include/linux/ext3_jbd.h

   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                                          2*EXT3_QUOTA_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)    (2 * EXT3_DATA_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
  90 int
  91 ext3_mark_iloc_dirty(handle_t *handle,
  92                      struct inode *inode,
  93                      struct ext3_iloc *iloc);
  94
  95 /*
  96  * On success, We end up with an outstanding reference count against
  97  * iloc->bh.  This _must_ be cleaned up later.
  98  */
  99
 100 int ext3_reserve_inode_write(handle_t *handle, struct inode *inode,
 101                         struct ext3_iloc *iloc);
 102
 103 int ext3_mark_inode_dirty(handle_t *handle, struct inode *inode);
 104
 105 /*
 106  * Wrapper functions with which ext3 calls into JBD.  The intent here is
 107  * to allow these to be turned into appropriate stubs so ext3 can control
 108  * ext2 filesystems, so ext2+ext3 systems only nee one fs.  This work hasn't
 109  * been done yet.
 110  */
 111
 112 static inline void ext3_journal_release_buffer(handle_t *handle,
 113                                                 struct buffer_head *bh)
 114 {
 115         journal_release_buffer(handle, bh);
 116 }
 117
 118 void ext3_journal_abort_handle(const char *caller, const char *err_fn,
 119                 struct buffer_head *bh, handle_t *handle, int err);
 120
 121 int __ext3_journal_get_undo_access(const char *where, handle_t *handle,
 122                                 struct buffer_head *bh);
 123
 124 int __ext3_journal_get_write_access(const char *where, handle_t *handle,
 125                                 struct buffer_head *bh);
 126
 127 int __ext3_journal_forget(const char *where, handle_t *handle,
 128                                 struct buffer_head *bh);
 129
 130 int __ext3_journal_revoke(const char *where, handle_t *handle,
 131                                 unsigned long blocknr, struct buffer_head *bh);
 132
 133 int __ext3_journal_get_create_access(const char *where,
 134                                 handle_t *handle, struct buffer_head *bh);
 135
 136 int __ext3_journal_dirty_metadata(const char *where,
 137                                 handle_t *handle, struct buffer_head *bh);
 138
 139 #define ext3_journal_get_undo_access(handle, bh) \
 140         __ext3_journal_get_undo_access(__func__, (handle), (bh))
 141 #define ext3_journal_get_write_access(handle, bh) \
 142         __ext3_journal_get_write_access(__func__, (handle), (bh))
 143 #define ext3_journal_revoke(handle, blocknr, bh) \
 144         __ext3_journal_revoke(__func__, (handle), (blocknr), (bh))
 145 #define ext3_journal_get_create_access(handle, bh) \
 146         __ext3_journal_get_create_access(__func__, (handle), (bh))
 147 #define ext3_journal_dirty_metadata(handle, bh) \
 148         __ext3_journal_dirty_metadata(__func__, (handle), (bh))
 149 #define ext3_journal_forget(handle, bh) \
 150         __ext3_journal_forget(__func__, (handle), (bh))
 151
 152 int ext3_journal_dirty_data(handle_t *handle, struct buffer_head *bh);
 153
 154 handle_t *ext3_journal_start_sb(struct super_block *sb, int nblocks);
 155 int __ext3_journal_stop(const char *where, handle_t *handle);
 156
 157 static inline handle_t *ext3_journal_start(struct inode *inode, int nblocks)
 158 {
 159         return ext3_journal_start_sb(inode->i_sb, nblocks);
 160 }
 161
 162 #define ext3_journal_stop(handle) \
 163         __ext3_journal_stop(__func__, (handle))
 164
 165 static inline handle_t *ext3_journal_current_handle(void)
 166 {
 167         return journal_current_handle();
 168 }
 169
 170 static inline int ext3_journal_extend(handle_t *handle, int nblocks)
 171 {
 172         return journal_extend(handle, nblocks);
 173 }
 174
 175 static inline int ext3_journal_restart(handle_t *handle, int nblocks)
 176 {
 177         return journal_restart(handle, nblocks);
 178 }
 179
 180 static inline int ext3_journal_blocks_per_page(struct inode *inode)
 181 {
 182         return journal_blocks_per_page(inode);
 183 }
 184
 185 static inline int ext3_journal_force_commit(journal_t *journal)
 186 {
 187         return journal_force_commit(journal);
 188 }
 189
 190 /* super.c */
 191 int ext3_force_commit(struct super_block *sb);
 192
 193 static inline int ext3_should_journal_data(struct inode *inode)
 194 {
 195         if (!S_ISREG(inode->i_mode))
 196                 return 1;
 197         if (test_opt(inode->i_sb, DATA_FLAGS) == EXT3_MOUNT_JOURNAL_DATA)
 198                 return 1;
 199         if (EXT3_I(inode)->i_flags & EXT3_JOURNAL_DATA_FL)
 200                 return 1;
 201         return 0;
 202 }
 203
 204 static inline int ext3_should_order_data(struct inode *inode)
 205 {
 206         if (!S_ISREG(inode->i_mode))
 207                 return 0;
 208         if (EXT3_I(inode)->i_flags & EXT3_JOURNAL_DATA_FL)
 209                 return 0;
 210         if (test_opt(inode->i_sb, DATA_FLAGS) == EXT3_MOUNT_ORDERED_DATA)
 211                 return 1;
 212         return 0;
 213 }
 214
 215 static inline int ext3_should_writeback_data(struct inode *inode)
 216 {
 217         if (!S_ISREG(inode->i_mode))
 218                 return 0;
 219         if (EXT3_I(inode)->i_flags & EXT3_JOURNAL_DATA_FL)
 220                 return 0;
 221         if (test_opt(inode->i_sb, DATA_FLAGS) == EXT3_MOUNT_WRITEBACK_DATA)
 222                 return 1;
 223         return 0;
 224 }
 225
 226 #endif  /* _LINUX_EXT3_JBD_H */