testcases/kernel/syscalls/bdflush/bdflush01.c

/******************************************************************************/
/* Copyright (c) Crackerjack Project., 2007				   */
/*									    */
/* 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    */
/*									    */
/******************************************************************************/
/******************************************************************************/
/*									    */
/* File:	bdflush01.c					    */
/*									    */
/* Description: bdflush() starts, flushes, or tunes the buffer-dirty-flush    */
/*		daemon. Only a privileged process (one with the CAP_SYS_ADMIN */
/*		capability) may call bdflush().				      */
/*									      */
/*		If func is negative or 0, and no daemon has been started,     */
/*		then bdflush() enters the daemon code and never returns.      */
/*									      */
/*		If func is 1, some dirty buffers are written to disk.	      */
/*		If func is 2 or more and is even (low bit is 0), then address */
/*		is the address of a long word, and the tuning parameter       */
/*		numbered (func-2)/2 is returned to the caller in that address.*/
/*									      */
/*		If func is 3 or more and is odd (low bit is 1), then data is  */
/*		a long word, and the kernel sets tuning parameter numbered    */
/*		(func-3)/2 to that value.				      */
/*		    							      */
/*		The set of parameters, their values, and their legal ranges   */
/*		are defined in the kernel source file fs/buffer.c. 	      */
/*									      */
/*		Return Value:						      */
/*		If func is negative or 0 and the daemon successfully starts,  */
/*		bdflush() never returns. Otherwise, the return value is 0 on  */
/*		success and -1 on failure, with errno set to indicate the     */
/*		error.							      */
/*									      */
/*		Errors:							      */
/*			EBUSY						      */
/*			    An attempt was made to enter the daemon code after*/
/*			    another process has already entered. 	      */
/*			EFAULT						      */
/*			   address points outside your accessible address     */
/*			   space. 					      */
/*			EINVAL						      */
/*			    An attempt was made to read or write an invalid   */
/*			    parameter number, or to write an invalid value to */
/*			    a parameter. 				      */
/*			EPERM						      */
/*			    Caller does not have the CAP_SYS_ADMIN capability.*/
/*									      */
/* Usage:  <for command-line>						 */
/* bdflush01 [-c n] [-e][-i n] [-I x] [-p x] [-t]		      */
/*      where,  -c n : Run n copies concurrently.			     */
/*	      -e   : Turn on errno logging.				 */
/*	      -i n : Execute test n times.				  */
/*	      -I x : Execute test for x seconds.			    */
/*	      -P x : Pause for x seconds between iterations.		*/
/*	      -t   : Turn on syscall timing.				*/
/*									    */
/* Total Tests: 1							     */
/*									    */
/* Test Name:   bdflush01					      */
/* History:     Porting from Crackerjack to LTP is done by		    */
/*	      Manas Kumar Nayak maknayak@in.ibm.com>			*/
/******************************************************************************/
#include <stdio.h>
#include <stdlib.h>
#include <sys/wait.h>
#include <sys/types.h>
#include <unistd.h>
#include <errno.h>
#include <sys/stat.h>

#include "test.h"
#include "usctest.h"
#include "linux_syscall_numbers.h"

char *TCID = "bdflush01";
int testno;
int TST_TOTAL = 1;

void cleanup(void)
{
	TEST_CLEANUP;
	tst_rmdir();
}

void setup(void)
{
	TEST_PAUSE;
	tst_tmpdir();
}

int main(int ac, char **av)
{
	long data;
	const char *msg;

	if ((msg = parse_opts(ac, av, NULL, NULL)) != NULL)
		tst_brkm(TBROK, cleanup, "OPTION PARSING ERROR - %s", msg);

	setup();

	/*
	 * TODO (garrcoop): add more functional testcases; there are a ton
	 * missing.
	 */
	data = 0;
	tst_count = 1;
	for (testno = 0; testno < TST_TOTAL; ++testno) {
		TEST(ltp_syscall(__NR_bdflush, 3, data));
		if (TEST_RETURN == -1)
			tst_brkm(TFAIL | TTERRNO, cleanup, "bdflush failed");
		else
			tst_resm(TPASS, "bdflush() = %ld", TEST_RETURN);
	}
	cleanup();
	tst_exit();
}