2022-04-14 15:22:12

by Fabio M. De Francesco

Subject: [PATCH] staging: media: atomisp: Use kmap_local_page() in hmm_set()

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 <[email protected]>
---
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

2022-04-14 15:24:41

by Ira Weiny

Subject: Re: [PATCH] staging: media: atomisp: Use kmap_local_page() in hmm_set()

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 <[email protected]>

Reviewed-by: Ira Weiny <[email protected]>

> ---
> 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
>

2022-04-22 14:45:13

by Hans de Goede

Subject: Re: [PATCH] staging: media: atomisp: Use kmap_local_page() in hmm_set()

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 <[email protected]>


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

Tested-by: Hans de Goede <[email protected]>

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;