@@ -400,7 +400,7 @@ static int nbd_setup(void)
int main(int argc, char **argv)
{
- const char *sopt = "hVb:o:p:rsnP:c:dvk:e:t";
+ const char *sopt = "hVb:o:p:rsnP:c:dvk:e:tf";
struct option lopt[] = {
{ "help", 0, NULL, 'h' },
{ "version", 0, NULL, 'V' },
@@ -417,12 +417,14 @@ int main(int argc, char **argv)
{ "shared", 1, NULL, 'e' },
{ "persistent", 0, NULL, 't' },
{ "verbose", 0, NULL, 'v' },
+ { "find", 0, NULL, 'f' },
{ NULL, 0, NULL, 0 }
};
int ch;
int opt_ind = 0;
char *end;
int ret = 0;
+ int find = 0;
/* The client thread uses SIGTERM to interrupt the server. A signal
* handler ensures that "qemu-nbd -v -c" exits with a nice status code.
@@ -491,6 +493,9 @@ int main(int argc, char **argv)
case 'c':
device = optarg;
break;
+ case 'f':
+ find = 1;
+ break;
case 'e':
shared = strtol(optarg, &end, 0);
if (*end) {
@@ -541,7 +546,7 @@ int main(int argc, char **argv)
return 0;
}
- if (device && !verbose) {
+ if ((device || find) && !verbose) {
int stderr_fd[2];
pid_t pid;
@@ -596,7 +601,21 @@ int main(int argc, char **argv)
atexit(bdrv_close_all);
srcpath = argv[optind];
- ret = nbd_setup();
+ if (!find) {
+ ret = nbd_setup();
+ } else {
+ int max_nbd = 16;
+ int i;
+ for (i = 0; i < max_nbd; i++) {
+ if (!asprintf(&device, "/dev/nbd%d", i))
+ continue;
+ ret = nbd_setup();
+ if (ret != EXIT_SUCCESS) {
+ free(device);
+ continue;
+ }
+ }
+ }
exit(ret);
}
Add -f option to qemu-nbd so that it can find a free nbd device and connect disk.img to that device. Changes to v3: a. According to Stefan's suggestion, loop over /dev/nbd%d to do "qemu-nbd -f disk.img", if fails, try next device. b. syntax "qemu-nbd -f disk.img" only Signed-off-by: Chunyan Liu <cyliu@suse.com> --- qemu-nbd.c | 25 ++++++++++++++++++++++--- 1 files changed, 22 insertions(+), 3 deletions(-)