[PATCH] xfs_db: improve the fsmap man page entry

[Christoph Hellwig <hch@lst.de>]

Improve documentation of the flags and optional arguments, and fix up
messed up formatting.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 man/man8/xfs_db.8 | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/man/man8/xfs_db.8 b/man/man8/xfs_db.8
index ba2a68211ef2..89db535d38c9 100644
--- a/man/man8/xfs_db.8
+++ b/man/man8/xfs_db.8
@@ -849,14 +849,24 @@ command to convert to and from this form. Block numbers given for file blocks
 .B bmap
 command) are in this form.
 .TP
-.BI "fsmap [ " start " ] [ " end " ]
+.BI "fsmap [\-r] [" start " [" end ]]
 Prints the mapping of disk blocks used by an XFS filesystem.  The map
 lists each extent used by files, allocation group metadata,
 journalling logs, and static filesystem metadata, as well as any
 regions that are unused.  All blocks, offsets, and lengths are specified
 in units of 512-byte blocks, no matter what the filesystem's block size is.
-.BI "The optional " start " and " end " arguments can be used to constrain
-the output to a particular range of disk blocks.
+.IP
+The optional
+.I start
+and
+.I end
+arguments can be used to constrain the output to a particular range of disk
+blocks.
+.IP
+When the
+.B \-r
+option is specified, prints the reverse mapping for the real-time device
+instead of the data device.
 .TP
 .BI "fuzz [\-c] [\-d] " "field action"
 Write garbage into a specific structure field on disk.
-- 
2.53.0