From 993f290908b6954eb330c2eb4408f63f6a3f1a73 Mon Sep 17 00:00:00 2001
From: Bart Van Assche <bart.vanassche@sandisk.com>
Date: Fri, 10 Jul 2015 22:27:37 +0000
Subject: [PATCH] isert-scst: Port this driver to RHEL 5

git-svn-id: http://svn.code.sf.net/p/scst/svn/trunk@6416 d57e44dd-8a1f-0410-8b47-8ef2f437770f
---
 iscsi-scst/kernel/isert-scst/iser.h        |  7 +++++++
 iscsi-scst/kernel/isert-scst/iser_rdma.c   | 18 +++++++++++++++---
 iscsi-scst/kernel/isert-scst/isert_login.c | 15 +++++++++++++--
 3 files changed, 35 insertions(+), 5 deletions(-)

diff --git a/iscsi-scst/kernel/isert-scst/iser.h b/iscsi-scst/kernel/isert-scst/iser.h
index c01e6af67..b6e77d0bd 100644
--- a/iscsi-scst/kernel/isert-scst/iser.h
+++ b/iscsi-scst/kernel/isert-scst/iser.h
@@ -40,6 +40,13 @@
 #include <linux/interrupt.h>
 #include <linux/workqueue.h>
 #include <rdma/ib_verbs.h>
+#if defined(RHEL_MAJOR) && RHEL_MAJOR -0 == 5
+static inline u16 vlan_dev_vlan_id(const void *dev)
+{
+	BUG();
+	return 0;
+}
+#endif
 #include <rdma/rdma_cm.h>
 
 #include "iser_hdr.h"
diff --git a/iscsi-scst/kernel/isert-scst/iser_rdma.c b/iscsi-scst/kernel/isert-scst/iser_rdma.c
index a2b763ba5..d739374d4 100644
--- a/iscsi-scst/kernel/isert-scst/iser_rdma.c
+++ b/iscsi-scst/kernel/isert-scst/iser_rdma.c
@@ -604,14 +604,21 @@ static int isert_poll_cq(struct isert_cq *cq)
 }
 
 /* callback function for isert_dev->[cq]->cq_comp_work */
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 20) && !defined(BACKPORT_LINUX_WORKQUEUE_TO_2_6_19)
+/* A vanilla 2.6.19 or older kernel without backported OFED kernel headers. */
+static void isert_cq_comp_work_cb(void *ctx)
+{
+	struct isert_cq *cq_desc = ctx;
+#else
 static void isert_cq_comp_work_cb(struct work_struct *work)
 {
-	struct isert_cq *cq_desc;
+	struct isert_cq *cq_desc =
+		container_of(work, struct isert_cq, cq_comp_work);
+#endif
 	int ret;
 
 	TRACE_ENTRY();
 
-	cq_desc = container_of(work, struct isert_cq, cq_comp_work);
 	ret = isert_poll_cq(cq_desc);
 	if (unlikely(ret < 0)) { /* poll error */
 		pr_err("ib_poll_cq failed\n");
@@ -636,8 +643,12 @@ static void isert_cq_comp_handler(struct ib_cq *cq, void *context)
 {
 	struct isert_cq *cq_desc = context;
 
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 20)
+	queue_work(cq_desc->cq_workqueue, &cq_desc->cq_comp_work);
+#else
 	queue_work_on(smp_processor_id(), cq_desc->cq_workqueue,
 		      &cq_desc->cq_comp_work);
+#endif
 }
 
 static const char *ib_event_type_str(enum ib_event_type ev_type)
@@ -1571,7 +1582,8 @@ struct isert_portal *isert_portal_create(void)
 		goto err_alloc;
 	}
 
-#if LINUX_VERSION_CODE < KERNEL_VERSION(3, 0, 0) && !defined(RHEL_MAJOR)
+#if LINUX_VERSION_CODE < KERNEL_VERSION(3, 0, 0) && \
+	(!defined(RHEL_MAJOR) || RHEL_MAJOR -0 <= 5)
 	cm_id = rdma_create_id(isert_cm_evt_handler, portal, RDMA_PS_TCP);
 #else
 	cm_id = rdma_create_id(isert_cm_evt_handler, portal, RDMA_PS_TCP,
diff --git a/iscsi-scst/kernel/isert-scst/isert_login.c b/iscsi-scst/kernel/isert-scst/isert_login.c
index f0d6c25bf..158574793 100644
--- a/iscsi-scst/kernel/isert-scst/isert_login.c
+++ b/iscsi-scst/kernel/isert-scst/isert_login.c
@@ -38,7 +38,12 @@
 #include <linux/fs.h>		/* everything... */
 #include <linux/errno.h>	/* error codes */
 #include <linux/poll.h>
+#include <linux/version.h>
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 20)
 #include <linux/freezer.h>
+#else
+#define wait_event_freezable(wq, cond) ({ wait_event(wq, cond); 0; })
+#endif
 #include <linux/file.h>
 #include "isert_dbg.h"
 #include "../iscsi.h"
@@ -887,7 +892,10 @@ static void __init isert_setup_cdev(struct isert_conn_dev *dev,
 		PRINT_ERROR("Error %d adding "ISER_CONN_DEV_PREFIX"%d", err,
 			    index);
 
-	dev->dev = device_create(isert_class, NULL, dev->devno, NULL,
+	dev->dev = device_create(isert_class, NULL, dev->devno,
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 27)
+				 NULL,
+#endif
 				 ISER_CONN_DEV_PREFIX"%d", index);
 
 	TRACE_EXIT();
@@ -914,7 +922,10 @@ static void __init isert_setup_listener_cdev(struct isert_listener_dev *dev)
 	if (unlikely(err))
 		PRINT_ERROR("Error %d adding isert_scst", err);
 
-	dev->dev = device_create(isert_class, NULL, dev->devno, NULL,
+	dev->dev = device_create(isert_class, NULL, dev->devno,
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 27)
+				 NULL,
+#endif
 				 "isert_scst");
 
 	TRACE_EXIT();