1 files changed, 32 insertions, 1 deletions

diff --git a/drivers/scsi/libsas/sas_init.c b/drivers/scsi/libsas/sas_init.c
index e04f6d6f5aff..22bfc025ae81 100644
--- a/drivers/scsi/libsas/sas_init.c
+++ b/drivers/scsi/libsas/sas_init.c
@@ -123,6 +123,8 @@ int sas_register_ha(struct sas_ha_struct *sas_ha)
         INIT_LIST_HEAD(&sas_ha->defer_q);
         INIT_LIST_HEAD(&sas_ha->eh_dev_q);
 
+        sas_ha->event_thres = SAS_PHY_SHUTDOWN_THRES;
+
         error = sas_register_phys(sas_ha);
         if (error) {
                 printk(KERN_NOTICE "couldn't register sas phys:%d\n", error);
@@ -557,14 +559,43 @@ EXPORT_SYMBOL_GPL(sas_domain_attach_transport);
 
 struct asd_sas_event *sas_alloc_event(struct asd_sas_phy *phy)
 {
+        struct asd_sas_event *event;
         gfp_t flags = in_interrupt() ? GFP_ATOMIC : GFP_KERNEL;
+        struct sas_ha_struct *sas_ha = phy->ha;
+        struct sas_internal *i =
+                to_sas_internal(sas_ha->core.shost->transportt);
+
+        event = kmem_cache_zalloc(sas_event_cache, flags);
+        if (!event)
+                return NULL;
 
-        return kmem_cache_zalloc(sas_event_cache, flags);
+        atomic_inc(&phy->event_nr);
+
+        if (atomic_read(&phy->event_nr) > phy->ha->event_thres) {
+                if (i->dft->lldd_control_phy) {
+                        if (cmpxchg(&phy->in_shutdown, 0, 1) == 0) {
+                                sas_printk("The phy%02d bursting events, shut it down.\n",
+                                        phy->id);
+                                sas_notify_phy_event(phy, PHYE_SHUTDOWN);
+                        }
+                } else {
+                        /* Do not support PHY control, stop allocating events */
+                        WARN_ONCE(1, "PHY control not supported.\n");
+                        kmem_cache_free(sas_event_cache, event);
+                        atomic_dec(&phy->event_nr);
+                        event = NULL;
+                }
+        }
+
+        return event;
 }
 
 void sas_free_event(struct asd_sas_event *event)
 {
+        struct asd_sas_phy *phy = event->phy;
+
         kmem_cache_free(sas_event_cache, event);
+        atomic_dec(&phy->event_nr);
 }
 
 /* ---------- SAS Class register/unregister ---------- */