SCSI layers in kernel
I am trying to learn about iSCSI. As iSCSI is a protocol that carries "SCSI" commands over the TCP protocol, therefore, it is also important to have a profound knowledge of SCSI. I have come across these following lines from a iSCSI research paper by IBM:
"We also had in mind a certain layering of the SCSI subsystem that seems to be prevalent in a number of Operating Systems. There are 3 layers to the SCSI subsystem. There is one high-level (class) driver for each type of SCSI device: disk, tape, CD, etc. There is a mid-level (port) driver that has common code for all types of devices, which takes care of command timeouts and serialization of commands. The low-level (miniport) driver is specific to an adapter, and must provide a queuecommand() or dispatch() routine that is used by the mid-level driver. "
The question is: Is it still relevant to latest versions of Kernel? I mean there are still three layers of SCSI subsystem in latest linux kernel.
I will be really grateful to have your answer
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