[PATCH] staging: media: atomisp: Convert kmap() to kmap_local_page()

[PATCH] staging: media: atomisp: Convert kmap() to kmap_local_page()

[Fabio M. De Francesco]

The use of kmap() is being deprecated in favor of kmap_local_page() where
it is feasible. With kmap_local_page(), the mapping is per thread, CPU
local and not globally visible.

load_and_flush_by_kmap() is a function where the use of kmap_local_page()
in place of kmap() is correctly suited.

Convert load_and_flush_by_kmap() from kmap() to kmap_local_page().

Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
---
 drivers/staging/media/atomisp/pci/hmm/hmm.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/media/atomisp/pci/hmm/hmm.c b/drivers/staging/media/atomisp/pci/hmm/hmm.c
index c1cda16f2dc0..6394385b6637 100644
--- a/drivers/staging/media/atomisp/pci/hmm/hmm.c
+++ b/drivers/staging/media/atomisp/pci/hmm/hmm.c
@@ -350,7 +350,7 @@ static int load_and_flush_by_kmap(ia_css_ptr virt, void *data,
 		idx = (virt - bo->start) >> PAGE_SHIFT;
 		offset = (virt - bo->start) - (idx << PAGE_SHIFT);
 
-		src = (char *)kmap(bo->page_obj[idx].page) + offset;
+		src = (char *)kmap_local_page(bo->page_obj[idx].page) + offset;
 
 		if ((bytes + offset) >= PAGE_SIZE) {
 			len = PAGE_SIZE - offset;
@@ -369,7 +369,7 @@ static int load_and_flush_by_kmap(ia_css_ptr virt, void *data,
 
 		clflush_cache_range(src, len);
 
-		kunmap(bo->page_obj[idx].page);
+		kunmap_local(src);
 	}
 
 	return 0;
-- 
2.34.1

Re: [PATCH] staging: media: atomisp: Convert kmap() to kmap_local_page()

[Hans de Goede]

Hi,

On 4/9/22 00:31, Fabio M. De Francesco wrote:
> The use of kmap() is being deprecated in favor of kmap_local_page() where
> it is feasible. With kmap_local_page(), the mapping is per thread, CPU
> local and not globally visible.
> 
> load_and_flush_by_kmap() is a function where the use of kmap_local_page()
> in place of kmap() is correctly suited.
> 
> Convert load_and_flush_by_kmap() from kmap() to kmap_local_page().
> 
> Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>

I've successfully tested this on both the front and back cams
of a chuwi hi8 tablet:

Tested-by: Hans de Goede <hdegoede@redhat.com>

Regards,

Hans



> ---
>  drivers/staging/media/atomisp/pci/hmm/hmm.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/staging/media/atomisp/pci/hmm/hmm.c b/drivers/staging/media/atomisp/pci/hmm/hmm.c
> index c1cda16f2dc0..6394385b6637 100644
> --- a/drivers/staging/media/atomisp/pci/hmm/hmm.c
> +++ b/drivers/staging/media/atomisp/pci/hmm/hmm.c
> @@ -350,7 +350,7 @@ static int load_and_flush_by_kmap(ia_css_ptr virt, void *data,
>  		idx = (virt - bo->start) >> PAGE_SHIFT;
>  		offset = (virt - bo->start) - (idx << PAGE_SHIFT);
>  
> -		src = (char *)kmap(bo->page_obj[idx].page) + offset;
> +		src = (char *)kmap_local_page(bo->page_obj[idx].page) + offset;
>  
>  		if ((bytes + offset) >= PAGE_SIZE) {
>  			len = PAGE_SIZE - offset;
> @@ -369,7 +369,7 @@ static int load_and_flush_by_kmap(ia_css_ptr virt, void *data,
>  
>  		clflush_cache_range(src, len);
>  
> -		kunmap(bo->page_obj[idx].page);
> +		kunmap_local(src);
>  	}
>  
>  	return 0;