When we need to pass a buffer with Hyper-V message we don't need to always
allocate 256 bytes for the message: the real message length is known from
the header. Change 'struct onmessage_work_context' to make it possible to
not over-allocate.
Signed-off-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
---
drivers/hv/vmbus_drv.c | 15 ++++++++++-----
1 file changed, 10 insertions(+), 5 deletions(-)
diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index 2b5572146358..642782bef863 100644
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -991,7 +991,10 @@ static struct bus_type hv_bus = {
struct onmessage_work_context {
struct work_struct work;
- struct hv_message msg;
+ struct {
+ struct hv_message_header header;
+ u8 payload[];
+ } msg;
};
static void vmbus_onmessage_work(struct work_struct *work)
@@ -1038,7 +1041,8 @@ void vmbus_on_msg_dpc(unsigned long data)
goto msg_handled;
if (entry->handler_type == VMHT_BLOCKING) {
- ctx = kmalloc(sizeof(*ctx), GFP_ATOMIC);
+ ctx = kmalloc(sizeof(*ctx) + msg->header.payload_size,
+ GFP_ATOMIC);
if (ctx == NULL)
return;
@@ -1092,10 +1096,11 @@ static void vmbus_force_channel_rescinded(struct vmbus_channel *channel)
WARN_ON(!is_hvsock_channel(channel));
/*
- * sizeof(*ctx) is small and the allocation should really not fail,
+ * Allocation size is small and the allocation should really not fail,
* otherwise the state of the hv_sock connections ends up in limbo.
*/
- ctx = kzalloc(sizeof(*ctx), GFP_KERNEL | __GFP_NOFAIL);
+ ctx = kzalloc(sizeof(*ctx) + sizeof(*rescind),
+ GFP_KERNEL | __GFP_NOFAIL);
/*
* So far, these are not really used by Linux. Just set them to the
@@ -1105,7 +1110,7 @@ static void vmbus_force_channel_rescinded(struct vmbus_channel *channel)
ctx->msg.header.payload_size = sizeof(*rescind);
/* These values are actually used by Linux. */
- rescind = (struct vmbus_channel_rescind_offer *)ctx->msg.u.payload;
+ rescind = (struct vmbus_channel_rescind_offer *)ctx->msg.payload;
rescind->header.msgtype = CHANNELMSG_RESCIND_CHANNELOFFER;
rescind->child_relid = channel->offermsg.child_relid;
--
2.25.1
