1 files changed, 20 insertions, 28 deletions

diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index 5e03b2f67b9..7f4756963d0 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -62,24 +62,19 @@ static int hugetlbfs_file_mmap(struct file *file, struct vm_area_struct *vma)
 	loff_t len, vma_len;
 	int ret;
 
-	if (vma->vm_pgoff & (HPAGE_SIZE / PAGE_SIZE - 1))
-		return -EINVAL;
-
-	if (vma->vm_start & ~HPAGE_MASK)
-		return -EINVAL;
-
-	if (vma->vm_end & ~HPAGE_MASK)
-		return -EINVAL;
-
-	if (vma->vm_end - vma->vm_start < HPAGE_SIZE)
-		return -EINVAL;
+	/*
+	 * vma alignment has already been checked by prepare_hugepage_range.
+	 * If you add any error returns here, do so after setting VM_HUGETLB,
+	 * so is_vm_hugetlb_page tests below unmap_region go the right way
+	 * when do_mmap_pgoff unwinds (may be important on powerpc and ia64).
+	 */
+	vma->vm_flags |= VM_HUGETLB | VM_RESERVED;
+	vma->vm_ops = &hugetlb_vm_ops;
 
 	vma_len = (loff_t)(vma->vm_end - vma->vm_start);
 
 	mutex_lock(&inode->i_mutex);
 	file_accessed(file);
-	vma->vm_flags |= VM_HUGETLB | VM_RESERVED;
-	vma->vm_ops = &hugetlb_vm_ops;
 
 	ret = -ENOMEM;
 	len = vma_len + ((loff_t)vma->vm_pgoff << PAGE_SHIFT);
@@ -271,29 +266,27 @@ static void hugetlbfs_drop_inode(struct inode *inode)
 		hugetlbfs_forget_inode(inode);
 }
 
-/*
- * h_pgoff is in HPAGE_SIZE units.
- * vma->vm_pgoff is in PAGE_SIZE units.
- */
 static inline void
-hugetlb_vmtruncate_list(struct prio_tree_root *root, unsigned long h_pgoff)
+hugetlb_vmtruncate_list(struct prio_tree_root *root, pgoff_t pgoff)
 {
 	struct vm_area_struct *vma;
 	struct prio_tree_iter iter;
 
-	vma_prio_tree_foreach(vma, &iter, root, h_pgoff, ULONG_MAX) {
-		unsigned long h_vm_pgoff;
+	vma_prio_tree_foreach(vma, &iter, root, pgoff, ULONG_MAX) {
 		unsigned long v_offset;
 
-		h_vm_pgoff = vma->vm_pgoff >> (HPAGE_SHIFT - PAGE_SHIFT);
-		v_offset = (h_pgoff - h_vm_pgoff) << HPAGE_SHIFT;
 		/*
-		 * Is this VMA fully outside the truncation point?
+		 * Can the expression below overflow on 32-bit arches?
+		 * No, because the prio_tree returns us only those vmas
+		 * which overlap the truncated area starting at pgoff,
+		 * and no vma on a 32-bit arch can span beyond the 4GB.
 		 */
-		if (h_vm_pgoff >= h_pgoff)
+		if (vma->vm_pgoff < pgoff)
+			v_offset = (pgoff - vma->vm_pgoff) << PAGE_SHIFT;
+		else
 			v_offset = 0;
 
-		unmap_hugepage_range(vma,
+		__unmap_hugepage_range(vma,
 				vma->vm_start + v_offset, vma->vm_end);
 	}
 }
@@ -303,14 +296,14 @@ hugetlb_vmtruncate_list(struct prio_tree_root *root, unsigned long h_pgoff)
  */
 static int hugetlb_vmtruncate(struct inode *inode, loff_t offset)
 {
-	unsigned long pgoff;
+	pgoff_t pgoff;
 	struct address_space *mapping = inode->i_mapping;
 
 	if (offset > inode->i_size)
 		return -EINVAL;
 
 	BUG_ON(offset & ~HPAGE_MASK);
-	pgoff = offset >> HPAGE_SHIFT;
+	pgoff = offset >> PAGE_SHIFT;
 
 	inode->i_size = offset;
 	spin_lock(&mapping->i_mmap_lock);
@@ -624,7 +617,6 @@ hugetlbfs_parse_options(char *options, struct hugetlbfs_config *pconfig)
 				do_div(size, 100);
 				rest++;
 			}
-			size &= HPAGE_MASK;
 			pconfig->nr_blocks = (size >> HPAGE_SHIFT);
 			value = rest;
 		} else if (!strcmp(opt,"nr_inodes")) {