1 /* Native-dependent code for SPARC. 2 3 Copyright 2003, 2004 Free Software Foundation, Inc. 4 5 This file is part of GDB. 6 7 This program is free software; you can redistribute it and/or modify 8 it under the terms of the GNU General Public License as published by 9 the Free Software Foundation; either version 2 of the License, or 10 (at your option) any later version. 11 12 This program is distributed in the hope that it will be useful, 13 but WITHOUT ANY WARRANTY; without even the implied warranty of 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 GNU General Public License for more details. 16 17 You should have received a copy of the GNU General Public License 18 along with this program; if not, write to the Free Software 19 Foundation, Inc., 59 Temple Place - Suite 330, 20 Boston, MA 02111-1307, USA. */ 21 22 #include "defs.h" 23 #include "inferior.h" 24 #include "regcache.h" 25 #include "target.h" 26 27 #include "gdb_assert.h" 28 #include <signal.h> 29 #include "gdb_string.h" 30 #include <sys/ptrace.h> 31 #include "gdb_wait.h" 32 #ifdef HAVE_MACHINE_REG_H 33 #include <machine/reg.h> 34 #endif 35 36 #include "sparc-tdep.h" 37 #include "sparc-nat.h" 38 #include "inf-ptrace.h" 39 40 /* With some trickery we can use the code in this file for most (if 41 not all) ptrace(2) based SPARC systems, which includes SunOS 4, 42 GNU/Linux and the various SPARC BSD's. 43 44 First, we need a data structure for use with ptrace(2). SunOS has 45 `struct regs' and `struct fp_status' in <machine/reg.h>. BSD's 46 have `struct reg' and `struct fpreg' in <machine/reg.h>. GNU/Linux 47 has the same structures as SunOS 4, but they're in <asm/reg.h>, 48 which is a kernel header. As a general rule we avoid including 49 GNU/Linux kernel headers. Fortunately GNU/Linux has a `gregset_t' 50 and a `fpregset_t' that are equivalent to `struct regs' and `struct 51 fp_status' in <sys/ucontext.h>, which is automatically included by 52 <signal.h>. Settling on using the `gregset_t' and `fpregset_t' 53 typedefs, providing them for the other systems, therefore solves 54 the puzzle. */ 55 56 #ifdef HAVE_MACHINE_REG_H 57 #ifdef HAVE_STRUCT_REG 58 typedef struct reg gregset_t; 59 typedef struct fpreg fpregset_t; 60 #else 61 typedef struct regs gregset_t; 62 typedef struct fp_status fpregset_t; 63 #endif 64 #endif 65 66 /* Second, we need to remap the BSD ptrace(2) requests to their SunOS 67 equivalents. GNU/Linux already follows SunOS here. */ 68 69 #ifndef PTRACE_GETREGS 70 #define PTRACE_GETREGS PT_GETREGS 71 #endif 72 73 #ifndef PTRACE_SETREGS 74 #define PTRACE_SETREGS PT_SETREGS 75 #endif 76 77 #ifndef PTRACE_GETFPREGS 78 #define PTRACE_GETFPREGS PT_GETFPREGS 79 #endif 80 81 #ifndef PTRACE_SETFPREGS 82 #define PTRACE_SETFPREGS PT_SETFPREGS 83 #endif 84 85 /* Register set description. */ 86 const struct sparc_gregset *sparc_gregset; 87 void (*sparc_supply_gregset) (const struct sparc_gregset *, 88 struct regcache *, int , const void *); 89 void (*sparc_collect_gregset) (const struct sparc_gregset *, 90 const struct regcache *, int, void *); 91 void (*sparc_supply_fpregset) (struct regcache *, int , const void *); 92 void (*sparc_collect_fpregset) (const struct regcache *, int , void *); 93 int (*sparc_gregset_supplies_p) (int); 94 int (*sparc_fpregset_supplies_p) (int); 95 96 /* Determine whether `gregset_t' contains register REGNUM. */ 97 98 int 99 sparc32_gregset_supplies_p (int regnum) 100 { 101 /* Integer registers. */ 102 if ((regnum >= SPARC_G1_REGNUM && regnum <= SPARC_G7_REGNUM) 103 || (regnum >= SPARC_O0_REGNUM && regnum <= SPARC_O7_REGNUM) 104 || (regnum >= SPARC_L0_REGNUM && regnum <= SPARC_L7_REGNUM) 105 || (regnum >= SPARC_I0_REGNUM && regnum <= SPARC_I7_REGNUM)) 106 return 1; 107 108 /* Control registers. */ 109 if (regnum == SPARC32_PC_REGNUM 110 || regnum == SPARC32_NPC_REGNUM 111 || regnum == SPARC32_PSR_REGNUM 112 || regnum == SPARC32_Y_REGNUM) 113 return 1; 114 115 return 0; 116 } 117 118 /* Determine whether `fpregset_t' contains register REGNUM. */ 119 120 int 121 sparc32_fpregset_supplies_p (int regnum) 122 { 123 /* Floating-point registers. */ 124 if (regnum >= SPARC_F0_REGNUM && regnum <= SPARC_F31_REGNUM) 125 return 1; 126 127 /* Control registers. */ 128 if (regnum == SPARC32_FSR_REGNUM) 129 return 1; 130 131 return 0; 132 } 133 134 /* Fetch register REGNUM from the inferior. If REGNUM is -1, do this 135 for all registers (including the floating-point registers). */ 136 137 void 138 fetch_inferior_registers (int regnum) 139 { 140 struct regcache *regcache = current_regcache; 141 int pid; 142 143 /* NOTE: cagney/2002-12-03: This code assumes that the currently 144 selected light weight processes' registers can be written 145 directly into the selected thread's register cache. This works 146 fine when given an 1:1 LWP:thread model (such as found on 147 GNU/Linux) but will, likely, have problems when used on an N:1 148 (userland threads) or N:M (userland multiple LWP) model. In the 149 case of the latter two, the LWP's registers do not necessarily 150 belong to the selected thread (the LWP could be in the middle of 151 executing the thread switch code). 152 153 These functions should instead be paramaterized with an explicit 154 object (struct regcache, struct thread_info?) into which the LWPs 155 registers can be written. */ 156 pid = TIDGET (inferior_ptid); 157 if (pid == 0) 158 pid = PIDGET (inferior_ptid); 159 160 if (regnum == SPARC_G0_REGNUM) 161 { 162 regcache_raw_supply (regcache, SPARC_G0_REGNUM, NULL); 163 return; 164 } 165 166 if (regnum == -1 || sparc_gregset_supplies_p (regnum)) 167 { 168 gregset_t regs; 169 170 if (ptrace (PTRACE_GETREGS, pid, (PTRACE_TYPE_ARG3) ®s, 0) == -1) 171 perror_with_name ("Couldn't get registers"); 172 173 sparc_supply_gregset (sparc_gregset, regcache, -1, ®s); 174 if (regnum != -1) 175 return; 176 } 177 178 if (regnum == -1 || sparc_fpregset_supplies_p (regnum)) 179 { 180 fpregset_t fpregs; 181 182 if (ptrace (PTRACE_GETFPREGS, pid, (PTRACE_TYPE_ARG3) &fpregs, 0) == -1) 183 perror_with_name ("Couldn't get floating point status"); 184 185 sparc_supply_fpregset (regcache, -1, &fpregs); 186 } 187 } 188 189 void 190 store_inferior_registers (int regnum) 191 { 192 struct regcache *regcache = current_regcache; 193 int pid; 194 195 /* NOTE: cagney/2002-12-02: See comment in fetch_inferior_registers 196 about threaded assumptions. */ 197 pid = TIDGET (inferior_ptid); 198 if (pid == 0) 199 pid = PIDGET (inferior_ptid); 200 201 if (regnum == -1 || sparc_gregset_supplies_p (regnum)) 202 { 203 gregset_t regs; 204 205 if (ptrace (PTRACE_GETREGS, pid, (PTRACE_TYPE_ARG3) ®s, 0) == -1) 206 perror_with_name ("Couldn't get registers"); 207 208 sparc_collect_gregset (sparc_gregset, regcache, regnum, ®s); 209 210 if (ptrace (PTRACE_SETREGS, pid, (PTRACE_TYPE_ARG3) ®s, 0) == -1) 211 perror_with_name ("Couldn't write registers"); 212 213 /* Deal with the stack regs. */ 214 if (regnum == -1 || regnum == SPARC_SP_REGNUM 215 || (regnum >= SPARC_L0_REGNUM && regnum <= SPARC_I7_REGNUM)) 216 { 217 ULONGEST sp; 218 219 regcache_cooked_read_unsigned (regcache, SPARC_SP_REGNUM, &sp); 220 sparc_collect_rwindow (regcache, sp, regnum); 221 } 222 223 if (regnum != -1) 224 return; 225 } 226 227 if (regnum == -1 || sparc_fpregset_supplies_p (regnum)) 228 { 229 fpregset_t fpregs, saved_fpregs; 230 231 if (ptrace (PTRACE_GETFPREGS, pid, (PTRACE_TYPE_ARG3) &fpregs, 0) == -1) 232 perror_with_name ("Couldn't get floating-point registers"); 233 234 memcpy (&saved_fpregs, &fpregs, sizeof (fpregs)); 235 sparc_collect_fpregset (regcache, regnum, &fpregs); 236 237 /* Writing the floating-point registers will fail on NetBSD with 238 EINVAL if the inferior process doesn't have an FPU state 239 (i.e. if it didn't use the FPU yet). Therefore we don't try 240 to write the registers if nothing changed. */ 241 if (memcmp (&saved_fpregs, &fpregs, sizeof (fpregs)) != 0) 242 { 243 if (ptrace (PTRACE_SETFPREGS, pid, 244 (PTRACE_TYPE_ARG3) &fpregs, 0) == -1) 245 perror_with_name ("Couldn't write floating-point registers"); 246 } 247 248 if (regnum != -1) 249 return; 250 } 251 } 252 253 254 /* Fetch StackGhost Per-Process XOR cookie. */ 255 256 LONGEST 257 sparc_xfer_wcookie (struct target_ops *ops, enum target_object object, 258 const char *annex, void *readbuf, const void *writebuf, 259 ULONGEST offset, LONGEST len) 260 { 261 unsigned long wcookie = 0; 262 char *buf = (char *)&wcookie; 263 264 gdb_assert (object == TARGET_OBJECT_WCOOKIE); 265 gdb_assert (readbuf && writebuf == NULL); 266 267 if (offset >= sizeof (unsigned long)) 268 return -1; 269 270 #ifdef PT_WCOOKIE 271 /* If PT_WCOOKIE is defined (by <sys/ptrace.h>), assume we're 272 running on an OpenBSD release that uses StackGhost (3.1 or 273 later). As of release 3.4, OpenBSD doesn't use a randomized 274 cookie yet, but a future release probably will. */ 275 { 276 int pid; 277 278 pid = TIDGET (inferior_ptid); 279 if (pid == 0) 280 pid = PIDGET (inferior_ptid); 281 282 /* Sanity check. The proper type for a cookie is register_t, but 283 we can't assume that this type exists on all systems supported 284 by the code in this file. */ 285 gdb_assert (sizeof (wcookie) == sizeof (register_t)); 286 287 /* Fetch the cookie. */ 288 if (ptrace (PT_WCOOKIE, pid, (PTRACE_TYPE_ARG3) &wcookie, 0) == -1) 289 { 290 if (errno != EINVAL) 291 perror_with_name ("Couldn't get StackGhost cookie"); 292 293 /* Although PT_WCOOKIE is defined on OpenBSD 3.1 and later, 294 the request wasn't implemented until after OpenBSD 3.4. If 295 the kernel doesn't support the PT_WCOOKIE request, assume 296 we're running on a kernel that uses non-randomized cookies. */ 297 wcookie = 0x3; 298 } 299 } 300 #endif /* PT_WCOOKIE */ 301 302 if (len > sizeof (unsigned long) - offset) 303 len = sizeof (unsigned long) - offset; 304 305 memcpy (readbuf, buf + offset, len); 306 return len; 307 } 308 309 LONGEST (*inf_ptrace_xfer_partial) (struct target_ops *, enum target_object, 310 const char *, void *, const void *, 311 ULONGEST, LONGEST); 312 313 static LONGEST 314 sparc_xfer_partial (struct target_ops *ops, enum target_object object, 315 const char *annex, void *readbuf, const void *writebuf, 316 ULONGEST offset, LONGEST len) 317 { 318 if (object == TARGET_OBJECT_WCOOKIE) 319 return sparc_xfer_wcookie (ops, object, annex, readbuf, writebuf, 320 offset, len); 321 322 return inf_ptrace_xfer_partial (ops, object, annex, readbuf, writebuf, 323 offset, len); 324 } 325 326 /* Create a prototype generic SPARC target. The client can override 327 it with local methods. */ 328 329 struct target_ops * 330 sparc_target (void) 331 { 332 struct target_ops *t; 333 334 t = inf_ptrace_target (); 335 t->to_fetch_registers = fetch_inferior_registers; 336 t->to_store_registers = store_inferior_registers; 337 inf_ptrace_xfer_partial = t->to_xfer_partial; 338 t->to_xfer_partial = sparc_xfer_partial; 339 return t; 340 } 341 342 343 /* Provide a prototype to silence -Wmissing-prototypes. */ 344 void _initialize_sparc_nat (void); 345 346 void 347 _initialize_sparc_nat (void) 348 { 349 /* Deafult to using SunOS 4 register sets. */ 350 if (sparc_gregset == NULL) 351 sparc_gregset = &sparc32_sunos4_gregset; 352 if (sparc_supply_gregset == NULL) 353 sparc_supply_gregset = sparc32_supply_gregset; 354 if (sparc_collect_gregset == NULL) 355 sparc_collect_gregset = sparc32_collect_gregset; 356 if (sparc_supply_fpregset == NULL) 357 sparc_supply_fpregset = sparc32_supply_fpregset; 358 if (sparc_collect_fpregset == NULL) 359 sparc_collect_fpregset = sparc32_collect_fpregset; 360 if (sparc_gregset_supplies_p == NULL) 361 sparc_gregset_supplies_p = sparc32_gregset_supplies_p; 362 if (sparc_fpregset_supplies_p == NULL) 363 sparc_fpregset_supplies_p = sparc32_fpregset_supplies_p; 364 } 365