1 /* GNU/Linux/x86-64 specific low level interface, for the remote server
3 Copyright (C) 2002, 2004, 2005, 2006, 2007, 2008, 2009
4 Free Software Foundation, Inc.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
24 #include "linux-low.h"
28 #include "gdb_proc_service.h"
30 /* NOTE: gdb_proc_service.h may include linux/elf.h.
31 We need Elf32_Phdr. If we don't get linux/elf.h we could include
32 elf.h like linux-ppc-low.c does. */
34 /* Defined in auto-generated file reg-i386-linux.c. */
35 void init_registers_i386_linux (void);
36 /* Defined in auto-generated file reg-x86-64-linux.c. */
37 void init_registers_x86_64_linux (void);
40 #include <sys/procfs.h>
41 #include <sys/ptrace.h>
43 #ifndef PTRACE_GET_THREAD_AREA
44 #define PTRACE_GET_THREAD_AREA 25
47 /* This definition comes from prctl.h, but some kernels may not have it. */
48 #ifndef PTRACE_ARCH_PRCTL
49 #define PTRACE_ARCH_PRCTL 30
52 /* The following definitions come from prctl.h, but may be absent
53 for certain configurations. */
55 #define ARCH_SET_GS 0x1001
56 #define ARCH_SET_FS 0x1002
57 #define ARCH_GET_FS 0x1003
58 #define ARCH_GET_GS 0x1004
61 /* Per-process arch-specific data we want to keep. */
63 struct arch_process_info
65 struct i386_debug_reg_state debug_reg_state;
68 /* Per-thread arch-specific data we want to keep. */
72 /* Non-zero if our copy differs from what's recorded in the thread. */
73 int debug_registers_changed;
78 /* Mapping between the general-purpose registers in `struct user'
79 format and GDB's register array layout.
80 Note that the transfer layout uses 64-bit regs. */
81 static /*const*/ int i386_regmap[] =
83 RAX * 8, RCX * 8, RDX * 8, RBX * 8,
84 RSP * 8, RBP * 8, RSI * 8, RDI * 8,
85 RIP * 8, EFLAGS * 8, CS * 8, SS * 8,
86 DS * 8, ES * 8, FS * 8, GS * 8
89 #define I386_NUM_REGS (sizeof (i386_regmap) / sizeof (i386_regmap[0]))
91 /* So code below doesn't have to care, i386 or amd64. */
92 #define ORIG_EAX ORIG_RAX
94 static const int x86_64_regmap[] =
96 RAX * 8, RBX * 8, RCX * 8, RDX * 8,
97 RSI * 8, RDI * 8, RBP * 8, RSP * 8,
98 R8 * 8, R9 * 8, R10 * 8, R11 * 8,
99 R12 * 8, R13 * 8, R14 * 8, R15 * 8,
100 RIP * 8, EFLAGS * 8, CS * 8, SS * 8,
101 DS * 8, ES * 8, FS * 8, GS * 8,
102 -1, -1, -1, -1, -1, -1, -1, -1,
103 -1, -1, -1, -1, -1, -1, -1, -1,
104 -1, -1, -1, -1, -1, -1, -1, -1,
105 -1, -1, -1, -1, -1, -1, -1, -1, -1,
109 #define X86_64_NUM_REGS (sizeof (x86_64_regmap) / sizeof (x86_64_regmap[0]))
111 #else /* ! __x86_64__ */
113 /* Mapping between the general-purpose registers in `struct user'
114 format and GDB's register array layout. */
115 static /*const*/ int i386_regmap[] =
117 EAX * 4, ECX * 4, EDX * 4, EBX * 4,
118 UESP * 4, EBP * 4, ESI * 4, EDI * 4,
119 EIP * 4, EFL * 4, CS * 4, SS * 4,
120 DS * 4, ES * 4, FS * 4, GS * 4
123 #define I386_NUM_REGS (sizeof (i386_regmap) / sizeof (i386_regmap[0]))
127 /* Called by libthread_db. */
130 ps_get_thread_area (const struct ps_prochandle *ph,
131 lwpid_t lwpid, int idx, void **base)
134 int use_64bit = register_size (0) == 8;
141 if (ptrace (PTRACE_ARCH_PRCTL, lwpid, base, ARCH_GET_FS) == 0)
145 if (ptrace (PTRACE_ARCH_PRCTL, lwpid, base, ARCH_GET_GS) == 0)
156 unsigned int desc[4];
158 if (ptrace (PTRACE_GET_THREAD_AREA, lwpid,
159 (void *) (intptr_t) idx, (unsigned long) &desc) < 0)
162 *(int *)base = desc[1];
168 i386_cannot_store_register (int regno)
170 return regno >= I386_NUM_REGS;
174 i386_cannot_fetch_register (int regno)
176 return regno >= I386_NUM_REGS;
180 x86_fill_gregset (void *buf)
185 if (register_size (0) == 8)
187 for (i = 0; i < X86_64_NUM_REGS; i++)
188 if (x86_64_regmap[i] != -1)
189 collect_register (i, ((char *) buf) + x86_64_regmap[i]);
194 for (i = 0; i < I386_NUM_REGS; i++)
195 collect_register (i, ((char *) buf) + i386_regmap[i]);
197 collect_register_by_name ("orig_eax", ((char *) buf) + ORIG_EAX * 4);
201 x86_store_gregset (const void *buf)
206 if (register_size (0) == 8)
208 for (i = 0; i < X86_64_NUM_REGS; i++)
209 if (x86_64_regmap[i] != -1)
210 supply_register (i, ((char *) buf) + x86_64_regmap[i]);
215 for (i = 0; i < I386_NUM_REGS; i++)
216 supply_register (i, ((char *) buf) + i386_regmap[i]);
218 supply_register_by_name ("orig_eax", ((char *) buf) + ORIG_EAX * 4);
222 x86_fill_fpregset (void *buf)
225 i387_cache_to_fxsave (buf);
227 i387_cache_to_fsave (buf);
232 x86_store_fpregset (const void *buf)
235 i387_fxsave_to_cache (buf);
237 i387_fsave_to_cache (buf);
244 x86_fill_fpxregset (void *buf)
246 i387_cache_to_fxsave (buf);
250 x86_store_fpxregset (const void *buf)
252 i387_fxsave_to_cache (buf);
257 /* ??? The non-biarch i386 case stores all the i387 regs twice.
258 Once in i387_.*fsave.* and once in i387_.*fxsave.*.
259 This is, presumably, to handle the case where PTRACE_[GS]ETFPXREGS
260 doesn't work. IWBN to avoid the duplication in the case where it
261 does work. Maybe the arch_setup routine could check whether it works
262 and update target_regsets accordingly, maybe by moving target_regsets
263 to linux_target_ops and set the right one there, rather than having to
264 modify the target_regsets global. */
266 struct regset_info target_regsets[] =
268 #ifdef HAVE_PTRACE_GETREGS
269 { PTRACE_GETREGS, PTRACE_SETREGS, sizeof (elf_gregset_t),
271 x86_fill_gregset, x86_store_gregset },
273 # ifdef HAVE_PTRACE_GETFPXREGS
274 { PTRACE_GETFPXREGS, PTRACE_SETFPXREGS, sizeof (elf_fpxregset_t),
276 x86_fill_fpxregset, x86_store_fpxregset },
279 { PTRACE_GETFPREGS, PTRACE_SETFPREGS, sizeof (elf_fpregset_t),
281 x86_fill_fpregset, x86_store_fpregset },
282 #endif /* HAVE_PTRACE_GETREGS */
283 { 0, 0, -1, -1, NULL, NULL }
289 int use_64bit = register_size (0) == 8;
294 collect_register_by_name ("rip", &pc);
295 return (CORE_ADDR) pc;
300 collect_register_by_name ("eip", &pc);
301 return (CORE_ADDR) pc;
306 x86_set_pc (CORE_ADDR pc)
308 int use_64bit = register_size (0) == 8;
312 unsigned long newpc = pc;
313 supply_register_by_name ("rip", &newpc);
317 unsigned int newpc = pc;
318 supply_register_by_name ("eip", &newpc);
322 static const unsigned char x86_breakpoint[] = { 0xCC };
323 #define x86_breakpoint_len 1
326 x86_breakpoint_at (CORE_ADDR pc)
330 read_inferior_memory (pc, &c, 1);
337 /* Support for debug registers. */
340 x86_linux_dr_get (ptid_t ptid, int regnum)
345 tid = ptid_get_lwp (ptid);
348 value = ptrace (PTRACE_PEEKUSER, tid,
349 offsetof (struct user, u_debugreg[regnum]), 0);
351 error ("Couldn't read debug register");
357 x86_linux_dr_set (ptid_t ptid, int regnum, unsigned long value)
361 tid = ptid_get_lwp (ptid);
364 ptrace (PTRACE_POKEUSER, tid,
365 offsetof (struct user, u_debugreg[regnum]), value);
367 error ("Couldn't write debug register");
370 /* Update the inferior's debug register REGNUM from STATE. */
373 i386_dr_low_set_addr (const struct i386_debug_reg_state *state, int regnum)
375 struct inferior_list_entry *lp;
377 /* Only need to update the threads of this process. */
378 int pid = pid_of (get_thread_lwp (current_inferior));
380 if (! (regnum >= 0 && regnum <= DR_LASTADDR - DR_FIRSTADDR))
381 fatal ("Invalid debug register %d", regnum);
383 addr = state->dr_mirror[regnum];
385 for (lp = all_lwps.head; lp; lp = lp->next)
387 struct lwp_info *lwp = (struct lwp_info *) lp;
389 /* The actual update is done later, we just mark that the register
391 if (pid_of (lwp) == pid)
392 lwp->arch_private->debug_registers_changed = 1;
396 /* Update the inferior's DR7 debug control register from STATE. */
399 i386_dr_low_set_control (const struct i386_debug_reg_state *state)
401 struct inferior_list_entry *lp;
402 /* Only need to update the threads of this process. */
403 int pid = pid_of (get_thread_lwp (current_inferior));
405 for (lp = all_lwps.head; lp; lp = lp->next)
407 struct lwp_info *lwp = (struct lwp_info *) lp;
409 /* The actual update is done later, we just mark that the register
411 if (pid_of (lwp) == pid)
412 lwp->arch_private->debug_registers_changed = 1;
416 /* Get the value of the DR6 debug status register from the inferior
417 and record it in STATE. */
420 i386_dr_low_get_status (struct i386_debug_reg_state *state)
422 struct lwp_info *lwp = get_thread_lwp (current_inferior);
423 ptid_t ptid = ptid_of (lwp);
425 state->dr_status_mirror = x86_linux_dr_get (ptid, DR_STATUS);
428 /* Watchpoint support. */
431 x86_insert_point (char type, CORE_ADDR addr, int len)
433 struct process_info *proc = current_process ();
439 return i386_low_insert_watchpoint (&proc->private->arch_private->debug_reg_state,
448 x86_remove_point (char type, CORE_ADDR addr, int len)
450 struct process_info *proc = current_process ();
456 return i386_low_remove_watchpoint (&proc->private->arch_private->debug_reg_state,
465 x86_stopped_by_watchpoint (void)
467 struct process_info *proc = current_process ();
468 return i386_low_stopped_by_watchpoint (&proc->private->arch_private->debug_reg_state);
472 x86_stopped_data_address (void)
474 struct process_info *proc = current_process ();
476 if (i386_low_stopped_data_address (&proc->private->arch_private->debug_reg_state,
482 /* Called when a new process is created. */
484 static struct arch_process_info *
485 x86_linux_new_process (void)
487 struct arch_process_info *info = xcalloc (1, sizeof (*info));
489 i386_low_init_dregs (&info->debug_reg_state);
494 /* Called when a new thread is detected. */
496 static struct arch_lwp_info *
497 x86_linux_new_thread (void)
499 struct arch_lwp_info *info = xcalloc (1, sizeof (*info));
501 info->debug_registers_changed = 1;
506 /* Called when resuming a thread.
507 If the debug regs have changed, update the thread's copies. */
510 x86_linux_prepare_to_resume (struct lwp_info *lwp)
512 if (lwp->arch_private->debug_registers_changed)
515 ptid_t ptid = ptid_of (lwp);
516 int pid = ptid_get_pid (ptid);
517 struct process_info *proc = find_process_pid (pid);
518 struct i386_debug_reg_state *state = &proc->private->arch_private->debug_reg_state;
520 for (i = DR_FIRSTADDR; i <= DR_LASTADDR; i++)
521 x86_linux_dr_set (ptid, i, state->dr_mirror[i]);
523 x86_linux_dr_set (ptid, DR_CONTROL, state->dr_control_mirror);
525 lwp->arch_private->debug_registers_changed = 0;
529 /* When GDBSERVER is built as a 64-bit application on linux, the
530 PTRACE_GETSIGINFO data is always presented in 64-bit layout. Since
531 debugging a 32-bit inferior with a 64-bit GDBSERVER should look the same
532 as debugging it with a 32-bit GDBSERVER, we do the 32-bit <-> 64-bit
533 conversion in-place ourselves. */
535 /* These types below (compat_*) define a siginfo type that is layout
536 compatible with the siginfo type exported by the 32-bit userspace
541 typedef int compat_int_t;
542 typedef unsigned int compat_uptr_t;
544 typedef int compat_time_t;
545 typedef int compat_timer_t;
546 typedef int compat_clock_t;
548 struct compat_timeval
550 compat_time_t tv_sec;
554 typedef union compat_sigval
556 compat_int_t sival_int;
557 compat_uptr_t sival_ptr;
560 typedef struct compat_siginfo
568 int _pad[((128 / sizeof (int)) - 3)];
577 /* POSIX.1b timers */
582 compat_sigval_t _sigval;
585 /* POSIX.1b signals */
590 compat_sigval_t _sigval;
599 compat_clock_t _utime;
600 compat_clock_t _stime;
603 /* SIGILL, SIGFPE, SIGSEGV, SIGBUS */
618 #define cpt_si_pid _sifields._kill._pid
619 #define cpt_si_uid _sifields._kill._uid
620 #define cpt_si_timerid _sifields._timer._tid
621 #define cpt_si_overrun _sifields._timer._overrun
622 #define cpt_si_status _sifields._sigchld._status
623 #define cpt_si_utime _sifields._sigchld._utime
624 #define cpt_si_stime _sifields._sigchld._stime
625 #define cpt_si_ptr _sifields._rt._sigval.sival_ptr
626 #define cpt_si_addr _sifields._sigfault._addr
627 #define cpt_si_band _sifields._sigpoll._band
628 #define cpt_si_fd _sifields._sigpoll._fd
630 /* glibc at least up to 2.3.2 doesn't have si_timerid, si_overrun.
631 In their place is si_timer1,si_timer2. */
633 #define si_timerid si_timer1
636 #define si_overrun si_timer2
640 compat_siginfo_from_siginfo (compat_siginfo_t *to, siginfo_t *from)
642 memset (to, 0, sizeof (*to));
644 to->si_signo = from->si_signo;
645 to->si_errno = from->si_errno;
646 to->si_code = from->si_code;
650 to->cpt_si_ptr = (intptr_t) from->si_ptr;
652 else if (to->si_code == SI_USER)
654 to->cpt_si_pid = from->si_pid;
655 to->cpt_si_uid = from->si_uid;
657 else if (to->si_code == SI_TIMER)
659 to->cpt_si_timerid = from->si_timerid;
660 to->cpt_si_overrun = from->si_overrun;
661 to->cpt_si_ptr = (intptr_t) from->si_ptr;
665 switch (to->si_signo)
668 to->cpt_si_pid = from->si_pid;
669 to->cpt_si_uid = from->si_uid;
670 to->cpt_si_status = from->si_status;
671 to->cpt_si_utime = from->si_utime;
672 to->cpt_si_stime = from->si_stime;
678 to->cpt_si_addr = (intptr_t) from->si_addr;
681 to->cpt_si_band = from->si_band;
682 to->cpt_si_fd = from->si_fd;
685 to->cpt_si_pid = from->si_pid;
686 to->cpt_si_uid = from->si_uid;
687 to->cpt_si_ptr = (intptr_t) from->si_ptr;
694 siginfo_from_compat_siginfo (siginfo_t *to, compat_siginfo_t *from)
696 memset (to, 0, sizeof (*to));
698 to->si_signo = from->si_signo;
699 to->si_errno = from->si_errno;
700 to->si_code = from->si_code;
704 to->si_ptr = (void *) (intptr_t) from->cpt_si_ptr;
706 else if (to->si_code == SI_USER)
708 to->si_pid = from->cpt_si_pid;
709 to->si_uid = from->cpt_si_uid;
711 else if (to->si_code == SI_TIMER)
713 to->si_timerid = from->cpt_si_timerid;
714 to->si_overrun = from->cpt_si_overrun;
715 to->si_ptr = (void *) (intptr_t) from->cpt_si_ptr;
719 switch (to->si_signo)
722 to->si_pid = from->cpt_si_pid;
723 to->si_uid = from->cpt_si_uid;
724 to->si_status = from->cpt_si_status;
725 to->si_utime = from->cpt_si_utime;
726 to->si_stime = from->cpt_si_stime;
732 to->si_addr = (void *) (intptr_t) from->cpt_si_addr;
735 to->si_band = from->cpt_si_band;
736 to->si_fd = from->cpt_si_fd;
739 to->si_pid = from->cpt_si_pid;
740 to->si_uid = from->cpt_si_uid;
741 to->si_ptr = (void* ) (intptr_t) from->cpt_si_ptr;
747 #endif /* __x86_64__ */
749 /* Convert a native/host siginfo object, into/from the siginfo in the
750 layout of the inferiors' architecture. Returns true if any
751 conversion was done; false otherwise. If DIRECTION is 1, then copy
752 from INF to NATIVE. If DIRECTION is 0, copy from NATIVE to
756 x86_siginfo_fixup (struct siginfo *native, void *inf, int direction)
759 /* Is the inferior 32-bit? If so, then fixup the siginfo object. */
760 if (register_size (0) == 4)
762 if (sizeof (struct siginfo) != sizeof (compat_siginfo_t))
763 fatal ("unexpected difference in siginfo");
766 compat_siginfo_from_siginfo ((struct compat_siginfo *) inf, native);
768 siginfo_from_compat_siginfo (native, (struct compat_siginfo *) inf);
777 /* Initialize gdbserver for the architecture of the inferior. */
780 x86_arch_setup (void)
783 int pid = pid_of (get_thread_lwp (current_inferior));
784 char *file = linux_child_pid_to_exec_file (pid);
785 int use_64bit = elf_64_file_p (file);
791 /* This can only happen if /proc/<pid>/exe is unreadable,
792 but "that can't happen" if we've gotten this far.
793 Fall through and assume this is a 32-bit program. */
797 init_registers_x86_64_linux ();
799 /* Amd64 doesn't have HAVE_LINUX_USRREGS. */
800 the_low_target.num_regs = -1;
801 the_low_target.regmap = NULL;
802 the_low_target.cannot_fetch_register = NULL;
803 the_low_target.cannot_store_register = NULL;
805 /* Amd64 has 16 xmm regs. */
806 num_xmm_registers = 16;
812 /* Ok we have a 32-bit inferior. */
814 init_registers_i386_linux ();
816 the_low_target.num_regs = I386_NUM_REGS;
817 the_low_target.regmap = i386_regmap;
818 the_low_target.cannot_fetch_register = i386_cannot_fetch_register;
819 the_low_target.cannot_store_register = i386_cannot_store_register;
821 /* I386 has 8 xmm regs. */
822 num_xmm_registers = 8;
825 /* This is initialized assuming an amd64 target.
826 x86_arch_setup will correct it for i386 or amd64 targets. */
828 struct linux_target_ops the_low_target =
844 x86_stopped_by_watchpoint,
845 x86_stopped_data_address,
846 /* collect_ptrace_register/supply_ptrace_register are not needed in the
847 native i386 case (no registers smaller than an xfer unit), and are not
848 used in the biarch case (HAVE_LINUX_USRREGS is not defined). */
851 /* need to fix up i386 siginfo if host is amd64 */
853 x86_linux_new_process,
854 x86_linux_new_thread,
855 x86_linux_prepare_to_resume