/* -*- 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 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_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)
/* 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 */
