Re: [PATCH] powerpc: Make virt_to_pfn() a static inline
From: Michael Ellerman <mpe@ellerman.id.au>
Date: 2023-08-15 07:32:07
Also in:
kvm, lkml
Linus Walleij [off-list ref] writes:
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. Move the virt_to_pfn() and related functions below the declaration of __pa() so it compiles. For symmetry do the same with pfn_to_kaddr(). As the file is included right into the linker file, we need to surround the functions with ifndef __ASSEMBLY__ so we don't cause compilation errors. The conversion moreover exposes the fact that pmd_page_vaddr() was returning an unsigned long rather than a const void * as could be expected, so all the sites defining pmd_page_vaddr() had to be augmented as well.
...
quoted hunk ↗ jump to hunk
diff --git a/arch/powerpc/include/asm/pgtable.h b/arch/powerpc/include/asm/pgtable.h index 6a88bfdaa69b..a9515d3d7831 100644 --- a/arch/powerpc/include/asm/pgtable.h +++ b/arch/powerpc/include/asm/pgtable.h@@ -60,9 +60,9 @@ static inline pgprot_t pte_pgprot(pte_t pte) } #ifndef pmd_page_vaddr -static inline unsigned long pmd_page_vaddr(pmd_t pmd) +static inline const void *pmd_page_vaddr(pmd_t pmd) { - return ((unsigned long)__va(pmd_val(pmd) & ~PMD_MASKED_BITS)); + return (const void *)((unsigned long)__va(pmd_val(pmd) & ~PMD_MASKED_BITS));
This can also just be: return __va(pmd_val(pmd) & ~PMD_MASKED_BITS); I've squashed that in. cheers