1 /* -*- 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/highmem.h> 29 30 #include <cluster/masklog.h> 31 32 #include "ocfs2.h" 33 34 #include "alloc.h" 35 #include "dir.h" 36 #include "inode.h" 37 #include "journal.h" 38 #include "sysfile.h" 39 40 #include "buffer_head_io.h" 41 42 static struct inode * _ocfs2_get_system_file_inode(struct ocfs2_super *osb, 43 int type, 44 u32 slot); 45 46 #ifdef CONFIG_DEBUG_LOCK_ALLOC 47 static struct lock_class_key ocfs2_sysfile_cluster_lock_key[NUM_SYSTEM_INODES]; 48 #endif 49 50 static inline int is_global_system_inode(int type) 51 { 52 return type >= OCFS2_FIRST_ONLINE_SYSTEM_INODE && 53 type <= OCFS2_LAST_GLOBAL_SYSTEM_INODE; 54 } 55 56 static struct inode **get_local_system_inode(struct ocfs2_super *osb, 57 int type, 58 u32 slot) 59 { 60 int index; 61 struct inode **local_system_inodes, **free = NULL; 62 63 BUG_ON(slot == OCFS2_INVALID_SLOT); 64 BUG_ON(type < OCFS2_FIRST_LOCAL_SYSTEM_INODE || 65 type > OCFS2_LAST_LOCAL_SYSTEM_INODE); 66 67 spin_lock(&osb->osb_lock); 68 local_system_inodes = osb->local_system_inodes; 69 spin_unlock(&osb->osb_lock); 70 71 if (unlikely(!local_system_inodes)) { 72 local_system_inodes = 73 kzalloc(array3_size(sizeof(struct inode *), 74 NUM_LOCAL_SYSTEM_INODES, 75 osb->max_slots), 76 GFP_NOFS); 77 if (!local_system_inodes) { 78 mlog_errno(-ENOMEM); 79 /* 80 * return NULL here so that ocfs2_get_sytem_file_inodes 81 * will try to create an inode and use it. We will try 82 * to initialize local_system_inodes next time. 83 */ 84 return NULL; 85 } 86 87 spin_lock(&osb->osb_lock); 88 if (osb->local_system_inodes) { 89 /* Someone has initialized it for us. */ 90 free = local_system_inodes; 91 local_system_inodes = osb->local_system_inodes; 92 } else 93 osb->local_system_inodes = local_system_inodes; 94 spin_unlock(&osb->osb_lock); 95 kfree(free); 96 } 97 98 index = (slot * NUM_LOCAL_SYSTEM_INODES) + 99 (type - OCFS2_FIRST_LOCAL_SYSTEM_INODE); 100 101 return &local_system_inodes[index]; 102 } 103 104 struct inode *ocfs2_get_system_file_inode(struct ocfs2_super *osb, 105 int type, 106 u32 slot) 107 { 108 struct inode *inode = NULL; 109 struct inode **arr = NULL; 110 111 /* avoid the lookup if cached in local system file array */ 112 if (is_global_system_inode(type)) { 113 arr = &(osb->global_system_inodes[type]); 114 } else 115 arr = get_local_system_inode(osb, type, slot); 116 117 mutex_lock(&osb->system_file_mutex); 118 if (arr && ((inode = *arr) != NULL)) { 119 /* get a ref in addition to the array ref */ 120 inode = igrab(inode); 121 mutex_unlock(&osb->system_file_mutex); 122 BUG_ON(!inode); 123 124 return inode; 125 } 126 127 /* this gets one ref thru iget */ 128 inode = _ocfs2_get_system_file_inode(osb, type, slot); 129 130 /* add one more if putting into array for first time */ 131 if (arr && inode) { 132 *arr = igrab(inode); 133 BUG_ON(!*arr); 134 } 135 mutex_unlock(&osb->system_file_mutex); 136 return inode; 137 } 138 139 static struct inode * _ocfs2_get_system_file_inode(struct ocfs2_super *osb, 140 int type, 141 u32 slot) 142 { 143 char namebuf[40]; 144 struct inode *inode = NULL; 145 u64 blkno; 146 int status = 0; 147 148 ocfs2_sprintf_system_inode_name(namebuf, 149 sizeof(namebuf), 150 type, slot); 151 152 status = ocfs2_lookup_ino_from_name(osb->sys_root_inode, namebuf, 153 strlen(namebuf), &blkno); 154 if (status < 0) { 155 goto bail; 156 } 157 158 inode = ocfs2_iget(osb, blkno, OCFS2_FI_FLAG_SYSFILE, type); 159 if (IS_ERR(inode)) { 160 mlog_errno(PTR_ERR(inode)); 161 inode = NULL; 162 goto bail; 163 } 164 #ifdef CONFIG_DEBUG_LOCK_ALLOC 165 if (type == LOCAL_USER_QUOTA_SYSTEM_INODE || 166 type == LOCAL_GROUP_QUOTA_SYSTEM_INODE || 167 type == JOURNAL_SYSTEM_INODE) { 168 /* Ignore inode lock on these inodes as the lock does not 169 * really belong to any process and lockdep cannot handle 170 * that */ 171 OCFS2_I(inode)->ip_inode_lockres.l_lockdep_map.key = NULL; 172 } else { 173 lockdep_init_map(&OCFS2_I(inode)->ip_inode_lockres. 174 l_lockdep_map, 175 ocfs2_system_inodes[type].si_name, 176 &ocfs2_sysfile_cluster_lock_key[type], 0); 177 } 178 #endif 179 bail: 180 181 return inode; 182 } 183 184