[PATCH 10/13] Drivers: hv: vmbus: add a per-channel rescind callback

From: K. Y. Srinivasan
Date: Wed Jan 27 2016 - 17:51:34 EST


From: Dexuan Cui <decui@xxxxxxxxxxxxx>

This will be used by the coming hv_sock driver.

Signed-off-by: Dexuan Cui <decui@xxxxxxxxxxxxx>
Signed-off-by: K. Y. Srinivasan <kys@xxxxxxxxxxxxx>
---
drivers/hv/channel_mgmt.c | 11 +++++++++++
include/linux/hyperv.h | 9 +++++++++
2 files changed, 20 insertions(+), 0 deletions(-)

diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c
index 60ca25b..76864c9 100644
--- a/drivers/hv/channel_mgmt.c
+++ b/drivers/hv/channel_mgmt.c
@@ -741,6 +741,10 @@ static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr)
spin_unlock_irqrestore(&channel->lock, flags);

if (channel->device_obj) {
+ if (channel->chn_rescind_callback) {
+ channel->chn_rescind_callback(channel);
+ return;
+ }
/*
* We will have to unregister this device from the
* driver core.
@@ -1110,3 +1114,10 @@ bool vmbus_are_subchannels_present(struct vmbus_channel *primary)
return ret;
}
EXPORT_SYMBOL_GPL(vmbus_are_subchannels_present);
+
+void vmbus_set_chn_rescind_callback(struct vmbus_channel *channel,
+ void (*chn_rescind_cb)(struct vmbus_channel *))
+{
+ channel->chn_rescind_callback = chn_rescind_cb;
+}
+EXPORT_SYMBOL_GPL(vmbus_set_chn_rescind_callback);
diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
index f636f91..2e54e34 100644
--- a/include/linux/hyperv.h
+++ b/include/linux/hyperv.h
@@ -766,6 +766,12 @@ struct vmbus_channel {
void (*sc_creation_callback)(struct vmbus_channel *new_sc);

/*
+ * Channel rescind callback. Some channels (the hvsock ones), need to
+ * register a callback which is invoked in vmbus_onoffer_rescind().
+ */
+ void (*chn_rescind_callback)(struct vmbus_channel *channel);
+
+ /*
* The spinlock to protect the structure. It is being used to protect
* test-and-set access to various attributes of the structure as well
* as all sc_list operations.
@@ -851,6 +857,9 @@ int vmbus_request_offers(void);
void vmbus_set_sc_create_callback(struct vmbus_channel *primary_channel,
void (*sc_cr_cb)(struct vmbus_channel *new_sc));

+void vmbus_set_chn_rescind_callback(struct vmbus_channel *channel,
+ void (*chn_rescind_cb)(struct vmbus_channel *));
+
/*
* Retrieve the (sub) channel on which to send an outgoing request.
* When a primary channel has multiple sub-channels, we choose a
--
1.7.4.1