[PATCH 09/12] asm-generic/page.h: Make pfn accessors static inlines

Linus Walleij
2023-05-11T12:01:03Z

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 we do the same change for pfn_to_virt.

Immediately define virt_to_pfn and pfn_to_virt to the static
inline after the static inline since this style of defining
functions is used for the generic helpers.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---
include/asm-generic/page.h | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/include/asm-generic/page.h b/include/asm-generic/page.h
index c0be2edeb484..e8ef12bb858c 100644
--- a/include/asm-generic/page.h
+++ b/include/asm-generic/page.h
@@ -74,8 +74,16 @@ extern unsigned long memory_end;
#define __va(x) ((void *)((unsigned long) (x)))
#define __pa(x) ((unsigned long) (x))

-#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;
+}
+#define virt_to_pfn virt_to_pfn
+static inline void * pfn_to_virt(unsigned long pfn)
+{
+ return __va(pfn) << PAGE_SHIFT;
+}
+#define pfn_to_virt pfn_to_virt

#define virt_to_page(addr) pfn_to_page(virt_to_pfn(addr))
#define page_to_virt(page) pfn_to_virt(page_to_pfn(page))

--
2.34.1