xref: /freebsd/sys/vm/vm_unix.c (revision 40a8ac8f62b535d30349faf28cf47106b7041b83)
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_map_t map = &vm->vm_map;
80 	vm_offset_t new, old, base;
81 	rlim_t datalim, lmemlim, vmemlim;
82 	int prot, rv;
83 	int error = 0;
84 	boolean_t do_map_wirefuture;
85 
86 	PROC_LOCK(td->td_proc);
87 	datalim = lim_cur(td->td_proc, RLIMIT_DATA);
88 	lmemlim = lim_cur(td->td_proc, RLIMIT_MEMLOCK);
89 	vmemlim = lim_cur(td->td_proc, RLIMIT_VMEM);
90 	PROC_UNLOCK(td->td_proc);
91 
92 	do_map_wirefuture = FALSE;
93 	new = round_page((vm_offset_t)uap->nsize);
94 	vm_map_lock(map);
95 
96 	base = round_page((vm_offset_t) vm->vm_daddr);
97 	old = base + ctob(vm->vm_dsize);
98 	if (new > base) {
99 		/*
100 		 * Check the resource limit, but allow a process to reduce
101 		 * its usage, even if it remains over the limit.
102 		 */
103 		if (new - base > datalim && new > old) {
104 			error = ENOMEM;
105 			goto done;
106 		}
107 		if (new > vm_map_max(map)) {
108 			error = ENOMEM;
109 			goto done;
110 		}
111 	} else if (new < base) {
112 		/*
113 		 * This is simply an invalid value.  If someone wants to
114 		 * do fancy address space manipulations, mmap and munmap
115 		 * can do most of what the user would want.
116 		 */
117 		error = EINVAL;
118 		goto done;
119 	}
120 	if (new > old) {
121 		if (!old_mlock && map->flags & MAP_WIREFUTURE) {
122 			if (ptoa(pmap_wired_count(map->pmap)) +
123 			    (new - old) > lmemlim) {
124 				error = ENOMEM;
125 				goto done;
126 			}
127 		}
128 		if (map->size + (new - old) > vmemlim) {
129 			error = ENOMEM;
130 			goto done;
131 		}
132 #ifdef RACCT
133 		PROC_LOCK(td->td_proc);
134 		error = racct_set(td->td_proc, RACCT_DATA, new - base);
135 		if (error != 0) {
136 			PROC_UNLOCK(td->td_proc);
137 			error = ENOMEM;
138 			goto done;
139 		}
140 		error = racct_set(td->td_proc, RACCT_VMEM,
141 		    map->size + (new - old));
142 		if (error != 0) {
143 			racct_set_force(td->td_proc, RACCT_DATA, old - base);
144 			PROC_UNLOCK(td->td_proc);
145 			error = ENOMEM;
146 			goto done;
147 		}
148 		if (!old_mlock && map->flags & MAP_WIREFUTURE) {
149 			error = racct_set(td->td_proc, RACCT_MEMLOCK,
150 			    ptoa(pmap_wired_count(map->pmap)) + (new - old));
151 			if (error != 0) {
152 				racct_set_force(td->td_proc, RACCT_DATA,
153 				    old - base);
154 				racct_set_force(td->td_proc, RACCT_VMEM,
155 				    map->size);
156 				PROC_UNLOCK(td->td_proc);
157 				error = ENOMEM;
158 				goto done;
159 			}
160 		}
161 		PROC_UNLOCK(td->td_proc);
162 #endif
163 		prot = VM_PROT_RW;
164 #ifdef COMPAT_FREEBSD32
165 #if defined(__amd64__)
166 		if (i386_read_exec && SV_PROC_FLAG(td->td_proc, SV_ILP32))
167 			prot |= VM_PROT_EXECUTE;
168 #endif
169 #endif
170 		rv = vm_map_insert(map, NULL, 0, old, new, prot, VM_PROT_ALL, 0);
171 		if (rv != KERN_SUCCESS) {
172 #ifdef RACCT
173 			PROC_LOCK(td->td_proc);
174 			racct_set_force(td->td_proc, RACCT_DATA, old - base);
175 			racct_set_force(td->td_proc, RACCT_VMEM, map->size);
176 			if (!old_mlock && map->flags & MAP_WIREFUTURE) {
177 				racct_set_force(td->td_proc, RACCT_MEMLOCK,
178 				    ptoa(pmap_wired_count(map->pmap)));
179 			}
180 			PROC_UNLOCK(td->td_proc);
181 #endif
182 			error = ENOMEM;
183 			goto done;
184 		}
185 		vm->vm_dsize += btoc(new - old);
186 		/*
187 		 * Handle the MAP_WIREFUTURE case for legacy applications,
188 		 * by marking the newly mapped range of pages as wired.
189 		 * We are not required to perform a corresponding
190 		 * vm_map_unwire() before vm_map_delete() below, as
191 		 * it will forcibly unwire the pages in the range.
192 		 *
193 		 * XXX If the pages cannot be wired, no error is returned.
194 		 */
195 		if ((map->flags & MAP_WIREFUTURE) == MAP_WIREFUTURE) {
196 			if (bootverbose)
197 				printf("obreak: MAP_WIREFUTURE set\n");
198 			do_map_wirefuture = TRUE;
199 		}
200 	} else if (new < old) {
201 		rv = vm_map_delete(map, new, old);
202 		if (rv != KERN_SUCCESS) {
203 			error = ENOMEM;
204 			goto done;
205 		}
206 		vm->vm_dsize -= btoc(old - new);
207 #ifdef RACCT
208 		PROC_LOCK(td->td_proc);
209 		racct_set_force(td->td_proc, RACCT_DATA, new - base);
210 		racct_set_force(td->td_proc, RACCT_VMEM, map->size);
211 		if (!old_mlock && map->flags & MAP_WIREFUTURE) {
212 			racct_set_force(td->td_proc, RACCT_MEMLOCK,
213 			    ptoa(pmap_wired_count(map->pmap)));
214 		}
215 		PROC_UNLOCK(td->td_proc);
216 #endif
217 	}
218 done:
219 	vm_map_unlock(map);
220 
221 	if (do_map_wirefuture)
222 		(void) vm_map_wire(map, old, new,
223 		    VM_MAP_WIRE_USER|VM_MAP_WIRE_NOHOLES);
224 
225 	return (error);
226 }
227 
228 #ifndef _SYS_SYSPROTO_H_
229 struct ovadvise_args {
230 	int anom;
231 };
232 #endif
233 
234 /*
235  * MPSAFE
236  */
237 /* ARGSUSED */
238 int
239 sys_ovadvise(td, uap)
240 	struct thread *td;
241 	struct ovadvise_args *uap;
242 {
243 	/* START_GIANT_OPTIONAL */
244 	/* END_GIANT_OPTIONAL */
245 	return (EINVAL);
246 }
247