#losetup -l

losetup: invalid option -- 'l'
Usage:
 losetup loop_device                             give info
 losetup -a | --all                              list all used
 losetup -d | --detach <loopdev> [<loopdev> ...] delete
 losetup -f | --find                             find unused
 losetup -c | --set-capacity <loopdev>           resize
 losetup -j | --associated <file> [-o <num>]     list all associated with <file>
 losetup [ options ] {-f|--find|loopdev} <file>  setup
Options:
 -e | --encryption <type> enable data encryption with specified <name/num>
 -h | --help              this help
 -o | --offset <num>      start at offset <num> into file
      --sizelimit <num>   loop limited to only <num> bytes of the file
 -p | --pass-fd <num>     read passphrase from file descriptor <num>
 -r | --read-only         setup read-only loop device
      --show              print device name (with -f <file>)
 -N | --nohashpass        Do not hash the given password (Debian hashes)
 -k | --keybits <num>     specify number of bits in the hashed key given
                          to the cipher.  Some ciphers support several key
                          sizes and might be more efficient with a smaller
                          key size.  Key sizes < 128 are generally not
                          recommended
 -v | --verbose           verbose mode