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. 124 */ 125 void ext4_journal_abort_handle(const char *caller, const char *err_fn, 126 struct buffer_head *bh, handle_t *handle, int err); 127 128 int __ext4_journal_get_undo_access(const char *where, handle_t *handle, 129 struct buffer_head *bh); 130 131 int __ext4_journal_get_write_access(const char *where, handle_t *handle, 132 struct buffer_head *bh); 133 134 int __ext4_forget(const char *where, handle_t *handle, int is_metadata, 135 struct inode *inode, struct buffer_head *bh, 136 ext4_fsblk_t blocknr); 137 138 int __ext4_journal_get_create_access(const char *where, 139 handle_t *handle, struct buffer_head *bh); 140 141 int __ext4_handle_dirty_metadata(const char *where, handle_t *handle, 142 struct inode *inode, struct buffer_head *bh); 143 144 #define ext4_journal_get_undo_access(handle, bh) \ 145 __ext4_journal_get_undo_access(__func__, (handle), (bh)) 146 #define ext4_journal_get_write_access(handle, bh) \ 147 __ext4_journal_get_write_access(__func__, (handle), (bh)) 148 #define ext4_forget(handle, is_metadata, inode, bh, block_nr) \ 149 __ext4_forget(__func__, (handle), (is_metadata), (inode), (bh),\ 150 (block_nr)) 151 #define ext4_journal_get_create_access(handle, bh) \ 152 __ext4_journal_get_create_access(__func__, (handle), (bh)) 153 #define ext4_handle_dirty_metadata(handle, inode, bh) \ 154 __ext4_handle_dirty_metadata(__func__, (handle), (inode), (bh)) 155 156 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks); 157 int __ext4_journal_stop(const char *where, handle_t *handle); 158 159 #define EXT4_NOJOURNAL_MAX_REF_COUNT ((unsigned long) 4096) 160 161 /* Note: Do not use this for NULL handles. This is only to determine if 162 * a properly allocated handle is using a journal or not. */ 163 static inline int ext4_handle_valid(handle_t *handle) 164 { 165 if ((unsigned long)handle < EXT4_NOJOURNAL_MAX_REF_COUNT) 166 return 0; 167 return 1; 168 } 169 170 static inline void ext4_handle_sync(handle_t *handle) 171 { 172 if (ext4_handle_valid(handle)) 173 handle->h_sync = 1; 174 } 175 176 static inline void ext4_handle_release_buffer(handle_t *handle, 177 struct buffer_head *bh) 178 { 179 if (ext4_handle_valid(handle)) 180 jbd2_journal_release_buffer(handle, bh); 181 } 182 183 static inline int ext4_handle_is_aborted(handle_t *handle) 184 { 185 if (ext4_handle_valid(handle)) 186 return is_handle_aborted(handle); 187 return 0; 188 } 189 190 static inline int ext4_handle_has_enough_credits(handle_t *handle, int needed) 191 { 192 if (ext4_handle_valid(handle) && handle->h_buffer_credits < needed) 193 return 0; 194 return 1; 195 } 196 197 static inline void ext4_journal_release_buffer(handle_t *handle, 198 struct buffer_head *bh) 199 { 200 if (ext4_handle_valid(handle)) 201 jbd2_journal_release_buffer(handle, bh); 202 } 203 204 static inline handle_t *ext4_journal_start(struct inode *inode, int nblocks) 205 { 206 return ext4_journal_start_sb(inode->i_sb, nblocks); 207 } 208 209 #define ext4_journal_stop(handle) \ 210 __ext4_journal_stop(__func__, (handle)) 211 212 static inline handle_t *ext4_journal_current_handle(void) 213 { 214 return journal_current_handle(); 215 } 216 217 static inline int ext4_journal_extend(handle_t *handle, int nblocks) 218 { 219 if (ext4_handle_valid(handle)) 220 return jbd2_journal_extend(handle, nblocks); 221 return 0; 222 } 223 224 static inline int ext4_journal_restart(handle_t *handle, int nblocks) 225 { 226 if (ext4_handle_valid(handle)) 227 return jbd2_journal_restart(handle, nblocks); 228 return 0; 229 } 230 231 static inline int ext4_journal_blocks_per_page(struct inode *inode) 232 { 233 if (EXT4_JOURNAL(inode) != NULL) 234 return jbd2_journal_blocks_per_page(inode); 235 return 0; 236 } 237 238 static inline int ext4_journal_force_commit(journal_t *journal) 239 { 240 if (journal) 241 return jbd2_journal_force_commit(journal); 242 return 0; 243 } 244 245 static inline int ext4_jbd2_file_inode(handle_t *handle, struct inode *inode) 246 { 247 if (ext4_handle_valid(handle)) 248 return jbd2_journal_file_inode(handle, &EXT4_I(inode)->jinode); 249 return 0; 250 } 251 252 static inline void ext4_update_inode_fsync_trans(handle_t *handle, 253 struct inode *inode, 254 int datasync) 255 { 256 struct ext4_inode_info *ei = EXT4_I(inode); 257 258 if (ext4_handle_valid(handle)) { 259 ei->i_sync_tid = handle->h_transaction->t_tid; 260 if (datasync) 261 ei->i_datasync_tid = handle->h_transaction->t_tid; 262 } 263 } 264 265 /* super.c */ 266 int ext4_force_commit(struct super_block *sb); 267 268 static inline int ext4_should_journal_data(struct inode *inode) 269 { 270 if (EXT4_JOURNAL(inode) == NULL) 271 return 0; 272 if (!S_ISREG(inode->i_mode)) 273 return 1; 274 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) 275 return 1; 276 if (EXT4_I(inode)->i_flags & EXT4_JOURNAL_DATA_FL) 277 return 1; 278 return 0; 279 } 280 281 static inline int ext4_should_order_data(struct inode *inode) 282 { 283 if (EXT4_JOURNAL(inode) == NULL) 284 return 0; 285 if (!S_ISREG(inode->i_mode)) 286 return 0; 287 if (EXT4_I(inode)->i_flags & EXT4_JOURNAL_DATA_FL) 288 return 0; 289 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) 290 return 1; 291 return 0; 292 } 293 294 static inline int ext4_should_writeback_data(struct inode *inode) 295 { 296 if (!S_ISREG(inode->i_mode)) 297 return 0; 298 if (EXT4_JOURNAL(inode) == NULL) 299 return 1; 300 if (EXT4_I(inode)->i_flags & EXT4_JOURNAL_DATA_FL) 301 return 0; 302 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA) 303 return 1; 304 return 0; 305 } 306 307 /* 308 * This function controls whether or not we should try to go down the 309 * dioread_nolock code paths, which makes it safe to avoid taking 310 * i_mutex for direct I/O reads. This only works for extent-based 311 * files, and it doesn't work for nobh or if data journaling is 312 * enabled, since the dioread_nolock code uses b_private to pass 313 * information back to the I/O completion handler, and this conflicts 314 * with the jbd's use of b_private. 315 */ 316 static inline int ext4_should_dioread_nolock(struct inode *inode) 317 { 318 if (!test_opt(inode->i_sb, DIOREAD_NOLOCK)) 319 return 0; 320 if (test_opt(inode->i_sb, NOBH)) 321 return 0; 322 if (!S_ISREG(inode->i_mode)) 323 return 0; 324 if (!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)) 325 return 0; 326 if (ext4_should_journal_data(inode)) 327 return 0; 328 return 1; 329 } 330 331 #endif /* _EXT4_JBD2_H */ 332