From cea10a19b7972a1954c4a2d05a7de8db48b444fb Mon Sep 17 00:00:00 2001 From: Michel Lespinasse Date: Fri, 22 Feb 2013 16:32:44 -0800 Subject: mm: directly use __mlock_vma_pages_range() in find_extend_vma() In find_extend_vma(), we don't need mlock_vma_pages_range() to verify the vma type - we know we're working with a stack. So, we can call directly into __mlock_vma_pages_range(), and remove the last make_pages_present() call site. Note that we don't use mm_populate() here, so we can't release the mmap_sem while allocating new stack pages. This is deemed acceptable, because the stack vmas grow by a bounded number of pages at a time, and these are anon pages so we don't have to read from disk to populate them. Signed-off-by: Michel Lespinasse Acked-by: Rik van Riel Tested-by: Andy Lutomirski Cc: Greg Ungerer Cc: David Howells Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/memory.c | 24 ------------------------ 1 file changed, 24 deletions(-) (limited to 'mm/memory.c') diff --git a/mm/memory.c b/mm/memory.c index 0abd07097ec6..7837ceacf090 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -3824,30 +3824,6 @@ int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address) } #endif /* __PAGETABLE_PMD_FOLDED */ -int make_pages_present(unsigned long addr, unsigned long end) -{ - int ret, len, write; - struct vm_area_struct * vma; - - vma = find_vma(current->mm, addr); - if (!vma) - return -ENOMEM; - /* - * We want to touch writable mappings with a write fault in order - * to break COW, except for shared mappings because these don't COW - * and we would not want to dirty them for nothing. - */ - write = (vma->vm_flags & (VM_WRITE | VM_SHARED)) == VM_WRITE; - BUG_ON(addr >= end); - BUG_ON(end > vma->vm_end); - len = DIV_ROUND_UP(end, PAGE_SIZE) - addr/PAGE_SIZE; - ret = get_user_pages(current, current->mm, addr, - len, write, 0, NULL, NULL); - if (ret < 0) - return ret; - return ret == len ? 0 : -EFAULT; -} - #if !defined(__HAVE_ARCH_GATE_AREA) #if defined(AT_SYSINFO_EHDR) -- cgit v1.2.3