xref: /linux/fs/ext4/ext4_jbd2.h (revision 5c2a430e85994f4873ea5ec42091baa1153bc731)
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 int
126 ext4_mark_iloc_dirty(handle_t *handle,
127 		     struct inode *inode,
128 		     struct ext4_iloc *iloc);
129 
130 /*
131  * On success, We end up with an outstanding reference count against
132  * iloc->bh.  This _must_ be cleaned up later.
133  */
134 
135 int ext4_reserve_inode_write(handle_t *handle, struct inode *inode,
136 			struct ext4_iloc *iloc);
137 
138 #define ext4_mark_inode_dirty(__h, __i)					\
139 		__ext4_mark_inode_dirty((__h), (__i), __func__, __LINE__)
140 int __ext4_mark_inode_dirty(handle_t *handle, struct inode *inode,
141 				const char *func, unsigned int line);
142 
143 int ext4_expand_extra_isize(struct inode *inode,
144 			    unsigned int new_extra_isize,
145 			    struct ext4_iloc *iloc);
146 /*
147  * Wrapper functions with which ext4 calls into JBD.
148  */
149 int __ext4_journal_get_write_access(const char *where, unsigned int line,
150 				    handle_t *handle, struct super_block *sb,
151 				    struct buffer_head *bh,
152 				    enum ext4_journal_trigger_type trigger_type);
153 
154 int __ext4_forget(const char *where, unsigned int line, handle_t *handle,
155 		  int is_metadata, struct inode *inode,
156 		  struct buffer_head *bh, ext4_fsblk_t blocknr);
157 
158 int __ext4_journal_get_create_access(const char *where, unsigned int line,
159 				handle_t *handle, struct super_block *sb,
160 				struct buffer_head *bh,
161 				enum ext4_journal_trigger_type trigger_type);
162 
163 int __ext4_handle_dirty_metadata(const char *where, unsigned int line,
164 				 handle_t *handle, struct inode *inode,
165 				 struct buffer_head *bh);
166 
167 #define ext4_journal_get_write_access(handle, sb, bh, trigger_type) \
168 	__ext4_journal_get_write_access(__func__, __LINE__, (handle), (sb), \
169 					(bh), (trigger_type))
170 #define ext4_forget(handle, is_metadata, inode, bh, block_nr) \
171 	__ext4_forget(__func__, __LINE__, (handle), (is_metadata), (inode), \
172 		      (bh), (block_nr))
173 #define ext4_journal_get_create_access(handle, sb, bh, trigger_type) \
174 	__ext4_journal_get_create_access(__func__, __LINE__, (handle), (sb), \
175 					 (bh), (trigger_type))
176 #define ext4_handle_dirty_metadata(handle, inode, bh) \
177 	__ext4_handle_dirty_metadata(__func__, __LINE__, (handle), (inode), \
178 				     (bh))
179 
180 handle_t *__ext4_journal_start_sb(struct inode *inode, struct super_block *sb,
181 				  unsigned int line, int type, int blocks,
182 				  int rsv_blocks, int revoke_creds);
183 int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle);
184 
185 #define EXT4_NOJOURNAL_MAX_REF_COUNT ((unsigned long) 4096)
186 
187 /* Note:  Do not use this for NULL handles.  This is only to determine if
188  * a properly allocated handle is using a journal or not. */
ext4_handle_valid(handle_t * handle)189 static inline int ext4_handle_valid(handle_t *handle)
190 {
191 	if ((unsigned long)handle < EXT4_NOJOURNAL_MAX_REF_COUNT)
192 		return 0;
193 	return 1;
194 }
195 
ext4_handle_sync(handle_t * handle)196 static inline void ext4_handle_sync(handle_t *handle)
197 {
198 	if (ext4_handle_valid(handle))
199 		handle->h_sync = 1;
200 }
201 
ext4_handle_is_aborted(handle_t * handle)202 static inline int ext4_handle_is_aborted(handle_t *handle)
203 {
204 	if (ext4_handle_valid(handle))
205 		return is_handle_aborted(handle);
206 	return 0;
207 }
208 
ext4_free_metadata_revoke_credits(struct super_block * sb,int blocks)209 static inline int ext4_free_metadata_revoke_credits(struct super_block *sb,
210 						    int blocks)
211 {
212 	/* Freeing each metadata block can result in freeing one cluster */
213 	return blocks * EXT4_SB(sb)->s_cluster_ratio;
214 }
215 
ext4_trans_default_revoke_credits(struct super_block * sb)216 static inline int ext4_trans_default_revoke_credits(struct super_block *sb)
217 {
218 	return ext4_free_metadata_revoke_credits(sb, 8);
219 }
220 
221 #define ext4_journal_start_sb(sb, type, nblocks)			\
222 	__ext4_journal_start_sb(NULL, (sb), __LINE__, (type), (nblocks), 0,\
223 				ext4_trans_default_revoke_credits(sb))
224 
225 #define ext4_journal_start(inode, type, nblocks)			\
226 	__ext4_journal_start((inode), __LINE__, (type), (nblocks), 0,	\
227 			     ext4_trans_default_revoke_credits((inode)->i_sb))
228 
229 #define ext4_journal_start_with_reserve(inode, type, blocks, rsv_blocks)\
230 	__ext4_journal_start((inode), __LINE__, (type), (blocks), (rsv_blocks),\
231 			     ext4_trans_default_revoke_credits((inode)->i_sb))
232 
233 #define ext4_journal_start_with_revoke(inode, type, blocks, revoke_creds) \
234 	__ext4_journal_start((inode), __LINE__, (type), (blocks), 0,	\
235 			     (revoke_creds))
236 
__ext4_journal_start(struct inode * inode,unsigned int line,int type,int blocks,int rsv_blocks,int revoke_creds)237 static inline handle_t *__ext4_journal_start(struct inode *inode,
238 					     unsigned int line, int type,
239 					     int blocks, int rsv_blocks,
240 					     int revoke_creds)
241 {
242 	return __ext4_journal_start_sb(inode, inode->i_sb, line, type, blocks,
243 				       rsv_blocks, revoke_creds);
244 }
245 
246 #define ext4_journal_stop(handle) \
247 	__ext4_journal_stop(__func__, __LINE__, (handle))
248 
249 #define ext4_journal_start_reserved(handle, type) \
250 	__ext4_journal_start_reserved((handle), __LINE__, (type))
251 
252 handle_t *__ext4_journal_start_reserved(handle_t *handle, unsigned int line,
253 					int type);
254 
ext4_journal_current_handle(void)255 static inline handle_t *ext4_journal_current_handle(void)
256 {
257 	return journal_current_handle();
258 }
259 
ext4_journal_extend(handle_t * handle,int nblocks,int revoke)260 static inline int ext4_journal_extend(handle_t *handle, int nblocks, int revoke)
261 {
262 	if (ext4_handle_valid(handle))
263 		return jbd2_journal_extend(handle, nblocks, revoke);
264 	return 0;
265 }
266 
ext4_journal_restart(handle_t * handle,int nblocks,int revoke)267 static inline int ext4_journal_restart(handle_t *handle, int nblocks,
268 				       int revoke)
269 {
270 	if (ext4_handle_valid(handle))
271 		return jbd2__journal_restart(handle, nblocks, revoke, GFP_NOFS);
272 	return 0;
273 }
274 
275 int __ext4_journal_ensure_credits(handle_t *handle, int check_cred,
276 				  int extend_cred, int revoke_cred);
277 
278 
279 /*
280  * Ensure @handle has at least @check_creds credits available. If not,
281  * transaction will be extended or restarted to contain at least @extend_cred
282  * credits. Before restarting transaction @fn is executed to allow for cleanup
283  * before the transaction is restarted.
284  *
285  * The return value is < 0 in case of error, 0 in case the handle has enough
286  * credits or transaction extension succeeded, 1 in case transaction had to be
287  * restarted.
288  */
289 #define ext4_journal_ensure_credits_fn(handle, check_cred, extend_cred,	\
290 				       revoke_cred, fn) \
291 ({									\
292 	__label__ __ensure_end;						\
293 	int err = __ext4_journal_ensure_credits((handle), (check_cred),	\
294 					(extend_cred), (revoke_cred));	\
295 									\
296 	if (err <= 0)							\
297 		goto __ensure_end;					\
298 	err = (fn);							\
299 	if (err < 0)							\
300 		goto __ensure_end;					\
301 	err = ext4_journal_restart((handle), (extend_cred), (revoke_cred)); \
302 	if (err == 0)							\
303 		err = 1;						\
304 __ensure_end:								\
305 	err;								\
306 })
307 
308 /*
309  * Ensure given handle has at least requested amount of credits available,
310  * possibly restarting transaction if needed. We also make sure the transaction
311  * has space for at least ext4_trans_default_revoke_credits(sb) revoke records
312  * as freeing one or two blocks is very common pattern and requesting this is
313  * very cheap.
314  */
ext4_journal_ensure_credits(handle_t * handle,int credits,int revoke_creds)315 static inline int ext4_journal_ensure_credits(handle_t *handle, int credits,
316 					      int revoke_creds)
317 {
318 	return ext4_journal_ensure_credits_fn(handle, credits, credits,
319 				revoke_creds, 0);
320 }
321 
ext4_journal_blocks_per_page(struct inode * inode)322 static inline int ext4_journal_blocks_per_page(struct inode *inode)
323 {
324 	if (EXT4_JOURNAL(inode) != NULL)
325 		return jbd2_journal_blocks_per_page(inode);
326 	return 0;
327 }
328 
ext4_journal_force_commit(journal_t * journal)329 static inline int ext4_journal_force_commit(journal_t *journal)
330 {
331 	if (journal)
332 		return jbd2_journal_force_commit(journal);
333 	return 0;
334 }
335 
ext4_jbd2_inode_add_write(handle_t * handle,struct inode * inode,loff_t start_byte,loff_t length)336 static inline int ext4_jbd2_inode_add_write(handle_t *handle,
337 		struct inode *inode, loff_t start_byte, loff_t length)
338 {
339 	if (ext4_handle_valid(handle))
340 		return jbd2_journal_inode_ranged_write(handle,
341 				EXT4_I(inode)->jinode, start_byte, length);
342 	return 0;
343 }
344 
ext4_jbd2_inode_add_wait(handle_t * handle,struct inode * inode,loff_t start_byte,loff_t length)345 static inline int ext4_jbd2_inode_add_wait(handle_t *handle,
346 		struct inode *inode, loff_t start_byte, loff_t length)
347 {
348 	if (ext4_handle_valid(handle))
349 		return jbd2_journal_inode_ranged_wait(handle,
350 				EXT4_I(inode)->jinode, start_byte, length);
351 	return 0;
352 }
353 
ext4_update_inode_fsync_trans(handle_t * handle,struct inode * inode,int datasync)354 static inline void ext4_update_inode_fsync_trans(handle_t *handle,
355 						 struct inode *inode,
356 						 int datasync)
357 {
358 	struct ext4_inode_info *ei = EXT4_I(inode);
359 
360 	if (ext4_handle_valid(handle) && !is_handle_aborted(handle)) {
361 		ei->i_sync_tid = handle->h_transaction->t_tid;
362 		if (datasync)
363 			ei->i_datasync_tid = handle->h_transaction->t_tid;
364 	}
365 }
366 
367 /* super.c */
368 int ext4_force_commit(struct super_block *sb);
369 
370 /*
371  * Ext4 inode journal modes
372  */
373 #define EXT4_INODE_JOURNAL_DATA_MODE	0x01 /* journal data mode */
374 #define EXT4_INODE_ORDERED_DATA_MODE	0x02 /* ordered data mode */
375 #define EXT4_INODE_WRITEBACK_DATA_MODE	0x04 /* writeback data mode */
376 
377 int ext4_inode_journal_mode(struct inode *inode);
378 
ext4_should_journal_data(struct inode * inode)379 static inline int ext4_should_journal_data(struct inode *inode)
380 {
381 	return ext4_inode_journal_mode(inode) & EXT4_INODE_JOURNAL_DATA_MODE;
382 }
383 
ext4_should_order_data(struct inode * inode)384 static inline int ext4_should_order_data(struct inode *inode)
385 {
386 	return ext4_inode_journal_mode(inode) & EXT4_INODE_ORDERED_DATA_MODE;
387 }
388 
ext4_should_writeback_data(struct inode * inode)389 static inline int ext4_should_writeback_data(struct inode *inode)
390 {
391 	return ext4_inode_journal_mode(inode) & EXT4_INODE_WRITEBACK_DATA_MODE;
392 }
393 
ext4_free_data_revoke_credits(struct inode * inode,int blocks)394 static inline int ext4_free_data_revoke_credits(struct inode *inode, int blocks)
395 {
396 	if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
397 		return 0;
398 	if (!ext4_should_journal_data(inode))
399 		return 0;
400 	/*
401 	 * Data blocks in one extent are contiguous, just account for partial
402 	 * clusters at extent boundaries
403 	 */
404 	return blocks + 2*(EXT4_SB(inode->i_sb)->s_cluster_ratio - 1);
405 }
406 
407 /*
408  * This function controls whether or not we should try to go down the
409  * dioread_nolock code paths, which makes it safe to avoid taking
410  * i_rwsem for direct I/O reads.  This only works for extent-based
411  * files, and it doesn't work if data journaling is enabled, since the
412  * dioread_nolock code uses b_private to pass information back to the
413  * I/O completion handler, and this conflicts with the jbd's use of
414  * b_private.
415  */
ext4_should_dioread_nolock(struct inode * inode)416 static inline int ext4_should_dioread_nolock(struct inode *inode)
417 {
418 	if (!test_opt(inode->i_sb, DIOREAD_NOLOCK))
419 		return 0;
420 	if (!S_ISREG(inode->i_mode))
421 		return 0;
422 	if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
423 		return 0;
424 	if (ext4_should_journal_data(inode))
425 		return 0;
426 	/* temporary fix to prevent generic/422 test failures */
427 	if (!test_opt(inode->i_sb, DELALLOC))
428 		return 0;
429 	return 1;
430 }
431 
432 /*
433  * Pass journal explicitly as it may not be cached in the sbi->s_journal in some
434  * cases
435  */
ext4_journal_destroy(struct ext4_sb_info * sbi,journal_t * journal)436 static inline int ext4_journal_destroy(struct ext4_sb_info *sbi, journal_t *journal)
437 {
438 	int err = 0;
439 
440 	/*
441 	 * At this point only two things can be operating on the journal.
442 	 * JBD2 thread performing transaction commit and s_sb_upd_work
443 	 * issuing sb update through the journal. Once we set
444 	 * EXT4_JOURNAL_DESTROY, new ext4_handle_error() calls will not
445 	 * queue s_sb_upd_work and ext4_force_commit() makes sure any
446 	 * ext4_handle_error() calls from the running transaction commit are
447 	 * finished. Hence no new s_sb_upd_work can be queued after we
448 	 * flush it here.
449 	 */
450 	ext4_set_mount_flag(sbi->s_sb, EXT4_MF_JOURNAL_DESTROY);
451 
452 	ext4_force_commit(sbi->s_sb);
453 	flush_work(&sbi->s_sb_upd_work);
454 
455 	err = jbd2_journal_destroy(journal);
456 	sbi->s_journal = NULL;
457 
458 	return err;
459 }
460 
461 #endif	/* _EXT4_JBD2_H */
462