btrfs-progs: check: update help text

Add some missing options and add a high-level description.

Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/cmds-check.c b/cmds-check.c
index fe51aae..1f8caad 100644 (file)
--- a/cmds-check.c
+++ b/cmds-check.c
@@ -9368,17 +9368,23 @@ out:
 
 const char * const cmd_check_usage[] = {
        "btrfs check [options] <device>",
-       "Check an unmounted btrfs filesystem.",
+       "Check structural inegrity of a filesystem (unmounted).",
+       "Check structural inegrity of an unmounted filesystem. Verify internal",
+       "trees' consistency and item connectivity. In the repair mode try to",
+       "fix the problems found.",
+       "WARNING: the repair mode is considered dangerous",
        "",
        "-s|--super <superblock>     use this superblock copy",
        "-b|--backup                 use the backup root copy",
        "--repair                    try to repair the filesystem",
+       "--readonly                  run in read-only mode (default)",
        "--init-csum-tree            create a new CRC tree",
        "--init-extent-tree          create a new extent tree",
        "--check-data-csum           verify checkums of data blocks",
-       "--qgroup-report             print a report on qgroup consistency",
-       "--subvol-extents <subvolid> print subvolume extents and sharing state",
-       "--tree-root <bytenr>        use the given bytenr for the tree root",
+       "-Q|--qgroup-report           print a report on qgroup consistency",
+       "-E|--subvol-extents <subvolid>",
+       "                            print subvolume extents and sharing state",
+       "-r|--tree-root <bytenr>     use the given bytenr for the tree root",
        "-p|--progress               indicate progress",
        NULL
 };