On Thu, Jul 18, 2019 at 04:43:52PM -0700, Bjorn Andersson wrote: > On Thu 18 Jul 16:17 PDT 2019, Al Viro wrote: > > > On Thu, Jul 18, 2019 at 04:10:54PM -0700, Bjorn Andersson wrote: > > > Implement a wrapper for aio_read()/write() to allow async IO on files > > > not implementing the iter version of read/write, such as sysfs. This > > > mimics how readv/writev uses non-iter ops in do_loop_readv_writev(). > > > > IDGI. How would that IO manage to be async? And what's the point > > using aio in such situations in the first place? > > The point is that an application using aio to submit io operations on a > set of files, ... for no reason whatsoever, I take it? > can use the same mechanism to read/write files that > happens to be implemented by driver only implementing read/write (not > read_iter/write_iter) in the registered file_operations struct, such as > kernfs. ... except that it still has to support the kernels that don't have your patch, so the fallback in userland is *not* going away.
