On 9:05 24/06, Christoph Hellwig wrote: > On Fri, Jun 21, 2019 at 02:28:25PM -0500, Goldwyn Rodrigues wrote: > > From: Goldwyn Rodrigues <rgoldwyn@xxxxxxxx> > > > > btrfs uses page->private as well to store extent_buffer. Make > > the check stricter to make sure we are using page->private for iop by > > comparing iblocksize < PAGE_SIZE. > > > > Signed-off-by: Goldwyn Rodrigues <rgoldwyn@xxxxxxxx> > > If btrfs uses page->private itself and also uses functions that call > to_iomap_page we have a major problem, as we now have a usage conflict. > > How do you end up here? > Btrfs uses page->private to identify which extent_buffer it belongs to. So, if you read, it fills the page->private. Then you try to write to it, iomap will assume it to be iomap_page pointer. I don't think we can move extent_buffer out of page->private for btrfs. Any other ideas? -- Goldwyn