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From: Bharath SM <bharathsm.hsk@gmail.com>
To: rajasimandalos@gmail.com
Cc: sfrench@samba.org, linux-cifs@vger.kernel.org,
	 Rajasi Mandal <rajasimandal@microsoft.com>
Subject: Re: [PATCH v2] smb: client: allow nolease option to be reconfigured on remount
Date: Wed, 22 Apr 2026 01:36:39 -0700	[thread overview]
Message-ID: <CAGypqWz-rThJ3SaeJECy9mG3e+CCmozkns5k3UyatdVuXSonjw@mail.gmail.com> (raw)
In-Reply-To: <20260422050613.1136327-1-rajasimandalos@gmail.com>

On Tue, Apr 21, 2026 at 10:06 PM <rajasimandalos@gmail.com> wrote:
>
> From: Rajasi Mandal <rajasimandal@microsoft.com>
>
> tcon->no_lease controls whether the client requests leases from the
> server.  Changing nolease via remount is silently accepted but has
> no effect because the value is never propagated to the live tcon.
>
> Add no_lease to smb3_sync_tcon_opts() so the flag is propagated to
> every tcon on remount.
>
> When switching to nolease, close all deferred file handles via
> cifs_close_all_deferred_files_sb() outside the tlink_tree_lock,
> since closing deferred handles can sleep.  Deferred handles retain
> active leases from before the switch; without closing them, those
> files continue using lease-based caching despite nolease being set.
>
> Both transitions are safe:
>  - lease -> nolease: deferred handles are closed, future opens
>    get OPLOCK_LEVEL_NONE.
>  - nolease -> lease: future opens request leases normally.
>
> Signed-off-by: Rajasi Mandal <rajasimandal@microsoft.com>
> ---
>  fs/smb/client/fs_context.c | 9 +++++++++
>  1 file changed, 9 insertions(+)
>
> diff --git a/fs/smb/client/fs_context.c b/fs/smb/client/fs_context.c
> index 45173f287f00..fb59b45c7f66 100644
> --- a/fs/smb/client/fs_context.c
> +++ b/fs/smb/client/fs_context.c
> @@ -1317,6 +1317,7 @@ static void smb3_sync_tcon_opts(struct cifs_sb_info *cifs_sb,
>
>                 spin_lock(&tcon->tc_lock);
>                 tcon->retry = ctx->retry;
> +               tcon->no_lease = ctx->no_lease;
>                 /*
>                  * Note: this updates the limit for new cached dir opens
>                  * but does not resize or evict existing cached dirents.
> @@ -1325,6 +1326,14 @@ static void smb3_sync_tcon_opts(struct cifs_sb_info *cifs_sb,
>                 spin_unlock(&tcon->tc_lock);
>         }
>         spin_unlock(&cifs_sb->tlink_tree_lock);
> +
> +       /*
> +        * When switching to nolease, close all deferred file handles.
> +        * cifs_close_all_deferred_files_sb() handles its own locking
> +        * and must be called outside tlink_tree_lock since it can sleep.
> +        */
> +       if (ctx->no_lease)
> +               cifs_close_all_deferred_files_sb(cifs_sb);
>  }
Similar to deferred files, I think we probably need to invalidate the
cached directory
entries when we remount with 'nolease' considering 'nolease' is a
superset mount option
and should affect all types of leases.

One additional case to consider: if an application already has a file
open with an RWH
lease acquired before the remount, that handle may continue to hold
its lease and benefit
from caching until the server sends a lease break or the application
closes the handle.
Is that correct.?
I think nolease remount only affects new opens; it cannot
retroactively revoke leases on
existing active file handles. It may be worth documenting and/or
comment this behavior,
so it's clear that lease->nolease takes effect gradually as old
handles are closed rather than
instantaneously across all files & handles.

Other than these comments, change looks good to me.

  reply	other threads:[~2026-04-22  8:36 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-04-09  9:59 [PATCH 1/9] smb: client: block non-reconfigurable option changes on remount rajasimandalos
2026-04-09  9:59 ` [PATCH 2/9] smb: client: allow both 'lease' and 'nolease' mount options rajasimandalos
2026-04-13 13:30   ` Meetakshi Setiya
2026-04-09  9:59 ` [PATCH 3/9] smb: client: sync tcon-level options on remount rajasimandalos
2026-04-17 14:29   ` Meetakshi Setiya
2026-04-09  9:59 ` [PATCH 4/9] smb: client: sync retrans " rajasimandalos
2026-04-09  9:59 ` [PATCH 5/9] smb: client: sync echo_interval " rajasimandalos
2026-04-22  4:42   ` [PATCH v2] " rajasimandalos
2026-04-09  9:59 ` [PATCH 6/9] smb: client: allow nolease option to be reconfigured " rajasimandalos
2026-04-22  5:06   ` [PATCH v2] " rajasimandalos
2026-04-22  8:36     ` Bharath SM [this message]
2026-04-22 15:29       ` Steve French
2026-04-09  9:59 ` [PATCH 7/9] smb: client: block cache=ro and cache=singleclient " rajasimandalos
2026-04-13 13:40   ` Meetakshi Setiya
2026-04-22  4:34     ` RAJASI MANDAL
2026-04-09  9:59 ` [PATCH 8/9] smb: client: fix domainauto remount by syncing domainname from session rajasimandalos
2026-04-09  9:59 ` [PATCH 9/9] smb: client: apply rasize on remount rajasimandalos
2026-04-13 13:29   ` Meetakshi Setiya
2026-04-13  7:32 ` [PATCH v2 1/9] smb: client: block non-reconfigurable option changes " Rajasi Mandal
2026-04-17 14:05   ` Meetakshi Setiya

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