1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* -*- mode: c; c-basic-offset: 8; -*-
3 * vim: noexpandtab sw=8 ts=8 sts=0:
4 *
5 * sysfile.c
6 *
7 * Initialize, read, write, etc. system files.
8 *
9 * Copyright (C) 2002, 2004 Oracle. All rights reserved.
10 */
11
12 #include <linux/fs.h>
13 #include <linux/types.h>
14 #include <linux/highmem.h>
15
16 #include <cluster/masklog.h>
17
18 #include "ocfs2.h"
19
20 #include "alloc.h"
21 #include "dir.h"
22 #include "inode.h"
23 #include "journal.h"
24 #include "sysfile.h"
25
26 #include "buffer_head_io.h"
27
28 static struct inode * _ocfs2_get_system_file_inode(struct ocfs2_super *osb,
29 int type,
30 u32 slot);
31
32 #ifdef CONFIG_DEBUG_LOCK_ALLOC
33 static struct lock_class_key ocfs2_sysfile_cluster_lock_key[NUM_SYSTEM_INODES];
34 #endif
35
is_global_system_inode(int type)36 static inline int is_global_system_inode(int type)
37 {
38 return type >= OCFS2_FIRST_ONLINE_SYSTEM_INODE &&
39 type <= OCFS2_LAST_GLOBAL_SYSTEM_INODE;
40 }
41
get_local_system_inode(struct ocfs2_super * osb,int type,u32 slot)42 static struct inode **get_local_system_inode(struct ocfs2_super *osb,
43 int type,
44 u32 slot)
45 {
46 int index;
47 struct inode **local_system_inodes, **free = NULL;
48
49 BUG_ON(slot == OCFS2_INVALID_SLOT);
50 BUG_ON(type < OCFS2_FIRST_LOCAL_SYSTEM_INODE ||
51 type > OCFS2_LAST_LOCAL_SYSTEM_INODE);
52
53 spin_lock(&osb->osb_lock);
54 local_system_inodes = osb->local_system_inodes;
55 spin_unlock(&osb->osb_lock);
56
57 if (unlikely(!local_system_inodes)) {
58 local_system_inodes =
59 kzalloc(array3_size(sizeof(struct inode *),
60 NUM_LOCAL_SYSTEM_INODES,
61 osb->max_slots),
62 GFP_NOFS);
63 if (!local_system_inodes) {
64 mlog_errno(-ENOMEM);
65 /*
66 * return NULL here so that ocfs2_get_sytem_file_inodes
67 * will try to create an inode and use it. We will try
68 * to initialize local_system_inodes next time.
69 */
70 return NULL;
71 }
72
73 spin_lock(&osb->osb_lock);
74 if (osb->local_system_inodes) {
75 /* Someone has initialized it for us. */
76 free = local_system_inodes;
77 local_system_inodes = osb->local_system_inodes;
78 } else
79 osb->local_system_inodes = local_system_inodes;
80 spin_unlock(&osb->osb_lock);
81 kfree(free);
82 }
83
84 index = (slot * NUM_LOCAL_SYSTEM_INODES) +
85 (type - OCFS2_FIRST_LOCAL_SYSTEM_INODE);
86
87 return &local_system_inodes[index];
88 }
89
ocfs2_get_system_file_inode(struct ocfs2_super * osb,int type,u32 slot)90 struct inode *ocfs2_get_system_file_inode(struct ocfs2_super *osb,
91 int type,
92 u32 slot)
93 {
94 struct inode *inode = NULL;
95 struct inode **arr = NULL;
96
97 /* avoid the lookup if cached in local system file array */
98 if (is_global_system_inode(type)) {
99 arr = &(osb->global_system_inodes[type]);
100 } else
101 arr = get_local_system_inode(osb, type, slot);
102
103 mutex_lock(&osb->system_file_mutex);
104 if (arr && ((inode = *arr) != NULL)) {
105 /* get a ref in addition to the array ref */
106 inode = igrab(inode);
107 mutex_unlock(&osb->system_file_mutex);
108 BUG_ON(!inode);
109
110 return inode;
111 }
112
113 /* this gets one ref thru iget */
114 inode = _ocfs2_get_system_file_inode(osb, type, slot);
115
116 /* add one more if putting into array for first time */
117 if (arr && inode) {
118 *arr = igrab(inode);
119 BUG_ON(!*arr);
120 }
121 mutex_unlock(&osb->system_file_mutex);
122 return inode;
123 }
124
_ocfs2_get_system_file_inode(struct ocfs2_super * osb,int type,u32 slot)125 static struct inode * _ocfs2_get_system_file_inode(struct ocfs2_super *osb,
126 int type,
127 u32 slot)
128 {
129 char namebuf[40];
130 struct inode *inode = NULL;
131 u64 blkno;
132 int status = 0;
133
134 ocfs2_sprintf_system_inode_name(namebuf,
135 sizeof(namebuf),
136 type, slot);
137
138 status = ocfs2_lookup_ino_from_name(osb->sys_root_inode, namebuf,
139 strlen(namebuf), &blkno);
140 if (status < 0) {
141 goto bail;
142 }
143
144 inode = ocfs2_iget(osb, blkno, OCFS2_FI_FLAG_SYSFILE, type);
145 if (IS_ERR(inode)) {
146 mlog_errno(PTR_ERR(inode));
147 inode = NULL;
148 goto bail;
149 }
150 #ifdef CONFIG_DEBUG_LOCK_ALLOC
151 if (type == LOCAL_USER_QUOTA_SYSTEM_INODE ||
152 type == LOCAL_GROUP_QUOTA_SYSTEM_INODE ||
153 type == JOURNAL_SYSTEM_INODE) {
154 /* Ignore inode lock on these inodes as the lock does not
155 * really belong to any process and lockdep cannot handle
156 * that */
157 OCFS2_I(inode)->ip_inode_lockres.l_lockdep_map.key = NULL;
158 } else {
159 lockdep_init_map(&OCFS2_I(inode)->ip_inode_lockres.
160 l_lockdep_map,
161 ocfs2_system_inodes[type].si_name,
162 &ocfs2_sysfile_cluster_lock_key[type], 0);
163 }
164 #endif
165 bail:
166
167 return inode;
168 }
169
170