|
Hi all, I'm struggling over how to interpret this rule
in section 1.2.2 of draft v10:
>>> The target MUST NOT transmit a
MaxCmdSN that is less than
the
last ExpCmdSN.
<<<
This confuses me because it says to me (in some
cases) that a target must be able to handle an unlimited number of
commands. For example, let's say the target has just about reached the
limit of the commands it can
handle:
T=>(Nop-In) (MaxCmdSN = 1, ExpCmdSN =
1)
I=>(Scsi Read Cmd) (CmdSN =
1)
T=>(Data-in) (MaxCmdSN = 1, ExpCmdSN = 2 /*
acknowledging scsi read cmd
*/)
Now the target may have many more data-ins to
transmit. But according to the rule, since the last ExpCmdSN the target
transmitted was 2, the target is now forced to send a MaxCmdSN of
2:
T=>(Data-in) (MaxCmdSN = 2, ExpCmdSN =
2)
But this allows the initiator to send another command,
even though the target can't handle
it!
Obviously something is wrong with my reasoning
here (perhaps my interpretation of 'last ExpCmdSN', or when I"m supposed to
acknowledge the scsi cmd); can anybody
clarify?
--buck
| 