| /* |
| * Emulation of Linux signals |
| * |
| * Copyright (c) 2003 Fabrice Bellard |
| * |
| * 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 2 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 "qemu/osdep.h" |
| #include "qemu.h" |
| #include "user-internals.h" |
| #include "signal-common.h" |
| #include "linux-user/trace.h" |
| |
| struct target_sigcontext { |
| abi_ulong sc_pc; |
| abi_ulong sc_ps; |
| abi_ulong sc_lbeg; |
| abi_ulong sc_lend; |
| abi_ulong sc_lcount; |
| abi_ulong sc_sar; |
| abi_ulong sc_acclo; |
| abi_ulong sc_acchi; |
| abi_ulong sc_a[16]; |
| abi_ulong sc_xtregs; |
| }; |
| |
| struct target_ucontext { |
| abi_ulong tuc_flags; |
| abi_ulong tuc_link; |
| target_stack_t tuc_stack; |
| struct target_sigcontext tuc_mcontext; |
| target_sigset_t tuc_sigmask; |
| }; |
| |
| struct target_rt_sigframe { |
| target_siginfo_t info; |
| struct target_ucontext uc; |
| /* TODO: xtregs */ |
| uint8_t retcode[6]; |
| abi_ulong window[4]; |
| }; |
| |
| static abi_ulong get_sigframe(struct target_sigaction *sa, |
| CPUXtensaState *env, |
| unsigned long framesize) |
| { |
| abi_ulong sp; |
| |
| sp = target_sigsp(get_sp_from_cpustate(env), sa); |
| |
| return (sp - framesize) & -16; |
| } |
| |
| static int flush_window_regs(CPUXtensaState *env) |
| { |
| uint32_t wb = env->sregs[WINDOW_BASE]; |
| uint32_t ws = xtensa_replicate_windowstart(env) >> (wb + 1); |
| unsigned d = ctz32(ws) + 1; |
| unsigned i; |
| int ret = 0; |
| |
| for (i = d; i < env->config->nareg / 4; i += d) { |
| uint32_t ssp, osp; |
| unsigned j; |
| |
| ws >>= d; |
| xtensa_rotate_window(env, d); |
| |
| if (ws & 0x1) { |
| ssp = env->regs[5]; |
| d = 1; |
| } else if (ws & 0x2) { |
| ssp = env->regs[9]; |
| ret |= get_user_ual(osp, env->regs[1] - 12); |
| osp -= 32; |
| d = 2; |
| } else if (ws & 0x4) { |
| ssp = env->regs[13]; |
| ret |= get_user_ual(osp, env->regs[1] - 12); |
| osp -= 48; |
| d = 3; |
| } else { |
| g_assert_not_reached(); |
| } |
| |
| for (j = 0; j < 4; ++j) { |
| ret |= put_user_ual(env->regs[j], ssp - 16 + j * 4); |
| } |
| for (j = 4; j < d * 4; ++j) { |
| ret |= put_user_ual(env->regs[j], osp - 16 + j * 4); |
| } |
| } |
| xtensa_rotate_window(env, d); |
| g_assert(env->sregs[WINDOW_BASE] == wb); |
| return ret == 0; |
| } |
| |
| static int setup_sigcontext(struct target_rt_sigframe *frame, |
| CPUXtensaState *env) |
| { |
| struct target_sigcontext *sc = &frame->uc.tuc_mcontext; |
| int i; |
| |
| __put_user(env->pc, &sc->sc_pc); |
| __put_user(env->sregs[PS], &sc->sc_ps); |
| __put_user(env->sregs[LBEG], &sc->sc_lbeg); |
| __put_user(env->sregs[LEND], &sc->sc_lend); |
| __put_user(env->sregs[LCOUNT], &sc->sc_lcount); |
| if (!flush_window_regs(env)) { |
| return 0; |
| } |
| for (i = 0; i < 16; ++i) { |
| __put_user(env->regs[i], sc->sc_a + i); |
| } |
| __put_user(0, &sc->sc_xtregs); |
| /* TODO: xtregs */ |
| return 1; |
| } |
| |
| static void install_sigtramp(uint8_t *tramp) |
| { |
| #if TARGET_BIG_ENDIAN |
| /* Generate instruction: MOVI a2, __NR_rt_sigreturn */ |
| __put_user(0x22, &tramp[0]); |
| __put_user(0x0a, &tramp[1]); |
| __put_user(TARGET_NR_rt_sigreturn, &tramp[2]); |
| /* Generate instruction: SYSCALL */ |
| __put_user(0x00, &tramp[3]); |
| __put_user(0x05, &tramp[4]); |
| __put_user(0x00, &tramp[5]); |
| #else |
| /* Generate instruction: MOVI a2, __NR_rt_sigreturn */ |
| __put_user(0x22, &tramp[0]); |
| __put_user(0xa0, &tramp[1]); |
| __put_user(TARGET_NR_rt_sigreturn, &tramp[2]); |
| /* Generate instruction: SYSCALL */ |
| __put_user(0x00, &tramp[3]); |
| __put_user(0x50, &tramp[4]); |
| __put_user(0x00, &tramp[5]); |
| #endif |
| } |
| |
| void setup_rt_frame(int sig, struct target_sigaction *ka, |
| target_siginfo_t *info, |
| target_sigset_t *set, CPUXtensaState *env) |
| { |
| abi_ulong frame_addr; |
| struct target_rt_sigframe *frame; |
| int is_fdpic = info_is_fdpic(get_task_state(thread_cpu)->info); |
| abi_ulong handler = 0; |
| abi_ulong handler_fdpic_GOT = 0; |
| uint32_t ra; |
| bool abi_call0; |
| unsigned base; |
| int i; |
| |
| frame_addr = get_sigframe(ka, env, sizeof(*frame)); |
| trace_user_setup_rt_frame(env, frame_addr); |
| |
| if (is_fdpic) { |
| abi_ulong funcdesc_ptr = ka->_sa_handler; |
| |
| if (get_user_ual(handler, funcdesc_ptr) |
| || get_user_ual(handler_fdpic_GOT, funcdesc_ptr + 4)) { |
| goto give_sigsegv; |
| } |
| } else { |
| handler = ka->_sa_handler; |
| } |
| |
| if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0)) { |
| goto give_sigsegv; |
| } |
| |
| if (ka->sa_flags & SA_SIGINFO) { |
| frame->info = *info; |
| } |
| |
| __put_user(0, &frame->uc.tuc_flags); |
| __put_user(0, &frame->uc.tuc_link); |
| target_save_altstack(&frame->uc.tuc_stack, env); |
| if (!setup_sigcontext(frame, env)) { |
| unlock_user_struct(frame, frame_addr, 0); |
| goto give_sigsegv; |
| } |
| for (i = 0; i < TARGET_NSIG_WORDS; ++i) { |
| __put_user(set->sig[i], &frame->uc.tuc_sigmask.sig[i]); |
| } |
| |
| if (ka->sa_flags & TARGET_SA_RESTORER) { |
| if (is_fdpic) { |
| if (get_user_ual(ra, ka->sa_restorer)) { |
| unlock_user_struct(frame, frame_addr, 0); |
| goto give_sigsegv; |
| } |
| } else { |
| ra = ka->sa_restorer; |
| } |
| } else { |
| /* Not used, but retain for ABI compatibility. */ |
| install_sigtramp(frame->retcode); |
| ra = default_rt_sigreturn; |
| } |
| memset(env->regs, 0, sizeof(env->regs)); |
| env->pc = handler; |
| env->regs[1] = frame_addr; |
| env->sregs[WINDOW_BASE] = 0; |
| env->sregs[WINDOW_START] = 1; |
| |
| abi_call0 = (env->sregs[PS] & PS_WOE) == 0; |
| env->sregs[PS] = PS_UM | (3 << PS_RING_SHIFT); |
| |
| if (abi_call0) { |
| base = 0; |
| env->regs[base] = ra; |
| } else { |
| env->sregs[PS] |= PS_WOE | (1 << PS_CALLINC_SHIFT); |
| base = 4; |
| env->regs[base] = (ra & 0x3fffffff) | 0x40000000; |
| } |
| env->regs[base + 2] = sig; |
| env->regs[base + 3] = frame_addr + offsetof(struct target_rt_sigframe, |
| info); |
| env->regs[base + 4] = frame_addr + offsetof(struct target_rt_sigframe, uc); |
| if (is_fdpic) { |
| env->regs[base + 11] = handler_fdpic_GOT; |
| } |
| unlock_user_struct(frame, frame_addr, 1); |
| return; |
| |
| give_sigsegv: |
| force_sigsegv(sig); |
| return; |
| } |
| |
| static void restore_sigcontext(CPUXtensaState *env, |
| struct target_rt_sigframe *frame) |
| { |
| struct target_sigcontext *sc = &frame->uc.tuc_mcontext; |
| uint32_t ps; |
| int i; |
| |
| __get_user(env->pc, &sc->sc_pc); |
| __get_user(ps, &sc->sc_ps); |
| __get_user(env->sregs[LBEG], &sc->sc_lbeg); |
| __get_user(env->sregs[LEND], &sc->sc_lend); |
| __get_user(env->sregs[LCOUNT], &sc->sc_lcount); |
| |
| env->sregs[WINDOW_BASE] = 0; |
| env->sregs[WINDOW_START] = 1; |
| env->sregs[PS] = deposit32(env->sregs[PS], |
| PS_CALLINC_SHIFT, |
| PS_CALLINC_LEN, |
| extract32(ps, PS_CALLINC_SHIFT, |
| PS_CALLINC_LEN)); |
| for (i = 0; i < 16; ++i) { |
| __get_user(env->regs[i], sc->sc_a + i); |
| } |
| /* TODO: xtregs */ |
| } |
| |
| long do_rt_sigreturn(CPUXtensaState *env) |
| { |
| abi_ulong frame_addr = env->regs[1]; |
| struct target_rt_sigframe *frame; |
| sigset_t set; |
| |
| trace_user_do_rt_sigreturn(env, frame_addr); |
| if (!lock_user_struct(VERIFY_READ, frame, frame_addr, 1)) { |
| goto badframe; |
| } |
| target_to_host_sigset(&set, &frame->uc.tuc_sigmask); |
| set_sigmask(&set); |
| |
| restore_sigcontext(env, frame); |
| target_restore_altstack(&frame->uc.tuc_stack, env); |
| |
| unlock_user_struct(frame, frame_addr, 0); |
| return -QEMU_ESIGRETURN; |
| |
| badframe: |
| unlock_user_struct(frame, frame_addr, 0); |
| force_sig(TARGET_SIGSEGV); |
| return -QEMU_ESIGRETURN; |
| } |
| |
| void setup_sigtramp(abi_ulong sigtramp_page) |
| { |
| uint8_t *tramp = lock_user(VERIFY_WRITE, sigtramp_page, 6, 0); |
| assert(tramp != NULL); |
| |
| default_rt_sigreturn = sigtramp_page; |
| install_sigtramp(tramp); |
| unlock_user(tramp, sigtramp_page, 6); |
| } |
