[Suspend2][ 21/28] [Suspend2] Get swapwriter image storage needed.

[Nigel Cunningham <nigel@suspend2.net>]

Return the amount of space in the image header needed for swapwriter
configuration info.

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

 kernel/power/suspend_swap.c |   25 +++++++++++++++++++++++++
 1 files changed, 25 insertions(+), 0 deletions(-)

diff --git a/kernel/power/suspend_swap.c b/kernel/power/suspend_swap.c
index 3589b63..ba6ed75 100644
--- a/kernel/power/suspend_swap.c
+++ b/kernel/power/suspend_swap.c
@@ -847,3 +847,28 @@ static int swapwriter_print_debug_stats(
 	return len;
 }
 
+/*
+ * Storage needed
+ *
+ * Returns amount of space in the swap header required
+ * for the swapwriter's data. This ignores the links between
+ * pages, which we factor in when allocating the space.
+ *
+ * We ensure the space is allocated, but actually save the
+ * data from write_header_init and therefore don't also define a
+ * save_config_info routine.
+ */
+static unsigned long swapwriter_storage_needed(void)
+{
+	int i, result;
+	result = sizeof(suspend_writer_posn_save) + sizeof(devinfo);
+
+	for (i = 0; i < MAX_SWAPFILES; i++) {
+		result += 3 * sizeof(int);
+		result += (2 * sizeof(unsigned long) * 
+			(block_chain[i].allocs - block_chain[i].frees));
+	}
+
+	return result;
+}
+

--
Nigel Cunningham		nigel at suspend2 dot net