| 1 | /* Low level interface to i386 running the GNU Hurd. |
| 2 | |
| 3 | Copyright (C) 1992-2019 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 3 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, see <http://www.gnu.org/licenses/>. */ |
| 19 | |
| 20 | /* Include this first, to pick up the <mach.h> 'thread_info' diversion. */ |
| 21 | #include "gnu-nat.h" |
| 22 | |
| 23 | /* Mach/Hurd headers are not yet ready for C++ compilation. */ |
| 24 | extern "C" |
| 25 | { |
| 26 | #include <mach.h> |
| 27 | #include <mach_error.h> |
| 28 | #include <mach/message.h> |
| 29 | #include <mach/exception.h> |
| 30 | } |
| 31 | |
| 32 | #include "defs.h" |
| 33 | #include "x86-nat.h" |
| 34 | #include "inferior.h" |
| 35 | #include "floatformat.h" |
| 36 | #include "regcache.h" |
| 37 | |
| 38 | #include "i386-tdep.h" |
| 39 | |
| 40 | #include "inf-child.h" |
| 41 | #include "i387-tdep.h" |
| 42 | |
| 43 | /* Offset to the thread_state_t location where REG is stored. */ |
| 44 | #define REG_OFFSET(reg) offsetof (struct i386_thread_state, reg) |
| 45 | |
| 46 | /* At REG_OFFSET[N] is the offset to the thread_state_t location where |
| 47 | the GDB register N is stored. */ |
| 48 | static int reg_offset[] = |
| 49 | { |
| 50 | REG_OFFSET (eax), REG_OFFSET (ecx), REG_OFFSET (edx), REG_OFFSET (ebx), |
| 51 | REG_OFFSET (uesp), REG_OFFSET (ebp), REG_OFFSET (esi), REG_OFFSET (edi), |
| 52 | REG_OFFSET (eip), REG_OFFSET (efl), REG_OFFSET (cs), REG_OFFSET (ss), |
| 53 | REG_OFFSET (ds), REG_OFFSET (es), REG_OFFSET (fs), REG_OFFSET (gs) |
| 54 | }; |
| 55 | |
| 56 | #define REG_ADDR(state, regnum) ((char *)(state) + reg_offset[regnum]) |
| 57 | |
| 58 | \f |
| 59 | |
| 60 | /* The i386 GNU Hurd target. */ |
| 61 | |
| 62 | #ifdef i386_DEBUG_STATE |
| 63 | using gnu_base_target = x86_nat_target<gnu_nat_target>; |
| 64 | #else |
| 65 | using gnu_base_target = gnu_nat_target; |
| 66 | #endif |
| 67 | |
| 68 | struct i386_gnu_nat_target final : public gnu_base_target |
| 69 | { |
| 70 | void fetch_registers (struct regcache *, int) override; |
| 71 | void store_registers (struct regcache *, int) override; |
| 72 | }; |
| 73 | |
| 74 | static i386_gnu_nat_target the_i386_gnu_nat_target; |
| 75 | |
| 76 | /* Get the whole floating-point state of THREAD and record the values |
| 77 | of the corresponding (pseudo) registers. */ |
| 78 | |
| 79 | static void |
| 80 | fetch_fpregs (struct regcache *regcache, struct proc *thread) |
| 81 | { |
| 82 | mach_msg_type_number_t count = i386_FLOAT_STATE_COUNT; |
| 83 | struct i386_float_state state; |
| 84 | kern_return_t err; |
| 85 | |
| 86 | err = thread_get_state (thread->port, i386_FLOAT_STATE, |
| 87 | (thread_state_t) &state, &count); |
| 88 | if (err) |
| 89 | { |
| 90 | warning (_("Couldn't fetch floating-point state from %s"), |
| 91 | proc_string (thread)); |
| 92 | return; |
| 93 | } |
| 94 | |
| 95 | if (!state.initialized) |
| 96 | { |
| 97 | /* The floating-point state isn't initialized. */ |
| 98 | i387_supply_fsave (regcache, -1, NULL); |
| 99 | } |
| 100 | else |
| 101 | { |
| 102 | /* Supply the floating-point registers. */ |
| 103 | i387_supply_fsave (regcache, -1, state.hw_state); |
| 104 | } |
| 105 | } |
| 106 | |
| 107 | /* Fetch register REGNO, or all regs if REGNO is -1. */ |
| 108 | void |
| 109 | i386_gnu_nat_target::fetch_registers (struct regcache *regcache, int regno) |
| 110 | { |
| 111 | struct proc *thread; |
| 112 | ptid_t ptid = regcache->ptid (); |
| 113 | |
| 114 | /* Make sure we know about new threads. */ |
| 115 | inf_update_procs (gnu_current_inf); |
| 116 | |
| 117 | thread = inf_tid_to_thread (gnu_current_inf, ptid.lwp ()); |
| 118 | if (!thread) |
| 119 | error (_("Can't fetch registers from thread %s: No such thread"), |
| 120 | target_pid_to_str (ptid).c_str ()); |
| 121 | |
| 122 | if (regno < I386_NUM_GREGS || regno == -1) |
| 123 | { |
| 124 | thread_state_t state; |
| 125 | |
| 126 | /* This does the dirty work for us. */ |
| 127 | state = proc_get_state (thread, 0); |
| 128 | if (!state) |
| 129 | { |
| 130 | warning (_("Couldn't fetch registers from %s"), |
| 131 | proc_string (thread)); |
| 132 | return; |
| 133 | } |
| 134 | |
| 135 | if (regno == -1) |
| 136 | { |
| 137 | int i; |
| 138 | |
| 139 | proc_debug (thread, "fetching all register"); |
| 140 | |
| 141 | for (i = 0; i < I386_NUM_GREGS; i++) |
| 142 | regcache->raw_supply (i, REG_ADDR (state, i)); |
| 143 | thread->fetched_regs = ~0; |
| 144 | } |
| 145 | else |
| 146 | { |
| 147 | proc_debug (thread, "fetching register %s", |
| 148 | gdbarch_register_name (regcache->arch (), |
| 149 | regno)); |
| 150 | |
| 151 | regcache->raw_supply (regno, REG_ADDR (state, regno)); |
| 152 | thread->fetched_regs |= (1 << regno); |
| 153 | } |
| 154 | } |
| 155 | |
| 156 | if (regno >= I386_NUM_GREGS || regno == -1) |
| 157 | { |
| 158 | proc_debug (thread, "fetching floating-point registers"); |
| 159 | |
| 160 | fetch_fpregs (regcache, thread); |
| 161 | } |
| 162 | } |
| 163 | \f |
| 164 | |
| 165 | /* Store the whole floating-point state into THREAD using information |
| 166 | from the corresponding (pseudo) registers. */ |
| 167 | static void |
| 168 | store_fpregs (const struct regcache *regcache, struct proc *thread, int regno) |
| 169 | { |
| 170 | mach_msg_type_number_t count = i386_FLOAT_STATE_COUNT; |
| 171 | struct i386_float_state state; |
| 172 | kern_return_t err; |
| 173 | |
| 174 | err = thread_get_state (thread->port, i386_FLOAT_STATE, |
| 175 | (thread_state_t) &state, &count); |
| 176 | if (err) |
| 177 | { |
| 178 | warning (_("Couldn't fetch floating-point state from %s"), |
| 179 | proc_string (thread)); |
| 180 | return; |
| 181 | } |
| 182 | |
| 183 | /* FIXME: kettenis/2001-07-15: Is this right? Should we somehow |
| 184 | take into account DEPRECATED_REGISTER_VALID like the old code did? */ |
| 185 | i387_collect_fsave (regcache, regno, state.hw_state); |
| 186 | |
| 187 | err = thread_set_state (thread->port, i386_FLOAT_STATE, |
| 188 | (thread_state_t) &state, i386_FLOAT_STATE_COUNT); |
| 189 | if (err) |
| 190 | { |
| 191 | warning (_("Couldn't store floating-point state into %s"), |
| 192 | proc_string (thread)); |
| 193 | return; |
| 194 | } |
| 195 | } |
| 196 | |
| 197 | /* Store at least register REGNO, or all regs if REGNO == -1. */ |
| 198 | void |
| 199 | i386_gnu_nat_target::store_registers (struct regcache *regcache, int regno) |
| 200 | { |
| 201 | struct proc *thread; |
| 202 | struct gdbarch *gdbarch = regcache->arch (); |
| 203 | ptid_t ptid = regcache->ptid (); |
| 204 | |
| 205 | /* Make sure we know about new threads. */ |
| 206 | inf_update_procs (gnu_current_inf); |
| 207 | |
| 208 | thread = inf_tid_to_thread (gnu_current_inf, ptid.lwp ()); |
| 209 | if (!thread) |
| 210 | error (_("Couldn't store registers into thread %s: No such thread"), |
| 211 | target_pid_to_str (ptid).c_str ()); |
| 212 | |
| 213 | if (regno < I386_NUM_GREGS || regno == -1) |
| 214 | { |
| 215 | thread_state_t state; |
| 216 | thread_state_data_t old_state; |
| 217 | int was_aborted = thread->aborted; |
| 218 | int was_valid = thread->state_valid; |
| 219 | int trace; |
| 220 | |
| 221 | if (!was_aborted && was_valid) |
| 222 | memcpy (&old_state, &thread->state, sizeof (old_state)); |
| 223 | |
| 224 | state = proc_get_state (thread, 1); |
| 225 | if (!state) |
| 226 | { |
| 227 | warning (_("Couldn't store registers into %s"), |
| 228 | proc_string (thread)); |
| 229 | return; |
| 230 | } |
| 231 | |
| 232 | /* Save the T bit. We might try to restore the %eflags register |
| 233 | below, but changing the T bit would seriously confuse GDB. */ |
| 234 | trace = ((struct i386_thread_state *)state)->efl & 0x100; |
| 235 | |
| 236 | if (!was_aborted && was_valid) |
| 237 | /* See which registers have changed after aborting the thread. */ |
| 238 | { |
| 239 | int check_regno; |
| 240 | |
| 241 | for (check_regno = 0; check_regno < I386_NUM_GREGS; check_regno++) |
| 242 | if ((thread->fetched_regs & (1 << check_regno)) |
| 243 | && memcpy (REG_ADDR (&old_state, check_regno), |
| 244 | REG_ADDR (state, check_regno), |
| 245 | register_size (gdbarch, check_regno))) |
| 246 | /* Register CHECK_REGNO has changed! Ack! */ |
| 247 | { |
| 248 | warning (_("Register %s changed after the thread was aborted"), |
| 249 | gdbarch_register_name (gdbarch, check_regno)); |
| 250 | if (regno >= 0 && regno != check_regno) |
| 251 | /* Update GDB's copy of the register. */ |
| 252 | regcache->raw_supply (check_regno, |
| 253 | REG_ADDR (state, check_regno)); |
| 254 | else |
| 255 | warning (_("... also writing this register! " |
| 256 | "Suspicious...")); |
| 257 | } |
| 258 | } |
| 259 | |
| 260 | if (regno == -1) |
| 261 | { |
| 262 | int i; |
| 263 | |
| 264 | proc_debug (thread, "storing all registers"); |
| 265 | |
| 266 | for (i = 0; i < I386_NUM_GREGS; i++) |
| 267 | if (REG_VALID == regcache->get_register_status (i)) |
| 268 | regcache->raw_collect (i, REG_ADDR (state, i)); |
| 269 | } |
| 270 | else |
| 271 | { |
| 272 | proc_debug (thread, "storing register %s", |
| 273 | gdbarch_register_name (gdbarch, regno)); |
| 274 | |
| 275 | gdb_assert (REG_VALID == regcache->get_register_status (regno)); |
| 276 | regcache->raw_collect (regno, REG_ADDR (state, regno)); |
| 277 | } |
| 278 | |
| 279 | /* Restore the T bit. */ |
| 280 | ((struct i386_thread_state *)state)->efl &= ~0x100; |
| 281 | ((struct i386_thread_state *)state)->efl |= trace; |
| 282 | } |
| 283 | |
| 284 | if (regno >= I386_NUM_GREGS || regno == -1) |
| 285 | { |
| 286 | proc_debug (thread, "storing floating-point registers"); |
| 287 | |
| 288 | store_fpregs (regcache, thread, regno); |
| 289 | } |
| 290 | } |
| 291 | |
| 292 | \f |
| 293 | /* Support for debug registers. */ |
| 294 | |
| 295 | #ifdef i386_DEBUG_STATE |
| 296 | /* Get debug registers for thread THREAD. */ |
| 297 | |
| 298 | static void |
| 299 | i386_gnu_dr_get (struct i386_debug_state *regs, struct proc *thread) |
| 300 | { |
| 301 | mach_msg_type_number_t count = i386_DEBUG_STATE_COUNT; |
| 302 | kern_return_t err; |
| 303 | |
| 304 | err = thread_get_state (thread->port, i386_DEBUG_STATE, |
| 305 | (thread_state_t) regs, &count); |
| 306 | if (err != 0 || count != i386_DEBUG_STATE_COUNT) |
| 307 | warning (_("Couldn't fetch debug state from %s"), |
| 308 | proc_string (thread)); |
| 309 | } |
| 310 | |
| 311 | /* Set debug registers for thread THREAD. */ |
| 312 | |
| 313 | static void |
| 314 | i386_gnu_dr_set (const struct i386_debug_state *regs, struct proc *thread) |
| 315 | { |
| 316 | kern_return_t err; |
| 317 | |
| 318 | err = thread_set_state (thread->port, i386_DEBUG_STATE, |
| 319 | (thread_state_t) regs, i386_DEBUG_STATE_COUNT); |
| 320 | if (err != 0) |
| 321 | warning (_("Couldn't store debug state into %s"), |
| 322 | proc_string (thread)); |
| 323 | } |
| 324 | |
| 325 | /* Set DR_CONTROL in THREAD. */ |
| 326 | |
| 327 | static void |
| 328 | i386_gnu_dr_set_control_one (struct proc *thread, void *arg) |
| 329 | { |
| 330 | unsigned long *control = (unsigned long *) arg; |
| 331 | struct i386_debug_state regs; |
| 332 | |
| 333 | i386_gnu_dr_get (®s, thread); |
| 334 | regs.dr[DR_CONTROL] = *control; |
| 335 | i386_gnu_dr_set (®s, thread); |
| 336 | } |
| 337 | |
| 338 | /* Set DR_CONTROL to CONTROL in all threads. */ |
| 339 | |
| 340 | static void |
| 341 | i386_gnu_dr_set_control (unsigned long control) |
| 342 | { |
| 343 | inf_update_procs (gnu_current_inf); |
| 344 | inf_threads (gnu_current_inf, i386_gnu_dr_set_control_one, &control); |
| 345 | } |
| 346 | |
| 347 | /* Parameters to set a debugging address. */ |
| 348 | |
| 349 | struct reg_addr |
| 350 | { |
| 351 | int regnum; /* Register number (zero based). */ |
| 352 | CORE_ADDR addr; /* Address. */ |
| 353 | }; |
| 354 | |
| 355 | /* Set address REGNUM (zero based) to ADDR in THREAD. */ |
| 356 | |
| 357 | static void |
| 358 | i386_gnu_dr_set_addr_one (struct proc *thread, void *arg) |
| 359 | { |
| 360 | struct reg_addr *reg_addr = (struct reg_addr *) arg; |
| 361 | struct i386_debug_state regs; |
| 362 | |
| 363 | i386_gnu_dr_get (®s, thread); |
| 364 | regs.dr[reg_addr->regnum] = reg_addr->addr; |
| 365 | i386_gnu_dr_set (®s, thread); |
| 366 | } |
| 367 | |
| 368 | /* Set address REGNUM (zero based) to ADDR in all threads. */ |
| 369 | |
| 370 | static void |
| 371 | i386_gnu_dr_set_addr (int regnum, CORE_ADDR addr) |
| 372 | { |
| 373 | struct reg_addr reg_addr; |
| 374 | |
| 375 | gdb_assert (DR_FIRSTADDR <= regnum && regnum <= DR_LASTADDR); |
| 376 | |
| 377 | reg_addr.regnum = regnum; |
| 378 | reg_addr.addr = addr; |
| 379 | |
| 380 | inf_update_procs (gnu_current_inf); |
| 381 | inf_threads (gnu_current_inf, i386_gnu_dr_set_addr_one, ®_addr); |
| 382 | } |
| 383 | |
| 384 | /* Get debug register REGNUM value from only the one LWP of PTID. */ |
| 385 | |
| 386 | static unsigned long |
| 387 | i386_gnu_dr_get_reg (ptid_t ptid, int regnum) |
| 388 | { |
| 389 | struct i386_debug_state regs; |
| 390 | struct proc *thread; |
| 391 | |
| 392 | /* Make sure we know about new threads. */ |
| 393 | inf_update_procs (gnu_current_inf); |
| 394 | |
| 395 | thread = inf_tid_to_thread (gnu_current_inf, ptid.lwp ()); |
| 396 | i386_gnu_dr_get (®s, thread); |
| 397 | |
| 398 | return regs.dr[regnum]; |
| 399 | } |
| 400 | |
| 401 | /* Return the inferior's debug register REGNUM. */ |
| 402 | |
| 403 | static CORE_ADDR |
| 404 | i386_gnu_dr_get_addr (int regnum) |
| 405 | { |
| 406 | gdb_assert (DR_FIRSTADDR <= regnum && regnum <= DR_LASTADDR); |
| 407 | |
| 408 | return i386_gnu_dr_get_reg (inferior_ptid, regnum); |
| 409 | } |
| 410 | |
| 411 | /* Get DR_STATUS from only the one thread of INFERIOR_PTID. */ |
| 412 | |
| 413 | static unsigned long |
| 414 | i386_gnu_dr_get_status (void) |
| 415 | { |
| 416 | return i386_gnu_dr_get_reg (inferior_ptid, DR_STATUS); |
| 417 | } |
| 418 | |
| 419 | /* Return the inferior's DR7 debug control register. */ |
| 420 | |
| 421 | static unsigned long |
| 422 | i386_gnu_dr_get_control (void) |
| 423 | { |
| 424 | return i386_gnu_dr_get_reg (inferior_ptid, DR_CONTROL); |
| 425 | } |
| 426 | #endif /* i386_DEBUG_STATE */ |
| 427 | |
| 428 | void |
| 429 | _initialize_i386gnu_nat (void) |
| 430 | { |
| 431 | #ifdef i386_DEBUG_STATE |
| 432 | x86_dr_low.set_control = i386_gnu_dr_set_control; |
| 433 | gdb_assert (DR_FIRSTADDR == 0 && DR_LASTADDR < i386_DEBUG_STATE_COUNT); |
| 434 | x86_dr_low.set_addr = i386_gnu_dr_set_addr; |
| 435 | x86_dr_low.get_addr = i386_gnu_dr_get_addr; |
| 436 | x86_dr_low.get_status = i386_gnu_dr_get_status; |
| 437 | x86_dr_low.get_control = i386_gnu_dr_get_control; |
| 438 | x86_set_debug_register_length (4); |
| 439 | #endif /* i386_DEBUG_STATE */ |
| 440 | |
| 441 | /* Register the target. */ |
| 442 | add_inf_child_target (&the_i386_gnu_nat_target); |
| 443 | } |