File:  [DragonFly] / src / sys / emulation / svr4 / Attic / svr4_types.h
Revision 1.3: download - view: text, annotated - select for diffs
Wed May 19 22:52:55 2004 UTC (10 years, 5 months ago) by dillon
Branches: MAIN
CVS tags: HEAD, DragonFly_Stable, DragonFly_Snap29Sep2004, DragonFly_Snap13Sep2004, DragonFly_RELEASE_1_4_Slip, DragonFly_RELEASE_1_4, DragonFly_RELEASE_1_2_Slip, DragonFly_RELEASE_1_2, DragonFly_1_0_REL, DragonFly_1_0_RC1, DragonFly_1_0A_REL
Device layer rollup commit.

* cdevsw_add() is now required.  cdevsw_add() and cdevsw_remove() may specify
  a mask/match indicating the range of supported minor numbers.  Multiple
  cdevsw_add()'s using the same major number, but distinctly different
  ranges, may be issued.  All devices that failed to call cdevsw_add() before
  now do.

* cdevsw_remove() now automatically marks all devices within its supported
  range as being destroyed.

* vnode->v_rdev is no longer resolved when the vnode is created.  Instead,
  only v_udev (a newly added field) is resolved.  v_rdev is resolved when
  the vnode is opened and cleared on the last close.

* A great deal of code was making rather dubious assumptions with regards
  to the validity of devices associated with vnodes, primarily due to
  the persistence of a device structure due to being indexed by (major, minor)
  instead of by (cdevsw, major, minor).  In particular, if you run a program
  which connects to a USB device and then you pull the USB device and plug
  it back in, the vnode subsystem will continue to believe that the device
  is open when, in fact, it isn't (because it was destroyed and recreated).

  In particular, note that all the VFS mount procedures now check devices
  via v_udev instead of v_rdev prior to calling VOP_OPEN(), since v_rdev
  is NULL prior to the first open.

* The disk layer's device interaction has been rewritten.  The disk layer
  (i.e. the slice and disklabel management layer) no longer overloads
  its data onto the device structure representing the underlying physical
  disk.  Instead, the disk layer uses the new cdevsw_add() functionality
  to register its own cdevsw using the underlying device's major number,
  and simply does NOT register the underlying device's cdevsw.  No
  confusion is created because the device hash is now based on
  (cdevsw,major,minor) rather then (major,minor).

  NOTE: This also means that underlying raw disk devices may use the entire
  device minor number instead of having to reserve the bits used by the disk
  layer, and also means that can we (theoretically) stack a fully
  disklabel-supported 'disk' on top of any block device.

* The new reference counting scheme prevents this by associating a device
  with a cdevsw and disconnecting the device from its cdevsw when the cdevsw
  is removed.  Additionally, all udev2dev() lookups run through the cdevsw
  mask/match and only successfully find devices still associated with an
  active cdevsw.

* Major work on MFS:  MFS no longer shortcuts vnode and device creation.  It
  now creates a real vnode and a real device and implements real open and
  close VOPs.  Additionally, due to the disk layer changes, MFS is no longer
  limited to 255 mounts.  The new limit is 16 million.  Since MFS creates a
  real device node, mount_mfs will now create a real /dev/mfs<PID> device
  that can be read from userland (e.g. so you can dump an MFS filesystem).

* BUF AND DEVICE STRATEGY changes.  The struct buf contains a b_dev field.
  In order to properly handle stacked devices we now require that the b_dev
  field be initialized before the device strategy routine is called.  This
  required some additional work in various VFS implementations.  To enforce
  this requirement, biodone() now sets b_dev to NODEV.  The new disk layer
  will adjust b_dev before forwarding a request to the actual physical
  device.

* A bug in the ISO CD boot sequence which resulted in a panic has been fixed.

Testing by: lots of people, but David Rhodus found the most aggregious bugs.

/*
 * Copyright (c) 1998 Mark Newton
 * Copyright (c) 1994 Christos Zoulas
 * 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.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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.
 * 
 * $FreeBSD: src/sys/svr4/svr4_types.h,v 1.3 1999/08/28 00:51:27 peter Exp $
 * $DragonFly: src/sys/emulation/svr4/svr4_types.h,v 1.3 2004/05/19 22:52:55 dillon Exp $
 */

#ifndef	_SVR4_TYPES_H_
#define	_SVR4_TYPES_H_

typedef u_quad_t	 svr4_ino64_t;
typedef quad_t		 svr4_off64_t;
typedef quad_t		 svr4_blkcnt64_t;
typedef u_quad_t	 svr4_fsblkcnt64_t;

typedef long  		 svr4_off_t;
typedef u_long		 svr4_dev_t;
typedef u_long		 svr4_ino_t;
typedef u_long		 svr4_mode_t;
typedef u_long		 svr4_nlink_t;
typedef long		 svr4_uid_t;
typedef long		 svr4_gid_t;
typedef long		 svr4_daddr_t;
typedef long		 svr4_pid_t;
typedef long		 svr4_time_t;
typedef long		 svr4_blkcnt_t;
typedef u_long		 svr4_fsblkcnt_t;
typedef char		*svr4_caddr_t;
typedef u_int		 svr4_size_t;

typedef short		 svr4_o_dev_t;
typedef short		 svr4_o_pid_t;
typedef u_short		 svr4_o_ino_t;
typedef u_short		 svr4_o_mode_t;
typedef short		 svr4_o_nlink_t;
typedef u_short		 svr4_o_uid_t;
typedef u_short		 svr4_o_gid_t;
typedef long		 svr4_clock_t;
typedef int		 svr4_key_t;

typedef struct timespec  svr4_timestruc_t;

#define svr4_omajor(x)        ((int32_t)((((x) & 0x7f00) >> 8)))
#define svr4_ominor(x)        ((int32_t)((((x) & 0x00ff) >> 0)))
#define svr4_omakedev(x,y)    ((svr4_o_dev_t)((((x) << 8) & 0x7f00) | \
					      (((y) << 0) & 0x00ff)))

#define svr4_to_bsd_odev_t(d) makeudev(svr4_omajor(d), svr4_ominor(d))
#define bsd_to_svr4_odev_t(d) svr4_omakedev(umajor(d), uminor(d))

#define svr4_major(x)         ((int32_t)((((x) & 0xfffc0000) >> 18)))
#define svr4_minor(x)         ((int32_t)((((x) & 0x0003ffff) >> 0)))
#define svr4_makedev(x,y)     ((svr4_dev_t)((((x) << 18) & 0xfffc0000) | \
					    (((y) << 0) & 0x0003ffff)))
#define svr4_to_bsd_dev_t(d)  makeudev(svr4_major(d), svr4_minor(d))
#define bsd_to_svr4_dev_t(d)  svr4_makedev(umajor(d), uminor(d))

#endif /* !_SVR4_TYPES_H_ */