master
1/* $NetBSD: vnode_impl.h,v 1.24 2022/07/18 04:30:30 thorpej Exp $ */
2
3/*-
4 * Copyright (c) 2016, 2019, 2020 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
17 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
20 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26 * POSSIBILITY OF SUCH DAMAGE.
27 */
28
29#ifndef _SYS_VNODE_IMPL_H_
30#define _SYS_VNODE_IMPL_H_
31#if defined(_KERNEL) || defined(_KMEMUSER)
32
33#include <sys/vnode.h>
34
35struct namecache;
36struct nchnode;
37
38enum vnode_state {
39 VS_ACTIVE, /* Assert only, fs node attached and usecount > 0. */
40 VS_MARKER, /* Stable, used as marker. Will not change. */
41 VS_LOADING, /* Intermediate, initialising the fs node. */
42 VS_LOADED, /* Stable, valid fs node attached. */
43 VS_BLOCKED, /* Intermediate, active, no new references allowed. */
44 VS_RECLAIMING, /* Intermediate, detaching the fs node. */
45 VS_RECLAIMED /* Stable, no fs node attached. */
46};
47
48TAILQ_HEAD(vnodelst, vnode_impl);
49typedef struct vnodelst vnodelst_t;
50
51struct vcache_key {
52 struct mount *vk_mount;
53 const void *vk_key;
54 size_t vk_key_len;
55};
56
57/*
58 * Reading or writing any of these items requires holding the appropriate
59 * lock. Field markings and the corresponding locks:
60 *
61 * - stable throughout the life of the vnode
62 * c vcache_lock
63 * d vdrain_lock
64 * i v_interlock
65 * l vi_nc_listlock
66 * m mnt_vnodelock
67 * n vi_nc_lock
68 * n,l vi_nc_lock + vi_nc_listlock to modify
69 * s syncer_data_lock
70 */
71struct vnode_impl {
72 struct vnode vi_vnode;
73
74 /*
75 * Largely stable data.
76 */
77 struct vcache_key vi_key; /* c vnode cache key */
78
79 /*
80 * The vnode klist is accessed frequently, but rarely
81 * modified.
82 */
83 struct vnode_klist vi_klist; /* i kevent / knote state */
84
85 /*
86 * vnode cache, LRU and syncer. This all changes with some
87 * regularity so keep it together.
88 */
89 struct vnodelst *vi_lrulisthd; /* d current lru list head */
90 TAILQ_ENTRY(vnode_impl) vi_lrulist; /* d lru list */
91 int vi_synclist_slot; /* s synclist slot index */
92 int vi_lrulisttm; /* i time of lru enqueue */
93 TAILQ_ENTRY(vnode_impl) vi_synclist; /* s vnodes with dirty bufs */
94 SLIST_ENTRY(vnode_impl) vi_hash; /* c vnode cache list */
95 enum vnode_state vi_state; /* i current state */
96 TAILQ_ENTRY(vnode_impl) vi_mntvnodes; /* m vnodes for mount point */
97
98 /*
99 * Namecache. Give it a separate line so activity doesn't impinge
100 * on the stable stuff.
101 */
102 rb_tree_t vi_nc_tree /* n namecache tree */
103 __aligned(COHERENCY_UNIT);
104 TAILQ_HEAD(,namecache) vi_nc_list; /* l namecaches (parent) */
105 mode_t vi_nc_mode; /* n,l cached mode or VNOVAL */
106 uid_t vi_nc_uid; /* n,l cached UID or VNOVAL */
107 gid_t vi_nc_gid; /* n,l cached GID or VNOVAL */
108 uint32_t vi_nc_spare; /* - spare (padding) */
109
110 /*
111 * Locks and expensive to access items which can be expected to
112 * generate a cache miss.
113 */
114 krwlock_t vi_lock /* - lock for this vnode */
115 __aligned(COHERENCY_UNIT);
116 krwlock_t vi_nc_lock /* - lock on node */
117 __aligned(COHERENCY_UNIT);
118 krwlock_t vi_nc_listlock; /* - lock on nn_list */
119};
120typedef struct vnode_impl vnode_impl_t;
121
122#define VIMPL_TO_VNODE(vip) (&(vip)->vi_vnode)
123#define VNODE_TO_VIMPL(vp) container_of((vp), struct vnode_impl, vi_vnode)
124
125/*
126 * Vnode state assertion.
127 */
128void _vstate_assert(vnode_t *, enum vnode_state, const char *, int, bool);
129
130#if defined(DIAGNOSTIC)
131
132#define VSTATE_ASSERT(vp, state) \
133 _vstate_assert((vp), (state), __func__, __LINE__, true)
134#define VSTATE_ASSERT_UNLOCKED(vp, state) \
135 _vstate_assert((vp), (state), __func__, __LINE__, false)
136
137#else /* defined(DIAGNOSTIC) */
138
139#define VSTATE_ASSERT(vp, state)
140#define VSTATE_ASSERT_UNLOCKED(vp, state)
141
142#endif /* defined(DIAGNOSTIC) */
143
144/*
145 * Vnode manipulation functions.
146 */
147const char *
148 vstate_name(enum vnode_state);
149vnode_t *
150 vnalloc_marker(struct mount *);
151void vnfree_marker(vnode_t *);
152bool vnis_marker(vnode_t *);
153void vcache_make_anon(vnode_t *);
154int vcache_vget(vnode_t *);
155int vcache_tryvget(vnode_t *);
156int vfs_drainvnodes(void);
157
158#endif /* defined(_KERNEL) || defined(_KMEMUSER) */
159#endif /* !_SYS_VNODE_IMPL_H_ */