kvm_ia64.c revision 115084 
1/* $FreeBSD: head/lib/libkvm/kvm_ia64.c 115084 2003-05-16 21:26:42Z marcel $ */
2/*	$NetBSD: kvm_alpha.c,v 1.7.2.1 1997/11/02 20:34:26 mellon Exp $	*/
3
4/*
5 * Copyright (c) 1994, 1995 Carnegie-Mellon University.
6 * All rights reserved.
7 *
8 * Author: Chris G. Demetriou
9 *
10 * Permission to use, copy, modify and distribute this software and
11 * its documentation is hereby granted, provided that both the copyright
12 * notice and this permission notice appear in all copies of the
13 * software, derivative works or modified versions, and any portions
14 * thereof, and that both notices appear in supporting documentation.
15 *
16 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
17 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
18 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
19 *
20 * Carnegie Mellon requests users of this software to return to
21 *
22 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
23 *  School of Computer Science
24 *  Carnegie Mellon University
25 *  Pittsburgh PA 15213-3890
26 *
27 * any improvements or extensions that they make and grant Carnegie the
28 * rights to redistribute these changes.
29 */
30
31#include <sys/types.h>
32#include <sys/elf64.h>
33#include <sys/mman.h>
34
35#include <machine/pte.h>
36
37#include <kvm.h>
38#include <limits.h>
39#include <stdlib.h>
40#include <unistd.h>
41
42#include "kvm_private.h"
43
44#define	REGION_BASE(n)		(((uint64_t)(n)) << 61)
45#define	REGION_ADDR(x)		((x) & ((1LL<<61)-1LL))
46
47#define	NKPTEPG(ps)		((ps) / sizeof(struct ia64_lpte))
48#define	KPTE_PTE_INDEX(va,ps)	(((va)/(ps)) % NKPTEPG(ps))
49#define	KPTE_DIR_INDEX(va,ps)	(((va)/(ps)) / NKPTEPG(ps))
50
51struct vmstate {
52	void	*mmapbase;
53	size_t	mmapsize;
54	size_t	pagesize;
55	u_long	kptdir;
56};
57
58/*
59 * Map the ELF headers into the process' address space. We do this in two
60 * steps: first the ELF header itself and using that information the whole
61 * set of headers.
62 */
63static int
64_kvm_maphdrs(kvm_t *kd, size_t sz)
65{
66	struct vmstate *vm = kd->vmst;
67
68	/* munmap() previous mmap(). */
69	if (vm->mmapbase != NULL) {
70		munmap(vm->mmapbase, vm->mmapsize);
71		vm->mmapbase = NULL;
72	}
73
74	vm->mmapsize = sz;
75	vm->mmapbase = mmap(NULL, sz, PROT_READ, MAP_PRIVATE, kd->pmfd, NULL);
76	if (vm->mmapbase == MAP_FAILED) {
77		_kvm_err(kd, kd->program, "cannot mmap corefile");
78		return (-1);
79	}
80
81	return (0);
82}
83
84/*
85 * Translate a physical memory address to a file-offset in the crash-dump.
86 */
87static size_t
88_kvm_pa2off(kvm_t *kd, uint64_t pa, u_long *ofs, size_t pgsz)
89{
90	Elf64_Ehdr *e = kd->vmst->mmapbase;
91	Elf64_Phdr *p = (Elf64_Phdr*)((char*)e + e->e_phoff);
92	int n = e->e_phnum;
93
94	if (pa != REGION_ADDR(pa)) {
95		_kvm_err(kd, kd->program, "internal error");
96		return (0);
97	}
98
99	while (n && (pa < p->p_paddr || pa >= p->p_paddr + p->p_memsz))
100		p++, n--;
101	if (n == 0)
102		return (0);
103
104	*ofs = (pa - p->p_paddr) + p->p_offset;
105	if (pgsz == 0)
106		return (p->p_memsz - (pa - p->p_paddr));
107	return (pgsz - ((size_t)pa & (pgsz - 1)));
108}
109
110void
111_kvm_freevtop(kvm_t *kd)
112{
113	struct vmstate *vm = kd->vmst;
114
115	if (vm->mmapbase != NULL)
116		munmap(vm->mmapbase, vm->mmapsize);
117	free(vm);
118	kd->vmst = NULL;
119}
120
121int
122_kvm_initvtop(kvm_t *kd)
123{
124	struct nlist nlist[2];
125	uint64_t va;
126	Elf64_Ehdr *ehdr;
127	size_t hdrsz;
128
129	kd->vmst = (struct vmstate *)_kvm_malloc(kd, sizeof(*kd->vmst));
130	if (kd->vmst == NULL) {
131		_kvm_err(kd, kd->program, "cannot allocate vm");
132		return (-1);
133	}
134
135	kd->vmst->pagesize = getpagesize();
136
137	if (_kvm_maphdrs(kd, sizeof(Elf64_Ehdr)) == -1)
138		return (-1);
139
140	ehdr = kd->vmst->mmapbase;
141	hdrsz = ehdr->e_phoff + ehdr->e_phentsize * ehdr->e_phnum;
142	if (_kvm_maphdrs(kd, hdrsz) == -1)
143		return (-1);
144
145	/*
146	 * At this point we've got enough information to use kvm_read() for
147	 * direct mapped (ie region 6 and region 7) address, such as symbol
148	 * addresses/values.
149	 */
150
151	nlist[0].n_name = "ia64_kptdir";
152	nlist[1].n_name = 0;
153
154	if (kvm_nlist(kd, nlist) != 0) {
155		_kvm_err(kd, kd->program, "bad namelist");
156		return (-1);
157	}
158
159	if (kvm_read(kd, (nlist[0].n_value), &va, sizeof(va)) != sizeof(va)) {
160		_kvm_err(kd, kd->program, "cannot read kptdir");
161		return (-1);
162	}
163
164	if (va < REGION_BASE(6)) {
165		_kvm_err(kd, kd->program, "kptdir is itself virtual");
166		return (-1);
167	}
168
169	kd->vmst->kptdir = va;
170	return (0);
171}
172
173int
174_kvm_kvatop(kvm_t *kd, u_long va, u_long *pa)
175{
176	struct ia64_lpte pte;
177	uint64_t pgaddr, ptaddr;
178	size_t pgno, pgsz, ptno;
179
180	if (va >= REGION_BASE(6)) {
181		/* Regions 6 and 7: direct mapped. */
182		return (_kvm_pa2off(kd, REGION_ADDR(va), pa, 0));
183	} else if (va >= REGION_BASE(5)) {
184		/* Region 5: virtual. */
185		va = REGION_ADDR(va);
186		pgsz = kd->vmst->pagesize;
187		ptno = KPTE_DIR_INDEX(va, pgsz);
188		pgno = KPTE_PTE_INDEX(va, pgsz);
189		if (ptno >= (pgsz >> 3))
190			goto fail;
191		ptaddr = kd->vmst->kptdir + (ptno << 3);
192		if (kvm_read(kd, ptaddr, &pgaddr, 8) != 8)
193			goto fail;
194		if (pgaddr == 0)
195			goto fail;
196		pgaddr += (pgno * sizeof(pte));
197		if (kvm_read(kd, pgaddr, &pte, sizeof(pte)) != sizeof(pte))
198			goto fail;
199		if (!pte.pte_p)
200			goto fail;
201		va = ((u_long)pte.pte_ppn << 12) + (va & (pgsz - 1));
202		return (_kvm_pa2off(kd, va, pa, pgsz));
203	}
204
205 fail:
206	_kvm_err(kd, kd->program, "invalid kernel virtual address");
207	*pa = ~0UL;
208	return (0);
209}
210