xref: /freebsd/sys/vm/vm_unix.c (revision ee51cfe17ce50ca189c85280cbe3c3aa7b6dd7f9)
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   * 3. 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  	datalim = lim_cur(td, RLIMIT_DATA);
87  	lmemlim = lim_cur(td, RLIMIT_MEMLOCK);
88  	vmemlim = lim_cur(td, RLIMIT_VMEM);
89  
90  	do_map_wirefuture = FALSE;
91  	new = round_page((vm_offset_t)uap->nsize);
92  	vm_map_lock(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(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 (!old_mlock && map->flags & MAP_WIREFUTURE) {
120  			if (ptoa(pmap_wired_count(map->pmap)) +
121  			    (new - old) > lmemlim) {
122  				error = ENOMEM;
123  				goto done;
124  			}
125  		}
126  		if (map->size + (new - old) > vmemlim) {
127  			error = ENOMEM;
128  			goto done;
129  		}
130  #ifdef RACCT
131  		if (racct_enable) {
132  			PROC_LOCK(td->td_proc);
133  			error = racct_set(td->td_proc, RACCT_DATA, new - base);
134  			if (error != 0) {
135  				PROC_UNLOCK(td->td_proc);
136  				error = ENOMEM;
137  				goto done;
138  			}
139  			error = racct_set(td->td_proc, RACCT_VMEM,
140  			    map->size + (new - old));
141  			if (error != 0) {
142  				racct_set_force(td->td_proc, RACCT_DATA,
143  				    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)) +
151  				    (new - old));
152  				if (error != 0) {
153  					racct_set_force(td->td_proc, RACCT_DATA,
154  					    old - base);
155  					racct_set_force(td->td_proc, RACCT_VMEM,
156  					    map->size);
157  					PROC_UNLOCK(td->td_proc);
158  					error = ENOMEM;
159  					goto done;
160  				}
161  			}
162  			PROC_UNLOCK(td->td_proc);
163  		}
164  #endif
165  		prot = VM_PROT_RW;
166  #ifdef COMPAT_FREEBSD32
167  #if defined(__amd64__)
168  		if (i386_read_exec && SV_PROC_FLAG(td->td_proc, SV_ILP32))
169  			prot |= VM_PROT_EXECUTE;
170  #endif
171  #endif
172  		rv = vm_map_insert(map, NULL, 0, old, new, prot, VM_PROT_ALL, 0);
173  		if (rv != KERN_SUCCESS) {
174  #ifdef RACCT
175  			if (racct_enable) {
176  				PROC_LOCK(td->td_proc);
177  				racct_set_force(td->td_proc,
178  				    RACCT_DATA, old - base);
179  				racct_set_force(td->td_proc,
180  				    RACCT_VMEM, map->size);
181  				if (!old_mlock && map->flags & MAP_WIREFUTURE) {
182  					racct_set_force(td->td_proc,
183  					    RACCT_MEMLOCK,
184  					    ptoa(pmap_wired_count(map->pmap)));
185  				}
186  				PROC_UNLOCK(td->td_proc);
187  			}
188  #endif
189  			error = ENOMEM;
190  			goto done;
191  		}
192  		vm->vm_dsize += btoc(new - old);
193  		/*
194  		 * Handle the MAP_WIREFUTURE case for legacy applications,
195  		 * by marking the newly mapped range of pages as wired.
196  		 * We are not required to perform a corresponding
197  		 * vm_map_unwire() before vm_map_delete() below, as
198  		 * it will forcibly unwire the pages in the range.
199  		 *
200  		 * XXX If the pages cannot be wired, no error is returned.
201  		 */
202  		if ((map->flags & MAP_WIREFUTURE) == MAP_WIREFUTURE) {
203  			if (bootverbose)
204  				printf("obreak: MAP_WIREFUTURE set\n");
205  			do_map_wirefuture = TRUE;
206  		}
207  	} else if (new < old) {
208  		rv = vm_map_delete(map, new, old);
209  		if (rv != KERN_SUCCESS) {
210  			error = ENOMEM;
211  			goto done;
212  		}
213  		vm->vm_dsize -= btoc(old - new);
214  #ifdef RACCT
215  		if (racct_enable) {
216  			PROC_LOCK(td->td_proc);
217  			racct_set_force(td->td_proc, RACCT_DATA, new - base);
218  			racct_set_force(td->td_proc, RACCT_VMEM, map->size);
219  			if (!old_mlock && map->flags & MAP_WIREFUTURE) {
220  				racct_set_force(td->td_proc, RACCT_MEMLOCK,
221  				    ptoa(pmap_wired_count(map->pmap)));
222  			}
223  			PROC_UNLOCK(td->td_proc);
224  		}
225  #endif
226  	}
227  done:
228  	vm_map_unlock(map);
229  
230  	if (do_map_wirefuture)
231  		(void) vm_map_wire(map, old, new,
232  		    VM_MAP_WIRE_USER|VM_MAP_WIRE_NOHOLES);
233  
234  	return (error);
235  }
236  
237  #ifndef _SYS_SYSPROTO_H_
238  struct ovadvise_args {
239  	int anom;
240  };
241  #endif
242  
243  /*
244   * MPSAFE
245   */
246  /* ARGSUSED */
247  int
248  sys_ovadvise(td, uap)
249  	struct thread *td;
250  	struct ovadvise_args *uap;
251  {
252  	/* START_GIANT_OPTIONAL */
253  	/* END_GIANT_OPTIONAL */
254  	return (EINVAL);
255  }
256