Re: [PATCH 02/12] m68k: Pass a pointer to virt_to_pfn() virt_to_page()

Geert Uytterhoeven
2023-05-12T09:56:33Z

Hi Linus,

On Thu, May 11, 2023 at 1:59 PM Linus Walleij <linus.walleij@linaro.org> wrote:
> Functions that work on a pointer to virtual memory such as
> virt_to_pfn() and users of that function such as
> virt_to_page() are supposed to pass a pointer to virtual
> memory, ideally a (void *) or other pointer. However since
> many architectures implement virt_to_pfn() as a macro,
> this function becomes polymorphic and accepts both a
> (unsigned long) and a (void *).
>
> Fix up the offending calls in arch/m68k with explicit casts.
>
> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
> ---
> ChangeLog v1->v2:
> - Add an extra parens around the page argument to the
> PD_PTABLE() macro, as is normally required.

Thanks for the update!

To build sun3_defconfig and m5475evb_defconfig cleanly, you need to
include the (Gmail-whitespace-damaged) changes below.
These were compile-tested only.

diff --git a/arch/m68k/include/asm/mcf_pgtable.h
b/arch/m68k/include/asm/mcf_pgtable.h
index 96d069829803505c..46ae379bb14d5e05 100644
--- a/arch/m68k/include/asm/mcf_pgtable.h
+++ b/arch/m68k/include/asm/mcf_pgtable.h
@@ -135,7 +135,7 @@ static inline void pte_clear(struct mm_struct *mm,
unsigned long addr,
}

#define pte_pagenr(pte) ((__pte_page(pte) - PAGE_OFFSET) >> PAGE_SHIFT)
-#define pte_page(pte) virt_to_page(__pte_page(pte))
+#define pte_page(pte) virt_to_page((void *)__pte_page(pte))

static inline int pmd_none2(pmd_t *pmd) { return !pmd_val(*pmd); }
#define pmd_none(pmd) pmd_none2(&(pmd))
diff --git a/arch/m68k/include/asm/sun3_pgtable.h
b/arch/m68k/include/asm/sun3_pgtable.h
index e582b0484a55cd82..f3e7728f58cd9dd0 100644
--- a/arch/m68k/include/asm/sun3_pgtable.h
+++ b/arch/m68k/include/asm/sun3_pgtable.h
@@ -109,9 +109,9 @@ static inline void pte_clear (struct mm_struct
*mm, unsigned long addr, pte_t *p
#define pfn_pte(pfn, pgprot) \
({ pte_t __pte; pte_val(__pte) = pfn | pgprot_val(pgprot); __pte; })

-#define pte_page(pte) virt_to_page(__pte_page(pte))
+#define pte_page(pte) virt_to_page((void *)__pte_page(pte))
#define pmd_pfn(pmd) (pmd_val(pmd) >> PAGE_SHIFT)
-#define pmd_page(pmd) virt_to_page(pmd_page_vaddr(pmd))
+#define pmd_page(pmd) virt_to_page((void *)pmd_page_vaddr(pmd))

static inline int pmd_none2 (pmd_t *pmd) { return !pmd_val (*pmd); }
diff --git a/arch/m68k/mm/mcfmmu.c b/arch/m68k/mm/mcfmmu.c
index 70aa0979e02710a8..a4c552c7e2c8ca12 100644
--- a/arch/m68k/mm/mcfmmu.c
+++ b/arch/m68k/mm/mcfmmu.c
@@ -69,7 +69,7 @@ void __init paging_init(void)

/* now change pg_table to kernel virtual addresses */
for (i = 0; i < PTRS_PER_PTE; ++i, ++pg_table) {
- pte_t pte = pfn_pte(virt_to_pfn(address), PAGE_INIT);
+ pte_t pte = pfn_pte(virt_to_pfn((void
*)address), PAGE_INIT);
if (address >= (unsigned long) high_memory)
pte_val(pte) = 0;

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds