+/**
+ * fc_fcp_can_queue_ramp_up() - increases can_queue
+ * @lport: lport to ramp up can_queue
+ *
+ * Locking notes: Called with Scsi_Host lock held
+ */
+static void fc_fcp_can_queue_ramp_up(struct fc_lport *lport)
+{
+ struct fc_fcp_internal *si = fc_get_scsi_internal(lport);
+ int can_queue;
+
+ if (si->last_can_queue_ramp_up_time &&
+ (time_before(jiffies, si->last_can_queue_ramp_up_time +
+ FC_CAN_QUEUE_PERIOD)))
+ return;
+
+ if (time_before(jiffies, si->last_can_queue_ramp_down_time +
+ FC_CAN_QUEUE_PERIOD))
+ return;
+
+ si->last_can_queue_ramp_up_time = jiffies;
+
+ can_queue = lport->host->can_queue << 1;
+ if (can_queue >= si->max_can_queue) {
+ can_queue = si->max_can_queue;
+ si->last_can_queue_ramp_down_time = 0;
+ }
+ lport->host->can_queue = can_queue;
+ shost_printk(KERN_ERR, lport->host, "libfc: increased "
+ "can_queue to %d.\n", can_queue);
+}
+
+/**
+ * fc_fcp_can_queue_ramp_down() - reduces can_queue
+ * @lport: lport to reduce can_queue
+ *
+ * If we are getting memory allocation failures, then we may
+ * be trying to execute too many commands. We let the running
+ * commands complete or timeout, then try again with a reduced
+ * can_queue. Eventually we will hit the point where we run
+ * on all reserved structs.
+ *
+ * Locking notes: Called with Scsi_Host lock held
+ */
+static void fc_fcp_can_queue_ramp_down(struct fc_lport *lport)
+{
+ struct fc_fcp_internal *si = fc_get_scsi_internal(lport);
+ int can_queue;
+
+ if (si->last_can_queue_ramp_down_time &&
+ (time_before(jiffies, si->last_can_queue_ramp_down_time +
+ FC_CAN_QUEUE_PERIOD)))
+ return;
+
+ si->last_can_queue_ramp_down_time = jiffies;
+
+ can_queue = lport->host->can_queue;
+ can_queue >>= 1;
+ if (!can_queue)
+ can_queue = 1;
+ lport->host->can_queue = can_queue;
+ shost_printk(KERN_ERR, lport->host, "libfc: Could not allocate frame.\n"
+ "Reducing can_queue to %d.\n", can_queue);
+}