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 | |
26 | static struct inode * _ocfs2_get_system_file_inode(struct ocfs2_super *osb, |
27 | int type, |
28 | u32 slot); |
29 | |
30 | #ifdef CONFIG_DEBUG_LOCK_ALLOC |
31 | static struct lock_class_key ocfs2_sysfile_cluster_lock_key[NUM_SYSTEM_INODES]; |
32 | #endif |
33 | |
34 | static 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 | |
40 | static 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(lock: &osb->osb_lock); |
52 | local_system_inodes = osb->local_system_inodes; |
53 | spin_unlock(lock: &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(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(lock: &osb->osb_lock); |
79 | kfree(objp: 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 | |
88 | struct 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 | mutex_lock(&osb->system_file_mutex); |
102 | if (arr && ((inode = *arr) != NULL)) { |
103 | /* get a ref in addition to the array ref */ |
104 | inode = igrab(inode); |
105 | mutex_unlock(lock: &osb->system_file_mutex); |
106 | BUG_ON(!inode); |
107 | |
108 | return inode; |
109 | } |
110 | |
111 | /* this gets one ref thru iget */ |
112 | inode = _ocfs2_get_system_file_inode(osb, type, slot); |
113 | |
114 | /* add one more if putting into array for first time */ |
115 | if (arr && inode) { |
116 | *arr = igrab(inode); |
117 | BUG_ON(!*arr); |
118 | } |
119 | mutex_unlock(lock: &osb->system_file_mutex); |
120 | return inode; |
121 | } |
122 | |
123 | static struct inode * _ocfs2_get_system_file_inode(struct ocfs2_super *osb, |
124 | int type, |
125 | u32 slot) |
126 | { |
127 | char namebuf[40]; |
128 | struct inode *inode = NULL; |
129 | u64 blkno; |
130 | int status = 0; |
131 | |
132 | ocfs2_sprintf_system_inode_name(buf: namebuf, |
133 | len: sizeof(namebuf), |
134 | type, slot); |
135 | |
136 | status = ocfs2_lookup_ino_from_name(dir: osb->sys_root_inode, name: namebuf, |
137 | strlen(namebuf), blkno: &blkno); |
138 | if (status < 0) { |
139 | goto bail; |
140 | } |
141 | |
142 | inode = ocfs2_iget(osb, feoff: blkno, OCFS2_FI_FLAG_SYSFILE, sysfile_type: type); |
143 | if (IS_ERR(ptr: inode)) { |
144 | mlog_errno(PTR_ERR(inode)); |
145 | inode = NULL; |
146 | goto bail; |
147 | } |
148 | #ifdef CONFIG_DEBUG_LOCK_ALLOC |
149 | if (type == LOCAL_USER_QUOTA_SYSTEM_INODE || |
150 | type == LOCAL_GROUP_QUOTA_SYSTEM_INODE || |
151 | type == JOURNAL_SYSTEM_INODE) { |
152 | /* Ignore inode lock on these inodes as the lock does not |
153 | * really belong to any process and lockdep cannot handle |
154 | * that */ |
155 | OCFS2_I(inode)->ip_inode_lockres.l_lockdep_map.key = NULL; |
156 | } else { |
157 | lockdep_init_map(lock: &OCFS2_I(inode)->ip_inode_lockres. |
158 | l_lockdep_map, |
159 | name: ocfs2_system_inodes[type].si_name, |
160 | key: &ocfs2_sysfile_cluster_lock_key[type], subclass: 0); |
161 | } |
162 | #endif |
163 | bail: |
164 | |
165 | return inode; |
166 | } |
167 | |
168 | |