net: Clarification of CHECKSUM_UNNECESSARY

This patch:
 - Clarifies the specific requirements of devices returning
   CHECKSUM_UNNECESSARY (comments in skbuff.h).
 - Adds csum_level field to skbuff. This is used to express how
   many checksums are covered by CHECKSUM_UNNECESSARY (stores n - 1).
   This replaces the overloading of skb->encapsulation, that field is
   is now only used to indicate inner headers are valid.
 - Change __skb_checksum_validate_needed to "consume" each checksum
   as indicated by csum_level as layers of the the packet are parsed.
 - Remove skb_pop_rcv_encapsulation, no longer needed in the new
   csum_level model.

Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This commit is contained in:

Tom Herbert

2014-08-27 21:26:46 -07:00

committed by

David S. Miller

parent de20fe8e2c

commit 77cffe23c1

3 changed files with 51 additions and 26 deletions

									
										net/ipv4/gre_demux.c
									
		-1
	
												View File
												
				@@ -125,7 +125,6 @@ static int parse_gre_header(struct sk_buff *skb, struct tnl_ptk_info *tpi,

							*csum_err = true;

							return -EINVAL;

						}

						skb_pop_rcv_encapsulation(skb);

						options++;

					}