powerpc/mm/radix: Add tlb flush of THP ptes

Instead of flushing the entire mm, implement a flush_pmd_tlb_range

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/include/asm/book3s/64/tlbflush-radix.h

@@ -12,6 +12,8 @@ static inline int mmu_get_ap(int psize)
 
 extern void radix__flush_tlb_range_psize(struct mm_struct *mm, unsigned long start,
 					 unsigned long end, int psize);
+extern void radix__flush_pmd_tlb_range(struct vm_area_struct *vma,
+				       unsigned long start, unsigned long end);
 extern void radix__flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
 			    unsigned long end);
 extern void radix__flush_tlb_kernel_range(unsigned long start, unsigned long end);

arch/powerpc/include/asm/book3s/64/tlbflush.h

@@ -7,6 +7,15 @@
 #include <asm/book3s/64/tlbflush-hash.h>
 #include <asm/book3s/64/tlbflush-radix.h>
 
+#define __HAVE_ARCH_FLUSH_PMD_TLB_RANGE
+static inline void flush_pmd_tlb_range(struct vm_area_struct *vma,
+				       unsigned long start, unsigned long end)
+{
+	if (radix_enabled())
+		return radix__flush_pmd_tlb_range(vma, start, end);
+	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)
 {

arch/powerpc/mm/pgtable-book3s64.c

@@ -33,7 +33,7 @@ int pmdp_set_access_flags(struct vm_area_struct *vma, unsigned long address,
 	changed = !pmd_same(*(pmdp), entry);
 	if (changed) {
 		__ptep_set_access_flags(pmdp_ptep(pmdp), pmd_pte(entry));
-		flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
+		flush_pmd_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
 	}
 	return changed;
 }
@@ -66,7 +66,7 @@ void pmdp_invalidate(struct vm_area_struct *vma, unsigned long address,
 		     pmd_t *pmdp)
 {
 	pmd_hugepage_update(vma->vm_mm, address, pmdp, _PAGE_PRESENT, 0);
-	flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
+	flush_pmd_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
 	/*
 	 * This ensures that generic code that rely on IRQ disabling
 	 * to prevent a parallel THP split work as expected.

arch/powerpc/mm/tlb-radix.c

@@ -391,3 +391,10 @@ void radix__flush_tlb_lpid(unsigned long lpid)
 	asm volatile("eieio; tlbsync; ptesync": : :"memory");
 }
 EXPORT_SYMBOL(radix__flush_tlb_lpid);
+
+void radix__flush_pmd_tlb_range(struct vm_area_struct *vma,
+				unsigned long start, unsigned long end)
+{
+	radix__flush_tlb_range_psize(vma->vm_mm, start, end, MMU_PAGE_2M);
+}
+EXPORT_SYMBOL(radix__flush_pmd_tlb_range);