1 /* $NetBSD: kvm_aarch64.c,v 1.8 2018/12/19 11:02:21 mrg Exp $ */ 2 3 /*- 4 * Copyright (c) 2014, 2018 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Matt Thomas of 3am Software Foundry. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #include <sys/param.h> 33 #include <sys/proc.h> 34 #include <sys/stat.h> 35 #include <sys/kcore.h> 36 #include <sys/types.h> 37 #include <unistd.h> 38 #include <nlist.h> 39 #include <kvm.h> 40 41 #include <machine/kcore.h> 42 #include <machine/pte.h> 43 #include <machine/vmparam.h> 44 45 #include <limits.h> 46 #include <db.h> 47 #include <stdlib.h> 48 49 #include "kvm_private.h" 50 51 __RCSID("$NetBSD: kvm_aarch64.c,v 1.8 2018/12/19 11:02:21 mrg Exp $"); 52 53 /*ARGSUSED*/ 54 void 55 _kvm_freevtop(kvm_t *kd) 56 { 57 return; 58 } 59 60 /*ARGSUSED*/ 61 int 62 _kvm_initvtop(kvm_t *kd) 63 { 64 return (0); 65 } 66 67 int 68 _kvm_kvatop(kvm_t *kd, vaddr_t va, paddr_t *pa) 69 { 70 if (ISALIVE(kd)) { 71 _kvm_err(kd, 0, "vatop called in live kernel!"); 72 return(0); 73 } 74 75 if ((va & AARCH64_KSEG_MASK) != AARCH64_KSEG_START) { 76 /* 77 * Bogus address (not in KV space): punt. 78 */ 79 _kvm_err(kd, 0, "invalid kernel virtual address"); 80 lose: 81 *pa = -1; 82 return 0; 83 } 84 85 const cpu_kcore_hdr_t * const cpu_kh = kd->cpu_data; 86 const uint64_t tg1 = cpu_kh->kh_tcr1 & TCR_TG1; 87 const u_int t1siz = __SHIFTOUT(cpu_kh->kh_tcr1, TCR_T1SZ); 88 const u_int inputsz = 64 - t1siz; 89 90 /* 91 * Real kernel virtual address: do the translation. 92 */ 93 94 u_int page_shift; 95 96 switch (tg1) { 97 case TCR_TG1_4KB: 98 page_shift = 12; 99 break; 100 case TCR_TG1_16KB: 101 page_shift = 14; 102 break; 103 case TCR_TG1_64KB: 104 page_shift = 16; 105 break; 106 default: 107 goto lose; 108 } 109 110 const size_t page_size = 1 << page_shift; 111 const uint64_t page_mask = __BITS(page_shift - 1, 0); 112 const uint64_t page_addr = __BITS(47, page_shift); 113 const u_int pte_shift = page_shift - 3; 114 115 /* how many levels of page tables do we have? */ 116 u_int levels = howmany(inputsz - page_shift, pte_shift); 117 118 /* restrict va to the valid VA bits */ 119 va &= __BITS(inputsz - 1, 0); 120 121 u_int addr_shift = page_shift + (levels - 1) * pte_shift; 122 123 /* clear out the unused low bits of the table address */ 124 paddr_t pte_addr = cpu_kh->kh_ttbr1 & TTBR_BADDR; 125 126 for (;;) { 127 pt_entry_t pte; 128 129 /* now index into the pte table */ 130 const uint64_t idx_mask = __BITS(addr_shift + pte_shift - 1, 131 addr_shift); 132 pte_addr += 8 * __SHIFTOUT(va, idx_mask); 133 134 /* Find and read the PTE. */ 135 if (_kvm_pread(kd, kd->pmfd, &pte, sizeof(pte), 136 _kvm_pa2off(kd, pte_addr)) != sizeof(pte)) { 137 _kvm_syserr(kd, 0, "could not read pte"); 138 goto lose; 139 } 140 141 /* Find and read the L2 PTE. */ 142 if ((pte & LX_VALID) == 0) { 143 _kvm_err(kd, 0, "invalid translation (invalid pte)"); 144 goto lose; 145 } 146 147 if ((pte & LX_TYPE) == LX_TYPE_BLK) { 148 const size_t blk_size = 1 << addr_shift; 149 const uint64_t blk_mask = __BITS(addr_shift - 1, 0); 150 151 *pa = (pte & page_addr & ~blk_mask) | (va & blk_mask); 152 return blk_size - (va & blk_mask); 153 } 154 if (--levels == 0) { 155 *pa = (pte & page_addr) | (va & page_mask); 156 return page_size - (va & page_mask); 157 } 158 159 /* 160 * Read next level of page table 161 */ 162 163 pte_addr = pte & page_addr; 164 addr_shift -= pte_shift; 165 } 166 } 167 168 /* 169 * Translate a physical address to a file-offset in the crash dump. 170 */ 171 off_t 172 _kvm_pa2off(kvm_t *kd, paddr_t pa) 173 { 174 const cpu_kcore_hdr_t * const cpu_kh = kd->cpu_data; 175 off_t off = 0; 176 177 for (const phys_ram_seg_t *ramsegs = cpu_kh->kh_ramsegs; 178 ramsegs->size != 0; ramsegs++) { 179 if (pa >= ramsegs->start 180 && pa < ramsegs->start + ramsegs->size) { 181 off += pa - ramsegs->start; 182 break; 183 } 184 off += ramsegs->size; 185 } 186 187 return kd->dump_off + off; 188 } 189 190 /* 191 * Machine-dependent initialization for ALL open kvm descriptors, 192 * not just those for a kernel crash dump. Some architectures 193 * have to deal with these NOT being constants! (i.e. m68k) 194 */ 195 int 196 _kvm_mdopen(kvm_t *kd) 197 { 198 199 kd->usrstack = USRSTACK; 200 kd->min_uva = VM_MIN_ADDRESS; 201 kd->max_uva = VM_MAXUSER_ADDRESS; 202 203 return (0); 204 } 205