[PATCH] improved filefrag output

[Andreas Dilger <adilger@xxxxxxx>]

Attached is a patch to improve the filefrag output.  The most  
important part of the change is that it allows the "extent format"  
output to be used even if the filesystem does not support FIEMAP.   
This is useful for older kernels (i.e. most vendor kernels), or in  
case FIEMAP hasn't been wired into a filesystem yet.

The extent format output is improved to be more similar to that of  
xfs_bmap, so it prints out a range of logical and physical block  
numbers, in addition to the extent length, so that it is easier to see  
where the discontinuities are.  There is also an option to print out  
the extents/lengths in hex, and using a different blocksize (e.g. "- 
b1M" to print in units of 1MB):

$ filefrag -e -b1M "Indiana Jones And The Temple Of Doom.avi"
 ext:     device_logical:        physical_offset: length: flags:
   0:        0..       1:     320566..    320567:      1:
   1:        1..       3:     320866..    320868:      2:
   2:        3..       3:     320768..    320768:      0:
   3:        4..      29:     320870..    320895:     26:
   4:       30..     155:     320898..    321023:    126:
   5:      156..     281:     321026..    321151:    126:
   6:      282..     407:     321154..    321279:    126:
   7:      408..     533:     321282..    321407:    126:
   8:      534..     659:     321410..    321535:    126:

Also included is support for FIEMAP extensions to support multi-device  
filesystems (e.g. Lustre, ZFS, maybe btrfs in the future).

Cheers, Andreas
--
Andreas Dilger
Sr. Staff Engineer, Lustre Group
Sun Microsystems of Canada, Inc.

Attachment: e2fsprogs-fiemap-lustre.patch
Description: Binary data