[SCSI] gdth: fix timer handling
The global timer handling is problematic in that if someone unbinds a
PCI gdth instance, the BUG_ON() in the timer will cause a panic.
Fix this by making the timer start and stop depending on whether there
are instances present. This should also permit binding and unbinding
to work.
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
diff --git a/drivers/scsi/gdth.c b/drivers/scsi/gdth.c
index 8e2e964..16785a2 100644
--- a/drivers/scsi/gdth.c
+++ b/drivers/scsi/gdth.c
@@ -3724,6 +3724,8 @@
}
#ifdef GDTH_STATISTICS
+static unchar gdth_timer_running;
+
static void gdth_timeout(ulong data)
{
ulong32 i;
@@ -3731,7 +3733,10 @@
gdth_ha_str *ha;
ulong flags;
- BUG_ON(list_empty(&gdth_instances));
+ if(unlikely(list_empty(&gdth_instances))) {
+ gdth_timer_running = 0;
+ return;
+ }
ha = list_first_entry(&gdth_instances, gdth_ha_str, list);
spin_lock_irqsave(&ha->smp_lock, flags);
@@ -3751,6 +3756,22 @@
add_timer(&gdth_timer);
spin_unlock_irqrestore(&ha->smp_lock, flags);
}
+
+static void gdth_timer_init(void)
+{
+ if (gdth_timer_running)
+ return;
+ gdth_timer_running = 1;
+ TRACE2(("gdth_detect(): Initializing timer !\n"));
+ gdth_timer.expires = jiffies + HZ;
+ gdth_timer.data = 0L;
+ gdth_timer.function = gdth_timeout;
+ add_timer(&gdth_timer);
+}
+#else
+static inline void gdth_timer_init(void)
+{
+}
#endif
static void __init internal_setup(char *str,int *ints)
@@ -4735,6 +4756,7 @@
if (error)
goto out_free_coal_stat;
list_add_tail(&ha->list, &gdth_instances);
+ gdth_timer_init();
scsi_scan_host(shp);
@@ -4865,6 +4887,7 @@
if (error)
goto out_free_coal_stat;
list_add_tail(&ha->list, &gdth_instances);
+ gdth_timer_init();
scsi_scan_host(shp);
@@ -5011,6 +5034,7 @@
list_add_tail(&ha->list, &gdth_instances);
pci_set_drvdata(ha->pdev, ha);
+ gdth_timer_init();
scsi_scan_host(shp);
@@ -5110,6 +5134,7 @@
/* initializations */
gdth_polling = TRUE;
gdth_clear_events();
+ init_timer(&gdth_timer);
/* As default we do not probe for EISA or ISA controllers */
if (probe_eisa_isa) {
@@ -5138,17 +5163,6 @@
TRACE2(("gdth_detect() %d controller detected\n", gdth_ctr_count));
- if (list_empty(&gdth_instances))
- return -ENODEV;
-
-#ifdef GDTH_STATISTICS
- TRACE2(("gdth_detect(): Initializing timer !\n"));
- init_timer(&gdth_timer);
- gdth_timer.expires = jiffies + HZ;
- gdth_timer.data = 0L;
- gdth_timer.function = gdth_timeout;
- add_timer(&gdth_timer);
-#endif
major = register_chrdev(0,"gdth", &gdth_fops);
register_reboot_notifier(&gdth_notifier);
gdth_polling = FALSE;