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Date: Mon, 04 May 2009 18:28:07 +0300
From: Boaz Harrosh <bharrosh@panasas.com>
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To: Jeff Garzik <jeff@garzik.org>
CC: James Bottomley <James.Bottomley@HansenPartnership.com>,
       Matthew Wilcox <matthew@wil.cx>, Jens Axboe <jens.axboe@oracle.com>,
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       linux-scsi@vger.kernel.org,
       Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>, Mark Lord <lkml@rtr.ca>
Subject: Re: New TRIM/UNMAP tree published (2009-05-02)
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On 05/04/2009 01:47 AM, Jeff Garzik wrote:
> James Bottomley wrote:
>> The ideal for REQ_TYPE_DISCARD seems to be to force a page allocation
>> tied to a bio when it's issued at the top.  That way everyone has enough
>> memory when it comes down the stack (both extents and WRITE SAME sector
>> will fit into a page ... although only just for WRITE SAME on 4k
>> sectors).
> 
> Makes sense...
> 
> 	Jeff
> 

I second that, let the allocator of the request supply a buffer and free it
on return/done. Perhaps with a general helper that does all that.

Boaz