lib/interval_tree: fast overlap detection

Allow interval trees to quickly check for overlaps to avoid unnecesary
tree lookups in interval_tree_iter_first().

As of this patch, all interval tree flavors will require using a
'rb_root_cached' such that we can have the leftmost node easily
available. While most users will make use of this feature, those with
special functions (in addition to the generic insert, delete, search
calls) will avoid using the cached option as they can do funky things
with insertions -- for example, vma_interval_tree_insert_after().

[jglisse@redhat.com: fix deadlock from typo vm_lock_anon_vma()]
Link: http://lkml.kernel.org/r/20170808225719.20723-1-jglisse@redhat.com
Link: http://lkml.kernel.org/r/20170719014603.19029-12-dave@stgolabs.net
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Acked-by: Christian König <christian.koenig@amd.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Doug Ledford <dledford@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Christian Benvenuti <benve@cisco.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

usnic: add missing clauses to BSD license

The usnic_verbs kernel module was clearly marked with the following in
its code:

MODULE_LICENSE("Dual BSD/GPL");

However, we accidentally left a few clauses of the BSD text out of the
license header in all the source files. This commit fixes that: all
the files are properly dual BSD/GPL-licensed. Contributors that might
have been confused by this have been contacted to get their permission
and are Cc:ed here.

Cc: Benoit Taine <benoit.taine@lip6.fr>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Masanari Iida <standby24x7@gmail.com>
Cc: Matan Barak <matanb@mellanox.com>
Cc: Michael Wang <yun.wang@profitbricks.com>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Jeff Squyres <jsquyres@cisco.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/usnic: Remove unused includes of <linux/version.h>

Remove including <linux/version.h> that don't need it.

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/usnic: Add Cisco VIC low-level hardware driver

This adds a driver that allows userspace to use UD-like QPs over a
proprietary Cisco transport with Cisco's Virtual Interface Cards (VICs),
including VIC 1240 and 1280 cards.

Signed-off-by: Upinder Malhi <umalhi@cisco.com>
Signed-off-by: Christian Benvenuti <benve@cisco.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>