Yang, (Sorry if I've used your last name lately) Am 20.08.2015 um 05:00 schrieb Dongsheng Yang: > On 08/20/2015 04:35 AM, Richard Weinberger wrote: >> Currently UBIFS does not support direct IO, but some applications >> blindly use the O_DIRECT flag. >> Instead of failing upon open() we can do better and fall back >> to buffered IO. > > Hmmmm, to be honest, I am not sure we have to do it as Dave > suggested. I think that's just a work-around for current fstests. > > IMHO, perform a buffered IO when user request direct IO without > any warning sounds not a good idea. Maybe adding a warning would > make it better. Well, how would you inform the user? A printk() to dmesg is useless are the vast majority of open() callers do not check dmesg... :) Major filesystems implement ->direct_IO these days and having a "return 0"-stub seems to be legit. For example exofs does too. So, I really don't consider it a work around. > I think we need more discussion about AIO&DIO in ubifs, and actually > I have a plan for it. But I have not listed the all cons and pros of > it so far. Sure, having a real ->direct_IO would be be best solution. My patch won't block this. Thanks, //richard -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
