Re: [Ksummit-discuss] [TECH TOPIC] Linux kernel SMB server (CIFSD)

[Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>]

Cc-ing Jan, Amir, Jeff

Hi!

On (05/30/19 01:59), Theodore Ts'o wrote:
> From: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
[..]
> CIFSD is a new SMB server implementation for the Linux kernel
> (out of tree, as of this moment), intended to be minimalistic,
> yet providing better performance than user-space analogues.
> This talk will briefly introduce CIFSD, its architecture (high
> level) and its main design goals: outline components, their
> responsibilities and communication protocols.
> 
> The work is still in progress, we are in pretty early stages,
> so in the second part of the talk we will focus on current state
> of affairs and our future development plans - we are looking at
> possibility to merge CIFSD with the upstream Linux kernel,
> sometime in the future.

To extend the topic with some discussion points:

- We are facing a rather familiar problem. Basically, SMB2 CHANGE_NOTIFY
  [1] is something what fsnotify normally does, except that we can't use
  it in cifsd kernel module. I see that NFS guys had [2] same issues some
  time ago.

  So the question is - how to do fs notify style monitoring in a kernel
  module (nfsd, cifsd)? Any chance the kernel can start exporting fsnotify
  symbols?

[1] https://docs.microsoft.com/en-us/openspecs/windows_protocols/ms-smb2/598f395a-e7a2-4cc8-afb3-ccb30dd2df7c
[2] https://lore.kernel.org/linux-fsdevel/1441968882-7851-5-git-send-email-jeff.layton@primarydata.com/

	-ss