kcm: Send multiple frags in one sendmsg()

Rewrite the AF_KCM transmission loop to send all the fragments in a single
skb or frag_list-skb in one sendmsg() with MSG_SPLICE_PAGES set.  The list
of fragments in each skb is conveniently a bio_vec[] that can just be
attached to a BVEC iter.

Note: I'm working out the size of each fragment-skb by adding up bv_len for
all the bio_vecs in skb->frags[] - but surely this information is recorded
somewhere?  For the skbs in head->frag_list, this is equal to
skb->data_len, but not for the head.  head->data_len includes all the tail
frags too.

Signed-off-by: David Howells <[email protected]>
cc: Tom Herbert <[email protected]>
cc: Tom Herbert <[email protected]>
cc: Jens Axboe <[email protected]>
cc: Matthew Wilcox <[email protected]>
Signed-off-by: Jakub Kicinski <[email protected]>

0 files changed, 0 insertions, 0 deletions