From 3f99306337ba1871afc8568e8b36004ce3cee039 Mon Sep 17 00:00:00 2001 From: Nicholas Bellinger Date: Wed, 6 Mar 2013 21:53:26 -0800 Subject: [PATCH] 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 ++++++++++++ include/target/iscsi/iscsi_transport.h | 83 +++++++++++++++++++ 3 files changed, 140 insertions(+), 1 deletion(-) create mode 100644 drivers/target/iscsi/iscsi_target_transport.c create mode 100644 include/target/iscsi/iscsi_transport.h 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); diff --git a/include/target/iscsi/iscsi_transport.h b/include/target/iscsi/iscsi_transport.h new file mode 100644 index 000000000000..23a87d0cd72c --- /dev/null +++ b/include/target/iscsi/iscsi_transport.h @@ -0,0 +1,83 @@ +#include +#include +#include "../../../drivers/target/iscsi/iscsi_target_core.h" + +struct iscsit_transport { +#define ISCSIT_TRANSPORT_NAME 16 + char name[ISCSIT_TRANSPORT_NAME]; + int transport_type; + struct module *owner; + struct list_head t_node; + int (*iscsit_setup_np)(struct iscsi_np *, struct __kernel_sockaddr_storage *); + int (*iscsit_accept_np)(struct iscsi_np *, struct iscsi_conn *); + void (*iscsit_free_np)(struct iscsi_np *); + void (*iscsit_free_conn)(struct iscsi_conn *); + struct iscsi_cmd *(*iscsit_alloc_cmd)(struct iscsi_conn *, gfp_t); + int (*iscsit_get_login_rx)(struct iscsi_conn *, struct iscsi_login *); + int (*iscsit_put_login_tx)(struct iscsi_conn *, struct iscsi_login *, u32); + int (*iscsit_immediate_queue)(struct iscsi_conn *, struct iscsi_cmd *, int); + int (*iscsit_response_queue)(struct iscsi_conn *, struct iscsi_cmd *, int); + int (*iscsit_get_dataout)(struct iscsi_conn *, struct iscsi_cmd *, bool); + int (*iscsit_queue_data_in)(struct iscsi_conn *, struct iscsi_cmd *); + int (*iscsit_queue_status)(struct iscsi_conn *, struct iscsi_cmd *); +}; + +/* + * From iscsi_target_transport.c + */ + +extern int iscsit_register_transport(struct iscsit_transport *); +extern void iscsit_unregister_transport(struct iscsit_transport *); +extern struct iscsit_transport *iscsit_get_transport(int); +extern void iscsit_put_transport(struct iscsit_transport *); + +/* + * From iscsi_target.c + */ +extern int iscsit_add_reject_from_cmd(u8, int, int, unsigned char *, + struct iscsi_cmd *); +extern int iscsit_setup_scsi_cmd(struct iscsi_conn *, struct iscsi_cmd *, + unsigned char *); +extern void iscsit_set_unsoliticed_dataout(struct iscsi_cmd *); +extern int iscsit_process_scsi_cmd(struct iscsi_conn *, struct iscsi_cmd *, + struct iscsi_scsi_req *); +extern int iscsit_check_dataout_hdr(struct iscsi_conn *, unsigned char *, + struct iscsi_cmd **); +extern int iscsit_check_dataout_payload(struct iscsi_cmd *, struct iscsi_data *, + bool); +extern int iscsit_handle_nop_out(struct iscsi_conn *, struct iscsi_cmd *, + unsigned char *); +extern int iscsit_handle_logout_cmd(struct iscsi_conn *, struct iscsi_cmd *, + unsigned char *); +extern int iscsit_handle_task_mgt_cmd(struct iscsi_conn *, struct iscsi_cmd *, + unsigned char *); +extern void iscsit_build_rsp_pdu(struct iscsi_cmd *, struct iscsi_conn *, + bool, struct iscsi_scsi_rsp *); +extern void iscsit_build_nopin_rsp(struct iscsi_cmd *, struct iscsi_conn *, + struct iscsi_nopin *, bool); +extern void iscsit_build_task_mgt_rsp(struct iscsi_cmd *, struct iscsi_conn *, + struct iscsi_tm_rsp *); +extern void iscsit_build_reject(struct iscsi_cmd *, struct iscsi_conn *, + struct iscsi_reject *); +extern int iscsit_build_logout_rsp(struct iscsi_cmd *, struct iscsi_conn *, + struct iscsi_logout_rsp *); +extern int iscsit_logout_post_handler(struct iscsi_cmd *, struct iscsi_conn *); +/* + * From iscsi_target_device.c + */ +extern void iscsit_increment_maxcmdsn(struct iscsi_cmd *, struct iscsi_session *); +/* + * From iscsi_target_erl1.c + */ +extern void iscsit_stop_dataout_timer(struct iscsi_cmd *); + +/* + * From iscsi_target_tmr.c + */ +extern int iscsit_tmr_post_handler(struct iscsi_cmd *, struct iscsi_conn *); + +/* + * From iscsi_target_util.c + */ +extern struct iscsi_cmd *iscsit_allocate_cmd(struct iscsi_conn *, gfp_t); +extern int iscsit_sequence_cmd(struct iscsi_conn *, struct iscsi_cmd *, __be32); -- 2.20.1