/* Native-dependent code for BSD Unix running on i386's, for GDB. Copyright 1988, 1989, 1991, 1992 Free Software Foundation, Inc. This file is part of GDB. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. $Id: freebsd-nat.c,v 1.5 1995/04/26 01:01:07 jkh Exp $ */ #include #include #include #include #include #include #include #include "defs.h" /* this table must line up with REGISTER_NAMES in tm-i386v.h */ /* symbols like 'tEAX' come from */ static int tregmap[] = { tEAX, tECX, tEDX, tEBX, tESP, tEBP, tESI, tEDI, tEIP, tEFLAGS, tCS, tSS, tDS, tES, tSS, tSS, /* lies: no fs or gs */ }; /* blockend is the value of u.u_ar0, and points to the place where ES is stored. */ int i386_register_u_addr (blockend, regnum) int blockend; int regnum; { return (blockend + 4 * tregmap[regnum]); } #define fpstate save87 #define U_FPSTATE(u) u.u_pcb.pcb_savefpu static void i387_to_double (from, to) char *from; char *to; { long *lp; /* push extended mode on 387 stack, then pop in double mode * * first, set exception masks so no error is generated - * number will be rounded to inf or 0, if necessary */ asm ("pushl %eax"); /* grab a stack slot */ asm ("fstcw (%esp)"); /* get 387 control word */ asm ("movl (%esp),%eax"); /* save old value */ asm ("orl $0x3f,%eax"); /* mask all exceptions */ asm ("pushl %eax"); asm ("fldcw (%esp)"); /* load new value into 387 */ asm ("movl 8(%ebp),%eax"); asm ("fldt (%eax)"); /* push extended number on 387 stack */ asm ("fwait"); asm ("movl 12(%ebp),%eax"); asm ("fstpl (%eax)"); /* pop double */ asm ("fwait"); asm ("popl %eax"); /* flush modified control word */ asm ("fnclex"); /* clear exceptions */ asm ("fldcw (%esp)"); /* restore original control word */ asm ("popl %eax"); /* flush saved copy */ } #if 0 static void double_to_i387 (from, to) char *from; char *to; { /* push double mode on 387 stack, then pop in extended mode * no errors are possible because every 64-bit pattern * can be converted to an extended */ asm ("movl 8(%ebp),%eax"); asm ("fldl (%eax)"); asm ("fwait"); asm ("movl 12(%ebp),%eax"); asm ("fstpt (%eax)"); asm ("fwait"); } #endif struct env387 { unsigned short control; unsigned short r0; unsigned short status; unsigned short r1; unsigned short tag; unsigned short r2; unsigned long eip; unsigned short code_seg; unsigned short opcode; unsigned long operand; unsigned short operand_seg; unsigned short r3; unsigned char regs[8][10]; }; /* static */ void print_387_control_word (control) unsigned int control; { printf ("control 0x%04x: ", control); printf ("compute to "); switch ((control >> 8) & 3) { case 0: printf ("24 bits; "); break; case 1: printf ("(bad); "); break; case 2: printf ("53 bits; "); break; case 3: printf ("64 bits; "); break; } printf ("round "); switch ((control >> 10) & 3) { case 0: printf ("NEAREST; "); break; case 1: printf ("DOWN; "); break; case 2: printf ("UP; "); break; case 3: printf ("CHOP; "); break; } if (control & 0x3f) { printf ("mask:"); if (control & 0x0001) printf (" INVALID"); if (control & 0x0002) printf (" DENORM"); if (control & 0x0004) printf (" DIVZ"); if (control & 0x0008) printf (" OVERF"); if (control & 0x0010) printf (" UNDERF"); if (control & 0x0020) printf (" LOS"); printf (";"); } printf ("\n"); if (control & 0xe080) printf ("warning: reserved bits on 0x%x\n", control & 0xe080); } /* static */ void print_387_status_word (status) unsigned int status; { printf ("status 0x%04x: ", status); if (status & 0xff) { printf ("exceptions:"); if (status & 0x0001) printf (" INVALID"); if (status & 0x0002) printf (" DENORM"); if (status & 0x0004) printf (" DIVZ"); if (status & 0x0008) printf (" OVERF"); if (status & 0x0010) printf (" UNDERF"); if (status & 0x0020) printf (" LOS"); if (status & 0x0040) printf (" FPSTACK"); printf ("; "); } printf ("flags: %d%d%d%d; ", (status & 0x4000) != 0, (status & 0x0400) != 0, (status & 0x0200) != 0, (status & 0x0100) != 0); printf ("top %d\n", (status >> 11) & 7); } static void print_387_status (status, ep) unsigned short status; struct env387 *ep; { int i; int bothstatus; int top; int fpreg; unsigned char *p; bothstatus = ((status != 0) && (ep->status != 0)); if (status != 0) { if (bothstatus) printf ("u: "); print_387_status_word ((unsigned int)status); } if (ep->status != 0) { if (bothstatus) printf ("e: "); print_387_status_word ((unsigned int)ep->status); } print_387_control_word ((unsigned int)ep->control); printf ("opcode 0x%x; ", ep->opcode); printf ("pc 0x%x:0x%x; ", ep->code_seg, ep->eip); printf ("operand 0x%x:0x%x\n", ep->operand_seg, ep->operand); top = (ep->status >> 11) & 7; printf (" regno tag msb lsb value\n"); for (fpreg = 7; fpreg >= 0; fpreg--) { int st_regno; double val; /* The physical regno `fpreg' is only relevant as an index into the * tag word. Logical `%st' numbers are required for indexing ep->regs. */ st_regno = (fpreg + 8 - top) & 7; printf ("%%st(%d) %s ", st_regno, fpreg == top ? "=>" : " "); switch ((ep->tag >> (fpreg * 2)) & 3) { case 0: printf ("valid "); break; case 1: printf ("zero "); break; case 2: printf ("trap "); break; case 3: printf ("empty "); break; } for (i = 9; i >= 0; i--) printf ("%02x", ep->regs[st_regno][i]); i387_to_double (ep->regs[st_regno], (char *)&val); printf (" %g\n", val); } } void i386_float_info () { struct user u; /* just for address computations */ int i; /* fpstate defined in */ struct fpstate *fpstatep; char buf[sizeof (struct fpstate) + 2 * sizeof (int)]; unsigned int uaddr; char fpvalid; unsigned int rounded_addr; unsigned int rounded_size; /*extern int corechan;*/ int skip; extern int inferior_pid; uaddr = (char *)&U_FPSTATE(u) - (char *)&u; if (inferior_pid) { int *ip; rounded_addr = uaddr & -sizeof (int); rounded_size = (((uaddr + sizeof (struct fpstate)) - uaddr) + sizeof (int) - 1) / sizeof (int); skip = uaddr - rounded_addr; ip = (int *)buf; for (i = 0; i < rounded_size; i++) { *ip++ = ptrace (PT_READ_U, inferior_pid, (caddr_t)rounded_addr, 0); rounded_addr += sizeof (int); } } else { #if 1 printf("float info: can't do a core file (yet)\n"); return; #else if (lseek (corechan, uaddr, 0) < 0) perror_with_name ("seek on core file"); if (myread (corechan, buf, sizeof (struct fpstate)) < 0) perror_with_name ("read from core file"); skip = 0; #endif } fpstatep = (struct fpstate *)(buf + skip); print_387_status (fpstatep->sv_ex_sw, (struct env387 *)fpstatep); } #ifdef SETUP_ARBITRARY_FRAME FRAME setup_arbitrary_frame (numargs, args) int numargs; unsigned int *args; { if (numargs > 2) error ("Too many args in frame specification"); return create_new_frame ((CORE_ADDR)args[0], (CORE_ADDR)args[1]); } #endif #ifdef KERNEL_DEBUG #include #include #include #include #include #include #include #include #define KERNOFF ((unsigned)KERNBASE) #define INKERNEL(x) ((x) >= KERNOFF) static CORE_ADDR sbr; static CORE_ADDR curpcb; static CORE_ADDR kstack; static int found_pcb; static int devmem; static int kfd; static struct pcb pcb; int read_pcb (int, CORE_ADDR); static CORE_ADDR kvtophys (int, CORE_ADDR); static physrd(int, u_int, char*, int); extern CORE_ADDR ksym_lookup(const char *); /* substitutes for the stuff in libkvm which doesn't work */ /* most of this was taken from the old kgdb */ /* we don't need all this stuff, but the call should look the same */ kvm_open (efile, cfile, sfile, perm, errout) char *efile; char *cfile; char *sfile; /* makes this kvm_open more compatible to the one in libkvm */ int perm; char *errout; /* makes this kvm_open more compatible to the one in libkvm */ { struct stat stb; CORE_ADDR addr; int cfd; if ((cfd = open(cfile, perm, 0)) < 0) return (cfd); fstat(cfd, &stb); if ((stb.st_mode & S_IFMT) == S_IFCHR && stb.st_rdev == makedev(2, 0)) { devmem = 1; kfd = open ("/dev/kmem", perm, 0); } physrd(cfd, ksym_lookup("IdlePTD") - KERNOFF, (char*)&sbr, sizeof sbr); printf("IdlePTD %x\n", sbr); curpcb = ksym_lookup("curpcb") - KERNOFF; physrd(cfd, curpcb, (char*)&curpcb, sizeof curpcb); kstack = ksym_lookup("kstack"); found_pcb = 1; /* for vtophys */ if (!devmem) read_pcb(cfd, ksym_lookup("dumppcb") - KERNOFF); else read_pcb(cfd, kvtophys(cfd, kstack)); return (cfd); } kvm_close (fd) { return (close (fd)); } kvm_write(core_kd, memaddr, myaddr, len) CORE_ADDR memaddr; char *myaddr; { int cc; if (devmem) { if (kfd > 0) { /* * Just like kvm_read, only we write. */ errno = 0; if (lseek(kfd, (off_t)memaddr, 0) < 0 && errno != 0) { error("kvm_write:invalid address (%x)", memaddr); return (0); } cc = write(kfd, myaddr, len); if (cc < 0) { error("kvm_write:write failed"); return (0); } else if (cc < len) error("kvm_write:short write"); return (cc); } else return (0); } else { printf("kvm_write not implemented for dead kernels\n"); return (0); } /* NOTREACHED */ } kvm_read(core_kd, memaddr, myaddr, len) CORE_ADDR memaddr; char *myaddr; { return (kernel_core_file_hook (core_kd, memaddr, myaddr, len)); } kvm_uread(core_kd, p, memaddr, myaddr, len) register struct proc *p; CORE_ADDR memaddr; char *myaddr; { register char *cp; char procfile[MAXPATHLEN]; ssize_t amount; int fd; if (devmem) { cp = myaddr; sprintf(procfile, "/proc/%d/mem", p->p_pid); fd = open(procfile, O_RDONLY, 0); if (fd < 0) { error("cannot open %s", procfile); close(fd); return (0); } while (len > 0) { if (lseek(fd, memaddr, 0) == -1 && errno != 0) { error("invalid address (%x) in %s", memaddr, procfile); break; } amount = read(fd, cp, len); if (amount < 0) { error("error reading %s", procfile); break; } cp += amount; memaddr += amount; len -= amount; } close(fd); return (ssize_t)(cp - myaddr); } else { return (kernel_core_file_hook (core_kd, memaddr, myaddr, len)); } } static physrd(cfd, addr, dat, len) u_int addr; char *dat; { if (lseek(cfd, (off_t)addr, L_SET) == -1) return (-1); return (read(cfd, dat, len)); } static CORE_ADDR kvtophys (fd, addr) CORE_ADDR addr; { CORE_ADDR v; struct pte pte; static CORE_ADDR PTD = -1; CORE_ADDR current_ptd; /* * If we're looking at the kernel stack, * munge the address to refer to the user space mapping instead; * that way we get the requested process's kstack, not the running one. */ if (addr >= kstack && addr < kstack + ctob(UPAGES)) addr = (addr - kstack) + curpcb; /* * We may no longer have a linear system page table... * * Here's the scoop. IdlePTD contains the physical address * of a page table directory that always maps the kernel. * IdlePTD is in memory that is mapped 1-to-1, so we can * find it easily given its 'virtual' address from ksym_lookup(). * For hysterical reasons, the value of IdlePTD is stored in sbr. * * To look up a kernel address, we first convert it to a 1st-level * address and look it up in IdlePTD. This gives us the physical * address of a page table page; we extract the 2nd-level part of * VA and read the 2nd-level pte. Finally, we add the offset part * of the VA into the physical address from the pte and return it. * * User addresses are a little more complicated. If we don't have * a current PCB from read_pcb(), we use PTD, which is the (fixed) * virtual address of the current ptd. Since it's NOT in 1-to-1 * kernel space, we must look it up using IdlePTD. If we do have * a pcb, we get the ptd from pcb_ptd. */ if (INKERNEL(addr)) current_ptd = sbr; else if (found_pcb == 0) { if (PTD == -1) PTD = kvtophys(fd, ksym_lookup("PTD")); current_ptd = PTD; } else current_ptd = pcb.pcb_ptd; /* * Read the first-level page table (ptd). */ v = current_ptd + ((unsigned)addr >> PD_SHIFT) * sizeof pte; if (physrd(fd, v, (char *)&pte, sizeof pte) < 0 || pte.pg_v == 0) return (~0); /* * Read the second-level page table. */ v = i386_ptob(pte.pg_pfnum) + ((addr&PT_MASK) >> PG_SHIFT) * sizeof pte; if (physrd(fd, v, (char *) &pte, sizeof(pte)) < 0 || pte.pg_v == 0) return (~0); addr = i386_ptob(pte.pg_pfnum) + (addr & PGOFSET); #if 0 printf("vtophys(%x) -> %x\n", oldaddr, addr); #endif return (addr); } read_pcb (fd, uaddr) CORE_ADDR uaddr; { int i; int *pcb_regs = (int *)&pcb; int eip; if (physrd(fd, uaddr, (char *)&pcb, sizeof pcb) < 0) { error("cannot read pcb at %x\n", uaddr); return (-1); } printf("current pcb at %x\n", uaddr); /* * get the register values out of the sys pcb and * store them where `read_register' will find them. */ for (i = 0; i < 8; ++i) supply_register(i, &pcb_regs[i+10]); supply_register(8, &pcb_regs[8]); /* eip */ supply_register(9, &pcb_regs[9]); /* eflags */ for (i = 10; i < 13; ++i) /* cs, ss, ds */ supply_register(i, &pcb_regs[i+9]); supply_register(13, &pcb_regs[18]); /* es */ for (i = 14; i < 16; ++i) /* fs, gs */ supply_register(i, &pcb_regs[i+8]); #if 0 /* doesn't work ??? */ /* Hmm... */ if (target_read_memory(pcb_regs[5+10]+4, &eip, sizeof eip, 0)) error("Cannot read PC."); supply_register(8, &eip); /* eip */ #endif /* XXX 80387 registers? */ } /* * read len bytes from kernel virtual address 'addr' into local * buffer 'buf'. Return numbert of bytes if read ok, 0 otherwise. On read * errors, portion of buffer not read is zeroed. */ kernel_core_file_hook(fd, addr, buf, len) CORE_ADDR addr; char *buf; int len; { int i; CORE_ADDR paddr; register char *cp; int cc; cp = buf; while (len > 0) { paddr = kvtophys(fd, addr); if (paddr == ~0) { bzero(buf, len); break; } /* we can't read across a page boundary */ i = min(len, NBPG - (addr & PGOFSET)); if ((cc = physrd(fd, paddr, cp, i)) <= 0) { bzero(cp, len); return (cp - buf); } cp += cc; addr += cc; len -= cc; } return (cp - buf); } #endif /* KERNEL_DEBUG */