From 9a08ea92a859e6e8ee21e46635ae20670e8edfdb Mon Sep 17 00:00:00 2001 From: yangwenfang Date: Thu, 26 Jun 2014 10:42:23 +1000 Subject: [PATCH] ocfs2: call ocfs2_journal_access_di() before ocfs2_journal_dirty() in ocfs2_write_end_nolock() After we call ocfs2_journal_access_di() in ocfs2_write_begin(), jbd2_journal_restart() may also be called, in this function transaction A's t_updates-- and obtains a new transaction B. If jbd2_journal_commit_transaction() is happened to commit transaction A, when t_updates==0, it will continue to complete commit and unfile buffer. So when jbd2_journal_dirty_metadata(), the handle is pointed a new transaction B, and the buffer head's journal head is already freed, jh->b_transaction == NULL, jh->b_next_transaction == NULL, it returns EINVAL, So it triggers the BUG_ON(status). thread 1: jbd2: ocfs2_write_begin jbd2_journal_commit_transaction ocfs2_write_begin_nolock ocfs2_start_trans jbd2__journal_start(t_updates+1, transaction A) ocfs2_journal_access_di ocfs2_write_cluster_by_desc ocfs2_mark_extent_written ocfs2_change_extent_flag ocfs2_split_extent ocfs2_extend_rotate_transaction jbd2_journal_restart (t_updates-1,transaction B) t_updates==0 __jbd2_journal_refile_buffer ocfs2_write_end ocfs2_write_end_nolock ocfs2_journal_dirty jbd2_journal_dirty_metadata(bug) ocfs2_commit_trans In ext4, I found that: jbd2_journal_get_write_access() called by ext4_write_end. ext4_write_begin ext4_journal_start __ext4_journal_start_sb ext4_journal_check_start jbd2__journal_start ext4_write_end ext4_mark_inode_dirty ext4_reserve_inode_write ext4_journal_get_write_access jbd2_journal_get_write_access ext4_mark_iloc_dirty ext4_do_update_inode ext4_handle_dirty_metadata jbd2_journal_dirty_metadata So I think we should put ocfs2_journal_access_di before ocfs2_journal_dirty in the ocfs2_write_end. and it works well after my modification. Signed-off-by: vicky Cc: Mark Fasheh Cc: Joel Becker Signed-off-by: Andrew Morton --- fs/ocfs2/aops.c | 21 ++++++++++----------- 1 file changed, 10 insertions(+), 11 deletions(-) diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c index 4a231a166cf8..a06b23773384 100644 --- a/fs/ocfs2/aops.c +++ b/fs/ocfs2/aops.c @@ -1817,16 +1817,6 @@ try_again: if (ret) goto out_commit; } - /* - * We don't want this to fail in ocfs2_write_end(), so do it - * here. - */ - ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), wc->w_di_bh, - OCFS2_JOURNAL_ACCESS_WRITE); - if (ret) { - mlog_errno(ret); - goto out_quota; - } /* * Fill our page array first. That way we've grabbed enough so @@ -1977,7 +1967,7 @@ int ocfs2_write_end_nolock(struct address_space *mapping, loff_t pos, unsigned len, unsigned copied, struct page *page, void *fsdata) { - int i; + int i, ret; unsigned from, to, start = pos & (PAGE_CACHE_SIZE - 1); struct inode *inode = mapping->host; struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); @@ -2027,6 +2017,14 @@ int ocfs2_write_end_nolock(struct address_space *mapping, } } + ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), wc->w_di_bh, + OCFS2_JOURNAL_ACCESS_WRITE); + if (ret) { + copied = ret; + mlog_errno(ret); + goto out; + } + out_write_size: pos += copied; if (pos > i_size_read(inode)) { @@ -2041,6 +2039,7 @@ out_write_size: ocfs2_update_inode_fsync_trans(handle, inode, 1); ocfs2_journal_dirty(handle, wc->w_di_bh); +out: ocfs2_commit_trans(osb, handle); ocfs2_run_deallocs(osb, &wc->w_dealloc); -- 2.39.5