| 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(&osb->osb_lock); |
| 52 | local_system_inodes = osb->local_system_inodes; |
| 53 | spin_unlock(&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(&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(&osb->osb_lock); |
| 79 | kfree(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(&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(&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(namebuf, |
| 133 | sizeof(namebuf), |
| 134 | type, slot); |
| 135 | |
| 136 | status = ocfs2_lookup_ino_from_name(osb->sys_root_inode, namebuf, |
| 137 | strlen(namebuf), &blkno); |
| 138 | if (status < 0) { |
| 139 | goto bail; |
| 140 | } |
| 141 | |
| 142 | inode = ocfs2_iget(osb, blkno, OCFS2_FI_FLAG_SYSFILE, type); |
| 143 | if (IS_ERR(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(&OCFS2_I(inode)->ip_inode_lockres. |
| 158 | l_lockdep_map, |
| 159 | ocfs2_system_inodes[type].si_name, |
| 160 | &ocfs2_sysfile_cluster_lock_key[type], 0); |
| 161 | } |
| 162 | #endif |
| 163 | bail: |
| 164 | |
| 165 | return inode; |
| 166 | } |
| 167 | |