xref: /netbsd-src/sys/uvm/uvm_unix.c (revision 1ffa7b76c40339c17a0fb2a09fac93f287cfc046)
1 /*	$NetBSD: uvm_unix.c,v 1.27 2003/01/18 09:43:02 thorpej Exp $	*/
2 
3 /*
4  * Copyright (c) 1997 Charles D. Cranor and Washington University.
5  * Copyright (c) 1991, 1993 The Regents of the University of California.
6  * Copyright (c) 1988 University of Utah.
7  *
8  * All rights reserved.
9  *
10  * This code is derived from software contributed to Berkeley by
11  * the Systems Programming Group of the University of Utah Computer
12  * Science Department.
13  *
14  * Redistribution and use in source and binary forms, with or without
15  * modification, are permitted provided that the following conditions
16  * are met:
17  * 1. Redistributions of source code must retain the above copyright
18  *    notice, this list of conditions and the following disclaimer.
19  * 2. Redistributions in binary form must reproduce the above copyright
20  *    notice, this list of conditions and the following disclaimer in the
21  *    documentation and/or other materials provided with the distribution.
22  * 3. All advertising materials mentioning features or use of this software
23  *    must display the following acknowledgement:
24  *      This product includes software developed by Charles D. Cranor,
25  *	Washington University, the University of California, Berkeley and
26  *	its contributors.
27  * 4. Neither the name of the University nor the names of its contributors
28  *    may be used to endorse or promote products derived from this software
29  *    without specific prior written permission.
30  *
31  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
32  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
33  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
34  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
35  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
39  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
40  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
41  * SUCH DAMAGE.
42  *
43  * from: Utah $Hdr: vm_unix.c 1.1 89/11/07$
44  *      @(#)vm_unix.c   8.1 (Berkeley) 6/11/93
45  * from: Id: uvm_unix.c,v 1.1.2.2 1997/08/25 18:52:30 chuck Exp
46  */
47 
48 /*
49  * uvm_unix.c: traditional sbrk/grow interface to vm.
50  */
51 
52 #include <sys/cdefs.h>
53 __KERNEL_RCSID(0, "$NetBSD: uvm_unix.c,v 1.27 2003/01/18 09:43:02 thorpej Exp $");
54 
55 #include <sys/param.h>
56 #include <sys/systm.h>
57 #include <sys/proc.h>
58 #include <sys/resourcevar.h>
59 #include <sys/vnode.h>
60 
61 #include <sys/mount.h>
62 #include <sys/sa.h>
63 #include <sys/syscallargs.h>
64 
65 #include <uvm/uvm.h>
66 
67 /*
68  * sys_obreak: set break
69  */
70 
71 int
72 sys_obreak(l, v, retval)
73 	struct lwp *l;
74 	void *v;
75 	register_t *retval;
76 {
77 	struct sys_obreak_args /* {
78 		syscallarg(char *) nsize;
79 	} */ *uap = v;
80 	struct proc *p = l->l_proc;
81 	struct vmspace *vm = p->p_vmspace;
82 	vaddr_t new, old;
83 	int error;
84 
85 	old = (vaddr_t)vm->vm_daddr;
86 	new = round_page((vaddr_t)SCARG(uap, nsize));
87 	if ((new - old) > p->p_rlimit[RLIMIT_DATA].rlim_cur && new > old)
88 		return (ENOMEM);
89 
90 	old = round_page(old + ptoa(vm->vm_dsize));
91 
92 	if (new == old)
93 		return (0);
94 
95 	/*
96 	 * grow or shrink?
97 	 */
98 	if (new > old) {
99 		error = uvm_map(&vm->vm_map, &old, new - old, NULL,
100 		    UVM_UNKNOWN_OFFSET, 0,
101 		    UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_COPY,
102 		    UVM_ADV_NORMAL, UVM_FLAG_AMAPPAD|UVM_FLAG_FIXED|
103 		    UVM_FLAG_OVERLAY|UVM_FLAG_COPYONW));
104 		if (error) {
105 			uprintf("sbrk: grow %ld failed, error = %d\n",
106 				new - old, error);
107 			return error;
108 		}
109 		vm->vm_dsize += atop(new - old);
110 	} else {
111 		uvm_deallocate(&vm->vm_map, new, old - new);
112 		vm->vm_dsize -= atop(old - new);
113 	}
114 	return 0;
115 }
116 
117 /*
118  * uvm_grow: enlarge the "stack segment" to include sp.
119  */
120 
121 int
122 uvm_grow(p, sp)
123 	struct proc *p;
124 	vaddr_t sp;
125 {
126 	struct vmspace *vm = p->p_vmspace;
127 	int si;
128 
129 	/*
130 	 * For user defined stacks (from sendsig).
131 	 */
132 	if (sp < (vaddr_t)vm->vm_maxsaddr)
133 		return (0);
134 
135 	/*
136 	 * For common case of already allocated (from trap).
137 	 */
138 	if (sp >= USRSTACK - ctob(vm->vm_ssize))
139 		return (1);
140 
141 	/*
142 	 * Really need to check vs limit and increment stack size if ok.
143 	 */
144 	si = btoc(USRSTACK-sp) - vm->vm_ssize;
145 	if (vm->vm_ssize + si > btoc(p->p_rlimit[RLIMIT_STACK].rlim_cur))
146 		return (0);
147 	vm->vm_ssize += si;
148 	return (1);
149 }
150 
151 /*
152  * sys_oadvise: old advice system call
153  */
154 
155 /* ARGSUSED */
156 int
157 sys_ovadvise(l, v, retval)
158 	struct lwp *l;
159 	void *v;
160 	register_t *retval;
161 {
162 #if 0
163 	struct sys_ovadvise_args /* {
164 		syscallarg(int) anom;
165 	} */ *uap = v;
166 #endif
167 
168 	return (EINVAL);
169 }
170