1 /* -*- mode: c; c-basic-offset: 8; -*- 2 * vim: noexpandtab sw=8 ts=8 sts=0: 3 * 4 * journal.h 5 * 6 * Defines journalling api and structures. 7 * 8 * Copyright (C) 2003, 2005 Oracle. All rights reserved. 9 * 10 * This program is free software; you can redistribute it and/or 11 * modify it under the terms of the GNU General Public 12 * License as published by the Free Software Foundation; either 13 * version 2 of the License, or (at your option) any later version. 14 * 15 * This program is distributed in the hope that it will be useful, 16 * but WITHOUT ANY WARRANTY; without even the implied warranty of 17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 18 * General Public License for more details. 19 * 20 * You should have received a copy of the GNU General Public 21 * License along with this program; if not, write to the 22 * Free Software Foundation, Inc., 59 Temple Place - Suite 330, 23 * Boston, MA 021110-1307, USA. 24 */ 25 26 #ifndef OCFS2_JOURNAL_H 27 #define OCFS2_JOURNAL_H 28 29 #include <linux/fs.h> 30 #include <linux/jbd.h> 31 32 enum ocfs2_journal_state { 33 OCFS2_JOURNAL_FREE = 0, 34 OCFS2_JOURNAL_LOADED, 35 OCFS2_JOURNAL_IN_SHUTDOWN, 36 }; 37 38 struct ocfs2_super; 39 struct ocfs2_dinode; 40 struct ocfs2_journal_handle; 41 42 struct ocfs2_journal { 43 enum ocfs2_journal_state j_state; /* Journals current state */ 44 45 journal_t *j_journal; /* The kernels journal type */ 46 struct inode *j_inode; /* Kernel inode pointing to 47 * this journal */ 48 struct ocfs2_super *j_osb; /* pointer to the super 49 * block for the node 50 * we're currently 51 * running on -- not 52 * necessarily the super 53 * block from the node 54 * which we usually run 55 * from (recovery, 56 * etc) */ 57 struct buffer_head *j_bh; /* Journal disk inode block */ 58 atomic_t j_num_trans; /* Number of transactions 59 * currently in the system. */ 60 unsigned long j_trans_id; 61 struct rw_semaphore j_trans_barrier; 62 wait_queue_head_t j_checkpointed; 63 64 spinlock_t j_lock; 65 struct list_head j_la_cleanups; 66 struct work_struct j_recovery_work; 67 }; 68 69 extern spinlock_t trans_inc_lock; 70 71 /* wrap j_trans_id so we never have it equal to zero. */ 72 static inline unsigned long ocfs2_inc_trans_id(struct ocfs2_journal *j) 73 { 74 unsigned long old_id; 75 spin_lock(&trans_inc_lock); 76 old_id = j->j_trans_id++; 77 if (unlikely(!j->j_trans_id)) 78 j->j_trans_id = 1; 79 spin_unlock(&trans_inc_lock); 80 return old_id; 81 } 82 83 static inline void ocfs2_set_inode_lock_trans(struct ocfs2_journal *journal, 84 struct inode *inode) 85 { 86 spin_lock(&trans_inc_lock); 87 OCFS2_I(inode)->ip_last_trans = journal->j_trans_id; 88 spin_unlock(&trans_inc_lock); 89 } 90 91 /* Used to figure out whether it's safe to drop a metadata lock on an 92 * inode. Returns true if all the inodes changes have been 93 * checkpointed to disk. You should be holding the spinlock on the 94 * metadata lock while calling this to be sure that nobody can take 95 * the lock and put it on another transaction. */ 96 static inline int ocfs2_inode_fully_checkpointed(struct inode *inode) 97 { 98 int ret; 99 struct ocfs2_journal *journal = OCFS2_SB(inode->i_sb)->journal; 100 101 spin_lock(&trans_inc_lock); 102 ret = time_after(journal->j_trans_id, OCFS2_I(inode)->ip_last_trans); 103 spin_unlock(&trans_inc_lock); 104 return ret; 105 } 106 107 /* convenience function to check if an inode is still new (has never 108 * hit disk) Will do you a favor and set created_trans = 0 when you've 109 * been checkpointed. returns '1' if the inode is still new. */ 110 static inline int ocfs2_inode_is_new(struct inode *inode) 111 { 112 int ret; 113 114 /* System files are never "new" as they're written out by 115 * mkfs. This helps us early during mount, before we have the 116 * journal open and j_trans_id could be junk. */ 117 if (OCFS2_I(inode)->ip_flags & OCFS2_INODE_SYSTEM_FILE) 118 return 0; 119 spin_lock(&trans_inc_lock); 120 ret = !(time_after(OCFS2_SB(inode->i_sb)->journal->j_trans_id, 121 OCFS2_I(inode)->ip_created_trans)); 122 if (!ret) 123 OCFS2_I(inode)->ip_created_trans = 0; 124 spin_unlock(&trans_inc_lock); 125 return ret; 126 } 127 128 static inline void ocfs2_inode_set_new(struct ocfs2_super *osb, 129 struct inode *inode) 130 { 131 spin_lock(&trans_inc_lock); 132 OCFS2_I(inode)->ip_created_trans = osb->journal->j_trans_id; 133 spin_unlock(&trans_inc_lock); 134 } 135 136 extern kmem_cache_t *ocfs2_lock_cache; 137 138 struct ocfs2_journal_lock { 139 struct inode *jl_inode; 140 struct list_head jl_lock_list; 141 }; 142 143 struct ocfs2_journal_handle { 144 handle_t *k_handle; /* kernel handle. */ 145 struct ocfs2_journal *journal; 146 u32 flags; /* see flags below. */ 147 int max_buffs; /* Buffs reserved by this handle */ 148 149 /* The following two fields are for ocfs2_handle_add_lock */ 150 int num_locks; 151 struct list_head locks; /* A bunch of locks to 152 * release on commit. This 153 * should be a list_head */ 154 155 struct list_head inode_list; 156 }; 157 158 #define OCFS2_HANDLE_STARTED 1 159 /* should we sync-commit this handle? */ 160 #define OCFS2_HANDLE_SYNC 2 161 static inline int ocfs2_handle_started(struct ocfs2_journal_handle *handle) 162 { 163 return handle->flags & OCFS2_HANDLE_STARTED; 164 } 165 166 static inline void ocfs2_handle_set_sync(struct ocfs2_journal_handle *handle, int sync) 167 { 168 if (sync) 169 handle->flags |= OCFS2_HANDLE_SYNC; 170 else 171 handle->flags &= ~OCFS2_HANDLE_SYNC; 172 } 173 174 /* Exported only for the journal struct init code in super.c. Do not call. */ 175 void ocfs2_complete_recovery(void *data); 176 177 /* 178 * Journal Control: 179 * Initialize, Load, Shutdown, Wipe a journal. 180 * 181 * ocfs2_journal_init - Initialize journal structures in the OSB. 182 * ocfs2_journal_load - Load the given journal off disk. Replay it if 183 * there's transactions still in there. 184 * ocfs2_journal_shutdown - Shutdown a journal, this will flush all 185 * uncommitted, uncheckpointed transactions. 186 * ocfs2_journal_wipe - Wipe transactions from a journal. Optionally 187 * zero out each block. 188 * ocfs2_recovery_thread - Perform recovery on a node. osb is our own osb. 189 * ocfs2_mark_dead_nodes - Start recovery on nodes we won't get a heartbeat 190 * event on. 191 * ocfs2_start_checkpoint - Kick the commit thread to do a checkpoint. 192 */ 193 void ocfs2_set_journal_params(struct ocfs2_super *osb); 194 int ocfs2_journal_init(struct ocfs2_journal *journal, 195 int *dirty); 196 void ocfs2_journal_shutdown(struct ocfs2_super *osb); 197 int ocfs2_journal_wipe(struct ocfs2_journal *journal, 198 int full); 199 int ocfs2_journal_load(struct ocfs2_journal *journal); 200 int ocfs2_check_journals_nolocks(struct ocfs2_super *osb); 201 void ocfs2_recovery_thread(struct ocfs2_super *osb, 202 int node_num); 203 int ocfs2_mark_dead_nodes(struct ocfs2_super *osb); 204 void ocfs2_complete_mount_recovery(struct ocfs2_super *osb); 205 206 static inline void ocfs2_start_checkpoint(struct ocfs2_super *osb) 207 { 208 atomic_set(&osb->needs_checkpoint, 1); 209 wake_up(&osb->checkpoint_event); 210 } 211 212 static inline void ocfs2_checkpoint_inode(struct inode *inode) 213 { 214 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); 215 216 if (!ocfs2_inode_fully_checkpointed(inode)) { 217 /* WARNING: This only kicks off a single 218 * checkpoint. If someone races you and adds more 219 * metadata to the journal, you won't know, and will 220 * wind up waiting *alot* longer than necessary. Right 221 * now we only use this in clear_inode so that's 222 * OK. */ 223 ocfs2_start_checkpoint(osb); 224 225 wait_event(osb->journal->j_checkpointed, 226 ocfs2_inode_fully_checkpointed(inode)); 227 } 228 } 229 230 /* 231 * Transaction Handling: 232 * Manage the lifetime of a transaction handle. 233 * 234 * ocfs2_alloc_handle - Only allocate a handle so we can start putting 235 * cluster locks on it. To actually change blocks, 236 * call ocfs2_start_trans with the handle returned 237 * from this function. You may call ocfs2_commit_trans 238 * at any time in the lifetime of a handle. 239 * ocfs2_start_trans - Begin a transaction. Give it an upper estimate of 240 * the number of blocks that will be changed during 241 * this handle. 242 * ocfs2_commit_trans - Complete a handle. 243 * ocfs2_extend_trans - Extend a handle by nblocks credits. This may 244 * commit the handle to disk in the process, but will 245 * not release any locks taken during the transaction. 246 * ocfs2_journal_access - Notify the handle that we want to journal this 247 * buffer. Will have to call ocfs2_journal_dirty once 248 * we've actually dirtied it. Type is one of . or . 249 * ocfs2_journal_dirty - Mark a journalled buffer as having dirty data. 250 * ocfs2_journal_dirty_data - Indicate that a data buffer should go out before 251 * the current handle commits. 252 * ocfs2_handle_add_lock - Sometimes we need to delay lock release 253 * until after a transaction has been completed. Use 254 * ocfs2_handle_add_lock to indicate that a lock needs 255 * to be released at the end of that handle. Locks 256 * will be released in the order that they are added. 257 * ocfs2_handle_add_inode - Add a locked inode to a transaction. 258 */ 259 260 /* You must always start_trans with a number of buffs > 0, but it's 261 * perfectly legal to go through an entire transaction without having 262 * dirtied any buffers. */ 263 struct ocfs2_journal_handle *ocfs2_alloc_handle(struct ocfs2_super *osb); 264 struct ocfs2_journal_handle *ocfs2_start_trans(struct ocfs2_super *osb, 265 struct ocfs2_journal_handle *handle, 266 int max_buffs); 267 void ocfs2_commit_trans(struct ocfs2_journal_handle *handle); 268 int ocfs2_extend_trans(struct ocfs2_journal_handle *handle, 269 int nblocks); 270 271 /* 272 * Create access is for when we get a newly created buffer and we're 273 * not gonna read it off disk, but rather fill it ourselves. Right 274 * now, we don't do anything special with this (it turns into a write 275 * request), but this is a good placeholder in case we do... 276 * 277 * Write access is for when we read a block off disk and are going to 278 * modify it. This way the journalling layer knows it may need to make 279 * a copy of that block (if it's part of another, uncommitted 280 * transaction) before we do so. 281 */ 282 #define OCFS2_JOURNAL_ACCESS_CREATE 0 283 #define OCFS2_JOURNAL_ACCESS_WRITE 1 284 #define OCFS2_JOURNAL_ACCESS_UNDO 2 285 286 int ocfs2_journal_access(struct ocfs2_journal_handle *handle, 287 struct inode *inode, 288 struct buffer_head *bh, 289 int type); 290 /* 291 * A word about the journal_access/journal_dirty "dance". It is 292 * entirely legal to journal_access a buffer more than once (as long 293 * as the access type is the same -- I'm not sure what will happen if 294 * access type is different but this should never happen anyway) It is 295 * also legal to journal_dirty a buffer more than once. In fact, you 296 * can even journal_access a buffer after you've done a 297 * journal_access/journal_dirty pair. The only thing you cannot do 298 * however, is journal_dirty a buffer which you haven't yet passed to 299 * journal_access at least once. 300 * 301 * That said, 99% of the time this doesn't matter and this is what the 302 * path looks like: 303 * 304 * <read a bh> 305 * ocfs2_journal_access(handle, bh, OCFS2_JOURNAL_ACCESS_WRITE); 306 * <modify the bh> 307 * ocfs2_journal_dirty(handle, bh); 308 */ 309 int ocfs2_journal_dirty(struct ocfs2_journal_handle *handle, 310 struct buffer_head *bh); 311 int ocfs2_journal_dirty_data(handle_t *handle, 312 struct buffer_head *bh); 313 int ocfs2_handle_add_lock(struct ocfs2_journal_handle *handle, 314 struct inode *inode); 315 /* 316 * Use this to protect from other processes reading buffer state while 317 * it's in flight. 318 */ 319 void ocfs2_handle_add_inode(struct ocfs2_journal_handle *handle, 320 struct inode *inode); 321 322 /* 323 * Credit Macros: 324 * Convenience macros to calculate number of credits needed. 325 * 326 * For convenience sake, I have a set of macros here which calculate 327 * the *maximum* number of sectors which will be changed for various 328 * metadata updates. 329 */ 330 331 /* simple file updates like chmod, etc. */ 332 #define OCFS2_INODE_UPDATE_CREDITS 1 333 334 /* get one bit out of a suballocator: dinode + group descriptor + 335 * prev. group desc. if we relink. */ 336 #define OCFS2_SUBALLOC_ALLOC (3) 337 338 /* dinode + group descriptor update. We don't relink on free yet. */ 339 #define OCFS2_SUBALLOC_FREE (2) 340 341 #define OCFS2_TRUNCATE_LOG_UPDATE OCFS2_INODE_UPDATE_CREDITS 342 #define OCFS2_TRUNCATE_LOG_FLUSH_ONE_REC (OCFS2_SUBALLOC_FREE \ 343 + OCFS2_TRUNCATE_LOG_UPDATE) 344 345 /* data block for new dir/symlink, 2 for bitmap updates (bitmap fe + 346 * bitmap block for the new bit) */ 347 #define OCFS2_DIR_LINK_ADDITIONAL_CREDITS (1 + 2) 348 349 /* parent fe, parent block, new file entry, inode alloc fe, inode alloc 350 * group descriptor + mkdir/symlink blocks */ 351 #define OCFS2_MKNOD_CREDITS (3 + OCFS2_SUBALLOC_ALLOC \ 352 + OCFS2_DIR_LINK_ADDITIONAL_CREDITS) 353 354 /* local alloc metadata change + main bitmap updates */ 355 #define OCFS2_WINDOW_MOVE_CREDITS (OCFS2_INODE_UPDATE_CREDITS \ 356 + OCFS2_SUBALLOC_ALLOC + OCFS2_SUBALLOC_FREE) 357 358 /* used when we don't need an allocation change for a dir extend. One 359 * for the dinode, one for the new block. */ 360 #define OCFS2_SIMPLE_DIR_EXTEND_CREDITS (2) 361 362 /* file update (nlink, etc) + dir entry block */ 363 #define OCFS2_LINK_CREDITS (OCFS2_INODE_UPDATE_CREDITS + 1) 364 365 /* inode + dir inode (if we unlink a dir), + dir entry block + orphan 366 * dir inode link */ 367 #define OCFS2_UNLINK_CREDITS (2 * OCFS2_INODE_UPDATE_CREDITS + 1 \ 368 + OCFS2_LINK_CREDITS) 369 370 /* dinode + orphan dir dinode + inode alloc dinode + orphan dir entry + 371 * inode alloc group descriptor */ 372 #define OCFS2_DELETE_INODE_CREDITS (3 * OCFS2_INODE_UPDATE_CREDITS + 1 + 1) 373 374 /* dinode update, old dir dinode update, new dir dinode update, old 375 * dir dir entry, new dir dir entry, dir entry update for renaming 376 * directory + target unlink */ 377 #define OCFS2_RENAME_CREDITS (3 * OCFS2_INODE_UPDATE_CREDITS + 3 \ 378 + OCFS2_UNLINK_CREDITS) 379 380 static inline int ocfs2_calc_extend_credits(struct super_block *sb, 381 struct ocfs2_dinode *fe, 382 u32 bits_wanted) 383 { 384 int bitmap_blocks, sysfile_bitmap_blocks, dinode_blocks; 385 386 /* bitmap dinode, group desc. + relinked group. */ 387 bitmap_blocks = OCFS2_SUBALLOC_ALLOC; 388 389 /* we might need to shift tree depth so lets assume an 390 * absolute worst case of complete fragmentation. Even with 391 * that, we only need one update for the dinode, and then 392 * however many metadata chunks needed * a remaining suballoc 393 * alloc. */ 394 sysfile_bitmap_blocks = 1 + 395 (OCFS2_SUBALLOC_ALLOC - 1) * ocfs2_extend_meta_needed(fe); 396 397 /* this does not include *new* metadata blocks, which are 398 * accounted for in sysfile_bitmap_blocks. fe + 399 * prev. last_eb_blk + blocks along edge of tree. 400 * calc_symlink_credits passes because we just need 1 401 * credit for the dinode there. */ 402 dinode_blocks = 1 + 1 + le16_to_cpu(fe->id2.i_list.l_tree_depth); 403 404 return bitmap_blocks + sysfile_bitmap_blocks + dinode_blocks; 405 } 406 407 static inline int ocfs2_calc_symlink_credits(struct super_block *sb) 408 { 409 int blocks = OCFS2_MKNOD_CREDITS; 410 411 /* links can be longer than one block so we may update many 412 * within our single allocated extent. */ 413 blocks += ocfs2_clusters_to_blocks(sb, 1); 414 415 return blocks; 416 } 417 418 static inline int ocfs2_calc_group_alloc_credits(struct super_block *sb, 419 unsigned int cpg) 420 { 421 int blocks; 422 int bitmap_blocks = OCFS2_SUBALLOC_ALLOC + 1; 423 /* parent inode update + new block group header + bitmap inode update 424 + bitmap blocks affected */ 425 blocks = 1 + 1 + 1 + bitmap_blocks; 426 return blocks; 427 } 428 429 static inline int ocfs2_calc_tree_trunc_credits(struct super_block *sb, 430 unsigned int clusters_to_del, 431 struct ocfs2_dinode *fe, 432 struct ocfs2_extent_list *last_el) 433 { 434 /* for dinode + all headers in this pass + update to next leaf */ 435 u16 next_free = le16_to_cpu(last_el->l_next_free_rec); 436 u16 tree_depth = le16_to_cpu(fe->id2.i_list.l_tree_depth); 437 int credits = 1 + tree_depth + 1; 438 int i; 439 440 i = next_free - 1; 441 BUG_ON(i < 0); 442 443 /* We may be deleting metadata blocks, so metadata alloc dinode + 444 one desc. block for each possible delete. */ 445 if (tree_depth && next_free == 1 && 446 le32_to_cpu(last_el->l_recs[i].e_clusters) == clusters_to_del) 447 credits += 1 + tree_depth; 448 449 /* update to the truncate log. */ 450 credits += OCFS2_TRUNCATE_LOG_UPDATE; 451 452 return credits; 453 } 454 455 #endif /* OCFS2_JOURNAL_H */ 456