source: mainline/uspace/app/tester/mm/pager1.c@ d776329b

/*
 * Copyright (c) 2016 Jakub Jermar
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <stdlib.h>
#include <malloc.h>
#include <as.h>
#include <ns.h>
#include <async.h>
#include <errno.h>
#include "../tester.h"

#define TEST_FILE       "/tmp/testfile"

const char text[] = "Hello world!";

int fd;

static void *create_paged_area(size_t size)
{
        TPRINTF("Creating temporary file...\n");

        fd = open(TEST_FILE, O_CREAT);
        if (fd < 0)
                return NULL;
        (void) unlink(TEST_FILE);
        if (write(fd, text, sizeof(text)) != sizeof(text)) {
                close(fd);
                return NULL;
        }

        async_sess_t *vfs_pager_sess;

        TPRINTF("Connecting to VFS pager...\n");

        vfs_pager_sess = service_connect_blocking(SERVICE_VFS, INTERFACE_PAGER, 0);

        if (!vfs_pager_sess) {
                close(fd);
                return NULL;
        }
        
        TPRINTF("Creating AS area...\n");
        
        void *result = async_as_area_create(AS_AREA_ANY, size,
            AS_AREA_READ | AS_AREA_CACHEABLE, vfs_pager_sess, fd, 0, 0);
        if (result == AS_MAP_FAILED) {
                close(fd);
                return NULL;
        }
        
        return result;
}

static void touch_area(void *area, size_t size)
{
        TPRINTF("Touching (faulting-in) AS area...\n");
        
        volatile char *ptr = (char *) area;
        
        char ch;
        while ((ch = *ptr++))
                putchar(ch);
}

const char *test_pager1(void)
{
        size_t buffer_len = PAGE_SIZE;
        void *buffer = create_paged_area(buffer_len);
        if (!buffer)
                return "Cannot allocate memory";
        
        touch_area(buffer, buffer_len);

        as_area_destroy(buffer);        
        close(fd);
        
        return NULL;
}