From owner-freebsd-hackers  Thu Nov 29 12:20:46 2001
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Date: Thu, 29 Nov 2001 15:18:53 -0500 (EST)
From: Zhihui Zhang <zzhang@cs.binghamton.edu>
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To: freebsd-hackers@freebsd.org
Subject: contiguous memory of a buffer
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I am wondering whether we need contiguous memory for a PHYSICAL buffer to
perform the DMA I/O.  It seems not, because regular buffers can be
consisted of non-contiguous pages.  The disk driver should treat both
kinds of buffers in the same way.  So can I say that any buffers used by
kernel (via getblk()) is conforming DMA-able buffer?

Thanks for any clarification.

-Zhihui


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