So many ways to send SCSI requests to a driver

(Please excuse the recycled bits.  The 7-month-old is still absorbing most of my blogging time (along with sleeping time, dating time, playing time, cleaning time, working time, etc…)) A question came up on the ntdev mailing list about why there are "so many" ways to send an I/O request to a SCSI driver. In matter…

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