[LSF/MM TOPIC] [LSF/MM ATTEND] FS Management Interfaces

[Steven Whitehouse <swhiteho@redhat.com>]

Hi,

This is a request both to attend LSF/MM and also a topic proposal. The 
last couple of years I've proposed a topic of the block/fs interface. 
I'm happy to do that again, if there is consensus that this would be 
useful, however this time I thought that I'd propose something a bit 
different.

I had originally thought about calling the proposal "kernel/userland 
interface", however that seemed a bit vague and management interfaces 
seems like a better title since it is I hope a bit clearer of the kind 
of thing that I'm thinking about in this case.

There are a number of possible sub-topics and I hope that I might find a 
few more before LSF too. One is that of space management (we have 
statfs, but currently no notifications for thresholds crossed etc., so 
everything is polled. That is ok sometimes, but statfs can be expensive 
in the case of distributed filesystems, if 100% accurate. We could just 
have ENOSPC notifications for 100% full, or something more generic), 
another is state transitions (is the fs running normally, or has it gone 
read only/withdrawn/etc due to I/O errors?) and a further topic would be 
working towards a common interface for fs statistics (at the moment each 
fs defines their own interface). One potential implementation, at least 
for the first two sub-topics, would be to use something along the lines 
of the quota netlink interface, but since few ideas survive first 
contact with the community at large, I'm throwing this out for further 
discussion and feedback on whether this approach is considered the right 
way to go.

Assuming the topic is accepted, my intention would be to gather together 
some additional sub-topics relating to fs management to go along with 
those I mentioned above, and I'd be very interested to hear of any other 
issues that could be usefully added to the list for discussion.

My interest in other topics is fairly wide... I'm, as usual, interested 
in all filesystem related topics and a good number of block device and 
mm topics too. Anything relating to vfs, xfs, ext*, btrfs, gfs2, 
overlayfs, NFS/CIFS, and technologies such as copy-offload, DAX, 
reflink, RDMA, NVMe(F), etc.,

Steve.