xref: /freebsd/lib/libkvm/kvm_minidump_arm.c (revision d96700a6da2afa88607fbd7405ade439424d10d9)
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 	void		*ptemap;
55 	unsigned char	ei_data;
56 };
57 
58 static int
59 _arm_minidump_probe(kvm_t *kd)
60 {
61 
62 	return (_kvm_probe_elf_kernel(kd, ELFCLASS32, EM_ARM) &&
63 	    _kvm_is_minidump(kd));
64 }
65 
66 static void
67 _arm_minidump_freevtop(kvm_t *kd)
68 {
69 	struct vmstate *vm = kd->vmst;
70 
71 	free(vm->ptemap);
72 	free(vm);
73 	kd->vmst = NULL;
74 }
75 
76 static int
77 _arm_minidump_initvtop(kvm_t *kd)
78 {
79 	struct vmstate *vmst;
80 	off_t off, sparse_off;
81 
82 	vmst = _kvm_malloc(kd, sizeof(*vmst));
83 	if (vmst == NULL) {
84 		_kvm_err(kd, kd->program, "cannot allocate vm");
85 		return (-1);
86 	}
87 
88 	kd->vmst = vmst;
89 
90 	if (pread(kd->pmfd, &vmst->hdr,
91 	    sizeof(vmst->hdr), 0) != sizeof(vmst->hdr)) {
92 		_kvm_err(kd, kd->program, "cannot read dump header");
93 		return (-1);
94 	}
95 
96 	if (strncmp(MINIDUMP_MAGIC, vmst->hdr.magic,
97 	    sizeof(vmst->hdr.magic)) != 0) {
98 		_kvm_err(kd, kd->program, "not a minidump for this platform");
99 		return (-1);
100 	}
101 	vmst->hdr.version = _kvm32toh(kd, vmst->hdr.version);
102 	if (vmst->hdr.version != MINIDUMP_VERSION) {
103 		_kvm_err(kd, kd->program, "wrong minidump version. "
104 		    "Expected %d got %d", MINIDUMP_VERSION, vmst->hdr.version);
105 		return (-1);
106 	}
107 	vmst->hdr.msgbufsize = _kvm32toh(kd, vmst->hdr.msgbufsize);
108 	vmst->hdr.bitmapsize = _kvm32toh(kd, vmst->hdr.bitmapsize);
109 	vmst->hdr.ptesize = _kvm32toh(kd, vmst->hdr.ptesize);
110 	vmst->hdr.kernbase = _kvm32toh(kd, vmst->hdr.kernbase);
111 	vmst->hdr.arch = _kvm32toh(kd, vmst->hdr.arch);
112 	vmst->hdr.mmuformat = _kvm32toh(kd, vmst->hdr.mmuformat);
113 	if (vmst->hdr.mmuformat == MINIDUMP_MMU_FORMAT_UNKNOWN) {
114 		/* This is a safe default as 1K pages are not used. */
115 		vmst->hdr.mmuformat = MINIDUMP_MMU_FORMAT_V6;
116 	}
117 
118 	/* Skip header and msgbuf */
119 	off = ARM_PAGE_SIZE + arm_round_page(vmst->hdr.msgbufsize);
120 
121 	sparse_off = off + arm_round_page(vmst->hdr.bitmapsize) +
122 	    arm_round_page(vmst->hdr.ptesize);
123 	if (_kvm_pt_init(kd, vmst->hdr.bitmapsize, off, sparse_off,
124 	    ARM_PAGE_SIZE, sizeof(uint32_t)) == -1) {
125 		_kvm_err(kd, kd->program, "cannot load core bitmap");
126 		return (-1);
127 	}
128 	off += arm_round_page(vmst->hdr.bitmapsize);
129 
130 	vmst->ptemap = _kvm_malloc(kd, vmst->hdr.ptesize);
131 	if (vmst->ptemap == NULL) {
132 		_kvm_err(kd, kd->program, "cannot allocate %d bytes for "
133 		    "ptemap", vmst->hdr.ptesize);
134 		return (-1);
135 	}
136 
137 	if (pread(kd->pmfd, vmst->ptemap, vmst->hdr.ptesize, off) !=
138 	    (ssize_t)vmst->hdr.ptesize) {
139 		_kvm_err(kd, kd->program, "cannot read %d bytes for ptemap",
140 		    vmst->hdr.ptesize);
141 		return (-1);
142 	}
143 	off += arm_round_page(vmst->hdr.ptesize);
144 
145 	return (0);
146 }
147 
148 static int
149 _arm_minidump_kvatop(kvm_t *kd, kvaddr_t va, off_t *pa)
150 {
151 	struct vmstate *vm;
152 	arm_pt_entry_t pte;
153 	arm_physaddr_t offset, a;
154 	kvaddr_t pteindex;
155 	off_t ofs;
156 	arm_pt_entry_t *ptemap;
157 
158 	if (ISALIVE(kd)) {
159 		_kvm_err(kd, 0, "_arm_minidump_kvatop called in live kernel!");
160 		return (0);
161 	}
162 
163 	vm = kd->vmst;
164 	ptemap = vm->ptemap;
165 
166 	if (va >= vm->hdr.kernbase) {
167 		pteindex = (va - vm->hdr.kernbase) >> ARM_PAGE_SHIFT;
168 		if (pteindex >= vm->hdr.ptesize / sizeof(*ptemap))
169 			goto invalid;
170 		pte = _kvm32toh(kd, ptemap[pteindex]);
171 		if ((pte & ARM_L2_TYPE_MASK) == ARM_L2_TYPE_INV) {
172 			_kvm_err(kd, kd->program,
173 			    "_arm_minidump_kvatop: pte not valid");
174 			goto invalid;
175 		}
176 		if ((pte & ARM_L2_TYPE_MASK) == ARM_L2_TYPE_L) {
177 			/* 64K page -> convert to be like 4K page */
178 			offset = va & ARM_L2_S_OFFSET;
179 			a = (pte & ARM_L2_L_FRAME) +
180 			    (va & ARM_L2_L_OFFSET & ARM_L2_S_FRAME);
181 		} else {
182 			if (kd->vmst->hdr.mmuformat == MINIDUMP_MMU_FORMAT_V4 &&
183 			    (pte & ARM_L2_TYPE_MASK) == ARM_L2_TYPE_T) {
184 				_kvm_err(kd, kd->program,
185 				    "_arm_minidump_kvatop: pte not supported");
186 				goto invalid;
187 			}
188 			/* 4K page */
189 			offset = va & ARM_L2_S_OFFSET;
190 			a = pte & ARM_L2_S_FRAME;
191 		}
192 
193 		ofs = _kvm_pt_find(kd, a);
194 		if (ofs == -1) {
195 			_kvm_err(kd, kd->program, "_arm_minidump_kvatop: "
196 			    "physical address 0x%jx not in minidump",
197 			    (uintmax_t)a);
198 			goto invalid;
199 		}
200 
201 		*pa = ofs + offset;
202 		return (ARM_PAGE_SIZE - offset);
203 	} else
204 		_kvm_err(kd, kd->program, "_arm_minidump_kvatop: virtual "
205 		    "address 0x%jx not minidumped", (uintmax_t)va);
206 
207 invalid:
208 	_kvm_err(kd, 0, "invalid address (0x%jx)", (uintmax_t)va);
209 	return (0);
210 }
211 
212 struct kvm_arch kvm_arm_minidump = {
213 	.ka_probe = _arm_minidump_probe,
214 	.ka_initvtop = _arm_minidump_initvtop,
215 	.ka_freevtop = _arm_minidump_freevtop,
216 	.ka_kvatop = _arm_minidump_kvatop,
217 	.ka_native = _arm_native,
218 };
219 
220 KVM_ARCH(kvm_arm_minidump);
221