1>>>>>>>>>> The TCM v4 fabric module script generator <<<<<<<<<<
  2
  3Greetings all,
  4
  5This document is intended to be a mini-HOWTO for using the tcm_mod_builder.py
  6script to generate a brand new functional TCM v4 fabric .ko module of your very own,
  7that once built can be immediately be loaded to start access the new TCM/ConfigFS
  8fabric skeleton, by simply using:
  9
 10	modprobe $TCM_NEW_MOD
 11	mkdir -p /sys/kernel/config/target/$TCM_NEW_MOD
 12
 13This script will create a new drivers/target/$TCM_NEW_MOD/, and will do the following
 14
 15	*) Generate new API callers for drivers/target/target_core_fabric_configs.c logic
 16	   ->make_tpg(), ->drop_tpg(), ->make_wwn(), ->drop_wwn().  These are created
 17	   into $TCM_NEW_MOD/$TCM_NEW_MOD_configfs.c
 18	*) Generate basic infrastructure for loading/unloading LKMs and TCM/ConfigFS fabric module
 19	   using a skeleton struct target_core_fabric_ops API template.
 20	*) Based on user defined T10 Proto_Ident for the new fabric module being built,
 21	   the TransportID / Initiator and Target WWPN related handlers for
 22	   SPC-3 persistent reservation are automatically generated in $TCM_NEW_MOD/$TCM_NEW_MOD_fabric.c
 23	   using drivers/target/target_core_fabric_lib.c logic.
 24	*) NOP API calls for all other Data I/O path and fabric dependent attribute logic
 25	   in $TCM_NEW_MOD/$TCM_NEW_MOD_fabric.c
 26
 27tcm_mod_builder.py depends upon the mandatory '-p $PROTO_IDENT' and '-m
 28$FABRIC_MOD_name' parameters, and actually running the script looks like:
 29
 30target:/mnt/sdb/lio-core-2.6.git/Documentation/target# python tcm_mod_builder.py -p iSCSI -m tcm_nab5000
 31tcm_dir: /mnt/sdb/lio-core-2.6.git/Documentation/target/../../
 32Set fabric_mod_name: tcm_nab5000
 33Set fabric_mod_dir:
 34/mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000
 35Using proto_ident: iSCSI
 36Creating fabric_mod_dir:
 37/mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000
 38Writing file:
 39/mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000/tcm_nab5000_base.h
 40Using tcm_mod_scan_fabric_ops:
 41/mnt/sdb/lio-core-2.6.git/Documentation/target/../../include/target/target_core_fabric_ops.h
 42Writing file:
 43/mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000/tcm_nab5000_fabric.c
 44Writing file:
 45/mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000/tcm_nab5000_fabric.h
 46Writing file:
 47/mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000/tcm_nab5000_configfs.c
 48Writing file:
 49/mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000/Kbuild
 50Writing file:
 51/mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000/Kconfig
 52Would you like to add tcm_nab5000to drivers/target/Kbuild..? [yes,no]: yes
 53Would you like to add tcm_nab5000to drivers/target/Kconfig..? [yes,no]: yes
 54
 55At the end of tcm_mod_builder.py. the script will ask to add the following
 56line to drivers/target/Kbuild:
 57
 58	obj-$(CONFIG_TCM_NAB5000)       += tcm_nab5000/
 59
 60and the same for drivers/target/Kconfig:
 61
 62	source "drivers/target/tcm_nab5000/Kconfig"
 63
 64*) Run 'make menuconfig' and select the new CONFIG_TCM_NAB5000 item:
 65
 66	<M>   TCM_NAB5000 fabric module
 67
 68*) Build using 'make modules', once completed you will have:
 69
 70target:/mnt/sdb/lio-core-2.6.git# ls -la drivers/target/tcm_nab5000/
 71total 1348
 72drwxr-xr-x 2 root root   4096 2010-10-05 03:23 .
 73drwxr-xr-x 9 root root   4096 2010-10-05 03:22 ..
 74-rw-r--r-- 1 root root    282 2010-10-05 03:22 Kbuild
 75-rw-r--r-- 1 root root    171 2010-10-05 03:22 Kconfig
 76-rw-r--r-- 1 root root     49 2010-10-05 03:23 modules.order
 77-rw-r--r-- 1 root root    738 2010-10-05 03:22 tcm_nab5000_base.h
 78-rw-r--r-- 1 root root   9096 2010-10-05 03:22 tcm_nab5000_configfs.c
 79-rw-r--r-- 1 root root 191200 2010-10-05 03:23 tcm_nab5000_configfs.o
 80-rw-r--r-- 1 root root  40504 2010-10-05 03:23 .tcm_nab5000_configfs.o.cmd
 81-rw-r--r-- 1 root root   5414 2010-10-05 03:22 tcm_nab5000_fabric.c
 82-rw-r--r-- 1 root root   2016 2010-10-05 03:22 tcm_nab5000_fabric.h
 83-rw-r--r-- 1 root root 190932 2010-10-05 03:23 tcm_nab5000_fabric.o
 84-rw-r--r-- 1 root root  40713 2010-10-05 03:23 .tcm_nab5000_fabric.o.cmd
 85-rw-r--r-- 1 root root 401861 2010-10-05 03:23 tcm_nab5000.ko
 86-rw-r--r-- 1 root root    265 2010-10-05 03:23 .tcm_nab5000.ko.cmd
 87-rw-r--r-- 1 root root    459 2010-10-05 03:23 tcm_nab5000.mod.c
 88-rw-r--r-- 1 root root  23896 2010-10-05 03:23 tcm_nab5000.mod.o
 89-rw-r--r-- 1 root root  22655 2010-10-05 03:23 .tcm_nab5000.mod.o.cmd
 90-rw-r--r-- 1 root root 379022 2010-10-05 03:23 tcm_nab5000.o
 91-rw-r--r-- 1 root root    211 2010-10-05 03:23 .tcm_nab5000.o.cmd
 92
 93*) Load the new module, create a lun_0 configfs group, and add new TCM Core
 94   IBLOCK backstore symlink to port:
 95
 96target:/mnt/sdb/lio-core-2.6.git# insmod drivers/target/tcm_nab5000.ko
 97target:/mnt/sdb/lio-core-2.6.git# mkdir -p /sys/kernel/config/target/nab5000/iqn.foo/tpgt_1/lun/lun_0
 98target:/mnt/sdb/lio-core-2.6.git# cd /sys/kernel/config/target/nab5000/iqn.foo/tpgt_1/lun/lun_0/
 99target:/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
100
101target:/sys/kernel/config/target/nab5000/iqn.foo/tpgt_1/lun/lun_0# cd -
102target:/mnt/sdb/lio-core-2.6.git# tree /sys/kernel/config/target/nab5000/
103/sys/kernel/config/target/nab5000/
104|-- discovery_auth
105|-- iqn.foo
106|   `-- tpgt_1
107|       |-- acls
108|       |-- attrib
109|       |-- lun
110|       |   `-- lun_0
111|       |       |-- alua_tg_pt_gp
112|       |       |-- alua_tg_pt_offline
113|       |       |-- alua_tg_pt_status
114|       |       |-- alua_tg_pt_write_md
115|	|	`-- nab5000_port -> ../../../../../../target/core/iblock_0/lvm_test0
116|       |-- np
117|       `-- param
118`-- version
119
120target:/mnt/sdb/lio-core-2.6.git# lsmod
121Module                  Size  Used by
122tcm_nab5000             3935  4
123iscsi_target_mod      193211  0
124target_core_stgt        8090  0
125target_core_pscsi      11122  1
126target_core_file        9172  2
127target_core_iblock      9280  1
128target_core_mod       228575  31
129tcm_nab5000,iscsi_target_mod,target_core_stgt,target_core_pscsi,target_core_file,target_core_iblock
130libfc                  73681  0
131scsi_debug             56265  0
132scsi_tgt                8666  1 target_core_stgt
133configfs               20644  2 target_core_mod
134
135----------------------------------------------------------------------
136
137Future TODO items:
138
139	*) Add more T10 proto_idents
140	*) Make tcm_mod_dump_fabric_ops() smarter and generate function pointer
141	   defs directly from include/target/target_core_fabric_ops.h:struct target_core_fabric_ops
142	   structure members.
143
144October 5th, 2010
145Nicholas A. Bellinger <nab@linux-iscsi.org>