ext4_jbd2.h

  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
125int
126ext4_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
135int 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__)
140int __ext4_mark_inode_dirty(handle_t *handle, struct inode *inode,
141				const char *func, unsigned int line);
142
143int 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 */
149int __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
154int __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
158int __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
163int __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
180handle_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);
183int __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. */
189static 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
196static inline void ext4_handle_sync(handle_t *handle)
197{
198	if (ext4_handle_valid(handle))
199		handle->h_sync = 1;
200}
201
202static 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
209static 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
216static 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
237static 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
252handle_t *__ext4_journal_start_reserved(handle_t *handle, unsigned int line,
253					int type);
254
255static inline handle_t *ext4_journal_current_handle(void)
256{
257	return journal_current_handle();
258}
259
260static 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
267static 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
275int __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 */
315static 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
322static inline int ext4_journal_blocks_per_folio(struct inode *inode)
323{
324	if (EXT4_JOURNAL(inode) != NULL)
325		return jbd2_journal_blocks_per_folio(inode);
326	return 0;
327}
328
329static 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
336static 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
345static 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
354static 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 */
368int 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
377int ext4_inode_journal_mode(struct inode *inode);
378
379static inline int ext4_should_journal_data(struct inode *inode)
380{
381	return ext4_inode_journal_mode(inode) & EXT4_INODE_JOURNAL_DATA_MODE;
382}
383
384static inline int ext4_should_order_data(struct inode *inode)
385{
386	return ext4_inode_journal_mode(inode) & EXT4_INODE_ORDERED_DATA_MODE;
387}
388
389static inline int ext4_should_writeback_data(struct inode *inode)
390{
391	return ext4_inode_journal_mode(inode) & EXT4_INODE_WRITEBACK_DATA_MODE;
392}
393
394static 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 */
416static 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 */
436static 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 */