libceph: introduce apply_temps() helper
apply_temp() helper for applying various temporary mappings (at this
point only pg_temp mappings) to the up set, therefore transforming it
into an acting set.
Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
Reviewed-by: Alex Elder <elder@linaro.org>
diff --git a/net/ceph/osdmap.c b/net/ceph/osdmap.c
index b8bbef0..bd40f56 100644
--- a/net/ceph/osdmap.c
+++ b/net/ceph/osdmap.c
@@ -1597,6 +1597,58 @@
}
/*
+ * Given up set, apply pg_temp mapping.
+ *
+ * Return acting set length. *primary is set to acting primary osd id,
+ * or -1 if acting set is empty.
+ */
+static int apply_temps(struct ceph_osdmap *osdmap,
+ struct ceph_pg_pool_info *pool, struct ceph_pg pgid,
+ int *osds, int len, int *primary)
+{
+ struct ceph_pg_mapping *pg;
+ int temp_len;
+ int temp_primary;
+ int i;
+
+ /* raw_pg -> pg */
+ pgid.seed = ceph_stable_mod(pgid.seed, pool->pg_num,
+ pool->pg_num_mask);
+
+ /* pg_temp? */
+ pg = __lookup_pg_mapping(&osdmap->pg_temp, pgid);
+ if (pg) {
+ temp_len = 0;
+ temp_primary = -1;
+
+ for (i = 0; i < pg->pg_temp.len; i++) {
+ if (ceph_osd_is_down(osdmap, pg->pg_temp.osds[i])) {
+ if (ceph_can_shift_osds(pool))
+ continue;
+ else
+ osds[temp_len++] = CRUSH_ITEM_NONE;
+ } else {
+ osds[temp_len++] = pg->pg_temp.osds[i];
+ }
+ }
+
+ /* apply pg_temp's primary */
+ for (i = 0; i < temp_len; i++) {
+ if (osds[i] != CRUSH_ITEM_NONE) {
+ temp_primary = osds[i];
+ break;
+ }
+ }
+ } else {
+ temp_len = len;
+ temp_primary = *primary;
+ }
+
+ *primary = temp_primary;
+ return temp_len;
+}
+
+/*
* Return acting set for given pgid.
*/
int ceph_calc_pg_acting(struct ceph_osdmap *osdmap, struct ceph_pg pgid,