user/sven/linux.git/include/linux/skbuff.h, branch v4.7

net_sched: fix mirrored packets checksum

2016-07-01T20:19:34Z

Similar to commit 9b368814b336 ("net: fix bridge multicast packet checksum validation") we need to fixup the checksum for CHECKSUM_COMPLETE when pushing skb on RX path. Otherwise we get similar splats. Cc: Jamal Hadi Salim Cc: Tom Herbert Signed-off-by: Cong Wang Acked-by: Jamal Hadi Salim Signed-off-by: David S. Miller

packet: Use symmetric hash for PACKET_FANOUT_HASH.

2016-07-01T20:07:50Z

People who use PACKET_FANOUT_HASH want a symmetric hash, meaning that they want packets going in both directions on a flow to hash to the same bucket. The core kernel SKB hash became non-symmetric when the ipv6 flow label and other entities were incorporated into the standard flow hash order to increase entropy. But there are no users of PACKET_FANOUT_HASH who want an assymetric hash, they all want a symmetric one. Therefore, use the flow dissector to compute a flat symmetric hash over only the protocol, addresses and ports. This hash does not get installed into and override the normal skb hash, so this change has no effect whatsoever on the rest of the stack. Reported-by: Eric Leblond Tested-by: Eric Leblond Signed-off-by: David S. Miller

net: suppress warnings on dev_alloc_skb

2016-05-20T23:58:32Z

Noticed an allocation failure in a network driver the other day on a 32 bit system: DMA-API: debugging out of memory - disabling bnx2fc: adapter_lookup: hba NULL lldpad: page allocation failure. order:0, mode:0x4120 Pid: 4556, comm: lldpad Not tainted 2.6.32-639.el6.i686.debug #1 Call Trace: [] ? printk+0x19/0x23 [] ? __alloc_pages_nodemask+0x664/0x830 [] ? free_object+0x82/0xa0 [] ? ixgbe_alloc_rx_buffers+0x10b/0x1d0 [ixgbe] [] ? ixgbe_configure_rx_ring+0x29f/0x420 [ixgbe] [] ? ixgbe_configure_tx_ring+0x15c/0x220 [ixgbe] [] ? ixgbe_configure+0x589/0xc00 [ixgbe] [] ? ixgbe_open+0xa7/0x5c0 [ixgbe] [] ? ixgbe_init_interrupt_scheme+0x5b6/0x970 [ixgbe] [] ? ixgbe_setup_tc+0x1a4/0x260 [ixgbe] [] ? ixgbe_dcbnl_set_state+0x7f/0x90 [ixgbe] [] ? dcb_doit+0x10ed/0x16d0 ... Thought that perhaps the big splat in the logs wasn't really necessecary, as all call sites for dev_alloc_skb: a) check the return code for the function and b) either print their own error message or have a recovery path that makes the warning moot. Fix it by modifying dev_alloc_pages to pass __GFP_NOWARN as a gfp flag to suppress the warning applies to the net tree Signed-off-by: Neil Horman CC: "David S. Miller" CC: Eric Dumazet CC: Alexander Duyck Acked-by: Eric Dumazet Signed-off-by: David S. Miller

net: define gso types for IPx over IPv4 and IPv6

2016-05-20T22:03:15Z

This patch defines two new GSO definitions SKB_GSO_IPXIP4 and SKB_GSO_IPXIP6 along with corresponding NETIF_F_GSO_IPXIP4 and NETIF_F_GSO_IPXIP6. These are used to described IP in IP tunnel and what the outer protocol is. The inner protocol can be deduced from other GSO types (e.g. SKB_GSO_TCPV4 and SKB_GSO_TCPV6). The GSO types of SKB_GSO_IPIP and SKB_GSO_SIT are removed (these are both instances of SKB_GSO_IPXIP4). SKB_GSO_IPXIP6 will be used when support for GSO with IP encapsulation over IPv6 is added. Signed-off-by: Tom Herbert Acked-by: Jeff Kirsher Signed-off-by: David S. Miller

net: relax expensive skb_unclone() in iptunnel_handle_offloads()

2016-05-03T04:22:19Z

Locally generated TCP GSO packets having to go through a GRE/SIT/IPIP tunnel have to go through an expensive skb_unclone() Reallocating skb->head is a lot of work. Test should really check if a 'real clone' of the packet was done. TCP does not care if the original gso_type is changed while the packet travels in the stack. This adds skb_header_unclone() which is a variant of skb_clone() using skb_header_cloned() check instead of skb_cloned(). This variant can probably be used from other points. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller

tcp: remove SKBTX_ACK_TSTAMP since it is redundant

2016-04-28T20:06:10Z

The SKBTX_ACK_TSTAMP flag is set in skb_shinfo->tx_flags when the timestamp of the TCP acknowledgement should be reported on error queue. Since accessing skb_shinfo is likely to incur a cache-line miss at the time of receiving the ack, the txstamp_ack bit was added in tcp_skb_cb, which is set iff the SKBTX_ACK_TSTAMP flag is set for an skb. This makes SKBTX_ACK_TSTAMP flag redundant. Remove the SKBTX_ACK_TSTAMP and instead use the txstamp_ack bit everywhere. Note that this frees one bit in shinfo->tx_flags. Signed-off-by: Soheil Hassas Yeganeh Acked-by: Martin KaFai Lau Suggested-by: Willem de Bruijn Acked-by: Eric Dumazet Signed-off-by: David S. Miller

skbuff: Add pskb_extract() helper function

2016-04-25T20:54:14Z

A pattern of skb usage seen in modules such as RDS-TCP is to extract `to_copy' bytes from the received TCP segment, starting at some offset `off' into a new skb `clone'. This is done in the ->data_ready callback, where the clone skb is queued up for rx on the PF_RDS socket, while the parent TCP segment is returned unchanged back to the TCP engine. The existing code uses the sequence clone = skb_clone(..); pskb_pull(clone, off, ..); pskb_trim(clone, to_copy, ..); with the intention of discarding the first `off' bytes. However, skb_clone() + pskb_pull() implies pksb_expand_head(), which ends up doing a redundant memcpy of bytes that will then get discarded in __pskb_pull_tail(). To avoid this inefficiency, this commit adds pskb_extract() that creates the clone, and memcpy's only the relevant header/frag/frag_list to the start of `clone'. pskb_trim() is then invoked to trim clone down to the requested to_copy bytes. Signed-off-by: Sowmini Varadhan Signed-off-by: David S. Miller

GSO: Support partial segmentation offload

2016-04-14T20:23:41Z

This patch adds support for something I am referring to as GSO partial. The basic idea is that we can support a broader range of devices for segmentation if we use fixed outer headers and have the hardware only really deal with segmenting the inner header. The idea behind the naming is due to the fact that everything before csum_start will be fixed headers, and everything after will be the region that is handled by hardware. With the current implementation it allows us to add support for the following GSO types with an inner TSO_MANGLEID or TSO6 offload: NETIF_F_GSO_GRE NETIF_F_GSO_GRE_CSUM NETIF_F_GSO_IPIP NETIF_F_GSO_SIT NETIF_F_UDP_TUNNEL NETIF_F_UDP_TUNNEL_CSUM In the case of hardware that already supports tunneling we may be able to extend this further to support TSO_TCPV4 without TSO_MANGLEID if the hardware can support updating inner IPv4 headers. Signed-off-by: Alexander Duyck Signed-off-by: David S. Miller

GSO: Add GSO type for fixed IPv4 ID

2016-04-14T20:23:40Z

This patch adds support for TSO using IPv4 headers with a fixed IP ID field. This is meant to allow us to do a lossless GRO in the case of TCP flows that use a fixed IP ID such as those that convert IPv6 header to IPv4 headers. In addition I am adding a feature that for now I am referring to TSO with IP ID mangling. Basically when this flag is enabled the device has the option to either output the flow with incrementing IP IDs or with a fixed IP ID regardless of what the original IP ID ordering was. This is useful in cases where the DF bit is set and we do not care if the original IP ID value is maintained. Signed-off-by: Alexander Duyck Signed-off-by: David S. Miller

udp: enable MSG_PEEK at non-zero offset

2016-04-05T20:29:37Z

Enable peeking at UDP datagrams at the offset specified with socket option SOL_SOCKET/SO_PEEK_OFF. Peek at any datagram in the queue, up to the end of the given datagram. Implement the SO_PEEK_OFF semantics introduced in commit ef64a54f6e55 ("sock: Introduce the SO_PEEK_OFF sock option"). Increase the offset on peek, decrease it on regular reads. When peeking, always checksum the packet immediately, to avoid recomputation on subsequent peeks and final read. The socket lock is not held for the duration of udp_recvmsg, so peek and read operations can run concurrently. Only the last store to sk_peek_off is preserved. Signed-off-by: Sam Kumar Signed-off-by: Willem de Bruijn Signed-off-by: David S. Miller