[SCSI] qla4xxx: added support for host event

Added support to post kernel host event to application using
netlink interface.

Signed-off-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

4 files changed, 111 insertions, 0 deletions

diff --git a/drivers/scsi/qla4xxx/ql4_def.h b/drivers/scsi/qla4xxx/ql4_def.h
index ec48dc30b9a2..f91808ce572e 100644
--- a/drivers/scsi/qla4xxx/ql4_def.h
+++ b/drivers/scsi/qla4xxx/ql4_def.h
@@ -301,7 +301,21 @@ struct ql4_tuple_ddb {
 #define DF_ISNS_DISCOVERED      2       /* Device was discovered via iSNS */
 #define DF_FO_MASKED            3
 
+enum qla4_work_type {
+        QLA4_EVENT_AEN,
+};
 
+struct qla4_work_evt {
+        struct list_head list;
+        enum qla4_work_type type;
+        union {
+                struct {
+                        enum iscsi_host_event_code code;
+                        uint32_t data_size;
+                        uint8_t data[0];
+                } aen;
+        } u;
+};
 
 struct ql82xx_hw_data {
         /* Offsets for flash/nvram access (set to ~0 if not used). */
@@ -672,6 +686,10 @@ struct scsi_qla_host {
         uint16_t sec_ddb_idx;
         int is_reset;
         uint16_t temperature;
+
+        /* event work list */
+        struct list_head work_list;
+        spinlock_t work_lock;
 };
 
 struct ql4_task_data {
diff --git a/drivers/scsi/qla4xxx/ql4_glbl.h b/drivers/scsi/qla4xxx/ql4_glbl.h
index d0dd4b330206..34cf851978e9 100644
--- a/drivers/scsi/qla4xxx/ql4_glbl.h
+++ b/drivers/scsi/qla4xxx/ql4_glbl.h
@@ -181,6 +181,8 @@ int qla4xxx_flash_ddb_change(struct scsi_qla_host *ha, uint32_t fw_ddb_index,
 int qla4xxx_ddb_change(struct scsi_qla_host *ha, uint32_t fw_ddb_index,
                        struct ddb_entry *ddb_entry, uint32_t state);
 void qla4xxx_build_ddb_list(struct scsi_qla_host *ha, int is_reset);
+int qla4xxx_post_aen_work(struct scsi_qla_host *ha, uint32_t aen_code,
+                          uint32_t data_size, uint8_t *data);
 
 /* BSG Functions */
 int qla4xxx_bsg_request(struct bsg_job *bsg_job);
diff --git a/drivers/scsi/qla4xxx/ql4_isr.c b/drivers/scsi/qla4xxx/ql4_isr.c
index 95828862eea0..954fe84be575 100644
--- a/drivers/scsi/qla4xxx/ql4_isr.c
+++ b/drivers/scsi/qla4xxx/ql4_isr.c
@@ -576,6 +576,9 @@ static void qla4xxx_isr_decode_mailbox(struct scsi_qla_host * ha,
                                 set_bit(DPC_LINK_CHANGED, &ha->dpc_flags);
 
                         ql4_printk(KERN_INFO, ha, "%s: LINK UP\n", __func__);
+                        qla4xxx_post_aen_work(ha, ISCSI_EVENT_LINKUP,
+                                              sizeof(mbox_sts),
+                                              (uint8_t *) mbox_sts);
                         break;
 
                 case MBOX_ASTS_LINK_DOWN:
@@ -584,6 +587,9 @@ static void qla4xxx_isr_decode_mailbox(struct scsi_qla_host * ha,
                                 set_bit(DPC_LINK_CHANGED, &ha->dpc_flags);
 
                         ql4_printk(KERN_INFO, ha, "%s: LINK DOWN\n", __func__);
+                        qla4xxx_post_aen_work(ha, ISCSI_EVENT_LINKDOWN,
+                                              sizeof(mbox_sts),
+                                              (uint8_t *) mbox_sts);
                         break;
 
                 case MBOX_ASTS_HEARTBEAT:
diff --git a/drivers/scsi/qla4xxx/ql4_os.c b/drivers/scsi/qla4xxx/ql4_os.c
index 2cd20775836f..d423f7afbbd7 100644
--- a/drivers/scsi/qla4xxx/ql4_os.c
+++ b/drivers/scsi/qla4xxx/ql4_os.c
@@ -2282,6 +2282,10 @@ static void qla4xxx_timer(struct scsi_qla_host *ha)
                 }
         }
 
+        /* Process any deferred work. */
+        if (!list_empty(&ha->work_list))
+                start_dpc++;
+
         /* Wakeup the dpc routine for this adapter, if needed. */
         if (start_dpc ||
              test_bit(DPC_RESET_HA, &ha->dpc_flags) ||
@@ -2847,6 +2851,81 @@ void qla4xxx_wake_dpc(struct scsi_qla_host *ha)
                 queue_work(ha->dpc_thread, &ha->dpc_work);
 }
 
+static struct qla4_work_evt *
+qla4xxx_alloc_work(struct scsi_qla_host *ha, uint32_t data_size,
+                   enum qla4_work_type type)
+{
+        struct qla4_work_evt *e;
+        uint32_t size = sizeof(struct qla4_work_evt) + data_size;
+
+        e = kzalloc(size, GFP_ATOMIC);
+        if (!e)
+                return NULL;
+
+        INIT_LIST_HEAD(&e->list);
+        e->type = type;
+        return e;
+}
+
+static void qla4xxx_post_work(struct scsi_qla_host *ha,
+                             struct qla4_work_evt *e)
+{
+        unsigned long flags;
+
+        spin_lock_irqsave(&ha->work_lock, flags);
+        list_add_tail(&e->list, &ha->work_list);
+        spin_unlock_irqrestore(&ha->work_lock, flags);
+        qla4xxx_wake_dpc(ha);
+}
+
+int qla4xxx_post_aen_work(struct scsi_qla_host *ha,
+                          enum iscsi_host_event_code aen_code,
+                          uint32_t data_size, uint8_t *data)
+{
+        struct qla4_work_evt *e;
+
+        e = qla4xxx_alloc_work(ha, data_size, QLA4_EVENT_AEN);
+        if (!e)
+                return QLA_ERROR;
+
+        e->u.aen.code = aen_code;
+        e->u.aen.data_size = data_size;
+        memcpy(e->u.aen.data, data, data_size);
+
+        qla4xxx_post_work(ha, e);
+
+        return QLA_SUCCESS;
+}
+
+void qla4xxx_do_work(struct scsi_qla_host *ha)
+{
+        struct qla4_work_evt *e, *tmp;
+        unsigned long flags;
+        LIST_HEAD(work);
+
+        spin_lock_irqsave(&ha->work_lock, flags);
+        list_splice_init(&ha->work_list, &work);
+        spin_unlock_irqrestore(&ha->work_lock, flags);
+
+        list_for_each_entry_safe(e, tmp, &work, list) {
+                list_del_init(&e->list);
+
+                switch (e->type) {
+                case QLA4_EVENT_AEN:
+                        iscsi_post_host_event(ha->host_no,
+                                              &qla4xxx_iscsi_transport,
+                                              e->u.aen.code,
+                                              e->u.aen.data_size,
+                                              e->u.aen.data);
+                        break;
+                default:
+                        ql4_printk(KERN_WARNING, ha, "event type: 0x%x not "
+                                   "supported", e->type);
+                }
+                kfree(e);
+        }
+}
+
 /**
  * qla4xxx_do_dpc - dpc routine
  * @data: in our case pointer to adapter structure
@@ -2878,6 +2957,9 @@ static void qla4xxx_do_dpc(struct work_struct *work)
                 return;
         }
 
+        /* post events to application */
+        qla4xxx_do_work(ha);
+
         if (is_qla8022(ha)) {
                 if (test_bit(DPC_HA_UNRECOVERABLE, &ha->dpc_flags)) {
                         qla4_8xxx_idc_lock(ha);
@@ -4450,6 +4532,9 @@ static int __devinit qla4xxx_probe_adapter(struct pci_dev *pdev,
 
         spin_lock_init(&ha->hardware_lock);
 
+        /* Initialize work list */
+        INIT_LIST_HEAD(&ha->work_list);
+
         /* Allocate dma buffers */
         if (qla4xxx_mem_alloc(ha)) {
                 ql4_printk(KERN_WARNING, ha,