You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
115 lines
3.0 KiB
115 lines
3.0 KiB
/* nbd-client.c - network block device client
|
|
*
|
|
* Copyright 2010 Rob Landley <rob@landley.net>
|
|
*
|
|
* Not in SUSv4.
|
|
|
|
// This little dance is because a NEWTOY with - in the name tries to do
|
|
// things like prototype "nbd-client_main" which isn't a valid symbol. So
|
|
// we hide the underscore name and OLDTOY the name we want.
|
|
USE_NBD_CLIENT(NEWTOY(nbd_client, "<3>3ns", 0))
|
|
USE_NBD_CLIENT(OLDTOY(nbd-client, nbd_client, TOYFLAG_USR|TOYFLAG_BIN))
|
|
|
|
config NBD_CLIENT
|
|
bool "nbd-client"
|
|
depends on TOYBOX_FORK
|
|
default y
|
|
help
|
|
usage: nbd-client [-ns] HOST PORT DEVICE
|
|
|
|
-n Do not fork into background
|
|
-s nbd swap support (lock server into memory)
|
|
*/
|
|
|
|
/* TODO:
|
|
usage: nbd-client [-sSpn] [-b BLKSZ] [-t SECS] [-N name] HOST PORT DEVICE
|
|
|
|
-b block size
|
|
-t timeout in seconds
|
|
-S sdp
|
|
-p persist
|
|
-n nofork
|
|
-d DEVICE
|
|
-c DEVICE
|
|
*/
|
|
|
|
#define FOR_nbd_client
|
|
#include "toys.h"
|
|
#include <linux/nbd.h>
|
|
|
|
void nbd_client_main(void)
|
|
{
|
|
int sock = -1, nbd, flags;
|
|
unsigned long timeout = 0;
|
|
char *host=toys.optargs[0], *port=toys.optargs[1], *device=toys.optargs[2];
|
|
uint64_t devsize;
|
|
|
|
// Repeat until spanked
|
|
|
|
nbd = xopen(device, O_RDWR);
|
|
for (;;) {
|
|
int temp;
|
|
|
|
// Find and connect to server
|
|
|
|
sock = xconnectany(xgetaddrinfo(host, port, AF_UNSPEC, SOCK_STREAM, 0, 0));
|
|
temp = 1;
|
|
setsockopt(sock, IPPROTO_TCP, TCP_NODELAY, &temp, sizeof(int));
|
|
|
|
// Read login data
|
|
|
|
xreadall(sock, toybuf, 152);
|
|
if (memcmp(toybuf, "NBDMAGIC\x00\x00\x42\x02\x81\x86\x12\x53", 16))
|
|
error_exit("bad login %s:%s", host, port);
|
|
devsize = SWAP_BE64(*(uint64_t *)(toybuf+16));
|
|
flags = SWAP_BE32(*(int *)(toybuf+24));
|
|
|
|
// Set 4k block size. Everything uses that these days.
|
|
ioctl(nbd, NBD_SET_BLKSIZE, 4096);
|
|
ioctl(nbd, NBD_SET_SIZE_BLOCKS, devsize/4096);
|
|
ioctl(nbd, NBD_CLEAR_SOCK);
|
|
|
|
// If the sucker was exported read only, respect that locally.
|
|
temp = (flags & 2) ? 1 : 0;
|
|
xioctl(nbd, BLKROSET, &temp);
|
|
|
|
if (timeout && ioctl(nbd, NBD_SET_TIMEOUT, timeout)<0) break;
|
|
if (ioctl(nbd, NBD_SET_SOCK, sock) < 0) break;
|
|
|
|
if (toys.optflags & FLAG_s) mlockall(MCL_CURRENT|MCL_FUTURE);
|
|
|
|
// Open the device to force reread of the partition table.
|
|
if ((toys.optflags & FLAG_n) || !xfork()) {
|
|
char *s = strrchr(device, '/');
|
|
int i;
|
|
|
|
sprintf(toybuf, "/sys/block/%.32s/pid", s ? s+1 : device);
|
|
// Is it up yet? (Give it 10 seconds.)
|
|
for (i=0; i<100; i++) {
|
|
temp = open(toybuf, O_RDONLY);
|
|
if (temp == -1) msleep(100);
|
|
else {
|
|
close(temp);
|
|
break;
|
|
}
|
|
}
|
|
close(open(device, O_RDONLY));
|
|
if (!(toys.optflags & FLAG_n)) exit(0);
|
|
}
|
|
|
|
// Daemonize here.
|
|
|
|
if (daemon(0,0)) perror_exit("daemonize");
|
|
|
|
// Process NBD requests until further notice.
|
|
|
|
if (ioctl(nbd, NBD_DO_IT)>=0 || errno==EBADR) break;
|
|
close(sock);
|
|
}
|
|
|
|
// Flush queue and exit.
|
|
ioctl(nbd, NBD_CLEAR_QUE);
|
|
ioctl(nbd, NBD_CLEAR_SOCK);
|
|
if (CFG_TOYBOX_FREE) close(nbd);
|
|
}
|