diff options
Diffstat (limited to 'linux-user/s390x/signal.c')
| -rw-r--r-- | linux-user/s390x/signal.c | 415 |
1 files changed, 415 insertions, 0 deletions
diff --git a/linux-user/s390x/signal.c b/linux-user/s390x/signal.c new file mode 100644 index 000000000..676b94814 --- /dev/null +++ b/linux-user/s390x/signal.c @@ -0,0 +1,415 @@ +/* + * 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" + +#define __NUM_GPRS 16 +#define __NUM_FPRS 16 +#define __NUM_ACRS 16 + +#define __SIGNAL_FRAMESIZE 160 /* FIXME: 31-bit mode -> 96 */ + +#define _SIGCONTEXT_NSIG 64 +#define _SIGCONTEXT_NSIG_BPW 64 /* FIXME: 31-bit mode -> 32 */ +#define _SIGCONTEXT_NSIG_WORDS (_SIGCONTEXT_NSIG / _SIGCONTEXT_NSIG_BPW) +#define _SIGMASK_COPY_SIZE (sizeof(unsigned long)*_SIGCONTEXT_NSIG_WORDS) +#define S390_SYSCALL_OPCODE ((uint16_t)0x0a00) + +typedef struct { + target_psw_t psw; + abi_ulong gprs[__NUM_GPRS]; + abi_uint acrs[__NUM_ACRS]; +} target_s390_regs_common; + +typedef struct { + uint32_t fpc; + uint32_t pad; + uint64_t fprs[__NUM_FPRS]; +} target_s390_fp_regs; + +typedef struct { + target_s390_regs_common regs; + target_s390_fp_regs fpregs; +} target_sigregs; + +typedef struct { + uint64_t vxrs_low[16]; + uint64_t vxrs_high[16][2]; + uint8_t reserved[128]; +} target_sigregs_ext; + +typedef struct { + abi_ulong oldmask[_SIGCONTEXT_NSIG_WORDS]; + abi_ulong sregs; +} target_sigcontext; + +typedef struct { + uint8_t callee_used_stack[__SIGNAL_FRAMESIZE]; + target_sigcontext sc; + target_sigregs sregs; + int signo; + target_sigregs_ext sregs_ext; +} sigframe; + +#define TARGET_UC_VXRS 2 + +struct target_ucontext { + abi_ulong tuc_flags; + abi_ulong tuc_link; + target_stack_t tuc_stack; + target_sigregs tuc_mcontext; + target_sigset_t tuc_sigmask; + uint8_t reserved[128 - sizeof(target_sigset_t)]; + target_sigregs_ext tuc_mcontext_ext; +}; + +typedef struct { + uint8_t callee_used_stack[__SIGNAL_FRAMESIZE]; + struct target_siginfo info; + struct target_ucontext uc; +} rt_sigframe; + +static inline abi_ulong +get_sigframe(struct target_sigaction *ka, CPUS390XState *env, size_t frame_size) +{ + abi_ulong sp; + + /* Default to using normal stack */ + sp = get_sp_from_cpustate(env); + + /* This is the X/Open sanctioned signal stack switching. */ + if (ka->sa_flags & TARGET_SA_ONSTACK) { + sp = target_sigsp(sp, ka); + } + + /* This is the legacy signal stack switching. */ + else if (/* FIXME !user_mode(regs) */ 0 && + !(ka->sa_flags & TARGET_SA_RESTORER) && + ka->sa_restorer) { + sp = (abi_ulong) ka->sa_restorer; + } + + return (sp - frame_size) & -8ul; +} + +#define PSW_USER_BITS (PSW_MASK_DAT | PSW_MASK_IO | PSW_MASK_EXT | \ + PSW_MASK_MCHECK | PSW_MASK_PSTATE | PSW_ASC_PRIMARY) +#define PSW_MASK_USER (PSW_MASK_ASC | PSW_MASK_CC | PSW_MASK_PM | \ + PSW_MASK_64 | PSW_MASK_32) + +static void save_sigregs(CPUS390XState *env, target_sigregs *sregs) +{ + uint64_t psw_mask = s390_cpu_get_psw_mask(env); + int i; + + /* + * Copy a 'clean' PSW mask to the user to avoid leaking + * information about whether PER is currently on. + * TODO: qemu does not support PSW_MASK_RI; it will never be set. + */ + psw_mask = PSW_USER_BITS | (psw_mask & PSW_MASK_USER); + __put_user(psw_mask, &sregs->regs.psw.mask); + __put_user(env->psw.addr, &sregs->regs.psw.addr); + + for (i = 0; i < 16; i++) { + __put_user(env->regs[i], &sregs->regs.gprs[i]); + } + for (i = 0; i < 16; i++) { + __put_user(env->aregs[i], &sregs->regs.acrs[i]); + } + + /* + * We have to store the fp registers to current->thread.fp_regs + * to merge them with the emulated registers. + */ + for (i = 0; i < 16; i++) { + __put_user(*get_freg(env, i), &sregs->fpregs.fprs[i]); + } +} + +static void save_sigregs_ext(CPUS390XState *env, target_sigregs_ext *ext) +{ + int i; + + /* + * if (MACHINE_HAS_VX) ... + * That said, we always allocate the stack storage and the + * space is always available in env. + */ + for (i = 0; i < 16; ++i) { + __put_user(env->vregs[i][1], &ext->vxrs_low[i]); + } + for (i = 0; i < 16; ++i) { + __put_user(env->vregs[i + 16][0], &ext->vxrs_high[i][0]); + __put_user(env->vregs[i + 16][1], &ext->vxrs_high[i][1]); + } +} + +void setup_frame(int sig, struct target_sigaction *ka, + target_sigset_t *set, CPUS390XState *env) +{ + sigframe *frame; + abi_ulong frame_addr; + abi_ulong restorer; + + frame_addr = get_sigframe(ka, env, sizeof(*frame)); + trace_user_setup_frame(env, frame_addr); + if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0)) { + force_sigsegv(sig); + return; + } + + /* Set up backchain. */ + __put_user(env->regs[15], (abi_ulong *) frame); + + /* Create struct sigcontext on the signal stack. */ + /* Make sure that we're initializing all of oldmask. */ + QEMU_BUILD_BUG_ON(ARRAY_SIZE(frame->sc.oldmask) != 1); + __put_user(set->sig[0], &frame->sc.oldmask[0]); + __put_user(frame_addr + offsetof(sigframe, sregs), &frame->sc.sregs); + + /* Create _sigregs on the signal stack */ + save_sigregs(env, &frame->sregs); + + /* + * ??? The kernel uses regs->gprs[2] here, which is not yet the signo. + * Moreover the comment talks about allowing backtrace, which is really + * done by the r15 copy above. + */ + __put_user(sig, &frame->signo); + + /* Create sigregs_ext on the signal stack. */ + save_sigregs_ext(env, &frame->sregs_ext); + + /* + * Set up to return from userspace. + * If provided, use a stub already in userspace. + */ + if (ka->sa_flags & TARGET_SA_RESTORER) { + restorer = ka->sa_restorer; + } else { + restorer = default_sigreturn; + } + + /* Set up registers for signal handler */ + env->regs[14] = restorer; + env->regs[15] = frame_addr; + /* Force default amode and default user address space control. */ + env->psw.mask = PSW_MASK_64 | PSW_MASK_32 | PSW_ASC_PRIMARY + | (env->psw.mask & ~PSW_MASK_ASC); + env->psw.addr = ka->_sa_handler; + + env->regs[2] = sig; + env->regs[3] = frame_addr + offsetof(typeof(*frame), sc); + + /* + * We forgot to include these in the sigcontext. + * To avoid breaking binary compatibility, they are passed as args. + */ + env->regs[4] = 0; /* FIXME: regs->int_code & 127 */ + env->regs[5] = 0; /* FIXME: regs->int_parm_long */ + env->regs[6] = 0; /* FIXME: current->thread.last_break */ + + unlock_user_struct(frame, frame_addr, 1); +} + +void setup_rt_frame(int sig, struct target_sigaction *ka, + target_siginfo_t *info, + target_sigset_t *set, CPUS390XState *env) +{ + rt_sigframe *frame; + abi_ulong frame_addr; + abi_ulong restorer; + abi_ulong uc_flags; + + frame_addr = get_sigframe(ka, env, sizeof *frame); + trace_user_setup_rt_frame(env, frame_addr); + if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0)) { + force_sigsegv(sig); + return; + } + + /* Set up backchain. */ + __put_user(env->regs[15], (abi_ulong *) frame); + + /* + * Set up to return from userspace. + * If provided, use a stub already in userspace. + */ + if (ka->sa_flags & TARGET_SA_RESTORER) { + restorer = ka->sa_restorer; + } else { + restorer = default_rt_sigreturn; + } + + /* Create siginfo on the signal stack. */ + tswap_siginfo(&frame->info, info); + + /* Create ucontext on the signal stack. */ + uc_flags = 0; + if (s390_has_feat(S390_FEAT_VECTOR)) { + uc_flags |= TARGET_UC_VXRS; + } + __put_user(uc_flags, &frame->uc.tuc_flags); + __put_user(0, &frame->uc.tuc_link); + target_save_altstack(&frame->uc.tuc_stack, env); + save_sigregs(env, &frame->uc.tuc_mcontext); + save_sigregs_ext(env, &frame->uc.tuc_mcontext_ext); + tswap_sigset(&frame->uc.tuc_sigmask, set); + + /* Set up registers for signal handler */ + env->regs[14] = restorer; + env->regs[15] = frame_addr; + /* Force default amode and default user address space control. */ + env->psw.mask = PSW_MASK_64 | PSW_MASK_32 | PSW_ASC_PRIMARY + | (env->psw.mask & ~PSW_MASK_ASC); + env->psw.addr = ka->_sa_handler; + + env->regs[2] = sig; + env->regs[3] = frame_addr + offsetof(typeof(*frame), info); + env->regs[4] = frame_addr + offsetof(typeof(*frame), uc); + env->regs[5] = 0; /* FIXME: current->thread.last_break */ +} + +static void restore_sigregs(CPUS390XState *env, target_sigregs *sc) +{ + uint64_t prev_addr, prev_mask, mask, addr; + int i; + + for (i = 0; i < 16; i++) { + __get_user(env->regs[i], &sc->regs.gprs[i]); + } + + prev_addr = env->psw.addr; + __get_user(mask, &sc->regs.psw.mask); + __get_user(addr, &sc->regs.psw.addr); + trace_user_s390x_restore_sigregs(env, addr, prev_addr); + + /* + * Use current psw.mask to preserve PER bit. + * TODO: + * if (!is_ri_task(current) && (user_sregs.regs.psw.mask & PSW_MASK_RI)) + * return -EINVAL; + * Simply do not allow it to be set in mask. + */ + prev_mask = s390_cpu_get_psw_mask(env); + mask = (prev_mask & ~PSW_MASK_USER) | (mask & PSW_MASK_USER); + /* Check for invalid user address space control. */ + if ((mask & PSW_MASK_ASC) == PSW_ASC_HOME) { + mask = (mask & ~PSW_MASK_ASC) | PSW_ASC_PRIMARY; + } + /* Check for invalid amode. */ + if (mask & PSW_MASK_64) { + mask |= PSW_MASK_32; + } + s390_cpu_set_psw(env, mask, addr); + + for (i = 0; i < 16; i++) { + __get_user(env->aregs[i], &sc->regs.acrs[i]); + } + for (i = 0; i < 16; i++) { + __get_user(*get_freg(env, i), &sc->fpregs.fprs[i]); + } +} + +static void restore_sigregs_ext(CPUS390XState *env, target_sigregs_ext *ext) +{ + int i; + + /* + * if (MACHINE_HAS_VX) ... + * That said, we always allocate the stack storage and the + * space is always available in env. + */ + for (i = 0; i < 16; ++i) { + __get_user(env->vregs[i][1], &ext->vxrs_low[i]); + } + for (i = 0; i < 16; ++i) { + __get_user(env->vregs[i + 16][0], &ext->vxrs_high[i][0]); + __get_user(env->vregs[i + 16][1], &ext->vxrs_high[i][1]); + } +} + +long do_sigreturn(CPUS390XState *env) +{ + sigframe *frame; + abi_ulong frame_addr = env->regs[15]; + target_sigset_t target_set; + sigset_t set; + + trace_user_do_sigreturn(env, frame_addr); + if (!lock_user_struct(VERIFY_READ, frame, frame_addr, 1)) { + force_sig(TARGET_SIGSEGV); + return -TARGET_QEMU_ESIGRETURN; + } + + /* Make sure that we're initializing all of target_set. */ + QEMU_BUILD_BUG_ON(ARRAY_SIZE(target_set.sig) != 1); + __get_user(target_set.sig[0], &frame->sc.oldmask[0]); + + target_to_host_sigset_internal(&set, &target_set); + set_sigmask(&set); /* ~_BLOCKABLE? */ + + restore_sigregs(env, &frame->sregs); + restore_sigregs_ext(env, &frame->sregs_ext); + + unlock_user_struct(frame, frame_addr, 0); + return -TARGET_QEMU_ESIGRETURN; +} + +long do_rt_sigreturn(CPUS390XState *env) +{ + rt_sigframe *frame; + abi_ulong frame_addr = env->regs[15]; + sigset_t set; + + trace_user_do_rt_sigreturn(env, frame_addr); + if (!lock_user_struct(VERIFY_READ, frame, frame_addr, 1)) { + force_sig(TARGET_SIGSEGV); + return -TARGET_QEMU_ESIGRETURN; + } + target_to_host_sigset(&set, &frame->uc.tuc_sigmask); + + set_sigmask(&set); /* ~_BLOCKABLE? */ + + restore_sigregs(env, &frame->uc.tuc_mcontext); + restore_sigregs_ext(env, &frame->uc.tuc_mcontext_ext); + + target_restore_altstack(&frame->uc.tuc_stack, env); + + unlock_user_struct(frame, frame_addr, 0); + return -TARGET_QEMU_ESIGRETURN; +} + +void setup_sigtramp(abi_ulong sigtramp_page) +{ + uint16_t *tramp = lock_user(VERIFY_WRITE, sigtramp_page, 2 + 2, 0); + assert(tramp != NULL); + + default_sigreturn = sigtramp_page; + __put_user(S390_SYSCALL_OPCODE | TARGET_NR_sigreturn, &tramp[0]); + + default_rt_sigreturn = sigtramp_page + 2; + __put_user(S390_SYSCALL_OPCODE | TARGET_NR_rt_sigreturn, &tramp[1]); + + unlock_user(tramp, sigtramp_page, 2 + 2); +} |