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_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS) \ 38 ? 20U : 8U) 39 40 /* Extended attribute operations touch at most two data buffers, 41 * two bitmap buffers, and two group summaries, in addition to the inode 42 * and the superblock, which are already accounted for. */ 43 44 #define EXT4_XATTR_TRANS_BLOCKS 6U 45 46 /* Define the minimum size for a transaction which modifies data. This 47 * needs to take into account the fact that we may end up modifying two 48 * quota files too (one for the group, one for the user quota). The 49 * superblock only gets updated once, of course, so don't bother 50 * counting that again for the quota updates. */ 51 52 #define EXT4_DATA_TRANS_BLOCKS(sb) (EXT4_SINGLEDATA_TRANS_BLOCKS(sb) + \ 53 EXT4_XATTR_TRANS_BLOCKS - 2 + \ 54 EXT4_MAXQUOTAS_TRANS_BLOCKS(sb)) 55 56 /* 57 * Define the number of metadata blocks we need to account to modify data. 58 * 59 * This include super block, inode block, quota blocks and xattr blocks 60 */ 61 #define EXT4_META_TRANS_BLOCKS(sb) (EXT4_XATTR_TRANS_BLOCKS + \ 62 EXT4_MAXQUOTAS_TRANS_BLOCKS(sb)) 63 64 /* Define an arbitrary limit for the amount of data we will anticipate 65 * writing to any given transaction. For unbounded transactions such as 66 * write(2) and truncate(2) we can write more than this, but we always 67 * start off at the maximum transaction size and grow the transaction 68 * optimistically as we go. */ 69 70 #define EXT4_MAX_TRANS_DATA 64U 71 72 /* We break up a large truncate or write transaction once the handle's 73 * buffer credits gets this low, we need either to extend the 74 * transaction or to start a new one. Reserve enough space here for 75 * inode, bitmap, superblock, group and indirection updates for at least 76 * one block, plus two quota updates. Quota allocations are not 77 * needed. */ 78 79 #define EXT4_RESERVE_TRANS_BLOCKS 12U 80 81 #define EXT4_INDEX_EXTRA_TRANS_BLOCKS 8 82 83 #ifdef CONFIG_QUOTA 84 /* Amount of blocks needed for quota update - we know that the structure was 85 * allocated so we need to update only data block */ 86 #define EXT4_QUOTA_TRANS_BLOCKS(sb) ((test_opt(sb, QUOTA) ||\ 87 EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA)) ?\ 88 1 : 0) 89 /* Amount of blocks needed for quota insert/delete - we do some block writes 90 * but inode, sb and group updates are done only once */ 91 #define EXT4_QUOTA_INIT_BLOCKS(sb) ((test_opt(sb, QUOTA) ||\ 92 EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA)) ?\ 93 (DQUOT_INIT_ALLOC*(EXT4_SINGLEDATA_TRANS_BLOCKS(sb)-3)\ 94 +3+DQUOT_INIT_REWRITE) : 0) 95 96 #define EXT4_QUOTA_DEL_BLOCKS(sb) ((test_opt(sb, QUOTA) ||\ 97 EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA)) ?\ 98 (DQUOT_DEL_ALLOC*(EXT4_SINGLEDATA_TRANS_BLOCKS(sb)-3)\ 99 +3+DQUOT_DEL_REWRITE) : 0) 100 #else 101 #define EXT4_QUOTA_TRANS_BLOCKS(sb) 0 102 #define EXT4_QUOTA_INIT_BLOCKS(sb) 0 103 #define EXT4_QUOTA_DEL_BLOCKS(sb) 0 104 #endif 105 #define EXT4_MAXQUOTAS_TRANS_BLOCKS(sb) (EXT4_MAXQUOTAS*EXT4_QUOTA_TRANS_BLOCKS(sb)) 106 #define EXT4_MAXQUOTAS_INIT_BLOCKS(sb) (EXT4_MAXQUOTAS*EXT4_QUOTA_INIT_BLOCKS(sb)) 107 #define EXT4_MAXQUOTAS_DEL_BLOCKS(sb) (EXT4_MAXQUOTAS*EXT4_QUOTA_DEL_BLOCKS(sb)) 108 109 static inline int ext4_jbd2_credits_xattr(struct inode *inode) 110 { 111 int credits = EXT4_DATA_TRANS_BLOCKS(inode->i_sb); 112 113 /* 114 * In case of inline data, we may push out the data to a block, 115 * so we need to reserve credits for this eventuality 116 */ 117 if (ext4_has_inline_data(inode)) 118 credits += ext4_writepage_trans_blocks(inode) + 1; 119 return credits; 120 } 121 122 123 /* 124 * Ext4 handle operation types -- for logging purposes 125 */ 126 #define EXT4_HT_MISC 0 127 #define EXT4_HT_INODE 1 128 #define EXT4_HT_WRITE_PAGE 2 129 #define EXT4_HT_MAP_BLOCKS 3 130 #define EXT4_HT_DIR 4 131 #define EXT4_HT_TRUNCATE 5 132 #define EXT4_HT_QUOTA 6 133 #define EXT4_HT_RESIZE 7 134 #define EXT4_HT_MIGRATE 8 135 #define EXT4_HT_MOVE_EXTENTS 9 136 #define EXT4_HT_XATTR 10 137 #define EXT4_HT_EXT_CONVERT 11 138 #define EXT4_HT_MAX 12 139 140 /** 141 * struct ext4_journal_cb_entry - Base structure for callback information. 142 * 143 * This struct is a 'seed' structure for a using with your own callback 144 * structs. If you are using callbacks you must allocate one of these 145 * or another struct of your own definition which has this struct 146 * as it's first element and pass it to ext4_journal_callback_add(). 147 */ 148 struct ext4_journal_cb_entry { 149 /* list information for other callbacks attached to the same handle */ 150 struct list_head jce_list; 151 152 /* Function to call with this callback structure */ 153 void (*jce_func)(struct super_block *sb, 154 struct ext4_journal_cb_entry *jce, int error); 155 156 /* user data goes here */ 157 }; 158 159 /** 160 * ext4_journal_callback_add: add a function to call after transaction commit 161 * @handle: active journal transaction handle to register callback on 162 * @func: callback function to call after the transaction has committed: 163 * @sb: superblock of current filesystem for transaction 164 * @jce: returned journal callback data 165 * @rc: journal state at commit (0 = transaction committed properly) 166 * @jce: journal callback data (internal and function private data struct) 167 * 168 * The registered function will be called in the context of the journal thread 169 * after the transaction for which the handle was created has completed. 170 * 171 * No locks are held when the callback function is called, so it is safe to 172 * call blocking functions from within the callback, but the callback should 173 * not block or run for too long, or the filesystem will be blocked waiting for 174 * the next transaction to commit. No journaling functions can be used, or 175 * there is a risk of deadlock. 176 * 177 * There is no guaranteed calling order of multiple registered callbacks on 178 * the same transaction. 179 */ 180 static inline void ext4_journal_callback_add(handle_t *handle, 181 void (*func)(struct super_block *sb, 182 struct ext4_journal_cb_entry *jce, 183 int rc), 184 struct ext4_journal_cb_entry *jce) 185 { 186 struct ext4_sb_info *sbi = 187 EXT4_SB(handle->h_transaction->t_journal->j_private); 188 189 /* Add the jce to transaction's private list */ 190 jce->jce_func = func; 191 spin_lock(&sbi->s_md_lock); 192 list_add_tail(&jce->jce_list, &handle->h_transaction->t_private_list); 193 spin_unlock(&sbi->s_md_lock); 194 } 195 196 /** 197 * ext4_journal_callback_del: delete a registered callback 198 * @handle: active journal transaction handle on which callback was registered 199 * @jce: registered journal callback entry to unregister 200 * Return true if object was successfully removed 201 */ 202 static inline bool ext4_journal_callback_try_del(handle_t *handle, 203 struct ext4_journal_cb_entry *jce) 204 { 205 bool deleted; 206 struct ext4_sb_info *sbi = 207 EXT4_SB(handle->h_transaction->t_journal->j_private); 208 209 spin_lock(&sbi->s_md_lock); 210 deleted = !list_empty(&jce->jce_list); 211 list_del_init(&jce->jce_list); 212 spin_unlock(&sbi->s_md_lock); 213 return deleted; 214 } 215 216 int 217 ext4_mark_iloc_dirty(handle_t *handle, 218 struct inode *inode, 219 struct ext4_iloc *iloc); 220 221 /* 222 * On success, We end up with an outstanding reference count against 223 * iloc->bh. This _must_ be cleaned up later. 224 */ 225 226 int ext4_reserve_inode_write(handle_t *handle, struct inode *inode, 227 struct ext4_iloc *iloc); 228 229 int ext4_mark_inode_dirty(handle_t *handle, struct inode *inode); 230 231 /* 232 * Wrapper functions with which ext4 calls into JBD. 233 */ 234 int __ext4_journal_get_write_access(const char *where, unsigned int line, 235 handle_t *handle, struct buffer_head *bh); 236 237 int __ext4_forget(const char *where, unsigned int line, handle_t *handle, 238 int is_metadata, struct inode *inode, 239 struct buffer_head *bh, ext4_fsblk_t blocknr); 240 241 int __ext4_journal_get_create_access(const char *where, unsigned int line, 242 handle_t *handle, struct buffer_head *bh); 243 244 int __ext4_handle_dirty_metadata(const char *where, unsigned int line, 245 handle_t *handle, struct inode *inode, 246 struct buffer_head *bh); 247 248 int __ext4_handle_dirty_super(const char *where, unsigned int line, 249 handle_t *handle, struct super_block *sb); 250 251 #define ext4_journal_get_write_access(handle, bh) \ 252 __ext4_journal_get_write_access(__func__, __LINE__, (handle), (bh)) 253 #define ext4_forget(handle, is_metadata, inode, bh, block_nr) \ 254 __ext4_forget(__func__, __LINE__, (handle), (is_metadata), (inode), \ 255 (bh), (block_nr)) 256 #define ext4_journal_get_create_access(handle, bh) \ 257 __ext4_journal_get_create_access(__func__, __LINE__, (handle), (bh)) 258 #define ext4_handle_dirty_metadata(handle, inode, bh) \ 259 __ext4_handle_dirty_metadata(__func__, __LINE__, (handle), (inode), \ 260 (bh)) 261 #define ext4_handle_dirty_super(handle, sb) \ 262 __ext4_handle_dirty_super(__func__, __LINE__, (handle), (sb)) 263 264 handle_t *__ext4_journal_start_sb(struct super_block *sb, unsigned int line, 265 int type, int blocks, int rsv_blocks); 266 int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle); 267 268 #define EXT4_NOJOURNAL_MAX_REF_COUNT ((unsigned long) 4096) 269 270 /* Note: Do not use this for NULL handles. This is only to determine if 271 * a properly allocated handle is using a journal or not. */ 272 static inline int ext4_handle_valid(handle_t *handle) 273 { 274 if ((unsigned long)handle < EXT4_NOJOURNAL_MAX_REF_COUNT) 275 return 0; 276 return 1; 277 } 278 279 static inline void ext4_handle_sync(handle_t *handle) 280 { 281 if (ext4_handle_valid(handle)) 282 handle->h_sync = 1; 283 } 284 285 static inline int ext4_handle_is_aborted(handle_t *handle) 286 { 287 if (ext4_handle_valid(handle)) 288 return is_handle_aborted(handle); 289 return 0; 290 } 291 292 static inline int ext4_handle_has_enough_credits(handle_t *handle, int needed) 293 { 294 if (ext4_handle_valid(handle) && handle->h_buffer_credits < needed) 295 return 0; 296 return 1; 297 } 298 299 #define ext4_journal_start_sb(sb, type, nblocks) \ 300 __ext4_journal_start_sb((sb), __LINE__, (type), (nblocks), 0) 301 302 #define ext4_journal_start(inode, type, nblocks) \ 303 __ext4_journal_start((inode), __LINE__, (type), (nblocks), 0) 304 305 #define ext4_journal_start_with_reserve(inode, type, blocks, rsv_blocks) \ 306 __ext4_journal_start((inode), __LINE__, (type), (blocks), (rsv_blocks)) 307 308 static inline handle_t *__ext4_journal_start(struct inode *inode, 309 unsigned int line, int type, 310 int blocks, int rsv_blocks) 311 { 312 return __ext4_journal_start_sb(inode->i_sb, line, type, blocks, 313 rsv_blocks); 314 } 315 316 #define ext4_journal_stop(handle) \ 317 __ext4_journal_stop(__func__, __LINE__, (handle)) 318 319 #define ext4_journal_start_reserved(handle, type) \ 320 __ext4_journal_start_reserved((handle), __LINE__, (type)) 321 322 handle_t *__ext4_journal_start_reserved(handle_t *handle, unsigned int line, 323 int type); 324 325 static inline void ext4_journal_free_reserved(handle_t *handle) 326 { 327 if (ext4_handle_valid(handle)) 328 jbd2_journal_free_reserved(handle); 329 } 330 331 static inline handle_t *ext4_journal_current_handle(void) 332 { 333 return journal_current_handle(); 334 } 335 336 static inline int ext4_journal_extend(handle_t *handle, int nblocks) 337 { 338 if (ext4_handle_valid(handle)) 339 return jbd2_journal_extend(handle, nblocks); 340 return 0; 341 } 342 343 static inline int ext4_journal_restart(handle_t *handle, int nblocks) 344 { 345 if (ext4_handle_valid(handle)) 346 return jbd2_journal_restart(handle, nblocks); 347 return 0; 348 } 349 350 static inline int ext4_journal_blocks_per_page(struct inode *inode) 351 { 352 if (EXT4_JOURNAL(inode) != NULL) 353 return jbd2_journal_blocks_per_page(inode); 354 return 0; 355 } 356 357 static inline int ext4_journal_force_commit(journal_t *journal) 358 { 359 if (journal) 360 return jbd2_journal_force_commit(journal); 361 return 0; 362 } 363 364 static inline int ext4_jbd2_file_inode(handle_t *handle, struct inode *inode) 365 { 366 if (ext4_handle_valid(handle)) 367 return jbd2_journal_file_inode(handle, EXT4_I(inode)->jinode); 368 return 0; 369 } 370 371 static inline void ext4_update_inode_fsync_trans(handle_t *handle, 372 struct inode *inode, 373 int datasync) 374 { 375 struct ext4_inode_info *ei = EXT4_I(inode); 376 377 if (ext4_handle_valid(handle)) { 378 ei->i_sync_tid = handle->h_transaction->t_tid; 379 if (datasync) 380 ei->i_datasync_tid = handle->h_transaction->t_tid; 381 } 382 } 383 384 /* super.c */ 385 int ext4_force_commit(struct super_block *sb); 386 387 /* 388 * Ext4 inode journal modes 389 */ 390 #define EXT4_INODE_JOURNAL_DATA_MODE 0x01 /* journal data mode */ 391 #define EXT4_INODE_ORDERED_DATA_MODE 0x02 /* ordered data mode */ 392 #define EXT4_INODE_WRITEBACK_DATA_MODE 0x04 /* writeback data mode */ 393 394 static inline int ext4_inode_journal_mode(struct inode *inode) 395 { 396 if (EXT4_JOURNAL(inode) == NULL) 397 return EXT4_INODE_WRITEBACK_DATA_MODE; /* writeback */ 398 /* We do not support data journalling with delayed allocation */ 399 if (!S_ISREG(inode->i_mode) || 400 test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) 401 return EXT4_INODE_JOURNAL_DATA_MODE; /* journal data */ 402 if (ext4_test_inode_flag(inode, EXT4_INODE_JOURNAL_DATA) && 403 !test_opt(inode->i_sb, DELALLOC)) 404 return EXT4_INODE_JOURNAL_DATA_MODE; /* journal data */ 405 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) 406 return EXT4_INODE_ORDERED_DATA_MODE; /* ordered */ 407 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA) 408 return EXT4_INODE_WRITEBACK_DATA_MODE; /* writeback */ 409 else 410 BUG(); 411 } 412 413 static inline int ext4_should_journal_data(struct inode *inode) 414 { 415 return ext4_inode_journal_mode(inode) & EXT4_INODE_JOURNAL_DATA_MODE; 416 } 417 418 static inline int ext4_should_order_data(struct inode *inode) 419 { 420 return ext4_inode_journal_mode(inode) & EXT4_INODE_ORDERED_DATA_MODE; 421 } 422 423 static inline int ext4_should_writeback_data(struct inode *inode) 424 { 425 return ext4_inode_journal_mode(inode) & EXT4_INODE_WRITEBACK_DATA_MODE; 426 } 427 428 /* 429 * This function controls whether or not we should try to go down the 430 * dioread_nolock code paths, which makes it safe to avoid taking 431 * i_mutex for direct I/O reads. This only works for extent-based 432 * files, and it doesn't work if data journaling is enabled, since the 433 * dioread_nolock code uses b_private to pass information back to the 434 * I/O completion handler, and this conflicts with the jbd's use of 435 * b_private. 436 */ 437 static inline int ext4_should_dioread_nolock(struct inode *inode) 438 { 439 if (!test_opt(inode->i_sb, DIOREAD_NOLOCK)) 440 return 0; 441 if (!S_ISREG(inode->i_mode)) 442 return 0; 443 if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) 444 return 0; 445 if (ext4_should_journal_data(inode)) 446 return 0; 447 return 1; 448 } 449 450 #endif /* _EXT4_JBD2_H */ 451