From: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>

If the DIO write on FAT is expanding the size, it will be fail by -EINVAL,
because FAT can't handle it now.

This patch fallback it to the normal buffered-write and would return
success.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 fs/fat/inode.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff -puN fs/fat/inode.c~fat-dio-write-fallback-to-normal-buffered fs/fat/inode.c
--- a/fs/fat/inode.c~fat-dio-write-fallback-to-normal-buffered
+++ a/fs/fat/inode.c
@@ -173,10 +173,12 @@ static ssize_t fat_direct_IO(int rw, str
 		 *
 		 * But we must fill the remaining area or hole by nul for
 		 * updating ->mmu_private.
+		 *
+		 * Return 0, and fallback to normal buffered write.
 		 */
 		loff_t size = offset + iov_length(iov, nr_segs);
 		if (MSDOS_I(inode)->mmu_private < size)
-			return -EINVAL;
+			return 0;
 	}
 
 	/*
_