Date: Wed, 26 Jun 1996 12:44:52 +0200 (MET DST) From: Nicolas.Souchu@prism.uvsq.fr (Nicolas SOUCHU) To: hackers@freebsd.org Subject: SCSI polling mode and user process requests. Message-ID: <199606261044.MAA28406@angrand.prism.uvsq.fr>
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Hi, The SCSI stuff seems not to support polling mode for user process requests. Two return values are available to the scsi adapter when its scsi_cmd() function ends : - SUCCEFULLY_QUEUED - or COMPLETE COMPLETE means the request was polled and now everything is done. SUCCEFULLY_QUEUED means the request is queued. In the first case (COMPLETE), nothing is done by the SCSI upper stuff to wake up processes and such things, the command is supposed to be requested by the kernel. In the second case, a process requested the command then it should be waked up later by the scsi_done() function called by the scsi adapter driver interrupt when the command is complete. My driver runs only in polling mode yet... :^( There are conflicts between the COMPLETE return value and the scsi_done() call in adapter_do_scsi_cmd() necessary to wake up processes... Has anybody ever deal with this ? nicolas -- Nicolas.Souchu@prism.uvsq.fr -- http://www.prism.uvsq.fr/son~ Laboratoire PRiSM - Versailles, FRANCE
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