MIPS: Add support files for hugetlbfs.

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

2 files changed, 102 insertions, 0 deletions

diff --git a/arch/mips/mm/Makefile b/arch/mips/mm/Makefile
index d7ec95522292..f0e435599707 100644
--- a/arch/mips/mm/Makefile
+++ b/arch/mips/mm/Makefile
@@ -8,6 +8,7 @@ obj-y				+= cache.o dma-default.o extable.o fault.o \
 obj-$(CONFIG_32BIT)             += ioremap.o pgtable-32.o
 obj-$(CONFIG_64BIT)             += pgtable-64.o
 obj-$(CONFIG_HIGHMEM)           += highmem.o
+obj-$(CONFIG_HUGETLB_PAGE)      += hugetlbpage.o
 
 obj-$(CONFIG_CPU_LOONGSON2)     += c-r4k.o cex-gen.o tlb-r4k.o
 obj-$(CONFIG_CPU_MIPS32)        += c-r4k.o cex-gen.o tlb-r4k.o
diff --git a/arch/mips/mm/hugetlbpage.c b/arch/mips/mm/hugetlbpage.c
new file mode 100644
index 000000000000..471c09aa1614
--- /dev/null
+++ b/arch/mips/mm/hugetlbpage.c
@@ -0,0 +1,101 @@
+/*
+ * MIPS Huge TLB Page Support for Kernel.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2002, Rohit Seth <rohit.seth@intel.com>
+ * Copyright 2005, Embedded Alley Solutions, Inc.
+ * Matt Porter <mporter@embeddedalley.com>
+ * Copyright (C) 2008, 2009 Cavium Networks, Inc.
+ */
+
+#include <linux/init.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/hugetlb.h>
+#include <linux/pagemap.h>
+#include <linux/smp_lock.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/sysctl.h>
+#include <asm/mman.h>
+#include <asm/tlb.h>
+#include <asm/tlbflush.h>
+
+pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr,
+                      unsigned long sz)
+{
+        pgd_t *pgd;
+        pud_t *pud;
+        pte_t *pte = NULL;
+
+        pgd = pgd_offset(mm, addr);
+        pud = pud_alloc(mm, pgd, addr);
+        if (pud)
+                pte = (pte_t *)pmd_alloc(mm, pud, addr);
+
+        return pte;
+}
+
+pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
+{
+        pgd_t *pgd;
+        pud_t *pud;
+        pmd_t *pmd = NULL;
+
+        pgd = pgd_offset(mm, addr);
+        if (pgd_present(*pgd)) {
+                pud = pud_offset(pgd, addr);
+                if (pud_present(*pud))
+                        pmd = pmd_offset(pud, addr);
+        }
+        return (pte_t *) pmd;
+}
+
+int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
+{
+        return 0;
+}
+
+/*
+ * This function checks for proper alignment of input addr and len parameters.
+ */
+int is_aligned_hugepage_range(unsigned long addr, unsigned long len)
+{
+        if (len & ~HPAGE_MASK)
+                return -EINVAL;
+        if (addr & ~HPAGE_MASK)
+                return -EINVAL;
+        return 0;
+}
+
+struct page *
+follow_huge_addr(struct mm_struct *mm, unsigned long address, int write)
+{
+        return ERR_PTR(-EINVAL);
+}
+
+int pmd_huge(pmd_t pmd)
+{
+        return (pmd_val(pmd) & _PAGE_HUGE) != 0;
+}
+
+int pud_huge(pud_t pud)
+{
+        return (pud_val(pud) & _PAGE_HUGE) != 0;
+}
+
+struct page *
+follow_huge_pmd(struct mm_struct *mm, unsigned long address,
+                pmd_t *pmd, int write)
+{
+        struct page *page;
+
+        page = pte_page(*(pte_t *)pmd);
+        if (page)
+                page += ((address & ~HPAGE_MASK) >> PAGE_SHIFT);
+        return page;
+}
+