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From: John Baldwin <jhb@freebsd.org>
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	(bigwig.baldwin.cx); Mon, 27 Aug 2012 14:40:38 -0400 (EDT)
Cc: Luigi Rizzo <rizzo@iet.unipi.it>, current@freebsd.org,
	Andriy Gapon <avg@freebsd.org>
Subject: Re: per file descriptor device callbacks ?
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On Monday, August 27, 2012 3:55:47 am Andriy Gapon wrote:
> on 27/08/2012 10:34 Luigi Rizzo said the following:
> > This requires to track calls to open/ioctl/poll/mmap/close.
> > The difficulty i have is with mmap() and close(), because FreeBSD
> > seems to handle these calls per-cdev rather than per-file-descriptor
> > (for instance, no 'struct file' argument is available in mmap(), and
> > the d_close method is only called on the last close() on the device).
> 
> devfs_set_cdevpriv(9), etc

mmap() is still problematic, but if you have the freedom to create your
own VM objects, then d_mmap_single() can let you handle that fairly
easily.


-- 
John Baldwin