+static void calc_sectors(struct r10conf *conf, sector_t size)
+{
+ /* Calculate the number of sectors-per-device that will
+ * actually be used, and set conf->dev_sectors and
+ * conf->stride
+ */
+
+ size = size >> conf->chunk_shift;
+ sector_div(size, conf->far_copies);
+ size = size * conf->raid_disks;
+ sector_div(size, conf->near_copies);
+ /* 'size' is now the number of chunks in the array */
+ /* calculate "used chunks per device" */
+ size = size * conf->copies;
+
+ /* We need to round up when dividing by raid_disks to
+ * get the stride size.
+ */
+ size = DIV_ROUND_UP_SECTOR_T(size, conf->raid_disks);
+
+ conf->dev_sectors = size << conf->chunk_shift;
+
+ if (conf->far_offset)
+ conf->stride = 1 << conf->chunk_shift;
+ else {
+ sector_div(size, conf->near_copies);
+ conf->stride = size << conf->chunk_shift;
+ }
+}