+static void ublk_dev_param_basic_apply(struct ublk_device *ub)
+{
+ struct request_queue *q = ub->ub_disk->queue;
+ const struct ublk_param_basic *p = &ub->params.basic;
+
+ blk_queue_logical_block_size(q, 1 << p->logical_bs_shift);
+ blk_queue_physical_block_size(q, 1 << p->physical_bs_shift);
+ blk_queue_io_min(q, 1 << p->io_min_shift);
+ blk_queue_io_opt(q, 1 << p->io_opt_shift);
+
+ blk_queue_write_cache(q, p->attrs & UBLK_ATTR_VOLATILE_CACHE,
+ p->attrs & UBLK_ATTR_FUA);
+ if (p->attrs & UBLK_ATTR_ROTATIONAL)
+ blk_queue_flag_clear(QUEUE_FLAG_NONROT, q);
+ else
+ blk_queue_flag_set(QUEUE_FLAG_NONROT, q);
+
+ blk_queue_max_hw_sectors(q, p->max_sectors);
+ blk_queue_chunk_sectors(q, p->chunk_sectors);
+ blk_queue_virt_boundary(q, p->virt_boundary_mask);
+
+ if (p->attrs & UBLK_ATTR_READ_ONLY)
+ set_disk_ro(ub->ub_disk, true);
+
+ set_capacity(ub->ub_disk, p->dev_sectors);
+}
+
+static void ublk_dev_param_discard_apply(struct ublk_device *ub)
+{
+ struct request_queue *q = ub->ub_disk->queue;
+ const struct ublk_param_discard *p = &ub->params.discard;
+
+ q->limits.discard_alignment = p->discard_alignment;
+ q->limits.discard_granularity = p->discard_granularity;
+ blk_queue_max_discard_sectors(q, p->max_discard_sectors);
+ blk_queue_max_write_zeroes_sectors(q,
+ p->max_write_zeroes_sectors);
+ blk_queue_max_discard_segments(q, p->max_discard_segments);
+}
+
+static int ublk_validate_params(const struct ublk_device *ub)
+{
+ /* basic param is the only one which must be set */
+ if (ub->params.types & UBLK_PARAM_TYPE_BASIC) {
+ const struct ublk_param_basic *p = &ub->params.basic;
+
+ if (p->logical_bs_shift > PAGE_SHIFT)
+ return -EINVAL;
+
+ if (p->logical_bs_shift > p->physical_bs_shift)
+ return -EINVAL;
+
+ if (p->max_sectors > (ub->dev_info.rq_max_blocks <<
+ (ub->bs_shift - 9)))
+ return -EINVAL;
+ } else
+ return -EINVAL;
+
+ if (ub->params.types & UBLK_PARAM_TYPE_DISCARD) {
+ const struct ublk_param_discard *p = &ub->params.discard;
+
+ /* So far, only support single segment discard */
+ if (p->max_discard_sectors && p->max_discard_segments != 1)
+ return -EINVAL;
+
+ if (!p->discard_granularity)
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int ublk_apply_params(struct ublk_device *ub)
+{
+ if (!(ub->params.types & UBLK_PARAM_TYPE_BASIC))
+ return -EINVAL;
+
+ ublk_dev_param_basic_apply(ub);
+
+ if (ub->params.types & UBLK_PARAM_TYPE_DISCARD)
+ ublk_dev_param_discard_apply(ub);
+
+ return 0;
+}
+