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) (MAXQUOTAS*EXT4_QUOTA_TRANS_BLOCKS(sb)) 106 #define EXT4_MAXQUOTAS_INIT_BLOCKS(sb) (MAXQUOTAS*EXT4_QUOTA_INIT_BLOCKS(sb)) 107 #define EXT4_MAXQUOTAS_DEL_BLOCKS(sb) (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_MAX 11 138 139 /** 140 * struct ext4_journal_cb_entry - Base structure for callback information. 141 * 142 * This struct is a 'seed' structure for a using with your own callback 143 * structs. If you are using callbacks you must allocate one of these 144 * or another struct of your own definition which has this struct 145 * as it's first element and pass it to ext4_journal_callback_add(). 146 */ 147 struct ext4_journal_cb_entry { 148 /* list information for other callbacks attached to the same handle */ 149 struct list_head jce_list; 150 151 /* Function to call with this callback structure */ 152 void (*jce_func)(struct super_block *sb, 153 struct ext4_journal_cb_entry *jce, int error); 154 155 /* user data goes here */ 156 }; 157 158 /** 159 * ext4_journal_callback_add: add a function to call after transaction commit 160 * @handle: active journal transaction handle to register callback on 161 * @func: callback function to call after the transaction has committed: 162 * @sb: superblock of current filesystem for transaction 163 * @jce: returned journal callback data 164 * @rc: journal state at commit (0 = transaction committed properly) 165 * @jce: journal callback data (internal and function private data struct) 166 * 167 * The registered function will be called in the context of the journal thread 168 * after the transaction for which the handle was created has completed. 169 * 170 * No locks are held when the callback function is called, so it is safe to 171 * call blocking functions from within the callback, but the callback should 172 * not block or run for too long, or the filesystem will be blocked waiting for 173 * the next transaction to commit. No journaling functions can be used, or 174 * there is a risk of deadlock. 175 * 176 * There is no guaranteed calling order of multiple registered callbacks on 177 * the same transaction. 178 */ 179 static inline void ext4_journal_callback_add(handle_t *handle, 180 void (*func)(struct super_block *sb, 181 struct ext4_journal_cb_entry *jce, 182 int rc), 183 struct ext4_journal_cb_entry *jce) 184 { 185 struct ext4_sb_info *sbi = 186 EXT4_SB(handle->h_transaction->t_journal->j_private); 187 188 /* Add the jce to transaction's private list */ 189 jce->jce_func = func; 190 spin_lock(&sbi->s_md_lock); 191 list_add_tail(&jce->jce_list, &handle->h_transaction->t_private_list); 192 spin_unlock(&sbi->s_md_lock); 193 } 194 195 /** 196 * ext4_journal_callback_del: delete a registered callback 197 * @handle: active journal transaction handle on which callback was registered 198 * @jce: registered journal callback entry to unregister 199 * Return true if object was sucessfully removed 200 */ 201 static inline bool ext4_journal_callback_try_del(handle_t *handle, 202 struct ext4_journal_cb_entry *jce) 203 { 204 bool deleted; 205 struct ext4_sb_info *sbi = 206 EXT4_SB(handle->h_transaction->t_journal->j_private); 207 208 spin_lock(&sbi->s_md_lock); 209 deleted = !list_empty(&jce->jce_list); 210 list_del_init(&jce->jce_list); 211 spin_unlock(&sbi->s_md_lock); 212 return deleted; 213 } 214 215 int 216 ext4_mark_iloc_dirty(handle_t *handle, 217 struct inode *inode, 218 struct ext4_iloc *iloc); 219 220 /* 221 * On success, We end up with an outstanding reference count against 222 * iloc->bh. This _must_ be cleaned up later. 223 */ 224 225 int ext4_reserve_inode_write(handle_t *handle, struct inode *inode, 226 struct ext4_iloc *iloc); 227 228 int ext4_mark_inode_dirty(handle_t *handle, struct inode *inode); 229 230 /* 231 * Wrapper functions with which ext4 calls into JBD. 232 */ 233 void ext4_journal_abort_handle(const char *caller, unsigned int line, 234 const char *err_fn, 235 struct buffer_head *bh, handle_t *handle, int err); 236 237 int __ext4_journal_get_write_access(const char *where, unsigned int line, 238 handle_t *handle, struct buffer_head *bh); 239 240 int __ext4_forget(const char *where, unsigned int line, handle_t *handle, 241 int is_metadata, struct inode *inode, 242 struct buffer_head *bh, ext4_fsblk_t blocknr); 243 244 int __ext4_journal_get_create_access(const char *where, unsigned int line, 245 handle_t *handle, struct buffer_head *bh); 246 247 int __ext4_handle_dirty_metadata(const char *where, unsigned int line, 248 handle_t *handle, struct inode *inode, 249 struct buffer_head *bh); 250 251 int __ext4_handle_dirty_super(const char *where, unsigned int line, 252 handle_t *handle, struct super_block *sb); 253 254 #define ext4_journal_get_write_access(handle, bh) \ 255 __ext4_journal_get_write_access(__func__, __LINE__, (handle), (bh)) 256 #define ext4_forget(handle, is_metadata, inode, bh, block_nr) \ 257 __ext4_forget(__func__, __LINE__, (handle), (is_metadata), (inode), \ 258 (bh), (block_nr)) 259 #define ext4_journal_get_create_access(handle, bh) \ 260 __ext4_journal_get_create_access(__func__, __LINE__, (handle), (bh)) 261 #define ext4_handle_dirty_metadata(handle, inode, bh) \ 262 __ext4_handle_dirty_metadata(__func__, __LINE__, (handle), (inode), \ 263 (bh)) 264 #define ext4_handle_dirty_super(handle, sb) \ 265 __ext4_handle_dirty_super(__func__, __LINE__, (handle), (sb)) 266 267 handle_t *__ext4_journal_start_sb(struct super_block *sb, unsigned int line, 268 int type, int nblocks); 269 int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle); 270 271 #define EXT4_NOJOURNAL_MAX_REF_COUNT ((unsigned long) 4096) 272 273 /* Note: Do not use this for NULL handles. This is only to determine if 274 * a properly allocated handle is using a journal or not. */ 275 static inline int ext4_handle_valid(handle_t *handle) 276 { 277 if ((unsigned long)handle < EXT4_NOJOURNAL_MAX_REF_COUNT) 278 return 0; 279 return 1; 280 } 281 282 static inline void ext4_handle_sync(handle_t *handle) 283 { 284 if (ext4_handle_valid(handle)) 285 handle->h_sync = 1; 286 } 287 288 static inline int ext4_handle_is_aborted(handle_t *handle) 289 { 290 if (ext4_handle_valid(handle)) 291 return is_handle_aborted(handle); 292 return 0; 293 } 294 295 static inline int ext4_handle_has_enough_credits(handle_t *handle, int needed) 296 { 297 if (ext4_handle_valid(handle) && handle->h_buffer_credits < needed) 298 return 0; 299 return 1; 300 } 301 302 #define ext4_journal_start_sb(sb, type, nblocks) \ 303 __ext4_journal_start_sb((sb), __LINE__, (type), (nblocks)) 304 305 #define ext4_journal_start(inode, type, nblocks) \ 306 __ext4_journal_start((inode), __LINE__, (type), (nblocks)) 307 308 static inline handle_t *__ext4_journal_start(struct inode *inode, 309 unsigned int line, int type, 310 int nblocks) 311 { 312 return __ext4_journal_start_sb(inode->i_sb, line, type, nblocks); 313 } 314 315 #define ext4_journal_stop(handle) \ 316 __ext4_journal_stop(__func__, __LINE__, (handle)) 317 318 static inline handle_t *ext4_journal_current_handle(void) 319 { 320 return journal_current_handle(); 321 } 322 323 static inline int ext4_journal_extend(handle_t *handle, int nblocks) 324 { 325 if (ext4_handle_valid(handle)) 326 return jbd2_journal_extend(handle, nblocks); 327 return 0; 328 } 329 330 static inline int ext4_journal_restart(handle_t *handle, int nblocks) 331 { 332 if (ext4_handle_valid(handle)) 333 return jbd2_journal_restart(handle, nblocks); 334 return 0; 335 } 336 337 static inline int ext4_journal_blocks_per_page(struct inode *inode) 338 { 339 if (EXT4_JOURNAL(inode) != NULL) 340 return jbd2_journal_blocks_per_page(inode); 341 return 0; 342 } 343 344 static inline int ext4_journal_force_commit(journal_t *journal) 345 { 346 if (journal) 347 return jbd2_journal_force_commit(journal); 348 return 0; 349 } 350 351 static inline int ext4_jbd2_file_inode(handle_t *handle, struct inode *inode) 352 { 353 if (ext4_handle_valid(handle)) 354 return jbd2_journal_file_inode(handle, EXT4_I(inode)->jinode); 355 return 0; 356 } 357 358 static inline void ext4_update_inode_fsync_trans(handle_t *handle, 359 struct inode *inode, 360 int datasync) 361 { 362 struct ext4_inode_info *ei = EXT4_I(inode); 363 364 if (ext4_handle_valid(handle)) { 365 ei->i_sync_tid = handle->h_transaction->t_tid; 366 if (datasync) 367 ei->i_datasync_tid = handle->h_transaction->t_tid; 368 } 369 } 370 371 /* super.c */ 372 int ext4_force_commit(struct super_block *sb); 373 374 /* 375 * Ext4 inode journal modes 376 */ 377 #define EXT4_INODE_JOURNAL_DATA_MODE 0x01 /* journal data mode */ 378 #define EXT4_INODE_ORDERED_DATA_MODE 0x02 /* ordered data mode */ 379 #define EXT4_INODE_WRITEBACK_DATA_MODE 0x04 /* writeback data mode */ 380 381 static inline int ext4_inode_journal_mode(struct inode *inode) 382 { 383 if (EXT4_JOURNAL(inode) == NULL) 384 return EXT4_INODE_WRITEBACK_DATA_MODE; /* writeback */ 385 /* We do not support data journalling with delayed allocation */ 386 if (!S_ISREG(inode->i_mode) || 387 test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) 388 return EXT4_INODE_JOURNAL_DATA_MODE; /* journal data */ 389 if (ext4_test_inode_flag(inode, EXT4_INODE_JOURNAL_DATA) && 390 !test_opt(inode->i_sb, DELALLOC)) 391 return EXT4_INODE_JOURNAL_DATA_MODE; /* journal data */ 392 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) 393 return EXT4_INODE_ORDERED_DATA_MODE; /* ordered */ 394 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA) 395 return EXT4_INODE_WRITEBACK_DATA_MODE; /* writeback */ 396 else 397 BUG(); 398 } 399 400 static inline int ext4_should_journal_data(struct inode *inode) 401 { 402 return ext4_inode_journal_mode(inode) & EXT4_INODE_JOURNAL_DATA_MODE; 403 } 404 405 static inline int ext4_should_order_data(struct inode *inode) 406 { 407 return ext4_inode_journal_mode(inode) & EXT4_INODE_ORDERED_DATA_MODE; 408 } 409 410 static inline int ext4_should_writeback_data(struct inode *inode) 411 { 412 return ext4_inode_journal_mode(inode) & EXT4_INODE_WRITEBACK_DATA_MODE; 413 } 414 415 /* 416 * This function controls whether or not we should try to go down the 417 * dioread_nolock code paths, which makes it safe to avoid taking 418 * i_mutex for direct I/O reads. This only works for extent-based 419 * files, and it doesn't work if data journaling is enabled, since the 420 * dioread_nolock code uses b_private to pass information back to the 421 * I/O completion handler, and this conflicts with the jbd's use of 422 * b_private. 423 */ 424 static inline int ext4_should_dioread_nolock(struct inode *inode) 425 { 426 if (!test_opt(inode->i_sb, DIOREAD_NOLOCK)) 427 return 0; 428 if (!S_ISREG(inode->i_mode)) 429 return 0; 430 if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) 431 return 0; 432 if (ext4_should_journal_data(inode)) 433 return 0; 434 return 1; 435 } 436 437 #endif /* _EXT4_JBD2_H */ 438