1 /* GNU/Linux/x86-64 specific low level interface, for the remote server
3 Copyright (C) 2002, 2004, 2005, 2006, 2007, 2008, 2009, 2010
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 /* Defined in auto-generated file reg-i386-linux.c. */
31 void init_registers_i386_linux (void);
32 /* Defined in auto-generated file reg-x86-64-linux.c. */
33 void init_registers_x86_64_linux (void);
36 #include <sys/procfs.h>
37 #include <sys/ptrace.h>
39 #ifndef PTRACE_GET_THREAD_AREA
40 #define PTRACE_GET_THREAD_AREA 25
43 /* This definition comes from prctl.h, but some kernels may not have it. */
44 #ifndef PTRACE_ARCH_PRCTL
45 #define PTRACE_ARCH_PRCTL 30
48 /* The following definitions come from prctl.h, but may be absent
49 for certain configurations. */
51 #define ARCH_SET_GS 0x1001
52 #define ARCH_SET_FS 0x1002
53 #define ARCH_GET_FS 0x1003
54 #define ARCH_GET_GS 0x1004
57 /* Per-process arch-specific data we want to keep. */
59 struct arch_process_info
61 struct i386_debug_reg_state debug_reg_state
;
64 /* Per-thread arch-specific data we want to keep. */
68 /* Non-zero if our copy differs from what's recorded in the thread. */
69 int debug_registers_changed
;
74 /* Mapping between the general-purpose registers in `struct user'
75 format and GDB's register array layout.
76 Note that the transfer layout uses 64-bit regs. */
77 static /*const*/ int i386_regmap
[] =
79 RAX
* 8, RCX
* 8, RDX
* 8, RBX
* 8,
80 RSP
* 8, RBP
* 8, RSI
* 8, RDI
* 8,
81 RIP
* 8, EFLAGS
* 8, CS
* 8, SS
* 8,
82 DS
* 8, ES
* 8, FS
* 8, GS
* 8
85 #define I386_NUM_REGS (sizeof (i386_regmap) / sizeof (i386_regmap[0]))
87 /* So code below doesn't have to care, i386 or amd64. */
88 #define ORIG_EAX ORIG_RAX
90 static const int x86_64_regmap
[] =
92 RAX
* 8, RBX
* 8, RCX
* 8, RDX
* 8,
93 RSI
* 8, RDI
* 8, RBP
* 8, RSP
* 8,
94 R8
* 8, R9
* 8, R10
* 8, R11
* 8,
95 R12
* 8, R13
* 8, R14
* 8, R15
* 8,
96 RIP
* 8, EFLAGS
* 8, CS
* 8, SS
* 8,
97 DS
* 8, ES
* 8, FS
* 8, GS
* 8,
98 -1, -1, -1, -1, -1, -1, -1, -1,
99 -1, -1, -1, -1, -1, -1, -1, -1,
100 -1, -1, -1, -1, -1, -1, -1, -1,
101 -1, -1, -1, -1, -1, -1, -1, -1, -1,
105 #define X86_64_NUM_REGS (sizeof (x86_64_regmap) / sizeof (x86_64_regmap[0]))
107 #else /* ! __x86_64__ */
109 /* Mapping between the general-purpose registers in `struct user'
110 format and GDB's register array layout. */
111 static /*const*/ int i386_regmap
[] =
113 EAX
* 4, ECX
* 4, EDX
* 4, EBX
* 4,
114 UESP
* 4, EBP
* 4, ESI
* 4, EDI
* 4,
115 EIP
* 4, EFL
* 4, CS
* 4, SS
* 4,
116 DS
* 4, ES
* 4, FS
* 4, GS
* 4
119 #define I386_NUM_REGS (sizeof (i386_regmap) / sizeof (i386_regmap[0]))
123 /* Called by libthread_db. */
126 ps_get_thread_area (const struct ps_prochandle
*ph
,
127 lwpid_t lwpid
, int idx
, void **base
)
130 int use_64bit
= register_size (0) == 8;
137 if (ptrace (PTRACE_ARCH_PRCTL
, lwpid
, base
, ARCH_GET_FS
) == 0)
141 if (ptrace (PTRACE_ARCH_PRCTL
, lwpid
, base
, ARCH_GET_GS
) == 0)
152 unsigned int desc
[4];
154 if (ptrace (PTRACE_GET_THREAD_AREA
, lwpid
,
155 (void *) (intptr_t) idx
, (unsigned long) &desc
) < 0)
158 *(int *)base
= desc
[1];
164 i386_cannot_store_register (int regno
)
166 return regno
>= I386_NUM_REGS
;
170 i386_cannot_fetch_register (int regno
)
172 return regno
>= I386_NUM_REGS
;
176 x86_fill_gregset (struct regcache
*regcache
, void *buf
)
181 if (register_size (0) == 8)
183 for (i
= 0; i
< X86_64_NUM_REGS
; i
++)
184 if (x86_64_regmap
[i
] != -1)
185 collect_register (regcache
, i
, ((char *) buf
) + x86_64_regmap
[i
]);
190 for (i
= 0; i
< I386_NUM_REGS
; i
++)
191 collect_register (regcache
, i
, ((char *) buf
) + i386_regmap
[i
]);
193 collect_register_by_name (regcache
, "orig_eax",
194 ((char *) buf
) + ORIG_EAX
* 4);
198 x86_store_gregset (struct regcache
*regcache
, const void *buf
)
203 if (register_size (0) == 8)
205 for (i
= 0; i
< X86_64_NUM_REGS
; i
++)
206 if (x86_64_regmap
[i
] != -1)
207 supply_register (regcache
, i
, ((char *) buf
) + x86_64_regmap
[i
]);
212 for (i
= 0; i
< I386_NUM_REGS
; i
++)
213 supply_register (regcache
, i
, ((char *) buf
) + i386_regmap
[i
]);
215 supply_register_by_name (regcache
, "orig_eax",
216 ((char *) buf
) + ORIG_EAX
* 4);
220 x86_fill_fpregset (struct regcache
*regcache
, void *buf
)
223 i387_cache_to_fxsave (regcache
, buf
);
225 i387_cache_to_fsave (regcache
, buf
);
230 x86_store_fpregset (struct regcache
*regcache
, const void *buf
)
233 i387_fxsave_to_cache (regcache
, buf
);
235 i387_fsave_to_cache (regcache
, buf
);
242 x86_fill_fpxregset (struct regcache
*regcache
, void *buf
)
244 i387_cache_to_fxsave (regcache
, buf
);
248 x86_store_fpxregset (struct regcache
*regcache
, const void *buf
)
250 i387_fxsave_to_cache (regcache
, buf
);
255 /* ??? The non-biarch i386 case stores all the i387 regs twice.
256 Once in i387_.*fsave.* and once in i387_.*fxsave.*.
257 This is, presumably, to handle the case where PTRACE_[GS]ETFPXREGS
258 doesn't work. IWBN to avoid the duplication in the case where it
259 does work. Maybe the arch_setup routine could check whether it works
260 and update target_regsets accordingly, maybe by moving target_regsets
261 to linux_target_ops and set the right one there, rather than having to
262 modify the target_regsets global. */
264 struct regset_info target_regsets
[] =
266 #ifdef HAVE_PTRACE_GETREGS
267 { PTRACE_GETREGS
, PTRACE_SETREGS
, sizeof (elf_gregset_t
),
269 x86_fill_gregset
, x86_store_gregset
},
271 # ifdef HAVE_PTRACE_GETFPXREGS
272 { PTRACE_GETFPXREGS
, PTRACE_SETFPXREGS
, sizeof (elf_fpxregset_t
),
274 x86_fill_fpxregset
, x86_store_fpxregset
},
277 { PTRACE_GETFPREGS
, PTRACE_SETFPREGS
, sizeof (elf_fpregset_t
),
279 x86_fill_fpregset
, x86_store_fpregset
},
280 #endif /* HAVE_PTRACE_GETREGS */
281 { 0, 0, -1, -1, NULL
, NULL
}
285 x86_get_pc (struct regcache
*regcache
)
287 int use_64bit
= register_size (0) == 8;
292 collect_register_by_name (regcache
, "rip", &pc
);
293 return (CORE_ADDR
) pc
;
298 collect_register_by_name (regcache
, "eip", &pc
);
299 return (CORE_ADDR
) pc
;
304 x86_set_pc (struct regcache
*regcache
, CORE_ADDR pc
)
306 int use_64bit
= register_size (0) == 8;
310 unsigned long newpc
= pc
;
311 supply_register_by_name (regcache
, "rip", &newpc
);
315 unsigned int newpc
= pc
;
316 supply_register_by_name (regcache
, "eip", &newpc
);
320 static const unsigned char x86_breakpoint
[] = { 0xCC };
321 #define x86_breakpoint_len 1
324 x86_breakpoint_at (CORE_ADDR pc
)
328 read_inferior_memory (pc
, &c
, 1);
335 /* Support for debug registers. */
338 x86_linux_dr_get (ptid_t ptid
, int regnum
)
343 tid
= ptid_get_lwp (ptid
);
346 value
= ptrace (PTRACE_PEEKUSER
, tid
,
347 offsetof (struct user
, u_debugreg
[regnum
]), 0);
349 error ("Couldn't read debug register");
355 x86_linux_dr_set (ptid_t ptid
, int regnum
, unsigned long value
)
359 tid
= ptid_get_lwp (ptid
);
362 ptrace (PTRACE_POKEUSER
, tid
,
363 offsetof (struct user
, u_debugreg
[regnum
]), value
);
365 error ("Couldn't write debug register");
368 /* Update the inferior's debug register REGNUM from STATE. */
371 i386_dr_low_set_addr (const struct i386_debug_reg_state
*state
, int regnum
)
373 struct inferior_list_entry
*lp
;
375 /* Only need to update the threads of this process. */
376 int pid
= pid_of (get_thread_lwp (current_inferior
));
378 if (! (regnum
>= 0 && regnum
<= DR_LASTADDR
- DR_FIRSTADDR
))
379 fatal ("Invalid debug register %d", regnum
);
381 addr
= state
->dr_mirror
[regnum
];
383 for (lp
= all_lwps
.head
; lp
; lp
= lp
->next
)
385 struct lwp_info
*lwp
= (struct lwp_info
*) lp
;
387 /* The actual update is done later, we just mark that the register
389 if (pid_of (lwp
) == pid
)
390 lwp
->arch_private
->debug_registers_changed
= 1;
394 /* Update the inferior's DR7 debug control register from STATE. */
397 i386_dr_low_set_control (const struct i386_debug_reg_state
*state
)
399 struct inferior_list_entry
*lp
;
400 /* Only need to update the threads of this process. */
401 int pid
= pid_of (get_thread_lwp (current_inferior
));
403 for (lp
= all_lwps
.head
; lp
; lp
= lp
->next
)
405 struct lwp_info
*lwp
= (struct lwp_info
*) lp
;
407 /* The actual update is done later, we just mark that the register
409 if (pid_of (lwp
) == pid
)
410 lwp
->arch_private
->debug_registers_changed
= 1;
414 /* Get the value of the DR6 debug status register from the inferior
415 and record it in STATE. */
418 i386_dr_low_get_status (struct i386_debug_reg_state
*state
)
420 struct lwp_info
*lwp
= get_thread_lwp (current_inferior
);
421 ptid_t ptid
= ptid_of (lwp
);
423 state
->dr_status_mirror
= x86_linux_dr_get (ptid
, DR_STATUS
);
426 /* Watchpoint support. */
429 x86_insert_point (char type
, CORE_ADDR addr
, int len
)
431 struct process_info
*proc
= current_process ();
437 return i386_low_insert_watchpoint (&proc
->private->arch_private
->debug_reg_state
,
446 x86_remove_point (char type
, CORE_ADDR addr
, int len
)
448 struct process_info
*proc
= current_process ();
454 return i386_low_remove_watchpoint (&proc
->private->arch_private
->debug_reg_state
,
463 x86_stopped_by_watchpoint (void)
465 struct process_info
*proc
= current_process ();
466 return i386_low_stopped_by_watchpoint (&proc
->private->arch_private
->debug_reg_state
);
470 x86_stopped_data_address (void)
472 struct process_info
*proc
= current_process ();
474 if (i386_low_stopped_data_address (&proc
->private->arch_private
->debug_reg_state
,
480 /* Called when a new process is created. */
482 static struct arch_process_info
*
483 x86_linux_new_process (void)
485 struct arch_process_info
*info
= xcalloc (1, sizeof (*info
));
487 i386_low_init_dregs (&info
->debug_reg_state
);
492 /* Called when a new thread is detected. */
494 static struct arch_lwp_info
*
495 x86_linux_new_thread (void)
497 struct arch_lwp_info
*info
= xcalloc (1, sizeof (*info
));
499 info
->debug_registers_changed
= 1;
504 /* Called when resuming a thread.
505 If the debug regs have changed, update the thread's copies. */
508 x86_linux_prepare_to_resume (struct lwp_info
*lwp
)
510 if (lwp
->arch_private
->debug_registers_changed
)
513 ptid_t ptid
= ptid_of (lwp
);
514 int pid
= ptid_get_pid (ptid
);
515 struct process_info
*proc
= find_process_pid (pid
);
516 struct i386_debug_reg_state
*state
= &proc
->private->arch_private
->debug_reg_state
;
518 for (i
= DR_FIRSTADDR
; i
<= DR_LASTADDR
; i
++)
519 x86_linux_dr_set (ptid
, i
, state
->dr_mirror
[i
]);
521 x86_linux_dr_set (ptid
, DR_CONTROL
, state
->dr_control_mirror
);
523 lwp
->arch_private
->debug_registers_changed
= 0;
527 /* When GDBSERVER is built as a 64-bit application on linux, the
528 PTRACE_GETSIGINFO data is always presented in 64-bit layout. Since
529 debugging a 32-bit inferior with a 64-bit GDBSERVER should look the same
530 as debugging it with a 32-bit GDBSERVER, we do the 32-bit <-> 64-bit
531 conversion in-place ourselves. */
533 /* These types below (compat_*) define a siginfo type that is layout
534 compatible with the siginfo type exported by the 32-bit userspace
539 typedef int compat_int_t
;
540 typedef unsigned int compat_uptr_t
;
542 typedef int compat_time_t
;
543 typedef int compat_timer_t
;
544 typedef int compat_clock_t
;
546 struct compat_timeval
548 compat_time_t tv_sec
;
552 typedef union compat_sigval
554 compat_int_t sival_int
;
555 compat_uptr_t sival_ptr
;
558 typedef struct compat_siginfo
566 int _pad
[((128 / sizeof (int)) - 3)];
575 /* POSIX.1b timers */
580 compat_sigval_t _sigval
;
583 /* POSIX.1b signals */
588 compat_sigval_t _sigval
;
597 compat_clock_t _utime
;
598 compat_clock_t _stime
;
601 /* SIGILL, SIGFPE, SIGSEGV, SIGBUS */
616 #define cpt_si_pid _sifields._kill._pid
617 #define cpt_si_uid _sifields._kill._uid
618 #define cpt_si_timerid _sifields._timer._tid
619 #define cpt_si_overrun _sifields._timer._overrun
620 #define cpt_si_status _sifields._sigchld._status
621 #define cpt_si_utime _sifields._sigchld._utime
622 #define cpt_si_stime _sifields._sigchld._stime
623 #define cpt_si_ptr _sifields._rt._sigval.sival_ptr
624 #define cpt_si_addr _sifields._sigfault._addr
625 #define cpt_si_band _sifields._sigpoll._band
626 #define cpt_si_fd _sifields._sigpoll._fd
628 /* glibc at least up to 2.3.2 doesn't have si_timerid, si_overrun.
629 In their place is si_timer1,si_timer2. */
631 #define si_timerid si_timer1
634 #define si_overrun si_timer2
638 compat_siginfo_from_siginfo (compat_siginfo_t
*to
, siginfo_t
*from
)
640 memset (to
, 0, sizeof (*to
));
642 to
->si_signo
= from
->si_signo
;
643 to
->si_errno
= from
->si_errno
;
644 to
->si_code
= from
->si_code
;
648 to
->cpt_si_ptr
= (intptr_t) from
->si_ptr
;
650 else if (to
->si_code
== SI_USER
)
652 to
->cpt_si_pid
= from
->si_pid
;
653 to
->cpt_si_uid
= from
->si_uid
;
655 else if (to
->si_code
== SI_TIMER
)
657 to
->cpt_si_timerid
= from
->si_timerid
;
658 to
->cpt_si_overrun
= from
->si_overrun
;
659 to
->cpt_si_ptr
= (intptr_t) from
->si_ptr
;
663 switch (to
->si_signo
)
666 to
->cpt_si_pid
= from
->si_pid
;
667 to
->cpt_si_uid
= from
->si_uid
;
668 to
->cpt_si_status
= from
->si_status
;
669 to
->cpt_si_utime
= from
->si_utime
;
670 to
->cpt_si_stime
= from
->si_stime
;
676 to
->cpt_si_addr
= (intptr_t) from
->si_addr
;
679 to
->cpt_si_band
= from
->si_band
;
680 to
->cpt_si_fd
= from
->si_fd
;
683 to
->cpt_si_pid
= from
->si_pid
;
684 to
->cpt_si_uid
= from
->si_uid
;
685 to
->cpt_si_ptr
= (intptr_t) from
->si_ptr
;
692 siginfo_from_compat_siginfo (siginfo_t
*to
, compat_siginfo_t
*from
)
694 memset (to
, 0, sizeof (*to
));
696 to
->si_signo
= from
->si_signo
;
697 to
->si_errno
= from
->si_errno
;
698 to
->si_code
= from
->si_code
;
702 to
->si_ptr
= (void *) (intptr_t) from
->cpt_si_ptr
;
704 else if (to
->si_code
== SI_USER
)
706 to
->si_pid
= from
->cpt_si_pid
;
707 to
->si_uid
= from
->cpt_si_uid
;
709 else if (to
->si_code
== SI_TIMER
)
711 to
->si_timerid
= from
->cpt_si_timerid
;
712 to
->si_overrun
= from
->cpt_si_overrun
;
713 to
->si_ptr
= (void *) (intptr_t) from
->cpt_si_ptr
;
717 switch (to
->si_signo
)
720 to
->si_pid
= from
->cpt_si_pid
;
721 to
->si_uid
= from
->cpt_si_uid
;
722 to
->si_status
= from
->cpt_si_status
;
723 to
->si_utime
= from
->cpt_si_utime
;
724 to
->si_stime
= from
->cpt_si_stime
;
730 to
->si_addr
= (void *) (intptr_t) from
->cpt_si_addr
;
733 to
->si_band
= from
->cpt_si_band
;
734 to
->si_fd
= from
->cpt_si_fd
;
737 to
->si_pid
= from
->cpt_si_pid
;
738 to
->si_uid
= from
->cpt_si_uid
;
739 to
->si_ptr
= (void* ) (intptr_t) from
->cpt_si_ptr
;
745 #endif /* __x86_64__ */
747 /* Convert a native/host siginfo object, into/from the siginfo in the
748 layout of the inferiors' architecture. Returns true if any
749 conversion was done; false otherwise. If DIRECTION is 1, then copy
750 from INF to NATIVE. If DIRECTION is 0, copy from NATIVE to
754 x86_siginfo_fixup (struct siginfo
*native
, void *inf
, int direction
)
757 /* Is the inferior 32-bit? If so, then fixup the siginfo object. */
758 if (register_size (0) == 4)
760 if (sizeof (struct siginfo
) != sizeof (compat_siginfo_t
))
761 fatal ("unexpected difference in siginfo");
764 compat_siginfo_from_siginfo ((struct compat_siginfo
*) inf
, native
);
766 siginfo_from_compat_siginfo (native
, (struct compat_siginfo
*) inf
);
775 /* Initialize gdbserver for the architecture of the inferior. */
778 x86_arch_setup (void)
781 int pid
= pid_of (get_thread_lwp (current_inferior
));
782 char *file
= linux_child_pid_to_exec_file (pid
);
783 int use_64bit
= elf_64_file_p (file
);
789 /* This can only happen if /proc/<pid>/exe is unreadable,
790 but "that can't happen" if we've gotten this far.
791 Fall through and assume this is a 32-bit program. */
795 init_registers_x86_64_linux ();
797 /* Amd64 doesn't have HAVE_LINUX_USRREGS. */
798 the_low_target
.num_regs
= -1;
799 the_low_target
.regmap
= NULL
;
800 the_low_target
.cannot_fetch_register
= NULL
;
801 the_low_target
.cannot_store_register
= NULL
;
803 /* Amd64 has 16 xmm regs. */
804 num_xmm_registers
= 16;
810 /* Ok we have a 32-bit inferior. */
812 init_registers_i386_linux ();
814 the_low_target
.num_regs
= I386_NUM_REGS
;
815 the_low_target
.regmap
= i386_regmap
;
816 the_low_target
.cannot_fetch_register
= i386_cannot_fetch_register
;
817 the_low_target
.cannot_store_register
= i386_cannot_store_register
;
819 /* I386 has 8 xmm regs. */
820 num_xmm_registers
= 8;
823 /* This is initialized assuming an amd64 target.
824 x86_arch_setup will correct it for i386 or amd64 targets. */
826 struct linux_target_ops the_low_target
=
842 x86_stopped_by_watchpoint
,
843 x86_stopped_data_address
,
844 /* collect_ptrace_register/supply_ptrace_register are not needed in the
845 native i386 case (no registers smaller than an xfer unit), and are not
846 used in the biarch case (HAVE_LINUX_USRREGS is not defined). */
849 /* need to fix up i386 siginfo if host is amd64 */
851 x86_linux_new_process
,
852 x86_linux_new_thread
,
853 x86_linux_prepare_to_resume