| Message ID | 53e290cb.rCYzzvUZ1cY/IQ85%akpm@linux-foundation.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Aug 06, 2014 at 01:32:11PM -0700, Andrew Morton wrote: > From: yangwenfang <vicky.yangwenfang@huawei.com> > Subject: 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. Putting the journal_access_di in ocfs2_write_end is the correct thing to do, thanks. I think we want to keep the journal_access_di in ocfs2_write_begin though as we may change the disk inode when marking unwritten extents (see the call to ocfs2_mark_extent_written()). So: - I would remove the comment above journal_access_di in write_begin but not the actual call as we may dirty the inode buffer later. - Move the call to journal_access_di to the top of ocfs2_write_end_nolock as I believe you might be missing some inode buffer updates there too. Thanks, --Mark -- Mark Fasheh
diff -puN fs/ocfs2/aops.c~ocfs2-call-ocfs2_journal_access_di-before-ocfs2_journal_dirty-in-ocfs2_write_end_nolock fs/ocfs2/aops.c --- a/fs/ocfs2/aops.c~ocfs2-call-ocfs2_journal_access_di-before-ocfs2_journal_dirty-in-ocfs2_write_end_nolock +++ a/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 addres 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 addres } } + 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);