1 files changed, 264 insertions, 0 deletions

diff --git a/arch/sh64/mm/hugetlbpage.c b/arch/sh64/mm/hugetlbpage.c
new file mode 100644
index 000000000000..bcad2aefa4ee
--- /dev/null
+++ b/arch/sh64/mm/hugetlbpage.c
@@ -0,0 +1,264 @@
+/*
+ * arch/sh64/mm/hugetlbpage.c
+ *
+ * SuperH HugeTLB page support.
+ *
+ * Cloned from sparc64 by Paul Mundt.
+ *
+ * Copyright (C) 2002, 2003 David S. Miller (davem@redhat.com)
+ */
+
+#include <linux/config.h>
+#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/sysctl.h>
+
+#include <asm/mman.h>
+#include <asm/pgalloc.h>
+#include <asm/tlb.h>
+#include <asm/tlbflush.h>
+#include <asm/cacheflush.h>
+
+static pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr)
+{
+        pgd_t *pgd;
+        pmd_t *pmd;
+        pte_t *pte = NULL;
+
+        pgd = pgd_offset(mm, addr);
+        if (pgd) {
+                pmd = pmd_alloc(mm, pgd, addr);
+                if (pmd)
+                        pte = pte_alloc_map(mm, pmd, addr);
+        }
+        return pte;
+}
+
+static pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
+{
+        pgd_t *pgd;
+        pmd_t *pmd;
+        pte_t *pte = NULL;
+
+        pgd = pgd_offset(mm, addr);
+        if (pgd) {
+                pmd = pmd_offset(pgd, addr);
+                if (pmd)
+                        pte = pte_offset_map(pmd, addr);
+        }
+        return pte;
+}
+
+#define mk_pte_huge(entry) do { pte_val(entry) |= _PAGE_SZHUGE; } while (0)
+
+static void set_huge_pte(struct mm_struct *mm, struct vm_area_struct *vma,
+                         struct page *page, pte_t * page_table, int write_access)
+{
+        unsigned long i;
+        pte_t entry;
+
+        add_mm_counter(mm, rss, HPAGE_SIZE / PAGE_SIZE);
+
+        if (write_access)
+                entry = pte_mkwrite(pte_mkdirty(mk_pte(page,
+                                                       vma->vm_page_prot)));
+        else
+                entry = pte_wrprotect(mk_pte(page, vma->vm_page_prot));
+        entry = pte_mkyoung(entry);
+        mk_pte_huge(entry);
+
+        for (i = 0; i < (1 << HUGETLB_PAGE_ORDER); i++) {
+                set_pte(page_table, entry);
+                page_table++;
+
+                pte_val(entry) += PAGE_SIZE;
+        }
+}
+
+/*
+ * 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;
+}
+
+int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src,
+                            struct vm_area_struct *vma)
+{
+        pte_t *src_pte, *dst_pte, entry;
+        struct page *ptepage;
+        unsigned long addr = vma->vm_start;
+        unsigned long end = vma->vm_end;
+        int i;
+
+        while (addr < end) {
+                dst_pte = huge_pte_alloc(dst, addr);
+                if (!dst_pte)
+                        goto nomem;
+                src_pte = huge_pte_offset(src, addr);
+                BUG_ON(!src_pte || pte_none(*src_pte));
+                entry = *src_pte;
+                ptepage = pte_page(entry);
+                get_page(ptepage);
+                for (i = 0; i < (1 << HUGETLB_PAGE_ORDER); i++) {
+                        set_pte(dst_pte, entry);
+                        pte_val(entry) += PAGE_SIZE;
+                        dst_pte++;
+                }
+                add_mm_counter(dst, rss, HPAGE_SIZE / PAGE_SIZE);
+                addr += HPAGE_SIZE;
+        }
+        return 0;
+
+nomem:
+        return -ENOMEM;
+}
+
+int follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma,
+                        struct page **pages, struct vm_area_struct **vmas,
+                        unsigned long *position, int *length, int i)
+{
+        unsigned long vaddr = *position;
+        int remainder = *length;
+
+        WARN_ON(!is_vm_hugetlb_page(vma));
+
+        while (vaddr < vma->vm_end && remainder) {
+                if (pages) {
+                        pte_t *pte;
+                        struct page *page;
+
+                        pte = huge_pte_offset(mm, vaddr);
+
+                        /* hugetlb should be locked, and hence, prefaulted */
+                        BUG_ON(!pte || pte_none(*pte));
+
+                        page = pte_page(*pte);
+
+                        WARN_ON(!PageCompound(page));
+
+                        get_page(page);
+                        pages[i] = page;
+                }
+
+                if (vmas)
+                        vmas[i] = vma;
+
+                vaddr += PAGE_SIZE;
+                --remainder;
+                ++i;
+        }
+
+        *length = remainder;
+        *position = vaddr;
+
+        return i;
+}
+
+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 0;
+}
+
+struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address,
+                             pmd_t *pmd, int write)
+{
+        return NULL;
+}
+
+void unmap_hugepage_range(struct vm_area_struct *vma,
+                          unsigned long start, unsigned long end)
+{
+        struct mm_struct *mm = vma->vm_mm;
+        unsigned long address;
+        pte_t *pte;
+        struct page *page;
+        int i;
+
+        BUG_ON(start & (HPAGE_SIZE - 1));
+        BUG_ON(end & (HPAGE_SIZE - 1));
+
+        for (address = start; address < end; address += HPAGE_SIZE) {
+                pte = huge_pte_offset(mm, address);
+                BUG_ON(!pte);
+                if (pte_none(*pte))
+                        continue;
+                page = pte_page(*pte);
+                put_page(page);
+                for (i = 0; i < (1 << HUGETLB_PAGE_ORDER); i++) {
+                        pte_clear(mm, address+(i*PAGE_SIZE), pte);
+                        pte++;
+                }
+        }
+        add_mm_counter(mm, rss, -((end - start) >> PAGE_SHIFT));
+        flush_tlb_range(vma, start, end);
+}
+
+int hugetlb_prefault(struct address_space *mapping, struct vm_area_struct *vma)
+{
+        struct mm_struct *mm = current->mm;
+        unsigned long addr;
+        int ret = 0;
+
+        BUG_ON(vma->vm_start & ~HPAGE_MASK);
+        BUG_ON(vma->vm_end & ~HPAGE_MASK);
+
+        spin_lock(&mm->page_table_lock);
+        for (addr = vma->vm_start; addr < vma->vm_end; addr += HPAGE_SIZE) {
+                unsigned long idx;
+                pte_t *pte = huge_pte_alloc(mm, addr);
+                struct page *page;
+
+                if (!pte) {
+                        ret = -ENOMEM;
+                        goto out;
+                }
+                if (!pte_none(*pte))
+                        continue;
+
+                idx = ((addr - vma->vm_start) >> HPAGE_SHIFT)
+                        + (vma->vm_pgoff >> (HPAGE_SHIFT - PAGE_SHIFT));
+                page = find_get_page(mapping, idx);
+                if (!page) {
+                        /* charge the fs quota first */
+                        if (hugetlb_get_quota(mapping)) {
+                                ret = -ENOMEM;
+                                goto out;
+                        }
+                        page = alloc_huge_page();
+                        if (!page) {
+                                hugetlb_put_quota(mapping);
+                                ret = -ENOMEM;
+                                goto out;
+                        }
+                        ret = add_to_page_cache(page, mapping, idx, GFP_ATOMIC);
+                        if (! ret) {
+                                unlock_page(page);
+                        } else {
+                                hugetlb_put_quota(mapping);
+                                free_huge_page(page);
+                                goto out;
+                        }
+                }
+                set_huge_pte(mm, vma, page, pte, vma->vm_flags & VM_WRITE);
+        }
+out:
+        spin_unlock(&mm->page_table_lock);
+        return ret;
+}