| 1 | /* Native-dependent code for FreeBSD/amd64. |
| 2 | |
| 3 | Copyright (C) 2003, 2004, 2007 Free Software Foundation, Inc. |
| 4 | |
| 5 | This file is part of GDB. |
| 6 | |
| 7 | This program is free software; you can redistribute it and/or modify |
| 8 | it under the terms of the GNU General Public License as published by |
| 9 | the Free Software Foundation; either version 2 of the License, or |
| 10 | (at your option) any later version. |
| 11 | |
| 12 | This program is distributed in the hope that it will be useful, |
| 13 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | GNU General Public License for more details. |
| 16 | |
| 17 | You should have received a copy of the GNU General Public License |
| 18 | along with this program; if not, write to the Free Software |
| 19 | Foundation, Inc., 51 Franklin Street, Fifth Floor, |
| 20 | Boston, MA 02110-1301, USA. */ |
| 21 | |
| 22 | #include "defs.h" |
| 23 | #include "inferior.h" |
| 24 | #include "regcache.h" |
| 25 | #include "target.h" |
| 26 | |
| 27 | #include "gdb_assert.h" |
| 28 | #include <signal.h> |
| 29 | #include <stddef.h> |
| 30 | #include <sys/types.h> |
| 31 | #include <sys/ptrace.h> |
| 32 | #include <sys/sysctl.h> |
| 33 | #include <machine/reg.h> |
| 34 | |
| 35 | #include "fbsd-nat.h" |
| 36 | #include "amd64-tdep.h" |
| 37 | #include "amd64-nat.h" |
| 38 | \f |
| 39 | |
| 40 | /* Offset in `struct reg' where MEMBER is stored. */ |
| 41 | #define REG_OFFSET(member) offsetof (struct reg, member) |
| 42 | |
| 43 | /* At amd64fbsd64_r_reg_offset[REGNUM] you'll find the offset in |
| 44 | `struct reg' location where the GDB register REGNUM is stored. |
| 45 | Unsupported registers are marked with `-1'. */ |
| 46 | static int amd64fbsd64_r_reg_offset[] = |
| 47 | { |
| 48 | REG_OFFSET (r_rax), |
| 49 | REG_OFFSET (r_rbx), |
| 50 | REG_OFFSET (r_rcx), |
| 51 | REG_OFFSET (r_rdx), |
| 52 | REG_OFFSET (r_rsi), |
| 53 | REG_OFFSET (r_rdi), |
| 54 | REG_OFFSET (r_rbp), |
| 55 | REG_OFFSET (r_rsp), |
| 56 | REG_OFFSET (r_r8), |
| 57 | REG_OFFSET (r_r9), |
| 58 | REG_OFFSET (r_r10), |
| 59 | REG_OFFSET (r_r11), |
| 60 | REG_OFFSET (r_r12), |
| 61 | REG_OFFSET (r_r13), |
| 62 | REG_OFFSET (r_r14), |
| 63 | REG_OFFSET (r_r15), |
| 64 | REG_OFFSET (r_rip), |
| 65 | REG_OFFSET (r_rflags), |
| 66 | REG_OFFSET (r_cs), |
| 67 | REG_OFFSET (r_ss), |
| 68 | -1, |
| 69 | -1, |
| 70 | -1, |
| 71 | -1 |
| 72 | }; |
| 73 | \f |
| 74 | |
| 75 | /* Mapping between the general-purpose registers in FreeBSD/amd64 |
| 76 | `struct reg' format and GDB's register cache layout for |
| 77 | FreeBSD/i386. |
| 78 | |
| 79 | Note that most FreeBSD/amd64 registers are 64-bit, while the |
| 80 | FreeBSD/i386 registers are all 32-bit, but since we're |
| 81 | little-endian we get away with that. */ |
| 82 | |
| 83 | /* From <machine/reg.h>. */ |
| 84 | static int amd64fbsd32_r_reg_offset[I386_NUM_GREGS] = |
| 85 | { |
| 86 | 14 * 8, 13 * 8, /* %eax, %ecx */ |
| 87 | 12 * 8, 11 * 8, /* %edx, %ebx */ |
| 88 | 20 * 8, 10 * 8, /* %esp, %ebp */ |
| 89 | 9 * 8, 8 * 8, /* %esi, %edi */ |
| 90 | 17 * 8, 19 * 8, /* %eip, %eflags */ |
| 91 | 18 * 8, 21 * 8, /* %cs, %ss */ |
| 92 | -1, -1, -1, -1 /* %ds, %es, %fs, %gs */ |
| 93 | }; |
| 94 | \f |
| 95 | |
| 96 | /* Support for debugging kernel virtual memory images. */ |
| 97 | |
| 98 | #include <sys/types.h> |
| 99 | #include <machine/pcb.h> |
| 100 | |
| 101 | #include "bsd-kvm.h" |
| 102 | |
| 103 | static int |
| 104 | amd64fbsd_supply_pcb (struct regcache *regcache, struct pcb *pcb) |
| 105 | { |
| 106 | /* The following is true for FreeBSD 5.2: |
| 107 | |
| 108 | The pcb contains %rip, %rbx, %rsp, %rbp, %r12, %r13, %r14, %r15, |
| 109 | %ds, %es, %fs and %gs. This accounts for all callee-saved |
| 110 | registers specified by the psABI and then some. Here %esp |
| 111 | contains the stack pointer at the point just after the call to |
| 112 | cpu_switch(). From this information we reconstruct the register |
| 113 | state as it would like when we just returned from cpu_switch(). */ |
| 114 | |
| 115 | /* The stack pointer shouldn't be zero. */ |
| 116 | if (pcb->pcb_rsp == 0) |
| 117 | return 0; |
| 118 | |
| 119 | pcb->pcb_rsp += 8; |
| 120 | regcache_raw_supply (regcache, AMD64_RIP_REGNUM, &pcb->pcb_rip); |
| 121 | regcache_raw_supply (regcache, AMD64_RBX_REGNUM, &pcb->pcb_rbx); |
| 122 | regcache_raw_supply (regcache, AMD64_RSP_REGNUM, &pcb->pcb_rsp); |
| 123 | regcache_raw_supply (regcache, AMD64_RBP_REGNUM, &pcb->pcb_rbp); |
| 124 | regcache_raw_supply (regcache, 12, &pcb->pcb_r12); |
| 125 | regcache_raw_supply (regcache, 13, &pcb->pcb_r13); |
| 126 | regcache_raw_supply (regcache, 14, &pcb->pcb_r14); |
| 127 | regcache_raw_supply (regcache, 15, &pcb->pcb_r15); |
| 128 | regcache_raw_supply (regcache, AMD64_DS_REGNUM, &pcb->pcb_ds); |
| 129 | regcache_raw_supply (regcache, AMD64_ES_REGNUM, &pcb->pcb_es); |
| 130 | regcache_raw_supply (regcache, AMD64_FS_REGNUM, &pcb->pcb_fs); |
| 131 | regcache_raw_supply (regcache, AMD64_GS_REGNUM, &pcb->pcb_gs); |
| 132 | |
| 133 | return 1; |
| 134 | } |
| 135 | \f |
| 136 | |
| 137 | /* Provide a prototype to silence -Wmissing-prototypes. */ |
| 138 | void _initialize_amd64fbsd_nat (void); |
| 139 | |
| 140 | void |
| 141 | _initialize_amd64fbsd_nat (void) |
| 142 | { |
| 143 | struct target_ops *t; |
| 144 | int offset; |
| 145 | |
| 146 | amd64_native_gregset32_reg_offset = amd64fbsd32_r_reg_offset; |
| 147 | amd64_native_gregset64_reg_offset = amd64fbsd64_r_reg_offset; |
| 148 | |
| 149 | /* Add some extra features to the common *BSD/i386 target. */ |
| 150 | t = amd64bsd_target (); |
| 151 | t->to_pid_to_exec_file = fbsd_pid_to_exec_file; |
| 152 | t->to_find_memory_regions = fbsd_find_memory_regions; |
| 153 | t->to_make_corefile_notes = fbsd_make_corefile_notes; |
| 154 | add_target (t); |
| 155 | |
| 156 | /* Support debugging kernel virtual memory images. */ |
| 157 | bsd_kvm_add_target (amd64fbsd_supply_pcb); |
| 158 | |
| 159 | /* To support the recognition of signal handlers, i386bsd-tdep.c |
| 160 | hardcodes some constants. Inclusion of this file means that we |
| 161 | are compiling a native debugger, which means that we can use the |
| 162 | system header files and sysctl(3) to get at the relevant |
| 163 | information. */ |
| 164 | |
| 165 | #define SC_REG_OFFSET amd64fbsd_sc_reg_offset |
| 166 | |
| 167 | /* We only check the program counter, stack pointer and frame |
| 168 | pointer since these members of `struct sigcontext' are essential |
| 169 | for providing backtraces. */ |
| 170 | |
| 171 | #define SC_RIP_OFFSET SC_REG_OFFSET[AMD64_RIP_REGNUM] |
| 172 | #define SC_RSP_OFFSET SC_REG_OFFSET[AMD64_RSP_REGNUM] |
| 173 | #define SC_RBP_OFFSET SC_REG_OFFSET[AMD64_RBP_REGNUM] |
| 174 | |
| 175 | /* Override the default value for the offset of the program counter |
| 176 | in the sigcontext structure. */ |
| 177 | offset = offsetof (struct sigcontext, sc_rip); |
| 178 | |
| 179 | if (SC_RIP_OFFSET != offset) |
| 180 | { |
| 181 | warning (_("\ |
| 182 | offsetof (struct sigcontext, sc_rip) yields %d instead of %d.\n\ |
| 183 | Please report this to <bug-gdb@gnu.org>."), |
| 184 | offset, SC_RIP_OFFSET); |
| 185 | } |
| 186 | |
| 187 | SC_RIP_OFFSET = offset; |
| 188 | |
| 189 | /* Likewise for the stack pointer. */ |
| 190 | offset = offsetof (struct sigcontext, sc_rsp); |
| 191 | |
| 192 | if (SC_RSP_OFFSET != offset) |
| 193 | { |
| 194 | warning (_("\ |
| 195 | offsetof (struct sigcontext, sc_rsp) yields %d instead of %d.\n\ |
| 196 | Please report this to <bug-gdb@gnu.org>."), |
| 197 | offset, SC_RSP_OFFSET); |
| 198 | } |
| 199 | |
| 200 | SC_RSP_OFFSET = offset; |
| 201 | |
| 202 | /* And the frame pointer. */ |
| 203 | offset = offsetof (struct sigcontext, sc_rbp); |
| 204 | |
| 205 | if (SC_RBP_OFFSET != offset) |
| 206 | { |
| 207 | warning (_("\ |
| 208 | offsetof (struct sigcontext, sc_rbp) yields %d instead of %d.\n\ |
| 209 | Please report this to <bug-gdb@gnu.org>."), |
| 210 | offset, SC_RBP_OFFSET); |
| 211 | } |
| 212 | |
| 213 | SC_RBP_OFFSET = offset; |
| 214 | |
| 215 | /* FreeBSD provides a kern.ps_strings sysctl that we can use to |
| 216 | locate the sigtramp. That way we can still recognize a sigtramp |
| 217 | if its location is changed in a new kernel. Of course this is |
| 218 | still based on the assumption that the sigtramp is placed |
| 219 | directly under the location where the program arguments and |
| 220 | environment can be found. */ |
| 221 | { |
| 222 | int mib[2]; |
| 223 | long ps_strings; |
| 224 | size_t len; |
| 225 | |
| 226 | mib[0] = CTL_KERN; |
| 227 | mib[1] = KERN_PS_STRINGS; |
| 228 | len = sizeof (ps_strings); |
| 229 | if (sysctl (mib, 2, &ps_strings, &len, NULL, 0) == 0) |
| 230 | { |
| 231 | amd64fbsd_sigtramp_start_addr = ps_strings - 32; |
| 232 | amd64fbsd_sigtramp_end_addr = ps_strings; |
| 233 | } |
| 234 | } |
| 235 | } |