On Thu, Oct 19, 2017 at 2:41 PM, Jeff Moyer <jmoyer(a)redhat.com>
> jane.chu(a)oracle.com writes:
>> Hi, Dan,
>> Referring to
>> [RFC,2/2] mm, fs: daxfile, an interface for byte-addressable updates
>> to pmem
>> I'm unable to find the patch in Linux upstream kernel, and am wondering if
>> there has been a change of plan for providing support to byte granularity
>> read() and write() to character device /dev/dax.
>> I've also just started following the email threads, so I might have
>> missed some critical discussions. Would you mind to elaborate what's
>> happening to the proposed feature?
> Device dax only supports mmap for data path access. There are no plans
> to support read(2) or write(2).
Yes, and the patch set referenced about was not about read(2)/write(2)
it was about support for mmap writes without requiring them to be
backstopped by calls to msync(). That proposal morphed into the
MAP_SYNC and MAP_DIRECT proposals. MAP_SYNC is targeting 4.15.
MAP_DIRECT is being reworked into an RDMA-memory-registration-specific
Thank you both for the clarification!
Is there documents that elaborate the new resolve in detail?