From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Reply-To: pmorel@linux.ibm.com Subject: Re: [PATCH 08/10] virtio/s390: add indirection to indicators access References: <20190426183245.37939-1-pasic@linux.ibm.com> <20190426183245.37939-9-pasic@linux.ibm.com> From: Pierre Morel Date: Wed, 8 May 2019 16:31:35 +0200 MIME-Version: 1.0 In-Reply-To: <20190426183245.37939-9-pasic@linux.ibm.com> Content-Type: text/plain; charset="utf-8"; format="flowed" Content-Language: en-US Content-Transfer-Encoding: 8bit Message-Id: <716d47ca-016f-e8f4-6d78-7746a7d9f6ba@linux.ibm.com> Sender: kvm-owner@vger.kernel.org List-Archive: List-Post: To: Halil Pasic , kvm@vger.kernel.org, linux-s390@vger.kernel.org, Cornelia Huck , Martin Schwidefsky , Sebastian Ott Cc: virtualization@lists.linux-foundation.org, "Michael S. Tsirkin" , Christoph Hellwig , Thomas Huth , Christian Borntraeger , Viktor Mihajlovski , Vasily Gorbik , Janosch Frank , Claudio Imbrenda , Farhan Ali , Eric Farman List-ID: On 26/04/2019 20:32, Halil Pasic wrote: > This will come in handy soon when we pull out the indicators from > virtio_ccw_device to a memory area that is shared with the hypervisor > (in particular for protected virtualization guests). > > Signed-off-by: Halil Pasic > --- > drivers/s390/virtio/virtio_ccw.c | 40 +++++++++++++++++++++++++--------------- > 1 file changed, 25 insertions(+), 15 deletions(-) > > diff --git a/drivers/s390/virtio/virtio_ccw.c b/drivers/s390/virtio/virtio_ccw.c > index bb7a92316fc8..1f3e7d56924f 100644 > --- a/drivers/s390/virtio/virtio_ccw.c > +++ b/drivers/s390/virtio/virtio_ccw.c > @@ -68,6 +68,16 @@ struct virtio_ccw_device { > void *airq_info; > }; > > +static inline unsigned long *indicators(struct virtio_ccw_device *vcdev) > +{ > + return &vcdev->indicators; > +} > + > +static inline unsigned long *indicators2(struct virtio_ccw_device *vcdev) > +{ > + return &vcdev->indicators2; > +} > + > struct vq_info_block_legacy { > __u64 queue; > __u32 align; > @@ -337,17 +347,17 @@ static void virtio_ccw_drop_indicator(struct virtio_ccw_device *vcdev, > ccw->cda = (__u32)(unsigned long) thinint_area; > } else { > /* payload is the address of the indicators */ > - indicatorp = kmalloc(sizeof(&vcdev->indicators), > + indicatorp = kmalloc(sizeof(indicators(vcdev)), > GFP_DMA | GFP_KERNEL); > if (!indicatorp) > return; > *indicatorp = 0; > ccw->cmd_code = CCW_CMD_SET_IND; > - ccw->count = sizeof(&vcdev->indicators); > + ccw->count = sizeof(indicators(vcdev)); This looks strange to me. Was already weird before. Lucky we are indicators are long... may be just sizeof(long) > ccw->cda = (__u32)(unsigned long) indicatorp; > } > /* Deregister indicators from host. */ > - vcdev->indicators = 0; > + *indicators(vcdev) = 0; > ccw->flags = 0; > ret = ccw_io_helper(vcdev, ccw, > vcdev->is_thinint ? > @@ -656,10 +666,10 @@ static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs, > * We need a data area under 2G to communicate. Our payload is > * the address of the indicators. > */ > - indicatorp = kmalloc(sizeof(&vcdev->indicators), GFP_DMA | GFP_KERNEL); > + indicatorp = kmalloc(sizeof(indicators(vcdev)), GFP_DMA | GFP_KERNEL); > if (!indicatorp) > goto out; > - *indicatorp = (unsigned long) &vcdev->indicators; > + *indicatorp = (unsigned long) indicators(vcdev); > if (vcdev->is_thinint) { > ret = virtio_ccw_register_adapter_ind(vcdev, vqs, nvqs, ccw); > if (ret) > @@ -668,21 +678,21 @@ static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs, > } > if (!vcdev->is_thinint) { > /* Register queue indicators with host. */ > - vcdev->indicators = 0; > + *indicators(vcdev) = 0; > ccw->cmd_code = CCW_CMD_SET_IND; > ccw->flags = 0; > - ccw->count = sizeof(&vcdev->indicators); > + ccw->count = sizeof(indicators(vcdev)); same as before > ccw->cda = (__u32)(unsigned long) indicatorp; > ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND); > if (ret) > goto out; > } > /* Register indicators2 with host for config changes */ > - *indicatorp = (unsigned long) &vcdev->indicators2; > - vcdev->indicators2 = 0; > + *indicatorp = (unsigned long) indicators2(vcdev); > + *indicators2(vcdev) = 0; > ccw->cmd_code = CCW_CMD_SET_CONF_IND; > ccw->flags = 0; > - ccw->count = sizeof(&vcdev->indicators2); > + ccw->count = sizeof(indicators2(vcdev)); here too > ccw->cda = (__u32)(unsigned long) indicatorp; > ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_CONF_IND); > if (ret) > @@ -1092,17 +1102,17 @@ static void virtio_ccw_int_handler(struct ccw_device *cdev, > vcdev->err = -EIO; > } > virtio_ccw_check_activity(vcdev, activity); > - for_each_set_bit(i, &vcdev->indicators, > - sizeof(vcdev->indicators) * BITS_PER_BYTE) { > + for_each_set_bit(i, indicators(vcdev), > + sizeof(*indicators(vcdev)) * BITS_PER_BYTE) { > /* The bit clear must happen before the vring kick. */ > - clear_bit(i, &vcdev->indicators); > + clear_bit(i, indicators(vcdev)); > barrier(); > vq = virtio_ccw_vq_by_ind(vcdev, i); > vring_interrupt(0, vq); > } > - if (test_bit(0, &vcdev->indicators2)) { > + if (test_bit(0, indicators2(vcdev))) { > virtio_config_changed(&vcdev->vdev); > - clear_bit(0, &vcdev->indicators2); > + clear_bit(0, indicators2(vcdev)); > } > } > > Here again just a fast check. I will go in the functional later. Regards, Pierre -- Pierre Morel Linux/KVM/QEMU in Böblingen - Germany