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path: root/drivers/scsi/scsi_transport_srp.c
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Diffstat (limited to 'drivers/scsi/scsi_transport_srp.c')
-rw-r--r--drivers/scsi/scsi_transport_srp.c95
1 files changed, 57 insertions, 38 deletions
diff --git a/drivers/scsi/scsi_transport_srp.c b/drivers/scsi/scsi_transport_srp.c
index 2700a5a09bd4..d47ffc8d3e43 100644
--- a/drivers/scsi/scsi_transport_srp.c
+++ b/drivers/scsi/scsi_transport_srp.c
@@ -64,10 +64,14 @@ static inline struct Scsi_Host *rport_to_shost(struct srp_rport *r)
/**
* srp_tmo_valid() - check timeout combination validity
+ * @reconnect_delay: Reconnect delay in seconds.
+ * @fast_io_fail_tmo: Fast I/O fail timeout in seconds.
+ * @dev_loss_tmo: Device loss timeout in seconds.
*
* The combination of the timeout parameters must be such that SCSI commands
* are finished in a reasonable time. Hence do not allow the fast I/O fail
- * timeout to exceed SCSI_DEVICE_BLOCK_MAX_TIMEOUT. Furthermore, these
+ * timeout to exceed SCSI_DEVICE_BLOCK_MAX_TIMEOUT nor allow dev_loss_tmo to
+ * exceed that limit if failing I/O fast has been disabled. Furthermore, these
* parameters must be such that multipath can detect failed paths timely.
* Hence do not allow all three parameters to be disabled simultaneously.
*/
@@ -79,6 +83,9 @@ int srp_tmo_valid(int reconnect_delay, int fast_io_fail_tmo, int dev_loss_tmo)
return -EINVAL;
if (fast_io_fail_tmo > SCSI_DEVICE_BLOCK_MAX_TIMEOUT)
return -EINVAL;
+ if (fast_io_fail_tmo < 0 &&
+ dev_loss_tmo > SCSI_DEVICE_BLOCK_MAX_TIMEOUT)
+ return -EINVAL;
if (dev_loss_tmo >= LONG_MAX / HZ)
return -EINVAL;
if (fast_io_fail_tmo >= 0 && dev_loss_tmo >= 0 &&
@@ -368,6 +375,7 @@ invalid:
/**
* srp_reconnect_work() - reconnect and schedule a new attempt if necessary
+ * @work: Work structure used for scheduling this operation.
*/
static void srp_reconnect_work(struct work_struct *work)
{
@@ -408,6 +416,7 @@ static void __rport_fail_io_fast(struct srp_rport *rport)
/**
* rport_fast_io_fail_timedout() - fast I/O failure timeout handler
+ * @work: Work structure used for scheduling this operation.
*/
static void rport_fast_io_fail_timedout(struct work_struct *work)
{
@@ -426,6 +435,7 @@ static void rport_fast_io_fail_timedout(struct work_struct *work)
/**
* rport_dev_loss_timedout() - device loss timeout handler
+ * @work: Work structure used for scheduling this operation.
*/
static void rport_dev_loss_timedout(struct work_struct *work)
{
@@ -452,42 +462,35 @@ static void __srp_start_tl_fail_timers(struct srp_rport *rport)
lockdep_assert_held(&rport->mutex);
- if (!rport->deleted) {
- delay = rport->reconnect_delay;
- fast_io_fail_tmo = rport->fast_io_fail_tmo;
- dev_loss_tmo = rport->dev_loss_tmo;
- pr_debug("%s current state: %d\n",
- dev_name(&shost->shost_gendev), rport->state);
+ delay = rport->reconnect_delay;
+ fast_io_fail_tmo = rport->fast_io_fail_tmo;
+ dev_loss_tmo = rport->dev_loss_tmo;
+ pr_debug("%s current state: %d\n", dev_name(&shost->shost_gendev),
+ rport->state);
- if (delay > 0)
- queue_delayed_work(system_long_wq,
- &rport->reconnect_work,
- 1UL * delay * HZ);
- if (fast_io_fail_tmo >= 0 &&
- 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);
+ if (rport->state == SRP_RPORT_LOST)
+ return;
+ if (delay > 0)
+ queue_delayed_work(system_long_wq, &rport->reconnect_work,
+ 1UL * delay * HZ);
+ if (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);
+ if (fast_io_fail_tmo >= 0)
queue_delayed_work(system_long_wq,
&rport->fast_io_fail_work,
1UL * fast_io_fail_tmo * HZ);
- }
if (dev_loss_tmo >= 0)
queue_delayed_work(system_long_wq,
&rport->dev_loss_work,
1UL * dev_loss_tmo * HZ);
- } else {
- pr_debug("%s has already been deleted\n",
- dev_name(&shost->shost_gendev));
- srp_rport_set_state(rport, SRP_RPORT_FAIL_FAST);
- scsi_target_unblock(&shost->shost_gendev,
- SDEV_TRANSPORT_OFFLINE);
}
}
/**
* srp_start_tl_fail_timers() - start the transport layer failure timers
+ * @rport: SRP target port.
*
* Start the transport layer fast I/O failure and device loss timers. Do not
* modify a timer that was already started.
@@ -502,6 +505,7 @@ EXPORT_SYMBOL(srp_start_tl_fail_timers);
/**
* scsi_request_fn_active() - number of kernel threads inside scsi_request_fn()
+ * @shost: SCSI host for which to count the number of scsi_request_fn() callers.
*/
static int scsi_request_fn_active(struct Scsi_Host *shost)
{
@@ -522,6 +526,7 @@ static int scsi_request_fn_active(struct Scsi_Host *shost)
/**
* srp_reconnect_rport() - reconnect to an SRP target port
+ * @rport: SRP target port.
*
* Blocks SCSI command queueing before invoking reconnect() such that
* queuecommand() won't be invoked concurrently with reconnect() from outside
@@ -556,7 +561,7 @@ int srp_reconnect_rport(struct srp_rport *rport)
scsi_target_block(&shost->shost_gendev);
while (scsi_request_fn_active(shost))
msleep(20);
- res = i->f->reconnect(rport);
+ 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);
if (res == 0) {
@@ -578,9 +583,9 @@ int srp_reconnect_rport(struct srp_rport *rport)
spin_unlock_irq(shost->host_lock);
} else if (rport->state == SRP_RPORT_RUNNING) {
/*
- * srp_reconnect_rport() was invoked with fast_io_fail
- * off. Mark the port as failed and start the TL failure
- * timers if these had not yet been started.
+ * srp_reconnect_rport() has been invoked with fast_io_fail
+ * and dev_loss off. Mark the port as failed and start the TL
+ * failure timers if these had not yet been started.
*/
__rport_fail_io_fast(rport);
scsi_target_unblock(&shost->shost_gendev,
@@ -599,6 +604,7 @@ EXPORT_SYMBOL(srp_reconnect_rport);
/**
* srp_timed_out() - SRP transport intercept of the SCSI timeout EH
+ * @scmd: SCSI command.
*
* If a timeout occurs while an rport is in the blocked state, ask the SCSI
* EH to continue waiting (BLK_EH_RESET_TIMER). Otherwise let the SCSI core
@@ -622,10 +628,6 @@ static void srp_rport_release(struct device *dev)
{
struct srp_rport *rport = dev_to_rport(dev);
- cancel_delayed_work_sync(&rport->reconnect_work);
- cancel_delayed_work_sync(&rport->fast_io_fail_work);
- cancel_delayed_work_sync(&rport->dev_loss_work);
-
put_device(dev->parent);
kfree(rport);
}
@@ -674,6 +676,7 @@ static int srp_host_match(struct attribute_container *cont, struct device *dev)
/**
* srp_rport_get() - increment rport reference count
+ * @rport: SRP target port.
*/
void srp_rport_get(struct srp_rport *rport)
{
@@ -683,6 +686,7 @@ EXPORT_SYMBOL(srp_rport_get);
/**
* srp_rport_put() - decrement rport reference count
+ * @rport: SRP target port.
*/
void srp_rport_put(struct srp_rport *rport)
{
@@ -780,12 +784,6 @@ void srp_rport_del(struct srp_rport *rport)
device_del(dev);
transport_destroy_device(dev);
- mutex_lock(&rport->mutex);
- if (rport->state == SRP_RPORT_BLOCKED)
- __rport_fail_io_fast(rport);
- rport->deleted = true;
- mutex_unlock(&rport->mutex);
-
put_device(dev);
}
EXPORT_SYMBOL_GPL(srp_rport_del);
@@ -810,6 +808,27 @@ void srp_remove_host(struct Scsi_Host *shost)
}
EXPORT_SYMBOL_GPL(srp_remove_host);
+/**
+ * srp_stop_rport_timers - stop the transport layer recovery timers
+ *
+ * Must be called after srp_remove_host() and scsi_remove_host(). The caller
+ * must hold a reference on the rport (rport->dev) and on the SCSI host
+ * (rport->dev.parent).
+ */
+void srp_stop_rport_timers(struct srp_rport *rport)
+{
+ mutex_lock(&rport->mutex);
+ if (rport->state == SRP_RPORT_BLOCKED)
+ __rport_fail_io_fast(rport);
+ srp_rport_set_state(rport, SRP_RPORT_LOST);
+ mutex_unlock(&rport->mutex);
+
+ cancel_delayed_work_sync(&rport->reconnect_work);
+ cancel_delayed_work_sync(&rport->fast_io_fail_work);
+ cancel_delayed_work_sync(&rport->dev_loss_work);
+}
+EXPORT_SYMBOL_GPL(srp_stop_rport_timers);
+
static int srp_tsk_mgmt_response(struct Scsi_Host *shost, u64 nexus, u64 tm_id,
int result)
{