mmu_notifier: Callbacks for xip_filemap.c

Do the same trick that we use for do_wp_page(): Call invalidate_range_start/end
on a single page.

Signed-off-by: Robin Holt <holt@sgi.com>
Signed-off-by: Christoph Lameter <clameter@sgi.com>

---
 mm/filemap_xip.c |    7 +++++++
 1 file changed, 7 insertions(+)

Index: linux-2.6/mm/filemap_xip.c
===================================================================
--- linux-2.6.orig/mm/filemap_xip.c	2008-01-30 19:35:52.000000000 -0800
+++ linux-2.6/mm/filemap_xip.c	2008-01-30 19:36:17.000000000 -0800
@@ -13,6 +13,7 @@
 #include <linux/module.h>
 #include <linux/uio.h>
 #include <linux/rmap.h>
+#include <linux/mmu_notifier.h>
 #include <linux/sched.h>
 #include <asm/tlbflush.h>
 
@@ -183,12 +184,17 @@ __xip_unmap (struct address_space * mapp
 	if (!page)
 		return;
 
+	if (PageExternalRmap(page))
+		mmu_rmap_notifier(invalidate_page, page);
+
 	spin_lock(&mapping->i_mmap_lock);
 	vma_prio_tree_foreach(vma, &iter, &mapping->i_mmap, pgoff, pgoff) {
 		mm = vma->vm_mm;
 		address = vma->vm_start +
 			((pgoff - vma->vm_pgoff) << PAGE_SHIFT);
 		BUG_ON(address < vma->vm_start || address >= vma->vm_end);
+		mmu_notifier(invalidate_range_start, mm, address,
+					address + PAGE_SIZE - 1, 1);
 		pte = page_check_address(page, mm, address, &ptl);
 		if (pte) {
 			/* Nuke the page table entry. */
@@ -200,6 +206,7 @@ __xip_unmap (struct address_space * mapp
 			pte_unmap_unlock(pte, ptl);
 			page_cache_release(page);
 		}
+		mmu_notifier(invalidate_range_end, mm);
 	}
 	spin_unlock(&mapping->i_mmap_lock);
 }