Re: Direct IO for fat

[OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>]

Jan Kara <jack@suse.cz> writes:

>> I see. When I wrote this, I thought kernel should use DIO to write if
>> user sets O_DIRECT. Because the wrong alignment request isn't fallback
>> to buffered-write, and it's also returns EINVAL.
>   I understand. It's just that I've got some surprised users who could not
> track why the hell does write() return EINVAL to them when they have
> everything alligned and the same code works for EXT3 :). Of course, nothing
> guarantees that FAT should behave the same way as EXT3 but I can understand
> they were surprised (I had to look in the code too).
>   I also don't have a strong opinion whether we should fallback to buffered
> write automagically or whether we should return EINVAL and let the user fall
> back to the buffered write himself. But I'd slightly prefer the first
> option.

Hm, ok. I'll change EINVAL to zero as soon as possible after test.

Thanks.
-- 
OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>