From 928cdb2a034572d29cda884b927cca293baae211 Mon Sep 17 00:00:00 2001
From: Jonathan Bauer
Date: Wed, 4 Apr 2018 17:47:01 +0200
Subject: [KERNEL] Pre/post 4.11 handling of request ops

---
 src/kernel/blk.c | 24 ++++++++++++++++++++----
 src/kernel/net.c | 17 ++++++++++-------
 2 files changed, 30 insertions(+), 11 deletions(-)

(limited to 'src/kernel')

diff --git a/src/kernel/blk.c b/src/kernel/blk.c
index 6f2523c..511d349 100644
--- a/src/kernel/blk.c
+++ b/src/kernel/blk.c
@@ -25,6 +25,22 @@
 
 #include <linux/pagemap.h>
 
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 11, 0)
+#define dnbd3_req_read(req) \
+	req_op(req) == REQ_OP_READ
+#define dnbd3_req_fs(req) \
+	dnbd3_req_read(req) || req_op(req) == REQ_OP_WRITE
+#define dnbd3_req_special(req) \
+	blk_rq_is_private(req)
+#else
+#define dnbd3_req_read(req) \
+	rq_data_dir(req) == READ
+#define dnbd3_req_fs(req) \
+	req->cmd_type == REQ_TYPE_FS
+#define dnbd3_req_special(req) \
+	req->cmd_type == REQ_TYPE_SPECIAL
+#endif
+
 int dnbd3_blk_add_device(dnbd3_device_t *dev, int minor)
 {
 	struct gendisk *disk;
@@ -267,7 +283,7 @@ void dnbd3_blk_request(struct request_queue *q)
 			continue;
 		}
 
-		if (req_op(req) != REQ_OP_READ && req_op(req) != REQ_OP_WRITE)
+		if (!(dnbd3_req_fs(req)))
 		{
 			__blk_end_request_all(req, 0);
 			continue;
@@ -279,7 +295,7 @@ void dnbd3_blk_request(struct request_queue *q)
 			continue;
 		}
 
-		if (req_op(req) != REQ_OP_READ)
+		if (!(dnbd3_req_read(req)))
 		{
 			__blk_end_request_all(req, -EACCES);
 			continue;
@@ -341,13 +357,13 @@ void dnbd3_blk_fail_all_requests(dnbd3_device_t *dev)
 	list_for_each_entry_safe(blk_request, tmp_request, &local_copy, queuelist)
 	{
 		list_del_init(&blk_request->queuelist);
-		if (req_op(blk_request) == REQ_OP_READ || req_op(blk_request) == REQ_OP_WRITE)
+		if (dnbd3_req_fs(blk_request))
 		{
 			spin_lock_irqsave(&dev->blk_lock, flags);
 			__blk_end_request_all(blk_request, -EIO);
 			spin_unlock_irqrestore(&dev->blk_lock, flags);
 		}
-		else if (blk_rq_is_private(blk_request))
+		else if (dnbd3_req_special(blk_request))
 		{
 			kfree(blk_request);
 		}
diff --git a/src/kernel/net.c b/src/kernel/net.c
index 1609258..0b2098d 100644
--- a/src/kernel/net.c
+++ b/src/kernel/net.c
@@ -46,6 +46,9 @@
 // Pack into cmd_flags field by shifting CMD_* into unused bits of cmd_flags
 #define dnbd3_cmd_to_priv(req, cmd)   (req)->cmd_flags = REQ_OP_DRV_IN | ((cmd) << REQ_FLAG_BITS)
 #define dnbd3_priv_to_cmd(req)        ((req)->cmd_flags >> REQ_FLAG_BITS)
+#define dnbd3_req_op(req)             req_op(req)
+#define DNBD3_DEV_READ REQ_OP_READ
+#define DNBD3_REQ_OP_SPECIAL REQ_OP_DRV_IN
 #else
 // Old way with type and flags separated
 #define dnbd3_cmd_to_priv(req, cmd)   do {  \
@@ -53,6 +56,9 @@
 	(req)->cmd_flags = (cmd);                \
 } while (0)
 #define dnbd3_priv_to_cmd(req)        (req)->cmd_flags
+#define dnbd3_req_op(req)             (req)->cmd_type
+#define DNBD3_DEV_READ REQ_TYPE_FS
+#define DNBD3_REQ_OP_SPECIAL REQ_TYPE_SPECIAL
 #endif
 
 /**
@@ -875,10 +881,9 @@ int dnbd3_net_send(void *data)
 		spin_unlock_irqrestore(&dev->blk_lock, irqflags);
 
 		// what to do?
-		switch (req_op(blk_request))
+		switch (dnbd3_req_op(blk_request))
 		{
-		case REQ_OP_READ:
-		case REQ_OP_WRITE:
+		case DNBD3_DEV_READ:
 			dnbd3_request.cmd = CMD_GET_BLOCK;
 			dnbd3_request.offset = blk_rq_pos(blk_request) << 9; // *512
 			dnbd3_request.size = blk_rq_bytes(blk_request); // bytes left to complete entire request
@@ -888,9 +893,7 @@ int dnbd3_net_send(void *data)
 			list_add_tail(&blk_request->queuelist, &dev->request_queue_receive);
 			spin_unlock_irqrestore(&dev->blk_lock, irqflags);
 			break;
-
-		case REQ_OP_DRV_IN:
-		case REQ_OP_DRV_OUT:
+		case DNBD3_REQ_OP_SPECIAL:
 			dnbd3_request.cmd = dnbd3_priv_to_cmd(blk_request);
 			dnbd3_request.size = 0;
 			spin_lock_irqsave(&dev->blk_lock, irqflags);
@@ -899,7 +902,7 @@ int dnbd3_net_send(void *data)
 			break;
 
 		default:
-			printk("ERROR: Unknown command (send %u %u)\n", (int)blk_request->cmd_flags, (int)req_op(blk_request));
+			printk("ERROR: Unknown command (send %u %u)\n", (int)blk_request->cmd_flags, (int)dnbd3_req_op(blk_request));
 			spin_lock_irqsave(&dev->blk_lock, irqflags);
 			list_del_init(&blk_request->queuelist);
 			spin_unlock_irqrestore(&dev->blk_lock, irqflags);
-- 
cgit v1.2.3-55-g7522