Re: CVS commit: src/sys/fs/tmpfs

[Joerg Sonnenberger <joerg%bec.de@localhost>]

On Wed, Jan 11, 2017 at 09:12:33PM +0000, David Holland wrote:
> On Wed, Jan 11, 2017 at 12:12:33PM +0000, Joerg Sonnenberger wrote:
>  > Modified Files:
>  > 	src/sys/fs/tmpfs: tmpfs_vnops.c
>  > 
>  > Log Message:
>  > Remove RO check in tmpfs_putpages for now, the syncer doesn't like the
>  > error code.
> 
> Either removing it is wrong or it should be changed to KASSERT :-)

So the problem is that the syncer will unconditionally call putpages
e.g. on umount. It might need a two stage approach for dealing with
dirty mmapped pages to implement properly, but for the use cases of
read-only tmpfs I have (and likely others), it doesn't really matter.
E.g. if you want to build multiple build chroots without paying for the
extreme locking penalty of nullfs.

Joerg