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 <[email protected]> --- 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
