1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * ext4_jbd2.h
4 *
5 * Written by Stephen C. Tweedie <sct@redhat.com>, 1999
6 *
7 * Copyright 1998--1999 Red Hat corp --- All Rights Reserved
8 *
9 * Ext4-specific journaling extensions.
10 */
11
12 #ifndef _EXT4_JBD2_H
13 #define _EXT4_JBD2_H
14
15 #include <linux/fs.h>
16 #include <linux/jbd2.h>
17 #include "ext4.h"
18
19 #define EXT4_JOURNAL(inode) (EXT4_SB((inode)->i_sb)->s_journal)
20
21 /* Define the number of blocks we need to account to a transaction to
22 * modify one block of data.
23 *
24 * We may have to touch one inode, one bitmap buffer, up to three
25 * indirection blocks, the group and superblock summaries, and the data
26 * block to complete the transaction.
27 *
28 * For extents-enabled fs we may have to allocate and modify up to
29 * 5 levels of tree, data block (for each of these we need bitmap + group
30 * summaries), root which is stored in the inode, sb
31 */
32
33 #define EXT4_SINGLEDATA_TRANS_BLOCKS(sb) \
34 (ext4_has_feature_extents(sb) ? 20U : 8U)
35
36 /* Extended attribute operations touch at most two data buffers,
37 * two bitmap buffers, and two group summaries, in addition to the inode
38 * and the superblock, which are already accounted for. */
39
40 #define EXT4_XATTR_TRANS_BLOCKS 6U
41
42 /* Define the minimum size for a transaction which modifies data. This
43 * needs to take into account the fact that we may end up modifying two
44 * quota files too (one for the group, one for the user quota). The
45 * superblock only gets updated once, of course, so don't bother
46 * counting that again for the quota updates. */
47
48 #define EXT4_DATA_TRANS_BLOCKS(sb) (EXT4_SINGLEDATA_TRANS_BLOCKS(sb) + \
49 EXT4_XATTR_TRANS_BLOCKS - 2 + \
50 EXT4_MAXQUOTAS_TRANS_BLOCKS(sb))
51
52 /*
53 * Define the number of metadata blocks we need to account to modify data.
54 *
55 * This include super block, inode block, quota blocks and xattr blocks
56 */
57 #define EXT4_META_TRANS_BLOCKS(sb) (EXT4_XATTR_TRANS_BLOCKS + \
58 EXT4_MAXQUOTAS_TRANS_BLOCKS(sb))
59
60 /* Define an arbitrary limit for the amount of data we will anticipate
61 * writing to any given transaction. For unbounded transactions such as
62 * write(2) and truncate(2) we can write more than this, but we always
63 * start off at the maximum transaction size and grow the transaction
64 * optimistically as we go. */
65
66 #define EXT4_MAX_TRANS_DATA 64U
67
68 /* We break up a large truncate or write transaction once the handle's
69 * buffer credits gets this low, we need either to extend the
70 * transaction or to start a new one. Reserve enough space here for
71 * inode, bitmap, superblock, group and indirection updates for at least
72 * one block, plus two quota updates. Quota allocations are not
73 * needed. */
74
75 #define EXT4_RESERVE_TRANS_BLOCKS 12U
76
77 /*
78 * Number of credits needed if we need to insert an entry into a
79 * directory. For each new index block, we need 4 blocks (old index
80 * block, new index block, bitmap block, bg summary). For normal
81 * htree directories there are 2 levels; if the largedir feature
82 * enabled it's 3 levels.
83 */
84 #define EXT4_INDEX_EXTRA_TRANS_BLOCKS 12U
85
86 #ifdef CONFIG_QUOTA
87 /* Amount of blocks needed for quota update - we know that the structure was
88 * allocated so we need to update only data block */
89 #define EXT4_QUOTA_TRANS_BLOCKS(sb) ((ext4_quota_capable(sb)) ? 1 : 0)
90 /* Amount of blocks needed for quota insert/delete - we do some block writes
91 * but inode, sb and group updates are done only once */
92 #define EXT4_QUOTA_INIT_BLOCKS(sb) ((ext4_quota_capable(sb)) ?\
93 (DQUOT_INIT_ALLOC*(EXT4_SINGLEDATA_TRANS_BLOCKS(sb)-3)\
94 +3+DQUOT_INIT_REWRITE) : 0)
95
96 #define EXT4_QUOTA_DEL_BLOCKS(sb) ((ext4_quota_capable(sb)) ?\
97 (DQUOT_DEL_ALLOC*(EXT4_SINGLEDATA_TRANS_BLOCKS(sb)-3)\
98 +3+DQUOT_DEL_REWRITE) : 0)
99 #else
100 #define EXT4_QUOTA_TRANS_BLOCKS(sb) 0
101 #define EXT4_QUOTA_INIT_BLOCKS(sb) 0
102 #define EXT4_QUOTA_DEL_BLOCKS(sb) 0
103 #endif
104 #define EXT4_MAXQUOTAS_TRANS_BLOCKS(sb) (EXT4_MAXQUOTAS*EXT4_QUOTA_TRANS_BLOCKS(sb))
105 #define EXT4_MAXQUOTAS_INIT_BLOCKS(sb) (EXT4_MAXQUOTAS*EXT4_QUOTA_INIT_BLOCKS(sb))
106 #define EXT4_MAXQUOTAS_DEL_BLOCKS(sb) (EXT4_MAXQUOTAS*EXT4_QUOTA_DEL_BLOCKS(sb))
107
108 /*
109 * Ext4 handle operation types -- for logging purposes
110 */
111 #define EXT4_HT_MISC 0
112 #define EXT4_HT_INODE 1
113 #define EXT4_HT_WRITE_PAGE 2
114 #define EXT4_HT_MAP_BLOCKS 3
115 #define EXT4_HT_DIR 4
116 #define EXT4_HT_TRUNCATE 5
117 #define EXT4_HT_QUOTA 6
118 #define EXT4_HT_RESIZE 7
119 #define EXT4_HT_MIGRATE 8
120 #define EXT4_HT_MOVE_EXTENTS 9
121 #define EXT4_HT_XATTR 10
122 #define EXT4_HT_EXT_CONVERT 11
123 #define EXT4_HT_MAX 12
124
125 /**
126 * struct ext4_journal_cb_entry - Base structure for callback information.
127 *
128 * This struct is a 'seed' structure for a using with your own callback
129 * structs. If you are using callbacks you must allocate one of these
130 * or another struct of your own definition which has this struct
131 * as it's first element and pass it to ext4_journal_callback_add().
132 */
133 struct ext4_journal_cb_entry {
134 /* list information for other callbacks attached to the same handle */
135 struct list_head jce_list;
136
137 /* Function to call with this callback structure */
138 void (*jce_func)(struct super_block *sb,
139 struct ext4_journal_cb_entry *jce, int error);
140
141 /* user data goes here */
142 };
143
144 /**
145 * ext4_journal_callback_add: add a function to call after transaction commit
146 * @handle: active journal transaction handle to register callback on
147 * @func: callback function to call after the transaction has committed:
148 * @sb: superblock of current filesystem for transaction
149 * @jce: returned journal callback data
150 * @rc: journal state at commit (0 = transaction committed properly)
151 * @jce: journal callback data (internal and function private data struct)
152 *
153 * The registered function will be called in the context of the journal thread
154 * after the transaction for which the handle was created has completed.
155 *
156 * No locks are held when the callback function is called, so it is safe to
157 * call blocking functions from within the callback, but the callback should
158 * not block or run for too long, or the filesystem will be blocked waiting for
159 * the next transaction to commit. No journaling functions can be used, or
160 * there is a risk of deadlock.
161 *
162 * There is no guaranteed calling order of multiple registered callbacks on
163 * the same transaction.
164 */
165 static inline void _ext4_journal_callback_add(handle_t *handle,
166 struct ext4_journal_cb_entry *jce)
167 {
168 /* Add the jce to transaction's private list */
169 list_add_tail(&jce->jce_list, &handle->h_transaction->t_private_list);
170 }
171
172 static inline void ext4_journal_callback_add(handle_t *handle,
173 void (*func)(struct super_block *sb,
174 struct ext4_journal_cb_entry *jce,
175 int rc),
176 struct ext4_journal_cb_entry *jce)
177 {
178 struct ext4_sb_info *sbi =
179 EXT4_SB(handle->h_transaction->t_journal->j_private);
180
181 /* Add the jce to transaction's private list */
182 jce->jce_func = func;
183 spin_lock(&sbi->s_md_lock);
184 _ext4_journal_callback_add(handle, jce);
185 spin_unlock(&sbi->s_md_lock);
186 }
187
188
189 /**
190 * ext4_journal_callback_del: delete a registered callback
191 * @handle: active journal transaction handle on which callback was registered
192 * @jce: registered journal callback entry to unregister
193 * Return true if object was successfully removed
194 */
195 static inline bool ext4_journal_callback_try_del(handle_t *handle,
196 struct ext4_journal_cb_entry *jce)
197 {
198 bool deleted;
199 struct ext4_sb_info *sbi =
200 EXT4_SB(handle->h_transaction->t_journal->j_private);
201
202 spin_lock(&sbi->s_md_lock);
203 deleted = !list_empty(&jce->jce_list);
204 list_del_init(&jce->jce_list);
205 spin_unlock(&sbi->s_md_lock);
206 return deleted;
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 #define ext4_mark_inode_dirty(__h, __i) \
223 __ext4_mark_inode_dirty((__h), (__i), __func__, __LINE__)
224 int __ext4_mark_inode_dirty(handle_t *handle, struct inode *inode,
225 const char *func, unsigned int line);
226
227 int ext4_expand_extra_isize(struct inode *inode,
228 unsigned int new_extra_isize,
229 struct ext4_iloc *iloc);
230 /*
231 * Wrapper functions with which ext4 calls into JBD.
232 */
233 int __ext4_journal_get_write_access(const char *where, unsigned int line,
234 handle_t *handle, struct super_block *sb,
235 struct buffer_head *bh,
236 enum ext4_journal_trigger_type trigger_type);
237
238 int __ext4_forget(const char *where, unsigned int line, handle_t *handle,
239 int is_metadata, struct inode *inode,
240 struct buffer_head *bh, ext4_fsblk_t blocknr);
241
242 int __ext4_journal_get_create_access(const char *where, unsigned int line,
243 handle_t *handle, struct super_block *sb,
244 struct buffer_head *bh,
245 enum ext4_journal_trigger_type trigger_type);
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 #define ext4_journal_get_write_access(handle, sb, bh, trigger_type) \
252 __ext4_journal_get_write_access(__func__, __LINE__, (handle), (sb), \
253 (bh), (trigger_type))
254 #define ext4_forget(handle, is_metadata, inode, bh, block_nr) \
255 __ext4_forget(__func__, __LINE__, (handle), (is_metadata), (inode), \
256 (bh), (block_nr))
257 #define ext4_journal_get_create_access(handle, sb, bh, trigger_type) \
258 __ext4_journal_get_create_access(__func__, __LINE__, (handle), (sb), \
259 (bh), (trigger_type))
260 #define ext4_handle_dirty_metadata(handle, inode, bh) \
261 __ext4_handle_dirty_metadata(__func__, __LINE__, (handle), (inode), \
262 (bh))
263
264 handle_t *__ext4_journal_start_sb(struct inode *inode, struct super_block *sb,
265 unsigned int line, int type, int blocks,
266 int rsv_blocks, int revoke_creds);
267 int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle);
268
269 #define EXT4_NOJOURNAL_MAX_REF_COUNT ((unsigned long) 4096)
270
271 /* Note: Do not use this for NULL handles. This is only to determine if
272 * a properly allocated handle is using a journal or not. */
273 static inline int ext4_handle_valid(handle_t *handle)
274 {
275 if ((unsigned long)handle < EXT4_NOJOURNAL_MAX_REF_COUNT)
276 return 0;
277 return 1;
278 }
279
280 static inline void ext4_handle_sync(handle_t *handle)
281 {
282 if (ext4_handle_valid(handle))
283 handle->h_sync = 1;
284 }
285
286 static inline int ext4_handle_is_aborted(handle_t *handle)
287 {
288 if (ext4_handle_valid(handle))
289 return is_handle_aborted(handle);
290 return 0;
291 }
292
293 static inline int ext4_free_metadata_revoke_credits(struct super_block *sb,
294 int blocks)
295 {
296 /* Freeing each metadata block can result in freeing one cluster */
297 return blocks * EXT4_SB(sb)->s_cluster_ratio;
298 }
299
300 static inline int ext4_trans_default_revoke_credits(struct super_block *sb)
301 {
302 return ext4_free_metadata_revoke_credits(sb, 8);
303 }
304
305 #define ext4_journal_start_sb(sb, type, nblocks) \
306 __ext4_journal_start_sb(NULL, (sb), __LINE__, (type), (nblocks), 0,\
307 ext4_trans_default_revoke_credits(sb))
308
309 #define ext4_journal_start(inode, type, nblocks) \
310 __ext4_journal_start((inode), __LINE__, (type), (nblocks), 0, \
311 ext4_trans_default_revoke_credits((inode)->i_sb))
312
313 #define ext4_journal_start_with_reserve(inode, type, blocks, rsv_blocks)\
314 __ext4_journal_start((inode), __LINE__, (type), (blocks), (rsv_blocks),\
315 ext4_trans_default_revoke_credits((inode)->i_sb))
316
317 #define ext4_journal_start_with_revoke(inode, type, blocks, revoke_creds) \
318 __ext4_journal_start((inode), __LINE__, (type), (blocks), 0, \
319 (revoke_creds))
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 int revoke_creds)
325 {
326 return __ext4_journal_start_sb(inode, inode->i_sb, line, type, blocks,
327 rsv_blocks, revoke_creds);
328 }
329
330 #define ext4_journal_stop(handle) \
331 __ext4_journal_stop(__func__, __LINE__, (handle))
332
333 #define ext4_journal_start_reserved(handle, type) \
334 __ext4_journal_start_reserved((handle), __LINE__, (type))
335
336 handle_t *__ext4_journal_start_reserved(handle_t *handle, unsigned int line,
337 int type);
338
339 static inline handle_t *ext4_journal_current_handle(void)
340 {
341 return journal_current_handle();
342 }
343
344 static inline int ext4_journal_extend(handle_t *handle, int nblocks, int revoke)
345 {
346 if (ext4_handle_valid(handle))
347 return jbd2_journal_extend(handle, nblocks, revoke);
348 return 0;
349 }
350
351 static inline int ext4_journal_restart(handle_t *handle, int nblocks,
352 int revoke)
353 {
354 if (ext4_handle_valid(handle))
355 return jbd2__journal_restart(handle, nblocks, revoke, GFP_NOFS);
356 return 0;
357 }
358
359 int __ext4_journal_ensure_credits(handle_t *handle, int check_cred,
360 int extend_cred, int revoke_cred);
361
362
363 /*
364 * Ensure @handle has at least @check_creds credits available. If not,
365 * transaction will be extended or restarted to contain at least @extend_cred
366 * credits. Before restarting transaction @fn is executed to allow for cleanup
367 * before the transaction is restarted.
368 *
369 * The return value is < 0 in case of error, 0 in case the handle has enough
370 * credits or transaction extension succeeded, 1 in case transaction had to be
371 * restarted.
372 */
373 #define ext4_journal_ensure_credits_fn(handle, check_cred, extend_cred, \
374 revoke_cred, fn) \
375 ({ \
376 __label__ __ensure_end; \
377 int err = __ext4_journal_ensure_credits((handle), (check_cred), \
378 (extend_cred), (revoke_cred)); \
379 \
380 if (err <= 0) \
381 goto __ensure_end; \
382 err = (fn); \
383 if (err < 0) \
384 goto __ensure_end; \
385 err = ext4_journal_restart((handle), (extend_cred), (revoke_cred)); \
386 if (err == 0) \
387 err = 1; \
388 __ensure_end: \
389 err; \
390 })
391
392 /*
393 * Ensure given handle has at least requested amount of credits available,
394 * possibly restarting transaction if needed. We also make sure the transaction
395 * has space for at least ext4_trans_default_revoke_credits(sb) revoke records
396 * as freeing one or two blocks is very common pattern and requesting this is
397 * very cheap.
398 */
399 static inline int ext4_journal_ensure_credits(handle_t *handle, int credits,
400 int revoke_creds)
401 {
402 return ext4_journal_ensure_credits_fn(handle, credits, credits,
403 revoke_creds, 0);
404 }
405
406 static inline int ext4_journal_blocks_per_page(struct inode *inode)
407 {
408 if (EXT4_JOURNAL(inode) != NULL)
409 return jbd2_journal_blocks_per_page(inode);
410 return 0;
411 }
412
413 static inline int ext4_journal_force_commit(journal_t *journal)
414 {
415 if (journal)
416 return jbd2_journal_force_commit(journal);
417 return 0;
418 }
419
420 static inline int ext4_jbd2_inode_add_write(handle_t *handle,
421 struct inode *inode, loff_t start_byte, loff_t length)
422 {
423 if (ext4_handle_valid(handle))
424 return jbd2_journal_inode_ranged_write(handle,
425 EXT4_I(inode)->jinode, start_byte, length);
426 return 0;
427 }
428
429 static inline int ext4_jbd2_inode_add_wait(handle_t *handle,
430 struct inode *inode, loff_t start_byte, loff_t length)
431 {
432 if (ext4_handle_valid(handle))
433 return jbd2_journal_inode_ranged_wait(handle,
434 EXT4_I(inode)->jinode, start_byte, length);
435 return 0;
436 }
437
438 static inline void ext4_update_inode_fsync_trans(handle_t *handle,
439 struct inode *inode,
440 int datasync)
441 {
442 struct ext4_inode_info *ei = EXT4_I(inode);
443
444 if (ext4_handle_valid(handle) && !is_handle_aborted(handle)) {
445 ei->i_sync_tid = handle->h_transaction->t_tid;
446 if (datasync)
447 ei->i_datasync_tid = handle->h_transaction->t_tid;
448 }
449 }
450
451 /* super.c */
452 int ext4_force_commit(struct super_block *sb);
453
454 /*
455 * Ext4 inode journal modes
456 */
457 #define EXT4_INODE_JOURNAL_DATA_MODE 0x01 /* journal data mode */
458 #define EXT4_INODE_ORDERED_DATA_MODE 0x02 /* ordered data mode */
459 #define EXT4_INODE_WRITEBACK_DATA_MODE 0x04 /* writeback data mode */
460
461 int ext4_inode_journal_mode(struct inode *inode);
462
463 static inline int ext4_should_journal_data(struct inode *inode)
464 {
465 return ext4_inode_journal_mode(inode) & EXT4_INODE_JOURNAL_DATA_MODE;
466 }
467
468 static inline int ext4_should_order_data(struct inode *inode)
469 {
470 return ext4_inode_journal_mode(inode) & EXT4_INODE_ORDERED_DATA_MODE;
471 }
472
473 static inline int ext4_should_writeback_data(struct inode *inode)
474 {
475 return ext4_inode_journal_mode(inode) & EXT4_INODE_WRITEBACK_DATA_MODE;
476 }
477
478 static inline int ext4_free_data_revoke_credits(struct inode *inode, int blocks)
479 {
480 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
481 return 0;
482 if (!ext4_should_journal_data(inode))
483 return 0;
484 /*
485 * Data blocks in one extent are contiguous, just account for partial
486 * clusters at extent boundaries
487 */
488 return blocks + 2*(EXT4_SB(inode->i_sb)->s_cluster_ratio - 1);
489 }
490
491 /*
492 * This function controls whether or not we should try to go down the
493 * dioread_nolock code paths, which makes it safe to avoid taking
494 * i_rwsem for direct I/O reads. This only works for extent-based
495 * files, and it doesn't work if data journaling is enabled, since the
496 * dioread_nolock code uses b_private to pass information back to the
497 * I/O completion handler, and this conflicts with the jbd's use of
498 * b_private.
499 */
500 static inline int ext4_should_dioread_nolock(struct inode *inode)
501 {
502 if (!test_opt(inode->i_sb, DIOREAD_NOLOCK))
503 return 0;
504 if (!S_ISREG(inode->i_mode))
505 return 0;
506 if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
507 return 0;
508 if (ext4_should_journal_data(inode))
509 return 0;
510 /* temporary fix to prevent generic/422 test failures */
511 if (!test_opt(inode->i_sb, DELALLOC))
512 return 0;
513 return 1;
514 }
515
516 #endif /* _EXT4_JBD2_H */
517
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