From 0ca1634d4143c3579273ca53b993df19f5c98e92 Mon Sep 17 00:00:00 2001 From: Johannes Weiner Date: Thu, 13 Jan 2011 15:47:02 -0800 Subject: thp: mincore transparent hugepage support Handle transparent huge page pmd entries natively instead of splitting them into subpages. Signed-off-by: Johannes Weiner Signed-off-by: Andrea Arcangeli Reviewed-by: Rik van Riel Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/huge_memory.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) (limited to 'mm/huge_memory.c') diff --git a/mm/huge_memory.c b/mm/huge_memory.c index ae2bf08b1099..37e89a32a0b1 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -923,6 +923,31 @@ int zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma, return ret; } +int mincore_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, + unsigned long addr, unsigned long end, + unsigned char *vec) +{ + int ret = 0; + + spin_lock(&vma->vm_mm->page_table_lock); + if (likely(pmd_trans_huge(*pmd))) { + ret = !pmd_trans_splitting(*pmd); + spin_unlock(&vma->vm_mm->page_table_lock); + if (unlikely(!ret)) + wait_split_huge_page(vma->anon_vma, pmd); + else { + /* + * All logical pages in the range are present + * if backed by a huge page. + */ + memset(vec, 1, (end - addr) >> PAGE_SHIFT); + } + } else + spin_unlock(&vma->vm_mm->page_table_lock); + + return ret; +} + pmd_t *page_check_address_pmd(struct page *page, struct mm_struct *mm, unsigned long address, -- cgit v1.2.3