Commit | Line | Data |
---|---|---|
176eb98c MS |
1 | /* GNU/Linux/AArch64 specific low level interface, for the remote server for |
2 | GDB. | |
3 | ||
4 | Copyright (C) 2009-2013 Free Software Foundation, Inc. | |
5 | Contributed by ARM Ltd. | |
6 | ||
7 | This file is part of GDB. | |
8 | ||
9 | This program is free software; you can redistribute it and/or modify | |
10 | it under the terms of the GNU General Public License as published by | |
11 | the Free Software Foundation; either version 3 of the License, or | |
12 | (at your option) any later version. | |
13 | ||
14 | This program is distributed in the hope that it will be useful, | |
15 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
16 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
17 | GNU General Public License for more details. | |
18 | ||
19 | You should have received a copy of the GNU General Public License | |
20 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ | |
21 | ||
22 | #include "server.h" | |
23 | #include "linux-low.h" | |
24 | #include "elf/common.h" | |
25 | ||
26 | #include <signal.h> | |
27 | #include <sys/user.h> | |
28 | #include <sys/ptrace.h> | |
29 | #include <sys/uio.h> | |
30 | ||
31 | #include "gdb_proc_service.h" | |
32 | ||
33 | /* Defined in auto-generated files. */ | |
34 | void init_registers_aarch64 (void); | |
35 | ||
176eb98c MS |
36 | #ifdef HAVE_SYS_REG_H |
37 | #include <sys/reg.h> | |
38 | #endif | |
39 | ||
40 | #define AARCH64_X_REGS_NUM 31 | |
41 | #define AARCH64_V_REGS_NUM 32 | |
42 | #define AARCH64_X0_REGNO 0 | |
43 | #define AARCH64_SP_REGNO 31 | |
44 | #define AARCH64_PC_REGNO 32 | |
45 | #define AARCH64_CPSR_REGNO 33 | |
46 | #define AARCH64_V0_REGNO 34 | |
47 | ||
48 | #define AARCH64_NUM_REGS (AARCH64_V0_REGNO + AARCH64_V_REGS_NUM) | |
49 | ||
50 | static int | |
51 | aarch64_regmap [] = | |
52 | { | |
53 | /* These offsets correspond to GET/SETREGSET */ | |
54 | /* x0... */ | |
55 | 0*8, 1*8, 2*8, 3*8, 4*8, 5*8, 6*8, 7*8, | |
56 | 8*8, 9*8, 10*8, 11*8, 12*8, 13*8, 14*8, 15*8, | |
57 | 16*8, 17*8, 18*8, 19*8, 20*8, 21*8, 22*8, 23*8, | |
58 | 24*8, 25*8, 26*8, 27*8, 28*8, | |
59 | 29*8, | |
60 | 30*8, /* x30 lr */ | |
61 | 31*8, /* x31 sp */ | |
62 | 32*8, /* pc */ | |
63 | 33*8, /* cpsr 4 bytes!*/ | |
64 | ||
65 | /* FP register offsets correspond to GET/SETFPREGSET */ | |
66 | 0*16, 1*16, 2*16, 3*16, 4*16, 5*16, 6*16, 7*16, | |
67 | 8*16, 9*16, 10*16, 11*16, 12*16, 13*16, 14*16, 15*16, | |
68 | 16*16, 17*16, 18*16, 19*16, 20*16, 21*16, 22*16, 23*16, | |
69 | 24*16, 25*16, 26*16, 27*16, 28*16, 29*16, 30*16, 31*16 | |
70 | }; | |
71 | ||
72 | /* Here starts the macro definitions, data structures, and code for | |
73 | the hardware breakpoint and hardware watchpoint support. The | |
74 | following is the abbreviations that are used frequently in the code | |
75 | and comment: | |
76 | ||
77 | hw - hardware | |
78 | bp - breakpoint | |
79 | wp - watchpoint */ | |
80 | ||
81 | /* Maximum number of hardware breakpoint and watchpoint registers. | |
82 | Neither of these values may exceed the width of dr_changed_t | |
83 | measured in bits. */ | |
84 | ||
85 | #define AARCH64_HBP_MAX_NUM 16 | |
86 | #define AARCH64_HWP_MAX_NUM 16 | |
87 | ||
88 | /* Alignment requirement in bytes of hardware breakpoint and | |
89 | watchpoint address. This is the requirement for the addresses that | |
90 | can be written to the hardware breakpoint/watchpoint value | |
91 | registers. The kernel currently does not do any alignment on | |
92 | addresses when receiving a writing request (via ptrace call) to | |
93 | these debug registers, and it will reject any address that is | |
94 | unaligned. | |
95 | Some limited support has been provided in this gdbserver port for | |
96 | unaligned watchpoints, so that from a gdb user point of view, an | |
97 | unaligned watchpoint can still be set. This is achieved by | |
98 | minimally enlarging the watched area to meet the alignment | |
99 | requirement, and if necessary, splitting the watchpoint over | |
100 | several hardware watchpoint registers. */ | |
101 | ||
102 | #define AARCH64_HBP_ALIGNMENT 4 | |
103 | #define AARCH64_HWP_ALIGNMENT 8 | |
104 | ||
105 | /* The maximum length of a memory region that can be watched by one | |
106 | hardware watchpoint register. */ | |
107 | ||
108 | #define AARCH64_HWP_MAX_LEN_PER_REG 8 | |
109 | ||
110 | /* Each bit of a variable of this type is used to indicate whether a | |
111 | hardware breakpoint or watchpoint setting has been changed since | |
112 | the last updating. Bit N corresponds to the Nth hardware | |
113 | breakpoint or watchpoint setting which is managed in | |
114 | aarch64_debug_reg_state. Where N is valid between 0 and the total | |
115 | number of the hardware breakpoint or watchpoint debug registers | |
116 | minus 1. When the bit N is 1, it indicates the corresponding | |
117 | breakpoint or watchpoint setting is changed, and thus the | |
118 | corresponding hardware debug register needs to be updated via the | |
119 | ptrace interface. | |
120 | ||
121 | In the per-thread arch-specific data area, we define two such | |
122 | variables for per-thread hardware breakpoint and watchpoint | |
123 | settings respectively. | |
124 | ||
125 | This type is part of the mechanism which helps reduce the number of | |
126 | ptrace calls to the kernel, i.e. avoid asking the kernel to write | |
127 | to the debug registers with unchanged values. */ | |
128 | ||
129 | typedef unsigned long long dr_changed_t; | |
130 | ||
131 | /* Set each of the lower M bits of X to 1; assert X is wide enough. */ | |
132 | ||
133 | #define DR_MARK_ALL_CHANGED(x, m) \ | |
134 | do \ | |
135 | { \ | |
136 | gdb_assert (sizeof ((x)) * 8 >= (m)); \ | |
137 | (x) = (((dr_changed_t)1 << (m)) - 1); \ | |
138 | } while (0) | |
139 | ||
140 | #define DR_MARK_N_CHANGED(x, n) \ | |
141 | do \ | |
142 | { \ | |
143 | (x) |= ((dr_changed_t)1 << (n)); \ | |
144 | } while (0) | |
145 | ||
146 | #define DR_CLEAR_CHANGED(x) \ | |
147 | do \ | |
148 | { \ | |
149 | (x) = 0; \ | |
150 | } while (0) | |
151 | ||
152 | #define DR_HAS_CHANGED(x) ((x) != 0) | |
153 | #define DR_N_HAS_CHANGED(x, n) ((x) & ((dr_changed_t)1 << (n))) | |
154 | ||
155 | /* Structure for managing the hardware breakpoint/watchpoint resources. | |
156 | DR_ADDR_* stores the address, DR_CTRL_* stores the control register | |
157 | content, and DR_REF_COUNT_* counts the numbers of references to the | |
158 | corresponding bp/wp, by which way the limited hardware resources | |
159 | are not wasted on duplicated bp/wp settings (though so far gdb has | |
160 | done a good job by not sending duplicated bp/wp requests). */ | |
161 | ||
162 | struct aarch64_debug_reg_state | |
163 | { | |
164 | /* hardware breakpoint */ | |
165 | CORE_ADDR dr_addr_bp[AARCH64_HBP_MAX_NUM]; | |
166 | unsigned int dr_ctrl_bp[AARCH64_HBP_MAX_NUM]; | |
167 | unsigned int dr_ref_count_bp[AARCH64_HBP_MAX_NUM]; | |
168 | ||
169 | /* hardware watchpoint */ | |
170 | CORE_ADDR dr_addr_wp[AARCH64_HWP_MAX_NUM]; | |
171 | unsigned int dr_ctrl_wp[AARCH64_HWP_MAX_NUM]; | |
172 | unsigned int dr_ref_count_wp[AARCH64_HWP_MAX_NUM]; | |
173 | }; | |
174 | ||
175 | /* Per-process arch-specific data we want to keep. */ | |
176 | ||
177 | struct arch_process_info | |
178 | { | |
179 | /* Hardware breakpoint/watchpoint data. | |
180 | The reason for them to be per-process rather than per-thread is | |
181 | due to the lack of information in the gdbserver environment; | |
182 | gdbserver is not told that whether a requested hardware | |
183 | breakpoint/watchpoint is thread specific or not, so it has to set | |
184 | each hw bp/wp for every thread in the current process. The | |
185 | higher level bp/wp management in gdb will resume a thread if a hw | |
186 | bp/wp trap is not expected for it. Since the hw bp/wp setting is | |
187 | same for each thread, it is reasonable for the data to live here. | |
188 | */ | |
189 | struct aarch64_debug_reg_state debug_reg_state; | |
190 | }; | |
191 | ||
192 | /* Per-thread arch-specific data we want to keep. */ | |
193 | ||
194 | struct arch_lwp_info | |
195 | { | |
196 | /* When bit N is 1, it indicates the Nth hardware breakpoint or | |
197 | watchpoint register pair needs to be updated when the thread is | |
198 | resumed; see aarch64_linux_prepare_to_resume. */ | |
199 | dr_changed_t dr_changed_bp; | |
200 | dr_changed_t dr_changed_wp; | |
201 | }; | |
202 | ||
203 | /* Number of hardware breakpoints/watchpoints the target supports. | |
204 | They are initialized with values obtained via the ptrace calls | |
205 | with NT_ARM_HW_BREAK and NT_ARM_HW_WATCH respectively. */ | |
206 | ||
207 | static int aarch64_num_bp_regs; | |
208 | static int aarch64_num_wp_regs; | |
209 | ||
210 | /* Hardware breakpoint/watchpoint types. | |
211 | The values map to their encodings in the bit 4 and bit 3 of the | |
212 | hardware breakpoint/watchpoint control registers. */ | |
213 | ||
214 | enum target_point_type | |
215 | { | |
216 | hw_execute = 0, /* Execute HW breakpoint */ | |
217 | hw_read = 1, /* Read HW watchpoint */ | |
218 | hw_write = 2, /* Common HW watchpoint */ | |
219 | hw_access = 3, /* Access HW watchpoint */ | |
220 | point_type_unsupported | |
221 | }; | |
222 | ||
223 | #define Z_PACKET_SW_BP '0' | |
224 | #define Z_PACKET_HW_BP '1' | |
225 | #define Z_PACKET_WRITE_WP '2' | |
226 | #define Z_PACKET_READ_WP '3' | |
227 | #define Z_PACKET_ACCESS_WP '4' | |
228 | ||
229 | /* Map the protocol breakpoint/watchpoint type TYPE to | |
230 | enum target_point_type. */ | |
231 | ||
232 | static enum target_point_type | |
233 | Z_packet_to_point_type (char type) | |
234 | { | |
235 | switch (type) | |
236 | { | |
237 | case Z_PACKET_SW_BP: | |
238 | /* Leave the handling of the sw breakpoint with the gdb client. */ | |
239 | return point_type_unsupported; | |
240 | case Z_PACKET_HW_BP: | |
241 | return hw_execute; | |
242 | case Z_PACKET_WRITE_WP: | |
243 | return hw_write; | |
244 | case Z_PACKET_READ_WP: | |
245 | return hw_read; | |
246 | case Z_PACKET_ACCESS_WP: | |
247 | return hw_access; | |
248 | default: | |
249 | return point_type_unsupported; | |
250 | } | |
251 | } | |
252 | ||
253 | static int | |
254 | aarch64_cannot_store_register (int regno) | |
255 | { | |
256 | return regno >= AARCH64_NUM_REGS; | |
257 | } | |
258 | ||
259 | static int | |
260 | aarch64_cannot_fetch_register (int regno) | |
261 | { | |
262 | return regno >= AARCH64_NUM_REGS; | |
263 | } | |
264 | ||
265 | static void | |
266 | aarch64_fill_gregset (struct regcache *regcache, void *buf) | |
267 | { | |
268 | struct user_pt_regs *regset = buf; | |
269 | int i; | |
270 | ||
271 | for (i = 0; i < AARCH64_X_REGS_NUM; i++) | |
272 | collect_register (regcache, AARCH64_X0_REGNO + i, ®set->regs[i]); | |
273 | collect_register (regcache, AARCH64_SP_REGNO, ®set->sp); | |
274 | collect_register (regcache, AARCH64_PC_REGNO, ®set->pc); | |
275 | collect_register (regcache, AARCH64_CPSR_REGNO, ®set->pstate); | |
276 | } | |
277 | ||
278 | static void | |
279 | aarch64_store_gregset (struct regcache *regcache, const void *buf) | |
280 | { | |
281 | const struct user_pt_regs *regset = buf; | |
282 | int i; | |
283 | ||
284 | for (i = 0; i < AARCH64_X_REGS_NUM; i++) | |
285 | supply_register (regcache, AARCH64_X0_REGNO + i, ®set->regs[i]); | |
286 | supply_register (regcache, AARCH64_SP_REGNO, ®set->sp); | |
287 | supply_register (regcache, AARCH64_PC_REGNO, ®set->pc); | |
288 | supply_register (regcache, AARCH64_CPSR_REGNO, ®set->pstate); | |
289 | } | |
290 | ||
291 | static void | |
292 | aarch64_fill_fpregset (struct regcache *regcache, void *buf) | |
293 | { | |
294 | struct user_fpsimd_state *regset = buf; | |
295 | int i; | |
296 | ||
297 | for (i = 0; i < AARCH64_V_REGS_NUM; i++) | |
298 | collect_register (regcache, AARCH64_V0_REGNO + i, ®set->vregs[i]); | |
299 | } | |
300 | ||
301 | static void | |
302 | aarch64_store_fpregset (struct regcache *regcache, const void *buf) | |
303 | { | |
304 | const struct user_fpsimd_state *regset = buf; | |
305 | int i; | |
306 | ||
307 | for (i = 0; i < AARCH64_V_REGS_NUM; i++) | |
308 | supply_register (regcache, AARCH64_V0_REGNO + i, ®set->vregs[i]); | |
309 | } | |
310 | ||
311 | /* Debugging of hardware breakpoint/watchpoint support. */ | |
312 | extern int debug_hw_points; | |
313 | ||
314 | /* Enable miscellaneous debugging output. The name is historical - it | |
315 | was originally used to debug LinuxThreads support. */ | |
316 | extern int debug_threads; | |
317 | ||
318 | static CORE_ADDR | |
319 | aarch64_get_pc (struct regcache *regcache) | |
320 | { | |
321 | unsigned long pc; | |
322 | ||
323 | collect_register_by_name (regcache, "pc", &pc); | |
324 | if (debug_threads) | |
325 | fprintf (stderr, "stop pc is %08lx\n", pc); | |
326 | return pc; | |
327 | } | |
328 | ||
329 | static void | |
330 | aarch64_set_pc (struct regcache *regcache, CORE_ADDR pc) | |
331 | { | |
332 | unsigned long newpc = pc; | |
333 | supply_register_by_name (regcache, "pc", &newpc); | |
334 | } | |
335 | ||
336 | /* Correct in either endianness. */ | |
337 | ||
338 | #define aarch64_breakpoint_len 4 | |
339 | ||
340 | static const unsigned long aarch64_breakpoint = 0x00800011; | |
341 | ||
342 | static int | |
343 | aarch64_breakpoint_at (CORE_ADDR where) | |
344 | { | |
345 | unsigned long insn; | |
346 | ||
347 | (*the_target->read_memory) (where, (unsigned char *) &insn, 4); | |
348 | if (insn == aarch64_breakpoint) | |
349 | return 1; | |
350 | ||
351 | return 0; | |
352 | } | |
353 | ||
354 | /* Print the values of the cached breakpoint/watchpoint registers. | |
355 | This is enabled via the "set debug-hw-points" monitor command. */ | |
356 | ||
357 | static void | |
358 | aarch64_show_debug_reg_state (struct aarch64_debug_reg_state *state, | |
359 | const char *func, CORE_ADDR addr, | |
360 | int len, enum target_point_type type) | |
361 | { | |
362 | int i; | |
363 | ||
364 | fprintf (stderr, "%s", func); | |
365 | if (addr || len) | |
366 | fprintf (stderr, " (addr=0x%08lx, len=%d, type=%s)", | |
367 | (unsigned long) addr, len, | |
368 | type == hw_write ? "hw-write-watchpoint" | |
369 | : (type == hw_read ? "hw-read-watchpoint" | |
370 | : (type == hw_access ? "hw-access-watchpoint" | |
371 | : (type == hw_execute ? "hw-breakpoint" | |
372 | : "??unknown??")))); | |
373 | fprintf (stderr, ":\n"); | |
374 | ||
375 | fprintf (stderr, "\tBREAKPOINTs:\n"); | |
376 | for (i = 0; i < aarch64_num_bp_regs; i++) | |
377 | fprintf (stderr, "\tBP%d: addr=0x%s, ctrl=0x%08x, ref.count=%d\n", | |
378 | i, paddress (state->dr_addr_bp[i]), | |
379 | state->dr_ctrl_bp[i], state->dr_ref_count_bp[i]); | |
380 | ||
381 | fprintf (stderr, "\tWATCHPOINTs:\n"); | |
382 | for (i = 0; i < aarch64_num_wp_regs; i++) | |
383 | fprintf (stderr, "\tWP%d: addr=0x%s, ctrl=0x%08x, ref.count=%d\n", | |
384 | i, paddress (state->dr_addr_wp[i]), | |
385 | state->dr_ctrl_wp[i], state->dr_ref_count_wp[i]); | |
386 | } | |
387 | ||
388 | static void | |
389 | aarch64_init_debug_reg_state (struct aarch64_debug_reg_state *state) | |
390 | { | |
391 | int i; | |
392 | ||
393 | for (i = 0; i < AARCH64_HBP_MAX_NUM; ++i) | |
394 | { | |
395 | state->dr_addr_bp[i] = 0; | |
396 | state->dr_ctrl_bp[i] = 0; | |
397 | state->dr_ref_count_bp[i] = 0; | |
398 | } | |
399 | ||
400 | for (i = 0; i < AARCH64_HWP_MAX_NUM; ++i) | |
401 | { | |
402 | state->dr_addr_wp[i] = 0; | |
403 | state->dr_ctrl_wp[i] = 0; | |
404 | state->dr_ref_count_wp[i] = 0; | |
405 | } | |
406 | } | |
407 | ||
408 | /* ptrace expects control registers to be formatted as follows: | |
409 | ||
410 | 31 13 5 3 1 0 | |
411 | +--------------------------------+----------+------+------+----+ | |
412 | | RESERVED (SBZ) | LENGTH | TYPE | PRIV | EN | | |
413 | +--------------------------------+----------+------+------+----+ | |
414 | ||
415 | The TYPE field is ignored for breakpoints. */ | |
416 | ||
417 | #define DR_CONTROL_ENABLED(ctrl) (((ctrl) & 0x1) == 1) | |
418 | #define DR_CONTROL_LENGTH(ctrl) (((ctrl) >> 5) & 0xff) | |
419 | ||
420 | /* Utility function that returns the length in bytes of a watchpoint | |
421 | according to the content of a hardware debug control register CTRL. | |
422 | Note that the kernel currently only supports the following Byte | |
423 | Address Select (BAS) values: 0x1, 0x3, 0xf and 0xff, which means | |
424 | that for a hardware watchpoint, its valid length can only be 1 | |
425 | byte, 2 bytes, 4 bytes or 8 bytes. */ | |
426 | ||
427 | static inline unsigned int | |
428 | aarch64_watchpoint_length (unsigned int ctrl) | |
429 | { | |
430 | switch (DR_CONTROL_LENGTH (ctrl)) | |
431 | { | |
432 | case 0x01: | |
433 | return 1; | |
434 | case 0x03: | |
435 | return 2; | |
436 | case 0x0f: | |
437 | return 4; | |
438 | case 0xff: | |
439 | return 8; | |
440 | default: | |
441 | return 0; | |
442 | } | |
443 | } | |
444 | ||
445 | /* Given the hardware breakpoint or watchpoint type TYPE and its | |
446 | length LEN, return the expected encoding for a hardware | |
447 | breakpoint/watchpoint control register. */ | |
448 | ||
449 | static unsigned int | |
450 | aarch64_point_encode_ctrl_reg (enum target_point_type type, int len) | |
451 | { | |
452 | unsigned int ctrl; | |
453 | ||
454 | /* type */ | |
455 | ctrl = type << 3; | |
456 | /* length bitmask */ | |
457 | ctrl |= ((1 << len) - 1) << 5; | |
458 | /* enabled at el0 */ | |
459 | ctrl |= (2 << 1) | 1; | |
460 | ||
461 | return ctrl; | |
462 | } | |
463 | ||
464 | /* Addresses to be written to the hardware breakpoint and watchpoint | |
465 | value registers need to be aligned; the alignment is 4-byte and | |
466 | 8-type respectively. Linux kernel rejects any non-aligned address | |
467 | it receives from the related ptrace call. Furthermore, the kernel | |
468 | currently only supports the following Byte Address Select (BAS) | |
469 | values: 0x1, 0x3, 0xf and 0xff, which means that for a hardware | |
470 | watchpoint to be accepted by the kernel (via ptrace call), its | |
471 | valid length can only be 1 byte, 2 bytes, 4 bytes or 8 bytes. | |
472 | Despite these limitations, the unaligned watchpoint is supported in | |
473 | this gdbserver port. | |
474 | ||
475 | Return 0 for any non-compliant ADDR and/or LEN; return 1 otherwise. */ | |
476 | ||
477 | static int | |
478 | aarch64_point_is_aligned (int is_watchpoint, CORE_ADDR addr, int len) | |
479 | { | |
480 | unsigned int alignment = is_watchpoint ? AARCH64_HWP_ALIGNMENT | |
481 | : AARCH64_HBP_ALIGNMENT; | |
482 | ||
483 | if (addr & (alignment - 1)) | |
484 | return 0; | |
485 | ||
486 | if (len != 8 && len != 4 && len != 2 && len != 1) | |
487 | return 0; | |
488 | ||
489 | return 1; | |
490 | } | |
491 | ||
492 | /* Given the (potentially unaligned) watchpoint address in ADDR and | |
493 | length in LEN, return the aligned address and aligned length in | |
494 | *ALIGNED_ADDR_P and *ALIGNED_LEN_P, respectively. The returned | |
495 | aligned address and length will be valid to be written to the | |
496 | hardware watchpoint value and control registers. See the comment | |
497 | above aarch64_point_is_aligned for the information about the | |
498 | alignment requirement. The given watchpoint may get truncated if | |
499 | more than one hardware register is needed to cover the watched | |
500 | region. *NEXT_ADDR_P and *NEXT_LEN_P, if non-NULL, will return the | |
501 | address and length of the remaining part of the watchpoint (which | |
502 | can be processed by calling this routine again to generate another | |
503 | aligned address and length pair. | |
504 | ||
505 | Essentially, unaligned watchpoint is achieved by minimally | |
506 | enlarging the watched area to meet the alignment requirement, and | |
507 | if necessary, splitting the watchpoint over several hardware | |
508 | watchpoint registers. The trade-off is that there will be | |
509 | false-positive hits for the read-type or the access-type hardware | |
510 | watchpoints; for the write type, which is more commonly used, there | |
511 | will be no such issues, as the higher-level breakpoint management | |
512 | in gdb always examines the exact watched region for any content | |
513 | change, and transparently resumes a thread from a watchpoint trap | |
514 | if there is no change to the watched region. | |
515 | ||
516 | Another limitation is that because the watched region is enlarged, | |
517 | the watchpoint fault address returned by | |
518 | aarch64_stopped_data_address may be outside of the original watched | |
519 | region, especially when the triggering instruction is accessing a | |
520 | larger region. When the fault address is not within any known | |
521 | range, watchpoints_triggered in gdb will get confused, as the | |
522 | higher-level watchpoint management is only aware of original | |
523 | watched regions, and will think that some unknown watchpoint has | |
524 | been triggered. In such a case, gdb may stop without displaying | |
525 | any detailed information. | |
526 | ||
527 | Once the kernel provides the full support for Byte Address Select | |
528 | (BAS) in the hardware watchpoint control register, these | |
529 | limitations can be largely relaxed with some further work. */ | |
530 | ||
531 | static void | |
532 | aarch64_align_watchpoint (CORE_ADDR addr, int len, CORE_ADDR *aligned_addr_p, | |
533 | int *aligned_len_p, CORE_ADDR *next_addr_p, | |
534 | int *next_len_p) | |
535 | { | |
536 | int aligned_len; | |
537 | unsigned int offset; | |
538 | CORE_ADDR aligned_addr; | |
539 | const unsigned int alignment = AARCH64_HWP_ALIGNMENT; | |
540 | const unsigned int max_wp_len = AARCH64_HWP_MAX_LEN_PER_REG; | |
541 | ||
542 | /* As assumed by the algorithm. */ | |
543 | gdb_assert (alignment == max_wp_len); | |
544 | ||
545 | if (len <= 0) | |
546 | return; | |
547 | ||
548 | /* Address to be put into the hardware watchpoint value register | |
549 | must be aligned. */ | |
550 | offset = addr & (alignment - 1); | |
551 | aligned_addr = addr - offset; | |
552 | ||
553 | gdb_assert (offset >= 0 && offset < alignment); | |
554 | gdb_assert (aligned_addr >= 0 && aligned_addr <= addr); | |
555 | gdb_assert ((offset + len) > 0); | |
556 | ||
557 | if (offset + len >= max_wp_len) | |
558 | { | |
559 | /* Need more than one watchpoint registers; truncate it at the | |
560 | alignment boundary. */ | |
561 | aligned_len = max_wp_len; | |
562 | len -= (max_wp_len - offset); | |
563 | addr += (max_wp_len - offset); | |
564 | gdb_assert ((addr & (alignment - 1)) == 0); | |
565 | } | |
566 | else | |
567 | { | |
568 | /* Find the smallest valid length that is large enough to | |
569 | accommodate this watchpoint. */ | |
570 | static const unsigned char | |
571 | aligned_len_array[AARCH64_HWP_MAX_LEN_PER_REG] = | |
572 | { 1, 2, 4, 4, 8, 8, 8, 8 }; | |
573 | ||
574 | aligned_len = aligned_len_array[offset + len - 1]; | |
575 | addr += len; | |
576 | len = 0; | |
577 | } | |
578 | ||
579 | if (aligned_addr_p != NULL) | |
580 | *aligned_addr_p = aligned_addr; | |
581 | if (aligned_len_p != NULL) | |
582 | *aligned_len_p = aligned_len; | |
583 | if (next_addr_p != NULL) | |
584 | *next_addr_p = addr; | |
585 | if (next_len_p != NULL) | |
586 | *next_len_p = len; | |
587 | } | |
588 | ||
589 | /* Call ptrace to set the thread TID's hardware breakpoint/watchpoint | |
590 | registers with data from *STATE. */ | |
591 | ||
592 | static void | |
593 | aarch64_linux_set_debug_regs (const struct aarch64_debug_reg_state *state, | |
594 | int tid, int watchpoint) | |
595 | { | |
596 | int i, count; | |
597 | struct iovec iov; | |
598 | struct user_hwdebug_state regs; | |
599 | const CORE_ADDR *addr; | |
600 | const unsigned int *ctrl; | |
601 | ||
602 | iov.iov_base = ®s; | |
603 | iov.iov_len = sizeof (regs); | |
604 | count = watchpoint ? aarch64_num_wp_regs : aarch64_num_bp_regs; | |
605 | addr = watchpoint ? state->dr_addr_wp : state->dr_addr_bp; | |
606 | ctrl = watchpoint ? state->dr_ctrl_wp : state->dr_ctrl_bp; | |
607 | ||
608 | for (i = 0; i < count; i++) | |
609 | { | |
610 | regs.dbg_regs[i].addr = addr[i]; | |
611 | regs.dbg_regs[i].ctrl = ctrl[i]; | |
612 | } | |
613 | ||
614 | if (ptrace (PTRACE_SETREGSET, tid, | |
615 | watchpoint ? NT_ARM_HW_WATCH : NT_ARM_HW_BREAK, | |
616 | (void *) &iov)) | |
617 | error (_("Unexpected error setting hardware debug registers")); | |
618 | } | |
619 | ||
620 | struct aarch64_dr_update_callback_param | |
621 | { | |
622 | int pid; | |
623 | int is_watchpoint; | |
624 | unsigned int idx; | |
625 | }; | |
626 | ||
627 | /* Callback function which records the information about the change of | |
628 | one hardware breakpoint/watchpoint setting for the thread ENTRY. | |
629 | The information is passed in via PTR. | |
630 | N.B. The actual updating of hardware debug registers is not | |
631 | carried out until the moment the thread is resumed. */ | |
632 | ||
633 | static int | |
634 | debug_reg_change_callback (struct inferior_list_entry *entry, void *ptr) | |
635 | { | |
636 | struct lwp_info *lwp = (struct lwp_info *) entry; | |
637 | struct aarch64_dr_update_callback_param *param_p | |
638 | = (struct aarch64_dr_update_callback_param *) ptr; | |
639 | int pid = param_p->pid; | |
640 | int idx = param_p->idx; | |
641 | int is_watchpoint = param_p->is_watchpoint; | |
642 | struct arch_lwp_info *info = lwp->arch_private; | |
643 | dr_changed_t *dr_changed_ptr; | |
644 | dr_changed_t dr_changed; | |
645 | ||
646 | if (debug_hw_points) | |
647 | { | |
648 | fprintf (stderr, "debug_reg_change_callback: \n\tOn entry:\n"); | |
649 | fprintf (stderr, "\tpid%d, tid: %ld, dr_changed_bp=0x%llx, " | |
650 | "dr_changed_wp=0x%llx\n", | |
651 | pid, lwpid_of (lwp), info->dr_changed_bp, | |
652 | info->dr_changed_wp); | |
653 | } | |
654 | ||
655 | dr_changed_ptr = is_watchpoint ? &info->dr_changed_wp | |
656 | : &info->dr_changed_bp; | |
657 | dr_changed = *dr_changed_ptr; | |
658 | ||
659 | /* Only update the threads of this process. */ | |
660 | if (pid_of (lwp) == pid) | |
661 | { | |
662 | gdb_assert (idx >= 0 | |
663 | && (idx <= (is_watchpoint ? aarch64_num_wp_regs | |
664 | : aarch64_num_bp_regs))); | |
665 | ||
666 | /* The following assertion is not right, as there can be changes | |
667 | that have not been made to the hardware debug registers | |
668 | before new changes overwrite the old ones. This can happen, | |
669 | for instance, when the breakpoint/watchpoint hit one of the | |
670 | threads and the user enters continue; then what happens is: | |
671 | 1) all breakpoints/watchpoints are removed for all threads; | |
672 | 2) a single step is carried out for the thread that was hit; | |
673 | 3) all of the points are inserted again for all threads; | |
674 | 4) all threads are resumed. | |
675 | The 2nd step will only affect the one thread in which the | |
676 | bp/wp was hit, which means only that one thread is resumed; | |
677 | remember that the actual updating only happen in | |
678 | aarch64_linux_prepare_to_resume, so other threads remain | |
679 | stopped during the removal and insertion of bp/wp. Therefore | |
680 | for those threads, the change of insertion of the bp/wp | |
681 | overwrites that of the earlier removals. (The situation may | |
682 | be different when bp/wp is steppable, or in the non-stop | |
683 | mode.) */ | |
684 | /* gdb_assert (DR_N_HAS_CHANGED (dr_changed, idx) == 0); */ | |
685 | ||
686 | /* The actual update is done later just before resuming the lwp, | |
687 | we just mark that one register pair needs updating. */ | |
688 | DR_MARK_N_CHANGED (dr_changed, idx); | |
689 | *dr_changed_ptr = dr_changed; | |
690 | ||
691 | /* If the lwp isn't stopped, force it to momentarily pause, so | |
692 | we can update its debug registers. */ | |
693 | if (!lwp->stopped) | |
694 | linux_stop_lwp (lwp); | |
695 | } | |
696 | ||
697 | if (debug_hw_points) | |
698 | { | |
699 | fprintf (stderr, "\tOn exit:\n\tpid%d, tid: %ld, dr_changed_bp=0x%llx, " | |
700 | "dr_changed_wp=0x%llx\n", | |
701 | pid, lwpid_of (lwp), info->dr_changed_bp, info->dr_changed_wp); | |
702 | } | |
703 | ||
704 | return 0; | |
705 | } | |
706 | ||
707 | /* Notify each thread that their IDXth breakpoint/watchpoint register | |
708 | pair needs to be updated. The message will be recorded in each | |
709 | thread's arch-specific data area, the actual updating will be done | |
710 | when the thread is resumed. */ | |
711 | ||
712 | void | |
713 | aarch64_notify_debug_reg_change (const struct aarch64_debug_reg_state *state, | |
714 | int is_watchpoint, unsigned int idx) | |
715 | { | |
716 | struct aarch64_dr_update_callback_param param; | |
717 | ||
718 | /* Only update the threads of this process. */ | |
719 | param.pid = pid_of (get_thread_lwp (current_inferior)); | |
720 | ||
721 | param.is_watchpoint = is_watchpoint; | |
722 | param.idx = idx; | |
723 | ||
724 | find_inferior (&all_lwps, debug_reg_change_callback, (void *) ¶m); | |
725 | } | |
726 | ||
727 | ||
728 | /* Return the pointer to the debug register state structure in the | |
729 | current process' arch-specific data area. */ | |
730 | ||
731 | static struct aarch64_debug_reg_state * | |
732 | aarch64_get_debug_reg_state () | |
733 | { | |
734 | struct process_info *proc; | |
735 | ||
736 | proc = current_process (); | |
737 | return &proc->private->arch_private->debug_reg_state; | |
738 | } | |
739 | ||
740 | /* Record the insertion of one breakpoint/watchpoint, as represented | |
741 | by ADDR and CTRL, in the process' arch-specific data area *STATE. */ | |
742 | ||
743 | static int | |
744 | aarch64_dr_state_insert_one_point (struct aarch64_debug_reg_state *state, | |
745 | enum target_point_type type, | |
746 | CORE_ADDR addr, int len) | |
747 | { | |
748 | int i, idx, num_regs, is_watchpoint; | |
749 | unsigned int ctrl, *dr_ctrl_p, *dr_ref_count; | |
750 | CORE_ADDR *dr_addr_p; | |
751 | ||
752 | /* Set up state pointers. */ | |
753 | is_watchpoint = (type != hw_execute); | |
754 | gdb_assert (aarch64_point_is_aligned (is_watchpoint, addr, len)); | |
755 | if (is_watchpoint) | |
756 | { | |
757 | num_regs = aarch64_num_wp_regs; | |
758 | dr_addr_p = state->dr_addr_wp; | |
759 | dr_ctrl_p = state->dr_ctrl_wp; | |
760 | dr_ref_count = state->dr_ref_count_wp; | |
761 | } | |
762 | else | |
763 | { | |
764 | num_regs = aarch64_num_bp_regs; | |
765 | dr_addr_p = state->dr_addr_bp; | |
766 | dr_ctrl_p = state->dr_ctrl_bp; | |
767 | dr_ref_count = state->dr_ref_count_bp; | |
768 | } | |
769 | ||
770 | ctrl = aarch64_point_encode_ctrl_reg (type, len); | |
771 | ||
772 | /* Find an existing or free register in our cache. */ | |
773 | idx = -1; | |
774 | for (i = 0; i < num_regs; ++i) | |
775 | { | |
776 | if ((dr_ctrl_p[i] & 1) == 0) | |
777 | { | |
778 | gdb_assert (dr_ref_count[i] == 0); | |
779 | idx = i; | |
780 | /* no break; continue hunting for an exising one. */ | |
781 | } | |
782 | else if (dr_addr_p[i] == addr && dr_ctrl_p[i] == ctrl) | |
783 | { | |
784 | gdb_assert (dr_ref_count[i] != 0); | |
785 | idx = i; | |
786 | break; | |
787 | } | |
788 | } | |
789 | ||
790 | /* No space. */ | |
791 | if (idx == -1) | |
792 | return -1; | |
793 | ||
794 | /* Update our cache. */ | |
795 | if ((dr_ctrl_p[idx] & 1) == 0) | |
796 | { | |
797 | /* new entry */ | |
798 | dr_addr_p[idx] = addr; | |
799 | dr_ctrl_p[idx] = ctrl; | |
800 | dr_ref_count[idx] = 1; | |
801 | /* Notify the change. */ | |
802 | aarch64_notify_debug_reg_change (state, is_watchpoint, idx); | |
803 | } | |
804 | else | |
805 | { | |
806 | /* existing entry */ | |
807 | dr_ref_count[idx]++; | |
808 | } | |
809 | ||
810 | return 0; | |
811 | } | |
812 | ||
813 | /* Record the removal of one breakpoint/watchpoint, as represented by | |
814 | ADDR and CTRL, in the process' arch-specific data area *STATE. */ | |
815 | ||
816 | static int | |
817 | aarch64_dr_state_remove_one_point (struct aarch64_debug_reg_state *state, | |
818 | enum target_point_type type, | |
819 | CORE_ADDR addr, int len) | |
820 | { | |
821 | int i, num_regs, is_watchpoint; | |
822 | unsigned int ctrl, *dr_ctrl_p, *dr_ref_count; | |
823 | CORE_ADDR *dr_addr_p; | |
824 | ||
825 | /* Set up state pointers. */ | |
826 | is_watchpoint = (type != hw_execute); | |
827 | gdb_assert (aarch64_point_is_aligned (is_watchpoint, addr, len)); | |
828 | if (is_watchpoint) | |
829 | { | |
830 | num_regs = aarch64_num_wp_regs; | |
831 | dr_addr_p = state->dr_addr_wp; | |
832 | dr_ctrl_p = state->dr_ctrl_wp; | |
833 | dr_ref_count = state->dr_ref_count_wp; | |
834 | } | |
835 | else | |
836 | { | |
837 | num_regs = aarch64_num_bp_regs; | |
838 | dr_addr_p = state->dr_addr_bp; | |
839 | dr_ctrl_p = state->dr_ctrl_bp; | |
840 | dr_ref_count = state->dr_ref_count_bp; | |
841 | } | |
842 | ||
843 | ctrl = aarch64_point_encode_ctrl_reg (type, len); | |
844 | ||
845 | /* Find the entry that matches the ADDR and CTRL. */ | |
846 | for (i = 0; i < num_regs; ++i) | |
847 | if (dr_addr_p[i] == addr && dr_ctrl_p[i] == ctrl) | |
848 | { | |
849 | gdb_assert (dr_ref_count[i] != 0); | |
850 | break; | |
851 | } | |
852 | ||
853 | /* Not found. */ | |
854 | if (i == num_regs) | |
855 | return -1; | |
856 | ||
857 | /* Clear our cache. */ | |
858 | if (--dr_ref_count[i] == 0) | |
859 | { | |
860 | /* Clear the enable bit. */ | |
861 | ctrl &= ~1; | |
862 | dr_addr_p[i] = 0; | |
863 | dr_ctrl_p[i] = ctrl; | |
864 | /* Notify the change. */ | |
865 | aarch64_notify_debug_reg_change (state, is_watchpoint, i); | |
866 | } | |
867 | ||
868 | return 0; | |
869 | } | |
870 | ||
871 | static int | |
872 | aarch64_handle_breakpoint (enum target_point_type type, CORE_ADDR addr, | |
873 | int len, int is_insert) | |
874 | { | |
875 | struct aarch64_debug_reg_state *state; | |
876 | ||
877 | /* The hardware breakpoint on AArch64 should always be 4-byte | |
878 | aligned. */ | |
879 | if (!aarch64_point_is_aligned (0 /* is_watchpoint */ , addr, len)) | |
880 | return -1; | |
881 | ||
882 | state = aarch64_get_debug_reg_state (); | |
883 | ||
884 | if (is_insert) | |
885 | return aarch64_dr_state_insert_one_point (state, type, addr, len); | |
886 | else | |
887 | return aarch64_dr_state_remove_one_point (state, type, addr, len); | |
888 | } | |
889 | ||
890 | /* This is essentially the same as aarch64_handle_breakpoint, apart | |
891 | from that it is an aligned watchpoint to be handled. */ | |
892 | ||
893 | static int | |
894 | aarch64_handle_aligned_watchpoint (enum target_point_type type, | |
895 | CORE_ADDR addr, int len, int is_insert) | |
896 | { | |
897 | struct aarch64_debug_reg_state *state; | |
898 | ||
899 | state = aarch64_get_debug_reg_state (); | |
900 | ||
901 | if (is_insert) | |
902 | return aarch64_dr_state_insert_one_point (state, type, addr, len); | |
903 | else | |
904 | return aarch64_dr_state_remove_one_point (state, type, addr, len); | |
905 | } | |
906 | ||
907 | /* Insert/remove unaligned watchpoint by calling | |
908 | aarch64_align_watchpoint repeatedly until the whole watched region, | |
909 | as represented by ADDR and LEN, has been properly aligned and ready | |
910 | to be written to one or more hardware watchpoint registers. | |
911 | IS_INSERT indicates whether this is an insertion or a deletion. | |
912 | Return 0 if succeed. */ | |
913 | ||
914 | static int | |
915 | aarch64_handle_unaligned_watchpoint (enum target_point_type type, | |
916 | CORE_ADDR addr, int len, int is_insert) | |
917 | { | |
918 | struct aarch64_debug_reg_state *state | |
919 | = aarch64_get_debug_reg_state (); | |
920 | ||
921 | while (len > 0) | |
922 | { | |
923 | CORE_ADDR aligned_addr; | |
924 | int aligned_len, ret; | |
925 | ||
926 | aarch64_align_watchpoint (addr, len, &aligned_addr, &aligned_len, | |
927 | &addr, &len); | |
928 | ||
929 | if (is_insert) | |
930 | ret = aarch64_dr_state_insert_one_point (state, type, aligned_addr, | |
931 | aligned_len); | |
932 | else | |
933 | ret = aarch64_dr_state_remove_one_point (state, type, aligned_addr, | |
934 | aligned_len); | |
935 | ||
936 | if (debug_hw_points) | |
937 | fprintf (stderr, | |
938 | "handle_unaligned_watchpoint: is_insert: %d\n" | |
939 | " aligned_addr: 0x%s, aligned_len: %d\n" | |
940 | " next_addr: 0x%s, next_len: %d\n", | |
941 | is_insert, paddress (aligned_addr), aligned_len, | |
942 | paddress (addr), len); | |
943 | ||
944 | if (ret != 0) | |
945 | return ret; | |
946 | } | |
947 | ||
948 | return 0; | |
949 | } | |
950 | ||
951 | static int | |
952 | aarch64_handle_watchpoint (enum target_point_type type, CORE_ADDR addr, | |
953 | int len, int is_insert) | |
954 | { | |
955 | if (aarch64_point_is_aligned (1 /* is_watchpoint */ , addr, len)) | |
956 | return aarch64_handle_aligned_watchpoint (type, addr, len, is_insert); | |
957 | else | |
958 | return aarch64_handle_unaligned_watchpoint (type, addr, len, is_insert); | |
959 | } | |
960 | ||
961 | /* Insert a hardware breakpoint/watchpoint. | |
962 | It actually only records the info of the to-be-inserted bp/wp; | |
963 | the actual insertion will happen when threads are resumed. | |
964 | ||
965 | Return 0 if succeed; | |
966 | Return 1 if TYPE is unsupported type; | |
967 | Return -1 if an error occurs. */ | |
968 | ||
969 | static int | |
970 | aarch64_insert_point (char type, CORE_ADDR addr, int len) | |
971 | { | |
972 | int ret; | |
973 | enum target_point_type targ_type; | |
974 | ||
975 | if (debug_hw_points) | |
976 | fprintf (stderr, "insert_point on entry (addr=0x%08lx, len=%d)\n", | |
977 | (unsigned long) addr, len); | |
978 | ||
979 | /* Determine the type from the packet. */ | |
980 | targ_type = Z_packet_to_point_type (type); | |
981 | if (targ_type == point_type_unsupported) | |
982 | return 1; | |
983 | ||
984 | if (targ_type != hw_execute) | |
985 | ret = | |
986 | aarch64_handle_watchpoint (targ_type, addr, len, 1 /* is_insert */); | |
987 | else | |
988 | ret = | |
989 | aarch64_handle_breakpoint (targ_type, addr, len, 1 /* is_insert */); | |
990 | ||
991 | if (debug_hw_points > 1) | |
992 | aarch64_show_debug_reg_state (aarch64_get_debug_reg_state (), | |
993 | "insert_point", addr, len, targ_type); | |
994 | ||
995 | return ret; | |
996 | } | |
997 | ||
998 | /* Remove a hardware breakpoint/watchpoint. | |
999 | It actually only records the info of the to-be-removed bp/wp, | |
1000 | the actual removal will be done when threads are resumed. | |
1001 | ||
1002 | Return 0 if succeed; | |
1003 | Return 1 if TYPE is an unsupported type; | |
1004 | Return -1 if an error occurs. */ | |
1005 | ||
1006 | static int | |
1007 | aarch64_remove_point (char type, CORE_ADDR addr, int len) | |
1008 | { | |
1009 | int ret; | |
1010 | enum target_point_type targ_type; | |
1011 | ||
1012 | if (debug_hw_points) | |
1013 | fprintf (stderr, "remove_point on entry (addr=0x%08lx, len=%d)\n", | |
1014 | (unsigned long) addr, len); | |
1015 | ||
1016 | /* Determine the type from the packet. */ | |
1017 | targ_type = Z_packet_to_point_type (type); | |
1018 | if (targ_type == point_type_unsupported) | |
1019 | return 1; | |
1020 | ||
1021 | /* Set up state pointers. */ | |
1022 | if (targ_type != hw_execute) | |
1023 | ret = | |
1024 | aarch64_handle_watchpoint (targ_type, addr, len, 0 /* is_insert */); | |
1025 | else | |
1026 | ret = | |
1027 | aarch64_handle_breakpoint (targ_type, addr, len, 0 /* is_insert */); | |
1028 | ||
1029 | if (debug_hw_points > 1) | |
1030 | aarch64_show_debug_reg_state (aarch64_get_debug_reg_state (), | |
1031 | "remove_point", addr, len, targ_type); | |
1032 | ||
1033 | return ret; | |
1034 | } | |
1035 | ||
1036 | /* Returns the address associated with the watchpoint that hit, if | |
1037 | any; returns 0 otherwise. */ | |
1038 | ||
1039 | static CORE_ADDR | |
1040 | aarch64_stopped_data_address (void) | |
1041 | { | |
1042 | siginfo_t siginfo; | |
1043 | int pid, i; | |
1044 | struct aarch64_debug_reg_state *state; | |
1045 | ||
1046 | pid = lwpid_of (get_thread_lwp (current_inferior)); | |
1047 | ||
1048 | /* Get the siginfo. */ | |
1049 | if (ptrace (PTRACE_GETSIGINFO, pid, NULL, &siginfo) != 0) | |
1050 | return (CORE_ADDR) 0; | |
1051 | ||
1052 | /* Need to be a hardware breakpoint/watchpoint trap. */ | |
1053 | if (siginfo.si_signo != SIGTRAP | |
1054 | || (siginfo.si_code & 0xffff) != 0x0004 /* TRAP_HWBKPT */) | |
1055 | return (CORE_ADDR) 0; | |
1056 | ||
1057 | /* Check if the address matches any watched address. */ | |
1058 | state = aarch64_get_debug_reg_state (); | |
1059 | for (i = aarch64_num_wp_regs - 1; i >= 0; --i) | |
1060 | { | |
1061 | const unsigned int len = aarch64_watchpoint_length (state->dr_ctrl_wp[i]); | |
1062 | const CORE_ADDR addr_trap = (CORE_ADDR) siginfo.si_addr; | |
1063 | const CORE_ADDR addr_watch = state->dr_addr_wp[i]; | |
1064 | if (state->dr_ref_count_wp[i] | |
1065 | && DR_CONTROL_ENABLED (state->dr_ctrl_wp[i]) | |
1066 | && addr_trap >= addr_watch | |
1067 | && addr_trap < addr_watch + len) | |
1068 | return addr_trap; | |
1069 | } | |
1070 | ||
1071 | return (CORE_ADDR) 0; | |
1072 | } | |
1073 | ||
1074 | /* Returns 1 if target was stopped due to a watchpoint hit, 0 | |
1075 | otherwise. */ | |
1076 | ||
1077 | static int | |
1078 | aarch64_stopped_by_watchpoint (void) | |
1079 | { | |
1080 | if (aarch64_stopped_data_address () != 0) | |
1081 | return 1; | |
1082 | else | |
1083 | return 0; | |
1084 | } | |
1085 | ||
1086 | /* Fetch the thread-local storage pointer for libthread_db. */ | |
1087 | ||
1088 | ps_err_e | |
55fac6e0 | 1089 | ps_get_thread_area (const struct ps_prochandle *ph, |
176eb98c MS |
1090 | lwpid_t lwpid, int idx, void **base) |
1091 | { | |
55fac6e0 MS |
1092 | struct iovec iovec; |
1093 | uint64_t reg; | |
1094 | ||
1095 | iovec.iov_base = ® | |
1096 | iovec.iov_len = sizeof (reg); | |
1097 | ||
1098 | if (ptrace (PTRACE_GETREGSET, lwpid, NT_ARM_TLS, &iovec) != 0) | |
176eb98c MS |
1099 | return PS_ERR; |
1100 | ||
1101 | /* IDX is the bias from the thread pointer to the beginning of the | |
1102 | thread descriptor. It has to be subtracted due to implementation | |
1103 | quirks in libthread_db. */ | |
55fac6e0 | 1104 | *base = (void *) (reg - idx); |
176eb98c MS |
1105 | |
1106 | return PS_OK; | |
1107 | } | |
1108 | ||
1109 | /* Called when a new process is created. */ | |
1110 | ||
1111 | static struct arch_process_info * | |
1112 | aarch64_linux_new_process (void) | |
1113 | { | |
1114 | struct arch_process_info *info = xcalloc (1, sizeof (*info)); | |
1115 | ||
1116 | aarch64_init_debug_reg_state (&info->debug_reg_state); | |
1117 | ||
1118 | return info; | |
1119 | } | |
1120 | ||
1121 | /* Called when a new thread is detected. */ | |
1122 | ||
1123 | static struct arch_lwp_info * | |
1124 | aarch64_linux_new_thread (void) | |
1125 | { | |
1126 | struct arch_lwp_info *info = xcalloc (1, sizeof (*info)); | |
1127 | ||
1128 | /* Mark that all the hardware breakpoint/watchpoint register pairs | |
1129 | for this thread need to be initialized (with data from | |
1130 | aarch_process_info.debug_reg_state). */ | |
1131 | DR_MARK_ALL_CHANGED (info->dr_changed_bp, aarch64_num_bp_regs); | |
1132 | DR_MARK_ALL_CHANGED (info->dr_changed_wp, aarch64_num_wp_regs); | |
1133 | ||
1134 | return info; | |
1135 | } | |
1136 | ||
1137 | /* Called when resuming a thread. | |
1138 | If the debug regs have changed, update the thread's copies. */ | |
1139 | ||
1140 | static void | |
1141 | aarch64_linux_prepare_to_resume (struct lwp_info *lwp) | |
1142 | { | |
1143 | ptid_t ptid = ptid_of (lwp); | |
1144 | struct arch_lwp_info *info = lwp->arch_private; | |
1145 | ||
1146 | if (DR_HAS_CHANGED (info->dr_changed_bp) | |
1147 | || DR_HAS_CHANGED (info->dr_changed_wp)) | |
1148 | { | |
1149 | int tid = ptid_get_lwp (ptid); | |
1150 | struct process_info *proc = find_process_pid (ptid_get_pid (ptid)); | |
1151 | struct aarch64_debug_reg_state *state | |
1152 | = &proc->private->arch_private->debug_reg_state; | |
1153 | ||
1154 | if (debug_hw_points) | |
1155 | fprintf (stderr, "prepare_to_resume thread %ld\n", lwpid_of (lwp)); | |
1156 | ||
1157 | /* Watchpoints. */ | |
1158 | if (DR_HAS_CHANGED (info->dr_changed_wp)) | |
1159 | { | |
1160 | aarch64_linux_set_debug_regs (state, tid, 1); | |
1161 | DR_CLEAR_CHANGED (info->dr_changed_wp); | |
1162 | } | |
1163 | ||
1164 | /* Breakpoints. */ | |
1165 | if (DR_HAS_CHANGED (info->dr_changed_bp)) | |
1166 | { | |
1167 | aarch64_linux_set_debug_regs (state, tid, 0); | |
1168 | DR_CLEAR_CHANGED (info->dr_changed_bp); | |
1169 | } | |
1170 | } | |
1171 | } | |
1172 | ||
1173 | /* ptrace hardware breakpoint resource info is formatted as follows: | |
1174 | ||
1175 | 31 24 16 8 0 | |
1176 | +---------------+--------------+---------------+---------------+ | |
1177 | | RESERVED | RESERVED | DEBUG_ARCH | NUM_SLOTS | | |
1178 | +---------------+--------------+---------------+---------------+ */ | |
1179 | ||
1180 | #define AARCH64_DEBUG_NUM_SLOTS(x) ((x) & 0xff) | |
1181 | #define AARCH64_DEBUG_ARCH(x) (((x) >> 8) & 0xff) | |
1182 | #define AARCH64_DEBUG_ARCH_V8 0x6 | |
1183 | ||
1184 | static void | |
1185 | aarch64_arch_setup (void) | |
1186 | { | |
1187 | int pid; | |
1188 | struct iovec iov; | |
1189 | struct user_hwdebug_state dreg_state; | |
1190 | ||
1191 | init_registers_aarch64 (); | |
1192 | ||
1193 | pid = lwpid_of (get_thread_lwp (current_inferior)); | |
1194 | iov.iov_base = &dreg_state; | |
1195 | iov.iov_len = sizeof (dreg_state); | |
1196 | ||
1197 | /* Get hardware watchpoint register info. */ | |
1198 | if (ptrace (PTRACE_GETREGSET, pid, NT_ARM_HW_WATCH, &iov) == 0 | |
1199 | && AARCH64_DEBUG_ARCH (dreg_state.dbg_info) == AARCH64_DEBUG_ARCH_V8) | |
1200 | { | |
1201 | aarch64_num_wp_regs = AARCH64_DEBUG_NUM_SLOTS (dreg_state.dbg_info); | |
148de6bb MS |
1202 | if (aarch64_num_wp_regs > AARCH64_HWP_MAX_NUM) |
1203 | { | |
1204 | warning ("Unexpected number of hardware watchpoint registers reported" | |
1205 | " by ptrace, got %d, expected %d.", | |
1206 | aarch64_num_wp_regs, AARCH64_HWP_MAX_NUM); | |
1207 | aarch64_num_wp_regs = AARCH64_HWP_MAX_NUM; | |
1208 | } | |
176eb98c MS |
1209 | } |
1210 | else | |
1211 | { | |
1212 | warning ("Unable to determine the number of hardware watchpoints" | |
1213 | " available."); | |
1214 | aarch64_num_wp_regs = 0; | |
1215 | } | |
1216 | ||
1217 | /* Get hardware breakpoint register info. */ | |
1218 | if (ptrace (PTRACE_GETREGSET, pid, NT_ARM_HW_BREAK, &iov) == 0 | |
1219 | && AARCH64_DEBUG_ARCH (dreg_state.dbg_info) == AARCH64_DEBUG_ARCH_V8) | |
1220 | { | |
1221 | aarch64_num_bp_regs = AARCH64_DEBUG_NUM_SLOTS (dreg_state.dbg_info); | |
1222 | if (aarch64_num_bp_regs > AARCH64_HBP_MAX_NUM) | |
148de6bb MS |
1223 | { |
1224 | warning ("Unexpected number of hardware breakpoint registers reported" | |
1225 | " by ptrace, got %d, expected %d.", | |
1226 | aarch64_num_bp_regs, AARCH64_HBP_MAX_NUM); | |
1227 | aarch64_num_bp_regs = AARCH64_HBP_MAX_NUM; | |
1228 | } | |
176eb98c MS |
1229 | } |
1230 | else | |
1231 | { | |
1232 | warning ("Unable to determine the number of hardware breakpoints" | |
1233 | " available."); | |
1234 | aarch64_num_bp_regs = 0; | |
1235 | } | |
1236 | } | |
1237 | ||
1238 | struct regset_info target_regsets[] = | |
1239 | { | |
1240 | { PTRACE_GETREGSET, PTRACE_SETREGSET, NT_PRSTATUS, | |
1241 | sizeof (struct user_pt_regs), GENERAL_REGS, | |
1242 | aarch64_fill_gregset, aarch64_store_gregset }, | |
1243 | { PTRACE_GETREGSET, PTRACE_SETREGSET, NT_FPREGSET, | |
1244 | sizeof (struct user_fpsimd_state), FP_REGS, | |
1245 | aarch64_fill_fpregset, aarch64_store_fpregset | |
1246 | }, | |
1247 | { 0, 0, 0, -1, -1, NULL, NULL } | |
1248 | }; | |
1249 | ||
1250 | struct linux_target_ops the_low_target = | |
1251 | { | |
1252 | aarch64_arch_setup, | |
1253 | AARCH64_NUM_REGS, | |
1254 | aarch64_regmap, | |
1255 | NULL, | |
1256 | aarch64_cannot_fetch_register, | |
1257 | aarch64_cannot_store_register, | |
1258 | NULL, | |
1259 | aarch64_get_pc, | |
1260 | aarch64_set_pc, | |
1261 | (const unsigned char *) &aarch64_breakpoint, | |
1262 | aarch64_breakpoint_len, | |
1263 | NULL, | |
1264 | 0, | |
1265 | aarch64_breakpoint_at, | |
1266 | aarch64_insert_point, | |
1267 | aarch64_remove_point, | |
1268 | aarch64_stopped_by_watchpoint, | |
1269 | aarch64_stopped_data_address, | |
1270 | NULL, | |
1271 | NULL, | |
1272 | NULL, | |
1273 | aarch64_linux_new_process, | |
1274 | aarch64_linux_new_thread, | |
1275 | aarch64_linux_prepare_to_resume, | |
1276 | }; |