[PATCH 2/4] m68k: mm: Convert free_pointer_table() to use ptdescs

Vishal Moola (Oracle) posted 4 patches 4 months ago
[PATCH 2/4] m68k: mm: Convert free_pointer_table() to use ptdescs
Posted by Vishal Moola (Oracle) 4 months ago
Motorola uses free_pointer_table() for page tables, so it should be using
struct ptdesc, not struct page.

This helps us prepare to allocate ptdescs as their own memory
descriptor, and prepares to remove a user of page->lru.

Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
---
 arch/m68k/mm/motorola.c | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/arch/m68k/mm/motorola.c b/arch/m68k/mm/motorola.c
index 35c3571ffbef..6a459710b2a7 100644
--- a/arch/m68k/mm/motorola.c
+++ b/arch/m68k/mm/motorola.c
@@ -200,21 +200,20 @@ int free_pointer_table(void *table, int type)
 {
 	ptable_desc *dp;
 	unsigned long ptable = (unsigned long)table;
-	unsigned long page = ptable & PAGE_MASK;
-	unsigned int mask = 1U << ((ptable - page)/ptable_size(type));
+	unsigned long pt_addr = ptable & PAGE_MASK;
+	unsigned int mask = 1U << ((ptable - pt_addr)/ptable_size(type));
 
-	dp = PD_PTABLE(page);
+	dp = PD_PTABLE(pt_addr);
 	if (PD_MARKBITS (dp) & mask)
 		panic ("table already free!");
 
 	PD_MARKBITS (dp) |= mask;
 
 	if (PD_MARKBITS(dp) == ptable_mask(type)) {
-		/* all tables in page are free, free page */
+		/* all tables in ptdesc are free, free ptdesc */
 		list_del(dp);
-		mmu_page_dtor((void *)page);
-		pagetable_dtor(virt_to_ptdesc((void *)page));
-		free_page (page);
+		mmu_page_dtor((void *)pt_addr);
+		pagetable_dtor_free(virt_to_ptdesc((void *)pt_addr));
 		return 1;
 	} else if (ptable_list[type].next != dp) {
 		/*
-- 
2.49.0
Re: [PATCH 2/4] m68k: mm: Convert free_pointer_table() to use ptdescs
Posted by Geert Uytterhoeven 3 months, 2 weeks ago
On Wed, 11 Jun 2025 at 02:13, Vishal Moola (Oracle)
<vishal.moola@gmail.com> wrote:
> Motorola uses free_pointer_table() for page tables, so it should be using
> struct ptdesc, not struct page.
>
> This helps us prepare to allocate ptdescs as their own memory
> descriptor, and prepares to remove a user of page->lru.
>
> Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>

Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
i.e. will queue in the m68k tree for v6.17.

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