rbd-nbd: polish the doc and help information.

Signed-off-by: Pan Liu <liupan1111@gmail.com>

doc/man/8/rbd-nbd.rst

@@ -30,7 +30,7 @@ Options
 
 .. option:: --read-only
 
-   Map readonly.
+   Map read-only.
 
 .. option:: --nbds_max *limit*
 
@@ -43,7 +43,7 @@ Options
 
 .. option:: --exclusive
 
-   Forbid other clients write.
+   Forbid writes by other clients.
 
 Image and snap specs
 ====================

src/test/cli/rbd/help.t

@@ -1131,8 +1131,8 @@
     -p [ --pool ] arg     pool name
     --image arg           image name
     --snap arg            snapshot name
-    --read-only           mount read-only
-    --exclusive           forbid other clients write
+    --read-only           map read-only
+    --exclusive           forbid writes by other clients
     --device arg          specify nbd device
     --nbds_max arg        override module param nbds_max
     --max_part arg        override module param max_part

src/tools/rbd/action/Nbd.cc

@@ -99,8 +99,8 @@ void get_map_arguments(po::options_description *positional,
   at::add_image_or_snap_spec_options(positional, options,
                                      at::ARGUMENT_MODIFIER_NONE);
   options->add_options()
-    ("read-only", po::bool_switch(), "mount read-only")
-    ("exclusive", po::bool_switch(), "forbid other clients write")
+    ("read-only", po::bool_switch(), "map read-only")
+    ("exclusive", po::bool_switch(), "forbid writes by other clients")
     ("device", po::value<std::string>(), "specify nbd device")
     ("nbds_max", po::value<std::string>(), "override module param nbds_max")
     ("max_part", po::value<std::string>(), "override module param max_part");

src/tools/rbd_nbd/rbd-nbd.cc

@@ -64,10 +64,10 @@ static void usage()
             << "               list-mapped                         List mapped nbd devices\n"
             << "Options:\n"
             << "  --device <device path>  Specify nbd device path\n"
-            << "  --read-only             Map readonly\n"
+            << "  --read-only             Map read-only\n"
             << "  --nbds_max <limit>      Override for module param nbds_max\n"
             << "  --max_part <limit>      Override for module param max_part\n"
-            << "  --exclusive             Forbid other clients write\n"
+            << "  --exclusive             Forbid writes by other clients\n"
             << std::endl;
   generic_server_usage();
 }