> On Fri, Feb 26, 2021 at 08:20:27AM +0800, Shiyang Ruan wrote: > > Some operations, such as comparing a range of data in two files under > > fsdax mode, requires nested iomap_open()/iomap_end() on two file. Thus, > > we introduce iomap_apply2() to accept arguments from two files and > > iomap_actor2_t for actions on two files. > > > > Signed-off-by: Shiyang Ruan <ruansy.fnst@xxxxxxxxxxx> > > --- > > fs/iomap/apply.c | 51 +++++++++++++++++++++++++++++++++++++++++++ > > include/linux/iomap.h | 7 +++++- > > 2 files changed, 57 insertions(+), 1 deletion(-) > > ... > > + ret = ops->iomap_begin(ino2, pos2, length, 0, &dmap, NULL); > > + if (ret) > > + goto out_dest; > > + if (WARN_ON(dmap.offset > pos2)) { > > + written = -EIO; > > + goto out_dest; > > + } > > + if (WARN_ON(dmap.length == 0)) { > > + written = -EIO; > > + goto out_dest; > > + } > > + > > + /* make sure extent length of two file is equal */ > > + if (WARN_ON(smap.length != dmap.length)) { > > Why not set smap.length and dmap.length to min(smap.length, dmap.length) ? > You are right. I found that I understood it wrong. My bad. I'll fix this patch and the next one which call this function. -- Thanks, Ruan Shiyang. > --D >