s390/mm: 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.

For symmetry do the same with pfn_to_virt() reflecting the
current layout in asm-generic/page.h.

Doing this reveals a number of offenders in the arch code and
the S390-specific drivers, so just bite the bullet and fix up
all of those as well.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Link: https://lore.kernel.org/r/20230812-virt-to-phys-s390-v2-1-6c40f31fe36f@linaro.org
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

4 files changed, 13 insertions, 5 deletions

diff --git a/arch/s390/include/asm/kfence.h b/arch/s390/include/asm/kfence.h
index d55ba878378b..e47fd8cbe701 100644
--- a/arch/s390/include/asm/kfence.h
+++ b/arch/s390/include/asm/kfence.h
@@ -35,7 +35,7 @@ static __always_inline void kfence_split_mapping(void)
 
 static inline bool kfence_protect_page(unsigned long addr, bool protect)
 {
-	__kernel_map_pages(virt_to_page(addr), 1, !protect);
+	__kernel_map_pages(virt_to_page((void *)addr), 1, !protect);
 	return true;
 }
 
diff --git a/arch/s390/include/asm/page.h b/arch/s390/include/asm/page.h
index a9c138fcd2ad..cfec0743314e 100644
--- a/arch/s390/include/asm/page.h
+++ b/arch/s390/include/asm/page.h
@@ -191,8 +191,16 @@ int arch_make_page_accessible(struct page *page);
 #define phys_to_page(phys)	pfn_to_page(phys_to_pfn(phys))
 #define page_to_phys(page)	pfn_to_phys(page_to_pfn(page))
 
-#define pfn_to_virt(pfn)	__va(pfn_to_phys(pfn))
-#define virt_to_pfn(kaddr)	(phys_to_pfn(__pa(kaddr)))
+static inline void *pfn_to_virt(unsigned long pfn)
+{
+	return __va(pfn_to_phys(pfn));
+}
+
+static inline unsigned long virt_to_pfn(const void *kaddr)
+{
+	return phys_to_pfn(__pa(kaddr));
+}
+
 #define pfn_to_kaddr(pfn)	pfn_to_virt(pfn)
 
 #define virt_to_page(kaddr)	pfn_to_page(virt_to_pfn(kaddr))
diff --git a/arch/s390/mm/cmm.c b/arch/s390/mm/cmm.c
index 5300c6867d5e..f47515313226 100644
--- a/arch/s390/mm/cmm.c
+++ b/arch/s390/mm/cmm.c
@@ -90,7 +90,7 @@ static long cmm_alloc_pages(long nr, long *counter,
 			} else
 				free_page((unsigned long) npa);
 		}
-		diag10_range(virt_to_pfn(addr), 1);
+		diag10_range(virt_to_pfn((void *)addr), 1);
 		pa->pages[pa->index++] = addr;
 		(*counter)++;
 		spin_unlock(&cmm_lock);
diff --git a/arch/s390/mm/vmem.c b/arch/s390/mm/vmem.c
index be69cb2d47eb..3391efb59641 100644
--- a/arch/s390/mm/vmem.c
+++ b/arch/s390/mm/vmem.c
@@ -36,7 +36,7 @@ static void vmem_free_pages(unsigned long addr, int order)
 {
 	/* We don't expect boot memory to be removed ever. */
 	if (!slab_is_available() ||
-	    WARN_ON_ONCE(PageReserved(virt_to_page(addr))))
+	    WARN_ON_ONCE(PageReserved(virt_to_page((void *)addr))))
 		return;
 	free_pages(addr, order);
 }