From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1LUSKC-0005qR-MZ for qemu-devel@nongnu.org; Tue, 03 Feb 2009 15:56:52 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1LUSKB-0005ps-Rh for qemu-devel@nongnu.org; Tue, 03 Feb 2009 15:56:52 -0500 Received: from [199.232.76.173] (port=43800 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1LUSKB-0005pl-Hh for qemu-devel@nongnu.org; Tue, 03 Feb 2009 15:56:51 -0500 Received: from mail-qy0-f20.google.com ([209.85.221.20]:57083) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1LUSKB-000534-4N for qemu-devel@nongnu.org; Tue, 03 Feb 2009 15:56:51 -0500 Received: by qyk13 with SMTP id 13so4222630qyk.10 for ; Tue, 03 Feb 2009 12:56:48 -0800 (PST) Message-ID: <4988AF7C.50103@codemonkey.ws> Date: Tue, 03 Feb 2009 14:56:28 -0600 From: Anthony Liguori MIME-Version: 1.0 References: <20090203192932.19598.50925.stgit@kvm.aw> <20090203192953.19598.41310.stgit@kvm.aw> In-Reply-To: <20090203192953.19598.41310.stgit@kvm.aw> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Subject: [Qemu-devel] Re: [PATCH v2 4/8] qemu:virtio-net: Add a virtqueue for control commands from the guest Reply-To: qemu-devel@nongnu.org List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Alex Williamson Cc: markmc@redhat.com, qemu-devel@nongnu.org, kvm@vger.kernel.org Alex Williamson wrote: > This will be used for RX mode, MAC table, VLAN table control, etc... > > The control transaction consists of one or more "out" sg entries and > one or more "in" sg entries. The first out entry contains a header > defining the class and command. Additional out entries may provide > data for the command. A response via the ack entry is required > and the guest will typically be waiting for it. > > Signed-off-by: Alex Williamson > --- > > hw/virtio-net.c | 33 ++++++++++++++++++++++++++++++++- > hw/virtio-net.h | 18 ++++++++++++++++++ > 2 files changed, 50 insertions(+), 1 deletions(-) > > diff --git a/hw/virtio-net.c b/hw/virtio-net.c > index 073f23a..3378cc2 100644 > --- a/hw/virtio-net.c > +++ b/hw/virtio-net.c > @@ -25,6 +25,7 @@ typedef struct VirtIONet > uint16_t status; > VirtQueue *rx_vq; > VirtQueue *tx_vq; > + VirtQueue *ctrl_vq; > VLANClientState *vc; > QEMUTimer *tx_timer; > int tx_timer_active; > @@ -79,7 +80,9 @@ static void virtio_net_set_link_status(VLANClientState *vc) > > static uint32_t virtio_net_get_features(VirtIODevice *vdev) > { > - uint32_t features = (1 << VIRTIO_NET_F_MAC) | (1 << VIRTIO_NET_F_STATUS); > + uint32_t features = (1 << VIRTIO_NET_F_MAC) | > + (1 << VIRTIO_NET_F_STATUS) | > + (1 << VIRTIO_NET_F_CTRL_VQ); > > return features; > } > @@ -91,6 +94,33 @@ static void virtio_net_set_features(VirtIODevice *vdev, uint32_t features) > n->mergeable_rx_bufs = !!(features & (1 << VIRTIO_NET_F_MRG_RXBUF)); > } > > +static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq) > +{ > + struct virtio_net_ctrl_hdr *ctrl; > + virtio_net_ctrl_ack *status; > + VirtQueueElement elem; > + > + while (virtqueue_pop(vq, &elem)) { > + if ((elem.in_num < 1) | (elem.out_num < 1)) { > + fprintf(stderr, "virtio-net ctrl missing headers\n"); > + exit(1); > + } > + > + if (elem.out_sg[0].iov_len < sizeof(*ctrl) || > + elem.out_sg[elem.in_num - 1].iov_len < sizeof(*status)) { > + fprintf(stderr, "virtio-net ctrl header not in correct element\n"); > + exit(1); > + } > + > + ctrl = elem.out_sg[0].iov_base; > + status = elem.in_sg[elem.in_num - 1].iov_base; > This works only because we're dealing with uint8_ts but it's broken elsewhere in virtio-net. iov_base is guest memory which means it may have different endianness. We really should be using ldub_p() here. > + *status = VIRTIO_NET_ERR; > And stb_p() here. Regards, Anthony Liguori > + virtqueue_push(vq, &elem, sizeof(*status)); > + virtio_notify(vdev, vq); > + } > +} > + > /* RX */ > > static void virtio_net_handle_rx(VirtIODevice *vdev, VirtQueue *vq) > @@ -356,6 +386,7 @@ void virtio_net_init(PCIBus *bus, NICInfo *nd, int devfn) > n->vdev.set_features = virtio_net_set_features; > n->rx_vq = virtio_add_queue(&n->vdev, 256, virtio_net_handle_rx); > n->tx_vq = virtio_add_queue(&n->vdev, 256, virtio_net_handle_tx); > + n->ctrl_vq = virtio_add_queue(&n->vdev, 16, virtio_net_handle_ctrl); > memcpy(n->mac, nd->macaddr, ETH_ALEN); > n->status = VIRTIO_NET_S_LINK_UP; > n->vc = qemu_new_vlan_client(nd->vlan, nd->model, nd->name, > diff --git a/hw/virtio-net.h b/hw/virtio-net.h > index 9dce663..119e38d 100644 > --- a/hw/virtio-net.h > +++ b/hw/virtio-net.h > @@ -40,6 +40,7 @@ > #define VIRTIO_NET_F_HOST_UFO 14 /* Host can handle UFO in. */ > #define VIRTIO_NET_F_MRG_RXBUF 15 /* Host can merge receive buffers. */ > #define VIRTIO_NET_F_STATUS 16 /* virtio_net_config.status available */ > +#define VIRTIO_NET_F_CTRL_VQ 17 /* Control channel available */ > > #define VIRTIO_NET_S_LINK_UP 1 /* Link is up */ > > @@ -84,4 +85,21 @@ struct virtio_net_hdr_mrg_rxbuf > > void virtio_net_init(PCIBus *bus, NICInfo *nd, int devfn); > > +/* > + * Control virtqueue data structures > + * > + * The control virtqueue expects a header in the first sg entry > + * and an ack/status response in the last entry. Data for the > + * command goes in between. > + */ > +struct virtio_net_ctrl_hdr { > + uint8_t class; > + uint8_t cmd; > +}; > + > +typedef uint8_t virtio_net_ctrl_ack; > + > +#define VIRTIO_NET_OK 0 > +#define VIRTIO_NET_ERR 1 > + > #endif > >