if (jh->b_transaction == NULL && !buffer_locked(bh) &&
!buffer_dirty(bh) && !buffer_write_io_error(bh)) {
- /*
- * Get our reference so that bh cannot be freed before
- * we unlock it
- */
- get_bh(bh);
JBUFFER_TRACE(jh, "remove from checkpoint list");
ret = __jbd2_journal_remove_checkpoint(jh) + 1;
- BUFFER_TRACE(bh, "release");
- __brelse(bh);
}
return ret;
}
nblocks = jbd2_space_needed(journal);
while (jbd2_log_space_left(journal) < nblocks) {
- if (journal->j_flags & JBD2_ABORT)
- return;
write_unlock(&journal->j_state_lock);
mutex_lock(&journal->j_checkpoint_mutex);
* trace for forensic evidence.
*/
write_lock(&journal->j_state_lock);
+ if (journal->j_flags & JBD2_ABORT) {
+ mutex_unlock(&journal->j_checkpoint_mutex);
+ return;
+ }
spin_lock(&journal->j_list_lock);
nblocks = jbd2_space_needed(journal);
space_left = jbd2_log_space_left(journal);
}
}
-/*
- * Clean up transaction's list of buffers submitted for io.
- * We wait for any pending IO to complete and remove any clean
- * buffers. Note that we take the buffers in the opposite ordering
- * from the one in which they were submitted for IO.
- *
- * Return 0 on success, and return <0 if some buffers have failed
- * to be written out.
- *
- * Called with j_list_lock held.
- */
-static int __wait_cp_io(journal_t *journal, transaction_t *transaction)
-{
- struct journal_head *jh;
- struct buffer_head *bh;
- tid_t this_tid;
- int released = 0;
- int ret = 0;
-
- this_tid = transaction->t_tid;
-restart:
- /* Did somebody clean up the transaction in the meanwhile? */
- if (journal->j_checkpoint_transactions != transaction ||
- transaction->t_tid != this_tid)
- return ret;
- while (!released && transaction->t_checkpoint_io_list) {
- jh = transaction->t_checkpoint_io_list;
- bh = jh2bh(jh);
- get_bh(bh);
- if (buffer_locked(bh)) {
- spin_unlock(&journal->j_list_lock);
- wait_on_buffer(bh);
- /* the journal_head may have gone by now */
- BUFFER_TRACE(bh, "brelse");
- __brelse(bh);
- spin_lock(&journal->j_list_lock);
- goto restart;
- }
- if (unlikely(buffer_write_io_error(bh)))
- ret = -EIO;
-
- /*
- * Now in whatever state the buffer currently is, we know that
- * it has been written out and so we can drop it from the list
- */
- released = __jbd2_journal_remove_checkpoint(jh);
- __brelse(bh);
- }
-
- return ret;
-}
-
static void
__flush_batch(journal_t *journal, int *batch_count)
{
*batch_count = 0;
}
-/*
- * Try to flush one buffer from the checkpoint list to disk.
- *
- * Return 1 if something happened which requires us to abort the current
- * scan of the checkpoint list. Return <0 if the buffer has failed to
- * be written out.
- *
- * Called with j_list_lock held and drops it if 1 is returned
- */
-static int __process_buffer(journal_t *journal, struct journal_head *jh,
- int *batch_count, transaction_t *transaction)
-{
- struct buffer_head *bh = jh2bh(jh);
- int ret = 0;
-
- if (buffer_locked(bh)) {
- get_bh(bh);
- spin_unlock(&journal->j_list_lock);
- wait_on_buffer(bh);
- /* the journal_head may have gone by now */
- BUFFER_TRACE(bh, "brelse");
- __brelse(bh);
- ret = 1;
- } else if (jh->b_transaction != NULL) {
- transaction_t *t = jh->b_transaction;
- tid_t tid = t->t_tid;
-
- transaction->t_chp_stats.cs_forced_to_close++;
- spin_unlock(&journal->j_list_lock);
- if (unlikely(journal->j_flags & JBD2_UNMOUNT))
- /*
- * The journal thread is dead; so starting and
- * waiting for a commit to finish will cause
- * us to wait for a _very_ long time.
- */
- printk(KERN_ERR "JBD2: %s: "
- "Waiting for Godot: block %llu\n",
- journal->j_devname,
- (unsigned long long) bh->b_blocknr);
- jbd2_log_start_commit(journal, tid);
- jbd2_log_wait_commit(journal, tid);
- ret = 1;
- } else if (!buffer_dirty(bh)) {
- ret = 1;
- if (unlikely(buffer_write_io_error(bh)))
- ret = -EIO;
- get_bh(bh);
- BUFFER_TRACE(bh, "remove from checkpoint");
- __jbd2_journal_remove_checkpoint(jh);
- spin_unlock(&journal->j_list_lock);
- __brelse(bh);
- } else {
- /*
- * Important: we are about to write the buffer, and
- * possibly block, while still holding the journal lock.
- * We cannot afford to let the transaction logic start
- * messing around with this buffer before we write it to
- * disk, as that would break recoverability.
- */
- BUFFER_TRACE(bh, "queue");
- get_bh(bh);
- J_ASSERT_BH(bh, !buffer_jwrite(bh));
- journal->j_chkpt_bhs[*batch_count] = bh;
- __buffer_relink_io(jh);
- transaction->t_chp_stats.cs_written++;
- (*batch_count)++;
- if (*batch_count == JBD2_NR_BATCH) {
- spin_unlock(&journal->j_list_lock);
- __flush_batch(journal, batch_count);
- ret = 1;
- }
- }
- return ret;
-}
-
/*
* Perform an actual checkpoint. We take the first transaction on the
* list of transactions to be checkpointed and send all its buffers
*/
int jbd2_log_do_checkpoint(journal_t *journal)
{
- transaction_t *transaction;
- tid_t this_tid;
- int result;
+ struct journal_head *jh;
+ struct buffer_head *bh;
+ transaction_t *transaction;
+ tid_t this_tid;
+ int result, batch_count = 0;
jbd_debug(1, "Start checkpoint\n");
* done (maybe it's a new transaction, but it fell at the same
* address).
*/
- if (journal->j_checkpoint_transactions == transaction &&
- transaction->t_tid == this_tid) {
- int batch_count = 0;
- struct journal_head *jh;
- int retry = 0, err;
-
- while (!retry && transaction->t_checkpoint_list) {
- jh = transaction->t_checkpoint_list;
- retry = __process_buffer(journal, jh, &batch_count,
- transaction);
- if (retry < 0 && !result)
- result = retry;
- if (!retry && (need_resched() ||
- spin_needbreak(&journal->j_list_lock))) {
- spin_unlock(&journal->j_list_lock);
- retry = 1;
- break;
- }
+ if (journal->j_checkpoint_transactions != transaction ||
+ transaction->t_tid != this_tid)
+ goto out;
+
+ /* checkpoint all of the transaction's buffers */
+ while (transaction->t_checkpoint_list) {
+ jh = transaction->t_checkpoint_list;
+ bh = jh2bh(jh);
+
+ if (buffer_locked(bh)) {
+ spin_unlock(&journal->j_list_lock);
+ get_bh(bh);
+ wait_on_buffer(bh);
+ /* the journal_head may have gone by now */
+ BUFFER_TRACE(bh, "brelse");
+ __brelse(bh);
+ goto retry;
}
+ if (jh->b_transaction != NULL) {
+ transaction_t *t = jh->b_transaction;
+ tid_t tid = t->t_tid;
- if (batch_count) {
- if (!retry) {
- spin_unlock(&journal->j_list_lock);
- retry = 1;
- }
- __flush_batch(journal, &batch_count);
+ transaction->t_chp_stats.cs_forced_to_close++;
+ spin_unlock(&journal->j_list_lock);
+ if (unlikely(journal->j_flags & JBD2_UNMOUNT))
+ /*
+ * The journal thread is dead; so
+ * starting and waiting for a commit
+ * to finish will cause us to wait for
+ * a _very_ long time.
+ */
+ printk(KERN_ERR
+ "JBD2: %s: Waiting for Godot: block %llu\n",
+ journal->j_devname, (unsigned long long) bh->b_blocknr);
+
+ jbd2_log_start_commit(journal, tid);
+ jbd2_log_wait_commit(journal, tid);
+ goto retry;
+ }
+ if (!buffer_dirty(bh)) {
+ if (unlikely(buffer_write_io_error(bh)) && !result)
+ result = -EIO;
+ BUFFER_TRACE(bh, "remove from checkpoint");
+ if (__jbd2_journal_remove_checkpoint(jh))
+ /* The transaction was released; we're done */
+ goto out;
+ continue;
}
+ /*
+ * Important: we are about to write the buffer, and
+ * possibly block, while still holding the journal
+ * lock. We cannot afford to let the transaction
+ * logic start messing around with this buffer before
+ * we write it to disk, as that would break
+ * recoverability.
+ */
+ BUFFER_TRACE(bh, "queue");
+ get_bh(bh);
+ J_ASSERT_BH(bh, !buffer_jwrite(bh));
+ journal->j_chkpt_bhs[batch_count++] = bh;
+ __buffer_relink_io(jh);
+ transaction->t_chp_stats.cs_written++;
+ if ((batch_count == JBD2_NR_BATCH) ||
+ need_resched() ||
+ spin_needbreak(&journal->j_list_lock))
+ goto unlock_and_flush;
+ }
- if (retry) {
+ if (batch_count) {
+ unlock_and_flush:
+ spin_unlock(&journal->j_list_lock);
+ retry:
+ if (batch_count)
+ __flush_batch(journal, &batch_count);
spin_lock(&journal->j_list_lock);
goto restart;
+ }
+
+ /*
+ * Now we issued all of the transaction's buffers, let's deal
+ * with the buffers that are out for I/O.
+ */
+restart2:
+ /* Did somebody clean up the transaction in the meanwhile? */
+ if (journal->j_checkpoint_transactions != transaction ||
+ transaction->t_tid != this_tid)
+ goto out;
+
+ while (transaction->t_checkpoint_io_list) {
+ jh = transaction->t_checkpoint_io_list;
+ bh = jh2bh(jh);
+ if (buffer_locked(bh)) {
+ spin_unlock(&journal->j_list_lock);
+ get_bh(bh);
+ wait_on_buffer(bh);
+ /* the journal_head may have gone by now */
+ BUFFER_TRACE(bh, "brelse");
+ __brelse(bh);
+ spin_lock(&journal->j_list_lock);
+ goto restart2;
}
+ if (unlikely(buffer_write_io_error(bh)) && !result)
+ result = -EIO;
+
/*
- * Now we have cleaned up the first transaction's checkpoint
- * list. Let's clean up the second one
+ * Now in whatever state the buffer currently is, we
+ * know that it has been written out and so we can
+ * drop it from the list
*/
- err = __wait_cp_io(journal, transaction);
- if (!result)
- result = err;
+ if (__jbd2_journal_remove_checkpoint(jh))
+ break;
}
out:
spin_unlock(&journal->j_list_lock);
projects / mirror_ubuntu-bionic-kernel.git / blobdiff