// SPDX-License-Identifier: GPL-2.0

/*
 * Copyright 2015, Laurent Dufour, IBM Corp.
 *
 * Test the kernel's signal returning code to check reclaim is done if the
 * sigreturn() is called while in a transaction (suspended since active is
 * already dropped trough the system call path).
 *
 * The kernel must discard the transaction when entering sigreturn, since
 * restoring the potential TM SPRS from the signal frame is requiring to not be
 * in a transaction.
 */

#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>

#include "tm.h"
#include "utils.h"


void handler(int sig)
{
        uint64_t ret;

        asm __volatile__(
                "li             3,1             ;"
                "tbegin.                        ;"
                "beq            1f              ;"
                "li             3,0             ;"
                "tsuspend.                      ;"
                "1:                             ;"
                "std%X[ret]     3, %[ret]       ;"
                : [ret] "=m"(ret)
                :
                : "memory", "3", "cr0");

        if (ret)
                exit(1);

        /*
         * We return from the signal handle while in a suspended transaction
         */
}


int tm_sigreturn(void)
{
        struct sigaction sa;
        uint64_t ret = 0;

        SKIP_IF(!have_htm());
        SKIP_IF(htm_is_synthetic());
        SKIP_IF(!is_ppc64le());

        memset(&sa, 0, sizeof(sa));
        sa.sa_handler = handler;
        sigemptyset(&sa.sa_mask);

        if (sigaction(SIGSEGV, &sa, NULL))
                exit(1);

        asm __volatile__(
                "tbegin.                        ;"
                "beq            1f              ;"
                "li             3,0             ;"
                "std            3,0(3)          ;" /* trigger SEGV */
                "li             3,1             ;"
                "std%X[ret]     3,%[ret]        ;"
                "tend.                          ;"
                "b              2f              ;"
                "1:                             ;"
                "li             3,2             ;"
                "std%X[ret]     3,%[ret]        ;"
                "2:                             ;"
                : [ret] "=m"(ret)
                :
                : "memory", "3", "cr0");

        if (ret != 2)
                exit(1);

        exit(0);
}

int main(void)
{
        return test_harness(tm_sigreturn, "tm_sigreturn");
}