testcases/kernel/io/ltp-aiodio/ltp-diorh.c

/*
 *   Copyright (C) 2003,2004 Red Hat, Inc.  All rights reserved.
 *
 *   The contents of this file may be used under the terms of the GNU
 *   General Public License version 2 (the "GPL")
 *
 *   Author: Stephen C. Tweedie <sct@redhat.com>
 *   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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 *
 * Module: .c
 */

/*
 * Change History:
 *
 * 2/2004  Marty Ridgeway (mridge@us.ibm.com) Changes to adapt to LTP
 *
 */

#define _XOPEN_SOURCE 600
#define _GNU_SOURCE
#define MAX_ITERATIONS 250

#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <sys/fcntl.h>
#include <sys/mman.h>
#include <sys/wait.h>

#define BIGSIZE 128*1024*1024
#define READSIZE 32*1024*1024
#define WRITESIZE 32*1024*1024

int pagesize;
char *iobuf;
int pass = 0;

void assert(const char *what, int assertion)
{
		 if (assertion)
		 		 return;
		 perror(what);
		 exit(1);
}

void do_buffered_writes(int fd, int pattern)
{
		 int rc;
		 int offset;

		 memset(iobuf, pattern, WRITESIZE);
		 for (offset = 0; offset+WRITESIZE <= BIGSIZE; offset += WRITESIZE) {
		 		 rc = pwrite(fd, iobuf, WRITESIZE, offset);
		 		 assert("pwrite", rc >= 0);
		 		 if (rc != WRITESIZE) {
		 		 		 fprintf(stderr, "Pass %d: short write (%d out of %d)\n",
		 		 		 		 pass, rc, WRITESIZE);
		 		 		 exit(1);
		 		 }
		 		 fsync(fd);
		 }
}

int do_direct_reads(char *filename)
{
		 int fd;
		 int offset;
		 int rc, i;
		 int *p;

		 fd = open(filename, O_DIRECT|O_RDONLY, 0);
		 assert("open", fd >= 0);

		 for (offset = 0; offset+READSIZE <= BIGSIZE; offset += READSIZE) {
		 		 rc = pread(fd, iobuf, READSIZE, offset);
		 		 assert("pread", rc >= 0);
		 		 if (rc != READSIZE) {
		 		 		 fprintf(stderr, "Pass: %d short read (%d out of %d)\n",
		 		 		 		 pass, rc, READSIZE);
		 		 		 exit(1);
		 		 }
		 		 for (i=0, p=(int *)iobuf; i<READSIZE; i+=4) {
		 		 		 if (*p) {
		 		 		 		 fprintf(stderr,
		 		 		 		 		 "Pass: %d Found data (%08x) at offset %d+%d\n",
		 		 		 		 		 pass, *p, offset, i);
                                 close(fd);
		 		 		 		 return 1;
		 		 		 }
		 		 		 p++;
		 		 }
		 }
		 close(fd);
		 return 0;
}

int main(int argc, char *argv[])
{
		 char *filename;
		 int fd;
		 int pid;
		 int err;
		 int bufsize;

		 if (argc != 2) {
		 		 fprintf(stderr, "Needs a filename as an argument.\n");
		 		 exit(1);
		 }

		 filename = argv[1];

		 pagesize = getpagesize();
		 bufsize = READSIZE;
		 if (WRITESIZE > READSIZE)
		 		 bufsize = WRITESIZE;
		 err = posix_memalign((void**) &iobuf, pagesize, bufsize);
		 if (err) {
		 		 fprintf(stderr, "Error allocating %d aligned bytes.\n", bufsize);
		 		 exit(1);
		 }

		 fd = open(filename, O_CREAT|O_TRUNC|O_RDWR, 0666);
		 assert("open", fd >= 0);

		 do {

		 		 assert("ftruncate", ftruncate(fd, BIGSIZE) == 0);
		 		 fsync(fd);

		 		 pid = fork();
		 		 assert("fork", pid >= 0);

		 		 if (!pid) {
		 		 		 do_buffered_writes(fd, 0);
		 		 		 exit(0);
		 		 }

		 		 err = do_direct_reads(filename);

		 		 wait4(pid, NULL, WNOHANG, 0);

		 		 if (err)
		 		 		 break;

		 		 /* Fill the file with a known pattern so that the blocks
		 		  * on disk can be detected if they become exposed. */
		 		 do_buffered_writes(fd, 1);
		 		 fsync(fd);

		 		 assert("ftruncate", ftruncate(fd, 0) == 0);
		 		 fsync(fd);
		 } while (pass++ < MAX_ITERATIONS);

         if (!err) {
             fprintf(stdout, "ltp-diorh: Completed %d iterations OK \n", pass);
         }

		 return err;
}