Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754892AbbEMSdX (ORCPT ); Wed, 13 May 2015 14:33:23 -0400 Received: from mx1.redhat.com ([209.132.183.28]:52972 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753531AbbEMSdU (ORCPT ); Wed, 13 May 2015 14:33:20 -0400 Message-ID: <1431541959.3625.54.camel@redhat.com> Subject: Re: [PATCH 3/5] VFIO: platform: add reset callback From: Alex Williamson To: Eric Auger Cc: eric.auger@st.com, christoffer.dall@linaro.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, b.reynal@virtualopensystems.com, linux-kernel@vger.kernel.org, patches@linaro.org, agraf@suse.de, Bharat.Bhushan@freescale.com Date: Wed, 13 May 2015 12:32:39 -0600 In-Reply-To: <1431008843-28411-4-git-send-email-eric.auger@linaro.org> References: <1431008843-28411-1-git-send-email-eric.auger@linaro.org> <1431008843-28411-4-git-send-email-eric.auger@linaro.org> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2932 Lines: 84 On Thu, 2015-05-07 at 16:27 +0200, Eric Auger wrote: > A new reset callback is introduced. If this callback is populated, > the reset is invoked on device release or upon userspace ioctl. The > modality is exposed on VFIO_DEVICE_GET_INFO. > > Signed-off-by: Eric Auger > > --- > > v2 -> v3: > - change patch title and commit message. Use IS_ERR_OR_NULL to > anticipate for getter returned value. > > v1 -> v2: > - On VFIO_DEVICE_RESET returns -EINVAL in case the callback is not > populated (instead of -ENOTTY) > --- > drivers/vfio/platform/vfio_platform_common.c | 12 ++++++++++-- > drivers/vfio/platform/vfio_platform_private.h | 1 + > 2 files changed, 11 insertions(+), 2 deletions(-) > > diff --git a/drivers/vfio/platform/vfio_platform_common.c b/drivers/vfio/platform/vfio_platform_common.c > index edbf24c..0d10018 100644 > --- a/drivers/vfio/platform/vfio_platform_common.c > +++ b/drivers/vfio/platform/vfio_platform_common.c > @@ -103,6 +103,8 @@ static void vfio_platform_release(void *device_data) > mutex_lock(&driver_lock); > > if (!(--vdev->refcnt)) { > + if (!IS_ERR_OR_NULL(vdev->reset)) > + vdev->reset(vdev); It seems sloppy to have a function pointer that could be ERR_PTR. Should we also be trying to reset on device open? > vfio_platform_regions_cleanup(vdev); > vfio_platform_irq_cleanup(vdev); > } > @@ -162,6 +164,8 @@ static long vfio_platform_ioctl(void *device_data, > if (info.argsz < minsz) > return -EINVAL; > > + if (!IS_ERR_OR_NULL(vdev->reset)) > + vdev->flags |= VFIO_DEVICE_FLAGS_RESET; > info.flags = vdev->flags; > info.num_regions = vdev->num_regions; > info.num_irqs = vdev->num_irqs; > @@ -255,8 +259,12 @@ static long vfio_platform_ioctl(void *device_data, > > return ret; > > - } else if (cmd == VFIO_DEVICE_RESET) > - return -EINVAL; > + } else if (cmd == VFIO_DEVICE_RESET) { > + if (!IS_ERR_OR_NULL(vdev->reset)) > + return vdev->reset(vdev); > + else > + return -EINVAL; > + } > > return -ENOTTY; > } > diff --git a/drivers/vfio/platform/vfio_platform_private.h b/drivers/vfio/platform/vfio_platform_private.h > index 68909a4..84ccf6d 100644 > --- a/drivers/vfio/platform/vfio_platform_private.h > +++ b/drivers/vfio/platform/vfio_platform_private.h > @@ -68,6 +68,7 @@ struct vfio_platform_device { > (*get_resource)(struct vfio_platform_device *vdev, int i); > int (*get_irq)(struct vfio_platform_device *vdev, int i); > struct device *(*get_device)(struct vfio_platform_device *vdev); > + int (*reset)(struct vfio_platform_device *vdev); > }; > > typedef int (*vfio_platform_reset_fn_t)(struct vfio_platform_device *vdev); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/