On 06/10/2017 12:34 AM, Al Viro wrote:

On Thu, Jun 08, 2017 at 12:39:10AM -0700, Christoph Hellwig wrote:

quoted

As already indicated this whole series looks fine to me.

Al: are you going to pick this up?  Or Andrew?

The main issue here is "let's bail out from ->write_iter() instances"
patch.  It very obviously has holes in coverage.

Could we have FMODE_AIO_NOWAIT and make those who claim to support it
set that in ->open()?  And make aio check that and bail out if asked
for nowait on a file without that flag...

Yes, I would agree.

We had FS_NOWAIT in filesystem type flags (in v3), but retracted it
later in v4.

Another option could be to keep the feature against FS_REQUIRES_DEV to
rule out filesystems which are not local, but it again has the problem
of holes in coverage.

I will work on adding FMODE_AIO_NOWAIT in the meantime.

Thanks,

-- 
Goldwyn