nvme-fcloop: add support for nvmet discovery_event op

Update fcloop to support the discovery_event operation and
invoke a nvme rescan. In a real fc adapter, this would generate an
RSCN, which the host would receive and convert into a nvme rescan
on the remote port specified in the rscn payload.

Signed-off-by: James Smart <jsmart2021@gmail.com>
[kbuild-bot: fcloop_tgt_discovery_evt can be static]
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Arun Easi <aeasi@marvell.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

diff --git a/drivers/nvme/target/fcloop.c b/drivers/nvme/target/fcloop.c
index 381b5a9..b8c1cc5 100644 (file)
--- a/drivers/nvme/target/fcloop.c
+++ b/drivers/nvme/target/fcloop.c
@@ -231,6 +231,11 @@ struct fcloop_lsreq {
        int                             status;
 };
 
+struct fcloop_rscn {
+       struct fcloop_tport             *tport;
+       struct work_struct              work;
+};
+
 enum {
        INI_IO_START            = 0,
        INI_IO_ACTIVE           = 1,
@@ -348,6 +353,37 @@ fcloop_xmt_ls_rsp(struct nvmet_fc_target_port *tport,
        return 0;
 }
 
+/*
+ * Simulate reception of RSCN and converting it to a initiator transport
+ * call to rescan a remote port.
+ */
+static void
+fcloop_tgt_rscn_work(struct work_struct *work)
+{
+       struct fcloop_rscn *tgt_rscn =
+               container_of(work, struct fcloop_rscn, work);
+       struct fcloop_tport *tport = tgt_rscn->tport;
+
+       if (tport->remoteport)
+               nvme_fc_rescan_remoteport(tport->remoteport);
+       kfree(tgt_rscn);
+}
+
+static void
+fcloop_tgt_discovery_evt(struct nvmet_fc_target_port *tgtport)
+{
+       struct fcloop_rscn *tgt_rscn;
+
+       tgt_rscn = kzalloc(sizeof(*tgt_rscn), GFP_KERNEL);
+       if (!tgt_rscn)
+               return;
+
+       tgt_rscn->tport = tgtport->private;
+       INIT_WORK(&tgt_rscn->work, fcloop_tgt_rscn_work);
+
+       schedule_work(&tgt_rscn->work);
+}
+
 static void
 fcloop_tfcp_req_free(struct kref *ref)
 {
@@ -839,6 +875,7 @@ static struct nvmet_fc_target_template tgttemplate = {
        .fcp_op                 = fcloop_fcp_op,
        .fcp_abort              = fcloop_tgt_fcp_abort,
        .fcp_req_release        = fcloop_fcp_req_release,
+       .discovery_event        = fcloop_tgt_discovery_evt,
        .max_hw_queues          = FCLOOP_HW_QUEUES,
        .max_sgl_segments       = FCLOOP_SGL_SEGS,
        .max_dif_sgl_segments   = FCLOOP_SGL_SEGS,