From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id B3A92CF6 for ; Wed, 24 Jul 2019 11:28:17 +0000 (UTC) Received: from mail-pf1-f172.google.com (mail-pf1-f172.google.com [209.85.210.172]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 5F3CC7F8 for ; Wed, 24 Jul 2019 11:28:17 +0000 (UTC) Received: by mail-pf1-f172.google.com with SMTP id q10so20799905pff.9 for ; Wed, 24 Jul 2019 04:28:17 -0700 (PDT) From: Sergey Senozhatsky Date: Wed, 24 Jul 2019 20:28:12 +0900 To: Amir Goldstein Message-ID: <20190724112812.GB496@tigerII.localdomain> References: <20190530055947.GA29812@mit.edu> <20190724055226.GA15444@jagdpanzerIV> <20190724080347.GA12744@jagdpanzerIV> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Cc: ksummit-discuss@lists.linuxfoundation.org Subject: Re: [Ksummit-discuss] [TECH TOPIC] Linux kernel SMB server (CIFSD) List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On (07/24/19 13:50), Amir Goldstein wrote: [..] > I don't see a problem with exporting those symbols. > As a matter of fact, I have a plan to use them also from overlayfs. > At the time that Jeff posted his patches, there was no active fsnotify > maintainer. Cool. > Jeff, did you abandon this effort for nfsd? > > > > > I even looked at LSM hooks, because they do what we need - invoke > > creat, open, truncate, chmod, chown, unlink, callbacks. But, first, > > I do realize that LSM was not meant to be used as some sort of fsnotify > > replacement, and, second, LSM symbols are not exported anyway :) > > > > fsnotify could actually be called from LSM hooks, see: > https://github.com/amir73il/linux/commits/fsnotify_dirent_perm > > It may or may not be clear to you, but what you get extra from fsnotify > compared to using bare LSM hooks is: Oh yeah, LSM does not really fit. I looked at it just out of curiosity. > - Minimal performance overhead for a non-marked object > - Ability to subscribe/unsubscribe to certain events dynamically Absolutely, we need to "subscribe/unsubscribe dynamically". > - Manage multiple subscriber instances (groups), like one per SMB session We need this as well, you're right. > - Queuing infrastructure for async events if you need it -ss