cmd_per_lun

The SCSI standard supports the notion of ``linked commands.'' Linked commands allow several commands to be queued consecutively to a single SCSI device. The 28 variable specifies the number of linked commands allowed. This variable should be set to 1 if command linking is not supported. At this time, however, the high-level SCSI code will not take advantage of this feature. Linked commands are fundamentally different from multiple outstanding commands (as described by the 29 variable). Linked commands always go to the same SCSI target and do not necessarily involve a RESELECTION phase. Further, linked commands eliminate the ARBITRATION, SELECTION, and MESSAGE OUT phases on all commands after the first one in the set. In contrast, multiple outstanding commands may be sent to an arbitrary SCSI target, and <#1276#> require<#1276#> the ARBITRATION, SELECTION, MESSAGE OUT, and RESELECTION phases.