Re: [PATCH] fiemap support for ext3

[Eric Sandeen <sandeen@redhat.com>]

Josef Bacik wrote:
> On Wed, Apr 23, 2008 at 08:58:03PM -0600, Andreas Dilger wrote:
>> On Apr 23, 2008  15:39 -0400, Josef Bacik wrote:
>>> Here is my reworked fiemap patch for ext3.  The generic fiemap handler
>>> takes the get_block_t from the filesystem and does the fiemap that way,
>>> so then adding ext2 support should be a snap, as well as any other fs
>>> that wants to use this.
>> Ah, one other point is that this should also be used by ext4 to map inodes
>> that are not in extents format, replacing the -EOPNOTSUPP return in that
>> case.
>>
> 
> Sounds good, but I'm wondering if we should add a flag to the FIEMAP stuff to
> specify wether the inode you are mapping does truly have extents or if its just
> more of a block map.  Do you think something like that would be usefull?  Thank
> you,
> 
> Josef 

I don't see that in itself as useful; you care about file layout, but
why would you care about the filesystem's mechanism for tracking that
layout?

-Eric