qla4xxx: Export sysfs DDBs from DPC handler

Issue:
modprobe qla4xxx is killed by systemd due to timeout.

Solution:
The exporting of sysfs DDBs from qla4xxx_probe_adapter added delay of
approximately 15s due to which system-udevd killed the modprobe of the
driver. Added fix to export the sysfs DDBs from the DPC handler.

Signed-off-by: Nilesh Javali <nilesh.javali@qlogic.com>
Signed-off-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Christoph Hellwig <hch@lst.de>

drivers/scsi/qla4xxx/ql4_def.h

@@ -601,6 +601,7 @@ struct scsi_qla_host {
 #define DPC_HA_NEED_QUIESCENT		22 /* 0x00400000 ISP-82xx only*/
 #define DPC_POST_IDC_ACK		23 /* 0x00800000 */
 #define DPC_RESTORE_ACB			24 /* 0x01000000 */
+#define DPC_SYSFS_DDB_EXPORT		25 /* 0x02000000 */
 
 	struct Scsi_Host *host; /* pointer to host data */
 	uint32_t tot_ddbs;

drivers/scsi/qla4xxx/ql4_glbl.h

@@ -281,6 +281,7 @@ int qla4_83xx_get_port_config(struct scsi_qla_host *ha, uint32_t *config);
 int qla4_83xx_set_port_config(struct scsi_qla_host *ha, uint32_t *config);
 int qla4_8xxx_check_init_adapter_retry(struct scsi_qla_host *ha);
 int qla4_83xx_is_detached(struct scsi_qla_host *ha);
+int qla4xxx_sysfs_ddb_export(struct scsi_qla_host *ha);
 
 extern int ql4xextended_error_logging;
 extern int ql4xdontresethba;

drivers/scsi/qla4xxx/ql4_os.c

@@ -4565,6 +4565,7 @@ static void qla4xxx_timer(struct scsi_qla_host *ha)
 	     test_bit(DPC_LINK_CHANGED, &ha->dpc_flags) ||
 	     test_bit(DPC_HA_UNRECOVERABLE, &ha->dpc_flags) ||
 	     test_bit(DPC_HA_NEED_QUIESCENT, &ha->dpc_flags) ||
+	     test_bit(DPC_SYSFS_DDB_EXPORT, &ha->dpc_flags) ||
 	     test_bit(DPC_AEN, &ha->dpc_flags)) {
 		DEBUG2(printk("scsi%ld: %s: scheduling dpc routine"
 			      " - dpc flags = 0x%lx\n",
@@ -5429,6 +5430,11 @@ dpc_post_reset_ha:
 				qla4xxx_relogin_all_devices(ha);
 		}
 	}
+	if (test_and_clear_bit(DPC_SYSFS_DDB_EXPORT, &ha->dpc_flags)) {
+		if (qla4xxx_sysfs_ddb_export(ha))
+			ql4_printk(KERN_ERR, ha, "%s: Error exporting ddb to sysfs\n",
+				   __func__);
+	}
 }
 
 /**
@@ -8406,7 +8412,7 @@ exit_ddb_del:
  *
  * Export the firmware DDB for all send targets and normal targets to sysfs.
  **/
-static int qla4xxx_sysfs_ddb_export(struct scsi_qla_host *ha)
+int qla4xxx_sysfs_ddb_export(struct scsi_qla_host *ha)
 {
 	struct dev_db_entry *fw_ddb_entry = NULL;
 	dma_addr_t fw_ddb_entry_dma;
@@ -8844,11 +8850,8 @@ skip_retry_init:
 		ql4_printk(KERN_ERR, ha,
 			   "%s: No iSCSI boot target configured\n", __func__);
 
-	if (qla4xxx_sysfs_ddb_export(ha))
-		ql4_printk(KERN_ERR, ha,
-			   "%s: Error exporting ddb to sysfs\n", __func__);
-
-		/* Perform the build ddb list and login to each */
+	set_bit(DPC_SYSFS_DDB_EXPORT, &ha->dpc_flags);
+	/* Perform the build ddb list and login to each */
 	qla4xxx_build_ddb_list(ha, INIT_ADAPTER);
 	iscsi_host_for_each_session(ha->host, qla4xxx_login_flash_ddb);
 	qla4xxx_wait_login_resp_boot_tgt(ha);