A transport may have a transport-specific mechanism that can signal
when discovery controller content has changed and request a host
to reconnect to the discovery controller.
FC is such a transport. RSCNs may be generated by the FC port with
the discovery server, with the RSCNs then broadcast to the FC-NVME
hosts. A host, upon receiving the RSCN, would validate connectivity
then initiate a discovery controller rescan, allowing new subsystems
to be connected to or updating subsystem connectivity tables.
Modify the subsystem link/unlink routines to always call a new
nvmet_port_subsystem_chg() routine whenever a new subsystem is
linked to a port or removed from a port.
The nvmet_port_subsystem_chg() routine will look to see if the
transport supports a discovery change callback, and if so, calls
the callback.
Signed-off-by: James Smart <james.smart@xxxxxxxxxxxx>
---
drivers/nvme/target/configfs.c | 2 ++
drivers/nvme/target/core.c | 10 ++++++++++
drivers/nvme/target/nvmet.h | 2 ++
3 files changed, 14 insertions(+)
diff --git a/drivers/nvme/target/configfs.c b/drivers/nvme/target/configfs.c
index b6aeb1d70951..38adcd7eafb1 100644
--- a/drivers/nvme/target/configfs.c
+++ b/drivers/nvme/target/configfs.c
@@ -503,6 +503,7 @@ static int nvmet_port_subsys_allow_link(struct config_item *parent,
list_add_tail(&link->entry, &port->subsystems);
nvmet_genctr++;
up_write(&nvmet_config_sem);
+ nvmet_port_subsystem_chg(port);
return 0;
out_free_link:
@@ -529,6 +530,7 @@ static void nvmet_port_subsys_drop_link(struct config_item *parent,
found:
list_del(&p->entry);
nvmet_genctr++;
+ nvmet_port_subsystem_chg(port);
if (list_empty(&port->subsystems))
nvmet_disable_port(port);
up_write(&nvmet_config_sem);
diff --git a/drivers/nvme/target/core.c b/drivers/nvme/target/core.c
index da088293eafc..f70d900774d0 100644
--- a/drivers/nvme/target/core.c
+++ b/drivers/nvme/target/core.c
@@ -206,6 +206,16 @@ void nvmet_disable_port(struct nvmet_port *port)
module_put(ops->owner);
}
+void nvmet_port_subsystem_chg(struct nvmet_port *port)
+{
+ struct nvmet_fabrics_ops *ops;
+
+ ops = nvmet_transports[port->disc_addr.trtype];
+
+ if (ops->discov_chg)
+ ops->discov_chg(port);
+}
+
static void nvmet_keep_alive_timer(struct work_struct *work)
{
struct nvmet_ctrl *ctrl = container_of(to_delayed_work(work),
diff --git a/drivers/nvme/target/nvmet.h b/drivers/nvme/target/nvmet.h
index e342f02845c1..87c7f6e84694 100644
--- a/drivers/nvme/target/nvmet.h
+++ b/drivers/nvme/target/nvmet.h
@@ -209,6 +209,7 @@ struct nvmet_fabrics_ops {
int (*add_port)(struct nvmet_port *port);
void (*remove_port)(struct nvmet_port *port);
void (*delete_ctrl)(struct nvmet_ctrl *ctrl);
+ void (*discov_chg)(struct nvmet_port *port);
};
#define NVMET_MAX_INLINE_BIOVEC 8
@@ -302,6 +303,7 @@ void nvmet_unregister_transport(struct nvmet_fabrics_ops *ops);
int nvmet_enable_port(struct nvmet_port *port);
void nvmet_disable_port(struct nvmet_port *port);
+void nvmet_port_subsystem_chg(struct nvmet_port *port);
void nvmet_referral_enable(struct nvmet_port *parent, struct nvmet_port *port);
void nvmet_referral_disable(struct nvmet_port *port);
--
2.13.1
