nvme-fc: retry initial controller connections 3 times

Currently, if a frame is lost of command fails as part of initial
association create for a new controller, the new controller connection
request will immediately fail.

Add in an immediate 3 retry loop before giving up.

Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

1 files changed, 30 insertions, 2 deletions

diff --git a/drivers/nvme/host/fc.c b/drivers/nvme/host/fc.c
index 8182b1999f49..be49d0f79381 100644
--- a/drivers/nvme/host/fc.c
+++ b/drivers/nvme/host/fc.c
@@ -2734,7 +2734,7 @@ nvme_fc_init_ctrl(struct device *dev, struct nvmf_ctrl_options *opts,
 {
         struct nvme_fc_ctrl *ctrl;
         unsigned long flags;
-        int ret, idx;
+        int ret, idx, retry;
 
         if (!(rport->remoteport.port_role &
             (FC_PORT_ROLE_NVME_DISCOVERY | FC_PORT_ROLE_NVME_TARGET))) {
@@ -2826,9 +2826,37 @@ nvme_fc_init_ctrl(struct device *dev, struct nvmf_ctrl_options *opts,
         list_add_tail(&ctrl->ctrl_list, &rport->ctrl_list);
         spin_unlock_irqrestore(&rport->lock, flags);
 
-        ret = nvme_fc_create_association(ctrl);
+        /*
+         * It's possible that transactions used to create the association
+         * may fail. Examples: CreateAssociation LS or CreateIOConnection
+         * LS gets dropped/corrupted/fails; or a frame gets dropped or a
+         * command times out for one of the actions to init the controller
+         * (Connect, Get/Set_Property, Set_Features, etc). Many of these
+         * transport errors (frame drop, LS failure) inherently must kill
+         * the association. The transport is coded so that any command used
+         * to create the association (prior to a LIVE state transition
+         * while NEW or RECONNECTING) will fail if it completes in error or
+         * times out.
+         *
+         * As such: as the connect request was mostly likely due to a
+         * udev event that discovered the remote port, meaning there is
+         * not an admin or script there to restart if the connect
+         * request fails, retry the initial connection creation up to
+         * three times before giving up and declaring failure.
+         */
+        for (retry = 0; retry < 3; retry++) {
+                ret = nvme_fc_create_association(ctrl);
+                if (!ret)
+                        break;
+        }
+
         if (ret) {
+                /* couldn't schedule retry - fail out */
+                dev_err(ctrl->ctrl.device,
+                        "NVME-FC{%d}: Connect retry failed\n", ctrl->cnum);
+
                 ctrl->ctrl.opts = NULL;
+
                 /* initiate nvme ctrl ref counting teardown */
                 nvme_uninit_ctrl(&ctrl->ctrl);
                 nvme_put_ctrl(&ctrl->ctrl);