[Suspend2][ 14/35] [Suspend2] Allocate filewriter header storage

[Nigel Cunningham <nigel@suspend2.net>]

Having already allocated storage, set aside a number of pages at the start
of the image for the header and record where pageset2 will start.

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

 kernel/power/suspend_file.c |   21 +++++++++++++++++++++
 1 files changed, 21 insertions(+), 0 deletions(-)

diff --git a/kernel/power/suspend_file.c b/kernel/power/suspend_file.c
index 257acca..6b04eb5 100644
--- a/kernel/power/suspend_file.c
+++ b/kernel/power/suspend_file.c
@@ -427,3 +427,24 @@ static int filewriter_release_storage(vo
 	return 0;
 }
 
+static int filewriter_allocate_header_space(int space_requested)
+{
+	int i;
+
+	if (!block_chain.first)
+		return 0;
+
+	suspend_extent_state_goto_start(&suspend_writer_posn);
+	suspend_bio_ops.forward_one_page(); /* To first page */
+	
+	for (i = 0; i < space_requested; i++)
+		if (suspend_bio_ops.forward_one_page())
+			return -ENOSPC;
+
+	/* The end of header pages will be the start of pageset 2 */
+	suspend_extent_state_save(&suspend_writer_posn,
+			&suspend_writer_posn_save[2]);
+	header_pages = space_requested;
+	return 0;
+}
+

--
Nigel Cunningham		nigel at suspend2 dot net