1 /* 2 * ext4_jbd2.h 3 * 4 * Written by Stephen C. Tweedie <sct@redhat.com>, 1999 5 * 6 * Copyright 1998--1999 Red Hat corp --- All Rights Reserved 7 * 8 * This file is part of the Linux kernel and is made available under 9 * the terms of the GNU General Public License, version 2, or at your 10 * option, any later version, incorporated herein by reference. 11 * 12 * Ext4-specific journaling extensions. 13 */ 14 15 #ifndef _EXT4_JBD2_H 16 #define _EXT4_JBD2_H 17 18 #include <linux/fs.h> 19 #include <linux/jbd2.h> 20 #include "ext4.h" 21 22 #define EXT4_JOURNAL(inode) (EXT4_SB((inode)->i_sb)->s_journal) 23 24 /* Define the number of blocks we need to account to a transaction to 25 * modify one block of data. 26 * 27 * We may have to touch one inode, one bitmap buffer, up to three 28 * indirection blocks, the group and superblock summaries, and the data 29 * block to complete the transaction. 30 * 31 * For extents-enabled fs we may have to allocate and modify up to 32 * 5 levels of tree + root which are stored in the inode. */ 33 34 #define EXT4_SINGLEDATA_TRANS_BLOCKS(sb) \ 35 (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS) \ 36 ? 27U : 8U) 37 38 /* Extended attribute operations touch at most two data buffers, 39 * two bitmap buffers, and two group summaries, in addition to the inode 40 * and the superblock, which are already accounted for. */ 41 42 #define EXT4_XATTR_TRANS_BLOCKS 6U 43 44 /* Define the minimum size for a transaction which modifies data. This 45 * needs to take into account the fact that we may end up modifying two 46 * quota files too (one for the group, one for the user quota). The 47 * superblock only gets updated once, of course, so don't bother 48 * counting that again for the quota updates. */ 49 50 #define EXT4_DATA_TRANS_BLOCKS(sb) (EXT4_SINGLEDATA_TRANS_BLOCKS(sb) + \ 51 EXT4_XATTR_TRANS_BLOCKS - 2 + \ 52 2*EXT4_QUOTA_TRANS_BLOCKS(sb)) 53 54 /* 55 * Define the number of metadata blocks we need to account to modify data. 56 * 57 * This include super block, inode block, quota blocks and xattr blocks 58 */ 59 #define EXT4_META_TRANS_BLOCKS(sb) (EXT4_XATTR_TRANS_BLOCKS + \ 60 2*EXT4_QUOTA_TRANS_BLOCKS(sb)) 61 62 /* Delete operations potentially hit one directory's namespace plus an 63 * entire inode, plus arbitrary amounts of bitmap/indirection data. Be 64 * generous. We can grow the delete transaction later if necessary. */ 65 66 #define EXT4_DELETE_TRANS_BLOCKS(sb) (2 * EXT4_DATA_TRANS_BLOCKS(sb) + 64) 67 68 /* Define an arbitrary limit for the amount of data we will anticipate 69 * writing to any given transaction. For unbounded transactions such as 70 * write(2) and truncate(2) we can write more than this, but we always 71 * start off at the maximum transaction size and grow the transaction 72 * optimistically as we go. */ 73 74 #define EXT4_MAX_TRANS_DATA 64U 75 76 /* We break up a large truncate or write transaction once the handle's 77 * buffer credits gets this low, we need either to extend the 78 * transaction or to start a new one. Reserve enough space here for 79 * inode, bitmap, superblock, group and indirection updates for at least 80 * one block, plus two quota updates. Quota allocations are not 81 * needed. */ 82 83 #define EXT4_RESERVE_TRANS_BLOCKS 12U 84 85 #define EXT4_INDEX_EXTRA_TRANS_BLOCKS 8 86 87 #ifdef CONFIG_QUOTA 88 /* Amount of blocks needed for quota update - we know that the structure was 89 * allocated so we need to update only inode+data */ 90 #define EXT4_QUOTA_TRANS_BLOCKS(sb) (test_opt(sb, QUOTA) ? 2 : 0) 91 /* Amount of blocks needed for quota insert/delete - we do some block writes 92 * but inode, sb and group updates are done only once */ 93 #define EXT4_QUOTA_INIT_BLOCKS(sb) (test_opt(sb, QUOTA) ? (DQUOT_INIT_ALLOC*\ 94 (EXT4_SINGLEDATA_TRANS_BLOCKS(sb)-3)+3+DQUOT_INIT_REWRITE) : 0) 95 #define EXT4_QUOTA_DEL_BLOCKS(sb) (test_opt(sb, QUOTA) ? (DQUOT_DEL_ALLOC*\ 96 (EXT4_SINGLEDATA_TRANS_BLOCKS(sb)-3)+3+DQUOT_DEL_REWRITE) : 0) 97 #else 98 #define EXT4_QUOTA_TRANS_BLOCKS(sb) 0 99 #define EXT4_QUOTA_INIT_BLOCKS(sb) 0 100 #define EXT4_QUOTA_DEL_BLOCKS(sb) 0 101 #endif 102 103 int 104 ext4_mark_iloc_dirty(handle_t *handle, 105 struct inode *inode, 106 struct ext4_iloc *iloc); 107 108 /* 109 * On success, We end up with an outstanding reference count against 110 * iloc->bh. This _must_ be cleaned up later. 111 */ 112 113 int ext4_reserve_inode_write(handle_t *handle, struct inode *inode, 114 struct ext4_iloc *iloc); 115 116 int ext4_mark_inode_dirty(handle_t *handle, struct inode *inode); 117 118 /* 119 * Wrapper functions with which ext4 calls into JBD. 120 */ 121 void ext4_journal_abort_handle(const char *caller, const char *err_fn, 122 struct buffer_head *bh, handle_t *handle, int err); 123 124 int __ext4_journal_get_undo_access(const char *where, handle_t *handle, 125 struct buffer_head *bh); 126 127 int __ext4_journal_get_write_access(const char *where, handle_t *handle, 128 struct buffer_head *bh); 129 130 /* When called with an invalid handle, this will still do a put on the BH */ 131 int __ext4_journal_forget(const char *where, handle_t *handle, 132 struct buffer_head *bh); 133 134 int __ext4_forget(const char *where, handle_t *handle, int is_metadata, 135 struct inode *inode, struct buffer_head *bh, 136 ext4_fsblk_t blocknr); 137 138 int __ext4_journal_get_create_access(const char *where, 139 handle_t *handle, struct buffer_head *bh); 140 141 int __ext4_handle_dirty_metadata(const char *where, handle_t *handle, 142 struct inode *inode, struct buffer_head *bh); 143 144 #define ext4_journal_get_undo_access(handle, bh) \ 145 __ext4_journal_get_undo_access(__func__, (handle), (bh)) 146 #define ext4_journal_get_write_access(handle, bh) \ 147 __ext4_journal_get_write_access(__func__, (handle), (bh)) 148 #define ext4_forget(handle, is_metadata, inode, bh, block_nr) \ 149 __ext4_forget(__func__, (handle), (is_metadata), (inode), (bh),\ 150 (block_nr)) 151 #define ext4_journal_get_create_access(handle, bh) \ 152 __ext4_journal_get_create_access(__func__, (handle), (bh)) 153 #define ext4_journal_forget(handle, bh) \ 154 __ext4_journal_forget(__func__, (handle), (bh)) 155 #define ext4_handle_dirty_metadata(handle, inode, bh) \ 156 __ext4_handle_dirty_metadata(__func__, (handle), (inode), (bh)) 157 158 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks); 159 int __ext4_journal_stop(const char *where, handle_t *handle); 160 161 #define EXT4_NOJOURNAL_MAX_REF_COUNT ((unsigned long) 4096) 162 163 /* Note: Do not use this for NULL handles. This is only to determine if 164 * a properly allocated handle is using a journal or not. */ 165 static inline int ext4_handle_valid(handle_t *handle) 166 { 167 if ((unsigned long)handle < EXT4_NOJOURNAL_MAX_REF_COUNT) 168 return 0; 169 return 1; 170 } 171 172 static inline void ext4_handle_sync(handle_t *handle) 173 { 174 if (ext4_handle_valid(handle)) 175 handle->h_sync = 1; 176 } 177 178 static inline void ext4_handle_release_buffer(handle_t *handle, 179 struct buffer_head *bh) 180 { 181 if (ext4_handle_valid(handle)) 182 jbd2_journal_release_buffer(handle, bh); 183 } 184 185 static inline int ext4_handle_is_aborted(handle_t *handle) 186 { 187 if (ext4_handle_valid(handle)) 188 return is_handle_aborted(handle); 189 return 0; 190 } 191 192 static inline int ext4_handle_has_enough_credits(handle_t *handle, int needed) 193 { 194 if (ext4_handle_valid(handle) && handle->h_buffer_credits < needed) 195 return 0; 196 return 1; 197 } 198 199 static inline void ext4_journal_release_buffer(handle_t *handle, 200 struct buffer_head *bh) 201 { 202 if (ext4_handle_valid(handle)) 203 jbd2_journal_release_buffer(handle, bh); 204 } 205 206 static inline handle_t *ext4_journal_start(struct inode *inode, int nblocks) 207 { 208 return ext4_journal_start_sb(inode->i_sb, nblocks); 209 } 210 211 #define ext4_journal_stop(handle) \ 212 __ext4_journal_stop(__func__, (handle)) 213 214 static inline handle_t *ext4_journal_current_handle(void) 215 { 216 return journal_current_handle(); 217 } 218 219 static inline int ext4_journal_extend(handle_t *handle, int nblocks) 220 { 221 if (ext4_handle_valid(handle)) 222 return jbd2_journal_extend(handle, nblocks); 223 return 0; 224 } 225 226 static inline int ext4_journal_restart(handle_t *handle, int nblocks) 227 { 228 if (ext4_handle_valid(handle)) 229 return jbd2_journal_restart(handle, nblocks); 230 return 0; 231 } 232 233 static inline int ext4_journal_blocks_per_page(struct inode *inode) 234 { 235 if (EXT4_JOURNAL(inode) != NULL) 236 return jbd2_journal_blocks_per_page(inode); 237 return 0; 238 } 239 240 static inline int ext4_journal_force_commit(journal_t *journal) 241 { 242 if (journal) 243 return jbd2_journal_force_commit(journal); 244 return 0; 245 } 246 247 static inline int ext4_jbd2_file_inode(handle_t *handle, struct inode *inode) 248 { 249 if (ext4_handle_valid(handle)) 250 return jbd2_journal_file_inode(handle, &EXT4_I(inode)->jinode); 251 return 0; 252 } 253 254 /* super.c */ 255 int ext4_force_commit(struct super_block *sb); 256 257 static inline int ext4_should_journal_data(struct inode *inode) 258 { 259 if (EXT4_JOURNAL(inode) == NULL) 260 return 0; 261 if (!S_ISREG(inode->i_mode)) 262 return 1; 263 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) 264 return 1; 265 if (EXT4_I(inode)->i_flags & EXT4_JOURNAL_DATA_FL) 266 return 1; 267 return 0; 268 } 269 270 static inline int ext4_should_order_data(struct inode *inode) 271 { 272 if (EXT4_JOURNAL(inode) == NULL) 273 return 0; 274 if (!S_ISREG(inode->i_mode)) 275 return 0; 276 if (EXT4_I(inode)->i_flags & EXT4_JOURNAL_DATA_FL) 277 return 0; 278 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) 279 return 1; 280 return 0; 281 } 282 283 static inline int ext4_should_writeback_data(struct inode *inode) 284 { 285 if (!S_ISREG(inode->i_mode)) 286 return 0; 287 if (EXT4_JOURNAL(inode) == NULL) 288 return 1; 289 if (EXT4_I(inode)->i_flags & EXT4_JOURNAL_DATA_FL) 290 return 0; 291 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA) 292 return 1; 293 return 0; 294 } 295 296 #endif /* _EXT4_JBD2_H */ 297