fs/ext4/ext4_jbd2.h

   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 inode+data */
  90 #define EXT4_QUOTA_TRANS_BLOCKS(sb) (test_opt(sb, QUOTA) ? 2 : 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.  The intent here is
 124  * to allow these to be turned into appropriate stubs so ext4 can control
 125  * ext2 filesystems, so ext2+ext4 systems only nee one fs.  This work hasn't
 126  * been done yet.
 127  */
 128
 129 void ext4_journal_abort_handle(const char *caller, const char *err_fn,
 130                 struct buffer_head *bh, handle_t *handle, int err);
 131
 132 int __ext4_journal_get_undo_access(const char *where, handle_t *handle,
 133                                 struct buffer_head *bh);
 134
 135 int __ext4_journal_get_write_access(const char *where, handle_t *handle,
 136                                 struct buffer_head *bh);
 137
 138 /* When called with an invalid handle, this will still do a put on the BH */
 139 int __ext4_journal_forget(const char *where, handle_t *handle,
 140                                 struct buffer_head *bh);
 141
 142 /* When called with an invalid handle, this will still do a put on the BH */
 143 int __ext4_journal_revoke(const char *where, handle_t *handle,
 144                                 ext4_fsblk_t blocknr, struct buffer_head *bh);
 145
 146 int __ext4_journal_get_create_access(const char *where,
 147                                 handle_t *handle, struct buffer_head *bh);
 148
 149 int __ext4_handle_dirty_metadata(const char *where, handle_t *handle,
 150                                  struct inode *inode, struct buffer_head *bh);
 151
 152 #define ext4_journal_get_undo_access(handle, bh) \
 153         __ext4_journal_get_undo_access(__func__, (handle), (bh))
 154 #define ext4_journal_get_write_access(handle, bh) \
 155         __ext4_journal_get_write_access(__func__, (handle), (bh))
 156 #define ext4_journal_revoke(handle, blocknr, bh) \
 157         __ext4_journal_revoke(__func__, (handle), (blocknr), (bh))
 158 #define ext4_journal_get_create_access(handle, bh) \
 159         __ext4_journal_get_create_access(__func__, (handle), (bh))
 160 #define ext4_journal_forget(handle, bh) \
 161         __ext4_journal_forget(__func__, (handle), (bh))
 162 #define ext4_handle_dirty_metadata(handle, inode, bh) \
 163         __ext4_handle_dirty_metadata(__func__, (handle), (inode), (bh))
 164
 165 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks);
 166 int __ext4_journal_stop(const char *where, handle_t *handle);
 167
 168 #define EXT4_NOJOURNAL_MAX_REF_COUNT ((unsigned long) 4096)
 169
 170 /* Note:  Do not use this for NULL handles.  This is only to determine if
 171  * a properly allocated handle is using a journal or not. */
 172 static inline int ext4_handle_valid(handle_t *handle)
 173 {
 174         if ((unsigned long)handle < EXT4_NOJOURNAL_MAX_REF_COUNT)
 175                 return 0;
 176         return 1;
 177 }
 178
 179 static inline void ext4_handle_sync(handle_t *handle)
 180 {
 181         if (ext4_handle_valid(handle))
 182                 handle->h_sync = 1;
 183 }
 184
 185 static inline void ext4_handle_release_buffer(handle_t *handle,
 186                                                 struct buffer_head *bh)
 187 {
 188         if (ext4_handle_valid(handle))
 189                 jbd2_journal_release_buffer(handle, bh);
 190 }
 191
 192 static inline int ext4_handle_is_aborted(handle_t *handle)
 193 {
 194         if (ext4_handle_valid(handle))
 195                 return is_handle_aborted(handle);
 196         return 0;
 197 }
 198
 199 static inline int ext4_handle_has_enough_credits(handle_t *handle, int needed)
 200 {
 201         if (ext4_handle_valid(handle) && handle->h_buffer_credits < needed)
 202                 return 0;
 203         return 1;
 204 }
 205
 206 static inline void ext4_journal_release_buffer(handle_t *handle,
 207                                                 struct buffer_head *bh)
 208 {
 209         if (ext4_handle_valid(handle))
 210                 jbd2_journal_release_buffer(handle, bh);
 211 }
 212
 213 static inline handle_t *ext4_journal_start(struct inode *inode, int nblocks)
 214 {
 215         return ext4_journal_start_sb(inode->i_sb, nblocks);
 216 }
 217
 218 #define ext4_journal_stop(handle) \
 219         __ext4_journal_stop(__func__, (handle))
 220
 221 static inline handle_t *ext4_journal_current_handle(void)
 222 {
 223         return journal_current_handle();
 224 }
 225
 226 static inline int ext4_journal_extend(handle_t *handle, int nblocks)
 227 {
 228         if (ext4_handle_valid(handle))
 229                 return jbd2_journal_extend(handle, nblocks);
 230         return 0;
 231 }
 232
 233 static inline int ext4_journal_restart(handle_t *handle, int nblocks)
 234 {
 235         if (ext4_handle_valid(handle))
 236                 return jbd2_journal_restart(handle, nblocks);
 237         return 0;
 238 }
 239
 240 static inline int ext4_journal_blocks_per_page(struct inode *inode)
 241 {
 242         if (EXT4_JOURNAL(inode) != NULL)
 243                 return jbd2_journal_blocks_per_page(inode);
 244         return 0;
 245 }
 246
 247 static inline int ext4_journal_force_commit(journal_t *journal)
 248 {
 249         if (journal)
 250                 return jbd2_journal_force_commit(journal);
 251         return 0;
 252 }
 253
 254 static inline int ext4_jbd2_file_inode(handle_t *handle, struct inode *inode)
 255 {
 256         if (ext4_handle_valid(handle))
 257                 return jbd2_journal_file_inode(handle, &EXT4_I(inode)->jinode);
 258         return 0;
 259 }
 260
 261 static inline void ext4_update_inode_fsync_trans(handle_t *handle,
 262                                                  struct inode *inode,
 263                                                  int datasync)
 264 {
 265         struct ext4_inode_info *ei = EXT4_I(inode);
 266
 267         if (ext4_handle_valid(handle)) {
 268                 ei->i_sync_tid = handle->h_transaction->t_tid;
 269                 if (datasync)
 270                         ei->i_datasync_tid = handle->h_transaction->t_tid;
 271         }
 272 }
 273
 274 /* super.c */
 275 int ext4_force_commit(struct super_block *sb);
 276
 277 static inline int ext4_should_journal_data(struct inode *inode)
 278 {
 279         if (EXT4_JOURNAL(inode) == NULL)
 280                 return 0;
 281         if (!S_ISREG(inode->i_mode))
 282                 return 1;
 283         if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
 284                 return 1;
 285         if (EXT4_I(inode)->i_flags & EXT4_JOURNAL_DATA_FL)
 286                 return 1;
 287         return 0;
 288 }
 289
 290 static inline int ext4_should_order_data(struct inode *inode)
 291 {
 292         if (EXT4_JOURNAL(inode) == NULL)
 293                 return 0;
 294         if (!S_ISREG(inode->i_mode))
 295                 return 0;
 296         if (EXT4_I(inode)->i_flags & EXT4_JOURNAL_DATA_FL)
 297                 return 0;
 298         if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
 299                 return 1;
 300         return 0;
 301 }
 302
 303 static inline int ext4_should_writeback_data(struct inode *inode)
 304 {
 305         if (!S_ISREG(inode->i_mode))
 306                 return 0;
 307         if (EXT4_JOURNAL(inode) == NULL)
 308                 return 1;
 309         if (EXT4_I(inode)->i_flags & EXT4_JOURNAL_DATA_FL)
 310                 return 0;
 311         if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
 312                 return 1;
 313         return 0;
 314 }
 315
 316 #endif  /* _EXT4_JBD2_H */