xref: /freebsd/lib/libkvm/kvm_minidump_arm.c (revision 895f86f15fbf6540071feb9328c3c50ed1f027b8)
1 /*-
2  * Copyright (c) 2008 Semihalf, Grzegorz Bernacki
3  * Copyright (c) 2006 Peter Wemm
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  * From: FreeBSD: src/lib/libkvm/kvm_minidump_i386.c,v 1.2 2006/06/05 08:51:14
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 /*
33  * ARM machine dependent routines for kvm and minidumps.
34  */
35 
36 #include <sys/endian.h>
37 #include <sys/param.h>
38 #include <kvm.h>
39 #include <limits.h>
40 #include <stdint.h>
41 #include <stdlib.h>
42 #include <string.h>
43 #include <unistd.h>
44 
45 #include "../../sys/arm/include/minidump.h"
46 
47 #include "kvm_private.h"
48 #include "kvm_arm.h"
49 
50 #define	arm_round_page(x)	roundup2((kvaddr_t)(x), ARM_PAGE_SIZE)
51 
52 struct vmstate {
53 	struct		minidumphdr hdr;
54 	struct		hpt hpt;
55 	void		*ptemap;
56 	unsigned char	ei_data;
57 };
58 
59 static int
60 _arm_minidump_probe(kvm_t *kd)
61 {
62 
63 	return (_kvm_probe_elf_kernel(kd, ELFCLASS32, EM_ARM) &&
64 	    _kvm_is_minidump(kd));
65 }
66 
67 static void
68 _arm_minidump_freevtop(kvm_t *kd)
69 {
70 	struct vmstate *vm = kd->vmst;
71 
72 	_kvm_hpt_free(&vm->hpt);
73 	if (vm->ptemap)
74 		free(vm->ptemap);
75 	free(vm);
76 	kd->vmst = NULL;
77 }
78 
79 static int
80 _arm_minidump_initvtop(kvm_t *kd)
81 {
82 	struct vmstate *vmst;
83 	uint32_t *bitmap;
84 	off_t off;
85 
86 	vmst = _kvm_malloc(kd, sizeof(*vmst));
87 	if (vmst == 0) {
88 		_kvm_err(kd, kd->program, "cannot allocate vm");
89 		return (-1);
90 	}
91 
92 	kd->vmst = vmst;
93 
94 	if (pread(kd->pmfd, &vmst->hdr,
95 	    sizeof(vmst->hdr), 0) != sizeof(vmst->hdr)) {
96 		_kvm_err(kd, kd->program, "cannot read dump header");
97 		return (-1);
98 	}
99 
100 	if (strncmp(MINIDUMP_MAGIC, vmst->hdr.magic,
101 	    sizeof(vmst->hdr.magic)) != 0) {
102 		_kvm_err(kd, kd->program, "not a minidump for this platform");
103 		return (-1);
104 	}
105 	vmst->hdr.version = _kvm32toh(kd, vmst->hdr.version);
106 	if (vmst->hdr.version != MINIDUMP_VERSION) {
107 		_kvm_err(kd, kd->program, "wrong minidump version. "
108 		    "Expected %d got %d", MINIDUMP_VERSION, vmst->hdr.version);
109 		return (-1);
110 	}
111 	vmst->hdr.msgbufsize = _kvm32toh(kd, vmst->hdr.msgbufsize);
112 	vmst->hdr.bitmapsize = _kvm32toh(kd, vmst->hdr.bitmapsize);
113 	vmst->hdr.ptesize = _kvm32toh(kd, vmst->hdr.ptesize);
114 	vmst->hdr.kernbase = _kvm32toh(kd, vmst->hdr.kernbase);
115 
116 	/* Skip header and msgbuf */
117 	off = ARM_PAGE_SIZE + arm_round_page(vmst->hdr.msgbufsize);
118 
119 	bitmap = _kvm_malloc(kd, vmst->hdr.bitmapsize);
120 	if (bitmap == NULL) {
121 		_kvm_err(kd, kd->program, "cannot allocate %d bytes for "
122 		    "bitmap", vmst->hdr.bitmapsize);
123 		return (-1);
124 	}
125 
126 	if (pread(kd->pmfd, bitmap, vmst->hdr.bitmapsize, off) !=
127 	    (ssize_t)vmst->hdr.bitmapsize) {
128 		_kvm_err(kd, kd->program, "cannot read %d bytes for page bitmap",
129 		    vmst->hdr.bitmapsize);
130 		free(bitmap);
131 		return (-1);
132 	}
133 	off += arm_round_page(vmst->hdr.bitmapsize);
134 
135 	vmst->ptemap = _kvm_malloc(kd, vmst->hdr.ptesize);
136 	if (vmst->ptemap == NULL) {
137 		_kvm_err(kd, kd->program, "cannot allocate %d bytes for "
138 		    "ptemap", vmst->hdr.ptesize);
139 		free(bitmap);
140 		return (-1);
141 	}
142 
143 	if (pread(kd->pmfd, vmst->ptemap, vmst->hdr.ptesize, off) !=
144 	    (ssize_t)vmst->hdr.ptesize) {
145 		_kvm_err(kd, kd->program, "cannot read %d bytes for ptemap",
146 		    vmst->hdr.ptesize);
147 		free(bitmap);
148 		return (-1);
149 	}
150 
151 	off += vmst->hdr.ptesize;
152 
153 	/* Build physical address hash table for sparse pages */
154 	_kvm_hpt_init(kd, &vmst->hpt, bitmap, vmst->hdr.bitmapsize, off,
155 	    ARM_PAGE_SIZE, sizeof(*bitmap));
156 	free(bitmap);
157 
158 	return (0);
159 }
160 
161 static int
162 _arm_minidump_kvatop(kvm_t *kd, kvaddr_t va, off_t *pa)
163 {
164 	struct vmstate *vm;
165 	arm_pt_entry_t pte;
166 	arm_physaddr_t offset, a;
167 	kvaddr_t pteindex;
168 	off_t ofs;
169 	arm_pt_entry_t *ptemap;
170 
171 	if (ISALIVE(kd)) {
172 		_kvm_err(kd, 0, "_arm_minidump_kvatop called in live kernel!");
173 		return (0);
174 	}
175 
176 	vm = kd->vmst;
177 	ptemap = vm->ptemap;
178 
179 	if (va >= vm->hdr.kernbase) {
180 		pteindex = (va - vm->hdr.kernbase) >> ARM_PAGE_SHIFT;
181 		pte = _kvm32toh(kd, ptemap[pteindex]);
182 		if (!pte) {
183 			_kvm_err(kd, kd->program,
184 			    "_arm_minidump_kvatop: pte not valid");
185 			goto invalid;
186 		}
187 		if ((pte & ARM_L2_TYPE_MASK) == ARM_L2_TYPE_L) {
188 			offset = va & ARM_L2_L_OFFSET;
189 			a = pte & ARM_L2_L_FRAME;
190 		} else if ((pte & ARM_L2_TYPE_MASK) == ARM_L2_TYPE_S) {
191 			offset = va & ARM_L2_S_OFFSET;
192 			a = pte & ARM_L2_S_FRAME;
193 		} else
194 			goto invalid;
195 
196 		ofs = _kvm_hpt_find(&vm->hpt, a);
197 		if (ofs == -1) {
198 			_kvm_err(kd, kd->program, "_arm_minidump_kvatop: "
199 			    "physical address 0x%jx not in minidump",
200 			    (uintmax_t)a);
201 			goto invalid;
202 		}
203 
204 		*pa = ofs + offset;
205 		return (ARM_PAGE_SIZE - offset);
206 
207 	} else
208 		_kvm_err(kd, kd->program, "_arm_minidump_kvatop: virtual "
209 		    "address 0x%jx not minidumped", (uintmax_t)va);
210 
211 invalid:
212 	_kvm_err(kd, 0, "invalid address (0x%jx)", (uintmax_t)va);
213 	return (0);
214 }
215 
216 struct kvm_arch kvm_arm_minidump = {
217 	.ka_probe = _arm_minidump_probe,
218 	.ka_initvtop = _arm_minidump_initvtop,
219 	.ka_freevtop = _arm_minidump_freevtop,
220 	.ka_kvatop = _arm_minidump_kvatop,
221 	.ka_native = _arm_native,
222 };
223 
224 KVM_ARCH(kvm_arm_minidump);
225