diff options
Diffstat (limited to 'drivers/hv/hv_snapshot.c')
| -rw-r--r-- | drivers/hv/hv_snapshot.c | 36 |
1 files changed, 17 insertions, 19 deletions
diff --git a/drivers/hv/hv_snapshot.c b/drivers/hv/hv_snapshot.c index 815405f2e777..67def4a831c8 100644 --- a/drivers/hv/hv_snapshot.c +++ b/drivers/hv/hv_snapshot.c @@ -53,7 +53,6 @@ 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; @@ -74,6 +73,13 @@ static void vss_timeout_func(struct work_struct *dummy); static DECLARE_DELAYED_WORK(vss_timeout_work, vss_timeout_func); static DECLARE_WORK(vss_send_op_work, vss_send_op); +static void vss_poll_wrapper(void *channel) +{ + /* Transaction is finished, reset the state here to avoid races. */ + vss_transaction.state = HVUTIL_READY; + hv_vss_onchannelcallback(channel); +} + /* * Callback when data is received from user mode. */ @@ -86,12 +92,7 @@ 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); - /* Transaction is finished, reset the state. */ - if (vss_transaction.state > HVUTIL_READY) - vss_transaction.state = HVUTIL_READY; - - hv_poll_channel(vss_transaction.vss_context, - hv_vss_onchannelcallback); + hv_poll_channel(vss_transaction.recv_channel, vss_poll_wrapper); } static int vss_handle_handshake(struct hv_vss_msg *vss_msg) @@ -112,7 +113,7 @@ static int vss_handle_handshake(struct hv_vss_msg *vss_msg) default: return -EINVAL; } - vss_transaction.state = HVUTIL_READY; + hv_poll_channel(vss_transaction.recv_channel, vss_poll_wrapper); pr_debug("VSS: userspace daemon ver. %d registered\n", dm_reg_value); return 0; } @@ -138,9 +139,8 @@ static int vss_on_msg(void *msg, int len) if (cancel_delayed_work_sync(&vss_timeout_work)) { vss_respond_to_host(vss_msg->error); /* Transaction is finished, reset the state. */ - vss_transaction.state = HVUTIL_READY; - hv_poll_channel(vss_transaction.vss_context, - hv_vss_onchannelcallback); + hv_poll_channel(vss_transaction.recv_channel, + vss_poll_wrapper); } } else { /* This is a spurious call! */ @@ -238,15 +238,8 @@ void hv_vss_onchannelcallback(void *context) struct icmsg_hdr *icmsghdrp; struct icmsg_negotiate *negop = NULL; - if (vss_transaction.state > HVUTIL_READY) { - /* - * We will defer processing this callback once - * the current transaction is complete. - */ - vss_transaction.vss_context = context; + if (vss_transaction.state > HVUTIL_READY) return; - } - vss_transaction.vss_context = NULL; vmbus_recvpacket(channel, recv_buffer, PAGE_SIZE * 2, &recvlen, &requestid); @@ -338,6 +331,11 @@ static void vss_on_reset(void) int hv_vss_init(struct hv_util_service *srv) { + if (vmbus_proto_version < VERSION_WIN8_1) { + pr_warn("Integration service 'Backup (volume snapshot)'" + " not supported on this host version.\n"); + return -ENOTSUPP; + } recv_buffer = srv->recv_buffer; /* |