diff mbox

[RFC,v6,2/7] dma: Add simple dma_noop_mmap

Message ID 1486113624-7494-2-git-send-email-alexandre.torgue@st.com (mailing list archive)
State New, archived
Headers show

Commit Message

Alexandre TORGUE Feb. 3, 2017, 9:20 a.m. UTC
From: Vladimir Murzin <vladimir.murzin@arm.com>

This patch adds a simple implementation of mmap to dma_noop_ops.

Cc: Joerg Roedel <jroedel@suse.de>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Reported-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Tested-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Tested-by: Andras Szemzo <sza@esh.hu>
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
---
 lib/dma-noop.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

-- 2.0.0

Comments

Alexandre TORGUE Feb. 3, 2017, 9:22 a.m. UTC | #1
Hi,

Apologize for this bad sent.
Please forget it.

regards

On 02/03/2017 10:20 AM, Alexandre TORGUE wrote:
> From: Vladimir Murzin <vladimir.murzin@arm.com>
>
> This patch adds a simple implementation of mmap to dma_noop_ops.
>
> Cc: Joerg Roedel <jroedel@suse.de>
> Cc: Christian Borntraeger <borntraeger@de.ibm.com>
> Reported-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
> Tested-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
> Tested-by: Andras Szemzo <sza@esh.hu>
> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
> ---
>  lib/dma-noop.c | 21 +++++++++++++++++++++
>  1 file changed, 21 insertions(+)
>
> diff --git a/lib/dma-noop.c b/lib/dma-noop.c
> index a14eee5..70504eb 100644
> --- a/lib/dma-noop.c
> +++ b/lib/dma-noop.c
> @@ -66,6 +66,26 @@ static int dma_noop_supported(struct device *dev, u64 mask)
>  	return 1;
>  }
>
> +static int dma_noop_mmap(struct device *dev, struct vm_area_struct *vma,
> +			 void *cpu_addr, dma_addr_t dma_addr, size_t size,
> +			 unsigned long attrs)
> +{
> +	unsigned long user_count = vma_pages(vma);
> +	unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
> +	unsigned long pfn = page_to_pfn(virt_to_page(cpu_addr));
> +	unsigned long off = vma->vm_pgoff;
> +	int ret = -ENXIO;
> +
> +	if (off < count && user_count <= (count - off)) {
> +		ret = remap_pfn_range(vma, vma->vm_start,
> +				      pfn + off,
> +				      user_count << PAGE_SHIFT,
> +				      vma->vm_page_prot);
> +	}
> +
> +	return ret;
> +}
> +
>  struct dma_map_ops dma_noop_ops = {
>  	.alloc			= dma_noop_alloc,
>  	.free			= dma_noop_free,
> @@ -73,6 +93,7 @@ struct dma_map_ops dma_noop_ops = {
>  	.map_sg			= dma_noop_map_sg,
>  	.mapping_error		= dma_noop_mapping_error,
>  	.dma_supported		= dma_noop_supported,
> +	.mmap			= dma_noop_mmap,
>  };
>
>  EXPORT_SYMBOL(dma_noop_ops);
> -- 2.0.0
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>
diff mbox

Patch

diff --git a/lib/dma-noop.c b/lib/dma-noop.c
index a14eee5..70504eb 100644
--- a/lib/dma-noop.c
+++ b/lib/dma-noop.c
@@ -66,6 +66,26 @@  static int dma_noop_supported(struct device *dev, u64 mask)
 	return 1;
 }
 
+static int dma_noop_mmap(struct device *dev, struct vm_area_struct *vma,
+			 void *cpu_addr, dma_addr_t dma_addr, size_t size,
+			 unsigned long attrs)
+{
+	unsigned long user_count = vma_pages(vma);
+	unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
+	unsigned long pfn = page_to_pfn(virt_to_page(cpu_addr));
+	unsigned long off = vma->vm_pgoff;
+	int ret = -ENXIO;
+
+	if (off < count && user_count <= (count - off)) {
+		ret = remap_pfn_range(vma, vma->vm_start,
+				      pfn + off,
+				      user_count << PAGE_SHIFT,
+				      vma->vm_page_prot);
+	}
+
+	return ret;
+}
+
 struct dma_map_ops dma_noop_ops = {
 	.alloc			= dma_noop_alloc,
 	.free			= dma_noop_free,
@@ -73,6 +93,7 @@  struct dma_map_ops dma_noop_ops = {
 	.map_sg			= dma_noop_map_sg,
 	.mapping_error		= dma_noop_mapping_error,
 	.dma_supported		= dma_noop_supported,
+	.mmap			= dma_noop_mmap,
 };
 
 EXPORT_SYMBOL(dma_noop_ops);