FS-Cache: Fix operation handling

fscache_submit_exclusive_op() adds an operation to the pending list if
other operations are pending. Fix the check for pending ops as n_ops
must be greater than 0 at the point it is checked as it is incremented
immediately before under lock.

Signed-off-by: Akshat Aranya <[e-mail]>
Signed-off-by: David Howells <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

fs/fscache/operation.c

···
 		object->n_ops++;
 		object->n_exclusive++;	/* reads and writes must wait */
 
-		if (object->n_ops > 0) {
+		if (object->n_ops > 1) {
 			atomic_inc(&op->usage);
 			list_add_tail(&op->pend_link, &object->pending_ops);
 			fscache_stat(&fscache_n_op_pend);