[Suspend2][ 6/9] [Suspend2] Get nonconflicting page.

[Nigel Cunningham <nigel@suspend2.net>]

In preparation for the atomic restore, get a page that can safely be used
during the restore - ie, that isn't a location of a page that will be
restored.

Signed-off-by: Nigel Cunningham <nigel@suspend2.net>

 kernel/power/pagedir.c |   18 ++++++++++++++++++
 1 files changed, 18 insertions(+), 0 deletions(-)

diff --git a/kernel/power/pagedir.c b/kernel/power/pagedir.c
index c23ca58..4cdc0ef 100644
--- a/kernel/power/pagedir.c
+++ b/kernel/power/pagedir.c
@@ -270,3 +270,21 @@ void suspend_mark_pages_for_pageset2(voi
 
 }
 
+/* suspend_get_nonconflicting_page
+ *
+ * Description: Gets order zero pages that won't be overwritten
+ *		while copying the original pages.
+ */
+
+unsigned long suspend_get_nonconflicting_page(void)
+{
+	struct page *page;
+
+	do {
+		page = alloc_pages(GFP_ATOMIC | __GFP_NOWARN | __GFP_ZERO, 0);
+		BUG_ON(!page);
+	} while(PagePageset1(page));
+
+	return (unsigned long) page_address(page);
+}
+

--
Nigel Cunningham		nigel at suspend2 dot net