1 | /* $NetBSD: uvm_unix.c,v 1.47 2016/04/07 12:07:36 christos Exp $ */ |
2 | |
3 | /* |
4 | * Copyright (c) 1997 Charles D. Cranor and Washington University. |
5 | * Copyright (c) 1991, 1993 The Regents of the University of California. |
6 | * Copyright (c) 1988 University of Utah. |
7 | * |
8 | * All rights reserved. |
9 | * |
10 | * This code is derived from software contributed to Berkeley by |
11 | * the Systems Programming Group of the University of Utah Computer |
12 | * Science Department. |
13 | * |
14 | * Redistribution and use in source and binary forms, with or without |
15 | * modification, are permitted provided that the following conditions |
16 | * are met: |
17 | * 1. Redistributions of source code must retain the above copyright |
18 | * notice, this list of conditions and the following disclaimer. |
19 | * 2. Redistributions in binary form must reproduce the above copyright |
20 | * notice, this list of conditions and the following disclaimer in the |
21 | * documentation and/or other materials provided with the distribution. |
22 | * 3. Neither the name of the University nor the names of its contributors |
23 | * may be used to endorse or promote products derived from this software |
24 | * without specific prior written permission. |
25 | * |
26 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
27 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
28 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
29 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
30 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
31 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
32 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
33 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
34 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
35 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
36 | * SUCH DAMAGE. |
37 | * |
38 | * from: Utah $Hdr: vm_unix.c 1.1 89/11/07$ |
39 | * @(#)vm_unix.c 8.1 (Berkeley) 6/11/93 |
40 | * from: Id: uvm_unix.c,v 1.1.2.2 1997/08/25 18:52:30 chuck Exp |
41 | */ |
42 | |
43 | /* |
44 | * uvm_unix.c: traditional sbrk/grow interface to vm. |
45 | */ |
46 | |
47 | #include <sys/cdefs.h> |
48 | __KERNEL_RCSID(0, "$NetBSD: uvm_unix.c,v 1.47 2016/04/07 12:07:36 christos Exp $" ); |
49 | |
50 | #include "opt_pax.h" |
51 | |
52 | #include <sys/param.h> |
53 | #include <sys/systm.h> |
54 | #include <sys/proc.h> |
55 | #include <sys/resourcevar.h> |
56 | |
57 | #include <sys/mount.h> |
58 | #include <sys/syscallargs.h> |
59 | #include <sys/pax.h> |
60 | |
61 | #include <uvm/uvm.h> |
62 | |
63 | /* |
64 | * sys_obreak: set break |
65 | */ |
66 | |
67 | int |
68 | sys_obreak(struct lwp *l, const struct sys_obreak_args *uap, register_t *retval) |
69 | { |
70 | /* { |
71 | syscallarg(char *) nsize; |
72 | } */ |
73 | struct proc *p = l->l_proc; |
74 | struct vmspace *vm = p->p_vmspace; |
75 | vaddr_t nbreak, obreak; |
76 | int error; |
77 | |
78 | mutex_enter(&p->p_auxlock); |
79 | obreak = (vaddr_t)vm->vm_daddr; |
80 | nbreak = round_page((vaddr_t)SCARG(uap, nsize)); |
81 | if (nbreak == 0 |
82 | || ((nbreak - obreak) > p->p_rlimit[RLIMIT_DATA].rlim_cur |
83 | && nbreak > obreak)) { |
84 | mutex_exit(&p->p_auxlock); |
85 | return (ENOMEM); |
86 | } |
87 | |
88 | obreak = round_page(obreak + ptoa(vm->vm_dsize)); |
89 | |
90 | if (nbreak == obreak) { |
91 | mutex_exit(&p->p_auxlock); |
92 | return (0); |
93 | } |
94 | |
95 | /* |
96 | * grow or shrink? |
97 | */ |
98 | |
99 | if (nbreak > obreak) { |
100 | vm_prot_t prot = UVM_PROT_READ | UVM_PROT_WRITE; |
101 | vm_prot_t maxprot = UVM_PROT_ALL; |
102 | |
103 | PAX_MPROTECT_ADJUST(l, &prot, &maxprot); |
104 | |
105 | error = uvm_map(&vm->vm_map, &obreak, nbreak - obreak, NULL, |
106 | UVM_UNKNOWN_OFFSET, 0, |
107 | UVM_MAPFLAG(prot, maxprot, |
108 | UVM_INH_COPY, |
109 | UVM_ADV_NORMAL, UVM_FLAG_AMAPPAD|UVM_FLAG_FIXED| |
110 | UVM_FLAG_OVERLAY|UVM_FLAG_COPYONW)); |
111 | if (error) { |
112 | #ifdef DEBUG |
113 | uprintf("sbrk: grow %#" PRIxVADDR" failed, error = %d\n" , |
114 | nbreak - obreak, error); |
115 | #endif |
116 | mutex_exit(&p->p_auxlock); |
117 | return (error); |
118 | } |
119 | vm->vm_dsize += atop(nbreak - obreak); |
120 | } else { |
121 | uvm_deallocate(&vm->vm_map, nbreak, obreak - nbreak); |
122 | vm->vm_dsize -= atop(obreak - nbreak); |
123 | } |
124 | mutex_exit(&p->p_auxlock); |
125 | |
126 | return (0); |
127 | } |
128 | |
129 | /* |
130 | * uvm_grow: enlarge the "stack segment" to include sp. |
131 | */ |
132 | |
133 | int |
134 | uvm_grow(struct proc *p, vaddr_t sp) |
135 | { |
136 | struct vmspace *vm = p->p_vmspace; |
137 | vsize_t nss; |
138 | |
139 | /* |
140 | * For user defined stacks (from sendsig). |
141 | */ |
142 | #ifdef __MACHINE_STACK_GROWS_UP |
143 | if (sp < (vaddr_t)vm->vm_minsaddr) |
144 | #else |
145 | if (sp < (vaddr_t)vm->vm_maxsaddr) |
146 | #endif |
147 | return (0); |
148 | |
149 | /* |
150 | * For common case of already allocated (from trap). |
151 | */ |
152 | #ifdef __MACHINE_STACK_GROWS_UP |
153 | if (sp < USRSTACK + ctob(vm->vm_ssize)) |
154 | #else |
155 | if (sp >= USRSTACK - ctob(vm->vm_ssize)) |
156 | #endif |
157 | return (1); |
158 | |
159 | /* |
160 | * Really need to check vs limit and increment stack size if ok. |
161 | */ |
162 | #ifdef __MACHINE_STACK_GROWS_UP |
163 | nss = btoc(sp - USRSTACK); |
164 | #else |
165 | nss = btoc(USRSTACK - sp); |
166 | #endif |
167 | if (nss > btoc(p->p_rlimit[RLIMIT_STACK].rlim_cur)) |
168 | return (0); |
169 | vm->vm_ssize = nss; |
170 | return (1); |
171 | } |
172 | |
173 | /* |
174 | * sys_oadvise: old advice system call |
175 | */ |
176 | |
177 | /* ARGSUSED */ |
178 | int |
179 | sys_ovadvise(struct lwp *l, const struct sys_ovadvise_args *uap, register_t *retval) |
180 | { |
181 | #if 0 |
182 | /* { |
183 | syscallarg(int) anom; |
184 | } */ |
185 | #endif |
186 | |
187 | return (EINVAL); |
188 | } |
189 | |