Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756052AbaJWQVe (ORCPT ); Thu, 23 Oct 2014 12:21:34 -0400 Received: from mx1.redhat.com ([209.132.183.28]:54887 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756159AbaJWQV0 (ORCPT ); Thu, 23 Oct 2014 12:21:26 -0400 Date: Thu, 23 Oct 2014 19:24:53 +0300 From: "Michael S. Tsirkin" To: linux-kernel@vger.kernel.org Cc: Thomas Huth , David Hildenbrand , Cornelia Huck , Christian Borntraeger , linux390@de.ibm.com, Martin Schwidefsky , Heiko Carstens , linux-s390@vger.kernel.org Subject: [PATCH RFC v4 14/17] KVM: s390: Set virtio-ccw transport revision Message-ID: <1414081380-14623-15-git-send-email-mst@redhat.com> References: <1414081380-14623-1-git-send-email-mst@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1414081380-14623-1-git-send-email-mst@redhat.com> X-Mutt-Fcc: =sent Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Thomas Huth With the new SET-VIRTIO-REVISION command of the virtio 1.0 standard, we can now negotiate the virtio-ccw revision after setting a channel online. Note that we don't negotiate version 1 yet. [Cornelia Huck: reworked revision loop a bit] Reviewed-by: David Hildenbrand Signed-off-by: Thomas Huth Signed-off-by: Cornelia Huck Signed-off-by: Michael S. Tsirkin --- drivers/s390/kvm/virtio_ccw.c | 63 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 63 insertions(+) diff --git a/drivers/s390/kvm/virtio_ccw.c b/drivers/s390/kvm/virtio_ccw.c index 27aab69..394ddb8 100644 --- a/drivers/s390/kvm/virtio_ccw.c +++ b/drivers/s390/kvm/virtio_ccw.c @@ -55,6 +55,7 @@ struct virtio_ccw_device { struct ccw_device *cdev; __u32 curr_io; int err; + unsigned int revision; /* Transport revision */ wait_queue_head_t wait_q; spinlock_t lock; struct list_head virtqueues; @@ -86,6 +87,15 @@ struct virtio_thinint_area { u8 isc; } __packed; +struct virtio_rev_info { + __u16 revision; + __u16 length; + __u8 data[]; +}; + +/* the highest virtio-ccw revision we support */ +#define VIRTIO_CCW_REV_MAX 0 + struct virtio_ccw_vq_info { struct virtqueue *vq; int num; @@ -122,6 +132,7 @@ static struct airq_info *airq_areas[MAX_AIRQ_AREAS]; #define CCW_CMD_WRITE_STATUS 0x31 #define CCW_CMD_READ_VQ_CONF 0x32 #define CCW_CMD_SET_IND_ADAPTER 0x73 +#define CCW_CMD_SET_VIRTIO_REV 0x83 #define VIRTIO_CCW_DOING_SET_VQ 0x00010000 #define VIRTIO_CCW_DOING_RESET 0x00040000 @@ -134,6 +145,7 @@ static struct airq_info *airq_areas[MAX_AIRQ_AREAS]; #define VIRTIO_CCW_DOING_READ_VQ_CONF 0x02000000 #define VIRTIO_CCW_DOING_SET_CONF_IND 0x04000000 #define VIRTIO_CCW_DOING_SET_IND_ADAPTER 0x08000000 +#define VIRTIO_CCW_DOING_SET_VIRTIO_REV 0x10000000 #define VIRTIO_CCW_INTPARM_MASK 0xffff0000 static struct virtio_ccw_device *to_vc_device(struct virtio_device *vdev) @@ -934,6 +946,7 @@ static void virtio_ccw_int_handler(struct ccw_device *cdev, case VIRTIO_CCW_DOING_RESET: case VIRTIO_CCW_DOING_READ_VQ_CONF: case VIRTIO_CCW_DOING_SET_IND_ADAPTER: + case VIRTIO_CCW_DOING_SET_VIRTIO_REV: vcdev->curr_io &= ~activity; wake_up(&vcdev->wait_q); break; @@ -1049,6 +1062,51 @@ static int virtio_ccw_offline(struct ccw_device *cdev) return 0; } +static int virtio_ccw_set_transport_rev(struct virtio_ccw_device *vcdev) +{ + struct virtio_rev_info *rev; + struct ccw1 *ccw; + int ret; + + ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL); + if (!ccw) + return -ENOMEM; + rev = kzalloc(sizeof(*rev), GFP_DMA | GFP_KERNEL); + if (!rev) { + kfree(ccw); + return -ENOMEM; + } + + /* Set transport revision */ + ccw->cmd_code = CCW_CMD_SET_VIRTIO_REV; + ccw->flags = 0; + ccw->count = sizeof(*rev); + ccw->cda = (__u32)(unsigned long)rev; + + vcdev->revision = VIRTIO_CCW_REV_MAX; + do { + rev->revision = vcdev->revision; + /* none of our supported revisions carry payload */ + rev->length = 0; + ret = ccw_io_helper(vcdev, ccw, + VIRTIO_CCW_DOING_SET_VIRTIO_REV); + if (ret == -EOPNOTSUPP) { + if (vcdev->revision == 0) + /* + * The host device does not support setting + * the revision: let's operate it in legacy + * mode. + */ + ret = 0; + else + vcdev->revision--; + } + } while (ret == -EOPNOTSUPP); + + kfree(ccw); + kfree(rev); + return ret; +} static int virtio_ccw_online(struct ccw_device *cdev) { @@ -1089,6 +1147,11 @@ static int virtio_ccw_online(struct ccw_device *cdev) spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags); vcdev->vdev.id.vendor = cdev->id.cu_type; vcdev->vdev.id.device = cdev->id.cu_model; + + ret = virtio_ccw_set_transport_rev(vcdev); + if (ret) + goto out_free; + ret = register_virtio_device(&vcdev->vdev); if (ret) { dev_warn(&cdev->dev, "Failed to register virtio device: %d\n", -- MST -- 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/