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 2*EXT4_QUOTA_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 2*EXT4_QUOTA_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 #define EXT4_QUOTA_DEL_BLOCKS(sb) (test_opt(sb, QUOTA) ? (DQUOT_DEL_ALLOC*\ 96 (EXT4_SINGLEDATA_TRANS_BLOCKS(sb)-3)+3+DQUOT_DEL_REWRITE) : 0) 97 #else 98 #define EXT4_QUOTA_TRANS_BLOCKS(sb) 0 99 #define EXT4_QUOTA_INIT_BLOCKS(sb) 0 100 #define EXT4_QUOTA_DEL_BLOCKS(sb) 0 101 #endif 102 103 int 104 ext4_mark_iloc_dirty(handle_t *handle, 105 struct inode *inode, 106 struct ext4_iloc *iloc); 107 108 /* 109 * On success, We end up with an outstanding reference count against 110 * iloc->bh. This _must_ be cleaned up later. 111 */ 112 113 int ext4_reserve_inode_write(handle_t *handle, struct inode *inode, 114 struct ext4_iloc *iloc); 115 116 int ext4_mark_inode_dirty(handle_t *handle, struct inode *inode); 117 118 /* 119 * Wrapper functions with which ext4 calls into JBD. The intent here is 120 * to allow these to be turned into appropriate stubs so ext4 can control 121 * ext2 filesystems, so ext2+ext4 systems only nee one fs. This work hasn't 122 * been done yet. 123 */ 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 /* When called with an invalid handle, this will still do a put on the BH */ 135 int __ext4_journal_forget(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_revoke(const char *where, handle_t *handle, 140 ext4_fsblk_t blocknr, struct buffer_head *bh); 141 142 int __ext4_journal_get_create_access(const char *where, 143 handle_t *handle, struct buffer_head *bh); 144 145 int __ext4_handle_dirty_metadata(const char *where, handle_t *handle, 146 struct inode *inode, struct buffer_head *bh); 147 148 #define ext4_journal_get_undo_access(handle, bh) \ 149 __ext4_journal_get_undo_access(__func__, (handle), (bh)) 150 #define ext4_journal_get_write_access(handle, bh) \ 151 __ext4_journal_get_write_access(__func__, (handle), (bh)) 152 #define ext4_journal_revoke(handle, blocknr, bh) \ 153 __ext4_journal_revoke(__func__, (handle), (blocknr), (bh)) 154 #define ext4_journal_get_create_access(handle, bh) \ 155 __ext4_journal_get_create_access(__func__, (handle), (bh)) 156 #define ext4_journal_forget(handle, bh) \ 157 __ext4_journal_forget(__func__, (handle), (bh)) 158 #define ext4_handle_dirty_metadata(handle, inode, bh) \ 159 __ext4_handle_dirty_metadata(__func__, (handle), (inode), (bh)) 160 161 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks); 162 int __ext4_journal_stop(const char *where, handle_t *handle); 163 164 #define EXT4_NOJOURNAL_MAX_REF_COUNT ((unsigned long) 4096) 165 166 /* Note: Do not use this for NULL handles. This is only to determine if 167 * a properly allocated handle is using a journal or not. */ 168 static inline int ext4_handle_valid(handle_t *handle) 169 { 170 if ((unsigned long)handle < EXT4_NOJOURNAL_MAX_REF_COUNT) 171 return 0; 172 return 1; 173 } 174 175 static inline void ext4_handle_sync(handle_t *handle) 176 { 177 if (ext4_handle_valid(handle)) 178 handle->h_sync = 1; 179 } 180 181 static inline void ext4_handle_release_buffer(handle_t *handle, 182 struct buffer_head *bh) 183 { 184 if (ext4_handle_valid(handle)) 185 jbd2_journal_release_buffer(handle, bh); 186 } 187 188 static inline int ext4_handle_is_aborted(handle_t *handle) 189 { 190 if (ext4_handle_valid(handle)) 191 return is_handle_aborted(handle); 192 return 0; 193 } 194 195 static inline int ext4_handle_has_enough_credits(handle_t *handle, int needed) 196 { 197 if (ext4_handle_valid(handle) && handle->h_buffer_credits < needed) 198 return 0; 199 return 1; 200 } 201 202 static inline void ext4_journal_release_buffer(handle_t *handle, 203 struct buffer_head *bh) 204 { 205 if (ext4_handle_valid(handle)) 206 jbd2_journal_release_buffer(handle, bh); 207 } 208 209 static inline handle_t *ext4_journal_start(struct inode *inode, int nblocks) 210 { 211 return ext4_journal_start_sb(inode->i_sb, nblocks); 212 } 213 214 #define ext4_journal_stop(handle) \ 215 __ext4_journal_stop(__func__, (handle)) 216 217 static inline handle_t *ext4_journal_current_handle(void) 218 { 219 return journal_current_handle(); 220 } 221 222 static inline int ext4_journal_extend(handle_t *handle, int nblocks) 223 { 224 if (ext4_handle_valid(handle)) 225 return jbd2_journal_extend(handle, nblocks); 226 return 0; 227 } 228 229 static inline int ext4_journal_restart(handle_t *handle, int nblocks) 230 { 231 if (ext4_handle_valid(handle)) 232 return jbd2_journal_restart(handle, nblocks); 233 return 0; 234 } 235 236 static inline int ext4_journal_blocks_per_page(struct inode *inode) 237 { 238 if (EXT4_JOURNAL(inode) != NULL) 239 return jbd2_journal_blocks_per_page(inode); 240 return 0; 241 } 242 243 static inline int ext4_journal_force_commit(journal_t *journal) 244 { 245 if (journal) 246 return jbd2_journal_force_commit(journal); 247 return 0; 248 } 249 250 static inline int ext4_jbd2_file_inode(handle_t *handle, struct inode *inode) 251 { 252 if (ext4_handle_valid(handle)) 253 return jbd2_journal_file_inode(handle, &EXT4_I(inode)->jinode); 254 return 0; 255 } 256 257 /* super.c */ 258 int ext4_force_commit(struct super_block *sb); 259 260 static inline int ext4_should_journal_data(struct inode *inode) 261 { 262 if (EXT4_JOURNAL(inode) == NULL) 263 return 0; 264 if (!S_ISREG(inode->i_mode)) 265 return 1; 266 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) 267 return 1; 268 if (EXT4_I(inode)->i_flags & EXT4_JOURNAL_DATA_FL) 269 return 1; 270 return 0; 271 } 272 273 static inline int ext4_should_order_data(struct inode *inode) 274 { 275 if (EXT4_JOURNAL(inode) == NULL) 276 return 0; 277 if (!S_ISREG(inode->i_mode)) 278 return 0; 279 if (EXT4_I(inode)->i_flags & EXT4_JOURNAL_DATA_FL) 280 return 0; 281 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) 282 return 1; 283 return 0; 284 } 285 286 static inline int ext4_should_writeback_data(struct inode *inode) 287 { 288 if (!S_ISREG(inode->i_mode)) 289 return 0; 290 if (EXT4_JOURNAL(inode) == NULL) 291 return 1; 292 if (EXT4_I(inode)->i_flags & EXT4_JOURNAL_DATA_FL) 293 return 0; 294 if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA) 295 return 1; 296 return 0; 297 } 298 299 #endif /* _EXT4_JBD2_H */ 300