/* -*- mode: c; c-basic-offset: 8; -*- * vim: noexpandtab sw=8 ts=8 sts=0: * * journal.h * * Defines journalling api and structures. * * Copyright (C) 2003, 2005 Oracle. All rights reserved. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public * License along with this program; if not, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 021110-1307, USA. */ #ifndef OCFS2_JOURNAL_H #define OCFS2_JOURNAL_H #include <linux/fs.h> #include <linux/jbd.h> enum ocfs2_journal_state { OCFS2_JOURNAL_FREE = 0, OCFS2_JOURNAL_LOADED, OCFS2_JOURNAL_IN_SHUTDOWN, }; struct ocfs2_super; struct ocfs2_dinode; struct ocfs2_journal { enum ocfs2_journal_state j_state; /* Journals current state */ journal_t *j_journal; /* The kernels journal type */ struct inode *j_inode; /* Kernel inode pointing to * this journal */ struct ocfs2_super *j_osb; /* pointer to the super * block for the node * we're currently * running on -- not * necessarily the super * block from the node * which we usually run * from (recovery, * etc) */ struct buffer_head *j_bh; /* Journal disk inode block */ atomic_t j_num_trans; /* Number of transactions * currently in the system. */ unsigned long j_trans_id; struct rw_semaphore j_trans_barrier; wait_queue_head_t j_checkpointed; spinlock_t j_lock; struct list_head j_la_cleanups; struct work_struct j_recovery_work; }; extern spinlock_t trans_inc_lock; /* wrap j_trans_id so we never have it equal to zero. */ static inline unsigned long ocfs2_inc_trans_id(struct ocfs2_journal *j) { unsigned long old_id; spin_lock(&trans_inc_lock); old_id = j->j_trans_id++; if (unlikely(!j->j_trans_id)) j->j_trans_id = 1; spin_unlock(&trans_inc_lock); return old_id; } static inline void ocfs2_set_inode_lock_trans(struct ocfs2_journal *journal, struct inode *inode) { spin_lock(&trans_inc_lock); OCFS2_I(inode)->ip_last_trans = journal->j_trans_id; spin_unlock(&trans_inc_lock); } /* Used to figure out whether it's safe to drop a metadata lock on an * inode. Returns true if all the inodes changes have been * checkpointed to disk. You should be holding the spinlock on the * metadata lock while calling this to be sure that nobody can take * the lock and put it on another transaction. */ static inline int ocfs2_inode_fully_checkpointed(struct inode *inode) { int ret; struct ocfs2_journal *journal = OCFS2_SB(inode->i_sb)->journal; spin_lock(&trans_inc_lock); ret = time_after(journal->j_trans_id, OCFS2_I(inode)->ip_last_trans); spin_unlock(&trans_inc_lock); return ret; } /* convenience function to check if an inode is still new (has never * hit disk) Will do you a favor and set created_trans = 0 when you've * been checkpointed. returns '1' if the inode is still new. */ static inline int ocfs2_inode_is_new(struct inode *inode) { int ret; /* System files are never "new" as they're written out by * mkfs. This helps us early during mount, before we have the * journal open and j_trans_id could be junk. */ if (OCFS2_I(inode)->ip_flags & OCFS2_INODE_SYSTEM_FILE) return 0; spin_lock(&trans_inc_lock); ret = !(time_after(OCFS2_SB(inode->i_sb)->journal->j_trans_id, OCFS2_I(inode)->ip_created_trans)); if (!ret) OCFS2_I(inode)->ip_created_trans = 0; spin_unlock(&trans_inc_lock); return ret; } static inline void ocfs2_inode_set_new(struct ocfs2_super *osb, struct inode *inode) { spin_lock(&trans_inc_lock); OCFS2_I(inode)->ip_created_trans = osb->journal->j_trans_id; spin_unlock(&trans_inc_lock); } /* Exported only for the journal struct init code in super.c. Do not call. */ void ocfs2_complete_recovery(struct work_struct *work); /* * Journal Control: * Initialize, Load, Shutdown, Wipe a journal. * * ocfs2_journal_init - Initialize journal structures in the OSB. * ocfs2_journal_load - Load the given journal off disk. Replay it if * there's transactions still in there. * ocfs2_journal_shutdown - Shutdown a journal, this will flush all * uncommitted, uncheckpointed transactions. * ocfs2_journal_wipe - Wipe transactions from a journal. Optionally * zero out each block. * ocfs2_recovery_thread - Perform recovery on a node. osb is our own osb. * ocfs2_mark_dead_nodes - Start recovery on nodes we won't get a heartbeat * event on. * ocfs2_start_checkpoint - Kick the commit thread to do a checkpoint. */ void ocfs2_set_journal_params(struct ocfs2_super *osb); int ocfs2_journal_init(struct ocfs2_journal *journal, int *dirty); void ocfs2_journal_shutdown(struct ocfs2_super *osb); int ocfs2_journal_wipe(struct ocfs2_journal *journal, int full); int ocfs2_journal_load(struct ocfs2_journal *journal, int local); int ocfs2_check_journals_nolocks(struct ocfs2_super *osb); void ocfs2_recovery_thread(struct ocfs2_super *osb, int node_num); int ocfs2_mark_dead_nodes(struct ocfs2_super *osb); void ocfs2_complete_mount_recovery(struct ocfs2_super *osb); static inline void ocfs2_start_checkpoint(struct ocfs2_super *osb) { atomic_set(&osb->needs_checkpoint, 1); wake_up(&osb->checkpoint_event); } static inline void ocfs2_checkpoint_inode(struct inode *inode) { struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); if (ocfs2_mount_local(osb)) return; if (!ocfs2_inode_fully_checkpointed(inode)) { /* WARNING: This only kicks off a single * checkpoint. If someone races you and adds more * metadata to the journal, you won't know, and will * wind up waiting *alot* longer than necessary. Right * now we only use this in clear_inode so that's * OK. */ ocfs2_start_checkpoint(osb); wait_event(osb->journal->j_checkpointed, ocfs2_inode_fully_checkpointed(inode)); } } /* * Transaction Handling: * Manage the lifetime of a transaction handle. * * ocfs2_start_trans - Begin a transaction. Give it an upper estimate of * the number of blocks that will be changed during * this handle. * ocfs2_commit_trans - Complete a handle. It might return -EIO if * the journal was aborted. The majority of paths don't * check the return value as an error there comes too * late to do anything (and will be picked up in a * later transaction). * ocfs2_extend_trans - Extend a handle by nblocks credits. This may * commit the handle to disk in the process, but will * not release any locks taken during the transaction. * ocfs2_journal_access - Notify the handle that we want to journal this * buffer. Will have to call ocfs2_journal_dirty once * we've actually dirtied it. Type is one of . or . * ocfs2_journal_dirty - Mark a journalled buffer as having dirty data. * ocfs2_journal_dirty_data - Indicate that a data buffer should go out before * the current handle commits. */ /* You must always start_trans with a number of buffs > 0, but it's * perfectly legal to go through an entire transaction without having * dirtied any buffers. */ handle_t *ocfs2_start_trans(struct ocfs2_super *osb, int max_buffs); int ocfs2_commit_trans(struct ocfs2_super *osb, handle_t *handle); int ocfs2_extend_trans(handle_t *handle, int nblocks); /* * Create access is for when we get a newly created buffer and we're * not gonna read it off disk, but rather fill it ourselves. Right * now, we don't do anything special with this (it turns into a write * request), but this is a good placeholder in case we do... * * Write access is for when we read a block off disk and are going to * modify it. This way the journalling layer knows it may need to make * a copy of that block (if it's part of another, uncommitted * transaction) before we do so. */ #define OCFS2_JOURNAL_ACCESS_CREATE 0 #define OCFS2_JOURNAL_ACCESS_WRITE 1 #define OCFS2_JOURNAL_ACCESS_UNDO 2 int ocfs2_journal_access(handle_t *handle, struct inode *inode, struct buffer_head *bh, int type); /* * A word about the journal_access/journal_dirty "dance". It is * entirely legal to journal_access a buffer more than once (as long * as the access type is the same -- I'm not sure what will happen if * access type is different but this should never happen anyway) It is * also legal to journal_dirty a buffer more than once. In fact, you * can even journal_access a buffer after you've done a * journal_access/journal_dirty pair. The only thing you cannot do * however, is journal_dirty a buffer which you haven't yet passed to * journal_access at least once. * * That said, 99% of the time this doesn't matter and this is what the * path looks like: * * <read a bh> * ocfs2_journal_access(handle, bh, OCFS2_JOURNAL_ACCESS_WRITE); * <modify the bh> * ocfs2_journal_dirty(handle, bh); */ int ocfs2_journal_dirty(handle_t *handle, struct buffer_head *bh); int ocfs2_journal_dirty_data(handle_t *handle, struct buffer_head *bh); /* * Credit Macros: * Convenience macros to calculate number of credits needed. * * For convenience sake, I have a set of macros here which calculate * the *maximum* number of sectors which will be changed for various * metadata updates. */ /* simple file updates like chmod, etc. */ #define OCFS2_INODE_UPDATE_CREDITS 1 /* get one bit out of a suballocator: dinode + group descriptor + * prev. group desc. if we relink. */ #define OCFS2_SUBALLOC_ALLOC (3) /* dinode + group descriptor update. We don't relink on free yet. */ #define OCFS2_SUBALLOC_FREE (2) #define OCFS2_TRUNCATE_LOG_UPDATE OCFS2_INODE_UPDATE_CREDITS #define OCFS2_TRUNCATE_LOG_FLUSH_ONE_REC (OCFS2_SUBALLOC_FREE \ + OCFS2_TRUNCATE_LOG_UPDATE) #define OCFS2_REMOVE_EXTENT_CREDITS (OCFS2_TRUNCATE_LOG_UPDATE + OCFS2_INODE_UPDATE_CREDITS) /* data block for new dir/symlink, 2 for bitmap updates (bitmap fe + * bitmap block for the new bit) */ #define OCFS2_DIR_LINK_ADDITIONAL_CREDITS (1 + 2) /* parent fe, parent block, new file entry, inode alloc fe, inode alloc * group descriptor + mkdir/symlink blocks */ #define OCFS2_MKNOD_CREDITS (3 + OCFS2_SUBALLOC_ALLOC \ + OCFS2_DIR_LINK_ADDITIONAL_CREDITS) /* local alloc metadata change + main bitmap updates */ #define OCFS2_WINDOW_MOVE_CREDITS (OCFS2_INODE_UPDATE_CREDITS \ + OCFS2_SUBALLOC_ALLOC + OCFS2_SUBALLOC_FREE) /* used when we don't need an allocation change for a dir extend. One * for the dinode, one for the new block. */ #define OCFS2_SIMPLE_DIR_EXTEND_CREDITS (2) /* file update (nlink, etc) + directory mtime/ctime + dir entry block */ #define OCFS2_LINK_CREDITS (2*OCFS2_INODE_UPDATE_CREDITS + 1) /* inode + dir inode (if we unlink a dir), + dir entry block + orphan * dir inode link */ #define OCFS2_UNLINK_CREDITS (2 * OCFS2_INODE_UPDATE_CREDITS + 1 \ + OCFS2_LINK_CREDITS) /* dinode + orphan dir dinode + inode alloc dinode + orphan dir entry + * inode alloc group descriptor */ #define OCFS2_DELETE_INODE_CREDITS (3 * OCFS2_INODE_UPDATE_CREDITS + 1 + 1) /* dinode update, old dir dinode update, new dir dinode update, old * dir dir entry, new dir dir entry, dir entry update for renaming * directory + target unlink */ #define OCFS2_RENAME_CREDITS (3 * OCFS2_INODE_UPDATE_CREDITS + 3 \ + OCFS2_UNLINK_CREDITS) static inline int ocfs2_calc_extend_credits(struct super_block *sb, struct ocfs2_dinode *fe, u32 bits_wanted) { int bitmap_blocks, sysfile_bitmap_blocks, dinode_blocks; /* bitmap dinode, group desc. + relinked group. */ bitmap_blocks = OCFS2_SUBALLOC_ALLOC; /* we might need to shift tree depth so lets assume an * absolute worst case of complete fragmentation. Even with * that, we only need one update for the dinode, and then * however many metadata chunks needed * a remaining suballoc * alloc. */ sysfile_bitmap_blocks = 1 + (OCFS2_SUBALLOC_ALLOC - 1) * ocfs2_extend_meta_needed(fe); /* this does not include *new* metadata blocks, which are * accounted for in sysfile_bitmap_blocks. fe + * prev. last_eb_blk + blocks along edge of tree. * calc_symlink_credits passes because we just need 1 * credit for the dinode there. */ dinode_blocks = 1 + 1 + le16_to_cpu(fe->id2.i_list.l_tree_depth); return bitmap_blocks + sysfile_bitmap_blocks + dinode_blocks; } static inline int ocfs2_calc_symlink_credits(struct super_block *sb) { int blocks = OCFS2_MKNOD_CREDITS; /* links can be longer than one block so we may update many * within our single allocated extent. */ blocks += ocfs2_clusters_to_blocks(sb, 1); return blocks; } static inline int ocfs2_calc_group_alloc_credits(struct super_block *sb, unsigned int cpg) { int blocks; int bitmap_blocks = OCFS2_SUBALLOC_ALLOC + 1; /* parent inode update + new block group header + bitmap inode update + bitmap blocks affected */ blocks = 1 + 1 + 1 + bitmap_blocks; return blocks; } static inline int ocfs2_calc_tree_trunc_credits(struct super_block *sb, unsigned int clusters_to_del, struct ocfs2_dinode *fe, struct ocfs2_extent_list *last_el) { /* for dinode + all headers in this pass + update to next leaf */ u16 next_free = le16_to_cpu(last_el->l_next_free_rec); u16 tree_depth = le16_to_cpu(fe->id2.i_list.l_tree_depth); int credits = 1 + tree_depth + 1; int i; i = next_free - 1; BUG_ON(i < 0); /* We may be deleting metadata blocks, so metadata alloc dinode + one desc. block for each possible delete. */ if (tree_depth && next_free == 1 && ocfs2_rec_clusters(last_el, &last_el->l_recs[i]) == clusters_to_del) credits += 1 + tree_depth; /* update to the truncate log. */ credits += OCFS2_TRUNCATE_LOG_UPDATE; return credits; } #endif /* OCFS2_JOURNAL_H */