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 #define EXT4_INDEX_EXTRA_TRANS_BLOCKS 8 81 82 #ifdef CONFIG_QUOTA 83 /* Amount of blocks needed for quota update - we know that the structure was 84 * allocated so we need to update only data block */ 85 #define EXT4_QUOTA_TRANS_BLOCKS(sb) ((test_opt(sb, QUOTA) ||\ 86 ext4_has_feature_quota(sb)) ? 1 : 0) 87 /* Amount of blocks needed for quota insert/delete - we do some block writes 88 * but inode, sb and group updates are done only once */ 89 #define EXT4_QUOTA_INIT_BLOCKS(sb) ((test_opt(sb, QUOTA) ||\ 90 ext4_has_feature_quota(sb)) ?\ 91 (DQUOT_INIT_ALLOC*(EXT4_SINGLEDATA_TRANS_BLOCKS(sb)-3)\ 92 +3+DQUOT_INIT_REWRITE) : 0) 93 94 #define EXT4_QUOTA_DEL_BLOCKS(sb) ((test_opt(sb, QUOTA) ||\ 95 ext4_has_feature_quota(sb)) ?\ 96 (DQUOT_DEL_ALLOC*(EXT4_SINGLEDATA_TRANS_BLOCKS(sb)-3)\ 97 +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) (EXT4_MAXQUOTAS*EXT4_QUOTA_TRANS_BLOCKS(sb)) 104 #define EXT4_MAXQUOTAS_INIT_BLOCKS(sb) (EXT4_MAXQUOTAS*EXT4_QUOTA_INIT_BLOCKS(sb)) 105 #define EXT4_MAXQUOTAS_DEL_BLOCKS(sb) (EXT4_MAXQUOTAS*EXT4_QUOTA_DEL_BLOCKS(sb)) 106 107 static inline int ext4_jbd2_credits_xattr(struct inode *inode) 108 { 109 int credits = EXT4_DATA_TRANS_BLOCKS(inode->i_sb); 110 111 /* 112 * In case of inline data, we may push out the data to a block, 113 * so we need to reserve credits for this eventuality 114 */ 115 if (ext4_has_inline_data(inode)) 116 credits += ext4_writepage_trans_blocks(inode) + 1; 117 return credits; 118 } 119 120 121 /* 122 * Ext4 handle operation types -- for logging purposes 123 */ 124 #define EXT4_HT_MISC 0 125 #define EXT4_HT_INODE 1 126 #define EXT4_HT_WRITE_PAGE 2 127 #define EXT4_HT_MAP_BLOCKS 3 128 #define EXT4_HT_DIR 4 129 #define EXT4_HT_TRUNCATE 5 130 #define EXT4_HT_QUOTA 6 131 #define EXT4_HT_RESIZE 7 132 #define EXT4_HT_MIGRATE 8 133 #define EXT4_HT_MOVE_EXTENTS 9 134 #define EXT4_HT_XATTR 10 135 #define EXT4_HT_EXT_CONVERT 11 136 #define EXT4_HT_MAX 12 137 138 /** 139 * struct ext4_journal_cb_entry - Base structure for callback information. 140 * 141 * This struct is a 'seed' structure for a using with your own callback 142 * structs. If you are using callbacks you must allocate one of these 143 * or another struct of your own definition which has this struct 144 * as it's first element and pass it to ext4_journal_callback_add(). 145 */ 146 struct ext4_journal_cb_entry { 147 /* list information for other callbacks attached to the same handle */ 148 struct list_head jce_list; 149 150 /* Function to call with this callback structure */ 151 void (*jce_func)(struct super_block *sb, 152 struct ext4_journal_cb_entry *jce, int error); 153 154 /* user data goes here */ 155 }; 156 157 /** 158 * ext4_journal_callback_add: add a function to call after transaction commit 159 * @handle: active journal transaction handle to register callback on 160 * @func: callback function to call after the transaction has committed: 161 * @sb: superblock of current filesystem for transaction 162 * @jce: returned journal callback data 163 * @rc: journal state at commit (0 = transaction committed properly) 164 * @jce: journal callback data (internal and function private data struct) 165 * 166 * The registered function will be called in the context of the journal thread 167 * after the transaction for which the handle was created has completed. 168 * 169 * No locks are held when the callback function is called, so it is safe to 170 * call blocking functions from within the callback, but the callback should 171 * not block or run for too long, or the filesystem will be blocked waiting for 172 * the next transaction to commit. No journaling functions can be used, or 173 * there is a risk of deadlock. 174 * 175 * There is no guaranteed calling order of multiple registered callbacks on 176 * the same transaction. 177 */ 178 static inline void ext4_journal_callback_add(handle_t *handle, 179 void (*func)(struct super_block *sb, 180 struct ext4_journal_cb_entry *jce, 181 int rc), 182 struct ext4_journal_cb_entry *jce) 183 { 184 struct ext4_sb_info *sbi = 185 EXT4_SB(handle->h_transaction->t_journal->j_private); 186 187 /* Add the jce to transaction's private list */ 188 jce->jce_func = func; 189 spin_lock(&sbi->s_md_lock); 190 list_add_tail(&jce->jce_list, &handle->h_transaction->t_private_list); 191 spin_unlock(&sbi->s_md_lock); 192 } 193 194 /** 195 * ext4_journal_callback_del: delete a registered callback 196 * @handle: active journal transaction handle on which callback was registered 197 * @jce: registered journal callback entry to unregister 198 * Return true if object was successfully removed 199 */ 200 static inline bool ext4_journal_callback_try_del(handle_t *handle, 201 struct ext4_journal_cb_entry *jce) 202 { 203 bool deleted; 204 struct ext4_sb_info *sbi = 205 EXT4_SB(handle->h_transaction->t_journal->j_private); 206 207 spin_lock(&sbi->s_md_lock); 208 deleted = !list_empty(&jce->jce_list); 209 list_del_init(&jce->jce_list); 210 spin_unlock(&sbi->s_md_lock); 211 return deleted; 212 } 213 214 int 215 ext4_mark_iloc_dirty(handle_t *handle, 216 struct inode *inode, 217 struct ext4_iloc *iloc); 218 219 /* 220 * On success, We end up with an outstanding reference count against 221 * iloc->bh. This _must_ be cleaned up later. 222 */ 223 224 int ext4_reserve_inode_write(handle_t *handle, struct inode *inode, 225 struct ext4_iloc *iloc); 226 227 int ext4_mark_inode_dirty(handle_t *handle, struct inode *inode); 228 229 /* 230 * Wrapper functions with which ext4 calls into JBD. 231 */ 232 int __ext4_journal_get_write_access(const char *where, unsigned int line, 233 handle_t *handle, struct buffer_head *bh); 234 235 int __ext4_forget(const char *where, unsigned int line, handle_t *handle, 236 int is_metadata, struct inode *inode, 237 struct buffer_head *bh, ext4_fsblk_t blocknr); 238 239 int __ext4_journal_get_create_access(const char *where, unsigned int line, 240 handle_t *handle, struct buffer_head *bh); 241 242 int __ext4_handle_dirty_metadata(const char *where, unsigned int line, 243 handle_t *handle, struct inode *inode, 244 struct buffer_head *bh); 245 246 int __ext4_handle_dirty_super(const char *where, unsigned int line, 247 handle_t *handle, struct super_block *sb); 248 249 #define ext4_journal_get_write_access(handle, bh) \ 250 __ext4_journal_get_write_access(__func__, __LINE__, (handle), (bh)) 251 #define ext4_forget(handle, is_metadata, inode, bh, block_nr) \ 252 __ext4_forget(__func__, __LINE__, (handle), (is_metadata), (inode), \ 253 (bh), (block_nr)) 254 #define ext4_journal_get_create_access(handle, bh) \ 255 __ext4_journal_get_create_access(__func__, __LINE__, (handle), (bh)) 256 #define ext4_handle_dirty_metadata(handle, inode, bh) \ 257 __ext4_handle_dirty_metadata(__func__, __LINE__, (handle), (inode), \ 258 (bh)) 259 #define ext4_handle_dirty_super(handle, sb) \ 260 __ext4_handle_dirty_super(__func__, __LINE__, (handle), (sb)) 261 262 handle_t *__ext4_journal_start_sb(struct super_block *sb, unsigned int line, 263 int type, int blocks, int rsv_blocks); 264 int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle); 265 266 #define EXT4_NOJOURNAL_MAX_REF_COUNT ((unsigned long) 4096) 267 268 /* Note: Do not use this for NULL handles. This is only to determine if 269 * a properly allocated handle is using a journal or not. */ 270 static inline int ext4_handle_valid(handle_t *handle) 271 { 272 if ((unsigned long)handle < EXT4_NOJOURNAL_MAX_REF_COUNT) 273 return 0; 274 return 1; 275 } 276 277 static inline void ext4_handle_sync(handle_t *handle) 278 { 279 if (ext4_handle_valid(handle)) 280 handle->h_sync = 1; 281 } 282 283 static inline int ext4_handle_is_aborted(handle_t *handle) 284 { 285 if (ext4_handle_valid(handle)) 286 return is_handle_aborted(handle); 287 return 0; 288 } 289 290 static inline int ext4_handle_has_enough_credits(handle_t *handle, int needed) 291 { 292 if (ext4_handle_valid(handle) && handle->h_buffer_credits < needed) 293 return 0; 294 return 1; 295 } 296 297 #define ext4_journal_start_sb(sb, type, nblocks) \ 298 __ext4_journal_start_sb((sb), __LINE__, (type), (nblocks), 0) 299 300 #define ext4_journal_start(inode, type, nblocks) \ 301 __ext4_journal_start((inode), __LINE__, (type), (nblocks), 0) 302 303 #define ext4_journal_start_with_reserve(inode, type, blocks, rsv_blocks) \ 304 __ext4_journal_start((inode), __LINE__, (type), (blocks), (rsv_blocks)) 305 306 static inline handle_t *__ext4_journal_start(struct inode *inode, 307 unsigned int line, int type, 308 int blocks, int rsv_blocks) 309 { 310 return __ext4_journal_start_sb(inode->i_sb, line, type, blocks, 311 rsv_blocks); 312 } 313 314 #define ext4_journal_stop(handle) \ 315 __ext4_journal_stop(__func__, __LINE__, (handle)) 316 317 #define ext4_journal_start_reserved(handle, type) \ 318 __ext4_journal_start_reserved((handle), __LINE__, (type)) 319 320 handle_t *__ext4_journal_start_reserved(handle_t *handle, unsigned int line, 321 int type); 322 323 static inline void ext4_journal_free_reserved(handle_t *handle) 324 { 325 if (ext4_handle_valid(handle)) 326 jbd2_journal_free_reserved(handle); 327 } 328 329 static inline handle_t *ext4_journal_current_handle(void) 330 { 331 return journal_current_handle(); 332 } 333 334 static inline int ext4_journal_extend(handle_t *handle, int nblocks) 335 { 336 if (ext4_handle_valid(handle)) 337 return jbd2_journal_extend(handle, nblocks); 338 return 0; 339 } 340 341 static inline int ext4_journal_restart(handle_t *handle, int nblocks) 342 { 343 if (ext4_handle_valid(handle)) 344 return jbd2_journal_restart(handle, nblocks); 345 return 0; 346 } 347 348 static inline int ext4_journal_blocks_per_page(struct inode *inode) 349 { 350 if (EXT4_JOURNAL(inode) != NULL) 351 return jbd2_journal_blocks_per_page(inode); 352 return 0; 353 } 354 355 static inline int ext4_journal_force_commit(journal_t *journal) 356 { 357 if (journal) 358 return jbd2_journal_force_commit(journal); 359 return 0; 360 } 361 362 static inline int ext4_jbd2_file_inode(handle_t *handle, struct inode *inode) 363 { 364 if (ext4_handle_valid(handle)) 365 return jbd2_journal_inode_add_write(handle, 366 EXT4_I(inode)->jinode); 367 return 0; 368 } 369 370 static inline void ext4_update_inode_fsync_trans(handle_t *handle, 371 struct inode *inode, 372 int datasync) 373 { 374 struct ext4_inode_info *ei = EXT4_I(inode); 375 376 if (ext4_handle_valid(handle)) { 377 ei->i_sync_tid = handle->h_transaction->t_tid; 378 if (datasync) 379 ei->i_datasync_tid = handle->h_transaction->t_tid; 380 } 381 } 382 383 /* super.c */ 384 int ext4_force_commit(struct super_block *sb); 385 386 /* 387 * Ext4 inode journal modes 388 */ 389 #define EXT4_INODE_JOURNAL_DATA_MODE 0x01 /* journal data mode */ 390 #define EXT4_INODE_ORDERED_DATA_MODE 0x02 /* ordered data mode */ 391 #define EXT4_INODE_WRITEBACK_DATA_MODE 0x04 /* writeback data mode */ 392 393 static inline int ext4_inode_journal_mode(struct inode *inode) 394 { 395 if (EXT4_JOURNAL(inode) == NULL) 396 return EXT4_INODE_WRITEBACK_DATA_MODE; /* writeback */ 397 /* We do not support data journalling with delayed allocation */ 398 if (!S_ISREG(inode->i_mode) || 399 test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) 400 return EXT4_INODE_JOURNAL_DATA_MODE; /* journal data */ 401 if (ext4_test_inode_flag(inode, EXT4_INODE_JOURNAL_DATA) && 402 !test_opt(inode->i_sb, DELALLOC)) 403 return EXT4_INODE_JOURNAL_DATA_MODE; /* journal data */ 404 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) 405 return EXT4_INODE_ORDERED_DATA_MODE; /* ordered */ 406 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA) 407 return EXT4_INODE_WRITEBACK_DATA_MODE; /* writeback */ 408 else 409 BUG(); 410 } 411 412 static inline int ext4_should_journal_data(struct inode *inode) 413 { 414 return ext4_inode_journal_mode(inode) & EXT4_INODE_JOURNAL_DATA_MODE; 415 } 416 417 static inline int ext4_should_order_data(struct inode *inode) 418 { 419 return ext4_inode_journal_mode(inode) & EXT4_INODE_ORDERED_DATA_MODE; 420 } 421 422 static inline int ext4_should_writeback_data(struct inode *inode) 423 { 424 return ext4_inode_journal_mode(inode) & EXT4_INODE_WRITEBACK_DATA_MODE; 425 } 426 427 /* 428 * This function controls whether or not we should try to go down the 429 * dioread_nolock code paths, which makes it safe to avoid taking 430 * i_mutex for direct I/O reads. This only works for extent-based 431 * files, and it doesn't work if data journaling is enabled, since the 432 * dioread_nolock code uses b_private to pass information back to the 433 * I/O completion handler, and this conflicts with the jbd's use of 434 * b_private. 435 */ 436 static inline int ext4_should_dioread_nolock(struct inode *inode) 437 { 438 if (!test_opt(inode->i_sb, DIOREAD_NOLOCK)) 439 return 0; 440 if (!S_ISREG(inode->i_mode)) 441 return 0; 442 if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) 443 return 0; 444 if (ext4_should_journal_data(inode)) 445 return 0; 446 return 1; 447 } 448 449 #endif /* _EXT4_JBD2_H */ 450