[PATCH] block documentation updates

o Add 'tag' to request.txt doc
o Add bio design etc discussions

Documentation/block/request.txt

 
 struct request documentation
 
-Jens Axboe <axboe@suse.de> 070102
+Jens Axboe <axboe@suse.de> 27/05/02
 
 1.0
 Index
@@ -69,6 +69,8 @@ unsigned int current_nr_sectors	DB	Number of sectors in first segment
 
 unsigned int hard_cur_sectors	B	Used to keep current_nr_sectors sane
 
+int tag				DB	TCQ tag, if assigned
+
 void *special			D	Free to be used by driver
 
 char *buffer			D	Map of first segment, also see