blob: 600a8bc5b54113454868fec31113a097394dd08a [file] [log] [blame]
Mark Fashehccd979b2005-12-15 14:31:24 -08001/* -*- mode: c; c-basic-offset: 8; -*-
2 * vim: noexpandtab sw=8 ts=8 sts=0:
3 *
4 * sysfile.c
5 *
6 * Initialize, read, write, etc. system files.
7 *
8 * Copyright (C) 2002, 2004 Oracle. All rights reserved.
9 *
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public
12 * License as published by the Free Software Foundation; either
13 * version 2 of the License, or (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 * General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public
21 * License along with this program; if not, write to the
22 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
23 * Boston, MA 021110-1307, USA.
24 */
25
26#include <linux/fs.h>
27#include <linux/types.h>
28#include <linux/slab.h>
29#include <linux/highmem.h>
30
31#include "ocfs2.h"
32
33#define MLOG_MASK_PREFIX ML_INODE
34#include <cluster/masklog.h>
35
36#include "alloc.h"
37#include "dir.h"
38#include "inode.h"
39#include "journal.h"
40#include "sysfile.h"
41
42#include "buffer_head_io.h"
43
44static struct inode * _ocfs2_get_system_file_inode(struct ocfs2_super *osb,
45 int type,
46 u32 slot);
47
48static inline int is_global_system_inode(int type);
49static inline int is_in_system_inode_array(struct ocfs2_super *osb,
50 int type,
51 u32 slot);
52
53static inline int is_global_system_inode(int type)
54{
55 return type >= OCFS2_FIRST_ONLINE_SYSTEM_INODE &&
56 type <= OCFS2_LAST_GLOBAL_SYSTEM_INODE;
57}
58
59static inline int is_in_system_inode_array(struct ocfs2_super *osb,
60 int type,
61 u32 slot)
62{
63 return slot == osb->slot_num || is_global_system_inode(type);
64}
65
66struct inode *ocfs2_get_system_file_inode(struct ocfs2_super *osb,
67 int type,
68 u32 slot)
69{
70 struct inode *inode = NULL;
71 struct inode **arr = NULL;
72
73 /* avoid the lookup if cached in local system file array */
74 if (is_in_system_inode_array(osb, type, slot))
75 arr = &(osb->system_inodes[type]);
76
77 if (arr && ((inode = *arr) != NULL)) {
78 /* get a ref in addition to the array ref */
79 inode = igrab(inode);
80 if (!inode)
81 BUG();
82
83 return inode;
84 }
85
86 /* this gets one ref thru iget */
87 inode = _ocfs2_get_system_file_inode(osb, type, slot);
88
89 /* add one more if putting into array for first time */
90 if (arr && inode) {
91 *arr = igrab(inode);
92 if (!*arr)
93 BUG();
94 }
95 return inode;
96}
97
98static struct inode * _ocfs2_get_system_file_inode(struct ocfs2_super *osb,
99 int type,
100 u32 slot)
101{
102 char namebuf[40];
103 struct inode *inode = NULL;
104 u64 blkno;
105 struct buffer_head *dirent_bh = NULL;
106 struct ocfs2_dir_entry *de = NULL;
107 int status = 0;
108
109 ocfs2_sprintf_system_inode_name(namebuf,
110 sizeof(namebuf),
111 type, slot);
112
113 status = ocfs2_find_files_on_disk(namebuf, strlen(namebuf),
114 &blkno, osb->sys_root_inode,
115 &dirent_bh, &de);
116 if (status < 0) {
117 goto bail;
118 }
119
120 inode = ocfs2_iget(osb, blkno);
121 if (IS_ERR(inode)) {
122 mlog_errno(PTR_ERR(inode));
123 inode = NULL;
124 goto bail;
125 }
126bail:
127 if (dirent_bh)
128 brelse(dirent_bh);
129 return inode;
130}
131