sh: hugetlb updates.

For some of the larger sizes we permitted spanning pages
across several PTEs, but this turned out to not be generally
useful. This reverts the sh hugetlbpage interface to something
more sensible using huge pages at single PTE granularity.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

arch/sh/mm/hugetlbpage.c

@@ -26,61 +26,41 @@
 pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr)
 {
 	pgd_t *pgd;
+	pud_t *pud;
 	pmd_t *pmd;
 	pte_t *pte = NULL;
 
 	pgd = pgd_offset(mm, addr);
 	if (pgd) {
-		pmd = pmd_alloc(mm, pgd, addr);
+		pud = pud_alloc(mm, pgd, addr);
+		if (pud) {
+			pmd = pmd_alloc(mm, pud, addr);
 			if (pmd)
 				pte = pte_alloc_map(mm, pmd, addr);
 		}
+	}
+
 	return pte;
 }
 
 pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
 {
 	pgd_t *pgd;
+	pud_t *pud;
 	pmd_t *pmd;
 	pte_t *pte = NULL;
 
 	pgd = pgd_offset(mm, addr);
 	if (pgd) {
-		pmd = pmd_offset(pgd, addr);
+		pud = pud_offset(pgd, addr);
+		if (pud) {
+			pmd = pmd_offset(pud, addr);
 			if (pmd)
 				pte = pte_offset_map(pmd, addr);
 		}
-	return pte;
-}
-
-void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
-		     pte_t *ptep, pte_t entry)
-{
-	int i;
-
-	for (i = 0; i < (1 << HUGETLB_PAGE_ORDER); i++) {
-		set_pte_at(mm, addr, ptep, entry);
-		ptep++;
-		addr += PAGE_SIZE;
-		pte_val(entry) += PAGE_SIZE;
-	}
-}
-
-pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
-			      pte_t *ptep)
-{
-	pte_t entry;
-	int i;
-
-	entry = *ptep;
-
-	for (i = 0; i < (1 << HUGETLB_PAGE_ORDER); i++) {
-		pte_clear(mm, addr, ptep);
-		addr += PAGE_SIZE;
-		ptep++;
 	}
 
-	return entry;
+	return pte;
 }
 
 struct page *follow_huge_addr(struct mm_struct *mm,

include/asm-sh/page.h

@@ -30,7 +30,6 @@
 #define HPAGE_SIZE		(1UL << HPAGE_SHIFT)
 #define HPAGE_MASK		(~(HPAGE_SIZE-1))
 #define HUGETLB_PAGE_ORDER	(HPAGE_SHIFT-PAGE_SHIFT)
-#define ARCH_HAS_SETCLEAR_HUGE_PTE
 #endif
 
 #ifdef __KERNEL__