Mark Fasheh | ccd979b | 2005-12-15 14:31:24 -0800 | [diff] [blame^] | 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/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 | |
| 44 | static struct inode * _ocfs2_get_system_file_inode(struct ocfs2_super *osb, |
| 45 | int type, |
| 46 | u32 slot); |
| 47 | |
| 48 | static inline int is_global_system_inode(int type); |
| 49 | static inline int is_in_system_inode_array(struct ocfs2_super *osb, |
| 50 | int type, |
| 51 | u32 slot); |
| 52 | |
| 53 | static 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 | |
| 59 | static 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 | |
| 66 | struct 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 | |
| 98 | static 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 | } |
| 126 | bail: |
| 127 | if (dirent_bh) |
| 128 | brelse(dirent_bh); |
| 129 | return inode; |
| 130 | } |
| 131 | |