On Tue 01-08-17 04:02:41, Christoph Hellwig wrote: > On Fri, Jul 28, 2017 at 11:38:21AM +0200, Jan Kara wrote: > > Well, you are right I can make the implementation work with struct file > > flag as well - let's call it O_DAXDSYNC. However there are filesystem > > operations where you may need to answer question: Is there any fd with > > O_DAXDSYNC open against this inode (for operations that change file offset > > -> block mapping)? And in that case inode flag is straightforward while > > file flag is a bit awkward (you need to implement counter of fd's with that > > flag in the inode). > > We can still keep and inode flag as the internal implementation > detail. As mentioned earlier the right flag to control behavior > of a mapping is an mmap flag. And the initial naive implementation > would simply mark the inode as sync once the first MAP_SYNC open happens > on it. We could then move to more precise tracking if/when needed. OK, makes sense and I like the MAP_SYNC proposal. I'll change it in my implementation. Honza -- Jan Kara <jack@xxxxxxxx> SUSE Labs, CR
