powerpc: Make virt_to_pfn() a static inline

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.

Finally the KVM code in book3s_64_mmu_hv.c was passing an
unsigned int to virt_to_phys() so fix that up with a cast so the
result compiles.

Signed-off-by: Linus Walleij <[email protected]>
[mpe: Fixup kfence.h, simplify pfn_to_kaddr() & pmd_page_vaddr()]
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://msgid.link/[email protected]

1 files changed, 20 insertions, 10 deletions

diff --git a/arch/powerpc/include/asm/page.h b/arch/powerpc/include/asm/page.h
index f2b6bf5687d0..e5fcc79b5bfb 100644
--- a/arch/powerpc/include/asm/page.h
+++ b/arch/powerpc/include/asm/page.h
@@ -9,6 +9,7 @@
 #ifndef __ASSEMBLY__
 #include <linux/types.h>
 #include <linux/kernel.h>
+#include <linux/bug.h>
 #else
 #include <asm/types.h>
 #endif
@@ -119,16 +120,6 @@ extern long long virt_phys_offset;
 #define ARCH_PFN_OFFSET		((unsigned long)(MEMORY_START >> PAGE_SHIFT))
 #endif
 
-#define virt_to_pfn(kaddr)	(__pa(kaddr) >> PAGE_SHIFT)
-#define virt_to_page(kaddr)	pfn_to_page(virt_to_pfn(kaddr))
-#define pfn_to_kaddr(pfn)	__va((pfn) << PAGE_SHIFT)
-
-#define virt_addr_valid(vaddr)	({					\
-	unsigned long _addr = (unsigned long)vaddr;			\
-	_addr >= PAGE_OFFSET && _addr < (unsigned long)high_memory &&	\
-	pfn_valid(virt_to_pfn(_addr));					\
-})
-
 /*
  * On Book-E parts we need __va to parse the device tree and we can't
  * determine MEMORY_START until then.  However we can determine PHYSICAL_START
@@ -233,6 +224,25 @@ extern long long virt_phys_offset;
 #endif
 #endif
 
+#ifndef __ASSEMBLY__
+static inline unsigned long virt_to_pfn(const void *kaddr)
+{
+	return __pa(kaddr) >> PAGE_SHIFT;
+}
+
+static inline const void *pfn_to_kaddr(unsigned long pfn)
+{
+	return __va(pfn << PAGE_SHIFT);
+}
+#endif
+
+#define virt_to_page(kaddr)	pfn_to_page(virt_to_pfn(kaddr))
+#define virt_addr_valid(vaddr)	({					\
+	unsigned long _addr = (unsigned long)vaddr;			\
+	_addr >= PAGE_OFFSET && _addr < (unsigned long)high_memory &&	\
+	pfn_valid(virt_to_pfn((void *)_addr));				\
+})
+
 /*
  * Unfortunately the PLT is in the BSS in the PPC32 ELF ABI,
  * and needs to be executable.  This means the whole heap ends