diff --git a/drivers/md/dm-writecache.c b/drivers/md/dm-writecache.c
index cc028353f9d5594a7cf0766407671be8e561efb1..776aaf5951e4afc9f7d0d721ef1b109c7525bae7 100644
--- a/drivers/md/dm-writecache.c
+++ b/drivers/md/dm-writecache.c
@@ -226,6 +226,7 @@ static int persistent_memory_claim(struct dm_writecache *wc)
 	pfn_t pfn;
 	int id;
 	struct page **pages;
+	sector_t offset;
 
 	wc->memory_vmapped = false;
 
@@ -244,9 +245,16 @@ static int persistent_memory_claim(struct dm_writecache *wc)
 		goto err1;
 	}
 
+	offset = get_start_sect(wc->ssd_dev->bdev);
+	if (offset & (PAGE_SIZE / 512 - 1)) {
+		r = -EINVAL;
+		goto err1;
+	}
+	offset >>= PAGE_SHIFT - 9;
+
 	id = dax_read_lock();
 
-	da = dax_direct_access(wc->ssd_dev->dax_dev, 0, p, &wc->memory_map, &pfn);
+	da = dax_direct_access(wc->ssd_dev->dax_dev, offset, p, &wc->memory_map, &pfn);
 	if (da < 0) {
 		wc->memory_map = NULL;
 		r = da;
@@ -268,7 +276,7 @@ static int persistent_memory_claim(struct dm_writecache *wc)
 		i = 0;
 		do {
 			long daa;
-			daa = dax_direct_access(wc->ssd_dev->dax_dev, i, p - i,
+			daa = dax_direct_access(wc->ssd_dev->dax_dev, offset + i, p - i,
 						NULL, &pfn);
 			if (daa <= 0) {
 				r = daa ? daa : -EINVAL;