binutils-gdb/gdb/s390-nat.c

419 lines
12 KiB
C

/* S390 native-dependent code for GDB, the GNU debugger.
Copyright (C) 2001, 2003, 2004, 2005, 2006, 2007, 2009
Free Software Foundation, Inc
Contributed by D.J. Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com)
for IBM Deutschland Entwicklung GmbH, IBM Corporation.
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 "regcache.h"
#include "inferior.h"
#include "target.h"
#include "linux-nat.h"
#include "s390-tdep.h"
#include <asm/ptrace.h>
#include <sys/ptrace.h>
#include <asm/types.h>
#include <sys/procfs.h>
#include <sys/ucontext.h>
/* Map registers to gregset/ptrace offsets.
These arrays are defined in s390-tdep.c. */
#ifdef __s390x__
#define regmap_gregset s390x_regmap_gregset
#else
#define regmap_gregset s390_regmap_gregset
#endif
#define regmap_fpregset s390_regmap_fpregset
/* When debugging a 32-bit executable running under a 64-bit kernel,
we have to fix up the 64-bit registers we get from the kernel
to make them look like 32-bit registers. */
#ifdef __s390x__
#define SUBOFF(gdbarch, i) \
((gdbarch_ptr_bit (gdbarch) == 32 \
&& ((i) == S390_PSWA_REGNUM \
|| ((i) >= S390_R0_REGNUM && (i) <= S390_R15_REGNUM)))? 4 : 0)
#else
#define SUBOFF(gdbarch, i) 0
#endif
/* Fill GDB's register array with the general-purpose register values
in *REGP. */
void
supply_gregset (struct regcache *regcache, const gregset_t *regp)
{
struct gdbarch *gdbarch = get_regcache_arch (regcache);
int i;
for (i = 0; i < S390_NUM_REGS; i++)
if (regmap_gregset[i] != -1)
regcache_raw_supply (regcache, i,
(const char *)regp + regmap_gregset[i]
+ SUBOFF (gdbarch, i));
}
/* Fill register REGNO (if it is a general-purpose register) in
*REGP with the value in GDB's register array. If REGNO is -1,
do this for all registers. */
void
fill_gregset (const struct regcache *regcache, gregset_t *regp, int regno)
{
struct gdbarch *gdbarch = get_regcache_arch (regcache);
int i;
for (i = 0; i < S390_NUM_REGS; i++)
if (regmap_gregset[i] != -1)
if (regno == -1 || regno == i)
regcache_raw_collect (regcache, i,
(char *)regp + regmap_gregset[i]
+ SUBOFF (gdbarch, i));
}
/* Fill GDB's register array with the floating-point register values
in *REGP. */
void
supply_fpregset (struct regcache *regcache, const fpregset_t *regp)
{
int i;
for (i = 0; i < S390_NUM_REGS; i++)
if (regmap_fpregset[i] != -1)
regcache_raw_supply (regcache, i,
(const char *)regp + regmap_fpregset[i]);
}
/* Fill register REGNO (if it is a general-purpose register) in
*REGP with the value in GDB's register array. If REGNO is -1,
do this for all registers. */
void
fill_fpregset (const struct regcache *regcache, fpregset_t *regp, int regno)
{
int i;
for (i = 0; i < S390_NUM_REGS; i++)
if (regmap_fpregset[i] != -1)
if (regno == -1 || regno == i)
regcache_raw_collect (regcache, i,
(char *)regp + regmap_fpregset[i]);
}
/* Find the TID for the current inferior thread to use with ptrace. */
static int
s390_inferior_tid (void)
{
/* GNU/Linux LWP ID's are process ID's. */
int tid = TIDGET (inferior_ptid);
if (tid == 0)
tid = PIDGET (inferior_ptid); /* Not a threaded program. */
return tid;
}
/* Fetch all general-purpose registers from process/thread TID and
store their values in GDB's register cache. */
static void
fetch_regs (struct regcache *regcache, int tid)
{
gregset_t regs;
ptrace_area parea;
parea.len = sizeof (regs);
parea.process_addr = (addr_t) &regs;
parea.kernel_addr = offsetof (struct user_regs_struct, psw);
if (ptrace (PTRACE_PEEKUSR_AREA, tid, (long) &parea) < 0)
perror_with_name (_("Couldn't get registers"));
supply_gregset (regcache, (const gregset_t *) &regs);
}
/* Store all valid general-purpose registers in GDB's register cache
into the process/thread specified by TID. */
static void
store_regs (const struct regcache *regcache, int tid, int regnum)
{
gregset_t regs;
ptrace_area parea;
parea.len = sizeof (regs);
parea.process_addr = (addr_t) &regs;
parea.kernel_addr = offsetof (struct user_regs_struct, psw);
if (ptrace (PTRACE_PEEKUSR_AREA, tid, (long) &parea) < 0)
perror_with_name (_("Couldn't get registers"));
fill_gregset (regcache, &regs, regnum);
if (ptrace (PTRACE_POKEUSR_AREA, tid, (long) &parea) < 0)
perror_with_name (_("Couldn't write registers"));
}
/* Fetch all floating-point registers from process/thread TID and store
their values in GDB's register cache. */
static void
fetch_fpregs (struct regcache *regcache, int tid)
{
fpregset_t fpregs;
ptrace_area parea;
parea.len = sizeof (fpregs);
parea.process_addr = (addr_t) &fpregs;
parea.kernel_addr = offsetof (struct user_regs_struct, fp_regs);
if (ptrace (PTRACE_PEEKUSR_AREA, tid, (long) &parea) < 0)
perror_with_name (_("Couldn't get floating point status"));
supply_fpregset (regcache, (const fpregset_t *) &fpregs);
}
/* Store all valid floating-point registers in GDB's register cache
into the process/thread specified by TID. */
static void
store_fpregs (const struct regcache *regcache, int tid, int regnum)
{
fpregset_t fpregs;
ptrace_area parea;
parea.len = sizeof (fpregs);
parea.process_addr = (addr_t) &fpregs;
parea.kernel_addr = offsetof (struct user_regs_struct, fp_regs);
if (ptrace (PTRACE_PEEKUSR_AREA, tid, (long) &parea) < 0)
perror_with_name (_("Couldn't get floating point status"));
fill_fpregset (regcache, &fpregs, regnum);
if (ptrace (PTRACE_POKEUSR_AREA, tid, (long) &parea) < 0)
perror_with_name (_("Couldn't write floating point status"));
}
/* Fetch register REGNUM from the child process. If REGNUM is -1, do
this for all registers. */
static void
s390_linux_fetch_inferior_registers (struct target_ops *ops,
struct regcache *regcache, int regnum)
{
int tid = s390_inferior_tid ();
if (regnum == -1
|| (regnum < S390_NUM_REGS && regmap_gregset[regnum] != -1))
fetch_regs (regcache, tid);
if (regnum == -1
|| (regnum < S390_NUM_REGS && regmap_fpregset[regnum] != -1))
fetch_fpregs (regcache, tid);
}
/* Store register REGNUM back into the child process. If REGNUM is
-1, do this for all registers. */
static void
s390_linux_store_inferior_registers (struct target_ops *ops,
struct regcache *regcache, int regnum)
{
int tid = s390_inferior_tid ();
if (regnum == -1
|| (regnum < S390_NUM_REGS && regmap_gregset[regnum] != -1))
store_regs (regcache, tid, regnum);
if (regnum == -1
|| (regnum < S390_NUM_REGS && regmap_fpregset[regnum] != -1))
store_fpregs (regcache, tid, regnum);
}
/* Hardware-assisted watchpoint handling. */
/* We maintain a list of all currently active watchpoints in order
to properly handle watchpoint removal.
The only thing we actually need is the total address space area
spanned by the watchpoints. */
struct watch_area
{
struct watch_area *next;
CORE_ADDR lo_addr;
CORE_ADDR hi_addr;
};
static struct watch_area *watch_base = NULL;
static int
s390_stopped_by_watchpoint (void)
{
per_lowcore_bits per_lowcore;
ptrace_area parea;
int result;
/* Speed up common case. */
if (!watch_base)
return 0;
parea.len = sizeof (per_lowcore);
parea.process_addr = (addr_t) & per_lowcore;
parea.kernel_addr = offsetof (struct user_regs_struct, per_info.lowcore);
if (ptrace (PTRACE_PEEKUSR_AREA, s390_inferior_tid (), &parea) < 0)
perror_with_name (_("Couldn't retrieve watchpoint status"));
result = (per_lowcore.perc_storage_alteration == 1
&& per_lowcore.perc_store_real_address == 0);
if (result)
{
/* Do not report this watchpoint again. */
memset (&per_lowcore, 0, sizeof (per_lowcore));
if (ptrace (PTRACE_POKEUSR_AREA, s390_inferior_tid (), &parea) < 0)
perror_with_name (_("Couldn't clear watchpoint status"));
}
return result;
}
static void
s390_fix_watch_points (ptid_t ptid)
{
int tid;
per_struct per_info;
ptrace_area parea;
CORE_ADDR watch_lo_addr = (CORE_ADDR)-1, watch_hi_addr = 0;
struct watch_area *area;
tid = TIDGET (ptid);
if (tid == 0)
tid = PIDGET (ptid);
for (area = watch_base; area; area = area->next)
{
watch_lo_addr = min (watch_lo_addr, area->lo_addr);
watch_hi_addr = max (watch_hi_addr, area->hi_addr);
}
parea.len = sizeof (per_info);
parea.process_addr = (addr_t) & per_info;
parea.kernel_addr = offsetof (struct user_regs_struct, per_info);
if (ptrace (PTRACE_PEEKUSR_AREA, tid, &parea) < 0)
perror_with_name (_("Couldn't retrieve watchpoint status"));
if (watch_base)
{
per_info.control_regs.bits.em_storage_alteration = 1;
per_info.control_regs.bits.storage_alt_space_ctl = 1;
}
else
{
per_info.control_regs.bits.em_storage_alteration = 0;
per_info.control_regs.bits.storage_alt_space_ctl = 0;
}
per_info.starting_addr = watch_lo_addr;
per_info.ending_addr = watch_hi_addr;
if (ptrace (PTRACE_POKEUSR_AREA, tid, &parea) < 0)
perror_with_name (_("Couldn't modify watchpoint status"));
}
static int
s390_insert_watchpoint (CORE_ADDR addr, int len, int type)
{
struct lwp_info *lp;
ptid_t ptid;
struct watch_area *area = xmalloc (sizeof (struct watch_area));
if (!area)
return -1;
area->lo_addr = addr;
area->hi_addr = addr + len - 1;
area->next = watch_base;
watch_base = area;
ALL_LWPS (lp, ptid)
s390_fix_watch_points (ptid);
return 0;
}
static int
s390_remove_watchpoint (CORE_ADDR addr, int len, int type)
{
struct lwp_info *lp;
ptid_t ptid;
struct watch_area *area, **parea;
for (parea = &watch_base; *parea; parea = &(*parea)->next)
if ((*parea)->lo_addr == addr
&& (*parea)->hi_addr == addr + len - 1)
break;
if (!*parea)
{
fprintf_unfiltered (gdb_stderr,
"Attempt to remove nonexistent watchpoint.\n");
return -1;
}
area = *parea;
*parea = area->next;
xfree (area);
ALL_LWPS (lp, ptid)
s390_fix_watch_points (ptid);
return 0;
}
static int
s390_can_use_hw_breakpoint (int type, int cnt, int othertype)
{
return type == bp_hardware_watchpoint;
}
static int
s390_region_ok_for_hw_watchpoint (CORE_ADDR addr, int cnt)
{
return 1;
}
void _initialize_s390_nat (void);
void
_initialize_s390_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 = s390_linux_fetch_inferior_registers;
t->to_store_registers = s390_linux_store_inferior_registers;
/* Add our watchpoint methods. */
t->to_can_use_hw_breakpoint = s390_can_use_hw_breakpoint;
t->to_region_ok_for_hw_watchpoint = s390_region_ok_for_hw_watchpoint;
t->to_have_continuable_watchpoint = 1;
t->to_stopped_by_watchpoint = s390_stopped_by_watchpoint;
t->to_insert_watchpoint = s390_insert_watchpoint;
t->to_remove_watchpoint = s390_remove_watchpoint;
/* Register the target. */
linux_nat_add_target (t);
linux_nat_set_new_thread (t, s390_fix_watch_points);
}