[PATCH] hugetlb: fix error return for brk() entering a hugepage region

[pandora-kernel.git] / mm / hugetlb.c

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 7c7d03d..a088f59 100644 (file)
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -356,14 +356,16 @@ nomem:
        return -ENOMEM;
 }
 
-void unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start,
-                         unsigned long end)
+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 *ptep;
        pte_t pte;
        struct page *page;
+       struct page *tmp;
+       LIST_HEAD(page_list);
 
        WARN_ON(!is_vm_hugetlb_page(vma));
        BUG_ON(start & ~HPAGE_MASK);
@@ -384,12 +386,34 @@ void unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start,
                        continue;
 
                page = pte_page(pte);
-               put_page(page);
+               list_add(&page->lru, &page_list);
                add_mm_counter(mm, file_rss, (int) -(HPAGE_SIZE / PAGE_SIZE));
        }
 
        spin_unlock(&mm->page_table_lock);
        flush_tlb_range(vma, start, end);
+       list_for_each_entry_safe(page, tmp, &page_list, lru) {
+               list_del(&page->lru);
+               put_page(page);
+       }
+}
+
+void unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start,
+                         unsigned long end)
+{
+       /*
+        * It is undesirable to test vma->vm_file as it should be non-null
+        * for valid hugetlb area. However, vm_file will be NULL in the error
+        * cleanup path of do_mmap_pgoff. When hugetlbfs ->mmap method fails,
+        * do_mmap_pgoff() nullifies vma->vm_file before calling this function
+        * to clean up. Since no pte has actually been setup, it is safe to
+        * do nothing in this case.
+        */
+       if (vma->vm_file) {
+               spin_lock(&vma->vm_file->f_mapping->i_mmap_lock);
+               __unmap_hugepage_range(vma, start, end);
+               spin_unlock(&vma->vm_file->f_mapping->i_mmap_lock);
+       }
 }
 
 static int hugetlb_cow(struct mm_struct *mm, struct vm_area_struct *vma,
@@ -454,6 +478,9 @@ int hugetlb_no_page(struct mm_struct *mm, struct vm_area_struct *vma,
 retry:
        page = find_lock_page(mapping, idx);
        if (!page) {
+               size = i_size_read(mapping->host) >> HPAGE_SHIFT;
+               if (idx >= size)
+                       goto out;
                if (hugetlb_get_quota(mapping))
                        goto out;
                page = alloc_huge_page(vma, address);