1========================================= 2The TCM v4 fabric module script generator 3========================================= 4 5Greetings all, 6 7This document is intended to be a mini-HOWTO for using the tcm_mod_builder.py 8script to generate a brand new functional TCM v4 fabric .ko module of your very own, 9that once built can be immediately be loaded to start access the new TCM/ConfigFS 10fabric skeleton, by simply using:: 11 12 modprobe $TCM_NEW_MOD 13 mkdir -p /sys/kernel/config/target/$TCM_NEW_MOD 14 15This script will create a new drivers/target/$TCM_NEW_MOD/, and will do the following 16 17 1) Generate new API callers for drivers/target/target_core_fabric_configs.c logic 18 ->make_tpg(), ->drop_tpg(), ->make_wwn(), ->drop_wwn(). These are created 19 into $TCM_NEW_MOD/$TCM_NEW_MOD_configfs.c 20 2) Generate basic infrastructure for loading/unloading LKMs and TCM/ConfigFS fabric module 21 using a skeleton struct target_core_fabric_ops API template. 22 3) Based on user defined T10 Proto_Ident for the new fabric module being built, 23 the TransportID / Initiator and Target WWPN related handlers for 24 SPC-3 persistent reservation are automatically generated in $TCM_NEW_MOD/$TCM_NEW_MOD_fabric.c 25 using drivers/target/target_core_fabric_lib.c logic. 26 4) NOP API calls for all other Data I/O path and fabric dependent attribute logic 27 in $TCM_NEW_MOD/$TCM_NEW_MOD_fabric.c 28 29tcm_mod_builder.py depends upon the mandatory '-p $PROTO_IDENT' and '-m 30$FABRIC_MOD_name' parameters, and actually running the script looks like:: 31 32 target:/mnt/sdb/lio-core-2.6.git/Documentation/target# python tcm_mod_builder.py -p iSCSI -m tcm_nab5000 33 tcm_dir: /mnt/sdb/lio-core-2.6.git/Documentation/target/../../ 34 Set fabric_mod_name: tcm_nab5000 35 Set fabric_mod_dir: 36 /mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000 37 Using proto_ident: iSCSI 38 Creating fabric_mod_dir: 39 /mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000 40 Writing file: 41 /mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000/tcm_nab5000_base.h 42 Using tcm_mod_scan_fabric_ops: 43 /mnt/sdb/lio-core-2.6.git/Documentation/target/../../include/target/target_core_fabric_ops.h 44 Writing file: 45 /mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000/tcm_nab5000_fabric.c 46 Writing file: 47 /mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000/tcm_nab5000_fabric.h 48 Writing file: 49 /mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000/tcm_nab5000_configfs.c 50 Writing file: 51 /mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000/Kbuild 52 Writing file: 53 /mnt/sdb/lio-core-2.6.git/Documentation/target/../../drivers/target/tcm_nab5000/Kconfig 54 Would you like to add tcm_nab5000to drivers/target/Kbuild..? [yes,no]: yes 55 Would you like to add tcm_nab5000to drivers/target/Kconfig..? [yes,no]: yes 56 57At the end of tcm_mod_builder.py. the script will ask to add the following 58line to drivers/target/Kbuild:: 59 60 obj-$(CONFIG_TCM_NAB5000) += tcm_nab5000/ 61 62and the same for drivers/target/Kconfig:: 63 64 source "drivers/target/tcm_nab5000/Kconfig" 65 66#) Run 'make menuconfig' and select the new CONFIG_TCM_NAB5000 item:: 67 68 <M> TCM_NAB5000 fabric module 69 70#) Build using 'make modules', once completed you will have:: 71 72 target:/mnt/sdb/lio-core-2.6.git# ls -la drivers/target/tcm_nab5000/ 73 total 1348 74 drwxr-xr-x 2 root root 4096 2010-10-05 03:23 . 75 drwxr-xr-x 9 root root 4096 2010-10-05 03:22 .. 76 -rw-r--r-- 1 root root 282 2010-10-05 03:22 Kbuild 77 -rw-r--r-- 1 root root 171 2010-10-05 03:22 Kconfig 78 -rw-r--r-- 1 root root 49 2010-10-05 03:23 modules.order 79 -rw-r--r-- 1 root root 738 2010-10-05 03:22 tcm_nab5000_base.h 80 -rw-r--r-- 1 root root 9096 2010-10-05 03:22 tcm_nab5000_configfs.c 81 -rw-r--r-- 1 root root 191200 2010-10-05 03:23 tcm_nab5000_configfs.o 82 -rw-r--r-- 1 root root 40504 2010-10-05 03:23 .tcm_nab5000_configfs.o.cmd 83 -rw-r--r-- 1 root root 5414 2010-10-05 03:22 tcm_nab5000_fabric.c 84 -rw-r--r-- 1 root root 2016 2010-10-05 03:22 tcm_nab5000_fabric.h 85 -rw-r--r-- 1 root root 190932 2010-10-05 03:23 tcm_nab5000_fabric.o 86 -rw-r--r-- 1 root root 40713 2010-10-05 03:23 .tcm_nab5000_fabric.o.cmd 87 -rw-r--r-- 1 root root 401861 2010-10-05 03:23 tcm_nab5000.ko 88 -rw-r--r-- 1 root root 265 2010-10-05 03:23 .tcm_nab5000.ko.cmd 89 -rw-r--r-- 1 root root 459 2010-10-05 03:23 tcm_nab5000.mod.c 90 -rw-r--r-- 1 root root 23896 2010-10-05 03:23 tcm_nab5000.mod.o 91 -rw-r--r-- 1 root root 22655 2010-10-05 03:23 .tcm_nab5000.mod.o.cmd 92 -rw-r--r-- 1 root root 379022 2010-10-05 03:23 tcm_nab5000.o 93 -rw-r--r-- 1 root root 211 2010-10-05 03:23 .tcm_nab5000.o.cmd 94 95#) Load the new module, create a lun_0 configfs group, and add new TCM Core 96 IBLOCK backstore symlink to port:: 97 98 target:/mnt/sdb/lio-core-2.6.git# insmod drivers/target/tcm_nab5000.ko 99 target:/mnt/sdb/lio-core-2.6.git# mkdir -p /sys/kernel/config/target/nab5000/iqn.foo/tpgt_1/lun/lun_0 100 target:/mnt/sdb/lio-core-2.6.git# cd /sys/kernel/config/target/nab5000/iqn.foo/tpgt_1/lun/lun_0/ 101 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 102 103 target:/sys/kernel/config/target/nab5000/iqn.foo/tpgt_1/lun/lun_0# cd - 104 target:/mnt/sdb/lio-core-2.6.git# tree /sys/kernel/config/target/nab5000/ 105 /sys/kernel/config/target/nab5000/ 106 |-- discovery_auth 107 |-- iqn.foo 108 | `-- tpgt_1 109 | |-- acls 110 | |-- attrib 111 | |-- lun 112 | | `-- lun_0 113 | | |-- alua_tg_pt_gp 114 | | |-- alua_tg_pt_offline 115 | | |-- alua_tg_pt_status 116 | | |-- alua_tg_pt_write_md 117 | | `-- nab5000_port -> ../../../../../../target/core/iblock_0/lvm_test0 118 | |-- np 119 | `-- param 120 `-- version 121 122 target:/mnt/sdb/lio-core-2.6.git# lsmod 123 Module Size Used by 124 tcm_nab5000 3935 4 125 iscsi_target_mod 193211 0 126 target_core_stgt 8090 0 127 target_core_pscsi 11122 1 128 target_core_file 9172 2 129 target_core_iblock 9280 1 130 target_core_mod 228575 31 131 tcm_nab5000,iscsi_target_mod,target_core_stgt,target_core_pscsi,target_core_file,target_core_iblock 132 libfc 73681 0 133 scsi_debug 56265 0 134 scsi_tgt 8666 1 target_core_stgt 135 configfs 20644 2 target_core_mod 136 137---------------------------------------------------------------------- 138 139Future TODO items 140================= 141 142 1) Add more T10 proto_idents 143 2) Make tcm_mod_dump_fabric_ops() smarter and generate function pointer 144 defs directly from include/target/target_core_fabric_ops.h:struct target_core_fabric_ops 145 structure members. 146 147October 5th, 2010 148 149Nicholas A. Bellinger <nab@linux-iscsi.org> 150