isci: replace isci_timer list with proper embedded timers
Rather than preallocating a list of timers and doling them out at runtime,
embed a struct timerlist in each object that needs one. A struct sci_timer
interface is introduced to manage the timer cancellation semantics which
currently need to guarantee the timer is cancelled while holding
spin_lock(ihost->scic_lock). Since the timeout functions also need to acquire
the lock it currently prevents the driver from using del_timer_sync() for
runtime cancellations.
del_timer_sync() is used however before the objects go out of scope.
Signed-off-by: Edmund Nadolski <edmund.nadolski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/drivers/scsi/isci/host.c b/drivers/scsi/isci/host.c
index 6cd7648..a3269b6 100644
--- a/drivers/scsi/isci/host.c
+++ b/drivers/scsi/isci/host.c
@@ -1359,6 +1359,13 @@
wait_for_stop(ihost);
scic_controller_reset(&ihost->sci);
+
+ /* Cancel any/all outstanding port timers */
+ for (i = 0; i < ihost->sci.logical_port_entries; i++) {
+ struct scic_sds_port *sci_port = &ihost->ports[i].sci;
+ del_timer_sync(&sci_port->timer.timer);
+ }
+
isci_timer_list_destroy(ihost);
}
diff --git a/drivers/scsi/isci/isci.h b/drivers/scsi/isci/isci.h
index 69826ea..2fe5557 100644
--- a/drivers/scsi/isci/isci.h
+++ b/drivers/scsi/isci/isci.h
@@ -551,4 +551,37 @@
irqreturn_t isci_msix_isr(int vec, void *data);
irqreturn_t isci_intx_isr(int vec, void *data);
irqreturn_t isci_error_isr(int vec, void *data);
+
+/*
+ * Each timer is associated with a cancellation flag that is set when
+ * del_timer() is called and checked in the timer callback function. This
+ * is needed since del_timer_sync() cannot be called with scic_lock held.
+ * For deinit however, del_timer_sync() is used without holding the lock.
+ */
+struct sci_timer {
+ struct timer_list timer;
+ bool cancel;
+};
+
+static inline
+void sci_init_timer(struct sci_timer *tmr, void (*fn)(unsigned long))
+{
+ tmr->timer.function = fn;
+ tmr->timer.data = (unsigned long) tmr;
+ tmr->cancel = 0;
+ init_timer(&tmr->timer);
+}
+
+static inline void sci_mod_timer(struct sci_timer *tmr, unsigned long msec)
+{
+ tmr->cancel = 0;
+ mod_timer(&tmr->timer, jiffies + msecs_to_jiffies(msec));
+}
+
+static inline void sci_del_timer(struct sci_timer *tmr)
+{
+ tmr->cancel = 1;
+ del_timer(&tmr->timer);
+}
+
#endif /* __ISCI_H__ */
diff --git a/drivers/scsi/isci/port.c b/drivers/scsi/isci/port.c
index 3050415..3da9048 100644
--- a/drivers/scsi/isci/port.c
+++ b/drivers/scsi/isci/port.c
@@ -926,17 +926,19 @@
return true;
}
-/**
- * This method is provided to timeout requests for port operations. Mostly its
- * for the port reset operation.
- *
- *
- */
-static void scic_sds_port_timeout_handler(void *port)
+static void port_timeout(unsigned long data)
{
- struct scic_sds_port *sci_port = port;
+ struct sci_timer *tmr = (struct sci_timer *)data;
+ struct scic_sds_port *sci_port = container_of(tmr, typeof(*sci_port), timer);
+ struct isci_host *ihost = scic_to_ihost(sci_port->owning_controller);
+ unsigned long flags;
u32 current_state;
+ spin_lock_irqsave(&ihost->scic_lock, flags);
+
+ if (tmr->cancel)
+ goto done;
+
current_state = sci_base_state_machine_get_state(&sci_port->state_machine);
if (current_state == SCI_BASE_PORT_STATE_RESETTING) {
@@ -965,6 +967,9 @@
"%s: SCIC Port 0x%p is processing a timeout operation "
"in state %d.\n", __func__, sci_port, current_state);
}
+
+done:
+ spin_unlock_irqrestore(&ihost->scic_lock, flags);
}
/* --------------------------------------------------------------------------- */
@@ -1259,7 +1264,6 @@
enum sci_status scic_sds_port_start(struct scic_sds_port *sci_port)
{
struct scic_sds_controller *scic = sci_port->owning_controller;
- struct isci_host *ihost = scic_to_ihost(scic);
enum sci_status status = SCI_SUCCESS;
enum scic_sds_port_states state;
u32 phy_mask;
@@ -1280,14 +1284,6 @@
return SCI_FAILURE_UNSUPPORTED_PORT_CONFIGURATION;
}
- sci_port->timer_handle =
- isci_timer_create(ihost,
- sci_port,
- scic_sds_port_timeout_handler);
-
- if (!sci_port->timer_handle)
- return SCI_FAILURE_INSUFFICIENT_RESOURCES;
-
if (sci_port->reserved_rni == SCU_DUMMY_INDEX) {
u16 rni = scic_sds_remote_node_table_allocate_remote_node(
&scic->available_remote_nodes, 1);
@@ -1390,7 +1386,7 @@
if (status != SCI_SUCCESS)
return status;
- isci_timer_start(sci_port->timer_handle, timeout);
+ sci_mod_timer(&sci_port->timer, timeout);
sci_port->not_ready_reason = SCIC_PORT_NOT_READY_HARD_RESET_REQUESTED;
port_state_machine_change(sci_port,
@@ -1757,14 +1753,14 @@
{
struct scic_sds_port *sci_port = container_of(sm, typeof(*sci_port), state_machine);
- isci_timer_stop(sci_port->timer_handle);
+ sci_del_timer(&sci_port->timer);
}
static void scic_sds_port_stopping_state_exit(struct sci_base_state_machine *sm)
{
struct scic_sds_port *sci_port = container_of(sm, typeof(*sci_port), state_machine);
- isci_timer_stop(sci_port->timer_handle);
+ sci_del_timer(&sci_port->timer);
scic_sds_port_destroy_dummy_resources(sci_port);
}
@@ -1831,7 +1827,8 @@
sci_port->reserved_rni = SCU_DUMMY_INDEX;
sci_port->reserved_tci = SCU_DUMMY_INDEX;
- sci_port->timer_handle = NULL;
+ sci_init_timer(&sci_port->timer, port_timeout);
+
sci_port->port_task_scheduler_registers = NULL;
for (index = 0; index < SCI_MAX_PHYS; index++)
diff --git a/drivers/scsi/isci/port.h b/drivers/scsi/isci/port.h
index af540e5..9a69128 100644
--- a/drivers/scsi/isci/port.h
+++ b/drivers/scsi/isci/port.h
@@ -139,10 +139,8 @@
*/
struct scic_sds_controller *owning_controller;
- /**
- * This field contains the port start/stop timer handle.
- */
- void *timer_handle;
+ /* timer used for port start/stop operations */
+ struct sci_timer timer;
/**
* This field is the pointer to the port task scheduler registers