xref: /freebsd/sys/vm/vm_unix.c (revision 641a6cfb86023499caafe26a4d821a0b885cf00b)
1 /*-
2  * Copyright (c) 1988 University of Utah.
3  * Copyright (c) 1991, 1993
4  *	The Regents of the University of California.  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  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 4. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  * from: Utah $Hdr: vm_unix.c 1.1 89/11/07$
35  *
36  *	@(#)vm_unix.c	8.1 (Berkeley) 6/11/93
37  */
38 
39 #include "opt_compat.h"
40 
41 /*
42  * Traditional sbrk/grow interface to VM
43  */
44 
45 #include <sys/cdefs.h>
46 __FBSDID("$FreeBSD$");
47 
48 #include <sys/param.h>
49 #include <sys/lock.h>
50 #include <sys/mutex.h>
51 #include <sys/proc.h>
52 #include <sys/racct.h>
53 #include <sys/resourcevar.h>
54 #include <sys/sysent.h>
55 #include <sys/sysproto.h>
56 #include <sys/systm.h>
57 
58 #include <vm/vm.h>
59 #include <vm/vm_param.h>
60 #include <vm/pmap.h>
61 #include <vm/vm_map.h>
62 
63 #ifndef _SYS_SYSPROTO_H_
64 struct obreak_args {
65 	char *nsize;
66 };
67 #endif
68 
69 /*
70  * MPSAFE
71  */
72 /* ARGSUSED */
73 int
74 sys_obreak(td, uap)
75 	struct thread *td;
76 	struct obreak_args *uap;
77 {
78 	struct vmspace *vm = td->td_proc->p_vmspace;
79 	vm_offset_t new, old, base;
80 	rlim_t datalim, vmemlim;
81 	int prot, rv;
82 	int error = 0;
83 	boolean_t do_map_wirefuture;
84 
85 	PROC_LOCK(td->td_proc);
86 	datalim = lim_cur(td->td_proc, RLIMIT_DATA);
87 	vmemlim = lim_cur(td->td_proc, RLIMIT_VMEM);
88 	PROC_UNLOCK(td->td_proc);
89 
90 	do_map_wirefuture = FALSE;
91 	new = round_page((vm_offset_t)uap->nsize);
92 	vm_map_lock(&vm->vm_map);
93 
94 	base = round_page((vm_offset_t) vm->vm_daddr);
95 	old = base + ctob(vm->vm_dsize);
96 	if (new > base) {
97 		/*
98 		 * Check the resource limit, but allow a process to reduce
99 		 * its usage, even if it remains over the limit.
100 		 */
101 		if (new - base > datalim && new > old) {
102 			error = ENOMEM;
103 			goto done;
104 		}
105 		if (new > vm_map_max(&vm->vm_map)) {
106 			error = ENOMEM;
107 			goto done;
108 		}
109 	} else if (new < base) {
110 		/*
111 		 * This is simply an invalid value.  If someone wants to
112 		 * do fancy address space manipulations, mmap and munmap
113 		 * can do most of what the user would want.
114 		 */
115 		error = EINVAL;
116 		goto done;
117 	}
118 	if (new > old) {
119 		if (vm->vm_map.size + (new - old) > vmemlim) {
120 			error = ENOMEM;
121 			goto done;
122 		}
123 #ifdef RACCT
124 		PROC_LOCK(td->td_proc);
125 		error = racct_set(td->td_proc, RACCT_DATA, new - base);
126 		if (error != 0) {
127 			PROC_UNLOCK(td->td_proc);
128 			error = ENOMEM;
129 			goto done;
130 		}
131 		error = racct_set(td->td_proc, RACCT_VMEM,
132 		    vm->vm_map.size + (new - old));
133 		if (error != 0) {
134 			racct_set_force(td->td_proc, RACCT_DATA, old - base);
135 			PROC_UNLOCK(td->td_proc);
136 			error = ENOMEM;
137 			goto done;
138 		}
139 		PROC_UNLOCK(td->td_proc);
140 #endif
141 		prot = VM_PROT_RW;
142 #ifdef COMPAT_FREEBSD32
143 #if defined(__amd64__) || defined(__ia64__)
144 		if (i386_read_exec && SV_PROC_FLAG(td->td_proc, SV_ILP32))
145 			prot |= VM_PROT_EXECUTE;
146 #endif
147 #endif
148 		rv = vm_map_insert(&vm->vm_map, NULL, 0, old, new,
149 		    prot, VM_PROT_ALL, 0);
150 		if (rv != KERN_SUCCESS) {
151 #ifdef RACCT
152 			PROC_LOCK(td->td_proc);
153 			racct_set_force(td->td_proc, RACCT_DATA, old - base);
154 			racct_set_force(td->td_proc, RACCT_VMEM, vm->vm_map.size);
155 			PROC_UNLOCK(td->td_proc);
156 #endif
157 			error = ENOMEM;
158 			goto done;
159 		}
160 		vm->vm_dsize += btoc(new - old);
161 		/*
162 		 * Handle the MAP_WIREFUTURE case for legacy applications,
163 		 * by marking the newly mapped range of pages as wired.
164 		 * We are not required to perform a corresponding
165 		 * vm_map_unwire() before vm_map_delete() below, as
166 		 * it will forcibly unwire the pages in the range.
167 		 *
168 		 * XXX If the pages cannot be wired, no error is returned.
169 		 */
170 		if ((vm->vm_map.flags & MAP_WIREFUTURE) == MAP_WIREFUTURE) {
171 			if (bootverbose)
172 				printf("obreak: MAP_WIREFUTURE set\n");
173 			do_map_wirefuture = TRUE;
174 		}
175 	} else if (new < old) {
176 		rv = vm_map_delete(&vm->vm_map, new, old);
177 		if (rv != KERN_SUCCESS) {
178 			error = ENOMEM;
179 			goto done;
180 		}
181 		vm->vm_dsize -= btoc(old - new);
182 #ifdef RACCT
183 		PROC_LOCK(td->td_proc);
184 		racct_set_force(td->td_proc, RACCT_DATA, new - base);
185 		racct_set_force(td->td_proc, RACCT_VMEM, vm->vm_map.size);
186 		PROC_UNLOCK(td->td_proc);
187 #endif
188 	}
189 done:
190 	vm_map_unlock(&vm->vm_map);
191 
192 	if (do_map_wirefuture)
193 		(void) vm_map_wire(&vm->vm_map, old, new,
194 		    VM_MAP_WIRE_USER|VM_MAP_WIRE_NOHOLES);
195 
196 	return (error);
197 }
198 
199 #ifndef _SYS_SYSPROTO_H_
200 struct ovadvise_args {
201 	int anom;
202 };
203 #endif
204 
205 /*
206  * MPSAFE
207  */
208 /* ARGSUSED */
209 int
210 sys_ovadvise(td, uap)
211 	struct thread *td;
212 	struct ovadvise_args *uap;
213 {
214 	/* START_GIANT_OPTIONAL */
215 	/* END_GIANT_OPTIONAL */
216 	return (EINVAL);
217 }
218