/* $NetBSD: uvm_coredump.c,v 1.8 2020/02/23 15:46:43 ad Exp $ */
/*
* Copyright (c) 1997 Charles D. Cranor and Washington University.
* Copyright (c) 1991, 1993, The Regents of the University of California.
*
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* The Mach Operating System project at Carnegie-Mellon University.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)vm_glue.c 8.6 (Berkeley) 1/5/94
* from: Id: uvm_glue.c,v 1.1.2.8 1998/02/07 01:16:54 chs Exp
*
*
* Copyright (c) 1987, 1990 Carnegie-Mellon University.
* All rights reserved.
*
* Permission to use, copy, modify and distribute this software and
* its documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
* FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or
[email protected]
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie the
* rights to redistribute these changes.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: uvm_coredump.c,v 1.8 2020/02/23 15:46:43 ad Exp $");
/*
* uvm_coredump.c: glue functions for coredump
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <uvm/uvm.h>
/*
* uvm_coredump_walkmap: walk a process's map for the purpose of dumping
* a core file.
* XXX: I'm not entirely sure the locking is this function is in anyway
* correct. If the process isn't actually stopped then the data passed
* to func() is at best stale, and horrid things might happen if the
* entry being processed is deleted (dsl).
*/
int
uvm_coredump_walkmap(struct proc *p, int (*func)(struct uvm_coredump_state *),
void *cookie)
{
struct uvm_coredump_state state;
struct vmspace *vm = p->p_vmspace;
struct vm_map *map = &vm->vm_map;
struct vm_map_entry *entry;
int error;
entry = NULL;
vm_map_lock_read(map);
state.end = 0;
for (;;) {
if (entry == NULL)
entry = map->header.next;
else if (!uvm_map_lookup_entry(map, state.end, &entry))
entry = entry->next;
if (entry == &map->header)
break;
state.cookie = cookie;
if (state.end > entry->start) {
state.start = state.end;
} else {
state.start = entry->start;
}
state.realend = entry->end;
state.end = entry->end;
state.prot = entry->protection;
state.flags = 0;
/*
* Dump the region unless one of the following is true:
*
* (1) the region has neither object nor amap behind it
* (ie. it has never been accessed).
*
* (2) the region has no amap and is read-only
* (eg. an executable text section).
*
* (3) the region's object is a device.
*
* (4) the region is unreadable by the process.
*/
KASSERT(!UVM_ET_ISSUBMAP(entry));
#ifdef VM_MAXUSER_ADDRESS
KASSERT(state.start < VM_MAXUSER_ADDRESS);
KASSERT(state.end <= VM_MAXUSER_ADDRESS);
#endif
if (entry->object.uvm_obj == NULL &&
entry->aref.ar_amap == NULL) {
state.realend = state.start;
} else if ((entry->protection & VM_PROT_WRITE) == 0 &&
entry->aref.ar_amap == NULL) {
state.realend = state.start;
} else if (entry->object.uvm_obj != NULL &&
UVM_OBJ_IS_DEVICE(entry->object.uvm_obj)) {
state.realend = state.start;
} else if ((entry->protection & VM_PROT_READ) == 0) {
state.realend = state.start;
} else {
if (state.start >= (vaddr_t)vm->vm_maxsaddr)
state.flags |= UVM_COREDUMP_STACK;
/*
* If this an anonymous entry, only dump instantiated
* pages.
*/
if (entry->object.uvm_obj == NULL) {
vaddr_t end;
amap_lock(entry->aref.ar_amap, RW_READER);
for (end = state.start;
end < state.end; end += PAGE_SIZE) {
struct vm_anon *anon;
anon = amap_lookup(&entry->aref,
end - entry->start);
/*
* If we have already encountered an
* uninstantiated page, stop at the
* first instantied page.
*/
if (anon != NULL &&
state.realend != state.end) {
state.end = end;
break;
}
/*
* If this page is the first
* uninstantiated page, mark this as
* the real ending point. Continue to
* counting uninstantiated pages.
*/
if (anon == NULL &&
state.realend == state.end) {
state.realend = end;
}
}
amap_unlock(entry->aref.ar_amap);
}
}
vm_map_unlock_read(map);
error = (*func)(&state);
if (error)
return (error);
vm_map_lock_read(map);
}
vm_map_unlock_read(map);
return (0);
}
static int
count_segs(struct uvm_coredump_state *s)
{
(*(int *)s->cookie)++;
return 0;
}
int
uvm_coredump_count_segs(struct proc *p)
{
int count = 0;
uvm_coredump_walkmap(p, count_segs, &count);
return count;
}
