From owner-cvs-all  Thu Sep 16 23:10:30 1999
Delivered-To: cvs-all@freebsd.org
Received: from freefall.freebsd.org (freefall.FreeBSD.ORG [204.216.27.21])
	by hub.freebsd.org (Postfix) with ESMTP
	id 6860215494; Thu, 16 Sep 1999 23:10:28 -0700 (PDT)
	(envelope-from dillon@FreeBSD.org)
Received: (from dillon@localhost)
	by freefall.freebsd.org (8.9.3/8.9.2) id XAA56084;
	Thu, 16 Sep 1999 23:10:28 -0700 (PDT)
	(envelope-from dillon@FreeBSD.org)
Message-Id: <199909170610.XAA56084@freefall.freebsd.org>
From: Matt Dillon <dillon@FreeBSD.org>
Date: Thu, 16 Sep 1999 23:10:28 -0700 (PDT)
To: cvs-committers@FreeBSD.org, cvs-all@FreeBSD.org
Subject: cvs commit: src/sys/miscfs/specfs spec_vnops.c src/sys/sys vnode.h
         src/sys/kern vfs_subr.c
Sender: owner-cvs-all@FreeBSD.ORG
Precedence: bulk

dillon      1999/09/16 23:10:28 PDT

  Modified files:
    sys/miscfs/specfs    spec_vnops.c 
    sys/sys              vnode.h 
    sys/kern             vfs_subr.c 
  Log:
      Add vfs.enable_userblk_io sysctl to control whether user reads and writes
      to buffered block devices are allowed.  The default is to be backwards
      compatible, i.e. reads and writes are allowed.
  
      The idea is for a larger crowd to start running with this disabled and
      see what problems, if any, crop up, and then to change the default to
      off and see if any problems crop up in the next 6 months prior to
      potentially removing support entirely.  There are still a few people,
      Julian and myself included, who believe the buffered block device
      access from usermode to be useful.
  
      Remove use of vnode->v_lastr from buffered block device I/O in
      preparation for removal of vnode->v_lastr field, replacing it with
      the already existing seqcount metric to detect sequential operation.
  
  Reviewed by:	Alan Cox <alc@cs.rice.edu>, David Greenman <dg@root.com>
  
  Revision  Changes    Path
  1.108     +10 -5     src/sys/miscfs/specfs/spec_vnops.c
  1.100     +2 -1      src/sys/sys/vnode.h
  1.225     +4 -1      src/sys/kern/vfs_subr.c



To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe cvs-all" in the body of the message