powerpc/mm: add a helper to populate hugepd

This patchs adds a subarch helper to populate hugepd.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

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

@@ -100,6 +100,11 @@ static inline pte_t *hugepte_offset(hugepd_t hpd, unsigned long addr,
 	return hugepd_page(hpd) + idx;
 }
 
+static inline void hugepd_populate(hugepd_t *hpdp, pte_t *new, unsigned int pshift)
+{
+	*hpdp = __hugepd(__pa(new) | HUGEPD_VAL_BITS | (shift_to_mmu_psize(pshift) << 2));
+}
+
 void flush_hugetlb_page(struct vm_area_struct *vma, unsigned long vmaddr);
 
 #endif

arch/powerpc/include/asm/nohash/32/hugetlb-8xx.h

@@ -2,6 +2,8 @@
 #ifndef _ASM_POWERPC_NOHASH_32_HUGETLB_8XX_H
 #define _ASM_POWERPC_NOHASH_32_HUGETLB_8XX_H
 
+#define PAGE_SHIFT_8M		23
+
 static inline pte_t *hugepd_page(hugepd_t hpd)
 {
 	BUG_ON(!hugepd_ok(hpd));
@@ -28,4 +30,10 @@ static inline void flush_hugetlb_page(struct vm_area_struct *vma,
 	flush_tlb_page(vma, vmaddr);
 }
 
+static inline void hugepd_populate(hugepd_t *hpdp, pte_t *new, unsigned int pshift)
+{
+	*hpdp = __hugepd(__pa(new) | _PMD_USER | _PMD_PRESENT |
+			 (pshift == PAGE_SHIFT_8M ? _PMD_PAGE_8M : _PMD_PAGE_512K));
+}
+
 #endif /* _ASM_POWERPC_NOHASH_32_HUGETLB_8XX_H */

arch/powerpc/include/asm/nohash/hugetlb-book3e.h

@@ -28,4 +28,10 @@ static inline pte_t *hugepte_offset(hugepd_t hpd, unsigned long addr,
 
 void flush_hugetlb_page(struct vm_area_struct *vma, unsigned long vmaddr);
 
+static inline void hugepd_populate(hugepd_t *hpdp, pte_t *new, unsigned int pshift)
+{
+	/* We use the old format for PPC_FSL_BOOK3E */
+	*hpdp = __hugepd(((unsigned long)new & ~PD_HUGE) | pshift);
+}
+
 #endif /* _ASM_POWERPC_NOHASH_HUGETLB_BOOK3E_H */

arch/powerpc/mm/hugetlbpage.c

@@ -26,12 +26,6 @@
 #include <asm/hugetlb.h>
 #include <asm/pte-walk.h>
 
-#define PAGE_SHIFT_64K	16
-#define PAGE_SHIFT_512K	19
-#define PAGE_SHIFT_8M	23
-#define PAGE_SHIFT_16M	24
-#define PAGE_SHIFT_16G	34
-
 bool hugetlb_disabled = false;
 
 unsigned int HPAGE_SHIFT;
@@ -95,19 +89,7 @@ static int __hugepte_alloc(struct mm_struct *mm, hugepd_t *hpdp,
 	for (i = 0; i < num_hugepd; i++, hpdp++) {
 		if (unlikely(!hugepd_none(*hpdp)))
 			break;
-		else {
-#ifdef CONFIG_PPC_BOOK3S_64
-			*hpdp = __hugepd(__pa(new) | HUGEPD_VAL_BITS |
-					 (shift_to_mmu_psize(pshift) << 2));
-#elif defined(CONFIG_PPC_8xx)
-			*hpdp = __hugepd(__pa(new) | _PMD_USER |
-					 (pshift == PAGE_SHIFT_8M ? _PMD_PAGE_8M :
-					  _PMD_PAGE_512K) | _PMD_PRESENT);
-#else
-			/* We use the old format for PPC_FSL_BOOK3E */
-			*hpdp = __hugepd(((unsigned long)new & ~PD_HUGE) | pshift);
-#endif
-		}
+		hugepd_populate(hpdp, new, pshift);
 	}
 	/* If we bailed from the for loop early, an error occurred, clean up */
 	if (i < num_hugepd) {