net: move gso declarations and functions to their own files

Move declarations into include/net/gso.h and code into net/core/gso.c

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Stanislav Fomichev <sdf@google.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20230608191738.3947077-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 1 insertions, 141 deletions

diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 7c4338221b17..fee2b1c105fe 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -67,6 +67,7 @@
 #include <net/dst.h>
 #include <net/sock.h>
 #include <net/checksum.h>
+#include <net/gso.h>
 #include <net/ip6_checksum.h>
 #include <net/xfrm.h>
 #include <net/mpls.h>
@@ -5766,147 +5767,6 @@ void skb_scrub_packet(struct sk_buff *skb, bool xnet)
 }
 EXPORT_SYMBOL_GPL(skb_scrub_packet);
 
-/**
- * skb_gso_transport_seglen - Return length of individual segments of a gso packet
- *
- * @skb: GSO skb
- *
- * skb_gso_transport_seglen is used to determine the real size of the
- * individual segments, including Layer4 headers (TCP/UDP).
- *
- * The MAC/L2 or network (IP, IPv6) headers are not accounted for.
- */
-static unsigned int skb_gso_transport_seglen(const struct sk_buff *skb)
-{
-	const struct skb_shared_info *shinfo = skb_shinfo(skb);
-	unsigned int thlen = 0;
-
-	if (skb->encapsulation) {
-		thlen = skb_inner_transport_header(skb) -
-			skb_transport_header(skb);
-
-		if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6)))
-			thlen += inner_tcp_hdrlen(skb);
-	} else if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6))) {
-		thlen = tcp_hdrlen(skb);
-	} else if (unlikely(skb_is_gso_sctp(skb))) {
-		thlen = sizeof(struct sctphdr);
-	} else if (shinfo->gso_type & SKB_GSO_UDP_L4) {
-		thlen = sizeof(struct udphdr);
-	}
-	/* UFO sets gso_size to the size of the fragmentation
-	 * payload, i.e. the size of the L4 (UDP) header is already
-	 * accounted for.
-	 */
-	return thlen + shinfo->gso_size;
-}
-
-/**
- * skb_gso_network_seglen - Return length of individual segments of a gso packet
- *
- * @skb: GSO skb
- *
- * skb_gso_network_seglen is used to determine the real size of the
- * individual segments, including Layer3 (IP, IPv6) and L4 headers (TCP/UDP).
- *
- * The MAC/L2 header is not accounted for.
- */
-static unsigned int skb_gso_network_seglen(const struct sk_buff *skb)
-{
-	unsigned int hdr_len = skb_transport_header(skb) -
-			       skb_network_header(skb);
-
-	return hdr_len + skb_gso_transport_seglen(skb);
-}
-
-/**
- * skb_gso_mac_seglen - Return length of individual segments of a gso packet
- *
- * @skb: GSO skb
- *
- * skb_gso_mac_seglen is used to determine the real size of the
- * individual segments, including MAC/L2, Layer3 (IP, IPv6) and L4
- * headers (TCP/UDP).
- */
-static unsigned int skb_gso_mac_seglen(const struct sk_buff *skb)
-{
-	unsigned int hdr_len = skb_transport_header(skb) - skb_mac_header(skb);
-
-	return hdr_len + skb_gso_transport_seglen(skb);
-}
-
-/**
- * skb_gso_size_check - check the skb size, considering GSO_BY_FRAGS
- *
- * There are a couple of instances where we have a GSO skb, and we
- * want to determine what size it would be after it is segmented.
- *
- * We might want to check:
- * -    L3+L4+payload size (e.g. IP forwarding)
- * - L2+L3+L4+payload size (e.g. sanity check before passing to driver)
- *
- * This is a helper to do that correctly considering GSO_BY_FRAGS.
- *
- * @skb: GSO skb
- *
- * @seg_len: The segmented length (from skb_gso_*_seglen). In the
- *           GSO_BY_FRAGS case this will be [header sizes + GSO_BY_FRAGS].
- *
- * @max_len: The maximum permissible length.
- *
- * Returns true if the segmented length <= max length.
- */
-static inline bool skb_gso_size_check(const struct sk_buff *skb,
-				      unsigned int seg_len,
-				      unsigned int max_len) {
-	const struct skb_shared_info *shinfo = skb_shinfo(skb);
-	const struct sk_buff *iter;
-
-	if (shinfo->gso_size != GSO_BY_FRAGS)
-		return seg_len <= max_len;
-
-	/* Undo this so we can re-use header sizes */
-	seg_len -= GSO_BY_FRAGS;
-
-	skb_walk_frags(skb, iter) {
-		if (seg_len + skb_headlen(iter) > max_len)
-			return false;
-	}
-
-	return true;
-}
-
-/**
- * skb_gso_validate_network_len - Will a split GSO skb fit into a given MTU?
- *
- * @skb: GSO skb
- * @mtu: MTU to validate against
- *
- * skb_gso_validate_network_len validates if a given skb will fit a
- * wanted MTU once split. It considers L3 headers, L4 headers, and the
- * payload.
- */
-bool skb_gso_validate_network_len(const struct sk_buff *skb, unsigned int mtu)
-{
-	return skb_gso_size_check(skb, skb_gso_network_seglen(skb), mtu);
-}
-EXPORT_SYMBOL_GPL(skb_gso_validate_network_len);
-
-/**
- * skb_gso_validate_mac_len - Will a split GSO skb fit in a given length?
- *
- * @skb: GSO skb
- * @len: length to validate against
- *
- * skb_gso_validate_mac_len validates if a given skb will fit a wanted
- * length once split, including L2, L3 and L4 headers and the payload.
- */
-bool skb_gso_validate_mac_len(const struct sk_buff *skb, unsigned int len)
-{
-	return skb_gso_size_check(skb, skb_gso_mac_seglen(skb), len);
-}
-EXPORT_SYMBOL_GPL(skb_gso_validate_mac_len);
-
 static struct sk_buff *skb_reorder_vlan_header(struct sk_buff *skb)
 {
 	int mac_len, meta_len;