testcases/kernel/syscalls/mincore/mincore02.c

/*
 * Copyright (c) International Business Machines  Corp., 2001
 *   Author: Rajeev Tiwari: rajeevti@in.ibm.com
 * Copyright (c) 2004 Gernot Payer <gpayer@suse.de>
 * Copyright (c) 2013 Cyril Hrubis <chrubis@suse.cz>
 *
 * This program is free software;  you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY;  without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
 * the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program;  if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

/*
 * This test case provides a functional validation for mincore system call.
 * We mmap a file of known size (multiple of page size) and lock it in
 * memory. Then we obtain page location information via mincore and compare
 * the result with the expected value.
 */

#include <sys/mman.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <fcntl.h>
#include <unistd.h>
#include <signal.h>
#include <errno.h>

#include "test.h"

char *TCID = "mincore02";
int TST_TOTAL = 1;

static int fd = 0;
static void *addr = NULL;
static int page_size;
static int num_pages = 4;
static unsigned char *vec = NULL;

static void cleanup(void)
{
	free(vec);
	munlock(addr, page_size * num_pages);
	munmap(addr, page_size * num_pages);
	close(fd);
	tst_rmdir();
}

static void setup(void)
{
	char *buf;
	size_t size;

	tst_tmpdir();

	page_size = getpagesize();
	if (page_size == -1)
		tst_brkm(TBROK | TERRNO, cleanup, "Unable to get page size");

	size = page_size * num_pages;
	buf = malloc(size);

	memset(buf, 42, size);
	vec = malloc((size + page_size - 1) / page_size);
	
	fd = open("mincore02", O_CREAT | O_RDWR, S_IRUSR | S_IWUSR);
	if (fd == -1) {
		tst_brkm(TBROK | TERRNO, cleanup,
		         "Unable to create temporary file");
	}

	/* fill the temporary file with two pages of data */
	if (write(fd, buf, size) < 0) {
		tst_brkm(TBROK | TERRNO, cleanup,
		         "Error in writing to the file");
	}
	free(buf);

	addr = mmap(NULL, size, PROT_READ | PROT_WRITE | PROT_EXEC,
	            MAP_SHARED, fd, 0);

	if (addr == MAP_FAILED) {
		tst_brkm(TBROK | TERRNO, cleanup,
                         "Unable to map file for read/write");
	}

	/* lock mmapped file, so mincore returns "in core" for all pages */
	if (mlock(addr, size) == -1)
		tst_brkm(TBROK | TERRNO, cleanup, "Unable to lock the file");
}

int main(int argc, char **argv)
{
	int lock_pages, counter;
	const char *msg;
	int lc;

	msg = parse_opts(argc, argv, NULL, NULL);
	if (msg != NULL)
		tst_brkm(TBROK, cleanup, "error parsing options: %s", msg);

	setup();
	
	for (lc = 0; TEST_LOOPING(lc); lc++) {
		tst_count = 0;

		if (mincore(addr, num_pages * page_size, vec) == -1) {
			tst_brkm(TBROK | TERRNO, cleanup,
			         "Unable to execute mincore system call");
		}

		/* check status of pages */
		lock_pages = 0;

		for (counter = 0; counter < num_pages; counter++) {
			if (vec[counter] & 1)
				lock_pages++;
		}

		if (lock_pages == num_pages) {
			tst_resm(TPASS, "%d pages locked, %d pages in-core", num_pages,
				 lock_pages);
		} else {
			tst_resm(TFAIL,
				 "not all locked pages are in-core: no. locked: %d, no. in-core: %d",
				 num_pages, lock_pages);
		}
	}

	cleanup();
	tst_exit();
}