Commit b95239ca authored by Jeff Layton's avatar Jeff Layton Committed by Chuck Lever
Browse files

nfsd: make nfsd4_run_cb a bool return function 



queue_work can return false and not queue anything, if the work is
already queued. If that happens in the case of a CB_RECALL, we'll have
taken an extra reference to the stid that will never be put. Ensure we
throw a warning in that case.

Signed-off-by: default avatarJeff Layton <jlayton@kernel.org>
Signed-off-by: default avatarChuck Lever <chuck.lever@oracle.com>
parent 25fbe1fc

fs/nfsd/nfs4callback.c

+12 −2
Original line number Diff line number Diff line
@@ -1371,11 +1371,21 @@ void nfsd4_init_cb(struct nfsd4_callback *cb, struct nfs4_client *clp, 
	cb->cb_holds_slot = false;

}



void nfsd4_run_cb(struct nfsd4_callback *cb)

/**

 * nfsd4_run_cb - queue up a callback job to run

 * @cb: callback to queue

 *

 * Kick off a callback to do its thing. Returns false if it was already

 * on a queue, true otherwise.

 */

bool nfsd4_run_cb(struct nfsd4_callback *cb)

{

	struct nfs4_client *clp = cb->cb_clp;

	bool queued;



	nfsd41_cb_inflight_begin(clp);

	if (!nfsd4_queue_cb(cb))

	queued = nfsd4_queue_cb(cb);

	if (!queued)

		nfsd41_cb_inflight_end(clp);

	return queued;

}

fs/nfsd/nfs4state.c

+2 −3
Original line number Diff line number Diff line
@@ -4859,14 +4859,13 @@ static void nfsd_break_one_deleg(struct nfs4_delegation *dp) 
	 * we know it's safe to take a reference.

	 */

	refcount_inc(&dp->dl_stid.sc_count);

	nfsd4_run_cb(&dp->dl_recall);

	WARN_ON_ONCE(!nfsd4_run_cb(&dp->dl_recall));

}



/* Called from break_lease() with flc_lock held. */

static bool

nfsd_break_deleg_cb(struct file_lock *fl)

{

	bool ret = false;

	struct nfs4_delegation *dp = (struct nfs4_delegation *)fl->fl_owner;

	struct nfs4_file *fp = dp->dl_stid.sc_file;

	struct nfs4_client *clp = dp->dl_stid.sc_client;
@@ -4892,7 +4891,7 @@ nfsd_break_deleg_cb(struct file_lock *fl) 
	fp->fi_had_conflict = true;

	nfsd_break_one_deleg(dp);

	spin_unlock(&fp->fi_lock);

	return ret;

	return false;

}



/**

fs/nfsd/state.h

+1 −1
Original line number Diff line number Diff line
@@ -692,7 +692,7 @@ extern void nfsd4_probe_callback_sync(struct nfs4_client *clp); 
extern void nfsd4_change_callback(struct nfs4_client *clp, struct nfs4_cb_conn *);

extern void nfsd4_init_cb(struct nfsd4_callback *cb, struct nfs4_client *clp,

		const struct nfsd4_callback_ops *ops, enum nfsd4_cb_op op);

extern void nfsd4_run_cb(struct nfsd4_callback *cb);

extern bool nfsd4_run_cb(struct nfsd4_callback *cb);

extern int nfsd4_create_callback_queue(void);

extern void nfsd4_destroy_callback_queue(void);

extern void nfsd4_shutdown_callback(struct nfs4_client *);