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Date: Fri, 29 May 2009 14:56:51 -0400
From: Steve Rottinger <steve@pentek.com>
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Subject: O_DIRECT splice from PCI-resident buffer to filesystem
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Hi,

After some work, and kernel hacking, and thanks to Jens'
O_DIRECT/blockio splicing
patch,  I have been successful in using splice to transfer data directly
from a buffer
resident on a PCI device to a raw disk partition, with zero copies. Great!
Can anyone tell me if it is feasible to transfer data in the same way,
using splice
to a file, on a filesystem, instead of a raw block device with zero
copies?   Looking at
the code, it appears that the data is copied using memcpy, no matter what.

Thanks,

-Steve