unsigned long write_err;
 
        /*
-        * Either READ or WRITE
+        * REQ_OP_READ, REQ_OP_WRITE or REQ_OP_WRITE_ZEROES.
         */
-       int rw;
+       enum req_op op;
        struct dm_io_region source;
 
        /*
         * constraint and sequential writes that are at the right position.
         */
        list_for_each_entry(job, jobs, list) {
-               if (job->rw == READ || !(job->flags & BIT(DM_KCOPYD_WRITE_SEQ))) {
+               if (job->op == REQ_OP_READ ||
+                   !(job->flags & BIT(DM_KCOPYD_WRITE_SEQ))) {
                        list_del(&job->list);
                        return job;
                }
        io_job_finish(kc->throttle);
 
        if (error) {
-               if (op_is_write(job->rw))
+               if (op_is_write(job->op))
                        job->write_err |= error;
                else
                        job->read_err = 1;
                }
        }
 
-       if (op_is_write(job->rw))
+       if (op_is_write(job->op))
                push(&kc->complete_jobs, job);
 
        else {
-               job->rw = WRITE;
+               job->op = REQ_OP_WRITE;
                push(&kc->io_jobs, job);
        }
 
 {
        int r;
        struct dm_io_request io_req = {
-               .bi_opf = job->rw,
+               .bi_opf = job->op,
                .mem.type = DM_IO_PAGE_LIST,
                .mem.ptr.pl = job->pages,
                .mem.offset = 0,
 
        io_job_start(job->kc->throttle);
 
-       if (job->rw == READ)
+       if (job->op == REQ_OP_READ)
                r = dm_io(&io_req, 1, &job->source, NULL);
        else
                r = dm_io(&io_req, job->num_dests, job->dests, NULL);
 
                if (r < 0) {
                        /* error this rogue job */
-                       if (op_is_write(job->rw))
+                       if (op_is_write(job->op))
                                job->write_err = (unsigned long) -1L;
                        else
                                job->read_err = 1;
        if (from) {
                job->source = *from;
                job->pages = NULL;
-               job->rw = READ;
+               job->op = REQ_OP_READ;
        } else {
                memset(&job->source, 0, sizeof job->source);
                job->source.count = job->dests[0].count;
                /*
                 * Use WRITE ZEROES to optimize zeroing if all dests support it.
                 */
-               job->rw = REQ_OP_WRITE_ZEROES;
+               job->op = REQ_OP_WRITE_ZEROES;
                for (i = 0; i < job->num_dests; i++)
                        if (!bdev_write_zeroes_sectors(job->dests[i].bdev)) {
-                               job->rw = WRITE;
+                               job->op = REQ_OP_WRITE;
                                break;
                        }
        }