[PATCH] NOMMU: supply get_unmapped_area() to fix NOMMU SYSV SHM
David Howells [Thu, 22 Mar 2007 08:11:23 +0000 (00:11 -0800)]
Supply a get_unmapped_area() to fix NOMMU SYSV SHM support.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Adam Litke <agl@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/nommu.c

index 23fb033..ba6df4d 100644 (file)
@@ -1193,6 +1193,28 @@ 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.