xref: /openbsd-src/sys/uvm/uvm_unix.c (revision ce7e0fc6a9d74d25b78fb6ad846387717f5172b6)
1 /*	$OpenBSD: uvm_unix.c,v 1.20 2001/12/19 08:58:07 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 	ssize_t diff;
81 	int rv;
82 
83 	old = (vaddr_t)vm->vm_daddr;
84 	new = round_page((vaddr_t)SCARG(uap, nsize));
85 	if ((new - old) > p->p_rlimit[RLIMIT_DATA].rlim_cur)
86 		return (ENOMEM);
87 
88 	old = round_page(old + ptoa(vm->vm_dsize));
89 	diff = new - old;
90 
91 	if (diff == 0)
92 		return (0);
93 
94 	/*
95 	 * grow or shrink?
96 	 */
97 	if (diff > 0) {
98 		rv = uvm_map(&vm->vm_map, &old, diff, NULL, UVM_UNKNOWN_OFFSET,
99 		    0, UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_COPY,
100 		    UVM_ADV_NORMAL, UVM_FLAG_AMAPPAD|UVM_FLAG_FIXED|
101 		    UVM_FLAG_OVERLAY|UVM_FLAG_COPYONW));
102 		if (rv == KERN_SUCCESS) {
103 			vm->vm_dsize += atop(diff);
104 			return (0);
105 		}
106 	} else {
107 		rv = uvm_deallocate(&vm->vm_map, new, -diff);
108 		if (rv == KERN_SUCCESS) {
109 			vm->vm_dsize -= atop(-diff);
110 			return (0);
111 		}
112 	}
113 
114 	uprintf("sbrk: %s %ld failed, return = %d\n",
115 	    diff > 0 ? "grow" : "shrink",
116 	    (long)(diff > 0 ? diff : -diff), rv);
117 	return (ENOMEM);
118 }
119 
120 /*
121  * uvm_grow: enlarge the "stack segment" to include sp.
122  */
123 
124 int
125 uvm_grow(p, sp)
126 	struct proc *p;
127 	vaddr_t sp;
128 {
129 	struct vmspace *vm = p->p_vmspace;
130 	int si;
131 
132 	/*
133 	 * For user defined stacks (from sendsig).
134 	 */
135 #ifdef MACHINE_STACK_GROWS_UP
136 	if (sp > (vaddr_t)vm->vm_maxsaddr)
137 #else
138 	if (sp < (vaddr_t)vm->vm_maxsaddr)
139 #endif
140 		return (0);
141 
142 	/*
143 	 * For common case of already allocated (from trap).
144 	 */
145 #ifdef MACHINE_STACK_GROWS_UP
146 	if (sp < USRSTACK + ctob(vm->vm_ssize))
147 #else
148 	if (sp >= USRSTACK - ctob(vm->vm_ssize))
149 #endif
150 		return (1);
151 
152 	/*
153 	 * Really need to check vs limit and increment stack size if ok.
154 	 */
155 #ifdef MACHINE_STACK_GROWS_UP
156 	si = btoc(sp - USRSTACK) - vm->vm_ssize;
157 #else
158 	si = btoc(USRSTACK-sp) - vm->vm_ssize;
159 #endif
160 	if (vm->vm_ssize + si > btoc(p->p_rlimit[RLIMIT_STACK].rlim_cur))
161 		return (0);
162 	vm->vm_ssize += si;
163 	return (1);
164 }
165 
166 /*
167  * sys_oadvise: old advice system call
168  */
169 
170 /* ARGSUSED */
171 int
172 sys_ovadvise(p, v, retval)
173 	struct proc *p;
174 	void *v;
175 	register_t *retval;
176 {
177 #if 0
178 	struct sys_ovadvise_args /* {
179 		syscallarg(int) anom;
180 	} */ *uap = v;
181 #endif
182 
183 	return (EINVAL);
184 }
185 
186 /*
187  * uvm_coredump: dump core!
188  */
189 
190 int
191 uvm_coredump(p, vp, cred, chdr)
192 	struct proc *p;
193 	struct vnode *vp;
194 	struct ucred *cred;
195 	struct core *chdr;
196 {
197 	struct vmspace *vm = p->p_vmspace;
198 	vm_map_t map = &vm->vm_map;
199 	vm_map_entry_t entry;
200 	vaddr_t start, end, maxstack;
201 	struct coreseg cseg;
202 	off_t offset;
203 	int flag, error = 0;
204 
205 	offset = chdr->c_hdrsize + chdr->c_seghdrsize + chdr->c_cpusize;
206 	maxstack = trunc_page(USRSTACK - ctob(vm->vm_ssize));
207 
208 	for (entry = map->header.next; entry != &map->header;
209 	    entry = entry->next) {
210 
211 		/* should never happen for a user process */
212 		if (UVM_ET_ISSUBMAP(entry)) {
213 			panic("uvm_coredump: user process with submap?");
214 		}
215 
216 		if (!(entry->protection & VM_PROT_WRITE))
217 			continue;
218 
219 		start = entry->start;
220 		end = entry->end;
221 
222 		if (start >= VM_MAXUSER_ADDRESS)
223 			continue;
224 
225 		if (end > VM_MAXUSER_ADDRESS)
226 			end = VM_MAXUSER_ADDRESS;
227 
228 #ifdef MACHINE_STACK_GROWS_UP
229 		if (start >= USRSTACK) {
230 			start = USRSTACK;
231 #else
232 		if (start >= (vaddr_t)vm->vm_maxsaddr) {
233 			start = trunc_page(USRSTACK - ctob(vm->vm_ssize));
234 #endif
235 			flag = CORE_STACK;
236 			if (start >= end)
237 				continue;
238 		} else
239 			flag = CORE_DATA;
240 
241 		/*
242 		 * Set up a new core file segment.
243 		 */
244 		CORE_SETMAGIC(cseg, CORESEGMAGIC, CORE_GETMID(*chdr), flag);
245 		cseg.c_addr = start;
246 		cseg.c_size = end - start;
247 
248 		error = vn_rdwr(UIO_WRITE, vp,
249 		    (caddr_t)&cseg, chdr->c_seghdrsize,
250 		    offset, UIO_SYSSPACE,
251 		    IO_NODELOCKED|IO_UNIT, cred, NULL, p);
252 		if (error)
253 			break;
254 
255 		offset += chdr->c_seghdrsize;
256 		error = vn_rdwr(UIO_WRITE, vp,
257 		    (caddr_t)(u_long)cseg.c_addr, (int)cseg.c_size,
258 		    offset, UIO_USERSPACE,
259 		    IO_NODELOCKED|IO_UNIT, cred, NULL, p);
260 		if (error)
261 			break;
262 
263 		offset += cseg.c_size;
264 		chdr->c_nseg++;
265 	}
266 
267 	return (error);
268 }
269 
270