Merge branch 'Convert-skb_frag_t-to-bio_vec'

Matthew Wilcox says:

====================
Convert skb_frag_t to bio_vec

The skb_frag_t and bio_vec are fundamentally the same (page, offset,
length) tuple.  This patch series unifies the two, leaving the
skb_frag_t typedef in place.  This has the immediate advantage that
we already have iov_iter support for bvecs and don't need to add
support for iterating skbuffs.  It enables a long-term plan to use
bvecs more broadly within the kernel and should make network-storage
drivers able to do less work converting between skbuffs and biovecs.

It will consume more memory on 32-bit kernels.  If that proves
problematic, we can look at ways of addressing it.

v3: Rebase on latest Linus with net-next merged.
  - Reorder the uncontroversial 'Use skb accessors' patches first so you
    can apply just those two if you want to hold off on the full
    conversion.
  - Convert all the users of 'struct skb_frag_struct' to skb_frag_t.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>