[PATCH 14/17] ia64/tlb: Fix __p*_free_tlb()

From: Peter Zijlstra
Date: Wed Dec 11 2019 - 07:32:12 EST


Just like regular pages, page directories need to observe the
following order:

1) unhook
2) TLB invalidate
3) free

to ensure it is safe against concurrent accesses.

Since IA64 has page based P[UM]Ds, no software walkers and IPI based
TLB invalidation, it can use the simple tlb_remove_page() based
freeer.

Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
arch/ia64/include/asm/pgalloc.h | 13 ++++++++++---
1 file changed, 10 insertions(+), 3 deletions(-)

--- a/arch/ia64/include/asm/pgalloc.h
+++ b/arch/ia64/include/asm/pgalloc.h
@@ -50,7 +50,9 @@ static inline void pud_free(struct mm_st
{
free_page((unsigned long)pud);
}
-#define __pud_free_tlb(tlb, pud, address) pud_free((tlb)->mm, pud)
+
+#define __pud_free_tlb(tlb, pud, address) \
+ tlb_remove_table((tlb), virt_to_page(pud))
#endif /* CONFIG_PGTABLE_LEVELS == 4 */

static inline void
@@ -69,7 +71,8 @@ static inline void pmd_free(struct mm_st
free_page((unsigned long)pmd);
}

-#define __pmd_free_tlb(tlb, pmd, address) pmd_free((tlb)->mm, pmd)
+#define __pmd_free_tlb(tlb, pmd, address) \
+ tlb_remove_table((tlb), virt_to_page(pmd)

static inline void
pmd_populate(struct mm_struct *mm, pmd_t * pmd_entry, pgtable_t pte)
@@ -84,6 +87,10 @@ pmd_populate_kernel(struct mm_struct *mm
pmd_val(*pmd_entry) = __pa(pte);
}

-#define __pte_free_tlb(tlb, pte, address) pte_free((tlb)->mm, pte)
+#define __pte_free_tlb(tlb, pte, address) \
+do { \
+ pgtable_pte_page_dtor(pte); \
+ tlb_remove_table((tlb), (pte)); \
+} while (0)

#endif /* _ASM_IA64_PGALLOC_H */