From 3f99306337ba1871afc8568e8b36004ce3cee039 Mon Sep 17 00:00:00 2001 From: Nicholas Bellinger Date: Wed, 6 Mar 2013 21:53:26 -0800 Subject: iscsi-target: Add iscsit_transport API template Add basic struct iscsit_transport API template to allow iscsi-target for running with external transport modules using existing iscsi_target_core.h code. For all external modules, this calls try_module_get() and module_put() to obtain + release an external iscsit_transport module reference count. Also include the iscsi-target symbols necessary in iscsi_transport.h to allow external transport modules to function. v3 changes: - Add iscsit_build_reject export for ISTATE_SEND_REJECT usage v2 changes: - Drop unnecessary export of iscsit_get_transport + iscsit_put_transport (roland) - Add ->iscsit_queue_data_in() to remove extra context switch on RDMA_WRITE - Add ->iscsit_queue_status() to remove extra context switch on IB_SEND status - Add ->iscsit_get_dataout() to remove extra context switch on RDMA_READ - Drop ->iscsit_free_cmd() - Drop ->iscsit_unmap_cmd() - Rename iscsit_create_transport() -> iscsit_register_transport() (andy) - Rename iscsit_destroy_transport() -> iscsit_unregister_transport() (andy) Signed-off-by: Nicholas Bellinger --- drivers/target/iscsi/Makefile | 3 +- drivers/target/iscsi/iscsi_target_transport.c | 55 +++++++++++++++++++++++++++ 2 files changed, 57 insertions(+), 1 deletion(-) create mode 100644 drivers/target/iscsi/iscsi_target_transport.c (limited to 'drivers') diff --git a/drivers/target/iscsi/Makefile b/drivers/target/iscsi/Makefile index 5b9a2cf7f0a9..13a92403fe3e 100644 --- a/drivers/target/iscsi/Makefile +++ b/drivers/target/iscsi/Makefile @@ -15,6 +15,7 @@ iscsi_target_mod-y += iscsi_target_parameters.o \ iscsi_target_util.o \ iscsi_target.o \ iscsi_target_configfs.o \ - iscsi_target_stat.o + iscsi_target_stat.o \ + iscsi_target_transport.o obj-$(CONFIG_ISCSI_TARGET) += iscsi_target_mod.o diff --git a/drivers/target/iscsi/iscsi_target_transport.c b/drivers/target/iscsi/iscsi_target_transport.c new file mode 100644 index 000000000000..882728fac30c --- /dev/null +++ b/drivers/target/iscsi/iscsi_target_transport.c @@ -0,0 +1,55 @@ +#include +#include +#include + +static LIST_HEAD(g_transport_list); +static DEFINE_MUTEX(transport_mutex); + +struct iscsit_transport *iscsit_get_transport(int type) +{ + struct iscsit_transport *t; + + mutex_lock(&transport_mutex); + list_for_each_entry(t, &g_transport_list, t_node) { + if (t->transport_type == type) { + if (t->owner && !try_module_get(t->owner)) { + t = NULL; + } + mutex_unlock(&transport_mutex); + return t; + } + } + mutex_unlock(&transport_mutex); + + return NULL; +} + +void iscsit_put_transport(struct iscsit_transport *t) +{ + if (t->owner) + module_put(t->owner); +} + +int iscsit_register_transport(struct iscsit_transport *t) +{ + INIT_LIST_HEAD(&t->t_node); + + mutex_lock(&transport_mutex); + list_add_tail(&t->t_node, &g_transport_list); + mutex_unlock(&transport_mutex); + + pr_debug("Registered iSCSI transport: %s\n", t->name); + + return 0; +} +EXPORT_SYMBOL(iscsit_register_transport); + +void iscsit_unregister_transport(struct iscsit_transport *t) +{ + mutex_lock(&transport_mutex); + list_del(&t->t_node); + mutex_unlock(&transport_mutex); + + pr_debug("Unregistered iSCSI transport: %s\n", t->name); +} +EXPORT_SYMBOL(iscsit_unregister_transport); -- cgit v1.2.3-55-g7522