Merge branch 'linux-2.6' into for-2.6.22

1 files changed, 28 insertions, 0 deletions

diff --git a/mm/nommu.c b/mm/nommu.c
index 23fb033e596d..cbbc13774819 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -826,6 +826,11 @@ unsigned long do_mmap_pgoff(struct file *file,
 		unsigned long pglen = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
 		unsigned long vmpglen;
 
+		/* suppress VMA sharing for shared regions */
+		if (vm_flags & VM_SHARED &&
+		    capabilities & BDI_CAP_MAP_DIRECT)
+			goto dont_share_VMAs;
+
 		for (rb = rb_first(&nommu_vma_tree); rb; rb = rb_next(rb)) {
 			vma = rb_entry(rb, struct vm_area_struct, vm_rb);
 
@@ -859,6 +864,7 @@ unsigned long do_mmap_pgoff(struct file *file,
 			goto shared;
 		}
 
+	dont_share_VMAs:
 		vma = NULL;
 
 		/* obtain the address at which to make a shared mapping
@@ -1193,6 +1199,28 @@ void unmap_mapping_range(struct address_space *mapping,
 EXPORT_SYMBOL(unmap_mapping_range);
 
 /*
+ * ask for an unmapped area at which to create a mapping on a file
+ */
+unsigned long get_unmapped_area(struct file *file, unsigned long addr,
+				unsigned long len, unsigned long pgoff,
+				unsigned long flags)
+{
+	unsigned long (*get_area)(struct file *, unsigned long, unsigned long,
+				  unsigned long, unsigned long);
+
+	get_area = current->mm->get_unmapped_area;
+	if (file && file->f_op && file->f_op->get_unmapped_area)
+		get_area = file->f_op->get_unmapped_area;
+
+	if (!get_area)
+		return -ENOSYS;
+
+	return get_area(file, addr, len, pgoff, flags);
+}
+
+EXPORT_SYMBOL(get_unmapped_area);
+
+/*
  * Check that a process has enough memory to allocate a new virtual
  * mapping. 0 means there is enough memory for the allocation to
  * succeed and -ENOMEM implies there is not.