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, data block (for each of these we need bitmap + group 33 * summaries), root which is stored in the inode, sb 34 */ 35 36 #define EXT4_SINGLEDATA_TRANS_BLOCKS(sb) \ 37 (ext4_has_feature_extents(sb) ? 20U : 8U) 38 39 /* Extended attribute operations touch at most two data buffers, 40 * two bitmap buffers, and two group summaries, in addition to the inode 41 * and the superblock, which are already accounted for. */ 42 43 #define EXT4_XATTR_TRANS_BLOCKS 6U 44 45 /* Define the minimum size for a transaction which modifies data. This 46 * needs to take into account the fact that we may end up modifying two 47 * quota files too (one for the group, one for the user quota). The 48 * superblock only gets updated once, of course, so don't bother 49 * counting that again for the quota updates. */ 50 51 #define EXT4_DATA_TRANS_BLOCKS(sb) (EXT4_SINGLEDATA_TRANS_BLOCKS(sb) + \ 52 EXT4_XATTR_TRANS_BLOCKS - 2 + \ 53 EXT4_MAXQUOTAS_TRANS_BLOCKS(sb)) 54 55 /* 56 * Define the number of metadata blocks we need to account to modify data. 57 * 58 * This include super block, inode block, quota blocks and xattr blocks 59 */ 60 #define EXT4_META_TRANS_BLOCKS(sb) (EXT4_XATTR_TRANS_BLOCKS + \ 61 EXT4_MAXQUOTAS_TRANS_BLOCKS(sb)) 62 63 /* Define an arbitrary limit for the amount of data we will anticipate 64 * writing to any given transaction. For unbounded transactions such as 65 * write(2) and truncate(2) we can write more than this, but we always 66 * start off at the maximum transaction size and grow the transaction 67 * optimistically as we go. */ 68 69 #define EXT4_MAX_TRANS_DATA 64U 70 71 /* We break up a large truncate or write transaction once the handle's 72 * buffer credits gets this low, we need either to extend the 73 * transaction or to start a new one. Reserve enough space here for 74 * inode, bitmap, superblock, group and indirection updates for at least 75 * one block, plus two quota updates. Quota allocations are not 76 * needed. */ 77 78 #define EXT4_RESERVE_TRANS_BLOCKS 12U 79 80 /* 81 * Number of credits needed if we need to insert an entry into a 82 * directory. For each new index block, we need 4 blocks (old index 83 * block, new index block, bitmap block, bg summary). For normal 84 * htree directories there are 2 levels; if the largedir feature 85 * enabled it's 3 levels. 86 */ 87 #define EXT4_INDEX_EXTRA_TRANS_BLOCKS 12U 88 89 #ifdef CONFIG_QUOTA 90 /* Amount of blocks needed for quota update - we know that the structure was 91 * allocated so we need to update only data block */ 92 #define EXT4_QUOTA_TRANS_BLOCKS(sb) ((test_opt(sb, QUOTA) ||\ 93 ext4_has_feature_quota(sb)) ? 1 : 0) 94 /* Amount of blocks needed for quota insert/delete - we do some block writes 95 * but inode, sb and group updates are done only once */ 96 #define EXT4_QUOTA_INIT_BLOCKS(sb) ((test_opt(sb, QUOTA) ||\ 97 ext4_has_feature_quota(sb)) ?\ 98 (DQUOT_INIT_ALLOC*(EXT4_SINGLEDATA_TRANS_BLOCKS(sb)-3)\ 99 +3+DQUOT_INIT_REWRITE) : 0) 100 101 #define EXT4_QUOTA_DEL_BLOCKS(sb) ((test_opt(sb, QUOTA) ||\ 102 ext4_has_feature_quota(sb)) ?\ 103 (DQUOT_DEL_ALLOC*(EXT4_SINGLEDATA_TRANS_BLOCKS(sb)-3)\ 104 +3+DQUOT_DEL_REWRITE) : 0) 105 #else 106 #define EXT4_QUOTA_TRANS_BLOCKS(sb) 0 107 #define EXT4_QUOTA_INIT_BLOCKS(sb) 0 108 #define EXT4_QUOTA_DEL_BLOCKS(sb) 0 109 #endif 110 #define EXT4_MAXQUOTAS_TRANS_BLOCKS(sb) (EXT4_MAXQUOTAS*EXT4_QUOTA_TRANS_BLOCKS(sb)) 111 #define EXT4_MAXQUOTAS_INIT_BLOCKS(sb) (EXT4_MAXQUOTAS*EXT4_QUOTA_INIT_BLOCKS(sb)) 112 #define EXT4_MAXQUOTAS_DEL_BLOCKS(sb) (EXT4_MAXQUOTAS*EXT4_QUOTA_DEL_BLOCKS(sb)) 113 114 static inline int ext4_jbd2_credits_xattr(struct inode *inode) 115 { 116 int credits = EXT4_DATA_TRANS_BLOCKS(inode->i_sb); 117 118 /* 119 * In case of inline data, we may push out the data to a block, 120 * so we need to reserve credits for this eventuality 121 */ 122 if (ext4_has_inline_data(inode)) 123 credits += ext4_writepage_trans_blocks(inode) + 1; 124 return credits; 125 } 126 127 128 /* 129 * Ext4 handle operation types -- for logging purposes 130 */ 131 #define EXT4_HT_MISC 0 132 #define EXT4_HT_INODE 1 133 #define EXT4_HT_WRITE_PAGE 2 134 #define EXT4_HT_MAP_BLOCKS 3 135 #define EXT4_HT_DIR 4 136 #define EXT4_HT_TRUNCATE 5 137 #define EXT4_HT_QUOTA 6 138 #define EXT4_HT_RESIZE 7 139 #define EXT4_HT_MIGRATE 8 140 #define EXT4_HT_MOVE_EXTENTS 9 141 #define EXT4_HT_XATTR 10 142 #define EXT4_HT_EXT_CONVERT 11 143 #define EXT4_HT_MAX 12 144 145 /** 146 * struct ext4_journal_cb_entry - Base structure for callback information. 147 * 148 * This struct is a 'seed' structure for a using with your own callback 149 * structs. If you are using callbacks you must allocate one of these 150 * or another struct of your own definition which has this struct 151 * as it's first element and pass it to ext4_journal_callback_add(). 152 */ 153 struct ext4_journal_cb_entry { 154 /* list information for other callbacks attached to the same handle */ 155 struct list_head jce_list; 156 157 /* Function to call with this callback structure */ 158 void (*jce_func)(struct super_block *sb, 159 struct ext4_journal_cb_entry *jce, int error); 160 161 /* user data goes here */ 162 }; 163 164 /** 165 * ext4_journal_callback_add: add a function to call after transaction commit 166 * @handle: active journal transaction handle to register callback on 167 * @func: callback function to call after the transaction has committed: 168 * @sb: superblock of current filesystem for transaction 169 * @jce: returned journal callback data 170 * @rc: journal state at commit (0 = transaction committed properly) 171 * @jce: journal callback data (internal and function private data struct) 172 * 173 * The registered function will be called in the context of the journal thread 174 * after the transaction for which the handle was created has completed. 175 * 176 * No locks are held when the callback function is called, so it is safe to 177 * call blocking functions from within the callback, but the callback should 178 * not block or run for too long, or the filesystem will be blocked waiting for 179 * the next transaction to commit. No journaling functions can be used, or 180 * there is a risk of deadlock. 181 * 182 * There is no guaranteed calling order of multiple registered callbacks on 183 * the same transaction. 184 */ 185 static inline void _ext4_journal_callback_add(handle_t *handle, 186 struct ext4_journal_cb_entry *jce) 187 { 188 /* Add the jce to transaction's private list */ 189 list_add_tail(&jce->jce_list, &handle->h_transaction->t_private_list); 190 } 191 192 static inline void ext4_journal_callback_add(handle_t *handle, 193 void (*func)(struct super_block *sb, 194 struct ext4_journal_cb_entry *jce, 195 int rc), 196 struct ext4_journal_cb_entry *jce) 197 { 198 struct ext4_sb_info *sbi = 199 EXT4_SB(handle->h_transaction->t_journal->j_private); 200 201 /* Add the jce to transaction's private list */ 202 jce->jce_func = func; 203 spin_lock(&sbi->s_md_lock); 204 _ext4_journal_callback_add(handle, jce); 205 spin_unlock(&sbi->s_md_lock); 206 } 207 208 209 /** 210 * ext4_journal_callback_del: delete a registered callback 211 * @handle: active journal transaction handle on which callback was registered 212 * @jce: registered journal callback entry to unregister 213 * Return true if object was successfully removed 214 */ 215 static inline bool ext4_journal_callback_try_del(handle_t *handle, 216 struct ext4_journal_cb_entry *jce) 217 { 218 bool deleted; 219 struct ext4_sb_info *sbi = 220 EXT4_SB(handle->h_transaction->t_journal->j_private); 221 222 spin_lock(&sbi->s_md_lock); 223 deleted = !list_empty(&jce->jce_list); 224 list_del_init(&jce->jce_list); 225 spin_unlock(&sbi->s_md_lock); 226 return deleted; 227 } 228 229 int 230 ext4_mark_iloc_dirty(handle_t *handle, 231 struct inode *inode, 232 struct ext4_iloc *iloc); 233 234 /* 235 * On success, We end up with an outstanding reference count against 236 * iloc->bh. This _must_ be cleaned up later. 237 */ 238 239 int ext4_reserve_inode_write(handle_t *handle, struct inode *inode, 240 struct ext4_iloc *iloc); 241 242 int ext4_mark_inode_dirty(handle_t *handle, struct inode *inode); 243 244 /* 245 * Wrapper functions with which ext4 calls into JBD. 246 */ 247 int __ext4_journal_get_write_access(const char *where, unsigned int line, 248 handle_t *handle, struct buffer_head *bh); 249 250 int __ext4_forget(const char *where, unsigned int line, handle_t *handle, 251 int is_metadata, struct inode *inode, 252 struct buffer_head *bh, ext4_fsblk_t blocknr); 253 254 int __ext4_journal_get_create_access(const char *where, unsigned int line, 255 handle_t *handle, struct buffer_head *bh); 256 257 int __ext4_handle_dirty_metadata(const char *where, unsigned int line, 258 handle_t *handle, struct inode *inode, 259 struct buffer_head *bh); 260 261 int __ext4_handle_dirty_super(const char *where, unsigned int line, 262 handle_t *handle, struct super_block *sb); 263 264 #define ext4_journal_get_write_access(handle, bh) \ 265 __ext4_journal_get_write_access(__func__, __LINE__, (handle), (bh)) 266 #define ext4_forget(handle, is_metadata, inode, bh, block_nr) \ 267 __ext4_forget(__func__, __LINE__, (handle), (is_metadata), (inode), \ 268 (bh), (block_nr)) 269 #define ext4_journal_get_create_access(handle, bh) \ 270 __ext4_journal_get_create_access(__func__, __LINE__, (handle), (bh)) 271 #define ext4_handle_dirty_metadata(handle, inode, bh) \ 272 __ext4_handle_dirty_metadata(__func__, __LINE__, (handle), (inode), \ 273 (bh)) 274 #define ext4_handle_dirty_super(handle, sb) \ 275 __ext4_handle_dirty_super(__func__, __LINE__, (handle), (sb)) 276 277 handle_t *__ext4_journal_start_sb(struct super_block *sb, unsigned int line, 278 int type, int blocks, int rsv_blocks); 279 int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle); 280 281 #define EXT4_NOJOURNAL_MAX_REF_COUNT ((unsigned long) 4096) 282 283 /* Note: Do not use this for NULL handles. This is only to determine if 284 * a properly allocated handle is using a journal or not. */ 285 static inline int ext4_handle_valid(handle_t *handle) 286 { 287 if ((unsigned long)handle < EXT4_NOJOURNAL_MAX_REF_COUNT) 288 return 0; 289 return 1; 290 } 291 292 static inline void ext4_handle_sync(handle_t *handle) 293 { 294 if (ext4_handle_valid(handle)) 295 handle->h_sync = 1; 296 } 297 298 static inline int ext4_handle_is_aborted(handle_t *handle) 299 { 300 if (ext4_handle_valid(handle)) 301 return is_handle_aborted(handle); 302 return 0; 303 } 304 305 static inline int ext4_handle_has_enough_credits(handle_t *handle, int needed) 306 { 307 if (ext4_handle_valid(handle) && handle->h_buffer_credits < needed) 308 return 0; 309 return 1; 310 } 311 312 #define ext4_journal_start_sb(sb, type, nblocks) \ 313 __ext4_journal_start_sb((sb), __LINE__, (type), (nblocks), 0) 314 315 #define ext4_journal_start(inode, type, nblocks) \ 316 __ext4_journal_start((inode), __LINE__, (type), (nblocks), 0) 317 318 #define ext4_journal_start_with_reserve(inode, type, blocks, rsv_blocks) \ 319 __ext4_journal_start((inode), __LINE__, (type), (blocks), (rsv_blocks)) 320 321 static inline handle_t *__ext4_journal_start(struct inode *inode, 322 unsigned int line, int type, 323 int blocks, int rsv_blocks) 324 { 325 return __ext4_journal_start_sb(inode->i_sb, line, type, blocks, 326 rsv_blocks); 327 } 328 329 #define ext4_journal_stop(handle) \ 330 __ext4_journal_stop(__func__, __LINE__, (handle)) 331 332 #define ext4_journal_start_reserved(handle, type) \ 333 __ext4_journal_start_reserved((handle), __LINE__, (type)) 334 335 handle_t *__ext4_journal_start_reserved(handle_t *handle, unsigned int line, 336 int type); 337 338 static inline void ext4_journal_free_reserved(handle_t *handle) 339 { 340 if (ext4_handle_valid(handle)) 341 jbd2_journal_free_reserved(handle); 342 } 343 344 static inline handle_t *ext4_journal_current_handle(void) 345 { 346 return journal_current_handle(); 347 } 348 349 static inline int ext4_journal_extend(handle_t *handle, int nblocks) 350 { 351 if (ext4_handle_valid(handle)) 352 return jbd2_journal_extend(handle, nblocks); 353 return 0; 354 } 355 356 static inline int ext4_journal_restart(handle_t *handle, int nblocks) 357 { 358 if (ext4_handle_valid(handle)) 359 return jbd2_journal_restart(handle, nblocks); 360 return 0; 361 } 362 363 static inline int ext4_journal_blocks_per_page(struct inode *inode) 364 { 365 if (EXT4_JOURNAL(inode) != NULL) 366 return jbd2_journal_blocks_per_page(inode); 367 return 0; 368 } 369 370 static inline int ext4_journal_force_commit(journal_t *journal) 371 { 372 if (journal) 373 return jbd2_journal_force_commit(journal); 374 return 0; 375 } 376 377 static inline int ext4_jbd2_inode_add_write(handle_t *handle, 378 struct inode *inode) 379 { 380 if (ext4_handle_valid(handle)) 381 return jbd2_journal_inode_add_write(handle, 382 EXT4_I(inode)->jinode); 383 return 0; 384 } 385 386 static inline int ext4_jbd2_inode_add_wait(handle_t *handle, 387 struct inode *inode) 388 { 389 if (ext4_handle_valid(handle)) 390 return jbd2_journal_inode_add_wait(handle, 391 EXT4_I(inode)->jinode); 392 return 0; 393 } 394 395 static inline void ext4_update_inode_fsync_trans(handle_t *handle, 396 struct inode *inode, 397 int datasync) 398 { 399 struct ext4_inode_info *ei = EXT4_I(inode); 400 401 if (ext4_handle_valid(handle)) { 402 ei->i_sync_tid = handle->h_transaction->t_tid; 403 if (datasync) 404 ei->i_datasync_tid = handle->h_transaction->t_tid; 405 } 406 } 407 408 /* super.c */ 409 int ext4_force_commit(struct super_block *sb); 410 411 /* 412 * Ext4 inode journal modes 413 */ 414 #define EXT4_INODE_JOURNAL_DATA_MODE 0x01 /* journal data mode */ 415 #define EXT4_INODE_ORDERED_DATA_MODE 0x02 /* ordered data mode */ 416 #define EXT4_INODE_WRITEBACK_DATA_MODE 0x04 /* writeback data mode */ 417 418 static inline int ext4_inode_journal_mode(struct inode *inode) 419 { 420 if (EXT4_JOURNAL(inode) == NULL) 421 return EXT4_INODE_WRITEBACK_DATA_MODE; /* writeback */ 422 /* We do not support data journalling with delayed allocation */ 423 if (!S_ISREG(inode->i_mode) || 424 test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA || 425 (ext4_test_inode_flag(inode, EXT4_INODE_JOURNAL_DATA) && 426 !test_opt(inode->i_sb, DELALLOC))) { 427 /* We do not support data journalling for encrypted data */ 428 if (S_ISREG(inode->i_mode) && ext4_encrypted_inode(inode)) 429 return EXT4_INODE_ORDERED_DATA_MODE; /* ordered */ 430 return EXT4_INODE_JOURNAL_DATA_MODE; /* journal data */ 431 } 432 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) 433 return EXT4_INODE_ORDERED_DATA_MODE; /* ordered */ 434 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA) 435 return EXT4_INODE_WRITEBACK_DATA_MODE; /* writeback */ 436 BUG(); 437 } 438 439 static inline int ext4_should_journal_data(struct inode *inode) 440 { 441 return ext4_inode_journal_mode(inode) & EXT4_INODE_JOURNAL_DATA_MODE; 442 } 443 444 static inline int ext4_should_order_data(struct inode *inode) 445 { 446 return ext4_inode_journal_mode(inode) & EXT4_INODE_ORDERED_DATA_MODE; 447 } 448 449 static inline int ext4_should_writeback_data(struct inode *inode) 450 { 451 return ext4_inode_journal_mode(inode) & EXT4_INODE_WRITEBACK_DATA_MODE; 452 } 453 454 /* 455 * This function controls whether or not we should try to go down the 456 * dioread_nolock code paths, which makes it safe to avoid taking 457 * i_mutex for direct I/O reads. This only works for extent-based 458 * files, and it doesn't work if data journaling is enabled, since the 459 * dioread_nolock code uses b_private to pass information back to the 460 * I/O completion handler, and this conflicts with the jbd's use of 461 * b_private. 462 */ 463 static inline int ext4_should_dioread_nolock(struct inode *inode) 464 { 465 if (!test_opt(inode->i_sb, DIOREAD_NOLOCK)) 466 return 0; 467 if (!S_ISREG(inode->i_mode)) 468 return 0; 469 if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) 470 return 0; 471 if (ext4_should_journal_data(inode)) 472 return 0; 473 return 1; 474 } 475 476 #endif /* _EXT4_JBD2_H */ 477