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Diffstat (limited to 'fs/ocfs2/journal.h')
-rw-r--r-- | fs/ocfs2/journal.h | 457 |
1 files changed, 457 insertions, 0 deletions
diff --git a/fs/ocfs2/journal.h b/fs/ocfs2/journal.h new file mode 100644 index 0000000..7d0a816 --- /dev/null +++ b/fs/ocfs2/journal.h @@ -0,0 +1,457 @@ +/* -*- 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> + +#define OCFS2_CHECKPOINT_INTERVAL (8 * HZ) + +enum ocfs2_journal_state { + OCFS2_JOURNAL_FREE = 0, + OCFS2_JOURNAL_LOADED, + OCFS2_JOURNAL_IN_SHUTDOWN, +}; + +struct ocfs2_super; +struct ocfs2_dinode; +struct ocfs2_journal_handle; + +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); +} + +extern kmem_cache_t *ocfs2_lock_cache; + +struct ocfs2_journal_lock { + struct inode *jl_inode; + struct list_head jl_lock_list; +}; + +struct ocfs2_journal_handle { + handle_t *k_handle; /* kernel handle. */ + struct ocfs2_journal *journal; + u32 flags; /* see flags below. */ + int max_buffs; /* Buffs reserved by this handle */ + + /* The following two fields are for ocfs2_handle_add_lock */ + int num_locks; + struct list_head locks; /* A bunch of locks to + * release on commit. This + * should be a list_head */ + + struct list_head inode_list; +}; + +#define OCFS2_HANDLE_STARTED 1 +/* should we sync-commit this handle? */ +#define OCFS2_HANDLE_SYNC 2 +static inline int ocfs2_handle_started(struct ocfs2_journal_handle *handle) +{ + return handle->flags & OCFS2_HANDLE_STARTED; +} + +static inline void ocfs2_handle_set_sync(struct ocfs2_journal_handle *handle, int sync) +{ + if (sync) + handle->flags |= OCFS2_HANDLE_SYNC; + else + handle->flags &= ~OCFS2_HANDLE_SYNC; +} + +/* Exported only for the journal struct init code in super.c. Do not call. */ +void ocfs2_complete_recovery(void *data); + +/* + * 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 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_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_alloc_handle - Only allocate a handle so we can start putting + * cluster locks on it. To actually change blocks, + * call ocfs2_start_trans with the handle returned + * from this function. You may call ocfs2_commit_trans + * at any time in the lifetime of a 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. + * 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. + * ocfs2_handle_add_lock - Sometimes we need to delay lock release + * until after a transaction has been completed. Use + * ocfs2_handle_add_lock to indicate that a lock needs + * to be released at the end of that handle. Locks + * will be released in the order that they are added. + * ocfs2_handle_add_inode - Add a locked inode to a transaction. + */ + +/* 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. */ +struct ocfs2_journal_handle *ocfs2_alloc_handle(struct ocfs2_super *osb); +struct ocfs2_journal_handle *ocfs2_start_trans(struct ocfs2_super *osb, + struct ocfs2_journal_handle *handle, + int max_buffs); +void ocfs2_commit_trans(struct ocfs2_journal_handle *handle); +int ocfs2_extend_trans(struct ocfs2_journal_handle *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(struct ocfs2_journal_handle *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(struct ocfs2_journal_handle *handle, + struct buffer_head *bh); +int ocfs2_journal_dirty_data(handle_t *handle, + struct buffer_head *bh); +int ocfs2_handle_add_lock(struct ocfs2_journal_handle *handle, + struct inode *inode); +/* + * Use this to protect from other processes reading buffer state while + * it's in flight. + */ +void ocfs2_handle_add_inode(struct ocfs2_journal_handle *handle, + struct inode *inode); + +/* + * 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) + +/* 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) + dir entry block */ +#define OCFS2_LINK_CREDITS (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 && + le32_to_cpu(last_el->l_recs[i].e_clusters) == clusters_to_del) + credits += 1 + tree_depth; + + /* update to the truncate log. */ + credits += OCFS2_TRUNCATE_LOG_UPDATE; + + return credits; +} + +#endif /* OCFS2_JOURNAL_H */ |