From 7c82782252605f2cc287780166ee10442d10e978 Mon Sep 17 00:00:00 2001
From: Dexuan Cui <decui@microsoft.com>
Date: Wed, 27 Jan 2016 22:29:41 -0800
Subject: [PATCH 28/41] Drivers: hv: vmbus: add a hvsock flag in struct
 hv_driver

Only the coming hv_sock driver has a "true" value for this flag.

We treat the hvsock offers/channels as special VMBus devices.
Since the hv_sock driver handles all the hvsock offers/channels, we need to
tweak vmbus_match() for hv_sock driver, so we introduce this flag.

Signed-off-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit 8981da320a11217589aa3c50f9e891bcdef07ece)
---
 drivers/hv/vmbus_drv.c |  4 ++++
 include/linux/hyperv.h | 14 ++++++++++++++
 2 files changed, 18 insertions(+)

diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index 3b83dfe..d76a65f 100644
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -583,6 +583,10 @@ static int vmbus_match(struct device *device, struct device_driver *driver)
 	struct hv_driver *drv = drv_to_hv_drv(driver);
 	struct hv_device *hv_dev = device_to_hv_device(device);
 
+	/* The hv_sock driver handles all hv_sock offers. */
+	if (is_hvsock_channel(hv_dev->channel))
+		return drv->hvsock;
+
 	if (hv_vmbus_get_id(drv->id_table, &hv_dev->dev_type))
 		return 1;
 
diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
index 191bc5d..05966e2 100644
--- a/include/linux/hyperv.h
+++ b/include/linux/hyperv.h
@@ -992,6 +992,20 @@ extern void vmbus_ontimer(unsigned long data);
 struct hv_driver {
 	const char *name;
 
+	/*
+	 * A hvsock offer, which has a VMBUS_CHANNEL_TLNPI_PROVIDER_OFFER
+	 * channel flag, actually doesn't mean a synthetic device because the
+	 * offer's if_type/if_instance can change for every new hvsock
+	 * connection.
+	 *
+	 * However, to facilitate the notification of new-offer/rescind-offer
+	 * from vmbus driver to hvsock driver, we can handle hvsock offer as
+	 * a special vmbus device, and hence we need the below flag to
+	 * indicate if the driver is the hvsock driver or not: we need to
+	 * specially treat the hvosck offer & driver in vmbus_match().
+	 */
+	bool hvsock;
+
 	/* the device type supported by this driver */
 	uuid_le dev_type;
 	const struct hv_vmbus_device_id *id_table;
-- 
2.8.2

