follow: Do not put_page() if no flags are specified.

Seems that one of the side effects of the dirty pages patch in
2.6.17-rc4-mm3 is that follow_pages does a page_put if flags = 0.
This breaks the new sys_move_pages().

Only put_page if we did a get_page() before.

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

Index: linux-2.6.17-rc4-mm3/mm/migrate.c
===================================================================
--- linux-2.6.17-rc4-mm3.orig/mm/migrate.c	2006-05-23 17:27:20.617652640 -0700
+++ linux-2.6.17-rc4-mm3/mm/migrate.c	2006-05-23 17:57:02.747364602 -0700
@@ -592,8 +592,10 @@ static int unmap_and_move(new_page_t get
 	int *result = NULL;
 	struct page *newpage = get_new_page(page, private, &result);
 
-	if (!newpage)
+	if (!newpage) {
+		printk(KERN_CRIT "unmap_and_move: get_new_page(%p,%lu %p) returned NULL\n",page, private, result);
 		return -ENOMEM;
+	}
 
 	if (page_count(page) == 1)
 		/* page was freed from under us. So we are done. */
@@ -679,6 +681,7 @@ int migrate_pages(struct list_head *from
 	if (!swapwrite)
 		current->flags |= PF_SWAPWRITE;
 
+	printk(KERN_CRIT "migrate_pages(%p,%p,%lu)\n",from,get_new_page,private);
 	for(pass = 0; pass < 10 && retry; pass++) {
 		retry = 0;
 
Index: linux-2.6.17-rc4-mm3/mm/mempolicy.c
===================================================================
--- linux-2.6.17-rc4-mm3.orig/mm/mempolicy.c	2006-05-23 15:10:24.459969091 -0700
+++ linux-2.6.17-rc4-mm3/mm/mempolicy.c	2006-05-23 17:57:02.748341104 -0700
@@ -1846,6 +1846,9 @@ int show_numa_map(struct seq_file *m, vo
 				&node_online_map, MPOL_MF_STATS, md);
 	}
 
+	if (vma->vm_flags & VM_LOCKED)
+		seq_printf(m, " locked");
+
 	if (!md->pages)
 		goto out;