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Date: Tue, 14 Mar 2017 10:09:05 +0100
From: Manuel =?iso-8859-1?Q?St=FChn?= <freebsdnewbie@freenet.de>
To: freebsd-hackers@freebsd.org
Subject: mmap device-drivers
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Hi,
is it possible for a device driver to keep track if there are still
active mmap() pointers pointing to that device?
  
Linux does have something like
  
struct vm_operations_struct vm_ops =
{
                .close = vm_close,
};
  
where vm_close gets called when any mmapped pointer goes out of scope and the
driver can refcount the mappers.
  
Is there something similar in freebsd?