From 30b7ba6972d59cdf3ffce161ab9005a5f7562f9f Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Wed, 9 Jun 2021 18:25:51 +0200 Subject: [PATCH] ALSA: core: Add continuous and vmalloc mmap ops The mmap of continuous pages and vmalloc'ed pages are relatively easily done in a shot with the existing helper functions. Implement the mmap ops for those types, so that the mmap works without relying on the page fault handling. Link: https://lore.kernel.org/r/20210609162551.7842-6-tiwai@suse.de Signed-off-by: Takashi Iwai --- sound/core/memalloc.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/sound/core/memalloc.c b/sound/core/memalloc.c index bdcb9230acf8..83b79edfa52d 100644 --- a/sound/core/memalloc.c +++ b/sound/core/memalloc.c @@ -211,9 +211,19 @@ static void snd_dma_continuous_free(struct snd_dma_buffer *dmab) free_pages_exact(dmab->area, dmab->bytes); } +static int snd_dma_continuous_mmap(struct snd_dma_buffer *dmab, + struct vm_area_struct *area) +{ + return remap_pfn_range(area, area->vm_start, + dmab->addr >> PAGE_SHIFT, + area->vm_end - area->vm_start, + area->vm_page_prot); +} + static const struct snd_malloc_ops snd_dma_continuous_ops = { .alloc = snd_dma_continuous_alloc, .free = snd_dma_continuous_free, + .mmap = snd_dma_continuous_mmap, }; /* @@ -232,6 +242,12 @@ static void snd_dma_vmalloc_free(struct snd_dma_buffer *dmab) vfree(dmab->area); } +static int snd_dma_vmalloc_mmap(struct snd_dma_buffer *dmab, + struct vm_area_struct *area) +{ + return remap_vmalloc_range(area, dmab->area, 0); +} + static dma_addr_t snd_dma_vmalloc_get_addr(struct snd_dma_buffer *dmab, size_t offset) { @@ -259,6 +275,7 @@ snd_dma_vmalloc_get_chunk_size(struct snd_dma_buffer *dmab, static const struct snd_malloc_ops snd_dma_vmalloc_ops = { .alloc = snd_dma_vmalloc_alloc, .free = snd_dma_vmalloc_free, + .mmap = snd_dma_vmalloc_mmap, .get_addr = snd_dma_vmalloc_get_addr, .get_page = snd_dma_vmalloc_get_page, .get_chunk_size = snd_dma_vmalloc_get_chunk_size,