On Sun 13-08-17 02:25:56, Christoph Hellwig wrote: > On Sat, Aug 12, 2017 at 07:44:14PM -0700, Dan Williams wrote: > > How about MAP_SYNC == (MAP_SHARED|MAP_PRIVATE)? On older kernels that > > should get -EINVAL, and on new kernels it means SYNC+SHARED. > > Cute trick, but I'd hate to waster it just for our little flag. > > How about: > > #define __MAP_VALIDATE MAP_SHARED|MAP_PRIVATE > #define MAP_SYNC 0x??? | __MAP_VALIDATE > > so that we can reuse that trick for any new flag? Heh, that's such an ugly hack that it is cute ;)... I'll use this definition of MAP_SYNC in my patches and send new version of the series (probably today in the afternoon if the testing goes fine). Honza -- Jan Kara <jack@xxxxxxxx> SUSE Labs, CR
