[PATCH v7 41/46] macvtap: TUN_VNET_LE support

Michael S. Tsirkin
2014-11-30T15:13:07Z

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Jason Wang <jasowang@redhat.com>
---
drivers/net/macvtap.c | 68 ++++++++++++++++++++++++++++++++-------------------
1 file changed, 43 insertions(+), 25 deletions(-)

diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c
index 880cc09..af90ab5 100644
--- a/drivers/net/macvtap.c
+++ b/drivers/net/macvtap.c
@@ -45,6 +45,18 @@ struct macvtap_queue {
struct list_head next;
};

+#define MACVTAP_FEATURES (IFF_VNET_HDR | IFF_VNET_LE | IFF_MULTI_QUEUE)
+
+static inline u16 macvtap16_to_cpu(struct macvtap_queue *q, __virtio16 val)
+{
+ return __virtio16_to_cpu(q->flags & IFF_VNET_LE, val);
+}
+
+static inline __virtio16 cpu_to_macvtap16(struct macvtap_queue *q, u16 val)
+{
+ return __cpu_to_virtio16(q->flags & IFF_VNET_LE, val);
+}
+
static struct proto macvtap_proto = {
.name = "macvtap",
.owner = THIS_MODULE,
@@ -557,7 +569,8 @@ static inline struct sk_buff *macvtap_alloc_skb(struct sock *sk, size_t prepad,
* macvtap_skb_from_vnet_hdr and macvtap_skb_to_vnet_hdr should
* be shared with the tun/tap driver.
*/
-static int macvtap_skb_from_vnet_hdr(struct sk_buff *skb,
+static int macvtap_skb_from_vnet_hdr(struct macvtap_queue *q,
+ struct sk_buff *skb,
struct virtio_net_hdr *vnet_hdr)
{
unsigned short gso_type = 0;
@@ -588,13 +601,13 @@ static int macvtap_skb_from_vnet_hdr(struct sk_buff *skb,
}

if (vnet_hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
- if (!skb_partial_csum_set(skb, vnet_hdr->csum_start,
- vnet_hdr->csum_offset))
+ if (!skb_partial_csum_set(skb, macvtap16_to_cpu(q, vnet_hdr->csum_start),
+ macvtap16_to_cpu(q, vnet_hdr->csum_offset)))
return -EINVAL;
}

if (vnet_hdr->gso_type != VIRTIO_NET_HDR_GSO_NONE) {
- skb_shinfo(skb)->gso_size = vnet_hdr->gso_size;
+ skb_shinfo(skb)->gso_size = macvtap16_to_cpu(q, vnet_hdr->gso_size);
skb_shinfo(skb)->gso_type = gso_type;

/* Header must be checked, and gso_segs computed. */
@@ -604,8 +617,9 @@ static int macvtap_skb_from_vnet_hdr(struct sk_buff *skb,
return 0;
}

-static void macvtap_skb_to_vnet_hdr(const struct sk_buff *skb,
- struct virtio_net_hdr *vnet_hdr)
+static void macvtap_skb_to_vnet_hdr(struct macvtap_queue *q,
+ const struct sk_buff *skb,
+ struct virtio_net_hdr *vnet_hdr)
{
memset(vnet_hdr, 0, sizeof(*vnet_hdr));

@@ -613,8 +627,8 @@ static void macvtap_skb_to_vnet_hdr(const struct sk_buff *skb,
struct skb_shared_info *sinfo = skb_shinfo(skb);

/* This is a hint as to how much should be linear. */
- vnet_hdr->hdr_len = skb_headlen(skb);
- vnet_hdr->gso_size = sinfo->gso_size;
+ vnet_hdr->hdr_len = cpu_to_macvtap16(q, skb_headlen(skb));
+ vnet_hdr->gso_size = cpu_to_macvtap16(q, sinfo->gso_size);
if (sinfo->gso_type & SKB_GSO_TCPV4)
vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
else if (sinfo->gso_type & SKB_GSO_TCPV6)
@@ -628,10 +642,13 @@ static void macvtap_skb_to_vnet_hdr(const struct sk_buff *skb,

if (skb->ip_summed == CHECKSUM_PARTIAL) {
vnet_hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
- vnet_hdr->csum_start = skb_checksum_start_offset(skb);
if (vlan_tx_tag_present(skb))
- vnet_hdr->csum_start += VLAN_HLEN;
- vnet_hdr->csum_offset = skb->csum_offset;
+ vnet_hdr->csum_start = cpu_to_macvtap16(q,
+ skb_checksum_start_offset(skb) + VLAN_HLEN);
+ else
+ vnet_hdr->csum_start = cpu_to_macvtap16(q,
+ skb_checksum_start_offset(skb));
+ vnet_hdr->csum_offset = cpu_to_macvtap16(q, skb->csum_offset);
} else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
vnet_hdr->flags = VIRTIO_NET_HDR_F_DATA_VALID;
} /* else everything is zero */
@@ -666,12 +683,14 @@ static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m,
if (err < 0)
goto err;
if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
- vnet_hdr.csum_start + vnet_hdr.csum_offset + 2 >
- vnet_hdr.hdr_len)
- vnet_hdr.hdr_len = vnet_hdr.csum_start +
- vnet_hdr.csum_offset + 2;
+ macvtap16_to_cpu(q, vnet_hdr.csum_start) +
+ macvtap16_to_cpu(q, vnet_hdr.csum_offset) + 2 >
+ macvtap16_to_cpu(q, vnet_hdr.hdr_len))
+ vnet_hdr.hdr_len = cpu_to_macvtap16(q,
+ macvtap16_to_cpu(q, vnet_hdr.csum_start) +
+ macvtap16_to_cpu(q, vnet_hdr.csum_offset) + 2);
err = -EINVAL;
- if (vnet_hdr.hdr_len > len)
+ if (macvtap16_to_cpu(q, vnet_hdr.hdr_len) > len)
goto err;
}

@@ -684,7 +703,8 @@ static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m,
goto err;

if (m && m->msg_control && sock_flag(&q->sk, SOCK_ZEROCOPY)) {
- copylen = vnet_hdr.hdr_len ? vnet_hdr.hdr_len : GOODCOPY_LEN;
+ copylen = vnet_hdr.hdr_len ?
+ macvtap16_to_cpu(q, vnet_hdr.hdr_len) : GOODCOPY_LEN;
if (copylen > good_linear)
copylen = good_linear;
linear = copylen;
@@ -695,10 +715,10 @@ static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m,

if (!zerocopy) {
copylen = len;
- if (vnet_hdr.hdr_len > good_linear)
+ if (macvtap16_to_cpu(q, vnet_hdr.hdr_len) > good_linear)
linear = good_linear;
else
- linear = vnet_hdr.hdr_len;
+ linear = macvtap16_to_cpu(q, vnet_hdr.hdr_len);
}

skb = macvtap_alloc_skb(&q->sk, NET_IP_ALIGN, copylen,
@@ -725,7 +745,7 @@ static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m,
skb->protocol = eth_hdr(skb)->h_proto;

if (vnet_hdr_len) {
- err = macvtap_skb_from_vnet_hdr(skb, &vnet_hdr);
+ err = macvtap_skb_from_vnet_hdr(q, skb, &vnet_hdr);
if (err)
goto err_kfree;
}
@@ -791,7 +811,7 @@ static ssize_t macvtap_put_user(struct macvtap_queue *q,
if ((len -= vnet_hdr_len) < 0)
return -EINVAL;

- macvtap_skb_to_vnet_hdr(skb, &vnet_hdr);
+ macvtap_skb_to_vnet_hdr(q, skb, &vnet_hdr);

if (memcpy_toiovecend(iv, (void *)&vnet_hdr, 0, sizeof(vnet_hdr)))
return -EFAULT;
@@ -1003,8 +1023,7 @@ static long macvtap_ioctl(struct file *file, unsigned int cmd,
return -EFAULT;

ret = 0;
- if ((u & ~(IFF_VNET_HDR | IFF_MULTI_QUEUE)) !=
- (IFF_NO_PI | IFF_TAP))
+ if ((u & ~MACVTAP_FEATURES) != (IFF_NO_PI | IFF_TAP))
ret = -EINVAL;
else
q->flags = u;
@@ -1036,8 +1055,7 @@ static long macvtap_ioctl(struct file *file, unsigned int cmd,
return ret;

case TUNGETFEATURES:
- if (put_user(IFF_TAP | IFF_NO_PI | IFF_VNET_HDR |
- IFF_MULTI_QUEUE, up))
+ if (put_user(IFF_TAP | IFF_NO_PI | MACVTAP_FEATURES, up))
return -EFAULT;
return 0;

--
MST