NetBSD/sys/uvm/uvm_object.h
thorpej 0ff8d3ac1a Define a new kernel object type, "intrsafe", which are used for objects
which can be used in an interrupt context.  Use pmap_kenter*() and
pmap_kremove() only for mappings owned by these objects.

Fixes some locking protocol issues related to MP support, and eliminates
all of the pmap_enter vs. pmap_kremove inconsistencies.
1999-05-25 20:30:08 +00:00

86 lines
3.5 KiB
C

/* $NetBSD: uvm_object.h,v 1.8 1999/05/25 20:30:09 thorpej Exp $ */
/*
*
* Copyright (c) 1997 Charles D. Cranor and Washington University.
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Charles D. Cranor and
* Washington University.
* 4. 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.
*
* from: Id: uvm_object.h,v 1.1.2.2 1998/01/04 22:44:51 chuck Exp
*/
#ifndef _UVM_UVM_OBJECT_H_
#define _UVM_UVM_OBJECT_H_
/*
* uvm_object.h
*/
/*
* uvm_object: all that is left of mach objects.
*/
struct uvm_object {
simple_lock_data_t vmobjlock; /* lock on memq */
struct uvm_pagerops *pgops; /* pager ops */
struct pglist memq; /* pages in this object */
int uo_npages; /* # of pages in memq */
int uo_refs; /* reference count */
};
/*
* UVM_OBJ_KERN is a 'special' uo_refs value which indicates that the
* object is a kernel memory object rather than a normal one (kernel
* memory objects don't have reference counts -- they never die).
*
* this value is used to detected kernel object mappings at uvm_unmap()
* time. normally when an object is unmapped its pages eventaully become
* deactivated and then paged out and/or freed. this is not useful
* for kernel objects... when a kernel object is unmapped we always want
* to free the resources associated with the mapping. UVM_OBJ_KERN
* allows us to decide which type of unmapping we want to do.
*
* in addition, we have kernel objects which may be used in an
* interrupt context. these objects get their mappings entered
* with pmap_kenter*() and removed with pmap_kremove(), which
* are safe to call in interrupt context, and must be used ONLY
* for wired kernel mappings in these objects and their associated
* maps.
*/
#define UVM_OBJ_KERN (-2)
#define UVM_OBJ_KERN_INTRSAFE (-3)
#define UVM_OBJ_IS_KERN_OBJECT(uobj) \
((uobj)->uo_refs == UVM_OBJ_KERN || \
(uobj)->uo_refs == UVM_OBJ_KERN_INTRSAFE)
#define UVM_OBJ_IS_INTRSAFE_OBJECT(uobj) \
((uobj)->uo_refs == UVM_OBJ_KERN_INTRSAFE)
#endif /* _UVM_UVM_OBJECT_H_ */