54 lines
1.1 KiB
C
54 lines
1.1 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Copyright (C) 2024 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
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*/
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#include <assert.h>
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#include <stdbool.h>
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#include <stdint.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <unistd.h>
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#include <signal.h>
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#include <sys/mman.h>
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#include <linux/mman.h>
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#include "../kselftest.h"
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int main(int argc, char *argv[])
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{
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size_t alloc_size = 134217728;
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size_t page_size = getpagesize();
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void *alloc;
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pid_t child;
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ksft_print_header();
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ksft_set_plan(1);
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alloc = mmap(0, alloc_size, PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_DROPPABLE, -1, 0);
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assert(alloc != MAP_FAILED);
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memset(alloc, 'A', alloc_size);
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for (size_t i = 0; i < alloc_size; i += page_size)
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assert(*(uint8_t *)(alloc + i));
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child = fork();
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assert(child >= 0);
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if (!child) {
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for (;;)
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*(char *)malloc(page_size) = 'B';
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}
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for (bool done = false; !done;) {
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for (size_t i = 0; i < alloc_size; i += page_size) {
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if (!*(uint8_t *)(alloc + i)) {
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done = true;
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break;
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}
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}
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}
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kill(child, SIGTERM);
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ksft_test_result_pass("MAP_DROPPABLE: PASS\n");
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exit(KSFT_PASS);
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}
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