[SCSI] qla2xxx: Add FC-transport Asynchronous Event Notification support.

Supported events include LIP, LIP reset, RSCN, link up, and link
down.

To support AEN (and additional forthcoming features), we also
introduce a simple deferred-work construct to manage events which
require a non-atomic sleeping-capable context.  This work-list is
processed as part of the driver's standard DPC routine.

Signed-off-by: Andrew Vasquez <andrew.vasquez@qlogic.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

1 files changed, 73 insertions, 0 deletions

diff --git a/drivers/scsi/qla2xxx/qla_os.c b/drivers/scsi/qla2xxx/qla_os.c
index 661a1596679d..eb77067533ab 100644
--- a/drivers/scsi/qla2xxx/qla_os.c
+++ b/drivers/scsi/qla2xxx/qla_os.c
@@ -1704,6 +1704,7 @@ qla2x00_probe_one(struct pci_dev *pdev, const struct pci_device_id *id)
         INIT_LIST_HEAD(&ha->list);
         INIT_LIST_HEAD(&ha->fcports);
         INIT_LIST_HEAD(&ha->vp_list);
+        INIT_LIST_HEAD(&ha->work_list);
 
         set_bit(0, (unsigned long *) ha->vp_idx_map);
 
@@ -2197,6 +2198,76 @@ qla2x00_mem_free(scsi_qla_host_t *ha)
         kfree(ha->nvram);
 }
 
+struct qla_work_evt *
+qla2x00_alloc_work(struct scsi_qla_host *ha, enum qla_work_type type,
+    int locked)
+{
+        struct qla_work_evt *e;
+
+        e = kzalloc(sizeof(struct qla_work_evt), locked ? GFP_ATOMIC:
+            GFP_KERNEL);
+        if (!e)
+                return NULL;
+
+        INIT_LIST_HEAD(&e->list);
+        e->type = type;
+        e->flags = QLA_EVT_FLAG_FREE;
+        return e;
+}
+
+int
+qla2x00_post_work(struct scsi_qla_host *ha, struct qla_work_evt *e, int locked)
+{
+        unsigned long flags;
+
+        if (!locked)
+                spin_lock_irqsave(&ha->hardware_lock, flags);
+        list_add_tail(&e->list, &ha->work_list);
+        qla2xxx_wake_dpc(ha);
+        if (!locked)
+                spin_unlock_irqrestore(&ha->hardware_lock, flags);
+        return QLA_SUCCESS;
+}
+
+int
+qla2x00_post_aen_work(struct scsi_qla_host *ha, enum fc_host_event_code code,
+    u32 data)
+{
+        struct qla_work_evt *e;
+
+        e = qla2x00_alloc_work(ha, QLA_EVT_AEN, 1);
+        if (!e)
+                return QLA_FUNCTION_FAILED;
+
+        e->u.aen.code = code;
+        e->u.aen.data = data;
+        return qla2x00_post_work(ha, e, 1);
+}
+
+static void
+qla2x00_do_work(struct scsi_qla_host *ha)
+{
+        struct qla_work_evt *e;
+
+        spin_lock_irq(&ha->hardware_lock);
+        while (!list_empty(&ha->work_list)) {
+                e = list_entry(ha->work_list.next, struct qla_work_evt, list);
+                list_del_init(&e->list);
+                spin_unlock_irq(&ha->hardware_lock);
+
+                switch (e->type) {
+                case QLA_EVT_AEN:
+                        fc_host_post_event(ha->host, fc_get_event_number(),
+                            e->u.aen.code, e->u.aen.data);
+                        break;
+                }
+                if (e->flags & QLA_EVT_FLAG_FREE)
+                        kfree(e);
+                spin_lock_irq(&ha->hardware_lock);
+        }
+        spin_unlock_irq(&ha->hardware_lock);
+}
+
 /**************************************************************************
 * qla2x00_do_dpc
 *   This kernel thread is a task that is schedule by the interrupt handler
@@ -2248,6 +2319,8 @@ qla2x00_do_dpc(void *data)
                         continue;
                 }
 
+                qla2x00_do_work(ha);
+
                 if (test_and_clear_bit(ISP_ABORT_NEEDED, &ha->dpc_flags)) {
 
                         DEBUG(printk("scsi(%ld): dpc: sched "