[PATCH RFCv2 05/21] Drivers: hv: vss: process deferred messages when we complete the transaction
From: Vitaly Kuznetsov <vkuznets@redhat.com>
Date: 2015-03-11 13:30:11
Also in:
lkml
Subsystem:
hyper-v/azure core and drivers, the rest · Maintainers:
"K. Y. Srinivasan", Haiyang Zhang, Wei Liu, Dexuan Cui, Long Li, Linus Torvalds
In theory, the host is not supposed to issue any requests before be reply to the previous one. In KVP we, however, support the following scenarios: 1) A message was received before userspace daemon registered; 2) A message was received while the previous one is still being processed. In VSS we support only the former. Add support for the later, use hv_poll_channel() to do the job. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> --- drivers/hv/hv_snapshot.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-)
diff --git a/drivers/hv/hv_snapshot.c b/drivers/hv/hv_snapshot.c
index c1a3604..4bb9b1c 100644
--- a/drivers/hv/hv_snapshot.c
+++ b/drivers/hv/hv_snapshot.c@@ -47,6 +47,7 @@ static struct { struct vmbus_channel *recv_channel; /* chn we got the request */ u64 recv_req_id; /* request ID. */ struct hv_vss_msg *msg; /* current message */ + void *vss_context; /* for the channel callback */ } vss_transaction;
@@ -73,6 +74,9 @@ static void vss_timeout_func(struct work_struct *dummy) */ pr_warn("VSS: timeout waiting for daemon to reply\n"); vss_respond_to_host(HV_E_FAIL); + + hv_poll_channel(vss_transaction.vss_context, + hv_vss_onchannelcallback); } static void
@@ -85,13 +89,12 @@ vss_cn_callback(struct cn_msg *msg, struct netlink_skb_parms *nsp) if (vss_msg->vss_hdr.operation == VSS_OP_REGISTER) { pr_info("VSS daemon registered\n"); vss_transaction.active = false; - if (vss_transaction.recv_channel != NULL) - hv_vss_onchannelcallback(vss_transaction.recv_channel); - return; - } if (cancel_delayed_work_sync(&vss_timeout_work)) vss_respond_to_host(vss_msg->error); + + hv_poll_channel(vss_transaction.vss_context, + hv_vss_onchannelcallback); }
@@ -198,9 +201,10 @@ void hv_vss_onchannelcallback(void *context) * We will defer processing this callback once * the current transaction is complete. */ - vss_transaction.recv_channel = channel; + vss_transaction.vss_context = context; return; } + vss_transaction.vss_context = NULL; vmbus_recvpacket(channel, recv_buffer, PAGE_SIZE * 2, &recvlen, &requestid);
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1.9.3