From patchwork Sat Mar 9 07:52:15 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: 2241251 X-Patchwork-Delegate: bhelgaas@google.com Return-Path: X-Original-To: patchwork-linux-pci@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork2.kernel.org (Postfix) with ESMTP id 8102DDFE75 for ; Sat, 9 Mar 2013 07:52:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932428Ab3CIHwb (ORCPT ); Sat, 9 Mar 2013 02:52:31 -0500 Received: from g4t0014.houston.hp.com ([15.201.24.17]:41649 "EHLO g4t0014.houston.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932209Ab3CIHw3 (ORCPT ); Sat, 9 Mar 2013 02:52:29 -0500 Received: from g4t0009.houston.hp.com (g4t0009.houston.hp.com [16.234.32.26]) by g4t0014.houston.hp.com (Postfix) with ESMTP id 0674924166; Sat, 9 Mar 2013 07:52:29 +0000 (UTC) Received: from cumin.cce.hp.com (cumin.cce.hp.com [15.250.252.195]) by g4t0009.houston.hp.com (Postfix) with ESMTP id C3FA6C0D5; Sat, 9 Mar 2013 07:52:28 +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 v7 1/3] VFIO: Wrapper for getting reference to vfio_device from device Date: Sat, 9 Mar 2013 01:52:15 -0600 Message-Id: <1362815537-27303-2-git-send-email-vijaymohan.pandarathil@hp.com> X-Mailer: git-send-email 1.7.11.3 In-Reply-To: <1362815537-27303-1-git-send-email-vijaymohan.pandarathil@hp.com> References: <1362815537-27303-1-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 | 30 +++++++++++++++++++++++++++++- include/linux/vfio.h | 3 +++ 2 files changed, 32 insertions(+), 1 deletion(-) diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c index fcc12f3..21eddd9 100644 --- a/drivers/vfio/vfio.c +++ b/drivers/vfio/vfio.c @@ -392,12 +392,13 @@ 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) { @@ -627,6 +628,33 @@ int vfio_add_group_dev(struct device *dev, } EXPORT_SYMBOL_GPL(vfio_add_group_dev); +/** + * Get a reference to the vfio_device for a device that is known to + * be bound to a vfio driver. The driver implicitly holds a + * vfio_device reference between vfio_add_group_dev and + * vfio_del_group_dev. We can therefore use drvdata to increment + * that reference from the struct device. This additional + * reference must be released by calling vfio_device_put. + */ +struct vfio_device *vfio_device_get_from_dev(struct device *dev) +{ + struct vfio_device *device = dev_get_drvdata(dev); + + vfio_device_get(device); + + 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); + /* Given a referenced group, check if it contains the device */ static bool vfio_dev_present(struct vfio_group *group, struct device *dev) { 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