cdir moves out of the namei data structure
[unix-history] / usr / src / sys / vm / vm_pager.h
CommitLineData
619edcce
KM
1/*
2 * Copyright (c) 1990 University of Utah.
3 * Copyright (c) 1991 The Regents of the University of California.
4 * All rights reserved.
5 *
6 * This code is derived from software contributed to Berkeley by
7 * the Systems Programming Group of the University of Utah Computer
8 * Science Department.
9 *
10 * %sccs.include.redist.c%
11 *
12 * @(#)vm_pager.h 7.1 (Berkeley) %G%
13 */
14
15/*
16 * Pager routine interface definition.
17 * For BSD we use a cleaner version of the internal pager interface.
18 */
19
20#ifndef _VM_PAGER_
21#define _VM_PAGER_
22
23#ifdef KERNEL
24#include "types.h"
25#include "queue.h"
26#else
27#include <sys/types.h>
28#include <sys/queue.h>
29#endif
30
31struct pager_struct {
32 queue_head_t pg_list; /* links for list management */
33 caddr_t pg_handle; /* external handle (vp, dev, fp) */
34 int pg_type; /* type of pager */
35 struct pagerops *pg_ops; /* pager operations */
36 caddr_t pg_data; /* private pager data */
37};
38typedef struct pager_struct *vm_pager_t;
39
40#define vm_pager_null ((vm_pager_t) 0) /* XXX MACH compat */
41#define VM_PAGER_NULL ((vm_pager_t) 0)
42
43/* pager types */
44#define PG_DFLT -1
45#define PG_SWAP 0
46#define PG_VNODE 1
47#define PG_DEVICE 2
48
49struct pagerops {
50 void (*pgo_init)(); /* initialize pager */
51 vm_pager_t (*pgo_alloc)(); /* allocate pager */
52 void (*pgo_dealloc)(); /* disassociate */
53 int (*pgo_getpage)(); /* get (read) page */
54 int (*pgo_putpage)(); /* put (write) page */
55 boolean_t (*pgo_haspage)(); /* does pager have page? */
56};
57#define PAGER_OPS_NULL ((struct pagerops *)0)
58
59/*
60 * get/put return values
61 * OK operation was successful
62 * BAD specified data was out of the accepted range
63 * FAIL specified data was in range, but doesn't exist
64 * PEND operations was initiated but not completed
65 */
66#define VM_PAGER_OK 0
67#define VM_PAGER_BAD 1
68#define VM_PAGER_FAIL 2
69#define VM_PAGER_PEND 3
70
71#define VM_PAGER_ALLOC(h, s, p) (*(pg)->pg_ops->pgo_alloc)(h, s, p)
72#define VM_PAGER_DEALLOC(pg) (*(pg)->pg_ops->pgo_dealloc)(pg)
73#define VM_PAGER_GET(pg, m, s) (*(pg)->pg_ops->pgo_getpage)(pg, m, s)
74#define VM_PAGER_PUT(pg, m, s) (*(pg)->pg_ops->pgo_putpage)(pg, m, s)
75#define VM_PAGER_HASPAGE(pg, o) (*(pg)->pg_ops->pgo_haspage)(pg, o)
76
77#ifdef KERNEL
78vm_pager_t vm_pager_allocate();
79void vm_pager_deallocate();
80int vm_pager_get();
81int vm_pager_put();
82boolean_t vm_pager_has_page();
83
84vm_offset_t vm_pager_map_page();
85void vm_pager_unmap_page();
86vm_pager_t vm_pager_lookup();
87void vm_pager_sync();
88
89extern struct pagerops *dfltpagerops;
90#endif
91
92#endif /* _VM_PAGER_ */