2024-01-28 12:00:10

by Alexandre Ghiti

[permalink] [raw]
Subject: [PATCH] riscv: Implement pte_accessible()

Like other architectures, a pte is accessible if it is present or if
there is a pending tlb flush and the pte is protnone (which could be the
case when a pte is downgraded to protnone before a flush tlb is
executed).

Signed-off-by: Alexandre Ghiti <[email protected]>
---
arch/riscv/include/asm/pgtable.h | 13 +++++++++++++
1 file changed, 13 insertions(+)

diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
index 0c94260b5d0c..3b46677827f6 100644
--- a/arch/riscv/include/asm/pgtable.h
+++ b/arch/riscv/include/asm/pgtable.h
@@ -353,6 +353,19 @@ static inline int pte_present(pte_t pte)
return (pte_val(pte) & (_PAGE_PRESENT | _PAGE_PROT_NONE));
}

+#define pte_accessible pte_accessible
+static inline unsigned long pte_accessible(struct mm_struct *mm, pte_t a)
+{
+ if (pte_val(a) & _PAGE_PRESENT)
+ return true;
+
+ if ((pte_val(a) & _PAGE_PROT_NONE) &&
+ atomic_read(&mm->tlb_flush_pending))
+ return true;
+
+ return false;
+}
+
static inline int pte_none(pte_t pte)
{
return (pte_val(pte) == 0);
--
2.39.2