diff options
| -rw-r--r-- | fs/jbd/commit.c | 182 |
1 files changed, 113 insertions, 69 deletions
diff --git a/fs/jbd/commit.c b/fs/jbd/commit.c index 42da607..32a8caf 100644 --- a/fs/jbd/commit.c +++ b/fs/jbd/commit.c @@ -160,6 +160,117 @@ static int journal_write_commit_record(journal_t *journal, return (ret == -EIO); } +static void journal_do_submit_data(struct buffer_head **wbuf, int bufs) +{ + int i; + + for (i = 0; i < bufs; i++) { + wbuf[i]->b_end_io = end_buffer_write_sync; + /* We use-up our safety reference in submit_bh() */ + submit_bh(WRITE, wbuf[i]); + } +} + +/* + * Submit all the data buffers to disk + */ +static void journal_submit_data_buffers(journal_t *journal, + transaction_t *commit_transaction) +{ + struct journal_head *jh; + struct buffer_head *bh; + int locked; + int bufs = 0; + struct buffer_head **wbuf = journal->j_wbuf; + + /* + * Whenever we unlock the journal and sleep, things can get added + * onto ->t_sync_datalist, so we have to keep looping back to + * write_out_data until we *know* that the list is empty. + * + * Cleanup any flushed data buffers from the data list. Even in + * abort mode, we want to flush this out as soon as possible. + */ +write_out_data: + cond_resched(); + spin_lock(&journal->j_list_lock); + + while (commit_transaction->t_sync_datalist) { + jh = commit_transaction->t_sync_datalist; + bh = jh2bh(jh); + locked = 0; + + /* Get reference just to make sure buffer does not disappear + * when we are forced to drop various locks */ + get_bh(bh); + /* If the buffer is dirty, we need to submit IO and hence + * we need the buffer lock. We try to lock the buffer without + * blocking. If we fail, we need to drop j_list_lock and do + * blocking lock_buffer(). + */ + if (buffer_dirty(bh)) { + if (test_set_buffer_locked(bh)) { + BUFFER_TRACE(bh, "needs blocking lock"); + spin_unlock(&journal->j_list_lock); + /* Write out all data to prevent deadlocks */ + journal_do_submit_data(wbuf, bufs); + bufs = 0; + lock_buffer(bh); + spin_lock(&journal->j_list_lock); + } + locked = 1; + } + /* We have to get bh_state lock. Again out of order, sigh. */ + if (!inverted_lock(journal, bh)) { + jbd_lock_bh_state(bh); + spin_lock(&journal->j_list_lock); + } + /* Someone already cleaned up the buffer? */ + if (!buffer_jbd(bh) + || jh->b_transaction != commit_transaction + || jh->b_jlist != BJ_SyncData) { + jbd_unlock_bh_state(bh); + if (locked) + unlock_buffer(bh); + BUFFER_TRACE(bh, "already cleaned up"); + put_bh(bh); + continue; + } + if (locked && test_clear_buffer_dirty(bh)) { + BUFFER_TRACE(bh, "needs writeout, adding to array"); + wbuf[bufs++] = bh; + __journal_file_buffer(jh, commit_transaction, + BJ_Locked); + jbd_unlock_bh_state(bh); + if (bufs == journal->j_wbufsize) { + spin_unlock(&journal->j_list_lock); + journal_do_submit_data(wbuf, bufs); + bufs = 0; + goto write_out_data; + } + } + else { + BUFFER_TRACE(bh, "writeout complete: unfile"); + __journal_unfile_buffer(jh); + jbd_unlock_bh_state(bh); + if (locked) + unlock_buffer(bh); + journal_remove_journal_head(bh); + /* Once for our safety reference, once for + * journal_remove_journal_head() */ + put_bh(bh); + put_bh(bh); + } + + if (lock_need_resched(&journal->j_list_lock)) { + spin_unlock(&journal->j_list_lock); + goto write_out_data; + } + } + spin_unlock(&journal->j_list_lock); + journal_do_submit_data(wbuf, bufs); +} + /* * journal_commit_transaction * @@ -313,80 +424,13 @@ void journal_commit_transaction(journal_t *journal) * Now start flushing things to disk, in the order they appear * on the transaction lists. Data blocks go first. */ - err = 0; - /* - * Whenever we unlock the journal and sleep, things can get added - * onto ->t_sync_datalist, so we have to keep looping back to - * write_out_data until we *know* that the list is empty. - */ - bufs = 0; - /* - * Cleanup any flushed data buffers from the data list. Even in - * abort mode, we want to flush this out as soon as possible. - */ -write_out_data: - cond_resched(); - spin_lock(&journal->j_list_lock); - - while (commit_transaction->t_sync_datalist) { - struct buffer_head *bh; - - jh = commit_transaction->t_sync_datalist; - commit_transaction->t_sync_datalist = jh->b_tnext; - bh = jh2bh(jh); - if (buffer_locked(bh)) { - BUFFER_TRACE(bh, "locked"); - if (!inverted_lock(journal, bh)) - goto write_out_data; - __journal_temp_unlink_buffer(jh); - __journal_file_buffer(jh, commit_transaction, - BJ_Locked); - jbd_unlock_bh_state(bh); - if (lock_need_resched(&journal->j_list_lock)) { - spin_unlock(&journal->j_list_lock); - goto write_out_data; - } - } else { - if (buffer_dirty(bh)) { - BUFFER_TRACE(bh, "start journal writeout"); - get_bh(bh); - wbuf[bufs++] = bh; - if (bufs == journal->j_wbufsize) { - jbd_debug(2, "submit %d writes\n", - bufs); - spin_unlock(&journal->j_list_lock); - ll_rw_block(SWRITE, bufs, wbuf); - journal_brelse_array(wbuf, bufs); - bufs = 0; - goto write_out_data; - } - } else { - BUFFER_TRACE(bh, "writeout complete: unfile"); - if (!inverted_lock(journal, bh)) - goto write_out_data; - __journal_unfile_buffer(jh); - jbd_unlock_bh_state(bh); - journal_remove_journal_head(bh); - put_bh(bh); - if (lock_need_resched(&journal->j_list_lock)) { - spin_unlock(&journal->j_list_lock); - goto write_out_data; - } - } - } - } - - if (bufs) { - spin_unlock(&journal->j_list_lock); - ll_rw_block(SWRITE, bufs, wbuf); - journal_brelse_array(wbuf, bufs); - spin_lock(&journal->j_list_lock); - } + journal_submit_data_buffers(journal, commit_transaction); /* * Wait for all previously submitted IO to complete. */ + spin_lock(&journal->j_list_lock); while (commit_transaction->t_locked_list) { struct buffer_head *bh; |
