sparc64: Multi-page size support

Add support for using multiple hugepage sizes simultaneously
on mainline. Currently, support for 256M has been added which
can be used along with 8M pages.

Page tables are set like this (e.g. for 256M page):
    VA + (8M * x) -> PA + (8M * x) (sz bit = 256M) where x in [0, 31]

and TSB is set similarly:
    VA + (4M * x) -> PA + (4M * x) (sz bit = 256M) where x in [0, 63]

- Testing

Tested on Sonoma (which supports 256M pages) by running stream
benchmark instances in parallel: one instance uses 8M pages and
another uses 256M pages, consuming 48G each.

Boot params used:

default_hugepagesz=256M hugepagesz=256M hugepages=300 hugepagesz=8M
hugepages=10000

Signed-off-by: Nitin Gupta <nitin.m.gupta@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 15 insertions, 8 deletions

diff --git a/arch/sparc/include/asm/pgtable_64.h b/arch/sparc/include/asm/pgtable_64.h
index 314b668..7932a4a 100644
--- a/arch/sparc/include/asm/pgtable_64.h
+++ b/arch/sparc/include/asm/pgtable_64.h
@@ -375,7 +375,10 @@ static inline pgprot_t pgprot_noncached(pgprot_t prot)
 #define pgprot_noncached pgprot_noncached
 
 #if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE)
-static inline unsigned long __pte_huge_mask(void)
+extern pte_t arch_make_huge_pte(pte_t entry, struct vm_area_struct *vma,
+				struct page *page, int writable);
+#define arch_make_huge_pte arch_make_huge_pte
+static inline unsigned long __pte_default_huge_mask(void)
 {
 	unsigned long mask;
 
@@ -395,12 +398,14 @@ static inline unsigned long __pte_huge_mask(void)
 
 static inline pte_t pte_mkhuge(pte_t pte)
 {
-	return __pte(pte_val(pte) | _PAGE_PMD_HUGE | __pte_huge_mask());
+	return __pte(pte_val(pte) | __pte_default_huge_mask());
 }
 
-static inline bool is_hugetlb_pte(pte_t pte)
+static inline bool is_default_hugetlb_pte(pte_t pte)
 {
-	return !!(pte_val(pte) & __pte_huge_mask());
+	unsigned long mask = __pte_default_huge_mask();
+
+	return (pte_val(pte) & mask) == mask;
 }
 
 static inline bool is_hugetlb_pmd(pmd_t pmd)
@@ -875,10 +880,12 @@ static inline unsigned long pud_pfn(pud_t pud)
 
 /* Actual page table PTE updates.  */
 void tlb_batch_add(struct mm_struct *mm, unsigned long vaddr,
-		   pte_t *ptep, pte_t orig, int fullmm);
+		   pte_t *ptep, pte_t orig, int fullmm,
+		   unsigned int hugepage_shift);
 
 static void maybe_tlb_batch_add(struct mm_struct *mm, unsigned long vaddr,
-				pte_t *ptep, pte_t orig, int fullmm)
+				pte_t *ptep, pte_t orig, int fullmm,
+				unsigned int hugepage_shift)
 {
 	/* It is more efficient to let flush_tlb_kernel_range()
 	 * handle init_mm tlb flushes.
@@ -887,7 +894,7 @@ static void maybe_tlb_batch_add(struct mm_struct *mm, unsigned long vaddr,
 	 *             and SUN4V pte layout, so this inline test is fine.
 	 */
 	if (likely(mm != &init_mm) && pte_accessible(mm, orig))
-		tlb_batch_add(mm, vaddr, ptep, orig, fullmm);
+		tlb_batch_add(mm, vaddr, ptep, orig, fullmm, hugepage_shift);
 }
 
 #define __HAVE_ARCH_PMDP_HUGE_GET_AND_CLEAR
@@ -906,7 +913,7 @@ static inline void __set_pte_at(struct mm_struct *mm, unsigned long addr,
 	pte_t orig = *ptep;
 
 	*ptep = pte;
-	maybe_tlb_batch_add(mm, addr, ptep, orig, fullmm);
+	maybe_tlb_batch_add(mm, addr, ptep, orig, fullmm, PAGE_SHIFT);
 }
 
 #define set_pte_at(mm,addr,ptep,pte)	\