[PATCH v2 03/15] arm64: pgtable: use mmu gather to free p4d level page table

[Qi Zheng <zhengqi.arch@bytedance.com>]

Like other levels of page tables, also use mmu gather mechanism to free
p4d level page table.

Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Originally-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: linux-arm-kernel@lists.infradead.org
---
 arch/arm64/include/asm/pgalloc.h |  2 --
 arch/arm64/include/asm/tlb.h     | 14 ++++++++++++++
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/include/asm/pgalloc.h b/arch/arm64/include/asm/pgalloc.h
index 679c530549327..58cc260b6bee8 100644
--- a/arch/arm64/include/asm/pgalloc.h
+++ b/arch/arm64/include/asm/pgalloc.h
@@ -100,8 +100,6 @@ static inline void p4d_free(struct mm_struct *mm, p4d_t *p4d)
 	if (pgtable_l5_enabled())
 		__p4d_free(mm, p4d);
 }
-
-#define __p4d_free_tlb(tlb, p4d, addr)  p4d_free((tlb)->mm, p4d)
 #else
 static inline void __pgd_populate(pgd_t *pgdp, phys_addr_t p4dp, pgdval_t prot)
 {
diff --git a/arch/arm64/include/asm/tlb.h b/arch/arm64/include/asm/tlb.h
index a947c6e784ed2..445282cde9afb 100644
--- a/arch/arm64/include/asm/tlb.h
+++ b/arch/arm64/include/asm/tlb.h
@@ -111,4 +111,18 @@ static inline void __pud_free_tlb(struct mmu_gather *tlb, pud_t *pudp,
 }
 #endif
 
+#if CONFIG_PGTABLE_LEVELS > 4
+static inline void __p4d_free_tlb(struct mmu_gather *tlb, p4d_t *p4dp,
+				  unsigned long addr)
+{
+	struct ptdesc *ptdesc = virt_to_ptdesc(p4dp);
+
+	if (!pgtable_l5_enabled())
+		return;
+
+	pagetable_p4d_dtor(ptdesc);
+	tlb_remove_ptdesc(tlb, ptdesc);
+}
+#endif
+
 #endif
-- 
2.20.1