| /* |
| * i386 breakpoint helpers |
| * |
| * Copyright (c) 2003 Fabrice Bellard |
| * |
| * This library is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Lesser General Public |
| * License as published by the Free Software Foundation; either |
| * version 2 of the License, or (at your option) any later version. |
| * |
| * This library 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 |
| * Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public |
| * License along with this library; if not, see <http://www.gnu.org/licenses/>. |
| */ |
| |
| #include "qemu/osdep.h" |
| #include "cpu.h" |
| #include "exec/exec-all.h" |
| #include "exec/helper-proto.h" |
| |
| |
| #ifndef CONFIG_USER_ONLY |
| static inline bool hw_local_breakpoint_enabled(unsigned long dr7, int index) |
| { |
| return (dr7 >> (index * 2)) & 1; |
| } |
| |
| static inline bool hw_global_breakpoint_enabled(unsigned long dr7, int index) |
| { |
| return (dr7 >> (index * 2)) & 2; |
| |
| } |
| static inline bool hw_breakpoint_enabled(unsigned long dr7, int index) |
| { |
| return hw_global_breakpoint_enabled(dr7, index) || |
| hw_local_breakpoint_enabled(dr7, index); |
| } |
| |
| static inline int hw_breakpoint_type(unsigned long dr7, int index) |
| { |
| return (dr7 >> (DR7_TYPE_SHIFT + (index * 4))) & 3; |
| } |
| |
| static inline int hw_breakpoint_len(unsigned long dr7, int index) |
| { |
| int len = ((dr7 >> (DR7_LEN_SHIFT + (index * 4))) & 3); |
| return (len == 2) ? 8 : len + 1; |
| } |
| |
| static int hw_breakpoint_insert(CPUX86State *env, int index) |
| { |
| CPUState *cs = CPU(x86_env_get_cpu(env)); |
| target_ulong dr7 = env->dr[7]; |
| target_ulong drN = env->dr[index]; |
| int err = 0; |
| |
| switch (hw_breakpoint_type(dr7, index)) { |
| case DR7_TYPE_BP_INST: |
| if (hw_breakpoint_enabled(dr7, index)) { |
| err = cpu_breakpoint_insert(cs, drN, BP_CPU, |
| &env->cpu_breakpoint[index]); |
| } |
| break; |
| |
| case DR7_TYPE_IO_RW: |
| /* Notice when we should enable calls to bpt_io. */ |
| return hw_breakpoint_enabled(env->dr[7], index) |
| ? HF_IOBPT_MASK : 0; |
| |
| case DR7_TYPE_DATA_WR: |
| if (hw_breakpoint_enabled(dr7, index)) { |
| err = cpu_watchpoint_insert(cs, drN, |
| hw_breakpoint_len(dr7, index), |
| BP_CPU | BP_MEM_WRITE, |
| &env->cpu_watchpoint[index]); |
| } |
| break; |
| |
| case DR7_TYPE_DATA_RW: |
| if (hw_breakpoint_enabled(dr7, index)) { |
| err = cpu_watchpoint_insert(cs, drN, |
| hw_breakpoint_len(dr7, index), |
| BP_CPU | BP_MEM_ACCESS, |
| &env->cpu_watchpoint[index]); |
| } |
| break; |
| } |
| if (err) { |
| env->cpu_breakpoint[index] = NULL; |
| } |
| return 0; |
| } |
| |
| static void hw_breakpoint_remove(CPUX86State *env, int index) |
| { |
| CPUState *cs = CPU(x86_env_get_cpu(env)); |
| |
| switch (hw_breakpoint_type(env->dr[7], index)) { |
| case DR7_TYPE_BP_INST: |
| if (env->cpu_breakpoint[index]) { |
| cpu_breakpoint_remove_by_ref(cs, env->cpu_breakpoint[index]); |
| env->cpu_breakpoint[index] = NULL; |
| } |
| break; |
| |
| case DR7_TYPE_DATA_WR: |
| case DR7_TYPE_DATA_RW: |
| if (env->cpu_breakpoint[index]) { |
| cpu_watchpoint_remove_by_ref(cs, env->cpu_watchpoint[index]); |
| env->cpu_breakpoint[index] = NULL; |
| } |
| break; |
| |
| case DR7_TYPE_IO_RW: |
| /* HF_IOBPT_MASK cleared elsewhere. */ |
| break; |
| } |
| } |
| |
| void cpu_x86_update_dr7(CPUX86State *env, uint32_t new_dr7) |
| { |
| target_ulong old_dr7 = env->dr[7]; |
| int iobpt = 0; |
| int i; |
| |
| new_dr7 |= DR7_FIXED_1; |
| |
| /* If nothing is changing except the global/local enable bits, |
| then we can make the change more efficient. */ |
| if (((old_dr7 ^ new_dr7) & ~0xff) == 0) { |
| /* Fold the global and local enable bits together into the |
| global fields, then xor to show which registers have |
| changed collective enable state. */ |
| int mod = ((old_dr7 | old_dr7 * 2) ^ (new_dr7 | new_dr7 * 2)) & 0xff; |
| |
| for (i = 0; i < DR7_MAX_BP; i++) { |
| if ((mod & (2 << i * 2)) && !hw_breakpoint_enabled(new_dr7, i)) { |
| hw_breakpoint_remove(env, i); |
| } |
| } |
| env->dr[7] = new_dr7; |
| for (i = 0; i < DR7_MAX_BP; i++) { |
| if (mod & (2 << i * 2) && hw_breakpoint_enabled(new_dr7, i)) { |
| iobpt |= hw_breakpoint_insert(env, i); |
| } else if (hw_breakpoint_type(new_dr7, i) == DR7_TYPE_IO_RW |
| && hw_breakpoint_enabled(new_dr7, i)) { |
| iobpt |= HF_IOBPT_MASK; |
| } |
| } |
| } else { |
| for (i = 0; i < DR7_MAX_BP; i++) { |
| hw_breakpoint_remove(env, i); |
| } |
| env->dr[7] = new_dr7; |
| for (i = 0; i < DR7_MAX_BP; i++) { |
| iobpt |= hw_breakpoint_insert(env, i); |
| } |
| } |
| |
| env->hflags = (env->hflags & ~HF_IOBPT_MASK) | iobpt; |
| } |
| |
| static bool check_hw_breakpoints(CPUX86State *env, bool force_dr6_update) |
| { |
| target_ulong dr6; |
| int reg; |
| bool hit_enabled = false; |
| |
| dr6 = env->dr[6] & ~0xf; |
| for (reg = 0; reg < DR7_MAX_BP; reg++) { |
| bool bp_match = false; |
| bool wp_match = false; |
| |
| switch (hw_breakpoint_type(env->dr[7], reg)) { |
| case DR7_TYPE_BP_INST: |
| if (env->dr[reg] == env->eip) { |
| bp_match = true; |
| } |
| break; |
| case DR7_TYPE_DATA_WR: |
| case DR7_TYPE_DATA_RW: |
| if (env->cpu_watchpoint[reg] && |
| env->cpu_watchpoint[reg]->flags & BP_WATCHPOINT_HIT) { |
| wp_match = true; |
| } |
| break; |
| case DR7_TYPE_IO_RW: |
| break; |
| } |
| if (bp_match || wp_match) { |
| dr6 |= 1 << reg; |
| if (hw_breakpoint_enabled(env->dr[7], reg)) { |
| hit_enabled = true; |
| } |
| } |
| } |
| |
| if (hit_enabled || force_dr6_update) { |
| env->dr[6] = dr6; |
| } |
| |
| return hit_enabled; |
| } |
| |
| void breakpoint_handler(CPUState *cs) |
| { |
| X86CPU *cpu = X86_CPU(cs); |
| CPUX86State *env = &cpu->env; |
| CPUBreakpoint *bp; |
| |
| if (cs->watchpoint_hit) { |
| if (cs->watchpoint_hit->flags & BP_CPU) { |
| cs->watchpoint_hit = NULL; |
| if (check_hw_breakpoints(env, false)) { |
| raise_exception(env, EXCP01_DB); |
| } else { |
| cpu_loop_exit_noexc(cs); |
| } |
| } |
| } else { |
| QTAILQ_FOREACH(bp, &cs->breakpoints, entry) { |
| if (bp->pc == env->eip) { |
| if (bp->flags & BP_CPU) { |
| check_hw_breakpoints(env, true); |
| raise_exception(env, EXCP01_DB); |
| } |
| break; |
| } |
| } |
| } |
| } |
| #endif |
| |
| void helper_single_step(CPUX86State *env) |
| { |
| #ifndef CONFIG_USER_ONLY |
| check_hw_breakpoints(env, true); |
| env->dr[6] |= DR6_BS; |
| #endif |
| raise_exception(env, EXCP01_DB); |
| } |
| |
| void helper_rechecking_single_step(CPUX86State *env) |
| { |
| if ((env->eflags & TF_MASK) != 0) { |
| helper_single_step(env); |
| } |
| } |
| |
| void helper_set_dr(CPUX86State *env, int reg, target_ulong t0) |
| { |
| #ifndef CONFIG_USER_ONLY |
| switch (reg) { |
| case 0: case 1: case 2: case 3: |
| if (hw_breakpoint_enabled(env->dr[7], reg) |
| && hw_breakpoint_type(env->dr[7], reg) != DR7_TYPE_IO_RW) { |
| hw_breakpoint_remove(env, reg); |
| env->dr[reg] = t0; |
| hw_breakpoint_insert(env, reg); |
| } else { |
| env->dr[reg] = t0; |
| } |
| return; |
| case 4: |
| if (env->cr[4] & CR4_DE_MASK) { |
| break; |
| } |
| /* fallthru */ |
| case 6: |
| env->dr[6] = t0 | DR6_FIXED_1; |
| return; |
| case 5: |
| if (env->cr[4] & CR4_DE_MASK) { |
| break; |
| } |
| /* fallthru */ |
| case 7: |
| cpu_x86_update_dr7(env, t0); |
| return; |
| } |
| raise_exception_err_ra(env, EXCP06_ILLOP, 0, GETPC()); |
| #endif |
| } |
| |
| target_ulong helper_get_dr(CPUX86State *env, int reg) |
| { |
| switch (reg) { |
| case 0: case 1: case 2: case 3: case 6: case 7: |
| return env->dr[reg]; |
| case 4: |
| if (env->cr[4] & CR4_DE_MASK) { |
| break; |
| } else { |
| return env->dr[6]; |
| } |
| case 5: |
| if (env->cr[4] & CR4_DE_MASK) { |
| break; |
| } else { |
| return env->dr[7]; |
| } |
| } |
| raise_exception_err_ra(env, EXCP06_ILLOP, 0, GETPC()); |
| } |
| |
| /* Check if Port I/O is trapped by a breakpoint. */ |
| void helper_bpt_io(CPUX86State *env, uint32_t port, |
| uint32_t size, target_ulong next_eip) |
| { |
| #ifndef CONFIG_USER_ONLY |
| target_ulong dr7 = env->dr[7]; |
| int i, hit = 0; |
| |
| for (i = 0; i < DR7_MAX_BP; ++i) { |
| if (hw_breakpoint_type(dr7, i) == DR7_TYPE_IO_RW |
| && hw_breakpoint_enabled(dr7, i)) { |
| int bpt_len = hw_breakpoint_len(dr7, i); |
| if (port + size - 1 >= env->dr[i] |
| && port <= env->dr[i] + bpt_len - 1) { |
| hit |= 1 << i; |
| } |
| } |
| } |
| |
| if (hit) { |
| env->dr[6] = (env->dr[6] & ~0xf) | hit; |
| env->eip = next_eip; |
| raise_exception(env, EXCP01_DB); |
| } |
| #endif |
| } |
