/*
* 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 "signal-common.h"
#include "linux-user/trace.h"
#define MCONTEXT_VERSION 2
struct target_sigcontext {
int version;
unsigned long gregs[32];
};
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; /* mask last for extensibility */
};
struct target_rt_sigframe {
struct target_siginfo info;
struct target_ucontext uc;
};
static int rt_setup_ucontext(struct target_ucontext *uc, CPUNios2State *env)
{
unsigned long *gregs = uc->tuc_mcontext.gregs;
__put_user(MCONTEXT_VERSION, &uc->tuc_mcontext.version);
__put_user(env->regs[1], &gregs[0]);
__put_user(env->regs[2], &gregs[1]);
__put_user(env->regs[3], &gregs[2]);
__put_user(env->regs[4], &gregs[3]);
__put_user(env->regs[5], &gregs[4]);
__put_user(env->regs[6], &gregs[5]);
__put_user(env->regs[7], &gregs[6]);
__put_user(env->regs[8], &gregs[7]);
__put_user(env->regs[9], &gregs[8]);
__put_user(env->regs[10], &gregs[9]);
__put_user(env->regs[11], &gregs[10]);
__put_user(env->regs[12], &gregs[11]);
__put_user(env->regs[13], &gregs[12]);
__put_user(env->regs[14], &gregs[13]);
__put_user(env->regs[15], &gregs[14]);
__put_user(env->regs[16], &gregs[15]);
__put_user(env->regs[17], &gregs[16]);
__put_user(env->regs[18], &gregs[17]);
__put_user(env->regs[19], &gregs[18]);
__put_user(env->regs[20], &gregs[19]);
__put_user(env->regs[21], &gregs[20]);
__put_user(env->regs[22], &gregs[21]);
__put_user(env->regs[23], &gregs[22]);
__put_user(env->regs[R_RA], &gregs[23]);
__put_user(env->regs[R_FP], &gregs[24]);
__put_user(env->regs[R_GP], &gregs[25]);
__put_user(env->regs[R_EA], &gregs[27]);
__put_user(env->regs[R_SP], &gregs[28]);
return 0;
}
static int rt_restore_ucontext(CPUNios2State *env, struct target_ucontext *uc,
int *pr2)
{
int temp;
abi_ulong off, frame_addr = env->regs[R_SP];
unsigned long *gregs = uc->tuc_mcontext.gregs;
int err;
/* Always make any pending restarted system calls return -EINTR */
/* current->restart_block.fn = do_no_restart_syscall; */
__get_user(temp, &uc->tuc_mcontext.version);
if (temp != MCONTEXT_VERSION) {
return 1;
}
/* restore passed registers */
__get_user(env->regs[1], &gregs[0]);
__get_user(env->regs[2], &gregs[1]);
__get_user(env->regs[3], &gregs[2]);
__get_user(env->regs[4], &gregs[3]);
__get_user(env->regs[5], &gregs[4]);
__get_user(env->regs[6], &gregs[5]);
__get_user(env->regs[7], &gregs[6]);
__get_user(env->regs[8], &gregs[7]);
__get_user(env->regs[9], &gregs[8]);
__get_user(env->regs[10], &gregs[9]);
__get_user(env->regs[11], &gregs[10]);
__get_user(env->regs[12], &gregs[11]);
__get_user(env->regs[13], &gregs[12]);
__get_user(env->regs[14], &gregs[13]);
__get_user(env->regs[15], &gregs[14]);
__get_user(env->regs[16], &gregs[15]);
__get_user(env->regs[17], &gregs[16]);
__get_user(env->regs[18], &gregs[17]);
__get_user(env->regs[19], &gregs[18]);
__get_user(env->regs[20], &gregs[19]);
__get_user(env->regs[21], &gregs[20]);
__get_user(env->regs[22], &gregs[21]);
__get_user(env->regs[23], &gregs[22]);
/* gregs[23] is handled below */
/* Verify, should this be settable */
__get_user(env->regs[R_FP], &gregs[24]);
/* Verify, should this be settable */
__get_user(env->regs[R_GP], &gregs[25]);
/* Not really necessary no user settable bits */
__get_user(temp, &gregs[26]);
__get_user(env->regs[R_EA], &gregs[27]);
__get_user(env->regs[R_RA], &gregs[23]);
__get_user(env->regs[R_SP], &gregs[28]);
off = offsetof(struct target_rt_sigframe, uc.tuc_stack);
err = do_sigaltstack(frame_addr + off, 0, get_sp_from_cpustate(env));
if (err == -EFAULT) {
return 1;
}
*pr2 = env->regs[2];
return 0;
}
static void *get_sigframe(struct target_sigaction *ka, CPUNios2State *env,
size_t frame_size)
{
unsigned long usp;
/* This is the X/Open sanctioned signal stack switching. */
usp = target_sigsp(get_sp_from_cpustate(env), ka);
/* Verify, is it 32 or 64 bit aligned */
return (void *)((usp - frame_size) & -8UL);
}
void setup_rt_frame(int sig, struct target_sigaction *ka,
target_siginfo_t *info,
target_sigset_t *set,
CPUNios2State *env)
{
struct target_rt_sigframe *frame;
int i, err = 0;
frame = get_sigframe(ka, env, sizeof(*frame));
if (ka->sa_flags & SA_SIGINFO) {
tswap_siginfo(&frame->info, info);
}
/* Create the ucontext. */
__put_user(0, &frame->uc.tuc_flags);
__put_user(0, &frame->uc.tuc_link);
target_save_altstack(&frame->uc.tuc_stack, env);
err |= rt_setup_ucontext(&frame->uc, env);
for (i = 0; i < TARGET_NSIG_WORDS; i++) {
__put_user((abi_ulong)set->sig[i],
(abi_ulong *)&frame->uc.tuc_sigmask.sig[i]);
}
if (err) {
goto give_sigsegv;
}
/* Set up to return from userspace; jump to fixed address sigreturn
trampoline on kuser page. */
env->regs[R_RA] = (unsigned long) (0x1044);
/* Set up registers for signal handler */
env->regs[R_SP] = (unsigned long) frame;
env->regs[4] = (unsigned long) sig;
env->regs[5] = (unsigned long) &frame->info;
env->regs[6] = (unsigned long) &frame->uc;
env->regs[R_EA] = (unsigned long) ka->_sa_handler;
return;
give_sigsegv:
if (sig == TARGET_SIGSEGV) {
ka->_sa_handler = TARGET_SIG_DFL;
}
force_sigsegv(sig);
return;
}
long do_sigreturn(CPUNios2State *env)
{
trace_user_do_sigreturn(env, 0);
qemu_log_mask(LOG_UNIMP, "do_sigreturn: not implemented\n");
return -TARGET_ENOSYS;
}
long do_rt_sigreturn(CPUNios2State *env)
{
/* Verify, can we follow the stack back */
abi_ulong frame_addr = env->regs[R_SP];
struct target_rt_sigframe *frame;
sigset_t set;
int rval;
if (!lock_user_struct(VERIFY_READ, frame, frame_addr, 1)) {
goto badframe;
}
target_to_host_sigset(&set, &frame->uc.tuc_sigmask);
do_sigprocmask(SIG_SETMASK, &set, NULL);
if (rt_restore_ucontext(env, &frame->uc, &rval)) {
goto badframe;
}
unlock_user_struct(frame, frame_addr, 0);
return rval;
badframe:
unlock_user_struct(frame, frame_addr, 0);
force_sig(TARGET_SIGSEGV);
return 0;
}
