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authorDavid S. Miller <davem@davemloft.net>2016-03-08 20:34:12 +0300
committerDavid S. Miller <davem@davemloft.net>2016-03-08 20:34:12 +0300
commit810813c47a564416f6306ae214e2661366c987a7 (patch)
treef0d1f856d4b0024324f642fe519963248828b83f /include/linux/skbuff.h
parentd66ab51442211158b677c2f12310c314d9587f74 (diff)
parente2857b8f11a289ed2b61d18d0665e05c1053c446 (diff)
downloadlinux-810813c47a564416f6306ae214e2661366c987a7.tar.xz
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Several cases of overlapping changes, as well as one instance (vxlan) of a bug fix in 'net' overlapping with code movement in 'net-next'. Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/linux/skbuff.h')
-rw-r--r--include/linux/skbuff.h24
1 files changed, 24 insertions, 0 deletions
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 797cefb888fb..15d0df943466 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -1981,6 +1981,30 @@ static inline void skb_reserve(struct sk_buff *skb, int len)
skb->tail += len;
}
+/**
+ * skb_tailroom_reserve - adjust reserved_tailroom
+ * @skb: buffer to alter
+ * @mtu: maximum amount of headlen permitted
+ * @needed_tailroom: minimum amount of reserved_tailroom
+ *
+ * Set reserved_tailroom so that headlen can be as large as possible but
+ * not larger than mtu and tailroom cannot be smaller than
+ * needed_tailroom.
+ * The required headroom should already have been reserved before using
+ * this function.
+ */
+static inline void skb_tailroom_reserve(struct sk_buff *skb, unsigned int mtu,
+ unsigned int needed_tailroom)
+{
+ SKB_LINEAR_ASSERT(skb);
+ if (mtu < skb_tailroom(skb) - needed_tailroom)
+ /* use at most mtu */
+ skb->reserved_tailroom = skb_tailroom(skb) - mtu;
+ else
+ /* use up to all available space */
+ skb->reserved_tailroom = needed_tailroom;
+}
+
#define ENCAP_TYPE_ETHER 0
#define ENCAP_TYPE_IPPROTO 1