-static int
-zfs_create_unique_device(dev_t *dev)
-{
- major_t new_major;
-
- do {
- ASSERT3U(zfs_minor, <=, MAXMIN32);
- minor_t start = zfs_minor;
- do {
- mutex_enter(&zfs_dev_mtx);
- if (zfs_minor >= MAXMIN32) {
- /*
- * If we're still using the real major
- * keep out of /dev/zfs and /dev/zvol minor
- * number space. If we're using a getudev()'ed
- * major number, we can use all of its minors.
- */
- if (zfs_major == ddi_name_to_major(ZFS_DRIVER))
- zfs_minor = ZFS_MIN_MINOR;
- else
- zfs_minor = 0;
- } else {
- zfs_minor++;
- }
- *dev = makedevice(zfs_major, zfs_minor);
- mutex_exit(&zfs_dev_mtx);
- } while (vfs_devismounted(*dev) && zfs_minor != start);
- if (zfs_minor == start) {
- /*
- * We are using all ~262,000 minor numbers for the
- * current major number. Create a new major number.
- */
- if ((new_major = getudev()) == (major_t)-1) {
- cmn_err(CE_WARN,
- "zfs_mount: Can't get unique major "
- "device number.");
- return (-1);
- }
- mutex_enter(&zfs_dev_mtx);
- zfs_major = new_major;
- zfs_minor = 0;
-
- mutex_exit(&zfs_dev_mtx);
- } else {
- break;
- }
- /* CONSTANTCONDITION */
- } while (1);
-
- return (0);
-}
-