[PATCH v5 6/7] scsi: replace scsi_target_block() by scsi_block_targets()

mwilck
2023-06-12T16:52:07Z

From: Martin Wilck <mwilck@suse.com>

All callers (fc_remote_port_delete(), __iscsi_block_session(),
__srp_start_tl_fail_timers(), srp_reconnect_rport(), snic_tgt_del()) pass
parent devices of scsi_target devices to scsi_target_block().

Rename the function to scsi_block_targets(), and simplify it by assuming
that it is always passed a parent device. Also, have callers pass the
Scsi_Host pointer to scsi_block_targets(), as every caller has this pointer
readily available.

Suggested-by: Christoph Hellwig <hch@lst.de>
Suggested-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin Wilck <mwilck@suse.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Cc: Karan Tilak Kumar <kartilak@cisco.com>
Cc: Sesidhar Baddela <sebaddel@cisco.com>
---
drivers/scsi/scsi_lib.c | 26 ++++++++++++++++----------
drivers/scsi/scsi_transport_fc.c | 2 +-
drivers/scsi/scsi_transport_iscsi.c | 3 ++-
drivers/scsi/scsi_transport_srp.c | 6 +++---
drivers/scsi/snic/snic_disc.c | 2 +-
include/scsi/scsi_device.h | 2 +-
6 files changed, 24 insertions(+), 17 deletions(-)

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index f94677b3f5b6..1ddd75e6d600 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -2895,20 +2895,26 @@ target_block(struct device *dev, void *data)
return 0;
}

+/**
+ * scsi_block_targets - transition all SCSI child devices to SDEV_BLOCK state
+ * @dev: a parent device of one or more scsi_target devices
+ * @shost: the Scsi_Host to which this device belongs
+ *
+ * Iterate over all children of @dev, which should be scsi_target devices,
+ * and switch all subordinate scsi devices to SDEV_BLOCK state. Wait for
+ * ongoing scsi_queue_rq() calls to finish. May sleep.
+ *
+ * Note:
+ * @dev must not itself be a scsi_target device.
+ */
void
-scsi_target_block(struct device *dev)
+scsi_block_targets(struct device *dev, struct Scsi_Host *shost)
{
- struct Scsi_Host *shost = dev_to_shost(dev);
-
- if (scsi_is_target_device(dev))
- starget_for_each_device(to_scsi_target(dev), NULL,
- scsi_device_block);
- else
- device_for_each_child(dev, NULL, target_block);
-
+ WARN_ON_ONCE(scsi_is_target_device(dev));
+ device_for_each_child(dev, NULL, target_block);
blk_mq_wait_quiesce_done(&shost->tag_set);
}
-EXPORT_SYMBOL_GPL(scsi_target_block);
+EXPORT_SYMBOL_GPL(scsi_block_targets);

static void
device_unblock(struct scsi_device *sdev, void *data)
diff --git a/drivers/scsi/scsi_transport_fc.c b/drivers/scsi/scsi_transport_fc.c
index 64ff2629eaf9..7fd90b51a7e6 100644
--- a/drivers/scsi/scsi_transport_fc.c
+++ b/drivers/scsi/scsi_transport_fc.c
@@ -3451,7 +3451,7 @@ fc_remote_port_delete(struct fc_rport *rport)

spin_unlock_irqrestore(shost->host_lock, flags);

- scsi_target_block(&rport->dev);
+ scsi_block_targets(&rport->dev, shost);

/* see if we need to kill io faster than waiting for device loss */
if ((rport->fast_io_fail_tmo != -1) &&
diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c
index b9b97300e3b3..0a64ea20f71c 100644
--- a/drivers/scsi/scsi_transport_iscsi.c
+++ b/drivers/scsi/scsi_transport_iscsi.c
@@ -1943,13 +1943,14 @@ static void __iscsi_block_session(struct work_struct *work)
struct iscsi_cls_session *session =
container_of(work, struct iscsi_cls_session,
block_work);
+ struct Scsi_Host *shost = iscsi_session_to_shost(session);
unsigned long flags;

ISCSI_DBG_TRANS_SESSION(session, "Blocking session\n");
spin_lock_irqsave(&session->lock, flags);
session->state = ISCSI_SESSION_FAILED;
spin_unlock_irqrestore(&session->lock, flags);
- scsi_target_block(&session->dev);
+ scsi_block_targets(&session->dev, shost);
ISCSI_DBG_TRANS_SESSION(session, "Completed SCSI target blocking\n");
if (session->recovery_tmo >= 0)
queue_delayed_work(session->workq,
diff --git a/drivers/scsi/scsi_transport_srp.c b/drivers/scsi/scsi_transport_srp.c
index 87d0fb8dc503..787b1a487e51 100644
--- a/drivers/scsi/scsi_transport_srp.c
+++ b/drivers/scsi/scsi_transport_srp.c
@@ -396,7 +396,7 @@ static void srp_reconnect_work(struct work_struct *work)
}

/*
- * scsi_target_block() must have been called before this function is
+ * scsi_block_targets() must have been called before this function is
* called to guarantee that no .queuecommand() calls are in progress.
*/
static void __rport_fail_io_fast(struct srp_rport *rport)
@@ -480,7 +480,7 @@ static void __srp_start_tl_fail_timers(struct srp_rport *rport)
srp_rport_set_state(rport, SRP_RPORT_BLOCKED) == 0) {
pr_debug("%s new state: %d\n", dev_name(&shost->shost_gendev),
rport->state);
- scsi_target_block(&shost->shost_gendev);
+ scsi_block_targets(&shost->shost_gendev, shost);
if (fast_io_fail_tmo >= 0)
queue_delayed_work(system_long_wq,
&rport->fast_io_fail_work,
@@ -548,7 +548,7 @@ int srp_reconnect_rport(struct srp_rport *rport)
* later is ok though, scsi_internal_device_unblock_nowait()
* treats SDEV_TRANSPORT_OFFLINE like SDEV_BLOCK.
*/
- scsi_target_block(&shost->shost_gendev);
+ scsi_block_targets(&shost->shost_gendev, shost);
res = rport->state != SRP_RPORT_LOST ? i->f->reconnect(rport) : -ENODEV;
pr_debug("%s (state %d): transport.reconnect() returned %d\n",
dev_name(&shost->shost_gendev), rport->state, res);
diff --git a/drivers/scsi/snic/snic_disc.c b/drivers/scsi/snic/snic_disc.c
index 8fbf3c1b1311..f81abeccc386 100644
--- a/drivers/scsi/snic/snic_disc.c
+++ b/drivers/scsi/snic/snic_disc.c
@@ -214,7 +214,7 @@ snic_tgt_del(struct work_struct *work)
scsi_flush_work(shost);

/* Block IOs on child devices, stops new IOs */
- scsi_target_block(&tgt->dev);
+ scsi_block_targets(&tgt->dev, shost);

/* Cleanup IOs */
snic_tgt_scsi_abort_io(tgt);
diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h
index b2cdb078b7bd..b31ec356e8f5 100644
--- a/include/scsi/scsi_device.h
+++ b/include/scsi/scsi_device.h
@@ -456,7 +456,7 @@ extern void scsi_scan_target(struct device *parent, unsigned int channel,
unsigned int id, u64 lun,
enum scsi_scan_mode rescan);
extern void scsi_target_reap(struct scsi_target *);
-extern void scsi_target_block(struct device *);
+extern void scsi_block_targets(struct device *dev, struct Scsi_Host *shost);
extern void scsi_target_unblock(struct device *, enum scsi_device_state);
extern void scsi_remove_target(struct device *);
extern const char *scsi_device_state_name(enum scsi_device_state);
--
2.40.1