freebsd-skq/sys/vm/vm_radix.h
attilio a23ed68137 - Move VM_RADIX_STACK in vm_object.c because it is the only consumer
- Import the check for the return value of vm_radix_lookup() directly
  in the while removing the need to use a spourious check.
2012-07-08 23:50:57 +00:00

99 lines
2.9 KiB
C

/*
* Copyright (c) 2011 Jeffrey Roberson <jeff@freebsd.org>
* Copyright (c) 2008 Mayur Shardul <mayur.shardul@gmail.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.
*
*/
#ifndef _VM_RADIX_H_
#define _VM_RADIX_H_
/*
* Radix tree root. The height and pointer are set together to permit
* coherent lookups while the root is modified.
*/
struct vm_radix {
uintptr_t rt_root; /* root + height */
};
#ifdef _KERNEL
void vm_radix_init(void);
int vm_radix_insert(struct vm_radix *, vm_pindex_t, void *);
void *vm_radix_lookup(struct vm_radix *, vm_pindex_t);
int vm_radix_lookupn(struct vm_radix *, vm_pindex_t, vm_pindex_t, void **,
int, vm_pindex_t *, u_int *);
void *vm_radix_lookup_le(struct vm_radix *, vm_pindex_t);
void vm_radix_reclaim_allnodes(struct vm_radix *);
void vm_radix_remove(struct vm_radix *, vm_pindex_t);
/*
* Look up any entry at a position greater or equal to index.
*/
static inline void *
vm_radix_lookup_ge(struct vm_radix *rtree, vm_pindex_t index)
{
void *val;
u_int dummy;
if (vm_radix_lookupn(rtree, index, 0, &val, 1, &index, &dummy))
return (val);
return (NULL);
}
static inline void *
vm_radix_last(struct vm_radix *rtree)
{
return vm_radix_lookup_le(rtree, 0);
}
static inline void *
vm_radix_first(struct vm_radix *rtree)
{
return vm_radix_lookup_ge(rtree, 0);
}
static inline void *
vm_radix_next(struct vm_radix *rtree, vm_pindex_t index)
{
if (index == -1)
return (NULL);
return vm_radix_lookup_ge(rtree, index + 1);
}
static inline void *
vm_radix_prev(struct vm_radix *rtree, vm_pindex_t index)
{
if (index == 0)
return (NULL);
return vm_radix_lookup_le(rtree, index - 1);
}
#endif /* _KERNEL */
#endif /* !_VM_RADIX_H_ */