binutils-gdb/gdb/m68klinux-nat.c

614 lines
16 KiB
C
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

/* Motorola m68k native support for GNU/Linux.
Copyright (C) 1996, 1998, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007
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 3 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, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "frame.h"
#include "inferior.h"
#include "language.h"
#include "gdbcore.h"
#include "gdb_string.h"
#include "regcache.h"
#include "target.h"
#include "linux-nat.h"
#include "m68k-tdep.h"
#include <sys/param.h>
#include <sys/dir.h>
#include <signal.h>
#include <sys/ptrace.h>
#include <sys/user.h>
#include <sys/ioctl.h>
#include <fcntl.h>
#include <sys/procfs.h>
#ifdef HAVE_SYS_REG_H
#include <sys/reg.h>
#endif
#include <sys/file.h>
#include "gdb_stat.h"
#include "floatformat.h"
#include "target.h"
/* Prototypes for supply_gregset etc. */
#include "gregset.h"
/* This table must line up with gdbarch_register_name in "m68k-tdep.c". */
static const int regmap[] =
{
PT_D0, PT_D1, PT_D2, PT_D3, PT_D4, PT_D5, PT_D6, PT_D7,
PT_A0, PT_A1, PT_A2, PT_A3, PT_A4, PT_A5, PT_A6, PT_USP,
PT_SR, PT_PC,
/* PT_FP0, ..., PT_FP7 */
21, 24, 27, 30, 33, 36, 39, 42,
/* PT_FPCR, PT_FPSR, PT_FPIAR */
45, 46, 47
};
/* Which ptrace request retrieves which registers?
These apply to the corresponding SET requests as well. */
#define NUM_GREGS (18)
#define MAX_NUM_REGS (NUM_GREGS + 11)
int
getregs_supplies (int regno)
{
return 0 <= regno && regno < NUM_GREGS;
}
int
getfpregs_supplies (int regno)
{
return gdbarch_fp0_regnum (current_gdbarch) <= regno
&& regno <= M68K_FPI_REGNUM;
}
/* Does the current host support the GETREGS request? */
int have_ptrace_getregs =
#ifdef HAVE_PTRACE_GETREGS
1
#else
0
#endif
;
/* Fetching registers directly from the U area, one at a time. */
/* FIXME: This duplicates code from `inptrace.c'. The problem is that we
define FETCH_INFERIOR_REGISTERS since we want to use our own versions
of {fetch,store}_inferior_registers that use the GETREGS request. This
means that the code in `infptrace.c' is #ifdef'd out. But we need to
fall back on that code when GDB is running on top of a kernel that
doesn't support the GETREGS request. */
#ifndef PT_READ_U
#define PT_READ_U PTRACE_PEEKUSR
#endif
#ifndef PT_WRITE_U
#define PT_WRITE_U PTRACE_POKEUSR
#endif
/* Fetch one register. */
static void
fetch_register (struct regcache *regcache, int regno)
{
struct gdbarch *gdbarch = get_regcache_arch (regcache);
/* This isn't really an address. But ptrace thinks of it as one. */
CORE_ADDR regaddr;
char mess[128]; /* For messages */
int i;
char buf[MAX_REGISTER_SIZE];
int tid;
if (gdbarch_cannot_fetch_register (gdbarch, regno))
{
memset (buf, '\0', register_size (gdbarch, regno)); /* Supply zeroes */
regcache_raw_supply (regcache, regno, buf);
return;
}
/* Overload thread id onto process id */
tid = TIDGET (inferior_ptid);
if (tid == 0)
tid = PIDGET (inferior_ptid); /* no thread id, just use process id */
regaddr = 4 * regmap[regno];
for (i = 0; i < register_size (gdbarch, regno);
i += sizeof (PTRACE_TYPE_RET))
{
errno = 0;
*(PTRACE_TYPE_RET *) &buf[i] = ptrace (PT_READ_U, tid,
(PTRACE_TYPE_ARG3) regaddr, 0);
regaddr += sizeof (PTRACE_TYPE_RET);
if (errno != 0)
{
sprintf (mess, "reading register %s (#%d)",
gdbarch_register_name (gdbarch, regno), regno);
perror_with_name (mess);
}
}
regcache_raw_supply (regcache, regno, buf);
}
/* Fetch register values from the inferior.
If REGNO is negative, do this for all registers.
Otherwise, REGNO specifies which register (so we can save time). */
static void
old_fetch_inferior_registers (struct regcache *regcache, int regno)
{
if (regno >= 0)
{
fetch_register (regcache, regno);
}
else
{
for (regno = 0;
regno < gdbarch_num_regs (get_regcache_arch (regcache));
regno++)
{
fetch_register (regcache, regno);
}
}
}
/* Store one register. */
static void
store_register (const struct regcache *regcache, int regno)
{
struct gdbarch *gdbarch = reg_regcache_arch (regcache);
/* This isn't really an address. But ptrace thinks of it as one. */
CORE_ADDR regaddr;
char mess[128]; /* For messages */
int i;
int tid;
char buf[MAX_REGISTER_SIZE];
if (gdbarch_cannot_store_register (gdbarch, regno))
return;
/* Overload thread id onto process id */
tid = TIDGET (inferior_ptid);
if (tid == 0)
tid = PIDGET (inferior_ptid); /* no thread id, just use process id */
regaddr = 4 * regmap[regno];
/* Put the contents of regno into a local buffer */
regcache_raw_collect (regcache, regno, buf);
/* Store the local buffer into the inferior a chunk at the time. */
for (i = 0; i < register_size (gdbarch, regno);
i += sizeof (PTRACE_TYPE_RET))
{
errno = 0;
ptrace (PT_WRITE_U, tid, (PTRACE_TYPE_ARG3) regaddr,
*(PTRACE_TYPE_RET *) (buf + i));
regaddr += sizeof (PTRACE_TYPE_RET);
if (errno != 0)
{
sprintf (mess, "writing register %s (#%d)",
gdbarch_register_name (gdbarch, regno), regno);
perror_with_name (mess);
}
}
}
/* Store our register values back into the inferior.
If REGNO is negative, do this for all registers.
Otherwise, REGNO specifies which register (so we can save time). */
static void
old_store_inferior_registers (const struct regcache *regcache, int regno)
{
if (regno >= 0)
{
store_register (regcache, regno);
}
else
{
for (regno = 0;
regno < gdbarch_num_regs (get_regcache_arch (regcache));
regno++)
{
store_register (regcache, regno);
}
}
}
/* Given a pointer to a general register set in /proc format
(elf_gregset_t *), unpack the register contents and supply
them as gdb's idea of the current register values. */
void
supply_gregset (struct regcache *regcache, const elf_gregset_t *gregsetp)
{
struct gdbarch *gdbarch = get_regcache_arch (regcache);
const elf_greg_t *regp = (const elf_greg_t *) gregsetp;
int regi;
for (regi = M68K_D0_REGNUM;
regi <= gdbarch_sp_regnum (gdbarch);
regi++)
regcache_raw_supply (regcache, regi, &regp[regmap[regi]]);
regcache_raw_supply (regcache, gdbarch_ps_regnum (gdbarch),
&regp[PT_SR]);
regcache_raw_supply (regcache,
gdbarch_pc_regnum (gdbarch), &regp[PT_PC]);
}
/* Fill register REGNO (if it is a general-purpose register) in
*GREGSETPS with the value in GDB's register array. If REGNO is -1,
do this for all registers. */
void
fill_gregset (const struct regcache *regcache,
elf_gregset_t *gregsetp, int regno)
{
elf_greg_t *regp = (elf_greg_t *) gregsetp;
int i;
for (i = 0; i < NUM_GREGS; i++)
if (regno == -1 || regno == i)
regcache_raw_collect (regcache, i, regp + regmap[i]);
}
#ifdef HAVE_PTRACE_GETREGS
/* Fetch all general-purpose registers from process/thread TID and
store their values in GDB's register array. */
static void
fetch_regs (struct regcache *regcache, int tid)
{
elf_gregset_t regs;
if (ptrace (PTRACE_GETREGS, tid, 0, (int) &regs) < 0)
{
if (errno == EIO)
{
/* The kernel we're running on doesn't support the GETREGS
request. Reset `have_ptrace_getregs'. */
have_ptrace_getregs = 0;
return;
}
perror_with_name (_("Couldn't get registers"));
}
supply_gregset (regcache, (const elf_gregset_t *) &regs);
}
/* Store all valid general-purpose registers in GDB's register array
into the process/thread specified by TID. */
static void
store_regs (const struct regcache *regcache, int tid, int regno)
{
elf_gregset_t regs;
if (ptrace (PTRACE_GETREGS, tid, 0, (int) &regs) < 0)
perror_with_name (_("Couldn't get registers"));
fill_gregset (regcache, &regs, regno);
if (ptrace (PTRACE_SETREGS, tid, 0, (int) &regs) < 0)
perror_with_name (_("Couldn't write registers"));
}
#else
static void fetch_regs (struct regcache *regcache, int tid) {}
static void store_regs (const struct regcache *regcache, int tid, int regno) {}
#endif
/* Transfering floating-point registers between GDB, inferiors and cores. */
/* What is the address of fpN within the floating-point register set F? */
#define FPREG_ADDR(f, n) (&(f)->fpregs[(n) * 3])
/* Fill GDB's register array with the floating-point register values in
*FPREGSETP. */
void
supply_fpregset (struct regcache *regcache, const elf_fpregset_t *fpregsetp)
{
struct gdbarch *gdbarch = get_regcache_arch (regcache);
int regi;
for (regi = gdbarch_fp0_regnum (gdbarch);
regi < gdbarch_fp0_regnum (gdbarch) + 8; regi++)
regcache_raw_supply (regcache, regi,
FPREG_ADDR (fpregsetp,
regi - gdbarch_fp0_regnum (gdbarch)));
regcache_raw_supply (regcache, M68K_FPC_REGNUM, &fpregsetp->fpcntl[0]);
regcache_raw_supply (regcache, M68K_FPS_REGNUM, &fpregsetp->fpcntl[1]);
regcache_raw_supply (regcache, M68K_FPI_REGNUM, &fpregsetp->fpcntl[2]);
}
/* Fill register REGNO (if it is a floating-point register) in
*FPREGSETP with the value in GDB's register array. If REGNO is -1,
do this for all registers. */
void
fill_fpregset (const struct regcache *regcache,
elf_fpregset_t *fpregsetp, int regno)
{
struct gdbarch *gdbarch = get_regcache_arch (regcache);
int i;
/* Fill in the floating-point registers. */
for (i = gdbarch_fp0_regnum (gdbarch);
i < gdbarch_fp0_regnum (gdbarch) + 8; i++)
if (regno == -1 || regno == i)
regcache_raw_collect (regcache, i,
FPREG_ADDR (fpregsetp,
i - gdbarch_fp0_regnum (gdbarch)));
/* Fill in the floating-point control registers. */
for (i = M68K_FPC_REGNUM; i <= M68K_FPI_REGNUM; i++)
if (regno == -1 || regno == i)
regcache_raw_collect (regcache, i,
&fpregsetp->fpcntl[i - M68K_FPC_REGNUM]);
}
#ifdef HAVE_PTRACE_GETREGS
/* Fetch all floating-point registers from process/thread TID and store
thier values in GDB's register array. */
static void
fetch_fpregs (struct regcache *regcache, int tid)
{
elf_fpregset_t fpregs;
if (ptrace (PTRACE_GETFPREGS, tid, 0, (int) &fpregs) < 0)
perror_with_name (_("Couldn't get floating point status"));
supply_fpregset (regcache, (const elf_fpregset_t *) &fpregs);
}
/* Store all valid floating-point registers in GDB's register array
into the process/thread specified by TID. */
static void
store_fpregs (const struct regcache *regcache, int tid, int regno)
{
elf_fpregset_t fpregs;
if (ptrace (PTRACE_GETFPREGS, tid, 0, (int) &fpregs) < 0)
perror_with_name (_("Couldn't get floating point status"));
fill_fpregset (regcache, &fpregs, regno);
if (ptrace (PTRACE_SETFPREGS, tid, 0, (int) &fpregs) < 0)
perror_with_name (_("Couldn't write floating point status"));
}
#else
static void fetch_fpregs (struct regcache *regcache, int tid) {}
static void store_fpregs (const struct regcache *regcache, int tid, int regno) {}
#endif
/* Transferring arbitrary registers between GDB and inferior. */
/* Fetch register REGNO from the child process. If REGNO is -1, do
this for all registers (including the floating point and SSE
registers). */
static void
m68k_linux_fetch_inferior_registers (struct regcache *regcache, int regno)
{
int tid;
/* Use the old method of peeking around in `struct user' if the
GETREGS request isn't available. */
if (! have_ptrace_getregs)
{
old_fetch_inferior_registers (regcache, regno);
return;
}
/* GNU/Linux LWP ID's are process ID's. */
tid = TIDGET (inferior_ptid);
if (tid == 0)
tid = PIDGET (inferior_ptid); /* Not a threaded program. */
/* Use the PTRACE_GETFPXREGS request whenever possible, since it
transfers more registers in one system call, and we'll cache the
results. But remember that fetch_fpxregs can fail, and return
zero. */
if (regno == -1)
{
fetch_regs (regcache, tid);
/* The call above might reset `have_ptrace_getregs'. */
if (! have_ptrace_getregs)
{
old_fetch_inferior_registers (regcache, -1);
return;
}
fetch_fpregs (regcache, tid);
return;
}
if (getregs_supplies (regno))
{
fetch_regs (regcache, tid);
return;
}
if (getfpregs_supplies (regno))
{
fetch_fpregs (regcache, tid);
return;
}
internal_error (__FILE__, __LINE__,
_("Got request for bad register number %d."), regno);
}
/* Store register REGNO back into the child process. If REGNO is -1,
do this for all registers (including the floating point and SSE
registers). */
static void
m68k_linux_store_inferior_registers (struct regcache *regcache, int regno)
{
int tid;
/* Use the old method of poking around in `struct user' if the
SETREGS request isn't available. */
if (! have_ptrace_getregs)
{
old_store_inferior_registers (regcache, regno);
return;
}
/* GNU/Linux LWP ID's are process ID's. */
tid = TIDGET (inferior_ptid);
if (tid == 0)
tid = PIDGET (inferior_ptid); /* Not a threaded program. */
/* Use the PTRACE_SETFPREGS requests whenever possible, since it
transfers more registers in one system call. But remember that
store_fpregs can fail, and return zero. */
if (regno == -1)
{
store_regs (regcache, tid, regno);
store_fpregs (regcache, tid, regno);
return;
}
if (getregs_supplies (regno))
{
store_regs (regcache, tid, regno);
return;
}
if (getfpregs_supplies (regno))
{
store_fpregs (regcache, tid, regno);
return;
}
internal_error (__FILE__, __LINE__,
_("Got request to store bad register number %d."), regno);
}
/* Interpreting register set info found in core files. */
/* Provide registers to GDB from a core file.
(We can't use the generic version of this function in
core-regset.c, because we need to use elf_gregset_t instead of
gregset_t.)
CORE_REG_SECT points to an array of bytes, which are the contents
of a `note' from a core file which BFD thinks might contain
register contents. CORE_REG_SIZE is its size.
WHICH says which register set corelow suspects this is:
0 --- the general-purpose register set, in elf_gregset_t format
2 --- the floating-point register set, in elf_fpregset_t format
REG_ADDR isn't used on GNU/Linux. */
static void
fetch_core_registers (struct regcache *regcache,
char *core_reg_sect, unsigned core_reg_size,
int which, CORE_ADDR reg_addr)
{
elf_gregset_t gregset;
elf_fpregset_t fpregset;
switch (which)
{
case 0:
if (core_reg_size != sizeof (gregset))
warning (_("Wrong size gregset in core file."));
else
{
memcpy (&gregset, core_reg_sect, sizeof (gregset));
supply_gregset (regcache, (const elf_gregset_t *) &gregset);
}
break;
case 2:
if (core_reg_size != sizeof (fpregset))
warning (_("Wrong size fpregset in core file."));
else
{
memcpy (&fpregset, core_reg_sect, sizeof (fpregset));
supply_fpregset (regcache, (const elf_fpregset_t *) &fpregset);
}
break;
default:
/* We've covered all the kinds of registers we know about here,
so this must be something we wouldn't know what to do with
anyway. Just ignore it. */
break;
}
}
/* Register that we are able to handle GNU/Linux ELF core file
formats. */
static struct core_fns linux_elf_core_fns =
{
bfd_target_elf_flavour, /* core_flavour */
default_check_format, /* check_format */
default_core_sniffer, /* core_sniffer */
fetch_core_registers, /* core_read_registers */
NULL /* next */
};
void _initialize_m68k_linux_nat (void);
void
_initialize_m68k_linux_nat (void)
{
struct target_ops *t;
/* Fill in the generic GNU/Linux methods. */
t = linux_target ();
/* Add our register access methods. */
t->to_fetch_registers = m68k_linux_fetch_inferior_registers;
t->to_store_registers = m68k_linux_store_inferior_registers;
/* Register the target. */
linux_nat_add_target (t);
deprecated_add_core_fns (&linux_elf_core_fns);
}