Re: [PATCH v12 4/4] ext4: Use generic casefolding support

[Daniel Rosenberg]

On Mon, Sep 21, 2020 at 11:29 AM Eric Biggers <ebiggers@xxxxxxxxxx> wrote:
>
> On Sun, Sep 20, 2020 at 09:10:57PM -0400, Gabriel Krisman Bertazi wrote:
> > Daniel Rosenberg <drosen@xxxxxxxxxx> writes:
> >
> > > This switches ext4 over to the generic support provided in
> > > the previous patch.
> > >
> > > Since casefolded dentries behave the same in ext4 and f2fs, we decrease
> > > the maintenance burden by unifying them, and any optimizations will
> > > immediately apply to both.
> > >
> > > Signed-off-by: Daniel Rosenberg <drosen@xxxxxxxxxx>
> > > Reviewed-by: Eric Biggers <ebiggers@xxxxxxxxxx>
> > >
> > >  #ifdef CONFIG_UNICODE
> > > -   if (EXT4_SB(parent->i_sb)->s_encoding && IS_CASEFOLDED(parent)) {
> > > +   if (parent->i_sb->s_encoding && IS_CASEFOLDED(parent)) {
> > >             if (fname->cf_name.name) {
> > >                     struct qstr cf = {.name = fname->cf_name.name,
> > >                                       .len = fname->cf_name.len};
> > > @@ -2171,9 +2171,6 @@ static int ext4_add_entry(handle_t *handle, struct dentry *dentry,
> > >     struct buffer_head *bh = NULL;
> > >     struct ext4_dir_entry_2 *de;
> > >     struct super_block *sb;
> > > -#ifdef CONFIG_UNICODE
> > > -   struct ext4_sb_info *sbi;
> > > -#endif
> > >     struct ext4_filename fname;
> > >     int     retval;
> > >     int     dx_fallback=0;
> > > @@ -2190,9 +2187,8 @@ static int ext4_add_entry(handle_t *handle, struct dentry *dentry,
> > >             return -EINVAL;
> > >
> > >  #ifdef CONFIG_UNICODE
> > > -   sbi = EXT4_SB(sb);
> > > -   if (ext4_has_strict_mode(sbi) && IS_CASEFOLDED(dir) &&
> > > -       sbi->s_encoding && utf8_validate(sbi->s_encoding, &dentry->d_name))
> > > +   if (sb_has_strict_encoding(sb) && IS_CASEFOLDED(dir) &&
> > > +       sb->s_encoding && utf8_validate(sb->s_encoding, &dentry->d_name))
> > >             return -EINVAL;
> >
> > hm, just noticed the sb->s_encoding check here is superfluous, since the
> > has_strict_mode() cannot be true if !s_encoding.  Not related to this
> > patch though.
> >
> > Daniel, are you still working on getting this upstream?  The fscrypt
> > support would be very useful for us. :)
> >
> > In the hope this will get upstream, as its been flying for a while and
> > looks correct.
> >
> > Reviewed-by: Gabriel Krisman Bertazi <krisman@xxxxxxxxxxxxx>
>
> We couldn't get a response from Ted, so instead Jaegeuk has applied patches 1-3
> to f2fs/dev for 5.10.  Hopefully Ted will take the ext4 patch for 5.11.
>
> I believe that Daniel is planning to resend the actual encryption+casefolding
> support soon, but initially only for f2fs since that will be ready first.
>
> - Eric

Yes, planning to send them shortly. Just checking that I've not missed
anything. For the sb_has_strict_encoding, I don't think that's
actually checking s_encoding, though it does check s_encoding_flags.
I'm planning to resend this one with that set, since it's not queued
in the f2fs tree.

-Daniel