> - if (sg_res_in_use(sfp)) {
> + mutex_lock(&sfp->f_mutex);
> + if (sfp->res_in_use) {
> + mutex_unlock(&sfp->f_mutex);
> sg_remove_request(sfp, srp);
> return -EBUSY; /* reserve buffer already being used */
> }
> + mutex_unlock(&sfp->f_mutex);
Holding a mutex over a the check of a single scalar doesn't make sense.
