// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright 2016, Chris Smart, IBM Corporation.
 *
 * Calls to copy_first which are not 128-byte aligned should be
 * caught and sent a SIGBUS.
 */

#include <signal.h>
#include <string.h>
#include <unistd.h>
#include "utils.h"
#include "instructions.h"

unsigned int expected_instruction = PPC_INST_COPY_FIRST;
unsigned int instruction_mask = 0xfc2007fe;

void signal_action_handler(int signal_num, siginfo_t *info, void *ptr)
{
        ucontext_t *ctx = ptr;
#ifdef __powerpc64__
        unsigned int *pc = (unsigned int *)ctx->uc_mcontext.gp_regs[PT_NIP];
#else
        unsigned int *pc = (unsigned int *)ctx->uc_mcontext.uc_regs->gregs[PT_NIP];
#endif

        /*
         * Check that the signal was on the correct instruction, using a
         * mask because the compiler assigns the register at RB.
         */
        if ((*pc & instruction_mask) == expected_instruction)
                _exit(0); /* We hit the right instruction */

        _exit(1);
}

void setup_signal_handler(void)
{
        struct sigaction signal_action;

        memset(&signal_action, 0, sizeof(signal_action));
        signal_action.sa_sigaction = signal_action_handler;
        signal_action.sa_flags = SA_SIGINFO;
        sigaction(SIGBUS, &signal_action, NULL);
}

char cacheline_buf[128] __cacheline_aligned;

int test_copy_first_unaligned(void)
{
        /* Only run this test on a P9 or later */
        SKIP_IF(!have_hwcap2(PPC_FEATURE2_ARCH_3_00));

        /* Register our signal handler with SIGBUS */
        setup_signal_handler();

        /* +1 makes buf unaligned */
        copy_first(cacheline_buf+1);

        /* We should not get here */
        return 1;
}

int main(int argc, char *argv[])
{
        return test_harness(test_copy_first_unaligned, "test_copy_first_unaligned");
}