[RFC PATCH v5 8/8] arm64: tlb: Set the TTL field in flush_tlb_range

[Zhenyu Ye]

This patch uses the cleared_* in struct mmu_gather to set the
TTL field in flush_tlb_range().

Signed-off-by: Zhenyu Ye <yezhenyu2@xxxxxxxxxx>
---
 arch/arm64/include/asm/tlb.h      | 39 ++++++++++++++++++++++++++++++-
 arch/arm64/include/asm/tlbflush.h | 22 +++++------------
 2 files changed, 44 insertions(+), 17 deletions(-)

diff --git a/arch/arm64/include/asm/tlb.h b/arch/arm64/include/asm/tlb.h
index b76df828e6b7..72b6e3763df2 100644
--- a/arch/arm64/include/asm/tlb.h
+++ b/arch/arm64/include/asm/tlb.h
@@ -21,11 +21,34 @@ static void tlb_flush(struct mmu_gather *tlb);
 
 #include <asm-generic/tlb.h>
 
+/*
+ * get the tlbi levels in arm64.  Default value is 0 if more than one
+ * of cleared_* is set or neither is set.
+ * Arm64 doesn't support p4ds now.
+ */
+static inline int tlb_get_level(struct mmu_gather *tlb)
+{
+	int sum = tlb->cleared_ptes + tlb->cleared_pmds +
+		  tlb->cleared_puds + tlb->cleared_p4ds;
+
+	if (sum != 1)
+		return 0;
+	else if (tlb->cleared_ptes)
+		return 3;
+	else if (tlb->cleared_pmds)
+		return 2;
+	else if (tlb->cleared_puds)
+		return 1;
+
+	return 0;
+}
+
 static inline void tlb_flush(struct mmu_gather *tlb)
 {
 	struct vm_area_struct vma = TLB_FLUSH_VMA(tlb->mm, 0);
 	bool last_level = !tlb->freed_tables;
 	unsigned long stride = tlb_get_unmap_size(tlb);
+	int tlb_level = tlb_get_level(tlb);
 
 	/*
 	 * If we're tearing down the address space then we only care about
@@ -38,7 +61,21 @@ static inline void tlb_flush(struct mmu_gather *tlb)
 		return;
 	}
 
-	__flush_tlb_range(&vma, tlb->start, tlb->end, stride, last_level);
+	__flush_tlb_range(&vma, tlb->start, tlb->end, stride,
+			  last_level, tlb_level);
+}
+
+static inline void flush_tlb_range(struct mmu_gather *tlb,
+				   struct vm_area_struct *vma,
+				   unsigned long start, unsigned long end)
+{
+	/*
+	 * We cannot use leaf-only invalidation here, since we may be invalidating
+	 * table entries as part of collapsing hugepages or moving page tables.
+	 */
+	unsigned long stride = tlb_get_unmap_size(tlb);
+	int tlb_level = tlb_get_level(tlb);
+	__flush_tlb_range(vma, start, end, stride, false, tlb_level);
 }
 
 static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t pte,
diff --git a/arch/arm64/include/asm/tlbflush.h b/arch/arm64/include/asm/tlbflush.h
index 0b4d75a2270b..dc8e803692f8 100644
--- a/arch/arm64/include/asm/tlbflush.h
+++ b/arch/arm64/include/asm/tlbflush.h
@@ -215,7 +215,8 @@ static inline void flush_tlb_page(struct vm_area_struct *vma,
 
 static inline void __flush_tlb_range(struct vm_area_struct *vma,
 				     unsigned long start, unsigned long end,
-				     unsigned long stride, bool last_level)
+				     unsigned long stride, bool last_level,
+				     int tlb_level)
 {
 	unsigned long asid = ASID(vma->vm_mm);
 	unsigned long addr;
@@ -237,27 +238,16 @@ static inline void __flush_tlb_range(struct vm_area_struct *vma,
 	dsb(ishst);
 	for (addr = start; addr < end; addr += stride) {
 		if (last_level) {
-			__tlbi_level(vale1is, addr, 0);
-			__tlbi_user_level(vale1is, addr, 0);
+			__tlbi_level(vale1is, addr, tlb_level);
+			__tlbi_user_level(vale1is, addr, tlb_level);
 		} else {
-			__tlbi_level(vae1is, addr, 0);
-			__tlbi_user_level(vae1is, addr, 0);
+			__tlbi_level(vae1is, addr, tlb_level);
+			__tlbi_user_level(vae1is, addr, tlb_level);
 		}
 	}
 	dsb(ish);
 }
 
-static inline void flush_tlb_range(struct mmu_gather *tlb,
-				   struct vm_area_struct *vma,
-				   unsigned long start, unsigned long end)
-{
-	/*
-	 * We cannot use leaf-only invalidation here, since we may be invalidating
-	 * table entries as part of collapsing hugepages or moving page tables.
-	 */
-	__flush_tlb_range(vma, start, end, PAGE_SIZE, false);
-}
-
 static inline void flush_tlb_kernel_range(unsigned long start, unsigned long end)
 {
 	unsigned long addr;
-- 
2.19.1