.dev);
+ return dma_can_mmap(dmabuf->dev.dev);
}
}
Patches currently in stable-queue which might be from tiwai@xxxxxxx are
queue-5.14/alsa-pci-rme-set-up-buffer-type-properly.patch
queue-5.14/alsa-pcm-check-mmap-capability-of-runtime-dma-buffer-at-first.patch
queue-5.14/alsa-pci-cs46xx-fix-set-up-buffer-type-properly.patch
