With Christoph Hellwig <hch@lst.de>

These patches adds the `-o sync' and `-o dirsync' supports to fatfs.  If user
specified that option, the fatfs does traditional ordered updates by using
synchronous writes.  If compared to before, these patches will show a
improvement of robustness I think.

`-o sync'    - writes all buffers out before returning from syscall.
`-o dirsync' - writes the directory's metadata, and unreferencing
               operations of data block.

    remaining to be done
         fat_generic_ioctl(), fat_notify_change(),
	 ATTR_ARCH of fat_xxx_write[v],
	 and probably, filling hole in cont_prepare_write(),

NOTE: Since fatfs doesn't have link-count, unfortunately ->rename() is
not safe order at all.  It may make the shared blocks, but user
shouldn't lose the data by ->rename().

If you test this, please use the dosfstools at

	http://www.zip.com.au/~akpm/linux/patches/stuff/fatfsprogs.tar.bz2

This is fixing several bugs of dosfstools.  And "2/29" patch from hpa adds new
ioctl, the attached archive is also including the commands for testing it.


This patch fixes vectored write support on fat to do the nessecary
non-standard action done in write() aswell.

Also adds aio support and makes read/write wrappers around the aio
version.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>