Linux SCSI layer, specifically SCSI mid layer is the place where all the conversion happens. There is a Linux - SCSI mailing list (linux-scsi) where you'll find relevant discussions. -Amit On Tue, Aug 2, 2011 at 12:15 PM, RKK <kulkarni.ravi4@xxxxxxxxx> wrote: > 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
