libceph: rename ceph_oloc_oid_to_pg()

Rename ceph_oloc_oid_to_pg() to ceph_object_locator_to_pg().  Emphasise
that returned is raw PG and return -ENOENT instead of -EIO if the pool
doesn't exist.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

fs/ceph/ioctl.c

@@ -215,7 +215,7 @@ static long ceph_ioctl_get_dataloc(struct file *file, void __user *arg)
 	oloc.pool = ceph_file_layout_pg_pool(ci->i_layout);
 	ceph_oid_printf(&oid, "%s", dl.object_name);
 
-	r = ceph_oloc_oid_to_pg(osdc->osdmap, &oloc, &oid, &pgid);
+	r = ceph_object_locator_to_pg(osdc->osdmap, &oid, &oloc, &pgid);
 	if (r < 0) {
 		up_read(&osdc->map_sem);
 		return r;

include/linux/ceph/osdmap.h

@@ -213,11 +213,10 @@ extern int ceph_calc_file_object_mapping(struct ceph_file_layout *layout,
 					 u64 off, u64 len,
 					 u64 *bno, u64 *oxoff, u64 *oxlen);
 
-/* calculate mapping of object to a placement group */
-extern int ceph_oloc_oid_to_pg(struct ceph_osdmap *osdmap,
-			       struct ceph_object_locator *oloc,
+int ceph_object_locator_to_pg(struct ceph_osdmap *osdmap,
 			      struct ceph_object_id *oid,
-			       struct ceph_pg *pg_out);
+			      struct ceph_object_locator *oloc,
+			      struct ceph_pg *raw_pgid);
 
 extern int ceph_calc_pg_acting(struct ceph_osdmap *osdmap,
 			       struct ceph_pg pgid,

net/ceph/osd_client.c

@@ -1324,8 +1324,8 @@ static int __calc_request_pg(struct ceph_osdmap *osdmap,
 		/* !pi is caught in ceph_oloc_oid_to_pg() */
 	}
 
-	return ceph_oloc_oid_to_pg(osdmap, &req->r_target_oloc,
-				   &req->r_target_oid, pg_out);
+	return ceph_object_locator_to_pg(osdmap, &req->r_target_oid,
+					 &req->r_target_oloc, pg_out);
 }
 
 static void __enqueue_request(struct ceph_osd_request *req)

net/ceph/osdmap.c

@@ -1545,30 +1545,31 @@ int ceph_calc_file_object_mapping(struct ceph_file_layout *layout,
 EXPORT_SYMBOL(ceph_calc_file_object_mapping);
 
 /*
- * Calculate mapping of a (oloc, oid) pair to a PG.  Should only be
- * called with target's (oloc, oid), since tiering isn't taken into
- * account.
+ * Map an object into a PG.
+ *
+ * Should only be called with target_oid and target_oloc (as opposed to
+ * base_oid and base_oloc), since tiering isn't taken into account.
  */
-int ceph_oloc_oid_to_pg(struct ceph_osdmap *osdmap,
-			struct ceph_object_locator *oloc,
+int ceph_object_locator_to_pg(struct ceph_osdmap *osdmap,
 			      struct ceph_object_id *oid,
-			struct ceph_pg *pg_out)
+			      struct ceph_object_locator *oloc,
+			      struct ceph_pg *raw_pgid)
 {
 	struct ceph_pg_pool_info *pi;
 
-	pi = __lookup_pg_pool(&osdmap->pg_pools, oloc->pool);
+	pi = ceph_pg_pool_by_id(osdmap, oloc->pool);
 	if (!pi)
-		return -EIO;
+		return -ENOENT;
 
-	pg_out->pool = oloc->pool;
-	pg_out->seed = ceph_str_hash(pi->object_hash, oid->name,
+	raw_pgid->pool = oloc->pool;
+	raw_pgid->seed = ceph_str_hash(pi->object_hash, oid->name,
 				       oid->name_len);
 
-	dout("%s %*pE pgid %llu.%x\n", __func__, oid->name_len, oid->name,
-	     pg_out->pool, pg_out->seed);
+	dout("%s %*pE -> raw_pgid %llu.%x\n", __func__, oid->name_len,
+	     oid->name, raw_pgid->pool, raw_pgid->seed);
 	return 0;
 }
-EXPORT_SYMBOL(ceph_oloc_oid_to_pg);
+EXPORT_SYMBOL(ceph_object_locator_to_pg);
 
 static int do_crush(struct ceph_osdmap *map, int ruleno, int x,
 		    int *result, int result_max,