xref: /openbsd-src/sys/uvm/uvm_unix.c (revision 47911bd667ac77dc523b8a13ef40b012dbffa741)
1 /*	$OpenBSD: uvm_unix.c,v 1.22 2002/10/29 18:30:21 art Exp $	*/
2 /*	$NetBSD: uvm_unix.c,v 1.18 2000/09/13 15:00:25 thorpej Exp $	*/
3 
4 /*
5  * Copyright (c) 1997 Charles D. Cranor and Washington University.
6  * Copyright (c) 1991, 1993 The Regents of the University of California.
7  * Copyright (c) 1988 University of Utah.
8  *
9  * All rights reserved.
10  *
11  * This code is derived from software contributed to Berkeley by
12  * the Systems Programming Group of the University of Utah Computer
13  * Science Department.
14  *
15  * Redistribution and use in source and binary forms, with or without
16  * modification, are permitted provided that the following conditions
17  * are met:
18  * 1. Redistributions of source code must retain the above copyright
19  *    notice, this list of conditions and the following disclaimer.
20  * 2. Redistributions in binary form must reproduce the above copyright
21  *    notice, this list of conditions and the following disclaimer in the
22  *    documentation and/or other materials provided with the distribution.
23  * 3. All advertising materials mentioning features or use of this software
24  *    must display the following acknowledgement:
25  *      This product includes software developed by Charles D. Cranor,
26  *	Washington University, the University of California, Berkeley and
27  *	its contributors.
28  * 4. Neither the name of the University nor the names of its contributors
29  *    may be used to endorse or promote products derived from this software
30  *    without specific prior written permission.
31  *
32  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
33  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
34  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
35  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
36  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
37  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
38  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
39  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
40  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
41  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
42  * SUCH DAMAGE.
43  *
44  * from: Utah $Hdr: vm_unix.c 1.1 89/11/07$
45  *      @(#)vm_unix.c   8.1 (Berkeley) 6/11/93
46  * from: Id: uvm_unix.c,v 1.1.2.2 1997/08/25 18:52:30 chuck Exp
47  */
48 
49 /*
50  * uvm_unix.c: traditional sbrk/grow interface to vm.
51  */
52 
53 #include <sys/param.h>
54 #include <sys/systm.h>
55 #include <sys/proc.h>
56 #include <sys/resourcevar.h>
57 #include <sys/vnode.h>
58 #include <sys/core.h>
59 
60 #include <sys/mount.h>
61 #include <sys/syscallargs.h>
62 
63 #include <uvm/uvm.h>
64 
65 /*
66  * sys_obreak: set break
67  */
68 
69 int
70 sys_obreak(p, v, retval)
71 	struct proc *p;
72 	void *v;
73 	register_t *retval;
74 {
75 	struct sys_obreak_args /* {
76 		syscallarg(char *) nsize;
77 	} */ *uap = v;
78 	struct vmspace *vm = p->p_vmspace;
79 	vaddr_t new, old;
80 	int error;
81 
82 	old = (vaddr_t)vm->vm_daddr;
83 	new = round_page((vaddr_t)SCARG(uap, nsize));
84 	if ((new - old) > p->p_rlimit[RLIMIT_DATA].rlim_cur)
85 		return (ENOMEM);
86 
87 	old = round_page(old + ptoa(vm->vm_dsize));
88 
89 	if (new == old)
90 		return (0);
91 
92 	/*
93 	 * grow or shrink?
94 	 */
95 	if (new > old) {
96 		error = uvm_map(&vm->vm_map, &old, new - old, NULL,
97 		    UVM_UNKNOWN_OFFSET, 0,
98 		    UVM_MAPFLAG(UVM_PROT_RW, UVM_PROT_RWX, UVM_INH_COPY,
99 		    UVM_ADV_NORMAL, UVM_FLAG_AMAPPAD|UVM_FLAG_FIXED|
100 		    UVM_FLAG_OVERLAY|UVM_FLAG_COPYONW));
101 		if (error) {
102 			uprintf("sbrk: grow %ld failed, error = %d\n",
103 			    new - old, error);
104 			return (ENOMEM);
105 		}
106 		vm->vm_dsize += atop(new - old);
107 	} else {
108 		uvm_deallocate(&vm->vm_map, new, old - new);
109 		vm->vm_dsize -= atop(old - new);
110 	}
111 
112 	return (0);
113 }
114 
115 /*
116  * uvm_grow: enlarge the "stack segment" to include sp.
117  */
118 
119 int
120 uvm_grow(p, sp)
121 	struct proc *p;
122 	vaddr_t sp;
123 {
124 	struct vmspace *vm = p->p_vmspace;
125 	int si;
126 
127 	/*
128 	 * For user defined stacks (from sendsig).
129 	 */
130 #ifdef MACHINE_STACK_GROWS_UP
131 	if (sp > (vaddr_t)vm->vm_maxsaddr)
132 #else
133 	if (sp < (vaddr_t)vm->vm_maxsaddr)
134 #endif
135 		return (0);
136 
137 	/*
138 	 * For common case of already allocated (from trap).
139 	 */
140 #ifdef MACHINE_STACK_GROWS_UP
141 	if (sp < USRSTACK + ctob(vm->vm_ssize))
142 #else
143 	if (sp >= USRSTACK - ctob(vm->vm_ssize))
144 #endif
145 		return (1);
146 
147 	/*
148 	 * Really need to check vs limit and increment stack size if ok.
149 	 */
150 #ifdef MACHINE_STACK_GROWS_UP
151 	si = btoc(sp - USRSTACK) - vm->vm_ssize;
152 #else
153 	si = btoc(USRSTACK-sp) - vm->vm_ssize;
154 #endif
155 	if (vm->vm_ssize + si > btoc(p->p_rlimit[RLIMIT_STACK].rlim_cur))
156 		return (0);
157 	vm->vm_ssize += si;
158 	return (1);
159 }
160 
161 /*
162  * sys_oadvise: old advice system call
163  */
164 
165 /* ARGSUSED */
166 int
167 sys_ovadvise(p, v, retval)
168 	struct proc *p;
169 	void *v;
170 	register_t *retval;
171 {
172 #if 0
173 	struct sys_ovadvise_args /* {
174 		syscallarg(int) anom;
175 	} */ *uap = v;
176 #endif
177 
178 	return (EINVAL);
179 }
180 
181 /*
182  * uvm_coredump: dump core!
183  */
184 
185 int
186 uvm_coredump(p, vp, cred, chdr)
187 	struct proc *p;
188 	struct vnode *vp;
189 	struct ucred *cred;
190 	struct core *chdr;
191 {
192 	struct vmspace *vm = p->p_vmspace;
193 	vm_map_t map = &vm->vm_map;
194 	vm_map_entry_t entry;
195 	vaddr_t start, end, maxstack;
196 	struct coreseg cseg;
197 	off_t offset;
198 	int flag, error = 0;
199 
200 	offset = chdr->c_hdrsize + chdr->c_seghdrsize + chdr->c_cpusize;
201 	maxstack = trunc_page(USRSTACK - ctob(vm->vm_ssize));
202 
203 	for (entry = map->header.next; entry != &map->header;
204 	    entry = entry->next) {
205 
206 		/* should never happen for a user process */
207 		if (UVM_ET_ISSUBMAP(entry)) {
208 			panic("uvm_coredump: user process with submap?");
209 		}
210 
211 		if (!(entry->protection & VM_PROT_WRITE))
212 			continue;
213 
214 		start = entry->start;
215 		end = entry->end;
216 
217 		if (start >= VM_MAXUSER_ADDRESS)
218 			continue;
219 
220 		if (end > VM_MAXUSER_ADDRESS)
221 			end = VM_MAXUSER_ADDRESS;
222 
223 #ifdef MACHINE_STACK_GROWS_UP
224 		if (start >= USRSTACK) {
225 			start = USRSTACK;
226 #else
227 		if (start >= (vaddr_t)vm->vm_maxsaddr) {
228 			start = trunc_page(USRSTACK - ctob(vm->vm_ssize));
229 #endif
230 			flag = CORE_STACK;
231 			if (start >= end)
232 				continue;
233 		} else
234 			flag = CORE_DATA;
235 
236 		/*
237 		 * Set up a new core file segment.
238 		 */
239 		CORE_SETMAGIC(cseg, CORESEGMAGIC, CORE_GETMID(*chdr), flag);
240 		cseg.c_addr = start;
241 		cseg.c_size = end - start;
242 
243 		error = vn_rdwr(UIO_WRITE, vp,
244 		    (caddr_t)&cseg, chdr->c_seghdrsize,
245 		    offset, UIO_SYSSPACE,
246 		    IO_NODELOCKED|IO_UNIT, cred, NULL, p);
247 		if (error)
248 			break;
249 
250 		offset += chdr->c_seghdrsize;
251 		error = vn_rdwr(UIO_WRITE, vp,
252 		    (caddr_t)(u_long)cseg.c_addr, (int)cseg.c_size,
253 		    offset, UIO_USERSPACE,
254 		    IO_NODELOCKED|IO_UNIT, cred, NULL, p);
255 		if (error)
256 			break;
257 
258 		offset += cseg.c_size;
259 		chdr->c_nseg++;
260 	}
261 
262 	return (error);
263 }
264 
265