Home Home > GIT Browse
summaryrefslogtreecommitdiff
blob: f976111710231d3090bf9229d8a31a013b70b1c1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
/*
 * ext4_jbd2.h
 *
 * Written by Stephen C. Tweedie <sct@redhat.com>, 1999
 *
 * Copyright 1998--1999 Red Hat corp --- All Rights Reserved
 *
 * This file is part of the Linux kernel and is made available under
 * the terms of the GNU General Public License, version 2, or at your
 * option, any later version, incorporated herein by reference.
 *
 * Ext4-specific journaling extensions.
 */

#ifndef _EXT4_JBD2_H
#define _EXT4_JBD2_H

#include <linux/fs.h>
#include <linux/jbd2.h>
#include "ext4.h"

#define EXT4_JOURNAL(inode)	(EXT4_SB((inode)->i_sb)->s_journal)

/* Define the number of blocks we need to account to a transaction to
 * modify one block of data.
 *
 * We may have to touch one inode, one bitmap buffer, up to three
 * indirection blocks, the group and superblock summaries, and the data
 * block to complete the transaction.
 *
 * For extents-enabled fs we may have to allocate and modify up to
 * 5 levels of tree, data block (for each of these we need bitmap + group
 * summaries), root which is stored in the inode, sb
 */

#define EXT4_SINGLEDATA_TRANS_BLOCKS(sb)				\
	(ext4_has_feature_extents(sb) ? 20U : 8U)

/* Extended attribute operations touch at most two data buffers,
 * two bitmap buffers, and two group summaries, in addition to the inode
 * and the superblock, which are already accounted for. */

#define EXT4_XATTR_TRANS_BLOCKS		6U

/* Define the minimum size for a transaction which modifies data.  This
 * needs to take into account the fact that we may end up modifying two
 * quota files too (one for the group, one for the user quota).  The
 * superblock only gets updated once, of course, so don't bother
 * counting that again for the quota updates. */

#define EXT4_DATA_TRANS_BLOCKS(sb)	(EXT4_SINGLEDATA_TRANS_BLOCKS(sb) + \
					 EXT4_XATTR_TRANS_BLOCKS - 2 + \
					 EXT4_MAXQUOTAS_TRANS_BLOCKS(sb))

/*
 * Define the number of metadata blocks we need to account to modify data.
 *
 * This include super block, inode block, quota blocks and xattr blocks
 */
#define EXT4_META_TRANS_BLOCKS(sb)	(EXT4_XATTR_TRANS_BLOCKS + \
					EXT4_MAXQUOTAS_TRANS_BLOCKS(sb))

/* Define an arbitrary limit for the amount of data we will anticipate
 * writing to any given transaction.  For unbounded transactions such as
 * write(2) and truncate(2) we can write more than this, but we always
 * start off at the maximum transaction size and grow the transaction
 * optimistically as we go. */

#define EXT4_MAX_TRANS_DATA		64U

/* We break up a large truncate or write transaction once the handle's
 * buffer credits gets this low, we need either to extend the
 * transaction or to start a new one.  Reserve enough space here for
 * inode, bitmap, superblock, group and indirection updates for at least
 * one block, plus two quota updates.  Quota allocations are not
 * needed. */

#define EXT4_RESERVE_TRANS_BLOCKS	12U

#define EXT4_INDEX_EXTRA_TRANS_BLOCKS	8

#ifdef CONFIG_QUOTA
/* Amount of blocks needed for quota update - we know that the structure was
 * allocated so we need to update only data block */
#define EXT4_QUOTA_TRANS_BLOCKS(sb) ((test_opt(sb, QUOTA) ||\
		ext4_has_feature_quota(sb)) ? 1 : 0)
/* Amount of blocks needed for quota insert/delete - we do some block writes
 * but inode, sb and group updates are done only once */
#define EXT4_QUOTA_INIT_BLOCKS(sb) ((test_opt(sb, QUOTA) ||\
		ext4_has_feature_quota(sb)) ?\
		(DQUOT_INIT_ALLOC*(EXT4_SINGLEDATA_TRANS_BLOCKS(sb)-3)\
		 +3+DQUOT_INIT_REWRITE) : 0)

#define EXT4_QUOTA_DEL_BLOCKS(sb) ((test_opt(sb, QUOTA) ||\
		ext4_has_feature_quota(sb)) ?\
		(DQUOT_DEL_ALLOC*(EXT4_SINGLEDATA_TRANS_BLOCKS(sb)-3)\
		 +3+DQUOT_DEL_REWRITE) : 0)
#else
#define EXT4_QUOTA_TRANS_BLOCKS(sb) 0
#define EXT4_QUOTA_INIT_BLOCKS(sb) 0
#define EXT4_QUOTA_DEL_BLOCKS(sb) 0
#endif
#define EXT4_MAXQUOTAS_TRANS_BLOCKS(sb) (EXT4_MAXQUOTAS*EXT4_QUOTA_TRANS_BLOCKS(sb))
#define EXT4_MAXQUOTAS_INIT_BLOCKS(sb) (EXT4_MAXQUOTAS*EXT4_QUOTA_INIT_BLOCKS(sb))
#define EXT4_MAXQUOTAS_DEL_BLOCKS(sb) (EXT4_MAXQUOTAS*EXT4_QUOTA_DEL_BLOCKS(sb))

static inline int ext4_jbd2_credits_xattr(struct inode *inode)
{
	int credits = EXT4_DATA_TRANS_BLOCKS(inode->i_sb);

	/*
	 * In case of inline data, we may push out the data to a block,
	 * so we need to reserve credits for this eventuality
	 */
	if (ext4_has_inline_data(inode))
		credits += ext4_writepage_trans_blocks(inode) + 1;
	return credits;
}


/*
 * Ext4 handle operation types -- for logging purposes
 */
#define EXT4_HT_MISC             0
#define EXT4_HT_INODE            1
#define EXT4_HT_WRITE_PAGE       2
#define EXT4_HT_MAP_BLOCKS       3
#define EXT4_HT_DIR              4
#define EXT4_HT_TRUNCATE         5
#define EXT4_HT_QUOTA            6
#define EXT4_HT_RESIZE           7
#define EXT4_HT_MIGRATE          8
#define EXT4_HT_MOVE_EXTENTS     9
#define EXT4_HT_XATTR           10
#define EXT4_HT_EXT_CONVERT     11
#define EXT4_HT_MAX             12

/**
 *   struct ext4_journal_cb_entry - Base structure for callback information.
 *
 *   This struct is a 'seed' structure for a using with your own callback
 *   structs. If you are using callbacks you must allocate one of these
 *   or another struct of your own definition which has this struct
 *   as it's first element and pass it to ext4_journal_callback_add().
 */
struct ext4_journal_cb_entry {
	/* list information for other callbacks attached to the same handle */
	struct list_head jce_list;

	/*  Function to call with this callback structure */
	void (*jce_func)(struct super_block *sb,
			 struct ext4_journal_cb_entry *jce, int error);

	/* user data goes here */
};

/**
 * ext4_journal_callback_add: add a function to call after transaction commit
 * @handle: active journal transaction handle to register callback on
 * @func: callback function to call after the transaction has committed:
 *        @sb: superblock of current filesystem for transaction
 *        @jce: returned journal callback data
 *        @rc: journal state at commit (0 = transaction committed properly)
 * @jce: journal callback data (internal and function private data struct)
 *
 * The registered function will be called in the context of the journal thread
 * after the transaction for which the handle was created has completed.
 *
 * No locks are held when the callback function is called, so it is safe to
 * call blocking functions from within the callback, but the callback should
 * not block or run for too long, or the filesystem will be blocked waiting for
 * the next transaction to commit. No journaling functions can be used, or
 * there is a risk of deadlock.
 *
 * There is no guaranteed calling order of multiple registered callbacks on
 * the same transaction.
 */
static inline void _ext4_journal_callback_add(handle_t *handle,
			struct ext4_journal_cb_entry *jce)
{
	/* Add the jce to transaction's private list */
	list_add_tail(&jce->jce_list, &handle->h_transaction->t_private_list);
}

static inline void ext4_journal_callback_add(handle_t *handle,
			void (*func)(struct super_block *sb,
				     struct ext4_journal_cb_entry *jce,
				     int rc),
			struct ext4_journal_cb_entry *jce)
{
	struct ext4_sb_info *sbi =
			EXT4_SB(handle->h_transaction->t_journal->j_private);

	/* Add the jce to transaction's private list */
	jce->jce_func = func;
	spin_lock(&sbi->s_md_lock);
	_ext4_journal_callback_add(handle, jce);
	spin_unlock(&sbi->s_md_lock);
}


/**
 * ext4_journal_callback_del: delete a registered callback
 * @handle: active journal transaction handle on which callback was registered
 * @jce: registered journal callback entry to unregister
 * Return true if object was successfully removed
 */
static inline bool ext4_journal_callback_try_del(handle_t *handle,
					     struct ext4_journal_cb_entry *jce)
{
	bool deleted;
	struct ext4_sb_info *sbi =
			EXT4_SB(handle->h_transaction->t_journal->j_private);

	spin_lock(&sbi->s_md_lock);
	deleted = !list_empty(&jce->jce_list);
	list_del_init(&jce->jce_list);
	spin_unlock(&sbi->s_md_lock);
	return deleted;
}

int
ext4_mark_iloc_dirty(handle_t *handle,
		     struct inode *inode,
		     struct ext4_iloc *iloc);

/*
 * On success, We end up with an outstanding reference count against
 * iloc->bh.  This _must_ be cleaned up later.
 */

int ext4_reserve_inode_write(handle_t *handle, struct inode *inode,
			struct ext4_iloc *iloc);

int ext4_mark_inode_dirty(handle_t *handle, struct inode *inode);

/*
 * Wrapper functions with which ext4 calls into JBD.
 */
int __ext4_journal_get_write_access(const char *where, unsigned int line,
				    handle_t *handle, struct buffer_head *bh);

int __ext4_forget(const char *where, unsigned int line, handle_t *handle,
		  int is_metadata, struct inode *inode,
		  struct buffer_head *bh, ext4_fsblk_t blocknr);

int __ext4_journal_get_create_access(const char *where, unsigned int line,
				handle_t *handle, struct buffer_head *bh);

int __ext4_handle_dirty_metadata(const char *where, unsigned int line,
				 handle_t *handle, struct inode *inode,
				 struct buffer_head *bh);

int __ext4_handle_dirty_super(const char *where, unsigned int line,
			      handle_t *handle, struct super_block *sb);

#define ext4_journal_get_write_access(handle, bh) \
	__ext4_journal_get_write_access(__func__, __LINE__, (handle), (bh))
#define ext4_forget(handle, is_metadata, inode, bh, block_nr) \
	__ext4_forget(__func__, __LINE__, (handle), (is_metadata), (inode), \
		      (bh), (block_nr))
#define ext4_journal_get_create_access(handle, bh) \
	__ext4_journal_get_create_access(__func__, __LINE__, (handle), (bh))
#define ext4_handle_dirty_metadata(handle, inode, bh) \
	__ext4_handle_dirty_metadata(__func__, __LINE__, (handle), (inode), \
				     (bh))
#define ext4_handle_dirty_super(handle, sb) \
	__ext4_handle_dirty_super(__func__, __LINE__, (handle), (sb))

handle_t *__ext4_journal_start_sb(struct super_block *sb, unsigned int line,
				  int type, int blocks, int rsv_blocks);
int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle);

#define EXT4_NOJOURNAL_MAX_REF_COUNT ((unsigned long) 4096)

/* Note:  Do not use this for NULL handles.  This is only to determine if
 * a properly allocated handle is using a journal or not. */
static inline int ext4_handle_valid(handle_t *handle)
{
	if ((unsigned long)handle < EXT4_NOJOURNAL_MAX_REF_COUNT)
		return 0;
	return 1;
}

static inline void ext4_handle_sync(handle_t *handle)
{
	if (ext4_handle_valid(handle))
		handle->h_sync = 1;
}

static inline int ext4_handle_is_aborted(handle_t *handle)
{
	if (ext4_handle_valid(handle))
		return is_handle_aborted(handle);
	return 0;
}

static inline int ext4_handle_has_enough_credits(handle_t *handle, int needed)
{
	if (ext4_handle_valid(handle) && handle->h_buffer_credits < needed)
		return 0;
	return 1;
}

#define ext4_journal_start_sb(sb, type, nblocks)			\
	__ext4_journal_start_sb((sb), __LINE__, (type), (nblocks), 0)

#define ext4_journal_start(inode, type, nblocks)			\
	__ext4_journal_start((inode), __LINE__, (type), (nblocks), 0)

#define ext4_journal_start_with_reserve(inode, type, blocks, rsv_blocks) \
	__ext4_journal_start((inode), __LINE__, (type), (blocks), (rsv_blocks))

static inline handle_t *__ext4_journal_start(struct inode *inode,
					     unsigned int line, int type,
					     int blocks, int rsv_blocks)
{
	return __ext4_journal_start_sb(inode->i_sb, line, type, blocks,
				       rsv_blocks);
}

#define ext4_journal_stop(handle) \
	__ext4_journal_stop(__func__, __LINE__, (handle))

#define ext4_journal_start_reserved(handle, type) \
	__ext4_journal_start_reserved((handle), __LINE__, (type))

handle_t *__ext4_journal_start_reserved(handle_t *handle, unsigned int line,
					int type);

static inline void ext4_journal_free_reserved(handle_t *handle)
{
	if (ext4_handle_valid(handle))
		jbd2_journal_free_reserved(handle);
}

static inline handle_t *ext4_journal_current_handle(void)
{
	return journal_current_handle();
}

static inline int ext4_journal_extend(handle_t *handle, int nblocks)
{
	if (ext4_handle_valid(handle))
		return jbd2_journal_extend(handle, nblocks);
	return 0;
}

static inline int ext4_journal_restart(handle_t *handle, int nblocks)
{
	if (ext4_handle_valid(handle))
		return jbd2_journal_restart(handle, nblocks);
	return 0;
}

static inline int ext4_journal_blocks_per_page(struct inode *inode)
{
	if (EXT4_JOURNAL(inode) != NULL)
		return jbd2_journal_blocks_per_page(inode);
	return 0;
}

static inline int ext4_journal_force_commit(journal_t *journal)
{
	if (journal)
		return jbd2_journal_force_commit(journal);
	return 0;
}

static inline int ext4_jbd2_inode_add_write(handle_t *handle,
					    struct inode *inode)
{
	if (ext4_handle_valid(handle))
		return jbd2_journal_inode_add_write(handle,
						    EXT4_I(inode)->jinode);
	return 0;
}

static inline int ext4_jbd2_inode_add_wait(handle_t *handle,
					   struct inode *inode)
{
	if (ext4_handle_valid(handle))
		return jbd2_journal_inode_add_wait(handle,
						   EXT4_I(inode)->jinode);
	return 0;
}

static inline void ext4_update_inode_fsync_trans(handle_t *handle,
						 struct inode *inode,
						 int datasync)
{
	struct ext4_inode_info *ei = EXT4_I(inode);

	if (ext4_handle_valid(handle)) {
		ei->i_sync_tid = handle->h_transaction->t_tid;
		if (datasync)
			ei->i_datasync_tid = handle->h_transaction->t_tid;
	}
}

/* super.c */
int ext4_force_commit(struct super_block *sb);

/*
 * Ext4 inode journal modes
 */
#define EXT4_INODE_JOURNAL_DATA_MODE	0x01 /* journal data mode */
#define EXT4_INODE_ORDERED_DATA_MODE	0x02 /* ordered data mode */
#define EXT4_INODE_WRITEBACK_DATA_MODE	0x04 /* writeback data mode */

static inline int ext4_inode_journal_mode(struct inode *inode)
{
	if (EXT4_JOURNAL(inode) == NULL)
		return EXT4_INODE_WRITEBACK_DATA_MODE;	/* writeback */
	/* We do not support data journalling with delayed allocation */
	if (!S_ISREG(inode->i_mode) ||
	    test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA ||
	    (ext4_test_inode_flag(inode, EXT4_INODE_JOURNAL_DATA) &&
	    !test_opt(inode->i_sb, DELALLOC))) {
		/* We do not support data journalling for encrypted data */
		if (S_ISREG(inode->i_mode) && ext4_encrypted_inode(inode))
			return EXT4_INODE_ORDERED_DATA_MODE;  /* ordered */
		return EXT4_INODE_JOURNAL_DATA_MODE;	/* journal data */
	}
	if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
		return EXT4_INODE_ORDERED_DATA_MODE;	/* ordered */
	if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
		return EXT4_INODE_WRITEBACK_DATA_MODE;	/* writeback */
	BUG();
}

static inline int ext4_should_journal_data(struct inode *inode)
{
	return ext4_inode_journal_mode(inode) & EXT4_INODE_JOURNAL_DATA_MODE;
}

static inline int ext4_should_order_data(struct inode *inode)
{
	return ext4_inode_journal_mode(inode) & EXT4_INODE_ORDERED_DATA_MODE;
}

static inline int ext4_should_writeback_data(struct inode *inode)
{
	return ext4_inode_journal_mode(inode) & EXT4_INODE_WRITEBACK_DATA_MODE;
}

/*
 * This function controls whether or not we should try to go down the
 * dioread_nolock code paths, which makes it safe to avoid taking
 * i_mutex for direct I/O reads.  This only works for extent-based
 * files, and it doesn't work if data journaling is enabled, since the
 * dioread_nolock code uses b_private to pass information back to the
 * I/O completion handler, and this conflicts with the jbd's use of
 * b_private.
 */
static inline int ext4_should_dioread_nolock(struct inode *inode)
{
	if (!test_opt(inode->i_sb, DIOREAD_NOLOCK))
		return 0;
	if (!S_ISREG(inode->i_mode))
		return 0;
	if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
		return 0;
	if (ext4_should_journal_data(inode))
		return 0;
	return 1;
}

#endif	/* _EXT4_JBD2_H */