This patch contains documentation for scst_local driver. Signed-off-by: Richard Sharpe <realrichardsharpe@xxxxxxxxx> Signed-off-by: Vladislav Bolkhovitin <vst@xxxxxxxx> --- Documentation/scst/README.scst_local | 95 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 95 insertions(+) diff -uprN orig/linux-2.6.27/Documentation/scst/README.scst_local linux-2.6.27/Documentation/scst/README.scst_local --- orig/linux-2.6.27/Documentation/scst/README.scst_local +++ linux-2.6.27/Documentation/scst/README.scst_local @@ -0,0 +1,95 @@ +SCST Debug ... +Richard Sharpe, 30-Nov-2008 + +This is the SCST Local driver. Its function is to allow you to access devices +that are exported via SCST directly on the same Linux system that they are +exported from. + +No assumptions are made in the code about the device types on the target, so +any device handlers that you load in SCST should be visible, including tapes +and so forth. + +To build, simply issue 'make' in the scst-local directory. + +Try 'modinfo scst_local' for a listing of module parameters so far. + +NOTE! This is now part of scst and supports being built in the scst tree. + +Here is how I have used it so far: + +1. Load up scst: + + modprobe scst + modprobe scst_vdisk + +2. Create a virtual disk (or your own device handler): + + dd if=/dev/zero of=/some/path/vdisk1.img bs=16384 count=1000000 +# dd if=/dev/zero of=/some/path/vdisk2.img bs=16384 count=1000000 + echo "open vm_disk1 /some/path/vdisk1.img" > /proc/scsi_tgt/vdisk/vdisk +# echo "open vm_disk2 /some/path/vdisk2.img" > /proc/scsi_tgt/vdisk/vdisk + echo "add vm_disk1 0" > /proc/scsi_tgt/groups/Default/devices +# echo "add vm_disk2 1" > /proc/scsi_tgt/groups/Default/devices + +3. Load the scst_local driver: + + insmod scst_local +# insmod scst_local max_luns=8 + +4. Check what you have + + cat /proc/scsi/scsi + Attached devices: + Host: scsi0 Channel: 00 Id: 00 Lun: 00 + Vendor: ATA Model: ST9320320AS Rev: 0303 + Type: Direct-Access ANSI SCSI revision: 05 + Host: scsi4 Channel: 00 Id: 00 Lun: 00 + Vendor: TSSTcorp Model: CD/DVDW TS-L632D Rev: TO04 + Type: CD-ROM ANSI SCSI revision: 05 + Host: scsi7 Channel: 00 Id: 00 Lun: 00 + Vendor: SCST_FIO Model: vm_disk1 Rev: 101 + Type: Direct-Access ANSI SCSI revision: 04 + +5. Have fun. + +Some of this was coded while in Santa Clara, some in Bangalore, and some in +Hyderabad. Noe doubt some will be coded on the way back to Santa Clara. + +The code still has bugs, so if you encounter any, email me the fixes at: + + realrichardsharpe@xxxxxxxxx + +I am thinking of renaming this to something more interesting. + +6. Change log + +V0.1 24-Sep-2008 (Hyderabad) Initial coding, pretty chatty and messy, + but worked. + +V0.2 25-Sep-2008 (Hong Kong) Cleaned up the code a lot, reduced the log + chatter, fixed a bug where multiple LUNs did not + work. Also, added logging control. Tested with + five virtual disks. They all came up as /dev/sdb + through /dev/sdf and I could dd to them. Also + fixed a bug preventing multiple adapters. + +V0.3 26-Sep-2008 (Santa Clara) Added back a copyright plus cleaned up some + unused functions and structures. + +V0.4 5-Oct-2008 (Santa Clara) Changed name to scst_local as suggested, cleaned + up some unused variables (made them used) and + change allocation to a kmem_cache pool. + +V0.5 5-Oct-2008 (Santa Clara) Added mgmt commands to handle dev reset and + aborts. Not sure if aborts works. Also corrected + the version info and renamed readme to README. + +V0.6 7-Oct-2008 (Santa Clara) Removed some redundant code and made some + changes suggested by Vladislav. + +V0.7 11-Oct-2008 (Santa Clara) Moved into the scst tree. Cleaned up some + unused functions, used TRACE macros etc. + +V0.9 30-Nov-2008 (Mtn View) Cleaned up an additional problem with symbols not + being defined in older version of the kernel. Also + fixed some English and cleaned up this doc. -- 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
