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ALSA: memalloc: Drop Xen PV workaround again

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Since recently in the commit e469e2045f ("ALSA: memalloc: Let IOMMU
handle S/G primarily"), the SG buffer allocation code was modified to
use the standard DMA code primarily and the fallback is applied only
limitedly.  This made the Xen PV specific workarounds we took in the
commit 53466ebdec ("ALSA: memalloc: Workaround for Xen PV") rather
superfluous.

It was a hackish workaround for the regression at that time, and it
seems that it's causing another issues (reportedly memory
corruptions).  So it's better to clean it up, after all.

Link: https://lore.kernel.org/20240906184209.25423-1-ariadne@ariadne.space
Cc: Ariadne Conill <ariadne@ariadne.space>
Link: https://patch.msgid.link/20240910113100.32542-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Takashi Iwai 2024-09-10 13:30:59 +02:00
parent 0ccbc99e05
commit 9408ace468
1 changed files with 3 additions and 16 deletions
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13
sound/core/memalloc.c
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@ -667,7 +667,6 @@ static const struct snd_malloc_ops snd_dma_noncontig_ops = {
#ifdef CONFIG_SND_DMA_SGBUF
/* Fallback SG-buffer allocations for x86 */
struct snd_dma_sg_fallback {
bool use_dma_alloc_coherent;
size_t count;
struct page **pages;
/* DMA address array; the first page contains #pages in ~PAGE_MASK */
@ -687,11 +686,6 @@ static void __snd_dma_sg_fallback_free(struct snd_dma_buffer *dmab,
size = sgbuf->addrs[i] & ~PAGE_MASK;
if (WARN_ON(!size))
break;
if (sgbuf->use_dma_alloc_coherent)
dma_free_coherent(dmab->dev.dev, size << PAGE_SHIFT,
page_address(sgbuf->pages[i]),
sgbuf->addrs[i] & PAGE_MASK);
else
do_free_pages(page_address(sgbuf->pages[i]),
size << PAGE_SHIFT, false);
i += size;
@ -715,7 +709,6 @@ static void *snd_dma_sg_fallback_alloc(struct snd_dma_buffer *dmab, size_t size)
sgbuf = kzalloc(sizeof(*sgbuf), GFP_KERNEL);
if (!sgbuf)
return NULL;
sgbuf->use_dma_alloc_coherent = cpu_feature_enabled(X86_FEATURE_XENPV);
size = PAGE_ALIGN(size);
sgbuf->count = size >> PAGE_SHIFT;
sgbuf->pages = kvcalloc(sgbuf->count, sizeof(*sgbuf->pages), GFP_KERNEL);
@ -728,9 +721,6 @@ static void *snd_dma_sg_fallback_alloc(struct snd_dma_buffer *dmab, size_t size)
chunk = (PAGE_SIZE - 1) << PAGE_SHIFT; /* to fit in low bits in addrs */
while (size > 0) {
chunk = min(size, chunk);
if (sgbuf->use_dma_alloc_coherent)
p = dma_alloc_coherent(dmab->dev.dev, chunk, &addr, DEFAULT_GFP);
else
p = do_alloc_pages(dmab->dev.dev, chunk, &addr, false);
if (!p) {
if (chunk <= PAGE_SIZE)
@ -803,9 +793,6 @@ static void *snd_dma_sg_alloc(struct snd_dma_buffer *dmab, size_t size)
int type = dmab->dev.type;
void *p;
if (cpu_feature_enabled(X86_FEATURE_XENPV))
return snd_dma_sg_fallback_alloc(dmab, size);
/* try the standard DMA API allocation at first */
if (type == SNDRV_DMA_TYPE_DEV_WC_SG)
dmab->dev.type = SNDRV_DMA_TYPE_DEV_WC;