netvm: propagate page->pfmemalloc to skb

netvm: propagate page->pfmemalloc to skb

The skb->pfmemalloc flag gets set to true iff during the slab allocation
of data in __alloc_skb that the the PFMEMALLOC reserves were used.  If the
packet is fragmented, it is possible that pages will be allocated from the
PFMEMALLOC reserve without propagating this information to the skb.  This
patch propagates page->pfmemalloc from pages allocated for fragments to
the skb.

Signed-off-by: Mel Gorman <[email protected]>
Acked-by: David S. Miller <[email protected]>
Cc: Neil Brown <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Mike Christie <[email protected]>
Cc: Eric B Munson <[email protected]>
Cc: Eric Dumazet <[email protected]>
Cc: Sebastian Andrzej Siewior <[email protected]>
Cc: Mel Gorman <[email protected]>
Cc: Christoph Lameter <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>