| /* Motorola m68k native support for GNU/Linux. | 
 |  | 
 |    Copyright (C) 1996-2022 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 (__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).  */ | 
 | 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 (__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 | 
 | _initialize_m68k_linux_nat () | 
 | { | 
 |   /* Register the target.  */ | 
 |   linux_target = &the_m68k_linux_nat_target; | 
 |   add_inf_child_target (&the_m68k_linux_nat_target); | 
 | } |