[PATCH v2] openrisc: Make pfn accessors statics inlines

[PATCH v2] openrisc: Make pfn accessors statics inlines

[Linus Walleij]

Making virt_to_pfn() a static inline taking a strongly typed
(const void *) makes the contract of a passing a pointer of that
type to the function explicit and exposes any misuse of the
macro virt_to_pfn() acting polymorphic and accepting many types
such as (void *), (unitptr_t) or (unsigned long) as arguments
without warnings.

For symmetry, do the same with pfn_to_virt().

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---
Changes in v2:
- Cast around a bit in the pfn_to_virt() function so we don't
  get pointer violation complaints.
- Link to v1: https://lore.kernel.org/r/20230808-virt-to-phys-openrisc-v1-1-b2c16cf000a8@linaro.org
---
 arch/openrisc/include/asm/page.h | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/arch/openrisc/include/asm/page.h b/arch/openrisc/include/asm/page.h
index 52b0d7e76446..44fc1fd56717 100644
--- a/arch/openrisc/include/asm/page.h
+++ b/arch/openrisc/include/asm/page.h
@@ -72,8 +72,15 @@ typedef struct page *pgtable_t;
 #define __va(x) ((void *)((unsigned long)(x) + PAGE_OFFSET))
 #define __pa(x) ((unsigned long) (x) - PAGE_OFFSET)
 
-#define virt_to_pfn(kaddr)      (__pa(kaddr) >> PAGE_SHIFT)
-#define pfn_to_virt(pfn)        __va((pfn) << PAGE_SHIFT)
+static inline unsigned long virt_to_pfn(const void *kaddr)
+{
+	return __pa(kaddr) >> PAGE_SHIFT;
+}
+
+static inline void * pfn_to_virt(unsigned long pfn)
+{
+	return (void *)((unsigned long)__va(pfn) << PAGE_SHIFT);
+}
 
 #define virt_to_page(addr) \
 	(mem_map + (((unsigned long)(addr)-PAGE_OFFSET) >> PAGE_SHIFT))

---
base-commit: 06c2afb862f9da8dc5efa4b6076a0e48c3fbaaa5
change-id: 20230808-virt-to-phys-openrisc-8ff05c233aef

Best regards,
-- 
Linus Walleij <linus.walleij@linaro.org>

Re: [PATCH v2] openrisc: Make pfn accessors statics inlines

[Stafford Horne]

On Fri, Aug 11, 2023 at 09:01:17AM +0200, Linus Walleij wrote:
> Making virt_to_pfn() a static inline taking a strongly typed
> (const void *) makes the contract of a passing a pointer of that
> type to the function explicit and exposes any misuse of the
> macro virt_to_pfn() acting polymorphic and accepting many types
> such as (void *), (unitptr_t) or (unsigned long) as arguments
> without warnings.
> 
> For symmetry, do the same with pfn_to_virt().
> 
> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
> ---
> Changes in v2:
> - Cast around a bit in the pfn_to_virt() function so we don't
>   get pointer violation complaints.
> - Link to v1: https://lore.kernel.org/r/20230808-virt-to-phys-openrisc-v1-1-b2c16cf000a8@linaro.org
> ---
>  arch/openrisc/include/asm/page.h | 11 +++++++++--
>  1 file changed, 9 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/openrisc/include/asm/page.h b/arch/openrisc/include/asm/page.h
> index 52b0d7e76446..44fc1fd56717 100644
> --- a/arch/openrisc/include/asm/page.h
> +++ b/arch/openrisc/include/asm/page.h
> @@ -72,8 +72,15 @@ typedef struct page *pgtable_t;
>  #define __va(x) ((void *)((unsigned long)(x) + PAGE_OFFSET))
>  #define __pa(x) ((unsigned long) (x) - PAGE_OFFSET)
>  
> -#define virt_to_pfn(kaddr)      (__pa(kaddr) >> PAGE_SHIFT)
> -#define pfn_to_virt(pfn)        __va((pfn) << PAGE_SHIFT)
> +static inline unsigned long virt_to_pfn(const void *kaddr)
> +{
> +	return __pa(kaddr) >> PAGE_SHIFT;
> +}
> +
> +static inline void * pfn_to_virt(unsigned long pfn)
> +{
> +	return (void *)((unsigned long)__va(pfn) << PAGE_SHIFT);
> +}
>  
>  #define virt_to_page(addr) \
>  	(mem_map + (((unsigned long)(addr)-PAGE_OFFSET) >> PAGE_SHIFT))
> 

Thanks, applied to my queue of patches for 6.6.

Note, I did some C=2 builds and booted 6.5-rc5 with this patch with no issues.

-Stafford