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Diffstat (limited to 'arch/sh/mm/hugetlbpage.c')
-rw-r--r--arch/sh/mm/hugetlbpage.c264
1 files changed, 264 insertions, 0 deletions
diff --git a/arch/sh/mm/hugetlbpage.c b/arch/sh/mm/hugetlbpage.c
new file mode 100644
index 00000000000..1f897bab231
--- /dev/null
+++ b/arch/sh/mm/hugetlbpage.c
@@ -0,0 +1,264 @@
+/*
+ * arch/sh/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;
+}