Re: [GIT PULL] Filesystem Information

On Mon, Aug 3, 2020 at 5:50 PM David Howells [off-list ref] wrote:

Hi Linus,

Here's a set of patches that adds a system call, fsinfo(), that allows
information about the VFS, mount topology, superblock and files to be
retrieved.

The patchset is based on top of the mount notifications patchset so that
the mount notification mechanism can be hooked to provide event counters
that can be retrieved with fsinfo(), thereby making it a lot faster to work
out which mounts have changed.

Note that there was a last minute change requested by Miklós: the event
counter bits got moved from the mount notification patchset to this one.
The counters got made atomic_long_t inside the kernel and __u64 in the
UAPI.  The aggregate changes can be assessed by comparing pre-change tag,
fsinfo-core-20200724 to the requested pull tag.

Karel Zak has created preliminary patches that add support to libmount[*]
and Ian Kent has started working on making systemd use these and mount
notifications[**].

So why are you asking to pull at this stage?

Has anyone done a review of the patchset?

I think it's obvious that this API needs more work.  The integration
work done by Ian is a good direction, but it's not quite the full
validation and review that a complex new API needs.

At least that's my opinion.

Thanks,
Miklos