Hi Amit > download sg3-utils and its source code. good place to begin with. Thanks for the reply. I believe the sg3-utils uses the linux sg driver which does not provide any abstraction and sends commands directly to the device. what i was looking was more of protocol specific information and explaination of the flow like how block device read , write requests are converted into Commands and how those SCSI commands are passed to the lower layer. My target is FPGA board which has a pci interface for host controller . can u give me some pointers to understand the below ? Warm Regards, Ravi Kulkanri. > > On Mon, Aug 1, 2011 at 2:41 PM, RKK <kulkarni.ravi4@xxxxxxxxx> wrote: >> HI all, >> Im working on a storage protocol which uses SCSI commands set as >> the command set and also the SCSI Task Management functions for >> processing the Task Management. >> The Architectural Model is based on SAM-5. The Command set is based on >> SPC-4 and SBC-3. I have some doubts in trying to understanding some >> SCSI terms and definitions. >> >> For using the send command transport protocol service request to >> request a initiator the following API is defined >> >> [1]Send SCSI Command (IN (I_T_L_Q Nexus, CDB, Task Attribute, [Data-in >> Buffer Size], [Data- >> out Buffer], [Data-out Buffer Size], [CRN], [Command Priority], [First >> Burst Enabled])) >> >> Here I want to know what relation does the I_T_L_Q tries to convey. >> from what it says in SAM-5 Specification section 4.8 tries to define >> the Nexus as " nexus represents a relationship between a SCSI >> initiator port, a SCSI target port, optionally a logical unit, >> and optionally a command." >> how do we convey this information in the above [1]. >> Also can someone help me in how to map the initiator-target relation >> to host-device structure? thanks. >> >> Warm Regards, >> Ravi Kulkarni. >> >> >> >> >> >> Warm Regards, >> Ravi Kulkarni. >> >> _______________________________________________ >> Kernelnewbies mailing list >> Kernelnewbies@xxxxxxxxxxxxxxxxx >> http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies >> > -- Warm Regards, Ravi . "I don't Know is not a excuse , its an opportunity." _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
