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