From patchwork Thu Feb 14 10:41:53 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Pandarathil, Vijaymohan R" X-Patchwork-Id: 2141201 X-Patchwork-Delegate: bhelgaas@google.com Return-Path: X-Original-To: patchwork-linux-pci@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork1.kernel.org (Postfix) with ESMTP id EC7333FCF6 for ; Thu, 14 Feb 2013 10:43:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933839Ab3BNKnN (ORCPT ); Thu, 14 Feb 2013 05:43:13 -0500 Received: from g5t0009.atlanta.hp.com ([15.192.0.46]:9392 "EHLO g5t0009.atlanta.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933606Ab3BNKnM (ORCPT ); Thu, 14 Feb 2013 05:43:12 -0500 Received: from g4t0018.houston.hp.com (g4t0018.houston.hp.com [16.234.32.27]) by g5t0009.atlanta.hp.com (Postfix) with ESMTP id 306983075D; Thu, 14 Feb 2013 10:43:12 +0000 (UTC) Received: from cumin.cce.hp.com (cumin.cce.hp.com [15.250.252.195]) by g4t0018.houston.hp.com (Postfix) with ESMTP id D8355102BF; Thu, 14 Feb 2013 10:42:11 +0000 (UTC) From: Vijay Mohan Pandarathil To: alex.williamson@redhat.com, gleb@redhat.com, bhelgaas@google.com, blauwirbel@gmail.com, lance.oritz@hp.com, kvm@vger.kernel.org, qemu-devel@nongnu.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Vijay Mohan Pandarathil Subject: [PATCH v4 1/3] VFIO: Wrapper for getting reference to vfio_device from device Date: Thu, 14 Feb 2013 04:41:53 -0600 Message-Id: <1360838515-17558-2-git-send-email-vijaymohan.pandarathil@hp.com> X-Mailer: git-send-email 1.7.11.3 In-Reply-To: <1360838515-17558-1-git-send-email-vijaymohan.pandarathil@hp.com> References: <1360838515-17558-1-git-send-email-vijaymohan.pandarathil@hp.com> Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org - Added vfio_device_get_from_dev() as wrapper to get reference to vfio_device from struct device. - Added vfio_device_data() as a wrapper to get device_data from vfio_device. Signed-off-by: Vijay Mohan Pandarathil --- drivers/vfio/vfio.c | 47 ++++++++++++++++++++++++++++++++++------------- include/linux/vfio.h | 3 +++ 2 files changed, 37 insertions(+), 13 deletions(-) diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c index 12c264d..863d1d3 100644 --- a/drivers/vfio/vfio.c +++ b/drivers/vfio/vfio.c @@ -407,12 +407,13 @@ static void vfio_device_release(struct kref *kref) } /* Device reference always implies a group reference */ -static void vfio_device_put(struct vfio_device *device) +void vfio_device_put(struct vfio_device *device) { struct vfio_group *group = device->group; kref_put_mutex(&device->kref, vfio_device_release, &group->device_lock); vfio_group_put(group); } +EXPORT_SYMBOL_GPL(vfio_device_put); static void vfio_device_get(struct vfio_device *device) { @@ -642,8 +643,12 @@ int vfio_add_group_dev(struct device *dev, } EXPORT_SYMBOL_GPL(vfio_add_group_dev); -/* Test whether a struct device is present in our tracking */ -static bool vfio_dev_present(struct device *dev) +/** + * This does a get on the vfio_device from device. + * Callers of this function will have to call vfio_put_device() to + * remove the reference. + */ +struct vfio_device *vfio_device_get_from_dev(struct device *dev) { struct iommu_group *iommu_group; struct vfio_group *group; @@ -651,25 +656,41 @@ static bool vfio_dev_present(struct device *dev) iommu_group = iommu_group_get(dev); if (!iommu_group) - return false; + return NULL; group = vfio_group_get_from_iommu(iommu_group); if (!group) { iommu_group_put(iommu_group); - return false; + return NULL; } device = vfio_group_get_device(group, dev); - if (!device) { - vfio_group_put(group); - iommu_group_put(iommu_group); - return false; - } - - vfio_device_put(device); vfio_group_put(group); iommu_group_put(iommu_group); - return true; + return device; +} +EXPORT_SYMBOL_GPL(vfio_device_get_from_dev); + +/* + * Caller must hold a reference to the vfio_device + */ +void *vfio_device_data(struct vfio_device *device) +{ + return device->device_data; +} +EXPORT_SYMBOL_GPL(vfio_device_data); + +/* Test whether a struct device is present in our tracking */ +static bool vfio_dev_present(struct device *dev) +{ + struct vfio_device *device; + + device = vfio_device_get_from_dev(dev); + if (device) { + vfio_device_put(device); + return true; + } else + return false; } /* diff --git a/include/linux/vfio.h b/include/linux/vfio.h index ab9e862..ac8d488 100644 --- a/include/linux/vfio.h +++ b/include/linux/vfio.h @@ -45,6 +45,9 @@ extern int vfio_add_group_dev(struct device *dev, void *device_data); extern void *vfio_del_group_dev(struct device *dev); +extern struct vfio_device *vfio_device_get_from_dev(struct device *dev); +extern void vfio_device_put(struct vfio_device *device); +extern void *vfio_device_data(struct vfio_device *device); /** * struct vfio_iommu_driver_ops - VFIO IOMMU driver callbacks