0001 =========================================
0002 The TCM v4 fabric module script generator
0003 =========================================
0004
0005 Greetings all,
0006
0007 This document is intended to be a mini-HOWTO for using the tcm_mod_builder.py
0008 script to generate a brand new functional TCM v4 fabric .ko module of your very own,
0009 that once built can be immediately be loaded to start access the new TCM/ConfigFS
0010 fabric skeleton, by simply using::
0011
0012 modprobe $TCM_NEW_MOD
0013 mkdir -p /sys/kernel/config/target/$TCM_NEW_MOD
0014
0015 This script will create a new drivers/target/$TCM_NEW_MOD/, and will do the following
0016
0017 1) Generate new API callers for drivers/target/target_core_fabric_configs.c logic
0018 ->make_tpg(), ->drop_tpg(), ->make_wwn(), ->drop_wwn(). These are created
0019 into $TCM_NEW_MOD/$TCM_NEW_MOD_configfs.c
0020 2) Generate basic infrastructure for loading/unloading LKMs and TCM/ConfigFS fabric module
0021 using a skeleton struct target_core_fabric_ops API template.
0022 3) Based on user defined T10 Proto_Ident for the new fabric module being built,
0023 the TransportID / Initiator and Target WWPN related handlers for
0024 SPC-3 persistent reservation are automatically generated in $TCM_NEW_MOD/$TCM_NEW_MOD_fabric.c
0025 using drivers/target/target_core_fabric_lib.c logic.
0026 4) NOP API calls for all other Data I/O path and fabric dependent attribute logic
0027 in $TCM_NEW_MOD/$TCM_NEW_MOD_fabric.c
0028
0029 tcm_mod_builder.py depends upon the mandatory '-p $PROTO_IDENT' and '-m
0030 $FABRIC_MOD_name' parameters, and actually running the script looks like::
0031
0032 target:/mnt/sdb/lio-core-2.6.git/Documentation/target# python tcm_mod_builder.py -p iSCSI -m tcm_nab5000
0033 tcm_dir: /mnt/sdb/lio-core-2.6.git/Documentation/target/../../
0034 Set fabric_mod_name: tcm_nab5000
0035 Set fabric_mod_dir:
0036 /mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000
0037 Using proto_ident: iSCSI
0038 Creating fabric_mod_dir:
0039 /mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000
0040 Writing file:
0041 /mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000/tcm_nab5000_base.h
0042 Using tcm_mod_scan_fabric_ops:
0043 /mnt/sdb/lio-core-2.6.git/Documentation/target/../../include/target/target_core_fabric_ops.h
0044 Writing file:
0045 /mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000/tcm_nab5000_fabric.c
0046 Writing file:
0047 /mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000/tcm_nab5000_fabric.h
0048 Writing file:
0049 /mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000/tcm_nab5000_configfs.c
0050 Writing file:
0051 /mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000/Kbuild
0052 Writing file:
0053 /mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000/Kconfig
0054 Would you like to add tcm_nab5000to drivers/target/Kbuild..? [yes,no]: yes
0055 Would you like to add tcm_nab5000to drivers/target/Kconfig..? [yes,no]: yes
0056
0057 At the end of tcm_mod_builder.py. the script will ask to add the following
0058 line to drivers/target/Kbuild::
0059
0060 obj-$(CONFIG_TCM_NAB5000) += tcm_nab5000/
0061
0062 and the same for drivers/target/Kconfig::
0063
0064 source "drivers/target/tcm_nab5000/Kconfig"
0065
0066 #) Run 'make menuconfig' and select the new CONFIG_TCM_NAB5000 item::
0067
0068 <M> TCM_NAB5000 fabric module
0069
0070 #) Build using 'make modules', once completed you will have::
0071
0072 target:/mnt/sdb/lio-core-2.6.git# ls -la drivers/target/tcm_nab5000/
0073 total 1348
0074 drwxr-xr-x 2 root root 4096 2010-10-05 03:23 .
0075 drwxr-xr-x 9 root root 4096 2010-10-05 03:22 ..
0076 -rw-r--r-- 1 root root 282 2010-10-05 03:22 Kbuild
0077 -rw-r--r-- 1 root root 171 2010-10-05 03:22 Kconfig
0078 -rw-r--r-- 1 root root 49 2010-10-05 03:23 modules.order
0079 -rw-r--r-- 1 root root 738 2010-10-05 03:22 tcm_nab5000_base.h
0080 -rw-r--r-- 1 root root 9096 2010-10-05 03:22 tcm_nab5000_configfs.c
0081 -rw-r--r-- 1 root root 191200 2010-10-05 03:23 tcm_nab5000_configfs.o
0082 -rw-r--r-- 1 root root 40504 2010-10-05 03:23 .tcm_nab5000_configfs.o.cmd
0083 -rw-r--r-- 1 root root 5414 2010-10-05 03:22 tcm_nab5000_fabric.c
0084 -rw-r--r-- 1 root root 2016 2010-10-05 03:22 tcm_nab5000_fabric.h
0085 -rw-r--r-- 1 root root 190932 2010-10-05 03:23 tcm_nab5000_fabric.o
0086 -rw-r--r-- 1 root root 40713 2010-10-05 03:23 .tcm_nab5000_fabric.o.cmd
0087 -rw-r--r-- 1 root root 401861 2010-10-05 03:23 tcm_nab5000.ko
0088 -rw-r--r-- 1 root root 265 2010-10-05 03:23 .tcm_nab5000.ko.cmd
0089 -rw-r--r-- 1 root root 459 2010-10-05 03:23 tcm_nab5000.mod.c
0090 -rw-r--r-- 1 root root 23896 2010-10-05 03:23 tcm_nab5000.mod.o
0091 -rw-r--r-- 1 root root 22655 2010-10-05 03:23 .tcm_nab5000.mod.o.cmd
0092 -rw-r--r-- 1 root root 379022 2010-10-05 03:23 tcm_nab5000.o
0093 -rw-r--r-- 1 root root 211 2010-10-05 03:23 .tcm_nab5000.o.cmd
0094
0095 #) Load the new module, create a lun_0 configfs group, and add new TCM Core
0096 IBLOCK backstore symlink to port::
0097
0098 target:/mnt/sdb/lio-core-2.6.git# insmod drivers/target/tcm_nab5000.ko
0099 target:/mnt/sdb/lio-core-2.6.git# mkdir -p /sys/kernel/config/target/nab5000/iqn.foo/tpgt_1/lun/lun_0
0100 target:/mnt/sdb/lio-core-2.6.git# cd /sys/kernel/config/target/nab5000/iqn.foo/tpgt_1/lun/lun_0/
0101 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
0102
0103 target:/sys/kernel/config/target/nab5000/iqn.foo/tpgt_1/lun/lun_0# cd -
0104 target:/mnt/sdb/lio-core-2.6.git# tree /sys/kernel/config/target/nab5000/
0105 /sys/kernel/config/target/nab5000/
0106 |-- discovery_auth
0107 |-- iqn.foo
0108 | `-- tpgt_1
0109 | |-- acls
0110 | |-- attrib
0111 | |-- lun
0112 | | `-- lun_0
0113 | | |-- alua_tg_pt_gp
0114 | | |-- alua_tg_pt_offline
0115 | | |-- alua_tg_pt_status
0116 | | |-- alua_tg_pt_write_md
0117 | | `-- nab5000_port -> ../../../../../../target/core/iblock_0/lvm_test0
0118 | |-- np
0119 | `-- param
0120 `-- version
0121
0122 target:/mnt/sdb/lio-core-2.6.git# lsmod
0123 Module Size Used by
0124 tcm_nab5000 3935 4
0125 iscsi_target_mod 193211 0
0126 target_core_stgt 8090 0
0127 target_core_pscsi 11122 1
0128 target_core_file 9172 2
0129 target_core_iblock 9280 1
0130 target_core_mod 228575 31
0131 tcm_nab5000,iscsi_target_mod,target_core_stgt,target_core_pscsi,target_core_file,target_core_iblock
0132 libfc 73681 0
0133 scsi_debug 56265 0
0134 scsi_tgt 8666 1 target_core_stgt
0135 configfs 20644 2 target_core_mod
0136
0137 ----------------------------------------------------------------------
0138
0139 Future TODO items
0140 =================
0141
0142 1) Add more T10 proto_idents
0143 2) Make tcm_mod_dump_fabric_ops() smarter and generate function pointer
0144 defs directly from include/target/target_core_fabric_ops.h:struct target_core_fabric_ops
0145 structure members.
0146
0147 October 5th, 2010
0148
0149 Nicholas A. Bellinger <nab@linux-iscsi.org>
