| 1 | /* $NetBSD: uvm_coredump.c,v 1.6 2014/01/07 07:59:03 dsl 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 | * |
| 7 | * All rights reserved. |
| 8 | * |
| 9 | * This code is derived from software contributed to Berkeley by |
| 10 | * The Mach Operating System project at Carnegie-Mellon University. |
| 11 | * |
| 12 | * Redistribution and use in source and binary forms, with or without |
| 13 | * modification, are permitted provided that the following conditions |
| 14 | * are met: |
| 15 | * 1. Redistributions of source code must retain the above copyright |
| 16 | * notice, this list of conditions and the following disclaimer. |
| 17 | * 2. Redistributions in binary form must reproduce the above copyright |
| 18 | * notice, this list of conditions and the following disclaimer in the |
| 19 | * documentation and/or other materials provided with the distribution. |
| 20 | * 3. Neither the name of the University nor the names of its contributors |
| 21 | * may be used to endorse or promote products derived from this software |
| 22 | * without specific prior written permission. |
| 23 | * |
| 24 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| 25 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 26 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 27 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| 28 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 29 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 30 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 31 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 32 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 33 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 34 | * SUCH DAMAGE. |
| 35 | * |
| 36 | * @(#)vm_glue.c 8.6 (Berkeley) 1/5/94 |
| 37 | * from: Id: uvm_glue.c,v 1.1.2.8 1998/02/07 01:16:54 chs Exp |
| 38 | * |
| 39 | * |
| 40 | * Copyright (c) 1987, 1990 Carnegie-Mellon University. |
| 41 | * All rights reserved. |
| 42 | * |
| 43 | * Permission to use, copy, modify and distribute this software and |
| 44 | * its documentation is hereby granted, provided that both the copyright |
| 45 | * notice and this permission notice appear in all copies of the |
| 46 | * software, derivative works or modified versions, and any portions |
| 47 | * thereof, and that both notices appear in supporting documentation. |
| 48 | * |
| 49 | * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" |
| 50 | * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND |
| 51 | * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. |
| 52 | * |
| 53 | * Carnegie Mellon requests users of this software to return to |
| 54 | * |
| 55 | * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU |
| 56 | * School of Computer Science |
| 57 | * Carnegie Mellon University |
| 58 | * Pittsburgh PA 15213-3890 |
| 59 | * |
| 60 | * any improvements or extensions that they make and grant Carnegie the |
| 61 | * rights to redistribute these changes. |
| 62 | */ |
| 63 | |
| 64 | #include <sys/cdefs.h> |
| 65 | __KERNEL_RCSID(0, "$NetBSD: uvm_coredump.c,v 1.6 2014/01/07 07:59:03 dsl Exp $" ); |
| 66 | |
| 67 | /* |
| 68 | * uvm_coredump.c: glue functions for coredump |
| 69 | */ |
| 70 | |
| 71 | #include <sys/param.h> |
| 72 | #include <sys/systm.h> |
| 73 | #include <sys/proc.h> |
| 74 | |
| 75 | #include <uvm/uvm.h> |
| 76 | |
| 77 | /* |
| 78 | * uvm_coredump_walkmap: walk a process's map for the purpose of dumping |
| 79 | * a core file. |
| 80 | * XXX: I'm not entirely sure the locking is this function is in anyway |
| 81 | * correct. If the process isn't actually stopped then the data passed |
| 82 | * to func() is at best stale, and horrid things might happen if the |
| 83 | * entry being processed is deleted (dsl). |
| 84 | */ |
| 85 | |
| 86 | int |
| 87 | uvm_coredump_walkmap(struct proc *p, int (*func)(struct uvm_coredump_state *), |
| 88 | void *cookie) |
| 89 | { |
| 90 | struct uvm_coredump_state state; |
| 91 | struct vmspace *vm = p->p_vmspace; |
| 92 | struct vm_map *map = &vm->vm_map; |
| 93 | struct vm_map_entry *entry; |
| 94 | int error; |
| 95 | |
| 96 | entry = NULL; |
| 97 | vm_map_lock_read(map); |
| 98 | state.end = 0; |
| 99 | for (;;) { |
| 100 | if (entry == NULL) |
| 101 | entry = map->header.next; |
| 102 | else if (!uvm_map_lookup_entry(map, state.end, &entry)) |
| 103 | entry = entry->next; |
| 104 | if (entry == &map->header) |
| 105 | break; |
| 106 | |
| 107 | state.cookie = cookie; |
| 108 | if (state.end > entry->start) { |
| 109 | state.start = state.end; |
| 110 | } else { |
| 111 | state.start = entry->start; |
| 112 | } |
| 113 | state.realend = entry->end; |
| 114 | state.end = entry->end; |
| 115 | state.prot = entry->protection; |
| 116 | state.flags = 0; |
| 117 | |
| 118 | /* |
| 119 | * Dump the region unless one of the following is true: |
| 120 | * |
| 121 | * (1) the region has neither object nor amap behind it |
| 122 | * (ie. it has never been accessed). |
| 123 | * |
| 124 | * (2) the region has no amap and is read-only |
| 125 | * (eg. an executable text section). |
| 126 | * |
| 127 | * (3) the region's object is a device. |
| 128 | * |
| 129 | * (4) the region is unreadable by the process. |
| 130 | */ |
| 131 | |
| 132 | KASSERT(!UVM_ET_ISSUBMAP(entry)); |
| 133 | KASSERT(state.start < VM_MAXUSER_ADDRESS); |
| 134 | KASSERT(state.end <= VM_MAXUSER_ADDRESS); |
| 135 | if (entry->object.uvm_obj == NULL && |
| 136 | entry->aref.ar_amap == NULL) { |
| 137 | state.realend = state.start; |
| 138 | } else if ((entry->protection & VM_PROT_WRITE) == 0 && |
| 139 | entry->aref.ar_amap == NULL) { |
| 140 | state.realend = state.start; |
| 141 | } else if (entry->object.uvm_obj != NULL && |
| 142 | UVM_OBJ_IS_DEVICE(entry->object.uvm_obj)) { |
| 143 | state.realend = state.start; |
| 144 | } else if ((entry->protection & VM_PROT_READ) == 0) { |
| 145 | state.realend = state.start; |
| 146 | } else { |
| 147 | if (state.start >= (vaddr_t)vm->vm_maxsaddr) |
| 148 | state.flags |= UVM_COREDUMP_STACK; |
| 149 | |
| 150 | /* |
| 151 | * If this an anonymous entry, only dump instantiated |
| 152 | * pages. |
| 153 | */ |
| 154 | if (entry->object.uvm_obj == NULL) { |
| 155 | vaddr_t end; |
| 156 | |
| 157 | amap_lock(entry->aref.ar_amap); |
| 158 | for (end = state.start; |
| 159 | end < state.end; end += PAGE_SIZE) { |
| 160 | struct vm_anon *anon; |
| 161 | anon = amap_lookup(&entry->aref, |
| 162 | end - entry->start); |
| 163 | /* |
| 164 | * If we have already encountered an |
| 165 | * uninstantiated page, stop at the |
| 166 | * first instantied page. |
| 167 | */ |
| 168 | if (anon != NULL && |
| 169 | state.realend != state.end) { |
| 170 | state.end = end; |
| 171 | break; |
| 172 | } |
| 173 | |
| 174 | /* |
| 175 | * If this page is the first |
| 176 | * uninstantiated page, mark this as |
| 177 | * the real ending point. Continue to |
| 178 | * counting uninstantiated pages. |
| 179 | */ |
| 180 | if (anon == NULL && |
| 181 | state.realend == state.end) { |
| 182 | state.realend = end; |
| 183 | } |
| 184 | } |
| 185 | amap_unlock(entry->aref.ar_amap); |
| 186 | } |
| 187 | } |
| 188 | |
| 189 | vm_map_unlock_read(map); |
| 190 | error = (*func)(&state); |
| 191 | if (error) |
| 192 | return (error); |
| 193 | vm_map_lock_read(map); |
| 194 | } |
| 195 | vm_map_unlock_read(map); |
| 196 | |
| 197 | return (0); |
| 198 | } |
| 199 | |
| 200 | static int |
| 201 | count_segs(struct uvm_coredump_state *s) |
| 202 | { |
| 203 | (*(int *)s->cookie)++; |
| 204 | |
| 205 | return 0; |
| 206 | } |
| 207 | |
| 208 | int |
| 209 | uvm_coredump_count_segs(struct proc *p) |
| 210 | { |
| 211 | int count = 0; |
| 212 | |
| 213 | uvm_coredump_walkmap(p, count_segs, &count); |
| 214 | return count; |
| 215 | } |
| 216 | |