From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754576AbcHSBAW (ORCPT ); Thu, 18 Aug 2016 21:00:22 -0400 Received: from p3plsmtps2ded04.prod.phx3.secureserver.net ([208.109.80.198]:46650 "EHLO p3plsmtps2ded04.prod.phx3.secureserver.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754561AbcHSBAT (ORCPT ); Thu, 18 Aug 2016 21:00:19 -0400 x-originating-ip: 72.167.245.219 From: kys@exchange.microsoft.com To: gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, devel@linuxdriverproject.org, olaf@aepfle.de, apw@canonical.com, vkuznets@redhat.com, jasowang@redhat.com, leann.ogasawara@canonical.com Cc: Alex Ng , "K. Y. Srinivasan" Subject: [PATCH 1/2] Drivers: hv: utils: Continue to poll VSS channel after handling requests. Date: Thu, 18 Aug 2016 11:16:54 -0700 Message-Id: <1471544215-13999-1-git-send-email-kys@exchange.microsoft.com> X-Mailer: git-send-email 1.7.4.1 In-Reply-To: <1471544167-13952-1-git-send-email-kys@exchange.microsoft.com> References: <1471544167-13952-1-git-send-email-kys@exchange.microsoft.com> Reply-To: kys@microsoft.com X-CMAE-Envelope: MS4wfNQz3Pt/chP59tCF/ru64GdRau3Yp3p7o2dlu0msJkNb22GYcI6K+nf1J+SmsFh5ldd2s60OfsCi4D5q5giZB3TWVIQOnUwd9AI7xu6TvhyOGNMB8U6V QMjIpWnDS2C+ET+AH/nwEXuck3PxM5IQkkxmd+OFNgkk2OPabi3WVe9p7kE6NSBqBeqzdTwASPMz3TRIk1XH2bSNp6LeZ4QTYPffG9F46rgJIgCIBdjR4mSb vYWfECJ/XaTWJidFg2F7j9mXvhjylCUXgFS5S71zU2CVA3coCRD63Nj3c6LkMIWkr9pRpREISCGO57F709huHhyqo0WsS7qk/xlWvxcubRU/lWiSoPMHKN9u j48PyBY+5vJYa/Numn1mHXGTHirpu6kTeAOM1mA0ZZ/jJeoPTphSRF7OOmqtaEGL6hw8y+1PCC2Ub83MNUB11veUSeQdgTNqpsNHtCOFs1qxHK5Ey+Q9sEED UfZ2QZdAc3zi2ztZ Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Alex Ng Multiple VSS_OP_HOT_BACKUP requests may arrive in quick succession, even though the host only signals once. The driver wass handling the first request while ignoring the others in the ring buffer. We should poll the VSS channel after handling a request to continue processing other requests. Signed-off-by: Alex Ng Signed-off-by: K. Y. Srinivasan --- drivers/hv/hv_snapshot.c | 89 +++++++++++++++++++++------------------------ 1 files changed, 42 insertions(+), 47 deletions(-) diff --git a/drivers/hv/hv_snapshot.c b/drivers/hv/hv_snapshot.c index 3fba14e..4c8dd20 100644 --- a/drivers/hv/hv_snapshot.c +++ b/drivers/hv/hv_snapshot.c @@ -67,11 +67,11 @@ static const char vss_devname[] = "vmbus/hv_vss"; static __u8 *recv_buffer; static struct hvutil_transport *hvt; -static void vss_send_op(struct work_struct *dummy); static void vss_timeout_func(struct work_struct *dummy); +static void vss_handle_request(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 DECLARE_WORK(vss_handle_request_work, vss_handle_request); static void vss_poll_wrapper(void *channel) { @@ -150,8 +150,7 @@ static int vss_on_msg(void *msg, int len) return 0; } - -static void vss_send_op(struct work_struct *dummy) +static void vss_send_op(void) { int op = vss_transaction.msg->vss_hdr.operation; int rc; @@ -168,6 +167,8 @@ static void vss_send_op(struct work_struct *dummy) vss_msg->vss_hdr.operation = op; vss_transaction.state = HVUTIL_USERSPACE_REQ; + + schedule_delayed_work(&vss_timeout_work, VSS_USERSPACE_TIMEOUT); rc = hvutil_transport_send(hvt, vss_msg, sizeof(*vss_msg)); if (rc) { pr_warn("VSS: failed to communicate to the daemon: %d\n", rc); @@ -182,6 +183,40 @@ static void vss_send_op(struct work_struct *dummy) return; } +static void vss_handle_request(struct work_struct *dummy) +{ + switch (vss_transaction.msg->vss_hdr.operation) { + /* + * Initiate a "freeze/thaw" operation in the guest. + * We respond to the host once the operation is complete. + * + * We send the message to the user space daemon and the operation is + * performed in the daemon. + */ + case VSS_OP_THAW: + case VSS_OP_FREEZE: + if (vss_transaction.state < HVUTIL_READY) { + /* Userspace is not registered yet */ + vss_respond_to_host(HV_E_FAIL); + return; + } + vss_transaction.state = HVUTIL_HOSTMSG_RECEIVED; + vss_send_op(); + return; + case VSS_OP_HOT_BACKUP: + vss_transaction.msg->vss_cf.flags = VSS_HBU_NO_AUTO_RECOVERY; + break; + case VSS_OP_GET_DM_INFO: + vss_transaction.msg->dm_info.flags = 0; + break; + default: + break; + } + + vss_respond_to_host(0); + hv_poll_channel(vss_transaction.recv_channel, vss_poll_wrapper); +} + /* * Send a response back to the host. */ @@ -266,48 +301,8 @@ void hv_vss_onchannelcallback(void *context) vss_transaction.recv_req_id = requestid; vss_transaction.msg = (struct hv_vss_msg *)vss_msg; - switch (vss_msg->vss_hdr.operation) { - /* - * Initiate a "freeze/thaw" - * operation in the guest. - * We respond to the host once - * the operation is complete. - * - * We send the message to the - * user space daemon and the - * operation is performed in - * the daemon. - */ - case VSS_OP_FREEZE: - case VSS_OP_THAW: - if (vss_transaction.state < HVUTIL_READY) { - /* Userspace is not registered yet */ - vss_respond_to_host(HV_E_FAIL); - return; - } - vss_transaction.state = HVUTIL_HOSTMSG_RECEIVED; - schedule_work(&vss_send_op_work); - schedule_delayed_work(&vss_timeout_work, - VSS_USERSPACE_TIMEOUT); - return; - - case VSS_OP_HOT_BACKUP: - vss_msg->vss_cf.flags = - VSS_HBU_NO_AUTO_RECOVERY; - vss_respond_to_host(0); - return; - - case VSS_OP_GET_DM_INFO: - vss_msg->dm_info.flags = 0; - vss_respond_to_host(0); - return; - - default: - vss_respond_to_host(0); - return; - - } - + schedule_work(&vss_handle_request_work); + return; } icmsghdrp->icflags = ICMSGHDRFLAG_TRANSACTION @@ -358,6 +353,6 @@ void hv_vss_deinit(void) { vss_transaction.state = HVUTIL_DEVICE_DYING; cancel_delayed_work_sync(&vss_timeout_work); - cancel_work_sync(&vss_send_op_work); + cancel_work_sync(&vss_handle_request_work); hvutil_transport_destroy(hvt); } -- 1.7.4.1