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Reschedule SRB after SRB_STATUS_BUSY

blangeblange Member Posts: 22

Hi. I have a questing regarding a filebacked virtual storport miniport driver.
For a read-only device I have a situation where I cannot answer a read request, yet. So I answer the request with SRB_STATUS_BUSY for a retry. At this point I would like to serve the next request in queue. However, I get the same request back after some delay and the queue is not processed further. Is there a way to resubmit the request to the tail of the SRB queue?
I saw some discussion here, where it was said to answer SRB_STATUS_BUSY followed by asking for the next request to the port driver. How can this be achieved?

Thanks for any helpful hint in advance.

Comments

  • RourkeRourke Member Posts: 62

    What exactly do you mean by "I cannot answer a read request"? Consider not reporting the media present until you can answer all read requests. Or if the device needs longer timeouts in general then extend them.

  • blangeblange Member Posts: 22
    Hello Rourke. In my case the requested data is not available, yet, but will be at a later time, which I cannot predict. So I want this request to be rescheduled.

    I looked a little more into the busy states and found aside the SRB_STATUS_BUSY also the SCSISTAT_BUSY. When both together are set in the SRB Response, it seems that the SRB queue continues and the next requests are passed on, as I intended. So SRB_STATUS_BUSY seems to put the request to the head of the queue. The combination seems to put the request back to the tail of the queue.
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