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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * sysfile.c
4 *
5 * Initialize, read, write, etc. system files.
6 *
7 * Copyright (C) 2002, 2004 Oracle. All rights reserved.
8 */
9
10#include <linux/fs.h>
11#include <linux/types.h>
12#include <linux/highmem.h>
13
14#include <cluster/masklog.h>
15
16#include "ocfs2.h"
17
18#include "alloc.h"
19#include "dir.h"
20#include "inode.h"
21#include "journal.h"
22#include "sysfile.h"
23
24#include "buffer_head_io.h"
25
26static struct inode * _ocfs2_get_system_file_inode(struct ocfs2_super *osb,
27 int type,
28 u32 slot);
29
30#ifdef CONFIG_DEBUG_LOCK_ALLOC
31static struct lock_class_key ocfs2_sysfile_cluster_lock_key[NUM_SYSTEM_INODES];
32#endif
33
34static inline int is_global_system_inode(int type)
35{
36 return type >= OCFS2_FIRST_ONLINE_SYSTEM_INODE &&
37 type <= OCFS2_LAST_GLOBAL_SYSTEM_INODE;
38}
39
40static struct inode **get_local_system_inode(struct ocfs2_super *osb,
41 int type,
42 u32 slot)
43{
44 int index;
45 struct inode **local_system_inodes, **free = NULL;
46
47 BUG_ON(slot == OCFS2_INVALID_SLOT);
48 BUG_ON(type < OCFS2_FIRST_LOCAL_SYSTEM_INODE ||
49 type > OCFS2_LAST_LOCAL_SYSTEM_INODE);
50
51 spin_lock(&osb->osb_lock);
52 local_system_inodes = osb->local_system_inodes;
53 spin_unlock(&osb->osb_lock);
54
55 if (unlikely(!local_system_inodes)) {
56 local_system_inodes =
57 kzalloc(array3_size(sizeof(struct inode *),
58 NUM_LOCAL_SYSTEM_INODES,
59 osb->max_slots),
60 GFP_NOFS);
61 if (!local_system_inodes) {
62 mlog_errno(-ENOMEM);
63 /*
64 * return NULL here so that ocfs2_get_sytem_file_inodes
65 * will try to create an inode and use it. We will try
66 * to initialize local_system_inodes next time.
67 */
68 return NULL;
69 }
70
71 spin_lock(&osb->osb_lock);
72 if (osb->local_system_inodes) {
73 /* Someone has initialized it for us. */
74 free = local_system_inodes;
75 local_system_inodes = osb->local_system_inodes;
76 } else
77 osb->local_system_inodes = local_system_inodes;
78 spin_unlock(&osb->osb_lock);
79 kfree(free);
80 }
81
82 index = (slot * NUM_LOCAL_SYSTEM_INODES) +
83 (type - OCFS2_FIRST_LOCAL_SYSTEM_INODE);
84
85 return &local_system_inodes[index];
86}
87
88struct inode *ocfs2_get_system_file_inode(struct ocfs2_super *osb,
89 int type,
90 u32 slot)
91{
92 struct inode *inode = NULL;
93 struct inode **arr = NULL;
94
95 /* avoid the lookup if cached in local system file array */
96 if (is_global_system_inode(type)) {
97 arr = &(osb->global_system_inodes[type]);
98 } else
99 arr = get_local_system_inode(osb, type, slot);
100
101 if (arr && ((inode = *arr) != NULL)) {
102 /* get a ref in addition to the array ref */
103 inode = igrab(inode);
104 BUG_ON(!inode);
105
106 return inode;
107 }
108
109 /* this gets one ref thru iget */
110 inode = _ocfs2_get_system_file_inode(osb, type, slot);
111
112 /* add one more if putting into array for first time */
113 if (inode && arr && !*arr && !cmpxchg(&(*arr), NULL, inode)) {
114 inode = igrab(inode);
115 BUG_ON(!inode);
116 }
117 return inode;
118}
119
120static struct inode * _ocfs2_get_system_file_inode(struct ocfs2_super *osb,
121 int type,
122 u32 slot)
123{
124 char namebuf[40];
125 struct inode *inode = NULL;
126 u64 blkno;
127 int len, status = 0;
128
129 len = ocfs2_sprintf_system_inode_name(namebuf,
130 sizeof(namebuf),
131 type, slot);
132
133 status = ocfs2_lookup_ino_from_name(osb->sys_root_inode,
134 namebuf, len, &blkno);
135 if (status < 0) {
136 goto bail;
137 }
138
139 inode = ocfs2_iget(osb, blkno, OCFS2_FI_FLAG_SYSFILE, type);
140 if (IS_ERR(inode)) {
141 mlog_errno(PTR_ERR(inode));
142 inode = NULL;
143 goto bail;
144 }
145#ifdef CONFIG_DEBUG_LOCK_ALLOC
146 if (type == LOCAL_USER_QUOTA_SYSTEM_INODE ||
147 type == LOCAL_GROUP_QUOTA_SYSTEM_INODE ||
148 type == JOURNAL_SYSTEM_INODE) {
149 /* Ignore inode lock on these inodes as the lock does not
150 * really belong to any process and lockdep cannot handle
151 * that */
152 OCFS2_I(inode)->ip_inode_lockres.l_lockdep_map.key = NULL;
153 } else {
154 lockdep_init_map(&OCFS2_I(inode)->ip_inode_lockres.
155 l_lockdep_map,
156 ocfs2_system_inodes[type].si_name,
157 &ocfs2_sysfile_cluster_lock_key[type], 0);
158 }
159#endif
160bail:
161
162 return inode;
163}
164