Hi David, I proceeded to parse the on-disk free blocks BTree for finding the free blocks information. Is there a way I could force a flush of BTree information to disk, so that in an online filesystem that is being changed I can also handle the changes in the BTree? I was looking at XFS_FSOP_GOING_FLAGS_LOGFLUSH flag but it might do more then I need to do and actually shutdown the filesystem. Any other options? I don't mind about performance degradation so interested in any option. Thanks, Ben -----Original Message----- From: Dave Chinner [mailto:david@xxxxxxxxxxxxx] Sent: Wednesday, April 27, 2016 7:41 PM To: Benjamin Wirth Cc: xfs@xxxxxxxxxxx Subject: Re: development APIs for used/free blocks information On Wed, Apr 27, 2016 at 12:54:24PM +0000, Benjamin Wirth wrote: > Hello Dave, > > Thanks for your response. > > And I apologize, reading back my email I wasn't clear about what I was > looking for. > > I want to be able to query which blocks are free or used, not just the > counts. In EXT I was able to use ext2fs_test_block_bitmap() for that. > XFS has a BTree with the free extents ordered by block number which I > was hoping to be able to access from user-space, but couldn't find any > APIs for it (or the headers containing the structure definitions) in > the xfsprogs-devel package. Am I trying to do something impossible > here? There are prototypes that need a bit of polishing to complete: http://oss.sgi.com/archives/xfs/2016-04/msg00633.html Cheers, Dave. -- Dave Chinner david@xxxxxxxxxxxxx _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
