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 /* Define an arbitrary limit for the amount of data we will anticipate 63 * writing to any given transaction. For unbounded transactions such as 64 * write(2) and truncate(2) we can write more than this, but we always 65 * start off at the maximum transaction size and grow the transaction 66 * optimistically as we go. */ 67 68 #define EXT4_MAX_TRANS_DATA 64U 69 70 /* We break up a large truncate or write transaction once the handle's 71 * buffer credits gets this low, we need either to extend the 72 * transaction or to start a new one. Reserve enough space here for 73 * inode, bitmap, superblock, group and indirection updates for at least 74 * one block, plus two quota updates. Quota allocations are not 75 * needed. */ 76 77 #define EXT4_RESERVE_TRANS_BLOCKS 12U 78 79 #define EXT4_INDEX_EXTRA_TRANS_BLOCKS 8 80 81 #ifdef CONFIG_QUOTA 82 /* Amount of blocks needed for quota update - we know that the structure was 83 * allocated so we need to update only data block */ 84 #define EXT4_QUOTA_TRANS_BLOCKS(sb) ((test_opt(sb, QUOTA) ||\ 85 EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA)) ?\ 86 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_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA)) ?\ 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_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA)) ?\ 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) (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 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_MAX 11 136 137 /** 138 * struct ext4_journal_cb_entry - Base structure for callback information. 139 * 140 * This struct is a 'seed' structure for a using with your own callback 141 * structs. If you are using callbacks you must allocate one of these 142 * or another struct of your own definition which has this struct 143 * as it's first element and pass it to ext4_journal_callback_add(). 144 */ 145 struct ext4_journal_cb_entry { 146 /* list information for other callbacks attached to the same handle */ 147 struct list_head jce_list; 148 149 /* Function to call with this callback structure */ 150 void (*jce_func)(struct super_block *sb, 151 struct ext4_journal_cb_entry *jce, int error); 152 153 /* user data goes here */ 154 }; 155 156 /** 157 * ext4_journal_callback_add: add a function to call after transaction commit 158 * @handle: active journal transaction handle to register callback on 159 * @func: callback function to call after the transaction has committed: 160 * @sb: superblock of current filesystem for transaction 161 * @jce: returned journal callback data 162 * @rc: journal state at commit (0 = transaction committed properly) 163 * @jce: journal callback data (internal and function private data struct) 164 * 165 * The registered function will be called in the context of the journal thread 166 * after the transaction for which the handle was created has completed. 167 * 168 * No locks are held when the callback function is called, so it is safe to 169 * call blocking functions from within the callback, but the callback should 170 * not block or run for too long, or the filesystem will be blocked waiting for 171 * the next transaction to commit. No journaling functions can be used, or 172 * there is a risk of deadlock. 173 * 174 * There is no guaranteed calling order of multiple registered callbacks on 175 * the same transaction. 176 */ 177 static inline void ext4_journal_callback_add(handle_t *handle, 178 void (*func)(struct super_block *sb, 179 struct ext4_journal_cb_entry *jce, 180 int rc), 181 struct ext4_journal_cb_entry *jce) 182 { 183 struct ext4_sb_info *sbi = 184 EXT4_SB(handle->h_transaction->t_journal->j_private); 185 186 /* Add the jce to transaction's private list */ 187 jce->jce_func = func; 188 spin_lock(&sbi->s_md_lock); 189 list_add_tail(&jce->jce_list, &handle->h_transaction->t_private_list); 190 spin_unlock(&sbi->s_md_lock); 191 } 192 193 /** 194 * ext4_journal_callback_del: delete a registered callback 195 * @handle: active journal transaction handle on which callback was registered 196 * @jce: registered journal callback entry to unregister 197 */ 198 static inline void ext4_journal_callback_del(handle_t *handle, 199 struct ext4_journal_cb_entry *jce) 200 { 201 struct ext4_sb_info *sbi = 202 EXT4_SB(handle->h_transaction->t_journal->j_private); 203 204 spin_lock(&sbi->s_md_lock); 205 list_del_init(&jce->jce_list); 206 spin_unlock(&sbi->s_md_lock); 207 } 208 209 int 210 ext4_mark_iloc_dirty(handle_t *handle, 211 struct inode *inode, 212 struct ext4_iloc *iloc); 213 214 /* 215 * On success, We end up with an outstanding reference count against 216 * iloc->bh. This _must_ be cleaned up later. 217 */ 218 219 int ext4_reserve_inode_write(handle_t *handle, struct inode *inode, 220 struct ext4_iloc *iloc); 221 222 int ext4_mark_inode_dirty(handle_t *handle, struct inode *inode); 223 224 /* 225 * Wrapper functions with which ext4 calls into JBD. 226 */ 227 void ext4_journal_abort_handle(const char *caller, unsigned int line, 228 const char *err_fn, 229 struct buffer_head *bh, handle_t *handle, int err); 230 231 int __ext4_journal_get_write_access(const char *where, unsigned int line, 232 handle_t *handle, struct buffer_head *bh); 233 234 int __ext4_forget(const char *where, unsigned int line, handle_t *handle, 235 int is_metadata, struct inode *inode, 236 struct buffer_head *bh, ext4_fsblk_t blocknr); 237 238 int __ext4_journal_get_create_access(const char *where, unsigned int line, 239 handle_t *handle, struct buffer_head *bh); 240 241 int __ext4_handle_dirty_metadata(const char *where, unsigned int line, 242 handle_t *handle, struct inode *inode, 243 struct buffer_head *bh); 244 245 int __ext4_handle_dirty_super(const char *where, unsigned int line, 246 handle_t *handle, struct super_block *sb); 247 248 #define ext4_journal_get_write_access(handle, bh) \ 249 __ext4_journal_get_write_access(__func__, __LINE__, (handle), (bh)) 250 #define ext4_forget(handle, is_metadata, inode, bh, block_nr) \ 251 __ext4_forget(__func__, __LINE__, (handle), (is_metadata), (inode), \ 252 (bh), (block_nr)) 253 #define ext4_journal_get_create_access(handle, bh) \ 254 __ext4_journal_get_create_access(__func__, __LINE__, (handle), (bh)) 255 #define ext4_handle_dirty_metadata(handle, inode, bh) \ 256 __ext4_handle_dirty_metadata(__func__, __LINE__, (handle), (inode), \ 257 (bh)) 258 #define ext4_handle_dirty_super(handle, sb) \ 259 __ext4_handle_dirty_super(__func__, __LINE__, (handle), (sb)) 260 261 handle_t *__ext4_journal_start_sb(struct super_block *sb, unsigned int line, 262 int type, int nblocks); 263 int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle); 264 265 #define EXT4_NOJOURNAL_MAX_REF_COUNT ((unsigned long) 4096) 266 267 /* Note: Do not use this for NULL handles. This is only to determine if 268 * a properly allocated handle is using a journal or not. */ 269 static inline int ext4_handle_valid(handle_t *handle) 270 { 271 if ((unsigned long)handle < EXT4_NOJOURNAL_MAX_REF_COUNT) 272 return 0; 273 return 1; 274 } 275 276 static inline void ext4_handle_sync(handle_t *handle) 277 { 278 if (ext4_handle_valid(handle)) 279 handle->h_sync = 1; 280 } 281 282 static inline int ext4_handle_is_aborted(handle_t *handle) 283 { 284 if (ext4_handle_valid(handle)) 285 return is_handle_aborted(handle); 286 return 0; 287 } 288 289 static inline int ext4_handle_has_enough_credits(handle_t *handle, int needed) 290 { 291 if (ext4_handle_valid(handle) && handle->h_buffer_credits < needed) 292 return 0; 293 return 1; 294 } 295 296 #define ext4_journal_start_sb(sb, type, nblocks) \ 297 __ext4_journal_start_sb((sb), __LINE__, (type), (nblocks)) 298 299 #define ext4_journal_start(inode, type, nblocks) \ 300 __ext4_journal_start((inode), __LINE__, (type), (nblocks)) 301 302 static inline handle_t *__ext4_journal_start(struct inode *inode, 303 unsigned int line, int type, 304 int nblocks) 305 { 306 return __ext4_journal_start_sb(inode->i_sb, line, type, nblocks); 307 } 308 309 #define ext4_journal_stop(handle) \ 310 __ext4_journal_stop(__func__, __LINE__, (handle)) 311 312 static inline handle_t *ext4_journal_current_handle(void) 313 { 314 return journal_current_handle(); 315 } 316 317 static inline int ext4_journal_extend(handle_t *handle, int nblocks) 318 { 319 if (ext4_handle_valid(handle)) 320 return jbd2_journal_extend(handle, nblocks); 321 return 0; 322 } 323 324 static inline int ext4_journal_restart(handle_t *handle, int nblocks) 325 { 326 if (ext4_handle_valid(handle)) 327 return jbd2_journal_restart(handle, nblocks); 328 return 0; 329 } 330 331 static inline int ext4_journal_blocks_per_page(struct inode *inode) 332 { 333 if (EXT4_JOURNAL(inode) != NULL) 334 return jbd2_journal_blocks_per_page(inode); 335 return 0; 336 } 337 338 static inline int ext4_journal_force_commit(journal_t *journal) 339 { 340 if (journal) 341 return jbd2_journal_force_commit(journal); 342 return 0; 343 } 344 345 static inline int ext4_jbd2_file_inode(handle_t *handle, struct inode *inode) 346 { 347 if (ext4_handle_valid(handle)) 348 return jbd2_journal_file_inode(handle, EXT4_I(inode)->jinode); 349 return 0; 350 } 351 352 static inline void ext4_update_inode_fsync_trans(handle_t *handle, 353 struct inode *inode, 354 int datasync) 355 { 356 struct ext4_inode_info *ei = EXT4_I(inode); 357 358 if (ext4_handle_valid(handle)) { 359 ei->i_sync_tid = handle->h_transaction->t_tid; 360 if (datasync) 361 ei->i_datasync_tid = handle->h_transaction->t_tid; 362 } 363 } 364 365 /* super.c */ 366 int ext4_force_commit(struct super_block *sb); 367 368 /* 369 * Ext4 inode journal modes 370 */ 371 #define EXT4_INODE_JOURNAL_DATA_MODE 0x01 /* journal data mode */ 372 #define EXT4_INODE_ORDERED_DATA_MODE 0x02 /* ordered data mode */ 373 #define EXT4_INODE_WRITEBACK_DATA_MODE 0x04 /* writeback data mode */ 374 375 static inline int ext4_inode_journal_mode(struct inode *inode) 376 { 377 if (EXT4_JOURNAL(inode) == NULL) 378 return EXT4_INODE_WRITEBACK_DATA_MODE; /* writeback */ 379 /* We do not support data journalling with delayed allocation */ 380 if (!S_ISREG(inode->i_mode) || 381 test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) 382 return EXT4_INODE_JOURNAL_DATA_MODE; /* journal data */ 383 if (ext4_test_inode_flag(inode, EXT4_INODE_JOURNAL_DATA) && 384 !test_opt(inode->i_sb, DELALLOC)) 385 return EXT4_INODE_JOURNAL_DATA_MODE; /* journal data */ 386 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) 387 return EXT4_INODE_ORDERED_DATA_MODE; /* ordered */ 388 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA) 389 return EXT4_INODE_WRITEBACK_DATA_MODE; /* writeback */ 390 else 391 BUG(); 392 } 393 394 static inline int ext4_should_journal_data(struct inode *inode) 395 { 396 return ext4_inode_journal_mode(inode) & EXT4_INODE_JOURNAL_DATA_MODE; 397 } 398 399 static inline int ext4_should_order_data(struct inode *inode) 400 { 401 return ext4_inode_journal_mode(inode) & EXT4_INODE_ORDERED_DATA_MODE; 402 } 403 404 static inline int ext4_should_writeback_data(struct inode *inode) 405 { 406 return ext4_inode_journal_mode(inode) & EXT4_INODE_WRITEBACK_DATA_MODE; 407 } 408 409 /* 410 * This function controls whether or not we should try to go down the 411 * dioread_nolock code paths, which makes it safe to avoid taking 412 * i_mutex for direct I/O reads. This only works for extent-based 413 * files, and it doesn't work if data journaling is enabled, since the 414 * dioread_nolock code uses b_private to pass information back to the 415 * I/O completion handler, and this conflicts with the jbd's use of 416 * b_private. 417 */ 418 static inline int ext4_should_dioread_nolock(struct inode *inode) 419 { 420 if (!test_opt(inode->i_sb, DIOREAD_NOLOCK)) 421 return 0; 422 if (!S_ISREG(inode->i_mode)) 423 return 0; 424 if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) 425 return 0; 426 if (ext4_should_journal_data(inode)) 427 return 0; 428 return 1; 429 } 430 431 #endif /* _EXT4_JBD2_H */ 432