Re: [PATCH scsi-misc-2.6 07/08] scsi: remove bogus {get|put}_device()calls
From: Tejun Heo
Date: Wed Mar 23 2005 - 04:19:16 EST
Hi,
James Bottomley wrote:
On Wed, 2005-03-23 at 11:14 +0900, Tejun Heo wrote:
So, basically, SCSI high-level object (scsi_disk) and
mid-level object (scsi_device) are reference counted by users,
not the requests they submit. Reference count cannot go zero
with active users and users cannot access the object once the
reference count reaches zero.
Actually, no. Unfortunately we still have some fire and forget APIs, so
the contention that we always have an open refcounted descriptor isn't
always true.
Yeap, you're right. So, what we have is
* All high-level users have open access to the scsi high-level
object on issueing requests, but may close it before its requests
complete.
* All mid-layer users do get_device() before submitting requests,
but may put_device() before its requests complete.
Thanks for pointing that out. :-)
--
tejun
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