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From:   "Sungjong Seo" <sj1557.seo@samsung.com>
To:     "'Namjae Jeon'" <linkinjeon@kernel.org>,
        "'Kohada.Tetsuhiro@dc.MitsubishiElectric.co.jp'" 
        <Kohada.Tetsuhiro@dc.mitsubishielectric.co.jp>
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        <Mori.Takahiro@ab.mitsubishielectric.co.jp>,
        "'Motai.Hirotaka@aj.MitsubishiElectric.co.jp'" 
        <Motai.Hirotaka@aj.mitsubishielectric.co.jp>,
        "'Namjae Jeon'" <namjae.jeon@samsung.com>,
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        <kohada.t2@gmail.com>
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Subject: RE: [PATCH] exfat: optimize dir-cache
Date:   Wed, 27 May 2020 23:25:30 +0900
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> 2020-05-27 17:00 GMT+09:00,
> Kohada.Tetsuhiro@dc.MitsubishiElectric.co.jp
> <Kohada.Tetsuhiro@dc.mitsubishielectric.co.jp>:
> > Thank you for your comment.
> >
> >  >> +    for (i = 0; i < es->num_bh; i++) {
> >  >> +            if (es->modified)
> >  >> +                    exfat_update_bh(es->sb, es->bh[i], sync);
> >  >
> >  > Overall, it looks good to me.
> >  > However, if "sync" is set, it looks better to return the result of
> > exfat_update_bh().
> >  > Of course, a tiny modification for exfat_update_bh() is also required.
> >
> >  I thought the same, while creating this patch.
> >  However this patch has changed a lot and I didn't add any new error
> > checking.
> >  (So, the same behavior will occur even if an error occurs)
> >
> >  >> +struct exfat_dentry *exfat_get_dentry_cached(
> >  >> +    struct exfat_entry_set_cache *es, int num) {
> >  >> +    int off = es->start_off + num * DENTRY_SIZE;
> >  >> +    struct buffer_head *bh = es->bh[EXFAT_B_TO_BLK(off, es->sb)];
> >  >> +    char *p = bh->b_data + EXFAT_BLK_OFFSET(off, es->sb);
> >  >
> >  > In order to prevent illegal accesses to bh and dentries, it would
> > be better to check validation for num and bh.
> >
> >  There is no new error checking for same reason as above.
> >
> >  I'll try to add error checking to this v2 patch.
> >  Or is it better to add error checking in another patch?
> The latter:)
> Thanks!

Yes, the latter looks better.
Thanks!

> >
> > BR
> > ---
> > Kohada Tetsuhiro <Kohada.Tetsuhiro@dc.MitsubishiElectric.co.jp>