1 /* Internal interfaces for the GNU/Linux specific target code for gdbserver.
2 Copyright (C) 2002-2020 Free Software Foundation, Inc.
4 This file is part of GDB.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>. */
19 #ifndef GDBSERVER_LINUX_LOW_H
20 #define GDBSERVER_LINUX_LOW_H
22 #include "nat/linux-nat.h"
23 #include "nat/gdb_thread_db.h"
26 #include "gdbthread.h"
27 #include "gdb_proc_service.h"
29 /* Included for ptrace type definitions. */
30 #include "nat/linux-ptrace.h"
31 #include "target/waitstatus.h" /* For enum target_stop_reason. */
32 #include "tracepoint.h"
34 #define PTRACE_XFER_TYPE long
36 #ifdef HAVE_LINUX_REGSETS
37 typedef void (*regset_fill_func
) (struct regcache
*, void *);
38 typedef void (*regset_store_func
) (struct regcache
*, const void *);
43 OPTIONAL_REGS
, /* Do not error if the regset cannot be accessed. */
46 /* The arch's regsets array initializer must be terminated with a NULL
49 { 0, 0, 0, -1, (enum regset_type) -1, NULL, NULL }
53 int get_request
, set_request
;
54 /* If NT_TYPE isn't 0, it will be passed to ptrace as the 3rd
55 argument and the 4th argument should be "const struct iovec *". */
58 enum regset_type type
;
59 regset_fill_func fill_function
;
60 regset_store_func store_function
;
63 /* Aggregation of all the supported regsets of a given
68 /* The regsets array. */
69 struct regset_info
*regsets
;
71 /* The number of regsets in the REGSETS array. */
74 /* If we get EIO on a regset, do not try it again. Note the set of
75 supported regsets may depend on processor mode on biarch
76 machines. This is a (lazily allocated) array holding one boolean
77 byte (0/1) per regset, with each element corresponding to the
78 regset in the REGSETS array above at the same offset. */
79 char *disabled_regsets
;
84 /* Mapping between the general-purpose registers in `struct user'
85 format and GDB's register array layout. */
89 /* The number of registers accessible. */
92 /* The registers map. */
96 /* All info needed to access an architecture/mode's registers. */
100 /* Regset support bitmap: 1 for registers that are transferred as a part
101 of a regset, 0 for ones that need to be handled individually. This
102 can be NULL if all registers are transferred with regsets or regsets
103 are not supported. */
104 unsigned char *regset_bitmap
;
106 /* Info used when accessing registers with PTRACE_PEEKUSER /
107 PTRACE_POKEUSER. This can be NULL if all registers are
108 transferred with regsets .*/
109 struct usrregs_info
*usrregs
;
111 #ifdef HAVE_LINUX_REGSETS
112 /* Info used when accessing registers with regsets. */
113 struct regsets_info
*regsets_info
;
117 struct process_info_private
119 /* Arch-specific additions. */
120 struct arch_process_info
*arch_private
;
122 /* libthread_db-specific additions. Not NULL if this process has loaded
123 thread_db, and it is active. */
124 struct thread_db
*thread_db
;
126 /* &_r_debug. 0 if not yet determined. -1 if no PT_DYNAMIC in Phdrs. */
132 struct linux_target_ops
134 /* Architecture-specific setup. */
135 void (*arch_setup
) (void);
137 const struct regs_info
*(*regs_info
) (void);
139 /* Return 0 if we can fetch/store the register, 1 if we cannot
140 fetch/store the register. */
141 int (*cannot_fetch_register
) (int);
142 int (*cannot_store_register
) (int);
144 /* Hook to fetch a register in some non-standard way. Used for
145 example by backends that have read-only registers with hardcoded
146 values (e.g., IA64's gr0/fr0/fr1). Returns true if register
147 REGNO was supplied, false if not, and we should fallback to the
148 standard ptrace methods. */
149 int (*fetch_register
) (struct regcache
*regcache
, int regno
);
151 CORE_ADDR (*get_pc
) (struct regcache
*regcache
);
152 void (*set_pc
) (struct regcache
*regcache
, CORE_ADDR newpc
);
154 /* See target.h for details. */
155 int (*breakpoint_kind_from_pc
) (CORE_ADDR
*pcptr
);
157 /* See target.h for details. */
158 const gdb_byte
*(*sw_breakpoint_from_kind
) (int kind
, int *size
);
160 /* Find the next possible PCs after the current instruction executes. */
161 std::vector
<CORE_ADDR
> (*get_next_pcs
) (struct regcache
*regcache
);
163 int decr_pc_after_break
;
164 int (*breakpoint_at
) (CORE_ADDR pc
);
166 /* Breakpoint and watchpoint related functions. See target.h for
168 int (*supports_z_point_type
) (char z_type
);
169 int (*insert_point
) (enum raw_bkpt_type type
, CORE_ADDR addr
,
170 int size
, struct raw_breakpoint
*bp
);
171 int (*remove_point
) (enum raw_bkpt_type type
, CORE_ADDR addr
,
172 int size
, struct raw_breakpoint
*bp
);
174 int (*stopped_by_watchpoint
) (void);
175 CORE_ADDR (*stopped_data_address
) (void);
177 /* Hooks to reformat register data for PEEKUSR/POKEUSR (in particular
178 for registers smaller than an xfer unit). */
179 void (*collect_ptrace_register
) (struct regcache
*regcache
,
180 int regno
, char *buf
);
181 void (*supply_ptrace_register
) (struct regcache
*regcache
,
182 int regno
, const char *buf
);
184 /* Hook to convert from target format to ptrace format and back.
185 Returns true if any conversion was done; false otherwise.
186 If DIRECTION is 1, then copy from INF to NATIVE.
187 If DIRECTION is 0, copy from NATIVE to INF. */
188 int (*siginfo_fixup
) (siginfo_t
*native
, gdb_byte
*inf
, int direction
);
190 /* Hook to call when a new process is created or attached to.
191 If extra per-process architecture-specific data is needed,
193 struct arch_process_info
* (*new_process
) (void);
195 /* Hook to call when a process is being deleted. If extra per-process
196 architecture-specific data is needed, delete it here. */
197 void (*delete_process
) (struct arch_process_info
*info
);
199 /* Hook to call when a new thread is detected.
200 If extra per-thread architecture-specific data is needed,
202 void (*new_thread
) (struct lwp_info
*);
204 /* Hook to call when a thread is being deleted. If extra per-thread
205 architecture-specific data is needed, delete it here. */
206 void (*delete_thread
) (struct arch_lwp_info
*);
208 /* Hook to call, if any, when a new fork is attached. */
209 void (*new_fork
) (struct process_info
*parent
, struct process_info
*child
);
211 /* Hook to call prior to resuming a thread. */
212 void (*prepare_to_resume
) (struct lwp_info
*);
214 /* Hook to support target specific qSupported. */
215 void (*process_qsupported
) (char **, int count
);
217 /* Returns true if the low target supports tracepoints. */
218 int (*supports_tracepoints
) (void);
220 /* Fill ADDRP with the thread area address of LWPID. Returns 0 on
221 success, -1 on failure. */
222 int (*get_thread_area
) (int lwpid
, CORE_ADDR
*addrp
);
224 /* Install a fast tracepoint jump pad. See target.h for
226 int (*install_fast_tracepoint_jump_pad
) (CORE_ADDR tpoint
, CORE_ADDR tpaddr
,
230 CORE_ADDR
*jump_entry
,
231 CORE_ADDR
*trampoline
,
232 ULONGEST
*trampoline_size
,
233 unsigned char *jjump_pad_insn
,
234 ULONGEST
*jjump_pad_insn_size
,
235 CORE_ADDR
*adjusted_insn_addr
,
236 CORE_ADDR
*adjusted_insn_addr_end
,
239 /* Return the bytecode operations vector for the current inferior.
240 Returns NULL if bytecode compilation is not supported. */
241 struct emit_ops
*(*emit_ops
) (void);
243 /* Return the minimum length of an instruction that can be safely overwritten
244 for use as a fast tracepoint. */
245 int (*get_min_fast_tracepoint_insn_len
) (void);
247 /* Returns true if the low target supports range stepping. */
248 int (*supports_range_stepping
) (void);
251 int (*breakpoint_kind_from_current_state
) (CORE_ADDR
*pcptr
);
254 int (*supports_hardware_single_step
) (void);
256 /* Fill *SYSNO with the syscall nr trapped. Only to be called when
257 inferior is stopped due to SYSCALL_SIGTRAP. */
258 void (*get_syscall_trapinfo
) (struct regcache
*regcache
, int *sysno
);
261 int (*get_ipa_tdesc_idx
) (void);
264 extern struct linux_target_ops the_low_target
;
266 /* Target ops definitions for a Linux target. */
268 class linux_process_target
: public process_stratum_target
272 int create_inferior (const char *program
,
273 const std::vector
<char *> &program_args
) override
;
275 void post_create_inferior () override
;
277 int attach (unsigned long pid
) override
;
279 int kill (process_info
*proc
) override
;
281 int detach (process_info
*proc
) override
;
283 void mourn (process_info
*proc
) override
;
285 void join (int pid
) override
;
287 bool thread_alive (ptid_t pid
) override
;
289 void resume (thread_resume
*resume_info
, size_t n
) override
;
291 ptid_t
wait (ptid_t ptid
, target_waitstatus
*status
,
292 int options
) override
;
294 void fetch_registers (regcache
*regcache
, int regno
) override
;
296 void store_registers (regcache
*regcache
, int regno
) override
;
298 int prepare_to_access_memory () override
;
300 void done_accessing_memory () override
;
302 int read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
,
305 int write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
,
308 void look_up_symbols () override
;
310 void request_interrupt () override
;
312 bool supports_read_auxv () override
;
314 int read_auxv (CORE_ADDR offset
, unsigned char *myaddr
,
315 unsigned int len
) override
;
317 bool supports_z_point_type (char z_type
) override
;
319 int insert_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
320 int size
, raw_breakpoint
*bp
) override
;
322 int remove_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
323 int size
, raw_breakpoint
*bp
) override
;
325 bool stopped_by_sw_breakpoint () override
;
327 bool supports_stopped_by_sw_breakpoint () override
;
329 bool stopped_by_hw_breakpoint () override
;
331 bool supports_stopped_by_hw_breakpoint () override
;
333 bool supports_hardware_single_step () override
;
335 bool stopped_by_watchpoint () override
;
337 CORE_ADDR
stopped_data_address () override
;
339 bool supports_read_offsets () override
;
341 int read_offsets (CORE_ADDR
*text
, CORE_ADDR
*data
) override
;
343 bool supports_get_tls_address () override
;
345 int get_tls_address (thread_info
*thread
, CORE_ADDR offset
,
346 CORE_ADDR load_module
, CORE_ADDR
*address
) override
;
348 bool supports_qxfer_osdata () override
;
350 int qxfer_osdata (const char *annex
, unsigned char *readbuf
,
351 unsigned const char *writebuf
,
352 CORE_ADDR offset
, int len
) override
;
354 bool supports_qxfer_siginfo () override
;
356 int qxfer_siginfo (const char *annex
, unsigned char *readbuf
,
357 unsigned const char *writebuf
,
358 CORE_ADDR offset
, int len
) override
;
360 bool supports_non_stop () override
;
362 bool async (bool enable
) override
;
364 int start_non_stop (bool enable
) override
;
366 bool supports_multi_process () override
;
368 bool supports_fork_events () override
;
370 bool supports_vfork_events () override
;
372 bool supports_exec_events () override
;
374 void handle_new_gdb_connection () override
;
376 int handle_monitor_command (char *mon
) override
;
378 int core_of_thread (ptid_t ptid
) override
;
380 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
381 bool supports_read_loadmap () override
;
383 int read_loadmap (const char *annex
, CORE_ADDR offset
,
384 unsigned char *myaddr
, unsigned int len
) override
;
387 void process_qsupported (char **features
, int count
) override
;
389 bool supports_tracepoints () override
;
391 CORE_ADDR
read_pc (regcache
*regcache
) override
;
393 void write_pc (regcache
*regcache
, CORE_ADDR pc
) override
;
395 bool supports_thread_stopped () override
;
397 bool thread_stopped (thread_info
*thread
) override
;
399 void pause_all (bool freeze
) override
;
401 void unpause_all (bool unfreeze
) override
;
403 void stabilize_threads () override
;
405 bool supports_fast_tracepoints () override
;
407 int install_fast_tracepoint_jump_pad (CORE_ADDR tpoint
,
412 CORE_ADDR
*jump_entry
,
413 CORE_ADDR
*trampoline
,
414 ULONGEST
*trampoline_size
,
415 unsigned char *jjump_pad_insn
,
416 ULONGEST
*jjump_pad_insn_size
,
417 CORE_ADDR
*adjusted_insn_addr
,
418 CORE_ADDR
*adjusted_insn_addr_end
,
421 int get_min_fast_tracepoint_insn_len () override
;
423 struct emit_ops
*emit_ops () override
;
425 bool supports_disable_randomization () override
;
427 bool supports_qxfer_libraries_svr4 () override
;
429 int qxfer_libraries_svr4 (const char *annex
,
430 unsigned char *readbuf
,
431 unsigned const char *writebuf
,
432 CORE_ADDR offset
, int len
) override
;
434 bool supports_agent () override
;
436 #ifdef HAVE_LINUX_BTRACE
437 btrace_target_info
*enable_btrace (ptid_t ptid
,
438 const btrace_config
*conf
) override
;
440 int disable_btrace (btrace_target_info
*tinfo
) override
;
442 int read_btrace (btrace_target_info
*tinfo
, buffer
*buf
,
443 enum btrace_read_type type
) override
;
445 int read_btrace_conf (const btrace_target_info
*tinfo
,
446 buffer
*buf
) override
;
449 bool supports_range_stepping () override
;
451 bool supports_pid_to_exec_file () override
;
453 char *pid_to_exec_file (int pid
) override
;
455 bool supports_multifs () override
;
457 int multifs_open (int pid
, const char *filename
, int flags
,
458 mode_t mode
) override
;
460 int multifs_unlink (int pid
, const char *filename
) override
;
462 ssize_t
multifs_readlink (int pid
, const char *filename
, char *buf
,
463 size_t bufsiz
) override
;
465 int breakpoint_kind_from_pc (CORE_ADDR
*pcptr
) override
;
467 const gdb_byte
*sw_breakpoint_from_kind (int kind
, int *size
) override
;
469 int breakpoint_kind_from_current_state (CORE_ADDR
*pcptr
) override
;
471 const char *thread_name (ptid_t thread
) override
;
474 bool thread_handle (ptid_t ptid
, gdb_byte
**handle
,
475 int *handle_len
) override
;
478 bool supports_software_single_step () override
;
480 bool supports_catch_syscall () override
;
482 int get_ipa_tdesc_idx () override
;
485 #define get_thread_lwp(thr) ((struct lwp_info *) (thread_target_data (thr)))
486 #define get_lwp_thread(lwp) ((lwp)->thread)
488 /* This struct is recorded in the target_data field of struct thread_info.
490 On linux ``all_threads'' is keyed by the LWP ID, which we use as the
491 GDB protocol representation of the thread ID. Threads also have
492 a "process ID" (poorly named) which is (presently) the same as the
495 There is also ``all_processes'' is keyed by the "overall process ID",
496 which GNU/Linux calls tgid, "thread group ID". */
500 /* Backlink to the parent object. */
501 struct thread_info
*thread
;
503 /* If this flag is set, the next SIGSTOP will be ignored (the
504 process will be immediately resumed). This means that either we
505 sent the SIGSTOP to it ourselves and got some other pending event
506 (so the SIGSTOP is still pending), or that we stopped the
507 inferior implicitly via PTRACE_ATTACH and have not waited for it
511 /* When this is true, we shall not try to resume this thread, even
512 if last_resume_kind isn't resume_stop. */
515 /* If this flag is set, the lwp is known to be stopped right now (stop
516 event already received in a wait()). */
519 /* Signal whether we are in a SYSCALL_ENTRY or
520 in a SYSCALL_RETURN event.
522 - TARGET_WAITKIND_SYSCALL_ENTRY
523 - TARGET_WAITKIND_SYSCALL_RETURN */
524 enum target_waitkind syscall_state
;
526 /* When stopped is set, the last wait status recorded for this lwp. */
529 /* If WAITSTATUS->KIND != TARGET_WAITKIND_IGNORE, the waitstatus for
530 this LWP's last event, to pass to GDB without any further
531 processing. This is used to store extended ptrace event
532 information or exit status until it can be reported to GDB. */
533 struct target_waitstatus waitstatus
;
535 /* A pointer to the fork child/parent relative. Valid only while
536 the parent fork event is not reported to higher layers. Used to
537 avoid wildcard vCont actions resuming a fork child before GDB is
538 notified about the parent's fork event. */
539 struct lwp_info
*fork_relative
;
541 /* When stopped is set, this is where the lwp last stopped, with
542 decr_pc_after_break already accounted for. If the LWP is
543 running, this is the address at which the lwp was resumed. */
546 /* If this flag is set, STATUS_PENDING is a waitstatus that has not yet
548 int status_pending_p
;
551 /* The reason the LWP last stopped, if we need to track it
552 (breakpoint, watchpoint, etc.) */
553 enum target_stop_reason stop_reason
;
555 /* On architectures where it is possible to know the data address of
556 a triggered watchpoint, STOPPED_DATA_ADDRESS is non-zero, and
557 contains such data address. Only valid if STOPPED_BY_WATCHPOINT
559 CORE_ADDR stopped_data_address
;
561 /* If this is non-zero, it is a breakpoint to be reinserted at our next
562 stop (SIGTRAP stops only). */
563 CORE_ADDR bp_reinsert
;
565 /* If this flag is set, the last continue operation at the ptrace
566 level on this process was a single-step. */
569 /* Range to single step within. This is a copy of the step range
570 passed along the last resume request. See 'struct
572 CORE_ADDR step_range_start
; /* Inclusive */
573 CORE_ADDR step_range_end
; /* Exclusive */
575 /* If this flag is set, we need to set the event request flags the
576 next time we see this LWP stop. */
577 int must_set_ptrace_flags
;
579 /* If this is non-zero, it points to a chain of signals which need to
580 be delivered to this process. */
581 struct pending_signals
*pending_signals
;
583 /* A link used when resuming. It is initialized from the resume request,
584 and then processed and cleared in linux_resume_one_lwp. */
585 struct thread_resume
*resume
;
587 /* Information bout this lwp's fast tracepoint collection status (is it
588 currently stopped in the jump pad, and if so, before or at/after the
589 relocated instruction). Normally, we won't care about this, but we will
590 if a signal arrives to this lwp while it is collecting. */
591 fast_tpoint_collect_result collecting_fast_tracepoint
;
593 /* If this is non-zero, it points to a chain of signals which need
594 to be reported to GDB. These were deferred because the thread
595 was doing a fast tracepoint collect when they arrived. */
596 struct pending_signals
*pending_signals_to_report
;
598 /* When collecting_fast_tracepoint is first found to be 1, we insert
599 a exit-jump-pad-quickly breakpoint. This is it. */
600 struct breakpoint
*exit_jump_pad_bkpt
;
604 /* The thread handle, used for e.g. TLS access. Only valid if
605 THREAD_KNOWN is set. */
608 /* The pthread_t handle. */
609 thread_t thread_handle
;
612 /* Arch-specific additions. */
613 struct arch_lwp_info
*arch_private
;
616 int linux_pid_exe_is_elf_64_file (int pid
, unsigned int *machine
);
618 /* Attach to PTID. Returns 0 on success, non-zero otherwise (an
620 int linux_attach_lwp (ptid_t ptid
);
622 struct lwp_info
*find_lwp_pid (ptid_t ptid
);
623 /* For linux_stop_lwp see nat/linux-nat.h. */
625 #ifdef HAVE_LINUX_REGSETS
626 void initialize_regsets_info (struct regsets_info
*regsets_info
);
629 void initialize_low_arch (void);
631 void linux_set_pc_32bit (struct regcache
*regcache
, CORE_ADDR pc
);
632 CORE_ADDR
linux_get_pc_32bit (struct regcache
*regcache
);
634 void linux_set_pc_64bit (struct regcache
*regcache
, CORE_ADDR pc
);
635 CORE_ADDR
linux_get_pc_64bit (struct regcache
*regcache
);
637 /* From thread-db.c */
638 int thread_db_init (void);
639 void thread_db_detach (struct process_info
*);
640 void thread_db_mourn (struct process_info
*);
641 int thread_db_handle_monitor_command (char *);
642 int thread_db_get_tls_address (struct thread_info
*thread
, CORE_ADDR offset
,
643 CORE_ADDR load_module
, CORE_ADDR
*address
);
644 int thread_db_look_up_one_symbol (const char *name
, CORE_ADDR
*addrp
);
646 /* Called from linux-low.c when a clone event is detected. Upon entry,
647 both the clone and the parent should be stopped. This function does
648 whatever is required have the clone under thread_db's control. */
650 void thread_db_notice_clone (struct thread_info
*parent_thr
, ptid_t child_ptid
);
652 bool thread_db_thread_handle (ptid_t ptid
, gdb_byte
**handle
, int *handle_len
);
654 extern int have_ptrace_getregset
;
656 /* Search for the value with type MATCH in the auxv vector with
657 entries of length WORDSIZE bytes. If found, store the value in
658 *VALP and return 1. If not found or if there is an error, return
661 int linux_get_auxv (int wordsize
, CORE_ADDR match
,
664 /* Fetch the AT_HWCAP entry from the auxv vector, where entries are length
665 WORDSIZE. If no entry was found, return zero. */
667 CORE_ADDR
linux_get_hwcap (int wordsize
);
669 /* Fetch the AT_HWCAP2 entry from the auxv vector, where entries are length
670 WORDSIZE. If no entry was found, return zero. */
672 CORE_ADDR
linux_get_hwcap2 (int wordsize
);
674 #endif /* GDBSERVER_LINUX_LOW_H */