This is the ported version of commit
36d5fe6a with the same name from net-next.
Apart from the small datapath.c changes it adjust the compat layer files as
well. This is the original commit message:
"skb_zerocopy can copy elements of the frags array between skbs, but it doesn't
orphan them. Also, it doesn't handle errors, so this patch takes care of that
as well, and modify the callers accordingly. skb_tx_error() is also added to
the callers so they will signal the failed delivery towards the creator of the
skb."
Signed-off-by: Zoltan Kiss <zoltan.kiss@citrix.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>
}
nla->nla_len = nla_attr_size(skb->len);
}
nla->nla_len = nla_attr_size(skb->len);
- skb_zerocopy(user_skb, skb, skb->len, hlen);
+ err = skb_zerocopy(user_skb, skb, skb->len, hlen);
+ if (err)
+ goto out;
/* Pad OVS_PACKET_ATTR_PACKET if linear copy was performed */
if (!(dp->user_features & OVS_DP_F_UNALIGNED) &&
/* Pad OVS_PACKET_ATTR_PACKET if linear copy was performed */
if (!(dp->user_features & OVS_DP_F_UNALIGNED) &&
err = genlmsg_unicast(ovs_dp_get_net(dp), user_skb, upcall_info->portid);
out:
err = genlmsg_unicast(ovs_dp_get_net(dp), user_skb, upcall_info->portid);
out:
+ if (err)
+ skb_tx_error(skb);
kfree_skb(nskb);
return err;
}
kfree_skb(nskb);
return err;
}
+#if LINUX_VERSION_CODE < KERNEL_VERSION(3,6,0)
+static inline int skb_orphan_frags(struct sk_buff *skb, gfp_t gfp_mask)
+{
+ return 0;
+}
+#endif /* LINUX_VERSION_CODE < KERNEL_VERSION(3,6,0) */
+
#if LINUX_VERSION_CODE < KERNEL_VERSION(3,8,0)
#define __skb_get_rxhash rpl__skb_get_rxhash
#define skb_get_rxhash rpl_skb_get_rxhash
#if LINUX_VERSION_CODE < KERNEL_VERSION(3,8,0)
#define __skb_get_rxhash rpl__skb_get_rxhash
#define skb_get_rxhash rpl_skb_get_rxhash
#endif
return __skb_get_rxhash(skb);
}
#endif
return __skb_get_rxhash(skb);
}
+
+static inline void skb_tx_error(struct sk_buff *skb)
+{
+ return;
+}
+#endif /* LINUX_VERSION_CODE < KERNEL_VERSION(3,8,0) */
#if LINUX_VERSION_CODE < KERNEL_VERSION(3,14,0)
unsigned int skb_zerocopy_headlen(const struct sk_buff *from);
#if LINUX_VERSION_CODE < KERNEL_VERSION(3,14,0)
unsigned int skb_zerocopy_headlen(const struct sk_buff *from);
-void skb_zerocopy(struct sk_buff *to, const struct sk_buff *from, int len,
+int skb_zerocopy(struct sk_buff *to, struct sk_buff *from, int len,
*
* The `hlen` as calculated by skb_zerocopy_headlen() specifies the
* headroom in the `to` buffer.
*
* The `hlen` as calculated by skb_zerocopy_headlen() specifies the
* headroom in the `to` buffer.
+ *
+ * Return value:
+ * 0: everything is OK
+ * -ENOMEM: couldn't orphan frags of @from due to lack of memory
+ * -EFAULT: skb_copy_bits() found some problem with skb geometry
-void
-skb_zerocopy(struct sk_buff *to, const struct sk_buff *from, int len, int hlen)
+int
+skb_zerocopy(struct sk_buff *to, struct sk_buff *from, int len, int hlen)
{
int i, j = 0;
int plen = 0; /* length of skb->head fragment */
{
int i, j = 0;
int plen = 0; /* length of skb->head fragment */
struct page *page;
unsigned int offset;
BUG_ON(!head_frag(from) && !hlen);
/* dont bother with small payloads */
struct page *page;
unsigned int offset;
BUG_ON(!head_frag(from) && !hlen);
/* dont bother with small payloads */
- if (len <= skb_tailroom(to)) {
- skb_copy_bits(from, 0, skb_put(to, len), len);
- return;
- }
+ if (len <= skb_tailroom(to))
+ return skb_copy_bits(from, 0, skb_put(to, len), len);
- skb_copy_bits(from, 0, skb_put(to, hlen), hlen);
+ ret = skb_copy_bits(from, 0, skb_put(to, hlen), hlen);
+ if (unlikely(ret))
+ return ret;
len -= hlen;
} else {
plen = min_t(int, skb_headlen(from), len);
len -= hlen;
} else {
plen = min_t(int, skb_headlen(from), len);
to->len += len + plen;
to->data_len += len + plen;
to->len += len + plen;
to->data_len += len + plen;
+ if (unlikely(skb_orphan_frags(from, GFP_ATOMIC))) {
+ skb_tx_error(from);
+ return -ENOMEM;
+ }
+
for (i = 0; i < skb_shinfo(from)->nr_frags; i++) {
if (!len)
break;
for (i = 0; i < skb_shinfo(from)->nr_frags; i++) {
if (!len)
break;
j++;
}
skb_shinfo(to)->nr_frags = j;
j++;
}
skb_shinfo(to)->nr_frags = j;