]>
Commit | Line | Data |
---|---|---|
ae7467b1 AB |
1 | /* |
2 | * gdbstub user-mode helper routines. | |
3 | * | |
4 | * We know for user-mode we are using TCG so we can call stuff directly. | |
5 | * | |
9455762f | 6 | * Copyright (c) 2003-2005 Fabrice Bellard |
ae7467b1 AB |
7 | * Copyright (c) 2022 Linaro Ltd |
8 | * | |
9455762f | 9 | * SPDX-License-Identifier: LGPL-2.0+ |
ae7467b1 AB |
10 | */ |
11 | ||
12 | #include "qemu/osdep.h" | |
d96bf49b AB |
13 | #include "qemu/cutils.h" |
14 | #include "qemu/sockets.h" | |
15 | #include "exec/hwaddr.h" | |
16 | #include "exec/tb-flush.h" | |
ae7467b1 | 17 | #include "exec/gdbstub.h" |
d96bf49b | 18 | #include "gdbstub/user.h" |
ae7467b1 | 19 | #include "hw/core/cpu.h" |
d96bf49b | 20 | #include "trace.h" |
ae7467b1 AB |
21 | #include "internals.h" |
22 | ||
d96bf49b AB |
23 | /* User-mode specific state */ |
24 | typedef struct { | |
25 | int fd; | |
26 | char *socket_path; | |
27 | int running_state; | |
28 | } GDBUserState; | |
29 | ||
30 | static GDBUserState gdbserver_user_state; | |
31 | ||
32 | int gdb_get_char(void) | |
33 | { | |
34 | uint8_t ch; | |
35 | int ret; | |
36 | ||
37 | for (;;) { | |
38 | ret = recv(gdbserver_user_state.fd, &ch, 1, 0); | |
39 | if (ret < 0) { | |
40 | if (errno == ECONNRESET) { | |
41 | gdbserver_user_state.fd = -1; | |
42 | } | |
43 | if (errno != EINTR) { | |
44 | return -1; | |
45 | } | |
46 | } else if (ret == 0) { | |
47 | close(gdbserver_user_state.fd); | |
48 | gdbserver_user_state.fd = -1; | |
49 | return -1; | |
50 | } else { | |
51 | break; | |
52 | } | |
53 | } | |
54 | return ch; | |
55 | } | |
56 | ||
57 | void gdb_put_buffer(const uint8_t *buf, int len) | |
58 | { | |
59 | int ret; | |
60 | ||
61 | while (len > 0) { | |
62 | ret = send(gdbserver_user_state.fd, buf, len, 0); | |
63 | if (ret < 0) { | |
64 | if (errno != EINTR) { | |
65 | return; | |
66 | } | |
67 | } else { | |
68 | buf += ret; | |
69 | len -= ret; | |
70 | } | |
71 | } | |
72 | } | |
73 | ||
74 | /* Tell the remote gdb that the process has exited. */ | |
75 | void gdb_exit(int code) | |
76 | { | |
77 | char buf[4]; | |
78 | ||
79 | if (!gdbserver_state.init) { | |
80 | return; | |
81 | } | |
82 | if (gdbserver_user_state.socket_path) { | |
83 | unlink(gdbserver_user_state.socket_path); | |
84 | } | |
85 | if (gdbserver_user_state.fd < 0) { | |
86 | return; | |
87 | } | |
88 | ||
89 | trace_gdbstub_op_exiting((uint8_t)code); | |
90 | ||
91 | snprintf(buf, sizeof(buf), "W%02x", (uint8_t)code); | |
92 | gdb_put_packet(buf); | |
93 | } | |
94 | ||
95 | int gdb_handlesig(CPUState *cpu, int sig) | |
96 | { | |
97 | char buf[256]; | |
98 | int n; | |
99 | ||
100 | if (!gdbserver_state.init || gdbserver_user_state.fd < 0) { | |
101 | return sig; | |
102 | } | |
103 | ||
104 | /* disable single step if it was enabled */ | |
105 | cpu_single_step(cpu, 0); | |
106 | tb_flush(cpu); | |
107 | ||
108 | if (sig != 0) { | |
109 | gdb_set_stop_cpu(cpu); | |
110 | g_string_printf(gdbserver_state.str_buf, | |
111 | "T%02xthread:", gdb_target_signal_to_gdb(sig)); | |
112 | gdb_append_thread_id(cpu, gdbserver_state.str_buf); | |
113 | g_string_append_c(gdbserver_state.str_buf, ';'); | |
114 | gdb_put_strbuf(); | |
115 | } | |
116 | /* | |
117 | * gdb_put_packet() might have detected that the peer terminated the | |
118 | * connection. | |
119 | */ | |
120 | if (gdbserver_user_state.fd < 0) { | |
121 | return sig; | |
122 | } | |
123 | ||
124 | sig = 0; | |
125 | gdbserver_state.state = RS_IDLE; | |
126 | gdbserver_user_state.running_state = 0; | |
127 | while (gdbserver_user_state.running_state == 0) { | |
128 | n = read(gdbserver_user_state.fd, buf, 256); | |
129 | if (n > 0) { | |
130 | int i; | |
131 | ||
132 | for (i = 0; i < n; i++) { | |
133 | gdb_read_byte(buf[i]); | |
134 | } | |
135 | } else { | |
136 | /* | |
137 | * XXX: Connection closed. Should probably wait for another | |
138 | * connection before continuing. | |
139 | */ | |
140 | if (n == 0) { | |
141 | close(gdbserver_user_state.fd); | |
142 | } | |
143 | gdbserver_user_state.fd = -1; | |
144 | return sig; | |
145 | } | |
146 | } | |
147 | sig = gdbserver_state.signal; | |
148 | gdbserver_state.signal = 0; | |
149 | return sig; | |
150 | } | |
151 | ||
152 | /* Tell the remote gdb that the process has exited due to SIG. */ | |
153 | void gdb_signalled(CPUArchState *env, int sig) | |
154 | { | |
155 | char buf[4]; | |
156 | ||
157 | if (!gdbserver_state.init || gdbserver_user_state.fd < 0) { | |
158 | return; | |
159 | } | |
160 | ||
161 | snprintf(buf, sizeof(buf), "X%02x", gdb_target_signal_to_gdb(sig)); | |
162 | gdb_put_packet(buf); | |
163 | } | |
164 | ||
165 | static void gdb_accept_init(int fd) | |
166 | { | |
167 | gdb_init_gdbserver_state(); | |
168 | gdb_create_default_process(&gdbserver_state); | |
169 | gdbserver_state.processes[0].attached = true; | |
170 | gdbserver_state.c_cpu = gdb_first_attached_cpu(); | |
171 | gdbserver_state.g_cpu = gdbserver_state.c_cpu; | |
172 | gdbserver_user_state.fd = fd; | |
173 | gdb_has_xml = false; | |
174 | } | |
175 | ||
176 | static bool gdb_accept_socket(int gdb_fd) | |
177 | { | |
178 | int fd; | |
179 | ||
180 | for (;;) { | |
181 | fd = accept(gdb_fd, NULL, NULL); | |
182 | if (fd < 0 && errno != EINTR) { | |
183 | perror("accept socket"); | |
184 | return false; | |
185 | } else if (fd >= 0) { | |
186 | qemu_set_cloexec(fd); | |
187 | break; | |
188 | } | |
189 | } | |
190 | ||
191 | gdb_accept_init(fd); | |
192 | return true; | |
193 | } | |
194 | ||
195 | static int gdbserver_open_socket(const char *path) | |
196 | { | |
197 | struct sockaddr_un sockaddr = {}; | |
198 | int fd, ret; | |
199 | ||
200 | fd = socket(AF_UNIX, SOCK_STREAM, 0); | |
201 | if (fd < 0) { | |
202 | perror("create socket"); | |
203 | return -1; | |
204 | } | |
205 | ||
206 | sockaddr.sun_family = AF_UNIX; | |
207 | pstrcpy(sockaddr.sun_path, sizeof(sockaddr.sun_path) - 1, path); | |
208 | ret = bind(fd, (struct sockaddr *)&sockaddr, sizeof(sockaddr)); | |
209 | if (ret < 0) { | |
210 | perror("bind socket"); | |
211 | close(fd); | |
212 | return -1; | |
213 | } | |
214 | ret = listen(fd, 1); | |
215 | if (ret < 0) { | |
216 | perror("listen socket"); | |
217 | close(fd); | |
218 | return -1; | |
219 | } | |
220 | ||
221 | return fd; | |
222 | } | |
223 | ||
224 | static bool gdb_accept_tcp(int gdb_fd) | |
225 | { | |
226 | struct sockaddr_in sockaddr = {}; | |
227 | socklen_t len; | |
228 | int fd; | |
229 | ||
230 | for (;;) { | |
231 | len = sizeof(sockaddr); | |
232 | fd = accept(gdb_fd, (struct sockaddr *)&sockaddr, &len); | |
233 | if (fd < 0 && errno != EINTR) { | |
234 | perror("accept"); | |
235 | return false; | |
236 | } else if (fd >= 0) { | |
237 | qemu_set_cloexec(fd); | |
238 | break; | |
239 | } | |
240 | } | |
241 | ||
242 | /* set short latency */ | |
243 | if (socket_set_nodelay(fd)) { | |
244 | perror("setsockopt"); | |
245 | close(fd); | |
246 | return false; | |
247 | } | |
248 | ||
249 | gdb_accept_init(fd); | |
250 | return true; | |
251 | } | |
252 | ||
253 | static int gdbserver_open_port(int port) | |
254 | { | |
255 | struct sockaddr_in sockaddr; | |
256 | int fd, ret; | |
257 | ||
258 | fd = socket(PF_INET, SOCK_STREAM, 0); | |
259 | if (fd < 0) { | |
260 | perror("socket"); | |
261 | return -1; | |
262 | } | |
263 | qemu_set_cloexec(fd); | |
264 | ||
265 | socket_set_fast_reuse(fd); | |
266 | ||
267 | sockaddr.sin_family = AF_INET; | |
268 | sockaddr.sin_port = htons(port); | |
269 | sockaddr.sin_addr.s_addr = 0; | |
270 | ret = bind(fd, (struct sockaddr *)&sockaddr, sizeof(sockaddr)); | |
271 | if (ret < 0) { | |
272 | perror("bind"); | |
273 | close(fd); | |
274 | return -1; | |
275 | } | |
276 | ret = listen(fd, 1); | |
277 | if (ret < 0) { | |
278 | perror("listen"); | |
279 | close(fd); | |
280 | return -1; | |
281 | } | |
282 | ||
283 | return fd; | |
284 | } | |
285 | ||
286 | int gdbserver_start(const char *port_or_path) | |
287 | { | |
288 | int port = g_ascii_strtoull(port_or_path, NULL, 10); | |
289 | int gdb_fd; | |
290 | ||
291 | if (port > 0) { | |
292 | gdb_fd = gdbserver_open_port(port); | |
293 | } else { | |
294 | gdb_fd = gdbserver_open_socket(port_or_path); | |
295 | } | |
296 | ||
297 | if (gdb_fd < 0) { | |
298 | return -1; | |
299 | } | |
300 | ||
301 | if (port > 0 && gdb_accept_tcp(gdb_fd)) { | |
302 | return 0; | |
303 | } else if (gdb_accept_socket(gdb_fd)) { | |
304 | gdbserver_user_state.socket_path = g_strdup(port_or_path); | |
305 | return 0; | |
306 | } | |
307 | ||
308 | /* gone wrong */ | |
309 | close(gdb_fd); | |
310 | return -1; | |
311 | } | |
312 | ||
313 | /* Disable gdb stub for child processes. */ | |
314 | void gdbserver_fork(CPUState *cpu) | |
315 | { | |
316 | if (!gdbserver_state.init || gdbserver_user_state.fd < 0) { | |
317 | return; | |
318 | } | |
319 | close(gdbserver_user_state.fd); | |
320 | gdbserver_user_state.fd = -1; | |
321 | cpu_breakpoint_remove_all(cpu, BP_GDB); | |
322 | /* no cpu_watchpoint_remove_all for user-mode */ | |
323 | } | |
324 | ||
325 | /* | |
326 | * Execution state helpers | |
327 | */ | |
328 | ||
329 | void gdb_continue(void) | |
330 | { | |
331 | gdbserver_user_state.running_state = 1; | |
332 | trace_gdbstub_op_continue(); | |
333 | } | |
334 | ||
335 | /* | |
336 | * Resume execution, for user-mode emulation it's equivalent to | |
337 | * gdb_continue. | |
338 | */ | |
339 | int gdb_continue_partial(char *newstates) | |
340 | { | |
341 | CPUState *cpu; | |
342 | int res = 0; | |
343 | /* | |
344 | * This is not exactly accurate, but it's an improvement compared to the | |
345 | * previous situation, where only one CPU would be single-stepped. | |
346 | */ | |
347 | CPU_FOREACH(cpu) { | |
348 | if (newstates[cpu->cpu_index] == 's') { | |
349 | trace_gdbstub_op_stepping(cpu->cpu_index); | |
350 | cpu_single_step(cpu, gdbserver_state.sstep_flags); | |
351 | } | |
352 | } | |
353 | gdbserver_user_state.running_state = 1; | |
354 | return res; | |
355 | } | |
356 | ||
357 | /* | |
358 | * Break/Watch point helpers | |
359 | */ | |
360 | ||
a48e7d9e AB |
361 | bool gdb_supports_guest_debug(void) |
362 | { | |
363 | /* user-mode == TCG == supported */ | |
364 | return true; | |
365 | } | |
366 | ||
55b5b8e9 | 367 | int gdb_breakpoint_insert(CPUState *cs, int type, vaddr addr, vaddr len) |
ae7467b1 AB |
368 | { |
369 | CPUState *cpu; | |
370 | int err = 0; | |
371 | ||
372 | switch (type) { | |
373 | case GDB_BREAKPOINT_SW: | |
374 | case GDB_BREAKPOINT_HW: | |
375 | CPU_FOREACH(cpu) { | |
376 | err = cpu_breakpoint_insert(cpu, addr, BP_GDB, NULL); | |
377 | if (err) { | |
378 | break; | |
379 | } | |
380 | } | |
381 | return err; | |
382 | default: | |
383 | /* user-mode doesn't support watchpoints */ | |
384 | return -ENOSYS; | |
385 | } | |
386 | } | |
387 | ||
55b5b8e9 | 388 | int gdb_breakpoint_remove(CPUState *cs, int type, vaddr addr, vaddr len) |
ae7467b1 AB |
389 | { |
390 | CPUState *cpu; | |
391 | int err = 0; | |
392 | ||
393 | switch (type) { | |
394 | case GDB_BREAKPOINT_SW: | |
395 | case GDB_BREAKPOINT_HW: | |
396 | CPU_FOREACH(cpu) { | |
397 | err = cpu_breakpoint_remove(cpu, addr, BP_GDB); | |
398 | if (err) { | |
399 | break; | |
400 | } | |
401 | } | |
402 | return err; | |
403 | default: | |
404 | /* user-mode doesn't support watchpoints */ | |
405 | return -ENOSYS; | |
406 | } | |
407 | } | |
408 | ||
409 | void gdb_breakpoint_remove_all(CPUState *cs) | |
410 | { | |
411 | cpu_breakpoint_remove_all(cs, BP_GDB); | |
412 | } |