freebsd-skq/sys/vm/vnode_pager.h
msmith 15e6194107 In the author's words:
These diffs implement the first stage of a VOP_{GET|PUT}PAGES pushdown
for local media FS's.

See ffs_putpages in /sys/ufs/ufs/ufs_readwrite.c for implementation
details for generic *_{get|put}pages for local media FS's.  Support
is trivial to add for any FS that formerly relied on the default
behaviour of the vnode_pager in in EOPNOTSUPP cases (just copy the
ffs_getpages() code for the FS in question's *_{get|put}pages).

Obviously, it would be better if each local media FS implemented a
more optimal method, instead of calling an exported interface from
the /sys/vm/vnode_pager.c, but this is a necessary first step in
getting the FS's to a point where they can be supplied with better
implementations on a case-by-case basis.

Obviously, the cd9660_putpages() can be rather trivial (since it
is a read-only FS type 8-)).

A slight (temporary) modification is made to print a diagnostic message
in the case where the underlying filesystem attempts to engage in the
previous behaviour.  Failure is likely to be ungraceful.

Submitted by:	terry@freebsd.org (Terry Lambert)
1998-02-26 06:39:59 +00:00

62 lines
2.7 KiB
C

/*
* Copyright (c) 1990 University of Utah.
* Copyright (c) 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* the Systems Programming Group of the University of Utah Computer
* Science Department.
*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
*
* @(#)vnode_pager.h 8.1 (Berkeley) 6/11/93
* $Id: vnode_pager.h,v 1.10 1997/02/22 09:48:43 peter Exp $
*/
#ifndef _VNODE_PAGER_
#define _VNODE_PAGER_ 1
#ifdef KERNEL
vm_object_t vnode_pager_alloc __P((void *, vm_size_t, vm_prot_t, vm_ooffset_t));
void vnode_pager_freepage __P((vm_page_t m));
struct vnode *vnode_pager_lock __P((vm_object_t));
/*
* XXX Generic routines; currently called by badly written FS code; these
* XXX should go away soon.
*/
int vnode_pager_generic_getpages __P((struct vnode *vp, vm_page_t *m,
int count, int reqpage));
int vnode_pager_generic_putpages __P((struct vnode *vp, vm_page_t *m,
int count, boolean_t sync,
int *rtvals));
#endif
#endif /* _VNODE_PAGER_ */