From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C325FC4360C for ; Thu, 26 Sep 2019 16:30:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 96D7C21655 for ; Thu, 26 Sep 2019 16:30:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727478AbfIZQay (ORCPT ); Thu, 26 Sep 2019 12:30:54 -0400 Received: from foss.arm.com ([217.140.110.172]:54406 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727388AbfIZQay (ORCPT ); Thu, 26 Sep 2019 12:30:54 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 70CAA28; Thu, 26 Sep 2019 09:30:53 -0700 (PDT) Received: from e121166-lin.cambridge.arm.com (unknown [10.1.196.255]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 1BF313F534; Thu, 26 Sep 2019 09:30:52 -0700 (PDT) Date: Thu, 26 Sep 2019 17:30:49 +0100 From: Lorenzo Pieralisi To: Dexuan Cui Cc: KY Srinivasan , Haiyang Zhang , Stephen Hemminger , "sashal@kernel.org" , "bhelgaas@google.com" , "linux-hyperv@vger.kernel.org" , "linux-pci@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Michael Kelley Subject: Re: [PATCH 2/4] PCI: hv: Add the support of hibernation Message-ID: <20190926163049.GB7827@e121166-lin.cambridge.arm.com> References: <1568245086-70601-1-git-send-email-decui@microsoft.com> <1568245086-70601-3-git-send-email-decui@microsoft.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1568245086-70601-3-git-send-email-decui@microsoft.com> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-hyperv-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-hyperv@vger.kernel.org On Wed, Sep 11, 2019 at 11:38:20PM +0000, Dexuan Cui wrote: > Implement the suspend/resume callbacks for hibernation. > > hv_pci_suspend() needs to prevent any new work from being queued: a later > patch will address this issue. I don't see why you have two separate patches, the second one fixing the previous (this one). Squash them together and merge them as such, or there is something I am missing here. Lorenzo > Signed-off-by: Dexuan Cui > --- > drivers/pci/controller/pci-hyperv.c | 76 +++++++++++++++++++++++++++++++++++++ > 1 file changed, 76 insertions(+) > > diff --git a/drivers/pci/controller/pci-hyperv.c b/drivers/pci/controller/pci-hyperv.c > index 03fa039..3b77a3a 100644 > --- a/drivers/pci/controller/pci-hyperv.c > +++ b/drivers/pci/controller/pci-hyperv.c > @@ -1398,6 +1398,23 @@ static void prepopulate_bars(struct hv_pcibus_device *hbus) > > spin_lock_irqsave(&hbus->device_list_lock, flags); > > + /* > + * Clear the memory enable bit, in case it's already set. This occurs > + * in the suspend path of hibernation, where the device is suspended, > + * resumed and suspended again: see hibernation_snapshot() and > + * hibernation_platform_enter(). > + * > + * If the memory enable bit is already set, Hyper-V sliently ignores > + * the below BAR updates, and the related PCI device driver can not > + * work, because reading from the device register(s) always returns > + * 0xFFFFFFFF. > + */ > + list_for_each_entry(hpdev, &hbus->children, list_entry) { > + _hv_pcifront_read_config(hpdev, PCI_COMMAND, 2, &command); > + command &= ~PCI_COMMAND_MEMORY; > + _hv_pcifront_write_config(hpdev, PCI_COMMAND, 2, command); > + } > + > /* Pick addresses for the BARs. */ > do { > list_for_each_entry(hpdev, &hbus->children, list_entry) { > @@ -2737,6 +2754,63 @@ static int hv_pci_remove(struct hv_device *hdev) > return ret; > } > > +static int hv_pci_suspend(struct hv_device *hdev) > +{ > + struct hv_pcibus_device *hbus = hv_get_drvdata(hdev); > + int ret; > + > + /* XXX: Need to prevent any new work from being queued. */ > + flush_workqueue(hbus->wq); > + > + ret = hv_pci_bus_exit(hdev, true); > + if (ret) > + return ret; > + > + vmbus_close(hdev->channel); > + > + return 0; > +} > + > +static int hv_pci_resume(struct hv_device *hdev) > +{ > + struct hv_pcibus_device *hbus = hv_get_drvdata(hdev); > + enum pci_protocol_version_t version[1]; > + int ret; > + > + hbus->state = hv_pcibus_init; > + > + ret = vmbus_open(hdev->channel, pci_ring_size, pci_ring_size, NULL, 0, > + hv_pci_onchannelcallback, hbus); > + if (ret) > + return ret; > + > + /* Only use the version that was in use before hibernation. */ > + version[0] = pci_protocol_version; > + ret = hv_pci_protocol_negotiation(hdev, version, 1); > + if (ret) > + goto out; > + > + ret = hv_pci_query_relations(hdev); > + if (ret) > + goto out; > + > + ret = hv_pci_enter_d0(hdev); > + if (ret) > + goto out; > + > + ret = hv_send_resources_allocated(hdev); > + if (ret) > + goto out; > + > + prepopulate_bars(hbus); > + > + hbus->state = hv_pcibus_installed; > + return 0; > +out: > + vmbus_close(hdev->channel); > + return ret; > +} > + > static const struct hv_vmbus_device_id hv_pci_id_table[] = { > /* PCI Pass-through Class ID */ > /* 44C4F61D-4444-4400-9D52-802E27EDE19F */ > @@ -2751,6 +2825,8 @@ static int hv_pci_remove(struct hv_device *hdev) > .id_table = hv_pci_id_table, > .probe = hv_pci_probe, > .remove = hv_pci_remove, > + .suspend = hv_pci_suspend, > + .resume = hv_pci_resume, > }; > > static void __exit exit_hv_pci_drv(void) > -- > 1.8.3.1 >