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);
138 int (*cannot_fetch_register
) (int);
140 /* Returns 0 if we can store the register, 1 if we can not
141 store the register, and 2 if failure to store the register
143 int (*cannot_store_register
) (int);
145 /* Hook to fetch a register in some non-standard way. Used for
146 example by backends that have read-only registers with hardcoded
147 values (e.g., IA64's gr0/fr0/fr1). Returns true if register
148 REGNO was supplied, false if not, and we should fallback to the
149 standard ptrace methods. */
150 int (*fetch_register
) (struct regcache
*regcache
, int regno
);
152 CORE_ADDR (*get_pc
) (struct regcache
*regcache
);
153 void (*set_pc
) (struct regcache
*regcache
, CORE_ADDR newpc
);
155 /* See target.h for details. */
156 int (*breakpoint_kind_from_pc
) (CORE_ADDR
*pcptr
);
158 /* See target.h for details. */
159 const gdb_byte
*(*sw_breakpoint_from_kind
) (int kind
, int *size
);
161 /* Find the next possible PCs after the current instruction executes. */
162 std::vector
<CORE_ADDR
> (*get_next_pcs
) (struct regcache
*regcache
);
164 int decr_pc_after_break
;
165 int (*breakpoint_at
) (CORE_ADDR pc
);
167 /* Breakpoint and watchpoint related functions. See target.h for
169 int (*supports_z_point_type
) (char z_type
);
170 int (*insert_point
) (enum raw_bkpt_type type
, CORE_ADDR addr
,
171 int size
, struct raw_breakpoint
*bp
);
172 int (*remove_point
) (enum raw_bkpt_type type
, CORE_ADDR addr
,
173 int size
, struct raw_breakpoint
*bp
);
175 int (*stopped_by_watchpoint
) (void);
176 CORE_ADDR (*stopped_data_address
) (void);
178 /* Hooks to reformat register data for PEEKUSR/POKEUSR (in particular
179 for registers smaller than an xfer unit). */
180 void (*collect_ptrace_register
) (struct regcache
*regcache
,
181 int regno
, char *buf
);
182 void (*supply_ptrace_register
) (struct regcache
*regcache
,
183 int regno
, const char *buf
);
185 /* Hook to convert from target format to ptrace format and back.
186 Returns true if any conversion was done; false otherwise.
187 If DIRECTION is 1, then copy from INF to NATIVE.
188 If DIRECTION is 0, copy from NATIVE to INF. */
189 int (*siginfo_fixup
) (siginfo_t
*native
, gdb_byte
*inf
, int direction
);
191 /* Hook to call when a new process is created or attached to.
192 If extra per-process architecture-specific data is needed,
194 struct arch_process_info
* (*new_process
) (void);
196 /* Hook to call when a process is being deleted. If extra per-process
197 architecture-specific data is needed, delete it here. */
198 void (*delete_process
) (struct arch_process_info
*info
);
200 /* Hook to call when a new thread is detected.
201 If extra per-thread architecture-specific data is needed,
203 void (*new_thread
) (struct lwp_info
*);
205 /* Hook to call when a thread is being deleted. If extra per-thread
206 architecture-specific data is needed, delete it here. */
207 void (*delete_thread
) (struct arch_lwp_info
*);
209 /* Hook to call, if any, when a new fork is attached. */
210 void (*new_fork
) (struct process_info
*parent
, struct process_info
*child
);
212 /* Hook to call prior to resuming a thread. */
213 void (*prepare_to_resume
) (struct lwp_info
*);
215 /* Hook to support target specific qSupported. */
216 void (*process_qsupported
) (char **, int count
);
218 /* Returns true if the low target supports tracepoints. */
219 int (*supports_tracepoints
) (void);
221 /* Fill ADDRP with the thread area address of LWPID. Returns 0 on
222 success, -1 on failure. */
223 int (*get_thread_area
) (int lwpid
, CORE_ADDR
*addrp
);
225 /* Install a fast tracepoint jump pad. See target.h for
227 int (*install_fast_tracepoint_jump_pad
) (CORE_ADDR tpoint
, CORE_ADDR tpaddr
,
231 CORE_ADDR
*jump_entry
,
232 CORE_ADDR
*trampoline
,
233 ULONGEST
*trampoline_size
,
234 unsigned char *jjump_pad_insn
,
235 ULONGEST
*jjump_pad_insn_size
,
236 CORE_ADDR
*adjusted_insn_addr
,
237 CORE_ADDR
*adjusted_insn_addr_end
,
240 /* Return the bytecode operations vector for the current inferior.
241 Returns NULL if bytecode compilation is not supported. */
242 struct emit_ops
*(*emit_ops
) (void);
244 /* Return the minimum length of an instruction that can be safely overwritten
245 for use as a fast tracepoint. */
246 int (*get_min_fast_tracepoint_insn_len
) (void);
248 /* Returns true if the low target supports range stepping. */
249 int (*supports_range_stepping
) (void);
252 int (*breakpoint_kind_from_current_state
) (CORE_ADDR
*pcptr
);
255 int (*supports_hardware_single_step
) (void);
257 /* Fill *SYSNO with the syscall nr trapped. Only to be called when
258 inferior is stopped due to SYSCALL_SIGTRAP. */
259 void (*get_syscall_trapinfo
) (struct regcache
*regcache
, int *sysno
);
262 int (*get_ipa_tdesc_idx
) (void);
265 extern struct linux_target_ops the_low_target
;
267 /* Target ops definitions for a Linux target. */
269 class linux_process_target
: public process_target
273 int create_inferior (const char *program
,
274 const std::vector
<char *> &program_args
) override
;
276 void post_create_inferior () override
;
278 int attach (unsigned long pid
) override
;
280 int kill (process_info
*proc
) override
;
282 int detach (process_info
*proc
) override
;
284 void mourn (process_info
*proc
) override
;
286 void join (int pid
) override
;
288 bool thread_alive (ptid_t pid
) override
;
290 void resume (thread_resume
*resume_info
, size_t n
) override
;
292 ptid_t
wait (ptid_t ptid
, target_waitstatus
*status
,
293 int options
) override
;
295 void fetch_registers (regcache
*regcache
, int regno
) override
;
297 void store_registers (regcache
*regcache
, int regno
) override
;
299 int prepare_to_access_memory () override
;
301 void done_accessing_memory () override
;
303 int read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
,
306 int write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
,
309 void look_up_symbols () override
;
311 void request_interrupt () override
;
313 bool supports_read_auxv () override
;
315 int read_auxv (CORE_ADDR offset
, unsigned char *myaddr
,
316 unsigned int len
) override
;
318 bool supports_z_point_type (char z_type
) override
;
321 #define get_thread_lwp(thr) ((struct lwp_info *) (thread_target_data (thr)))
322 #define get_lwp_thread(lwp) ((lwp)->thread)
324 /* This struct is recorded in the target_data field of struct thread_info.
326 On linux ``all_threads'' is keyed by the LWP ID, which we use as the
327 GDB protocol representation of the thread ID. Threads also have
328 a "process ID" (poorly named) which is (presently) the same as the
331 There is also ``all_processes'' is keyed by the "overall process ID",
332 which GNU/Linux calls tgid, "thread group ID". */
336 /* Backlink to the parent object. */
337 struct thread_info
*thread
;
339 /* If this flag is set, the next SIGSTOP will be ignored (the
340 process will be immediately resumed). This means that either we
341 sent the SIGSTOP to it ourselves and got some other pending event
342 (so the SIGSTOP is still pending), or that we stopped the
343 inferior implicitly via PTRACE_ATTACH and have not waited for it
347 /* When this is true, we shall not try to resume this thread, even
348 if last_resume_kind isn't resume_stop. */
351 /* If this flag is set, the lwp is known to be stopped right now (stop
352 event already received in a wait()). */
355 /* Signal whether we are in a SYSCALL_ENTRY or
356 in a SYSCALL_RETURN event.
358 - TARGET_WAITKIND_SYSCALL_ENTRY
359 - TARGET_WAITKIND_SYSCALL_RETURN */
360 enum target_waitkind syscall_state
;
362 /* When stopped is set, the last wait status recorded for this lwp. */
365 /* If WAITSTATUS->KIND != TARGET_WAITKIND_IGNORE, the waitstatus for
366 this LWP's last event, to pass to GDB without any further
367 processing. This is used to store extended ptrace event
368 information or exit status until it can be reported to GDB. */
369 struct target_waitstatus waitstatus
;
371 /* A pointer to the fork child/parent relative. Valid only while
372 the parent fork event is not reported to higher layers. Used to
373 avoid wildcard vCont actions resuming a fork child before GDB is
374 notified about the parent's fork event. */
375 struct lwp_info
*fork_relative
;
377 /* When stopped is set, this is where the lwp last stopped, with
378 decr_pc_after_break already accounted for. If the LWP is
379 running, this is the address at which the lwp was resumed. */
382 /* If this flag is set, STATUS_PENDING is a waitstatus that has not yet
384 int status_pending_p
;
387 /* The reason the LWP last stopped, if we need to track it
388 (breakpoint, watchpoint, etc.) */
389 enum target_stop_reason stop_reason
;
391 /* On architectures where it is possible to know the data address of
392 a triggered watchpoint, STOPPED_DATA_ADDRESS is non-zero, and
393 contains such data address. Only valid if STOPPED_BY_WATCHPOINT
395 CORE_ADDR stopped_data_address
;
397 /* If this is non-zero, it is a breakpoint to be reinserted at our next
398 stop (SIGTRAP stops only). */
399 CORE_ADDR bp_reinsert
;
401 /* If this flag is set, the last continue operation at the ptrace
402 level on this process was a single-step. */
405 /* Range to single step within. This is a copy of the step range
406 passed along the last resume request. See 'struct
408 CORE_ADDR step_range_start
; /* Inclusive */
409 CORE_ADDR step_range_end
; /* Exclusive */
411 /* If this flag is set, we need to set the event request flags the
412 next time we see this LWP stop. */
413 int must_set_ptrace_flags
;
415 /* If this is non-zero, it points to a chain of signals which need to
416 be delivered to this process. */
417 struct pending_signals
*pending_signals
;
419 /* A link used when resuming. It is initialized from the resume request,
420 and then processed and cleared in linux_resume_one_lwp. */
421 struct thread_resume
*resume
;
423 /* Information bout this lwp's fast tracepoint collection status (is it
424 currently stopped in the jump pad, and if so, before or at/after the
425 relocated instruction). Normally, we won't care about this, but we will
426 if a signal arrives to this lwp while it is collecting. */
427 fast_tpoint_collect_result collecting_fast_tracepoint
;
429 /* If this is non-zero, it points to a chain of signals which need
430 to be reported to GDB. These were deferred because the thread
431 was doing a fast tracepoint collect when they arrived. */
432 struct pending_signals
*pending_signals_to_report
;
434 /* When collecting_fast_tracepoint is first found to be 1, we insert
435 a exit-jump-pad-quickly breakpoint. This is it. */
436 struct breakpoint
*exit_jump_pad_bkpt
;
440 /* The thread handle, used for e.g. TLS access. Only valid if
441 THREAD_KNOWN is set. */
444 /* The pthread_t handle. */
445 thread_t thread_handle
;
448 /* Arch-specific additions. */
449 struct arch_lwp_info
*arch_private
;
452 int linux_pid_exe_is_elf_64_file (int pid
, unsigned int *machine
);
454 /* Attach to PTID. Returns 0 on success, non-zero otherwise (an
456 int linux_attach_lwp (ptid_t ptid
);
458 struct lwp_info
*find_lwp_pid (ptid_t ptid
);
459 /* For linux_stop_lwp see nat/linux-nat.h. */
461 #ifdef HAVE_LINUX_REGSETS
462 void initialize_regsets_info (struct regsets_info
*regsets_info
);
465 void initialize_low_arch (void);
467 void linux_set_pc_32bit (struct regcache
*regcache
, CORE_ADDR pc
);
468 CORE_ADDR
linux_get_pc_32bit (struct regcache
*regcache
);
470 void linux_set_pc_64bit (struct regcache
*regcache
, CORE_ADDR pc
);
471 CORE_ADDR
linux_get_pc_64bit (struct regcache
*regcache
);
473 /* From thread-db.c */
474 int thread_db_init (void);
475 void thread_db_detach (struct process_info
*);
476 void thread_db_mourn (struct process_info
*);
477 int thread_db_handle_monitor_command (char *);
478 int thread_db_get_tls_address (struct thread_info
*thread
, CORE_ADDR offset
,
479 CORE_ADDR load_module
, CORE_ADDR
*address
);
480 int thread_db_look_up_one_symbol (const char *name
, CORE_ADDR
*addrp
);
482 /* Called from linux-low.c when a clone event is detected. Upon entry,
483 both the clone and the parent should be stopped. This function does
484 whatever is required have the clone under thread_db's control. */
486 void thread_db_notice_clone (struct thread_info
*parent_thr
, ptid_t child_ptid
);
488 bool thread_db_thread_handle (ptid_t ptid
, gdb_byte
**handle
, int *handle_len
);
490 extern int have_ptrace_getregset
;
492 /* Search for the value with type MATCH in the auxv vector with
493 entries of length WORDSIZE bytes. If found, store the value in
494 *VALP and return 1. If not found or if there is an error, return
497 int linux_get_auxv (int wordsize
, CORE_ADDR match
,
500 /* Fetch the AT_HWCAP entry from the auxv vector, where entries are length
501 WORDSIZE. If no entry was found, return zero. */
503 CORE_ADDR
linux_get_hwcap (int wordsize
);
505 /* Fetch the AT_HWCAP2 entry from the auxv vector, where entries are length
506 WORDSIZE. If no entry was found, return zero. */
508 CORE_ADDR
linux_get_hwcap2 (int wordsize
);
510 #endif /* GDBSERVER_LINUX_LOW_H */