#!/bin/bash
# SPDX-License-Identifier: GPL-2.0
#
# Copyright (C) 2022 Adam Sindelar (Meta) <adam@wowsignal.io>
#
# This is a test for mmap behavior with 5-level paging. This script wraps the
# real test to check that the kernel is configured to support at least 5
# pagetable levels.

# 1 means the test failed
exitcode=1

# Kselftest framework requirement - SKIP code is 4.
ksft_skip=4

die()
{
    echo "$1"
    exit $exitcode
}

check_test_requirements()
{
    local config="/proc/config.gz"
    [[ -f "${config}" ]] || config="/boot/config-$(uname -r)"
    [[ -f "${config}" ]] || die "Cannot find kernel config in /proc or /boot"

    # gzip -dcfq automatically handles both compressed and plaintext input.
    # See man 1 gzip under '-f'.
    local pg_table_levels=$(gzip -dcfq "${config}" | grep PGTABLE_LEVELS | cut -d'=' -f 2)

    if [[ "${pg_table_levels}" -lt 5 ]]; then
        echo "$0: PG_TABLE_LEVELS=${pg_table_levels}, must be >= 5 to run this test"
        exit $ksft_skip
    fi
}

check_test_requirements
./va_128TBswitch