uvm_object.h revision 1.31 1 /* $NetBSD: uvm_object.h,v 1.31 2011/06/12 03:36:03 rmind Exp $ */
2
3 /*
4 * Copyright (c) 1997 Charles D. Cranor and Washington University.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 *
27 * from: Id: uvm_object.h,v 1.1.2.2 1998/01/04 22:44:51 chuck Exp
28 */
29
30 #ifndef _UVM_UVM_OBJECT_H_
31 #define _UVM_UVM_OBJECT_H_
32
33 /*
34 * uvm_object.h
35 */
36
37 #include <sys/queue.h>
38 #include <sys/rbtree.h>
39 #include <uvm/uvm_pglist.h>
40
41 /*
42 * uvm_object: all that is left of mach objects.
43 */
44
45 struct uvm_object {
46 kmutex_t * vmobjlock; /* lock on memq */
47 const struct uvm_pagerops *pgops; /* pager ops */
48 struct pglist memq; /* pages in this object */
49 int uo_npages; /* # of pages in memq */
50 unsigned uo_refs; /* reference count */
51 struct rb_tree rb_tree; /* tree of pages */
52 LIST_HEAD(,ubc_map) uo_ubc; /* ubc mappings */
53 };
54
55 /*
56 * UVM_OBJ_KERN is a 'special' uo_refs value which indicates that the
57 * object is a kernel memory object rather than a normal one (kernel
58 * memory objects don't have reference counts -- they never die).
59 *
60 * this value is used to detected kernel object mappings at uvm_unmap()
61 * time. normally when an object is unmapped its pages eventaully become
62 * deactivated and then paged out and/or freed. this is not useful
63 * for kernel objects... when a kernel object is unmapped we always want
64 * to free the resources associated with the mapping. UVM_OBJ_KERN
65 * allows us to decide which type of unmapping we want to do.
66 */
67 #define UVM_OBJ_KERN (-2)
68
69 #define UVM_OBJ_IS_KERN_OBJECT(uobj) \
70 ((uobj)->uo_refs == UVM_OBJ_KERN)
71
72 #ifdef _KERNEL
73
74 extern const struct uvm_pagerops uvm_vnodeops;
75 extern const struct uvm_pagerops uvm_deviceops;
76 extern const struct uvm_pagerops ubc_pager;
77 extern const struct uvm_pagerops aobj_pager;
78
79 #define UVM_OBJ_IS_VNODE(uobj) \
80 ((uobj)->pgops == &uvm_vnodeops)
81
82 #define UVM_OBJ_IS_DEVICE(uobj) \
83 ((uobj)->pgops == &uvm_deviceops)
84
85 #define UVM_OBJ_IS_VTEXT(uobj) \
86 (UVM_OBJ_IS_VNODE(uobj) && uvn_text_p(uobj))
87
88 #define UVM_OBJ_IS_CLEAN(uobj) \
89 (UVM_OBJ_IS_VNODE(uobj) && uvn_clean_p(uobj))
90
91 /*
92 * UVM_OBJ_NEEDS_WRITEFAULT: true if the uobj needs to detect modification.
93 * (ie. wants to avoid writable user mappings.)
94 *
95 * XXX bad name
96 */
97
98 #define UVM_OBJ_NEEDS_WRITEFAULT(uobj) \
99 (UVM_OBJ_IS_VNODE(uobj) && uvn_needs_writefault_p(uobj))
100
101 #define UVM_OBJ_IS_AOBJ(uobj) \
102 ((uobj)->pgops == &aobj_pager)
103
104 extern const rb_tree_ops_t uvm_page_tree_ops;
105
106 #endif /* _KERNEL */
107
108 #endif /* _UVM_UVM_OBJECT_H_ */
109