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Date: Thu, 04 Jan 2007 00:51:06 +0200
From: Diomidis Spinellis <dds@aueb.gr>
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To: John Baldwin <jhb@freebsd.org>
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Cc: freebsd-hackers@freebsd.org
Subject: Re: Filesystem layering
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John Baldwin wrote:
> On Wednesday 03 January 2007 12:04, Diomidis Spinellis wrote:
>> static int
>> umap_bypass(ap)
>>      struct vop_generic_args /* {
>>          struct vnodeop_desc *a_desc;
>>          <other random data follows, presumably>
>>      } */ *ap;
>> {
>> 	/* ... */
> 
> In this magic code here this function changes the vnode pointers in
> ap.

I presume you mean the part starting with the comment:

         /*
          * Map the vnodes going in.
          * Later, we'll invoke the operation based on
          * the first mapped vnode's operation vector.
          */

Thanks!  I don't think I'd guess it by reading the code; I was looking 
for a a simple assignment or indirection.  My next plan was to add 
debugging statements along the way, which would have been quite painful.

Diomidis