| /* Motorola m68k native support for GNU/Linux. |
| |
| Copyright (C) 1996-2023 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 "gdbarch.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" |
| |
| #include "inf-ptrace.h" |
| |
| #ifndef PTRACE_GET_THREAD_AREA |
| #define PTRACE_GET_THREAD_AREA 25 |
| #endif |
| |
| |
| class m68k_linux_nat_target final : public linux_nat_target |
| { |
| public: |
| /* Add our register access methods. */ |
| void fetch_registers (struct regcache *, int) override; |
| void store_registers (struct regcache *, int) override; |
| }; |
| |
| static m68k_linux_nat_target the_m68k_linux_nat_target; |
| |
| /* 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 = regcache->arch (); |
| long regaddr, val; |
| int i; |
| gdb_byte buf[M68K_MAX_REGISTER_SIZE]; |
| pid_t tid = get_ptrace_pid (regcache->ptid ()); |
| |
| 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 (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 (regcache->arch ()); |
| regno++) |
| { |
| fetch_register (regcache, regno); |
| } |
| } |
| } |
| |
| /* Store one register. */ |
| |
| static void |
| store_register (const struct regcache *regcache, int regno) |
| { |
| struct gdbarch *gdbarch = regcache->arch (); |
| long regaddr, val; |
| int i; |
| gdb_byte buf[M68K_MAX_REGISTER_SIZE]; |
| pid_t tid = get_ptrace_pid (regcache->ptid ()); |
| |
| regaddr = 4 * regmap[regno]; |
| |
| /* Put the contents of regno into a local buffer. */ |
| regcache->raw_collect (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 (regcache->arch ()); |
| 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 = regcache->arch (); |
| 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 (regi, ®p[regmap[regi]]); |
| regcache->raw_supply (gdbarch_ps_regnum (gdbarch), ®p[PT_SR]); |
| regcache->raw_supply (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 (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 = regcache->arch (); |
| int regi; |
| |
| for (regi = gdbarch_fp0_regnum (gdbarch); |
| regi < gdbarch_fp0_regnum (gdbarch) + 8; regi++) |
| regcache->raw_supply |
| (regi, FPREG_ADDR (fpregsetp, regi - gdbarch_fp0_regnum (gdbarch))); |
| regcache->raw_supply (M68K_FPC_REGNUM, &fpregsetp->fpcntl[0]); |
| regcache->raw_supply (M68K_FPS_REGNUM, &fpregsetp->fpcntl[1]); |
| regcache->raw_supply (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 = regcache->arch (); |
| 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 |
| (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 (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). */ |
| |
| void |
| m68k_linux_nat_target::fetch_registers (struct regcache *regcache, int regno) |
| { |
| pid_t 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; |
| } |
| |
| tid = get_ptrace_pid (regcache->ptid ()); |
| |
| /* 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 (_("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). */ |
| void |
| m68k_linux_nat_target::store_registers (struct regcache *regcache, int regno) |
| { |
| pid_t 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; |
| } |
| |
| tid = get_ptrace_pid (regcache->ptid ()); |
| |
| /* 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 (_("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 |
| _initialize_m68k_linux_nat () |
| { |
| /* Register the target. */ |
| linux_target = &the_m68k_linux_nat_target; |
| add_inf_child_target (&the_m68k_linux_nat_target); |
| } |
