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 EXT4_MAXQUOTAS_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 EXT4_MAXQUOTAS_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 96 #define EXT4_QUOTA_DEL_BLOCKS(sb) (test_opt(sb, QUOTA) ? (DQUOT_DEL_ALLOC*\ 97 (EXT4_SINGLEDATA_TRANS_BLOCKS(sb)-3)+3+DQUOT_DEL_REWRITE) : 0) 98 #else 99 #define EXT4_QUOTA_TRANS_BLOCKS(sb) 0 100 #define EXT4_QUOTA_INIT_BLOCKS(sb) 0 101 #define EXT4_QUOTA_DEL_BLOCKS(sb) 0 102 #endif 103 #define EXT4_MAXQUOTAS_TRANS_BLOCKS(sb) (MAXQUOTAS*EXT4_QUOTA_TRANS_BLOCKS(sb)) 104 #define EXT4_MAXQUOTAS_INIT_BLOCKS(sb) (MAXQUOTAS*EXT4_QUOTA_INIT_BLOCKS(sb)) 105 #define EXT4_MAXQUOTAS_DEL_BLOCKS(sb) (MAXQUOTAS*EXT4_QUOTA_DEL_BLOCKS(sb)) 106 107 int 108 ext4_mark_iloc_dirty(handle_t *handle, 109 struct inode *inode, 110 struct ext4_iloc *iloc); 111 112 /* 113 * On success, We end up with an outstanding reference count against 114 * iloc->bh. This _must_ be cleaned up later. 115 */ 116 117 int ext4_reserve_inode_write(handle_t *handle, struct inode *inode, 118 struct ext4_iloc *iloc); 119 120 int ext4_mark_inode_dirty(handle_t *handle, struct inode *inode); 121 122 /* 123 * Wrapper functions with which ext4 calls into JBD. 124 */ 125 void ext4_journal_abort_handle(const char *caller, unsigned int line, 126 const char *err_fn, 127 struct buffer_head *bh, handle_t *handle, int err); 128 129 int __ext4_journal_get_undo_access(const char *where, unsigned int line, 130 handle_t *handle, struct buffer_head *bh); 131 132 int __ext4_journal_get_write_access(const char *where, unsigned int line, 133 handle_t *handle, struct buffer_head *bh); 134 135 int __ext4_forget(const char *where, unsigned int line, handle_t *handle, 136 int is_metadata, struct inode *inode, 137 struct buffer_head *bh, ext4_fsblk_t blocknr); 138 139 int __ext4_journal_get_create_access(const char *where, unsigned int line, 140 handle_t *handle, struct buffer_head *bh); 141 142 int __ext4_handle_dirty_metadata(const char *where, unsigned int line, 143 handle_t *handle, struct inode *inode, 144 struct buffer_head *bh); 145 146 int __ext4_handle_dirty_super(const char *where, unsigned int line, 147 handle_t *handle, struct super_block *sb); 148 149 #define ext4_journal_get_undo_access(handle, bh) \ 150 __ext4_journal_get_undo_access(__func__, __LINE__, (handle), (bh)) 151 #define ext4_journal_get_write_access(handle, bh) \ 152 __ext4_journal_get_write_access(__func__, __LINE__, (handle), (bh)) 153 #define ext4_forget(handle, is_metadata, inode, bh, block_nr) \ 154 __ext4_forget(__func__, __LINE__, (handle), (is_metadata), (inode), \ 155 (bh), (block_nr)) 156 #define ext4_journal_get_create_access(handle, bh) \ 157 __ext4_journal_get_create_access(__func__, __LINE__, (handle), (bh)) 158 #define ext4_handle_dirty_metadata(handle, inode, bh) \ 159 __ext4_handle_dirty_metadata(__func__, __LINE__, (handle), (inode), \ 160 (bh)) 161 #define ext4_handle_dirty_super(handle, sb) \ 162 __ext4_handle_dirty_super(__func__, __LINE__, (handle), (sb)) 163 164 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks); 165 int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle); 166 167 #define EXT4_NOJOURNAL_MAX_REF_COUNT ((unsigned long) 4096) 168 169 /* Note: Do not use this for NULL handles. This is only to determine if 170 * a properly allocated handle is using a journal or not. */ 171 static inline int ext4_handle_valid(handle_t *handle) 172 { 173 if ((unsigned long)handle < EXT4_NOJOURNAL_MAX_REF_COUNT) 174 return 0; 175 return 1; 176 } 177 178 static inline void ext4_handle_sync(handle_t *handle) 179 { 180 if (ext4_handle_valid(handle)) 181 handle->h_sync = 1; 182 } 183 184 static inline void ext4_handle_release_buffer(handle_t *handle, 185 struct buffer_head *bh) 186 { 187 if (ext4_handle_valid(handle)) 188 jbd2_journal_release_buffer(handle, bh); 189 } 190 191 static inline int ext4_handle_is_aborted(handle_t *handle) 192 { 193 if (ext4_handle_valid(handle)) 194 return is_handle_aborted(handle); 195 return 0; 196 } 197 198 static inline int ext4_handle_has_enough_credits(handle_t *handle, int needed) 199 { 200 if (ext4_handle_valid(handle) && handle->h_buffer_credits < needed) 201 return 0; 202 return 1; 203 } 204 205 static inline void ext4_journal_release_buffer(handle_t *handle, 206 struct buffer_head *bh) 207 { 208 if (ext4_handle_valid(handle)) 209 jbd2_journal_release_buffer(handle, bh); 210 } 211 212 static inline handle_t *ext4_journal_start(struct inode *inode, int nblocks) 213 { 214 return ext4_journal_start_sb(inode->i_sb, nblocks); 215 } 216 217 #define ext4_journal_stop(handle) \ 218 __ext4_journal_stop(__func__, __LINE__, (handle)) 219 220 static inline handle_t *ext4_journal_current_handle(void) 221 { 222 return journal_current_handle(); 223 } 224 225 static inline int ext4_journal_extend(handle_t *handle, int nblocks) 226 { 227 if (ext4_handle_valid(handle)) 228 return jbd2_journal_extend(handle, nblocks); 229 return 0; 230 } 231 232 static inline int ext4_journal_restart(handle_t *handle, int nblocks) 233 { 234 if (ext4_handle_valid(handle)) 235 return jbd2_journal_restart(handle, nblocks); 236 return 0; 237 } 238 239 static inline int ext4_journal_blocks_per_page(struct inode *inode) 240 { 241 if (EXT4_JOURNAL(inode) != NULL) 242 return jbd2_journal_blocks_per_page(inode); 243 return 0; 244 } 245 246 static inline int ext4_journal_force_commit(journal_t *journal) 247 { 248 if (journal) 249 return jbd2_journal_force_commit(journal); 250 return 0; 251 } 252 253 static inline int ext4_jbd2_file_inode(handle_t *handle, struct inode *inode) 254 { 255 if (ext4_handle_valid(handle)) 256 return jbd2_journal_file_inode(handle, &EXT4_I(inode)->jinode); 257 return 0; 258 } 259 260 static inline void ext4_update_inode_fsync_trans(handle_t *handle, 261 struct inode *inode, 262 int datasync) 263 { 264 struct ext4_inode_info *ei = EXT4_I(inode); 265 266 if (ext4_handle_valid(handle)) { 267 ei->i_sync_tid = handle->h_transaction->t_tid; 268 if (datasync) 269 ei->i_datasync_tid = handle->h_transaction->t_tid; 270 } 271 } 272 273 /* super.c */ 274 int ext4_force_commit(struct super_block *sb); 275 276 static inline int ext4_should_journal_data(struct inode *inode) 277 { 278 if (EXT4_JOURNAL(inode) == NULL) 279 return 0; 280 if (!S_ISREG(inode->i_mode)) 281 return 1; 282 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) 283 return 1; 284 if (ext4_test_inode_flag(inode, EXT4_INODE_JOURNAL_DATA)) 285 return 1; 286 return 0; 287 } 288 289 static inline int ext4_should_order_data(struct inode *inode) 290 { 291 if (EXT4_JOURNAL(inode) == NULL) 292 return 0; 293 if (!S_ISREG(inode->i_mode)) 294 return 0; 295 if (ext4_test_inode_flag(inode, EXT4_INODE_JOURNAL_DATA)) 296 return 0; 297 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) 298 return 1; 299 return 0; 300 } 301 302 static inline int ext4_should_writeback_data(struct inode *inode) 303 { 304 if (!S_ISREG(inode->i_mode)) 305 return 0; 306 if (EXT4_JOURNAL(inode) == NULL) 307 return 1; 308 if (ext4_test_inode_flag(inode, EXT4_INODE_JOURNAL_DATA)) 309 return 0; 310 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA) 311 return 1; 312 return 0; 313 } 314 315 /* 316 * This function controls whether or not we should try to go down the 317 * dioread_nolock code paths, which makes it safe to avoid taking 318 * i_mutex for direct I/O reads. This only works for extent-based 319 * files, and it doesn't work if data journaling is enabled, since the 320 * dioread_nolock code uses b_private to pass information back to the 321 * I/O completion handler, and this conflicts with the jbd's use of 322 * b_private. 323 */ 324 static inline int ext4_should_dioread_nolock(struct inode *inode) 325 { 326 if (!test_opt(inode->i_sb, DIOREAD_NOLOCK)) 327 return 0; 328 if (!S_ISREG(inode->i_mode)) 329 return 0; 330 if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) 331 return 0; 332 if (ext4_should_journal_data(inode)) 333 return 0; 334 return 1; 335 } 336 337 #endif /* _EXT4_JBD2_H */ 338