[PATCH V2 11/13] Drivers: hv: vmbus: add an API vmbus_hvsock_device_unregister()

K. Y. Srinivasan
2016-01-28T04:55:03Z

From: Dexuan Cui <decui@microsoft.com>

The hvsock driver needs this API to release all the resources related
to the channel.

Signed-off-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
---
drivers/hv/channel_mgmt.c | 33 ++++++++++++++++++++++++++++-----
drivers/hv/connection.c | 4 ++--
include/linux/hyperv.h | 2 ++
3 files changed, 32 insertions(+), 7 deletions(-)

diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c
index 76864c9..cf311be 100644
--- a/drivers/hv/channel_mgmt.c
+++ b/drivers/hv/channel_mgmt.c
@@ -310,6 +310,7 @@ void hv_process_channel_removal(struct vmbus_channel *channel, u32 relid)
vmbus_release_relid(relid);

BUG_ON(!channel->rescind);
+ BUG_ON(!mutex_is_locked(&vmbus_connection.channel_mutex));

if (channel->target_cpu != get_cpu()) {
put_cpu();
@@ -321,9 +322,7 @@ void hv_process_channel_removal(struct vmbus_channel *channel, u32 relid)
}

if (channel->primary_channel == NULL) {
- mutex_lock(&vmbus_connection.channel_mutex);
list_del(&channel->listentry);
- mutex_unlock(&vmbus_connection.channel_mutex);

primary_channel = channel;
} else {
@@ -367,6 +366,7 @@ static void vmbus_process_offer(struct vmbus_channel *newchannel)
bool fnew = true;
unsigned long flags;
u16 dev_type;
+ int ret;

/* Make sure this is a new offer */
mutex_lock(&vmbus_connection.channel_mutex);
@@ -449,7 +449,11 @@ static void vmbus_process_offer(struct vmbus_channel *newchannel)
* binding which eventually invokes the device driver's AddDevice()
* method.
*/
- if (vmbus_device_register(newchannel->device_obj) != 0) {
+ mutex_lock(&vmbus_connection.channel_mutex);
+ ret = vmbus_device_register(newchannel->device_obj);
+ mutex_unlock(&vmbus_connection.channel_mutex);
+
+ if (ret != 0) {
pr_err("unable to add child device object (relid %d)\n",
newchannel->offermsg.child_relid);
kfree(newchannel->device_obj);
@@ -725,6 +729,8 @@ static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr)
struct device *dev;

rescind = (struct vmbus_channel_rescind_offer *)hdr;
+
+ mutex_lock(&vmbus_connection.channel_mutex);
channel = relid2channel(rescind->child_relid);

if (channel == NULL) {
@@ -733,7 +739,7 @@ static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr)
* vmbus_process_offer(), we have already invoked
* vmbus_release_relid() on error.
*/
- return;
+ goto out;
}

spin_lock_irqsave(&channel->lock, flags);
@@ -743,7 +749,7 @@ static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr)
if (channel->device_obj) {
if (channel->chn_rescind_callback) {
channel->chn_rescind_callback(channel);
- return;
+ goto out;
}
/*
* We will have to unregister this device from the
@@ -758,8 +764,25 @@ static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr)
hv_process_channel_removal(channel,
channel->offermsg.child_relid);
}
+
+out:
+ mutex_unlock(&vmbus_connection.channel_mutex);
}

+void vmbus_hvsock_device_unregister(struct vmbus_channel *channel)
+{
+ mutex_lock(&vmbus_connection.channel_mutex);
+
+ BUG_ON(!is_hvsock_channel(channel));
+
+ channel->rescind = true;
+ vmbus_device_unregister(channel->device_obj);
+
+ mutex_unlock(&vmbus_connection.channel_mutex);
+}
+EXPORT_SYMBOL_GPL(vmbus_hvsock_device_unregister);
+
+
/*
* vmbus_onoffers_delivered -
* This is invoked when all offers have been delivered.
diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c
index 3dc5a9c..deb48e6 100644
--- a/drivers/hv/connection.c
+++ b/drivers/hv/connection.c
@@ -288,7 +288,8 @@ struct vmbus_channel *relid2channel(u32 relid)
struct list_head *cur, *tmp;
struct vmbus_channel *cur_sc;

- mutex_lock(&vmbus_connection.channel_mutex);
+ BUG_ON(!mutex_is_locked(&vmbus_connection.channel_mutex));
+
list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) {
if (channel->offermsg.child_relid == relid) {
found_channel = channel;
@@ -307,7 +308,6 @@ struct vmbus_channel *relid2channel(u32 relid)
}
}
}
- mutex_unlock(&vmbus_connection.channel_mutex);

return found_channel;
}
diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
index 2e54e34..c056f05 100644
--- a/include/linux/hyperv.h
+++ b/include/linux/hyperv.h
@@ -1069,6 +1069,8 @@ int __must_check __vmbus_driver_register(struct hv_driver *hv_driver,
const char *mod_name);
void vmbus_driver_unregister(struct hv_driver *hv_driver);

+void vmbus_hvsock_device_unregister(struct vmbus_channel *channel);
+
int vmbus_allocate_mmio(struct resource **new, struct hv_device *device_obj,
resource_size_t min, resource_size_t max,
resource_size_t size, resource_size_t align,
--
1.7.4.1