1 /*
2  * linux/include/linux/ext3_jbd.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  * Ext3-specific journaling extensions.
13  */
14 
15 #ifndef _LINUX_EXT3_JBD_H
16 #define _LINUX_EXT3_JBD_H
17 
18 #include <linux/fs.h>
19 #include <linux/jbd.h>
20 #include <linux/ext3_fs.h>
21 
22 #define EXT3_JOURNAL(inode)	(EXT3_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 #define EXT3_SINGLEDATA_TRANS_BLOCKS	8U
32 
33 /* Extended attribute operations touch at most two data buffers,
34  * two bitmap buffers, and two group summaries, in addition to the inode
35  * and the superblock, which are already accounted for. */
36 
37 #define EXT3_XATTR_TRANS_BLOCKS		6U
38 
39 /* Define the minimum size for a transaction which modifies data.  This
40  * needs to take into account the fact that we may end up modifying two
41  * quota files too (one for the group, one for the user quota).  The
42  * superblock only gets updated once, of course, so don't bother
43  * counting that again for the quota updates. */
44 
45 #define EXT3_DATA_TRANS_BLOCKS(sb)	(EXT3_SINGLEDATA_TRANS_BLOCKS + \
46 					 EXT3_XATTR_TRANS_BLOCKS - 2 + \
47 					 EXT3_MAXQUOTAS_TRANS_BLOCKS(sb))
48 
49 /* Delete operations potentially hit one directory's namespace plus an
50  * entire inode, plus arbitrary amounts of bitmap/indirection data.  Be
51  * generous.  We can grow the delete transaction later if necessary. */
52 
53 #define EXT3_DELETE_TRANS_BLOCKS(sb)   (EXT3_MAXQUOTAS_TRANS_BLOCKS(sb) + 64)
54 
55 /* Define an arbitrary limit for the amount of data we will anticipate
56  * writing to any given transaction.  For unbounded transactions such as
57  * write(2) and truncate(2) we can write more than this, but we always
58  * start off at the maximum transaction size and grow the transaction
59  * optimistically as we go. */
60 
61 #define EXT3_MAX_TRANS_DATA		64U
62 
63 /* We break up a large truncate or write transaction once the handle's
64  * buffer credits gets this low, we need either to extend the
65  * transaction or to start a new one.  Reserve enough space here for
66  * inode, bitmap, superblock, group and indirection updates for at least
67  * one block, plus two quota updates.  Quota allocations are not
68  * needed. */
69 
70 #define EXT3_RESERVE_TRANS_BLOCKS	12U
71 
72 #define EXT3_INDEX_EXTRA_TRANS_BLOCKS	8
73 
74 #ifdef CONFIG_QUOTA
75 /* Amount of blocks needed for quota update - we know that the structure was
76  * allocated so we need to update only inode+data */
77 #define EXT3_QUOTA_TRANS_BLOCKS(sb) (test_opt(sb, QUOTA) ? 2 : 0)
78 /* Amount of blocks needed for quota insert/delete - we do some block writes
79  * but inode, sb and group updates are done only once */
80 #define EXT3_QUOTA_INIT_BLOCKS(sb) (test_opt(sb, QUOTA) ? (DQUOT_INIT_ALLOC*\
81 		(EXT3_SINGLEDATA_TRANS_BLOCKS-3)+3+DQUOT_INIT_REWRITE) : 0)
82 #define EXT3_QUOTA_DEL_BLOCKS(sb) (test_opt(sb, QUOTA) ? (DQUOT_DEL_ALLOC*\
83 		(EXT3_SINGLEDATA_TRANS_BLOCKS-3)+3+DQUOT_DEL_REWRITE) : 0)
84 #else
85 #define EXT3_QUOTA_TRANS_BLOCKS(sb) 0
86 #define EXT3_QUOTA_INIT_BLOCKS(sb) 0
87 #define EXT3_QUOTA_DEL_BLOCKS(sb) 0
88 #endif
89 #define EXT3_MAXQUOTAS_TRANS_BLOCKS(sb) (MAXQUOTAS*EXT3_QUOTA_TRANS_BLOCKS(sb))
90 #define EXT3_MAXQUOTAS_INIT_BLOCKS(sb) (MAXQUOTAS*EXT3_QUOTA_INIT_BLOCKS(sb))
91 #define EXT3_MAXQUOTAS_DEL_BLOCKS(sb) (MAXQUOTAS*EXT3_QUOTA_DEL_BLOCKS(sb))
92 
93 int
94 ext3_mark_iloc_dirty(handle_t *handle,
95 		     struct inode *inode,
96 		     struct ext3_iloc *iloc);
97 
98 /*
99  * On success, We end up with an outstanding reference count against
100  * iloc->bh.  This _must_ be cleaned up later.
101  */
102 
103 int ext3_reserve_inode_write(handle_t *handle, struct inode *inode,
104 			struct ext3_iloc *iloc);
105 
106 int ext3_mark_inode_dirty(handle_t *handle, struct inode *inode);
107 
108 /*
109  * Wrapper functions with which ext3 calls into JBD.  The intent here is
110  * to allow these to be turned into appropriate stubs so ext3 can control
111  * ext2 filesystems, so ext2+ext3 systems only nee one fs.  This work hasn't
112  * been done yet.
113  */
114 
ext3_journal_release_buffer(handle_t * handle,struct buffer_head * bh)115 static inline void ext3_journal_release_buffer(handle_t *handle,
116 						struct buffer_head *bh)
117 {
118 	journal_release_buffer(handle, bh);
119 }
120 
121 void ext3_journal_abort_handle(const char *caller, const char *err_fn,
122 		struct buffer_head *bh, handle_t *handle, int err);
123 
124 int __ext3_journal_get_undo_access(const char *where, handle_t *handle,
125 				struct buffer_head *bh);
126 
127 int __ext3_journal_get_write_access(const char *where, handle_t *handle,
128 				struct buffer_head *bh);
129 
130 int __ext3_journal_forget(const char *where, handle_t *handle,
131 				struct buffer_head *bh);
132 
133 int __ext3_journal_revoke(const char *where, handle_t *handle,
134 				unsigned long blocknr, struct buffer_head *bh);
135 
136 int __ext3_journal_get_create_access(const char *where,
137 				handle_t *handle, struct buffer_head *bh);
138 
139 int __ext3_journal_dirty_metadata(const char *where,
140 				handle_t *handle, struct buffer_head *bh);
141 
142 #define ext3_journal_get_undo_access(handle, bh) \
143 	__ext3_journal_get_undo_access(__func__, (handle), (bh))
144 #define ext3_journal_get_write_access(handle, bh) \
145 	__ext3_journal_get_write_access(__func__, (handle), (bh))
146 #define ext3_journal_revoke(handle, blocknr, bh) \
147 	__ext3_journal_revoke(__func__, (handle), (blocknr), (bh))
148 #define ext3_journal_get_create_access(handle, bh) \
149 	__ext3_journal_get_create_access(__func__, (handle), (bh))
150 #define ext3_journal_dirty_metadata(handle, bh) \
151 	__ext3_journal_dirty_metadata(__func__, (handle), (bh))
152 #define ext3_journal_forget(handle, bh) \
153 	__ext3_journal_forget(__func__, (handle), (bh))
154 
155 int ext3_journal_dirty_data(handle_t *handle, struct buffer_head *bh);
156 
157 handle_t *ext3_journal_start_sb(struct super_block *sb, int nblocks);
158 int __ext3_journal_stop(const char *where, handle_t *handle);
159 
ext3_journal_start(struct inode * inode,int nblocks)160 static inline handle_t *ext3_journal_start(struct inode *inode, int nblocks)
161 {
162 	return ext3_journal_start_sb(inode->i_sb, nblocks);
163 }
164 
165 #define ext3_journal_stop(handle) \
166 	__ext3_journal_stop(__func__, (handle))
167 
ext3_journal_current_handle(void)168 static inline handle_t *ext3_journal_current_handle(void)
169 {
170 	return journal_current_handle();
171 }
172 
ext3_journal_extend(handle_t * handle,int nblocks)173 static inline int ext3_journal_extend(handle_t *handle, int nblocks)
174 {
175 	return journal_extend(handle, nblocks);
176 }
177 
ext3_journal_restart(handle_t * handle,int nblocks)178 static inline int ext3_journal_restart(handle_t *handle, int nblocks)
179 {
180 	return journal_restart(handle, nblocks);
181 }
182 
ext3_journal_blocks_per_page(struct inode * inode)183 static inline int ext3_journal_blocks_per_page(struct inode *inode)
184 {
185 	return journal_blocks_per_page(inode);
186 }
187 
ext3_journal_force_commit(journal_t * journal)188 static inline int ext3_journal_force_commit(journal_t *journal)
189 {
190 	return journal_force_commit(journal);
191 }
192 
193 /* super.c */
194 int ext3_force_commit(struct super_block *sb);
195 
ext3_should_journal_data(struct inode * inode)196 static inline int ext3_should_journal_data(struct inode *inode)
197 {
198 	if (!S_ISREG(inode->i_mode))
199 		return 1;
200 	if (test_opt(inode->i_sb, DATA_FLAGS) == EXT3_MOUNT_JOURNAL_DATA)
201 		return 1;
202 	if (EXT3_I(inode)->i_flags & EXT3_JOURNAL_DATA_FL)
203 		return 1;
204 	return 0;
205 }
206 
ext3_should_order_data(struct inode * inode)207 static inline int ext3_should_order_data(struct inode *inode)
208 {
209 	if (!S_ISREG(inode->i_mode))
210 		return 0;
211 	if (EXT3_I(inode)->i_flags & EXT3_JOURNAL_DATA_FL)
212 		return 0;
213 	if (test_opt(inode->i_sb, DATA_FLAGS) == EXT3_MOUNT_ORDERED_DATA)
214 		return 1;
215 	return 0;
216 }
217 
ext3_should_writeback_data(struct inode * inode)218 static inline int ext3_should_writeback_data(struct inode *inode)
219 {
220 	if (!S_ISREG(inode->i_mode))
221 		return 0;
222 	if (EXT3_I(inode)->i_flags & EXT3_JOURNAL_DATA_FL)
223 		return 0;
224 	if (test_opt(inode->i_sb, DATA_FLAGS) == EXT3_MOUNT_WRITEBACK_DATA)
225 		return 1;
226 	return 0;
227 }
228 
229 #endif	/* _LINUX_EXT3_JBD_H */
230