int main(int argc, char **argv)
{
BlockDriverState *bs;
off_t dev_offset = 0;
off_t offset = 0;
bool readonly = false;
bool disconnect = false;
const char *bindto = "0.0.0.0";
int port = NBD_DEFAULT_PORT;
struct sockaddr_in addr;
socklen_t addr_len = sizeof(addr);
off_t fd_size;
char *device = NULL;
char *socket = NULL;
char sockpath[128];
const char *sopt = "hVb:o:p:rsnP:c:dvk:e:t";
struct option lopt[] = {
{ "help", 0, NULL, 'h' },
{ "version", 0, NULL, 'V' },
{ "bind", 1, NULL, 'b' },
{ "port", 1, NULL, 'p' },
{ "socket", 1, NULL, 'k' },
{ "offset", 1, NULL, 'o' },
{ "read-only", 0, NULL, 'r' },
{ "partition", 1, NULL, 'P' },
{ "connect", 1, NULL, 'c' },
{ "disconnect", 0, NULL, 'd' },
{ "snapshot", 0, NULL, 's' },
{ "nocache", 0, NULL, 'n' },
{ "shared", 1, NULL, 'e' },
{ "persistent", 0, NULL, 't' },
{ "verbose", 0, NULL, 'v' },
{ NULL, 0, NULL, 0 }
};
int ch;
int opt_ind = 0;
int li;
char *end;
int flags = BDRV_O_RDWR;
int partition = -1;
int ret;
int shared = 1;
uint8_t *data;
fd_set fds;
int *sharing_fds;
int fd;
int i;
int nb_fds = 0;
int max_fd;
int persistent = 0;
uint32_t nbdflags;
while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) {
switch (ch) {
case 's':
flags |= BDRV_O_SNAPSHOT;
break;
case 'n':
flags |= BDRV_O_NOCACHE;
break;
case 'b':
bindto = optarg;
break;
case 'p':
li = strtol(optarg, &end, 0);
if (*end) {
errx(EXIT_FAILURE, "Invalid port `%s'", optarg);
}
if (li < 1 || li > 65535) {
errx(EXIT_FAILURE, "Port out of range `%s'", optarg);
}
port = (uint16_t)li;
break;
case 'o':
dev_offset = strtoll (optarg, &end, 0);
if (*end) {
errx(EXIT_FAILURE, "Invalid offset `%s'", optarg);
}
if (dev_offset < 0) {
errx(EXIT_FAILURE, "Offset must be positive `%s'", optarg);
}
break;
case 'r':
readonly = true;
flags &= ~BDRV_O_RDWR;
break;
case 'P':
partition = strtol(optarg, &end, 0);
if (*end)
errx(EXIT_FAILURE, "Invalid partition `%s'", optarg);
if (partition < 1 || partition > 8)
errx(EXIT_FAILURE, "Invalid partition %d", partition);
break;
case 'k':
socket = optarg;
if (socket[0] != '/')
errx(EXIT_FAILURE, "socket path must be absolute\n");
break;
case 'd':
disconnect = true;
break;
case 'c':
device = optarg;
break;
case 'e':
shared = strtol(optarg, &end, 0);
if (*end) {
errx(EXIT_FAILURE, "Invalid shared device number '%s'", optarg);
}
if (shared < 1) {
errx(EXIT_FAILURE, "Shared device number must be greater than 0\n");
}
break;
case 't':
persistent = 1;
break;
case 'v':
verbose = 1;
break;
case 'V':
version(argv[0]);
exit(0);
break;
case 'h':
usage(argv[0]);
exit(0);
break;
case '?':
errx(EXIT_FAILURE, "Try `%s --help' for more information.",
argv[0]);
}
}
if ((argc - optind) != 1) {
errx(EXIT_FAILURE, "Invalid number of argument.\n"
"Try `%s --help' for more information.",
argv[0]);
}
if (disconnect) {
fd = open(argv[optind], O_RDWR);
if (fd == -1)
err(EXIT_FAILURE, "Cannot open %s", argv[optind]);
nbd_disconnect(fd);
close(fd);
printf("%s disconnected\n", argv[optind]);
return 0;
}
bdrv_init();
bs = bdrv_new("hda");
if (bs == NULL)
return 1;
if ((ret = bdrv_open(bs, argv[optind], flags, NULL)) < 0) {
errno = -ret;
err(EXIT_FAILURE, "Failed to bdrv_open '%s'", argv[optind]);
}
fd_size = bs->total_sectors * 512;
if (partition != -1 &&
find_partition(bs, partition, &dev_offset, &fd_size))
err(EXIT_FAILURE, "Could not find partition %d", partition);
if (device) {
pid_t pid;
int sock;
/* want to fail before daemonizing */
if (access(device, R_OK|W_OK) == -1) {
err(EXIT_FAILURE, "Could not access '%s'", device);
}
if (!verbose) {
/* detach client and server */
if (daemon(0, 0) == -1) {
err(EXIT_FAILURE, "Failed to daemonize");
}
}
if (socket == NULL) {
snprintf(sockpath, sizeof(sockpath), SOCKET_PATH,
basename(device));
socket = sockpath;
}
pid = fork();
if (pid < 0)
return 1;
if (pid != 0) {
off_t size;
size_t blocksize;
ret = 0;
bdrv_close(bs);
do {
sock = unix_socket_outgoing(socket);
if (sock == -1) {
if (errno != ENOENT && errno != ECONNREFUSED) {
ret = 1;
goto out;
}
sleep(1); /* wait children */
}
} while (sock == -1);
fd = open(device, O_RDWR);
if (fd == -1) {
ret = 1;
goto out;
}
ret = nbd_receive_negotiate(sock, NULL, &nbdflags,
&size, &blocksize);
if (ret == -1) {
ret = 1;
goto out;
}
ret = nbd_init(fd, sock, size, blocksize);
if (ret == -1) {
ret = 1;
goto out;
}
printf("NBD device %s is now connected to file %s\n",
device, argv[optind]);
/* update partition table */
show_parts(device);
ret = nbd_client(fd);
if (ret) {
ret = 1;
}
close(fd);
out:
kill(pid, SIGTERM);
unlink(socket);
return ret;
}
/* children */
}
sharing_fds = qemu_malloc((shared + 1) * sizeof(int));
if (socket) {
sharing_fds[0] = unix_socket_incoming(socket);
} else {
sharing_fds[0] = tcp_socket_incoming(bindto, port);
}
if (sharing_fds[0] == -1)
return 1;
max_fd = sharing_fds[0];
nb_fds++;
data = qemu_blockalign(bs, NBD_BUFFER_SIZE);
if (data == NULL)
errx(EXIT_FAILURE, "Cannot allocate data buffer");
do {
FD_ZERO(&fds);
for (i = 0; i < nb_fds; i++)
FD_SET(sharing_fds[i], &fds);
ret = select(max_fd + 1, &fds, NULL, NULL, NULL);
if (ret == -1)
break;
if (FD_ISSET(sharing_fds[0], &fds))
ret--;
for (i = 1; i < nb_fds && ret; i++) {
if (FD_ISSET(sharing_fds[i], &fds)) {
if (nbd_trip(bs, sharing_fds[i], fd_size, dev_offset,
&offset, readonly, data, NBD_BUFFER_SIZE) != 0) {
close(sharing_fds[i]);
nb_fds--;
sharing_fds[i] = sharing_fds[nb_fds];
i--;
}
ret--;
}
}
/* new connection ? */
if (FD_ISSET(sharing_fds[0], &fds)) {
if (nb_fds < shared + 1) {
sharing_fds[nb_fds] = accept(sharing_fds[0],
(struct sockaddr *)&addr,
&addr_len);
if (sharing_fds[nb_fds] != -1 &&
nbd_negotiate(sharing_fds[nb_fds], fd_size) != -1) {
if (sharing_fds[nb_fds] > max_fd)
max_fd = sharing_fds[nb_fds];
nb_fds++;
}
}
}
} while (persistent || nb_fds > 1);
qemu_vfree(data);
close(sharing_fds[0]);
bdrv_close(bs);
qemu_free(sharing_fds);
if (socket)
unlink(socket);
return 0;
}
int main(int argc, char **argv)
{
BlockDriverState *bs;
off_t dev_offset = 0;
off_t offset = 0;
uint32_t nbdflags = 0;
bool disconnect = false;
const char *bindto = "0.0.0.0";
int port = NBD_DEFAULT_PORT;
struct sockaddr_in addr;
socklen_t addr_len = sizeof(addr);
off_t fd_size;
const char *sopt = "hVb:o:p:rsnP:c:dvk:e:t";
struct option lopt[] = {
{ "help", 0, NULL, 'h' },
{ "version", 0, NULL, 'V' },
{ "bind", 1, NULL, 'b' },
{ "port", 1, NULL, 'p' },
{ "socket", 1, NULL, 'k' },
{ "offset", 1, NULL, 'o' },
{ "read-only", 0, NULL, 'r' },
{ "partition", 1, NULL, 'P' },
{ "connect", 1, NULL, 'c' },
{ "disconnect", 0, NULL, 'd' },
{ "snapshot", 0, NULL, 's' },
{ "nocache", 0, NULL, 'n' },
{ "shared", 1, NULL, 'e' },
{ "persistent", 0, NULL, 't' },
{ "verbose", 0, NULL, 'v' },
{ NULL, 0, NULL, 0 }
};
int ch;
int opt_ind = 0;
int li;
char *end;
int flags = BDRV_O_RDWR;
int partition = -1;
int ret;
int shared = 1;
uint8_t *data;
fd_set fds;
int *sharing_fds;
int fd;
int i;
int nb_fds = 0;
int max_fd;
int persistent = 0;
pthread_t client_thread;
/* The client thread uses SIGTERM to interrupt the server. A signal
* handler ensures that "qemu-nbd -v -c" exits with a nice status code.
*/
struct sigaction sa_sigterm;
int sigterm_fd[2];
if (qemu_pipe(sigterm_fd) == -1) {
err(EXIT_FAILURE, "Error setting up communication pipe");
}
sigterm_wfd = sigterm_fd[1];
memset(&sa_sigterm, 0, sizeof(sa_sigterm));
sa_sigterm.sa_handler = termsig_handler;
sigaction(SIGTERM, &sa_sigterm, NULL);
while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) {
switch (ch) {
case 's':
flags |= BDRV_O_SNAPSHOT;
break;
case 'n':
flags |= BDRV_O_NOCACHE | BDRV_O_CACHE_WB;
break;
case 'b':
bindto = optarg;
break;
case 'p':
li = strtol(optarg, &end, 0);
if (*end) {
errx(EXIT_FAILURE, "Invalid port `%s'", optarg);
}
if (li < 1 || li > 65535) {
errx(EXIT_FAILURE, "Port out of range `%s'", optarg);
}
port = (uint16_t)li;
break;
case 'o':
dev_offset = strtoll (optarg, &end, 0);
if (*end) {
errx(EXIT_FAILURE, "Invalid offset `%s'", optarg);
}
if (dev_offset < 0) {
errx(EXIT_FAILURE, "Offset must be positive `%s'", optarg);
}
break;
case 'r':
nbdflags |= NBD_FLAG_READ_ONLY;
flags &= ~BDRV_O_RDWR;
break;
case 'P':
partition = strtol(optarg, &end, 0);
if (*end)
errx(EXIT_FAILURE, "Invalid partition `%s'", optarg);
if (partition < 1 || partition > 8)
errx(EXIT_FAILURE, "Invalid partition %d", partition);
break;
case 'k':
sockpath = optarg;
if (sockpath[0] != '/')
errx(EXIT_FAILURE, "socket path must be absolute\n");
break;
case 'd':
disconnect = true;
break;
case 'c':
device = optarg;
break;
case 'e':
shared = strtol(optarg, &end, 0);
if (*end) {
errx(EXIT_FAILURE, "Invalid shared device number '%s'", optarg);
}
if (shared < 1) {
errx(EXIT_FAILURE, "Shared device number must be greater than 0\n");
}
break;
case 't':
persistent = 1;
break;
case 'v':
verbose = 1;
break;
case 'V':
version(argv[0]);
exit(0);
break;
case 'h':
usage(argv[0]);
exit(0);
break;
case '?':
errx(EXIT_FAILURE, "Try `%s --help' for more information.",
argv[0]);
}
}
if ((argc - optind) != 1) {
errx(EXIT_FAILURE, "Invalid number of argument.\n"
"Try `%s --help' for more information.",
argv[0]);
}
if (disconnect) {
fd = open(argv[optind], O_RDWR);
if (fd == -1)
err(EXIT_FAILURE, "Cannot open %s", argv[optind]);
nbd_disconnect(fd);
close(fd);
printf("%s disconnected\n", argv[optind]);
return 0;
}
if (device && !verbose) {
int stderr_fd[2];
pid_t pid;
int ret;
if (qemu_pipe(stderr_fd) == -1) {
err(EXIT_FAILURE, "Error setting up communication pipe");
}
/* Now daemonize, but keep a communication channel open to
* print errors and exit with the proper status code.
*/
pid = fork();
if (pid == 0) {
close(stderr_fd[0]);
ret = qemu_daemon(0, 0);
/* Temporarily redirect stderr to the parent's pipe... */
dup2(stderr_fd[1], STDERR_FILENO);
if (ret == -1) {
err(EXIT_FAILURE, "Failed to daemonize");
}
/* ... close the descriptor we inherited and go on. */
close(stderr_fd[1]);
} else {
bool errors = false;
char *buf;
/* In the parent. Print error messages from the child until
* it closes the pipe.
*/
close(stderr_fd[1]);
buf = g_malloc(1024);
while ((ret = read(stderr_fd[0], buf, 1024)) > 0) {
errors = true;
ret = qemu_write_full(STDERR_FILENO, buf, ret);
if (ret == -1) {
exit(EXIT_FAILURE);
}
}
if (ret == -1) {
err(EXIT_FAILURE, "Cannot read from daemon");
}
/* Usually the daemon should not print any message.
* Exit with zero status in that case.
*/
exit(errors);
}
}
if (device) {
/* Open before spawning new threads. In the future, we may
* drop privileges after opening.
*/
fd = open(device, O_RDWR);
if (fd == -1) {
err(EXIT_FAILURE, "Failed to open %s", device);
}
if (sockpath == NULL) {
sockpath = g_malloc(128);
snprintf(sockpath, 128, SOCKET_PATH, basename(device));
}
}
bdrv_init();
atexit(bdrv_close_all);
bs = bdrv_new("hda");
srcpath = argv[optind];
if ((ret = bdrv_open(bs, srcpath, flags, NULL)) < 0) {
errno = -ret;
err(EXIT_FAILURE, "Failed to bdrv_open '%s'", argv[optind]);
}
fd_size = bs->total_sectors * 512;
if (partition != -1 &&
find_partition(bs, partition, &dev_offset, &fd_size)) {
err(EXIT_FAILURE, "Could not find partition %d", partition);
}
sharing_fds = g_malloc((shared + 1) * sizeof(int));
if (sockpath) {
sharing_fds[0] = unix_socket_incoming(sockpath);
} else {
sharing_fds[0] = tcp_socket_incoming(bindto, port);
}
if (sharing_fds[0] == -1)
return 1;
if (device) {
int ret;
ret = pthread_create(&client_thread, NULL, nbd_client_thread, &fd);
if (ret != 0) {
errx(EXIT_FAILURE, "Failed to create client thread: %s",
strerror(ret));
}
} else {
/* Shut up GCC warnings. */
memset(&client_thread, 0, sizeof(client_thread));
}
max_fd = sharing_fds[0];
nb_fds++;
data = qemu_blockalign(bs, NBD_BUFFER_SIZE);
if (data == NULL) {
errx(EXIT_FAILURE, "Cannot allocate data buffer");
}
do {
FD_ZERO(&fds);
FD_SET(sigterm_fd[0], &fds);
for (i = 0; i < nb_fds; i++)
FD_SET(sharing_fds[i], &fds);
do {
ret = select(max_fd + 1, &fds, NULL, NULL, NULL);
} while (ret == -1 && errno == EINTR);
if (ret == -1 || FD_ISSET(sigterm_fd[0], &fds)) {
break;
}
if (FD_ISSET(sharing_fds[0], &fds))
ret--;
for (i = 1; i < nb_fds && ret; i++) {
if (FD_ISSET(sharing_fds[i], &fds)) {
if (nbd_trip(bs, sharing_fds[i], fd_size, dev_offset,
&offset, nbdflags, data, NBD_BUFFER_SIZE) != 0) {
close(sharing_fds[i]);
nb_fds--;
sharing_fds[i] = sharing_fds[nb_fds];
i--;
}
ret--;
}
}
/* new connection ? */
if (FD_ISSET(sharing_fds[0], &fds)) {
if (nb_fds < shared + 1) {
sharing_fds[nb_fds] = accept(sharing_fds[0],
(struct sockaddr *)&addr,
&addr_len);
if (sharing_fds[nb_fds] != -1 &&
nbd_negotiate(sharing_fds[nb_fds], fd_size, nbdflags) != -1) {
if (sharing_fds[nb_fds] > max_fd)
max_fd = sharing_fds[nb_fds];
nb_fds++;
}
}
}
} while (persistent || nb_fds > 1);
qemu_vfree(data);
close(sharing_fds[0]);
g_free(sharing_fds);
if (sockpath) {
unlink(sockpath);
}
if (device) {
void *ret;
pthread_join(client_thread, &ret);
exit(ret != NULL);
} else {
exit(EXIT_SUCCESS);
}
}
