From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754624AbcLaJKu (ORCPT ); Sat, 31 Dec 2016 04:10:50 -0500 Received: from cn.fujitsu.com ([59.151.112.132]:28236 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1752580AbcLaJKr (ORCPT ); Sat, 31 Dec 2016 04:10:47 -0500 X-IronPort-AV: E=Sophos;i="5.22,518,1449504000"; d="scan'208";a="14388154" From: Cao jin To: , , CC: , , Subject: [PATCH v2] vfio/pci: Support error recovery Date: Sat, 31 Dec 2016 17:15:36 +0800 Message-ID: <1483175736-17137-1-git-send-email-caoj.fnst@cn.fujitsu.com> X-Mailer: git-send-email 2.1.0 MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.167.226.69] X-yoursite-MailScanner-ID: 3330B477B1FE.AAF91 X-yoursite-MailScanner: Found to be clean X-yoursite-MailScanner-From: caoj.fnst@cn.fujitsu.com Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Support serious device error recovery Signed-off-by: Cao jin --- drivers/vfio/pci/vfio_pci.c | 70 +++++++++++++++++++++++++++++++++++-- drivers/vfio/pci/vfio_pci_private.h | 2 ++ 2 files changed, 70 insertions(+), 2 deletions(-) diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c index 712a849..752af20 100644 --- a/drivers/vfio/pci/vfio_pci.c +++ b/drivers/vfio/pci/vfio_pci.c @@ -534,6 +534,15 @@ static long vfio_pci_ioctl(void *device_data, { struct vfio_pci_device *vdev = device_data; unsigned long minsz; + int ret; + + if (vdev->aer_recovering && (cmd == VFIO_DEVICE_SET_IRQS || + cmd == VFIO_DEVICE_RESET || cmd == VFIO_DEVICE_PCI_HOT_RESET)) { + ret = wait_for_completion_interruptible( + &vdev->aer_completion); + if (ret) + return ret; + } if (cmd == VFIO_DEVICE_GET_INFO) { struct vfio_device_info info; @@ -953,6 +962,15 @@ static ssize_t vfio_pci_rw(void *device_data, char __user *buf, { unsigned int index = VFIO_PCI_OFFSET_TO_INDEX(*ppos); struct vfio_pci_device *vdev = device_data; + int ret; + + /* block all kinds of access during host recovery */ + if (vdev->aer_recovering) { + ret = wait_for_completion_interruptible( + &vdev->aer_completion); + if (ret) + return ret; + } if (index >= VFIO_PCI_NUM_REGIONS + vdev->num_regions) return -EINVAL; @@ -1117,6 +1135,7 @@ static int vfio_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) vdev->irq_type = VFIO_PCI_NUM_IRQS; mutex_init(&vdev->igate); spin_lock_init(&vdev->irqlock); + init_completion(&vdev->aer_completion); ret = vfio_add_group_dev(&pdev->dev, &vfio_pci_ops, vdev); if (ret) { @@ -1176,6 +1195,9 @@ static pci_ers_result_t vfio_pci_aer_err_detected(struct pci_dev *pdev, { struct vfio_pci_device *vdev; struct vfio_device *device; + u32 uncor_status; + unsigned int aer_cap_offset; + int ret; device = vfio_device_get_from_dev(&pdev->dev); if (device == NULL) @@ -1187,10 +1209,29 @@ static pci_ers_result_t vfio_pci_aer_err_detected(struct pci_dev *pdev, return PCI_ERS_RESULT_DISCONNECT; } + /* + * get device's uncorrectable error status as soon as possible, + * and signal it to user space. The later we read it, the possibility + * the register value is mangled grows. + */ + aer_cap_offset = pci_find_ext_capability(vdev->pdev, PCI_EXT_CAP_ID_ERR); + ret = pci_read_config_dword(vdev->pdev, aer_cap_offset + + PCI_ERR_UNCOR_STATUS, &uncor_status); + if (ret) + return PCI_ERS_RESULT_DISCONNECT; + + pr_info("device %d got AER detect notification. uncorrectable error status = 0x%x\n", pdev->devfn, uncor_status);//to be removed mutex_lock(&vdev->igate); - if (vdev->err_trigger) - eventfd_signal(vdev->err_trigger, 1); + vdev->aer_recovering = true; + reinit_completion(&vdev->aer_completion); + + if (vdev->err_trigger && uncor_status) { + pr_info("device %d signal uncor status 0x%x to user", + pdev->devfn, uncor_status); + /* signal uncorrectable error status to user space */ + eventfd_signal(vdev->err_trigger, uncor_status); + } mutex_unlock(&vdev->igate); @@ -1199,8 +1240,33 @@ static pci_ers_result_t vfio_pci_aer_err_detected(struct pci_dev *pdev, return PCI_ERS_RESULT_CAN_RECOVER; } +static void vfio_pci_aer_resume(struct pci_dev *pdev) +{ + struct vfio_pci_device *vdev; + struct vfio_device *device; + + device = vfio_device_get_from_dev(&pdev->dev); + if (device == NULL) + return; + + vdev = vfio_device_data(device); + if (vdev == NULL) { + vfio_device_put(device); + return; + } + + mutex_lock(&vdev->igate); + vdev->aer_recovering = false; + mutex_unlock(&vdev->igate); + + complete_all(&vdev->aer_completion); + + vfio_device_put(device); +} + static const struct pci_error_handlers vfio_err_handlers = { .error_detected = vfio_pci_aer_err_detected, + .resume = vfio_pci_aer_resume, }; static struct pci_driver vfio_pci_driver = { diff --git a/drivers/vfio/pci/vfio_pci_private.h b/drivers/vfio/pci/vfio_pci_private.h index 8a7d546..ba8471f 100644 --- a/drivers/vfio/pci/vfio_pci_private.h +++ b/drivers/vfio/pci/vfio_pci_private.h @@ -83,6 +83,8 @@ struct vfio_pci_device { bool bardirty; bool has_vga; bool needs_reset; + bool aer_recovering; + struct completion aer_completion; struct pci_saved_state *pci_saved_state; int refcnt; struct eventfd_ctx *err_trigger; -- 1.8.3.1