Re: [PATCH 1/5] repair: handle repair of image files on large sector size filesystems

[Christoph Hellwig <hch@xxxxxxxxxxxxx>]

On Mon, Oct 10, 2011 at 11:17:08AM +1100, Dave Chinner wrote:
> > Does it?  Given that the loop driver uses buffered I/O that would be
> > unexpected behaviour.  I'll try to reproduce it as soon as my 4k
> > disk is available again.
> 
> My 3TB, RAID6 based image storage filesystem has a 4k sector size,
> and I can't run xfs_repair on an image file that has smaller sector
> sizes than 4k without this mod. In that case, xfs_repair is doing
> direct IO on a file, not a device, and the file is on the 4k sector
> sized filesytem. I've been carrying this patch for a while.

Got it - you repair the image on directly on the device, without the
loop driver.