On Thu, May 04, 2023 at 09:45:50AM +0100, John Garry wrote: > On 03/05/2023 22:58, Dave Chinner wrote: > > Is there a statx() man > > page update for this addition? > > No, not yet. Is it normally expected to provide a proposed man page update > in parallel? Or somewhat later, when the kernel API change has some > appreciable level of agreement? Normally we ask for man page updates to be presented at the same time, as the man page defines the user interface that is being implemented. In this case, we need updates for the pwritev2() man page to document RWF_ATOMIC semantics, and the statx() man page to document what the variables being exposed mean w.r.t. RWF_ATOMIC. The pwritev2() man page is probably the most important one right now - it needs to explain the guarantees that RWF_ATOMIC is supposed to provide w.r.t. data integrity, IO ordering, persistence, etc. Indeed, it will need to explain exactly how this "multi-atomic-unit mulit-bio non-atomic RWF_ATOMIC" IO thing can be used safely and reliably, especially w.r.t. IO ordering and persistence guarantees in the face of crashes and power failures. Not to mention documenting error conditions specific to RWF_ATOMIC... It's all well and good to have some implementation, but without actually defining and documenting the *guarantees* that RWF_ATOMIC provides userspace it is completely useless for application developers. And from the perspective of a reviewer, without the documentation stating what the infrastructure actually guarantees applications, we can't determine if the implementation being presented is fit for purpose.... Cheers, Dave. -- Dave Chinner david@xxxxxxxxxxxxx
