nvme-fc: Revert "add module to ops template to allow module references"

The original patch was to resolve the lldd being able to be unloaded
while being used to talk to the boot device of the system. However, the
end result of the original patch is that any driver unload while a nvme
controller is live via the lldd is now being prohibited. Given the module
reference, the module teardown routine can't be called, thus there's no
way, other than manual actions to terminate the controllers.

Fixes: 863fbae9 ("nvme_fc: add module to ops template to allow module references")
Cc: <stable@vger.kernel.org> # v5.4+
Signed-off-by: James Smart <jsmart2021@gmail.com>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

drivers/nvme/host/fc.c

@@ -342,8 +342,7 @@ nvme_fc_register_localport(struct nvme_fc_port_info *pinfo,
 	    !template->ls_req || !template->fcp_io ||
 	    !template->ls_abort || !template->fcp_abort ||
 	    !template->max_hw_queues || !template->max_sgl_segments ||
-	    !template->max_dif_sgl_segments || !template->dma_boundary ||
-	    !template->module) {
+	    !template->max_dif_sgl_segments || !template->dma_boundary) {
 		ret = -EINVAL;
 		goto out_reghost_failed;
 	}
@@ -2016,7 +2015,6 @@ nvme_fc_ctrl_free(struct kref *ref)
 {
 	struct nvme_fc_ctrl *ctrl =
 		container_of(ref, struct nvme_fc_ctrl, ref);
-	struct nvme_fc_lport *lport = ctrl->lport;
 	unsigned long flags;
 
 	if (ctrl->ctrl.tagset) {
@@ -2043,7 +2041,6 @@ nvme_fc_ctrl_free(struct kref *ref)
 	if (ctrl->ctrl.opts)
 		nvmf_free_options(ctrl->ctrl.opts);
 	kfree(ctrl);
-	module_put(lport->ops->module);
 }
 
 static void
@@ -3074,15 +3071,10 @@ nvme_fc_init_ctrl(struct device *dev, struct nvmf_ctrl_options *opts,
 		goto out_fail;
 	}
 
-	if (!try_module_get(lport->ops->module)) {
-		ret = -EUNATCH;
-		goto out_free_ctrl;
-	}
-
 	idx = ida_simple_get(&nvme_fc_ctrl_cnt, 0, 0, GFP_KERNEL);
 	if (idx < 0) {
 		ret = -ENOSPC;
-		goto out_mod_put;
+		goto out_free_ctrl;
 	}
 
 	ctrl->ctrl.opts = opts;
@@ -3232,8 +3224,6 @@ nvme_fc_init_ctrl(struct device *dev, struct nvmf_ctrl_options *opts,
 out_free_ida:
 	put_device(ctrl->dev);
 	ida_simple_remove(&nvme_fc_ctrl_cnt, ctrl->cnum);
-out_mod_put:
-	module_put(lport->ops->module);
 out_free_ctrl:
 	kfree(ctrl);
 out_fail:

drivers/nvme/target/fcloop.c

@@ -875,7 +875,6 @@ fcloop_targetport_delete(struct nvmet_fc_target_port *targetport)
 #define FCLOOP_DMABOUND_4G		0xFFFFFFFF
 
 static struct nvme_fc_port_template fctemplate = {
-	.module			= THIS_MODULE,
 	.localport_delete	= fcloop_localport_delete,
 	.remoteport_delete	= fcloop_remoteport_delete,
 	.create_queue		= fcloop_create_queue,

drivers/scsi/lpfc/lpfc_nvme.c

@@ -1985,8 +1985,6 @@ lpfc_nvme_fcp_abort(struct nvme_fc_local_port *pnvme_lport,
 
 /* Declare and initialization an instance of the FC NVME template. */
 static struct nvme_fc_port_template lpfc_nvme_template = {
-	.module	= THIS_MODULE,
-
 	/* initiator-based functions */
 	.localport_delete  = lpfc_nvme_localport_delete,
 	.remoteport_delete = lpfc_nvme_remoteport_delete,

drivers/scsi/qla2xxx/qla_nvme.c

@@ -610,7 +610,6 @@ static void qla_nvme_remoteport_delete(struct nvme_fc_remote_port *rport)
 }
 
 static struct nvme_fc_port_template qla_nvme_fc_transport = {
-	.module	= THIS_MODULE,
 	.localport_delete = qla_nvme_localport_delete,
 	.remoteport_delete = qla_nvme_remoteport_delete,
 	.create_queue   = qla_nvme_alloc_queue,

include/linux/nvme-fc-driver.h

@@ -270,8 +270,6 @@ struct nvme_fc_remote_port {
  *
  * Host/Initiator Transport Entrypoints/Parameters:
  *
- * @module:  The LLDD module using the interface
- *
  * @localport_delete:  The LLDD initiates deletion of a localport via
  *       nvme_fc_deregister_localport(). However, the teardown is
  *       asynchronous. This routine is called upon the completion of the
@@ -385,8 +383,6 @@ struct nvme_fc_remote_port {
  *       Value is Mandatory. Allowed to be zero.
  */
 struct nvme_fc_port_template {
-	struct module	*module;
-
 	/* initiator-based functions */
 	void	(*localport_delete)(struct nvme_fc_local_port *);
 	void	(*remoteport_delete)(struct nvme_fc_remote_port *);