All of lore.kernel.org
 help / color / mirror / Atom feed
* [PATCH] staging: media: atomisp: Use kmap_local_page() in hmm_set()
@ 2022-04-13 21:22 Fabio M. De Francesco
  2022-04-13 22:24 ` Ira Weiny
  2022-04-20 11:07 ` Hans de Goede
  0 siblings, 2 replies; 3+ messages in thread
From: Fabio M. De Francesco @ 2022-04-13 21:22 UTC (permalink / raw)
  To: Mauro Carvalho Chehab, Sakari Ailus, Greg Kroah-Hartman,
	Hans Verkuil, Tsuchiya Yuto, Martiros Shakhzadyan, Hans de Goede,
	linux-media, linux-staging, linux-kernel, Ira Weiny, outreachy
  Cc: Fabio M. De Francesco

The use of kmap() is being deprecated in favor of kmap_local_page()
where it is feasible. In file pci/hmm/hmm.c, function hmm_set() calls
kmap() / kunmap() where kmap_local_page() can instead do the mapping.

With kmap_local_page(), the mapping is per thread, CPU local and not
globally visible. Therefore, hmm_set()() is a function where the use
of kmap_local_page() in place of kmap() is correctly suited.

Convert the calls of kmap() / kunmap() to kmap_local_page() /
kunmap_local().

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 6394385b6637..46ac082cd3f1 100644
--- a/drivers/staging/media/atomisp/pci/hmm/hmm.c
+++ b/drivers/staging/media/atomisp/pci/hmm/hmm.c
@@ -563,7 +563,7 @@ int hmm_set(ia_css_ptr virt, int c, unsigned int bytes)
 		idx = (virt - bo->start) >> PAGE_SHIFT;
 		offset = (virt - bo->start) - (idx << PAGE_SHIFT);
 
-		des = (char *)kmap(bo->page_obj[idx].page) + offset;
+		des = (char *)kmap_local_page(bo->page_obj[idx].page) + offset;
 
 		if ((bytes + offset) >= PAGE_SIZE) {
 			len = PAGE_SIZE - offset;
@@ -579,7 +579,7 @@ int hmm_set(ia_css_ptr virt, int c, unsigned int bytes)
 
 		clflush_cache_range(des, len);
 
-		kunmap(bo->page_obj[idx].page);
+		kunmap_local(des);
 	}
 
 	return 0;
-- 
2.34.1


^ permalink raw reply related	[flat|nested] 3+ messages in thread
* Re: [PATCH] staging: media: atomisp: Use kmap_local_page() in hmm_set()
  2022-04-13 21:22 [PATCH] staging: media: atomisp: Use kmap_local_page() in hmm_set() Fabio M. De Francesco
@ 2022-04-13 22:24 ` Ira Weiny
  2022-04-20 11:07 ` Hans de Goede
  1 sibling, 0 replies; 3+ messages in thread
From: Ira Weiny @ 2022-04-13 22:24 UTC (permalink / raw)
  To: Fabio M. De Francesco
  Cc: Mauro Carvalho Chehab, Sakari Ailus, Greg Kroah-Hartman,
	Hans Verkuil, Tsuchiya Yuto, Martiros Shakhzadyan, Hans de Goede,
	linux-media, linux-staging, linux-kernel, outreachy

On Wed, Apr 13, 2022 at 11:22:10PM +0200, Fabio M. De Francesco wrote:
> The use of kmap() is being deprecated in favor of kmap_local_page()
> where it is feasible. In file pci/hmm/hmm.c, function hmm_set() calls
> kmap() / kunmap() where kmap_local_page() can instead do the mapping.
> 
> With kmap_local_page(), the mapping is per thread, CPU local and not
> globally visible. Therefore, hmm_set()() is a function where the use
> of kmap_local_page() in place of kmap() is correctly suited.
> 
> Convert the calls of kmap() / kunmap() to kmap_local_page() /
> kunmap_local().
> 
> Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>

Reviewed-by: Ira Weiny <ira.weiny@intel.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 6394385b6637..46ac082cd3f1 100644
> --- a/drivers/staging/media/atomisp/pci/hmm/hmm.c
> +++ b/drivers/staging/media/atomisp/pci/hmm/hmm.c
> @@ -563,7 +563,7 @@ int hmm_set(ia_css_ptr virt, int c, unsigned int bytes)
>  		idx = (virt - bo->start) >> PAGE_SHIFT;
>  		offset = (virt - bo->start) - (idx << PAGE_SHIFT);
>  
> -		des = (char *)kmap(bo->page_obj[idx].page) + offset;
> +		des = (char *)kmap_local_page(bo->page_obj[idx].page) + offset;
>  
>  		if ((bytes + offset) >= PAGE_SIZE) {
>  			len = PAGE_SIZE - offset;
> @@ -579,7 +579,7 @@ int hmm_set(ia_css_ptr virt, int c, unsigned int bytes)
>  
>  		clflush_cache_range(des, len);
>  
> -		kunmap(bo->page_obj[idx].page);
> +		kunmap_local(des);
>  	}
>  
>  	return 0;
> -- 
> 2.34.1
> 

^ permalink raw reply	[flat|nested] 3+ messages in thread
* Re: [PATCH] staging: media: atomisp: Use kmap_local_page() in hmm_set()
  2022-04-13 21:22 [PATCH] staging: media: atomisp: Use kmap_local_page() in hmm_set() Fabio M. De Francesco
  2022-04-13 22:24 ` Ira Weiny
@ 2022-04-20 11:07 ` Hans de Goede
  1 sibling, 0 replies; 3+ messages in thread
From: Hans de Goede @ 2022-04-20 11:07 UTC (permalink / raw)
  To: Fabio M. De Francesco, Mauro Carvalho Chehab, Sakari Ailus,
	Greg Kroah-Hartman, Hans Verkuil, Tsuchiya Yuto,
	Martiros Shakhzadyan, linux-media, linux-staging, linux-kernel,
	Ira Weiny, outreachy

Hi,

On 4/13/22 23:22, Fabio M. De Francesco wrote:
> The use of kmap() is being deprecated in favor of kmap_local_page()
> where it is feasible. In file pci/hmm/hmm.c, function hmm_set() calls
> kmap() / kunmap() where kmap_local_page() can instead do the mapping.
> 
> With kmap_local_page(), the mapping is per thread, CPU local and not
> globally visible. Therefore, hmm_set()() is a function where the use
> of kmap_local_page() in place of kmap() is correctly suited.
> 
> Convert the calls of kmap() / kunmap() to kmap_local_page() /
> kunmap_local().
> 
> 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 6394385b6637..46ac082cd3f1 100644
> --- a/drivers/staging/media/atomisp/pci/hmm/hmm.c
> +++ b/drivers/staging/media/atomisp/pci/hmm/hmm.c
> @@ -563,7 +563,7 @@ int hmm_set(ia_css_ptr virt, int c, unsigned int bytes)
>  		idx = (virt - bo->start) >> PAGE_SHIFT;
>  		offset = (virt - bo->start) - (idx << PAGE_SHIFT);
>  
> -		des = (char *)kmap(bo->page_obj[idx].page) + offset;
> +		des = (char *)kmap_local_page(bo->page_obj[idx].page) + offset;
>  
>  		if ((bytes + offset) >= PAGE_SIZE) {
>  			len = PAGE_SIZE - offset;
> @@ -579,7 +579,7 @@ int hmm_set(ia_css_ptr virt, int c, unsigned int bytes)
>  
>  		clflush_cache_range(des, len);
>  
> -		kunmap(bo->page_obj[idx].page);
> +		kunmap_local(des);
>  	}
>  
>  	return 0;


^ permalink raw reply	[flat|nested] 3+ messages in thread
end of thread, other threads:[~2022-04-20 11:07 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-04-13 21:22 [PATCH] staging: media: atomisp: Use kmap_local_page() in hmm_set() Fabio M. De Francesco
2022-04-13 22:24 ` Ira Weiny
2022-04-20 11:07 ` Hans de Goede

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.