xref: /openbsd/sys/uvm/uvm_vnode.h (revision a6445c1d)
1 /*	$OpenBSD: uvm_vnode.h,v 1.13 2014/06/29 22:56:31 deraadt Exp $	*/
2 /*	$NetBSD: uvm_vnode.h,v 1.9 2000/03/26 20:54:48 kleink Exp $	*/
3 
4 /*
5  *
6  * Copyright (c) 1997 Charles D. Cranor and Washington University.
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *      This product includes software developed by Charles D. Cranor and
20  *      Washington University.
21  * 4. The name of the author may not be used to endorse or promote products
22  *    derived from this software without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
25  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
26  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
27  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
28  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
29  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
30  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
31  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
32  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
33  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34  *
35  * from: Id: uvm_vnode.h,v 1.1.2.4 1997/10/03 21:18:24 chuck Exp
36  */
37 
38 #ifndef _UVM_UVM_VNODE_H_
39 #define _UVM_UVM_VNODE_H_
40 
41 /*
42  * uvm_vnode.h
43  *
44  * vnode handle into the VM system.
45  */
46 
47 /*
48  * the uvm_vnode structure.   put at the top of the vnode data structure.
49  * this allows:
50  *   (struct vnode *) == (struct uvm_vnode *) == (struct uvm_object *)
51  */
52 
53 struct uvm_vnode {
54 	struct uvm_object u_obj;	/* the actual VM object */
55 	int u_flags;			/* flags */
56 	int u_nio;			/* number of running I/O requests */
57 	voff_t u_size;			/* size of object */
58 
59 	/* the following entry is locked by uvn_wl_lock */
60 	LIST_ENTRY(uvm_vnode) u_wlist;	/* list of writeable vnode objects */
61 
62 	/* the following entry is locked by uvn_sync_lock */
63 	SIMPLEQ_ENTRY(uvm_vnode) u_syncq; /* vnode objects due for a "sync" */
64 };
65 
66 /*
67  * u_flags values
68  */
69 #define UVM_VNODE_VALID		0x001	/* we are attached to the vnode */
70 #define UVM_VNODE_CANPERSIST	0x002	/* we can persist after ref == 0 */
71 #define UVM_VNODE_ALOCK		0x004	/* uvn_attach is locked out */
72 #define UVM_VNODE_DYING		0x008	/* final detach/terminate in
73 					   progress */
74 #define UVM_VNODE_RELKILL	0x010	/* uvn should be killed by releasepg
75 					   when final i/o is done */
76 #define UVM_VNODE_WANTED	0x020	/* someone is waiting for alock,
77 					   dying, or relkill to clear */
78 #define UVM_VNODE_VNISLOCKED	0x040	/* underlying vnode struct is locked
79 					   (valid when DYING is true) */
80 #define UVM_VNODE_IOSYNC	0x080	/* I/O sync in progress ... setter
81 					   sleeps on &uvn->u_nio */
82 #define UVM_VNODE_IOSYNCWANTED	0x100	/* a process is waiting for the
83 					   i/o sync to clear so it can do
84 					   i/o */
85 #define UVM_VNODE_WRITEABLE	0x200	/* uvn has pages that are writeable */
86 
87 /*
88  * UVM_VNODE_BLOCKED: any condition that should new processes from
89  * touching the vnode [set WANTED and sleep to wait for it to clear]
90  */
91 #define UVM_VNODE_BLOCKED (UVM_VNODE_ALOCK|UVM_VNODE_DYING|UVM_VNODE_RELKILL)
92 
93 #endif /* _UVM_UVM_VNODE_H_ */
94