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 int
108 ext4_mark_iloc_dirty(handle_t *handle,
109 struct inode *inode,
110 struct ext4_iloc *iloc);
111
112 /*
113 * On success, We end up with an outstanding reference count against
114 * iloc->bh. This _must_ be cleaned up later.
115 */
116
117 int ext4_reserve_inode_write(handle_t *handle, struct inode *inode,
118 struct ext4_iloc *iloc);
119
120 int ext4_mark_inode_dirty(handle_t *handle, struct inode *inode);
121
122 /*
123 * Wrapper functions with which ext4 calls into JBD.
124 */
125 void ext4_journal_abort_handle(const char *caller, unsigned int line,
126 const char *err_fn,
127 struct buffer_head *bh, handle_t *handle, int err);
128
129 int __ext4_journal_get_undo_access(const char *where, unsigned int line,
130 handle_t *handle, struct buffer_head *bh);
131
132 int __ext4_journal_get_write_access(const char *where, unsigned int line,
133 handle_t *handle, struct buffer_head *bh);
134
135 int __ext4_forget(const char *where, unsigned int line, handle_t *handle,
136 int is_metadata, struct inode *inode,
137 struct buffer_head *bh, ext4_fsblk_t blocknr);
138
139 int __ext4_journal_get_create_access(const char *where, unsigned int line,
140 handle_t *handle, struct buffer_head *bh);
141
142 int __ext4_handle_dirty_metadata(const char *where, unsigned int line,
143 handle_t *handle, struct inode *inode,
144 struct buffer_head *bh);
145
146 int __ext4_handle_dirty_super(const char *where, unsigned int line,
147 handle_t *handle, struct super_block *sb);
148
149 #define ext4_journal_get_undo_access(handle, bh) \
150 __ext4_journal_get_undo_access(__func__, __LINE__, (handle), (bh))
151 #define ext4_journal_get_write_access(handle, bh) \
152 __ext4_journal_get_write_access(__func__, __LINE__, (handle), (bh))
153 #define ext4_forget(handle, is_metadata, inode, bh, block_nr) \
154 __ext4_forget(__func__, __LINE__, (handle), (is_metadata), (inode), \
155 (bh), (block_nr))
156 #define ext4_journal_get_create_access(handle, bh) \
157 __ext4_journal_get_create_access(__func__, __LINE__, (handle), (bh))
158 #define ext4_handle_dirty_metadata(handle, inode, bh) \
159 __ext4_handle_dirty_metadata(__func__, __LINE__, (handle), (inode), \
160 (bh))
161 #define ext4_handle_dirty_super(handle, sb) \
162 __ext4_handle_dirty_super(__func__, __LINE__, (handle), (sb))
163
164 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks);
165 int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle);
166
167 #define EXT4_NOJOURNAL_MAX_REF_COUNT ((unsigned long) 4096)
168
169 /* Note: Do not use this for NULL handles. This is only to determine if
170 * a properly allocated handle is using a journal or not. */
ext4_handle_valid(handle_t * handle)171 static inline int ext4_handle_valid(handle_t *handle)
172 {
173 if ((unsigned long)handle < EXT4_NOJOURNAL_MAX_REF_COUNT)
174 return 0;
175 return 1;
176 }
177
ext4_handle_sync(handle_t * handle)178 static inline void ext4_handle_sync(handle_t *handle)
179 {
180 if (ext4_handle_valid(handle))
181 handle->h_sync = 1;
182 }
183
ext4_handle_release_buffer(handle_t * handle,struct buffer_head * bh)184 static inline void ext4_handle_release_buffer(handle_t *handle,
185 struct buffer_head *bh)
186 {
187 if (ext4_handle_valid(handle))
188 jbd2_journal_release_buffer(handle, bh);
189 }
190
ext4_handle_is_aborted(handle_t * handle)191 static inline int ext4_handle_is_aborted(handle_t *handle)
192 {
193 if (ext4_handle_valid(handle))
194 return is_handle_aborted(handle);
195 return 0;
196 }
197
ext4_handle_has_enough_credits(handle_t * handle,int needed)198 static inline int ext4_handle_has_enough_credits(handle_t *handle, int needed)
199 {
200 if (ext4_handle_valid(handle) && handle->h_buffer_credits < needed)
201 return 0;
202 return 1;
203 }
204
ext4_journal_start(struct inode * inode,int nblocks)205 static inline handle_t *ext4_journal_start(struct inode *inode, int nblocks)
206 {
207 return ext4_journal_start_sb(inode->i_sb, nblocks);
208 }
209
210 #define ext4_journal_stop(handle) \
211 __ext4_journal_stop(__func__, __LINE__, (handle))
212
ext4_journal_current_handle(void)213 static inline handle_t *ext4_journal_current_handle(void)
214 {
215 return journal_current_handle();
216 }
217
ext4_journal_extend(handle_t * handle,int nblocks)218 static inline int ext4_journal_extend(handle_t *handle, int nblocks)
219 {
220 if (ext4_handle_valid(handle))
221 return jbd2_journal_extend(handle, nblocks);
222 return 0;
223 }
224
ext4_journal_restart(handle_t * handle,int nblocks)225 static inline int ext4_journal_restart(handle_t *handle, int nblocks)
226 {
227 if (ext4_handle_valid(handle))
228 return jbd2_journal_restart(handle, nblocks);
229 return 0;
230 }
231
ext4_journal_blocks_per_page(struct inode * inode)232 static inline int ext4_journal_blocks_per_page(struct inode *inode)
233 {
234 if (EXT4_JOURNAL(inode) != NULL)
235 return jbd2_journal_blocks_per_page(inode);
236 return 0;
237 }
238
ext4_journal_force_commit(journal_t * journal)239 static inline int ext4_journal_force_commit(journal_t *journal)
240 {
241 if (journal)
242 return jbd2_journal_force_commit(journal);
243 return 0;
244 }
245
ext4_jbd2_file_inode(handle_t * handle,struct inode * inode)246 static inline int ext4_jbd2_file_inode(handle_t *handle, struct inode *inode)
247 {
248 if (ext4_handle_valid(handle))
249 return jbd2_journal_file_inode(handle, EXT4_I(inode)->jinode);
250 return 0;
251 }
252
ext4_update_inode_fsync_trans(handle_t * handle,struct inode * inode,int datasync)253 static inline void ext4_update_inode_fsync_trans(handle_t *handle,
254 struct inode *inode,
255 int datasync)
256 {
257 struct ext4_inode_info *ei = EXT4_I(inode);
258
259 if (ext4_handle_valid(handle)) {
260 ei->i_sync_tid = handle->h_transaction->t_tid;
261 if (datasync)
262 ei->i_datasync_tid = handle->h_transaction->t_tid;
263 }
264 }
265
266 /* super.c */
267 int ext4_force_commit(struct super_block *sb);
268
ext4_should_journal_data(struct inode * inode)269 static inline int ext4_should_journal_data(struct inode *inode)
270 {
271 if (EXT4_JOURNAL(inode) == NULL)
272 return 0;
273 if (!S_ISREG(inode->i_mode))
274 return 1;
275 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
276 return 1;
277 if (ext4_test_inode_flag(inode, EXT4_INODE_JOURNAL_DATA))
278 return 1;
279 return 0;
280 }
281
ext4_should_order_data(struct inode * inode)282 static inline int ext4_should_order_data(struct inode *inode)
283 {
284 if (EXT4_JOURNAL(inode) == NULL)
285 return 0;
286 if (!S_ISREG(inode->i_mode))
287 return 0;
288 if (ext4_test_inode_flag(inode, EXT4_INODE_JOURNAL_DATA))
289 return 0;
290 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
291 return 1;
292 return 0;
293 }
294
ext4_should_writeback_data(struct inode * inode)295 static inline int ext4_should_writeback_data(struct inode *inode)
296 {
297 if (!S_ISREG(inode->i_mode))
298 return 0;
299 if (EXT4_JOURNAL(inode) == NULL)
300 return 1;
301 if (ext4_test_inode_flag(inode, EXT4_INODE_JOURNAL_DATA))
302 return 0;
303 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
304 return 1;
305 return 0;
306 }
307
308 /*
309 * This function controls whether or not we should try to go down the
310 * dioread_nolock code paths, which makes it safe to avoid taking
311 * i_mutex for direct I/O reads. This only works for extent-based
312 * files, and it doesn't work if data journaling is enabled, since the
313 * dioread_nolock code uses b_private to pass information back to the
314 * I/O completion handler, and this conflicts with the jbd's use of
315 * b_private.
316 */
ext4_should_dioread_nolock(struct inode * inode)317 static inline int ext4_should_dioread_nolock(struct inode *inode)
318 {
319 if (!test_opt(inode->i_sb, DIOREAD_NOLOCK))
320 return 0;
321 if (!S_ISREG(inode->i_mode))
322 return 0;
323 if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
324 return 0;
325 if (ext4_should_journal_data(inode))
326 return 0;
327 return 1;
328 }
329
330 #endif /* _EXT4_JBD2_H */
331