// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Ptrace test for TAR, PPR, DSCR registers
 *
 * Copyright (C) 2015 Anshuman Khandual, IBM Corporation.
 */
#include "ptrace.h"
#include "ptrace-tar.h"

/* Tracer and Tracee Shared Data */
int shm_id;
int *cptr;
int *pptr;

void tar(void)
{
        unsigned long reg[3];
        int ret;

        cptr = (int *)shmat(shm_id, NULL, 0);
        printf("%-30s TAR: %u PPR: %lx DSCR: %u\n",
                        user_write, TAR_1, PPR_1, DSCR_1);

        mtspr(SPRN_TAR, TAR_1);
        mtspr(SPRN_PPR, PPR_1);
        mtspr(SPRN_DSCR, DSCR_1);

        cptr[2] = 1;

        /* Wait on parent */
        while (!cptr[0])
                asm volatile("" : : : "memory");

        reg[0] = mfspr(SPRN_TAR);
        reg[1] = mfspr(SPRN_PPR);
        reg[2] = mfspr(SPRN_DSCR);

        printf("%-30s TAR: %lu PPR: %lx DSCR: %lu\n",
                        user_read, reg[0], reg[1], reg[2]);

        /* Unblock the parent now */
        cptr[1] = 1;
        shmdt((int *)cptr);

        ret = validate_tar_registers(reg, TAR_2, PPR_2, DSCR_2);
        if (ret)
                exit(1);
        exit(0);
}

int trace_tar(pid_t child)
{
        unsigned long reg[3];

        FAIL_IF(start_trace(child));
        FAIL_IF(show_tar_registers(child, reg));
        printf("%-30s TAR: %lu PPR: %lx DSCR: %lu\n",
                        ptrace_read_running, reg[0], reg[1], reg[2]);

        FAIL_IF(validate_tar_registers(reg, TAR_1, PPR_1, DSCR_1));
        FAIL_IF(stop_trace(child));
        return TEST_PASS;
}

int trace_tar_write(pid_t child)
{
        FAIL_IF(start_trace(child));
        FAIL_IF(write_tar_registers(child, TAR_2, PPR_2, DSCR_2));
        printf("%-30s TAR: %u PPR: %lx DSCR: %u\n",
                        ptrace_write_running, TAR_2, PPR_2, DSCR_2);

        FAIL_IF(stop_trace(child));
        return TEST_PASS;
}

int ptrace_tar(void)
{
        pid_t pid;
        int ret, status;

        // TAR was added in v2.07
        SKIP_IF_MSG(!have_hwcap2(PPC_FEATURE2_ARCH_2_07), "TAR requires ISA 2.07 compatible hardware");

        shm_id = shmget(IPC_PRIVATE, sizeof(int) * 3, 0777|IPC_CREAT);
        pid = fork();
        if (pid < 0) {
                perror("fork() failed");
                return TEST_FAIL;
        }

        if (pid == 0)
                tar();

        if (pid) {
                pptr = (int *)shmat(shm_id, NULL, 0);
                pptr[0] = 0;
                pptr[1] = 0;

                while (!pptr[2])
                        asm volatile("" : : : "memory");
                ret = trace_tar(pid);
                if (ret)
                        return ret;

                ret = trace_tar_write(pid);
                if (ret)
                        return ret;

                /* Unblock the child now */
                pptr[0] = 1;

                /* Wait on child */
                while (!pptr[1])
                        asm volatile("" : : : "memory");

                shmdt((int *)pptr);

                ret = wait(&status);
                shmctl(shm_id, IPC_RMID, NULL);
                if (ret != pid) {
                        printf("Child's exit status not captured\n");
                        return TEST_PASS;
                }

                return (WIFEXITED(status) && WEXITSTATUS(status)) ? TEST_FAIL :
                        TEST_PASS;
        }
        return TEST_PASS;
}

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