xref: /netbsd-src/external/gpl3/gdb.old/dist/gdbserver/linux-s390-ipa.cc (revision d16b7486a53dcb8072b60ec6fcb4373a2d0c27b7)
1 /* GNU/Linux S/390 specific low level interface, for the in-process
2    agent library for GDB.
3 
4    Copyright (C) 2016-2020 Free Software Foundation, Inc.
5 
6    This file is part of GDB.
7 
8    This program is free software; you can redistribute it and/or modify
9    it under the terms of the GNU General Public License as published by
10    the Free Software Foundation; either version 3 of the License, or
11    (at your option) any later version.
12 
13    This program is distributed in the hope that it will be useful,
14    but WITHOUT ANY WARRANTY; without even the implied warranty of
15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16    GNU General Public License for more details.
17 
18    You should have received a copy of the GNU General Public License
19    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
20 
21 #include "server.h"
22 #include <sys/mman.h>
23 #include "tracepoint.h"
24 #include "linux-s390-tdesc.h"
25 #include <elf.h>
26 #ifdef HAVE_GETAUXVAL
27 #include <sys/auxv.h>
28 #endif
29 
30 #define FT_FPR(x) (0x000 + (x) * 0x10)
31 #define FT_VR(x) (0x000 + (x) * 0x10)
32 #define FT_VR_L(x) (0x008 + (x) * 0x10)
33 #define FT_GPR(x) (0x200 + (x) * 8)
34 #define FT_GPR_U(x) (0x200 + (x) * 8)
35 #define FT_GPR_L(x) (0x204 + (x) * 8)
36 #define FT_GPR(x) (0x200 + (x) * 8)
37 #define FT_ACR(x) (0x280 + (x) * 4)
38 #define FT_PSWM 0x2c0
39 #define FT_PSWM_U 0x2c0
40 #define FT_PSWA 0x2c8
41 #define FT_PSWA_L 0x2cc
42 #define FT_FPC 0x2d0
43 
44 /* Mappings between registers collected by the jump pad and GDB's register
45    array layout used by regcache.
46 
47    See linux-s390-low.c (s390_install_fast_tracepoint_jump_pad) for more
48    details.  */
49 
50 #ifndef __s390x__
51 
52 /* Used for s390-linux32, s390-linux32v1, s390-linux32v2.  */
53 
54 static const int s390_linux32_ft_collect_regmap[] = {
55   /* 32-bit PSWA and PSWM.  */
56   FT_PSWM_U, FT_PSWA_L,
57   /* 32-bit GPRs (mapped to lower halves of 64-bit slots).  */
58   FT_GPR_L (0), FT_GPR_L (1), FT_GPR_L (2), FT_GPR_L (3),
59   FT_GPR_L (4), FT_GPR_L (5), FT_GPR_L (6), FT_GPR_L (7),
60   FT_GPR_L (8), FT_GPR_L (9), FT_GPR_L (10), FT_GPR_L (11),
61   FT_GPR_L (12), FT_GPR_L (13), FT_GPR_L (14), FT_GPR_L (15),
62   /* ACRs */
63   FT_ACR (0), FT_ACR (1), FT_ACR (2), FT_ACR (3),
64   FT_ACR (4), FT_ACR (5), FT_ACR (6), FT_ACR (7),
65   FT_ACR (8), FT_ACR (9), FT_ACR (10), FT_ACR (11),
66   FT_ACR (12), FT_ACR (13), FT_ACR (14), FT_ACR (15),
67   /* FPRs (mapped to upper halves of 128-bit VR slots).  */
68   FT_FPR (0), FT_FPR (1), FT_FPR (2), FT_FPR (3),
69   FT_FPR (4), FT_FPR (5), FT_FPR (6), FT_FPR (7),
70   FT_FPR (8), FT_FPR (9), FT_FPR (10), FT_FPR (11),
71   FT_FPR (12), FT_FPR (13), FT_FPR (14), FT_FPR (15),
72   /* orig_r2, last_break, system_call */
73   -1, -1, -1,
74 };
75 
76 /* Used for s390-linux64, s390-linux64v1, s390-linux64v2, s390-vx-linux64.  */
77 
78 static const int s390_linux64_ft_collect_regmap[] = {
79   /* 32-bit PSWA and PSWM.  */
80   FT_PSWM_U, FT_PSWA_L,
81   /* 32-bit halves of 64-bit GPRs.  */
82   FT_GPR_U (0), FT_GPR_L (0),
83   FT_GPR_U (1), FT_GPR_L (1),
84   FT_GPR_U (2), FT_GPR_L (2),
85   FT_GPR_U (3), FT_GPR_L (3),
86   FT_GPR_U (4), FT_GPR_L (4),
87   FT_GPR_U (5), FT_GPR_L (5),
88   FT_GPR_U (6), FT_GPR_L (6),
89   FT_GPR_U (7), FT_GPR_L (7),
90   FT_GPR_U (8), FT_GPR_L (8),
91   FT_GPR_U (9), FT_GPR_L (9),
92   FT_GPR_U (10), FT_GPR_L (10),
93   FT_GPR_U (11), FT_GPR_L (11),
94   FT_GPR_U (12), FT_GPR_L (12),
95   FT_GPR_U (13), FT_GPR_L (13),
96   FT_GPR_U (14), FT_GPR_L (14),
97   FT_GPR_U (15), FT_GPR_L (15),
98   /* ACRs */
99   FT_ACR (0), FT_ACR (1), FT_ACR (2), FT_ACR (3),
100   FT_ACR (4), FT_ACR (5), FT_ACR (6), FT_ACR (7),
101   FT_ACR (8), FT_ACR (9), FT_ACR (10), FT_ACR (11),
102   FT_ACR (12), FT_ACR (13), FT_ACR (14), FT_ACR (15),
103   /* FPRs (mapped to upper halves of 128-bit VR slots).  */
104   FT_FPR (0), FT_FPR (1), FT_FPR (2), FT_FPR (3),
105   FT_FPR (4), FT_FPR (5), FT_FPR (6), FT_FPR (7),
106   FT_FPR (8), FT_FPR (9), FT_FPR (10), FT_FPR (11),
107   FT_FPR (12), FT_FPR (13), FT_FPR (14), FT_FPR (15),
108   /* orig_r2, last_break, system_call */
109   -1, -1, -1,
110   /* Lower halves of 128-bit VRs. */
111   FT_VR_L (0), FT_VR_L (1), FT_VR_L (2), FT_VR_L (3),
112   FT_VR_L (4), FT_VR_L (5), FT_VR_L (6), FT_VR_L (7),
113   FT_VR_L (8), FT_VR_L (9), FT_VR_L (10), FT_VR_L (11),
114   FT_VR_L (12), FT_VR_L (13), FT_VR_L (14), FT_VR_L (15),
115   /* And the next 16 VRs.  */
116   FT_VR (16), FT_VR (17), FT_VR (18), FT_VR (19),
117   FT_VR (20), FT_VR (21), FT_VR (22), FT_VR (23),
118   FT_VR (24), FT_VR (25), FT_VR (26), FT_VR (27),
119   FT_VR (28), FT_VR (29), FT_VR (30), FT_VR (31),
120 };
121 
122 /* Used for s390-te-linux64, s390-tevx-linux64, and s390-gs-linux64.  */
123 
124 static const int s390_te_linux64_ft_collect_regmap[] = {
125   /* 32-bit PSWA and PSWM.  */
126   FT_PSWM_U, FT_PSWA_L,
127   /* 32-bit halves of 64-bit GPRs.  */
128   FT_GPR_U (0), FT_GPR_L (0),
129   FT_GPR_U (1), FT_GPR_L (1),
130   FT_GPR_U (2), FT_GPR_L (2),
131   FT_GPR_U (3), FT_GPR_L (3),
132   FT_GPR_U (4), FT_GPR_L (4),
133   FT_GPR_U (5), FT_GPR_L (5),
134   FT_GPR_U (6), FT_GPR_L (6),
135   FT_GPR_U (7), FT_GPR_L (7),
136   FT_GPR_U (8), FT_GPR_L (8),
137   FT_GPR_U (9), FT_GPR_L (9),
138   FT_GPR_U (10), FT_GPR_L (10),
139   FT_GPR_U (11), FT_GPR_L (11),
140   FT_GPR_U (12), FT_GPR_L (12),
141   FT_GPR_U (13), FT_GPR_L (13),
142   FT_GPR_U (14), FT_GPR_L (14),
143   FT_GPR_U (15), FT_GPR_L (15),
144   /* ACRs */
145   FT_ACR (0), FT_ACR (1), FT_ACR (2), FT_ACR (3),
146   FT_ACR (4), FT_ACR (5), FT_ACR (6), FT_ACR (7),
147   FT_ACR (8), FT_ACR (9), FT_ACR (10), FT_ACR (11),
148   FT_ACR (12), FT_ACR (13), FT_ACR (14), FT_ACR (15),
149   /* FPRs (mapped to upper halves of 128-bit VR slots).  */
150   FT_FPR (0), FT_FPR (1), FT_FPR (2), FT_FPR (3),
151   FT_FPR (4), FT_FPR (5), FT_FPR (6), FT_FPR (7),
152   FT_FPR (8), FT_FPR (9), FT_FPR (10), FT_FPR (11),
153   FT_FPR (12), FT_FPR (13), FT_FPR (14), FT_FPR (15),
154   /* orig_r2, last_break, system_call */
155   -1, -1, -1,
156   /* TDB */
157   -1, -1, -1, -1,
158   -1, -1, -1, -1,
159   -1, -1, -1, -1,
160   -1, -1, -1, -1,
161   -1, -1, -1, -1,
162   /* Lower halves of 128-bit VRs. */
163   FT_VR_L (0), FT_VR_L (1), FT_VR_L (2), FT_VR_L (3),
164   FT_VR_L (4), FT_VR_L (5), FT_VR_L (6), FT_VR_L (7),
165   FT_VR_L (8), FT_VR_L (9), FT_VR_L (10), FT_VR_L (11),
166   FT_VR_L (12), FT_VR_L (13), FT_VR_L (14), FT_VR_L (15),
167   /* And the next 16 VRs.  */
168   FT_VR (16), FT_VR (17), FT_VR (18), FT_VR (19),
169   FT_VR (20), FT_VR (21), FT_VR (22), FT_VR (23),
170   FT_VR (24), FT_VR (25), FT_VR (26), FT_VR (27),
171   FT_VR (28), FT_VR (29), FT_VR (30), FT_VR (31),
172 };
173 
174 #else /* __s390x__ */
175 
176 /* Used for s390x-linux64, s390x-linux64v1, s390x-linux64v2, s390x-vx-linux64.  */
177 
178 static const int s390x_ft_collect_regmap[] = {
179   /* 64-bit PSWA and PSWM.  */
180   FT_PSWM, FT_PSWA,
181   /* 64-bit GPRs.  */
182   FT_GPR (0), FT_GPR (1), FT_GPR (2), FT_GPR (3),
183   FT_GPR (4), FT_GPR (5), FT_GPR (6), FT_GPR (7),
184   FT_GPR (8), FT_GPR (9), FT_GPR (10), FT_GPR (11),
185   FT_GPR (12), FT_GPR (13), FT_GPR (14), FT_GPR (15),
186   /* ACRs */
187   FT_ACR (0), FT_ACR (1), FT_ACR (2), FT_ACR (3),
188   FT_ACR (4), FT_ACR (5), FT_ACR (6), FT_ACR (7),
189   FT_ACR (8), FT_ACR (9), FT_ACR (10), FT_ACR (11),
190   FT_ACR (12), FT_ACR (13), FT_ACR (14), FT_ACR (15),
191   /* FPRs (mapped to upper halves of 128-bit VR slots).  */
192   FT_FPR (0), FT_FPR (1), FT_FPR (2), FT_FPR (3),
193   FT_FPR (4), FT_FPR (5), FT_FPR (6), FT_FPR (7),
194   FT_FPR (8), FT_FPR (9), FT_FPR (10), FT_FPR (11),
195   FT_FPR (12), FT_FPR (13), FT_FPR (14), FT_FPR (15),
196   /* orig_r2, last_break, system_call */
197   -1, -1, -1,
198   /* Lower halves of 128-bit VRs. */
199   FT_VR_L (0), FT_VR_L (1), FT_VR_L (2), FT_VR_L (3),
200   FT_VR_L (4), FT_VR_L (5), FT_VR_L (6), FT_VR_L (7),
201   FT_VR_L (8), FT_VR_L (9), FT_VR_L (10), FT_VR_L (11),
202   FT_VR_L (12), FT_VR_L (13), FT_VR_L (14), FT_VR_L (15),
203   /* And the next 16 VRs.  */
204   FT_VR (16), FT_VR (17), FT_VR (18), FT_VR (19),
205   FT_VR (20), FT_VR (21), FT_VR (22), FT_VR (23),
206   FT_VR (24), FT_VR (25), FT_VR (26), FT_VR (27),
207   FT_VR (28), FT_VR (29), FT_VR (30), FT_VR (31),
208 };
209 
210 /* Used for s390x-te-linux64, s390x-tevx-linux64, and
211    s390x-gs-linux64.  */
212 
213 static const int s390x_te_ft_collect_regmap[] = {
214   /* 64-bit PSWA and PSWM.  */
215   FT_PSWM, FT_PSWA,
216   /* 64-bit GPRs.  */
217   FT_GPR (0), FT_GPR (1), FT_GPR (2), FT_GPR (3),
218   FT_GPR (4), FT_GPR (5), FT_GPR (6), FT_GPR (7),
219   FT_GPR (8), FT_GPR (9), FT_GPR (10), FT_GPR (11),
220   FT_GPR (12), FT_GPR (13), FT_GPR (14), FT_GPR (15),
221   /* ACRs */
222   FT_ACR (0), FT_ACR (1), FT_ACR (2), FT_ACR (3),
223   FT_ACR (4), FT_ACR (5), FT_ACR (6), FT_ACR (7),
224   FT_ACR (8), FT_ACR (9), FT_ACR (10), FT_ACR (11),
225   FT_ACR (12), FT_ACR (13), FT_ACR (14), FT_ACR (15),
226   /* FPRs (mapped to upper halves of 128-bit VR slots).  */
227   FT_FPR (0), FT_FPR (1), FT_FPR (2), FT_FPR (3),
228   FT_FPR (4), FT_FPR (5), FT_FPR (6), FT_FPR (7),
229   FT_FPR (8), FT_FPR (9), FT_FPR (10), FT_FPR (11),
230   FT_FPR (12), FT_FPR (13), FT_FPR (14), FT_FPR (15),
231   /* orig_r2, last_break, system_call */
232   -1, -1, -1,
233   /* TDB */
234   -1, -1, -1, -1,
235   -1, -1, -1, -1,
236   -1, -1, -1, -1,
237   -1, -1, -1, -1,
238   -1, -1, -1, -1,
239   /* Lower halves of 128-bit VRs. */
240   FT_VR_L (0), FT_VR_L (1), FT_VR_L (2), FT_VR_L (3),
241   FT_VR_L (4), FT_VR_L (5), FT_VR_L (6), FT_VR_L (7),
242   FT_VR_L (8), FT_VR_L (9), FT_VR_L (10), FT_VR_L (11),
243   FT_VR_L (12), FT_VR_L (13), FT_VR_L (14), FT_VR_L (15),
244   /* And the next 16 VRs.  */
245   FT_VR (16), FT_VR (17), FT_VR (18), FT_VR (19),
246   FT_VR (20), FT_VR (21), FT_VR (22), FT_VR (23),
247   FT_VR (24), FT_VR (25), FT_VR (26), FT_VR (27),
248   FT_VR (28), FT_VR (29), FT_VR (30), FT_VR (31),
249 };
250 
251 #endif
252 
253 /* Initialized by get_ipa_tdesc according to the tdesc in use.  */
254 
255 static const int *s390_regmap;
256 static int s390_regnum;
257 
258 /* Fill in REGCACHE with registers saved by the jump pad in BUF.  */
259 
260 void
261 supply_fast_tracepoint_registers (struct regcache *regcache,
262 				  const unsigned char *buf)
263 {
264   int i;
265   for (i = 0; i < s390_regnum; i++)
266     if (s390_regmap[i] != -1)
267       supply_register (regcache, i, ((char *) buf) + s390_regmap[i]);
268 }
269 
270 ULONGEST
271 get_raw_reg (const unsigned char *raw_regs, int regnum)
272 {
273   int offset;
274   if (regnum >= s390_regnum)
275     return 0;
276   offset = s390_regmap[regnum];
277   if (offset == -1)
278     return 0;
279 
280   /* The regnums are variable, better to figure out size by FT offset.  */
281 
282   /* 64-bit ones.  */
283   if (offset < FT_VR(16)
284 #ifdef __s390x__
285       || (offset >= FT_GPR(0) && offset < FT_ACR(0))
286       || offset == FT_PSWM
287       || offset == FT_PSWA
288 #endif
289      )
290     return *(uint64_t *) (raw_regs + offset);
291 
292   if (offset >= FT_ACR(0 && offset < FT_PSWM)
293       || offset == FT_FPC
294 #ifndef __s390x__
295       || (offset >= FT_GPR(0) && offset < FT_ACR(0))
296       || offset == FT_PSWM_U
297       || offset == FT_PSWA_L
298 #endif
299      )
300     return *(uint32_t *) (raw_regs + offset);
301 
302   /* This leaves 128-bit VX.  No way to return them.  */
303   return 0;
304 }
305 
306 /* Return target_desc to use for IPA, given the tdesc index passed by
307    gdbserver.  For s390, it also sets s390_regmap and s390_regnum.  */
308 
309 const struct target_desc *
310 get_ipa_tdesc (int idx)
311 {
312 #define SET_REGMAP(regmap, skip_last) \
313 	do { \
314 	  s390_regmap = regmap; \
315 	  s390_regnum = (sizeof regmap / sizeof regmap[0]) - skip_last; \
316 	} while(0)
317   switch (idx)
318     {
319 #ifdef __s390x__
320     case S390_TDESC_64:
321       /* Subtract number of VX regs.  */
322       SET_REGMAP(s390x_ft_collect_regmap, 32);
323       return tdesc_s390x_linux64;
324     case S390_TDESC_64V1:
325       SET_REGMAP(s390x_ft_collect_regmap, 32);
326       return tdesc_s390x_linux64v1;
327     case S390_TDESC_64V2:
328       SET_REGMAP(s390x_ft_collect_regmap, 32);
329       return tdesc_s390x_linux64v2;
330     case S390_TDESC_TE:
331       SET_REGMAP(s390x_te_ft_collect_regmap, 32);
332       return tdesc_s390x_te_linux64;
333     case S390_TDESC_VX:
334       SET_REGMAP(s390x_ft_collect_regmap, 0);
335       return tdesc_s390x_vx_linux64;
336     case S390_TDESC_TEVX:
337       SET_REGMAP(s390x_te_ft_collect_regmap, 0);
338       return tdesc_s390x_tevx_linux64;
339     case S390_TDESC_GS:
340       SET_REGMAP(s390x_te_ft_collect_regmap, 0);
341       return tdesc_s390x_gs_linux64;
342 #else
343     case S390_TDESC_32:
344       SET_REGMAP(s390_linux32_ft_collect_regmap, 0);
345       return tdesc_s390_linux32;
346     case S390_TDESC_32V1:
347       SET_REGMAP(s390_linux32_ft_collect_regmap, 0);
348       return tdesc_s390_linux32v1;
349     case S390_TDESC_32V2:
350       SET_REGMAP(s390_linux32_ft_collect_regmap, 0);
351       return tdesc_s390_linux32v2;
352     case S390_TDESC_64:
353       SET_REGMAP(s390_linux64_ft_collect_regmap, 32);
354       return tdesc_s390_linux64;
355     case S390_TDESC_64V1:
356       SET_REGMAP(s390_linux64_ft_collect_regmap, 32);
357       return tdesc_s390_linux64v1;
358     case S390_TDESC_64V2:
359       SET_REGMAP(s390_linux64_ft_collect_regmap, 32);
360       return tdesc_s390_linux64v2;
361     case S390_TDESC_TE:
362       SET_REGMAP(s390_te_linux64_ft_collect_regmap, 32);
363       return tdesc_s390_te_linux64;
364     case S390_TDESC_VX:
365       SET_REGMAP(s390_linux64_ft_collect_regmap, 0);
366       return tdesc_s390_vx_linux64;
367     case S390_TDESC_TEVX:
368       SET_REGMAP(s390_te_linux64_ft_collect_regmap, 0);
369       return tdesc_s390_tevx_linux64;
370     case S390_TDESC_GS:
371       SET_REGMAP(s390_te_linux64_ft_collect_regmap, 0);
372       return tdesc_s390_gs_linux64;
373 #endif
374     default:
375       internal_error (__FILE__, __LINE__,
376 		      "unknown ipa tdesc index: %d", idx);
377 #ifdef __s390x__
378       return tdesc_s390x_linux64;
379 #else
380       return tdesc_s390_linux32;
381 #endif
382     }
383 }
384 
385 /* Allocate buffer for the jump pads.  On 31-bit, JG reaches everywhere,
386    so just allocate normally.  On 64-bit, we have +/-4GiB of reach, and
387    the executable is usually mapped at 0x80000000 - aim for somewhere
388    below it.  */
389 
390 void *
391 alloc_jump_pad_buffer (size_t size)
392 {
393 #ifdef __s390x__
394   uintptr_t addr;
395   uintptr_t exec_base = getauxval (AT_PHDR);
396   int pagesize;
397   void *res;
398 
399   if (exec_base == 0)
400     exec_base = 0x80000000;
401 
402   pagesize = sysconf (_SC_PAGE_SIZE);
403   if (pagesize == -1)
404     perror_with_name ("sysconf");
405 
406   addr = exec_base - size;
407 
408   /* size should already be page-aligned, but this can't hurt.  */
409   addr &= ~(pagesize - 1);
410 
411   /* Search for a free area.  If we hit 0, we're out of luck.  */
412   for (; addr; addr -= pagesize)
413     {
414       /* No MAP_FIXED - we don't want to zap someone's mapping.  */
415       res = mmap ((void *) addr, size,
416 		  PROT_READ | PROT_WRITE | PROT_EXEC,
417 		  MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
418 
419       /* If we got what we wanted, return.  */
420       if ((uintptr_t) res == addr)
421 	return res;
422 
423       /* If we got a mapping, but at a wrong address, undo it.  */
424       if (res != MAP_FAILED)
425 	munmap (res, size);
426     }
427 
428   return NULL;
429 #else
430   void *res = mmap (NULL, size, PROT_READ | PROT_WRITE | PROT_EXEC,
431 		    MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
432 
433   if (res == MAP_FAILED)
434     return NULL;
435 
436   return res;
437 #endif
438 }
439 
440 void
441 initialize_low_tracepoint (void)
442 {
443 #ifdef __s390x__
444   init_registers_s390x_linux64 ();
445   init_registers_s390x_linux64v1 ();
446   init_registers_s390x_linux64v2 ();
447   init_registers_s390x_te_linux64 ();
448   init_registers_s390x_vx_linux64 ();
449   init_registers_s390x_tevx_linux64 ();
450   init_registers_s390x_gs_linux64 ();
451 #else
452   init_registers_s390_linux32 ();
453   init_registers_s390_linux32v1 ();
454   init_registers_s390_linux32v2 ();
455   init_registers_s390_linux64 ();
456   init_registers_s390_linux64v1 ();
457   init_registers_s390_linux64v2 ();
458   init_registers_s390_te_linux64 ();
459   init_registers_s390_vx_linux64 ();
460   init_registers_s390_tevx_linux64 ();
461   init_registers_s390_gs_linux64 ();
462 #endif
463 }
464