linux/drivers/infiniband/hw/usnic/usnic_uiom_interval_tree.h
Davidlohr Bueso f808c13fd3 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>
2017-09-08 18:26:49 -07:00

89 lines
3.2 KiB
C

/*
* Copyright (c) 2013, Cisco Systems, Inc. All rights reserved.
*
* This software is available to you under a choice of one of two
* licenses. You may choose to be licensed under the terms of the GNU
* General Public License (GPL) Version 2, available from the file
* COPYING in the main directory of this source tree, or the
* BSD license below:
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* - Redistributions of source code must retain the above
* copyright notice, this list of conditions and the following
* disclaimer.
*
* - Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*
*/
#ifndef USNIC_UIOM_INTERVAL_TREE_H_
#define USNIC_UIOM_INTERVAL_TREE_H_
#include <linux/rbtree.h>
struct usnic_uiom_interval_node {
struct rb_node rb;
struct list_head link;
unsigned long start;
unsigned long last;
unsigned long __subtree_last;
unsigned int ref_cnt;
int flags;
};
extern void
usnic_uiom_interval_tree_insert(struct usnic_uiom_interval_node *node,
struct rb_root_cached *root);
extern void
usnic_uiom_interval_tree_remove(struct usnic_uiom_interval_node *node,
struct rb_root_cached *root);
extern struct usnic_uiom_interval_node *
usnic_uiom_interval_tree_iter_first(struct rb_root_cached *root,
unsigned long start,
unsigned long last);
extern struct usnic_uiom_interval_node *
usnic_uiom_interval_tree_iter_next(struct usnic_uiom_interval_node *node,
unsigned long start, unsigned long last);
/*
* Inserts {start...last} into {root}. If there are overlaps,
* nodes will be broken up and merged
*/
int usnic_uiom_insert_interval(struct rb_root_cached *root,
unsigned long start, unsigned long last,
int flags);
/*
* Removed {start...last} from {root}. The nodes removed are returned in
* 'removed.' The caller is responsibile for freeing memory of nodes in
* 'removed.'
*/
void usnic_uiom_remove_interval(struct rb_root_cached *root,
unsigned long start, unsigned long last,
struct list_head *removed);
/*
* Returns {start...last} - {root} (relative complement of {start...last} in
* {root}) in diff_set sorted ascendingly
*/
int usnic_uiom_get_intervals_diff(unsigned long start,
unsigned long last, int flags,
int flag_mask,
struct rb_root_cached *root,
struct list_head *diff_set);
/* Call this to free diff_set returned by usnic_uiom_get_intervals_diff */
void usnic_uiom_put_interval_set(struct list_head *intervals);
#endif /* USNIC_UIOM_INTERVAL_TREE_H_ */