The Design and Implementation of the FreeBSD Operating System, Second Edition
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FreeBSD/Linux Kernel Cross Reference
sys/amd64/amd64/db_trace.c

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    1 /*-
    2  * Mach Operating System
    3  * Copyright (c) 1991,1990 Carnegie Mellon University
    4  * All Rights Reserved.
    5  *
    6  * Permission to use, copy, modify and distribute this software and its
    7  * documentation is hereby granted, provided that both the copyright
    8  * notice and this permission notice appear in all copies of the
    9  * software, derivative works or modified versions, and any portions
   10  * thereof, and that both notices appear in supporting documentation.
   11  *
   12  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS
   13  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
   14  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
   15  *
   16  * Carnegie Mellon requests users of this software to return to
   17  *
   18  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
   19  *  School of Computer Science
   20  *  Carnegie Mellon University
   21  *  Pittsburgh PA 15213-3890
   22  *
   23  * any improvements or extensions that they make and grant Carnegie the
   24  * rights to redistribute these changes.
   25  */
   26 
   27 #include <sys/cdefs.h>
   28 __FBSDID("$FreeBSD: releng/6.3/sys/amd64/amd64/db_trace.c 173886 2007-11-24 19:45:58Z cvs2svn $");
   29 
   30 #include <sys/param.h>
   31 #include <sys/systm.h>
   32 #include <sys/kdb.h>
   33 #include <sys/proc.h>
   34 #include <sys/stack.h>
   35 #include <sys/sysent.h>
   36 
   37 #include <machine/cpu.h>
   38 #include <machine/md_var.h>
   39 #include <machine/pcb.h>
   40 #include <machine/reg.h>
   41 
   42 #include <vm/vm.h>
   43 #include <vm/vm_param.h>
   44 #include <vm/pmap.h>
   45 
   46 #include <ddb/ddb.h>
   47 #include <ddb/db_access.h>
   48 #include <ddb/db_sym.h>
   49 #include <ddb/db_variables.h>
   50 
   51 static db_varfcn_t db_dr0;
   52 static db_varfcn_t db_dr1;
   53 static db_varfcn_t db_dr2;
   54 static db_varfcn_t db_dr3;
   55 static db_varfcn_t db_dr4;
   56 static db_varfcn_t db_dr5;
   57 static db_varfcn_t db_dr6;
   58 static db_varfcn_t db_dr7;
   59 static db_varfcn_t db_frame;
   60 static db_varfcn_t db_rsp;
   61 static db_varfcn_t db_ss;
   62 
   63 /*
   64  * Machine register set.
   65  */
   66 #define DB_OFFSET(x)    (db_expr_t *)offsetof(struct trapframe, x)
   67 struct db_variable db_regs[] = {
   68         { "cs",         DB_OFFSET(tf_cs),       db_frame },
   69 #if 0
   70         { "ds",         DB_OFFSET(tf_ds),       db_frame },
   71         { "es",         DB_OFFSET(tf_es),       db_frame },
   72         { "fs",         DB_OFFSET(tf_fs),       db_frame },
   73         { "gs",         DB_OFFSET(tf_gs),       db_frame },
   74 #endif
   75         { "ss",         NULL,                   db_ss },
   76         { "rax",        DB_OFFSET(tf_rax),      db_frame },
   77         { "rcx",        DB_OFFSET(tf_rcx),      db_frame },
   78         { "rdx",        DB_OFFSET(tf_rdx),      db_frame },
   79         { "rbx",        DB_OFFSET(tf_rbx),      db_frame },
   80         { "rsp",        NULL,                   db_rsp },
   81         { "rbp",        DB_OFFSET(tf_rbp),      db_frame },
   82         { "rsi",        DB_OFFSET(tf_rsi),      db_frame },
   83         { "rdi",        DB_OFFSET(tf_rdi),      db_frame },
   84         { "r8",         DB_OFFSET(tf_r8),       db_frame },
   85         { "r9",         DB_OFFSET(tf_r9),       db_frame },
   86         { "r10",        DB_OFFSET(tf_r10),      db_frame },
   87         { "r11",        DB_OFFSET(tf_r11),      db_frame },
   88         { "r12",        DB_OFFSET(tf_r12),      db_frame },
   89         { "r13",        DB_OFFSET(tf_r13),      db_frame },
   90         { "r14",        DB_OFFSET(tf_r14),      db_frame },
   91         { "r15",        DB_OFFSET(tf_r15),      db_frame },
   92         { "rip",        DB_OFFSET(tf_rip),      db_frame },
   93         { "rflags",     DB_OFFSET(tf_rflags),   db_frame },
   94         { "dr0",        NULL,                   db_dr0 },
   95         { "dr1",        NULL,                   db_dr1 },
   96         { "dr2",        NULL,                   db_dr2 },
   97         { "dr3",        NULL,                   db_dr3 },
   98         { "dr4",        NULL,                   db_dr4 },
   99         { "dr5",        NULL,                   db_dr5 },
  100         { "dr6",        NULL,                   db_dr6 },
  101         { "dr7",        NULL,                   db_dr7 },
  102 };
  103 struct db_variable *db_eregs = db_regs + sizeof(db_regs)/sizeof(db_regs[0]);
  104 
  105 #define DB_DRX_FUNC(reg)                \
  106 static int                              \
  107 db_ ## reg (vp, valuep, op)             \
  108         struct db_variable *vp;         \
  109         db_expr_t * valuep;             \
  110         int op;                         \
  111 {                                       \
  112         if (op == DB_VAR_GET)           \
  113                 *valuep = r ## reg ();  \
  114         else                            \
  115                 load_ ## reg (*valuep); \
  116         return (1);                     \
  117 }
  118 
  119 DB_DRX_FUNC(dr0)
  120 DB_DRX_FUNC(dr1)
  121 DB_DRX_FUNC(dr2)
  122 DB_DRX_FUNC(dr3)
  123 DB_DRX_FUNC(dr4)
  124 DB_DRX_FUNC(dr5)
  125 DB_DRX_FUNC(dr6)
  126 DB_DRX_FUNC(dr7)
  127 
  128 static __inline long
  129 get_rsp(struct trapframe *tf)
  130 {
  131         return ((ISPL(tf->tf_cs)) ? tf->tf_rsp :
  132             (db_expr_t)tf + offsetof(struct trapframe, tf_rsp));
  133 }
  134 
  135 static int
  136 db_frame(struct db_variable *vp, db_expr_t *valuep, int op)
  137 {
  138         long *reg;
  139 
  140         if (kdb_frame == NULL)
  141                 return (0);
  142 
  143         reg = (long *)((uintptr_t)kdb_frame + (db_expr_t)vp->valuep);
  144         if (op == DB_VAR_GET)
  145                 *valuep = *reg;
  146         else
  147                 *reg = *valuep;
  148         return (1);
  149 }
  150 
  151 static int
  152 db_rsp(struct db_variable *vp, db_expr_t *valuep, int op)
  153 {
  154 
  155         if (kdb_frame == NULL)
  156                 return (0);
  157 
  158         if (op == DB_VAR_GET)
  159                 *valuep = get_rsp(kdb_frame);
  160         else if (ISPL(kdb_frame->tf_cs))
  161                 kdb_frame->tf_rsp = *valuep;
  162         return (1);
  163 }
  164 
  165 static int
  166 db_ss(struct db_variable *vp, db_expr_t *valuep, int op)
  167 {
  168 
  169         if (kdb_frame == NULL)
  170                 return (0);
  171 
  172         if (op == DB_VAR_GET)
  173                 *valuep = (ISPL(kdb_frame->tf_cs)) ? kdb_frame->tf_ss : rss();
  174         else if (ISPL(kdb_frame->tf_cs))
  175                 kdb_frame->tf_ss = *valuep;
  176         return (1);
  177 }
  178 
  179 /*
  180  * Stack trace.
  181  */
  182 #define INKERNEL(va) (((va) >= DMAP_MIN_ADDRESS && (va) < DMAP_MAX_ADDRESS) \
  183             || ((va) >= KERNBASE && (va) < VM_MAX_KERNEL_ADDRESS))
  184 
  185 struct amd64_frame {
  186         struct amd64_frame      *f_frame;
  187         long                    f_retaddr;
  188         long                    f_arg0;
  189 };
  190 
  191 #define NORMAL          0
  192 #define TRAP            1
  193 #define INTERRUPT       2
  194 #define SYSCALL         3
  195 
  196 static void db_nextframe(struct amd64_frame **, db_addr_t *, struct thread *);
  197 static int db_numargs(struct amd64_frame *);
  198 static void db_print_stack_entry(const char *, int, char **, long *, db_addr_t);
  199 static void decode_syscall(int, struct thread *);
  200 
  201 static char * watchtype_str(int type);
  202 int  amd64_set_watch(int watchnum, unsigned int watchaddr, int size, int access,
  203                     struct dbreg * d);
  204 int  amd64_clr_watch(int watchnum, struct dbreg * d);
  205 int  db_md_set_watchpoint(db_expr_t addr, db_expr_t size);
  206 int  db_md_clr_watchpoint(db_expr_t addr, db_expr_t size);
  207 void db_md_list_watchpoints(void);
  208 
  209 /*
  210  * Figure out how many arguments were passed into the frame at "fp".
  211  */
  212 static int
  213 db_numargs(fp)
  214         struct amd64_frame *fp;
  215 {
  216 #if 1
  217         return (0);     /* regparm, needs dwarf2 info */
  218 #else
  219         long    *argp;
  220         int     inst;
  221         int     args;
  222 
  223         argp = (long *)db_get_value((long)&fp->f_retaddr, 8, FALSE);
  224         /*
  225          * XXX etext is wrong for LKMs.  We should attempt to interpret
  226          * the instruction at the return address in all cases.  This
  227          * may require better fault handling.
  228          */
  229         if (argp < (long *)btext || argp >= (long *)etext) {
  230                 args = 5;
  231         } else {
  232                 inst = db_get_value((long)argp, 4, FALSE);
  233                 if ((inst & 0xff) == 0x59)      /* popl %ecx */
  234                         args = 1;
  235                 else if ((inst & 0xffff) == 0xc483)     /* addl $Ibs, %esp */
  236                         args = ((inst >> 16) & 0xff) / 4;
  237                 else
  238                         args = 5;
  239         }
  240         return (args);
  241 #endif
  242 }
  243 
  244 static void
  245 db_print_stack_entry(name, narg, argnp, argp, callpc)
  246         const char *name;
  247         int narg;
  248         char **argnp;
  249         long *argp;
  250         db_addr_t callpc;
  251 {
  252         db_printf("%s(", name);
  253 #if 0
  254         while (narg) {
  255                 if (argnp)
  256                         db_printf("%s=", *argnp++);
  257                 db_printf("%lr", (long)db_get_value((long)argp, 8, FALSE));
  258                 argp++;
  259                 if (--narg != 0)
  260                         db_printf(",");
  261         }
  262 #endif
  263         db_printf(") at ");
  264         db_printsym(callpc, DB_STGY_PROC);
  265         db_printf("\n");
  266 }
  267 
  268 static void
  269 decode_syscall(int number, struct thread *td)
  270 {
  271         struct proc *p;
  272         c_db_sym_t sym;
  273         db_expr_t diff;
  274         sy_call_t *f;
  275         const char *symname;
  276 
  277         db_printf(" (%d", number);
  278         p = (td != NULL) ? td->td_proc : NULL;
  279         if (p != NULL && 0 <= number && number < p->p_sysent->sv_size) {
  280                 f = p->p_sysent->sv_table[number].sy_call;
  281                 sym = db_search_symbol((db_addr_t)f, DB_STGY_ANY, &diff);
  282                 if (sym != DB_SYM_NULL && diff == 0) {
  283                         db_symbol_values(sym, &symname, NULL);
  284                         db_printf(", %s, %s", p->p_sysent->sv_name, symname);
  285                 }
  286         }
  287         db_printf(")");
  288 }
  289 
  290 /*
  291  * Figure out the next frame up in the call stack.
  292  */
  293 static void
  294 db_nextframe(struct amd64_frame **fp, db_addr_t *ip, struct thread *td)
  295 {
  296         struct trapframe *tf;
  297         int frame_type;
  298         long rip, rsp, rbp;
  299         db_expr_t offset;
  300         c_db_sym_t sym;
  301         const char *name;
  302 
  303         rip = db_get_value((long) &(*fp)->f_retaddr, 8, FALSE);
  304         rbp = db_get_value((long) &(*fp)->f_frame, 8, FALSE);
  305 
  306         /*
  307          * Figure out frame type.  We look at the address just before
  308          * the saved instruction pointer as the saved EIP is after the
  309          * call function, and if the function being called is marked as
  310          * dead (such as panic() at the end of dblfault_handler()), then
  311          * the instruction at the saved EIP will be part of a different
  312          * function (syscall() in this example) rather than the one that
  313          * actually made the call.
  314          */
  315         frame_type = NORMAL;
  316         sym = db_search_symbol(rip - 1, DB_STGY_ANY, &offset);
  317         db_symbol_values(sym, &name, NULL);
  318         if (name != NULL) {
  319                 if (strcmp(name, "calltrap") == 0 ||
  320                     strcmp(name, "fork_trampoline") == 0 ||
  321                     strcmp(name, "nmi_calltrap") == 0 ||
  322                     strcmp(name, "Xdblfault") == 0)
  323                         frame_type = TRAP;
  324                 else if (strncmp(name, "Xatpic_intr", 11) == 0 ||
  325                     strncmp(name, "Xatpic_fastintr", 15) == 0 ||
  326                     strncmp(name, "Xapic_isr", 9) == 0)
  327                         frame_type = INTERRUPT;
  328                 else if (strcmp(name, "Xfast_syscall") == 0)
  329                         frame_type = SYSCALL;
  330         }
  331 
  332         /*
  333          * Normal frames need no special processing.
  334          */
  335         if (frame_type == NORMAL) {
  336                 *ip = (db_addr_t) rip;
  337                 *fp = (struct amd64_frame *) rbp;
  338                 return;
  339         }
  340 
  341         db_print_stack_entry(name, 0, 0, 0, rip);
  342 
  343         /*
  344          * Point to base of trapframe which is just above the
  345          * current frame.
  346          */
  347         tf = (struct trapframe *)((long)*fp + 16);
  348 
  349         if (INKERNEL((long) tf)) {
  350                 rsp = get_rsp(tf);
  351                 rip = tf->tf_rip;
  352                 rbp = tf->tf_rbp;
  353                 switch (frame_type) {
  354                 case TRAP:
  355                         db_printf("--- trap %#lr", tf->tf_trapno);
  356                         break;
  357                 case SYSCALL:
  358                         db_printf("--- syscall");
  359                         decode_syscall(tf->tf_rax, td);
  360                         break;
  361                 case INTERRUPT:
  362                         db_printf("--- interrupt");
  363                         break;
  364                 default:
  365                         panic("The moon has moved again.");
  366                 }
  367                 db_printf(", rip = %#lr, rsp = %#lr, rbp = %#lr ---\n", rip,
  368                     rsp, rbp);
  369         }
  370 
  371         *ip = (db_addr_t) rip;
  372         *fp = (struct amd64_frame *) rbp;
  373 }
  374 
  375 static int
  376 db_backtrace(struct thread *td, struct trapframe *tf,
  377     struct amd64_frame *frame, db_addr_t pc, int count)
  378 {
  379         struct amd64_frame *actframe;
  380 #define MAXNARG 16
  381         char *argnames[MAXNARG], **argnp = NULL;
  382         const char *name;
  383         long *argp;
  384         db_expr_t offset;
  385         c_db_sym_t sym;
  386         int narg, quit;
  387         boolean_t first;
  388 
  389         if (count == -1)
  390                 count = 1024;
  391 
  392         first = TRUE;
  393         quit = 0;
  394         db_setup_paging(db_simple_pager, &quit, db_lines_per_page);
  395         while (count-- && !quit) {
  396                 sym = db_search_symbol(pc, DB_STGY_ANY, &offset);
  397                 db_symbol_values(sym, &name, NULL);
  398 
  399                 /*
  400                  * Attempt to determine a (possibly fake) frame that gives
  401                  * the caller's pc.  It may differ from `frame' if the
  402                  * current function never sets up a standard frame or hasn't
  403                  * set one up yet or has just discarded one.  The last two
  404                  * cases can be guessed fairly reliably for code generated
  405                  * by gcc.  The first case is too much trouble to handle in
  406                  * general because the amount of junk on the stack depends
  407                  * on the pc (the special handling of "calltrap", etc. in
  408                  * db_nextframe() works because the `next' pc is special).
  409                  */
  410                 actframe = frame;
  411                 if (first) {
  412                         if (tf != NULL) {
  413                                 int instr;
  414 
  415                                 instr = db_get_value(pc, 4, FALSE);
  416                                 if ((instr & 0xffffffff) == 0xe5894855) {
  417                                         /* pushq %rbp; movq %rsp, %rbp */
  418                                         actframe = (void *)(get_rsp(tf) - 8);
  419                                 } else if ((instr & 0xffffff) == 0xe58948) {
  420                                         /* movq %rsp, %rbp */
  421                                         actframe = (void *)get_rsp(tf);
  422                                         if (tf->tf_rbp == 0) {
  423                                                 /* Fake frame better. */
  424                                                 frame = actframe;
  425                                         }
  426                                 } else if ((instr & 0xff) == 0xc3) {
  427                                         /* ret */
  428                                         actframe = (void *)(get_rsp(tf) - 8);
  429                                 } else if (offset == 0) {
  430                                         /* Probably an assembler symbol. */
  431                                         actframe = (void *)(get_rsp(tf) - 8);
  432                                 }
  433                         } else if (strcmp(name, "fork_trampoline") == 0) {
  434                                 /*
  435                                  * Don't try to walk back on a stack for a
  436                                  * process that hasn't actually been run yet.
  437                                  */
  438                                 db_print_stack_entry(name, 0, 0, 0, pc);
  439                                 break;
  440                         }
  441                         first = FALSE;
  442                 }
  443 
  444                 argp = &actframe->f_arg0;
  445                 narg = MAXNARG;
  446                 if (sym != NULL && db_sym_numargs(sym, &narg, argnames)) {
  447                         argnp = argnames;
  448                 } else {
  449                         narg = db_numargs(frame);
  450                 }
  451 
  452                 db_print_stack_entry(name, narg, argnp, argp, pc);
  453 
  454                 if (actframe != frame) {
  455                         /* `frame' belongs to caller. */
  456                         pc = (db_addr_t)
  457                             db_get_value((long)&actframe->f_retaddr, 8, FALSE);
  458                         continue;
  459                 }
  460 
  461                 db_nextframe(&frame, &pc, td);
  462 
  463                 if (INKERNEL((long)pc) && !INKERNEL((long)frame)) {
  464                         sym = db_search_symbol(pc, DB_STGY_ANY, &offset);
  465                         db_symbol_values(sym, &name, NULL);
  466                         db_print_stack_entry(name, 0, 0, 0, pc);
  467                         break;
  468                 }
  469                 if (!INKERNEL((long) frame)) {
  470                         break;
  471                 }
  472         }
  473 
  474         return (0);
  475 }
  476 
  477 void
  478 db_trace_self(void)
  479 {
  480         struct amd64_frame *frame;
  481         db_addr_t callpc;
  482         register_t rbp;
  483 
  484         __asm __volatile("movq %%rbp,%0" : "=r" (rbp));
  485         frame = (struct amd64_frame *)rbp;
  486         callpc = (db_addr_t)db_get_value((long)&frame->f_retaddr, 8, FALSE);
  487         frame = frame->f_frame;
  488         db_backtrace(curthread, NULL, frame, callpc, -1);
  489 }
  490 
  491 int
  492 db_trace_thread(struct thread *thr, int count)
  493 {
  494         struct pcb *ctx;
  495 
  496         ctx = kdb_thr_ctx(thr);
  497         return (db_backtrace(thr, NULL, (struct amd64_frame *)ctx->pcb_rbp,
  498                     ctx->pcb_rip, count));
  499 }
  500 
  501 void
  502 stack_save(struct stack *st)
  503 {
  504         struct amd64_frame *frame;
  505         vm_offset_t callpc;
  506         register_t rbp;
  507 
  508         stack_zero(st);
  509         __asm __volatile("movq %%rbp,%0" : "=r" (rbp));
  510         frame = (struct amd64_frame *)rbp;
  511         while (1) {
  512                 if (!INKERNEL((long)frame))
  513                         break;
  514                 callpc = frame->f_retaddr;
  515                 if (!INKERNEL(callpc))
  516                         break;
  517                 if (stack_put(st, callpc) == -1)
  518                         break;
  519                 if (frame->f_frame <= frame ||
  520                     (vm_offset_t)frame->f_frame >=
  521                     (vm_offset_t)rbp + KSTACK_PAGES * PAGE_SIZE)
  522                         break;
  523                 frame = frame->f_frame;
  524         }
  525 }
  526 
  527 int
  528 amd64_set_watch(watchnum, watchaddr, size, access, d)
  529         int watchnum;
  530         unsigned int watchaddr;
  531         int size;
  532         int access;
  533         struct dbreg * d;
  534 {
  535         int i;
  536         unsigned int mask;
  537         
  538         if (watchnum == -1) {
  539                 for (i = 0, mask = 0x3; i < 4; i++, mask <<= 2)
  540                         if ((d->dr[7] & mask) == 0)
  541                                 break;
  542                 if (i < 4)
  543                         watchnum = i;
  544                 else
  545                         return (-1);
  546         }
  547         
  548         switch (access) {
  549         case DBREG_DR7_EXEC:
  550                 size = 1; /* size must be 1 for an execution breakpoint */
  551                 /* fall through */
  552         case DBREG_DR7_WRONLY:
  553         case DBREG_DR7_RDWR:
  554                 break;
  555         default : return (-1);
  556         }
  557         
  558         /*
  559          * we can watch a 1, 2, or 4 byte sized location
  560          */
  561         switch (size) {
  562         case 1  : mask = 0x00; break;
  563         case 2  : mask = 0x01 << 2; break;
  564         case 4  : mask = 0x03 << 2; break;
  565         default : return (-1);
  566         }
  567 
  568         mask |= access;
  569 
  570         /* clear the bits we are about to affect */
  571         d->dr[7] &= ~((0x3 << (watchnum*2)) | (0x0f << (watchnum*4+16)));
  572 
  573         /* set drN register to the address, N=watchnum */
  574         DBREG_DRX(d,watchnum) = watchaddr;
  575 
  576         /* enable the watchpoint */
  577         d->dr[7] |= (0x2 << (watchnum*2)) | (mask << (watchnum*4+16));
  578 
  579         return (watchnum);
  580 }
  581 
  582 
  583 int
  584 amd64_clr_watch(watchnum, d)
  585         int watchnum;
  586         struct dbreg * d;
  587 {
  588 
  589         if (watchnum < 0 || watchnum >= 4)
  590                 return (-1);
  591         
  592         d->dr[7] = d->dr[7] & ~((0x3 << (watchnum*2)) | (0x0f << (watchnum*4+16)));
  593         DBREG_DRX(d,watchnum) = 0;
  594         
  595         return (0);
  596 }
  597 
  598 
  599 int
  600 db_md_set_watchpoint(addr, size)
  601         db_expr_t addr;
  602         db_expr_t size;
  603 {
  604         int avail, wsize;
  605         int i;
  606         struct dbreg d;
  607         
  608         fill_dbregs(NULL, &d);
  609         
  610         avail = 0;
  611         for(i=0; i<4; i++) {
  612                 if ((d.dr[7] & (3 << (i*2))) == 0)
  613                         avail++;
  614         }
  615         
  616         if (avail*4 < size)
  617                 return (-1);
  618         
  619         for (i=0; i<4 && (size != 0); i++) {
  620                 if ((d.dr[7] & (3<<(i*2))) == 0) {
  621                         if (size > 4)
  622                                 wsize = 4;
  623                         else
  624                                 wsize = size;
  625                         if (wsize == 3)
  626                                 wsize++;
  627                         amd64_set_watch(i, addr, wsize, 
  628                                        DBREG_DR7_WRONLY, &d);
  629                         addr += wsize;
  630                         size -= wsize;
  631                 }
  632         }
  633         
  634         set_dbregs(NULL, &d);
  635         
  636         return(0);
  637 }
  638 
  639 
  640 int
  641 db_md_clr_watchpoint(addr, size)
  642         db_expr_t addr;
  643         db_expr_t size;
  644 {
  645         int i;
  646         struct dbreg d;
  647 
  648         fill_dbregs(NULL, &d);
  649 
  650         for(i=0; i<4; i++) {
  651                 if (d.dr[7] & (3 << (i*2))) {
  652                         if ((DBREG_DRX((&d), i) >= addr) && 
  653                             (DBREG_DRX((&d), i) < addr+size))
  654                                 amd64_clr_watch(i, &d);
  655                         
  656                 }
  657         }
  658         
  659         set_dbregs(NULL, &d);
  660         
  661         return(0);
  662 }
  663 
  664 
  665 static 
  666 char *
  667 watchtype_str(type)
  668         int type;
  669 {
  670         switch (type) {
  671                 case DBREG_DR7_EXEC   : return "execute";    break;
  672                 case DBREG_DR7_RDWR   : return "read/write"; break;
  673                 case DBREG_DR7_WRONLY : return "write";      break;
  674                 default               : return "invalid";    break;
  675         }
  676 }
  677 
  678 
  679 void
  680 db_md_list_watchpoints()
  681 {
  682         int i;
  683         struct dbreg d;
  684 
  685         fill_dbregs(NULL, &d);
  686 
  687         db_printf("\nhardware watchpoints:\n");
  688         db_printf("  watch    status        type  len     address\n");
  689         db_printf("  -----  --------  ----------  ---  ----------\n");
  690         for (i=0; i<4; i++) {
  691                 if (d.dr[7] & (0x03 << (i*2))) {
  692                         unsigned type, len;
  693                         type = (d.dr[7] >> (16+(i*4))) & 3;
  694                         len =  (d.dr[7] >> (16+(i*4)+2)) & 3;
  695                         db_printf("  %-5d  %-8s  %10s  %3d  0x%016lx\n",
  696                                   i, "enabled", watchtype_str(type), 
  697                                   len + 1, DBREG_DRX((&d), i));
  698                 }
  699                 else {
  700                         db_printf("  %-5d  disabled\n", i);
  701                 }
  702         }
  703         
  704         db_printf("\ndebug register values:\n");
  705         for (i=0; i<8; i++) {
  706                 db_printf("  dr%d 0x%016lx\n", i, DBREG_DRX((&d), i));
  707         }
  708         db_printf("\n");
  709 }

Cache object: ed4f3b634b5310c0e274f5e01b68af98


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