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indirect EFS extent question

To: linux@cthulhu.engr.sgi.com (Linux/SGI list)
Subject: indirect EFS extent question
From: Mike Shaver <shaver@neon.ingenia.ca>
Date: Thu, 18 Sep 1997 14:48:28 -0400 (EDT)
Sender: owner-linux@cthulhu.engr.sgi.com
I just read the comment in fs/efs_fs.h properly for the first time,
and things are now much clearer.  I think.

So, is _this_ correct?
        /* 
         * We're indirect, so we need to start looking in the 
         * indirect extents.
         *
         * EFS indirect extents are really doubly indirect:
         * inode->di_u.di_extents (1st level extents) refers to
         * contiguous blocks of extents (2nd level extents).  The
         * block of these 2nd level extents contain direct extents (or
         * 3rd level extents).  So, for each indirect extent in
         * di_u.di_extents, we need to get a block of 2nd-level
         * extents, get a block from one of the 2nd-level extents, and
         * then check the extents in that final block -- which, at
         * long last, contains direct extents.
         */

Mike

-- 
#> Mike Shaver (shaver@ingenia.com) Ingenia Communications Corporation 
#>      Chief System Architect -- will tame sendmail(8) for food       
#>                                                                     
#> "You are a very perverse individual, and I think I'd like to get to 
#>  know you better." --- eric@reference.com                           

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