Ext4 Punch Hole v6 Change Summary

[Allison Henderson <achender@linux.vnet.ibm.com>]

Hi All,

Here is the latest copy of punch hole for ext4.  This copy has been 
modified to apply on top of Yongqiang's v2 patch set that revises the 
split extents routines.  So the patch that used to modify the split 
extents routines (patch 2/6 of punch hole v5) has been removed.  I have 
tested this combination of patch sets against the same tests I used for 
v5 and they all look good.  Thx Yongqiang for all your work :)

Some other things that changed between v5 and v6:

patch 1/5:
The flag that this patch adds has been changed to use new EXT4_MB flag 
instead of creating a new set of flags

patch 5/5:
New function "ext4_ext_check_cache" has been added.  It is similar to 
ext4_ext_in_cache but it accepts a ext4_ext_cache parameter instead of a 
ext4_extent.  After letting one of my test cases run overnight, I found 
a bug that was caused by the ext4_ext_in_cache routine trying to copy a 
ext4_ext_cache field into a ext4_extent field that was too small to 
contain it.  So the new ext4_ext_check_cache corrects this.

That's pretty much all of the changes between the sets.  As always feed 
back is appreciated.  Thx all!

Allison Henderson