Re: [PATCH 10/13] nfsd: allow lock state ids to be revoked and then freed

[Jeff Layton <jlayton@kernel.org>]

On Mon, 2024-01-29 at 14:29 +1100, NeilBrown wrote:
> Revoking state through 'unlock_filesystem' now revokes any lock states
> found.  When the stateids are then freed by the client, the revoked
> stateids will be cleaned up correctly.
> 
> Signed-off-by: NeilBrown <neilb@suse.de>
> ---
>  fs/nfsd/nfs4state.c | 40 +++++++++++++++++++++++++++++++++++++++-
>  1 file changed, 39 insertions(+), 1 deletion(-)
> 
> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
> index 900d295bd570..a5c17dab8bdb 100644
> --- a/fs/nfsd/nfs4state.c
> +++ b/fs/nfsd/nfs4state.c
> @@ -1717,7 +1717,7 @@ void nfsd4_revoke_states(struct net *net, struct super_block *sb)
>  	unsigned int idhashval;
>  	unsigned int sc_types;
>  
> -	sc_types = 0;
> +	sc_types = SC_TYPE_LOCK;
>  
>  	spin_lock(&nn->client_lock);
>  	for (idhashval = 0; idhashval < CLIENT_HASH_MASK; idhashval++) {
> @@ -1728,8 +1728,36 @@ void nfsd4_revoke_states(struct net *net, struct super_block *sb)
>  			struct nfs4_stid *stid = find_one_sb_stid(clp, sb,
>  								  sc_types);
>  			if (stid) {
> +				struct nfs4_ol_stateid *stp;
> +
>  				spin_unlock(&nn->client_lock);
>  				switch (stid->sc_type) {
> +				case SC_TYPE_LOCK:
> +					stp = openlockstateid(stid);
> +					mutex_lock_nested(&stp->st_mutex,
> +							  LOCK_STATEID_MUTEX);
> +					spin_lock(&clp->cl_lock);
> +					if (stid->sc_status == 0) {
> +						struct nfs4_lockowner *lo =
> +							lockowner(stp->st_stateowner);
> +						struct nfsd_file *nf;
> +
> +						stid->sc_status |=
> +							SC_STATUS_ADMIN_REVOKED;
> +						atomic_inc(&clp->cl_admin_revoked);
> +						spin_unlock(&clp->cl_lock);
> +						nf = find_any_file(stp->st_stid.sc_file);
> +						if (nf) {
> +							get_file(nf->nf_file);
> +							filp_close(nf->nf_file,
> +								   (fl_owner_t)lo);
> +							nfsd_file_put(nf);
> +						}
> +						release_all_access(stp);
> +					} else
> +						spin_unlock(&clp->cl_lock);
> +					mutex_unlock(&stp->st_mutex);
> +					break;
>  				}
>  				nfs4_put_stid(stid);
>  				spin_lock(&nn->client_lock);
> @@ -4629,8 +4657,18 @@ static void nfsd4_drop_revoked_stid(struct nfs4_stid *s)
>  	__releases(&s->sc_client->cl_lock)
>  {
>  	struct nfs4_client *cl = s->sc_client;
> +	LIST_HEAD(reaplist);
> +	struct nfs4_ol_stateid *stp;
> +	bool unhashed;
>  
>  	switch (s->sc_type) {
> +	case SC_TYPE_LOCK:
> +		stp = openlockstateid(s);
> +		unhashed = unhash_lock_stateid(stp);
> +		spin_unlock(&cl->cl_lock);
> +		if (unhashed)
> +			nfs4_put_stid(s);
> +		break;
>  	default:
>  		spin_unlock(&cl->cl_lock);
>  	}

Reviewed-by: Jeff Layton <jlayton@kernel.org>