Re: [PATCH v8 02/13] exfat: add super block operations

From: Namjae Jeon
Date: Thu Jan 02 2020 - 08:13:54 EST


2020-01-02 17:30 GMT+09:00, Pali RohÃr <pali.rohar@xxxxxxxxx>:
> On Thursday 02 January 2020 15:06:16 Namjae Jeon wrote:
>> > > +static const struct fs_parameter_spec exfat_param_specs[] = {
>> > > + fsparam_u32("uid", Opt_uid),
>> > > + fsparam_u32("gid", Opt_gid),
>> > > + fsparam_u32oct("umask", Opt_umask),
>> > > + fsparam_u32oct("dmask", Opt_dmask),
>> > > + fsparam_u32oct("fmask", Opt_fmask),
>> > > + fsparam_u32oct("allow_utime", Opt_allow_utime),
>> > > + fsparam_string("iocharset", Opt_charset),
>> > > + fsparam_flag("utf8", Opt_utf8),
>> >
>> > Hello! What is the purpose of having extra special "utf8" mount option?
>> > Is not one "iocharset=utf8" option enough?
>> utf8 nls_table supports utf8<->utf32 conversion and does not support
>> surrogate character conversion.
>
> So in other words, this is just subset of UTF-8 just to 3 byte long
> sequences (for Unicode code points up to the U+FFFF).
>
>> The utf8 option can support the surrogate
>> character conversion of utf16 using utf16s_to_utf8s/utf8s_to_utf16s of
>> the nls base.
>
> So this is full UTF-8 support, right?
>
> And what is the point to have two options for UTF-8 support, when one is
> incomplete / broken? I see no benefit to have first option at all.
> Providing incomplete / broken support to userspace does not make much
> sense if we already have full and working support via different mount
> option. Maybe second option with full UTF-8 support should be used also
> by iocharset=utf8 and then we do not need utf8 option at all?
Make sense. I will make it one option.

Thanks!
>
> --
> Pali RohÃr
> pali.rohar@xxxxxxxxx
>