/*

* Author: Kent Overstreet <kmo@daterainc.com>

*

* GPLv2

*/

#define _FILE_OFFSET_BITS 64

#define _XOPEN_SOURCE 500

#define _GNU_SOURCE

#include <fcntl.h>

#include <limits.h>

#include <linux/fs.h>

#include <math.h>

#include <stdbool.h>

#include <stdio.h>

#include <string.h>

#include <unistd.h>

#include <sys/ioctl.h>

#include <sys/klog.h>

#include <sys/param.h>

#include <sys/types.h>

#include <sys/stat.h>

#include <stdlib.h>

#include <stdint.h>

#include <time.h>

#include <openssl/rc4.h>

#include <openssl/md4.h>

static const unsigned char bcache_magic[] = {

0xc6, 0x85, 0x73, 0xf6, 0x4e, 0x1a, 0x45, 0xca,

0x82, 0x65, 0xf5, 0x7f, 0x48, 0xba, 0x6d, 0x81 };

unsigned char zero[4096];

bool klog = false;

#define Pread(fd, buf, size, offset) do { \

int _read = 0, _r; \

while (_read < size) { \

_r = pread(fd, buf, (size) - _read, (offset) + _read); \

if (_r <= 0) \

goto err; \

_read += _r; \

} \

} while (0)

#define Pwrite(fd, buf, size, offset) do { \

int _write = 0, _r; \

while (_write < size) { \

_r = pwrite(fd, buf, (size) - _write, offset + _write); \

if (_r < 0) \

goto err; \

_write += _r; \

} \

} while (0)

/* Marsaglia polar method

*/

double normal()

{

double x, y, s;

static double n = 0 / (double) 0;

if (n == n) {

x = n;

n = 0 / (double) 0;

return x;

}

do {

x = random() / (double) (RAND_MAX / 2) - 1;

y = random() / (double) (RAND_MAX / 2) - 1;

s = x * x + y * y;

} while (s >= 1);

s = sqrt(-2 * log(s) / s);

n = y * s;

return x * s;

}

long getblocks(int fd)

{

long ret;

struct stat statbuf;

if (fstat(fd, &statbuf)) {

perror("stat error");

exit(EXIT_FAILURE);

}

ret = statbuf.st_size / 512;

if (S_ISBLK(statbuf.st_mode))

if (ioctl(fd, BLKGETSIZE, &ret)) {

perror("ioctl error");

exit(EXIT_FAILURE);

}

return ret;

}

struct pagestuff {

};

void flushlog(void)

{

char logbuf[1 << 21];

int w = 0, len;

static int fd;

if (!klog)

return;

if (!fd) {

klogctl(8, 0, 6);

sprintf(logbuf, "log.%i", abs(random()) % 1000);

fd = open(logbuf, O_WRONLY|O_CREAT|O_TRUNC, 0644);

if (fd == -1) {

perror("Error opening log file");

exit(EXIT_FAILURE);

}

}

len = klogctl(4, logbuf, 1 << 21);

if (len == -1) {

perror("Error reading kernel log");

exit(EXIT_FAILURE);

}

while (w < len) {

int r = write(fd, logbuf + w, len - w);

if (r == -1) {

perror("Error writing log");

exit(EXIT_FAILURE);

}

w += r;

}

}

void aio_loop(int nr)

{

}

void usage()

{

exit(EXIT_FAILURE);

}

int main(int argc, char **argv)

{

bool walk = false, randsize = false, verbose = false, csum = false, rtest = false, wtest = false;

int fd1, fd2 = 0, direct = 0, nbytes = 4096, j, o;

unsigned long size, i, offset = 0, done = 0, unique = 0, benchmark = 0;

void *buf1 = NULL, *buf2 = NULL;

struct pagestuff *pages, *p;

unsigned char c[16];

time_t last_printed = 0;

extern char *optarg;

RC4_KEY writedata;

RC4_set_key(&writedata, 16, bcache_magic);

while ((o = getopt(argc, argv, "dnwvscwlb:")) != EOF)

switch (o) {

case 'd':

direct = O_DIRECT;

break;

case 'n':

walk = true;

break;

case 'v':

verbose = true;

break;

case 's':

randsize = true;

break;

case 'c':

csum = true;

break;

case 'w':

wtest = true;

break;

case 'r':

rtest = true;

break;

case 'l':

klog = true;

break;

case 'b':

benchmark = atol(optarg);

break;

default:

usage();

}

argv += optind;

argc -= optind;

if (!rtest && !wtest)

rtest = true;

if (argc < 1) {

printf("Please enter a device to test\n");

exit(EXIT_FAILURE);

}

if (!csum && !benchmark && argc < 2) {

printf("Please enter a device to compare against\n");

exit(EXIT_FAILURE);

}

fd1 = open(argv[0], (wtest ? O_RDWR : O_RDONLY)|direct);

if (!csum && !benchmark)

fd2 = open(argv[1], (wtest ? O_RDWR : O_RDONLY)|direct);

if (fd1 == -1 || fd2 == -1) {

perror("Error opening device");

exit(EXIT_FAILURE);

}

size = getblocks(fd1);

if (!csum && !benchmark)

size = MIN(size, getblocks(fd2));

size = size / 8 - 16;

pages = calloc(size + 16, sizeof(*pages));

printf("size %li\n", size);

if (posix_memalign(&buf1, 4096, 4096 * 16) ||

posix_memalign(&buf2, 4096, 4096 * 16)) {

printf("Could not allocate buffers\n");

exit(EXIT_FAILURE);

}

//setvbuf(stdout, NULL, _IONBF, 0);

for (i = 0; !benchmark || i < benchmark; i++) {

bool writing = (wtest && (i & 1)) || !rtest;

nbytes = randsize ? drand48() * 16 + 1 : 1;

nbytes <<= 12;

offset >>= 12;

offset += walk ? normal() * 20 : random();

offset %= size;

offset <<= 12;

if (!(i % 200))

flushlog();

if (!verbose) {

time_t now = time(NULL);

if (now - last_printed >= 2) {

last_printed = now;

goto print;

}

} else

print: printf("Loop %6li offset %9li sectors %3i, %6lu mb done, %6lu mb unique\n",

i, offset >> 9, nbytes >> 9, done >> 11, unique >> 11);

done += nbytes >> 9;

if (!writing)

Pread(fd1, buf1, nbytes, offset);

if (!writing && !csum && !benchmark)

Pread(fd2, buf2, nbytes, offset);

for (j = 0; j < nbytes; j += 4096) {

p = &pages[(offset + j) / 4096];

if (writing)

RC4(&writedata, 4096, zero, buf1 + j);

if (csum) {

MD4(buf1 + j, 4096, &c[0]);

if (writing ||

(!p->readcount && !p->writecount)) {

memcpy(&p->oldcsum[0], &p->csum[0], 16);

memcpy(&p->csum[0], c, 16);

} else if (memcmp(&p->csum[0], c, 16))

goto bad;

} else if (!writing && !benchmark &&

memcmp(buf1 + j,

buf2 + j,

4096))

goto bad;

if (!p->writecount && !p->readcount)

unique += 8;

writing ? p->writecount++ : p->readcount++;

}

if (writing)

Pwrite(fd1, buf1, nbytes, offset);

if (writing && !csum && !benchmark)

Pwrite(fd2, buf2, nbytes, offset);

}

printf("Loop %6li offset %9li sectors %3i, %6lu mb done, %6lu mb unique\n",

i, offset >> 9, nbytes >> 9, done >> 11, unique >> 11);

exit(EXIT_SUCCESS);

err:

perror("IO error");

flushlog();

exit(EXIT_FAILURE);

bad:

printf("Bad read! loop %li offset %li readcount %i writecount %i\n",

i, (offset + j) >> 9, p->readcount, p->writecount);

if (!memcmp(&p->oldcsum[0], c, 16))

printf("Matches previous csum\n");

flushlog();

exit(EXIT_FAILURE);

}