Re: [PATCH 00/19] VFS: Filesystem information and notifications [ver #16]

[Christian Brauner]

On Tue, Feb 18, 2020 at 05:04:55PM +0000, David Howells wrote:
> 
> Here are a set of patches that adds system calls, that (a) allow
> information about the VFS, mount topology, superblock and files to be
> retrieved and (b) allow for notifications of mount topology rearrangement
> events, mount and superblock attribute changes and other superblock events,
> such as errors.
> 
> ============================
> FILESYSTEM INFORMATION QUERY
> ============================
> 
> The first system call, fsinfo(), allows information about the filesystem at
> a particular path point to be queried as a set of attributes, some of which
> may have more than one value.
> 
> Attribute values are of four basic types:
> 
>  (1) Version dependent-length structure (size defined by type).
> 
>  (2) Variable-length string (up to 4096, including NUL).
> 
>  (3) List of structures (up to INT_MAX size).
> 
>  (4) Opaque blob (up to INT_MAX size).

I mainly have an organizational question. :) This is a huge patchset
with lots and lots of (good) features. Wouldn't it make sense to make
the fsinfo() syscall a completely separate patchset from the
watch_mount() and watch_sb() syscalls? It seems that they don't need to
depend on each other at all. This would make reviewing this so much
nicer and likely would mean that fsinfo() could proceed a little faster.

Christian