--- v7
+++ v4
@@ -1,23 +1,80 @@
-With two level page table don't enable move_normal_pud.
+Some architectures do have the concept of page walk cache which need
+to be flush when updating higher levels of page tables. A fast mremap
+that involves moving page table pages instead of copying pte entries
+should flush page walk cache since the old translation cache is no more
+valid.
+
+Add new helper flush_pte_tlb_pwc_range() which invalidates both TLB and
+page walk cache where TLB entries are mapped with page size PAGE_SIZE.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
- mm/mremap.c | 2 +-
- 1 file changed, 1 insertion(+), 1 deletion(-)
+ arch/powerpc/include/asm/book3s/64/tlbflush.h | 11 +++++++++++
+ mm/mremap.c | 15 +++++++++++++--
+ 2 files changed, 24 insertions(+), 2 deletions(-)
+diff --git a/arch/powerpc/include/asm/book3s/64/tlbflush.h b/arch/powerpc/include/asm/book3s/64/tlbflush.h
+index f9f8a3a264f7..c236b66f490b 100644
+--- a/arch/powerpc/include/asm/book3s/64/tlbflush.h
++++ b/arch/powerpc/include/asm/book3s/64/tlbflush.h
+@@ -80,6 +80,17 @@ static inline void flush_hugetlb_tlb_range(struct vm_area_struct *vma,
+ return flush_hugetlb_tlb_pwc_range(vma, start, end, false);
+ }
+
++#define flush_pte_tlb_pwc_range flush_tlb_pwc_range
++static inline void flush_pte_tlb_pwc_range(struct vm_area_struct *vma,
++ unsigned long start, unsigned long end,
++ bool also_pwc)
++{
++ if (radix_enabled())
++ return radix__flush_tlb_pwc_range_psize(vma->vm_mm, start,
++ end, mmu_virtual_psize, also_pwc);
++ return hash__flush_tlb_range(vma, start, end);
++}
++
+ static inline void flush_tlb_range(struct vm_area_struct *vma,
+ unsigned long start, unsigned long end)
+ {
diff --git a/mm/mremap.c b/mm/mremap.c
-index 92ab7d24a587..795a7d628b53 100644
+index 574287f9bb39..0e7b11daafee 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c
-@@ -276,7 +276,7 @@ static inline bool move_normal_pmd(struct vm_area_struct *vma,
+@@ -210,6 +210,17 @@ static void move_ptes(struct vm_area_struct *vma, pmd_t *old_pmd,
+ drop_rmap_locks(vma);
}
- #endif
--#ifdef CONFIG_HAVE_MOVE_PUD
-+#if CONFIG_PGTABLE_LEVELS > 2 && defined(CONFIG_HAVE_MOVE_PUD)
- static bool move_normal_pud(struct vm_area_struct *vma, unsigned long old_addr,
- unsigned long new_addr, pud_t *old_pud, pud_t *new_pud)
- {
++#ifndef flush_pte_tlb_pwc_range
++#define flush_pte_tlb_pwc_range flush_pte_tlb_pwc_range
++static inline void flush_pte_tlb_pwc_range(struct vm_area_struct *vma,
++ unsigned long start,
++ unsigned long end,
++ bool also_pwc)
++{
++ return flush_tlb_range(vma, start, end);
++}
++#endif
++
+ #ifdef CONFIG_HAVE_MOVE_PMD
+ static bool move_normal_pmd(struct vm_area_struct *vma, unsigned long old_addr,
+ unsigned long new_addr, pmd_t *old_pmd, pmd_t *new_pmd)
+@@ -260,7 +271,7 @@ static bool move_normal_pmd(struct vm_area_struct *vma, unsigned long old_addr,
+ VM_BUG_ON(!pmd_none(*new_pmd));
+ pmd_populate(mm, new_pmd, (pgtable_t)pmd_page_vaddr(pmd));
+
+- flush_tlb_range(vma, old_addr, old_addr + PMD_SIZE);
++ flush_pte_tlb_pwc_range(vma, old_addr, old_addr + PMD_SIZE, true);
+ if (new_ptl != old_ptl)
+ spin_unlock(new_ptl);
+ spin_unlock(old_ptl);
+@@ -307,7 +318,7 @@ static bool move_normal_pud(struct vm_area_struct *vma, unsigned long old_addr,
+ VM_BUG_ON(!pud_none(*new_pud));
+
+ pud_populate(mm, new_pud, (pmd_t *)pud_page_vaddr(pud));
+- flush_tlb_range(vma, old_addr, old_addr + PUD_SIZE);
++ flush_pte_tlb_pwc_range(vma, old_addr, old_addr + PUD_SIZE, true);
+ if (new_ptl != old_ptl)
+ spin_unlock(new_ptl);
+ spin_unlock(old_ptl);
--
-2.31.1
+2.30.2