From: Andrey Borzenkov <arvidjaar@mail.ru>
To: hirofumi@mail.parknet.co.jp
Subject: Long file names in VFAT broken with iocharset=utf8
Date: Mon, 7 May 2007 21:51:14 +0400
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This was posted in one of Russian forums. It was not possible to archive=20
(under Linux, using tar) vfat directory where files had long Russian names=
=20
(really long - over 150 - 170 characters) - tar returned stat failure. When=
=20
looking with plain ls, file names appeared truncated.

Now looking at current (2.6.21) fat driver, __fat_readdir allocates large=20
enough buffer (PAGE_SIZE-522) for UTF-8 name; but for iocharset=3Dutf8 it c=
alls=20
uni16_to_x8() which artificially limits length of UTF-8 name to 256 ... whi=
ch=20
is obviously not enough for long UTF-8 Russian string (2 bytes per characte=
r)=20
not to mention the - theoretical - general case of 6 bytes UTF-8 characters.

Similar problem has apparently vfat_lookup()->...->fat_search_long() call=20
chain. Except this appears to be broken even in case of "utf8", because=20
fat_search_long allocates fixed 256 bytes buffer for UTF-8 name.

Am I off track here?

=2Dandrey

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