1/*-
2 * Copyright (c) 1989, 1992, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * This code is derived from software developed by the Computer Systems
6 * Engineering group at Lawrence Berkeley Laboratory under DARPA contract
7 * BG 91-66 and contributed to Berkeley.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 * 4. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#include <sys/cdefs.h>
35__FBSDID("$FreeBSD$");
36
37#if defined(LIBC_SCCS) && !defined(lint)
38#if 0
39static char sccsid[] = "@(#)kvm_hp300.c	8.1 (Berkeley) 6/4/93";
40#endif
41#endif /* LIBC_SCCS and not lint */
42
43/*
44 * AMD64 machine dependent routines for kvm.  Hopefully, the forthcoming
45 * vm code will one day obsolete this module.
46 */
47
48#include <sys/param.h>
49#include <sys/user.h>
50#include <sys/proc.h>
51#include <sys/stat.h>
52#include <sys/mman.h>
53#include <stdlib.h>
54#include <string.h>
55#include <unistd.h>
56#include <nlist.h>
57#include <kvm.h>
58
59#include <vm/vm.h>
60#include <vm/vm_param.h>
61
62#include <machine/elf.h>
63
64#include <limits.h>
65
66#include "kvm_private.h"
67
68#ifndef btop
69#define	btop(x)		(amd64_btop(x))
70#define	ptob(x)		(amd64_ptob(x))
71#endif
72
73/* minidump must be the first item! */
74struct vmstate {
75	int		minidump;	/* 1 = minidump mode */
76	void		*mmapbase;
77	size_t		mmapsize;
78	pml4_entry_t	*PML4;
79};
80
81/*
82 * Map the ELF headers into the process' address space. We do this in two
83 * steps: first the ELF header itself and using that information the whole
84 * set of headers. (Taken from kvm_ia64.c)
85 */
86static int
87_kvm_maphdrs(kvm_t *kd, size_t sz)
88{
89	struct vmstate *vm = kd->vmst;
90
91	/* munmap() previous mmap(). */
92	if (vm->mmapbase != NULL) {
93		munmap(vm->mmapbase, vm->mmapsize);
94		vm->mmapbase = NULL;
95	}
96
97	vm->mmapsize = sz;
98	vm->mmapbase = mmap(NULL, sz, PROT_READ, MAP_PRIVATE, kd->pmfd, 0);
99	if (vm->mmapbase == MAP_FAILED) {
100		_kvm_err(kd, kd->program, "cannot mmap corefile");
101		return (-1);
102	}
103	return (0);
104}
105
106/*
107 * Translate a physical memory address to a file-offset in the crash-dump.
108 * (Taken from kvm_ia64.c)
109 */
110static size_t
111_kvm_pa2off(kvm_t *kd, uint64_t pa, off_t *ofs)
112{
113	Elf_Ehdr *e = kd->vmst->mmapbase;
114	Elf_Phdr *p;
115	int n;
116
117	if (kd->rawdump) {
118		*ofs = pa;
119		return (PAGE_SIZE - ((size_t)pa & PAGE_MASK));
120	}
121
122	p = (Elf_Phdr*)((char*)e + e->e_phoff);
123	n = e->e_phnum;
124	while (n && (pa < p->p_paddr || pa >= p->p_paddr + p->p_memsz))
125		p++, n--;
126	if (n == 0)
127		return (0);
128	*ofs = (pa - p->p_paddr) + p->p_offset;
129	return (PAGE_SIZE - ((size_t)pa & PAGE_MASK));
130}
131
132void
133_kvm_freevtop(kvm_t *kd)
134{
135	struct vmstate *vm = kd->vmst;
136
137	if (kd->vmst->minidump)
138		return (_kvm_minidump_freevtop(kd));
139	if (vm->mmapbase != NULL)
140		munmap(vm->mmapbase, vm->mmapsize);
141	if (vm->PML4)
142		free(vm->PML4);
143	free(vm);
144	kd->vmst = NULL;
145}
146
147int
148_kvm_initvtop(kvm_t *kd)
149{
150	struct nlist nl[2];
151	u_long pa;
152	u_long kernbase;
153	pml4_entry_t	*PML4;
154	Elf_Ehdr *ehdr;
155	size_t hdrsz;
156	char minihdr[8];
157
158	if (!kd->rawdump && pread(kd->pmfd, &minihdr, 8, 0) == 8)
159		if (memcmp(&minihdr, "minidump", 8) == 0)
160			return (_kvm_minidump_initvtop(kd));
161
162	kd->vmst = (struct vmstate *)_kvm_malloc(kd, sizeof(*kd->vmst));
163	if (kd->vmst == 0) {
164		_kvm_err(kd, kd->program, "cannot allocate vm");
165		return (-1);
166	}
167	kd->vmst->PML4 = 0;
168
169	if (kd->rawdump == 0) {
170		if (_kvm_maphdrs(kd, sizeof(Elf_Ehdr)) == -1)
171			return (-1);
172
173		ehdr = kd->vmst->mmapbase;
174		hdrsz = ehdr->e_phoff + ehdr->e_phentsize * ehdr->e_phnum;
175		if (_kvm_maphdrs(kd, hdrsz) == -1)
176			return (-1);
177	}
178
179	nl[0].n_name = "kernbase";
180	nl[1].n_name = 0;
181
182	if (kvm_nlist(kd, nl) != 0) {
183		_kvm_err(kd, kd->program, "bad namelist - no kernbase");
184		return (-1);
185	}
186	kernbase = nl[0].n_value;
187
188	nl[0].n_name = "KPML4phys";
189	nl[1].n_name = 0;
190
191	if (kvm_nlist(kd, nl) != 0) {
192		_kvm_err(kd, kd->program, "bad namelist - no KPML4phys");
193		return (-1);
194	}
195	if (kvm_read(kd, (nl[0].n_value - kernbase), &pa, sizeof(pa)) !=
196	    sizeof(pa)) {
197		_kvm_err(kd, kd->program, "cannot read KPML4phys");
198		return (-1);
199	}
200	PML4 = _kvm_malloc(kd, PAGE_SIZE);
201	if (kvm_read(kd, pa, PML4, PAGE_SIZE) != PAGE_SIZE) {
202		_kvm_err(kd, kd->program, "cannot read KPML4phys");
203		return (-1);
204	}
205	kd->vmst->PML4 = PML4;
206	return (0);
207}
208
209static int
210_kvm_vatop(kvm_t *kd, u_long va, off_t *pa)
211{
212	struct vmstate *vm;
213	u_long offset;
214	u_long pdpe_pa;
215	u_long pde_pa;
216	u_long pte_pa;
217	pml4_entry_t pml4e;
218	pdp_entry_t pdpe;
219	pd_entry_t pde;
220	pt_entry_t pte;
221	u_long pml4eindex;
222	u_long pdpeindex;
223	u_long pdeindex;
224	u_long pteindex;
225	u_long a;
226	off_t ofs;
227	size_t s;
228
229	vm = kd->vmst;
230	offset = va & (PAGE_SIZE - 1);
231
232	/*
233	 * If we are initializing (kernel page table descriptor pointer
234	 * not yet set) then return pa == va to avoid infinite recursion.
235	 */
236	if (vm->PML4 == 0) {
237		s = _kvm_pa2off(kd, va, pa);
238		if (s == 0) {
239			_kvm_err(kd, kd->program,
240			    "_kvm_vatop: bootstrap data not in dump");
241			goto invalid;
242		} else
243			return (PAGE_SIZE - offset);
244	}
245
246	pml4eindex = (va >> PML4SHIFT) & (NPML4EPG - 1);
247	pml4e = vm->PML4[pml4eindex];
248	if (((u_long)pml4e & PG_V) == 0) {
249		_kvm_err(kd, kd->program, "_kvm_vatop: pml4e not valid");
250		goto invalid;
251	}
252
253	pdpeindex = (va >> PDPSHIFT) & (NPDPEPG-1);
254	pdpe_pa = ((u_long)pml4e & PG_FRAME) +
255	    (pdpeindex * sizeof(pdp_entry_t));
256
257	s = _kvm_pa2off(kd, pdpe_pa, &ofs);
258	if (s < sizeof pdpe) {
259		_kvm_err(kd, kd->program, "_kvm_vatop: pdpe_pa not found");
260		goto invalid;
261	}
262	if (lseek(kd->pmfd, ofs, 0) == -1) {
263		_kvm_syserr(kd, kd->program, "_kvm_vatop: lseek pdpe_pa");
264		goto invalid;
265	}
266	if (read(kd->pmfd, &pdpe, sizeof pdpe) != sizeof pdpe) {
267		_kvm_syserr(kd, kd->program, "_kvm_vatop: read pdpe");
268		goto invalid;
269	}
270	if (((u_long)pdpe & PG_V) == 0) {
271		_kvm_err(kd, kd->program, "_kvm_vatop: pdpe not valid");
272		goto invalid;
273	}
274
275	pdeindex = (va >> PDRSHIFT) & (NPDEPG-1);
276	pde_pa = ((u_long)pdpe & PG_FRAME) + (pdeindex * sizeof(pd_entry_t));
277
278	s = _kvm_pa2off(kd, pde_pa, &ofs);
279	if (s < sizeof pde) {
280		_kvm_syserr(kd, kd->program, "_kvm_vatop: pde_pa not found");
281		goto invalid;
282	}
283	if (lseek(kd->pmfd, ofs, 0) == -1) {
284		_kvm_err(kd, kd->program, "_kvm_vatop: lseek pde_pa");
285		goto invalid;
286	}
287	if (read(kd->pmfd, &pde, sizeof pde) != sizeof pde) {
288		_kvm_syserr(kd, kd->program, "_kvm_vatop: read pde");
289		goto invalid;
290	}
291	if (((u_long)pde & PG_V) == 0) {
292		_kvm_err(kd, kd->program, "_kvm_vatop: pde not valid");
293		goto invalid;
294	}
295
296	if ((u_long)pde & PG_PS) {
297	      /*
298	       * No final-level page table; ptd describes one 2MB page.
299	       */
300#define	PAGE2M_MASK	(NBPDR - 1)
301#define	PG_FRAME2M	(~PAGE2M_MASK)
302		a = ((u_long)pde & PG_FRAME2M) + (va & PAGE2M_MASK);
303		s = _kvm_pa2off(kd, a, pa);
304		if (s == 0) {
305			_kvm_err(kd, kd->program,
306			    "_kvm_vatop: 2MB page address not in dump");
307			goto invalid;
308		} else
309			return (NBPDR - (va & PAGE2M_MASK));
310	}
311
312	pteindex = (va >> PAGE_SHIFT) & (NPTEPG-1);
313	pte_pa = ((u_long)pde & PG_FRAME) + (pteindex * sizeof(pt_entry_t));
314
315	s = _kvm_pa2off(kd, pte_pa, &ofs);
316	if (s < sizeof pte) {
317		_kvm_err(kd, kd->program, "_kvm_vatop: pte_pa not found");
318		goto invalid;
319	}
320	if (lseek(kd->pmfd, ofs, 0) == -1) {
321		_kvm_syserr(kd, kd->program, "_kvm_vatop: lseek");
322		goto invalid;
323	}
324	if (read(kd->pmfd, &pte, sizeof pte) != sizeof pte) {
325		_kvm_syserr(kd, kd->program, "_kvm_vatop: read");
326		goto invalid;
327	}
328	if (((u_long)pte & PG_V) == 0) {
329		_kvm_err(kd, kd->program, "_kvm_vatop: pte not valid");
330		goto invalid;
331	}
332
333	a = ((u_long)pte & PG_FRAME) + offset;
334	s = _kvm_pa2off(kd, a, pa);
335	if (s == 0) {
336		_kvm_err(kd, kd->program, "_kvm_vatop: address not in dump");
337		goto invalid;
338	} else
339		return (PAGE_SIZE - offset);
340
341invalid:
342	_kvm_err(kd, 0, "invalid address (0x%lx)", va);
343	return (0);
344}
345
346int
347_kvm_kvatop(kvm_t *kd, u_long va, off_t *pa)
348{
349
350	if (kd->vmst->minidump)
351		return (_kvm_minidump_kvatop(kd, va, pa));
352	if (ISALIVE(kd)) {
353		_kvm_err(kd, 0, "kvm_kvatop called in live kernel!");
354		return (0);
355	}
356	return (_kvm_vatop(kd, va, pa));
357}
358