On Mon, 2022-05-30 at 14:13 +0200, Miklos Szeredi wrote: > On Mon, 23 May 2022 at 03:35, ChenXiaoSong <chenxiaosong2@xxxxxxxxxx> > wrote: > > > > As filemap_check_errors() only report -EIO or -ENOSPC, we return > > more nuanced > > writeback error -(file->f_mapping->wb_err & MAX_ERRNO). > > > > filemap_write_and_wait > > filemap_write_and_wait_range > > filemap_check_errors > > -ENOSPC or -EIO > > filemap_check_wb_err > > errseq_check > > return -(file->f_mapping->wb_err & MAX_ERRNO) > > > > Signed-off-by: ChenXiaoSong <chenxiaosong2@xxxxxxxxxx> > > --- > > fs/fuse/file.c | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/fs/fuse/file.c b/fs/fuse/file.c > > index f18d14d5fea1..9917bc2795e6 100644 > > --- a/fs/fuse/file.c > > +++ b/fs/fuse/file.c > > @@ -488,10 +488,10 @@ static int fuse_flush(struct file *file, > > fl_owner_t id) > > inode_unlock(inode); > > > > err = filemap_check_errors(file->f_mapping); > > + /* return more nuanced writeback errors */ > > if (err) > > - return err; > > + return filemap_check_wb_err(file->f_mapping, 0); > > I'm wondering if this should be file_check_and_advance_wb_err() > instead. > > Is there a difference between ->flush() and ->fsync()? > > Jeff, can you please help? > Hi Miklos, We just went through this discussion for the case of NFS. The point is that ->flush() is only called on close(). While you can report errors in close(), the 'man 2 fsync' manpage documents that post-Linux 4.13, the writeback errors are required to be returned on - >fsync(). You should therefore not be calling file_check_and_advance_wb_err() in anything that is being called as part of close() since that will clear the error from the errseq_t and prevent it from being reported in a future fsync() call from a dup()ed file descriptor, etc. NFS also wants to make a special case out of write() when we know that the error is one of EDQUOT, EFBIG or ENOSPC, in which case we will also use file_check_and_advance_wb_err() to return the error immediately, and clear it from the errseq_t. -- Trond Myklebust Linux NFS client maintainer, Hammerspace trond.myklebust@xxxxxxxxxxxxxxx
