| /* GNU/Linux/PowerPC specific low level interface, for the in-process |
| agent library for GDB. |
| |
| Copyright (C) 2016-2021 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 "server.h" |
| #include <sys/mman.h> |
| #include "tracepoint.h" |
| #include "arch/ppc-linux-tdesc.h" |
| #include "linux-ppc-tdesc-init.h" |
| #include <elf.h> |
| #ifdef HAVE_GETAUXVAL |
| #include <sys/auxv.h> |
| #endif |
| |
| /* These macros define the position of registers in the buffer collected |
| by the fast tracepoint jump pad. */ |
| #define FT_CR_R0 0 |
| #define FT_CR_CR 32 |
| #define FT_CR_XER 33 |
| #define FT_CR_LR 34 |
| #define FT_CR_CTR 35 |
| #define FT_CR_PC 36 |
| #define FT_CR_GPR(n) (FT_CR_R0 + (n)) |
| |
| static const int ppc_ft_collect_regmap[] = { |
| /* GPRs */ |
| FT_CR_GPR (0), FT_CR_GPR (1), FT_CR_GPR (2), |
| FT_CR_GPR (3), FT_CR_GPR (4), FT_CR_GPR (5), |
| FT_CR_GPR (6), FT_CR_GPR (7), FT_CR_GPR (8), |
| FT_CR_GPR (9), FT_CR_GPR (10), FT_CR_GPR (11), |
| FT_CR_GPR (12), FT_CR_GPR (13), FT_CR_GPR (14), |
| FT_CR_GPR (15), FT_CR_GPR (16), FT_CR_GPR (17), |
| FT_CR_GPR (18), FT_CR_GPR (19), FT_CR_GPR (20), |
| FT_CR_GPR (21), FT_CR_GPR (22), FT_CR_GPR (23), |
| FT_CR_GPR (24), FT_CR_GPR (25), FT_CR_GPR (26), |
| FT_CR_GPR (27), FT_CR_GPR (28), FT_CR_GPR (29), |
| FT_CR_GPR (30), FT_CR_GPR (31), |
| /* FPRs - not collected. */ |
| -1, -1, -1, -1, -1, -1, -1, -1, |
| -1, -1, -1, -1, -1, -1, -1, -1, |
| -1, -1, -1, -1, -1, -1, -1, -1, |
| -1, -1, -1, -1, -1, -1, -1, -1, |
| FT_CR_PC, /* PC */ |
| -1, /* MSR */ |
| FT_CR_CR, /* CR */ |
| FT_CR_LR, /* LR */ |
| FT_CR_CTR, /* CTR */ |
| FT_CR_XER, /* XER */ |
| -1, /* FPSCR */ |
| }; |
| |
| #define PPC_NUM_FT_COLLECT_GREGS \ |
| (sizeof (ppc_ft_collect_regmap) / sizeof(ppc_ft_collect_regmap[0])) |
| |
| /* Supply registers collected by the fast tracepoint jump pad. |
| BUF is the second argument we pass to gdb_collect in jump pad. */ |
| |
| void |
| supply_fast_tracepoint_registers (struct regcache *regcache, |
| const unsigned char *buf) |
| { |
| int i; |
| |
| for (i = 0; i < PPC_NUM_FT_COLLECT_GREGS; i++) |
| { |
| if (ppc_ft_collect_regmap[i] == -1) |
| continue; |
| supply_register (regcache, i, |
| ((char *) buf) |
| + ppc_ft_collect_regmap[i] * sizeof (long)); |
| } |
| } |
| |
| /* Return the value of register REGNUM. RAW_REGS is collected buffer |
| by jump pad. This function is called by emit_reg. */ |
| |
| ULONGEST |
| get_raw_reg (const unsigned char *raw_regs, int regnum) |
| { |
| if (regnum >= PPC_NUM_FT_COLLECT_GREGS) |
| return 0; |
| if (ppc_ft_collect_regmap[regnum] == -1) |
| return 0; |
| |
| return *(unsigned long *) (raw_regs |
| + ppc_ft_collect_regmap[regnum] * sizeof (long)); |
| } |
| |
| /* Allocate buffer for the jump pads. The branch instruction has a reach |
| of +/- 32MiB, and the executable is loaded at 0x10000000 (256MiB). |
| |
| 64-bit: To maximize the area of executable that can use tracepoints, |
| try allocating at 0x10000000 - size initially, decreasing until we hit |
| a free area. |
| |
| 32-bit: ld.so loads dynamic libraries right below the executable, so |
| we cannot depend on that area (dynamic libraries can be quite large). |
| Instead, aim right after the executable - at sbrk(0). This will |
| cause future brk to fail, and malloc will fallback to mmap. */ |
| |
| void * |
| alloc_jump_pad_buffer (size_t size) |
| { |
| #ifdef __powerpc64__ |
| uintptr_t addr; |
| uintptr_t exec_base = getauxval (AT_PHDR); |
| int pagesize; |
| void *res; |
| |
| if (exec_base == 0) |
| exec_base = 0x10000000; |
| |
| pagesize = sysconf (_SC_PAGE_SIZE); |
| if (pagesize == -1) |
| perror_with_name ("sysconf"); |
| |
| addr = exec_base - size; |
| |
| /* size should already be page-aligned, but this can't hurt. */ |
| addr &= ~(pagesize - 1); |
| |
| /* Search for a free area. If we hit 0, we're out of luck. */ |
| for (; addr; addr -= pagesize) |
| { |
| /* No MAP_FIXED - we don't want to zap someone's mapping. */ |
| res = mmap ((void *) addr, size, |
| PROT_READ | PROT_WRITE | PROT_EXEC, |
| MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); |
| |
| /* If we got what we wanted, return. */ |
| if ((uintptr_t) res == addr) |
| return res; |
| |
| /* If we got a mapping, but at a wrong address, undo it. */ |
| if (res != MAP_FAILED) |
| munmap (res, size); |
| } |
| |
| return NULL; |
| #else |
| void *target = sbrk (0); |
| void *res = mmap (target, size, PROT_READ | PROT_WRITE | PROT_EXEC, |
| MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); |
| |
| if (res == target) |
| return res; |
| |
| if (res != MAP_FAILED) |
| munmap (res, size); |
| |
| return NULL; |
| #endif |
| } |
| |
| /* Return target_desc to use for IPA, given the tdesc index passed by |
| gdbserver. */ |
| |
| const struct target_desc * |
| get_ipa_tdesc (int idx) |
| { |
| switch (idx) |
| { |
| #ifdef __powerpc64__ |
| case PPC_TDESC_BASE: |
| return tdesc_powerpc_64l; |
| case PPC_TDESC_ALTIVEC: |
| return tdesc_powerpc_altivec64l; |
| case PPC_TDESC_VSX: |
| return tdesc_powerpc_vsx64l; |
| case PPC_TDESC_ISA205: |
| return tdesc_powerpc_isa205_64l; |
| case PPC_TDESC_ISA205_ALTIVEC: |
| return tdesc_powerpc_isa205_altivec64l; |
| case PPC_TDESC_ISA205_VSX: |
| return tdesc_powerpc_isa205_vsx64l; |
| case PPC_TDESC_ISA205_PPR_DSCR_VSX: |
| return tdesc_powerpc_isa205_ppr_dscr_vsx64l; |
| case PPC_TDESC_ISA207_VSX: |
| return tdesc_powerpc_isa207_vsx64l; |
| case PPC_TDESC_ISA207_HTM_VSX: |
| return tdesc_powerpc_isa207_htm_vsx64l; |
| #else |
| case PPC_TDESC_BASE: |
| return tdesc_powerpc_32l; |
| case PPC_TDESC_ALTIVEC: |
| return tdesc_powerpc_altivec32l; |
| case PPC_TDESC_VSX: |
| return tdesc_powerpc_vsx32l; |
| case PPC_TDESC_ISA205: |
| return tdesc_powerpc_isa205_32l; |
| case PPC_TDESC_ISA205_ALTIVEC: |
| return tdesc_powerpc_isa205_altivec32l; |
| case PPC_TDESC_ISA205_VSX: |
| return tdesc_powerpc_isa205_vsx32l; |
| case PPC_TDESC_ISA205_PPR_DSCR_VSX: |
| return tdesc_powerpc_isa205_ppr_dscr_vsx32l; |
| case PPC_TDESC_ISA207_VSX: |
| return tdesc_powerpc_isa207_vsx32l; |
| case PPC_TDESC_ISA207_HTM_VSX: |
| return tdesc_powerpc_isa207_htm_vsx32l; |
| case PPC_TDESC_E500: |
| return tdesc_powerpc_e500l; |
| #endif |
| default: |
| internal_error (__FILE__, __LINE__, |
| "unknown ipa tdesc index: %d", idx); |
| #ifdef __powerpc64__ |
| return tdesc_powerpc_64l; |
| #else |
| return tdesc_powerpc_32l; |
| #endif |
| } |
| } |
| |
| |
| /* Initialize ipa_tdesc and others. */ |
| |
| void |
| initialize_low_tracepoint (void) |
| { |
| #ifdef __powerpc64__ |
| init_registers_powerpc_64l (); |
| init_registers_powerpc_altivec64l (); |
| init_registers_powerpc_vsx64l (); |
| init_registers_powerpc_isa205_64l (); |
| init_registers_powerpc_isa205_altivec64l (); |
| init_registers_powerpc_isa205_vsx64l (); |
| init_registers_powerpc_isa205_ppr_dscr_vsx64l (); |
| init_registers_powerpc_isa207_vsx64l (); |
| init_registers_powerpc_isa207_htm_vsx64l (); |
| #else |
| init_registers_powerpc_32l (); |
| init_registers_powerpc_altivec32l (); |
| init_registers_powerpc_vsx32l (); |
| init_registers_powerpc_isa205_32l (); |
| init_registers_powerpc_isa205_altivec32l (); |
| init_registers_powerpc_isa205_vsx32l (); |
| init_registers_powerpc_isa205_ppr_dscr_vsx32l (); |
| init_registers_powerpc_isa207_vsx32l (); |
| init_registers_powerpc_isa207_htm_vsx32l (); |
| init_registers_powerpc_e500l (); |
| #endif |
| } |