gnu/usr.bin/gdb/kgdb/trgt_x86_64.c

   1 /*
   2  * Copyright (c) 2004 Marcel Moolenaar
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  *
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
  16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  18  * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  25  *
  26  * $FreeBSD: src/gnu/usr.bin/gdb/kgdb/trgt_amd64.c,v 1.10 2008/05/01 20:36:48 jhb Exp $
  27  */
  28
  29 #include <sys/cdefs.h>
  30
  31 #include <sys/types.h>
  32 #include <sys/thread.h>
  33 #include <machine/pcb.h>
  34 #include <machine/frame.h>
  35 #include <err.h>
  36 #include <kvm.h>
  37 #include <string.h>
  38
  39 #include <defs.h>
  40 #include <target.h>
  41 #include <gdbthread.h>
  42 #include <inferior.h>
  43 #include <regcache.h>
  44 #include <frame-unwind.h>
  45 #include <amd64-tdep.h>
  46
  47 #include "kgdb.h"
  48
  49 static int
  50 kgdb_trgt_trapframe_sniffer(const struct frame_unwind *self,
  51                             struct frame_info *next_frame,
  52                             void **this_prologue_cache);
  53
  54 void
  55 kgdb_trgt_fetch_registers(struct target_ops *target_ops, struct regcache *regcache, int regno)
  56 {
  57         struct kthr *kt;
  58         struct pcb pcb;
  59
  60         kt = kgdb_thr_lookup_tid(ptid_get_tid(inferior_ptid));
  61         if (kt == NULL) {
  62                 regcache_raw_supply(regcache, regno, NULL);
  63                 return;
  64         }
  65
  66         /*
  67          * kt->pcb == 0 is a marker for "non-dumping kernel thread".
  68          */
  69         if (kt->pcb == 0) {
  70                 uintptr_t regs[7];
  71                 uintptr_t addr;
  72                 uintptr_t sp;
  73
  74                 addr = kt->kaddr + offsetof(struct thread, td_sp);
  75                 kvm_read(kvm, addr, &sp, sizeof(sp));
  76                 /*
  77                  * Stack is:
  78                  * -2 ret
  79                  * -1 popfq
  80                  * 0 popq %r15  edi
  81                  * 1 popq %r14
  82                  * 2 popq %r13
  83                  * 3 popq %r12
  84                  * 4 popq %rbx
  85                  * 5 popq %rbp
  86                  * 6 ret
  87                  */
  88                 if (kvm_read(kvm, sp + 2 * sizeof(regs[0]), regs, sizeof(regs)) != sizeof(regs)) {
  89                         warnx("kvm_read: %s", kvm_geterr(kvm));
  90                         memset(regs, 0, sizeof(regs));
  91                 }
  92                 regcache_raw_supply(regcache, AMD64_R8_REGNUM + 7, &regs[0]);
  93                 regcache_raw_supply(regcache, AMD64_R8_REGNUM + 6, &regs[1]);
  94                 regcache_raw_supply(regcache, AMD64_R8_REGNUM + 5, &regs[2]);
  95                 regcache_raw_supply(regcache, AMD64_R8_REGNUM + 4, &regs[3]);
  96                 regcache_raw_supply(regcache, AMD64_RBX_REGNUM, &regs[4]);
  97                 regcache_raw_supply(regcache, AMD64_RBP_REGNUM, &regs[5]);
  98                 regcache_raw_supply(regcache, AMD64_RIP_REGNUM, &regs[6]);
  99                 sp += 9 * sizeof(regs[0]);
 100                 regcache_raw_supply(regcache, AMD64_RSP_REGNUM, &sp);
 101                 return;
 102         }
 103
 104         if (kvm_read(kvm, kt->pcb, &pcb, sizeof(pcb)) != sizeof(pcb)) {
 105                 warnx("kvm_read: %s", kvm_geterr(kvm));
 106                 memset(&pcb, 0, sizeof(pcb));
 107         }
 108
 109         regcache_raw_supply(regcache, AMD64_RBX_REGNUM, (char *)&pcb.pcb_rbx);
 110         regcache_raw_supply(regcache, AMD64_RBP_REGNUM, (char *)&pcb.pcb_rbp);
 111         regcache_raw_supply(regcache, AMD64_RSP_REGNUM, (char *)&pcb.pcb_rsp);
 112         regcache_raw_supply(regcache, AMD64_R8_REGNUM + 4, (char *)&pcb.pcb_r12);
 113         regcache_raw_supply(regcache, AMD64_R8_REGNUM + 5, (char *)&pcb.pcb_r13);
 114         regcache_raw_supply(regcache, AMD64_R8_REGNUM + 6, (char *)&pcb.pcb_r14);
 115         regcache_raw_supply(regcache, AMD64_R15_REGNUM, (char *)&pcb.pcb_r15);
 116         regcache_raw_supply(regcache, AMD64_RIP_REGNUM, (char *)&pcb.pcb_rip);
 117 }
 118
 119 struct kgdb_frame_cache {
 120         int             frame_type;
 121         CORE_ADDR       pc;
 122         CORE_ADDR       sp;
 123 };
 124
 125 #define FT_NORMAL               1
 126 #define FT_INTRFRAME            2
 127 /*#define       FT_INTRTRAPFRAME        3*/
 128 #define FT_TIMERFRAME           4
 129 #define FT_CALLTRAP             5
 130
 131 static int kgdb_trgt_frame_offset[20] = {
 132         offsetof(struct trapframe, tf_rax),
 133         offsetof(struct trapframe, tf_rbx),
 134         offsetof(struct trapframe, tf_rcx),
 135         offsetof(struct trapframe, tf_rdx),
 136         offsetof(struct trapframe, tf_rsi),
 137         offsetof(struct trapframe, tf_rdi),
 138         offsetof(struct trapframe, tf_rbp),
 139         offsetof(struct trapframe, tf_rsp),
 140         offsetof(struct trapframe, tf_r8),
 141         offsetof(struct trapframe, tf_r9),
 142         offsetof(struct trapframe, tf_r10),
 143         offsetof(struct trapframe, tf_r11),
 144         offsetof(struct trapframe, tf_r12),
 145         offsetof(struct trapframe, tf_r13),
 146         offsetof(struct trapframe, tf_r14),
 147         offsetof(struct trapframe, tf_r15),
 148         offsetof(struct trapframe, tf_rip),
 149         offsetof(struct trapframe, tf_rflags),
 150         offsetof(struct trapframe, tf_cs),
 151         offsetof(struct trapframe, tf_ss)
 152 };
 153
 154 static struct kgdb_frame_cache *
 155 kgdb_trgt_frame_cache(struct frame_info *next_frame, void **this_cache)
 156 {
 157         struct kgdb_frame_cache *cache;
 158         char *pname;
 159
 160         cache = *this_cache;
 161         if (cache == NULL) {
 162                 cache = FRAME_OBSTACK_ZALLOC(struct kgdb_frame_cache);
 163                 *this_cache = cache;
 164                 cache->pc = get_frame_address_in_block(next_frame);
 165                 cache->sp = get_frame_sp(next_frame);
 166                 find_pc_partial_function(cache->pc, &pname, NULL, NULL);
 167
 168                 if (strcmp(pname, "calltrap") == 0)
 169                         cache->frame_type = FT_CALLTRAP;
 170                 else if (pname[0] != 'X')
 171                         cache->frame_type = FT_NORMAL;
 172                 else if (strcmp(pname, "Xtimerint") == 0)
 173                         cache->frame_type = FT_TIMERFRAME;
 174                 else
 175                         cache->frame_type = FT_INTRFRAME;
 176         }
 177         return (cache);
 178 }
 179
 180 static void
 181 kgdb_trgt_trapframe_this_id(struct frame_info *next_frame, void **this_cache,
 182     struct frame_id *this_id)
 183 {
 184         struct kgdb_frame_cache *cache;
 185
 186         cache = kgdb_trgt_frame_cache(next_frame, this_cache);
 187         *this_id = frame_id_build(cache->sp, cache->pc);
 188 }
 189
 190 static struct value *
 191 kgdb_trgt_trapframe_prev_register(struct frame_info *next_frame,
 192     void **this_cache, int regnum)
 193 {
 194         CORE_ADDR addrp;
 195         struct kgdb_frame_cache *cache;
 196         int ofs;
 197
 198         if (regnum < AMD64_RAX_REGNUM || regnum > AMD64_EFLAGS_REGNUM + 2)
 199                 return frame_unwind_got_register(next_frame, regnum, regnum);
 200
 201         ofs = kgdb_trgt_frame_offset[regnum];
 202
 203         cache = kgdb_trgt_frame_cache(next_frame, this_cache);
 204
 205         switch (cache->frame_type) {
 206         case FT_NORMAL:
 207                 break;
 208         case FT_INTRFRAME:
 209                 ofs += 8;
 210                 break;
 211         case FT_TIMERFRAME:
 212                 break;
 213                 /*
 214         case FT_INTRTRAPFRAME:
 215                 ofs -= ofs_fix;
 216                 break;
 217                 */
 218         case FT_CALLTRAP:
 219                 ofs += 0;
 220                 break;
 221         default:
 222                 fprintf_unfiltered(gdb_stderr, "Correct FT_XXX frame offsets "
 223                    "for %d\n", cache->frame_type);
 224                 break;
 225         }
 226
 227         addrp = cache->sp + ofs;
 228         return frame_unwind_got_memory(next_frame, regnum, addrp);
 229 }
 230
 231 const struct frame_unwind kgdb_trgt_trapframe_unwind = {
 232         NORMAL_FRAME,
 233         &kgdb_trgt_trapframe_this_id,
 234         &kgdb_trgt_trapframe_prev_register,
 235         .sniffer = kgdb_trgt_trapframe_sniffer
 236 };
 237
 238 static int
 239 kgdb_trgt_trapframe_sniffer(const struct frame_unwind *self,
 240                             struct frame_info *next_frame,
 241                             void **this_prologue_cache)
 242 {
 243         char *pname;
 244         CORE_ADDR pc;
 245
 246         pc = get_frame_address_in_block(next_frame);
 247         pname = NULL;
 248         find_pc_partial_function(pc, &pname, NULL, NULL);
 249         if (pname == NULL)
 250                 return (0);
 251         if (strcmp(pname, "calltrap") == 0 ||
 252             strcmp(pname, "dblfault_handler") == 0 ||
 253             strcmp(pname, "nmi_calltrap") == 0 ||
 254             (pname[0] == 'X' && pname[1] != '_'))
 255                 return (1);
 256         return (0);
 257 }