linux-user: Support for restarting system calls for CRIS targets

Update the CRIS main loop and sigreturn code:
 * on TARGET_ERESTARTSYS, wind guest PC backwards to repeat syscall insn
 * set all guest CPU state within signal.c code on sigreturn
 * handle TARGET_QEMU_ESIGRETURN in the main loop as the indication
   that the main loop should not touch any guest CPU state

Signed-off-by: Timothy Edward Baldwin <T.E.Baldwin99@members.leeds.ac.uk>
Message-id: 1441497448-32489-34-git-send-email-T.E.Baldwin99@members.leeds.ac.uk
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
[PMM: tweak commit message; drop TARGET_USE_ERESTARTSYS define]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
This commit is contained in:
Timothy E Baldwin 2016-05-12 18:47:41 +01:00 committed by Riku Voipio
parent 47405ab642
commit 6205086558
3 changed files with 7 additions and 2 deletions

View File

@ -26,4 +26,5 @@ static inline abi_ulong get_sp_from_cpustate(CPUCRISState *state)
return state->regs[14];
}
#endif /* TARGET_SIGNAL_H */

View File

@ -2914,7 +2914,11 @@ void cpu_loop(CPUCRISState *env)
env->pregs[7],
env->pregs[11],
0, 0);
env->regs[10] = ret;
if (ret == -TARGET_ERESTARTSYS) {
env->pc -= 2;
} else if (ret != -TARGET_QEMU_ESIGRETURN) {
env->regs[10] = ret;
}
break;
case EXCP_DEBUG:
{

View File

@ -3785,7 +3785,7 @@ long do_sigreturn(CPUCRISState *env)
restore_sigcontext(&frame->sc, env);
unlock_user_struct(frame, frame_addr, 0);
return env->regs[10];
return -TARGET_QEMU_ESIGRETURN;
badframe:
force_sig(TARGET_SIGSEGV);
}