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Diffstat (limited to 'gdb/m68k-linux-nat.c')
| -rw-r--r-- | gdb/m68k-linux-nat.c | 542 |
1 files changed, 542 insertions, 0 deletions
diff --git a/gdb/m68k-linux-nat.c b/gdb/m68k-linux-nat.c new file mode 100644 index 0000000..5b8684b --- /dev/null +++ b/gdb/m68k-linux-nat.c @@ -0,0 +1,542 @@ +/* Motorola m68k native support for GNU/Linux. + + Copyright (C) 1996-2016 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 "regcache.h" +#include "target.h" +#include "linux-nat.h" + +#include "m68k-tdep.h" + +#include <sys/dir.h> +#include <signal.h> +#include "nat/gdb_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 <sys/stat.h> + +#include "floatformat.h" + +/* Prototypes for supply_gregset etc. */ +#include "gregset.h" + +/* Defines ps_err_e, struct ps_prochandle. */ +#include "gdb_proc_service.h" + +#ifndef PTRACE_GET_THREAD_AREA +#define PTRACE_GET_THREAD_AREA 25 +#endif + +/* 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) + +static int +getregs_supplies (int regno) +{ + return 0 <= regno && regno < NUM_GREGS; +} + +static int +getfpregs_supplies (int regno) +{ + return M68K_FP0_REGNUM <= regno && regno <= M68K_FPI_REGNUM; +} + +/* Does the current host support the GETREGS request? */ +static int have_ptrace_getregs = +#ifdef HAVE_PTRACE_GETREGS + 1 +#else + 0 +#endif +; + + + +/* Fetching registers directly from the U area, one at a time. */ + +/* Fetch one register. */ + +static void +fetch_register (struct regcache *regcache, int regno) +{ + struct gdbarch *gdbarch = get_regcache_arch (regcache); + long regaddr, val; + int i; + gdb_byte buf[MAX_REGISTER_SIZE]; + int tid; + + /* Overload thread id onto process id. */ + tid = ptid_get_lwp (inferior_ptid); + if (tid == 0) + tid = ptid_get_pid (inferior_ptid); /* no thread id, just use + process id. */ + + regaddr = 4 * regmap[regno]; + for (i = 0; i < register_size (gdbarch, regno); i += sizeof (long)) + { + errno = 0; + val = ptrace (PTRACE_PEEKUSER, tid, regaddr, 0); + memcpy (&buf[i], &val, sizeof (long)); + regaddr += sizeof (long); + if (errno != 0) + error (_("Couldn't read register %s (#%d): %s."), + gdbarch_register_name (gdbarch, regno), + regno, safe_strerror (errno)); + } + 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 = get_regcache_arch (regcache); + long regaddr, val; + int i; + int tid; + gdb_byte buf[MAX_REGISTER_SIZE]; + + /* Overload thread id onto process id. */ + tid = ptid_get_lwp (inferior_ptid); + if (tid == 0) + tid = ptid_get_pid (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 (long)) + { + errno = 0; + memcpy (&val, &buf[i], sizeof (long)); + ptrace (PTRACE_POKEUSER, tid, regaddr, val); + regaddr += sizeof (long); + if (errno != 0) + error (_("Couldn't write register %s (#%d): %s."), + gdbarch_register_name (gdbarch, regno), + regno, safe_strerror (errno)); + } +} + +/* 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, ®p[regmap[regi]]); + regcache_raw_supply (regcache, gdbarch_ps_regnum (gdbarch), + ®p[PT_SR]); + regcache_raw_supply (regcache, + gdbarch_pc_regnum (gdbarch), ®p[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) ®s) < 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 *) ®s); +} + +/* 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) ®s) < 0) + perror_with_name (_("Couldn't get registers")); + + fill_gregset (regcache, ®s, regno); + + if (ptrace (PTRACE_SETREGS, tid, 0, (int) ®s) < 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 target_ops *ops, + 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 = ptid_get_lwp (inferior_ptid); + if (tid == 0) + tid = ptid_get_pid (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 target_ops *ops, + 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 = ptid_get_lwp (inferior_ptid); + if (tid == 0) + tid = ptid_get_pid (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); +} + + +/* Fetch the thread-local storage pointer for libthread_db. */ + +ps_err_e +ps_get_thread_area (struct ps_prochandle *ph, + lwpid_t lwpid, int idx, void **base) +{ + if (ptrace (PTRACE_GET_THREAD_AREA, lwpid, NULL, base) < 0) + return PS_ERR; + + /* IDX is the bias from the thread pointer to the beginning of the + thread descriptor. It has to be subtracted due to implementation + quirks in libthread_db. */ + *base = (char *) *base - idx; + + return PS_OK; +} + + +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); +} |