Re: [PATCH v2 0/5] btrfs: support fsverity

[Eric Biggers <ebiggers@kernel.org>]

On Fri, Mar 05, 2021 at 11:26:28AM -0800, Boris Burkov wrote:
> This patchset provides support for fsverity in btrfs.
> 
> At a high level, we store the verity descriptor and Merkle tree data
> in the file system btree with the file's inode as the objectid, and
> direct reads/writes to those items to implement the generic fsverity
> interface required by fs/verity/.
> 
> The first patch is a preparatory patch which adds a notion of
> compat_flags to the btrfs_inode and inode_item in order to allow
> enabling verity on a file without making the file system unmountable for
> older kernels. (It runs afoul of the leaf corruption check otherwise)
> 
> The second patch is the bulk of the fsverity implementation. It
> implements the fsverity interface and adds verity checks for the typical
> file reading case.
> 
> The third patch cleans up the corner cases in readpage, covering inline
> extents, preallocated extents, and holes.
> 
> The fourth patch handles direct io of a veritied file by falling back to
> buffered io.
> 
> The fifth patch handles crashes mid-verity enable via orphan items
> 

Can you include information about how this was tested?

Also, fsverity-utils works with btrfs as-is, correct?

- Eric