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From:   Paulo Alcantara <pc@cjr.nz>
To:     Shyam Prasad N <nspmangalore@gmail.com>,
        Steve French <smfrench@gmail.com>,
        =?utf-8?Q?Aur=C3=A9lien?= Aptel <aaptel@suse.com>,
        CIFS <linux-cifs@vger.kernel.org>, sribhat.msa@outlook.com,
        rohiths msft <rohiths.msft@gmail.com>
Subject: Re: Multichannel patches
In-Reply-To: <CANT5p=oMLZei+OhXZ-8Hr2NCx=pRYWF1zQ0vRQ5D_NkvLGwJDg@mail.gmail.com>
References: <CANT5p=oMLZei+OhXZ-8Hr2NCx=pRYWF1zQ0vRQ5D_NkvLGwJDg@mail.gmail.com>
Date:   Wed, 02 Jun 2021 13:45:38 -0300
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Shyam Prasad N <nspmangalore@gmail.com> writes:

> P.S. There is a logic in cifs_reconnect to switch between the targets
> for the server. I don't think these changes will break the DFS
> scenario. The code will likely take effect only for when the primary
> channel reconnects (as DFS server entries are cached with super block
> as the key). Perhaps more changes will be needed there to also switch
> between the targets for individual channels (maybe use superblock +
> channel num as the key for caching entries?). Folks with better
> knowledge than me with this code may want to check on this?

I don't think your changes would break it as well.  The super is only
used for providing cifs_sb_info::origin_fullpath as key to find the
corresponding failover targets in referral cache.

I can help you testing your changes with some DFS+multichannel failover
scenarios.