1 files changed, 11 insertions, 4 deletions

diff --git a/drivers/md/dm-io.c b/drivers/md/dm-io.c
index 37de0173b6d2..74adcd2c967e 100644
--- a/drivers/md/dm-io.c
+++ b/drivers/md/dm-io.c
@@ -289,9 +289,16 @@ static void do_region(int rw, unsigned region, struct dm_io_region *where,
         struct request_queue *q = bdev_get_queue(where->bdev);
         unsigned short logical_block_size = queue_logical_block_size(q);
         sector_t num_sectors;
+        unsigned int uninitialized_var(special_cmd_max_sectors);
 
-        /* Reject unsupported discard requests */
-        if ((rw & REQ_DISCARD) && !blk_queue_discard(q)) {
+        /*
+         * Reject unsupported discard and write same requests.
+         */
+        if (rw & REQ_DISCARD)
+                special_cmd_max_sectors = q->limits.max_discard_sectors;
+        else if (rw & REQ_WRITE_SAME)
+                special_cmd_max_sectors = q->limits.max_write_same_sectors;
+        if ((rw & (REQ_DISCARD | REQ_WRITE_SAME)) && special_cmd_max_sectors == 0) {
                 dec_count(io, region, -EOPNOTSUPP);
                 return;
         }
@@ -317,7 +324,7 @@ static void do_region(int rw, unsigned region, struct dm_io_region *where,
                 store_io_and_region_in_bio(bio, io, region);
 
                 if (rw & REQ_DISCARD) {
-                        num_sectors = min_t(sector_t, q->limits.max_discard_sectors, remaining);
+                        num_sectors = min_t(sector_t, special_cmd_max_sectors, remaining);
                         bio->bi_iter.bi_size = num_sectors << SECTOR_SHIFT;
                         remaining -= num_sectors;
                 } else if (rw & REQ_WRITE_SAME) {
@@ -326,7 +333,7 @@ static void do_region(int rw, unsigned region, struct dm_io_region *where,
                          */
                         dp->get_page(dp, &page, &len, &offset);
                         bio_add_page(bio, page, logical_block_size, offset);
-                        num_sectors = min_t(sector_t, q->limits.max_write_same_sectors, remaining);
+                        num_sectors = min_t(sector_t, special_cmd_max_sectors, remaining);
                         bio->bi_iter.bi_size = num_sectors << SECTOR_SHIFT;
 
                         offset = 0;