Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763640AbZCaSsd (ORCPT ); Tue, 31 Mar 2009 14:48:33 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754289AbZCaSmA (ORCPT ); Tue, 31 Mar 2009 14:42:00 -0400 Received: from victor.provo.novell.com ([137.65.250.26]:38365 "EHLO victor.provo.novell.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760825AbZCaSlp (ORCPT ); Tue, 31 Mar 2009 14:41:45 -0400 From: Gregory Haskins Subject: [RFC PATCH 12/17] venettap: add scatter-gather support To: linux-kernel@vger.kernel.org Cc: agraf@suse.de, pmullaney@novell.com, pmorreale@novell.com, anthony@codemonkey.ws, rusty@rustcorp.com.au, netdev@vger.kernel.org, kvm@vger.kernel.org Date: Tue, 31 Mar 2009 14:43:50 -0400 Message-ID: <20090331184349.28333.41764.stgit@dev.haskins.net> In-Reply-To: <20090331184057.28333.77287.stgit@dev.haskins.net> References: <20090331184057.28333.77287.stgit@dev.haskins.net> User-Agent: StGIT/0.14.3 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 8391 Lines: 331 Signed-off-by: Gregory Haskins --- drivers/vbus/devices/venet-tap.c | 236 +++++++++++++++++++++++++++++++++++++- 1 files changed, 229 insertions(+), 7 deletions(-) diff --git a/drivers/vbus/devices/venet-tap.c b/drivers/vbus/devices/venet-tap.c index ccce58e..0ccb7ed 100644 --- a/drivers/vbus/devices/venet-tap.c +++ b/drivers/vbus/devices/venet-tap.c @@ -80,6 +80,13 @@ enum { TX_IOQ_CONGESTED, }; +struct venettap; + +struct venettap_rx_ops { + int (*decode)(struct venettap *priv, void *ptr, int len); + int (*import)(struct venettap *, struct sk_buff *, void *, int); +}; + struct venettap { spinlock_t lock; unsigned char hmac[ETH_ALEN]; /* host-mac */ @@ -107,6 +114,12 @@ struct venettap { struct vbus_memctx *ctx; struct venettap_queue rxq; struct venettap_queue txq; + struct venettap_rx_ops *rx_ops; + struct { + struct venet_sg *desc; + size_t len; + int enabled:1; + } sg; int connected:1; int opened:1; int link:1; @@ -288,6 +301,183 @@ venettap_change_mtu(struct net_device *dev, int new_mtu) } /* + * --------------------------- + * Scatter-Gather support + * --------------------------- + */ + +/* assumes reference to priv->vbus.conn held */ +static int +venettap_sg_decode(struct venettap *priv, void *ptr, int len) +{ + struct venet_sg *vsg; + struct vbus_memctx *ctx; + int ret; + + /* + * SG is enabled, so we need to pull in the venet_sg + * header before we can interpret the rest of the + * packet + * + * FIXME: Make sure this is not too big + */ + if (unlikely(len > priv->vbus.sg.len)) { + kfree(priv->vbus.sg.desc); + priv->vbus.sg.desc = kzalloc(len, GFP_KERNEL); + } + + vsg = priv->vbus.sg.desc; + ctx = priv->vbus.ctx; + + ret = ctx->ops->copy_from(ctx, vsg, ptr, len); + BUG_ON(ret); + + /* + * Non GSO type packets should be constrained by the MTU setting + * on the host + */ + if (!(vsg->flags & VENET_SG_FLAG_GSO) + && (vsg->len > (priv->netif.dev->mtu + ETH_HLEN))) + return -1; + + return vsg->len; +} + +/* + * venettap_sg_import - import an skb in scatter-gather mode + * + * assumes reference to priv->vbus.conn held + */ +static int +venettap_sg_import(struct venettap *priv, struct sk_buff *skb, + void *ptr, int len) +{ + struct venet_sg *vsg = priv->vbus.sg.desc; + struct vbus_memctx *ctx = priv->vbus.ctx; + int remain = len; + int ret; + int i; + + PDEBUG("Importing %d bytes in %d segments\n", len, vsg->count); + + for (i = 0; i < vsg->count; i++) { + struct venet_iov *iov = &vsg->iov[i]; + + if (remain < iov->len) + return -EINVAL; + + PDEBUG("Segment %d: %p/%d\n", i, iov->ptr, iov->len); + + ret = ctx->ops->copy_from(ctx, skb_tail_pointer(skb), + (void *)iov->ptr, + iov->len); + if (ret) + return -EFAULT; + + skb_put(skb, iov->len); + remain -= iov->len; + } + + if (vsg->flags & VENET_SG_FLAG_NEEDS_CSUM + && !skb_partial_csum_set(skb, vsg->csum.start, vsg->csum.offset)) + return -EINVAL; + + if (vsg->flags & VENET_SG_FLAG_GSO) { + struct skb_shared_info *sinfo = skb_shinfo(skb); + + PDEBUG("GSO packet detected\n"); + + switch (vsg->gso.type) { + case VENET_GSO_TYPE_TCPV4: + sinfo->gso_type = SKB_GSO_TCPV4; + break; + case VENET_GSO_TYPE_TCPV6: + sinfo->gso_type = SKB_GSO_TCPV6; + break; + case VENET_GSO_TYPE_UDP: + sinfo->gso_type = SKB_GSO_UDP; + break; + default: + PDEBUG("Illegal GSO type: %d\n", vsg->gso.type); + priv->netif.stats.rx_frame_errors++; + kfree_skb(skb); + return -EINVAL; + } + + if (vsg->flags & VENET_SG_FLAG_ECN) + sinfo->gso_type |= SKB_GSO_TCP_ECN; + + sinfo->gso_size = vsg->gso.size; + if (skb_shinfo(skb)->gso_size == 0) { + PDEBUG("Illegal GSO size: %d\n", vsg->gso.size); + priv->netif.stats.rx_frame_errors++; + kfree_skb(skb); + return -EINVAL; + } + + /* Header must be checked, and gso_segs computed. */ + skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY; + skb_shinfo(skb)->gso_segs = 0; + } + + return 0; +} + +static struct venettap_rx_ops venettap_sg_rx_ops = { + .decode = venettap_sg_decode, + .import = venettap_sg_import, +}; + +/* + * --------------------------- + * Flat (non Scatter-Gather) support + * --------------------------- + */ + +/* assumes reference to priv->vbus.conn held */ +static int +venettap_flat_decode(struct venettap *priv, void *ptr, int len) +{ + size_t maxlen = priv->netif.dev->mtu + ETH_HLEN; + + if (len > maxlen) + return -1; + + /* + * If SG is *not* enabled, the length is simply the + * descriptor length + */ + + return len; +} + +/* + * venettap_rx_flat - import an skb in non scatter-gather mode + * + * assumes reference to priv->vbus.conn held + */ +static int +venettap_flat_import(struct venettap *priv, struct sk_buff *skb, + void *ptr, int len) +{ + struct vbus_memctx *ctx = priv->vbus.ctx; + int ret; + + ret = ctx->ops->copy_from(ctx, skb_tail_pointer(skb), ptr, len); + if (ret) + return -EFAULT; + + skb_put(skb, len); + + return 0; +} + +static struct venettap_rx_ops venettap_flat_rx_ops = { + .decode = venettap_flat_decode, + .import = venettap_flat_import, +}; + +/* * The poll implementation. */ static int @@ -301,6 +491,7 @@ venettap_rx(struct venettap *priv) int ret; unsigned long flags; struct vbus_connection *conn; + struct venettap_rx_ops *rx_ops; PDEBUG("polling...\n"); @@ -324,6 +515,8 @@ venettap_rx(struct venettap *priv) ioq = priv->vbus.rxq.queue; ctx = priv->vbus.ctx; + rx_ops = priv->vbus.rx_ops; + spin_unlock_irqrestore(&priv->lock, flags); /* We want to iterate on the head of the in-use index */ @@ -338,11 +531,14 @@ venettap_rx(struct venettap *priv) * the north side */ while (priv->vbus.link && iter.desc->sown) { - size_t len = iter.desc->len; - size_t maxlen = priv->netif.dev->mtu + ETH_HLEN; struct sk_buff *skb = NULL; + size_t len; - if (unlikely(len > maxlen)) { + len = rx_ops->decode(priv, + (void *)iter.desc->ptr, + iter.desc->len); + + if (unlikely(len < 0)) { priv->netif.stats.rx_errors++; priv->netif.stats.rx_length_errors++; goto next; @@ -360,10 +556,8 @@ venettap_rx(struct venettap *priv) /* align IP on 16B boundary */ skb_reserve(skb, 2); - ret = ctx->ops->copy_from(ctx, skb->data, - (void *)iter.desc->ptr, - len); - if (unlikely(ret)) { + ret = rx_ops->import(priv, skb, (void *)iter.desc->ptr, len); + if (unlikely(ret < 0)) { priv->netif.stats.rx_errors++; goto next; } @@ -843,6 +1037,23 @@ venettap_macquery(struct venettap *priv, void *data, unsigned long len) return 0; } +static u32 +venettap_negcap_sg(struct venettap *priv, u32 requested) +{ + u32 available = VENET_CAP_SG|VENET_CAP_TSO4|VENET_CAP_TSO6 + |VENET_CAP_ECN; + u32 ret; + + ret = available & requested; + + if (ret & VENET_CAP_SG) { + priv->vbus.sg.enabled = true; + priv->vbus.rx_ops = &venettap_sg_rx_ops; + } + + return ret; +} + /* * Negotiate Capabilities - This function is provided so that the * interface may be extended without breaking ABI compatability @@ -870,6 +1081,9 @@ venettap_negcap(struct venettap *priv, void *data, unsigned long len) return -EFAULT; switch (caps.gid) { + case VENET_CAP_GROUP_SG: + caps.bits = venettap_negcap_sg(priv, caps.bits); + break; default: caps.bits = 0; break; @@ -1037,6 +1251,12 @@ venettap_vlink_release(struct vbus_connection *conn) vbus_memctx_put(priv->vbus.ctx); kobject_put(priv->vbus.dev.kobj); + + priv->vbus.sg.enabled = false; + priv->vbus.rx_ops = &venettap_flat_rx_ops; + kfree(priv->vbus.sg.desc); + priv->vbus.sg.desc = NULL; + priv->vbus.sg.len = 0; } static struct vbus_connection_ops venettap_vbus_link_ops = { @@ -1315,6 +1535,8 @@ venettap_device_create(struct vbus_devclass *dc, _vdev->ops = &venettap_device_ops; _vdev->attrs = &venettap_attr_group; + priv->vbus.rx_ops = &venettap_flat_rx_ops; + /* * netif init */ -- 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/