scsi: libsas: Abort all in-flight requests when device is gone

When a disk is removed with in-flight I/O, the application needs to wait
for 30 seconds (depending on the timeout configuration) to hear back from
the kernel. Xingui tried to fix this issue by aborting the ATA link for
SATA devices[1], however this approach left the SAS devices unresolved.

Try to fix this issue by aborting all in-flight requests when the device is
gone. This is implemented by iterating over the tagset.

[1] https://lore.kernel.org/lkml/234e04db-7539-07e4-a6b8-c6b05f78193d@opensource.wdc.com/T/

Cc: Xingui Yang <yangxingui@huawei.com>
Cc: John Garry <john.g.garry@oracle.com>
Cc: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Cc: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Link: https://lore.kernel.org/r/20230330110930.175539-1-yanaijie@huawei.com
Reviewed-by: John Garry <john.g.garry@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 29 insertions, 0 deletions

diff --git a/drivers/scsi/libsas/sas_discover.c b/drivers/scsi/libsas/sas_discover.c
index 72fdb2e5d047..8c6afe724944 100644
--- a/drivers/scsi/libsas/sas_discover.c
+++ b/drivers/scsi/libsas/sas_discover.c
@@ -360,6 +360,33 @@ static void sas_destruct_ports(struct asd_sas_port *port)
 	}
 }
 
+static bool sas_abort_cmd(struct request *req, void *data)
+{
+	struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req);
+	struct domain_device *dev = data;
+
+	if (dev == cmd_to_domain_dev(cmd))
+		blk_abort_request(req);
+	return true;
+}
+
+static void sas_abort_device_scsi_cmds(struct domain_device *dev)
+{
+	struct sas_ha_struct *sas_ha = dev->port->ha;
+	struct Scsi_Host *shost = sas_ha->core.shost;
+
+	if (dev_is_expander(dev->dev_type))
+		return;
+
+	/*
+	 * For removed device with active IOs, the user space applications have
+	 * to spend very long time waiting for the timeout. This is not
+	 * necessary because a removed device will not return the IOs.
+	 * Abort the inflight IOs here so that EH can be quickly kicked in.
+	 */
+	blk_mq_tagset_busy_iter(&shost->tag_set, sas_abort_cmd, dev);
+}
+
 void sas_unregister_dev(struct asd_sas_port *port, struct domain_device *dev)
 {
 	if (!test_bit(SAS_DEV_DESTROY, &dev->state) &&
@@ -372,6 +399,8 @@ void sas_unregister_dev(struct asd_sas_port *port, struct domain_device *dev)
 	}
 
 	if (!test_and_set_bit(SAS_DEV_DESTROY, &dev->state)) {
+		if (test_bit(SAS_DEV_GONE, &dev->state))
+			sas_abort_device_scsi_cmds(dev);
 		sas_rphy_unlink(dev->rphy);
 		list_move_tail(&dev->disco_list_node, &port->destroy_list);
 	}