A latter patch will postpone the delivery_time clearing until the stack
knows the skb is being delivered locally. That will allow other kernel
forwarding path (e.g. ip[6]_forward) to keep the delivery_time also.
An earlier attempt was to do skb_clear_delivery_time() in
ip_local_deliver() and ip6_input(). The discussion [0] requested
to move it one step later into ip_local_deliver_finish()
and ip6_input_finish() so that the delivery_time can be kept
for the ip_vs forwarding path also.
To do that, this patch also needs to take care of the (rcv) timestamp
usecase in ip_is_fragment(). It needs to expect delivery_time in
the skb->tstamp, so it needs to save the mono_delivery_time bit in
inet_frag_queue such that the delivery_time (if any) can be restored
in the final defragmented skb.
[Note that it will only happen when the locally generated skb is looping
from egress to ingress over a virtual interface (e.g. veth, loopback...),
skb->tstamp may have the delivery time before it is known that it will
be delivered locally and received by another sk.]
[0]: https://lore.kernel.org/netdev/
ca728d81-80e8-3767-d5e-
d44f6ad96e43@ssi.bg/
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* @stamp: timestamp of the last received fragment
* @len: total length of the original datagram
* @meat: length of received fragments so far
+ * @mono_delivery_time: stamp has a mono delivery time (EDT)
* @flags: fragment queue flags
* @max_size: maximum received fragment size
* @fqdir: pointer to struct fqdir
ktime_t stamp;
int len;
int meat;
+ u8 mono_delivery_time;
__u8 flags;
u16 max_size;
struct fqdir *fqdir;
skb_mark_not_on_list(head);
head->prev = NULL;
head->tstamp = q->stamp;
+ head->mono_delivery_time = q->mono_delivery_time;
}
EXPORT_SYMBOL(inet_frag_reasm_finish);
qp->iif = dev->ifindex;
qp->q.stamp = skb->tstamp;
+ qp->q.mono_delivery_time = skb->mono_delivery_time;
qp->q.meat += skb->len;
qp->ecn |= ecn;
add_frag_mem_limit(qp->q.fqdir, skb->truesize);