From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Return-Path: Message-ID: <1498768325.5710.6.camel@poochiereds.net> Subject: Re: [PATCH v8 18/18] btrfs: minimal conversion to errseq_t writeback error reporting on fsync From: Jeff Layton To: Christoph Hellwig , jlayton@kernel.org Cc: Andrew Morton , Al Viro , Jan Kara , tytso@mit.edu, axboe@kernel.dk, mawilcox@microsoft.com, ross.zwisler@linux.intel.com, corbet@lwn.net, Chris Mason , Josef Bacik , David Sterba , "Darrick J . Wong" , Carlos Maiolino , Eryu Guan , David Howells , Liu Bo , linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-ext4@vger.kernel.org, linux-xfs@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-block@vger.kernel.org Date: Thu, 29 Jun 2017 16:32:05 -0400 In-Reply-To: <20170629141741.GC17251@infradead.org> References: <20170629131954.28733-1-jlayton@kernel.org> <20170629131954.28733-19-jlayton@kernel.org> <20170629141741.GC17251@infradead.org> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 List-ID: On Thu, 2017-06-29 at 07:17 -0700, Christoph Hellwig wrote: > On Thu, Jun 29, 2017 at 09:19:54AM -0400, jlayton@kernel.org wrote: > > From: Jeff Layton > > > > Just check and advance the errseq_t in the file before returning. > > Internal callers of filemap_* functions are left as-is. > > > > Signed-off-by: Jeff Layton > > --- > > fs/btrfs/file.c | 7 +++++-- > > 1 file changed, 5 insertions(+), 2 deletions(-) > > > > diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c > > index da1096eb1a40..1f57e1a523d9 100644 > > --- a/fs/btrfs/file.c > > +++ b/fs/btrfs/file.c > > @@ -2011,7 +2011,7 @@ int btrfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync) > > struct btrfs_root *root = BTRFS_I(inode)->root; > > struct btrfs_trans_handle *trans; > > struct btrfs_log_ctx ctx; > > - int ret = 0; > > + int ret = 0, err; > > bool full_sync = 0; > > u64 len; > > > > @@ -2030,7 +2030,7 @@ int btrfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync) > > */ > > ret = start_ordered_ops(inode, start, end); > > if (ret) > > - return ret; > > + goto out; > > > > inode_lock(inode); > > atomic_inc(&root->log_batch); > > @@ -2227,6 +2227,9 @@ int btrfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync) > > ret = btrfs_end_transaction(trans); > > } > > out: > > + err = file_check_and_advance_wb_err(file); > > + if (!ret) > > + ret = err; > > return ret > 0 ? -EIO : ret; > > This means that we'll lose the exact error returned from > start_ordered_ops. Beyond that I can't really provide good feedback > as the btrfs fsync code looks so much different from all the other > fs fsync code.. Well, no...we'll keep the error from start_ordered_ops if there was one. We just advance the cursor past any stored error in that case without returning it. I have another fix for this patch too: there's a call to filemap_check_errors in this function that I think should probably use filemap_check_wb_err instead. Fixed in my tree. I do agree though that while this works in my testing I'd like the btrfs guys to ACK this as I don't fully grok the btrfs fsync code at all. -- Jeff Layton