Subject: Re: Question about bus_dma and mbufs
To: Dave Huang <firstname.lastname@example.org>
From: Jason Thorpe <email@example.com>
Date: 07/04/2005 17:16:10
On Jul 4, 2005, at 3:55 PM, Dave Huang wrote:
> Is there a way for me to do this with the various bus_dma(9) and/or
> mbuf(9) routines, or will I have to copy the mbuf chain into my own
> buffer that has the necessary requirements?
There is a way to specify the max segments parameter, but bus_dma
will not automatically bounce for you... it would simply return
E2BIG, which would mean your driver would have to handle that.
Take a look at dev/ic/tulip.c, right around line 776 (in -current) to
see how the tlp driver handles situations like this.