diff --git a/drivers/block/nvme-core.c b/drivers/block/nvme-core.c
index fb21d36..c70eff3 100644
--- a/drivers/block/nvme-core.c
+++ b/drivers/block/nvme-core.c
@@ -763,11 +763,13 @@
 	struct nvme_iod *iod;
 	int psegs = bio_phys_segments(ns->queue, bio);
 	int result;
+	unsigned size = !(bio->bi_rw & REQ_DISCARD) ? bio->bi_iter.bi_size :
+						sizeof(struct nvme_dsm_range);
 
 	if ((bio->bi_rw & REQ_FLUSH) && psegs)
 		return nvme_split_flush_data(nvmeq, bio);
 
-	iod = nvme_alloc_iod(psegs, bio->bi_iter.bi_size, ns->dev, GFP_ATOMIC);
+	iod = nvme_alloc_iod(psegs, size, ns->dev, GFP_ATOMIC);
 	if (!iod)
 		return -ENOMEM;