1 /* Internal interfaces for the GNU/Linux specific target code for gdbserver.
2 Copyright (C) 2002-2016 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 #include "nat/linux-nat.h"
20 #include "nat/gdb_thread_db.h"
23 #include "gdbthread.h"
24 #include "gdb_proc_service.h"
26 /* Included for ptrace type definitions. */
27 #include "nat/linux-ptrace.h"
28 #include "target/waitstatus.h" /* For enum target_stop_reason. */
30 #define PTRACE_XFER_TYPE long
32 #ifdef HAVE_LINUX_REGSETS
33 typedef void (*regset_fill_func) (struct regcache *, void *);
34 typedef void (*regset_store_func) (struct regcache *, const void *);
41 /* The arch's regsets array initializer must be terminated with a NULL
44 { 0, 0, 0, -1, (enum regset_type) -1, NULL, NULL }
48 int get_request, set_request;
49 /* If NT_TYPE isn't 0, it will be passed to ptrace as the 3rd
50 argument and the 4th argument should be "const struct iovec *". */
53 enum regset_type type;
54 regset_fill_func fill_function;
55 regset_store_func store_function;
58 /* Aggregation of all the supported regsets of a given
63 /* The regsets array. */
64 struct regset_info *regsets;
66 /* The number of regsets in the REGSETS array. */
69 /* If we get EIO on a regset, do not try it again. Note the set of
70 supported regsets may depend on processor mode on biarch
71 machines. This is a (lazily allocated) array holding one boolean
72 byte (0/1) per regset, with each element corresponding to the
73 regset in the REGSETS array above at the same offset. */
74 char *disabled_regsets;
79 /* Mapping between the general-purpose registers in `struct user'
80 format and GDB's register array layout. */
84 /* The number of registers accessible. */
87 /* The registers map. */
91 /* All info needed to access an architecture/mode's registers. */
95 /* Regset support bitmap: 1 for registers that are transferred as a part
96 of a regset, 0 for ones that need to be handled individually. This
97 can be NULL if all registers are transferred with regsets or regsets
99 unsigned char *regset_bitmap;
101 /* Info used when accessing registers with PTRACE_PEEKUSER /
102 PTRACE_POKEUSER. This can be NULL if all registers are
103 transferred with regsets .*/
104 struct usrregs_info *usrregs;
106 #ifdef HAVE_LINUX_REGSETS
107 /* Info used when accessing registers with regsets. */
108 struct regsets_info *regsets_info;
112 struct process_info_private
114 /* Arch-specific additions. */
115 struct arch_process_info *arch_private;
117 /* libthread_db-specific additions. Not NULL if this process has loaded
118 thread_db, and it is active. */
119 struct thread_db *thread_db;
121 /* &_r_debug. 0 if not yet determined. -1 if no PT_DYNAMIC in Phdrs. */
127 struct linux_target_ops
129 /* Architecture-specific setup. */
130 void (*arch_setup) (void);
132 const struct regs_info *(*regs_info) (void);
133 int (*cannot_fetch_register) (int);
135 /* Returns 0 if we can store the register, 1 if we can not
136 store the register, and 2 if failure to store the register
138 int (*cannot_store_register) (int);
140 /* Hook to fetch a register in some non-standard way. Used for
141 example by backends that have read-only registers with hardcoded
142 values (e.g., IA64's gr0/fr0/fr1). Returns true if register
143 REGNO was supplied, false if not, and we should fallback to the
144 standard ptrace methods. */
145 int (*fetch_register) (struct regcache *regcache, int regno);
147 CORE_ADDR (*get_pc) (struct regcache *regcache);
148 void (*set_pc) (struct regcache *regcache, CORE_ADDR newpc);
150 /* See target.h for details. */
151 int (*breakpoint_kind_from_pc) (CORE_ADDR *pcptr);
153 /* See target.h for details. */
154 const gdb_byte *(*sw_breakpoint_from_kind) (int kind, int *size);
156 /* Find the next possible PCs after the current instruction executes. */
157 VEC (CORE_ADDR) *(*get_next_pcs) (CORE_ADDR pc, struct regcache *regcache);
159 int decr_pc_after_break;
160 int (*breakpoint_at) (CORE_ADDR pc);
162 /* Breakpoint and watchpoint related functions. See target.h for
164 int (*supports_z_point_type) (char z_type);
165 int (*insert_point) (enum raw_bkpt_type type, CORE_ADDR addr,
166 int size, struct raw_breakpoint *bp);
167 int (*remove_point) (enum raw_bkpt_type type, CORE_ADDR addr,
168 int size, struct raw_breakpoint *bp);
170 int (*stopped_by_watchpoint) (void);
171 CORE_ADDR (*stopped_data_address) (void);
173 /* Hooks to reformat register data for PEEKUSR/POKEUSR (in particular
174 for registers smaller than an xfer unit). */
175 void (*collect_ptrace_register) (struct regcache *regcache,
176 int regno, char *buf);
177 void (*supply_ptrace_register) (struct regcache *regcache,
178 int regno, const char *buf);
180 /* Hook to convert from target format to ptrace format and back.
181 Returns true if any conversion was done; false otherwise.
182 If DIRECTION is 1, then copy from INF to NATIVE.
183 If DIRECTION is 0, copy from NATIVE to INF. */
184 int (*siginfo_fixup) (siginfo_t *native, void *inf, int direction);
186 /* Hook to call when a new process is created or attached to.
187 If extra per-process architecture-specific data is needed,
189 struct arch_process_info * (*new_process) (void);
191 /* Hook to call when a new thread is detected.
192 If extra per-thread architecture-specific data is needed,
194 void (*new_thread) (struct lwp_info *);
196 /* Hook to call, if any, when a new fork is attached. */
197 void (*new_fork) (struct process_info *parent, struct process_info *child);
199 /* Hook to call prior to resuming a thread. */
200 void (*prepare_to_resume) (struct lwp_info *);
202 /* Hook to support target specific qSupported. */
203 void (*process_qsupported) (char **, int count);
205 /* Returns true if the low target supports tracepoints. */
206 int (*supports_tracepoints) (void);
208 /* Fill ADDRP with the thread area address of LWPID. Returns 0 on
209 success, -1 on failure. */
210 int (*get_thread_area) (int lwpid, CORE_ADDR *addrp);
212 /* Install a fast tracepoint jump pad. See target.h for
214 int (*install_fast_tracepoint_jump_pad) (CORE_ADDR tpoint, CORE_ADDR tpaddr,
218 CORE_ADDR *jump_entry,
219 CORE_ADDR *trampoline,
220 ULONGEST *trampoline_size,
221 unsigned char *jjump_pad_insn,
222 ULONGEST *jjump_pad_insn_size,
223 CORE_ADDR *adjusted_insn_addr,
224 CORE_ADDR *adjusted_insn_addr_end,
227 /* Return the bytecode operations vector for the current inferior.
228 Returns NULL if bytecode compilation is not supported. */
229 struct emit_ops *(*emit_ops) (void);
231 /* Return the minimum length of an instruction that can be safely overwritten
232 for use as a fast tracepoint. */
233 int (*get_min_fast_tracepoint_insn_len) (void);
235 /* Returns true if the low target supports range stepping. */
236 int (*supports_range_stepping) (void);
239 int (*breakpoint_kind_from_current_state) (CORE_ADDR *pcptr);
242 int (*supports_hardware_single_step) (void);
244 /* Fill *SYSNO with the syscall nr trapped. Fill *SYSRET with the
245 return code. Only to be called when inferior is stopped
246 due to SYSCALL_SIGTRAP. */
247 void (*get_syscall_trapinfo) (struct regcache *regcache,
248 int *sysno, int *sysret);
251 extern struct linux_target_ops the_low_target;
253 #define get_thread_lwp(thr) ((struct lwp_info *) (inferior_target_data (thr)))
254 #define get_lwp_thread(lwp) ((lwp)->thread)
256 /* This struct is recorded in the target_data field of struct thread_info.
258 On linux ``all_threads'' is keyed by the LWP ID, which we use as the
259 GDB protocol representation of the thread ID. Threads also have
260 a "process ID" (poorly named) which is (presently) the same as the
263 There is also ``all_processes'' is keyed by the "overall process ID",
264 which GNU/Linux calls tgid, "thread group ID". */
268 /* Backlink to the parent object. */
269 struct thread_info *thread;
271 /* If this flag is set, the next SIGSTOP will be ignored (the
272 process will be immediately resumed). This means that either we
273 sent the SIGSTOP to it ourselves and got some other pending event
274 (so the SIGSTOP is still pending), or that we stopped the
275 inferior implicitly via PTRACE_ATTACH and have not waited for it
279 /* When this is true, we shall not try to resume this thread, even
280 if last_resume_kind isn't resume_stop. */
283 /* If this flag is set, the lwp is known to be stopped right now (stop
284 event already received in a wait()). */
287 /* Signal whether we are in a SYSCALL_ENTRY or
288 in a SYSCALL_RETURN event.
290 - TARGET_WAITKIND_SYSCALL_ENTRY
291 - TARGET_WAITKIND_SYSCALL_RETURN */
292 enum target_waitkind syscall_state;
294 /* When stopped is set, the last wait status recorded for this lwp. */
297 /* If WAITSTATUS->KIND != TARGET_WAITKIND_IGNORE, the waitstatus for
298 this LWP's last event, to pass to GDB without any further
299 processing. This is used to store extended ptrace event
300 information or exit status until it can be reported to GDB. */
301 struct target_waitstatus waitstatus;
303 /* When stopped is set, this is where the lwp last stopped, with
304 decr_pc_after_break already accounted for. If the LWP is
305 running, this is the address at which the lwp was resumed. */
308 /* If this flag is set, STATUS_PENDING is a waitstatus that has not yet
310 int status_pending_p;
313 /* The reason the LWP last stopped, if we need to track it
314 (breakpoint, watchpoint, etc.) */
315 enum target_stop_reason stop_reason;
317 /* On architectures where it is possible to know the data address of
318 a triggered watchpoint, STOPPED_DATA_ADDRESS is non-zero, and
319 contains such data address. Only valid if STOPPED_BY_WATCHPOINT
321 CORE_ADDR stopped_data_address;
323 /* If this is non-zero, it is a breakpoint to be reinserted at our next
324 stop (SIGTRAP stops only). */
325 CORE_ADDR bp_reinsert;
327 /* If this flag is set, the last continue operation at the ptrace
328 level on this process was a single-step. */
331 /* Range to single step within. This is a copy of the step range
332 passed along the last resume request. See 'struct
334 CORE_ADDR step_range_start; /* Inclusive */
335 CORE_ADDR step_range_end; /* Exclusive */
337 /* If this flag is set, we need to set the event request flags the
338 next time we see this LWP stop. */
339 int must_set_ptrace_flags;
341 /* If this is non-zero, it points to a chain of signals which need to
342 be delivered to this process. */
343 struct pending_signals *pending_signals;
345 /* A link used when resuming. It is initialized from the resume request,
346 and then processed and cleared in linux_resume_one_lwp. */
347 struct thread_resume *resume;
349 /* True if it is known that this lwp is presently collecting a fast
350 tracepoint (it is in the jump pad or in some code that will
351 return to the jump pad. Normally, we won't care about this, but
352 we will if a signal arrives to this lwp while it is
354 int collecting_fast_tracepoint;
356 /* If this is non-zero, it points to a chain of signals which need
357 to be reported to GDB. These were deferred because the thread
358 was doing a fast tracepoint collect when they arrived. */
359 struct pending_signals *pending_signals_to_report;
361 /* When collecting_fast_tracepoint is first found to be 1, we insert
362 a exit-jump-pad-quickly breakpoint. This is it. */
363 struct breakpoint *exit_jump_pad_bkpt;
365 /* True if the LWP was seen stop at an internal breakpoint and needs
366 stepping over later when it is resumed. */
371 /* The thread handle, used for e.g. TLS access. Only valid if
372 THREAD_KNOWN is set. */
376 /* Arch-specific additions. */
377 struct arch_lwp_info *arch_private;
380 int linux_pid_exe_is_elf_64_file (int pid, unsigned int *machine);
382 /* Attach to PTID. Returns 0 on success, non-zero otherwise (an
384 int linux_attach_lwp (ptid_t ptid);
386 struct lwp_info *find_lwp_pid (ptid_t ptid);
387 /* For linux_stop_lwp see nat/linux-nat.h. */
389 #ifdef HAVE_LINUX_REGSETS
390 void initialize_regsets_info (struct regsets_info *regsets_info);
393 void initialize_low_arch (void);
395 /* From thread-db.c */
396 int thread_db_init (void);
397 void thread_db_detach (struct process_info *);
398 void thread_db_mourn (struct process_info *);
399 int thread_db_handle_monitor_command (char *);
400 int thread_db_get_tls_address (struct thread_info *thread, CORE_ADDR offset,
401 CORE_ADDR load_module, CORE_ADDR *address);
402 int thread_db_look_up_one_symbol (const char *name, CORE_ADDR *addrp);
404 extern int have_ptrace_getregset;