freebsd-dev/sys/net/if_tapvar.h
Poul-Henning Kamp b0b0334878 Device megapatch 2/6:
This commit adds a couple of functions for pseudodrivers to use for
implementing cloning in a manner we will be able to lock down (shortly).

Basically what happens is that pseudo drivers get a way to ask for
"give me the dev_t with this unit number" or alternatively "give
me a dev_t with the lowest guaranteed free unit number" (there is
unfortunately a lot of non-POLA in the exact numeric value of this
number, just live with it for now)

Managing the unit number space this way removes the need to use
rman(9) to do so in the drivers this greatly simplifies the code in
the drivers because even using rman(9) they still needed to manage
their dev_t's anyway.

I have taken the if_tun, if_tap, snp and nmdm drivers through the
mill, partly because they (ab)used makedev(), but mostly because
together they represent three different problems for device-cloning:

if_tun and snp is the plain case: just give me a device.

if_tap has two kinds of devices, with a flag for device type.

nmdm has paired devices (ala pty) can you can clone either of them.
2004-02-21 20:29:52 +00:00

68 lines
2.5 KiB
C

/*
* Copyright (C) 1999-2000 by Maksim Yevmenkin <m_evmenkin@yahoo.com>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* BASED ON:
* -------------------------------------------------------------------------
*
* Copyright (c) 1998 Brian Somers <brian@Awfulhak.org>
* All rights reserved.
*
* Copyright (c) 1988, Julian Onions <jpo@cs.nott.ac.uk>
* Nottingham University 1987.
*/
/*
* $FreeBSD$
* $Id: if_tapvar.h,v 0.6 2000/07/11 02:16:08 max Exp $
*/
#ifndef _NET_IF_TAPVAR_H_
#define _NET_IF_TAPVAR_H_
struct tap_softc {
struct arpcom arpcom; /* ethernet common data */
#define tap_if arpcom.ac_if
struct resource *tap_unit; /* unit */
u_short tap_flags; /* misc flags */
#define TAP_OPEN (1 << 0)
#define TAP_INITED (1 << 1)
#define TAP_RWAIT (1 << 2)
#define TAP_ASYNC (1 << 3)
#define TAP_READY (TAP_OPEN|TAP_INITED)
#define TAP_VMNET (1 << 4)
u_int8_t ether_addr[ETHER_ADDR_LEN]; /* ether addr of the remote side */
pid_t tap_pid; /* PID of process to open */
struct sigio *tap_sigio; /* information for async I/O */
struct selinfo tap_rsel; /* read select */
SLIST_ENTRY(tap_softc) tap_next; /* next device in chain */
dev_t tap_dev;
};
#endif /* !_NET_IF_TAPVAR_H_ */