1 files changed, 20 insertions, 0 deletions

diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 7ff4f252ca1a..f8b906843926 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -778,6 +778,12 @@ static void ops_run_io(struct stripe_head *sh, struct stripe_head_state *s)
                         bi->bi_io_vec[0].bv_len = STRIPE_SIZE;
                         bi->bi_io_vec[0].bv_offset = 0;
                         bi->bi_size = STRIPE_SIZE;
+                        /*
+                         * If this is discard request, set bi_vcnt 0. We don't
+                         * want to confuse SCSI because SCSI will replace payload
+                         */
+                        if (rw & REQ_DISCARD)
+                                bi->bi_vcnt = 0;
                         if (rrdev)
                                 set_bit(R5_DOUBLE_LOCKED, &sh->dev[i].flags);
 
@@ -816,6 +822,12 @@ static void ops_run_io(struct stripe_head *sh, struct stripe_head_state *s)
                         rbi->bi_io_vec[0].bv_len = STRIPE_SIZE;
                         rbi->bi_io_vec[0].bv_offset = 0;
                         rbi->bi_size = STRIPE_SIZE;
+                        /*
+                         * If this is discard request, set bi_vcnt 0. We don't
+                         * want to confuse SCSI because SCSI will replace payload
+                         */
+                        if (rw & REQ_DISCARD)
+                                rbi->bi_vcnt = 0;
                         if (conf->mddev->gendisk)
                                 trace_block_bio_remap(bdev_get_queue(rbi->bi_bdev),
                                                       rbi, disk_devt(conf->mddev->gendisk),
@@ -2910,6 +2922,14 @@ static void handle_stripe_clean_event(struct r5conf *conf,
                 }
                 /* now that discard is done we can proceed with any sync */
                 clear_bit(STRIPE_DISCARD, &sh->state);
+                /*
+                 * SCSI discard will change some bio fields and the stripe has
+                 * no updated data, so remove it from hash list and the stripe
+                 * will be reinitialized
+                 */
+                spin_lock_irq(&conf->device_lock);
+                remove_hash(sh);
+                spin_unlock_irq(&conf->device_lock);
                 if (test_bit(STRIPE_SYNC_REQUESTED, &sh->state))
                         set_bit(STRIPE_HANDLE, &sh->state);