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v3.5.6
 
  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 + root which are stored in the inode. */
 
 
 33
 34#define EXT4_SINGLEDATA_TRANS_BLOCKS(sb)				\
 35	(EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)   \
 36	 ? 27U : 8U)
 37
 38/* Extended attribute operations touch at most two data buffers,
 39 * two bitmap buffers, and two group summaries, in addition to the inode
 40 * and the superblock, which are already accounted for. */
 41
 42#define EXT4_XATTR_TRANS_BLOCKS		6U
 43
 44/* Define the minimum size for a transaction which modifies data.  This
 45 * needs to take into account the fact that we may end up modifying two
 46 * quota files too (one for the group, one for the user quota).  The
 47 * superblock only gets updated once, of course, so don't bother
 48 * counting that again for the quota updates. */
 49
 50#define EXT4_DATA_TRANS_BLOCKS(sb)	(EXT4_SINGLEDATA_TRANS_BLOCKS(sb) + \
 51					 EXT4_XATTR_TRANS_BLOCKS - 2 + \
 52					 EXT4_MAXQUOTAS_TRANS_BLOCKS(sb))
 53
 54/*
 55 * Define the number of metadata blocks we need to account to modify data.
 56 *
 57 * This include super block, inode block, quota blocks and xattr blocks
 58 */
 59#define EXT4_META_TRANS_BLOCKS(sb)	(EXT4_XATTR_TRANS_BLOCKS + \
 60					EXT4_MAXQUOTAS_TRANS_BLOCKS(sb))
 61
 62/* Delete operations potentially hit one directory's namespace plus an
 63 * entire inode, plus arbitrary amounts of bitmap/indirection data.  Be
 64 * generous.  We can grow the delete transaction later if necessary. */
 65
 66#define EXT4_DELETE_TRANS_BLOCKS(sb)	(2 * EXT4_DATA_TRANS_BLOCKS(sb) + 64)
 67
 68/* Define an arbitrary limit for the amount of data we will anticipate
 69 * writing to any given transaction.  For unbounded transactions such as
 70 * write(2) and truncate(2) we can write more than this, but we always
 71 * start off at the maximum transaction size and grow the transaction
 72 * optimistically as we go. */
 73
 74#define EXT4_MAX_TRANS_DATA		64U
 75
 76/* We break up a large truncate or write transaction once the handle's
 77 * buffer credits gets this low, we need either to extend the
 78 * transaction or to start a new one.  Reserve enough space here for
 79 * inode, bitmap, superblock, group and indirection updates for at least
 80 * one block, plus two quota updates.  Quota allocations are not
 81 * needed. */
 82
 83#define EXT4_RESERVE_TRANS_BLOCKS	12U
 84
 85#define EXT4_INDEX_EXTRA_TRANS_BLOCKS	8
 
 
 
 
 
 
 
 86
 87#ifdef CONFIG_QUOTA
 88/* Amount of blocks needed for quota update - we know that the structure was
 89 * allocated so we need to update only data block */
 90#define EXT4_QUOTA_TRANS_BLOCKS(sb) (test_opt(sb, QUOTA) ? 1 : 0)
 
 91/* Amount of blocks needed for quota insert/delete - we do some block writes
 92 * but inode, sb and group updates are done only once */
 93#define EXT4_QUOTA_INIT_BLOCKS(sb) (test_opt(sb, QUOTA) ? (DQUOT_INIT_ALLOC*\
 94		(EXT4_SINGLEDATA_TRANS_BLOCKS(sb)-3)+3+DQUOT_INIT_REWRITE) : 0)
 95
 96#define EXT4_QUOTA_DEL_BLOCKS(sb) (test_opt(sb, QUOTA) ? (DQUOT_DEL_ALLOC*\
 97		(EXT4_SINGLEDATA_TRANS_BLOCKS(sb)-3)+3+DQUOT_DEL_REWRITE) : 0)
 
 
 
 
 98#else
 99#define EXT4_QUOTA_TRANS_BLOCKS(sb) 0
100#define EXT4_QUOTA_INIT_BLOCKS(sb) 0
101#define EXT4_QUOTA_DEL_BLOCKS(sb) 0
102#endif
103#define EXT4_MAXQUOTAS_TRANS_BLOCKS(sb) (MAXQUOTAS*EXT4_QUOTA_TRANS_BLOCKS(sb))
104#define EXT4_MAXQUOTAS_INIT_BLOCKS(sb) (MAXQUOTAS*EXT4_QUOTA_INIT_BLOCKS(sb))
105#define EXT4_MAXQUOTAS_DEL_BLOCKS(sb) (MAXQUOTAS*EXT4_QUOTA_DEL_BLOCKS(sb))
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
106
107/**
108 *   struct ext4_journal_cb_entry - Base structure for callback information.
109 *
110 *   This struct is a 'seed' structure for a using with your own callback
111 *   structs. If you are using callbacks you must allocate one of these
112 *   or another struct of your own definition which has this struct
113 *   as it's first element and pass it to ext4_journal_callback_add().
114 */
115struct ext4_journal_cb_entry {
116	/* list information for other callbacks attached to the same handle */
117	struct list_head jce_list;
118
119	/*  Function to call with this callback structure */
120	void (*jce_func)(struct super_block *sb,
121			 struct ext4_journal_cb_entry *jce, int error);
122
123	/* user data goes here */
124};
125
126/**
127 * ext4_journal_callback_add: add a function to call after transaction commit
128 * @handle: active journal transaction handle to register callback on
129 * @func: callback function to call after the transaction has committed:
130 *        @sb: superblock of current filesystem for transaction
131 *        @jce: returned journal callback data
132 *        @rc: journal state at commit (0 = transaction committed properly)
133 * @jce: journal callback data (internal and function private data struct)
134 *
135 * The registered function will be called in the context of the journal thread
136 * after the transaction for which the handle was created has completed.
137 *
138 * No locks are held when the callback function is called, so it is safe to
139 * call blocking functions from within the callback, but the callback should
140 * not block or run for too long, or the filesystem will be blocked waiting for
141 * the next transaction to commit. No journaling functions can be used, or
142 * there is a risk of deadlock.
143 *
144 * There is no guaranteed calling order of multiple registered callbacks on
145 * the same transaction.
146 */
 
 
 
 
 
 
 
147static inline void ext4_journal_callback_add(handle_t *handle,
148			void (*func)(struct super_block *sb,
149				     struct ext4_journal_cb_entry *jce,
150				     int rc),
151			struct ext4_journal_cb_entry *jce)
152{
153	struct ext4_sb_info *sbi =
154			EXT4_SB(handle->h_transaction->t_journal->j_private);
155
156	/* Add the jce to transaction's private list */
157	jce->jce_func = func;
158	spin_lock(&sbi->s_md_lock);
159	list_add_tail(&jce->jce_list, &handle->h_transaction->t_private_list);
160	spin_unlock(&sbi->s_md_lock);
161}
162
 
163/**
164 * ext4_journal_callback_del: delete a registered callback
165 * @handle: active journal transaction handle on which callback was registered
166 * @jce: registered journal callback entry to unregister
 
167 */
168static inline void ext4_journal_callback_del(handle_t *handle,
169					     struct ext4_journal_cb_entry *jce)
170{
 
171	struct ext4_sb_info *sbi =
172			EXT4_SB(handle->h_transaction->t_journal->j_private);
173
174	spin_lock(&sbi->s_md_lock);
 
175	list_del_init(&jce->jce_list);
176	spin_unlock(&sbi->s_md_lock);
 
177}
178
179int
180ext4_mark_iloc_dirty(handle_t *handle,
181		     struct inode *inode,
182		     struct ext4_iloc *iloc);
183
184/*
185 * On success, We end up with an outstanding reference count against
186 * iloc->bh.  This _must_ be cleaned up later.
187 */
188
189int ext4_reserve_inode_write(handle_t *handle, struct inode *inode,
190			struct ext4_iloc *iloc);
191
192int ext4_mark_inode_dirty(handle_t *handle, struct inode *inode);
193
 
 
 
 
 
 
194/*
195 * Wrapper functions with which ext4 calls into JBD.
196 */
197void ext4_journal_abort_handle(const char *caller, unsigned int line,
198			       const char *err_fn,
199		struct buffer_head *bh, handle_t *handle, int err);
200
201int __ext4_journal_get_write_access(const char *where, unsigned int line,
202				    handle_t *handle, struct buffer_head *bh);
203
204int __ext4_forget(const char *where, unsigned int line, handle_t *handle,
205		  int is_metadata, struct inode *inode,
206		  struct buffer_head *bh, ext4_fsblk_t blocknr);
207
208int __ext4_journal_get_create_access(const char *where, unsigned int line,
209				handle_t *handle, struct buffer_head *bh);
210
211int __ext4_handle_dirty_metadata(const char *where, unsigned int line,
212				 handle_t *handle, struct inode *inode,
213				 struct buffer_head *bh);
214
215int __ext4_handle_dirty_super(const char *where, unsigned int line,
216			      handle_t *handle, struct super_block *sb,
217			      int now);
218
219#define ext4_journal_get_write_access(handle, bh) \
220	__ext4_journal_get_write_access(__func__, __LINE__, (handle), (bh))
221#define ext4_forget(handle, is_metadata, inode, bh, block_nr) \
222	__ext4_forget(__func__, __LINE__, (handle), (is_metadata), (inode), \
223		      (bh), (block_nr))
224#define ext4_journal_get_create_access(handle, bh) \
225	__ext4_journal_get_create_access(__func__, __LINE__, (handle), (bh))
226#define ext4_handle_dirty_metadata(handle, inode, bh) \
227	__ext4_handle_dirty_metadata(__func__, __LINE__, (handle), (inode), \
228				     (bh))
229#define ext4_handle_dirty_super_now(handle, sb) \
230	__ext4_handle_dirty_super(__func__, __LINE__, (handle), (sb), 1)
231#define ext4_handle_dirty_super(handle, sb) \
232	__ext4_handle_dirty_super(__func__, __LINE__, (handle), (sb), 0)
233
234handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks);
 
 
235int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle);
236
237#define EXT4_NOJOURNAL_MAX_REF_COUNT ((unsigned long) 4096)
238
239/* Note:  Do not use this for NULL handles.  This is only to determine if
240 * a properly allocated handle is using a journal or not. */
241static inline int ext4_handle_valid(handle_t *handle)
242{
243	if ((unsigned long)handle < EXT4_NOJOURNAL_MAX_REF_COUNT)
244		return 0;
245	return 1;
246}
247
248static inline void ext4_handle_sync(handle_t *handle)
249{
250	if (ext4_handle_valid(handle))
251		handle->h_sync = 1;
252}
253
254static inline void ext4_handle_release_buffer(handle_t *handle,
255						struct buffer_head *bh)
256{
257	if (ext4_handle_valid(handle))
258		jbd2_journal_release_buffer(handle, bh);
259}
260
261static inline int ext4_handle_is_aborted(handle_t *handle)
262{
263	if (ext4_handle_valid(handle))
264		return is_handle_aborted(handle);
265	return 0;
266}
267
268static inline int ext4_handle_has_enough_credits(handle_t *handle, int needed)
 
269{
270	if (ext4_handle_valid(handle) && handle->h_buffer_credits < needed)
271		return 0;
272	return 1;
 
 
 
 
273}
274
275static inline handle_t *ext4_journal_start(struct inode *inode, int nblocks)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
276{
277	return ext4_journal_start_sb(inode->i_sb, nblocks);
 
278}
279
280#define ext4_journal_stop(handle) \
281	__ext4_journal_stop(__func__, __LINE__, (handle))
282
 
 
 
 
 
 
283static inline handle_t *ext4_journal_current_handle(void)
284{
285	return journal_current_handle();
286}
287
288static inline int ext4_journal_extend(handle_t *handle, int nblocks)
289{
290	if (ext4_handle_valid(handle))
291		return jbd2_journal_extend(handle, nblocks);
292	return 0;
293}
294
295static inline int ext4_journal_restart(handle_t *handle, int nblocks)
 
296{
297	if (ext4_handle_valid(handle))
298		return jbd2_journal_restart(handle, nblocks);
299	return 0;
300}
301
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
302static inline int ext4_journal_blocks_per_page(struct inode *inode)
303{
304	if (EXT4_JOURNAL(inode) != NULL)
305		return jbd2_journal_blocks_per_page(inode);
306	return 0;
307}
308
309static inline int ext4_journal_force_commit(journal_t *journal)
310{
311	if (journal)
312		return jbd2_journal_force_commit(journal);
313	return 0;
314}
315
316static inline int ext4_jbd2_file_inode(handle_t *handle, struct inode *inode)
 
317{
318	if (ext4_handle_valid(handle))
319		return jbd2_journal_file_inode(handle, EXT4_I(inode)->jinode);
 
 
 
 
 
 
 
 
 
 
320	return 0;
321}
322
323static inline void ext4_update_inode_fsync_trans(handle_t *handle,
324						 struct inode *inode,
325						 int datasync)
326{
327	struct ext4_inode_info *ei = EXT4_I(inode);
328
329	if (ext4_handle_valid(handle)) {
330		ei->i_sync_tid = handle->h_transaction->t_tid;
331		if (datasync)
332			ei->i_datasync_tid = handle->h_transaction->t_tid;
333	}
334}
335
336/* super.c */
337int ext4_force_commit(struct super_block *sb);
338
339/*
340 * Ext4 inode journal modes
341 */
342#define EXT4_INODE_JOURNAL_DATA_MODE	0x01 /* journal data mode */
343#define EXT4_INODE_ORDERED_DATA_MODE	0x02 /* ordered data mode */
344#define EXT4_INODE_WRITEBACK_DATA_MODE	0x04 /* writeback data mode */
345
346static inline int ext4_inode_journal_mode(struct inode *inode)
347{
348	if (EXT4_JOURNAL(inode) == NULL)
349		return EXT4_INODE_WRITEBACK_DATA_MODE;	/* writeback */
350	/* We do not support data journalling with delayed allocation */
351	if (!S_ISREG(inode->i_mode) ||
352	    test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
353		return EXT4_INODE_JOURNAL_DATA_MODE;	/* journal data */
354	if (ext4_test_inode_flag(inode, EXT4_INODE_JOURNAL_DATA) &&
355	    !test_opt(inode->i_sb, DELALLOC))
356		return EXT4_INODE_JOURNAL_DATA_MODE;	/* journal data */
357	if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
358		return EXT4_INODE_ORDERED_DATA_MODE;	/* ordered */
359	if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
360		return EXT4_INODE_WRITEBACK_DATA_MODE;	/* writeback */
361	else
362		BUG();
363}
364
365static inline int ext4_should_journal_data(struct inode *inode)
366{
367	return ext4_inode_journal_mode(inode) & EXT4_INODE_JOURNAL_DATA_MODE;
368}
369
370static inline int ext4_should_order_data(struct inode *inode)
371{
372	return ext4_inode_journal_mode(inode) & EXT4_INODE_ORDERED_DATA_MODE;
373}
374
375static inline int ext4_should_writeback_data(struct inode *inode)
376{
377	return ext4_inode_journal_mode(inode) & EXT4_INODE_WRITEBACK_DATA_MODE;
378}
379
 
 
 
 
 
 
 
 
 
 
 
 
 
380/*
381 * This function controls whether or not we should try to go down the
382 * dioread_nolock code paths, which makes it safe to avoid taking
383 * i_mutex for direct I/O reads.  This only works for extent-based
384 * files, and it doesn't work if data journaling is enabled, since the
385 * dioread_nolock code uses b_private to pass information back to the
386 * I/O completion handler, and this conflicts with the jbd's use of
387 * b_private.
388 */
389static inline int ext4_should_dioread_nolock(struct inode *inode)
390{
391	if (!test_opt(inode->i_sb, DIOREAD_NOLOCK))
392		return 0;
393	if (!S_ISREG(inode->i_mode))
394		return 0;
395	if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
396		return 0;
397	if (ext4_should_journal_data(inode))
 
 
 
398		return 0;
399	return 1;
400}
401
402#endif	/* _EXT4_JBD2_H */
v5.9
  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) ((test_opt(sb, QUOTA) ||\
 90		ext4_has_feature_quota(sb)) ? 1 : 0)
 91/* Amount of blocks needed for quota insert/delete - we do some block writes
 92 * but inode, sb and group updates are done only once */
 93#define EXT4_QUOTA_INIT_BLOCKS(sb) ((test_opt(sb, QUOTA) ||\
 94		ext4_has_feature_quota(sb)) ?\
 95		(DQUOT_INIT_ALLOC*(EXT4_SINGLEDATA_TRANS_BLOCKS(sb)-3)\
 96		 +3+DQUOT_INIT_REWRITE) : 0)
 97
 98#define EXT4_QUOTA_DEL_BLOCKS(sb) ((test_opt(sb, QUOTA) ||\
 99		ext4_has_feature_quota(sb)) ?\
100		(DQUOT_DEL_ALLOC*(EXT4_SINGLEDATA_TRANS_BLOCKS(sb)-3)\
101		 +3+DQUOT_DEL_REWRITE) : 0)
102#else
103#define EXT4_QUOTA_TRANS_BLOCKS(sb) 0
104#define EXT4_QUOTA_INIT_BLOCKS(sb) 0
105#define EXT4_QUOTA_DEL_BLOCKS(sb) 0
106#endif
107#define EXT4_MAXQUOTAS_TRANS_BLOCKS(sb) (EXT4_MAXQUOTAS*EXT4_QUOTA_TRANS_BLOCKS(sb))
108#define EXT4_MAXQUOTAS_INIT_BLOCKS(sb) (EXT4_MAXQUOTAS*EXT4_QUOTA_INIT_BLOCKS(sb))
109#define EXT4_MAXQUOTAS_DEL_BLOCKS(sb) (EXT4_MAXQUOTAS*EXT4_QUOTA_DEL_BLOCKS(sb))
110
111/*
112 * Ext4 handle operation types -- for logging purposes
113 */
114#define EXT4_HT_MISC             0
115#define EXT4_HT_INODE            1
116#define EXT4_HT_WRITE_PAGE       2
117#define EXT4_HT_MAP_BLOCKS       3
118#define EXT4_HT_DIR              4
119#define EXT4_HT_TRUNCATE         5
120#define EXT4_HT_QUOTA            6
121#define EXT4_HT_RESIZE           7
122#define EXT4_HT_MIGRATE          8
123#define EXT4_HT_MOVE_EXTENTS     9
124#define EXT4_HT_XATTR           10
125#define EXT4_HT_EXT_CONVERT     11
126#define EXT4_HT_MAX             12
127
128/**
129 *   struct ext4_journal_cb_entry - Base structure for callback information.
130 *
131 *   This struct is a 'seed' structure for a using with your own callback
132 *   structs. If you are using callbacks you must allocate one of these
133 *   or another struct of your own definition which has this struct
134 *   as it's first element and pass it to ext4_journal_callback_add().
135 */
136struct ext4_journal_cb_entry {
137	/* list information for other callbacks attached to the same handle */
138	struct list_head jce_list;
139
140	/*  Function to call with this callback structure */
141	void (*jce_func)(struct super_block *sb,
142			 struct ext4_journal_cb_entry *jce, int error);
143
144	/* user data goes here */
145};
146
147/**
148 * ext4_journal_callback_add: add a function to call after transaction commit
149 * @handle: active journal transaction handle to register callback on
150 * @func: callback function to call after the transaction has committed:
151 *        @sb: superblock of current filesystem for transaction
152 *        @jce: returned journal callback data
153 *        @rc: journal state at commit (0 = transaction committed properly)
154 * @jce: journal callback data (internal and function private data struct)
155 *
156 * The registered function will be called in the context of the journal thread
157 * after the transaction for which the handle was created has completed.
158 *
159 * No locks are held when the callback function is called, so it is safe to
160 * call blocking functions from within the callback, but the callback should
161 * not block or run for too long, or the filesystem will be blocked waiting for
162 * the next transaction to commit. No journaling functions can be used, or
163 * there is a risk of deadlock.
164 *
165 * There is no guaranteed calling order of multiple registered callbacks on
166 * the same transaction.
167 */
168static inline void _ext4_journal_callback_add(handle_t *handle,
169			struct ext4_journal_cb_entry *jce)
170{
171	/* Add the jce to transaction's private list */
172	list_add_tail(&jce->jce_list, &handle->h_transaction->t_private_list);
173}
174
175static inline void ext4_journal_callback_add(handle_t *handle,
176			void (*func)(struct super_block *sb,
177				     struct ext4_journal_cb_entry *jce,
178				     int rc),
179			struct ext4_journal_cb_entry *jce)
180{
181	struct ext4_sb_info *sbi =
182			EXT4_SB(handle->h_transaction->t_journal->j_private);
183
184	/* Add the jce to transaction's private list */
185	jce->jce_func = func;
186	spin_lock(&sbi->s_md_lock);
187	_ext4_journal_callback_add(handle, jce);
188	spin_unlock(&sbi->s_md_lock);
189}
190
191
192/**
193 * ext4_journal_callback_del: delete a registered callback
194 * @handle: active journal transaction handle on which callback was registered
195 * @jce: registered journal callback entry to unregister
196 * Return true if object was successfully removed
197 */
198static inline bool ext4_journal_callback_try_del(handle_t *handle,
199					     struct ext4_journal_cb_entry *jce)
200{
201	bool deleted;
202	struct ext4_sb_info *sbi =
203			EXT4_SB(handle->h_transaction->t_journal->j_private);
204
205	spin_lock(&sbi->s_md_lock);
206	deleted = !list_empty(&jce->jce_list);
207	list_del_init(&jce->jce_list);
208	spin_unlock(&sbi->s_md_lock);
209	return deleted;
210}
211
212int
213ext4_mark_iloc_dirty(handle_t *handle,
214		     struct inode *inode,
215		     struct ext4_iloc *iloc);
216
217/*
218 * On success, We end up with an outstanding reference count against
219 * iloc->bh.  This _must_ be cleaned up later.
220 */
221
222int ext4_reserve_inode_write(handle_t *handle, struct inode *inode,
223			struct ext4_iloc *iloc);
224
225#define ext4_mark_inode_dirty(__h, __i)					\
226		__ext4_mark_inode_dirty((__h), (__i), __func__, __LINE__)
227int __ext4_mark_inode_dirty(handle_t *handle, struct inode *inode,
228				const char *func, unsigned int line);
229
230int ext4_expand_extra_isize(struct inode *inode,
231			    unsigned int new_extra_isize,
232			    struct ext4_iloc *iloc);
233/*
234 * Wrapper functions with which ext4 calls into JBD.
235 */
 
 
 
 
236int __ext4_journal_get_write_access(const char *where, unsigned int line,
237				    handle_t *handle, struct buffer_head *bh);
238
239int __ext4_forget(const char *where, unsigned int line, handle_t *handle,
240		  int is_metadata, struct inode *inode,
241		  struct buffer_head *bh, ext4_fsblk_t blocknr);
242
243int __ext4_journal_get_create_access(const char *where, unsigned int line,
244				handle_t *handle, struct buffer_head *bh);
245
246int __ext4_handle_dirty_metadata(const char *where, unsigned int line,
247				 handle_t *handle, struct inode *inode,
248				 struct buffer_head *bh);
249
250int __ext4_handle_dirty_super(const char *where, unsigned int line,
251			      handle_t *handle, struct super_block *sb);
 
252
253#define ext4_journal_get_write_access(handle, bh) \
254	__ext4_journal_get_write_access(__func__, __LINE__, (handle), (bh))
255#define ext4_forget(handle, is_metadata, inode, bh, block_nr) \
256	__ext4_forget(__func__, __LINE__, (handle), (is_metadata), (inode), \
257		      (bh), (block_nr))
258#define ext4_journal_get_create_access(handle, bh) \
259	__ext4_journal_get_create_access(__func__, __LINE__, (handle), (bh))
260#define ext4_handle_dirty_metadata(handle, inode, bh) \
261	__ext4_handle_dirty_metadata(__func__, __LINE__, (handle), (inode), \
262				     (bh))
 
 
263#define ext4_handle_dirty_super(handle, sb) \
264	__ext4_handle_dirty_super(__func__, __LINE__, (handle), (sb))
265
266handle_t *__ext4_journal_start_sb(struct super_block *sb, unsigned int line,
267				  int type, int blocks, int rsv_blocks,
268				  int revoke_creds);
269int __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. */
275static 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
282static inline void ext4_handle_sync(handle_t *handle)
283{
284	if (ext4_handle_valid(handle))
285		handle->h_sync = 1;
286}
287
 
 
 
 
 
 
 
288static 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
295static inline int ext4_free_metadata_revoke_credits(struct super_block *sb,
296						    int blocks)
297{
298	/* Freeing each metadata block can result in freeing one cluster */
299	return blocks * EXT4_SB(sb)->s_cluster_ratio;
300}
301
302static inline int ext4_trans_default_revoke_credits(struct super_block *sb)
303{
304	return ext4_free_metadata_revoke_credits(sb, 8);
305}
306
307#define ext4_journal_start_sb(sb, type, nblocks)			\
308	__ext4_journal_start_sb((sb), __LINE__, (type), (nblocks), 0,	\
309				ext4_trans_default_revoke_credits(sb))
310
311#define ext4_journal_start(inode, type, nblocks)			\
312	__ext4_journal_start((inode), __LINE__, (type), (nblocks), 0,	\
313			     ext4_trans_default_revoke_credits((inode)->i_sb))
314
315#define ext4_journal_start_with_reserve(inode, type, blocks, rsv_blocks)\
316	__ext4_journal_start((inode), __LINE__, (type), (blocks), (rsv_blocks),\
317			     ext4_trans_default_revoke_credits((inode)->i_sb))
318
319#define ext4_journal_start_with_revoke(inode, type, blocks, revoke_creds) \
320	__ext4_journal_start((inode), __LINE__, (type), (blocks), 0,	\
321			     (revoke_creds))
322
323static inline handle_t *__ext4_journal_start(struct inode *inode,
324					     unsigned int line, int type,
325					     int blocks, int rsv_blocks,
326					     int revoke_creds)
327{
328	return __ext4_journal_start_sb(inode->i_sb, line, type, blocks,
329				       rsv_blocks, revoke_creds);
330}
331
332#define ext4_journal_stop(handle) \
333	__ext4_journal_stop(__func__, __LINE__, (handle))
334
335#define ext4_journal_start_reserved(handle, type) \
336	__ext4_journal_start_reserved((handle), __LINE__, (type))
337
338handle_t *__ext4_journal_start_reserved(handle_t *handle, unsigned int line,
339					int type);
340
341static inline handle_t *ext4_journal_current_handle(void)
342{
343	return journal_current_handle();
344}
345
346static inline int ext4_journal_extend(handle_t *handle, int nblocks, int revoke)
347{
348	if (ext4_handle_valid(handle))
349		return jbd2_journal_extend(handle, nblocks, revoke);
350	return 0;
351}
352
353static inline int ext4_journal_restart(handle_t *handle, int nblocks,
354				       int revoke)
355{
356	if (ext4_handle_valid(handle))
357		return jbd2__journal_restart(handle, nblocks, revoke, GFP_NOFS);
358	return 0;
359}
360
361int __ext4_journal_ensure_credits(handle_t *handle, int check_cred,
362				  int extend_cred, int revoke_cred);
363
364
365/*
366 * Ensure @handle has at least @check_creds credits available. If not,
367 * transaction will be extended or restarted to contain at least @extend_cred
368 * credits. Before restarting transaction @fn is executed to allow for cleanup
369 * before the transaction is restarted.
370 *
371 * The return value is < 0 in case of error, 0 in case the handle has enough
372 * credits or transaction extension succeeded, 1 in case transaction had to be
373 * restarted.
374 */
375#define ext4_journal_ensure_credits_fn(handle, check_cred, extend_cred,	\
376				       revoke_cred, fn) \
377({									\
378	__label__ __ensure_end;						\
379	int err = __ext4_journal_ensure_credits((handle), (check_cred),	\
380					(extend_cred), (revoke_cred));	\
381									\
382	if (err <= 0)							\
383		goto __ensure_end;					\
384	err = (fn);							\
385	if (err < 0)							\
386		goto __ensure_end;					\
387	err = ext4_journal_restart((handle), (extend_cred), (revoke_cred)); \
388	if (err == 0)							\
389		err = 1;						\
390__ensure_end:								\
391	err;								\
392})
393
394/*
395 * Ensure given handle has at least requested amount of credits available,
396 * possibly restarting transaction if needed. We also make sure the transaction
397 * has space for at least ext4_trans_default_revoke_credits(sb) revoke records
398 * as freeing one or two blocks is very common pattern and requesting this is
399 * very cheap.
400 */
401static inline int ext4_journal_ensure_credits(handle_t *handle, int credits,
402					      int revoke_creds)
403{
404	return ext4_journal_ensure_credits_fn(handle, credits, credits,
405				revoke_creds, 0);
406}
407
408static inline int ext4_journal_blocks_per_page(struct inode *inode)
409{
410	if (EXT4_JOURNAL(inode) != NULL)
411		return jbd2_journal_blocks_per_page(inode);
412	return 0;
413}
414
415static inline int ext4_journal_force_commit(journal_t *journal)
416{
417	if (journal)
418		return jbd2_journal_force_commit(journal);
419	return 0;
420}
421
422static inline int ext4_jbd2_inode_add_write(handle_t *handle,
423		struct inode *inode, loff_t start_byte, loff_t length)
424{
425	if (ext4_handle_valid(handle))
426		return jbd2_journal_inode_ranged_write(handle,
427				EXT4_I(inode)->jinode, start_byte, length);
428	return 0;
429}
430
431static inline int ext4_jbd2_inode_add_wait(handle_t *handle,
432		struct inode *inode, loff_t start_byte, loff_t length)
433{
434	if (ext4_handle_valid(handle))
435		return jbd2_journal_inode_ranged_wait(handle,
436				EXT4_I(inode)->jinode, start_byte, length);
437	return 0;
438}
439
440static inline void ext4_update_inode_fsync_trans(handle_t *handle,
441						 struct inode *inode,
442						 int datasync)
443{
444	struct ext4_inode_info *ei = EXT4_I(inode);
445
446	if (ext4_handle_valid(handle) && !is_handle_aborted(handle)) {
447		ei->i_sync_tid = handle->h_transaction->t_tid;
448		if (datasync)
449			ei->i_datasync_tid = handle->h_transaction->t_tid;
450	}
451}
452
453/* super.c */
454int ext4_force_commit(struct super_block *sb);
455
456/*
457 * Ext4 inode journal modes
458 */
459#define EXT4_INODE_JOURNAL_DATA_MODE	0x01 /* journal data mode */
460#define EXT4_INODE_ORDERED_DATA_MODE	0x02 /* ordered data mode */
461#define EXT4_INODE_WRITEBACK_DATA_MODE	0x04 /* writeback data mode */
462
463int ext4_inode_journal_mode(struct inode *inode);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
464
465static inline int ext4_should_journal_data(struct inode *inode)
466{
467	return ext4_inode_journal_mode(inode) & EXT4_INODE_JOURNAL_DATA_MODE;
468}
469
470static inline int ext4_should_order_data(struct inode *inode)
471{
472	return ext4_inode_journal_mode(inode) & EXT4_INODE_ORDERED_DATA_MODE;
473}
474
475static inline int ext4_should_writeback_data(struct inode *inode)
476{
477	return ext4_inode_journal_mode(inode) & EXT4_INODE_WRITEBACK_DATA_MODE;
478}
479
480static inline int ext4_free_data_revoke_credits(struct inode *inode, int blocks)
481{
482	if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
483		return 0;
484	if (!ext4_should_journal_data(inode))
485		return 0;
486	/*
487	 * Data blocks in one extent are contiguous, just account for partial
488	 * clusters at extent boundaries
489	 */
490	return blocks + 2*(EXT4_SB(inode->i_sb)->s_cluster_ratio - 1);
491}
492
493/*
494 * This function controls whether or not we should try to go down the
495 * dioread_nolock code paths, which makes it safe to avoid taking
496 * i_mutex for direct I/O reads.  This only works for extent-based
497 * files, and it doesn't work if data journaling is enabled, since the
498 * dioread_nolock code uses b_private to pass information back to the
499 * I/O completion handler, and this conflicts with the jbd's use of
500 * b_private.
501 */
502static inline int ext4_should_dioread_nolock(struct inode *inode)
503{
504	if (!test_opt(inode->i_sb, DIOREAD_NOLOCK))
505		return 0;
506	if (!S_ISREG(inode->i_mode))
507		return 0;
508	if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
509		return 0;
510	if (ext4_should_journal_data(inode))
511		return 0;
512	/* temporary fix to prevent generic/422 test failures */
513	if (!test_opt(inode->i_sb, DELALLOC))
514		return 0;
515	return 1;
516}
517
518#endif	/* _EXT4_JBD2_H */