LU-2017 mdc: add layout swap between 2 objects

[fs/lustre-release.git] / lustre / mdc / mdc_request.c

diff --git a/lustre/mdc/mdc_request.c b/lustre/mdc/mdc_request.c
index dc366af..df9376b 100644 (file)
--- a/lustre/mdc/mdc_request.c
+++ b/lustre/mdc/mdc_request.c
@@ -1702,6 +1702,63 @@ static int mdc_quotactl(struct obd_device *unused, struct obd_export *exp,
         RETURN(rc);
 }
 
+static int mdc_ioc_swap_layouts(struct obd_export *exp,
+                               struct md_op_data *op_data)
+{
+       CFS_LIST_HEAD(cancels);
+       struct ptlrpc_request   *req;
+       int                      rc, count;
+       struct mdc_swap_layouts *msl, *payload;
+       ENTRY;
+
+       msl = op_data->op_data;
+
+       /* When the MDT will get the MDS_SWAP_LAYOUTS RPC the
+        * first thing it will do is to cancel the 2 layout
+        * locks hold by this client.
+        * So the client must cancel its layout locks on the 2 fids
+        * with the request RPC to avoid extra RPC round trips
+        */
+       count = mdc_resource_get_unused(exp, &op_data->op_fid1, &cancels,
+                                       LCK_CR, MDS_INODELOCK_LAYOUT);
+       count += mdc_resource_get_unused(exp, &op_data->op_fid2, &cancels,
+                                        LCK_CR, MDS_INODELOCK_LAYOUT);
+
+       req = ptlrpc_request_alloc(class_exp2cliimp(exp),
+                                  &RQF_MDS_SWAP_LAYOUTS);
+       if (req == NULL) {
+               ldlm_lock_list_put(&cancels, l_bl_ast, count);
+               RETURN(-ENOMEM);
+       }
+
+       mdc_set_capa_size(req, &RMF_CAPA1, op_data->op_capa1);
+       mdc_set_capa_size(req, &RMF_CAPA2, op_data->op_capa2);
+
+       rc = mdc_prep_elc_req(exp, req, MDS_SWAP_LAYOUTS, &cancels, count);
+       if (rc) {
+               ptlrpc_request_free(req);
+               RETURN(rc);
+       }
+
+       mdc_swap_layouts_pack(req, op_data);
+
+       payload = req_capsule_client_get(&req->rq_pill, &RMF_SWAP_LAYOUTS);
+       LASSERT(payload);
+
+       *payload = *msl;
+
+       ptlrpc_request_set_replen(req);
+
+       rc = ptlrpc_queue_wait(req);
+       if (rc)
+               GOTO(out, rc);
+       EXIT;
+
+out:
+       ptlrpc_req_finished(req);
+       return rc;
+}
+
 static int mdc_iocontrol(unsigned int cmd, struct obd_export *exp, int len,
                          void *karg, void *uarg)
 {
@@ -1837,6 +1894,10 @@ static int mdc_iocontrol(unsigned int cmd, struct obd_export *exp, int len,
                else
                        GOTO(out, rc = 0);
        }
+       case LL_IOC_LOV_SWAP_LAYOUTS: {
+               rc = mdc_ioc_swap_layouts(exp, karg);
+               break;
+       }
         default:
                 CERROR("mdc_ioctl(): unrecognised ioctl %#x\n", cmd);
                 GOTO(out, rc = -ENOTTY);