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![Zhihao Cheng](/assets/img/avatar_default.png)
[ Upstream commite34c8dd238
] Following process, jbd2_journal_commit_transaction // there are several dirty buffer heads in transaction->t_checkpoint_list P1 wb_workfn jbd2_log_do_checkpoint if (buffer_locked(bh)) // false __block_write_full_page trylock_buffer(bh) test_clear_buffer_dirty(bh) if (!buffer_dirty(bh)) __jbd2_journal_remove_checkpoint(jh) if (buffer_write_io_error(bh)) // false >> bh IO error occurs << jbd2_cleanup_journal_tail __jbd2_update_log_tail jbd2_write_superblock // The bh won't be replayed in next mount. , which could corrupt the ext4 image, fetch a reproducer in [Link]. Since writeback process clears buffer dirty after locking buffer head, we can fix it by try locking buffer and check dirtiness while buffer is locked, the buffer head can be removed if it is neither dirty nor locked. Link: https://bugzilla.kernel.org/show_bug.cgi?id=217490 Fixes:470decc613
("[PATCH] jbd2: initial copy of files from jbd") Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com> Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20230606135928.434610-5-yi.zhang@huaweicloud.com Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Sasha Levin <sashal@kernel.org>
766 lines
22 KiB
C
766 lines
22 KiB
C
// SPDX-License-Identifier: GPL-2.0+
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/*
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* linux/fs/jbd2/checkpoint.c
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*
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* Written by Stephen C. Tweedie <sct@redhat.com>, 1999
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*
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* Copyright 1999 Red Hat Software --- All Rights Reserved
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*
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* Checkpoint routines for the generic filesystem journaling code.
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* Part of the ext2fs journaling system.
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*
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* Checkpointing is the process of ensuring that a section of the log is
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* committed fully to disk, so that that portion of the log can be
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* reused.
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*/
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#include <linux/time.h>
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#include <linux/fs.h>
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#include <linux/jbd2.h>
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#include <linux/errno.h>
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#include <linux/slab.h>
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#include <linux/blkdev.h>
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#include <trace/events/jbd2.h>
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/*
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* Unlink a buffer from a transaction checkpoint list.
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*
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* Called with j_list_lock held.
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*/
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static inline void __buffer_unlink_first(struct journal_head *jh)
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{
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transaction_t *transaction = jh->b_cp_transaction;
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jh->b_cpnext->b_cpprev = jh->b_cpprev;
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jh->b_cpprev->b_cpnext = jh->b_cpnext;
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if (transaction->t_checkpoint_list == jh) {
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transaction->t_checkpoint_list = jh->b_cpnext;
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if (transaction->t_checkpoint_list == jh)
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transaction->t_checkpoint_list = NULL;
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}
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}
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/*
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* Unlink a buffer from a transaction checkpoint(io) list.
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*
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* Called with j_list_lock held.
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*/
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static inline void __buffer_unlink(struct journal_head *jh)
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{
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transaction_t *transaction = jh->b_cp_transaction;
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__buffer_unlink_first(jh);
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if (transaction->t_checkpoint_io_list == jh) {
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transaction->t_checkpoint_io_list = jh->b_cpnext;
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if (transaction->t_checkpoint_io_list == jh)
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transaction->t_checkpoint_io_list = NULL;
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}
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}
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/*
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* Check a checkpoint buffer could be release or not.
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*
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* Requires j_list_lock
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*/
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static inline bool __cp_buffer_busy(struct journal_head *jh)
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{
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struct buffer_head *bh = jh2bh(jh);
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return (jh->b_transaction || buffer_locked(bh) || buffer_dirty(bh));
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}
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/*
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* __jbd2_log_wait_for_space: wait until there is space in the journal.
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*
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* Called under j-state_lock *only*. It will be unlocked if we have to wait
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* for a checkpoint to free up some space in the log.
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*/
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void __jbd2_log_wait_for_space(journal_t *journal)
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__acquires(&journal->j_state_lock)
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__releases(&journal->j_state_lock)
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{
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int nblocks, space_left;
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/* assert_spin_locked(&journal->j_state_lock); */
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nblocks = journal->j_max_transaction_buffers;
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while (jbd2_log_space_left(journal) < nblocks) {
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write_unlock(&journal->j_state_lock);
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mutex_lock_io(&journal->j_checkpoint_mutex);
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/*
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* Test again, another process may have checkpointed while we
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* were waiting for the checkpoint lock. If there are no
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* transactions ready to be checkpointed, try to recover
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* journal space by calling cleanup_journal_tail(), and if
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* that doesn't work, by waiting for the currently committing
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* transaction to complete. If there is absolutely no way
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* to make progress, this is either a BUG or corrupted
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* filesystem, so abort the journal and leave a stack
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* trace for forensic evidence.
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*/
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write_lock(&journal->j_state_lock);
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if (journal->j_flags & JBD2_ABORT) {
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mutex_unlock(&journal->j_checkpoint_mutex);
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return;
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}
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spin_lock(&journal->j_list_lock);
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space_left = jbd2_log_space_left(journal);
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if (space_left < nblocks) {
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int chkpt = journal->j_checkpoint_transactions != NULL;
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tid_t tid = 0;
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if (journal->j_committing_transaction)
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tid = journal->j_committing_transaction->t_tid;
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spin_unlock(&journal->j_list_lock);
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write_unlock(&journal->j_state_lock);
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if (chkpt) {
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jbd2_log_do_checkpoint(journal);
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} else if (jbd2_cleanup_journal_tail(journal) == 0) {
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/* We were able to recover space; yay! */
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;
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} else if (tid) {
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/*
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* jbd2_journal_commit_transaction() may want
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* to take the checkpoint_mutex if JBD2_FLUSHED
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* is set. So we need to temporarily drop it.
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*/
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mutex_unlock(&journal->j_checkpoint_mutex);
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jbd2_log_wait_commit(journal, tid);
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write_lock(&journal->j_state_lock);
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continue;
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} else {
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printk(KERN_ERR "%s: needed %d blocks and "
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"only had %d space available\n",
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__func__, nblocks, space_left);
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printk(KERN_ERR "%s: no way to get more "
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"journal space in %s\n", __func__,
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journal->j_devname);
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WARN_ON(1);
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jbd2_journal_abort(journal, -EIO);
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}
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write_lock(&journal->j_state_lock);
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} else {
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spin_unlock(&journal->j_list_lock);
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}
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mutex_unlock(&journal->j_checkpoint_mutex);
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}
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}
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static void
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__flush_batch(journal_t *journal, int *batch_count)
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{
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int i;
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struct blk_plug plug;
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blk_start_plug(&plug);
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for (i = 0; i < *batch_count; i++)
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write_dirty_buffer(journal->j_chkpt_bhs[i], REQ_SYNC);
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blk_finish_plug(&plug);
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for (i = 0; i < *batch_count; i++) {
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struct buffer_head *bh = journal->j_chkpt_bhs[i];
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BUFFER_TRACE(bh, "brelse");
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__brelse(bh);
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journal->j_chkpt_bhs[i] = NULL;
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}
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*batch_count = 0;
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}
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/*
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* Perform an actual checkpoint. We take the first transaction on the
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* list of transactions to be checkpointed and send all its buffers
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* to disk. We submit larger chunks of data at once.
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*
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* The journal should be locked before calling this function.
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* Called with j_checkpoint_mutex held.
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*/
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int jbd2_log_do_checkpoint(journal_t *journal)
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{
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struct journal_head *jh;
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struct buffer_head *bh;
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transaction_t *transaction;
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tid_t this_tid;
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int result, batch_count = 0;
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jbd2_debug(1, "Start checkpoint\n");
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/*
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* First thing: if there are any transactions in the log which
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* don't need checkpointing, just eliminate them from the
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* journal straight away.
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*/
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result = jbd2_cleanup_journal_tail(journal);
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trace_jbd2_checkpoint(journal, result);
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jbd2_debug(1, "cleanup_journal_tail returned %d\n", result);
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if (result <= 0)
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return result;
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/*
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* OK, we need to start writing disk blocks. Take one transaction
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* and write it.
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*/
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spin_lock(&journal->j_list_lock);
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if (!journal->j_checkpoint_transactions)
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goto out;
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transaction = journal->j_checkpoint_transactions;
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if (transaction->t_chp_stats.cs_chp_time == 0)
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transaction->t_chp_stats.cs_chp_time = jiffies;
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this_tid = transaction->t_tid;
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restart:
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/*
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* If someone cleaned up this transaction while we slept, we're
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* done (maybe it's a new transaction, but it fell at the same
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* address).
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*/
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if (journal->j_checkpoint_transactions != transaction ||
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transaction->t_tid != this_tid)
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goto out;
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/* checkpoint all of the transaction's buffers */
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while (transaction->t_checkpoint_list) {
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jh = transaction->t_checkpoint_list;
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bh = jh2bh(jh);
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if (jh->b_transaction != NULL) {
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transaction_t *t = jh->b_transaction;
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tid_t tid = t->t_tid;
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transaction->t_chp_stats.cs_forced_to_close++;
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spin_unlock(&journal->j_list_lock);
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if (unlikely(journal->j_flags & JBD2_UNMOUNT))
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/*
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* The journal thread is dead; so
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* starting and waiting for a commit
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* to finish will cause us to wait for
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* a _very_ long time.
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*/
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printk(KERN_ERR
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"JBD2: %s: Waiting for Godot: block %llu\n",
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journal->j_devname, (unsigned long long) bh->b_blocknr);
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if (batch_count)
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__flush_batch(journal, &batch_count);
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jbd2_log_start_commit(journal, tid);
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/*
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* jbd2_journal_commit_transaction() may want
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* to take the checkpoint_mutex if JBD2_FLUSHED
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* is set, jbd2_update_log_tail() called by
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* jbd2_journal_commit_transaction() may also take
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* checkpoint_mutex. So we need to temporarily
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* drop it.
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*/
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mutex_unlock(&journal->j_checkpoint_mutex);
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jbd2_log_wait_commit(journal, tid);
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mutex_lock_io(&journal->j_checkpoint_mutex);
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spin_lock(&journal->j_list_lock);
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goto restart;
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}
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if (!trylock_buffer(bh)) {
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/*
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* The buffer is locked, it may be writing back, or
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* flushing out in the last couple of cycles, or
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* re-adding into a new transaction, need to check
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* it again until it's unlocked.
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*/
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get_bh(bh);
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spin_unlock(&journal->j_list_lock);
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wait_on_buffer(bh);
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/* the journal_head may have gone by now */
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BUFFER_TRACE(bh, "brelse");
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__brelse(bh);
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goto retry;
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} else if (!buffer_dirty(bh)) {
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unlock_buffer(bh);
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BUFFER_TRACE(bh, "remove from checkpoint");
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/*
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* If the transaction was released or the checkpoint
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* list was empty, we're done.
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*/
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if (__jbd2_journal_remove_checkpoint(jh) ||
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!transaction->t_checkpoint_list)
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goto out;
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} else {
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unlock_buffer(bh);
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/*
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* We are about to write the buffer, it could be
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* raced by some other transaction shrink or buffer
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* re-log logic once we release the j_list_lock,
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* leave it on the checkpoint list and check status
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* again to make sure it's clean.
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*/
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BUFFER_TRACE(bh, "queue");
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get_bh(bh);
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J_ASSERT_BH(bh, !buffer_jwrite(bh));
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journal->j_chkpt_bhs[batch_count++] = bh;
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transaction->t_chp_stats.cs_written++;
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transaction->t_checkpoint_list = jh->b_cpnext;
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}
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if ((batch_count == JBD2_NR_BATCH) ||
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need_resched() || spin_needbreak(&journal->j_list_lock) ||
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jh2bh(transaction->t_checkpoint_list) == journal->j_chkpt_bhs[0])
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goto unlock_and_flush;
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}
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if (batch_count) {
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unlock_and_flush:
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spin_unlock(&journal->j_list_lock);
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retry:
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if (batch_count)
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__flush_batch(journal, &batch_count);
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spin_lock(&journal->j_list_lock);
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goto restart;
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}
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out:
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spin_unlock(&journal->j_list_lock);
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result = jbd2_cleanup_journal_tail(journal);
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return (result < 0) ? result : 0;
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}
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/*
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* Check the list of checkpoint transactions for the journal to see if
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* we have already got rid of any since the last update of the log tail
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* in the journal superblock. If so, we can instantly roll the
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* superblock forward to remove those transactions from the log.
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*
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* Return <0 on error, 0 on success, 1 if there was nothing to clean up.
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*
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* Called with the journal lock held.
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*
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* This is the only part of the journaling code which really needs to be
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* aware of transaction aborts. Checkpointing involves writing to the
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* main filesystem area rather than to the journal, so it can proceed
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* even in abort state, but we must not update the super block if
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* checkpointing may have failed. Otherwise, we would lose some metadata
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* buffers which should be written-back to the filesystem.
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*/
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int jbd2_cleanup_journal_tail(journal_t *journal)
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{
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tid_t first_tid;
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unsigned long blocknr;
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if (is_journal_aborted(journal))
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return -EIO;
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if (!jbd2_journal_get_log_tail(journal, &first_tid, &blocknr))
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return 1;
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J_ASSERT(blocknr != 0);
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/*
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* We need to make sure that any blocks that were recently written out
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* --- perhaps by jbd2_log_do_checkpoint() --- are flushed out before
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* we drop the transactions from the journal. It's unlikely this will
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* be necessary, especially with an appropriately sized journal, but we
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* need this to guarantee correctness. Fortunately
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* jbd2_cleanup_journal_tail() doesn't get called all that often.
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*/
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if (journal->j_flags & JBD2_BARRIER)
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blkdev_issue_flush(journal->j_fs_dev);
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return __jbd2_update_log_tail(journal, first_tid, blocknr);
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}
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|
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/* Checkpoint list management */
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/*
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* journal_clean_one_cp_list
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*
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* Find all the written-back checkpoint buffers in the given list and
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* release them. If 'destroy' is set, clean all buffers unconditionally.
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*
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* Called with j_list_lock held.
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* Returns 1 if we freed the transaction, 0 otherwise.
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*/
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static int journal_clean_one_cp_list(struct journal_head *jh, bool destroy)
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{
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struct journal_head *last_jh;
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struct journal_head *next_jh = jh;
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if (!jh)
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return 0;
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last_jh = jh->b_cpprev;
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do {
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jh = next_jh;
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next_jh = jh->b_cpnext;
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|
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if (!destroy && __cp_buffer_busy(jh))
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return 0;
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|
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if (__jbd2_journal_remove_checkpoint(jh))
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return 1;
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/*
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* This function only frees up some memory
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* if possible so we dont have an obligation
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* to finish processing. Bail out if preemption
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* requested:
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*/
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if (need_resched())
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return 0;
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} while (jh != last_jh);
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|
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return 0;
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}
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|
|
/*
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* journal_shrink_one_cp_list
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*
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* Find 'nr_to_scan' written-back checkpoint buffers in the given list
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* and try to release them. If the whole transaction is released, set
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* the 'released' parameter. Return the number of released checkpointed
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* buffers.
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*
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* Called with j_list_lock held.
|
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*/
|
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static unsigned long journal_shrink_one_cp_list(struct journal_head *jh,
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unsigned long *nr_to_scan,
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bool *released)
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{
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struct journal_head *last_jh;
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struct journal_head *next_jh = jh;
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unsigned long nr_freed = 0;
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int ret;
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|
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if (!jh || *nr_to_scan == 0)
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return 0;
|
|
|
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last_jh = jh->b_cpprev;
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do {
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jh = next_jh;
|
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next_jh = jh->b_cpnext;
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|
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(*nr_to_scan)--;
|
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if (__cp_buffer_busy(jh))
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continue;
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|
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nr_freed++;
|
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ret = __jbd2_journal_remove_checkpoint(jh);
|
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if (ret) {
|
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*released = true;
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break;
|
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}
|
|
|
|
if (need_resched())
|
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break;
|
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} while (jh != last_jh && *nr_to_scan);
|
|
|
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return nr_freed;
|
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}
|
|
|
|
/*
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* jbd2_journal_shrink_checkpoint_list
|
|
*
|
|
* Find 'nr_to_scan' written-back checkpoint buffers in the journal
|
|
* and try to release them. Return the number of released checkpointed
|
|
* buffers.
|
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*
|
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* Called with j_list_lock held.
|
|
*/
|
|
unsigned long jbd2_journal_shrink_checkpoint_list(journal_t *journal,
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|
unsigned long *nr_to_scan)
|
|
{
|
|
transaction_t *transaction, *last_transaction, *next_transaction;
|
|
bool released;
|
|
tid_t first_tid = 0, last_tid = 0, next_tid = 0;
|
|
tid_t tid = 0;
|
|
unsigned long nr_freed = 0;
|
|
unsigned long nr_scanned = *nr_to_scan;
|
|
|
|
again:
|
|
spin_lock(&journal->j_list_lock);
|
|
if (!journal->j_checkpoint_transactions) {
|
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spin_unlock(&journal->j_list_lock);
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* Get next shrink transaction, resume previous scan or start
|
|
* over again. If some others do checkpoint and drop transaction
|
|
* from the checkpoint list, we ignore saved j_shrink_transaction
|
|
* and start over unconditionally.
|
|
*/
|
|
if (journal->j_shrink_transaction)
|
|
transaction = journal->j_shrink_transaction;
|
|
else
|
|
transaction = journal->j_checkpoint_transactions;
|
|
|
|
if (!first_tid)
|
|
first_tid = transaction->t_tid;
|
|
last_transaction = journal->j_checkpoint_transactions->t_cpprev;
|
|
next_transaction = transaction;
|
|
last_tid = last_transaction->t_tid;
|
|
do {
|
|
transaction = next_transaction;
|
|
next_transaction = transaction->t_cpnext;
|
|
tid = transaction->t_tid;
|
|
released = false;
|
|
|
|
nr_freed += journal_shrink_one_cp_list(transaction->t_checkpoint_list,
|
|
nr_to_scan, &released);
|
|
if (*nr_to_scan == 0)
|
|
break;
|
|
if (need_resched() || spin_needbreak(&journal->j_list_lock))
|
|
break;
|
|
if (released)
|
|
continue;
|
|
|
|
nr_freed += journal_shrink_one_cp_list(transaction->t_checkpoint_io_list,
|
|
nr_to_scan, &released);
|
|
if (*nr_to_scan == 0)
|
|
break;
|
|
if (need_resched() || spin_needbreak(&journal->j_list_lock))
|
|
break;
|
|
} while (transaction != last_transaction);
|
|
|
|
if (transaction != last_transaction) {
|
|
journal->j_shrink_transaction = next_transaction;
|
|
next_tid = next_transaction->t_tid;
|
|
} else {
|
|
journal->j_shrink_transaction = NULL;
|
|
next_tid = 0;
|
|
}
|
|
|
|
spin_unlock(&journal->j_list_lock);
|
|
cond_resched();
|
|
|
|
if (*nr_to_scan && next_tid)
|
|
goto again;
|
|
out:
|
|
nr_scanned -= *nr_to_scan;
|
|
trace_jbd2_shrink_checkpoint_list(journal, first_tid, tid, last_tid,
|
|
nr_freed, nr_scanned, next_tid);
|
|
|
|
return nr_freed;
|
|
}
|
|
|
|
/*
|
|
* journal_clean_checkpoint_list
|
|
*
|
|
* Find all the written-back checkpoint buffers in the journal and release them.
|
|
* If 'destroy' is set, release all buffers unconditionally.
|
|
*
|
|
* Called with j_list_lock held.
|
|
*/
|
|
void __jbd2_journal_clean_checkpoint_list(journal_t *journal, bool destroy)
|
|
{
|
|
transaction_t *transaction, *last_transaction, *next_transaction;
|
|
int ret;
|
|
|
|
transaction = journal->j_checkpoint_transactions;
|
|
if (!transaction)
|
|
return;
|
|
|
|
last_transaction = transaction->t_cpprev;
|
|
next_transaction = transaction;
|
|
do {
|
|
transaction = next_transaction;
|
|
next_transaction = transaction->t_cpnext;
|
|
ret = journal_clean_one_cp_list(transaction->t_checkpoint_list,
|
|
destroy);
|
|
/*
|
|
* This function only frees up some memory if possible so we
|
|
* dont have an obligation to finish processing. Bail out if
|
|
* preemption requested:
|
|
*/
|
|
if (need_resched())
|
|
return;
|
|
if (ret)
|
|
continue;
|
|
/*
|
|
* It is essential that we are as careful as in the case of
|
|
* t_checkpoint_list with removing the buffer from the list as
|
|
* we can possibly see not yet submitted buffers on io_list
|
|
*/
|
|
ret = journal_clean_one_cp_list(transaction->
|
|
t_checkpoint_io_list, destroy);
|
|
if (need_resched())
|
|
return;
|
|
/*
|
|
* Stop scanning if we couldn't free the transaction. This
|
|
* avoids pointless scanning of transactions which still
|
|
* weren't checkpointed.
|
|
*/
|
|
if (!ret)
|
|
return;
|
|
} while (transaction != last_transaction);
|
|
}
|
|
|
|
/*
|
|
* Remove buffers from all checkpoint lists as journal is aborted and we just
|
|
* need to free memory
|
|
*/
|
|
void jbd2_journal_destroy_checkpoint(journal_t *journal)
|
|
{
|
|
/*
|
|
* We loop because __jbd2_journal_clean_checkpoint_list() may abort
|
|
* early due to a need of rescheduling.
|
|
*/
|
|
while (1) {
|
|
spin_lock(&journal->j_list_lock);
|
|
if (!journal->j_checkpoint_transactions) {
|
|
spin_unlock(&journal->j_list_lock);
|
|
break;
|
|
}
|
|
__jbd2_journal_clean_checkpoint_list(journal, true);
|
|
spin_unlock(&journal->j_list_lock);
|
|
cond_resched();
|
|
}
|
|
}
|
|
|
|
/*
|
|
* journal_remove_checkpoint: called after a buffer has been committed
|
|
* to disk (either by being write-back flushed to disk, or being
|
|
* committed to the log).
|
|
*
|
|
* We cannot safely clean a transaction out of the log until all of the
|
|
* buffer updates committed in that transaction have safely been stored
|
|
* elsewhere on disk. To achieve this, all of the buffers in a
|
|
* transaction need to be maintained on the transaction's checkpoint
|
|
* lists until they have been rewritten, at which point this function is
|
|
* called to remove the buffer from the existing transaction's
|
|
* checkpoint lists.
|
|
*
|
|
* The function returns 1 if it frees the transaction, 0 otherwise.
|
|
* The function can free jh and bh.
|
|
*
|
|
* This function is called with j_list_lock held.
|
|
*/
|
|
int __jbd2_journal_remove_checkpoint(struct journal_head *jh)
|
|
{
|
|
struct transaction_chp_stats_s *stats;
|
|
transaction_t *transaction;
|
|
journal_t *journal;
|
|
struct buffer_head *bh = jh2bh(jh);
|
|
|
|
JBUFFER_TRACE(jh, "entry");
|
|
|
|
transaction = jh->b_cp_transaction;
|
|
if (!transaction) {
|
|
JBUFFER_TRACE(jh, "not on transaction");
|
|
return 0;
|
|
}
|
|
journal = transaction->t_journal;
|
|
|
|
JBUFFER_TRACE(jh, "removing from transaction");
|
|
|
|
/*
|
|
* If we have failed to write the buffer out to disk, the filesystem
|
|
* may become inconsistent. We cannot abort the journal here since
|
|
* we hold j_list_lock and we have to be careful about races with
|
|
* jbd2_journal_destroy(). So mark the writeback IO error in the
|
|
* journal here and we abort the journal later from a better context.
|
|
*/
|
|
if (buffer_write_io_error(bh))
|
|
set_bit(JBD2_CHECKPOINT_IO_ERROR, &journal->j_atomic_flags);
|
|
|
|
__buffer_unlink(jh);
|
|
jh->b_cp_transaction = NULL;
|
|
percpu_counter_dec(&journal->j_checkpoint_jh_count);
|
|
jbd2_journal_put_journal_head(jh);
|
|
|
|
/* Is this transaction empty? */
|
|
if (transaction->t_checkpoint_list || transaction->t_checkpoint_io_list)
|
|
return 0;
|
|
|
|
/*
|
|
* There is one special case to worry about: if we have just pulled the
|
|
* buffer off a running or committing transaction's checkpoing list,
|
|
* then even if the checkpoint list is empty, the transaction obviously
|
|
* cannot be dropped!
|
|
*
|
|
* The locking here around t_state is a bit sleazy.
|
|
* See the comment at the end of jbd2_journal_commit_transaction().
|
|
*/
|
|
if (transaction->t_state != T_FINISHED)
|
|
return 0;
|
|
|
|
/*
|
|
* OK, that was the last buffer for the transaction, we can now
|
|
* safely remove this transaction from the log.
|
|
*/
|
|
stats = &transaction->t_chp_stats;
|
|
if (stats->cs_chp_time)
|
|
stats->cs_chp_time = jbd2_time_diff(stats->cs_chp_time,
|
|
jiffies);
|
|
trace_jbd2_checkpoint_stats(journal->j_fs_dev->bd_dev,
|
|
transaction->t_tid, stats);
|
|
|
|
__jbd2_journal_drop_transaction(journal, transaction);
|
|
jbd2_journal_free_transaction(transaction);
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
* journal_insert_checkpoint: put a committed buffer onto a checkpoint
|
|
* list so that we know when it is safe to clean the transaction out of
|
|
* the log.
|
|
*
|
|
* Called with the journal locked.
|
|
* Called with j_list_lock held.
|
|
*/
|
|
void __jbd2_journal_insert_checkpoint(struct journal_head *jh,
|
|
transaction_t *transaction)
|
|
{
|
|
JBUFFER_TRACE(jh, "entry");
|
|
J_ASSERT_JH(jh, buffer_dirty(jh2bh(jh)) || buffer_jbddirty(jh2bh(jh)));
|
|
J_ASSERT_JH(jh, jh->b_cp_transaction == NULL);
|
|
|
|
/* Get reference for checkpointing transaction */
|
|
jbd2_journal_grab_journal_head(jh2bh(jh));
|
|
jh->b_cp_transaction = transaction;
|
|
|
|
if (!transaction->t_checkpoint_list) {
|
|
jh->b_cpnext = jh->b_cpprev = jh;
|
|
} else {
|
|
jh->b_cpnext = transaction->t_checkpoint_list;
|
|
jh->b_cpprev = transaction->t_checkpoint_list->b_cpprev;
|
|
jh->b_cpprev->b_cpnext = jh;
|
|
jh->b_cpnext->b_cpprev = jh;
|
|
}
|
|
transaction->t_checkpoint_list = jh;
|
|
percpu_counter_inc(&transaction->t_journal->j_checkpoint_jh_count);
|
|
}
|
|
|
|
/*
|
|
* We've finished with this transaction structure: adios...
|
|
*
|
|
* The transaction must have no links except for the checkpoint by this
|
|
* point.
|
|
*
|
|
* Called with the journal locked.
|
|
* Called with j_list_lock held.
|
|
*/
|
|
|
|
void __jbd2_journal_drop_transaction(journal_t *journal, transaction_t *transaction)
|
|
{
|
|
assert_spin_locked(&journal->j_list_lock);
|
|
|
|
journal->j_shrink_transaction = NULL;
|
|
if (transaction->t_cpnext) {
|
|
transaction->t_cpnext->t_cpprev = transaction->t_cpprev;
|
|
transaction->t_cpprev->t_cpnext = transaction->t_cpnext;
|
|
if (journal->j_checkpoint_transactions == transaction)
|
|
journal->j_checkpoint_transactions =
|
|
transaction->t_cpnext;
|
|
if (journal->j_checkpoint_transactions == transaction)
|
|
journal->j_checkpoint_transactions = NULL;
|
|
}
|
|
|
|
J_ASSERT(transaction->t_state == T_FINISHED);
|
|
J_ASSERT(transaction->t_buffers == NULL);
|
|
J_ASSERT(transaction->t_forget == NULL);
|
|
J_ASSERT(transaction->t_shadow_list == NULL);
|
|
J_ASSERT(transaction->t_checkpoint_list == NULL);
|
|
J_ASSERT(transaction->t_checkpoint_io_list == NULL);
|
|
J_ASSERT(atomic_read(&transaction->t_updates) == 0);
|
|
J_ASSERT(journal->j_committing_transaction != transaction);
|
|
J_ASSERT(journal->j_running_transaction != transaction);
|
|
|
|
trace_jbd2_drop_transaction(journal, transaction);
|
|
|
|
jbd2_debug(1, "Dropping transaction %d, all done\n", transaction->t_tid);
|
|
}
|