/*
* zram: generic RAM based compressed R/W block devices
* http://lkml.org/lkml/2010/8/9/227
*
* Copyright (C) 2010 Red Hat, Inc.
* This program is free software; you can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public
* License as published by the Free Software Foundation.
*
* This program is distributed in the hope that it would be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
*
* Further, this software is distributed without any warranty that it
* is free of the rightful claim of any third person regarding
* infringement or the like. Any license provided herein, whether
* implied or otherwise, applies only to this software file. Patent
* licenses, if any, provided herein do not apply to combinations of
* this program with other software, or any other product whatsoever.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*/
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include "test.h"
#include "safe_macros.h"
char *TCID = "zram03";
int TST_TOTAL = 1;
#define PATH_ZRAM "/sys/block/zram0"
#define OBSOLETE_ZRAM_FILE "/sys/block/zram0/num_reads"
#define PATH_ZRAM_STAT "/sys/block/zram0/stat"
#define PATH_ZRAM_MM_STAT "/sys/block/zram0/mm_stat"
#define SIZE (512 * 1024 * 1024L)
#define DEVICE "/dev/zram0"
static int modprobe;
static void set_disksize(void);
static void write_device(void);
static void verify_device(void);
static void reset(void);
static void setup(void);
static void cleanup(void);
static void print(char *string);
static void dump_info(void);
int main(int argc, char *argv[])
{
int lc;
tst_parse_opts(argc, argv, NULL, NULL);
setup();
for (lc = 0; TEST_LOOPING(lc); lc++) {
tst_count = 0;
set_disksize();
write_device();
dump_info();
verify_device();
reset();
dump_info();
}
cleanup();
tst_exit();
}
static void set_disksize(void)
{
tst_resm(TINFO, "create a zram device with %ld bytes in size.", SIZE);
SAFE_FILE_PRINTF(cleanup, PATH_ZRAM "/disksize", "%ld", SIZE);
}
static void write_device(void)
{
int fd;
char *s;
tst_resm(TINFO, "map this zram device into memory.");
fd = SAFE_OPEN(cleanup, DEVICE, O_RDWR);
s = SAFE_MMAP(cleanup, NULL, SIZE, PROT_READ | PROT_WRITE,
MAP_SHARED, fd, 0);
tst_resm(TINFO, "write all the memory.");
memset(s, 'a', SIZE - 1);
s[SIZE - 1] = '\0';
SAFE_MUNMAP(cleanup, s, SIZE);
SAFE_CLOSE(cleanup, fd);
}
static void verify_device(void)
{
int fd;
long i = 0, fail = 0;
char *s;
tst_resm(TINFO, "verify contents from device.");
fd = SAFE_OPEN(cleanup, DEVICE, O_RDONLY);
s = SAFE_MMAP(cleanup, NULL, SIZE, PROT_READ, MAP_PRIVATE, fd, 0);
while (s[i] && i < SIZE - 1) {
if (s[i] != 'a')
fail++;
i++;
}
if (i != SIZE - 1) {
tst_resm(TFAIL, "expect size: %ld, actual size: %ld.",
SIZE - 1, i);
} else if (s[i] != '\0') {
tst_resm(TFAIL, "zram device seems not null terminated");
} else if (fail) {
tst_resm(TFAIL, "%ld failed bytes found.", fail);
} else {
tst_resm(TPASS, "data read from zram device is consistent "
"with those are written");
}
SAFE_MUNMAP(cleanup, s, SIZE);
SAFE_CLOSE(cleanup, fd);
}
static void reset(void)
{
tst_resm(TINFO, "reset it.");
SAFE_FILE_PRINTF(cleanup, PATH_ZRAM "/reset", "1");
}
static void setup(void)
{
int retried = 0;
tst_require_root();
retry:
if (access(PATH_ZRAM, F_OK) == -1) {
if (errno == ENOENT) {
if (retried) {
tst_brkm(TCONF, NULL,
"system has no zram device.");
}
if (system("modprobe zram") == -1) {
tst_brkm(TBROK | TERRNO, cleanup,
"system(modprobe zram) failed");
}
modprobe = 1;
retried = 1;
goto retry;
} else
tst_brkm(TBROK | TERRNO, NULL, "access");
}
tst_sig(FORK, DEF_HANDLER, cleanup);
TEST_PAUSE;
}
static void cleanup(void)
{
if (modprobe == 1 && system("rmmod zram") == -1)
tst_resm(TWARN | TERRNO, "system(rmmod zram) failed");
}
static void print(char *string)
{
char filename[BUFSIZ], value[BUFSIZ];
sprintf(filename, "%s/%s", PATH_ZRAM, string);
SAFE_FILE_SCANF(cleanup, filename, "%s", value);
tst_resm(TINFO, "%s is %s", filename, value);
}
static void print_stat(char *nread, char *nwrite)
{
char nread_val[BUFSIZ], nwrite_val[BUFSIZ];
SAFE_FILE_SCANF(cleanup, PATH_ZRAM_STAT, "%s %*s %*s %*s %s",
nread_val, nwrite_val);
tst_resm(TINFO, "%s from %s is %s", nread, PATH_ZRAM_STAT,
nread_val);
tst_resm(TINFO, "%s from %s is %s", nwrite, PATH_ZRAM_STAT,
nwrite_val);
}
static void print_mm_stat(char *orig, char *compr, char *mem, char *zero)
{
char orig_val[BUFSIZ], compr_val[BUFSIZ];
char mem_val[BUFSIZ], zero_val[BUFSIZ];
SAFE_FILE_SCANF(cleanup, PATH_ZRAM_MM_STAT, "%s %s %s %*s %*s %s",
orig_val, compr_val, mem_val, zero_val);
tst_resm(TINFO, "%s from %s is %s", orig, PATH_ZRAM_MM_STAT,
orig_val);
tst_resm(TINFO, "%s from %s is %s", compr, PATH_ZRAM_MM_STAT,
compr_val);
tst_resm(TINFO, "%s from %s is %s", mem, PATH_ZRAM_MM_STAT,
mem_val);
tst_resm(TINFO, "%s from %s is %s", zero, PATH_ZRAM_MM_STAT,
zero_val);
}
static void dump_info(void)
{
print("initstate");
print("disksize");
if (!access(OBSOLETE_ZRAM_FILE, F_OK)) {
print("orig_data_size");
print("compr_data_size");
print("mem_used_total");
print("zero_pages");
print("num_reads");
print("num_writes");
} else {
print_mm_stat("orig_data_size", "compr_data_size",
"mem_used_total", "zero/same_pages");
print_stat("num_reads", "num_writes");
}
}