Merge branch 'ebpf_maps'

Alexei Starovoitov says:

====================
implementation of eBPF maps

v1->v2:
renamed flags for MAP_UPDATE_ELEM command to be more concise,
clarified commit logs and improved comments in patches 1,3,7
per discussions with Daniel

Old v1 cover:

this set of patches adds implementation of HASH and ARRAY types of eBPF maps
which were described in manpage in commit b4fc1a460f30("Merge branch 'bpf-next'")

The difference vs previous version of these patches from August:
- added 'flags' attribute to BPF_MAP_UPDATE_ELEM
- in HASH type implementation removed per-map kmem_cache.
  I was doing kmem_cache_create() for every map to enable selective slub
  debugging to check for overflows and leaks. Now it's not needed, so just
  use normal kmalloc() for map elements.
- added ARRAY type which was mentioned in manpage, but wasn't public yet
- added map testsuite and removed temporary bits from test_stubs

Note, eBPF programs cannot be attached to events yet.
It will come in the next set.
====================

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