This patch contains documentation for QLogic target mode add-on. Signed-off-by: Vladislav Bolkhovitin <vst@xxxxxxxx> --- /Documentation/scst/README.qla2x00t | 117 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 117 insertions(+) diff -uprN orig/linux-2.6.27/Documentation/scst/README.qla2x00t linux-2.6.27/Documentation/scst/README.qla2x00t --- orig/linux-2.6.27/Documentation/scst/README.qla2x00t +++ linux-2.6.27/Documentation/scst/README.qla2x00t @@ -0,0 +1,117 @@ +Target driver for Qlogic 2200/2300 Fibre Channel cards +====================================================== + +Version 1.0.1, XX XXXX 2008 +--------------------------- + +This driver has all required features and looks to be quite stable (for +beta) and useful. It consists from two parts: the target mode driver +itself and the changed initiator driver from Linux kernel, which is, +particularly, intended to perform all the initialization and shutdown +tasks. This driver was changed to provide the target mode support and +all necessary callbacks, but it's still capable to work as initiator +only. Mode, when a host acts as the initiator and the target +simultaneously, is supported as well. + +This version is compatible with SCST core version 1.0.1 and higher and +Linux kernel 2.6.27 and higher. Backport patches to kernels earlier than +2.6.27 are welcome. + +The original initiator driver was taken from the kernel 2.6.27. + +If you need to use this driver on kernels prior 2.6.27, it is +recommended to use version 1.0.0.x of this driver, taken from branch +1.0.0.x. For 2.6.26 you can also use version of this driver from SVN +trunk/ revision 577. + +See also "ToDo" file for list of known issues and unimplemented +features. + +Installation +------------ + +Only vanilla kernels from kernel.org are supported, but it should work +on vendors' kernels, if you manage to successfully compile on them. The +main problem with vendor's kernels is that they often contain patches, +which will appear only in the next version of the vanilla kernel, +therefore it's quite hard to track such changes. Thus, if during +compilation for some vendor kernel your compiler complains about +redefinition of some symbol, you should either switch to vanilla kernel, +or change as necessary the corresponding to that symbol "#if +LINUX_VERSION_CODE" statement. + +At first, make sure that the link "/lib/modules/`you_kernel_version`/build" +points to the source code for your currently running kernel. + +Then you should replace (or link) by the initiator driver from this +package "qla2xxx" subdirectory in kernel_source/drivers/scsi/ of the +currently running kernel and using your favorite kernel configuration +tool enable in the QLogic QLA2XXX Fibre Channel driver target mode +support (CONFIG_SCSI_QLA2XXX_TARGET). Then rebuild the kernel and its +modules. During this step you will compile the initiator driver. To +install it, install the built kernel and its modules. + +Then edit qla2x00-target/Makefile and set SCST_INC_DIR variable to point +to the directory, where SCST's public include files are located. If you +install QLA2x00 target driver's source code in the SCST's directory, +then SCST_INC_DIR will be set correctly for you. + +Also you can set SCST_DIR variable to the directory, where SCST was +built, but this is optional. If you don't set it or set incorrectly, +during the compilation you will get a bunch of harmless warnings like +"WARNING: "scst_rx_data" [/XXX/qla2x00tgt.ko] undefined!" + +To compile the target driver, type 'make' in qla2x00-target/ +subdirectory. It will build qla2x00tgt.ko module. + +To install the target driver, type 'make install' in qla2x00-target/ +subdirectory. The target driver will be installed in +/lib/modules/`you_kernel_version`/extra. To uninstall it, type 'make +uninstall'. + +After the drivers are loaded and adapters successfully initialized by +the initiator driver, including firmware image load, the target mode +should be enabled via a sysfs interface on a per card basis. Under the +appropriate scsi_host there is an entry target_mode_enabled, where you +should write "1", like: + +echo "1" >/sys/class/scsi_host/host0/target_mode_enabled + +Then you should configure exported devices using the corresponding +interface of SCST core. It is highly recommended to use scstadmin +utility for that purpose. + +Compilation options +------------------- + +There are the following compilation options, that could be commented +in/out in Makefile: + + - CONFIG_SCST_DEBUG - turns on some debugging code, including some logging. + Makes the driver considerably bigger and slower, producing large amount of + log data. + + - CONFIG_SCST_TRACING - turns on ability to log events. Makes the driver + considerably bigger and leads to some performance loss. + + - CONFIG_QLA_TGT_DEBUG_WORK_IN_THREAD - makes SCST process incoming + commands from the qla2x00t target driver and call the driver's + callbacks in internal SCST threads context instead of SIRQ context, + where those commands were received. Useful for debugging and lead to + some performance loss. + +Credits +------- + +Thanks to + + * Nathaniel Clark <nate@xxxxxxxxxx> for porting to new 2.6 kernel +initiator driver. + + * Mark Buechler <mark.buechler@xxxxxxxxx> for the original +WWN-based authentification, a lot of useful suggestions, bug reports and +help in debugging. + + * Ming Zhang <mingz@xxxxxxxxxxx> for his fixes. + +Vladislav Bolkhovitin <vst@xxxxxxxx>, http://scst.sourceforge.net -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
