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The TCM v4 fabric module script generator
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Greetings all,
This document is intended to be a mini-HOWTO for using the tcm_mod_builder.py
script to generate a brand new functional TCM v4 fabric .ko module of your very own,
that once built can be immediately be loaded to start access the new TCM/ConfigFS
fabric skeleton, by simply using::
modprobe $TCM_NEW_MOD
mkdir -p /sys/kernel/config/target/$TCM_NEW_MOD
This script will create a new drivers/target/$TCM_NEW_MOD/, and will do the following
1) Generate new API callers for drivers/target/target_core_fabric_configs.c logic
->make_tpg(), ->drop_tpg(), ->make_wwn(), ->drop_wwn(). These are created
into $TCM_NEW_MOD/$TCM_NEW_MOD_configfs.c
2) Generate basic infrastructure for loading/unloading LKMs and TCM/ConfigFS fabric module
using a skeleton struct target_core_fabric_ops API template.
3) Based on user defined T10 Proto_Ident for the new fabric module being built,
the TransportID / Initiator and Target WWPN related handlers for
SPC-3 persistent reservation are automatically generated in $TCM_NEW_MOD/$TCM_NEW_MOD_fabric.c
using drivers/target/target_core_fabric_lib.c logic.
4) NOP API calls for all other Data I/O path and fabric dependent attribute logic
in $TCM_NEW_MOD/$TCM_NEW_MOD_fabric.c
tcm_mod_builder.py depends upon the mandatory '-p $PROTO_IDENT' and '-m
$FABRIC_MOD_name' parameters, and actually running the script looks like::
target:/mnt/sdb/lio-core-2.6.git/Documentation/target# python tcm_mod_builder.py -p iSCSI -m tcm_nab5000
tcm_dir: /mnt/sdb/lio-core-2.6.git/Documentation/target/../../
Set fabric_mod_name: tcm_nab5000
Set fabric_mod_dir:
/mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000
Using proto_ident: iSCSI
Creating fabric_mod_dir:
/mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000
Writing file:
/mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000/tcm_nab5000_base.h
Using tcm_mod_scan_fabric_ops:
/mnt/sdb/lio-core-2.6.git/Documentation/target/../../include/target/target_core_fabric_ops.h
Writing file:
/mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000/tcm_nab5000_fabric.c
Writing file:
/mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000/tcm_nab5000_fabric.h
Writing file:
/mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000/tcm_nab5000_configfs.c
Writing file:
/mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000/Kbuild
Writing file:
/mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000/Kconfig
Would you like to add tcm_nab5000to drivers/target/Kbuild..? [yes,no]: yes
Would you like to add tcm_nab5000to drivers/target/Kconfig..? [yes,no]: yes
At the end of tcm_mod_builder.py. the script will ask to add the following
line to drivers/target/Kbuild::
obj-$(CONFIG_TCM_NAB5000) += tcm_nab5000/
and the same for drivers/target/Kconfig::
source "drivers/target/tcm_nab5000/Kconfig"
#) Run 'make menuconfig' and select the new CONFIG_TCM_NAB5000 item::
<M> TCM_NAB5000 fabric module
#) Build using 'make modules', once completed you will have::
target:/mnt/sdb/lio-core-2.6.git# ls -la drivers/target/tcm_nab5000/
total 1348
drwxr-xr-x 2 root root 4096 2010-10-05 03:23 .
drwxr-xr-x 9 root root 4096 2010-10-05 03:22 ..
-rw-r--r-- 1 root root 282 2010-10-05 03:22 Kbuild
-rw-r--r-- 1 root root 171 2010-10-05 03:22 Kconfig
-rw-r--r-- 1 root root 49 2010-10-05 03:23 modules.order
-rw-r--r-- 1 root root 738 2010-10-05 03:22 tcm_nab5000_base.h
-rw-r--r-- 1 root root 9096 2010-10-05 03:22 tcm_nab5000_configfs.c
-rw-r--r-- 1 root root 191200 2010-10-05 03:23 tcm_nab5000_configfs.o
-rw-r--r-- 1 root root 40504 2010-10-05 03:23 .tcm_nab5000_configfs.o.cmd
-rw-r--r-- 1 root root 5414 2010-10-05 03:22 tcm_nab5000_fabric.c
-rw-r--r-- 1 root root 2016 2010-10-05 03:22 tcm_nab5000_fabric.h
-rw-r--r-- 1 root root 190932 2010-10-05 03:23 tcm_nab5000_fabric.o
-rw-r--r-- 1 root root 40713 2010-10-05 03:23 .tcm_nab5000_fabric.o.cmd
-rw-r--r-- 1 root root 401861 2010-10-05 03:23 tcm_nab5000.ko
-rw-r--r-- 1 root root 265 2010-10-05 03:23 .tcm_nab5000.ko.cmd
-rw-r--r-- 1 root root 459 2010-10-05 03:23 tcm_nab5000.mod.c
-rw-r--r-- 1 root root 23896 2010-10-05 03:23 tcm_nab5000.mod.o
-rw-r--r-- 1 root root 22655 2010-10-05 03:23 .tcm_nab5000.mod.o.cmd
-rw-r--r-- 1 root root 379022 2010-10-05 03:23 tcm_nab5000.o
-rw-r--r-- 1 root root 211 2010-10-05 03:23 .tcm_nab5000.o.cmd
#) Load the new module, create a lun_0 configfs group, and add new TCM Core
IBLOCK backstore symlink to port::
target:/mnt/sdb/lio-core-2.6.git# insmod drivers/target/tcm_nab5000.ko
target:/mnt/sdb/lio-core-2.6.git# mkdir -p /sys/kernel/config/target/nab5000/iqn.foo/tpgt_1/lun/lun_0
target:/mnt/sdb/lio-core-2.6.git# cd /sys/kernel/config/target/nab5000/iqn.foo/tpgt_1/lun/lun_0/
target:/sys/kernel/config/target/nab5000/iqn.foo/tpgt_1/lun/lun_0# ln -s /sys/kernel/config/target/core/iblock_0/lvm_test0 nab5000_port
target:/sys/kernel/config/target/nab5000/iqn.foo/tpgt_1/lun/lun_0# cd -
target:/mnt/sdb/lio-core-2.6.git# tree /sys/kernel/config/target/nab5000/
/sys/kernel/config/target/nab5000/
|-- discovery_auth
|-- iqn.foo
| `-- tpgt_1
| |-- acls
| |-- attrib
| |-- lun
| | `-- lun_0
| | |-- alua_tg_pt_gp
| | |-- alua_tg_pt_offline
| | |-- alua_tg_pt_status
| | |-- alua_tg_pt_write_md
| | `-- nab5000_port -> ../../../../../../target/core/iblock_0/lvm_test0
| |-- np
| `-- param
`-- version
target:/mnt/sdb/lio-core-2.6.git# lsmod
Module Size Used by
tcm_nab5000 3935 4
iscsi_target_mod 193211 0
target_core_stgt 8090 0
target_core_pscsi 11122 1
target_core_file 9172 2
target_core_iblock 9280 1
target_core_mod 228575 31
tcm_nab5000,iscsi_target_mod,target_core_stgt,target_core_pscsi,target_core_file,target_core_iblock
libfc 73681 0
scsi_debug 56265 0
scsi_tgt 8666 1 target_core_stgt
configfs 20644 2 target_core_mod
----------------------------------------------------------------------
Future TODO items
=================
1) Add more T10 proto_idents
2) Make tcm_mod_dump_fabric_ops() smarter and generate function pointer
defs directly from include/target/target_core_fabric_ops.h:struct target_core_fabric_ops
structure members.
October 5th, 2010
Nicholas A. Bellinger <nab@linux-iscsi.org>