diff options
| -rw-r--r-- | drivers/scsi/scsi_lib.c | 18 |
1 files changed, 17 insertions, 1 deletions
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index 47835c4b4ee0..ff0449fbe3a0 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -2841,11 +2841,27 @@ scsi_host_block(struct Scsi_Host *shost) struct scsi_device *sdev; int ret = 0; + /* + * Call scsi_internal_device_block_nowait so we can avoid + * calling synchronize_rcu() for each LUN. + */ shost_for_each_device(sdev, shost) { - ret = scsi_internal_device_block(sdev); + mutex_lock(&sdev->state_mutex); + ret = scsi_internal_device_block_nowait(sdev); + mutex_unlock(&sdev->state_mutex); if (ret) break; } + + /* + * SCSI never enables blk-mq's BLK_MQ_F_BLOCKING flag so + * calling synchronize_rcu() once is enough. + */ + WARN_ON_ONCE(shost->tag_set.flags & BLK_MQ_F_BLOCKING); + + if (!ret) + synchronize_rcu(); + return ret; } EXPORT_SYMBOL_GPL(scsi_host_block); |