xref: /freebsd/lib/libkvm/kvm_minidump_aarch64.c (revision af6a5351a1fdb1130f18be6c782c4d48916eb971)
1 /*-
2  * Copyright (c) 2006 Peter Wemm
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  *
13  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23  * SUCH DAMAGE.
24  *
25  * From: FreeBSD: src/lib/libkvm/kvm_minidump_amd64.c r261799
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 /*
32  * ARM64 (AArch64) machine dependent routines for kvm and minidumps.
33  */
34 
35 #include <sys/param.h>
36 #include <stdint.h>
37 #include <stdlib.h>
38 #include <string.h>
39 #include <unistd.h>
40 #include <kvm.h>
41 
42 #include "../../sys/arm64/include/minidump.h"
43 
44 #include <limits.h>
45 
46 #include "kvm_private.h"
47 #include "kvm_aarch64.h"
48 
49 #define	aarch64_round_page(x)	roundup2((kvaddr_t)(x), AARCH64_PAGE_SIZE)
50 
51 struct vmstate {
52 	struct minidumphdr hdr;
53 	uint64_t *page_map;
54 };
55 
56 static int
57 _aarch64_minidump_probe(kvm_t *kd)
58 {
59 
60 	return (_kvm_probe_elf_kernel(kd, ELFCLASS64, EM_AARCH64) &&
61 	    _kvm_is_minidump(kd));
62 }
63 
64 static void
65 _aarch64_minidump_freevtop(kvm_t *kd)
66 {
67 	struct vmstate *vm = kd->vmst;
68 
69 	free(vm->page_map);
70 	free(vm);
71 	kd->vmst = NULL;
72 }
73 
74 static int
75 _aarch64_minidump_initvtop(kvm_t *kd)
76 {
77 	struct vmstate *vmst;
78 	off_t off, sparse_off;
79 
80 	vmst = _kvm_malloc(kd, sizeof(*vmst));
81 	if (vmst == NULL) {
82 		_kvm_err(kd, kd->program, "cannot allocate vm");
83 		return (-1);
84 	}
85 	kd->vmst = vmst;
86 	if (pread(kd->pmfd, &vmst->hdr, sizeof(vmst->hdr), 0) !=
87 	    sizeof(vmst->hdr)) {
88 		_kvm_err(kd, kd->program, "cannot read dump header");
89 		return (-1);
90 	}
91 	if (strncmp(MINIDUMP_MAGIC, vmst->hdr.magic,
92 	    sizeof(vmst->hdr.magic)) != 0) {
93 		_kvm_err(kd, kd->program, "not a minidump for this platform");
94 		return (-1);
95 	}
96 
97 	vmst->hdr.version = le32toh(vmst->hdr.version);
98 	if (vmst->hdr.version != MINIDUMP_VERSION) {
99 		_kvm_err(kd, kd->program, "wrong minidump version. "
100 		    "Expected %d got %d", MINIDUMP_VERSION, vmst->hdr.version);
101 		return (-1);
102 	}
103 	vmst->hdr.msgbufsize = le32toh(vmst->hdr.msgbufsize);
104 	vmst->hdr.bitmapsize = le32toh(vmst->hdr.bitmapsize);
105 	vmst->hdr.pmapsize = le32toh(vmst->hdr.pmapsize);
106 	vmst->hdr.kernbase = le64toh(vmst->hdr.kernbase);
107 	vmst->hdr.dmapphys = le64toh(vmst->hdr.dmapphys);
108 	vmst->hdr.dmapbase = le64toh(vmst->hdr.dmapbase);
109 	vmst->hdr.dmapend = le64toh(vmst->hdr.dmapend);
110 
111 	/* Skip header and msgbuf */
112 	off = AARCH64_PAGE_SIZE + aarch64_round_page(vmst->hdr.msgbufsize);
113 
114 	/* build physical address lookup table for sparse pages */
115 	sparse_off = off + aarch64_round_page(vmst->hdr.bitmapsize) +
116 	    aarch64_round_page(vmst->hdr.pmapsize);
117 	if (_kvm_pt_init(kd, vmst->hdr.bitmapsize, off, sparse_off,
118 	    AARCH64_PAGE_SIZE, sizeof(uint64_t)) == -1) {
119 		_kvm_err(kd, kd->program, "cannot load core bitmap");
120 		return (-1);
121 	}
122 	off += aarch64_round_page(vmst->hdr.bitmapsize);
123 
124 	vmst->page_map = _kvm_malloc(kd, vmst->hdr.pmapsize);
125 	if (vmst->page_map == NULL) {
126 		_kvm_err(kd, kd->program,
127 		    "cannot allocate %d bytes for page_map",
128 		    vmst->hdr.pmapsize);
129 		return (-1);
130 	}
131 	/* This is the end of the dump, savecore may have truncated it. */
132 	/*
133 	 * XXX: This doesn't make sense.  The pmap is not at the end,
134 	 * and if it is truncated we don't have any actual data (it's
135 	 * all stored after the bitmap and pmap.  -- jhb
136 	 */
137 	if (pread(kd->pmfd, vmst->page_map, vmst->hdr.pmapsize, off) <
138 	    AARCH64_PAGE_SIZE) {
139 		_kvm_err(kd, kd->program, "cannot read %d bytes for page_map",
140 		    vmst->hdr.pmapsize);
141 		return (-1);
142 	}
143 	off += aarch64_round_page(vmst->hdr.pmapsize);
144 
145 	return (0);
146 }
147 
148 static int
149 _aarch64_minidump_vatop(kvm_t *kd, kvaddr_t va, off_t *pa)
150 {
151 	struct vmstate *vm;
152 	aarch64_physaddr_t offset;
153 	aarch64_pte_t l3;
154 	kvaddr_t l3_index;
155 	aarch64_physaddr_t a;
156 	off_t ofs;
157 
158 	vm = kd->vmst;
159 	offset = va & AARCH64_PAGE_MASK;
160 
161 	if (va >= vm->hdr.dmapbase && va < vm->hdr.dmapend) {
162 		a = (va - vm->hdr.dmapbase + vm->hdr.dmapphys) &
163 		    ~AARCH64_PAGE_MASK;
164 		ofs = _kvm_pt_find(kd, a);
165 		if (ofs == -1) {
166 			_kvm_err(kd, kd->program, "_aarch64_minidump_vatop: "
167 			    "direct map address 0x%jx not in minidump",
168 			    (uintmax_t)va);
169 			goto invalid;
170 		}
171 		*pa = ofs + offset;
172 		return (AARCH64_PAGE_SIZE - offset);
173 	} else if (va >= vm->hdr.kernbase) {
174 		l3_index = (va - vm->hdr.kernbase) >> AARCH64_L3_SHIFT;
175 		if (l3_index >= vm->hdr.pmapsize / sizeof(*vm->page_map))
176 			goto invalid;
177 		l3 = le64toh(vm->page_map[l3_index]);
178 		if ((l3 & AARCH64_ATTR_DESCR_MASK) != AARCH64_L3_PAGE) {
179 			_kvm_err(kd, kd->program,
180 			    "_aarch64_minidump_vatop: pde not valid");
181 			goto invalid;
182 		}
183 		a = l3 & ~AARCH64_ATTR_MASK;
184 		ofs = _kvm_pt_find(kd, a);
185 		if (ofs == -1) {
186 			_kvm_err(kd, kd->program, "_aarch64_minidump_vatop: "
187 			    "physical address 0x%jx not in minidump",
188 			    (uintmax_t)a);
189 			goto invalid;
190 		}
191 		*pa = ofs + offset;
192 		return (AARCH64_PAGE_SIZE - offset);
193 	} else {
194 		_kvm_err(kd, kd->program,
195 	    "_aarch64_minidump_vatop: virtual address 0x%jx not minidumped",
196 		    (uintmax_t)va);
197 		goto invalid;
198 	}
199 
200 invalid:
201 	_kvm_err(kd, 0, "invalid address (0x%jx)", (uintmax_t)va);
202 	return (0);
203 }
204 
205 static int
206 _aarch64_minidump_kvatop(kvm_t *kd, kvaddr_t va, off_t *pa)
207 {
208 
209 	if (ISALIVE(kd)) {
210 		_kvm_err(kd, 0,
211 		    "_aarch64_minidump_kvatop called in live kernel!");
212 		return (0);
213 	}
214 	return (_aarch64_minidump_vatop(kd, va, pa));
215 }
216 
217 static int
218 _aarch64_native(kvm_t *kd)
219 {
220 
221 #ifdef __aarch64__
222 	return (1);
223 #else
224 	return (0);
225 #endif
226 }
227 
228 struct kvm_arch kvm_aarch64_minidump = {
229 	.ka_probe = _aarch64_minidump_probe,
230 	.ka_initvtop = _aarch64_minidump_initvtop,
231 	.ka_freevtop = _aarch64_minidump_freevtop,
232 	.ka_kvatop = _aarch64_minidump_kvatop,
233 	.ka_native = _aarch64_native,
234 };
235 
236 KVM_ARCH(kvm_aarch64_minidump);
237