On Mon 24-04-17 13:14:36, Jeff Layton wrote: > On Mon, 2017-04-24 at 18:04 +0200, Jan Kara wrote: > > On Mon 24-04-17 09:22:49, Jeff Layton wrote: > > > This ensures that we see errors on fsync when writeback fails. > > > > > > Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx> > > > > Hum, but do we really want to clobber mapping errors with temporary stuff > > like ENOMEM? Or do you want to handle that in mapping_set_error? > > > > Right now we don't really have such a thing as temporary errors in the > writeback codepath. If you return an error here, the data doesn't stay > dirty or anything, and I think we want to ensure that that gets reported > via fsync. > > I'd like to see us add better handling for retryable errors for stuff > like ENOMEM or EAGAIN. I think this is the first step toward that > though. Once we have more consistent handling of writeback errors in > general, then we can start doing more interesting things with retryable > errors. > > So yeah, I this is the right thing to do for now. OK, fair enough. And question number 2): Who is actually responsible for setting the error in the mapping when error happens inside ->writepage()? Is it the ->writepage() callback or the caller of ->writepage()? Or something else? Currently it seems to be a strange mix (e.g. mm/page-writeback.c: __writepage() calls mapping_set_error() when ->writepage() returns error) so I'd like to understand what's the plan and have that recorded in the changelogs. Honza > > > > > > --- > > > fs/fuse/file.c | 1 + > > > 1 file changed, 1 insertion(+) > > > > > > diff --git a/fs/fuse/file.c b/fs/fuse/file.c > > > index ec238fb5a584..07d0efcb050c 100644 > > > --- a/fs/fuse/file.c > > > +++ b/fs/fuse/file.c > > > @@ -1669,6 +1669,7 @@ static int fuse_writepage_locked(struct page *page) > > > err_free: > > > fuse_request_free(req); > > > err: > > > + mapping_set_error(page->mapping, error); > > > end_page_writeback(page); > > > return error; > > > } > > > -- > > > 2.9.3 > > > > > > > > -- > Jeff Layton <jlayton@xxxxxxxxxx> -- Jan Kara <jack@xxxxxxxx> SUSE Labs, CR
