Re: [PATCH v3 11/35] iomap: allow filesystem to read fsverity metadata beyound EOF

[Christoph Hellwig <hch@lst.de>]

On Mon, Feb 23, 2026 at 04:10:23PM +0100, Andrey Albershteyn wrote:
> 
> > 
> > I'm still not sure what "When iomap is reading fsverity descriptor
> > inode" means.
> 
> "When iomap is reading fsverity descriptor, inode won't have any
> fsverity_info yet."

What code path is this?  __fsverity_file_open -> ensure_verity_info ->
fsverity_get_descriptor?

> > See above, unlike ext4/f2fs we set it for all I/O on fsverity inodes.
> > And afaik we don't actually need it, the only use in the fsverity
> > metadata path is the fill zeroes hash values check (which I'm still
> > totally confused about).
> 
> Yeah, for metadata the only use is to fill zero hash blocks. I will
> try to split it so lookup happens for data and holes in fsverity
> metadata. This way we would have less lookups for metadata.

I think doing one lookup per ->read_folio / ->readahead is fine.
I just really need to understand the differences here.  I think I'm
finally getting it, and it would be greast to capture all this in
comments.  I'll carefully read over the next versions and will suggest
updates to the comments based on the my understanding if needed.