Commit a202bd1a authored by Takashi Iwai's avatar Takashi Iwai
Browse files

ALSA: core: Move mmap handler into memalloc ops 

This patch moves the mmap handling code into the common memalloc
handler.  It allows us to reduce the memory-type specific code in PCM
code gracefully.

Link: https://lore.kernel.org/r/20210609162551.7842-5-tiwai@suse.de


Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
parent 37af81c5

include/sound/memalloc.h

+3 −0
Original line number Diff line number Diff line
@@ -11,6 +11,7 @@ 


struct device;

struct page;

struct vm_area_struct;



/*

 * buffer device info
@@ -69,6 +70,8 @@ int snd_dma_alloc_pages(int type, struct device *dev, size_t size, 
int snd_dma_alloc_pages_fallback(int type, struct device *dev, size_t size,

                                 struct snd_dma_buffer *dmab);

void snd_dma_free_pages(struct snd_dma_buffer *dmab);

int snd_dma_buffer_mmap(struct snd_dma_buffer *dmab,

			struct vm_area_struct *area);



dma_addr_t snd_sgbuf_get_addr(struct snd_dma_buffer *dmab, size_t offset);

struct page *snd_sgbuf_get_page(struct snd_dma_buffer *dmab, size_t offset);

sound/core/memalloc.c

+36 −0
Original line number Diff line number Diff line
@@ -127,6 +127,23 @@ void snd_dma_free_pages(struct snd_dma_buffer *dmab) 
}

EXPORT_SYMBOL(snd_dma_free_pages);



/**

 * snd_dma_buffer_mmap - perform mmap of the given DMA buffer

 * @dmab: buffer allocation information

 * @area: VM area information

 */

int snd_dma_buffer_mmap(struct snd_dma_buffer *dmab,

			struct vm_area_struct *area)

{

	const struct snd_malloc_ops *ops = snd_dma_get_ops(dmab);



	if (ops && ops->mmap)

		return ops->mmap(dmab, area);

	else

		return -ENOENT;

}

EXPORT_SYMBOL(snd_dma_buffer_mmap);



/**

 * snd_sgbuf_get_addr - return the physical address at the corresponding offset

 * @dmab: buffer allocation information
@@ -283,9 +300,20 @@ static void snd_dma_iram_free(struct snd_dma_buffer *dmab) 
		gen_pool_free(pool, (unsigned long)dmab->area, dmab->bytes);

}



static int snd_dma_iram_mmap(struct snd_dma_buffer *dmab,

			     struct vm_area_struct *area)

{

	area->vm_page_prot = pgprot_writecombine(area->vm_page_prot);

	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_iram_ops = {

	.alloc = snd_dma_iram_alloc,

	.free = snd_dma_iram_free,

	.mmap = snd_dma_iram_mmap,

};

#endif /* CONFIG_GENERIC_ALLOCATOR */
@@ -320,9 +348,17 @@ static void snd_dma_dev_free(struct snd_dma_buffer *dmab) 
	dma_free_coherent(dmab->dev.dev, dmab->bytes, dmab->area, dmab->addr);

}



static int snd_dma_dev_mmap(struct snd_dma_buffer *dmab,

			    struct vm_area_struct *area)

{

	return dma_mmap_coherent(dmab->dev.dev, area,

				 dmab->area, dmab->addr, dmab->bytes);

}



static const struct snd_malloc_ops snd_dma_dev_ops = {

	.alloc = snd_dma_dev_alloc,

	.free = snd_dma_dev_free,

	.mmap = snd_dma_dev_mmap,

};

#endif /* CONFIG_HAS_DMA */

sound/core/memalloc_local.h

+1 −0
Original line number Diff line number Diff line
@@ -9,6 +9,7 @@ struct snd_malloc_ops { 
	struct page *(*get_page)(struct snd_dma_buffer *dmab, size_t offset);

	unsigned int (*get_chunk_size)(struct snd_dma_buffer *dmab,

				       unsigned int ofs, unsigned int size);

	int (*mmap)(struct snd_dma_buffer *dmab, struct vm_area_struct *area);

};



#ifdef CONFIG_SND_DMA_SGBUF

sound/core/pcm_native.c

+3 −16
Original line number Diff line number Diff line
@@ -3700,22 +3700,9 @@ int snd_pcm_lib_default_mmap(struct snd_pcm_substream *substream, 
			     struct vm_area_struct *area)

{

	area->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;

#ifdef CONFIG_GENERIC_ALLOCATOR

	if (substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV_IRAM) {

		area->vm_page_prot = pgprot_writecombine(area->vm_page_prot);

		return remap_pfn_range(area, area->vm_start,

				substream->dma_buffer.addr >> PAGE_SHIFT,

				area->vm_end - area->vm_start, area->vm_page_prot);

	}

#endif /* CONFIG_GENERIC_ALLOCATOR */

	if (IS_ENABLED(CONFIG_HAS_DMA) && !substream->ops->page &&

	    (substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV ||

	     substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV_UC))

		return dma_mmap_coherent(substream->dma_buffer.dev.dev,

					 area,

					 substream->runtime->dma_area,

					 substream->runtime->dma_addr,

					 substream->runtime->dma_bytes);

	if (!substream->ops->page &&

	    !snd_dma_buffer_mmap(snd_pcm_get_dma_buf(substream), area))

		return 0;

	/* mmap with fault handler */

	area->vm_ops = &snd_pcm_vm_ops_data_fault;

	return 0;