1/* SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause */
2/*
3 * Copyright(c) 2020 Cornelis Networks, Inc.
4 * Copyright(c) 2016 Intel Corporation.
5 */
6
7#ifndef _HFI1_MMU_RB_H
8#define _HFI1_MMU_RB_H
9
10#include "hfi.h"
11
12struct mmu_rb_node {
13	unsigned long addr;
14	unsigned long len;
15	unsigned long __last;
16	struct rb_node node;
17	struct mmu_rb_handler *handler;
18	struct list_head list;
19	struct kref refcount;
20};
21
22/* filter and evict must not sleep. Only remove is allowed to sleep. */
23struct mmu_rb_ops {
24	bool (*filter)(struct mmu_rb_node *node, unsigned long addr,
25		       unsigned long len);
26	void (*remove)(void *ops_arg, struct mmu_rb_node *mnode);
27	int (*evict)(void *ops_arg, struct mmu_rb_node *mnode,
28		     void *evict_arg, bool *stop);
29};
30
31struct mmu_rb_handler {
32	/*
33	 * struct mmu_notifier is 56 bytes, and spinlock_t is 4 bytes, so
34	 * they fit together in one cache line.  mn is relatively rarely
35	 * accessed, so co-locating the spinlock with it achieves much of
36	 * the cacheline contention reduction of giving the spinlock its own
37	 * cacheline without the overhead of doing so.
38	 */
39	struct mmu_notifier mn;
40	spinlock_t lock;        /* protect the RB tree */
41
42	/* Begin on a new cachline boundary here */
43	struct rb_root_cached root ____cacheline_aligned_in_smp;
44	void *ops_arg;
45	struct mmu_rb_ops *ops;
46	struct list_head lru_list;
47	struct work_struct del_work;
48	struct list_head del_list;
49	struct workqueue_struct *wq;
50	void *free_ptr;
51};
52
53int hfi1_mmu_rb_register(void *ops_arg,
54			 struct mmu_rb_ops *ops,
55			 struct workqueue_struct *wq,
56			 struct mmu_rb_handler **handler);
57void hfi1_mmu_rb_unregister(struct mmu_rb_handler *handler);
58int hfi1_mmu_rb_insert(struct mmu_rb_handler *handler,
59		       struct mmu_rb_node *mnode);
60void hfi1_mmu_rb_release(struct kref *refcount);
61
62void hfi1_mmu_rb_evict(struct mmu_rb_handler *handler, void *evict_arg);
63struct mmu_rb_node *hfi1_mmu_rb_get_first(struct mmu_rb_handler *handler,
64					  unsigned long addr,
65					  unsigned long len);
66
67#endif /* _HFI1_MMU_RB_H */
68