include/linux/ext4_jbd2.h

   1 /*
   2  * linux/include/linux/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 _LINUX_EXT4_JBD2_H
  16 #define _LINUX_EXT4_JBD2_H
  17
  18 #include <linux/fs.h>
  19 #include <linux/jbd2.h>
  20 #include <linux/ext4_fs.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                 || test_opt(sb, EXTENTS) ? 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                                          2*EXT4_QUOTA_TRANS_BLOCKS(sb))
  53
  54 /* Delete operations potentially hit one directory's namespace plus an
  55  * entire inode, plus arbitrary amounts of bitmap/indirection data.  Be
  56  * generous.  We can grow the delete transaction later if necessary. */
  57
  58 #define EXT4_DELETE_TRANS_BLOCKS(sb)    (2 * EXT4_DATA_TRANS_BLOCKS(sb) + 64)
  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 #define EXT4_INDEX_EXTRA_TRANS_BLOCKS   8
  78
  79 #ifdef CONFIG_QUOTA
  80 /* Amount of blocks needed for quota update - we know that the structure was
  81  * allocated so we need to update only inode+data */
  82 #define EXT4_QUOTA_TRANS_BLOCKS(sb) (test_opt(sb, QUOTA) ? 2 : 0)
  83 /* Amount of blocks needed for quota insert/delete - we do some block writes
  84  * but inode, sb and group updates are done only once */
  85 #define EXT4_QUOTA_INIT_BLOCKS(sb) (test_opt(sb, QUOTA) ? (DQUOT_INIT_ALLOC*\
  86                 (EXT4_SINGLEDATA_TRANS_BLOCKS(sb)-3)+3+DQUOT_INIT_REWRITE) : 0)
  87 #define EXT4_QUOTA_DEL_BLOCKS(sb) (test_opt(sb, QUOTA) ? (DQUOT_DEL_ALLOC*\
  88                 (EXT4_SINGLEDATA_TRANS_BLOCKS(sb)-3)+3+DQUOT_DEL_REWRITE) : 0)
  89 #else
  90 #define EXT4_QUOTA_TRANS_BLOCKS(sb) 0
  91 #define EXT4_QUOTA_INIT_BLOCKS(sb) 0
  92 #define EXT4_QUOTA_DEL_BLOCKS(sb) 0
  93 #endif
  94
  95 int
  96 ext4_mark_iloc_dirty(handle_t *handle,
  97                      struct inode *inode,
  98                      struct ext4_iloc *iloc);
  99
 100 /*
 101  * On success, We end up with an outstanding reference count against
 102  * iloc->bh.  This _must_ be cleaned up later.
 103  */
 104
 105 int ext4_reserve_inode_write(handle_t *handle, struct inode *inode,
 106                         struct ext4_iloc *iloc);
 107
 108 int ext4_mark_inode_dirty(handle_t *handle, struct inode *inode);
 109
 110 /*
 111  * Wrapper functions with which ext4 calls into JBD.  The intent here is
 112  * to allow these to be turned into appropriate stubs so ext4 can control
 113  * ext2 filesystems, so ext2+ext4 systems only nee one fs.  This work hasn't
 114  * been done yet.
 115  */
 116
 117 static inline void ext4_journal_release_buffer(handle_t *handle,
 118                                                 struct buffer_head *bh)
 119 {
 120         jbd2_journal_release_buffer(handle, bh);
 121 }
 122
 123 void ext4_journal_abort_handle(const char *caller, const char *err_fn,
 124                 struct buffer_head *bh, handle_t *handle, int err);
 125
 126 int __ext4_journal_get_undo_access(const char *where, handle_t *handle,
 127                                 struct buffer_head *bh);
 128
 129 int __ext4_journal_get_write_access(const char *where, handle_t *handle,
 130                                 struct buffer_head *bh);
 131
 132 int __ext4_journal_forget(const char *where, handle_t *handle,
 133                                 struct buffer_head *bh);
 134
 135 int __ext4_journal_revoke(const char *where, handle_t *handle,
 136                                 ext4_fsblk_t blocknr, struct buffer_head *bh);
 137
 138 int __ext4_journal_get_create_access(const char *where,
 139                                 handle_t *handle, struct buffer_head *bh);
 140
 141 int __ext4_journal_dirty_metadata(const char *where,
 142                                 handle_t *handle, struct buffer_head *bh);
 143
 144 #define ext4_journal_get_undo_access(handle, bh) \
 145         __ext4_journal_get_undo_access(__FUNCTION__, (handle), (bh))
 146 #define ext4_journal_get_write_access(handle, bh) \
 147         __ext4_journal_get_write_access(__FUNCTION__, (handle), (bh))
 148 #define ext4_journal_revoke(handle, blocknr, bh) \
 149         __ext4_journal_revoke(__FUNCTION__, (handle), (blocknr), (bh))
 150 #define ext4_journal_get_create_access(handle, bh) \
 151         __ext4_journal_get_create_access(__FUNCTION__, (handle), (bh))
 152 #define ext4_journal_dirty_metadata(handle, bh) \
 153         __ext4_journal_dirty_metadata(__FUNCTION__, (handle), (bh))
 154 #define ext4_journal_forget(handle, bh) \
 155         __ext4_journal_forget(__FUNCTION__, (handle), (bh))
 156
 157 int ext4_journal_dirty_data(handle_t *handle, struct buffer_head *bh);
 158
 159 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks);
 160 int __ext4_journal_stop(const char *where, handle_t *handle);
 161
 162 static inline handle_t *ext4_journal_start(struct inode *inode, int nblocks)
 163 {
 164         return ext4_journal_start_sb(inode->i_sb, nblocks);
 165 }
 166
 167 #define ext4_journal_stop(handle) \
 168         __ext4_journal_stop(__FUNCTION__, (handle))
 169
 170 static inline handle_t *ext4_journal_current_handle(void)
 171 {
 172         return journal_current_handle();
 173 }
 174
 175 static inline int ext4_journal_extend(handle_t *handle, int nblocks)
 176 {
 177         return jbd2_journal_extend(handle, nblocks);
 178 }
 179
 180 static inline int ext4_journal_restart(handle_t *handle, int nblocks)
 181 {
 182         return jbd2_journal_restart(handle, nblocks);
 183 }
 184
 185 static inline int ext4_journal_blocks_per_page(struct inode *inode)
 186 {
 187         return jbd2_journal_blocks_per_page(inode);
 188 }
 189
 190 static inline int ext4_journal_force_commit(journal_t *journal)
 191 {
 192         return jbd2_journal_force_commit(journal);
 193 }
 194
 195 /* super.c */
 196 int ext4_force_commit(struct super_block *sb);
 197
 198 static inline int ext4_should_journal_data(struct inode *inode)
 199 {
 200         if (!S_ISREG(inode->i_mode))
 201                 return 1;
 202         if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
 203                 return 1;
 204         if (EXT4_I(inode)->i_flags & EXT4_JOURNAL_DATA_FL)
 205                 return 1;
 206         return 0;
 207 }
 208
 209 static inline int ext4_should_order_data(struct inode *inode)
 210 {
 211         if (!S_ISREG(inode->i_mode))
 212                 return 0;
 213         if (EXT4_I(inode)->i_flags & EXT4_JOURNAL_DATA_FL)
 214                 return 0;
 215         if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
 216                 return 1;
 217         return 0;
 218 }
 219
 220 static inline int ext4_should_writeback_data(struct inode *inode)
 221 {
 222         if (!S_ISREG(inode->i_mode))
 223                 return 0;
 224         if (EXT4_I(inode)->i_flags & EXT4_JOURNAL_DATA_FL)
 225                 return 0;
 226         if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
 227                 return 1;
 228         return 0;
 229 }
 230
 231 #endif  /* _LINUX_EXT4_JBD2_H */